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1/*
2 * Simplified MAC Kernel (smack) security module
3 *
4 * This file contains the smack hook function implementations.
5 *
6 * Authors:
7 * Casey Schaufler <casey@schaufler-ca.com>
8 * Jarkko Sakkinen <jarkko.sakkinen@intel.com>
9 *
10 * Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com>
11 * Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
12 * Paul Moore <paul@paul-moore.com>
13 * Copyright (C) 2010 Nokia Corporation
14 * Copyright (C) 2011 Intel Corporation.
15 *
16 * This program is free software; you can redistribute it and/or modify
17 * it under the terms of the GNU General Public License version 2,
18 * as published by the Free Software Foundation.
19 */
20
21#include <linux/xattr.h>
22#include <linux/pagemap.h>
23#include <linux/mount.h>
24#include <linux/stat.h>
25#include <linux/kd.h>
26#include <asm/ioctls.h>
27#include <linux/ip.h>
28#include <linux/tcp.h>
29#include <linux/udp.h>
30#include <linux/dccp.h>
31#include <linux/slab.h>
32#include <linux/mutex.h>
33#include <linux/pipe_fs_i.h>
34#include <net/cipso_ipv4.h>
35#include <net/ip.h>
36#include <net/ipv6.h>
37#include <linux/audit.h>
38#include <linux/magic.h>
39#include <linux/dcache.h>
40#include <linux/personality.h>
41#include <linux/msg.h>
42#include <linux/shm.h>
43#include <linux/binfmts.h>
44#include <linux/parser.h>
45#include "smack.h"
46
47#define TRANS_TRUE "TRUE"
48#define TRANS_TRUE_SIZE 4
49
50#define SMK_CONNECTING 0
51#define SMK_RECEIVING 1
52#define SMK_SENDING 2
53
54#ifdef SMACK_IPV6_PORT_LABELING
55DEFINE_MUTEX(smack_ipv6_lock);
56static LIST_HEAD(smk_ipv6_port_list);
57#endif
58static struct kmem_cache *smack_inode_cache;
59int smack_enabled;
60
61static const match_table_t smk_mount_tokens = {
62 {Opt_fsdefault, SMK_FSDEFAULT "%s"},
63 {Opt_fsfloor, SMK_FSFLOOR "%s"},
64 {Opt_fshat, SMK_FSHAT "%s"},
65 {Opt_fsroot, SMK_FSROOT "%s"},
66 {Opt_fstransmute, SMK_FSTRANS "%s"},
67 {Opt_error, NULL},
68};
69
70#ifdef CONFIG_SECURITY_SMACK_BRINGUP
71static char *smk_bu_mess[] = {
72 "Bringup Error", /* Unused */
73 "Bringup", /* SMACK_BRINGUP_ALLOW */
74 "Unconfined Subject", /* SMACK_UNCONFINED_SUBJECT */
75 "Unconfined Object", /* SMACK_UNCONFINED_OBJECT */
76};
77
78static void smk_bu_mode(int mode, char *s)
79{
80 int i = 0;
81
82 if (mode & MAY_READ)
83 s[i++] = 'r';
84 if (mode & MAY_WRITE)
85 s[i++] = 'w';
86 if (mode & MAY_EXEC)
87 s[i++] = 'x';
88 if (mode & MAY_APPEND)
89 s[i++] = 'a';
90 if (mode & MAY_TRANSMUTE)
91 s[i++] = 't';
92 if (mode & MAY_LOCK)
93 s[i++] = 'l';
94 if (i == 0)
95 s[i++] = '-';
96 s[i] = '\0';
97}
98#endif
99
100#ifdef CONFIG_SECURITY_SMACK_BRINGUP
101static int smk_bu_note(char *note, struct smack_known *sskp,
102 struct smack_known *oskp, int mode, int rc)
103{
104 char acc[SMK_NUM_ACCESS_TYPE + 1];
105
106 if (rc <= 0)
107 return rc;
108 if (rc > SMACK_UNCONFINED_OBJECT)
109 rc = 0;
110
111 smk_bu_mode(mode, acc);
112 pr_info("Smack %s: (%s %s %s) %s\n", smk_bu_mess[rc],
113 sskp->smk_known, oskp->smk_known, acc, note);
114 return 0;
115}
116#else
117#define smk_bu_note(note, sskp, oskp, mode, RC) (RC)
118#endif
119
120#ifdef CONFIG_SECURITY_SMACK_BRINGUP
121static int smk_bu_current(char *note, struct smack_known *oskp,
122 int mode, int rc)
123{
124 struct task_smack *tsp = current_security();
125 char acc[SMK_NUM_ACCESS_TYPE + 1];
126
127 if (rc <= 0)
128 return rc;
129 if (rc > SMACK_UNCONFINED_OBJECT)
130 rc = 0;
131
132 smk_bu_mode(mode, acc);
133 pr_info("Smack %s: (%s %s %s) %s %s\n", smk_bu_mess[rc],
134 tsp->smk_task->smk_known, oskp->smk_known,
135 acc, current->comm, note);
136 return 0;
137}
138#else
139#define smk_bu_current(note, oskp, mode, RC) (RC)
140#endif
141
142#ifdef CONFIG_SECURITY_SMACK_BRINGUP
143static int smk_bu_task(struct task_struct *otp, int mode, int rc)
144{
145 struct task_smack *tsp = current_security();
146 struct smack_known *smk_task = smk_of_task_struct(otp);
147 char acc[SMK_NUM_ACCESS_TYPE + 1];
148
149 if (rc <= 0)
150 return rc;
151 if (rc > SMACK_UNCONFINED_OBJECT)
152 rc = 0;
153
154 smk_bu_mode(mode, acc);
155 pr_info("Smack %s: (%s %s %s) %s to %s\n", smk_bu_mess[rc],
156 tsp->smk_task->smk_known, smk_task->smk_known, acc,
157 current->comm, otp->comm);
158 return 0;
159}
160#else
161#define smk_bu_task(otp, mode, RC) (RC)
162#endif
163
164#ifdef CONFIG_SECURITY_SMACK_BRINGUP
165static int smk_bu_inode(struct inode *inode, int mode, int rc)
166{
167 struct task_smack *tsp = current_security();
168 struct inode_smack *isp = inode->i_security;
169 char acc[SMK_NUM_ACCESS_TYPE + 1];
170
171 if (isp->smk_flags & SMK_INODE_IMPURE)
172 pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n",
173 inode->i_sb->s_id, inode->i_ino, current->comm);
174
175 if (rc <= 0)
176 return rc;
177 if (rc > SMACK_UNCONFINED_OBJECT)
178 rc = 0;
179 if (rc == SMACK_UNCONFINED_SUBJECT &&
180 (mode & (MAY_WRITE | MAY_APPEND)))
181 isp->smk_flags |= SMK_INODE_IMPURE;
182
183 smk_bu_mode(mode, acc);
184
185 pr_info("Smack %s: (%s %s %s) inode=(%s %ld) %s\n", smk_bu_mess[rc],
186 tsp->smk_task->smk_known, isp->smk_inode->smk_known, acc,
187 inode->i_sb->s_id, inode->i_ino, current->comm);
188 return 0;
189}
190#else
191#define smk_bu_inode(inode, mode, RC) (RC)
192#endif
193
194#ifdef CONFIG_SECURITY_SMACK_BRINGUP
195static int smk_bu_file(struct file *file, int mode, int rc)
196{
197 struct task_smack *tsp = current_security();
198 struct smack_known *sskp = tsp->smk_task;
199 struct inode *inode = file_inode(file);
200 struct inode_smack *isp = inode->i_security;
201 char acc[SMK_NUM_ACCESS_TYPE + 1];
202
203 if (isp->smk_flags & SMK_INODE_IMPURE)
204 pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n",
205 inode->i_sb->s_id, inode->i_ino, current->comm);
206
207 if (rc <= 0)
208 return rc;
209 if (rc > SMACK_UNCONFINED_OBJECT)
210 rc = 0;
211
212 smk_bu_mode(mode, acc);
213 pr_info("Smack %s: (%s %s %s) file=(%s %ld %pD) %s\n", smk_bu_mess[rc],
214 sskp->smk_known, smk_of_inode(inode)->smk_known, acc,
215 inode->i_sb->s_id, inode->i_ino, file,
216 current->comm);
217 return 0;
218}
219#else
220#define smk_bu_file(file, mode, RC) (RC)
221#endif
222
223#ifdef CONFIG_SECURITY_SMACK_BRINGUP
224static int smk_bu_credfile(const struct cred *cred, struct file *file,
225 int mode, int rc)
226{
227 struct task_smack *tsp = cred->security;
228 struct smack_known *sskp = tsp->smk_task;
229 struct inode *inode = file_inode(file);
230 struct inode_smack *isp = inode->i_security;
231 char acc[SMK_NUM_ACCESS_TYPE + 1];
232
233 if (isp->smk_flags & SMK_INODE_IMPURE)
234 pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n",
235 inode->i_sb->s_id, inode->i_ino, current->comm);
236
237 if (rc <= 0)
238 return rc;
239 if (rc > SMACK_UNCONFINED_OBJECT)
240 rc = 0;
241
242 smk_bu_mode(mode, acc);
243 pr_info("Smack %s: (%s %s %s) file=(%s %ld %pD) %s\n", smk_bu_mess[rc],
244 sskp->smk_known, smk_of_inode(inode)->smk_known, acc,
245 inode->i_sb->s_id, inode->i_ino, file,
246 current->comm);
247 return 0;
248}
249#else
250#define smk_bu_credfile(cred, file, mode, RC) (RC)
251#endif
252
253/**
254 * smk_fetch - Fetch the smack label from a file.
255 * @name: type of the label (attribute)
256 * @ip: a pointer to the inode
257 * @dp: a pointer to the dentry
258 *
259 * Returns a pointer to the master list entry for the Smack label,
260 * NULL if there was no label to fetch, or an error code.
261 */
262static struct smack_known *smk_fetch(const char *name, struct inode *ip,
263 struct dentry *dp)
264{
265 int rc;
266 char *buffer;
267 struct smack_known *skp = NULL;
268
269 if (!(ip->i_opflags & IOP_XATTR))
270 return ERR_PTR(-EOPNOTSUPP);
271
272 buffer = kzalloc(SMK_LONGLABEL, GFP_KERNEL);
273 if (buffer == NULL)
274 return ERR_PTR(-ENOMEM);
275
276 rc = __vfs_getxattr(dp, ip, name, buffer, SMK_LONGLABEL);
277 if (rc < 0)
278 skp = ERR_PTR(rc);
279 else if (rc == 0)
280 skp = NULL;
281 else
282 skp = smk_import_entry(buffer, rc);
283
284 kfree(buffer);
285
286 return skp;
287}
288
289/**
290 * new_inode_smack - allocate an inode security blob
291 * @skp: a pointer to the Smack label entry to use in the blob
292 *
293 * Returns the new blob or NULL if there's no memory available
294 */
295static struct inode_smack *new_inode_smack(struct smack_known *skp)
296{
297 struct inode_smack *isp;
298
299 isp = kmem_cache_zalloc(smack_inode_cache, GFP_NOFS);
300 if (isp == NULL)
301 return NULL;
302
303 isp->smk_inode = skp;
304 isp->smk_flags = 0;
305 mutex_init(&isp->smk_lock);
306
307 return isp;
308}
309
310/**
311 * new_task_smack - allocate a task security blob
312 * @task: a pointer to the Smack label for the running task
313 * @forked: a pointer to the Smack label for the forked task
314 * @gfp: type of the memory for the allocation
315 *
316 * Returns the new blob or NULL if there's no memory available
317 */
318static struct task_smack *new_task_smack(struct smack_known *task,
319 struct smack_known *forked, gfp_t gfp)
320{
321 struct task_smack *tsp;
322
323 tsp = kzalloc(sizeof(struct task_smack), gfp);
324 if (tsp == NULL)
325 return NULL;
326
327 tsp->smk_task = task;
328 tsp->smk_forked = forked;
329 INIT_LIST_HEAD(&tsp->smk_rules);
330 INIT_LIST_HEAD(&tsp->smk_relabel);
331 mutex_init(&tsp->smk_rules_lock);
332
333 return tsp;
334}
335
336/**
337 * smk_copy_rules - copy a rule set
338 * @nhead: new rules header pointer
339 * @ohead: old rules header pointer
340 * @gfp: type of the memory for the allocation
341 *
342 * Returns 0 on success, -ENOMEM on error
343 */
344static int smk_copy_rules(struct list_head *nhead, struct list_head *ohead,
345 gfp_t gfp)
346{
347 struct smack_rule *nrp;
348 struct smack_rule *orp;
349 int rc = 0;
350
351 list_for_each_entry_rcu(orp, ohead, list) {
352 nrp = kzalloc(sizeof(struct smack_rule), gfp);
353 if (nrp == NULL) {
354 rc = -ENOMEM;
355 break;
356 }
357 *nrp = *orp;
358 list_add_rcu(&nrp->list, nhead);
359 }
360 return rc;
361}
362
363/**
364 * smk_copy_relabel - copy smk_relabel labels list
365 * @nhead: new rules header pointer
366 * @ohead: old rules header pointer
367 * @gfp: type of the memory for the allocation
368 *
369 * Returns 0 on success, -ENOMEM on error
370 */
371static int smk_copy_relabel(struct list_head *nhead, struct list_head *ohead,
372 gfp_t gfp)
373{
374 struct smack_known_list_elem *nklep;
375 struct smack_known_list_elem *oklep;
376
377 list_for_each_entry(oklep, ohead, list) {
378 nklep = kzalloc(sizeof(struct smack_known_list_elem), gfp);
379 if (nklep == NULL) {
380 smk_destroy_label_list(nhead);
381 return -ENOMEM;
382 }
383 nklep->smk_label = oklep->smk_label;
384 list_add(&nklep->list, nhead);
385 }
386
387 return 0;
388}
389
390/**
391 * smk_ptrace_mode - helper function for converting PTRACE_MODE_* into MAY_*
392 * @mode - input mode in form of PTRACE_MODE_*
393 *
394 * Returns a converted MAY_* mode usable by smack rules
395 */
396static inline unsigned int smk_ptrace_mode(unsigned int mode)
397{
398 if (mode & PTRACE_MODE_ATTACH)
399 return MAY_READWRITE;
400 if (mode & PTRACE_MODE_READ)
401 return MAY_READ;
402
403 return 0;
404}
405
406/**
407 * smk_ptrace_rule_check - helper for ptrace access
408 * @tracer: tracer process
409 * @tracee_known: label entry of the process that's about to be traced
410 * @mode: ptrace attachment mode (PTRACE_MODE_*)
411 * @func: name of the function that called us, used for audit
412 *
413 * Returns 0 on access granted, -error on error
414 */
415static int smk_ptrace_rule_check(struct task_struct *tracer,
416 struct smack_known *tracee_known,
417 unsigned int mode, const char *func)
418{
419 int rc;
420 struct smk_audit_info ad, *saip = NULL;
421 struct task_smack *tsp;
422 struct smack_known *tracer_known;
423
424 if ((mode & PTRACE_MODE_NOAUDIT) == 0) {
425 smk_ad_init(&ad, func, LSM_AUDIT_DATA_TASK);
426 smk_ad_setfield_u_tsk(&ad, tracer);
427 saip = &ad;
428 }
429
430 rcu_read_lock();
431 tsp = __task_cred(tracer)->security;
432 tracer_known = smk_of_task(tsp);
433
434 if ((mode & PTRACE_MODE_ATTACH) &&
435 (smack_ptrace_rule == SMACK_PTRACE_EXACT ||
436 smack_ptrace_rule == SMACK_PTRACE_DRACONIAN)) {
437 if (tracer_known->smk_known == tracee_known->smk_known)
438 rc = 0;
439 else if (smack_ptrace_rule == SMACK_PTRACE_DRACONIAN)
440 rc = -EACCES;
441 else if (capable(CAP_SYS_PTRACE))
442 rc = 0;
443 else
444 rc = -EACCES;
445
446 if (saip)
447 smack_log(tracer_known->smk_known,
448 tracee_known->smk_known,
449 0, rc, saip);
450
451 rcu_read_unlock();
452 return rc;
453 }
454
455 /* In case of rule==SMACK_PTRACE_DEFAULT or mode==PTRACE_MODE_READ */
456 rc = smk_tskacc(tsp, tracee_known, smk_ptrace_mode(mode), saip);
457
458 rcu_read_unlock();
459 return rc;
460}
461
462/*
463 * LSM hooks.
464 * We he, that is fun!
465 */
466
467/**
468 * smack_ptrace_access_check - Smack approval on PTRACE_ATTACH
469 * @ctp: child task pointer
470 * @mode: ptrace attachment mode (PTRACE_MODE_*)
471 *
472 * Returns 0 if access is OK, an error code otherwise
473 *
474 * Do the capability checks.
475 */
476static int smack_ptrace_access_check(struct task_struct *ctp, unsigned int mode)
477{
478 struct smack_known *skp;
479
480 skp = smk_of_task_struct(ctp);
481
482 return smk_ptrace_rule_check(current, skp, mode, __func__);
483}
484
485/**
486 * smack_ptrace_traceme - Smack approval on PTRACE_TRACEME
487 * @ptp: parent task pointer
488 *
489 * Returns 0 if access is OK, an error code otherwise
490 *
491 * Do the capability checks, and require PTRACE_MODE_ATTACH.
492 */
493static int smack_ptrace_traceme(struct task_struct *ptp)
494{
495 int rc;
496 struct smack_known *skp;
497
498 skp = smk_of_task(current_security());
499
500 rc = smk_ptrace_rule_check(ptp, skp, PTRACE_MODE_ATTACH, __func__);
501 return rc;
502}
503
504/**
505 * smack_syslog - Smack approval on syslog
506 * @type: message type
507 *
508 * Returns 0 on success, error code otherwise.
509 */
510static int smack_syslog(int typefrom_file)
511{
512 int rc = 0;
513 struct smack_known *skp = smk_of_current();
514
515 if (smack_privileged(CAP_MAC_OVERRIDE))
516 return 0;
517
518 if (smack_syslog_label != NULL && smack_syslog_label != skp)
519 rc = -EACCES;
520
521 return rc;
522}
523
524
525/*
526 * Superblock Hooks.
527 */
528
529/**
530 * smack_sb_alloc_security - allocate a superblock blob
531 * @sb: the superblock getting the blob
532 *
533 * Returns 0 on success or -ENOMEM on error.
534 */
535static int smack_sb_alloc_security(struct super_block *sb)
536{
537 struct superblock_smack *sbsp;
538
539 sbsp = kzalloc(sizeof(struct superblock_smack), GFP_KERNEL);
540
541 if (sbsp == NULL)
542 return -ENOMEM;
543
544 sbsp->smk_root = &smack_known_floor;
545 sbsp->smk_default = &smack_known_floor;
546 sbsp->smk_floor = &smack_known_floor;
547 sbsp->smk_hat = &smack_known_hat;
548 /*
549 * SMK_SB_INITIALIZED will be zero from kzalloc.
550 */
551 sb->s_security = sbsp;
552
553 return 0;
554}
555
556/**
557 * smack_sb_free_security - free a superblock blob
558 * @sb: the superblock getting the blob
559 *
560 */
561static void smack_sb_free_security(struct super_block *sb)
562{
563 kfree(sb->s_security);
564 sb->s_security = NULL;
565}
566
567/**
568 * smack_sb_copy_data - copy mount options data for processing
569 * @orig: where to start
570 * @smackopts: mount options string
571 *
572 * Returns 0 on success or -ENOMEM on error.
573 *
574 * Copy the Smack specific mount options out of the mount
575 * options list.
576 */
577static int smack_sb_copy_data(char *orig, char *smackopts)
578{
579 char *cp, *commap, *otheropts, *dp;
580
581 otheropts = (char *)get_zeroed_page(GFP_KERNEL);
582 if (otheropts == NULL)
583 return -ENOMEM;
584
585 for (cp = orig, commap = orig; commap != NULL; cp = commap + 1) {
586 if (strstr(cp, SMK_FSDEFAULT) == cp)
587 dp = smackopts;
588 else if (strstr(cp, SMK_FSFLOOR) == cp)
589 dp = smackopts;
590 else if (strstr(cp, SMK_FSHAT) == cp)
591 dp = smackopts;
592 else if (strstr(cp, SMK_FSROOT) == cp)
593 dp = smackopts;
594 else if (strstr(cp, SMK_FSTRANS) == cp)
595 dp = smackopts;
596 else
597 dp = otheropts;
598
599 commap = strchr(cp, ',');
600 if (commap != NULL)
601 *commap = '\0';
602
603 if (*dp != '\0')
604 strcat(dp, ",");
605 strcat(dp, cp);
606 }
607
608 strcpy(orig, otheropts);
609 free_page((unsigned long)otheropts);
610
611 return 0;
612}
613
614/**
615 * smack_parse_opts_str - parse Smack specific mount options
616 * @options: mount options string
617 * @opts: where to store converted mount opts
618 *
619 * Returns 0 on success or -ENOMEM on error.
620 *
621 * converts Smack specific mount options to generic security option format
622 */
623static int smack_parse_opts_str(char *options,
624 struct security_mnt_opts *opts)
625{
626 char *p;
627 char *fsdefault = NULL;
628 char *fsfloor = NULL;
629 char *fshat = NULL;
630 char *fsroot = NULL;
631 char *fstransmute = NULL;
632 int rc = -ENOMEM;
633 int num_mnt_opts = 0;
634 int token;
635
636 opts->num_mnt_opts = 0;
637
638 if (!options)
639 return 0;
640
641 while ((p = strsep(&options, ",")) != NULL) {
642 substring_t args[MAX_OPT_ARGS];
643
644 if (!*p)
645 continue;
646
647 token = match_token(p, smk_mount_tokens, args);
648
649 switch (token) {
650 case Opt_fsdefault:
651 if (fsdefault)
652 goto out_opt_err;
653 fsdefault = match_strdup(&args[0]);
654 if (!fsdefault)
655 goto out_err;
656 break;
657 case Opt_fsfloor:
658 if (fsfloor)
659 goto out_opt_err;
660 fsfloor = match_strdup(&args[0]);
661 if (!fsfloor)
662 goto out_err;
663 break;
664 case Opt_fshat:
665 if (fshat)
666 goto out_opt_err;
667 fshat = match_strdup(&args[0]);
668 if (!fshat)
669 goto out_err;
670 break;
671 case Opt_fsroot:
672 if (fsroot)
673 goto out_opt_err;
674 fsroot = match_strdup(&args[0]);
675 if (!fsroot)
676 goto out_err;
677 break;
678 case Opt_fstransmute:
679 if (fstransmute)
680 goto out_opt_err;
681 fstransmute = match_strdup(&args[0]);
682 if (!fstransmute)
683 goto out_err;
684 break;
685 default:
686 rc = -EINVAL;
687 pr_warn("Smack: unknown mount option\n");
688 goto out_err;
689 }
690 }
691
692 opts->mnt_opts = kcalloc(NUM_SMK_MNT_OPTS, sizeof(char *), GFP_KERNEL);
693 if (!opts->mnt_opts)
694 goto out_err;
695
696 opts->mnt_opts_flags = kcalloc(NUM_SMK_MNT_OPTS, sizeof(int),
697 GFP_KERNEL);
698 if (!opts->mnt_opts_flags)
699 goto out_err;
700
701 if (fsdefault) {
702 opts->mnt_opts[num_mnt_opts] = fsdefault;
703 opts->mnt_opts_flags[num_mnt_opts++] = FSDEFAULT_MNT;
704 }
705 if (fsfloor) {
706 opts->mnt_opts[num_mnt_opts] = fsfloor;
707 opts->mnt_opts_flags[num_mnt_opts++] = FSFLOOR_MNT;
708 }
709 if (fshat) {
710 opts->mnt_opts[num_mnt_opts] = fshat;
711 opts->mnt_opts_flags[num_mnt_opts++] = FSHAT_MNT;
712 }
713 if (fsroot) {
714 opts->mnt_opts[num_mnt_opts] = fsroot;
715 opts->mnt_opts_flags[num_mnt_opts++] = FSROOT_MNT;
716 }
717 if (fstransmute) {
718 opts->mnt_opts[num_mnt_opts] = fstransmute;
719 opts->mnt_opts_flags[num_mnt_opts++] = FSTRANS_MNT;
720 }
721
722 opts->num_mnt_opts = num_mnt_opts;
723 return 0;
724
725out_opt_err:
726 rc = -EINVAL;
727 pr_warn("Smack: duplicate mount options\n");
728
729out_err:
730 kfree(fsdefault);
731 kfree(fsfloor);
732 kfree(fshat);
733 kfree(fsroot);
734 kfree(fstransmute);
735 return rc;
736}
737
738/**
739 * smack_set_mnt_opts - set Smack specific mount options
740 * @sb: the file system superblock
741 * @opts: Smack mount options
742 * @kern_flags: mount option from kernel space or user space
743 * @set_kern_flags: where to store converted mount opts
744 *
745 * Returns 0 on success, an error code on failure
746 *
747 * Allow filesystems with binary mount data to explicitly set Smack mount
748 * labels.
749 */
750static int smack_set_mnt_opts(struct super_block *sb,
751 struct security_mnt_opts *opts,
752 unsigned long kern_flags,
753 unsigned long *set_kern_flags)
754{
755 struct dentry *root = sb->s_root;
756 struct inode *inode = d_backing_inode(root);
757 struct superblock_smack *sp = sb->s_security;
758 struct inode_smack *isp;
759 struct smack_known *skp;
760 int i;
761 int num_opts = opts->num_mnt_opts;
762 int transmute = 0;
763
764 if (sp->smk_flags & SMK_SB_INITIALIZED)
765 return 0;
766
767 if (!smack_privileged(CAP_MAC_ADMIN)) {
768 /*
769 * Unprivileged mounts don't get to specify Smack values.
770 */
771 if (num_opts)
772 return -EPERM;
773 /*
774 * Unprivileged mounts get root and default from the caller.
775 */
776 skp = smk_of_current();
777 sp->smk_root = skp;
778 sp->smk_default = skp;
779 /*
780 * For a handful of fs types with no user-controlled
781 * backing store it's okay to trust security labels
782 * in the filesystem. The rest are untrusted.
783 */
784 if (sb->s_user_ns != &init_user_ns &&
785 sb->s_magic != SYSFS_MAGIC && sb->s_magic != TMPFS_MAGIC &&
786 sb->s_magic != RAMFS_MAGIC) {
787 transmute = 1;
788 sp->smk_flags |= SMK_SB_UNTRUSTED;
789 }
790 }
791
792 sp->smk_flags |= SMK_SB_INITIALIZED;
793
794 for (i = 0; i < num_opts; i++) {
795 switch (opts->mnt_opts_flags[i]) {
796 case FSDEFAULT_MNT:
797 skp = smk_import_entry(opts->mnt_opts[i], 0);
798 if (IS_ERR(skp))
799 return PTR_ERR(skp);
800 sp->smk_default = skp;
801 break;
802 case FSFLOOR_MNT:
803 skp = smk_import_entry(opts->mnt_opts[i], 0);
804 if (IS_ERR(skp))
805 return PTR_ERR(skp);
806 sp->smk_floor = skp;
807 break;
808 case FSHAT_MNT:
809 skp = smk_import_entry(opts->mnt_opts[i], 0);
810 if (IS_ERR(skp))
811 return PTR_ERR(skp);
812 sp->smk_hat = skp;
813 break;
814 case FSROOT_MNT:
815 skp = smk_import_entry(opts->mnt_opts[i], 0);
816 if (IS_ERR(skp))
817 return PTR_ERR(skp);
818 sp->smk_root = skp;
819 break;
820 case FSTRANS_MNT:
821 skp = smk_import_entry(opts->mnt_opts[i], 0);
822 if (IS_ERR(skp))
823 return PTR_ERR(skp);
824 sp->smk_root = skp;
825 transmute = 1;
826 break;
827 default:
828 break;
829 }
830 }
831
832 /*
833 * Initialize the root inode.
834 */
835 isp = inode->i_security;
836 if (isp == NULL) {
837 isp = new_inode_smack(sp->smk_root);
838 if (isp == NULL)
839 return -ENOMEM;
840 inode->i_security = isp;
841 } else
842 isp->smk_inode = sp->smk_root;
843
844 if (transmute)
845 isp->smk_flags |= SMK_INODE_TRANSMUTE;
846
847 return 0;
848}
849
850/**
851 * smack_sb_kern_mount - Smack specific mount processing
852 * @sb: the file system superblock
853 * @flags: the mount flags
854 * @data: the smack mount options
855 *
856 * Returns 0 on success, an error code on failure
857 */
858static int smack_sb_kern_mount(struct super_block *sb, int flags, void *data)
859{
860 int rc = 0;
861 char *options = data;
862 struct security_mnt_opts opts;
863
864 security_init_mnt_opts(&opts);
865
866 if (!options)
867 goto out;
868
869 rc = smack_parse_opts_str(options, &opts);
870 if (rc)
871 goto out_err;
872
873out:
874 rc = smack_set_mnt_opts(sb, &opts, 0, NULL);
875
876out_err:
877 security_free_mnt_opts(&opts);
878 return rc;
879}
880
881/**
882 * smack_sb_statfs - Smack check on statfs
883 * @dentry: identifies the file system in question
884 *
885 * Returns 0 if current can read the floor of the filesystem,
886 * and error code otherwise
887 */
888static int smack_sb_statfs(struct dentry *dentry)
889{
890 struct superblock_smack *sbp = dentry->d_sb->s_security;
891 int rc;
892 struct smk_audit_info ad;
893
894 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
895 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
896
897 rc = smk_curacc(sbp->smk_floor, MAY_READ, &ad);
898 rc = smk_bu_current("statfs", sbp->smk_floor, MAY_READ, rc);
899 return rc;
900}
901
902/*
903 * BPRM hooks
904 */
905
906/**
907 * smack_bprm_set_creds - set creds for exec
908 * @bprm: the exec information
909 *
910 * Returns 0 if it gets a blob, -EPERM if exec forbidden and -ENOMEM otherwise
911 */
912static int smack_bprm_set_creds(struct linux_binprm *bprm)
913{
914 struct inode *inode = file_inode(bprm->file);
915 struct task_smack *bsp = bprm->cred->security;
916 struct inode_smack *isp;
917 struct superblock_smack *sbsp;
918 int rc;
919
920 if (bprm->called_set_creds)
921 return 0;
922
923 isp = inode->i_security;
924 if (isp->smk_task == NULL || isp->smk_task == bsp->smk_task)
925 return 0;
926
927 sbsp = inode->i_sb->s_security;
928 if ((sbsp->smk_flags & SMK_SB_UNTRUSTED) &&
929 isp->smk_task != sbsp->smk_root)
930 return 0;
931
932 if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
933 struct task_struct *tracer;
934 rc = 0;
935
936 rcu_read_lock();
937 tracer = ptrace_parent(current);
938 if (likely(tracer != NULL))
939 rc = smk_ptrace_rule_check(tracer,
940 isp->smk_task,
941 PTRACE_MODE_ATTACH,
942 __func__);
943 rcu_read_unlock();
944
945 if (rc != 0)
946 return rc;
947 } else if (bprm->unsafe)
948 return -EPERM;
949
950 bsp->smk_task = isp->smk_task;
951 bprm->per_clear |= PER_CLEAR_ON_SETID;
952
953 /* Decide if this is a secure exec. */
954 if (bsp->smk_task != bsp->smk_forked)
955 bprm->secureexec = 1;
956
957 return 0;
958}
959
960/*
961 * Inode hooks
962 */
963
964/**
965 * smack_inode_alloc_security - allocate an inode blob
966 * @inode: the inode in need of a blob
967 *
968 * Returns 0 if it gets a blob, -ENOMEM otherwise
969 */
970static int smack_inode_alloc_security(struct inode *inode)
971{
972 struct smack_known *skp = smk_of_current();
973
974 inode->i_security = new_inode_smack(skp);
975 if (inode->i_security == NULL)
976 return -ENOMEM;
977 return 0;
978}
979
980/**
981 * smack_inode_free_rcu - Free inode_smack blob from cache
982 * @head: the rcu_head for getting inode_smack pointer
983 *
984 * Call back function called from call_rcu() to free
985 * the i_security blob pointer in inode
986 */
987static void smack_inode_free_rcu(struct rcu_head *head)
988{
989 struct inode_smack *issp;
990
991 issp = container_of(head, struct inode_smack, smk_rcu);
992 kmem_cache_free(smack_inode_cache, issp);
993}
994
995/**
996 * smack_inode_free_security - free an inode blob using call_rcu()
997 * @inode: the inode with a blob
998 *
999 * Clears the blob pointer in inode using RCU
1000 */
1001static void smack_inode_free_security(struct inode *inode)
1002{
1003 struct inode_smack *issp = inode->i_security;
1004
1005 /*
1006 * The inode may still be referenced in a path walk and
1007 * a call to smack_inode_permission() can be made
1008 * after smack_inode_free_security() is called.
1009 * To avoid race condition free the i_security via RCU
1010 * and leave the current inode->i_security pointer intact.
1011 * The inode will be freed after the RCU grace period too.
1012 */
1013 call_rcu(&issp->smk_rcu, smack_inode_free_rcu);
1014}
1015
1016/**
1017 * smack_inode_init_security - copy out the smack from an inode
1018 * @inode: the newly created inode
1019 * @dir: containing directory object
1020 * @qstr: unused
1021 * @name: where to put the attribute name
1022 * @value: where to put the attribute value
1023 * @len: where to put the length of the attribute
1024 *
1025 * Returns 0 if it all works out, -ENOMEM if there's no memory
1026 */
1027static int smack_inode_init_security(struct inode *inode, struct inode *dir,
1028 const struct qstr *qstr, const char **name,
1029 void **value, size_t *len)
1030{
1031 struct inode_smack *issp = inode->i_security;
1032 struct smack_known *skp = smk_of_current();
1033 struct smack_known *isp = smk_of_inode(inode);
1034 struct smack_known *dsp = smk_of_inode(dir);
1035 int may;
1036
1037 if (name)
1038 *name = XATTR_SMACK_SUFFIX;
1039
1040 if (value && len) {
1041 rcu_read_lock();
1042 may = smk_access_entry(skp->smk_known, dsp->smk_known,
1043 &skp->smk_rules);
1044 rcu_read_unlock();
1045
1046 /*
1047 * If the access rule allows transmutation and
1048 * the directory requests transmutation then
1049 * by all means transmute.
1050 * Mark the inode as changed.
1051 */
1052 if (may > 0 && ((may & MAY_TRANSMUTE) != 0) &&
1053 smk_inode_transmutable(dir)) {
1054 isp = dsp;
1055 issp->smk_flags |= SMK_INODE_CHANGED;
1056 }
1057
1058 *value = kstrdup(isp->smk_known, GFP_NOFS);
1059 if (*value == NULL)
1060 return -ENOMEM;
1061
1062 *len = strlen(isp->smk_known);
1063 }
1064
1065 return 0;
1066}
1067
1068/**
1069 * smack_inode_link - Smack check on link
1070 * @old_dentry: the existing object
1071 * @dir: unused
1072 * @new_dentry: the new object
1073 *
1074 * Returns 0 if access is permitted, an error code otherwise
1075 */
1076static int smack_inode_link(struct dentry *old_dentry, struct inode *dir,
1077 struct dentry *new_dentry)
1078{
1079 struct smack_known *isp;
1080 struct smk_audit_info ad;
1081 int rc;
1082
1083 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1084 smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
1085
1086 isp = smk_of_inode(d_backing_inode(old_dentry));
1087 rc = smk_curacc(isp, MAY_WRITE, &ad);
1088 rc = smk_bu_inode(d_backing_inode(old_dentry), MAY_WRITE, rc);
1089
1090 if (rc == 0 && d_is_positive(new_dentry)) {
1091 isp = smk_of_inode(d_backing_inode(new_dentry));
1092 smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
1093 rc = smk_curacc(isp, MAY_WRITE, &ad);
1094 rc = smk_bu_inode(d_backing_inode(new_dentry), MAY_WRITE, rc);
1095 }
1096
1097 return rc;
1098}
1099
1100/**
1101 * smack_inode_unlink - Smack check on inode deletion
1102 * @dir: containing directory object
1103 * @dentry: file to unlink
1104 *
1105 * Returns 0 if current can write the containing directory
1106 * and the object, error code otherwise
1107 */
1108static int smack_inode_unlink(struct inode *dir, struct dentry *dentry)
1109{
1110 struct inode *ip = d_backing_inode(dentry);
1111 struct smk_audit_info ad;
1112 int rc;
1113
1114 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1115 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1116
1117 /*
1118 * You need write access to the thing you're unlinking
1119 */
1120 rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad);
1121 rc = smk_bu_inode(ip, MAY_WRITE, rc);
1122 if (rc == 0) {
1123 /*
1124 * You also need write access to the containing directory
1125 */
1126 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
1127 smk_ad_setfield_u_fs_inode(&ad, dir);
1128 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
1129 rc = smk_bu_inode(dir, MAY_WRITE, rc);
1130 }
1131 return rc;
1132}
1133
1134/**
1135 * smack_inode_rmdir - Smack check on directory deletion
1136 * @dir: containing directory object
1137 * @dentry: directory to unlink
1138 *
1139 * Returns 0 if current can write the containing directory
1140 * and the directory, error code otherwise
1141 */
1142static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry)
1143{
1144 struct smk_audit_info ad;
1145 int rc;
1146
1147 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1148 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1149
1150 /*
1151 * You need write access to the thing you're removing
1152 */
1153 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1154 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1155 if (rc == 0) {
1156 /*
1157 * You also need write access to the containing directory
1158 */
1159 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
1160 smk_ad_setfield_u_fs_inode(&ad, dir);
1161 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
1162 rc = smk_bu_inode(dir, MAY_WRITE, rc);
1163 }
1164
1165 return rc;
1166}
1167
1168/**
1169 * smack_inode_rename - Smack check on rename
1170 * @old_inode: unused
1171 * @old_dentry: the old object
1172 * @new_inode: unused
1173 * @new_dentry: the new object
1174 *
1175 * Read and write access is required on both the old and
1176 * new directories.
1177 *
1178 * Returns 0 if access is permitted, an error code otherwise
1179 */
1180static int smack_inode_rename(struct inode *old_inode,
1181 struct dentry *old_dentry,
1182 struct inode *new_inode,
1183 struct dentry *new_dentry)
1184{
1185 int rc;
1186 struct smack_known *isp;
1187 struct smk_audit_info ad;
1188
1189 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1190 smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
1191
1192 isp = smk_of_inode(d_backing_inode(old_dentry));
1193 rc = smk_curacc(isp, MAY_READWRITE, &ad);
1194 rc = smk_bu_inode(d_backing_inode(old_dentry), MAY_READWRITE, rc);
1195
1196 if (rc == 0 && d_is_positive(new_dentry)) {
1197 isp = smk_of_inode(d_backing_inode(new_dentry));
1198 smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
1199 rc = smk_curacc(isp, MAY_READWRITE, &ad);
1200 rc = smk_bu_inode(d_backing_inode(new_dentry), MAY_READWRITE, rc);
1201 }
1202 return rc;
1203}
1204
1205/**
1206 * smack_inode_permission - Smack version of permission()
1207 * @inode: the inode in question
1208 * @mask: the access requested
1209 *
1210 * This is the important Smack hook.
1211 *
1212 * Returns 0 if access is permitted, -EACCES otherwise
1213 */
1214static int smack_inode_permission(struct inode *inode, int mask)
1215{
1216 struct superblock_smack *sbsp = inode->i_sb->s_security;
1217 struct smk_audit_info ad;
1218 int no_block = mask & MAY_NOT_BLOCK;
1219 int rc;
1220
1221 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
1222 /*
1223 * No permission to check. Existence test. Yup, it's there.
1224 */
1225 if (mask == 0)
1226 return 0;
1227
1228 if (sbsp->smk_flags & SMK_SB_UNTRUSTED) {
1229 if (smk_of_inode(inode) != sbsp->smk_root)
1230 return -EACCES;
1231 }
1232
1233 /* May be droppable after audit */
1234 if (no_block)
1235 return -ECHILD;
1236 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
1237 smk_ad_setfield_u_fs_inode(&ad, inode);
1238 rc = smk_curacc(smk_of_inode(inode), mask, &ad);
1239 rc = smk_bu_inode(inode, mask, rc);
1240 return rc;
1241}
1242
1243/**
1244 * smack_inode_setattr - Smack check for setting attributes
1245 * @dentry: the object
1246 * @iattr: for the force flag
1247 *
1248 * Returns 0 if access is permitted, an error code otherwise
1249 */
1250static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr)
1251{
1252 struct smk_audit_info ad;
1253 int rc;
1254
1255 /*
1256 * Need to allow for clearing the setuid bit.
1257 */
1258 if (iattr->ia_valid & ATTR_FORCE)
1259 return 0;
1260 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1261 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1262
1263 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1264 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1265 return rc;
1266}
1267
1268/**
1269 * smack_inode_getattr - Smack check for getting attributes
1270 * @mnt: vfsmount of the object
1271 * @dentry: the object
1272 *
1273 * Returns 0 if access is permitted, an error code otherwise
1274 */
1275static int smack_inode_getattr(const struct path *path)
1276{
1277 struct smk_audit_info ad;
1278 struct inode *inode = d_backing_inode(path->dentry);
1279 int rc;
1280
1281 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1282 smk_ad_setfield_u_fs_path(&ad, *path);
1283 rc = smk_curacc(smk_of_inode(inode), MAY_READ, &ad);
1284 rc = smk_bu_inode(inode, MAY_READ, rc);
1285 return rc;
1286}
1287
1288/**
1289 * smack_inode_setxattr - Smack check for setting xattrs
1290 * @dentry: the object
1291 * @name: name of the attribute
1292 * @value: value of the attribute
1293 * @size: size of the value
1294 * @flags: unused
1295 *
1296 * This protects the Smack attribute explicitly.
