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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 smack_known *skp = smk_of_task(tsp);
998 struct smack_known *isp = smk_of_inode(inode);
999 struct smack_known *dsp = smk_of_inode(dir);
1000 struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count);
1001 int may;
1002
1003 if (xattr) {
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 = dsp;
1034 xattr_transmute = lsm_get_xattr_slot(xattrs,
1035 xattr_count);
1036 if (xattr_transmute) {
1037 xattr_transmute->value = kmemdup(TRANS_TRUE,
1038 TRANS_TRUE_SIZE,
1039 GFP_NOFS);
1040 if (!xattr_transmute->value)
1041 return -ENOMEM;
1042
1043 xattr_transmute->value_len = TRANS_TRUE_SIZE;
1044 xattr_transmute->name = XATTR_SMACK_TRANSMUTE;
1045 }
1046 }
1047
1048 xattr->value = kstrdup(isp->smk_known, GFP_NOFS);
1049 if (!xattr->value)
1050 return -ENOMEM;
1051
1052 xattr->value_len = strlen(isp->smk_known);
1053 xattr->name = XATTR_SMACK_SUFFIX;
1054 }
1055
1056 return 0;
1057}
1058
1059/**
1060 * smack_inode_link - Smack check on link
1061 * @old_dentry: the existing object
1062 * @dir: unused
1063 * @new_dentry: the new object
1064 *
1065 * Returns 0 if access is permitted, an error code otherwise
1066 */
1067static int smack_inode_link(struct dentry *old_dentry, struct inode *dir,
1068 struct dentry *new_dentry)
1069{
1070 struct smack_known *isp;
1071 struct smk_audit_info ad;
1072 int rc;
1073
1074 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1075 smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
1076
1077 isp = smk_of_inode(d_backing_inode(old_dentry));
1078 rc = smk_curacc(isp, MAY_WRITE, &ad);
1079 rc = smk_bu_inode(d_backing_inode(old_dentry), MAY_WRITE, rc);
1080
1081 if (rc == 0 && d_is_positive(new_dentry)) {
1082 isp = smk_of_inode(d_backing_inode(new_dentry));
1083 smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
1084 rc = smk_curacc(isp, MAY_WRITE, &ad);
1085 rc = smk_bu_inode(d_backing_inode(new_dentry), MAY_WRITE, rc);
1086 }
1087
1088 return rc;
1089}
1090
1091/**
1092 * smack_inode_unlink - Smack check on inode deletion
1093 * @dir: containing directory object
1094 * @dentry: file to unlink
1095 *
1096 * Returns 0 if current can write the containing directory
1097 * and the object, error code otherwise
1098 */
1099static int smack_inode_unlink(struct inode *dir, struct dentry *dentry)
1100{
1101 struct inode *ip = d_backing_inode(dentry);
1102 struct smk_audit_info ad;
1103 int rc;
1104
1105 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1106 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1107
1108 /*
1109 * You need write access to the thing you're unlinking
1110 */
1111 rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad);
1112 rc = smk_bu_inode(ip, MAY_WRITE, rc);
1113 if (rc == 0) {
1114 /*
1115 * You also need write access to the containing directory
1116 */
1117 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
1118 smk_ad_setfield_u_fs_inode(&ad, dir);
1119 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
1120 rc = smk_bu_inode(dir, MAY_WRITE, rc);
1121 }
1122 return rc;
1123}
1124
1125/**
1126 * smack_inode_rmdir - Smack check on directory deletion
1127 * @dir: containing directory object
1128 * @dentry: directory to unlink
1129 *
1130 * Returns 0 if current can write the containing directory
1131 * and the directory, error code otherwise
1132 */
1133static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry)
1134{
1135 struct smk_audit_info ad;
1136 int rc;
1137
1138 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1139 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1140
1141 /*
1142 * You need write access to the thing you're removing
1143 */
1144 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1145 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1146 if (rc == 0) {
1147 /*
1148 * You also need write access to the containing directory
1149 */
1150 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
1151 smk_ad_setfield_u_fs_inode(&ad, dir);
1152 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
1153 rc = smk_bu_inode(dir, MAY_WRITE, rc);
1154 }
1155
1156 return rc;
1157}
1158
1159/**
1160 * smack_inode_rename - Smack check on rename
1161 * @old_inode: unused
1162 * @old_dentry: the old object
1163 * @new_inode: unused
1164 * @new_dentry: the new object
1165 *
1166 * Read and write access is required on both the old and
1167 * new directories.
1168 *
1169 * Returns 0 if access is permitted, an error code otherwise
1170 */
1171static int smack_inode_rename(struct inode *old_inode,
1172 struct dentry *old_dentry,
1173 struct inode *new_inode,
1174 struct dentry *new_dentry)
1175{
1176 int rc;
1177 struct smack_known *isp;
1178 struct smk_audit_info ad;
1179
1180 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1181 smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
1182
1183 isp = smk_of_inode(d_backing_inode(old_dentry));
1184 rc = smk_curacc(isp, MAY_READWRITE, &ad);
1185 rc = smk_bu_inode(d_backing_inode(old_dentry), MAY_READWRITE, rc);
1186
1187 if (rc == 0 && d_is_positive(new_dentry)) {
1188 isp = smk_of_inode(d_backing_inode(new_dentry));
1189 smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
1190 rc = smk_curacc(isp, MAY_READWRITE, &ad);
1191 rc = smk_bu_inode(d_backing_inode(new_dentry), MAY_READWRITE, rc);
1192 }
1193 return rc;
1194}
1195
1196/**
1197 * smack_inode_permission - Smack version of permission()
1198 * @inode: the inode in question
1199 * @mask: the access requested
1200 *
1201 * This is the important Smack hook.