1297 *
1298 * Returns 0 if access is permitted, an error code otherwise
1299 */
1300static int smack_inode_setxattr(struct dentry *dentry, const char *name,
1301 const void *value, size_t size, int flags)
1302{
1303 struct smk_audit_info ad;
1304 struct smack_known *skp;
1305 int check_priv = 0;
1306 int check_import = 0;
1307 int check_star = 0;
1308 int rc = 0;
1309
1310 /*
1311 * Check label validity here so import won't fail in post_setxattr
1312 */
1313 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
1314 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
1315 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) {
1316 check_priv = 1;
1317 check_import = 1;
1318 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
1319 strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1320 check_priv = 1;
1321 check_import = 1;
1322 check_star = 1;
1323 } else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
1324 check_priv = 1;
1325 if (size != TRANS_TRUE_SIZE ||
1326 strncmp(value, TRANS_TRUE, TRANS_TRUE_SIZE) != 0)
1327 rc = -EINVAL;
1328 } else
1329 rc = cap_inode_setxattr(dentry, name, value, size, flags);
1330
1331 if (check_priv && !smack_privileged(CAP_MAC_ADMIN))
1332 rc = -EPERM;
1333
1334 if (rc == 0 && check_import) {
1335 skp = size ? smk_import_entry(value, size) : NULL;
1336 if (IS_ERR(skp))
1337 rc = PTR_ERR(skp);
1338 else if (skp == NULL || (check_star &&
1339 (skp == &smack_known_star || skp == &smack_known_web)))
1340 rc = -EINVAL;
1341 }
1342
1343 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1344 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1345
1346 if (rc == 0) {
1347 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1348 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1349 }
1350
1351 return rc;
1352}
1353
1354/**
1355 * smack_inode_post_setxattr - Apply the Smack update approved above
1356 * @dentry: object
1357 * @name: attribute name
1358 * @value: attribute value
1359 * @size: attribute size
1360 * @flags: unused
1361 *
1362 * Set the pointer in the inode blob to the entry found
1363 * in the master label list.
1364 */
1365static void smack_inode_post_setxattr(struct dentry *dentry, const char *name,
1366 const void *value, size_t size, int flags)
1367{
1368 struct smack_known *skp;
1369 struct inode_smack *isp = d_backing_inode(dentry)->i_security;
1370
1371 if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
1372 isp->smk_flags |= SMK_INODE_TRANSMUTE;
1373 return;
1374 }
1375
1376 if (strcmp(name, XATTR_NAME_SMACK) == 0) {
1377 skp = smk_import_entry(value, size);
1378 if (!IS_ERR(skp))
1379 isp->smk_inode = skp;
1380 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0) {
1381 skp = smk_import_entry(value, size);
1382 if (!IS_ERR(skp))
1383 isp->smk_task = skp;
1384 } else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1385 skp = smk_import_entry(value, size);
1386 if (!IS_ERR(skp))
1387 isp->smk_mmap = skp;
1388 }
1389
1390 return;
1391}
1392
1393/**
1394 * smack_inode_getxattr - Smack check on getxattr
1395 * @dentry: the object
1396 * @name: unused
1397 *
1398 * Returns 0 if access is permitted, an error code otherwise
1399 */
1400static int smack_inode_getxattr(struct dentry *dentry, const char *name)
1401{
1402 struct smk_audit_info ad;
1403 int rc;
1404
1405 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1406 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1407
1408 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_READ, &ad);
1409 rc = smk_bu_inode(d_backing_inode(dentry), MAY_READ, rc);
1410 return rc;
1411}
1412
1413/**
1414 * smack_inode_removexattr - Smack check on removexattr
1415 * @dentry: the object
1416 * @name: name of the attribute
1417 *
1418 * Removing the Smack attribute requires CAP_MAC_ADMIN
1419 *
1420 * Returns 0 if access is permitted, an error code otherwise
1421 */
1422static int smack_inode_removexattr(struct dentry *dentry, const char *name)
1423{
1424 struct inode_smack *isp;
1425 struct smk_audit_info ad;
1426 int rc = 0;
1427
1428 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
1429 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
1430 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
1431 strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
1432 strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0 ||
1433 strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1434 if (!smack_privileged(CAP_MAC_ADMIN))
1435 rc = -EPERM;
1436 } else
1437 rc = cap_inode_removexattr(dentry, name);
1438
1439 if (rc != 0)
1440 return rc;
1441
1442 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1443 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1444
1445 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1446 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1447 if (rc != 0)
1448 return rc;
1449
1450 isp = d_backing_inode(dentry)->i_security;
1451 /*
1452 * Don't do anything special for these.
1453 * XATTR_NAME_SMACKIPIN
1454 * XATTR_NAME_SMACKIPOUT
1455 */
1456 if (strcmp(name, XATTR_NAME_SMACK) == 0) {
1457 struct super_block *sbp = dentry->d_sb;
1458 struct superblock_smack *sbsp = sbp->s_security;
1459
1460 isp->smk_inode = sbsp->smk_default;
1461 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0)
1462 isp->smk_task = NULL;
1463 else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0)
1464 isp->smk_mmap = NULL;
1465 else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0)
1466 isp->smk_flags &= ~SMK_INODE_TRANSMUTE;
1467
1468 return 0;
1469}
1470
1471/**
1472 * smack_inode_getsecurity - get smack xattrs
1473 * @inode: the object
1474 * @name: attribute name
1475 * @buffer: where to put the result
1476 * @alloc: duplicate memory
1477 *
1478 * Returns the size of the attribute or an error code
1479 */
1480static int smack_inode_getsecurity(struct inode *inode,
1481 const char *name, void **buffer,
1482 bool alloc)
1483{
1484 struct socket_smack *ssp;
1485 struct socket *sock;
1486 struct super_block *sbp;
1487 struct inode *ip = (struct inode *)inode;
1488 struct smack_known *isp;
1489
1490 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0)
1491 isp = smk_of_inode(inode);
1492 else {
1493 /*
1494 * The rest of the Smack xattrs are only on sockets.
1495 */
1496 sbp = ip->i_sb;
1497 if (sbp->s_magic != SOCKFS_MAGIC)
1498 return -EOPNOTSUPP;
1499
1500 sock = SOCKET_I(ip);
1501 if (sock == NULL || sock->sk == NULL)
1502 return -EOPNOTSUPP;
1503
1504 ssp = sock->sk->sk_security;
1505
1506 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
1507 isp = ssp->smk_in;
1508 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0)
1509 isp = ssp->smk_out;
1510 else
1511 return -EOPNOTSUPP;
1512 }
1513
1514 if (alloc) {
1515 *buffer = kstrdup(isp->smk_known, GFP_KERNEL);
1516 if (*buffer == NULL)
1517 return -ENOMEM;
1518 }
1519
1520 return strlen(isp->smk_known);
1521}
1522
1523
1524/**
1525 * smack_inode_listsecurity - list the Smack attributes
1526 * @inode: the object
1527 * @buffer: where they go
1528 * @buffer_size: size of buffer
1529 */
1530static int smack_inode_listsecurity(struct inode *inode, char *buffer,
1531 size_t buffer_size)
1532{
1533 int len = sizeof(XATTR_NAME_SMACK);
1534
1535 if (buffer != NULL && len <= buffer_size)
1536 memcpy(buffer, XATTR_NAME_SMACK, len);
1537
1538 return len;
1539}
1540
1541/**
1542 * smack_inode_getsecid - Extract inode's security id
1543 * @inode: inode to extract the info from
1544 * @secid: where result will be saved
1545 */
1546static void smack_inode_getsecid(struct inode *inode, u32 *secid)
1547{
1548 struct inode_smack *isp = inode->i_security;
1549
1550 *secid = isp->smk_inode->smk_secid;
1551}
1552
1553/*
1554 * File Hooks
1555 */
1556
1557/*
1558 * There is no smack_file_permission hook
1559 *
1560 * Should access checks be done on each read or write?
1561 * UNICOS and SELinux say yes.
1562 * Trusted Solaris, Trusted Irix, and just about everyone else says no.
1563 *
1564 * I'll say no for now. Smack does not do the frequent
1565 * label changing that SELinux does.
1566 */
1567
1568/**
1569 * smack_file_alloc_security - assign a file security blob
1570 * @file: the object
1571 *
1572 * The security blob for a file is a pointer to the master
1573 * label list, so no allocation is done.
1574 *
1575 * f_security is the owner security information. It
1576 * isn't used on file access checks, it's for send_sigio.
1577 *
1578 * Returns 0
1579 */
1580static int smack_file_alloc_security(struct file *file)
1581{
1582 struct smack_known *skp = smk_of_current();
1583
1584 file->f_security = skp;
1585 return 0;
1586}
1587
1588/**
1589 * smack_file_free_security - clear a file security blob
1590 * @file: the object
1591 *
1592 * The security blob for a file is a pointer to the master
1593 * label list, so no memory is freed.
1594 */
1595static void smack_file_free_security(struct file *file)
1596{
1597 file->f_security = NULL;
1598}
1599
1600/**
1601 * smack_file_ioctl - Smack check on ioctls
1602 * @file: the object
1603 * @cmd: what to do
1604 * @arg: unused
1605 *
1606 * Relies heavily on the correct use of the ioctl command conventions.
1607 *
1608 * Returns 0 if allowed, error code otherwise
1609 */
1610static int smack_file_ioctl(struct file *file, unsigned int cmd,
1611 unsigned long arg)
1612{
1613 int rc = 0;
1614 struct smk_audit_info ad;
1615 struct inode *inode = file_inode(file);
1616
1617 if (unlikely(IS_PRIVATE(inode)))
1618 return 0;
1619
1620 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1621 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1622
1623 if (_IOC_DIR(cmd) & _IOC_WRITE) {
1624 rc = smk_curacc(smk_of_inode(inode), MAY_WRITE, &ad);
1625 rc = smk_bu_file(file, MAY_WRITE, rc);
1626 }
1627
1628 if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ)) {
1629 rc = smk_curacc(smk_of_inode(inode), MAY_READ, &ad);
1630 rc = smk_bu_file(file, MAY_READ, rc);
1631 }
1632
1633 return rc;
1634}
1635
1636/**
1637 * smack_file_lock - Smack check on file locking
1638 * @file: the object
1639 * @cmd: unused
1640 *
1641 * Returns 0 if current has lock access, error code otherwise
1642 */
1643static int smack_file_lock(struct file *file, unsigned int cmd)
1644{
1645 struct smk_audit_info ad;
1646 int rc;
1647 struct inode *inode = file_inode(file);
1648
1649 if (unlikely(IS_PRIVATE(inode)))
1650 return 0;
1651
1652 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1653 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1654 rc = smk_curacc(smk_of_inode(inode), MAY_LOCK, &ad);
1655 rc = smk_bu_file(file, MAY_LOCK, rc);
1656 return rc;
1657}
1658
1659/**
1660 * smack_file_fcntl - Smack check on fcntl
1661 * @file: the object
1662 * @cmd: what action to check
1663 * @arg: unused
1664 *
1665 * Generally these operations are harmless.
1666 * File locking operations present an obvious mechanism
1667 * for passing information, so they require write access.
1668 *
1669 * Returns 0 if current has access, error code otherwise
1670 */
1671static int smack_file_fcntl(struct file *file, unsigned int cmd,
1672 unsigned long arg)
1673{
1674 struct smk_audit_info ad;
1675 int rc = 0;
1676 struct inode *inode = file_inode(file);
1677
1678 if (unlikely(IS_PRIVATE(inode)))
1679 return 0;
1680
1681 switch (cmd) {
1682 case F_GETLK:
1683 break;
1684 case F_SETLK:
1685 case F_SETLKW:
1686 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1687 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1688 rc = smk_curacc(smk_of_inode(inode), MAY_LOCK, &ad);
1689 rc = smk_bu_file(file, MAY_LOCK, rc);
1690 break;
1691 case F_SETOWN:
1692 case F_SETSIG:
1693 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1694 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1695 rc = smk_curacc(smk_of_inode(inode), MAY_WRITE, &ad);
1696 rc = smk_bu_file(file, MAY_WRITE, rc);
1697 break;
1698 default:
1699 break;
1700 }
1701
1702 return rc;
1703}
1704
1705/**
1706 * smack_mmap_file :
1707 * Check permissions for a mmap operation. The @file may be NULL, e.g.
1708 * if mapping anonymous memory.
1709 * @file contains the file structure for file to map (may be NULL).
1710 * @reqprot contains the protection requested by the application.
1711 * @prot contains the protection that will be applied by the kernel.
1712 * @flags contains the operational flags.
1713 * Return 0 if permission is granted.
1714 */
1715static int smack_mmap_file(struct file *file,
1716 unsigned long reqprot, unsigned long prot,
1717 unsigned long flags)
1718{
1719 struct smack_known *skp;
1720 struct smack_known *mkp;
1721 struct smack_rule *srp;
1722 struct task_smack *tsp;
1723 struct smack_known *okp;
1724 struct inode_smack *isp;
1725 struct superblock_smack *sbsp;
1726 int may;
1727 int mmay;
1728 int tmay;
1729 int rc;
1730
1731 if (file == NULL)
1732 return 0;
1733
1734 if (unlikely(IS_PRIVATE(file_inode(file))))
1735 return 0;
1736
1737 isp = file_inode(file)->i_security;
1738 if (isp->smk_mmap == NULL)
1739 return 0;
1740 sbsp = file_inode(file)->i_sb->s_security;
1741 if (sbsp->smk_flags & SMK_SB_UNTRUSTED &&
1742 isp->smk_mmap != sbsp->smk_root)
1743 return -EACCES;
1744 mkp = isp->smk_mmap;
1745
1746 tsp = current_security();
1747 skp = smk_of_current();
1748 rc = 0;
1749
1750 rcu_read_lock();
1751 /*
1752 * For each Smack rule associated with the subject
1753 * label verify that the SMACK64MMAP also has access
1754 * to that rule's object label.
1755 */
1756 list_for_each_entry_rcu(srp, &skp->smk_rules, list) {
1757 okp = srp->smk_object;
1758 /*
1759 * Matching labels always allows access.
1760 */
1761 if (mkp->smk_known == okp->smk_known)
1762 continue;
1763 /*
1764 * If there is a matching local rule take
1765 * that into account as well.
1766 */
1767 may = smk_access_entry(srp->smk_subject->smk_known,
1768 okp->smk_known,
1769 &tsp->smk_rules);
1770 if (may == -ENOENT)
1771 may = srp->smk_access;
1772 else
1773 may &= srp->smk_access;
1774 /*
1775 * If may is zero the SMACK64MMAP subject can't
1776 * possibly have less access.
1777 */
1778 if (may == 0)
1779 continue;
1780
1781 /*
1782 * Fetch the global list entry.
1783 * If there isn't one a SMACK64MMAP subject
1784 * can't have as much access as current.
1785 */
1786 mmay = smk_access_entry(mkp->smk_known, okp->smk_known,
1787 &mkp->smk_rules);
1788 if (mmay == -ENOENT) {
1789 rc = -EACCES;
1790 break;
1791 }
1792 /*
1793 * If there is a local entry it modifies the
1794 * potential access, too.
1795 */
1796 tmay = smk_access_entry(mkp->smk_known, okp->smk_known,
1797 &tsp->smk_rules);
1798 if (tmay != -ENOENT)
1799 mmay &= tmay;
1800
1801 /*
1802 * If there is any access available to current that is
1803 * not available to a SMACK64MMAP subject
1804 * deny access.
1805 */
1806 if ((may | mmay) != mmay) {
1807 rc = -EACCES;
1808 break;
1809 }
1810 }
1811
1812 rcu_read_unlock();
1813
1814 return rc;
1815}
1816
1817/**
1818 * smack_file_set_fowner - set the file security blob value
1819 * @file: object in question
1820 *
1821 */
1822static void smack_file_set_fowner(struct file *file)
1823{
1824 file->f_security = smk_of_current();
1825}
1826
1827/**
1828 * smack_file_send_sigiotask - Smack on sigio
1829 * @tsk: The target task
1830 * @fown: the object the signal come from
1831 * @signum: unused
1832 *
1833 * Allow a privileged task to get signals even if it shouldn't
1834 *
1835 * Returns 0 if a subject with the object's smack could
1836 * write to the task, an error code otherwise.
1837 */
1838static int smack_file_send_sigiotask(struct task_struct *tsk,
1839 struct fown_struct *fown, int signum)
1840{
1841 struct smack_known *skp;
1842 struct smack_known *tkp = smk_of_task(tsk->cred->security);
1843 struct file *file;
1844 int rc;
1845 struct smk_audit_info ad;
1846
1847 /*
1848 * struct fown_struct is never outside the context of a struct file
1849 */
1850 file = container_of(fown, struct file, f_owner);
1851
1852 /* we don't log here as rc can be overriden */
1853 skp = file->f_security;
1854 rc = smk_access(skp, tkp, MAY_DELIVER, NULL);
1855 rc = smk_bu_note("sigiotask", skp, tkp, MAY_DELIVER, rc);
1856 if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE))
1857 rc = 0;
1858
1859 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1860 smk_ad_setfield_u_tsk(&ad, tsk);
1861 smack_log(skp->smk_known, tkp->smk_known, MAY_DELIVER, rc, &ad);
1862 return rc;
1863}
1864
1865/**
1866 * smack_file_receive - Smack file receive check
1867 * @file: the object
1868 *
1869 * Returns 0 if current has access, error code otherwise
1870 */
1871static int smack_file_receive(struct file *file)
1872{
1873 int rc;
1874 int may = 0;
1875 struct smk_audit_info ad;
1876 struct inode *inode = file_inode(file);
1877 struct socket *sock;
1878 struct task_smack *tsp;
1879 struct socket_smack *ssp;
1880
1881 if (unlikely(IS_PRIVATE(inode)))
1882 return 0;
1883
1884 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1885 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1886
1887 if (inode->i_sb->s_magic == SOCKFS_MAGIC) {
1888 sock = SOCKET_I(inode);
1889 ssp = sock->sk->sk_security;
1890 tsp = current_security();
1891 /*
1892 * If the receiving process can't write to the
1893 * passed socket or if the passed socket can't
1894 * write to the receiving process don't accept
1895 * the passed socket.
1896 */
1897 rc = smk_access(tsp->smk_task, ssp->smk_out, MAY_WRITE, &ad);
1898 rc = smk_bu_file(file, may, rc);
1899 if (rc < 0)
1900 return rc;
1901 rc = smk_access(ssp->smk_in, tsp->smk_task, MAY_WRITE, &ad);
1902 rc = smk_bu_file(file, may, rc);
1903 return rc;
1904 }
1905 /*
1906 * This code relies on bitmasks.
1907 */
1908 if (file->f_mode & FMODE_READ)
1909 may = MAY_READ;
1910 if (file->f_mode & FMODE_WRITE)
1911 may |= MAY_WRITE;
1912
1913 rc = smk_curacc(smk_of_inode(inode), may, &ad);
1914 rc = smk_bu_file(file, may, rc);
1915 return rc;
1916}
1917
1918/**
1919 * smack_file_open - Smack dentry open processing
1920 * @file: the object
1921 * @cred: task credential
1922 *
1923 * Set the security blob in the file structure.
1924 * Allow the open only if the task has read access. There are
1925 * many read operations (e.g. fstat) that you can do with an
1926 * fd even if you have the file open write-only.
1927 *
1928 * Returns 0
1929 */
1930static int smack_file_open(struct file *file, const struct cred *cred)
1931{
1932 struct task_smack *tsp = cred->security;
1933 struct inode *inode = file_inode(file);
1934 struct smk_audit_info ad;
1935 int rc;
1936
1937 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1938 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1939 rc = smk_tskacc(tsp, smk_of_inode(inode), MAY_READ, &ad);
1940 rc = smk_bu_credfile(cred, file, MAY_READ, rc);
1941
1942 return rc;
1943}
1944
1945/*
1946 * Task hooks
1947 */
1948
1949/**
1950 * smack_cred_alloc_blank - "allocate" blank task-level security credentials
1951 * @new: the new credentials
1952 * @gfp: the atomicity of any memory allocations
1953 *
1954 * Prepare a blank set of credentials for modification. This must allocate all
1955 * the memory the LSM module might require such that cred_transfer() can
1956 * complete without error.
1957 */
1958static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp)
1959{
1960 struct task_smack *tsp;
1961
1962 tsp = new_task_smack(NULL, NULL, gfp);
1963 if (tsp == NULL)
1964 return -ENOMEM;
1965
1966 cred->security = tsp;
1967
1968 return 0;
1969}
1970
1971
1972/**
1973 * smack_cred_free - "free" task-level security credentials
1974 * @cred: the credentials in question
1975 *
1976 */
1977static void smack_cred_free(struct cred *cred)
1978{
1979 struct task_smack *tsp = cred->security;
1980 struct smack_rule *rp;
1981 struct list_head *l;
1982 struct list_head *n;
1983
1984 if (tsp == NULL)
1985 return;
1986 cred->security = NULL;
1987
1988 smk_destroy_label_list(&tsp->smk_relabel);
1989
1990 list_for_each_safe(l, n, &tsp->smk_rules) {
1991 rp = list_entry(l, struct smack_rule, list);
1992 list_del(&rp->list);
1993 kfree(rp);
1994 }
1995 kfree(tsp);
1996}
1997
1998/**
1999 * smack_cred_prepare - prepare new set of credentials for modification
2000 * @new: the new credentials
2001 * @old: the original credentials
2002 * @gfp: the atomicity of any memory allocations
2003 *
2004 * Prepare a new set of credentials for modification.
2005 */
2006static int smack_cred_prepare(struct cred *new, const struct cred *old,
2007 gfp_t gfp)
2008{
2009 struct task_smack *old_tsp = old->security;
2010 struct task_smack *new_tsp;
2011 int rc;
2012
2013 new_tsp = new_task_smack(old_tsp->smk_task, old_tsp->smk_task, gfp);
2014 if (new_tsp == NULL)
2015 return -ENOMEM;
2016
2017 new->security = new_tsp;
2018
2019 rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp);
2020 if (rc != 0)
2021 return rc;
2022
2023 rc = smk_copy_relabel(&new_tsp->smk_relabel, &old_tsp->smk_relabel,
2024 gfp);
2025 if (rc != 0)
2026 return rc;
2027
2028 return 0;
2029}
2030
2031/**
2032 * smack_cred_transfer - Transfer the old credentials to the new credentials
2033 * @new: the new credentials
2034 * @old: the original credentials
2035 *
2036 * Fill in a set of blank credentials from another set of credentials.
2037 */
2038static void smack_cred_transfer(struct cred *new, const struct cred *old)
2039{
2040 struct task_smack *old_tsp = old->security;
2041 struct task_smack *new_tsp = new->security;
2042
2043 new_tsp->smk_task = old_tsp->smk_task;
2044 new_tsp->smk_forked = old_tsp->smk_task;
2045 mutex_init(&new_tsp->smk_rules_lock);
2046 INIT_LIST_HEAD(&new_tsp->smk_rules);
2047
2048
2049 /* cbs copy rule list */
2050}
2051
2052/**
2053 * smack_cred_getsecid - get the secid corresponding to a creds structure
2054 * @c: the object creds
2055 * @secid: where to put the result
2056 *
2057 * Sets the secid to contain a u32 version of the smack label.
2058 */
2059static void smack_cred_getsecid(const struct cred *c, u32 *secid)
2060{
2061 struct smack_known *skp;
2062
2063 rcu_read_lock();
2064 skp = smk_of_task(c->security);
2065 *secid = skp->smk_secid;
2066 rcu_read_unlock();
2067}
2068
2069/**
2070 * smack_kernel_act_as - Set the subjective context in a set of credentials
2071 * @new: points to the set of credentials to be modified.
2072 * @secid: specifies the security ID to be set
2073 *
2074 * Set the security data for a kernel service.
2075 */
2076static int smack_kernel_act_as(struct cred *new, u32 secid)
2077{
2078 struct task_smack *new_tsp = new->security;
2079
2080 new_tsp->smk_task = smack_from_secid(secid);
2081 return 0;
2082}
2083
2084/**
2085 * smack_kernel_create_files_as - Set the file creation label in a set of creds
2086 * @new: points to the set of credentials to be modified
2087 * @inode: points to the inode to use as a reference
2088 *
2089 * Set the file creation context in a set of credentials to the same
2090 * as the objective context of the specified inode
2091 */
2092static int smack_kernel_create_files_as(struct cred *new,
2093 struct inode *inode)
2094{
2095 struct inode_smack *isp = inode->i_security;
2096 struct task_smack *tsp = new->security;
2097
2098 tsp->smk_forked = isp->smk_inode;
2099 tsp->smk_task = tsp->smk_forked;
2100 return 0;
2101}
2102
2103/**
2104 * smk_curacc_on_task - helper to log task related access
2105 * @p: the task object
2106 * @access: the access requested
2107 * @caller: name of the calling function for audit
2108 *
2109 * Return 0 if access is permitted
2110 */
2111static int smk_curacc_on_task(struct task_struct *p, int access,
2112 const char *caller)
2113{
2114 struct smk_audit_info ad;
2115 struct smack_known *skp = smk_of_task_struct(p);
2116 int rc;
2117
2118 smk_ad_init(&ad, caller, LSM_AUDIT_DATA_TASK);
2119 smk_ad_setfield_u_tsk(&ad, p);
2120 rc = smk_curacc(skp, access, &ad);
2121 rc = smk_bu_task(p, access, rc);
2122 return rc;
2123}
2124
2125/**
2126 * smack_task_setpgid - Smack check on setting pgid
2127 * @p: the task object
2128 * @pgid: unused
2129 *
2130 * Return 0 if write access is permitted
2131 */
2132static int smack_task_setpgid(struct task_struct *p, pid_t pgid)
2133{
2134 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2135}
2136
2137/**
2138 * smack_task_getpgid - Smack access check for getpgid
2139 * @p: the object task
2140 *
2141 * Returns 0 if current can read the object task, error code otherwise
2142 */
2143static int smack_task_getpgid(struct task_struct *p)
2144{
2145 return smk_curacc_on_task(p, MAY_READ, __func__);
2146}
2147
2148/**
2149 * smack_task_getsid - Smack access check for getsid
2150 * @p: the object task
2151 *
2152 * Returns 0 if current can read the object task, error code otherwise
2153 */
2154static int smack_task_getsid(struct task_struct *p)
2155{
2156 return smk_curacc_on_task(p, MAY_READ, __func__);
2157}
2158
2159/**
2160 * smack_task_getsecid - get the secid of the task
2161 * @p: the object task
2162 * @secid: where to put the result
2163 *
2164 * Sets the secid to contain a u32 version of the smack label.
2165 */
2166static void smack_task_getsecid(struct task_struct *p, u32 *secid)
2167{
2168 struct smack_known *skp = smk_of_task_struct(p);
2169
2170 *secid = skp->smk_secid;
2171}
2172
2173/**
2174 * smack_task_setnice - Smack check on setting nice
2175 * @p: the task object
2176 * @nice: unused
2177 *
2178 * Return 0 if write access is permitted
2179 */
2180static int smack_task_setnice(struct task_struct *p, int nice)
2181{
2182 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2183}
2184
2185/**
2186 * smack_task_setioprio - Smack check on setting ioprio
2187 * @p: the task object
2188 * @ioprio: unused
2189 *
2190 * Return 0 if write access is permitted
2191 */
2192static int smack_task_setioprio(struct task_struct *p, int ioprio)
2193{
2194 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2195}
2196
2197/**
2198 * smack_task_getioprio - Smack check on reading ioprio
2199 * @p: the task object
2200 *
2201 * Return 0 if read access is permitted
2202 */
2203static int smack_task_getioprio(struct task_struct *p)
2204{
2205 return smk_curacc_on_task(p, MAY_READ, __func__);
2206}
2207
2208/**
2209 * smack_task_setscheduler - Smack check on setting scheduler
2210 * @p: the task object
2211 * @policy: unused
2212 * @lp: unused
2213 *
2214 * Return 0 if read access is permitted
2215 */
2216static int smack_task_setscheduler(struct task_struct *p)
2217{
2218 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2219}
2220
2221/**
2222 * smack_task_getscheduler - Smack check on reading scheduler
2223 * @p: the task object
2224 *
2225 * Return 0 if read access is permitted
2226 */
2227static int smack_task_getscheduler(struct task_struct *p)
2228{
2229 return smk_curacc_on_task(p, MAY_READ, __func__);
2230}
2231
2232/**
2233 * smack_task_movememory - Smack check on moving memory
2234 * @p: the task object
2235 *
2236 * Return 0 if write access is permitted
2237 */
2238static int smack_task_movememory(struct task_struct *p)
2239{
2240 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2241}
2242
2243/**
2244 * smack_task_kill - Smack check on signal delivery
2245 * @p: the task object
2246 * @info: unused
2247 * @sig: unused
2248 * @cred: identifies the cred to use in lieu of current's
2249 *
2250 * Return 0 if write access is permitted
2251 *
2252 */
2253static int smack_task_kill(struct task_struct *p, struct siginfo *info,
2254 int sig, const struct cred *cred)
2255{
2256 struct smk_audit_info ad;
2257 struct smack_known *skp;
2258 struct smack_known *tkp = smk_of_task_struct(p);
2259 int rc;
2260
2261 if (!sig)
2262 return 0; /* null signal; existence test */
2263
2264 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
2265 smk_ad_setfield_u_tsk(&ad, p);
2266 /*
2267 * Sending a signal requires that the sender
2268 * can write the receiver.
2269 */
2270 if (cred == NULL) {
2271 rc = smk_curacc(tkp, MAY_DELIVER, &ad);
2272 rc = smk_bu_task(p, MAY_DELIVER, rc);
2273 return rc;
2274 }
2275 /*
2276 * If the cred isn't NULL we're dealing with some USB IO
2277 * specific behavior. This is not clean. For one thing
2278 * we can't take privilege into account.
2279 */
2280 skp = smk_of_task(cred->security);
2281 rc = smk_access(skp, tkp, MAY_DELIVER, &ad);
2282 rc = smk_bu_note("USB signal", skp, tkp, MAY_DELIVER, rc);
2283 return rc;
2284}
2285
2286/**
2287 * smack_task_to_inode - copy task smack into the inode blob
2288 * @p: task to copy from
2289 * @inode: inode to copy to
2290 *
2291 * Sets the smack pointer in the inode security blob
2292 */
2293static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
2294{
2295 struct inode_smack *isp = inode->i_security;
2296 struct smack_known *skp = smk_of_task_struct(p);
2297
2298 isp->smk_inode = skp;
2299}
2300
2301/*
2302 * Socket hooks.
2303 */
2304
2305/**
2306 * smack_sk_alloc_security - Allocate a socket blob
2307 * @sk: the socket
2308 * @family: unused
2309 * @gfp_flags: memory allocation flags
2310 *
2311 * Assign Smack pointers to current
2312 *
2313 * Returns 0 on success, -ENOMEM is there's no memory
2314 */
2315static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags)
2316{
2317 struct smack_known *skp = smk_of_current();
2318 struct socket_smack *ssp;
2319
2320 ssp = kzalloc(sizeof(struct socket_smack), gfp_flags);
2321 if (ssp == NULL)
2322 return -ENOMEM;
2323
2324 /*
2325 * Sockets created by kernel threads receive web label.
2326 */
2327 if (unlikely(current->flags & PF_KTHREAD)) {
2328 ssp->smk_in = &smack_known_web;
2329 ssp->smk_out = &smack_known_web;
2330 } else {
2331 ssp->smk_in = skp;
2332 ssp->smk_out = skp;
2333 }
2334 ssp->smk_packet = NULL;
2335
2336 sk->sk_security = ssp;
2337
2338 return 0;
2339}
2340
2341/**
2342 * smack_sk_free_security - Free a socket blob
2343 * @sk: the socket
2344 *
2345 * Clears the blob pointer
2346 */
2347static void smack_sk_free_security(struct sock *sk)
2348{
2349#ifdef SMACK_IPV6_PORT_LABELING
2350 struct smk_port_label *spp;
2351
2352 if (sk->sk_family == PF_INET6) {
2353 rcu_read_lock();
2354 list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
2355 if (spp->smk_sock != sk)
2356 continue;
2357 spp->smk_can_reuse = 1;
2358 break;
2359 }
2360 rcu_read_unlock();
2361 }
2362#endif
2363 kfree(sk->sk_security);
2364}
2365
2366/**
2367* smack_ipv4host_label - check host based restrictions
2368* @sip: the object end
2369*
2370* looks for host based access restrictions
2371*
2372* This version will only be appropriate for really small sets of single label
2373* hosts. The caller is responsible for ensuring that the RCU read lock is
2374* taken before calling this function.
2375*
2376* Returns the label of the far end or NULL if it's not special.
2377*/
2378static struct smack_known *smack_ipv4host_label(struct sockaddr_in *sip)
2379{
2380 struct smk_net4addr *snp;
2381 struct in_addr *siap = &sip->sin_addr;
2382
2383 if (siap->s_addr == 0)
2384 return NULL;
2385
2386 list_for_each_entry_rcu(snp, &smk_net4addr_list, list)
2387 /*
2388 * we break after finding the first match because
2389 * the list is sorted from longest to shortest mask
2390 * so we have found the most specific match
2391 */
2392 if (snp->smk_host.s_addr ==
2393 (siap->s_addr & snp->smk_mask.s_addr))
2394 return snp->smk_label;
2395
2396 return NULL;
2397}
2398
2399#if IS_ENABLED(CONFIG_IPV6)
2400/*
2401 * smk_ipv6_localhost - Check for local ipv6 host address
2402 * @sip: the address
2403 *
2404 * Returns boolean true if this is the localhost address
2405 */
2406static bool smk_ipv6_localhost(struct sockaddr_in6 *sip)
2407{
2408 __be16 *be16p = (__be16 *)&sip->sin6_addr;
2409 __be32 *be32p = (__be32 *)&sip->sin6_addr;
2410
2411 if (be32p[0] == 0 && be32p[1] == 0 && be32p[2] == 0 && be16p[6] == 0 &&
2412 ntohs(be16p[7]) == 1)
2413 return true;
2414 return false;
2415}
2416
2417/**
2418* smack_ipv6host_label - check host based restrictions
2419* @sip: the object end
2420*
2421* looks for host based access restrictions
2422*
2423* This version will only be appropriate for really small sets of single label
2424* hosts. The caller is responsible for ensuring that the RCU read lock is
2425* taken before calling this function.
2426*
2427* Returns the label of the far end or NULL if it's not special.
2428*/
2429static struct smack_known *smack_ipv6host_label(struct sockaddr_in6 *sip)
2430{
2431 struct smk_net6addr *snp;
2432 struct in6_addr *sap = &sip->sin6_addr;
2433 int i;
2434 int found = 0;
2435
2436 /*
2437 * It's local. Don't look for a host label.
2438 */
2439 if (smk_ipv6_localhost(sip))
2440 return NULL;
2441
2442 list_for_each_entry_rcu(snp, &smk_net6addr_list, list) {
2443 /*
2444 * If the label is NULL the entry has
2445 * been renounced. Ignore it.
2446 */
2447 if (snp->smk_label == NULL)
2448 continue;
2449 /*
2450 * we break after finding the first match because
2451 * the list is sorted from longest to shortest mask
2452 * so we have found the most specific match
2453 */
2454 for (found = 1, i = 0; i < 8; i++) {
2455 if ((sap->s6_addr16[i] & snp->smk_mask.s6_addr16[i]) !=
2456 snp->smk_host.s6_addr16[i]) {
2457 found = 0;
2458 break;
2459 }
2460 }
2461 if (found)
2462 return snp->smk_label;
2463 }
2464
2465 return NULL;
2466}
2467#endif /* CONFIG_IPV6 */
2468
2469/**
2470 * smack_netlabel - Set the secattr on a socket
2471 * @sk: the socket
2472 * @labeled: socket label scheme
2473 *
2474 * Convert the outbound smack value (smk_out) to a
2475 * secattr and attach it to the socket.
2476 *
2477 * Returns 0 on success or an error code
2478 */
2479static int smack_netlabel(struct sock *sk, int labeled)
2480{
2481 struct smack_known *skp;
2482 struct socket_smack *ssp = sk->sk_security;
2483 int rc = 0;
2484
2485 /*
2486 * Usually the netlabel code will handle changing the
2487 * packet labeling based on the label.
2488 * The case of a single label host is different, because
2489 * a single label host should never get a labeled packet
2490 * even though the label is usually associated with a packet
2491 * label.
2492 */
2493 local_bh_disable();
2494 bh_lock_sock_nested(sk);
2495
2496 if (ssp->smk_out == smack_net_ambient ||
2497 labeled == SMACK_UNLABELED_SOCKET)
2498 netlbl_sock_delattr(sk);
2499 else {
2500 skp = ssp->smk_out;
2501 rc = netlbl_sock_setattr(sk, sk->sk_family, &skp->smk_netlabel);
2502 }
2503
2504 bh_unlock_sock(sk);
2505 local_bh_enable();
2506
2507 return rc;
2508}
2509
2510/**
2511 * smack_netlbel_send - Set the secattr on a socket and perform access checks
2512 * @sk: the socket
2513 * @sap: the destination address
2514 *
2515 * Set the correct secattr for the given socket based on the destination
2516 * address and perform any outbound access checks needed.
2517 *
2518 * Returns 0 on success or an error code.
2519 *
2520 */
2521static int smack_netlabel_send(struct sock *sk, struct sockaddr_in *sap)
2522{
2523 struct smack_known *skp;
2524 int rc;
2525 int sk_lbl;
2526 struct smack_known *hkp;
2527 struct socket_smack *ssp = sk->sk_security;
2528 struct smk_audit_info ad;
2529
2530 rcu_read_lock();
2531 hkp = smack_ipv4host_label(sap);
2532 if (hkp != NULL) {
2533#ifdef CONFIG_AUDIT
2534 struct lsm_network_audit net;
2535
2536 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
2537 ad.a.u.net->family = sap->sin_family;
2538 ad.a.u.net->dport = sap->sin_port;
2539 ad.a.u.net->v4info.daddr = sap->sin_addr.s_addr;
2540#endif
2541 sk_lbl = SMACK_UNLABELED_SOCKET;
2542 skp = ssp->smk_out;
2543 rc = smk_access(skp, hkp, MAY_WRITE, &ad);
2544 rc = smk_bu_note("IPv4 host check", skp, hkp, MAY_WRITE, rc);
2545 } else {
2546 sk_lbl = SMACK_CIPSO_SOCKET;
2547 rc = 0;
2548 }
2549 rcu_read_unlock();
2550 if (rc != 0)
2551 return rc;
2552
2553 return smack_netlabel(sk, sk_lbl);
2554}
2555
2556#if IS_ENABLED(CONFIG_IPV6)
2557/**
2558 * smk_ipv6_check - check Smack access
2559 * @subject: subject Smack label
2560 * @object: object Smack label
2561 * @address: address
2562 * @act: the action being taken
2563 *
2564 * Check an IPv6 access
2565 */
2566static int smk_ipv6_check(struct smack_known *subject,
2567 struct smack_known *object,
2568 struct sockaddr_in6 *address, int act)
2569{
2570#ifdef CONFIG_AUDIT
2571 struct lsm_network_audit net;
2572#endif
2573 struct smk_audit_info ad;
2574 int rc;
2575
2576#ifdef CONFIG_AUDIT
2577 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
2578 ad.a.u.net->family = PF_INET6;
2579 ad.a.u.net->dport = ntohs(address->sin6_port);
2580 if (act == SMK_RECEIVING)
2581 ad.a.u.net->v6info.saddr = address->sin6_addr;
2582 else
2583 ad.a.u.net->v6info.daddr = address->sin6_addr;
2584#endif
2585 rc = smk_access(subject, object, MAY_WRITE, &ad);
2586 rc = smk_bu_note("IPv6 check", subject, object, MAY_WRITE, rc);
2587 return rc;
2588}
2589#endif /* CONFIG_IPV6 */
2590
2591#ifdef SMACK_IPV6_PORT_LABELING
2592/**
2593 * smk_ipv6_port_label - Smack port access table management
2594 * @sock: socket
2595 * @address: address
2596 *
2597 * Create or update the port list entry
2598 */
2599static void smk_ipv6_port_label(struct socket *sock, struct sockaddr *address)
2600{
2601 struct sock *sk = sock->sk;
2602 struct sockaddr_in6 *addr6;
2603 struct socket_smack *ssp = sock->sk->sk_security;
2604 struct smk_port_label *spp;
2605 unsigned short port = 0;
2606
2607 if (address == NULL) {
2608 /*
2609 * This operation is changing the Smack information
2610 * on the bound socket. Take the changes to the port
2611 * as well.
2612 */
2613 rcu_read_lock();
2614 list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
2615 if (sk != spp->smk_sock)
2616 continue;
2617 spp->smk_in = ssp->smk_in;
2618 spp->smk_out = ssp->smk_out;
2619 rcu_read_unlock();
2620 return;
2621 }
2622 /*
2623 * A NULL address is only used for updating existing
2624 * bound entries. If there isn't one, it's OK.
2625 */
2626 rcu_read_unlock();
2627 return;
2628 }
2629
2630 addr6 = (struct sockaddr_in6 *)address;
2631 port = ntohs(addr6->sin6_port);
2632 /*
2633 * This is a special case that is safely ignored.
2634 */
2635 if (port == 0)
2636 return;
2637
2638 /*
2639 * Look for an existing port list entry.
2640 * This is an indication that a port is getting reused.
2641 */
2642 rcu_read_lock();
2643 list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
2644 if (spp->smk_port != port || spp->smk_sock_type != sock->type)
2645 continue;
2646 if (spp->smk_can_reuse != 1) {
2647 rcu_read_unlock();
2648 return;
2649 }
2650 spp->smk_port = port;
2651 spp->smk_sock = sk;
2652 spp->smk_in = ssp->smk_in;
2653 spp->smk_out = ssp->smk_out;
2654 spp->smk_can_reuse = 0;
2655 rcu_read_unlock();
2656 return;
2657 }
2658 rcu_read_unlock();
2659 /*
2660 * A new port entry is required.
2661 */
2662 spp = kzalloc(sizeof(*spp), GFP_KERNEL);
2663 if (spp == NULL)
2664 return;
2665
2666 spp->smk_port = port;
2667 spp->smk_sock = sk;
2668 spp->smk_in = ssp->smk_in;
2669 spp->smk_out = ssp->smk_out;
2670 spp->smk_sock_type = sock->type;
2671 spp->smk_can_reuse = 0;
2672
2673 mutex_lock(&smack_ipv6_lock);
2674 list_add_rcu(&spp->list, &smk_ipv6_port_list);
2675 mutex_unlock(&smack_ipv6_lock);
2676 return;
2677}
2678
2679/**
2680 * smk_ipv6_port_check - check Smack port access
2681 * @sock: socket
2682 * @address: address
2683 *
2684 * Create or update the port list entry
2685 */
2686static int smk_ipv6_port_check(struct sock *sk, struct sockaddr_in6 *address,
2687 int act)
2688{
2689 struct smk_port_label *spp;
2690 struct socket_smack *ssp = sk->sk_security;
2691 struct smack_known *skp = NULL;
2692 unsigned short port;
2693 struct smack_known *object;
2694
2695 if (act == SMK_RECEIVING) {
2696 skp = smack_ipv6host_label(address);
2697 object = ssp->smk_in;
2698 } else {
2699 skp = ssp->smk_out;
2700 object = smack_ipv6host_label(address);
2701 }
2702
2703 /*
2704 * The other end is a single label host.
2705 */
2706 if (skp != NULL && object != NULL)
2707 return smk_ipv6_check(skp, object, address, act);
2708 if (skp == NULL)
2709 skp = smack_net_ambient;
2710 if (object == NULL)
2711 object = smack_net_ambient;
2712
2713 /*
2714 * It's remote, so port lookup does no good.
2715 */
2716 if (!smk_ipv6_localhost(address))
2717 return smk_ipv6_check(skp, object, address, act);
2718
2719 /*
2720 * It's local so the send check has to have passed.
2721 */
2722 if (act == SMK_RECEIVING)
2723 return 0;
2724
2725 port = ntohs(address->sin6_port);
2726 rcu_read_lock();
2727 list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
2728 if (spp->smk_port != port || spp->smk_sock_type != sk->sk_type)
2729 continue;
2730 object = spp->smk_in;
2731 if (act == SMK_CONNECTING)
2732 ssp->smk_packet = spp->smk_out;
2733 break;
2734 }
2735 rcu_read_unlock();
2736
2737 return smk_ipv6_check(skp, object, address, act);
2738}
2739#endif /* SMACK_IPV6_PORT_LABELING */
2740
2741/**
2742 * smack_inode_setsecurity - set smack xattrs
2743 * @inode: the object
2744 * @name: attribute name
2745 * @value: attribute value
2746 * @size: size of the attribute
2747 * @flags: unused
2748 *
2749 * Sets the named attribute in the appropriate blob
2750 *
2751 * Returns 0 on success, or an error code
2752 */
2753static int smack_inode_setsecurity(struct inode *inode, const char *name,
2754 const void *value, size_t size, int flags)
2755{
2756 struct smack_known *skp;
2757 struct inode_smack *nsp = inode->i_security;
2758 struct socket_smack *ssp;
2759 struct socket *sock;
2760 int rc = 0;
2761
2762 if (value == NULL || size > SMK_LONGLABEL || size == 0)
2763 return -EINVAL;
2764
2765 skp = smk_import_entry(value, size);
2766 if (IS_ERR(skp))
2767 return PTR_ERR(skp);
2768
2769 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
2770 nsp->smk_inode = skp;
2771 nsp->smk_flags |= SMK_INODE_INSTANT;
2772 return 0;
2773 }
2774 /*
2775 * The rest of the Smack xattrs are only on sockets.
2776 */
2777 if (inode->i_sb->s_magic != SOCKFS_MAGIC)
2778 return -EOPNOTSUPP;
2779
2780 sock = SOCKET_I(inode);
2781 if (sock == NULL || sock->sk == NULL)
2782 return -EOPNOTSUPP;
2783
2784 ssp = sock->sk->sk_security;
2785
2786 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
2787 ssp->smk_in = skp;
2788 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) {
2789 ssp->smk_out = skp;
2790 if (sock->sk->sk_family == PF_INET) {
2791 rc = smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
2792 if (rc != 0)
2793 printk(KERN_WARNING
2794 "Smack: \"%s\" netlbl error %d.\n",
2795 __func__, -rc);
2796 }
2797 } else
2798 return -EOPNOTSUPP;
2799
2800#ifdef SMACK_IPV6_PORT_LABELING
2801 if (sock->sk->sk_family == PF_INET6)
2802 smk_ipv6_port_label(sock, NULL);
2803#endif
2804
2805 return 0;
2806}
2807
2808/**
2809 * smack_socket_post_create - finish socket setup
2810 * @sock: the socket
2811 * @family: protocol family
2812 * @type: unused
2813 * @protocol: unused
2814 * @kern: unused
2815 *
2816 * Sets the netlabel information on the socket
2817 *
2818 * Returns 0 on success, and error code otherwise
2819 */
2820static int smack_socket_post_create(struct socket *sock, int family,
2821 int type, int protocol, int kern)
2822{
2823 struct socket_smack *ssp;
2824
2825 if (sock->sk == NULL)
2826 return 0;
2827
2828 /*
2829 * Sockets created by kernel threads receive web label.
2830 */
2831 if (unlikely(current->flags & PF_KTHREAD)) {
2832 ssp = sock->sk->sk_security;
2833 ssp->smk_in = &smack_known_web;
2834 ssp->smk_out = &smack_known_web;
2835 }
2836
2837 if (family != PF_INET)
2838 return 0;
2839 /*
2840 * Set the outbound netlbl.
2841 */
2842 return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
2843}
2844
2845#ifdef SMACK_IPV6_PORT_LABELING
2846/**
2847 * smack_socket_bind - record port binding information.
2848 * @sock: the socket
2849 * @address: the port address
2850 * @addrlen: size of the address
2851 *
2852 * Records the label bound to a port.
2853 *
2854 * Returns 0
2855 */
2856static int smack_socket_bind(struct socket *sock, struct sockaddr *address,
2857 int addrlen)
2858{
2859 if (sock->sk != NULL && sock->sk->sk_family == PF_INET6)
2860 smk_ipv6_port_label(sock, address);
2861 return 0;
2862}
2863#endif /* SMACK_IPV6_PORT_LABELING */
2864
2865/**
2866 * smack_socket_connect - connect access check
2867 * @sock: the socket
2868 * @sap: the other end
2869 * @addrlen: size of sap
2870 *
2871 * Verifies that a connection may be possible
2872 *
2873 * Returns 0 on success, and error code otherwise
2874 */
2875static int smack_socket_connect(struct socket *sock, struct sockaddr *sap,
2876 int addrlen)
2877{
2878 int rc = 0;
2879#if IS_ENABLED(CONFIG_IPV6)
2880 struct sockaddr_in6 *sip = (struct sockaddr_in6 *)sap;
2881#endif
2882#ifdef SMACK_IPV6_SECMARK_LABELING
2883 struct smack_known *rsp;
2884 struct socket_smack *ssp;
2885#endif
2886
2887 if (sock->sk == NULL)
2888 return 0;
2889
2890#ifdef SMACK_IPV6_SECMARK_LABELING
2891 ssp = sock->sk->sk_security;
2892#endif
2893
2894 switch (sock->sk->sk_family) {
2895 case PF_INET:
2896 if (addrlen < sizeof(struct sockaddr_in))
2897 return -EINVAL;
2898 rc = smack_netlabel_send(sock->sk, (struct sockaddr_in *)sap);
2899 break;
2900 case PF_INET6:
2901 if (addrlen < sizeof(struct sockaddr_in6))
2902 return -EINVAL;
2903#ifdef SMACK_IPV6_SECMARK_LABELING
2904 rsp = smack_ipv6host_label(sip);
2905 if (rsp != NULL)
2906 rc = smk_ipv6_check(ssp->smk_out, rsp, sip,
2907 SMK_CONNECTING);
2908#endif
2909#ifdef SMACK_IPV6_PORT_LABELING
2910 rc = smk_ipv6_port_check(sock->sk, sip, SMK_CONNECTING);
2911#endif
2912 break;
2913 }
2914 return rc;
2915}
2916
2917/**
2918 * smack_flags_to_may - convert S_ to MAY_ values
2919 * @flags: the S_ value
2920 *
2921 * Returns the equivalent MAY_ value
2922 */
2923static int smack_flags_to_may(int flags)
2924{
2925 int may = 0;
2926
2927 if (flags & S_IRUGO)
2928 may |= MAY_READ;
2929 if (flags & S_IWUGO)
2930 may |= MAY_WRITE;
2931 if (flags & S_IXUGO)
2932 may |= MAY_EXEC;
2933
2934 return may;
2935}
2936
2937/**
2938 * smack_msg_msg_alloc_security - Set the security blob for msg_msg
2939 * @msg: the object
2940 *
2941 * Returns 0
2942 */
2943static int smack_msg_msg_alloc_security(struct msg_msg *msg)
2944{
2945 struct smack_known *skp = smk_of_current();
2946
2947 msg->security = skp;
2948 return 0;
2949}
2950
2951/**
2952 * smack_msg_msg_free_security - Clear the security blob for msg_msg
2953 * @msg: the object
2954 *
2955 * Clears the blob pointer
2956 */
2957static void smack_msg_msg_free_security(struct msg_msg *msg)
2958{
2959 msg->security = NULL;
2960}
2961
2962/**
2963 * smack_of_ipc - the smack pointer for the ipc
2964 * @isp: the object
2965 *
2966 * Returns a pointer to the smack value
2967 */
2968static struct smack_known *smack_of_ipc(struct kern_ipc_perm *isp)
2969{
2970 return (struct smack_known *)isp->security;
2971}
2972
2973/**
2974 * smack_ipc_alloc_security - Set the security blob for ipc
2975 * @isp: the object
2976 *
2977 * Returns 0
2978 */
2979static int smack_ipc_alloc_security(struct kern_ipc_perm *isp)
2980{
2981 struct smack_known *skp = smk_of_current();
2982
2983 isp->security = skp;
2984 return 0;
2985}
2986
2987/**
2988 * smack_ipc_free_security - Clear the security blob for ipc
2989 * @isp: the object
2990 *
2991 * Clears the blob pointer
2992 */
2993static void smack_ipc_free_security(struct kern_ipc_perm *isp)
2994{
2995 isp->security = NULL;
2996}
2997
2998/**
2999 * smk_curacc_shm : check if current has access on shm
3000 * @isp : the object
3001 * @access : access requested
3002 *
3003 * Returns 0 if current has the requested access, error code otherwise
3004 */
3005static int smk_curacc_shm(struct kern_ipc_perm *isp, int access)
3006{
3007 struct smack_known *ssp = smack_of_ipc(isp);
3008 struct smk_audit_info ad;
3009 int rc;
3010
3011#ifdef CONFIG_AUDIT
3012 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
3013 ad.a.u.ipc_id = isp->id;
3014#endif
3015 rc = smk_curacc(ssp, access, &ad);
3016 rc = smk_bu_current("shm", ssp, access, rc);
3017 return rc;
3018}
3019
3020/**
3021 * smack_shm_associate - Smack access check for shm
3022 * @isp: the object
3023 * @shmflg: access requested
3024 *
3025 * Returns 0 if current has the requested access, error code otherwise
3026 */
3027static int smack_shm_associate(struct kern_ipc_perm *isp, int shmflg)
3028{
3029 int may;
3030
3031 may = smack_flags_to_may(shmflg);
3032 return smk_curacc_shm(isp, may);
3033}
3034
3035/**
3036 * smack_shm_shmctl - Smack access check for shm
3037 * @isp: the object
3038 * @cmd: what it wants to do
3039 *
3040 * Returns 0 if current has the requested access, error code otherwise
3041 */
3042static int smack_shm_shmctl(struct kern_ipc_perm *isp, int cmd)
3043{
3044 int may;
3045
3046 switch (cmd) {
3047 case IPC_STAT:
3048 case SHM_STAT:
3049 case SHM_STAT_ANY:
3050 may = MAY_READ;
3051 break;
3052 case IPC_SET:
3053 case SHM_LOCK:
3054 case SHM_UNLOCK:
3055 case IPC_RMID:
3056 may = MAY_READWRITE;
3057 break;
3058 case IPC_INFO:
3059 case SHM_INFO:
3060 /*
3061 * System level information.
3062 */
3063 return 0;
3064 default:
3065 return -EINVAL;
3066 }
3067 return smk_curacc_shm(isp, may);
3068}
3069
3070/**
3071 * smack_shm_shmat - Smack access for shmat
3072 * @isp: the object
3073 * @shmaddr: unused
3074 * @shmflg: access requested
3075 *
3076 * Returns 0 if current has the requested access, error code otherwise
3077 */
3078static int smack_shm_shmat(struct kern_ipc_perm *ipc, char __user *shmaddr,
3079 int shmflg)
3080{
3081 int may;
3082
3083 may = smack_flags_to_may(shmflg);
3084 return smk_curacc_shm(ipc, may);
3085}
3086
3087/**
3088 * smk_curacc_sem : check if current has access on sem
3089 * @isp : the object
3090 * @access : access requested
3091 *
3092 * Returns 0 if current has the requested access, error code otherwise
3093 */
3094static int smk_curacc_sem(struct kern_ipc_perm *isp, int access)
3095{
3096 struct smack_known *ssp = smack_of_ipc(isp);
3097 struct smk_audit_info ad;
3098 int rc;
3099
3100#ifdef CONFIG_AUDIT
3101 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
3102 ad.a.u.ipc_id = isp->id;
3103#endif
3104 rc = smk_curacc(ssp, access, &ad);
3105 rc = smk_bu_current("sem", ssp, access, rc);
3106 return rc;
3107}
3108
3109/**
3110 * smack_sem_associate - Smack access check for sem
3111 * @isp: the object
3112 * @semflg: access requested
3113 *
3114 * Returns 0 if current has the requested access, error code otherwise
3115 */
3116static int smack_sem_associate(struct kern_ipc_perm *isp, int semflg)
3117{
3118 int may;
3119
3120 may = smack_flags_to_may(semflg);
3121 return smk_curacc_sem(isp, may);
3122}
3123
3124/**
3125 * smack_sem_shmctl - Smack access check for sem
3126 * @isp: the object
3127 * @cmd: what it wants to do
3128 *
3129 * Returns 0 if current has the requested access, error code otherwise
3130 */
3131static int smack_sem_semctl(struct kern_ipc_perm *isp, int cmd)
3132{
3133 int may;
3134
3135 switch (cmd) {
3136 case GETPID:
3137 case GETNCNT:
3138 case GETZCNT:
3139 case GETVAL:
3140 case GETALL:
3141 case IPC_STAT:
3142 case SEM_STAT:
3143 case SEM_STAT_ANY:
3144 may = MAY_READ;
3145 break;
3146 case SETVAL:
3147 case SETALL:
3148 case IPC_RMID:
3149 case IPC_SET:
3150 may = MAY_READWRITE;
3151 break;
3152 case IPC_INFO:
3153 case SEM_INFO:
3154 /*
3155 * System level information
3156 */
3157 return 0;
3158 default:
3159 return -EINVAL;
3160 }
3161
3162 return smk_curacc_sem(isp, may);
3163}
3164
3165/**
3166 * smack_sem_semop - Smack checks of semaphore operations
3167 * @isp: the object
3168 * @sops: unused
3169 * @nsops: unused
3170 * @alter: unused
3171 *
3172 * Treated as read and write in all cases.
3173 *
3174 * Returns 0 if access is allowed, error code otherwise
3175 */
3176static int smack_sem_semop(struct kern_ipc_perm *isp, struct sembuf *sops,
3177 unsigned nsops, int alter)
3178{
3179 return smk_curacc_sem(isp, MAY_READWRITE);
3180}
3181
3182/**
3183 * smk_curacc_msq : helper to check if current has access on msq
3184 * @isp : the msq
3185 * @access : access requested
3186 *
3187 * return 0 if current has access, error otherwise
3188 */
3189static int smk_curacc_msq(struct kern_ipc_perm *isp, int access)
3190{
3191 struct smack_known *msp = smack_of_ipc(isp);
3192 struct smk_audit_info ad;
3193 int rc;
3194
3195#ifdef CONFIG_AUDIT
3196 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
3197 ad.a.u.ipc_id = isp->id;
3198#endif
3199 rc = smk_curacc(msp, access, &ad);
3200 rc = smk_bu_current("msq", msp, access, rc);
3201 return rc;
3202}
3203
3204/**
3205 * smack_msg_queue_associate - Smack access check for msg_queue
3206 * @isp: the object
3207 * @msqflg: access requested
3208 *
3209 * Returns 0 if current has the requested access, error code otherwise
3210 */
3211static int smack_msg_queue_associate(struct kern_ipc_perm *isp, int msqflg)
3212{
3213 int may;
3214
3215 may = smack_flags_to_may(msqflg);
3216 return smk_curacc_msq(isp, may);
3217}
3218
3219/**
3220 * smack_msg_queue_msgctl - Smack access check for msg_queue
3221 * @isp: the object
3222 * @cmd: what it wants to do
3223 *
3224 * Returns 0 if current has the requested access, error code otherwise
3225 */
3226static int smack_msg_queue_msgctl(struct kern_ipc_perm *isp, int cmd)
3227{
3228 int may;
3229
3230 switch (cmd) {
3231 case IPC_STAT:
3232 case MSG_STAT:
3233 case MSG_STAT_ANY:
3234 may = MAY_READ;
3235 break;
3236 case IPC_SET:
3237 case IPC_RMID:
3238 may = MAY_READWRITE;
3239 break;
3240 case IPC_INFO:
3241 case MSG_INFO:
3242 /*
3243 * System level information
3244 */
3245 return 0;
3246 default:
3247 return -EINVAL;
3248 }
3249
3250 return smk_curacc_msq(isp, may);
3251}
3252
3253/**
3254 * smack_msg_queue_msgsnd - Smack access check for msg_queue
3255 * @isp: the object
3256 * @msg: unused
3257 * @msqflg: access requested
3258 *
3259 * Returns 0 if current has the requested access, error code otherwise
3260 */
3261static int smack_msg_queue_msgsnd(struct kern_ipc_perm *isp, struct msg_msg *msg,
3262 int msqflg)
3263{
3264 int may;
3265
3266 may = smack_flags_to_may(msqflg);
3267 return smk_curacc_msq(isp, may);
3268}
3269
3270/**
3271 * smack_msg_queue_msgsnd - Smack access check for msg_queue
3272 * @isp: the object
3273 * @msg: unused
3274 * @target: unused
3275 * @type: unused
3276 * @mode: unused
3277 *
3278 * Returns 0 if current has read and write access, error code otherwise
3279 */
3280static int smack_msg_queue_msgrcv(struct kern_ipc_perm *isp, struct msg_msg *msg,
3281 struct task_struct *target, long type, int mode)
3282{
3283 return smk_curacc_msq(isp, MAY_READWRITE);
3284}
3285
3286/**
3287 * smack_ipc_permission - Smack access for ipc_permission()
3288 * @ipp: the object permissions
3289 * @flag: access requested
3290 *
3291 * Returns 0 if current has read and write access, error code otherwise
3292 */
3293static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag)
3294{
3295 struct smack_known *iskp = ipp->security;
3296 int may = smack_flags_to_may(flag);
3297 struct smk_audit_info ad;
3298 int rc;
3299
3300#ifdef CONFIG_AUDIT
3301 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
3302 ad.a.u.ipc_id = ipp->id;
3303#endif
3304 rc = smk_curacc(iskp, may, &ad);
3305 rc = smk_bu_current("svipc", iskp, may, rc);
3306 return rc;
3307}
3308
3309/**
3310 * smack_ipc_getsecid - Extract smack security id
3311 * @ipp: the object permissions
3312 * @secid: where result will be saved
3313 */
3314static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid)
3315{
3316 struct smack_known *iskp = ipp->security;
3317
3318 *secid = iskp->smk_secid;
3319}
3320
3321/**
3322 * smack_d_instantiate - Make sure the blob is correct on an inode
3323 * @opt_dentry: dentry where inode will be attached
3324 * @inode: the object
3325 *
3326 * Set the inode's security blob if it hasn't been done already.
3327 */
3328static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
3329{
3330 struct super_block *sbp;
3331 struct superblock_smack *sbsp;
3332 struct inode_smack *isp;
3333 struct smack_known *skp;
3334 struct smack_known *ckp = smk_of_current();
3335 struct smack_known *final;
3336 char trattr[TRANS_TRUE_SIZE];
3337 int transflag = 0;
3338 int rc;
3339 struct dentry *dp;
3340
3341 if (inode == NULL)
3342 return;
3343
3344 isp = inode->i_security;
3345
3346 mutex_lock(&isp->smk_lock);
3347 /*
3348 * If the inode is already instantiated
3349 * take the quick way out
3350 */
3351 if (isp->smk_flags & SMK_INODE_INSTANT)
3352 goto unlockandout;
3353
3354 sbp = inode->i_sb;
3355 sbsp = sbp->s_security;
3356 /*
3357 * We're going to use the superblock default label
3358 * if there's no label on the file.
3359 */
3360 final = sbsp->smk_default;
3361
3362 /*
3363 * If this is the root inode the superblock
3364 * may be in the process of initialization.
3365 * If that is the case use the root value out
3366 * of the superblock.
3367 */
3368 if (opt_dentry->d_parent == opt_dentry) {
3369 switch (sbp->s_magic) {
3370 case CGROUP_SUPER_MAGIC:
3371 case CGROUP2_SUPER_MAGIC:
3372 /*
3373 * The cgroup filesystem is never mounted,
3374 * so there's no opportunity to set the mount
3375 * options.
3376 */
3377 sbsp->smk_root = &smack_known_star;
3378 sbsp->smk_default = &smack_known_star;
3379 isp->smk_inode = sbsp->smk_root;
3380 break;
3381 case TMPFS_MAGIC:
3382 /*
3383 * What about shmem/tmpfs anonymous files with dentry
3384 * obtained from d_alloc_pseudo()?
3385 */
3386 isp->smk_inode = smk_of_current();
3387 break;
3388 case PIPEFS_MAGIC:
3389 isp->smk_inode = smk_of_current();
3390 break;
3391 case SOCKFS_MAGIC:
3392 /*
3393 * Socket access is controlled by the socket
3394 * structures associated with the task involved.
3395 */
3396 isp->smk_inode = &smack_known_star;
3397 break;
3398 default:
3399 isp->smk_inode = sbsp->smk_root;
3400 break;
3401 }
3402 isp->smk_flags |= SMK_INODE_INSTANT;
3403 goto unlockandout;
3404 }
3405
3406 /*
3407 * This is pretty hackish.
3408 * Casey says that we shouldn't have to do
3409 * file system specific code, but it does help
3410 * with keeping it simple.
3411 */
3412 switch (sbp->s_magic) {
3413 case SMACK_MAGIC:
3414 case CGROUP_SUPER_MAGIC:
3415 case CGROUP2_SUPER_MAGIC:
3416 /*
3417 * Casey says that it's a little embarrassing
3418 * that the smack file system doesn't do
3419 * extended attributes.
3420 *
3421 * Cgroupfs is special
3422 */
3423 final = &smack_known_star;
3424 break;
3425 case DEVPTS_SUPER_MAGIC:
3426 /*
3427 * devpts seems content with the label of the task.
3428 * Programs that change smack have to treat the
3429 * pty with respect.
3430 */
3431 final = ckp;
3432 break;
3433 case PROC_SUPER_MAGIC:
3434 /*
3435 * Casey says procfs appears not to care.
3436 * The superblock default suffices.
3437 */
3438 break;
3439 case TMPFS_MAGIC:
3440 /*
3441 * Device labels should come from the filesystem,
3442 * but watch out, because they're volitile,
3443 * getting recreated on every reboot.
3444 */
3445 final = &smack_known_star;
3446 /*
3447 * No break.
3448 *
3449 * If a smack value has been set we want to use it,
3450 * but since tmpfs isn't giving us the opportunity
3451 * to set mount options simulate setting the
3452 * superblock default.
3453 */
3454 default:
3455 /*
3456 * This isn't an understood special case.
3457 * Get the value from the xattr.
3458 */
3459
3460 /*
3461 * UNIX domain sockets use lower level socket data.
3462 */
3463 if (S_ISSOCK(inode->i_mode)) {
3464 final = &smack_known_star;
3465 break;
3466 }
3467 /*
3468 * No xattr support means, alas, no SMACK label.
3469 * Use the aforeapplied default.
3470 * It would be curious if the label of the task
3471 * does not match that assigned.
3472 */
3473 if (!(inode->i_opflags & IOP_XATTR))
3474 break;
3475 /*
3476 * Get the dentry for xattr.
3477 */
3478 dp = dget(opt_dentry);
3479 skp = smk_fetch(XATTR_NAME_SMACK, inode, dp);
3480 if (!IS_ERR_OR_NULL(skp))
3481 final = skp;
3482
3483 /*
3484 * Transmuting directory
3485 */
3486 if (S_ISDIR(inode->i_mode)) {
3487 /*
3488 * If this is a new directory and the label was
3489 * transmuted when the inode was initialized
3490 * set the transmute attribute on the directory
3491 * and mark the inode.
3492 *
3493 * If there is a transmute attribute on the
3494 * directory mark the inode.
3495 */
3496 if (isp->smk_flags & SMK_INODE_CHANGED) {
3497 isp->smk_flags &= ~SMK_INODE_CHANGED;
3498 rc = __vfs_setxattr(dp, inode,
3499 XATTR_NAME_SMACKTRANSMUTE,
3500 TRANS_TRUE, TRANS_TRUE_SIZE,
3501 0);
3502 } else {
3503 rc = __vfs_getxattr(dp, inode,
3504 XATTR_NAME_SMACKTRANSMUTE, trattr,
3505 TRANS_TRUE_SIZE);
3506 if (rc >= 0 && strncmp(trattr, TRANS_TRUE,
3507 TRANS_TRUE_SIZE) != 0)
3508 rc = -EINVAL;
3509 }
3510 if (rc >= 0)
3511 transflag = SMK_INODE_TRANSMUTE;
3512 }
3513 /*
3514 * Don't let the exec or mmap label be "*" or "@".
3515 */
3516 skp = smk_fetch(XATTR_NAME_SMACKEXEC, inode, dp);
3517 if (IS_ERR(skp) || skp == &smack_known_star ||
3518 skp == &smack_known_web)
3519 skp = NULL;
3520 isp->smk_task = skp;
3521
3522 skp = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp);
3523 if (IS_ERR(skp) || skp == &smack_known_star ||
3524 skp == &smack_known_web)
3525 skp = NULL;
3526 isp->smk_mmap = skp;
3527
3528 dput(dp);
3529 break;
3530 }
3531
3532 if (final == NULL)
3533 isp->smk_inode = ckp;
3534 else
3535 isp->smk_inode = final;
3536
3537 isp->smk_flags |= (SMK_INODE_INSTANT | transflag);
3538
3539unlockandout:
3540 mutex_unlock(&isp->smk_lock);
3541 return;
3542}
3543
3544/**
3545 * smack_getprocattr - Smack process attribute access
3546 * @p: the object task
3547 * @name: the name of the attribute in /proc/.../attr
3548 * @value: where to put the result
3549 *
3550 * Places a copy of the task Smack into value
3551 *
3552 * Returns the length of the smack label or an error code
3553 */
3554static int smack_getprocattr(struct task_struct *p, char *name, char **value)
3555{
3556 struct smack_known *skp = smk_of_task_struct(p);
3557 char *cp;
3558 int slen;
3559
3560 if (strcmp(name, "current") != 0)
3561 return -EINVAL;
3562
3563 cp = kstrdup(skp->smk_known, GFP_KERNEL);
3564 if (cp == NULL)
3565 return -ENOMEM;
3566
3567 slen = strlen(cp);
3568 *value = cp;
3569 return slen;
3570}
3571
3572/**
3573 * smack_setprocattr - Smack process attribute setting
3574 * @name: the name of the attribute in /proc/.../attr
3575 * @value: the value to set
3576 * @size: the size of the value
3577 *
3578 * Sets the Smack value of the task. Only setting self
3579 * is permitted and only with privilege
3580 *
3581 * Returns the length of the smack label or an error code
3582 */
3583static int smack_setprocattr(const char *name, void *value, size_t size)
3584{
3585 struct task_smack *tsp = current_security();
3586 struct cred *new;
3587 struct smack_known *skp;
3588 struct smack_known_list_elem *sklep;
3589 int rc;
3590
3591 if (!smack_privileged(CAP_MAC_ADMIN) && list_empty(&tsp->smk_relabel))
3592 return -EPERM;
3593
3594 if (value == NULL || size == 0 || size >= SMK_LONGLABEL)
3595 return -EINVAL;
3596
3597 if (strcmp(name, "current") != 0)
3598 return -EINVAL;
3599
3600 skp = smk_import_entry(value, size);
3601 if (IS_ERR(skp))
3602 return PTR_ERR(skp);
3603
3604 /*
3605 * No process is ever allowed the web ("@") label
3606 * and the star ("*") label.
3607 */
3608 if (skp == &smack_known_web || skp == &smack_known_star)
3609 return -EINVAL;
3610
3611 if (!smack_privileged(CAP_MAC_ADMIN)) {
3612 rc = -EPERM;
3613 list_for_each_entry(sklep, &tsp->smk_relabel, list)
3614 if (sklep->smk_label == skp) {
3615 rc = 0;
3616 break;
3617 }
3618 if (rc)
3619 return rc;
3620 }
3621
3622 new = prepare_creds();
3623 if (new == NULL)
3624 return -ENOMEM;
3625
3626 tsp = new->security;
3627 tsp->smk_task = skp;
3628 /*
3629 * process can change its label only once
3630 */
3631 smk_destroy_label_list(&tsp->smk_relabel);
3632
3633 commit_creds(new);
3634 return size;
3635}
3636
3637/**
3638 * smack_unix_stream_connect - Smack access on UDS
3639 * @sock: one sock
3640 * @other: the other sock
3641 * @newsk: unused
3642 *
3643 * Return 0 if a subject with the smack of sock could access
3644 * an object with the smack of other, otherwise an error code
3645 */
3646static int smack_unix_stream_connect(struct sock *sock,
3647 struct sock *other, struct sock *newsk)
3648{
3649 struct smack_known *skp;
3650 struct smack_known *okp;
3651 struct socket_smack *ssp = sock->sk_security;
3652 struct socket_smack *osp = other->sk_security;
3653 struct socket_smack *nsp = newsk->sk_security;
3654 struct smk_audit_info ad;
3655 int rc = 0;
3656#ifdef CONFIG_AUDIT
3657 struct lsm_network_audit net;
3658#endif
3659
3660 if (!smack_privileged(CAP_MAC_OVERRIDE)) {
3661 skp = ssp->smk_out;
3662 okp = osp->smk_in;
3663#ifdef CONFIG_AUDIT
3664 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
3665 smk_ad_setfield_u_net_sk(&ad, other);
3666#endif
3667 rc = smk_access(skp, okp, MAY_WRITE, &ad);
3668 rc = smk_bu_note("UDS connect", skp, okp, MAY_WRITE, rc);
3669 if (rc == 0) {
3670 okp = osp->smk_out;
3671 skp = ssp->smk_in;
3672 rc = smk_access(okp, skp, MAY_WRITE, &ad);
3673 rc = smk_bu_note("UDS connect", okp, skp,
3674 MAY_WRITE, rc);
3675 }
3676 }
3677
3678 /*
3679 * Cross reference the peer labels for SO_PEERSEC.
3680 */
3681 if (rc == 0) {
3682 nsp->smk_packet = ssp->smk_out;
3683 ssp->smk_packet = osp->smk_out;
3684 }
3685
3686 return rc;
3687}
3688
3689/**
3690 * smack_unix_may_send - Smack access on UDS
3691 * @sock: one socket
3692 * @other: the other socket
3693 *
3694 * Return 0 if a subject with the smack of sock could access
3695 * an object with the smack of other, otherwise an error code
3696 */
3697static int smack_unix_may_send(struct socket *sock, struct socket *other)
3698{
3699 struct socket_smack *ssp = sock->sk->sk_security;
3700 struct socket_smack *osp = other->sk->sk_security;
3701 struct smk_audit_info ad;
3702 int rc;
3703
3704#ifdef CONFIG_AUDIT
3705 struct lsm_network_audit net;
3706
3707 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
3708 smk_ad_setfield_u_net_sk(&ad, other->sk);
3709#endif
3710
3711 if (smack_privileged(CAP_MAC_OVERRIDE))
3712 return 0;
3713
3714 rc = smk_access(ssp->smk_out, osp->smk_in, MAY_WRITE, &ad);
3715 rc = smk_bu_note("UDS send", ssp->smk_out, osp->smk_in, MAY_WRITE, rc);
3716 return rc;
3717}
3718
3719/**
3720 * smack_socket_sendmsg - Smack check based on destination host
3721 * @sock: the socket
3722 * @msg: the message
3723 * @size: the size of the message
3724 *
3725 * Return 0 if the current subject can write to the destination host.
3726 * For IPv4 this is only a question if the destination is a single label host.
3727 * For IPv6 this is a check against the label of the port.
3728 */
3729static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3730 int size)
3731{
3732 struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name;
3733#if IS_ENABLED(CONFIG_IPV6)
3734 struct sockaddr_in6 *sap = (struct sockaddr_in6 *) msg->msg_name;
3735#endif
3736#ifdef SMACK_IPV6_SECMARK_LABELING
3737 struct socket_smack *ssp = sock->sk->sk_security;
3738 struct smack_known *rsp;
3739#endif
3740 int rc = 0;
3741
3742 /*
3743 * Perfectly reasonable for this to be NULL
3744 */
3745 if (sip == NULL)
3746 return 0;
3747
3748 switch (sock->sk->sk_family) {
3749 case AF_INET:
3750 rc = smack_netlabel_send(sock->sk, sip);
3751 break;
3752 case AF_INET6:
3753#ifdef SMACK_IPV6_SECMARK_LABELING
3754 rsp = smack_ipv6host_label(sap);
3755 if (rsp != NULL)
3756 rc = smk_ipv6_check(ssp->smk_out, rsp, sap,
3757 SMK_CONNECTING);
3758#endif
3759#ifdef SMACK_IPV6_PORT_LABELING
3760 rc = smk_ipv6_port_check(sock->sk, sap, SMK_SENDING);
3761#endif
3762 break;
3763 }
3764 return rc;
3765}
3766
3767/**
3768 * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat pair to smack
3769 * @sap: netlabel secattr
3770 * @ssp: socket security information
3771 *
3772 * Returns a pointer to a Smack label entry found on the label list.
3773 */
3774static struct smack_known *smack_from_secattr(struct netlbl_lsm_secattr *sap,
3775 struct socket_smack *ssp)
3776{
3777 struct smack_known *skp;
3778 int found = 0;
3779 int acat;
3780 int kcat;
3781
3782 if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) {
3783 /*
3784 * Looks like a CIPSO packet.
3785 * If there are flags but no level netlabel isn't
3786 * behaving the way we expect it to.
3787 *
3788 * Look it up in the label table
3789 * Without guidance regarding the smack value
3790 * for the packet fall back on the network
3791 * ambient value.
3792 */
3793 rcu_read_lock();
3794 list_for_each_entry_rcu(skp, &smack_known_list, list) {
3795 if (sap->attr.mls.lvl != skp->smk_netlabel.attr.mls.lvl)
3796 continue;
3797 /*
3798 * Compare the catsets. Use the netlbl APIs.
3799 */
3800 if ((sap->flags & NETLBL_SECATTR_MLS_CAT) == 0) {
3801 if ((skp->smk_netlabel.flags &
3802 NETLBL_SECATTR_MLS_CAT) == 0)
3803 found = 1;
3804 break;
3805 }
3806 for (acat = -1, kcat = -1; acat == kcat; ) {
3807 acat = netlbl_catmap_walk(sap->attr.mls.cat,
3808 acat + 1);
3809 kcat = netlbl_catmap_walk(
3810 skp->smk_netlabel.attr.mls.cat,
3811 kcat + 1);
3812 if (acat < 0 || kcat < 0)
3813 break;
3814 }
3815 if (acat == kcat) {
3816 found = 1;
3817 break;
3818 }
3819 }
3820 rcu_read_unlock();
3821
3822 if (found)
3823 return skp;
3824
3825 if (ssp != NULL && ssp->smk_in == &smack_known_star)
3826 return &smack_known_web;
3827 return &smack_known_star;
3828 }
3829 if ((sap->flags & NETLBL_SECATTR_SECID) != 0)
3830 /*
3831 * Looks like a fallback, which gives us a secid.
3832 */
3833 return smack_from_secid(sap->attr.secid);
3834 /*
3835 * Without guidance regarding the smack value
3836 * for the packet fall back on the network
3837 * ambient value.
3838 */
3839 return smack_net_ambient;
3840}
3841
3842#if IS_ENABLED(CONFIG_IPV6)
3843static int smk_skb_to_addr_ipv6(struct sk_buff *skb, struct sockaddr_in6 *sip)
3844{
3845 u8 nexthdr;
3846 int offset;
3847 int proto = -EINVAL;
3848 struct ipv6hdr _ipv6h;
3849 struct ipv6hdr *ip6;
3850 __be16 frag_off;
3851 struct tcphdr _tcph, *th;
3852 struct udphdr _udph, *uh;
3853 struct dccp_hdr _dccph, *dh;
3854
3855 sip->sin6_port = 0;
3856
3857 offset = skb_network_offset(skb);
3858 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3859 if (ip6 == NULL)
3860 return -EINVAL;
3861 sip->sin6_addr = ip6->saddr;
3862
3863 nexthdr = ip6->nexthdr;
3864 offset += sizeof(_ipv6h);
3865 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
3866 if (offset < 0)
3867 return -EINVAL;
3868
3869 proto = nexthdr;
3870 switch (proto) {
3871 case IPPROTO_TCP:
3872 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3873 if (th != NULL)
3874 sip->sin6_port = th->source;
3875 break;
3876 case IPPROTO_UDP:
3877 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3878 if (uh != NULL)
3879 sip->sin6_port = uh->source;
3880 break;
3881 case IPPROTO_DCCP:
3882 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3883 if (dh != NULL)
3884 sip->sin6_port = dh->dccph_sport;
3885 break;
3886 }
3887 return proto;
3888}
3889#endif /* CONFIG_IPV6 */
3890
3891/**
3892 * smack_socket_sock_rcv_skb - Smack packet delivery access check
3893 * @sk: socket
3894 * @skb: packet
3895 *
3896 * Returns 0 if the packet should be delivered, an error code otherwise
3897 */
3898static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
3899{
3900 struct netlbl_lsm_secattr secattr;
3901 struct socket_smack *ssp = sk->sk_security;
3902 struct smack_known *skp = NULL;
3903 int rc = 0;
3904 struct smk_audit_info ad;
3905#ifdef CONFIG_AUDIT
3906 struct lsm_network_audit net;
3907#endif
3908#if IS_ENABLED(CONFIG_IPV6)
3909 struct sockaddr_in6 sadd;
3910 int proto;
3911#endif /* CONFIG_IPV6 */
3912
3913 switch (sk->sk_family) {
3914 case PF_INET:
3915#ifdef CONFIG_SECURITY_SMACK_NETFILTER
3916 /*
3917 * If there is a secmark use it rather than the CIPSO label.
3918 * If there is no secmark fall back to CIPSO.
3919 * The secmark is assumed to reflect policy better.
3920 */
3921 if (skb && skb->secmark != 0) {
3922 skp = smack_from_secid(skb->secmark);
3923 goto access_check;
3924 }
3925#endif /* CONFIG_SECURITY_SMACK_NETFILTER */
3926 /*
3927 * Translate what netlabel gave us.
3928 */
3929 netlbl_secattr_init(&secattr);
3930
3931 rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr);
3932 if (rc == 0)
3933 skp = smack_from_secattr(&secattr, ssp);
3934 else
3935 skp = smack_net_ambient;
3936
3937 netlbl_secattr_destroy(&secattr);
3938
3939#ifdef CONFIG_SECURITY_SMACK_NETFILTER
3940access_check:
3941#endif
3942#ifdef CONFIG_AUDIT
3943 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
3944 ad.a.u.net->family = sk->sk_family;
3945 ad.a.u.net->netif = skb->skb_iif;
3946 ipv4_skb_to_auditdata(skb, &ad.a, NULL);
3947#endif
3948 /*
3949 * Receiving a packet requires that the other end
3950 * be able to write here. Read access is not required.
3951 * This is the simplist possible security model
3952 * for networking.