1202 *
1203 * Returns 0 if access is permitted, an error code otherwise
1204 */
1205static int smack_inode_permission(struct inode *inode, int mask)
1206{
1207 struct superblock_smack *sbsp = smack_superblock(inode->i_sb);
1208 struct smk_audit_info ad;
1209 int no_block = mask & MAY_NOT_BLOCK;
1210 int rc;
1211
1212 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
1213 /*
1214 * No permission to check. Existence test. Yup, it's there.
1215 */
1216 if (mask == 0)
1217 return 0;
1218
1219 if (sbsp->smk_flags & SMK_SB_UNTRUSTED) {
1220 if (smk_of_inode(inode) != sbsp->smk_root)
1221 return -EACCES;
1222 }
1223
1224 /* May be droppable after audit */
1225 if (no_block)
1226 return -ECHILD;
1227 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
1228 smk_ad_setfield_u_fs_inode(&ad, inode);
1229 rc = smk_curacc(smk_of_inode(inode), mask, &ad);
1230 rc = smk_bu_inode(inode, mask, rc);
1231 return rc;
1232}
1233
1234/**
1235 * smack_inode_setattr - Smack check for setting attributes
1236 * @dentry: the object
1237 * @iattr: for the force flag
1238 *
1239 * Returns 0 if access is permitted, an error code otherwise
1240 */
1241static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr)
1242{
1243 struct smk_audit_info ad;
1244 int rc;
1245
1246 /*
1247 * Need to allow for clearing the setuid bit.
1248 */
1249 if (iattr->ia_valid & ATTR_FORCE)
1250 return 0;
1251 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1252 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1253
1254 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1255 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1256 return rc;
1257}
1258
1259/**
1260 * smack_inode_getattr - Smack check for getting attributes
1261 * @path: path to extract the info from
1262 *
1263 * Returns 0 if access is permitted, an error code otherwise
1264 */
1265static int smack_inode_getattr(const struct path *path)
1266{
1267 struct smk_audit_info ad;
1268 struct inode *inode = d_backing_inode(path->dentry);
1269 int rc;
1270
1271 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1272 smk_ad_setfield_u_fs_path(&ad, *path);
1273 rc = smk_curacc(smk_of_inode(inode), MAY_READ, &ad);
1274 rc = smk_bu_inode(inode, MAY_READ, rc);
1275 return rc;
1276}
1277
1278/**
1279 * smack_inode_setxattr - Smack check for setting xattrs
1280 * @idmap: idmap of the mount
1281 * @dentry: the object
1282 * @name: name of the attribute
1283 * @value: value of the attribute
1284 * @size: size of the value
1285 * @flags: unused
1286 *
1287 * This protects the Smack attribute explicitly.
1288 *
1289 * Returns 0 if access is permitted, an error code otherwise
1290 */
1291static int smack_inode_setxattr(struct mnt_idmap *idmap,
1292 struct dentry *dentry, const char *name,
1293 const void *value, size_t size, int flags)
1294{
1295 struct smk_audit_info ad;
1296 struct smack_known *skp;
1297 int check_priv = 0;
1298 int check_import = 0;
1299 int check_star = 0;
1300 int rc = 0;
1301
1302 /*
1303 * Check label validity here so import won't fail in post_setxattr
1304 */
1305 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
1306 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
1307 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) {
1308 check_priv = 1;
1309 check_import = 1;
1310 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
1311 strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1312 check_priv = 1;
1313 check_import = 1;
1314 check_star = 1;
1315 } else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
1316 check_priv = 1;
1317 if (size != TRANS_TRUE_SIZE ||
1318 strncmp(value, TRANS_TRUE, TRANS_TRUE_SIZE) != 0)
1319 rc = -EINVAL;
1320 } else
1321 rc = cap_inode_setxattr(dentry, name, value, size, flags);
1322
1323 if (check_priv && !smack_privileged(CAP_MAC_ADMIN))
1324 rc = -EPERM;
1325
1326 if (rc == 0 && check_import) {
1327 skp = size ? smk_import_entry(value, size) : NULL;
1328 if (IS_ERR(skp))
1329 rc = PTR_ERR(skp);
1330 else if (skp == NULL || (check_star &&
1331 (skp == &smack_known_star || skp == &smack_known_web)))
1332 rc = -EINVAL;
1333 }
1334
1335 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1336 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1337
1338 if (rc == 0) {
1339 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1340 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1341 }
1342
1343 return rc;
1344}
1345
1346/**
1347 * smack_inode_post_setxattr - Apply the Smack update approved above
1348 * @dentry: object
1349 * @name: attribute name
1350 * @value: attribute value
1351 * @size: attribute size
1352 * @flags: unused
1353 *
1354 * Set the pointer in the inode blob to the entry found
1355 * in the master label list.