3953 */
3954 rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
3955 rc = smk_bu_note("IPv4 delivery", skp, ssp->smk_in,
3956 MAY_WRITE, rc);
3957 if (rc != 0)
3958 netlbl_skbuff_err(skb, sk->sk_family, rc, 0);
3959 break;
3960#if IS_ENABLED(CONFIG_IPV6)
3961 case PF_INET6:
3962 proto = smk_skb_to_addr_ipv6(skb, &sadd);
3963 if (proto != IPPROTO_UDP && proto != IPPROTO_TCP)
3964 break;
3965#ifdef SMACK_IPV6_SECMARK_LABELING
3966 if (skb && skb->secmark != 0)
3967 skp = smack_from_secid(skb->secmark);
3968 else
3969 skp = smack_ipv6host_label(&sadd);
3970 if (skp == NULL)
3971 skp = smack_net_ambient;
3972#ifdef CONFIG_AUDIT
3973 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
3974 ad.a.u.net->family = sk->sk_family;
3975 ad.a.u.net->netif = skb->skb_iif;
3976 ipv6_skb_to_auditdata(skb, &ad.a, NULL);
3977#endif /* CONFIG_AUDIT */
3978 rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
3979 rc = smk_bu_note("IPv6 delivery", skp, ssp->smk_in,
3980 MAY_WRITE, rc);
3981#endif /* SMACK_IPV6_SECMARK_LABELING */
3982#ifdef SMACK_IPV6_PORT_LABELING
3983 rc = smk_ipv6_port_check(sk, &sadd, SMK_RECEIVING);
3984#endif /* SMACK_IPV6_PORT_LABELING */
3985 break;
3986#endif /* CONFIG_IPV6 */
3987 }
3988
3989 return rc;
3990}
3991
3992/**
3993 * smack_socket_getpeersec_stream - pull in packet label
3994 * @sock: the socket
3995 * @optval: user's destination
3996 * @optlen: size thereof
3997 * @len: max thereof
3998 *
3999 * returns zero on success, an error code otherwise
4000 */
4001static int smack_socket_getpeersec_stream(struct socket *sock,
4002 char __user *optval,
4003 int __user *optlen, unsigned len)
4004{
4005 struct socket_smack *ssp;
4006 char *rcp = "";
4007 int slen = 1;
4008 int rc = 0;
4009
4010 ssp = sock->sk->sk_security;
4011 if (ssp->smk_packet != NULL) {
4012 rcp = ssp->smk_packet->smk_known;
4013 slen = strlen(rcp) + 1;
4014 }
4015
4016 if (slen > len)
4017 rc = -ERANGE;
4018 else if (copy_to_user(optval, rcp, slen) != 0)
4019 rc = -EFAULT;
4020
4021 if (put_user(slen, optlen) != 0)
4022 rc = -EFAULT;
4023
4024 return rc;
4025}
4026
4027
4028/**
4029 * smack_socket_getpeersec_dgram - pull in packet label
4030 * @sock: the peer socket
4031 * @skb: packet data
4032 * @secid: pointer to where to put the secid of the packet
4033 *
4034 * Sets the netlabel socket state on sk from parent
4035 */
4036static int smack_socket_getpeersec_dgram(struct socket *sock,
4037 struct sk_buff *skb, u32 *secid)
4038
4039{
4040 struct netlbl_lsm_secattr secattr;
4041 struct socket_smack *ssp = NULL;
4042 struct smack_known *skp;
4043 int family = PF_UNSPEC;
4044 u32 s = 0; /* 0 is the invalid secid */
4045 int rc;
4046
4047 if (skb != NULL) {
4048 if (skb->protocol == htons(ETH_P_IP))
4049 family = PF_INET;
4050#if IS_ENABLED(CONFIG_IPV6)
4051 else if (skb->protocol == htons(ETH_P_IPV6))
4052 family = PF_INET6;
4053#endif /* CONFIG_IPV6 */
4054 }
4055 if (family == PF_UNSPEC && sock != NULL)
4056 family = sock->sk->sk_family;
4057
4058 switch (family) {
4059 case PF_UNIX:
4060 ssp = sock->sk->sk_security;
4061 s = ssp->smk_out->smk_secid;
4062 break;
4063 case PF_INET:
4064#ifdef CONFIG_SECURITY_SMACK_NETFILTER
4065 s = skb->secmark;
4066 if (s != 0)
4067 break;
4068#endif
4069 /*
4070 * Translate what netlabel gave us.
4071 */
4072 if (sock != NULL && sock->sk != NULL)
4073 ssp = sock->sk->sk_security;
4074 netlbl_secattr_init(&secattr);
4075 rc = netlbl_skbuff_getattr(skb, family, &secattr);
4076 if (rc == 0) {
4077 skp = smack_from_secattr(&secattr, ssp);
4078 s = skp->smk_secid;
4079 }
4080 netlbl_secattr_destroy(&secattr);
4081 break;
4082 case PF_INET6:
4083#ifdef SMACK_IPV6_SECMARK_LABELING
4084 s = skb->secmark;
4085#endif
4086 break;
4087 }
4088 *secid = s;
4089 if (s == 0)
4090 return -EINVAL;
4091 return 0;
4092}
4093
4094/**
4095 * smack_sock_graft - Initialize a newly created socket with an existing sock
4096 * @sk: child sock
4097 * @parent: parent socket
4098 *
4099 * Set the smk_{in,out} state of an existing sock based on the process that
4100 * is creating the new socket.
4101 */
4102static void smack_sock_graft(struct sock *sk, struct socket *parent)
4103{
4104 struct socket_smack *ssp;
4105 struct smack_known *skp = smk_of_current();
4106
4107 if (sk == NULL ||
4108 (sk->sk_family != PF_INET && sk->sk_family != PF_INET6))
4109 return;
4110
4111 ssp = sk->sk_security;
4112 ssp->smk_in = skp;
4113 ssp->smk_out = skp;
4114 /* cssp->smk_packet is already set in smack_inet_csk_clone() */
4115}
4116
4117/**
4118 * smack_inet_conn_request - Smack access check on connect
4119 * @sk: socket involved
4120 * @skb: packet
4121 * @req: unused
4122 *
4123 * Returns 0 if a task with the packet label could write to
4124 * the socket, otherwise an error code
4125 */
4126static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4127 struct request_sock *req)
4128{
4129 u16 family = sk->sk_family;
4130 struct smack_known *skp;
4131 struct socket_smack *ssp = sk->sk_security;
4132 struct netlbl_lsm_secattr secattr;
4133 struct sockaddr_in addr;
4134 struct iphdr *hdr;
4135 struct smack_known *hskp;
4136 int rc;
4137 struct smk_audit_info ad;
4138#ifdef CONFIG_AUDIT
4139 struct lsm_network_audit net;
4140#endif
4141
4142#if IS_ENABLED(CONFIG_IPV6)
4143 if (family == PF_INET6) {
4144 /*
4145 * Handle mapped IPv4 packets arriving
4146 * via IPv6 sockets. Don't set up netlabel
4147 * processing on IPv6.
4148 */
4149 if (skb->protocol == htons(ETH_P_IP))
4150 family = PF_INET;
4151 else
4152 return 0;
4153 }
4154#endif /* CONFIG_IPV6 */
4155
4156#ifdef CONFIG_SECURITY_SMACK_NETFILTER
4157 /*
4158 * If there is a secmark use it rather than the CIPSO label.
4159 * If there is no secmark fall back to CIPSO.
4160 * The secmark is assumed to reflect policy better.
4161 */
4162 if (skb && skb->secmark != 0) {
4163 skp = smack_from_secid(skb->secmark);
4164 goto access_check;
4165 }
4166#endif /* CONFIG_SECURITY_SMACK_NETFILTER */
4167
4168 netlbl_secattr_init(&secattr);
4169 rc = netlbl_skbuff_getattr(skb, family, &secattr);
4170 if (rc == 0)
4171 skp = smack_from_secattr(&secattr, ssp);
4172 else
4173 skp = &smack_known_huh;
4174 netlbl_secattr_destroy(&secattr);
4175
4176#ifdef CONFIG_SECURITY_SMACK_NETFILTER
4177access_check:
4178#endif
4179
4180#ifdef CONFIG_AUDIT
4181 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
4182 ad.a.u.net->family = family;
4183 ad.a.u.net->netif = skb->skb_iif;
4184 ipv4_skb_to_auditdata(skb, &ad.a, NULL);
4185#endif
4186 /*
4187 * Receiving a packet requires that the other end be able to write
4188 * here. Read access is not required.
4189 */
4190 rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
4191 rc = smk_bu_note("IPv4 connect", skp, ssp->smk_in, MAY_WRITE, rc);
4192 if (rc != 0)
4193 return rc;
4194
4195 /*
4196 * Save the peer's label in the request_sock so we can later setup
4197 * smk_packet in the child socket so that SO_PEERCRED can report it.
4198 */
4199 req->peer_secid = skp->smk_secid;
4200
4201 /*
4202 * We need to decide if we want to label the incoming connection here
4203 * if we do we only need to label the request_sock and the stack will
4204 * propagate the wire-label to the sock when it is created.
4205 */
4206 hdr = ip_hdr(skb);
4207 addr.sin_addr.s_addr = hdr->saddr;
4208 rcu_read_lock();
4209 hskp = smack_ipv4host_label(&addr);
4210 rcu_read_unlock();
4211
4212 if (hskp == NULL)
4213 rc = netlbl_req_setattr(req, &skp->smk_netlabel);
4214 else
4215 netlbl_req_delattr(req);
4216
4217 return rc;
4218}
4219
4220/**
4221 * smack_inet_csk_clone - Copy the connection information to the new socket
4222 * @sk: the new socket
4223 * @req: the connection's request_sock
4224 *
4225 * Transfer the connection's peer label to the newly created socket.
4226 */
4227static void smack_inet_csk_clone(struct sock *sk,
4228 const struct request_sock *req)
4229{
4230 struct socket_smack *ssp = sk->sk_security;
4231 struct smack_known *skp;
4232
4233 if (req->peer_secid != 0) {
4234 skp = smack_from_secid(req->peer_secid);
4235 ssp->smk_packet = skp;
4236 } else
4237 ssp->smk_packet = NULL;
4238}
4239
4240/*
4241 * Key management security hooks
4242 *
4243 * Casey has not tested key support very heavily.
4244 * The permission check is most likely too restrictive.
4245 * If you care about keys please have a look.
4246 */
4247#ifdef CONFIG_KEYS
4248
4249/**
4250 * smack_key_alloc - Set the key security blob
4251 * @key: object
4252 * @cred: the credentials to use
4253 * @flags: unused
4254 *
4255 * No allocation required
4256 *
4257 * Returns 0
4258 */
4259static int smack_key_alloc(struct key *key, const struct cred *cred,
4260 unsigned long flags)
4261{
4262 struct smack_known *skp = smk_of_task(cred->security);
4263
4264 key->security = skp;
4265 return 0;
4266}
4267
4268/**
4269 * smack_key_free - Clear the key security blob
4270 * @key: the object
4271 *
4272 * Clear the blob pointer
4273 */
4274static void smack_key_free(struct key *key)
4275{
4276 key->security = NULL;
4277}
4278
4279/**
4280 * smack_key_permission - Smack access on a key
4281 * @key_ref: gets to the object
4282 * @cred: the credentials to use
4283 * @perm: requested key permissions
4284 *
4285 * Return 0 if the task has read and write to the object,
4286 * an error code otherwise
4287 */
4288static int smack_key_permission(key_ref_t key_ref,
4289 const struct cred *cred, unsigned perm)
4290{
4291 struct key *keyp;
4292 struct smk_audit_info ad;
4293 struct smack_known *tkp = smk_of_task(cred->security);
4294 int request = 0;
4295 int rc;
4296
4297 keyp = key_ref_to_ptr(key_ref);
4298 if (keyp == NULL)
4299 return -EINVAL;
4300 /*
4301 * If the key hasn't been initialized give it access so that
4302 * it may do so.
4303 */
4304 if (keyp->security == NULL)
4305 return 0;
4306 /*
4307 * This should not occur
4308 */
4309 if (tkp == NULL)
4310 return -EACCES;
4311
4312 if (smack_privileged_cred(CAP_MAC_OVERRIDE, cred))
4313 return 0;
4314
4315#ifdef CONFIG_AUDIT
4316 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY);
4317 ad.a.u.key_struct.key = keyp->serial;
4318 ad.a.u.key_struct.key_desc = keyp->description;
4319#endif
4320 if (perm & KEY_NEED_READ)
4321 request = MAY_READ;
4322 if (perm & (KEY_NEED_WRITE | KEY_NEED_LINK | KEY_NEED_SETATTR))
4323 request = MAY_WRITE;
4324 rc = smk_access(tkp, keyp->security, request, &ad);
4325 rc = smk_bu_note("key access", tkp, keyp->security, request, rc);
4326 return rc;
4327}
4328
4329/*
4330 * smack_key_getsecurity - Smack label tagging the key
4331 * @key points to the key to be queried
4332 * @_buffer points to a pointer that should be set to point to the
4333 * resulting string (if no label or an error occurs).
4334 * Return the length of the string (including terminating NUL) or -ve if
4335 * an error.
4336 * May also return 0 (and a NULL buffer pointer) if there is no label.
4337 */
4338static int smack_key_getsecurity(struct key *key, char **_buffer)
4339{
4340 struct smack_known *skp = key->security;
4341 size_t length;
4342 char *copy;
4343
4344 if (key->security == NULL) {
4345 *_buffer = NULL;
4346 return 0;
4347 }
4348
4349 copy = kstrdup(skp->smk_known, GFP_KERNEL);
4350 if (copy == NULL)
4351 return -ENOMEM;
4352 length = strlen(copy) + 1;
4353
4354 *_buffer = copy;
4355 return length;
4356}
4357
4358#endif /* CONFIG_KEYS */
4359
4360/*
4361 * Smack Audit hooks
4362 *
4363 * Audit requires a unique representation of each Smack specific
4364 * rule. This unique representation is used to distinguish the
4365 * object to be audited from remaining kernel objects and also
4366 * works as a glue between the audit hooks.
4367 *
4368 * Since repository entries are added but never deleted, we'll use
4369 * the smack_known label address related to the given audit rule as
4370 * the needed unique representation. This also better fits the smack
4371 * model where nearly everything is a label.
4372 */
4373#ifdef CONFIG_AUDIT
4374
4375/**
4376 * smack_audit_rule_init - Initialize a smack audit rule
4377 * @field: audit rule fields given from user-space (audit.h)
4378 * @op: required testing operator (=, !=, >, <, ...)
4379 * @rulestr: smack label to be audited
4380 * @vrule: pointer to save our own audit rule representation
4381 *
4382 * Prepare to audit cases where (@field @op @rulestr) is true.
4383 * The label to be audited is created if necessay.
4384 */
4385static int smack_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
4386{
4387 struct smack_known *skp;
4388 char **rule = (char **)vrule;
4389 *rule = NULL;
4390
4391 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
4392 return -EINVAL;
4393
4394 if (op != Audit_equal && op != Audit_not_equal)
4395 return -EINVAL;
4396
4397 skp = smk_import_entry(rulestr, 0);
4398 if (IS_ERR(skp))
4399 return PTR_ERR(skp);
4400
4401 *rule = skp->smk_known;
4402
4403 return 0;
4404}
4405
4406/**
4407 * smack_audit_rule_known - Distinguish Smack audit rules
4408 * @krule: rule of interest, in Audit kernel representation format
4409 *
4410 * This is used to filter Smack rules from remaining Audit ones.
4411 * If it's proved that this rule belongs to us, the
4412 * audit_rule_match hook will be called to do the final judgement.
4413 */
4414static int smack_audit_rule_known(struct audit_krule *krule)
4415{
4416 struct audit_field *f;
4417 int i;
4418
4419 for (i = 0; i < krule->field_count; i++) {
4420 f = &krule->fields[i];
4421
4422 if (f->type == AUDIT_SUBJ_USER || f->type == AUDIT_OBJ_USER)
4423 return 1;
4424 }
4425
4426 return 0;
4427}
4428
4429/**
4430 * smack_audit_rule_match - Audit given object ?
4431 * @secid: security id for identifying the object to test
4432 * @field: audit rule flags given from user-space
4433 * @op: required testing operator
4434 * @vrule: smack internal rule presentation
4435 * @actx: audit context associated with the check
4436 *
4437 * The core Audit hook. It's used to take the decision of
4438 * whether to audit or not to audit a given object.
4439 */
4440static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule,
4441 struct audit_context *actx)
4442{
4443 struct smack_known *skp;
4444 char *rule = vrule;
4445
4446 if (unlikely(!rule)) {
4447 WARN_ONCE(1, "Smack: missing rule\n");
4448 return -ENOENT;
4449 }
4450
4451 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
4452 return 0;
4453
4454 skp = smack_from_secid(secid);
4455
4456 /*
4457 * No need to do string comparisons. If a match occurs,
4458 * both pointers will point to the same smack_known
4459 * label.
4460 */
4461 if (op == Audit_equal)
4462 return (rule == skp->smk_known);
4463 if (op == Audit_not_equal)
4464 return (rule != skp->smk_known);
4465
4466 return 0;
4467}
4468
4469/*
4470 * There is no need for a smack_audit_rule_free hook.
4471 * No memory was allocated.
4472 */
4473
4474#endif /* CONFIG_AUDIT */
4475
4476/**
4477 * smack_ismaclabel - check if xattr @name references a smack MAC label
4478 * @name: Full xattr name to check.
4479 */
4480static int smack_ismaclabel(const char *name)
4481{
4482 return (strcmp(name, XATTR_SMACK_SUFFIX) == 0);
4483}
4484
4485
4486/**
4487 * smack_secid_to_secctx - return the smack label for a secid
4488 * @secid: incoming integer
4489 * @secdata: destination
4490 * @seclen: how long it is
4491 *
4492 * Exists for networking code.
4493 */
4494static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
4495{
4496 struct smack_known *skp = smack_from_secid(secid);
4497
4498 if (secdata)
4499 *secdata = skp->smk_known;
4500 *seclen = strlen(skp->smk_known);
4501 return 0;
4502}
4503
4504/**
4505 * smack_secctx_to_secid - return the secid for a smack label
4506 * @secdata: smack label
4507 * @seclen: how long result is
4508 * @secid: outgoing integer
4509 *
4510 * Exists for audit and networking code.
4511 */
4512static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
4513{
4514 struct smack_known *skp = smk_find_entry(secdata);
4515
4516 if (skp)
4517 *secid = skp->smk_secid;
4518 else
4519 *secid = 0;
4520 return 0;
4521}
4522
4523/*
4524 * There used to be a smack_release_secctx hook
4525 * that did nothing back when hooks were in a vector.
4526 * Now that there's a list such a hook adds cost.
4527 */
4528
4529static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
4530{
4531 return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx, ctxlen, 0);
4532}
4533
4534static int smack_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
4535{
4536 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SMACK, ctx, ctxlen, 0);
4537}
4538
4539static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
4540{
4541 int len = 0;
4542 len = smack_inode_getsecurity(inode, XATTR_SMACK_SUFFIX, ctx, true);
4543
4544 if (len < 0)
4545 return len;
4546 *ctxlen = len;
4547 return 0;
4548}
4549
4550static int smack_inode_copy_up(struct dentry *dentry, struct cred **new)
4551{
4552
4553 struct task_smack *tsp;
4554 struct smack_known *skp;
4555 struct inode_smack *isp;
4556 struct cred *new_creds = *new;
4557
4558 if (new_creds == NULL) {
4559 new_creds = prepare_creds();
4560 if (new_creds == NULL)
4561 return -ENOMEM;
4562 }
4563
4564 tsp = new_creds->security;
4565
4566 /*
4567 * Get label from overlay inode and set it in create_sid
4568 */
4569 isp = d_inode(dentry->d_parent)->i_security;
4570 skp = isp->smk_inode;
4571 tsp->smk_task = skp;
4572 *new = new_creds;
4573 return 0;
4574}
4575
4576static int smack_inode_copy_up_xattr(const char *name)
4577{
4578 /*
4579 * Return 1 if this is the smack access Smack attribute.
4580 */
4581 if (strcmp(name, XATTR_NAME_SMACK) == 0)
4582 return 1;
4583
4584 return -EOPNOTSUPP;
4585}
4586
4587static int smack_dentry_create_files_as(struct dentry *dentry, int mode,
4588 struct qstr *name,
4589 const struct cred *old,
4590 struct cred *new)
4591{
4592 struct task_smack *otsp = old->security;
4593 struct task_smack *ntsp = new->security;
4594 struct inode_smack *isp;
4595 int may;
4596
4597 /*
4598 * Use the process credential unless all of
4599 * the transmuting criteria are met
4600 */
4601 ntsp->smk_task = otsp->smk_task;
4602
4603 /*
4604 * the attribute of the containing directory
4605 */
4606 isp = d_inode(dentry->d_parent)->i_security;
4607
4608 if (isp->smk_flags & SMK_INODE_TRANSMUTE) {
4609 rcu_read_lock();
4610 may = smk_access_entry(otsp->smk_task->smk_known,
4611 isp->smk_inode->smk_known,
4612 &otsp->smk_task->smk_rules);
4613 rcu_read_unlock();
4614
4615 /*
4616 * If the directory is transmuting and the rule
4617 * providing access is transmuting use the containing
4618 * directory label instead of the process label.
4619 */
4620 if (may > 0 && (may & MAY_TRANSMUTE))
4621 ntsp->smk_task = isp->smk_inode;
4622 }
4623 return 0;
4624}
4625
4626static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
4627 LSM_HOOK_INIT(ptrace_access_check, smack_ptrace_access_check),
4628 LSM_HOOK_INIT(ptrace_traceme, smack_ptrace_traceme),
4629 LSM_HOOK_INIT(syslog, smack_syslog),
4630
4631 LSM_HOOK_INIT(sb_alloc_security, smack_sb_alloc_security),
4632 LSM_HOOK_INIT(sb_free_security, smack_sb_free_security),
4633 LSM_HOOK_INIT(sb_copy_data, smack_sb_copy_data),
4634 LSM_HOOK_INIT(sb_kern_mount, smack_sb_kern_mount),
4635 LSM_HOOK_INIT(sb_statfs, smack_sb_statfs),
4636 LSM_HOOK_INIT(sb_set_mnt_opts, smack_set_mnt_opts),
4637 LSM_HOOK_INIT(sb_parse_opts_str, smack_parse_opts_str),
4638
4639 LSM_HOOK_INIT(bprm_set_creds, smack_bprm_set_creds),
4640
4641 LSM_HOOK_INIT(inode_alloc_security, smack_inode_alloc_security),
4642 LSM_HOOK_INIT(inode_free_security, smack_inode_free_security),
4643 LSM_HOOK_INIT(inode_init_security, smack_inode_init_security),
4644 LSM_HOOK_INIT(inode_link, smack_inode_link),
4645 LSM_HOOK_INIT(inode_unlink, smack_inode_unlink),
4646 LSM_HOOK_INIT(inode_rmdir, smack_inode_rmdir),
4647 LSM_HOOK_INIT(inode_rename, smack_inode_rename),
4648 LSM_HOOK_INIT(inode_permission, smack_inode_permission),
4649 LSM_HOOK_INIT(inode_setattr, smack_inode_setattr),
4650 LSM_HOOK_INIT(inode_getattr, smack_inode_getattr),
4651 LSM_HOOK_INIT(inode_setxattr, smack_inode_setxattr),
4652 LSM_HOOK_INIT(inode_post_setxattr, smack_inode_post_setxattr),
4653 LSM_HOOK_INIT(inode_getxattr, smack_inode_getxattr),
4654 LSM_HOOK_INIT(inode_removexattr, smack_inode_removexattr),
4655 LSM_HOOK_INIT(inode_getsecurity, smack_inode_getsecurity),
4656 LSM_HOOK_INIT(inode_setsecurity, smack_inode_setsecurity),
4657 LSM_HOOK_INIT(inode_listsecurity, smack_inode_listsecurity),
4658 LSM_HOOK_INIT(inode_getsecid, smack_inode_getsecid),
4659
4660 LSM_HOOK_INIT(file_alloc_security, smack_file_alloc_security),
4661 LSM_HOOK_INIT(file_free_security, smack_file_free_security),
4662 LSM_HOOK_INIT(file_ioctl, smack_file_ioctl),
4663 LSM_HOOK_INIT(file_lock, smack_file_lock),
4664 LSM_HOOK_INIT(file_fcntl, smack_file_fcntl),
4665 LSM_HOOK_INIT(mmap_file, smack_mmap_file),
4666 LSM_HOOK_INIT(mmap_addr, cap_mmap_addr),
4667 LSM_HOOK_INIT(file_set_fowner, smack_file_set_fowner),
4668 LSM_HOOK_INIT(file_send_sigiotask, smack_file_send_sigiotask),
4669 LSM_HOOK_INIT(file_receive, smack_file_receive),
4670
4671 LSM_HOOK_INIT(file_open, smack_file_open),
4672
4673 LSM_HOOK_INIT(cred_alloc_blank, smack_cred_alloc_blank),
4674 LSM_HOOK_INIT(cred_free, smack_cred_free),
4675 LSM_HOOK_INIT(cred_prepare, smack_cred_prepare),
4676 LSM_HOOK_INIT(cred_transfer, smack_cred_transfer),
4677 LSM_HOOK_INIT(cred_getsecid, smack_cred_getsecid),
4678 LSM_HOOK_INIT(kernel_act_as, smack_kernel_act_as),
4679 LSM_HOOK_INIT(kernel_create_files_as, smack_kernel_create_files_as),
4680 LSM_HOOK_INIT(task_setpgid, smack_task_setpgid),
4681 LSM_HOOK_INIT(task_getpgid, smack_task_getpgid),
4682 LSM_HOOK_INIT(task_getsid, smack_task_getsid),
4683 LSM_HOOK_INIT(task_getsecid, smack_task_getsecid),
4684 LSM_HOOK_INIT(task_setnice, smack_task_setnice),
4685 LSM_HOOK_INIT(task_setioprio, smack_task_setioprio),
4686 LSM_HOOK_INIT(task_getioprio, smack_task_getioprio),
4687 LSM_HOOK_INIT(task_setscheduler, smack_task_setscheduler),
4688 LSM_HOOK_INIT(task_getscheduler, smack_task_getscheduler),
4689 LSM_HOOK_INIT(task_movememory, smack_task_movememory),
4690 LSM_HOOK_INIT(task_kill, smack_task_kill),
4691 LSM_HOOK_INIT(task_to_inode, smack_task_to_inode),
4692
4693 LSM_HOOK_INIT(ipc_permission, smack_ipc_permission),
4694 LSM_HOOK_INIT(ipc_getsecid, smack_ipc_getsecid),
4695
4696 LSM_HOOK_INIT(msg_msg_alloc_security, smack_msg_msg_alloc_security),
4697 LSM_HOOK_INIT(msg_msg_free_security, smack_msg_msg_free_security),
4698
4699 LSM_HOOK_INIT(msg_queue_alloc_security, smack_ipc_alloc_security),
4700 LSM_HOOK_INIT(msg_queue_free_security, smack_ipc_free_security),
4701 LSM_HOOK_INIT(msg_queue_associate, smack_msg_queue_associate),
4702 LSM_HOOK_INIT(msg_queue_msgctl, smack_msg_queue_msgctl),
4703 LSM_HOOK_INIT(msg_queue_msgsnd, smack_msg_queue_msgsnd),
4704 LSM_HOOK_INIT(msg_queue_msgrcv, smack_msg_queue_msgrcv),
4705
4706 LSM_HOOK_INIT(shm_alloc_security, smack_ipc_alloc_security),
4707 LSM_HOOK_INIT(shm_free_security, smack_ipc_free_security),
4708 LSM_HOOK_INIT(shm_associate, smack_shm_associate),
4709 LSM_HOOK_INIT(shm_shmctl, smack_shm_shmctl),
4710 LSM_HOOK_INIT(shm_shmat, smack_shm_shmat),
4711
4712 LSM_HOOK_INIT(sem_alloc_security, smack_ipc_alloc_security),
4713 LSM_HOOK_INIT(sem_free_security, smack_ipc_free_security),
4714 LSM_HOOK_INIT(sem_associate, smack_sem_associate),
4715 LSM_HOOK_INIT(sem_semctl, smack_sem_semctl),
4716 LSM_HOOK_INIT(sem_semop, smack_sem_semop),
4717
4718 LSM_HOOK_INIT(d_instantiate, smack_d_instantiate),
4719
4720 LSM_HOOK_INIT(getprocattr, smack_getprocattr),
4721 LSM_HOOK_INIT(setprocattr, smack_setprocattr),
4722
4723 LSM_HOOK_INIT(unix_stream_connect, smack_unix_stream_connect),
4724 LSM_HOOK_INIT(unix_may_send, smack_unix_may_send),
4725
4726 LSM_HOOK_INIT(socket_post_create, smack_socket_post_create),
4727#ifdef SMACK_IPV6_PORT_LABELING
4728 LSM_HOOK_INIT(socket_bind, smack_socket_bind),
4729#endif
4730 LSM_HOOK_INIT(socket_connect, smack_socket_connect),
4731 LSM_HOOK_INIT(socket_sendmsg, smack_socket_sendmsg),
4732 LSM_HOOK_INIT(socket_sock_rcv_skb, smack_socket_sock_rcv_skb),
4733 LSM_HOOK_INIT(socket_getpeersec_stream, smack_socket_getpeersec_stream),
4734 LSM_HOOK_INIT(socket_getpeersec_dgram, smack_socket_getpeersec_dgram),
4735 LSM_HOOK_INIT(sk_alloc_security, smack_sk_alloc_security),
4736 LSM_HOOK_INIT(sk_free_security, smack_sk_free_security),
4737 LSM_HOOK_INIT(sock_graft, smack_sock_graft),
4738 LSM_HOOK_INIT(inet_conn_request, smack_inet_conn_request),
4739 LSM_HOOK_INIT(inet_csk_clone, smack_inet_csk_clone),
4740
4741 /* key management security hooks */
4742#ifdef CONFIG_KEYS
4743 LSM_HOOK_INIT(key_alloc, smack_key_alloc),
4744 LSM_HOOK_INIT(key_free, smack_key_free),
4745 LSM_HOOK_INIT(key_permission, smack_key_permission),
4746 LSM_HOOK_INIT(key_getsecurity, smack_key_getsecurity),
4747#endif /* CONFIG_KEYS */
4748
4749 /* Audit hooks */
4750#ifdef CONFIG_AUDIT
4751 LSM_HOOK_INIT(audit_rule_init, smack_audit_rule_init),
4752 LSM_HOOK_INIT(audit_rule_known, smack_audit_rule_known),
4753 LSM_HOOK_INIT(audit_rule_match, smack_audit_rule_match),
4754#endif /* CONFIG_AUDIT */
4755
4756 LSM_HOOK_INIT(ismaclabel, smack_ismaclabel),
4757 LSM_HOOK_INIT(secid_to_secctx, smack_secid_to_secctx),
4758 LSM_HOOK_INIT(secctx_to_secid, smack_secctx_to_secid),
4759 LSM_HOOK_INIT(inode_notifysecctx, smack_inode_notifysecctx),
4760 LSM_HOOK_INIT(inode_setsecctx, smack_inode_setsecctx),
4761 LSM_HOOK_INIT(inode_getsecctx, smack_inode_getsecctx),
4762 LSM_HOOK_INIT(inode_copy_up, smack_inode_copy_up),
4763 LSM_HOOK_INIT(inode_copy_up_xattr, smack_inode_copy_up_xattr),
4764 LSM_HOOK_INIT(dentry_create_files_as, smack_dentry_create_files_as),
4765};
4766
4767
4768static __init void init_smack_known_list(void)
4769{
4770 /*
4771 * Initialize rule list locks
4772 */
4773 mutex_init(&smack_known_huh.smk_rules_lock);
4774 mutex_init(&smack_known_hat.smk_rules_lock);
4775 mutex_init(&smack_known_floor.smk_rules_lock);
4776 mutex_init(&smack_known_star.smk_rules_lock);
4777 mutex_init(&smack_known_web.smk_rules_lock);
4778 /*
4779 * Initialize rule lists
4780 */
4781 INIT_LIST_HEAD(&smack_known_huh.smk_rules);
4782 INIT_LIST_HEAD(&smack_known_hat.smk_rules);
4783 INIT_LIST_HEAD(&smack_known_star.smk_rules);
4784 INIT_LIST_HEAD(&smack_known_floor.smk_rules);
4785 INIT_LIST_HEAD(&smack_known_web.smk_rules);
4786 /*
4787 * Create the known labels list
4788 */
4789 smk_insert_entry(&smack_known_huh);
4790 smk_insert_entry(&smack_known_hat);
4791 smk_insert_entry(&smack_known_star);
4792 smk_insert_entry(&smack_known_floor);
4793 smk_insert_entry(&smack_known_web);
4794}
4795
4796/**
4797 * smack_init - initialize the smack system
4798 *
4799 * Returns 0
4800 */
4801static __init int smack_init(void)
4802{
4803 struct cred *cred;
4804 struct task_smack *tsp;
4805
4806 if (!security_module_enable("smack"))
4807 return 0;
4808
4809 smack_inode_cache = KMEM_CACHE(inode_smack, 0);
4810 if (!smack_inode_cache)
4811 return -ENOMEM;
4812
4813 tsp = new_task_smack(&smack_known_floor, &smack_known_floor,
4814 GFP_KERNEL);
4815 if (tsp == NULL) {
4816 kmem_cache_destroy(smack_inode_cache);
4817 return -ENOMEM;
4818 }
4819
4820 smack_enabled = 1;
4821
4822 pr_info("Smack: Initializing.\n");
4823#ifdef CONFIG_SECURITY_SMACK_NETFILTER
4824 pr_info("Smack: Netfilter enabled.\n");
4825#endif
4826#ifdef SMACK_IPV6_PORT_LABELING
4827 pr_info("Smack: IPv6 port labeling enabled.\n");
4828#endif
4829#ifdef SMACK_IPV6_SECMARK_LABELING
4830 pr_info("Smack: IPv6 Netfilter enabled.\n");
4831#endif
4832
4833 /*
4834 * Set the security state for the initial task.
4835 */
4836 cred = (struct cred *) current->cred;
4837 cred->security = tsp;
4838
4839 /* initialize the smack_known_list */
4840 init_smack_known_list();
4841
4842 /*
4843 * Register with LSM
4844 */
4845 security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks), "smack");
4846
4847 return 0;
4848}
4849
4850/*
4851 * Smack requires early initialization in order to label
4852 * all processes and objects when they are created.
4853 */
4854security_initcall(smack_init);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Simplified MAC Kernel (smack) security module
4 *
5 * This file contains the smack hook function implementations.
6 *
7 * Authors:
8 * Casey Schaufler <casey@schaufler-ca.com>
9 * Jarkko Sakkinen <jarkko.sakkinen@intel.com>
10 *
11 * Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com>
12 * Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
13 * Paul Moore <paul@paul-moore.com>
14 * Copyright (C) 2010 Nokia Corporation
15 * Copyright (C) 2011 Intel Corporation.
16 */
17
18#include <linux/xattr.h>
19#include <linux/pagemap.h>
20#include <linux/mount.h>
21#include <linux/stat.h>
22#include <linux/kd.h>
23#include <asm/ioctls.h>
24#include <linux/ip.h>
25#include <linux/tcp.h>
26#include <linux/udp.h>
27#include <linux/dccp.h>
28#include <linux/icmpv6.h>
29#include <linux/slab.h>
30#include <linux/mutex.h>
31#include <net/cipso_ipv4.h>
32#include <net/ip.h>
33#include <net/ipv6.h>
34#include <linux/audit.h>
35#include <linux/magic.h>
36#include <linux/dcache.h>
37#include <linux/personality.h>
38#include <linux/msg.h>
39#include <linux/shm.h>
40#include <uapi/linux/shm.h>
41#include <linux/binfmts.h>
42#include <linux/parser.h>
43#include <linux/fs_context.h>
44#include <linux/fs_parser.h>
45#include <linux/watch_queue.h>
46#include <linux/io_uring/cmd.h>
47#include <uapi/linux/lsm.h>
48#include "smack.h"
49
50#define TRANS_TRUE "TRUE"
51#define TRANS_TRUE_SIZE 4
52
53#define SMK_CONNECTING 0
54#define SMK_RECEIVING 1
55#define SMK_SENDING 2
56
57/*
58 * Smack uses multiple xattrs.
59 * SMACK64 - for access control,
60 * SMACK64TRANSMUTE - label initialization,
61 * Not saved on files - SMACK64IPIN and SMACK64IPOUT,
62 * Must be set explicitly - SMACK64EXEC and SMACK64MMAP
63 */
64#define SMACK_INODE_INIT_XATTRS 2
65
66#ifdef SMACK_IPV6_PORT_LABELING
67static DEFINE_MUTEX(smack_ipv6_lock);
68static LIST_HEAD(smk_ipv6_port_list);
69#endif
70struct kmem_cache *smack_rule_cache;
71int smack_enabled __initdata;
72
73#define A(s) {"smack"#s, sizeof("smack"#s) - 1, Opt_##s}
74static struct {
75 const char *name;
76 int len;
77 int opt;
78} smk_mount_opts[] = {
79 {"smackfsdef", sizeof("smackfsdef") - 1, Opt_fsdefault},
80 A(fsdefault), A(fsfloor), A(fshat), A(fsroot), A(fstransmute)
81};
82#undef A
83
84static int match_opt_prefix(char *s, int l, char **arg)
85{
86 int i;
87
88 for (i = 0; i < ARRAY_SIZE(smk_mount_opts); i++) {
89 size_t len = smk_mount_opts[i].len;
90 if (len > l || memcmp(s, smk_mount_opts[i].name, len))
91 continue;
92 if (len == l || s[len] != '=')
93 continue;
94 *arg = s + len + 1;
95 return smk_mount_opts[i].opt;
96 }
97 return Opt_error;
98}
99
100#ifdef CONFIG_SECURITY_SMACK_BRINGUP
101static char *smk_bu_mess[] = {
102 "Bringup Error", /* Unused */
103 "Bringup", /* SMACK_BRINGUP_ALLOW */
104 "Unconfined Subject", /* SMACK_UNCONFINED_SUBJECT */
105 "Unconfined Object", /* SMACK_UNCONFINED_OBJECT */
106};
107
108static void smk_bu_mode(int mode, char *s)
109{
110 int i = 0;
111
112 if (mode & MAY_READ)
113 s[i++] = 'r';
114 if (mode & MAY_WRITE)
115 s[i++] = 'w';
116 if (mode & MAY_EXEC)
117 s[i++] = 'x';
118 if (mode & MAY_APPEND)
119 s[i++] = 'a';
120 if (mode & MAY_TRANSMUTE)
121 s[i++] = 't';
122 if (mode & MAY_LOCK)
123 s[i++] = 'l';
124 if (i == 0)
125 s[i++] = '-';
126 s[i] = '\0';
127}
128#endif
129
130#ifdef CONFIG_SECURITY_SMACK_BRINGUP
131static int smk_bu_note(char *note, struct smack_known *sskp,
132 struct smack_known *oskp, int mode, int rc)
133{
134 char acc[SMK_NUM_ACCESS_TYPE + 1];
135
136 if (rc <= 0)
137 return rc;
138 if (rc > SMACK_UNCONFINED_OBJECT)
139 rc = 0;
140
141 smk_bu_mode(mode, acc);
142 pr_info("Smack %s: (%s %s %s) %s\n", smk_bu_mess[rc],
143 sskp->smk_known, oskp->smk_known, acc, note);
144 return 0;
145}
146#else
147#define smk_bu_note(note, sskp, oskp, mode, RC) (RC)
148#endif
149
150#ifdef CONFIG_SECURITY_SMACK_BRINGUP
151static int smk_bu_current(char *note, struct smack_known *oskp,
152 int mode, int rc)
153{
154 struct task_smack *tsp = smack_cred(current_cred());
155 char acc[SMK_NUM_ACCESS_TYPE + 1];
156
157 if (rc <= 0)
158 return rc;
159 if (rc > SMACK_UNCONFINED_OBJECT)
160 rc = 0;
161
162 smk_bu_mode(mode, acc);
163 pr_info("Smack %s: (%s %s %s) %s %s\n", smk_bu_mess[rc],
164 tsp->smk_task->smk_known, oskp->smk_known,
165 acc, current->comm, note);
166 return 0;
167}
168#else
169#define smk_bu_current(note, oskp, mode, RC) (RC)
170#endif
171
172#ifdef CONFIG_SECURITY_SMACK_BRINGUP
173static int smk_bu_task(struct task_struct *otp, int mode, int rc)
174{
175 struct task_smack *tsp = smack_cred(current_cred());
176 struct smack_known *smk_task = smk_of_task_struct_obj(otp);
177 char acc[SMK_NUM_ACCESS_TYPE + 1];
178
179 if (rc <= 0)
180 return rc;
181 if (rc > SMACK_UNCONFINED_OBJECT)
182 rc = 0;
183
184 smk_bu_mode(mode, acc);
185 pr_info("Smack %s: (%s %s %s) %s to %s\n", smk_bu_mess[rc],
186 tsp->smk_task->smk_known, smk_task->smk_known, acc,
187 current->comm, otp->comm);
188 return 0;
189}
190#else
191#define smk_bu_task(otp, mode, RC) (RC)
192#endif
193
194#ifdef CONFIG_SECURITY_SMACK_BRINGUP
195static int smk_bu_inode(struct inode *inode, int mode, int rc)
196{
197 struct task_smack *tsp = smack_cred(current_cred());
198 struct inode_smack *isp = smack_inode(inode);
199 char acc[SMK_NUM_ACCESS_TYPE + 1];
200
201 if (isp->smk_flags & SMK_INODE_IMPURE)
202 pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n",
203 inode->i_sb->s_id, inode->i_ino, current->comm);
204
205 if (rc <= 0)
206 return rc;
207 if (rc > SMACK_UNCONFINED_OBJECT)
208 rc = 0;
209 if (rc == SMACK_UNCONFINED_SUBJECT &&
210 (mode & (MAY_WRITE | MAY_APPEND)))
211 isp->smk_flags |= SMK_INODE_IMPURE;
212
213 smk_bu_mode(mode, acc);
214
215 pr_info("Smack %s: (%s %s %s) inode=(%s %ld) %s\n", smk_bu_mess[rc],
216 tsp->smk_task->smk_known, isp->smk_inode->smk_known, acc,
217 inode->i_sb->s_id, inode->i_ino, current->comm);
218 return 0;
219}
220#else
221#define smk_bu_inode(inode, mode, RC) (RC)
222#endif
223
224#ifdef CONFIG_SECURITY_SMACK_BRINGUP
225static int smk_bu_file(struct file *file, int mode, int rc)
226{
227 struct task_smack *tsp = smack_cred(current_cred());
228 struct smack_known *sskp = tsp->smk_task;
229 struct inode *inode = file_inode(file);
230 struct inode_smack *isp = smack_inode(inode);
231 char acc[SMK_NUM_ACCESS_TYPE + 1];
232
233 if (isp->smk_flags & SMK_INODE_IMPURE)
234 pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n",
235 inode->i_sb->s_id, inode->i_ino, current->comm);
236
237 if (rc <= 0)
238 return rc;
239 if (rc > SMACK_UNCONFINED_OBJECT)
240 rc = 0;
241
242 smk_bu_mode(mode, acc);
243 pr_info("Smack %s: (%s %s %s) file=(%s %ld %pD) %s\n", smk_bu_mess[rc],
244 sskp->smk_known, smk_of_inode(inode)->smk_known, acc,
245 inode->i_sb->s_id, inode->i_ino, file,
246 current->comm);
247 return 0;
248}
249#else
250#define smk_bu_file(file, mode, RC) (RC)
251#endif
252
253#ifdef CONFIG_SECURITY_SMACK_BRINGUP
254static int smk_bu_credfile(const struct cred *cred, struct file *file,
255 int mode, int rc)
256{
257 struct task_smack *tsp = smack_cred(cred);
258 struct smack_known *sskp = tsp->smk_task;
259 struct inode *inode = file_inode(file);
260 struct inode_smack *isp = smack_inode(inode);
261 char acc[SMK_NUM_ACCESS_TYPE + 1];
262
263 if (isp->smk_flags & SMK_INODE_IMPURE)
264 pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n",
265 inode->i_sb->s_id, inode->i_ino, current->comm);
266
267 if (rc <= 0)
268 return rc;
269 if (rc > SMACK_UNCONFINED_OBJECT)
270 rc = 0;
271
272 smk_bu_mode(mode, acc);
273 pr_info("Smack %s: (%s %s %s) file=(%s %ld %pD) %s\n", smk_bu_mess[rc],
274 sskp->smk_known, smk_of_inode(inode)->smk_known, acc,
275 inode->i_sb->s_id, inode->i_ino, file,
276 current->comm);
277 return 0;
278}
279#else
280#define smk_bu_credfile(cred, file, mode, RC) (RC)
281#endif
282
283/**
284 * smk_fetch - Fetch the smack label from a file.