1356 */
1357static void smack_inode_post_setxattr(struct dentry *dentry, const char *name,
1358 const void *value, size_t size, int flags)
1359{
1360 struct smack_known *skp;
1361 struct inode_smack *isp = smack_inode(d_backing_inode(dentry));
1362
1363 if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
1364 isp->smk_flags |= SMK_INODE_TRANSMUTE;
1365 return;
1366 }
1367
1368 if (strcmp(name, XATTR_NAME_SMACK) == 0) {
1369 skp = smk_import_entry(value, size);
1370 if (!IS_ERR(skp))
1371 isp->smk_inode = skp;
1372 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0) {
1373 skp = smk_import_entry(value, size);
1374 if (!IS_ERR(skp))
1375 isp->smk_task = skp;
1376 } else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1377 skp = smk_import_entry(value, size);
1378 if (!IS_ERR(skp))
1379 isp->smk_mmap = skp;
1380 }
1381
1382 return;
1383}
1384
1385/**
1386 * smack_inode_getxattr - Smack check on getxattr
1387 * @dentry: the object
1388 * @name: unused
1389 *
1390 * Returns 0 if access is permitted, an error code otherwise
1391 */
1392static int smack_inode_getxattr(struct dentry *dentry, const char *name)
1393{
1394 struct smk_audit_info ad;
1395 int rc;
1396
1397 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1398 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1399
1400 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_READ, &ad);
1401 rc = smk_bu_inode(d_backing_inode(dentry), MAY_READ, rc);
1402 return rc;
1403}
1404
1405/**
1406 * smack_inode_removexattr - Smack check on removexattr
1407 * @idmap: idmap of the mount
1408 * @dentry: the object
1409 * @name: name of the attribute
1410 *
1411 * Removing the Smack attribute requires CAP_MAC_ADMIN
1412 *
1413 * Returns 0 if access is permitted, an error code otherwise
1414 */
1415static int smack_inode_removexattr(struct mnt_idmap *idmap,
1416 struct dentry *dentry, const char *name)
1417{
1418 struct inode_smack *isp;
1419 struct smk_audit_info ad;
1420 int rc = 0;
1421
1422 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
1423 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
1424 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
1425 strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
1426 strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0 ||
1427 strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1428 if (!smack_privileged(CAP_MAC_ADMIN))
1429 rc = -EPERM;
1430 } else
1431 rc = cap_inode_removexattr(idmap, dentry, name);
1432
1433 if (rc != 0)
1434 return rc;
1435
1436 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1437 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1438
1439 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1440 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1441 if (rc != 0)
1442 return rc;
1443
1444 isp = smack_inode(d_backing_inode(dentry));
1445 /*
1446 * Don't do anything special for these.
1447 * XATTR_NAME_SMACKIPIN
1448 * XATTR_NAME_SMACKIPOUT
1449 */
1450 if (strcmp(name, XATTR_NAME_SMACK) == 0) {
1451 struct super_block *sbp = dentry->d_sb;
1452 struct superblock_smack *sbsp = smack_superblock(sbp);
1453
1454 isp->smk_inode = sbsp->smk_default;
1455 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0)
1456 isp->smk_task = NULL;
1457 else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0)
1458 isp->smk_mmap = NULL;
1459 else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0)
1460 isp->smk_flags &= ~SMK_INODE_TRANSMUTE;
1461
1462 return 0;
1463}
1464
1465/**
1466 * smack_inode_set_acl - Smack check for setting posix acls
1467 * @idmap: idmap of the mnt this request came from
1468 * @dentry: the object
1469 * @acl_name: name of the posix acl
1470 * @kacl: the posix acls
1471 *
1472 * Returns 0 if access is permitted, an error code otherwise
1473 */
1474static int smack_inode_set_acl(struct mnt_idmap *idmap,
1475 struct dentry *dentry, const char *acl_name,
1476 struct posix_acl *kacl)
1477{
1478 struct smk_audit_info ad;
1479 int rc;
1480
1481 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1482 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1483
1484 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1485 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1486 return rc;
1487}
1488
1489/**
1490 * smack_inode_get_acl - Smack check for getting posix acls
1491 * @idmap: idmap of the mnt this request came from
1492 * @dentry: the object
1493 * @acl_name: name of the posix acl
1494 *
1495 * Returns 0 if access is permitted, an error code otherwise
1496 */
1497static int smack_inode_get_acl(struct mnt_idmap *idmap,
1498 struct dentry *dentry, const char *acl_name)
1499{
1500 struct smk_audit_info ad;
1501 int rc;
1502
1503 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1504 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1505
1506 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_READ, &ad);
1507 rc = smk_bu_inode(d_backing_inode(dentry), MAY_READ, rc);
1508 return rc;
1509}
1510
1511/**
1512 * smack_inode_remove_acl - Smack check for getting posix acls
1513 * @idmap: idmap of the mnt this request came from
1514 * @dentry: the object
1515 * @acl_name: name of the posix acl
1516 *
1517 * Returns 0 if access is permitted, an error code otherwise
1518 */
1519static int smack_inode_remove_acl(struct mnt_idmap *idmap,
1520 struct dentry *dentry, const char *acl_name)
1521{
1522 struct smk_audit_info ad;
1523 int rc;
1524
1525 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1526 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1527
1528 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1529 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1530 return rc;
1531}
1532
1533/**
1534 * smack_inode_getsecurity - get smack xattrs
1535 * @idmap: idmap of the mount
1536 * @inode: the object
1537 * @name: attribute name
1538 * @buffer: where to put the result
1539 * @alloc: duplicate memory
1540 *
1541 * Returns the size of the attribute or an error code
1542 */
1543static int smack_inode_getsecurity(struct mnt_idmap *idmap,
1544 struct inode *inode, const char *name,
1545 void **buffer, bool alloc)
1546{
1547 struct socket_smack *ssp;
1548 struct socket *sock;
1549 struct super_block *sbp;
1550 struct inode *ip = inode;
1551 struct smack_known *isp;
1552 struct inode_smack *ispp;
1553 size_t label_len;
1554 char *label = NULL;
1555
1556 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
1557 isp = smk_of_inode(inode);
1558 } else if (strcmp(name, XATTR_SMACK_TRANSMUTE) == 0) {
1559 ispp = smack_inode(inode);
1560 if (ispp->smk_flags & SMK_INODE_TRANSMUTE)
1561 label = TRANS_TRUE;
1562 else
1563 label = "";
1564 } else {
1565 /*
1566 * The rest of the Smack xattrs are only on sockets.