285 * @name: type of the label (attribute)
286 * @ip: a pointer to the inode
287 * @dp: a pointer to the dentry
288 *
289 * Returns a pointer to the master list entry for the Smack label,
290 * NULL if there was no label to fetch, or an error code.
291 */
292static struct smack_known *smk_fetch(const char *name, struct inode *ip,
293 struct dentry *dp)
294{
295 int rc;
296 char *buffer;
297 struct smack_known *skp = NULL;
298
299 if (!(ip->i_opflags & IOP_XATTR))
300 return ERR_PTR(-EOPNOTSUPP);
301
302 buffer = kzalloc(SMK_LONGLABEL, GFP_NOFS);
303 if (buffer == NULL)
304 return ERR_PTR(-ENOMEM);
305
306 rc = __vfs_getxattr(dp, ip, name, buffer, SMK_LONGLABEL);
307 if (rc < 0)
308 skp = ERR_PTR(rc);
309 else if (rc == 0)
310 skp = NULL;
311 else
312 skp = smk_import_entry(buffer, rc);
313
314 kfree(buffer);
315
316 return skp;
317}
318
319/**
320 * init_inode_smack - initialize an inode security blob
321 * @inode: inode to extract the info from
322 * @skp: a pointer to the Smack label entry to use in the blob
323 *
324 */
325static void init_inode_smack(struct inode *inode, struct smack_known *skp)
326{
327 struct inode_smack *isp = smack_inode(inode);
328
329 isp->smk_inode = skp;
330 isp->smk_flags = 0;
331}
332
333/**
334 * init_task_smack - initialize a task security blob
335 * @tsp: blob to initialize
336 * @task: a pointer to the Smack label for the running task
337 * @forked: a pointer to the Smack label for the forked task
338 *
339 */
340static void init_task_smack(struct task_smack *tsp, struct smack_known *task,
341 struct smack_known *forked)
342{
343 tsp->smk_task = task;
344 tsp->smk_forked = forked;
345 INIT_LIST_HEAD(&tsp->smk_rules);
346 INIT_LIST_HEAD(&tsp->smk_relabel);
347 mutex_init(&tsp->smk_rules_lock);
348}
349
350/**
351 * smk_copy_rules - copy a rule set
352 * @nhead: new rules header pointer
353 * @ohead: old rules header pointer
354 * @gfp: type of the memory for the allocation
355 *
356 * Returns 0 on success, -ENOMEM on error
357 */
358static int smk_copy_rules(struct list_head *nhead, struct list_head *ohead,
359 gfp_t gfp)
360{
361 struct smack_rule *nrp;
362 struct smack_rule *orp;
363 int rc = 0;
364
365 list_for_each_entry_rcu(orp, ohead, list) {
366 nrp = kmem_cache_zalloc(smack_rule_cache, gfp);
367 if (nrp == NULL) {
368 rc = -ENOMEM;
369 break;
370 }
371 *nrp = *orp;
372 list_add_rcu(&nrp->list, nhead);
373 }
374 return rc;
375}
376
377/**
378 * smk_copy_relabel - copy smk_relabel labels list
379 * @nhead: new rules header pointer
380 * @ohead: old rules header pointer
381 * @gfp: type of the memory for the allocation
382 *
383 * Returns 0 on success, -ENOMEM on error
384 */
385static int smk_copy_relabel(struct list_head *nhead, struct list_head *ohead,
386 gfp_t gfp)
387{
388 struct smack_known_list_elem *nklep;
389 struct smack_known_list_elem *oklep;
390
391 list_for_each_entry(oklep, ohead, list) {
392 nklep = kzalloc(sizeof(struct smack_known_list_elem), gfp);
393 if (nklep == NULL) {
394 smk_destroy_label_list(nhead);
395 return -ENOMEM;
396 }
397 nklep->smk_label = oklep->smk_label;
398 list_add(&nklep->list, nhead);
399 }
400
401 return 0;
402}
403
404/**
405 * smk_ptrace_mode - helper function for converting PTRACE_MODE_* into MAY_*
406 * @mode: input mode in form of PTRACE_MODE_*
407 *
408 * Returns a converted MAY_* mode usable by smack rules
409 */
410static inline unsigned int smk_ptrace_mode(unsigned int mode)
411{
412 if (mode & PTRACE_MODE_ATTACH)
413 return MAY_READWRITE;
414 if (mode & PTRACE_MODE_READ)
415 return MAY_READ;
416
417 return 0;
418}
419
420/**
421 * smk_ptrace_rule_check - helper for ptrace access
422 * @tracer: tracer process
423 * @tracee_known: label entry of the process that's about to be traced
424 * @mode: ptrace attachment mode (PTRACE_MODE_*)
425 * @func: name of the function that called us, used for audit
426 *
427 * Returns 0 on access granted, -error on error
428 */
429static int smk_ptrace_rule_check(struct task_struct *tracer,
430 struct smack_known *tracee_known,
431 unsigned int mode, const char *func)
432{
433 int rc;
434 struct smk_audit_info ad, *saip = NULL;
435 struct task_smack *tsp;
436 struct smack_known *tracer_known;
437 const struct cred *tracercred;
438
439 if ((mode & PTRACE_MODE_NOAUDIT) == 0) {
440 smk_ad_init(&ad, func, LSM_AUDIT_DATA_TASK);
441 smk_ad_setfield_u_tsk(&ad, tracer);
442 saip = &ad;
443 }
444
445 rcu_read_lock();
446 tracercred = __task_cred(tracer);
447 tsp = smack_cred(tracercred);
448 tracer_known = smk_of_task(tsp);
449
450 if ((mode & PTRACE_MODE_ATTACH) &&
451 (smack_ptrace_rule == SMACK_PTRACE_EXACT ||
452 smack_ptrace_rule == SMACK_PTRACE_DRACONIAN)) {
453 if (tracer_known->smk_known == tracee_known->smk_known)
454 rc = 0;
455 else if (smack_ptrace_rule == SMACK_PTRACE_DRACONIAN)
456 rc = -EACCES;
457 else if (smack_privileged_cred(CAP_SYS_PTRACE, tracercred))
458 rc = 0;
459 else
460 rc = -EACCES;
461
462 if (saip)
463 smack_log(tracer_known->smk_known,
464 tracee_known->smk_known,
465 0, rc, saip);
466
467 rcu_read_unlock();
468 return rc;
469 }
470
471 /* In case of rule==SMACK_PTRACE_DEFAULT or mode==PTRACE_MODE_READ */
472 rc = smk_tskacc(tsp, tracee_known, smk_ptrace_mode(mode), saip);
473
474 rcu_read_unlock();
475 return rc;
476}
477
478/*
479 * LSM hooks.
480 * We he, that is fun!
481 */
482
483/**
484 * smack_ptrace_access_check - Smack approval on PTRACE_ATTACH
485 * @ctp: child task pointer
486 * @mode: ptrace attachment mode (PTRACE_MODE_*)
487 *
488 * Returns 0 if access is OK, an error code otherwise
489 *
490 * Do the capability checks.
491 */
492static int smack_ptrace_access_check(struct task_struct *ctp, unsigned int mode)
493{
494 struct smack_known *skp;
495
496 skp = smk_of_task_struct_obj(ctp);
497
498 return smk_ptrace_rule_check(current, skp, mode, __func__);
499}
500
501/**
502 * smack_ptrace_traceme - Smack approval on PTRACE_TRACEME
503 * @ptp: parent task pointer
504 *
505 * Returns 0 if access is OK, an error code otherwise
506 *
507 * Do the capability checks, and require PTRACE_MODE_ATTACH.
508 */
509static int smack_ptrace_traceme(struct task_struct *ptp)
510{
511 struct smack_known *skp;
512
513 skp = smk_of_task(smack_cred(current_cred()));
514
515 return smk_ptrace_rule_check(ptp, skp, PTRACE_MODE_ATTACH, __func__);
516}
517
518/**
519 * smack_syslog - Smack approval on syslog
520 * @typefrom_file: unused
521 *
522 * Returns 0 on success, error code otherwise.
523 */
524static int smack_syslog(int typefrom_file)
525{
526 int rc = 0;
527 struct smack_known *skp = smk_of_current();
528
529 if (smack_privileged(CAP_MAC_OVERRIDE))
530 return 0;
531
532 if (smack_syslog_label != NULL && smack_syslog_label != skp)
533 rc = -EACCES;
534
535 return rc;
536}
537
538/*
539 * Superblock Hooks.
540 */
541
542/**
543 * smack_sb_alloc_security - allocate a superblock blob
544 * @sb: the superblock getting the blob
545 *
546 * Returns 0 on success or -ENOMEM on error.
547 */
548static int smack_sb_alloc_security(struct super_block *sb)
549{
550 struct superblock_smack *sbsp = smack_superblock(sb);
551
552 sbsp->smk_root = &smack_known_floor;
553 sbsp->smk_default = &smack_known_floor;
554 sbsp->smk_floor = &smack_known_floor;
555 sbsp->smk_hat = &smack_known_hat;
556 /*
557 * SMK_SB_INITIALIZED will be zero from kzalloc.
558 */
559
560 return 0;
561}
562
563struct smack_mnt_opts {
564 const char *fsdefault;
565 const char *fsfloor;
566 const char *fshat;
567 const char *fsroot;
568 const char *fstransmute;
569};
570
571static void smack_free_mnt_opts(void *mnt_opts)
572{
573 kfree(mnt_opts);
574}
575
576static int smack_add_opt(int token, const char *s, void **mnt_opts)
577{
578 struct smack_mnt_opts *opts = *mnt_opts;
579 struct smack_known *skp;
580
581 if (!opts) {
582 opts = kzalloc(sizeof(struct smack_mnt_opts), GFP_KERNEL);
583 if (!opts)
584 return -ENOMEM;
585 *mnt_opts = opts;
586 }
587 if (!s)
588 return -ENOMEM;
589
590 skp = smk_import_entry(s, 0);
591 if (IS_ERR(skp))
592 return PTR_ERR(skp);
593
594 switch (token) {
595 case Opt_fsdefault:
596 if (opts->fsdefault)
597 goto out_opt_err;
598 opts->fsdefault = skp->smk_known;
599 break;
600 case Opt_fsfloor:
601 if (opts->fsfloor)
602 goto out_opt_err;
603 opts->fsfloor = skp->smk_known;
604 break;
605 case Opt_fshat:
606 if (opts->fshat)
607 goto out_opt_err;
608 opts->fshat = skp->smk_known;
609 break;
610 case Opt_fsroot:
611 if (opts->fsroot)
612 goto out_opt_err;
613 opts->fsroot = skp->smk_known;
614 break;
615 case Opt_fstransmute:
616 if (opts->fstransmute)
617 goto out_opt_err;
618 opts->fstransmute = skp->smk_known;
619 break;
620 }
621 return 0;
622
623out_opt_err:
624 pr_warn("Smack: duplicate mount options\n");
625 return -EINVAL;
626}
627
628/**
629 * smack_fs_context_submount - Initialise security data for a filesystem context
630 * @fc: The filesystem context.
631 * @reference: reference superblock
632 *
633 * Returns 0 on success or -ENOMEM on error.
634 */
635static int smack_fs_context_submount(struct fs_context *fc,
636 struct super_block *reference)
637{
638 struct superblock_smack *sbsp;
639 struct smack_mnt_opts *ctx;
640 struct inode_smack *isp;
641
642 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
643 if (!ctx)
644 return -ENOMEM;
645 fc->security = ctx;
646
647 sbsp = smack_superblock(reference);
648 isp = smack_inode(reference->s_root->d_inode);
649
650 if (sbsp->smk_default) {
651 ctx->fsdefault = kstrdup(sbsp->smk_default->smk_known, GFP_KERNEL);
652 if (!ctx->fsdefault)
653 return -ENOMEM;
654 }
655
656 if (sbsp->smk_floor) {
657 ctx->fsfloor = kstrdup(sbsp->smk_floor->smk_known, GFP_KERNEL);
658 if (!ctx->fsfloor)
659 return -ENOMEM;
660 }
661
662 if (sbsp->smk_hat) {
663 ctx->fshat = kstrdup(sbsp->smk_hat->smk_known, GFP_KERNEL);
664 if (!ctx->fshat)
665 return -ENOMEM;
666 }
667
668 if (isp->smk_flags & SMK_INODE_TRANSMUTE) {
669 if (sbsp->smk_root) {
670 ctx->fstransmute = kstrdup(sbsp->smk_root->smk_known, GFP_KERNEL);
671 if (!ctx->fstransmute)
672 return -ENOMEM;
673 }
674 }
675 return 0;
676}
677
678/**
679 * smack_fs_context_dup - Duplicate the security data on fs_context duplication
680 * @fc: The new filesystem context.
681 * @src_fc: The source filesystem context being duplicated.
682 *
683 * Returns 0 on success or -ENOMEM on error.
684 */
685static int smack_fs_context_dup(struct fs_context *fc,
686 struct fs_context *src_fc)
687{
688 struct smack_mnt_opts *dst, *src = src_fc->security;
689
690 if (!src)
691 return 0;
692
693 fc->security = kzalloc(sizeof(struct smack_mnt_opts), GFP_KERNEL);
694 if (!fc->security)
695 return -ENOMEM;
696
697 dst = fc->security;
698 dst->fsdefault = src->fsdefault;
699 dst->fsfloor = src->fsfloor;
700 dst->fshat = src->fshat;
701 dst->fsroot = src->fsroot;
702 dst->fstransmute = src->fstransmute;
703
704 return 0;
705}
706
707static const struct fs_parameter_spec smack_fs_parameters[] = {
708 fsparam_string("smackfsdef", Opt_fsdefault),
709 fsparam_string("smackfsdefault", Opt_fsdefault),
710 fsparam_string("smackfsfloor", Opt_fsfloor),
711 fsparam_string("smackfshat", Opt_fshat),
712 fsparam_string("smackfsroot", Opt_fsroot),
713 fsparam_string("smackfstransmute", Opt_fstransmute),
714 {}
715};
716
717/**
718 * smack_fs_context_parse_param - Parse a single mount parameter
719 * @fc: The new filesystem context being constructed.
720 * @param: The parameter.
721 *
722 * Returns 0 on success, -ENOPARAM to pass the parameter on or anything else on
723 * error.
724 */
725static int smack_fs_context_parse_param(struct fs_context *fc,
726 struct fs_parameter *param)
727{
728 struct fs_parse_result result;
729 int opt, rc;
730
731 opt = fs_parse(fc, smack_fs_parameters, param, &result);
732 if (opt < 0)
733 return opt;
734
735 rc = smack_add_opt(opt, param->string, &fc->security);
736 if (!rc)
737 param->string = NULL;
738 return rc;
739}
740
741static int smack_sb_eat_lsm_opts(char *options, void **mnt_opts)
742{
743 char *from = options, *to = options;
744 bool first = true;
745
746 while (1) {
747 char *next = strchr(from, ',');
748 int token, len, rc;
749 char *arg = NULL;
750
751 if (next)
752 len = next - from;
753 else
754 len = strlen(from);
755
756 token = match_opt_prefix(from, len, &arg);
757 if (token != Opt_error) {
758 arg = kmemdup_nul(arg, from + len - arg, GFP_KERNEL);
759 rc = smack_add_opt(token, arg, mnt_opts);
760 kfree(arg);
761 if (unlikely(rc)) {
762 if (*mnt_opts)
763 smack_free_mnt_opts(*mnt_opts);
764 *mnt_opts = NULL;
765 return rc;
766 }
767 } else {
768 if (!first) { // copy with preceding comma
769 from--;
770 len++;
771 }
772 if (to != from)
773 memmove(to, from, len);
774 to += len;
775 first = false;
776 }
777 if (!from[len])
778 break;
779 from += len + 1;
780 }
781 *to = '\0';
782 return 0;
783}
784
785/**
786 * smack_set_mnt_opts - set Smack specific mount options
787 * @sb: the file system superblock
788 * @mnt_opts: Smack mount options
789 * @kern_flags: mount option from kernel space or user space
790 * @set_kern_flags: where to store converted mount opts
791 *
792 * Returns 0 on success, an error code on failure
793 *
794 * Allow filesystems with binary mount data to explicitly set Smack mount
795 * labels.
796 */
797static int smack_set_mnt_opts(struct super_block *sb,
798 void *mnt_opts,
799 unsigned long kern_flags,
800 unsigned long *set_kern_flags)
801{
802 struct dentry *root = sb->s_root;
803 struct inode *inode = d_backing_inode(root);
804 struct superblock_smack *sp = smack_superblock(sb);
805 struct inode_smack *isp;
806 struct smack_known *skp;
807 struct smack_mnt_opts *opts = mnt_opts;
808 bool transmute = false;
809
810 if (sp->smk_flags & SMK_SB_INITIALIZED)
811 return 0;
812
813 if (!smack_privileged(CAP_MAC_ADMIN)) {
814 /*
815 * Unprivileged mounts don't get to specify Smack values.
816 */
817 if (opts)
818 return -EPERM;
819 /*
820 * Unprivileged mounts get root and default from the caller.
821 */
822 skp = smk_of_current();
823 sp->smk_root = skp;
824 sp->smk_default = skp;
825 /*
826 * For a handful of fs types with no user-controlled
827 * backing store it's okay to trust security labels
828 * in the filesystem. The rest are untrusted.
829 */
830 if (sb->s_user_ns != &init_user_ns &&
831 sb->s_magic != SYSFS_MAGIC && sb->s_magic != TMPFS_MAGIC &&
832 sb->s_magic != RAMFS_MAGIC) {
833 transmute = true;
834 sp->smk_flags |= SMK_SB_UNTRUSTED;
835 }
836 }
837
838 sp->smk_flags |= SMK_SB_INITIALIZED;
839
840 if (opts) {
841 if (opts->fsdefault) {
842 skp = smk_import_entry(opts->fsdefault, 0);
843 if (IS_ERR(skp))
844 return PTR_ERR(skp);
845 sp->smk_default = skp;
846 }
847 if (opts->fsfloor) {
848 skp = smk_import_entry(opts->fsfloor, 0);
849 if (IS_ERR(skp))
850 return PTR_ERR(skp);
851 sp->smk_floor = skp;
852 }
853 if (opts->fshat) {
854 skp = smk_import_entry(opts->fshat, 0);
855 if (IS_ERR(skp))
856 return PTR_ERR(skp);
857 sp->smk_hat = skp;
858 }
859 if (opts->fsroot) {
860 skp = smk_import_entry(opts->fsroot, 0);
861 if (IS_ERR(skp))
862 return PTR_ERR(skp);
863 sp->smk_root = skp;
864 }
865 if (opts->fstransmute) {
866 skp = smk_import_entry(opts->fstransmute, 0);
867 if (IS_ERR(skp))
868 return PTR_ERR(skp);
869 sp->smk_root = skp;
870 transmute = true;
871 }
872 }
873
874 /*
875 * Initialize the root inode.
876 */
877 init_inode_smack(inode, sp->smk_root);
878
879 if (transmute) {
880 isp = smack_inode(inode);
881 isp->smk_flags |= SMK_INODE_TRANSMUTE;
882 }
883
884 return 0;
885}
886
887/**
888 * smack_sb_statfs - Smack check on statfs
889 * @dentry: identifies the file system in question
890 *
891 * Returns 0 if current can read the floor of the filesystem,
892 * and error code otherwise
893 */
894static int smack_sb_statfs(struct dentry *dentry)
895{
896 struct superblock_smack *sbp = smack_superblock(dentry->d_sb);
897 int rc;
898 struct smk_audit_info ad;
899
900 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
901 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
902
903 rc = smk_curacc(sbp->smk_floor, MAY_READ, &ad);
904 rc = smk_bu_current("statfs", sbp->smk_floor, MAY_READ, rc);
905 return rc;
906}
907
908/*
909 * BPRM hooks
910 */
911
912/**
913 * smack_bprm_creds_for_exec - Update bprm->cred if needed for exec
914 * @bprm: the exec information
915 *
916 * Returns 0 if it gets a blob, -EPERM if exec forbidden and -ENOMEM otherwise
917 */
918static int smack_bprm_creds_for_exec(struct linux_binprm *bprm)
919{
920 struct inode *inode = file_inode(bprm->file);
921 struct task_smack *bsp = smack_cred(bprm->cred);
922 struct inode_smack *isp;
923 struct superblock_smack *sbsp;
924 int rc;
925
926 isp = smack_inode(inode);
927 if (isp->smk_task == NULL || isp->smk_task == bsp->smk_task)
928 return 0;
929
930 sbsp = smack_superblock(inode->i_sb);
931 if ((sbsp->smk_flags & SMK_SB_UNTRUSTED) &&
932 isp->smk_task != sbsp->smk_root)
933 return 0;
934
935 if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
936 struct task_struct *tracer;
937 rc = 0;
938
939 rcu_read_lock();
940 tracer = ptrace_parent(current);
941 if (likely(tracer != NULL))
942 rc = smk_ptrace_rule_check(tracer,
943 isp->smk_task,
944 PTRACE_MODE_ATTACH,
945 __func__);
946 rcu_read_unlock();
947
948 if (rc != 0)
949 return rc;
950 }
951 if (bprm->unsafe & ~LSM_UNSAFE_PTRACE)
952 return -EPERM;
953
954 bsp->smk_task = isp->smk_task;
955 bprm->per_clear |= PER_CLEAR_ON_SETID;
956
957 /* Decide if this is a secure exec. */
958 if (bsp->smk_task != bsp->smk_forked)
959 bprm->secureexec = 1;
960
961 return 0;
962}
963
964/*
965 * Inode hooks
966 */
967
968/**
969 * smack_inode_alloc_security - allocate an inode blob
970 * @inode: the inode in need of a blob
971 *
972 * Returns 0
973 */
974static int smack_inode_alloc_security(struct inode *inode)
975{
976 struct smack_known *skp = smk_of_current();
977
978 init_inode_smack(inode, skp);
979 return 0;
980}
981
982/**
983 * smack_inode_init_security - copy out the smack from an inode
984 * @inode: the newly created inode
985 * @dir: containing directory object
986 * @qstr: unused
987 * @xattrs: where to put the attributes
988 * @xattr_count: current number of LSM-provided xattrs (updated)
989 *
990 * Returns 0 if it all works out, -ENOMEM if there's no memory
991 */
992static int smack_inode_init_security(struct inode *inode, struct inode *dir,
993 const struct qstr *qstr,
994 struct xattr *xattrs, int *xattr_count)
995{
996 struct task_smack *tsp = smack_cred(current_cred());
997 struct inode_smack *issp = smack_inode(inode);
998 struct smack_known *skp = smk_of_task(tsp);
999 struct smack_known *isp = smk_of_inode(inode);
1000 struct smack_known *dsp = smk_of_inode(dir);
1001 struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count);
1002 int may;
1003
1004 /*
1005 * If equal, transmuting already occurred in
1006 * smack_dentry_create_files_as(). No need to check again.
1007 */
1008 if (tsp->smk_task != tsp->smk_transmuted) {
1009 rcu_read_lock();
1010 may = smk_access_entry(skp->smk_known, dsp->smk_known,
1011 &skp->smk_rules);
1012 rcu_read_unlock();
1013 }
1014
1015 /*
1016 * In addition to having smk_task equal to smk_transmuted,
1017 * if the access rule allows transmutation and the directory
1018 * requests transmutation then by all means transmute.
1019 * Mark the inode as changed.
1020 */
1021 if ((tsp->smk_task == tsp->smk_transmuted) ||
1022 (may > 0 && ((may & MAY_TRANSMUTE) != 0) &&
1023 smk_inode_transmutable(dir))) {
1024 struct xattr *xattr_transmute;
1025
1026 /*
1027 * The caller of smack_dentry_create_files_as()
1028 * should have overridden the current cred, so the
1029 * inode label was already set correctly in
1030 * smack_inode_alloc_security().
1031 */
1032 if (tsp->smk_task != tsp->smk_transmuted)
1033 isp = issp->smk_inode = dsp;
1034
1035 issp->smk_flags |= SMK_INODE_TRANSMUTE;
1036 xattr_transmute = lsm_get_xattr_slot(xattrs,
1037 xattr_count);
1038 if (xattr_transmute) {
1039 xattr_transmute->value = kmemdup(TRANS_TRUE,
1040 TRANS_TRUE_SIZE,
1041 GFP_NOFS);
1042 if (!xattr_transmute->value)
1043 return -ENOMEM;
1044
1045 xattr_transmute->value_len = TRANS_TRUE_SIZE;
1046 xattr_transmute->name = XATTR_SMACK_TRANSMUTE;
1047 }
1048 }
1049
1050 issp->smk_flags |= SMK_INODE_INSTANT;
1051
1052 if (xattr) {
1053 xattr->value = kstrdup(isp->smk_known, GFP_NOFS);
1054 if (!xattr->value)
1055 return -ENOMEM;
1056
1057 xattr->value_len = strlen(isp->smk_known);
1058 xattr->name = XATTR_SMACK_SUFFIX;
1059 }
1060
1061 return 0;
1062}
1063
1064/**
1065 * smack_inode_link - Smack check on link
1066 * @old_dentry: the existing object
1067 * @dir: unused
1068 * @new_dentry: the new object
1069 *
1070 * Returns 0 if access is permitted, an error code otherwise
1071 */
1072static int smack_inode_link(struct dentry *old_dentry, struct inode *dir,
1073 struct dentry *new_dentry)
1074{
1075 struct smack_known *isp;
1076 struct smk_audit_info ad;
1077 int rc;
1078
1079 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1080 smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
1081
1082 isp = smk_of_inode(d_backing_inode(old_dentry));
1083 rc = smk_curacc(isp, MAY_WRITE, &ad);
1084 rc = smk_bu_inode(d_backing_inode(old_dentry), MAY_WRITE, rc);
1085
1086 if (rc == 0 && d_is_positive(new_dentry)) {
1087 isp = smk_of_inode(d_backing_inode(new_dentry));
1088 smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
1089 rc = smk_curacc(isp, MAY_WRITE, &ad);
1090 rc = smk_bu_inode(d_backing_inode(new_dentry), MAY_WRITE, rc);
1091 }
1092
1093 return rc;
1094}
1095
1096/**
1097 * smack_inode_unlink - Smack check on inode deletion
1098 * @dir: containing directory object
1099 * @dentry: file to unlink
1100 *
1101 * Returns 0 if current can write the containing directory
1102 * and the object, error code otherwise
1103 */
1104static int smack_inode_unlink(struct inode *dir, struct dentry *dentry)
1105{
1106 struct inode *ip = d_backing_inode(dentry);
1107 struct smk_audit_info ad;
1108 int rc;
1109
1110 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1111 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1112
1113 /*
1114 * You need write access to the thing you're unlinking
1115 */
1116 rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad);
1117 rc = smk_bu_inode(ip, MAY_WRITE, rc);
1118 if (rc == 0) {
1119 /*
1120 * You also need write access to the containing directory
1121 */
1122 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
1123 smk_ad_setfield_u_fs_inode(&ad, dir);
1124 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
1125 rc = smk_bu_inode(dir, MAY_WRITE, rc);
1126 }
1127 return rc;
1128}
1129
1130/**
1131 * smack_inode_rmdir - Smack check on directory deletion
1132 * @dir: containing directory object
1133 * @dentry: directory to unlink
1134 *
1135 * Returns 0 if current can write the containing directory
1136 * and the directory, error code otherwise
1137 */
1138static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry)
1139{
1140 struct smk_audit_info ad;
1141 int rc;
1142
1143 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1144 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1145
1146 /*
1147 * You need write access to the thing you're removing
1148 */
1149 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1150 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1151 if (rc == 0) {
1152 /*
1153 * You also need write access to the containing directory
1154 */
1155 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
1156 smk_ad_setfield_u_fs_inode(&ad, dir);
1157 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
1158 rc = smk_bu_inode(dir, MAY_WRITE, rc);
1159 }
1160
1161 return rc;
1162}
1163
1164/**
1165 * smack_inode_rename - Smack check on rename
1166 * @old_inode: unused
1167 * @old_dentry: the old object
1168 * @new_inode: unused
1169 * @new_dentry: the new object
1170 *
1171 * Read and write access is required on both the old and
1172 * new directories.
1173 *
1174 * Returns 0 if access is permitted, an error code otherwise
1175 */
1176static int smack_inode_rename(struct inode *old_inode,
1177 struct dentry *old_dentry,
1178 struct inode *new_inode,
1179 struct dentry *new_dentry)
1180{
1181 int rc;
1182 struct smack_known *isp;
1183 struct smk_audit_info ad;
1184
1185 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1186 smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
1187
1188 isp = smk_of_inode(d_backing_inode(old_dentry));
1189 rc = smk_curacc(isp, MAY_READWRITE, &ad);
1190 rc = smk_bu_inode(d_backing_inode(old_dentry), MAY_READWRITE, rc);
1191
1192 if (rc == 0 && d_is_positive(new_dentry)) {
1193 isp = smk_of_inode(d_backing_inode(new_dentry));
1194 smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
1195 rc = smk_curacc(isp, MAY_READWRITE, &ad);
1196 rc = smk_bu_inode(d_backing_inode(new_dentry), MAY_READWRITE, rc);
1197 }
1198 return rc;
1199}
1200
1201/**
1202 * smack_inode_permission - Smack version of permission()
1203 * @inode: the inode in question
1204 * @mask: the access requested
1205 *
1206 * This is the important Smack hook.
1207 *
1208 * Returns 0 if access is permitted, an error code otherwise
1209 */
1210static int smack_inode_permission(struct inode *inode, int mask)
1211{
1212 struct superblock_smack *sbsp = smack_superblock(inode->i_sb);
1213 struct smk_audit_info ad;
1214 int no_block = mask & MAY_NOT_BLOCK;
1215 int rc;
1216
1217 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
1218 /*
1219 * No permission to check. Existence test. Yup, it's there.
1220 */
1221 if (mask == 0)
1222 return 0;
1223
1224 if (sbsp->smk_flags & SMK_SB_UNTRUSTED) {
1225 if (smk_of_inode(inode) != sbsp->smk_root)
1226 return -EACCES;
1227 }
1228
1229 /* May be droppable after audit */
1230 if (no_block)
1231 return -ECHILD;
1232 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
1233 smk_ad_setfield_u_fs_inode(&ad, inode);
1234 rc = smk_curacc(smk_of_inode(inode), mask, &ad);
1235 rc = smk_bu_inode(inode, mask, rc);
1236 return rc;
1237}
1238
1239/**
1240 * smack_inode_setattr - Smack check for setting attributes
1241 * @idmap: idmap of the mount
1242 * @dentry: the object
1243 * @iattr: for the force flag
1244 *
1245 * Returns 0 if access is permitted, an error code otherwise
1246 */
1247static int smack_inode_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
1248 struct iattr *iattr)
1249{
1250 struct smk_audit_info ad;
1251 int rc;
1252
1253 /*
1254 * Need to allow for clearing the setuid bit.
1255 */
1256 if (iattr->ia_valid & ATTR_FORCE)
1257 return 0;
1258 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1259 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1260
1261 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1262 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1263 return rc;
1264}
1265
1266/**
1267 * smack_inode_getattr - Smack check for getting attributes
1268 * @path: path to extract the info from
1269 *
1270 * Returns 0 if access is permitted, an error code otherwise
1271 */
1272static int smack_inode_getattr(const struct path *path)
1273{
1274 struct smk_audit_info ad;
1275 struct inode *inode = d_backing_inode(path->dentry);
1276 int rc;
1277
1278 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1279 smk_ad_setfield_u_fs_path(&ad, *path);
1280 rc = smk_curacc(smk_of_inode(inode), MAY_READ, &ad);
1281 rc = smk_bu_inode(inode, MAY_READ, rc);
1282 return rc;
1283}
1284
1285/**
1286 * smack_inode_xattr_skipcap - Skip the xattr capability checks?
1287 * @name: name of the xattr
1288 *
1289 * Returns 1 to indicate that Smack "owns" the access control rights to xattrs
1290 * named @name; the LSM layer should avoid enforcing any traditional
1291 * capability based access controls on this xattr. Returns 0 to indicate that
1292 * Smack does not "own" the access control rights to xattrs named @name and is
1293 * deferring to the LSM layer for further access controls, including capability
1294 * based controls.
1295 */
1296static int smack_inode_xattr_skipcap(const char *name)
1297{
1298 if (strncmp(name, XATTR_SMACK_SUFFIX, strlen(XATTR_SMACK_SUFFIX)))
1299 return 0;
1300
1301 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
1302 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
1303 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
1304 strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
1305 strcmp(name, XATTR_NAME_SMACKMMAP) == 0 ||
1306 strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0)
1307 return 1;
1308
1309 return 0;
1310}
1311
1312/**
1313 * smack_inode_setxattr - Smack check for setting xattrs
1314 * @idmap: idmap of the mount
1315 * @dentry: the object
1316 * @name: name of the attribute
1317 * @value: value of the attribute
1318 * @size: size of the value
1319 * @flags: unused
1320 *
1321 * This protects the Smack attribute explicitly.
1322 *
1323 * Returns 0 if access is permitted, an error code otherwise
1324 */
1325static int smack_inode_setxattr(struct mnt_idmap *idmap,
1326 struct dentry *dentry, const char *name,
1327 const void *value, size_t size, int flags)
1328{
1329 struct smk_audit_info ad;
1330 struct smack_known *skp;
1331 int check_priv = 0;
1332 int check_import = 0;
1333 int check_star = 0;
1334 int rc = 0;
1335
1336 /*
1337 * Check label validity here so import won't fail in post_setxattr
1338 */
1339 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
1340 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
1341 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) {
1342 check_priv = 1;
1343 check_import = 1;
1344 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
1345 strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1346 check_priv = 1;
1347 check_import = 1;
1348 check_star = 1;
1349 } else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
1350 check_priv = 1;
1351 if (!S_ISDIR(d_backing_inode(dentry)->i_mode) ||
1352 size != TRANS_TRUE_SIZE ||
1353 strncmp(value, TRANS_TRUE, TRANS_TRUE_SIZE) != 0)
1354 rc = -EINVAL;
1355 }
1356
1357 if (check_priv && !smack_privileged(CAP_MAC_ADMIN))
1358 rc = -EPERM;
1359
1360 if (rc == 0 && check_import) {
1361 skp = size ? smk_import_entry(value, size) : NULL;
1362 if (IS_ERR(skp))
1363 rc = PTR_ERR(skp);
1364 else if (skp == NULL || (check_star &&
1365 (skp == &smack_known_star || skp == &smack_known_web)))
1366 rc = -EINVAL;
1367 }
1368
1369 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1370 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1371
1372 if (rc == 0) {
1373 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1374 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1375 }
1376
1377 return rc;
1378}
1379
1380/**
1381 * smack_inode_post_setxattr - Apply the Smack update approved above
1382 * @dentry: object
1383 * @name: attribute name
1384 * @value: attribute value
1385 * @size: attribute size
1386 * @flags: unused
1387 *
1388 * Set the pointer in the inode blob to the entry found
1389 * in the master label list.
1390 */
1391static void smack_inode_post_setxattr(struct dentry *dentry, const char *name,
1392 const void *value, size_t size, int flags)
1393{
1394 struct smack_known *skp;
1395 struct inode_smack *isp = smack_inode(d_backing_inode(dentry));
1396
1397 if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
1398 isp->smk_flags |= SMK_INODE_TRANSMUTE;
1399 return;
1400 }
1401
1402 if (strcmp(name, XATTR_NAME_SMACK) == 0) {
1403 skp = smk_import_entry(value, size);
1404 if (!IS_ERR(skp))
1405 isp->smk_inode = skp;
1406 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0) {
1407 skp = smk_import_entry(value, size);
1408 if (!IS_ERR(skp))
1409 isp->smk_task = skp;
1410 } else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1411 skp = smk_import_entry(value, size);
1412 if (!IS_ERR(skp))
1413 isp->smk_mmap = skp;
1414 }
1415
1416 return;
1417}
1418
1419/**
1420 * smack_inode_getxattr - Smack check on getxattr
1421 * @dentry: the object
1422 * @name: unused
1423 *
1424 * Returns 0 if access is permitted, an error code otherwise
1425 */
1426static int smack_inode_getxattr(struct dentry *dentry, const char *name)
1427{
1428 struct smk_audit_info ad;
1429 int rc;
1430
1431 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1432 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1433
1434 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_READ, &ad);
1435 rc = smk_bu_inode(d_backing_inode(dentry), MAY_READ, rc);
1436 return rc;
1437}
1438
1439/**
1440 * smack_inode_removexattr - Smack check on removexattr
1441 * @idmap: idmap of the mount
1442 * @dentry: the object
1443 * @name: name of the attribute
1444 *
1445 * Removing the Smack attribute requires CAP_MAC_ADMIN
1446 *
1447 * Returns 0 if access is permitted, an error code otherwise
1448 */
1449static int smack_inode_removexattr(struct mnt_idmap *idmap,
1450 struct dentry *dentry, const char *name)
1451{
1452 struct inode_smack *isp;
1453 struct smk_audit_info ad;
1454 int rc = 0;
1455
1456 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
1457 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
1458 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
1459 strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
1460 strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0 ||
1461 strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1462 if (!smack_privileged(CAP_MAC_ADMIN))
1463 rc = -EPERM;
1464 }
1465
1466 if (rc != 0)
1467 return rc;
1468
1469 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1470 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1471
1472 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1473 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1474 if (rc != 0)
1475 return rc;
1476
1477 isp = smack_inode(d_backing_inode(dentry));
1478 /*
1479 * Don't do anything special for these.
1480 * XATTR_NAME_SMACKIPIN
1481 * XATTR_NAME_SMACKIPOUT
1482 */
1483 if (strcmp(name, XATTR_NAME_SMACK) == 0) {
1484 struct super_block *sbp = dentry->d_sb;
1485 struct superblock_smack *sbsp = smack_superblock(sbp);
1486
1487 isp->smk_inode = sbsp->smk_default;
1488 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0)
1489 isp->smk_task = NULL;
1490 else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0)
1491 isp->smk_mmap = NULL;
1492 else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0)
1493 isp->smk_flags &= ~SMK_INODE_TRANSMUTE;
1494
1495 return 0;
1496}
1497
1498/**
1499 * smack_inode_set_acl - Smack check for setting posix acls
1500 * @idmap: idmap of the mnt this request came from
1501 * @dentry: the object
1502 * @acl_name: name of the posix acl
1503 * @kacl: the posix acls
1504 *
1505 * Returns 0 if access is permitted, an error code otherwise
1506 */
1507static int smack_inode_set_acl(struct mnt_idmap *idmap,
1508 struct dentry *dentry, const char *acl_name,
1509 struct posix_acl *kacl)
1510{
1511 struct smk_audit_info ad;
1512 int rc;
1513
1514 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1515 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1516
1517 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1518 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1519 return rc;
1520}
1521
1522/**
1523 * smack_inode_get_acl - Smack check for getting posix acls
1524 * @idmap: idmap of the mnt this request came from
1525 * @dentry: the object
1526 * @acl_name: name of the posix acl
1527 *
1528 * Returns 0 if access is permitted, an error code otherwise
1529 */
1530static int smack_inode_get_acl(struct mnt_idmap *idmap,
1531 struct dentry *dentry, const char *acl_name)
1532{
1533 struct smk_audit_info ad;
1534 int rc;
1535
1536 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1537 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1538
1539 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_READ, &ad);
1540 rc = smk_bu_inode(d_backing_inode(dentry), MAY_READ, rc);
1541 return rc;
1542}
1543
1544/**
1545 * smack_inode_remove_acl - Smack check for getting posix acls
1546 * @idmap: idmap of the mnt this request came from
1547 * @dentry: the object
1548 * @acl_name: name of the posix acl
1549 *
1550 * Returns 0 if access is permitted, an error code otherwise
1551 */
1552static int smack_inode_remove_acl(struct mnt_idmap *idmap,
1553 struct dentry *dentry, const char *acl_name)
1554{
1555 struct smk_audit_info ad;
1556 int rc;
1557
1558 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1559 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1560
1561 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1562 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1563 return rc;
1564}
1565
1566/**
1567 * smack_inode_getsecurity - get smack xattrs
1568 * @idmap: idmap of the mount
1569 * @inode: the object
1570 * @name: attribute name
1571 * @buffer: where to put the result
1572 * @alloc: duplicate memory
1573 *
1574 * Returns the size of the attribute or an error code
1575 */
1576static int smack_inode_getsecurity(struct mnt_idmap *idmap,
1577 struct inode *inode, const char *name,
1578 void **buffer, bool alloc)
1579{
1580 struct socket_smack *ssp;
1581 struct socket *sock;
1582 struct super_block *sbp;
1583 struct inode *ip = inode;
1584 struct smack_known *isp;
1585 struct inode_smack *ispp;
1586 size_t label_len;
1587 char *label = NULL;
1588
1589 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
1590 isp = smk_of_inode(inode);
1591 } else if (strcmp(name, XATTR_SMACK_TRANSMUTE) == 0) {
1592 ispp = smack_inode(inode);
1593 if (ispp->smk_flags & SMK_INODE_TRANSMUTE)
1594 label = TRANS_TRUE;
1595 else
1596 label = "";
1597 } else {
1598 /*
1599 * The rest of the Smack xattrs are only on sockets.