1567 */
1568 sbp = ip->i_sb;
1569 if (sbp->s_magic != SOCKFS_MAGIC)
1570 return -EOPNOTSUPP;
1571
1572 sock = SOCKET_I(ip);
1573 if (sock == NULL || sock->sk == NULL)
1574 return -EOPNOTSUPP;
1575
1576 ssp = sock->sk->sk_security;
1577
1578 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
1579 isp = ssp->smk_in;
1580 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0)
1581 isp = ssp->smk_out;
1582 else
1583 return -EOPNOTSUPP;
1584 }
1585
1586 if (!label)
1587 label = isp->smk_known;
1588
1589 label_len = strlen(label);
1590
1591 if (alloc) {
1592 *buffer = kstrdup(label, GFP_KERNEL);
1593 if (*buffer == NULL)
1594 return -ENOMEM;
1595 }
1596
1597 return label_len;
1598}
1599
1600
1601/**
1602 * smack_inode_listsecurity - list the Smack attributes
1603 * @inode: the object
1604 * @buffer: where they go
1605 * @buffer_size: size of buffer
1606 */
1607static int smack_inode_listsecurity(struct inode *inode, char *buffer,
1608 size_t buffer_size)
1609{
1610 int len = sizeof(XATTR_NAME_SMACK);
1611
1612 if (buffer != NULL && len <= buffer_size)
1613 memcpy(buffer, XATTR_NAME_SMACK, len);
1614
1615 return len;
1616}
1617
1618/**
1619 * smack_inode_getsecid - Extract inode's security id
1620 * @inode: inode to extract the info from
1621 * @secid: where result will be saved
1622 */
1623static void smack_inode_getsecid(struct inode *inode, u32 *secid)
1624{
1625 struct smack_known *skp = smk_of_inode(inode);
1626
1627 *secid = skp->smk_secid;
1628}
1629
1630/*
1631 * File Hooks
1632 */
1633
1634/*
1635 * There is no smack_file_permission hook
1636 *
1637 * Should access checks be done on each read or write?
1638 * UNICOS and SELinux say yes.
1639 * Trusted Solaris, Trusted Irix, and just about everyone else says no.
1640 *
1641 * I'll say no for now. Smack does not do the frequent
1642 * label changing that SELinux does.
1643 */
1644
1645/**
1646 * smack_file_alloc_security - assign a file security blob
1647 * @file: the object
1648 *
1649 * The security blob for a file is a pointer to the master
1650 * label list, so no allocation is done.
1651 *
1652 * f_security is the owner security information. It
1653 * isn't used on file access checks, it's for send_sigio.
1654 *
1655 * Returns 0
1656 */
1657static int smack_file_alloc_security(struct file *file)
1658{
1659 struct smack_known **blob = smack_file(file);
1660
1661 *blob = smk_of_current();
1662 return 0;
1663}
1664
1665/**
1666 * smack_file_ioctl - Smack check on ioctls
1667 * @file: the object
1668 * @cmd: what to do
1669 * @arg: unused
1670 *
1671 * Relies heavily on the correct use of the ioctl command conventions.
1672 *
1673 * Returns 0 if allowed, error code otherwise
1674 */
1675static int smack_file_ioctl(struct file *file, unsigned int cmd,
1676 unsigned long arg)
1677{
1678 int rc = 0;
1679 struct smk_audit_info ad;
1680 struct inode *inode = file_inode(file);
1681
1682 if (unlikely(IS_PRIVATE(inode)))
1683 return 0;
1684
1685 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1686 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1687
1688 if (_IOC_DIR(cmd) & _IOC_WRITE) {
1689 rc = smk_curacc(smk_of_inode(inode), MAY_WRITE, &ad);
1690 rc = smk_bu_file(file, MAY_WRITE, rc);
1691 }
1692
1693 if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ)) {
1694 rc = smk_curacc(smk_of_inode(inode), MAY_READ, &ad);
1695 rc = smk_bu_file(file, MAY_READ, rc);
1696 }
1697
1698 return rc;
1699}
1700
1701/**
1702 * smack_file_lock - Smack check on file locking
1703 * @file: the object
1704 * @cmd: unused
1705 *
1706 * Returns 0 if current has lock access, error code otherwise
1707 */
1708static int smack_file_lock(struct file *file, unsigned int cmd)
1709{
1710 struct smk_audit_info ad;
1711 int rc;
1712 struct inode *inode = file_inode(file);
1713
1714 if (unlikely(IS_PRIVATE(inode)))
1715 return 0;
1716
1717 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1718 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1719 rc = smk_curacc(smk_of_inode(inode), MAY_LOCK, &ad);
1720 rc = smk_bu_file(file, MAY_LOCK, rc);
1721 return rc;
1722}
1723
1724/**
1725 * smack_file_fcntl - Smack check on fcntl
1726 * @file: the object
1727 * @cmd: what action to check
1728 * @arg: unused
1729 *
1730 * Generally these operations are harmless.
1731 * File locking operations present an obvious mechanism
1732 * for passing information, so they require write access.
1733 *
1734 * Returns 0 if current has access, error code otherwise
1735 */
1736static int smack_file_fcntl(struct file *file, unsigned int cmd,
1737 unsigned long arg)
1738{
1739 struct smk_audit_info ad;
1740 int rc = 0;
1741 struct inode *inode = file_inode(file);
1742
1743 if (unlikely(IS_PRIVATE(inode)))
1744 return 0;
1745
1746 switch (cmd) {
1747 case F_GETLK:
1748 break;
1749 case F_SETLK:
1750 case F_SETLKW:
1751 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1752 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1753 rc = smk_curacc(smk_of_inode(inode), MAY_LOCK, &ad);
1754 rc = smk_bu_file(file, MAY_LOCK, rc);
1755 break;
1756 case F_SETOWN:
1757 case F_SETSIG:
1758 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1759 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1760 rc = smk_curacc(smk_of_inode(inode), MAY_WRITE, &ad);
1761 rc = smk_bu_file(file, MAY_WRITE, rc);
1762 break;
1763 default:
1764 break;
1765 }
1766
1767 return rc;
1768}
1769
1770/**
1771 * smack_mmap_file - Check permissions for a mmap operation.
1772 * @file: contains the file structure for file to map (may be NULL).
1773 * @reqprot: contains the protection requested by the application.
1774 * @prot: contains the protection that will be applied by the kernel.
1775 * @flags: contains the operational flags.
1776 *
1777 * The @file may be NULL, e.g. if mapping anonymous memory.
1778 *
1779 * Return 0 if permission is granted.
1780 */
1781static int smack_mmap_file(struct file *file,
1782 unsigned long reqprot, unsigned long prot,
1783 unsigned long flags)
1784{
1785 struct smack_known *skp;
1786 struct smack_known *mkp;
1787 struct smack_rule *srp;
1788 struct task_smack *tsp;
1789 struct smack_known *okp;
1790 struct inode_smack *isp;
1791 struct superblock_smack *sbsp;
1792 int may;
1793 int mmay;
1794 int tmay;
1795 int rc;
1796
1797 if (file == NULL)
1798 return 0;
1799
1800 if (unlikely(IS_PRIVATE(file_inode(file))))
1801 return 0;
1802
1803 isp = smack_inode(file_inode(file));
1804 if (isp->smk_mmap == NULL)
1805 return 0;
1806 sbsp = smack_superblock(file_inode(file)->i_sb);
1807 if (sbsp->smk_flags & SMK_SB_UNTRUSTED &&
1808 isp->smk_mmap != sbsp->smk_root)
1809 return -EACCES;
1810 mkp = isp->smk_mmap;
1811
1812 tsp = smack_cred(current_cred());
1813 skp = smk_of_current();
1814 rc = 0;
1815
1816 rcu_read_lock();
1817 /*
1818 * For each Smack rule associated with the subject
1819 * label verify that the SMACK64MMAP also has access
1820 * to that rule's object label.
1821 */
1822 list_for_each_entry_rcu(srp, &skp->smk_rules, list) {
1823 okp = srp->smk_object;
1824 /*
1825 * Matching labels always allows access.
1826 */
1827 if (mkp->smk_known == okp->smk_known)
1828 continue;
1829 /*
1830 * If there is a matching local rule take
1831 * that into account as well.
1832 */
1833 may = smk_access_entry(srp->smk_subject->smk_known,
1834 okp->smk_known,
1835 &tsp->smk_rules);
1836 if (may == -ENOENT)
1837 may = srp->smk_access;
1838 else
1839 may &= srp->smk_access;
1840 /*
1841 * If may is zero the SMACK64MMAP subject can't
1842 * possibly have less access.
1843 */
1844 if (may == 0)
1845 continue;
1846
1847 /*
1848 * Fetch the global list entry.
1849 * If there isn't one a SMACK64MMAP subject
1850 * can't have as much access as current.
1851 */
1852 mmay = smk_access_entry(mkp->smk_known, okp->smk_known,
1853 &mkp->smk_rules);
1854 if (mmay == -ENOENT) {
1855 rc = -EACCES;
1856 break;
1857 }
1858 /*
1859 * If there is a local entry it modifies the
1860 * potential access, too.
1861 */
1862 tmay = smk_access_entry(mkp->smk_known, okp->smk_known,
1863 &tsp->smk_rules);
1864 if (tmay != -ENOENT)
1865 mmay &= tmay;
1866
1867 /*
1868 * If there is any access available to current that is
1869 * not available to a SMACK64MMAP subject
1870 * deny access.
1871 */
1872 if ((may | mmay) != mmay) {
1873 rc = -EACCES;
1874 break;
1875 }
1876 }
1877
1878 rcu_read_unlock();
1879
1880 return rc;
1881}
1882
1883/**
1884 * smack_file_set_fowner - set the file security blob value
1885 * @file: object in question
1886 *
1887 */
1888static void smack_file_set_fowner(struct file *file)
1889{
1890 struct smack_known **blob = smack_file(file);
1891
1892 *blob = smk_of_current();
1893}
1894
1895/**
1896 * smack_file_send_sigiotask - Smack on sigio
1897 * @tsk: The target task
1898 * @fown: the object the signal come from
1899 * @signum: unused
1900 *
1901 * Allow a privileged task to get signals even if it shouldn't
1902 *
1903 * Returns 0 if a subject with the object's smack could
1904 * write to the task, an error code otherwise.