1600 */
1601 sbp = ip->i_sb;
1602 if (sbp->s_magic != SOCKFS_MAGIC)
1603 return -EOPNOTSUPP;
1604
1605 sock = SOCKET_I(ip);
1606 if (sock == NULL || sock->sk == NULL)
1607 return -EOPNOTSUPP;
1608
1609 ssp = smack_sock(sock->sk);
1610
1611 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
1612 isp = ssp->smk_in;
1613 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0)
1614 isp = ssp->smk_out;
1615 else
1616 return -EOPNOTSUPP;
1617 }
1618
1619 if (!label)
1620 label = isp->smk_known;
1621
1622 label_len = strlen(label);
1623
1624 if (alloc) {
1625 *buffer = kstrdup(label, GFP_KERNEL);
1626 if (*buffer == NULL)
1627 return -ENOMEM;
1628 }
1629
1630 return label_len;
1631}
1632
1633
1634/**
1635 * smack_inode_listsecurity - list the Smack attributes
1636 * @inode: the object
1637 * @buffer: where they go
1638 * @buffer_size: size of buffer
1639 */
1640static int smack_inode_listsecurity(struct inode *inode, char *buffer,
1641 size_t buffer_size)
1642{
1643 int len = sizeof(XATTR_NAME_SMACK);
1644
1645 if (buffer != NULL && len <= buffer_size)
1646 memcpy(buffer, XATTR_NAME_SMACK, len);
1647
1648 return len;
1649}
1650
1651/**
1652 * smack_inode_getlsmprop - Extract inode's security id
1653 * @inode: inode to extract the info from
1654 * @prop: where result will be saved
1655 */
1656static void smack_inode_getlsmprop(struct inode *inode, struct lsm_prop *prop)
1657{
1658 prop->smack.skp = smk_of_inode(inode);
1659}
1660
1661/*
1662 * File Hooks
1663 */
1664
1665/*
1666 * There is no smack_file_permission hook
1667 *
1668 * Should access checks be done on each read or write?
1669 * UNICOS and SELinux say yes.
1670 * Trusted Solaris, Trusted Irix, and just about everyone else says no.
1671 *
1672 * I'll say no for now. Smack does not do the frequent
1673 * label changing that SELinux does.
1674 */
1675
1676/**
1677 * smack_file_alloc_security - assign a file security blob
1678 * @file: the object
1679 *
1680 * The security blob for a file is a pointer to the master
1681 * label list, so no allocation is done.
1682 *
1683 * f_security is the owner security information. It
1684 * isn't used on file access checks, it's for send_sigio.
1685 *
1686 * Returns 0
1687 */
1688static int smack_file_alloc_security(struct file *file)
1689{
1690 struct smack_known **blob = smack_file(file);
1691
1692 *blob = smk_of_current();
1693 return 0;
1694}
1695
1696/**
1697 * smack_file_ioctl - Smack check on ioctls
1698 * @file: the object
1699 * @cmd: what to do
1700 * @arg: unused
1701 *
1702 * Relies heavily on the correct use of the ioctl command conventions.
1703 *
1704 * Returns 0 if allowed, error code otherwise
1705 */
1706static int smack_file_ioctl(struct file *file, unsigned int cmd,
1707 unsigned long arg)
1708{
1709 int rc = 0;
1710 struct smk_audit_info ad;
1711 struct inode *inode = file_inode(file);
1712
1713 if (unlikely(IS_PRIVATE(inode)))
1714 return 0;
1715
1716 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1717 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1718
1719 if (_IOC_DIR(cmd) & _IOC_WRITE) {
1720 rc = smk_curacc(smk_of_inode(inode), MAY_WRITE, &ad);
1721 rc = smk_bu_file(file, MAY_WRITE, rc);
1722 }
1723
1724 if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ)) {
1725 rc = smk_curacc(smk_of_inode(inode), MAY_READ, &ad);
1726 rc = smk_bu_file(file, MAY_READ, rc);
1727 }
1728
1729 return rc;
1730}
1731
1732/**
1733 * smack_file_lock - Smack check on file locking
1734 * @file: the object
1735 * @cmd: unused
1736 *
1737 * Returns 0 if current has lock access, error code otherwise
1738 */
1739static int smack_file_lock(struct file *file, unsigned int cmd)
1740{
1741 struct smk_audit_info ad;
1742 int rc;
1743 struct inode *inode = file_inode(file);
1744
1745 if (unlikely(IS_PRIVATE(inode)))
1746 return 0;
1747
1748 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1749 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1750 rc = smk_curacc(smk_of_inode(inode), MAY_LOCK, &ad);
1751 rc = smk_bu_file(file, MAY_LOCK, rc);
1752 return rc;
1753}
1754
1755/**
1756 * smack_file_fcntl - Smack check on fcntl
1757 * @file: the object
1758 * @cmd: what action to check
1759 * @arg: unused
1760 *
1761 * Generally these operations are harmless.
1762 * File locking operations present an obvious mechanism
1763 * for passing information, so they require write access.
1764 *
1765 * Returns 0 if current has access, error code otherwise
1766 */
1767static int smack_file_fcntl(struct file *file, unsigned int cmd,
1768 unsigned long arg)
1769{
1770 struct smk_audit_info ad;
1771 int rc = 0;
1772 struct inode *inode = file_inode(file);
1773
1774 if (unlikely(IS_PRIVATE(inode)))
1775 return 0;
1776
1777 switch (cmd) {
1778 case F_GETLK:
1779 break;
1780 case F_SETLK:
1781 case F_SETLKW:
1782 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1783 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1784 rc = smk_curacc(smk_of_inode(inode), MAY_LOCK, &ad);
1785 rc = smk_bu_file(file, MAY_LOCK, rc);
1786 break;
1787 case F_SETOWN:
1788 case F_SETSIG:
1789 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1790 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1791 rc = smk_curacc(smk_of_inode(inode), MAY_WRITE, &ad);
1792 rc = smk_bu_file(file, MAY_WRITE, rc);
1793 break;
1794 default:
1795 break;
1796 }
1797
1798 return rc;
1799}
1800
1801/**
1802 * smack_mmap_file - Check permissions for a mmap operation.
1803 * @file: contains the file structure for file to map (may be NULL).
1804 * @reqprot: contains the protection requested by the application.
1805 * @prot: contains the protection that will be applied by the kernel.
1806 * @flags: contains the operational flags.
1807 *
1808 * The @file may be NULL, e.g. if mapping anonymous memory.
1809 *
1810 * Return 0 if permission is granted.
1811 */
1812static int smack_mmap_file(struct file *file,
1813 unsigned long reqprot, unsigned long prot,
1814 unsigned long flags)
1815{
1816 struct smack_known *skp;
1817 struct smack_known *mkp;
1818 struct smack_rule *srp;
1819 struct task_smack *tsp;
1820 struct smack_known *okp;
1821 struct inode_smack *isp;
1822 struct superblock_smack *sbsp;
1823 int may;
1824 int mmay;
1825 int tmay;
1826 int rc;
1827
1828 if (file == NULL)
1829 return 0;
1830
1831 if (unlikely(IS_PRIVATE(file_inode(file))))
1832 return 0;
1833
1834 isp = smack_inode(file_inode(file));
1835 if (isp->smk_mmap == NULL)
1836 return 0;
1837 sbsp = smack_superblock(file_inode(file)->i_sb);
1838 if (sbsp->smk_flags & SMK_SB_UNTRUSTED &&
1839 isp->smk_mmap != sbsp->smk_root)
1840 return -EACCES;
1841 mkp = isp->smk_mmap;
1842
1843 tsp = smack_cred(current_cred());
1844 skp = smk_of_current();
1845 rc = 0;
1846
1847 rcu_read_lock();
1848 /*
1849 * For each Smack rule associated with the subject
1850 * label verify that the SMACK64MMAP also has access
1851 * to that rule's object label.
1852 */
1853 list_for_each_entry_rcu(srp, &skp->smk_rules, list) {
1854 okp = srp->smk_object;
1855 /*
1856 * Matching labels always allows access.
1857 */
1858 if (mkp->smk_known == okp->smk_known)
1859 continue;
1860 /*
1861 * If there is a matching local rule take
1862 * that into account as well.
1863 */
1864 may = smk_access_entry(srp->smk_subject->smk_known,
1865 okp->smk_known,
1866 &tsp->smk_rules);
1867 if (may == -ENOENT)
1868 may = srp->smk_access;
1869 else
1870 may &= srp->smk_access;
1871 /*
1872 * If may is zero the SMACK64MMAP subject can't
1873 * possibly have less access.
1874 */
1875 if (may == 0)
1876 continue;
1877
1878 /*
1879 * Fetch the global list entry.
1880 * If there isn't one a SMACK64MMAP subject
1881 * can't have as much access as current.
1882 */
1883 mmay = smk_access_entry(mkp->smk_known, okp->smk_known,
1884 &mkp->smk_rules);
1885 if (mmay == -ENOENT) {
1886 rc = -EACCES;
1887 break;
1888 }
1889 /*
1890 * If there is a local entry it modifies the
1891 * potential access, too.
1892 */
1893 tmay = smk_access_entry(mkp->smk_known, okp->smk_known,
1894 &tsp->smk_rules);
1895 if (tmay != -ENOENT)
1896 mmay &= tmay;
1897
1898 /*
1899 * If there is any access available to current that is
1900 * not available to a SMACK64MMAP subject
1901 * deny access.
1902 */
1903 if ((may | mmay) != mmay) {
1904 rc = -EACCES;
1905 break;
1906 }
1907 }
1908
1909 rcu_read_unlock();
1910
1911 return rc;
1912}
1913
1914/**
1915 * smack_file_set_fowner - set the file security blob value
1916 * @file: object in question
1917 *
1918 */
1919static void smack_file_set_fowner(struct file *file)
1920{
1921 struct smack_known **blob = smack_file(file);
1922
1923 *blob = smk_of_current();
1924}
1925
1926/**
1927 * smack_file_send_sigiotask - Smack on sigio
1928 * @tsk: The target task
1929 * @fown: the object the signal come from
1930 * @signum: unused
1931 *
1932 * Allow a privileged task to get signals even if it shouldn't
1933 *
1934 * Returns 0 if a subject with the object's smack could
1935 * write to the task, an error code otherwise.
1936 */
1937static int smack_file_send_sigiotask(struct task_struct *tsk,
1938 struct fown_struct *fown, int signum)
1939{
1940 struct smack_known **blob;
1941 struct smack_known *skp;
1942 struct smack_known *tkp = smk_of_task(smack_cred(tsk->cred));
1943 const struct cred *tcred;
1944 struct file *file;
1945 int rc;
1946 struct smk_audit_info ad;
1947
1948 /*
1949 * struct fown_struct is never outside the context of a struct file
1950 */
1951 file = fown->file;
1952
1953 /* we don't log here as rc can be overriden */
1954 blob = smack_file(file);
1955 skp = *blob;
1956 rc = smk_access(skp, tkp, MAY_DELIVER, NULL);
1957 rc = smk_bu_note("sigiotask", skp, tkp, MAY_DELIVER, rc);
1958
1959 rcu_read_lock();
1960 tcred = __task_cred(tsk);
1961 if (rc != 0 && smack_privileged_cred(CAP_MAC_OVERRIDE, tcred))
1962 rc = 0;
1963 rcu_read_unlock();
1964
1965 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1966 smk_ad_setfield_u_tsk(&ad, tsk);
1967 smack_log(skp->smk_known, tkp->smk_known, MAY_DELIVER, rc, &ad);
1968 return rc;
1969}
1970
1971/**
1972 * smack_file_receive - Smack file receive check
1973 * @file: the object
1974 *
1975 * Returns 0 if current has access, error code otherwise
1976 */
1977static int smack_file_receive(struct file *file)
1978{
1979 int rc;
1980 int may = 0;
1981 struct smk_audit_info ad;
1982 struct inode *inode = file_inode(file);
1983 struct socket *sock;
1984 struct task_smack *tsp;
1985 struct socket_smack *ssp;
1986
1987 if (unlikely(IS_PRIVATE(inode)))
1988 return 0;
1989
1990 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1991 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1992
1993 if (inode->i_sb->s_magic == SOCKFS_MAGIC) {
1994 sock = SOCKET_I(inode);
1995 ssp = smack_sock(sock->sk);
1996 tsp = smack_cred(current_cred());
1997 /*
1998 * If the receiving process can't write to the
1999 * passed socket or if the passed socket can't
2000 * write to the receiving process don't accept
2001 * the passed socket.
2002 */
2003 rc = smk_access(tsp->smk_task, ssp->smk_out, MAY_WRITE, &ad);
2004 rc = smk_bu_file(file, may, rc);
2005 if (rc < 0)
2006 return rc;
2007 rc = smk_access(ssp->smk_in, tsp->smk_task, MAY_WRITE, &ad);
2008 rc = smk_bu_file(file, may, rc);
2009 return rc;
2010 }
2011 /*
2012 * This code relies on bitmasks.
2013 */
2014 if (file->f_mode & FMODE_READ)
2015 may = MAY_READ;
2016 if (file->f_mode & FMODE_WRITE)
2017 may |= MAY_WRITE;
2018
2019 rc = smk_curacc(smk_of_inode(inode), may, &ad);
2020 rc = smk_bu_file(file, may, rc);
2021 return rc;
2022}
2023
2024/**
2025 * smack_file_open - Smack dentry open processing
2026 * @file: the object
2027 *
2028 * Set the security blob in the file structure.
2029 * Allow the open only if the task has read access. There are
2030 * many read operations (e.g. fstat) that you can do with an
2031 * fd even if you have the file open write-only.
2032 *
2033 * Returns 0 if current has access, error code otherwise
2034 */
2035static int smack_file_open(struct file *file)
2036{
2037 struct task_smack *tsp = smack_cred(file->f_cred);
2038 struct inode *inode = file_inode(file);
2039 struct smk_audit_info ad;
2040 int rc;
2041
2042 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
2043 smk_ad_setfield_u_fs_path(&ad, file->f_path);
2044 rc = smk_tskacc(tsp, smk_of_inode(inode), MAY_READ, &ad);
2045 rc = smk_bu_credfile(file->f_cred, file, MAY_READ, rc);
2046
2047 return rc;
2048}
2049
2050/*
2051 * Task hooks
2052 */
2053
2054/**
2055 * smack_cred_alloc_blank - "allocate" blank task-level security credentials
2056 * @cred: the new credentials
2057 * @gfp: the atomicity of any memory allocations
2058 *
2059 * Prepare a blank set of credentials for modification. This must allocate all
2060 * the memory the LSM module might require such that cred_transfer() can
2061 * complete without error.
2062 */
2063static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp)
2064{
2065 init_task_smack(smack_cred(cred), NULL, NULL);
2066 return 0;
2067}
2068
2069
2070/**
2071 * smack_cred_free - "free" task-level security credentials
2072 * @cred: the credentials in question
2073 *
2074 */
2075static void smack_cred_free(struct cred *cred)
2076{
2077 struct task_smack *tsp = smack_cred(cred);
2078 struct smack_rule *rp;
2079 struct list_head *l;
2080 struct list_head *n;
2081
2082 smk_destroy_label_list(&tsp->smk_relabel);
2083
2084 list_for_each_safe(l, n, &tsp->smk_rules) {
2085 rp = list_entry(l, struct smack_rule, list);
2086 list_del(&rp->list);
2087 kmem_cache_free(smack_rule_cache, rp);
2088 }
2089}
2090
2091/**
2092 * smack_cred_prepare - prepare new set of credentials for modification
2093 * @new: the new credentials
2094 * @old: the original credentials
2095 * @gfp: the atomicity of any memory allocations
2096 *
2097 * Prepare a new set of credentials for modification.
2098 */
2099static int smack_cred_prepare(struct cred *new, const struct cred *old,
2100 gfp_t gfp)
2101{
2102 struct task_smack *old_tsp = smack_cred(old);
2103 struct task_smack *new_tsp = smack_cred(new);
2104 int rc;
2105
2106 init_task_smack(new_tsp, old_tsp->smk_task, old_tsp->smk_task);
2107
2108 rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp);
2109 if (rc != 0)
2110 return rc;
2111
2112 rc = smk_copy_relabel(&new_tsp->smk_relabel, &old_tsp->smk_relabel,
2113 gfp);
2114 return rc;
2115}
2116
2117/**
2118 * smack_cred_transfer - Transfer the old credentials to the new credentials
2119 * @new: the new credentials
2120 * @old: the original credentials
2121 *
2122 * Fill in a set of blank credentials from another set of credentials.
2123 */
2124static void smack_cred_transfer(struct cred *new, const struct cred *old)
2125{
2126 struct task_smack *old_tsp = smack_cred(old);
2127 struct task_smack *new_tsp = smack_cred(new);
2128
2129 init_task_smack(new_tsp, old_tsp->smk_task, old_tsp->smk_task);
2130}
2131
2132/**
2133 * smack_cred_getsecid - get the secid corresponding to a creds structure
2134 * @cred: the object creds
2135 * @secid: where to put the result
2136 *
2137 * Sets the secid to contain a u32 version of the smack label.
2138 */
2139static void smack_cred_getsecid(const struct cred *cred, u32 *secid)
2140{
2141 struct smack_known *skp;
2142
2143 rcu_read_lock();
2144 skp = smk_of_task(smack_cred(cred));
2145 *secid = skp->smk_secid;
2146 rcu_read_unlock();
2147}
2148
2149/**
2150 * smack_cred_getlsmprop - get the Smack label for a creds structure
2151 * @cred: the object creds
2152 * @prop: where to put the data
2153 *
2154 * Sets the Smack part of the ref
2155 */
2156static void smack_cred_getlsmprop(const struct cred *cred,
2157 struct lsm_prop *prop)
2158{
2159 rcu_read_lock();
2160 prop->smack.skp = smk_of_task(smack_cred(cred));
2161 rcu_read_unlock();
2162}
2163
2164/**
2165 * smack_kernel_act_as - Set the subjective context in a set of credentials
2166 * @new: points to the set of credentials to be modified.
2167 * @secid: specifies the security ID to be set
2168 *
2169 * Set the security data for a kernel service.
2170 */
2171static int smack_kernel_act_as(struct cred *new, u32 secid)
2172{
2173 struct task_smack *new_tsp = smack_cred(new);
2174
2175 new_tsp->smk_task = smack_from_secid(secid);
2176 return 0;
2177}
2178
2179/**
2180 * smack_kernel_create_files_as - Set the file creation label in a set of creds
2181 * @new: points to the set of credentials to be modified
2182 * @inode: points to the inode to use as a reference
2183 *
2184 * Set the file creation context in a set of credentials to the same
2185 * as the objective context of the specified inode
2186 */
2187static int smack_kernel_create_files_as(struct cred *new,
2188 struct inode *inode)
2189{
2190 struct inode_smack *isp = smack_inode(inode);
2191 struct task_smack *tsp = smack_cred(new);
2192
2193 tsp->smk_forked = isp->smk_inode;
2194 tsp->smk_task = tsp->smk_forked;
2195 return 0;
2196}
2197
2198/**
2199 * smk_curacc_on_task - helper to log task related access
2200 * @p: the task object
2201 * @access: the access requested
2202 * @caller: name of the calling function for audit
2203 *
2204 * Return 0 if access is permitted
2205 */
2206static int smk_curacc_on_task(struct task_struct *p, int access,
2207 const char *caller)
2208{
2209 struct smk_audit_info ad;
2210 struct smack_known *skp = smk_of_task_struct_obj(p);
2211 int rc;
2212
2213 smk_ad_init(&ad, caller, LSM_AUDIT_DATA_TASK);
2214 smk_ad_setfield_u_tsk(&ad, p);
2215 rc = smk_curacc(skp, access, &ad);
2216 rc = smk_bu_task(p, access, rc);
2217 return rc;
2218}
2219
2220/**
2221 * smack_task_setpgid - Smack check on setting pgid
2222 * @p: the task object
2223 * @pgid: unused
2224 *
2225 * Return 0 if write access is permitted
2226 */
2227static int smack_task_setpgid(struct task_struct *p, pid_t pgid)
2228{
2229 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2230}
2231
2232/**
2233 * smack_task_getpgid - Smack access check for getpgid
2234 * @p: the object task
2235 *
2236 * Returns 0 if current can read the object task, error code otherwise
2237 */
2238static int smack_task_getpgid(struct task_struct *p)
2239{
2240 return smk_curacc_on_task(p, MAY_READ, __func__);
2241}
2242
2243/**
2244 * smack_task_getsid - Smack access check for getsid
2245 * @p: the object task
2246 *
2247 * Returns 0 if current can read the object task, error code otherwise
2248 */
2249static int smack_task_getsid(struct task_struct *p)
2250{
2251 return smk_curacc_on_task(p, MAY_READ, __func__);
2252}
2253
2254/**
2255 * smack_current_getlsmprop_subj - get the subjective secid of the current task
2256 * @prop: where to put the result
2257 *
2258 * Sets the secid to contain a u32 version of the task's subjective smack label.
2259 */
2260static void smack_current_getlsmprop_subj(struct lsm_prop *prop)
2261{
2262 prop->smack.skp = smk_of_current();
2263}
2264
2265/**
2266 * smack_task_getlsmprop_obj - get the objective data of the task
2267 * @p: the task
2268 * @prop: where to put the result
2269 *
2270 * Sets the secid to contain a u32 version of the task's objective smack label.
2271 */
2272static void smack_task_getlsmprop_obj(struct task_struct *p,
2273 struct lsm_prop *prop)
2274{
2275 prop->smack.skp = smk_of_task_struct_obj(p);
2276}
2277
2278/**
2279 * smack_task_setnice - Smack check on setting nice
2280 * @p: the task object
2281 * @nice: unused
2282 *
2283 * Return 0 if write access is permitted
2284 */
2285static int smack_task_setnice(struct task_struct *p, int nice)
2286{
2287 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2288}
2289
2290/**
2291 * smack_task_setioprio - Smack check on setting ioprio
2292 * @p: the task object
2293 * @ioprio: unused
2294 *
2295 * Return 0 if write access is permitted
2296 */
2297static int smack_task_setioprio(struct task_struct *p, int ioprio)
2298{
2299 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2300}
2301
2302/**
2303 * smack_task_getioprio - Smack check on reading ioprio
2304 * @p: the task object
2305 *
2306 * Return 0 if read access is permitted
2307 */
2308static int smack_task_getioprio(struct task_struct *p)
2309{
2310 return smk_curacc_on_task(p, MAY_READ, __func__);
2311}
2312
2313/**
2314 * smack_task_setscheduler - Smack check on setting scheduler
2315 * @p: the task object
2316 *
2317 * Return 0 if read access is permitted
2318 */
2319static int smack_task_setscheduler(struct task_struct *p)
2320{
2321 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2322}
2323
2324/**
2325 * smack_task_getscheduler - Smack check on reading scheduler
2326 * @p: the task object
2327 *
2328 * Return 0 if read access is permitted
2329 */
2330static int smack_task_getscheduler(struct task_struct *p)
2331{
2332 return smk_curacc_on_task(p, MAY_READ, __func__);
2333}
2334
2335/**
2336 * smack_task_movememory - Smack check on moving memory
2337 * @p: the task object
2338 *
2339 * Return 0 if write access is permitted
2340 */
2341static int smack_task_movememory(struct task_struct *p)
2342{
2343 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2344}
2345
2346/**
2347 * smack_task_kill - Smack check on signal delivery
2348 * @p: the task object
2349 * @info: unused
2350 * @sig: unused
2351 * @cred: identifies the cred to use in lieu of current's
2352 *
2353 * Return 0 if write access is permitted
2354 *
2355 */
2356static int smack_task_kill(struct task_struct *p, struct kernel_siginfo *info,
2357 int sig, const struct cred *cred)
2358{
2359 struct smk_audit_info ad;
2360 struct smack_known *skp;
2361 struct smack_known *tkp = smk_of_task_struct_obj(p);
2362 int rc;
2363
2364 if (!sig)
2365 return 0; /* null signal; existence test */
2366
2367 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
2368 smk_ad_setfield_u_tsk(&ad, p);
2369 /*
2370 * Sending a signal requires that the sender
2371 * can write the receiver.
2372 */
2373 if (cred == NULL) {
2374 rc = smk_curacc(tkp, MAY_DELIVER, &ad);
2375 rc = smk_bu_task(p, MAY_DELIVER, rc);
2376 return rc;
2377 }
2378 /*
2379 * If the cred isn't NULL we're dealing with some USB IO
2380 * specific behavior. This is not clean. For one thing
2381 * we can't take privilege into account.
2382 */
2383 skp = smk_of_task(smack_cred(cred));
2384 rc = smk_access(skp, tkp, MAY_DELIVER, &ad);
2385 rc = smk_bu_note("USB signal", skp, tkp, MAY_DELIVER, rc);
2386 return rc;
2387}
2388
2389/**
2390 * smack_task_to_inode - copy task smack into the inode blob
2391 * @p: task to copy from
2392 * @inode: inode to copy to
2393 *
2394 * Sets the smack pointer in the inode security blob
2395 */
2396static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
2397{
2398 struct inode_smack *isp = smack_inode(inode);
2399 struct smack_known *skp = smk_of_task_struct_obj(p);
2400
2401 isp->smk_inode = skp;
2402 isp->smk_flags |= SMK_INODE_INSTANT;
2403}
2404
2405/*
2406 * Socket hooks.
2407 */
2408
2409/**
2410 * smack_sk_alloc_security - Allocate a socket blob
2411 * @sk: the socket
2412 * @family: unused
2413 * @gfp_flags: memory allocation flags
2414 *
2415 * Assign Smack pointers to current
2416 *
2417 * Returns 0 on success, -ENOMEM is there's no memory
2418 */
2419static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags)
2420{
2421 struct smack_known *skp = smk_of_current();
2422 struct socket_smack *ssp = smack_sock(sk);
2423
2424 /*
2425 * Sockets created by kernel threads receive web label.
2426 */
2427 if (unlikely(current->flags & PF_KTHREAD)) {
2428 ssp->smk_in = &smack_known_web;
2429 ssp->smk_out = &smack_known_web;
2430 } else {
2431 ssp->smk_in = skp;
2432 ssp->smk_out = skp;
2433 }
2434 ssp->smk_packet = NULL;
2435
2436 return 0;
2437}
2438
2439#ifdef SMACK_IPV6_PORT_LABELING
2440/**
2441 * smack_sk_free_security - Free a socket blob
2442 * @sk: the socket
2443 *
2444 * Clears the blob pointer
2445 */
2446static void smack_sk_free_security(struct sock *sk)
2447{
2448 struct smk_port_label *spp;
2449
2450 if (sk->sk_family == PF_INET6) {
2451 rcu_read_lock();
2452 list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
2453 if (spp->smk_sock != sk)
2454 continue;
2455 spp->smk_can_reuse = 1;
2456 break;
2457 }
2458 rcu_read_unlock();
2459 }
2460}
2461#endif
2462
2463/**
2464 * smack_sk_clone_security - Copy security context
2465 * @sk: the old socket
2466 * @newsk: the new socket
2467 *
2468 * Copy the security context of the old socket pointer to the cloned
2469 */
2470static void smack_sk_clone_security(const struct sock *sk, struct sock *newsk)
2471{
2472 struct socket_smack *ssp_old = smack_sock(sk);
2473 struct socket_smack *ssp_new = smack_sock(newsk);
2474
2475 *ssp_new = *ssp_old;
2476}
2477
2478/**
2479* smack_ipv4host_label - check host based restrictions
2480* @sip: the object end
2481*
2482* looks for host based access restrictions
2483*
2484* This version will only be appropriate for really small sets of single label
2485* hosts. The caller is responsible for ensuring that the RCU read lock is
2486* taken before calling this function.
2487*
2488* Returns the label of the far end or NULL if it's not special.
2489*/
2490static struct smack_known *smack_ipv4host_label(struct sockaddr_in *sip)
2491{
2492 struct smk_net4addr *snp;
2493 struct in_addr *siap = &sip->sin_addr;
2494
2495 if (siap->s_addr == 0)
2496 return NULL;
2497
2498 list_for_each_entry_rcu(snp, &smk_net4addr_list, list)
2499 /*
2500 * we break after finding the first match because
2501 * the list is sorted from longest to shortest mask
2502 * so we have found the most specific match
2503 */
2504 if (snp->smk_host.s_addr ==
2505 (siap->s_addr & snp->smk_mask.s_addr))
2506 return snp->smk_label;
2507
2508 return NULL;
2509}
2510
2511/*
2512 * smk_ipv6_localhost - Check for local ipv6 host address
2513 * @sip: the address
2514 *
2515 * Returns boolean true if this is the localhost address
2516 */
2517static bool smk_ipv6_localhost(struct sockaddr_in6 *sip)
2518{
2519 __be16 *be16p = (__be16 *)&sip->sin6_addr;
2520 __be32 *be32p = (__be32 *)&sip->sin6_addr;
2521
2522 if (be32p[0] == 0 && be32p[1] == 0 && be32p[2] == 0 && be16p[6] == 0 &&
2523 ntohs(be16p[7]) == 1)
2524 return true;
2525 return false;
2526}
2527
2528/**
2529* smack_ipv6host_label - check host based restrictions
2530* @sip: the object end
2531*
2532* looks for host based access restrictions
2533*
2534* This version will only be appropriate for really small sets of single label
2535* hosts. The caller is responsible for ensuring that the RCU read lock is
2536* taken before calling this function.
2537*
2538* Returns the label of the far end or NULL if it's not special.
2539*/
2540static struct smack_known *smack_ipv6host_label(struct sockaddr_in6 *sip)
2541{
2542 struct smk_net6addr *snp;
2543 struct in6_addr *sap = &sip->sin6_addr;
2544 int i;
2545 int found = 0;
2546
2547 /*
2548 * It's local. Don't look for a host label.
2549 */
2550 if (smk_ipv6_localhost(sip))
2551 return NULL;
2552
2553 list_for_each_entry_rcu(snp, &smk_net6addr_list, list) {
2554 /*
2555 * If the label is NULL the entry has
2556 * been renounced. Ignore it.
2557 */
2558 if (snp->smk_label == NULL)
2559 continue;
2560 /*
2561 * we break after finding the first match because
2562 * the list is sorted from longest to shortest mask
2563 * so we have found the most specific match
2564 */
2565 for (found = 1, i = 0; i < 8; i++) {
2566 if ((sap->s6_addr16[i] & snp->smk_mask.s6_addr16[i]) !=
2567 snp->smk_host.s6_addr16[i]) {
2568 found = 0;
2569 break;
2570 }
2571 }
2572 if (found)
2573 return snp->smk_label;
2574 }
2575
2576 return NULL;
2577}
2578
2579/**
2580 * smack_netlbl_add - Set the secattr on a socket
2581 * @sk: the socket
2582 *
2583 * Attach the outbound smack value (smk_out) to the socket.
2584 *
2585 * Returns 0 on success or an error code
2586 */
2587static int smack_netlbl_add(struct sock *sk)
2588{
2589 struct socket_smack *ssp = smack_sock(sk);
2590 struct smack_known *skp = ssp->smk_out;
2591 int rc;
2592
2593 local_bh_disable();
2594 bh_lock_sock_nested(sk);
2595
2596 rc = netlbl_sock_setattr(sk, sk->sk_family, &skp->smk_netlabel,
2597 netlbl_sk_lock_check(sk));
2598 switch (rc) {
2599 case 0:
2600 ssp->smk_state = SMK_NETLBL_LABELED;
2601 break;
2602 case -EDESTADDRREQ:
2603 ssp->smk_state = SMK_NETLBL_REQSKB;
2604 rc = 0;
2605 break;
2606 }
2607
2608 bh_unlock_sock(sk);
2609 local_bh_enable();
2610
2611 return rc;
2612}
2613
2614/**
2615 * smack_netlbl_delete - Remove the secattr from a socket
2616 * @sk: the socket
2617 *
2618 * Remove the outbound smack value from a socket
2619 */
2620static void smack_netlbl_delete(struct sock *sk)
2621{
2622 struct socket_smack *ssp = smack_sock(sk);
2623
2624 /*
2625 * Take the label off the socket if one is set.
2626 */
2627 if (ssp->smk_state != SMK_NETLBL_LABELED)
2628 return;
2629
2630 local_bh_disable();
2631 bh_lock_sock_nested(sk);
2632 netlbl_sock_delattr(sk);
2633 bh_unlock_sock(sk);
2634 local_bh_enable();
2635 ssp->smk_state = SMK_NETLBL_UNLABELED;
2636}
2637
2638/**
2639 * smk_ipv4_check - Perform IPv4 host access checks
2640 * @sk: the socket
2641 * @sap: the destination address
2642 *
2643 * Set the correct secattr for the given socket based on the destination
2644 * address and perform any outbound access checks needed.
2645 *
2646 * Returns 0 on success or an error code.
2647 *
2648 */
2649static int smk_ipv4_check(struct sock *sk, struct sockaddr_in *sap)
2650{
2651 struct smack_known *skp;
2652 int rc = 0;
2653 struct smack_known *hkp;
2654 struct socket_smack *ssp = smack_sock(sk);
2655 struct smk_audit_info ad;
2656
2657 rcu_read_lock();
2658 hkp = smack_ipv4host_label(sap);
2659 if (hkp != NULL) {
2660#ifdef CONFIG_AUDIT
2661 struct lsm_network_audit net;
2662
2663 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
2664 ad.a.u.net->family = sap->sin_family;
2665 ad.a.u.net->dport = sap->sin_port;
2666 ad.a.u.net->v4info.daddr = sap->sin_addr.s_addr;
2667#endif
2668 skp = ssp->smk_out;
2669 rc = smk_access(skp, hkp, MAY_WRITE, &ad);
2670 rc = smk_bu_note("IPv4 host check", skp, hkp, MAY_WRITE, rc);
2671 /*
2672 * Clear the socket netlabel if it's set.
2673 */
2674 if (!rc)
2675 smack_netlbl_delete(sk);
2676 }
2677 rcu_read_unlock();
2678
2679 return rc;
2680}
2681
2682/**
2683 * smk_ipv6_check - check Smack access
2684 * @subject: subject Smack label
2685 * @object: object Smack label
2686 * @address: address
2687 * @act: the action being taken
2688 *
2689 * Check an IPv6 access
2690 */
2691static int smk_ipv6_check(struct smack_known *subject,
2692 struct smack_known *object,
2693 struct sockaddr_in6 *address, int act)
2694{
2695#ifdef CONFIG_AUDIT
2696 struct lsm_network_audit net;
2697#endif
2698 struct smk_audit_info ad;
2699 int rc;
2700
2701#ifdef CONFIG_AUDIT
2702 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
2703 ad.a.u.net->family = PF_INET6;
2704 ad.a.u.net->dport = address->sin6_port;
2705 if (act == SMK_RECEIVING)
2706 ad.a.u.net->v6info.saddr = address->sin6_addr;
2707 else
2708 ad.a.u.net->v6info.daddr = address->sin6_addr;
2709#endif
2710 rc = smk_access(subject, object, MAY_WRITE, &ad);
2711 rc = smk_bu_note("IPv6 check", subject, object, MAY_WRITE, rc);
2712 return rc;
2713}
2714
2715#ifdef SMACK_IPV6_PORT_LABELING
2716/**
2717 * smk_ipv6_port_label - Smack port access table management
2718 * @sock: socket
2719 * @address: address
2720 *
2721 * Create or update the port list entry
2722 */
2723static void smk_ipv6_port_label(struct socket *sock, struct sockaddr *address)
2724{
2725 struct sock *sk = sock->sk;
2726 struct sockaddr_in6 *addr6;
2727 struct socket_smack *ssp = smack_sock(sock->sk);
2728 struct smk_port_label *spp;
2729 unsigned short port = 0;
2730
2731 if (address == NULL) {
2732 /*
2733 * This operation is changing the Smack information
2734 * on the bound socket. Take the changes to the port
2735 * as well.
2736 */
2737 rcu_read_lock();
2738 list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
2739 if (sk != spp->smk_sock)
2740 continue;
2741 spp->smk_in = ssp->smk_in;
2742 spp->smk_out = ssp->smk_out;
2743 rcu_read_unlock();
2744 return;
2745 }
2746 /*
2747 * A NULL address is only used for updating existing
2748 * bound entries. If there isn't one, it's OK.
2749 */
2750 rcu_read_unlock();
2751 return;
2752 }
2753
2754 addr6 = (struct sockaddr_in6 *)address;
2755 port = ntohs(addr6->sin6_port);
2756 /*
2757 * This is a special case that is safely ignored.
2758 */
2759 if (port == 0)
2760 return;
2761
2762 /*
2763 * Look for an existing port list entry.
2764 * This is an indication that a port is getting reused.
2765 */
2766 rcu_read_lock();
2767 list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
2768 if (spp->smk_port != port || spp->smk_sock_type != sock->type)
2769 continue;
2770 if (spp->smk_can_reuse != 1) {
2771 rcu_read_unlock();
2772 return;
2773 }
2774 spp->smk_port = port;
2775 spp->smk_sock = sk;
2776 spp->smk_in = ssp->smk_in;
2777 spp->smk_out = ssp->smk_out;
2778 spp->smk_can_reuse = 0;
2779 rcu_read_unlock();
2780 return;
2781 }
2782 rcu_read_unlock();
2783 /*
2784 * A new port entry is required.
2785 */
2786 spp = kzalloc(sizeof(*spp), GFP_KERNEL);
2787 if (spp == NULL)
2788 return;
2789
2790 spp->smk_port = port;
2791 spp->smk_sock = sk;
2792 spp->smk_in = ssp->smk_in;
2793 spp->smk_out = ssp->smk_out;
2794 spp->smk_sock_type = sock->type;
2795 spp->smk_can_reuse = 0;
2796
2797 mutex_lock(&smack_ipv6_lock);
2798 list_add_rcu(&spp->list, &smk_ipv6_port_list);
2799 mutex_unlock(&smack_ipv6_lock);
2800 return;
2801}
2802
2803/**
2804 * smk_ipv6_port_check - check Smack port access
2805 * @sk: socket
2806 * @address: address
2807 * @act: the action being taken
2808 *
2809 * Create or update the port list entry
2810 */
2811static int smk_ipv6_port_check(struct sock *sk, struct sockaddr_in6 *address,
2812 int act)
2813{
2814 struct smk_port_label *spp;
2815 struct socket_smack *ssp = smack_sock(sk);
2816 struct smack_known *skp = NULL;
2817 unsigned short port;
2818 struct smack_known *object;
2819
2820 if (act == SMK_RECEIVING) {
2821 skp = smack_ipv6host_label(address);
2822 object = ssp->smk_in;
2823 } else {
2824 skp = ssp->smk_out;
2825 object = smack_ipv6host_label(address);
2826 }
2827
2828 /*
2829 * The other end is a single label host.
2830 */
2831 if (skp != NULL && object != NULL)
2832 return smk_ipv6_check(skp, object, address, act);
2833 if (skp == NULL)
2834 skp = smack_net_ambient;
2835 if (object == NULL)
2836 object = smack_net_ambient;
2837
2838 /*
2839 * It's remote, so port lookup does no good.
2840 */
2841 if (!smk_ipv6_localhost(address))
2842 return smk_ipv6_check(skp, object, address, act);
2843
2844 /*
2845 * It's local so the send check has to have passed.
2846 */
2847 if (act == SMK_RECEIVING)
2848 return 0;
2849
2850 port = ntohs(address->sin6_port);
2851 rcu_read_lock();
2852 list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
2853 if (spp->smk_port != port || spp->smk_sock_type != sk->sk_type)
2854 continue;
2855 object = spp->smk_in;
2856 if (act == SMK_CONNECTING)
2857 ssp->smk_packet = spp->smk_out;
2858 break;
2859 }
2860 rcu_read_unlock();
2861
2862 return smk_ipv6_check(skp, object, address, act);
2863}
2864#endif
2865
2866/**
2867 * smack_inode_setsecurity - set smack xattrs
2868 * @inode: the object
2869 * @name: attribute name
2870 * @value: attribute value
2871 * @size: size of the attribute
2872 * @flags: unused
2873 *
2874 * Sets the named attribute in the appropriate blob
2875 *
2876 * Returns 0 on success, or an error code
2877 */
2878static int smack_inode_setsecurity(struct inode *inode, const char *name,
2879 const void *value, size_t size, int flags)
2880{
2881 struct smack_known *skp;
2882 struct inode_smack *nsp = smack_inode(inode);
2883 struct socket_smack *ssp;
2884 struct socket *sock;
2885 int rc = 0;
2886
2887 if (value == NULL || size > SMK_LONGLABEL || size == 0)
2888 return -EINVAL;
2889
2890 if (strcmp(name, XATTR_SMACK_TRANSMUTE) == 0) {
2891 if (!S_ISDIR(inode->i_mode) || size != TRANS_TRUE_SIZE ||
2892 strncmp(value, TRANS_TRUE, TRANS_TRUE_SIZE) != 0)
2893 return -EINVAL;
2894
2895 nsp->smk_flags |= SMK_INODE_TRANSMUTE;
2896 return 0;
2897 }
2898
2899 skp = smk_import_entry(value, size);
2900 if (IS_ERR(skp))
2901 return PTR_ERR(skp);
2902
2903 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
2904 nsp->smk_inode = skp;
2905 nsp->smk_flags |= SMK_INODE_INSTANT;
2906 return 0;
2907 }
2908 /*
2909 * The rest of the Smack xattrs are only on sockets.