1905 */
1906static int smack_file_send_sigiotask(struct task_struct *tsk,
1907 struct fown_struct *fown, int signum)
1908{
1909 struct smack_known **blob;
1910 struct smack_known *skp;
1911 struct smack_known *tkp = smk_of_task(smack_cred(tsk->cred));
1912 const struct cred *tcred;
1913 struct file *file;
1914 int rc;
1915 struct smk_audit_info ad;
1916
1917 /*
1918 * struct fown_struct is never outside the context of a struct file
1919 */
1920 file = container_of(fown, struct file, f_owner);
1921
1922 /* we don't log here as rc can be overriden */
1923 blob = smack_file(file);
1924 skp = *blob;
1925 rc = smk_access(skp, tkp, MAY_DELIVER, NULL);
1926 rc = smk_bu_note("sigiotask", skp, tkp, MAY_DELIVER, rc);
1927
1928 rcu_read_lock();
1929 tcred = __task_cred(tsk);
1930 if (rc != 0 && smack_privileged_cred(CAP_MAC_OVERRIDE, tcred))
1931 rc = 0;
1932 rcu_read_unlock();
1933
1934 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1935 smk_ad_setfield_u_tsk(&ad, tsk);
1936 smack_log(skp->smk_known, tkp->smk_known, MAY_DELIVER, rc, &ad);
1937 return rc;
1938}
1939
1940/**
1941 * smack_file_receive - Smack file receive check
1942 * @file: the object
1943 *
1944 * Returns 0 if current has access, error code otherwise
1945 */
1946static int smack_file_receive(struct file *file)
1947{
1948 int rc;
1949 int may = 0;
1950 struct smk_audit_info ad;
1951 struct inode *inode = file_inode(file);
1952 struct socket *sock;
1953 struct task_smack *tsp;
1954 struct socket_smack *ssp;
1955
1956 if (unlikely(IS_PRIVATE(inode)))
1957 return 0;
1958
1959 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1960 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1961
1962 if (inode->i_sb->s_magic == SOCKFS_MAGIC) {
1963 sock = SOCKET_I(inode);
1964 ssp = sock->sk->sk_security;
1965 tsp = smack_cred(current_cred());
1966 /*
1967 * If the receiving process can't write to the
1968 * passed socket or if the passed socket can't
1969 * write to the receiving process don't accept
1970 * the passed socket.
1971 */
1972 rc = smk_access(tsp->smk_task, ssp->smk_out, MAY_WRITE, &ad);
1973 rc = smk_bu_file(file, may, rc);
1974 if (rc < 0)
1975 return rc;
1976 rc = smk_access(ssp->smk_in, tsp->smk_task, MAY_WRITE, &ad);
1977 rc = smk_bu_file(file, may, rc);
1978 return rc;
1979 }
1980 /*
1981 * This code relies on bitmasks.
1982 */
1983 if (file->f_mode & FMODE_READ)
1984 may = MAY_READ;
1985 if (file->f_mode & FMODE_WRITE)
1986 may |= MAY_WRITE;
1987
1988 rc = smk_curacc(smk_of_inode(inode), may, &ad);
1989 rc = smk_bu_file(file, may, rc);
1990 return rc;
1991}
1992
1993/**
1994 * smack_file_open - Smack dentry open processing
1995 * @file: the object
1996 *
1997 * Set the security blob in the file structure.
1998 * Allow the open only if the task has read access. There are
1999 * many read operations (e.g. fstat) that you can do with an
2000 * fd even if you have the file open write-only.
2001 *
2002 * Returns 0 if current has access, error code otherwise
2003 */
2004static int smack_file_open(struct file *file)
2005{
2006 struct task_smack *tsp = smack_cred(file->f_cred);
2007 struct inode *inode = file_inode(file);
2008 struct smk_audit_info ad;
2009 int rc;
2010
2011 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
2012 smk_ad_setfield_u_fs_path(&ad, file->f_path);
2013 rc = smk_tskacc(tsp, smk_of_inode(inode), MAY_READ, &ad);
2014 rc = smk_bu_credfile(file->f_cred, file, MAY_READ, rc);
2015
2016 return rc;
2017}
2018
2019/*
2020 * Task hooks
2021 */
2022
2023/**
2024 * smack_cred_alloc_blank - "allocate" blank task-level security credentials
2025 * @cred: the new credentials
2026 * @gfp: the atomicity of any memory allocations
2027 *
2028 * Prepare a blank set of credentials for modification. This must allocate all
2029 * the memory the LSM module might require such that cred_transfer() can
2030 * complete without error.
2031 */
2032static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp)
2033{
2034 init_task_smack(smack_cred(cred), NULL, NULL);
2035 return 0;
2036}
2037
2038
2039/**
2040 * smack_cred_free - "free" task-level security credentials
2041 * @cred: the credentials in question
2042 *
2043 */
2044static void smack_cred_free(struct cred *cred)
2045{
2046 struct task_smack *tsp = smack_cred(cred);
2047 struct smack_rule *rp;
2048 struct list_head *l;
2049 struct list_head *n;
2050
2051 smk_destroy_label_list(&tsp->smk_relabel);
2052
2053 list_for_each_safe(l, n, &tsp->smk_rules) {
2054 rp = list_entry(l, struct smack_rule, list);
2055 list_del(&rp->list);
2056 kmem_cache_free(smack_rule_cache, rp);
2057 }
2058}
2059
2060/**
2061 * smack_cred_prepare - prepare new set of credentials for modification
2062 * @new: the new credentials
2063 * @old: the original credentials
2064 * @gfp: the atomicity of any memory allocations
2065 *
2066 * Prepare a new set of credentials for modification.
2067 */
2068static int smack_cred_prepare(struct cred *new, const struct cred *old,
2069 gfp_t gfp)
2070{
2071 struct task_smack *old_tsp = smack_cred(old);
2072 struct task_smack *new_tsp = smack_cred(new);
2073 int rc;
2074
2075 init_task_smack(new_tsp, old_tsp->smk_task, old_tsp->smk_task);
2076
2077 rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp);
2078 if (rc != 0)
2079 return rc;
2080
2081 rc = smk_copy_relabel(&new_tsp->smk_relabel, &old_tsp->smk_relabel,
2082 gfp);
2083 return rc;
2084}
2085
2086/**
2087 * smack_cred_transfer - Transfer the old credentials to the new credentials
2088 * @new: the new credentials
2089 * @old: the original credentials
2090 *
2091 * Fill in a set of blank credentials from another set of credentials.
2092 */
2093static void smack_cred_transfer(struct cred *new, const struct cred *old)
2094{
2095 struct task_smack *old_tsp = smack_cred(old);
2096 struct task_smack *new_tsp = smack_cred(new);
2097
2098 new_tsp->smk_task = old_tsp->smk_task;
2099 new_tsp->smk_forked = old_tsp->smk_task;
2100 mutex_init(&new_tsp->smk_rules_lock);
2101 INIT_LIST_HEAD(&new_tsp->smk_rules);
2102
2103 /* cbs copy rule list */
2104}
2105
2106/**
2107 * smack_cred_getsecid - get the secid corresponding to a creds structure
2108 * @cred: the object creds
2109 * @secid: where to put the result
2110 *
2111 * Sets the secid to contain a u32 version of the smack label.
2112 */
2113static void smack_cred_getsecid(const struct cred *cred, u32 *secid)
2114{
2115 struct smack_known *skp;
2116
2117 rcu_read_lock();
2118 skp = smk_of_task(smack_cred(cred));
2119 *secid = skp->smk_secid;
2120 rcu_read_unlock();
2121}
2122
2123/**
2124 * smack_kernel_act_as - Set the subjective context in a set of credentials
2125 * @new: points to the set of credentials to be modified.
2126 * @secid: specifies the security ID to be set
2127 *
2128 * Set the security data for a kernel service.
2129 */
2130static int smack_kernel_act_as(struct cred *new, u32 secid)
2131{
2132 struct task_smack *new_tsp = smack_cred(new);
2133
2134 new_tsp->smk_task = smack_from_secid(secid);
2135 return 0;
2136}
2137
2138/**
2139 * smack_kernel_create_files_as - Set the file creation label in a set of creds
2140 * @new: points to the set of credentials to be modified
2141 * @inode: points to the inode to use as a reference
2142 *
2143 * Set the file creation context in a set of credentials to the same
2144 * as the objective context of the specified inode
2145 */
2146static int smack_kernel_create_files_as(struct cred *new,
2147 struct inode *inode)
2148{
2149 struct inode_smack *isp = smack_inode(inode);
2150 struct task_smack *tsp = smack_cred(new);
2151
2152 tsp->smk_forked = isp->smk_inode;
2153 tsp->smk_task = tsp->smk_forked;
2154 return 0;
2155}
2156
2157/**
2158 * smk_curacc_on_task - helper to log task related access
2159 * @p: the task object
2160 * @access: the access requested
2161 * @caller: name of the calling function for audit
2162 *
2163 * Return 0 if access is permitted
2164 */
2165static int smk_curacc_on_task(struct task_struct *p, int access,
2166 const char *caller)
2167{
2168 struct smk_audit_info ad;
2169 struct smack_known *skp = smk_of_task_struct_obj(p);
2170 int rc;
2171
2172 smk_ad_init(&ad, caller, LSM_AUDIT_DATA_TASK);
2173 smk_ad_setfield_u_tsk(&ad, p);
2174 rc = smk_curacc(skp, access, &ad);
2175 rc = smk_bu_task(p, access, rc);
2176 return rc;
2177}
2178
2179/**
2180 * smack_task_setpgid - Smack check on setting pgid
2181 * @p: the task object
2182 * @pgid: unused
2183 *
2184 * Return 0 if write access is permitted
2185 */
2186static int smack_task_setpgid(struct task_struct *p, pid_t pgid)
2187{
2188 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2189}
2190
2191/**
2192 * smack_task_getpgid - Smack access check for getpgid
2193 * @p: the object task
2194 *
2195 * Returns 0 if current can read the object task, error code otherwise
2196 */
2197static int smack_task_getpgid(struct task_struct *p)
2198{
2199 return smk_curacc_on_task(p, MAY_READ, __func__);
2200}
2201
2202/**
2203 * smack_task_getsid - Smack access check for getsid
2204 * @p: the object task
2205 *
2206 * Returns 0 if current can read the object task, error code otherwise
2207 */
2208static int smack_task_getsid(struct task_struct *p)
2209{
2210 return smk_curacc_on_task(p, MAY_READ, __func__);
2211}
2212
2213/**
2214 * smack_current_getsecid_subj - get the subjective secid of the current task
2215 * @secid: where to put the result
2216 *
2217 * Sets the secid to contain a u32 version of the task's subjective smack label.
2218 */
2219static void smack_current_getsecid_subj(u32 *secid)
2220{
2221 struct smack_known *skp = smk_of_current();
2222
2223 *secid = skp->smk_secid;
2224}
2225
2226/**
2227 * smack_task_getsecid_obj - get the objective secid of the task
2228 * @p: the task
2229 * @secid: where to put the result
2230 *
2231 * Sets the secid to contain a u32 version of the task's objective smack label.