2910 */
2911 if (inode->i_sb->s_magic != SOCKFS_MAGIC)
2912 return -EOPNOTSUPP;
2913
2914 sock = SOCKET_I(inode);
2915 if (sock == NULL || sock->sk == NULL)
2916 return -EOPNOTSUPP;
2917
2918 ssp = smack_sock(sock->sk);
2919
2920 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
2921 ssp->smk_in = skp;
2922 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) {
2923 ssp->smk_out = skp;
2924 if (sock->sk->sk_family == PF_INET) {
2925 rc = smack_netlbl_add(sock->sk);
2926 if (rc != 0)
2927 printk(KERN_WARNING
2928 "Smack: \"%s\" netlbl error %d.\n",
2929 __func__, -rc);
2930 }
2931 } else
2932 return -EOPNOTSUPP;
2933
2934#ifdef SMACK_IPV6_PORT_LABELING
2935 if (sock->sk->sk_family == PF_INET6)
2936 smk_ipv6_port_label(sock, NULL);
2937#endif
2938
2939 return 0;
2940}
2941
2942/**
2943 * smack_socket_post_create - finish socket setup
2944 * @sock: the socket
2945 * @family: protocol family
2946 * @type: unused
2947 * @protocol: unused
2948 * @kern: unused
2949 *
2950 * Sets the netlabel information on the socket
2951 *
2952 * Returns 0 on success, and error code otherwise
2953 */
2954static int smack_socket_post_create(struct socket *sock, int family,
2955 int type, int protocol, int kern)
2956{
2957 struct socket_smack *ssp;
2958
2959 if (sock->sk == NULL)
2960 return 0;
2961
2962 /*
2963 * Sockets created by kernel threads receive web label.
2964 */
2965 if (unlikely(current->flags & PF_KTHREAD)) {
2966 ssp = smack_sock(sock->sk);
2967 ssp->smk_in = &smack_known_web;
2968 ssp->smk_out = &smack_known_web;
2969 }
2970
2971 if (family != PF_INET)
2972 return 0;
2973 /*
2974 * Set the outbound netlbl.
2975 */
2976 return smack_netlbl_add(sock->sk);
2977}
2978
2979/**
2980 * smack_socket_socketpair - create socket pair
2981 * @socka: one socket
2982 * @sockb: another socket
2983 *
2984 * Cross reference the peer labels for SO_PEERSEC
2985 *
2986 * Returns 0
2987 */
2988static int smack_socket_socketpair(struct socket *socka,
2989 struct socket *sockb)
2990{
2991 struct socket_smack *asp = smack_sock(socka->sk);
2992 struct socket_smack *bsp = smack_sock(sockb->sk);
2993
2994 asp->smk_packet = bsp->smk_out;
2995 bsp->smk_packet = asp->smk_out;
2996
2997 return 0;
2998}
2999
3000#ifdef SMACK_IPV6_PORT_LABELING
3001/**
3002 * smack_socket_bind - record port binding information.
3003 * @sock: the socket
3004 * @address: the port address
3005 * @addrlen: size of the address
3006 *
3007 * Records the label bound to a port.
3008 *
3009 * Returns 0 on success, and error code otherwise
3010 */
3011static int smack_socket_bind(struct socket *sock, struct sockaddr *address,
3012 int addrlen)
3013{
3014 if (sock->sk != NULL && sock->sk->sk_family == PF_INET6) {
3015 if (addrlen < SIN6_LEN_RFC2133 ||
3016 address->sa_family != AF_INET6)
3017 return -EINVAL;
3018 smk_ipv6_port_label(sock, address);
3019 }
3020 return 0;
3021}
3022#endif /* SMACK_IPV6_PORT_LABELING */
3023
3024/**
3025 * smack_socket_connect - connect access check
3026 * @sock: the socket
3027 * @sap: the other end
3028 * @addrlen: size of sap
3029 *
3030 * Verifies that a connection may be possible
3031 *
3032 * Returns 0 on success, and error code otherwise
3033 */
3034static int smack_socket_connect(struct socket *sock, struct sockaddr *sap,
3035 int addrlen)
3036{
3037 int rc = 0;
3038
3039 if (sock->sk == NULL)
3040 return 0;
3041 if (sock->sk->sk_family != PF_INET &&
3042 (!IS_ENABLED(CONFIG_IPV6) || sock->sk->sk_family != PF_INET6))
3043 return 0;
3044 if (addrlen < offsetofend(struct sockaddr, sa_family))
3045 return 0;
3046 if (IS_ENABLED(CONFIG_IPV6) && sap->sa_family == AF_INET6) {
3047 struct sockaddr_in6 *sip = (struct sockaddr_in6 *)sap;
3048 struct smack_known *rsp = NULL;
3049
3050 if (addrlen < SIN6_LEN_RFC2133)
3051 return 0;
3052 if (__is_defined(SMACK_IPV6_SECMARK_LABELING))
3053 rsp = smack_ipv6host_label(sip);
3054 if (rsp != NULL) {
3055 struct socket_smack *ssp = smack_sock(sock->sk);
3056
3057 rc = smk_ipv6_check(ssp->smk_out, rsp, sip,
3058 SMK_CONNECTING);
3059 }
3060#ifdef SMACK_IPV6_PORT_LABELING
3061 rc = smk_ipv6_port_check(sock->sk, sip, SMK_CONNECTING);
3062#endif
3063
3064 return rc;
3065 }
3066 if (sap->sa_family != AF_INET || addrlen < sizeof(struct sockaddr_in))
3067 return 0;
3068 rc = smk_ipv4_check(sock->sk, (struct sockaddr_in *)sap);
3069 return rc;
3070}
3071
3072/**
3073 * smack_flags_to_may - convert S_ to MAY_ values
3074 * @flags: the S_ value
3075 *
3076 * Returns the equivalent MAY_ value
3077 */
3078static int smack_flags_to_may(int flags)
3079{
3080 int may = 0;
3081
3082 if (flags & S_IRUGO)
3083 may |= MAY_READ;
3084 if (flags & S_IWUGO)
3085 may |= MAY_WRITE;
3086 if (flags & S_IXUGO)
3087 may |= MAY_EXEC;
3088
3089 return may;
3090}
3091
3092/**
3093 * smack_msg_msg_alloc_security - Set the security blob for msg_msg
3094 * @msg: the object
3095 *
3096 * Returns 0
3097 */
3098static int smack_msg_msg_alloc_security(struct msg_msg *msg)
3099{
3100 struct smack_known **blob = smack_msg_msg(msg);
3101
3102 *blob = smk_of_current();
3103 return 0;
3104}
3105
3106/**
3107 * smack_of_ipc - the smack pointer for the ipc
3108 * @isp: the object
3109 *
3110 * Returns a pointer to the smack value
3111 */
3112static struct smack_known *smack_of_ipc(struct kern_ipc_perm *isp)
3113{
3114 struct smack_known **blob = smack_ipc(isp);
3115
3116 return *blob;
3117}
3118
3119/**
3120 * smack_ipc_alloc_security - Set the security blob for ipc
3121 * @isp: the object
3122 *
3123 * Returns 0
3124 */
3125static int smack_ipc_alloc_security(struct kern_ipc_perm *isp)
3126{
3127 struct smack_known **blob = smack_ipc(isp);
3128
3129 *blob = smk_of_current();
3130 return 0;
3131}
3132
3133/**
3134 * smk_curacc_shm : check if current has access on shm
3135 * @isp : the object
3136 * @access : access requested
3137 *
3138 * Returns 0 if current has the requested access, error code otherwise
3139 */
3140static int smk_curacc_shm(struct kern_ipc_perm *isp, int access)
3141{
3142 struct smack_known *ssp = smack_of_ipc(isp);
3143 struct smk_audit_info ad;
3144 int rc;
3145
3146#ifdef CONFIG_AUDIT
3147 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
3148 ad.a.u.ipc_id = isp->id;
3149#endif
3150 rc = smk_curacc(ssp, access, &ad);
3151 rc = smk_bu_current("shm", ssp, access, rc);
3152 return rc;
3153}
3154
3155/**
3156 * smack_shm_associate - Smack access check for shm
3157 * @isp: the object
3158 * @shmflg: access requested
3159 *
3160 * Returns 0 if current has the requested access, error code otherwise
3161 */
3162static int smack_shm_associate(struct kern_ipc_perm *isp, int shmflg)
3163{
3164 int may;
3165
3166 may = smack_flags_to_may(shmflg);
3167 return smk_curacc_shm(isp, may);
3168}
3169
3170/**
3171 * smack_shm_shmctl - Smack access check for shm
3172 * @isp: the object
3173 * @cmd: what it wants to do
3174 *
3175 * Returns 0 if current has the requested access, error code otherwise
3176 */
3177static int smack_shm_shmctl(struct kern_ipc_perm *isp, int cmd)
3178{
3179 int may;
3180
3181 switch (cmd) {
3182 case IPC_STAT:
3183 case SHM_STAT:
3184 case SHM_STAT_ANY:
3185 may = MAY_READ;
3186 break;
3187 case IPC_SET:
3188 case SHM_LOCK:
3189 case SHM_UNLOCK:
3190 case IPC_RMID:
3191 may = MAY_READWRITE;
3192 break;
3193 case IPC_INFO:
3194 case SHM_INFO:
3195 /*
3196 * System level information.
3197 */
3198 return 0;
3199 default:
3200 return -EINVAL;
3201 }
3202 return smk_curacc_shm(isp, may);
3203}
3204
3205/**
3206 * smack_shm_shmat - Smack access for shmat
3207 * @isp: the object
3208 * @shmaddr: unused
3209 * @shmflg: access requested
3210 *
3211 * Returns 0 if current has the requested access, error code otherwise
3212 */
3213static int smack_shm_shmat(struct kern_ipc_perm *isp, char __user *shmaddr,
3214 int shmflg)
3215{
3216 int may;
3217
3218 may = smack_flags_to_may(shmflg);
3219 return smk_curacc_shm(isp, may);
3220}
3221
3222/**
3223 * smk_curacc_sem : check if current has access on sem
3224 * @isp : the object
3225 * @access : access requested
3226 *
3227 * Returns 0 if current has the requested access, error code otherwise
3228 */
3229static int smk_curacc_sem(struct kern_ipc_perm *isp, int access)
3230{
3231 struct smack_known *ssp = smack_of_ipc(isp);
3232 struct smk_audit_info ad;
3233 int rc;
3234
3235#ifdef CONFIG_AUDIT
3236 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
3237 ad.a.u.ipc_id = isp->id;
3238#endif
3239 rc = smk_curacc(ssp, access, &ad);
3240 rc = smk_bu_current("sem", ssp, access, rc);
3241 return rc;
3242}
3243
3244/**
3245 * smack_sem_associate - Smack access check for sem
3246 * @isp: the object
3247 * @semflg: access requested
3248 *
3249 * Returns 0 if current has the requested access, error code otherwise
3250 */
3251static int smack_sem_associate(struct kern_ipc_perm *isp, int semflg)
3252{
3253 int may;
3254
3255 may = smack_flags_to_may(semflg);
3256 return smk_curacc_sem(isp, may);
3257}
3258
3259/**
3260 * smack_sem_semctl - Smack access check for sem
3261 * @isp: the object
3262 * @cmd: what it wants to do
3263 *
3264 * Returns 0 if current has the requested access, error code otherwise
3265 */
3266static int smack_sem_semctl(struct kern_ipc_perm *isp, int cmd)
3267{
3268 int may;
3269
3270 switch (cmd) {
3271 case GETPID:
3272 case GETNCNT:
3273 case GETZCNT:
3274 case GETVAL:
3275 case GETALL:
3276 case IPC_STAT:
3277 case SEM_STAT:
3278 case SEM_STAT_ANY:
3279 may = MAY_READ;
3280 break;
3281 case SETVAL:
3282 case SETALL:
3283 case IPC_RMID:
3284 case IPC_SET:
3285 may = MAY_READWRITE;
3286 break;
3287 case IPC_INFO:
3288 case SEM_INFO:
3289 /*
3290 * System level information
3291 */
3292 return 0;
3293 default:
3294 return -EINVAL;
3295 }
3296
3297 return smk_curacc_sem(isp, may);
3298}
3299
3300/**
3301 * smack_sem_semop - Smack checks of semaphore operations
3302 * @isp: the object
3303 * @sops: unused
3304 * @nsops: unused
3305 * @alter: unused
3306 *
3307 * Treated as read and write in all cases.
3308 *
3309 * Returns 0 if access is allowed, error code otherwise
3310 */
3311static int smack_sem_semop(struct kern_ipc_perm *isp, struct sembuf *sops,
3312 unsigned nsops, int alter)
3313{
3314 return smk_curacc_sem(isp, MAY_READWRITE);
3315}
3316
3317/**
3318 * smk_curacc_msq : helper to check if current has access on msq
3319 * @isp : the msq
3320 * @access : access requested
3321 *
3322 * return 0 if current has access, error otherwise
3323 */
3324static int smk_curacc_msq(struct kern_ipc_perm *isp, int access)
3325{
3326 struct smack_known *msp = smack_of_ipc(isp);
3327 struct smk_audit_info ad;
3328 int rc;
3329
3330#ifdef CONFIG_AUDIT
3331 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
3332 ad.a.u.ipc_id = isp->id;
3333#endif
3334 rc = smk_curacc(msp, access, &ad);
3335 rc = smk_bu_current("msq", msp, access, rc);
3336 return rc;
3337}
3338
3339/**
3340 * smack_msg_queue_associate - Smack access check for msg_queue
3341 * @isp: the object
3342 * @msqflg: access requested
3343 *
3344 * Returns 0 if current has the requested access, error code otherwise
3345 */
3346static int smack_msg_queue_associate(struct kern_ipc_perm *isp, int msqflg)
3347{
3348 int may;
3349
3350 may = smack_flags_to_may(msqflg);
3351 return smk_curacc_msq(isp, may);
3352}
3353
3354/**
3355 * smack_msg_queue_msgctl - Smack access check for msg_queue
3356 * @isp: the object
3357 * @cmd: what it wants to do
3358 *
3359 * Returns 0 if current has the requested access, error code otherwise
3360 */
3361static int smack_msg_queue_msgctl(struct kern_ipc_perm *isp, int cmd)
3362{
3363 int may;
3364
3365 switch (cmd) {
3366 case IPC_STAT:
3367 case MSG_STAT:
3368 case MSG_STAT_ANY:
3369 may = MAY_READ;
3370 break;
3371 case IPC_SET:
3372 case IPC_RMID:
3373 may = MAY_READWRITE;
3374 break;
3375 case IPC_INFO:
3376 case MSG_INFO:
3377 /*
3378 * System level information
3379 */
3380 return 0;
3381 default:
3382 return -EINVAL;
3383 }
3384
3385 return smk_curacc_msq(isp, may);
3386}
3387
3388/**
3389 * smack_msg_queue_msgsnd - Smack access check for msg_queue
3390 * @isp: the object
3391 * @msg: unused
3392 * @msqflg: access requested
3393 *
3394 * Returns 0 if current has the requested access, error code otherwise
3395 */
3396static int smack_msg_queue_msgsnd(struct kern_ipc_perm *isp, struct msg_msg *msg,
3397 int msqflg)
3398{
3399 int may;
3400
3401 may = smack_flags_to_may(msqflg);
3402 return smk_curacc_msq(isp, may);
3403}
3404
3405/**
3406 * smack_msg_queue_msgrcv - Smack access check for msg_queue
3407 * @isp: the object
3408 * @msg: unused
3409 * @target: unused
3410 * @type: unused
3411 * @mode: unused
3412 *
3413 * Returns 0 if current has read and write access, error code otherwise
3414 */
3415static int smack_msg_queue_msgrcv(struct kern_ipc_perm *isp,
3416 struct msg_msg *msg,
3417 struct task_struct *target, long type,
3418 int mode)
3419{
3420 return smk_curacc_msq(isp, MAY_READWRITE);
3421}
3422
3423/**
3424 * smack_ipc_permission - Smack access for ipc_permission()
3425 * @ipp: the object permissions
3426 * @flag: access requested
3427 *
3428 * Returns 0 if current has read and write access, error code otherwise
3429 */
3430static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag)
3431{
3432 struct smack_known **blob = smack_ipc(ipp);
3433 struct smack_known *iskp = *blob;
3434 int may = smack_flags_to_may(flag);
3435 struct smk_audit_info ad;
3436 int rc;
3437
3438#ifdef CONFIG_AUDIT
3439 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
3440 ad.a.u.ipc_id = ipp->id;
3441#endif
3442 rc = smk_curacc(iskp, may, &ad);
3443 rc = smk_bu_current("svipc", iskp, may, rc);
3444 return rc;
3445}
3446
3447/**
3448 * smack_ipc_getlsmprop - Extract smack security data
3449 * @ipp: the object permissions
3450 * @prop: where result will be saved
3451 */
3452static void smack_ipc_getlsmprop(struct kern_ipc_perm *ipp, struct lsm_prop *prop)
3453{
3454 struct smack_known **iskpp = smack_ipc(ipp);
3455
3456 prop->smack.skp = *iskpp;
3457}
3458
3459/**
3460 * smack_d_instantiate - Make sure the blob is correct on an inode
3461 * @opt_dentry: dentry where inode will be attached
3462 * @inode: the object
3463 *
3464 * Set the inode's security blob if it hasn't been done already.
3465 */
3466static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
3467{
3468 struct super_block *sbp;
3469 struct superblock_smack *sbsp;
3470 struct inode_smack *isp;
3471 struct smack_known *skp;
3472 struct smack_known *ckp = smk_of_current();
3473 struct smack_known *final;
3474 char trattr[TRANS_TRUE_SIZE];
3475 int transflag = 0;
3476 int rc;
3477 struct dentry *dp;
3478
3479 if (inode == NULL)
3480 return;
3481
3482 isp = smack_inode(inode);
3483
3484 /*
3485 * If the inode is already instantiated
3486 * take the quick way out
3487 */
3488 if (isp->smk_flags & SMK_INODE_INSTANT)
3489 return;
3490
3491 sbp = inode->i_sb;
3492 sbsp = smack_superblock(sbp);
3493 /*
3494 * We're going to use the superblock default label
3495 * if there's no label on the file.
3496 */
3497 final = sbsp->smk_default;
3498
3499 /*
3500 * If this is the root inode the superblock
3501 * may be in the process of initialization.
3502 * If that is the case use the root value out
3503 * of the superblock.
3504 */
3505 if (opt_dentry->d_parent == opt_dentry) {
3506 switch (sbp->s_magic) {
3507 case CGROUP_SUPER_MAGIC:
3508 case CGROUP2_SUPER_MAGIC:
3509 /*
3510 * The cgroup filesystem is never mounted,
3511 * so there's no opportunity to set the mount
3512 * options.
3513 */
3514 sbsp->smk_root = &smack_known_star;
3515 sbsp->smk_default = &smack_known_star;
3516 isp->smk_inode = sbsp->smk_root;
3517 break;
3518 case TMPFS_MAGIC:
3519 /*
3520 * What about shmem/tmpfs anonymous files with dentry
3521 * obtained from d_alloc_pseudo()?
3522 */
3523 isp->smk_inode = smk_of_current();
3524 break;
3525 case PIPEFS_MAGIC:
3526 isp->smk_inode = smk_of_current();
3527 break;
3528 case SOCKFS_MAGIC:
3529 /*
3530 * Socket access is controlled by the socket
3531 * structures associated with the task involved.
3532 */
3533 isp->smk_inode = &smack_known_star;
3534 break;
3535 default:
3536 isp->smk_inode = sbsp->smk_root;
3537 break;
3538 }
3539 isp->smk_flags |= SMK_INODE_INSTANT;
3540 return;
3541 }
3542
3543 /*
3544 * This is pretty hackish.
3545 * Casey says that we shouldn't have to do
3546 * file system specific code, but it does help
3547 * with keeping it simple.
3548 */
3549 switch (sbp->s_magic) {
3550 case SMACK_MAGIC:
3551 case CGROUP_SUPER_MAGIC:
3552 case CGROUP2_SUPER_MAGIC:
3553 /*
3554 * Casey says that it's a little embarrassing
3555 * that the smack file system doesn't do
3556 * extended attributes.
3557 *
3558 * Cgroupfs is special
3559 */
3560 final = &smack_known_star;
3561 break;
3562 case DEVPTS_SUPER_MAGIC:
3563 /*
3564 * devpts seems content with the label of the task.
3565 * Programs that change smack have to treat the
3566 * pty with respect.
3567 */
3568 final = ckp;
3569 break;
3570 case PROC_SUPER_MAGIC:
3571 /*
3572 * Casey says procfs appears not to care.
3573 * The superblock default suffices.
3574 */
3575 break;
3576 case TMPFS_MAGIC:
3577 /*
3578 * Device labels should come from the filesystem,
3579 * but watch out, because they're volitile,
3580 * getting recreated on every reboot.
3581 */
3582 final = &smack_known_star;
3583 /*
3584 * If a smack value has been set we want to use it,
3585 * but since tmpfs isn't giving us the opportunity
3586 * to set mount options simulate setting the
3587 * superblock default.
3588 */
3589 fallthrough;
3590 default:
3591 /*
3592 * This isn't an understood special case.
3593 * Get the value from the xattr.
3594 */
3595
3596 /*
3597 * UNIX domain sockets use lower level socket data.
3598 */
3599 if (S_ISSOCK(inode->i_mode)) {
3600 final = &smack_known_star;
3601 break;
3602 }
3603 /*
3604 * No xattr support means, alas, no SMACK label.
3605 * Use the aforeapplied default.
3606 * It would be curious if the label of the task
3607 * does not match that assigned.
3608 */
3609 if (!(inode->i_opflags & IOP_XATTR))
3610 break;
3611 /*
3612 * Get the dentry for xattr.
3613 */
3614 dp = dget(opt_dentry);
3615 skp = smk_fetch(XATTR_NAME_SMACK, inode, dp);
3616 if (!IS_ERR_OR_NULL(skp))
3617 final = skp;
3618
3619 /*
3620 * Transmuting directory
3621 */
3622 if (S_ISDIR(inode->i_mode)) {
3623 /*
3624 * If this is a new directory and the label was
3625 * transmuted when the inode was initialized
3626 * set the transmute attribute on the directory
3627 * and mark the inode.
3628 *
3629 * If there is a transmute attribute on the
3630 * directory mark the inode.
3631 */
3632 rc = __vfs_getxattr(dp, inode,
3633 XATTR_NAME_SMACKTRANSMUTE, trattr,
3634 TRANS_TRUE_SIZE);
3635 if (rc >= 0 && strncmp(trattr, TRANS_TRUE,
3636 TRANS_TRUE_SIZE) != 0)
3637 rc = -EINVAL;
3638 if (rc >= 0)
3639 transflag = SMK_INODE_TRANSMUTE;
3640 }
3641 /*
3642 * Don't let the exec or mmap label be "*" or "@".
3643 */
3644 skp = smk_fetch(XATTR_NAME_SMACKEXEC, inode, dp);
3645 if (IS_ERR(skp) || skp == &smack_known_star ||
3646 skp == &smack_known_web)
3647 skp = NULL;
3648 isp->smk_task = skp;
3649
3650 skp = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp);
3651 if (IS_ERR(skp) || skp == &smack_known_star ||
3652 skp == &smack_known_web)
3653 skp = NULL;
3654 isp->smk_mmap = skp;
3655
3656 dput(dp);
3657 break;
3658 }
3659
3660 if (final == NULL)
3661 isp->smk_inode = ckp;
3662 else
3663 isp->smk_inode = final;
3664
3665 isp->smk_flags |= (SMK_INODE_INSTANT | transflag);
3666
3667 return;
3668}
3669
3670/**
3671 * smack_getselfattr - Smack current process attribute
3672 * @attr: which attribute to fetch
3673 * @ctx: buffer to receive the result
3674 * @size: available size in, actual size out
3675 * @flags: unused
3676 *
3677 * Fill the passed user space @ctx with the details of the requested
3678 * attribute.
3679 *
3680 * Returns the number of attributes on success, an error code otherwise.
3681 * There will only ever be one attribute.
3682 */
3683static int smack_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
3684 u32 *size, u32 flags)
3685{
3686 int rc;
3687 struct smack_known *skp;
3688
3689 if (attr != LSM_ATTR_CURRENT)
3690 return -EOPNOTSUPP;
3691
3692 skp = smk_of_current();
3693 rc = lsm_fill_user_ctx(ctx, size,
3694 skp->smk_known, strlen(skp->smk_known) + 1,
3695 LSM_ID_SMACK, 0);
3696 return (!rc ? 1 : rc);
3697}
3698
3699/**
3700 * smack_getprocattr - Smack process attribute access
3701 * @p: the object task
3702 * @name: the name of the attribute in /proc/.../attr
3703 * @value: where to put the result
3704 *
3705 * Places a copy of the task Smack into value
3706 *
3707 * Returns the length of the smack label or an error code
3708 */
3709static int smack_getprocattr(struct task_struct *p, const char *name, char **value)
3710{
3711 struct smack_known *skp = smk_of_task_struct_obj(p);
3712 char *cp;
3713 int slen;
3714
3715 if (strcmp(name, "current") != 0)
3716 return -EINVAL;
3717
3718 cp = kstrdup(skp->smk_known, GFP_KERNEL);
3719 if (cp == NULL)
3720 return -ENOMEM;
3721
3722 slen = strlen(cp);
3723 *value = cp;
3724 return slen;
3725}
3726
3727/**
3728 * do_setattr - Smack process attribute setting
3729 * @attr: the ID of the attribute
3730 * @value: the value to set
3731 * @size: the size of the value
3732 *
3733 * Sets the Smack value of the task. Only setting self
3734 * is permitted and only with privilege
3735 *
3736 * Returns the length of the smack label or an error code
3737 */
3738static int do_setattr(u64 attr, void *value, size_t size)
3739{
3740 struct task_smack *tsp = smack_cred(current_cred());
3741 struct cred *new;
3742 struct smack_known *skp;
3743 struct smack_known_list_elem *sklep;
3744 int rc;
3745
3746 if (!smack_privileged(CAP_MAC_ADMIN) && list_empty(&tsp->smk_relabel))
3747 return -EPERM;
3748
3749 if (value == NULL || size == 0 || size >= SMK_LONGLABEL)
3750 return -EINVAL;
3751
3752 if (attr != LSM_ATTR_CURRENT)
3753 return -EOPNOTSUPP;
3754
3755 skp = smk_import_entry(value, size);
3756 if (IS_ERR(skp))
3757 return PTR_ERR(skp);
3758
3759 /*
3760 * No process is ever allowed the web ("@") label
3761 * and the star ("*") label.
3762 */
3763 if (skp == &smack_known_web || skp == &smack_known_star)
3764 return -EINVAL;
3765
3766 if (!smack_privileged(CAP_MAC_ADMIN)) {
3767 rc = -EPERM;
3768 list_for_each_entry(sklep, &tsp->smk_relabel, list)
3769 if (sklep->smk_label == skp) {
3770 rc = 0;
3771 break;
3772 }
3773 if (rc)
3774 return rc;
3775 }
3776
3777 new = prepare_creds();
3778 if (new == NULL)
3779 return -ENOMEM;
3780
3781 tsp = smack_cred(new);
3782 tsp->smk_task = skp;
3783 /*
3784 * process can change its label only once
3785 */
3786 smk_destroy_label_list(&tsp->smk_relabel);
3787
3788 commit_creds(new);
3789 return size;
3790}
3791
3792/**
3793 * smack_setselfattr - Set a Smack process attribute
3794 * @attr: which attribute to set
3795 * @ctx: buffer containing the data
3796 * @size: size of @ctx
3797 * @flags: unused
3798 *
3799 * Fill the passed user space @ctx with the details of the requested
3800 * attribute.
3801 *
3802 * Returns 0 on success, an error code otherwise.
3803 */
3804static int smack_setselfattr(unsigned int attr, struct lsm_ctx *ctx,
3805 u32 size, u32 flags)
3806{
3807 int rc;
3808
3809 rc = do_setattr(attr, ctx->ctx, ctx->ctx_len);
3810 if (rc > 0)
3811 return 0;
3812 return rc;
3813}
3814
3815/**
3816 * smack_setprocattr - Smack process attribute setting
3817 * @name: the name of the attribute in /proc/.../attr
3818 * @value: the value to set
3819 * @size: the size of the value
3820 *
3821 * Sets the Smack value of the task. Only setting self
3822 * is permitted and only with privilege
3823 *
3824 * Returns the length of the smack label or an error code
3825 */
3826static int smack_setprocattr(const char *name, void *value, size_t size)
3827{
3828 int attr = lsm_name_to_attr(name);
3829
3830 if (attr != LSM_ATTR_UNDEF)
3831 return do_setattr(attr, value, size);
3832 return -EINVAL;
3833}
3834
3835/**
3836 * smack_unix_stream_connect - Smack access on UDS
3837 * @sock: one sock
3838 * @other: the other sock
3839 * @newsk: unused
3840 *
3841 * Return 0 if a subject with the smack of sock could access
3842 * an object with the smack of other, otherwise an error code
3843 */
3844static int smack_unix_stream_connect(struct sock *sock,
3845 struct sock *other, struct sock *newsk)
3846{
3847 struct smack_known *skp;
3848 struct smack_known *okp;
3849 struct socket_smack *ssp = smack_sock(sock);
3850 struct socket_smack *osp = smack_sock(other);
3851 struct socket_smack *nsp = smack_sock(newsk);
3852 struct smk_audit_info ad;
3853 int rc = 0;
3854#ifdef CONFIG_AUDIT
3855 struct lsm_network_audit net;
3856#endif
3857
3858 if (!smack_privileged(CAP_MAC_OVERRIDE)) {
3859 skp = ssp->smk_out;
3860 okp = osp->smk_in;
3861#ifdef CONFIG_AUDIT
3862 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
3863 smk_ad_setfield_u_net_sk(&ad, other);
3864#endif
3865 rc = smk_access(skp, okp, MAY_WRITE, &ad);
3866 rc = smk_bu_note("UDS connect", skp, okp, MAY_WRITE, rc);
3867 if (rc == 0) {
3868 okp = osp->smk_out;
3869 skp = ssp->smk_in;
3870 rc = smk_access(okp, skp, MAY_WRITE, &ad);
3871 rc = smk_bu_note("UDS connect", okp, skp,
3872 MAY_WRITE, rc);
3873 }
3874 }
3875
3876 if (rc == 0) {
3877 /*
3878 * Cross reference the peer labels for SO_PEERSEC.
3879 */
3880 nsp->smk_packet = ssp->smk_out;
3881 ssp->smk_packet = osp->smk_out;
3882
3883 /*
3884 * new/child/established socket must inherit listening socket labels
3885 */
3886 nsp->smk_out = osp->smk_out;
3887 nsp->smk_in = osp->smk_in;
3888 }
3889
3890 return rc;
3891}
3892
3893/**
3894 * smack_unix_may_send - Smack access on UDS
3895 * @sock: one socket
3896 * @other: the other socket
3897 *
3898 * Return 0 if a subject with the smack of sock could access
3899 * an object with the smack of other, otherwise an error code
3900 */
3901static int smack_unix_may_send(struct socket *sock, struct socket *other)
3902{
3903 struct socket_smack *ssp = smack_sock(sock->sk);
3904 struct socket_smack *osp = smack_sock(other->sk);
3905 struct smk_audit_info ad;
3906 int rc;
3907
3908#ifdef CONFIG_AUDIT
3909 struct lsm_network_audit net;
3910
3911 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
3912 smk_ad_setfield_u_net_sk(&ad, other->sk);
3913#endif
3914
3915 if (smack_privileged(CAP_MAC_OVERRIDE))
3916 return 0;
3917
3918 rc = smk_access(ssp->smk_out, osp->smk_in, MAY_WRITE, &ad);
3919 rc = smk_bu_note("UDS send", ssp->smk_out, osp->smk_in, MAY_WRITE, rc);
3920 return rc;
3921}
3922
3923/**
3924 * smack_socket_sendmsg - Smack check based on destination host
3925 * @sock: the socket
3926 * @msg: the message
3927 * @size: the size of the message
3928 *
3929 * Return 0 if the current subject can write to the destination host.
3930 * For IPv4 this is only a question if the destination is a single label host.
3931 * For IPv6 this is a check against the label of the port.
3932 */
3933static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3934 int size)
3935{
3936 struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name;
3937#if IS_ENABLED(CONFIG_IPV6)
3938 struct sockaddr_in6 *sap = (struct sockaddr_in6 *) msg->msg_name;
3939#endif
3940#ifdef SMACK_IPV6_SECMARK_LABELING
3941 struct socket_smack *ssp = smack_sock(sock->sk);
3942 struct smack_known *rsp;
3943#endif
3944 int rc = 0;
3945
3946 /*
3947 * Perfectly reasonable for this to be NULL
3948 */
3949 if (sip == NULL)
3950 return 0;
3951
3952 switch (sock->sk->sk_family) {
3953 case AF_INET:
3954 if (msg->msg_namelen < sizeof(struct sockaddr_in) ||
3955 sip->sin_family != AF_INET)
3956 return -EINVAL;
3957 rc = smk_ipv4_check(sock->sk, sip);
3958 break;
3959#if IS_ENABLED(CONFIG_IPV6)
3960 case AF_INET6:
3961 if (msg->msg_namelen < SIN6_LEN_RFC2133 ||
3962 sap->sin6_family != AF_INET6)
3963 return -EINVAL;
3964#ifdef SMACK_IPV6_SECMARK_LABELING
3965 rsp = smack_ipv6host_label(sap);
3966 if (rsp != NULL)
3967 rc = smk_ipv6_check(ssp->smk_out, rsp, sap,
3968 SMK_CONNECTING);
3969#endif
3970#ifdef SMACK_IPV6_PORT_LABELING
3971 rc = smk_ipv6_port_check(sock->sk, sap, SMK_SENDING);
3972#endif
3973#endif /* IS_ENABLED(CONFIG_IPV6) */
3974 break;
3975 }
3976 return rc;
3977}
3978
3979/**
3980 * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat pair to smack
3981 * @sap: netlabel secattr
3982 * @ssp: socket security information
3983 *
3984 * Returns a pointer to a Smack label entry found on the label list.
3985 */
3986static struct smack_known *smack_from_secattr(struct netlbl_lsm_secattr *sap,
3987 struct socket_smack *ssp)
3988{
3989 struct smack_known *skp;
3990 int found = 0;
3991 int acat;
3992 int kcat;
3993
3994 /*
3995 * Netlabel found it in the cache.
3996 */
3997 if ((sap->flags & NETLBL_SECATTR_CACHE) != 0)
3998 return (struct smack_known *)sap->cache->data;
3999
4000 if ((sap->flags & NETLBL_SECATTR_SECID) != 0)
4001 /*
4002 * Looks like a fallback, which gives us a secid.
4003 */
4004 return smack_from_secid(sap->attr.secid);
4005
4006 if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) {
4007 /*
4008 * Looks like a CIPSO packet.
4009 * If there are flags but no level netlabel isn't
4010 * behaving the way we expect it to.
4011 *
4012 * Look it up in the label table
4013 * Without guidance regarding the smack value
4014 * for the packet fall back on the network
4015 * ambient value.
4016 */
4017 rcu_read_lock();
4018 list_for_each_entry_rcu(skp, &smack_known_list, list) {
4019 if (sap->attr.mls.lvl != skp->smk_netlabel.attr.mls.lvl)
4020 continue;
4021 /*
4022 * Compare the catsets. Use the netlbl APIs.
4023 */
4024 if ((sap->flags & NETLBL_SECATTR_MLS_CAT) == 0) {
4025 if ((skp->smk_netlabel.flags &
4026 NETLBL_SECATTR_MLS_CAT) == 0)
4027 found = 1;
4028 break;
4029 }
4030 for (acat = -1, kcat = -1; acat == kcat; ) {
4031 acat = netlbl_catmap_walk(sap->attr.mls.cat,
4032 acat + 1);
4033 kcat = netlbl_catmap_walk(
4034 skp->smk_netlabel.attr.mls.cat,
4035 kcat + 1);
4036 if (acat < 0 || kcat < 0)
4037 break;
4038 }
4039 if (acat == kcat) {
4040 found = 1;
4041 break;
4042 }
4043 }
4044 rcu_read_unlock();
4045
4046 if (found)
4047 return skp;
4048
4049 if (ssp != NULL && ssp->smk_in == &smack_known_star)
4050 return &smack_known_web;
4051 return &smack_known_star;
4052 }
4053 /*
4054 * Without guidance regarding the smack value
4055 * for the packet fall back on the network
4056 * ambient value.
4057 */
4058 return smack_net_ambient;
4059}
4060
4061#if IS_ENABLED(CONFIG_IPV6)
4062static int smk_skb_to_addr_ipv6(struct sk_buff *skb, struct sockaddr_in6 *sip)
4063{
4064 u8 nexthdr;
4065 int offset;
4066 int proto = -EINVAL;
4067 struct ipv6hdr _ipv6h;
4068 struct ipv6hdr *ip6;
4069 __be16 frag_off;
4070 struct tcphdr _tcph, *th;
4071 struct udphdr _udph, *uh;
4072 struct dccp_hdr _dccph, *dh;
4073
4074 sip->sin6_port = 0;
4075
4076 offset = skb_network_offset(skb);
4077 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4078 if (ip6 == NULL)
4079 return -EINVAL;
4080 sip->sin6_addr = ip6->saddr;
4081
4082 nexthdr = ip6->nexthdr;
4083 offset += sizeof(_ipv6h);
4084 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4085 if (offset < 0)
4086 return -EINVAL;
4087
4088 proto = nexthdr;
4089 switch (proto) {
4090 case IPPROTO_TCP:
4091 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4092 if (th != NULL)
4093 sip->sin6_port = th->source;
4094 break;
4095 case IPPROTO_UDP:
4096 case IPPROTO_UDPLITE:
4097 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4098 if (uh != NULL)
4099 sip->sin6_port = uh->source;
4100 break;
4101 case IPPROTO_DCCP:
4102 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4103 if (dh != NULL)
4104 sip->sin6_port = dh->dccph_sport;
4105 break;
4106 }
4107 return proto;
4108}
4109#endif /* CONFIG_IPV6 */
4110
4111/**
4112 * smack_from_skb - Smack data from the secmark in an skb
4113 * @skb: packet
4114 *
4115 * Returns smack_known of the secmark or NULL if that won't work.
4116 */
4117#ifdef CONFIG_NETWORK_SECMARK
4118static struct smack_known *smack_from_skb(struct sk_buff *skb)
4119{
4120 if (skb == NULL || skb->secmark == 0)
4121 return NULL;
4122
4123 return smack_from_secid(skb->secmark);
4124}
4125#else
4126static inline struct smack_known *smack_from_skb(struct sk_buff *skb)
4127{
4128 return NULL;
4129}
4130#endif
4131
4132/**
4133 * smack_from_netlbl - Smack data from the IP options in an skb
4134 * @sk: socket data came in on
4135 * @family: address family
4136 * @skb: packet
4137 *
4138 * Find the Smack label in the IP options. If it hasn't been
4139 * added to the netlabel cache, add it here.
4140 *
4141 * Returns smack_known of the IP options or NULL if that won't work.
4142 */
4143static struct smack_known *smack_from_netlbl(const struct sock *sk, u16 family,
4144 struct sk_buff *skb)
4145{
4146 struct netlbl_lsm_secattr secattr;
4147 struct socket_smack *ssp = NULL;
4148 struct smack_known *skp = NULL;
4149
4150 netlbl_secattr_init(&secattr);
4151
4152 if (sk)
4153 ssp = smack_sock(sk);
4154
4155 if (netlbl_skbuff_getattr(skb, family, &secattr) == 0) {
4156 skp = smack_from_secattr(&secattr, ssp);
4157 if (secattr.flags & NETLBL_SECATTR_CACHEABLE)
4158 netlbl_cache_add(skb, family, &skp->smk_netlabel);
4159 }
4160
4161 netlbl_secattr_destroy(&secattr);
4162
4163 return skp;
4164}
4165
4166/**
4167 * smack_socket_sock_rcv_skb - Smack packet delivery access check
4168 * @sk: socket
4169 * @skb: packet
4170 *
4171 * Returns 0 if the packet should be delivered, an error code otherwise
4172 */
4173static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4174{
4175 struct socket_smack *ssp = smack_sock(sk);
4176 struct smack_known *skp = NULL;
4177 int rc = 0;
4178 struct smk_audit_info ad;
4179 u16 family = sk->sk_family;
4180#ifdef CONFIG_AUDIT
4181 struct lsm_network_audit net;
4182#endif
4183#if IS_ENABLED(CONFIG_IPV6)
4184 struct sockaddr_in6 sadd;
4185 int proto;
4186
4187 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4188 family = PF_INET;
4189#endif /* CONFIG_IPV6 */
4190
4191 switch (family) {
4192 case PF_INET:
4193 /*
4194 * If there is a secmark use it rather than the CIPSO label.
4195 * If there is no secmark fall back to CIPSO.
4196 * The secmark is assumed to reflect policy better.
4197 */
4198 skp = smack_from_skb(skb);
4199 if (skp == NULL) {
4200 skp = smack_from_netlbl(sk, family, skb);
4201 if (skp == NULL)
4202 skp = smack_net_ambient;
4203 }
4204
4205#ifdef CONFIG_AUDIT
4206 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
4207 ad.a.u.net->family = family;
4208 ad.a.u.net->netif = skb->skb_iif;
4209 ipv4_skb_to_auditdata(skb, &ad.a, NULL);
4210#endif
4211 /*
4212 * Receiving a packet requires that the other end
4213 * be able to write here. Read access is not required.
4214 * This is the simplist possible security model
4215 * for networking.
4216 */
4217 rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
4218 rc = smk_bu_note("IPv4 delivery", skp, ssp->smk_in,
4219 MAY_WRITE, rc);
4220 if (rc != 0)
4221 netlbl_skbuff_err(skb, family, rc, 0);
4222 break;
4223#if IS_ENABLED(CONFIG_IPV6)
4224 case PF_INET6:
4225 proto = smk_skb_to_addr_ipv6(skb, &sadd);
4226 if (proto != IPPROTO_UDP && proto != IPPROTO_UDPLITE &&
4227 proto != IPPROTO_TCP && proto != IPPROTO_DCCP)
4228 break;
4229#ifdef SMACK_IPV6_SECMARK_LABELING
4230 skp = smack_from_skb(skb);
4231 if (skp == NULL) {
4232 if (smk_ipv6_localhost(&sadd))
4233 break;
4234 skp = smack_ipv6host_label(&sadd);
4235 if (skp == NULL)
4236 skp = smack_net_ambient;
4237 }
4238#ifdef CONFIG_AUDIT
4239 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
4240 ad.a.u.net->family = family;
4241 ad.a.u.net->netif = skb->skb_iif;
4242 ipv6_skb_to_auditdata(skb, &ad.a, NULL);
4243#endif /* CONFIG_AUDIT */
4244 rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
4245 rc = smk_bu_note("IPv6 delivery", skp, ssp->smk_in,
4246 MAY_WRITE, rc);
4247#endif /* SMACK_IPV6_SECMARK_LABELING */
4248#ifdef SMACK_IPV6_PORT_LABELING
4249 rc = smk_ipv6_port_check(sk, &sadd, SMK_RECEIVING);
4250#endif /* SMACK_IPV6_PORT_LABELING */
4251 if (rc != 0)
4252 icmpv6_send(skb, ICMPV6_DEST_UNREACH,
4253 ICMPV6_ADM_PROHIBITED, 0);
4254 break;
4255#endif /* CONFIG_IPV6 */
4256 }
4257
4258 return rc;
4259}
4260
4261/**
4262 * smack_socket_getpeersec_stream - pull in packet label
4263 * @sock: the socket
4264 * @optval: user's destination
4265 * @optlen: size thereof
4266 * @len: max thereof
4267 *
4268 * returns zero on success, an error code otherwise
4269 */
4270static int smack_socket_getpeersec_stream(struct socket *sock,
4271 sockptr_t optval, sockptr_t optlen,
4272 unsigned int len)
4273{
4274 struct socket_smack *ssp;
4275 char *rcp = "";
4276 u32 slen = 1;
4277 int rc = 0;
4278
4279 ssp = smack_sock(sock->sk);
4280 if (ssp->smk_packet != NULL) {
4281 rcp = ssp->smk_packet->smk_known;
4282 slen = strlen(rcp) + 1;
4283 }
4284 if (slen > len) {
4285 rc = -ERANGE;
4286 goto out_len;
4287 }
4288
4289 if (copy_to_sockptr(optval, rcp, slen))
4290 rc = -EFAULT;
4291out_len:
4292 if (copy_to_sockptr(optlen, &slen, sizeof(slen)))
4293 rc = -EFAULT;
4294 return rc;
4295}
4296
4297
4298/**
4299 * smack_socket_getpeersec_dgram - pull in packet label
4300 * @sock: the peer socket
4301 * @skb: packet data
4302 * @secid: pointer to where to put the secid of the packet
4303 *
4304 * Sets the netlabel socket state on sk from parent
4305 */
4306static int smack_socket_getpeersec_dgram(struct socket *sock,
4307 struct sk_buff *skb, u32 *secid)
4308
4309{
4310 struct socket_smack *ssp = NULL;
4311 struct smack_known *skp;
4312 struct sock *sk = NULL;
4313 int family = PF_UNSPEC;
4314 u32 s = 0; /* 0 is the invalid secid */
4315
4316 if (skb != NULL) {
4317 if (skb->protocol == htons(ETH_P_IP))
4318 family = PF_INET;
4319#if IS_ENABLED(CONFIG_IPV6)
4320 else if (skb->protocol == htons(ETH_P_IPV6))
4321 family = PF_INET6;
4322#endif /* CONFIG_IPV6 */
4323 }
4324 if (family == PF_UNSPEC && sock != NULL)
4325 family = sock->sk->sk_family;
4326
4327 switch (family) {
4328 case PF_UNIX:
4329 ssp = smack_sock(sock->sk);
4330 s = ssp->smk_out->smk_secid;
4331 break;
4332 case PF_INET:
4333 skp = smack_from_skb(skb);
4334 if (skp) {
4335 s = skp->smk_secid;
4336 break;
4337 }
4338 /*
4339 * Translate what netlabel gave us.
4340 */
4341 if (sock != NULL)
4342 sk = sock->sk;
4343 skp = smack_from_netlbl(sk, family, skb);
4344 if (skp != NULL)
4345 s = skp->smk_secid;
4346 break;
4347 case PF_INET6:
4348#ifdef SMACK_IPV6_SECMARK_LABELING
4349 skp = smack_from_skb(skb);
4350 if (skp)
4351 s = skp->smk_secid;
4352#endif
4353 break;
4354 }
4355 *secid = s;
4356 if (s == 0)
4357 return -EINVAL;
4358 return 0;
4359}
4360
4361/**
4362 * smack_sock_graft - Initialize a newly created socket with an existing sock
4363 * @sk: child sock
4364 * @parent: parent socket
4365 *
4366 * Set the smk_{in,out} state of an existing sock based on the process that
4367 * is creating the new socket.
4368 */
4369static void smack_sock_graft(struct sock *sk, struct socket *parent)
4370{
4371 struct socket_smack *ssp;
4372 struct smack_known *skp = smk_of_current();
4373
4374 if (sk == NULL ||
4375 (sk->sk_family != PF_INET && sk->sk_family != PF_INET6))
4376 return;
4377
4378 ssp = smack_sock(sk);
4379 ssp->smk_in = skp;
4380 ssp->smk_out = skp;
4381 /* cssp->smk_packet is already set in smack_inet_csk_clone() */
4382}
4383
4384/**
4385 * smack_inet_conn_request - Smack access check on connect
4386 * @sk: socket involved
4387 * @skb: packet
4388 * @req: unused
4389 *
4390 * Returns 0 if a task with the packet label could write to
4391 * the socket, otherwise an error code
4392 */
4393static int smack_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
4394 struct request_sock *req)
4395{
4396 u16 family = sk->sk_family;
4397 struct smack_known *skp;
4398 struct socket_smack *ssp = smack_sock(sk);
4399 struct sockaddr_in addr;
4400 struct iphdr *hdr;
4401 struct smack_known *hskp;
4402 int rc;
4403 struct smk_audit_info ad;
4404#ifdef CONFIG_AUDIT
4405 struct lsm_network_audit net;
4406#endif
4407
4408#if IS_ENABLED(CONFIG_IPV6)
4409 if (family == PF_INET6) {
4410 /*
4411 * Handle mapped IPv4 packets arriving
4412 * via IPv6 sockets. Don't set up netlabel
4413 * processing on IPv6.
4414 */
4415 if (skb->protocol == htons(ETH_P_IP))
4416 family = PF_INET;
4417 else
4418 return 0;
4419 }
4420#endif /* CONFIG_IPV6 */
4421
4422 /*
4423 * If there is a secmark use it rather than the CIPSO label.
4424 * If there is no secmark fall back to CIPSO.
4425 * The secmark is assumed to reflect policy better.
4426 */
4427 skp = smack_from_skb(skb);
4428 if (skp == NULL) {
4429 skp = smack_from_netlbl(sk, family, skb);
4430 if (skp == NULL)
4431 skp = &smack_known_huh;
4432 }
4433
4434#ifdef CONFIG_AUDIT
4435 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
4436 ad.a.u.net->family = family;
4437 ad.a.u.net->netif = skb->skb_iif;
4438 ipv4_skb_to_auditdata(skb, &ad.a, NULL);
4439#endif
4440 /*
4441 * Receiving a packet requires that the other end be able to write
4442 * here. Read access is not required.
4443 */
4444 rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
4445 rc = smk_bu_note("IPv4 connect", skp, ssp->smk_in, MAY_WRITE, rc);
4446 if (rc != 0)
4447 return rc;
4448
4449 /*
4450 * Save the peer's label in the request_sock so we can later setup
4451 * smk_packet in the child socket so that SO_PEERCRED can report it.
4452 */
4453 req->peer_secid = skp->smk_secid;
4454
4455 /*
4456 * We need to decide if we want to label the incoming connection here
4457 * if we do we only need to label the request_sock and the stack will
4458 * propagate the wire-label to the sock when it is created.
4459 */
4460 hdr = ip_hdr(skb);
4461 addr.sin_addr.s_addr = hdr->saddr;
4462 rcu_read_lock();
4463 hskp = smack_ipv4host_label(&addr);
4464 rcu_read_unlock();
4465
4466 if (hskp == NULL)
4467 rc = netlbl_req_setattr(req, &ssp->smk_out->smk_netlabel);
4468 else
4469 netlbl_req_delattr(req);
4470
4471 return rc;
4472}
4473
4474/**
4475 * smack_inet_csk_clone - Copy the connection information to the new socket
4476 * @sk: the new socket
4477 * @req: the connection's request_sock
4478 *
4479 * Transfer the connection's peer label to the newly created socket.
4480 */
4481static void smack_inet_csk_clone(struct sock *sk,
4482 const struct request_sock *req)
4483{
4484 struct socket_smack *ssp = smack_sock(sk);
4485 struct smack_known *skp;
4486
4487 if (req->peer_secid != 0) {
4488 skp = smack_from_secid(req->peer_secid);
4489 ssp->smk_packet = skp;
4490 } else
4491 ssp->smk_packet = NULL;
4492}
4493
4494/*
4495 * Key management security hooks
4496 *
4497 * Casey has not tested key support very heavily.
4498 * The permission check is most likely too restrictive.
4499 * If you care about keys please have a look.
4500 */
4501#ifdef CONFIG_KEYS
4502
4503/**
4504 * smack_key_alloc - Set the key security blob
4505 * @key: object
4506 * @cred: the credentials to use
4507 * @flags: unused
4508 *
4509 * No allocation required
4510 *
4511 * Returns 0
4512 */
4513static int smack_key_alloc(struct key *key, const struct cred *cred,
4514 unsigned long flags)
4515{
4516 struct smack_known **blob = smack_key(key);
4517 struct smack_known *skp = smk_of_task(smack_cred(cred));
4518
4519 *blob = skp;
4520 return 0;
4521}
4522
4523/**
4524 * smack_key_permission - Smack access on a key
4525 * @key_ref: gets to the object
4526 * @cred: the credentials to use
4527 * @need_perm: requested key permission
4528 *
4529 * Return 0 if the task has read and write to the object,
4530 * an error code otherwise
4531 */
4532static int smack_key_permission(key_ref_t key_ref,
4533 const struct cred *cred,
4534 enum key_need_perm need_perm)
4535{
4536 struct smack_known **blob;
4537 struct smack_known *skp;
4538 struct key *keyp;
4539 struct smk_audit_info ad;
4540 struct smack_known *tkp = smk_of_task(smack_cred(cred));
4541 int request = 0;
4542 int rc;
4543
4544 /*
4545 * Validate requested permissions
4546 */
4547 switch (need_perm) {
4548 case KEY_NEED_READ:
4549 case KEY_NEED_SEARCH:
4550 case KEY_NEED_VIEW:
4551 request |= MAY_READ;
4552 break;
4553 case KEY_NEED_WRITE:
4554 case KEY_NEED_LINK:
4555 case KEY_NEED_SETATTR:
4556 request |= MAY_WRITE;
4557 break;
4558 case KEY_NEED_UNSPECIFIED:
4559 case KEY_NEED_UNLINK:
4560 case KEY_SYSADMIN_OVERRIDE:
4561 case KEY_AUTHTOKEN_OVERRIDE:
4562 case KEY_DEFER_PERM_CHECK:
4563 return 0;
4564 default:
4565 return -EINVAL;
4566 }
4567
4568 keyp = key_ref_to_ptr(key_ref);
4569 if (keyp == NULL)
4570 return -EINVAL;
4571 /*
4572 * If the key hasn't been initialized give it access so that
4573 * it may do so.
4574 */
4575 blob = smack_key(keyp);
4576 skp = *blob;
4577 if (skp == NULL)
4578 return 0;
4579 /*
4580 * This should not occur
4581 */
4582 if (tkp == NULL)
4583 return -EACCES;
4584
4585 if (smack_privileged(CAP_MAC_OVERRIDE))
4586 return 0;
4587
4588#ifdef CONFIG_AUDIT
4589 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY);
4590 ad.a.u.key_struct.key = keyp->serial;
4591 ad.a.u.key_struct.key_desc = keyp->description;
4592#endif
4593 rc = smk_access(tkp, skp, request, &ad);
4594 rc = smk_bu_note("key access", tkp, skp, request, rc);
4595 return rc;
4596}
4597
4598/*
4599 * smack_key_getsecurity - Smack label tagging the key
4600 * @key points to the key to be queried
4601 * @_buffer points to a pointer that should be set to point to the
4602 * resulting string (if no label or an error occurs).
4603 * Return the length of the string (including terminating NUL) or -ve if
4604 * an error.
4605 * May also return 0 (and a NULL buffer pointer) if there is no label.
4606 */
4607static int smack_key_getsecurity(struct key *key, char **_buffer)
4608{
4609 struct smack_known **blob = smack_key(key);
4610 struct smack_known *skp = *blob;
4611 size_t length;
4612 char *copy;
4613
4614 if (skp == NULL) {
4615 *_buffer = NULL;
4616 return 0;
4617 }
4618
4619 copy = kstrdup(skp->smk_known, GFP_KERNEL);
4620 if (copy == NULL)
4621 return -ENOMEM;
4622 length = strlen(copy) + 1;
4623
4624 *_buffer = copy;
4625 return length;
4626}
4627
4628
4629#ifdef CONFIG_KEY_NOTIFICATIONS
4630/**
4631 * smack_watch_key - Smack access to watch a key for notifications.
4632 * @key: The key to be watched
4633 *
4634 * Return 0 if the @watch->cred has permission to read from the key object and
4635 * an error otherwise.
4636 */
4637static int smack_watch_key(struct key *key)
4638{
4639 struct smk_audit_info ad;
4640 struct smack_known *tkp = smk_of_current();
4641 struct smack_known **blob = smack_key(key);
4642 int rc;
4643
4644 /*
4645 * This should not occur
4646 */
4647 if (tkp == NULL)
4648 return -EACCES;
4649
4650 if (smack_privileged_cred(CAP_MAC_OVERRIDE, current_cred()))
4651 return 0;
4652
4653#ifdef CONFIG_AUDIT
4654 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY);
4655 ad.a.u.key_struct.key = key->serial;
4656 ad.a.u.key_struct.key_desc = key->description;
4657#endif
4658 rc = smk_access(tkp, *blob, MAY_READ, &ad);
4659 rc = smk_bu_note("key watch", tkp, *blob, MAY_READ, rc);
4660 return rc;
4661}
4662#endif /* CONFIG_KEY_NOTIFICATIONS */
4663#endif /* CONFIG_KEYS */
4664
4665#ifdef CONFIG_WATCH_QUEUE
4666/**
4667 * smack_post_notification - Smack access to post a notification to a queue
4668 * @w_cred: The credentials of the watcher.
4669 * @cred: The credentials of the event source (may be NULL).
4670 * @n: The notification message to be posted.
4671 */
4672static int smack_post_notification(const struct cred *w_cred,
4673 const struct cred *cred,
4674 struct watch_notification *n)
4675{
4676 struct smk_audit_info ad;
4677 struct smack_known *subj, *obj;
4678 int rc;
4679
4680 /* Always let maintenance notifications through. */
4681 if (n->type == WATCH_TYPE_META)
4682 return 0;
4683
4684 if (!cred)
4685 return 0;
4686 subj = smk_of_task(smack_cred(cred));
4687 obj = smk_of_task(smack_cred(w_cred));
4688
4689 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NOTIFICATION);
4690 rc = smk_access(subj, obj, MAY_WRITE, &ad);
4691 rc = smk_bu_note("notification", subj, obj, MAY_WRITE, rc);
4692 return rc;
4693}
4694#endif /* CONFIG_WATCH_QUEUE */
4695
4696/*
4697 * Smack Audit hooks
4698 *
4699 * Audit requires a unique representation of each Smack specific
4700 * rule. This unique representation is used to distinguish the
4701 * object to be audited from remaining kernel objects and also
4702 * works as a glue between the audit hooks.
4703 *
4704 * Since repository entries are added but never deleted, we'll use
4705 * the smack_known label address related to the given audit rule as
4706 * the needed unique representation. This also better fits the smack
4707 * model where nearly everything is a label.
4708 */
4709#ifdef CONFIG_AUDIT
4710
4711/**
4712 * smack_audit_rule_init - Initialize a smack audit rule
4713 * @field: audit rule fields given from user-space (audit.h)
4714 * @op: required testing operator (=, !=, >, <, ...)
4715 * @rulestr: smack label to be audited
4716 * @vrule: pointer to save our own audit rule representation
4717 * @gfp: type of the memory for the allocation
4718 *
4719 * Prepare to audit cases where (@field @op @rulestr) is true.
4720 * The label to be audited is created if necessay.
4721 */
4722static int smack_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule,
4723 gfp_t gfp)
4724{
4725 struct smack_known *skp;
4726 char **rule = (char **)vrule;
4727 *rule = NULL;
4728
4729 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
4730 return -EINVAL;
4731
4732 if (op != Audit_equal && op != Audit_not_equal)
4733 return -EINVAL;
4734
4735 skp = smk_import_entry(rulestr, 0);
4736 if (IS_ERR(skp))
4737 return PTR_ERR(skp);
4738
4739 *rule = skp->smk_known;
4740
4741 return 0;
4742}
4743
4744/**
4745 * smack_audit_rule_known - Distinguish Smack audit rules
4746 * @krule: rule of interest, in Audit kernel representation format
4747 *
4748 * This is used to filter Smack rules from remaining Audit ones.
4749 * If it's proved that this rule belongs to us, the
4750 * audit_rule_match hook will be called to do the final judgement.
4751 */
4752static int smack_audit_rule_known(struct audit_krule *krule)
4753{
4754 struct audit_field *f;
4755 int i;
4756
4757 for (i = 0; i < krule->field_count; i++) {
4758 f = &krule->fields[i];
4759
4760 if (f->type == AUDIT_SUBJ_USER || f->type == AUDIT_OBJ_USER)
4761 return 1;
4762 }
4763
4764 return 0;
4765}
4766
4767/**
4768 * smack_audit_rule_match - Audit given object ?
4769 * @prop: security id for identifying the object to test
4770 * @field: audit rule flags given from user-space
4771 * @op: required testing operator
4772 * @vrule: smack internal rule presentation
4773 *
4774 * The core Audit hook. It's used to take the decision of
4775 * whether to audit or not to audit a given object.
4776 */
4777static int smack_audit_rule_match(struct lsm_prop *prop, u32 field, u32 op,
4778 void *vrule)
4779{
4780 struct smack_known *skp = prop->smack.skp;
4781 char *rule = vrule;
4782
4783 if (unlikely(!rule)) {
4784 WARN_ONCE(1, "Smack: missing rule\n");
4785 return -ENOENT;
4786 }
4787
4788 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
4789 return 0;
4790
4791 /*
4792 * No need to do string comparisons. If a match occurs,
4793 * both pointers will point to the same smack_known
4794 * label.
4795 */
4796 if (op == Audit_equal)
4797 return (rule == skp->smk_known);
4798 if (op == Audit_not_equal)
4799 return (rule != skp->smk_known);
4800
4801 return 0;
4802}
4803
4804/*
4805 * There is no need for a smack_audit_rule_free hook.
4806 * No memory was allocated.
4807 */
4808
4809#endif /* CONFIG_AUDIT */
4810
4811/**
4812 * smack_ismaclabel - check if xattr @name references a smack MAC label
4813 * @name: Full xattr name to check.
4814 */
4815static int smack_ismaclabel(const char *name)
4816{
4817 return (strcmp(name, XATTR_SMACK_SUFFIX) == 0);
4818}
4819
4820/**
4821 * smack_secid_to_secctx - return the smack label for a secid
4822 * @secid: incoming integer
4823 * @secdata: destination
4824 * @seclen: how long it is
4825 *
4826 * Exists for networking code.
4827 */
4828static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
4829{
4830 struct smack_known *skp = smack_from_secid(secid);
4831
4832 if (secdata)
4833 *secdata = skp->smk_known;
4834 *seclen = strlen(skp->smk_known);
4835 return 0;
4836}
4837
4838/**
4839 * smack_lsmprop_to_secctx - return the smack label
4840 * @prop: includes incoming Smack data
4841 * @secdata: destination
4842 * @seclen: how long it is
4843 *
4844 * Exists for audit code.
4845 */
4846static int smack_lsmprop_to_secctx(struct lsm_prop *prop, char **secdata,
4847 u32 *seclen)
4848{
4849 struct smack_known *skp = prop->smack.skp;
4850
4851 if (secdata)
4852 *secdata = skp->smk_known;
4853 *seclen = strlen(skp->smk_known);
4854 return 0;
4855}
4856
4857/**
4858 * smack_secctx_to_secid - return the secid for a smack label
4859 * @secdata: smack label
4860 * @seclen: how long result is
4861 * @secid: outgoing integer
4862 *
4863 * Exists for audit and networking code.
4864 */
4865static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
4866{
4867 struct smack_known *skp = smk_find_entry(secdata);
4868
4869 if (skp)
4870 *secid = skp->smk_secid;
4871 else
4872 *secid = 0;
4873 return 0;
4874}
4875
4876/*
4877 * There used to be a smack_release_secctx hook
4878 * that did nothing back when hooks were in a vector.
4879 * Now that there's a list such a hook adds cost.
4880 */
4881
4882static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
4883{
4884 return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx,
4885 ctxlen, 0);
4886}
4887
4888static int smack_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
4889{
4890 return __vfs_setxattr_locked(&nop_mnt_idmap, dentry, XATTR_NAME_SMACK,
4891 ctx, ctxlen, 0, NULL);
4892}
4893
4894static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
4895{
4896 struct smack_known *skp = smk_of_inode(inode);
4897
4898 *ctx = skp->smk_known;
4899 *ctxlen = strlen(skp->smk_known);
4900 return 0;
4901}
4902
4903static int smack_inode_copy_up(struct dentry *dentry, struct cred **new)
4904{
4905
4906 struct task_smack *tsp;
4907 struct smack_known *skp;
4908 struct inode_smack *isp;
4909 struct cred *new_creds = *new;
4910
4911 if (new_creds == NULL) {
4912 new_creds = prepare_creds();
4913 if (new_creds == NULL)
4914 return -ENOMEM;
4915 }
4916
4917 tsp = smack_cred(new_creds);
4918
4919 /*
4920 * Get label from overlay inode and set it in create_sid
4921 */
4922 isp = smack_inode(d_inode(dentry));
4923 skp = isp->smk_inode;
4924 tsp->smk_task = skp;
4925 *new = new_creds;
4926 return 0;
4927}
4928
4929static int smack_inode_copy_up_xattr(struct dentry *src, const char *name)
4930{
4931 /*
4932 * Return -ECANCELED if this is the smack access Smack attribute.
4933 */
4934 if (!strcmp(name, XATTR_NAME_SMACK))
4935 return -ECANCELED;
4936
4937 return -EOPNOTSUPP;
4938}
4939
4940static int smack_dentry_create_files_as(struct dentry *dentry, int mode,
4941 struct qstr *name,
4942 const struct cred *old,
4943 struct cred *new)
4944{
4945 struct task_smack *otsp = smack_cred(old);
4946 struct task_smack *ntsp = smack_cred(new);
4947 struct inode_smack *isp;
4948 int may;
4949
4950 /*
4951 * Use the process credential unless all of
4952 * the transmuting criteria are met
4953 */
4954 ntsp->smk_task = otsp->smk_task;
4955
4956 /*
4957 * the attribute of the containing directory
4958 */
4959 isp = smack_inode(d_inode(dentry->d_parent));
4960
4961 if (isp->smk_flags & SMK_INODE_TRANSMUTE) {
4962 rcu_read_lock();
4963 may = smk_access_entry(otsp->smk_task->smk_known,
4964 isp->smk_inode->smk_known,
4965 &otsp->smk_task->smk_rules);
4966 rcu_read_unlock();
4967
4968 /*
4969 * If the directory is transmuting and the rule
4970 * providing access is transmuting use the containing
4971 * directory label instead of the process label.
4972 */
4973 if (may > 0 && (may & MAY_TRANSMUTE)) {
4974 ntsp->smk_task = isp->smk_inode;
4975 ntsp->smk_transmuted = ntsp->smk_task;
4976 }
4977 }
4978 return 0;
4979}
4980
4981#ifdef CONFIG_IO_URING
4982/**
4983 * smack_uring_override_creds - Is io_uring cred override allowed?
4984 * @new: the target creds
4985 *
4986 * Check to see if the current task is allowed to override it's credentials
4987 * to service an io_uring operation.
4988 */
4989static int smack_uring_override_creds(const struct cred *new)
4990{
4991 struct task_smack *tsp = smack_cred(current_cred());
4992 struct task_smack *nsp = smack_cred(new);
4993
4994 /*
4995 * Allow the degenerate case where the new Smack value is
4996 * the same as the current Smack value.
4997 */
4998 if (tsp->smk_task == nsp->smk_task)
4999 return 0;
5000
5001 if (smack_privileged_cred(CAP_MAC_OVERRIDE, current_cred()))
5002 return 0;
5003
5004 return -EPERM;
5005}
5006
5007/**
5008 * smack_uring_sqpoll - check if a io_uring polling thread can be created
5009 *
5010 * Check to see if the current task is allowed to create a new io_uring
5011 * kernel polling thread.
5012 */
5013static int smack_uring_sqpoll(void)
5014{
5015 if (smack_privileged_cred(CAP_MAC_ADMIN, current_cred()))
5016 return 0;
5017
5018 return -EPERM;
5019}
5020
5021/**
5022 * smack_uring_cmd - check on file operations for io_uring
5023 * @ioucmd: the command in question
5024 *
5025 * Make a best guess about whether a io_uring "command" should
5026 * be allowed. Use the same logic used for determining if the
5027 * file could be opened for read in the absence of better criteria.
5028 */
5029static int smack_uring_cmd(struct io_uring_cmd *ioucmd)
5030{
5031 struct file *file = ioucmd->file;
5032 struct smk_audit_info ad;
5033 struct task_smack *tsp;
5034 struct inode *inode;
5035 int rc;
5036
5037 if (!file)
5038 return -EINVAL;
5039
5040 tsp = smack_cred(file->f_cred);
5041 inode = file_inode(file);
5042
5043 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
5044 smk_ad_setfield_u_fs_path(&ad, file->f_path);
5045 rc = smk_tskacc(tsp, smk_of_inode(inode), MAY_READ, &ad);
5046 rc = smk_bu_credfile(file->f_cred, file, MAY_READ, rc);
5047
5048 return rc;
5049}
5050
5051#endif /* CONFIG_IO_URING */
5052
5053struct lsm_blob_sizes smack_blob_sizes __ro_after_init = {
5054 .lbs_cred = sizeof(struct task_smack),
5055 .lbs_file = sizeof(struct smack_known *),
5056 .lbs_inode = sizeof(struct inode_smack),
5057 .lbs_ipc = sizeof(struct smack_known *),
5058 .lbs_key = sizeof(struct smack_known *),
5059 .lbs_msg_msg = sizeof(struct smack_known *),
5060 .lbs_sock = sizeof(struct socket_smack),
5061 .lbs_superblock = sizeof(struct superblock_smack),
5062 .lbs_xattr_count = SMACK_INODE_INIT_XATTRS,
5063};
5064
5065static const struct lsm_id smack_lsmid = {
5066 .name = "smack",
5067 .id = LSM_ID_SMACK,
5068};
5069
5070static struct security_hook_list smack_hooks[] __ro_after_init = {
5071 LSM_HOOK_INIT(ptrace_access_check, smack_ptrace_access_check),
5072 LSM_HOOK_INIT(ptrace_traceme, smack_ptrace_traceme),
5073 LSM_HOOK_INIT(syslog, smack_syslog),
5074
5075 LSM_HOOK_INIT(fs_context_submount, smack_fs_context_submount),
5076 LSM_HOOK_INIT(fs_context_dup, smack_fs_context_dup),
5077 LSM_HOOK_INIT(fs_context_parse_param, smack_fs_context_parse_param),
5078
5079 LSM_HOOK_INIT(sb_alloc_security, smack_sb_alloc_security),
5080 LSM_HOOK_INIT(sb_free_mnt_opts, smack_free_mnt_opts),
5081 LSM_HOOK_INIT(sb_eat_lsm_opts, smack_sb_eat_lsm_opts),
5082 LSM_HOOK_INIT(sb_statfs, smack_sb_statfs),
5083 LSM_HOOK_INIT(sb_set_mnt_opts, smack_set_mnt_opts),
5084
5085 LSM_HOOK_INIT(bprm_creds_for_exec, smack_bprm_creds_for_exec),
5086
5087 LSM_HOOK_INIT(inode_alloc_security, smack_inode_alloc_security),
5088 LSM_HOOK_INIT(inode_init_security, smack_inode_init_security),
5089 LSM_HOOK_INIT(inode_link, smack_inode_link),
5090 LSM_HOOK_INIT(inode_unlink, smack_inode_unlink),
5091 LSM_HOOK_INIT(inode_rmdir, smack_inode_rmdir),
5092 LSM_HOOK_INIT(inode_rename, smack_inode_rename),
5093 LSM_HOOK_INIT(inode_permission, smack_inode_permission),
5094 LSM_HOOK_INIT(inode_setattr, smack_inode_setattr),
5095 LSM_HOOK_INIT(inode_getattr, smack_inode_getattr),
5096 LSM_HOOK_INIT(inode_xattr_skipcap, smack_inode_xattr_skipcap),
5097 LSM_HOOK_INIT(inode_setxattr, smack_inode_setxattr),
5098 LSM_HOOK_INIT(inode_post_setxattr, smack_inode_post_setxattr),
5099 LSM_HOOK_INIT(inode_getxattr, smack_inode_getxattr),
5100 LSM_HOOK_INIT(inode_removexattr, smack_inode_removexattr),
5101 LSM_HOOK_INIT(inode_set_acl, smack_inode_set_acl),
5102 LSM_HOOK_INIT(inode_get_acl, smack_inode_get_acl),
5103 LSM_HOOK_INIT(inode_remove_acl, smack_inode_remove_acl),
5104 LSM_HOOK_INIT(inode_getsecurity, smack_inode_getsecurity),
5105 LSM_HOOK_INIT(inode_setsecurity, smack_inode_setsecurity),
5106 LSM_HOOK_INIT(inode_listsecurity, smack_inode_listsecurity),
5107 LSM_HOOK_INIT(inode_getlsmprop, smack_inode_getlsmprop),
5108
5109 LSM_HOOK_INIT(file_alloc_security, smack_file_alloc_security),
5110 LSM_HOOK_INIT(file_ioctl, smack_file_ioctl),
5111 LSM_HOOK_INIT(file_ioctl_compat, smack_file_ioctl),
5112 LSM_HOOK_INIT(file_lock, smack_file_lock),
5113 LSM_HOOK_INIT(file_fcntl, smack_file_fcntl),
5114 LSM_HOOK_INIT(mmap_file, smack_mmap_file),
5115 LSM_HOOK_INIT(mmap_addr, cap_mmap_addr),
5116 LSM_HOOK_INIT(file_set_fowner, smack_file_set_fowner),
5117 LSM_HOOK_INIT(file_send_sigiotask, smack_file_send_sigiotask),
5118 LSM_HOOK_INIT(file_receive, smack_file_receive),
5119
5120 LSM_HOOK_INIT(file_open, smack_file_open),
5121
5122 LSM_HOOK_INIT(cred_alloc_blank, smack_cred_alloc_blank),
5123 LSM_HOOK_INIT(cred_free, smack_cred_free),
5124 LSM_HOOK_INIT(cred_prepare, smack_cred_prepare),
5125 LSM_HOOK_INIT(cred_transfer, smack_cred_transfer),
5126 LSM_HOOK_INIT(cred_getsecid, smack_cred_getsecid),
5127 LSM_HOOK_INIT(cred_getlsmprop, smack_cred_getlsmprop),
5128 LSM_HOOK_INIT(kernel_act_as, smack_kernel_act_as),
5129 LSM_HOOK_INIT(kernel_create_files_as, smack_kernel_create_files_as),
5130 LSM_HOOK_INIT(task_setpgid, smack_task_setpgid),
5131 LSM_HOOK_INIT(task_getpgid, smack_task_getpgid),
5132 LSM_HOOK_INIT(task_getsid, smack_task_getsid),
5133 LSM_HOOK_INIT(current_getlsmprop_subj, smack_current_getlsmprop_subj),
5134 LSM_HOOK_INIT(task_getlsmprop_obj, smack_task_getlsmprop_obj),
5135 LSM_HOOK_INIT(task_setnice, smack_task_setnice),
5136 LSM_HOOK_INIT(task_setioprio, smack_task_setioprio),
5137 LSM_HOOK_INIT(task_getioprio, smack_task_getioprio),
5138 LSM_HOOK_INIT(task_setscheduler, smack_task_setscheduler),
5139 LSM_HOOK_INIT(task_getscheduler, smack_task_getscheduler),
5140 LSM_HOOK_INIT(task_movememory, smack_task_movememory),
5141 LSM_HOOK_INIT(task_kill, smack_task_kill),
5142 LSM_HOOK_INIT(task_to_inode, smack_task_to_inode),
5143
5144 LSM_HOOK_INIT(ipc_permission, smack_ipc_permission),
5145 LSM_HOOK_INIT(ipc_getlsmprop, smack_ipc_getlsmprop),
5146
5147 LSM_HOOK_INIT(msg_msg_alloc_security, smack_msg_msg_alloc_security),
5148
5149 LSM_HOOK_INIT(msg_queue_alloc_security, smack_ipc_alloc_security),
5150 LSM_HOOK_INIT(msg_queue_associate, smack_msg_queue_associate),
5151 LSM_HOOK_INIT(msg_queue_msgctl, smack_msg_queue_msgctl),
5152 LSM_HOOK_INIT(msg_queue_msgsnd, smack_msg_queue_msgsnd),
5153 LSM_HOOK_INIT(msg_queue_msgrcv, smack_msg_queue_msgrcv),
5154
5155 LSM_HOOK_INIT(shm_alloc_security, smack_ipc_alloc_security),
5156 LSM_HOOK_INIT(shm_associate, smack_shm_associate),
5157 LSM_HOOK_INIT(shm_shmctl, smack_shm_shmctl),
5158 LSM_HOOK_INIT(shm_shmat, smack_shm_shmat),
5159
5160 LSM_HOOK_INIT(sem_alloc_security, smack_ipc_alloc_security),
5161 LSM_HOOK_INIT(sem_associate, smack_sem_associate),
5162 LSM_HOOK_INIT(sem_semctl, smack_sem_semctl),
5163 LSM_HOOK_INIT(sem_semop, smack_sem_semop),
5164
5165 LSM_HOOK_INIT(d_instantiate, smack_d_instantiate),
5166
5167 LSM_HOOK_INIT(getselfattr, smack_getselfattr),
5168 LSM_HOOK_INIT(setselfattr, smack_setselfattr),
5169 LSM_HOOK_INIT(getprocattr, smack_getprocattr),
5170 LSM_HOOK_INIT(setprocattr, smack_setprocattr),
5171
5172 LSM_HOOK_INIT(unix_stream_connect, smack_unix_stream_connect),
5173 LSM_HOOK_INIT(unix_may_send, smack_unix_may_send),
5174
5175 LSM_HOOK_INIT(socket_post_create, smack_socket_post_create),
5176 LSM_HOOK_INIT(socket_socketpair, smack_socket_socketpair),
5177#ifdef SMACK_IPV6_PORT_LABELING
5178 LSM_HOOK_INIT(socket_bind, smack_socket_bind),
5179#endif
5180 LSM_HOOK_INIT(socket_connect, smack_socket_connect),
5181 LSM_HOOK_INIT(socket_sendmsg, smack_socket_sendmsg),
5182 LSM_HOOK_INIT(socket_sock_rcv_skb, smack_socket_sock_rcv_skb),
5183 LSM_HOOK_INIT(socket_getpeersec_stream, smack_socket_getpeersec_stream),
5184 LSM_HOOK_INIT(socket_getpeersec_dgram, smack_socket_getpeersec_dgram),
5185 LSM_HOOK_INIT(sk_alloc_security, smack_sk_alloc_security),
5186#ifdef SMACK_IPV6_PORT_LABELING
5187 LSM_HOOK_INIT(sk_free_security, smack_sk_free_security),
5188#endif
5189 LSM_HOOK_INIT(sk_clone_security, smack_sk_clone_security),
5190 LSM_HOOK_INIT(sock_graft, smack_sock_graft),
5191 LSM_HOOK_INIT(inet_conn_request, smack_inet_conn_request),
5192 LSM_HOOK_INIT(inet_csk_clone, smack_inet_csk_clone),
5193
5194 /* key management security hooks */
5195#ifdef CONFIG_KEYS
5196 LSM_HOOK_INIT(key_alloc, smack_key_alloc),
5197 LSM_HOOK_INIT(key_permission, smack_key_permission),
5198 LSM_HOOK_INIT(key_getsecurity, smack_key_getsecurity),
5199#ifdef CONFIG_KEY_NOTIFICATIONS
5200 LSM_HOOK_INIT(watch_key, smack_watch_key),
5201#endif
5202#endif /* CONFIG_KEYS */
5203
5204#ifdef CONFIG_WATCH_QUEUE
5205 LSM_HOOK_INIT(post_notification, smack_post_notification),
5206#endif
5207
5208 /* Audit hooks */
5209#ifdef CONFIG_AUDIT
5210 LSM_HOOK_INIT(audit_rule_init, smack_audit_rule_init),
5211 LSM_HOOK_INIT(audit_rule_known, smack_audit_rule_known),
5212 LSM_HOOK_INIT(audit_rule_match, smack_audit_rule_match),
5213#endif /* CONFIG_AUDIT */
5214
5215 LSM_HOOK_INIT(ismaclabel, smack_ismaclabel),
5216 LSM_HOOK_INIT(secid_to_secctx, smack_secid_to_secctx),
5217 LSM_HOOK_INIT(lsmprop_to_secctx, smack_lsmprop_to_secctx),
5218 LSM_HOOK_INIT(secctx_to_secid, smack_secctx_to_secid),
5219 LSM_HOOK_INIT(inode_notifysecctx, smack_inode_notifysecctx),
5220 LSM_HOOK_INIT(inode_setsecctx, smack_inode_setsecctx),
5221 LSM_HOOK_INIT(inode_getsecctx, smack_inode_getsecctx),
5222 LSM_HOOK_INIT(inode_copy_up, smack_inode_copy_up),
5223 LSM_HOOK_INIT(inode_copy_up_xattr, smack_inode_copy_up_xattr),
5224 LSM_HOOK_INIT(dentry_create_files_as, smack_dentry_create_files_as),
5225#ifdef CONFIG_IO_URING
5226 LSM_HOOK_INIT(uring_override_creds, smack_uring_override_creds),
5227 LSM_HOOK_INIT(uring_sqpoll, smack_uring_sqpoll),
5228 LSM_HOOK_INIT(uring_cmd, smack_uring_cmd),
5229#endif
5230};
5231
5232
5233static __init void init_smack_known_list(void)
5234{
5235 /*
5236 * Initialize rule list locks
5237 */
5238 mutex_init(&smack_known_huh.smk_rules_lock);
5239 mutex_init(&smack_known_hat.smk_rules_lock);
5240 mutex_init(&smack_known_floor.smk_rules_lock);
5241 mutex_init(&smack_known_star.smk_rules_lock);
5242 mutex_init(&smack_known_web.smk_rules_lock);
5243 /*
5244 * Initialize rule lists
5245 */
5246 INIT_LIST_HEAD(&smack_known_huh.smk_rules);
5247 INIT_LIST_HEAD(&smack_known_hat.smk_rules);
5248 INIT_LIST_HEAD(&smack_known_star.smk_rules);
5249 INIT_LIST_HEAD(&smack_known_floor.smk_rules);
5250 INIT_LIST_HEAD(&smack_known_web.smk_rules);
5251 /*
5252 * Create the known labels list
5253 */
5254 smk_insert_entry(&smack_known_huh);
5255 smk_insert_entry(&smack_known_hat);
5256 smk_insert_entry(&smack_known_star);
5257 smk_insert_entry(&smack_known_floor);
5258 smk_insert_entry(&smack_known_web);
5259}
5260
5261/**
5262 * smack_init - initialize the smack system
5263 *
5264 * Returns 0 on success, -ENOMEM is there's no memory
5265 */
5266static __init int smack_init(void)
5267{
5268 struct cred *cred = (struct cred *) current->cred;
5269 struct task_smack *tsp;
5270
5271 smack_rule_cache = KMEM_CACHE(smack_rule, 0);
5272 if (!smack_rule_cache)
5273 return -ENOMEM;
5274
5275 /*
5276 * Set the security state for the initial task.
5277 */
5278 tsp = smack_cred(cred);
5279 init_task_smack(tsp, &smack_known_floor, &smack_known_floor);
5280
5281 /*
5282 * Register with LSM
5283 */
5284 security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks), &smack_lsmid);
5285 smack_enabled = 1;
5286
5287 pr_info("Smack: Initializing.\n");
5288#ifdef CONFIG_SECURITY_SMACK_NETFILTER
5289 pr_info("Smack: Netfilter enabled.\n");
5290#endif
5291#ifdef SMACK_IPV6_PORT_LABELING
5292 pr_info("Smack: IPv6 port labeling enabled.\n");
5293#endif
5294#ifdef SMACK_IPV6_SECMARK_LABELING
5295 pr_info("Smack: IPv6 Netfilter enabled.\n");
5296#endif
5297
5298 /* initialize the smack_known_list */
5299 init_smack_known_list();
5300
5301 return 0;
5302}
5303
5304/*
5305 * Smack requires early initialization in order to label
5306 * all processes and objects when they are created.
5307 */
5308DEFINE_LSM(smack) = {
5309 .name = "smack",
5310 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
5311 .blobs = &smack_blob_sizes,
5312 .init = smack_init,
5313};