2232 */
2233static void smack_task_getsecid_obj(struct task_struct *p, u32 *secid)
2234{
2235 struct smack_known *skp = smk_of_task_struct_obj(p);
2236
2237 *secid = skp->smk_secid;
2238}
2239
2240/**
2241 * smack_task_setnice - Smack check on setting nice
2242 * @p: the task object
2243 * @nice: unused
2244 *
2245 * Return 0 if write access is permitted
2246 */
2247static int smack_task_setnice(struct task_struct *p, int nice)
2248{
2249 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2250}
2251
2252/**
2253 * smack_task_setioprio - Smack check on setting ioprio
2254 * @p: the task object
2255 * @ioprio: unused
2256 *
2257 * Return 0 if write access is permitted
2258 */
2259static int smack_task_setioprio(struct task_struct *p, int ioprio)
2260{
2261 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2262}
2263
2264/**
2265 * smack_task_getioprio - Smack check on reading ioprio
2266 * @p: the task object
2267 *
2268 * Return 0 if read access is permitted
2269 */
2270static int smack_task_getioprio(struct task_struct *p)
2271{
2272 return smk_curacc_on_task(p, MAY_READ, __func__);
2273}
2274
2275/**
2276 * smack_task_setscheduler - Smack check on setting scheduler
2277 * @p: the task object
2278 *
2279 * Return 0 if read access is permitted
2280 */
2281static int smack_task_setscheduler(struct task_struct *p)
2282{
2283 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2284}
2285
2286/**
2287 * smack_task_getscheduler - Smack check on reading scheduler
2288 * @p: the task object
2289 *
2290 * Return 0 if read access is permitted
2291 */
2292static int smack_task_getscheduler(struct task_struct *p)
2293{
2294 return smk_curacc_on_task(p, MAY_READ, __func__);
2295}
2296
2297/**
2298 * smack_task_movememory - Smack check on moving memory
2299 * @p: the task object
2300 *
2301 * Return 0 if write access is permitted
2302 */
2303static int smack_task_movememory(struct task_struct *p)
2304{
2305 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2306}
2307
2308/**
2309 * smack_task_kill - Smack check on signal delivery
2310 * @p: the task object
2311 * @info: unused
2312 * @sig: unused
2313 * @cred: identifies the cred to use in lieu of current's
2314 *
2315 * Return 0 if write access is permitted
2316 *
2317 */
2318static int smack_task_kill(struct task_struct *p, struct kernel_siginfo *info,
2319 int sig, const struct cred *cred)
2320{
2321 struct smk_audit_info ad;
2322 struct smack_known *skp;
2323 struct smack_known *tkp = smk_of_task_struct_obj(p);
2324 int rc;
2325
2326 if (!sig)
2327 return 0; /* null signal; existence test */
2328
2329 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
2330 smk_ad_setfield_u_tsk(&ad, p);
2331 /*
2332 * Sending a signal requires that the sender
2333 * can write the receiver.
2334 */
2335 if (cred == NULL) {
2336 rc = smk_curacc(tkp, MAY_DELIVER, &ad);
2337 rc = smk_bu_task(p, MAY_DELIVER, rc);
2338 return rc;
2339 }
2340 /*
2341 * If the cred isn't NULL we're dealing with some USB IO
2342 * specific behavior. This is not clean. For one thing
2343 * we can't take privilege into account.
2344 */
2345 skp = smk_of_task(smack_cred(cred));
2346 rc = smk_access(skp, tkp, MAY_DELIVER, &ad);
2347 rc = smk_bu_note("USB signal", skp, tkp, MAY_DELIVER, rc);
2348 return rc;
2349}
2350
2351/**
2352 * smack_task_to_inode - copy task smack into the inode blob
2353 * @p: task to copy from
2354 * @inode: inode to copy to
2355 *
2356 * Sets the smack pointer in the inode security blob
2357 */
2358static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
2359{
2360 struct inode_smack *isp = smack_inode(inode);
2361 struct smack_known *skp = smk_of_task_struct_obj(p);
2362
2363 isp->smk_inode = skp;
2364 isp->smk_flags |= SMK_INODE_INSTANT;
2365}
2366
2367/*
2368 * Socket hooks.
2369 */
2370
2371/**
2372 * smack_sk_alloc_security - Allocate a socket blob
2373 * @sk: the socket
2374 * @family: unused
2375 * @gfp_flags: memory allocation flags
2376 *
2377 * Assign Smack pointers to current
2378 *
2379 * Returns 0 on success, -ENOMEM is there's no memory
2380 */
2381static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags)
2382{
2383 struct smack_known *skp = smk_of_current();
2384 struct socket_smack *ssp;
2385
2386 ssp = kzalloc(sizeof(struct socket_smack), gfp_flags);
2387 if (ssp == NULL)
2388 return -ENOMEM;
2389
2390 /*
2391 * Sockets created by kernel threads receive web label.
2392 */
2393 if (unlikely(current->flags & PF_KTHREAD)) {
2394 ssp->smk_in = &smack_known_web;
2395 ssp->smk_out = &smack_known_web;
2396 } else {
2397 ssp->smk_in = skp;
2398 ssp->smk_out = skp;
2399 }
2400 ssp->smk_packet = NULL;
2401
2402 sk->sk_security = ssp;
2403
2404 return 0;
2405}
2406
2407/**
2408 * smack_sk_free_security - Free a socket blob
2409 * @sk: the socket
2410 *
2411 * Clears the blob pointer
2412 */
2413static void smack_sk_free_security(struct sock *sk)
2414{
2415#ifdef SMACK_IPV6_PORT_LABELING
2416 struct smk_port_label *spp;
2417
2418 if (sk->sk_family == PF_INET6) {
2419 rcu_read_lock();
2420 list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
2421 if (spp->smk_sock != sk)
2422 continue;
2423 spp->smk_can_reuse = 1;
2424 break;
2425 }
2426 rcu_read_unlock();
2427 }
2428#endif
2429 kfree(sk->sk_security);
2430}
2431
2432/**
2433 * smack_sk_clone_security - Copy security context
2434 * @sk: the old socket
2435 * @newsk: the new socket
2436 *
2437 * Copy the security context of the old socket pointer to the cloned
2438 */
2439static void smack_sk_clone_security(const struct sock *sk, struct sock *newsk)
2440{
2441 struct socket_smack *ssp_old = sk->sk_security;
2442 struct socket_smack *ssp_new = newsk->sk_security;
2443
2444 *ssp_new = *ssp_old;
2445}
2446
2447/**
2448* smack_ipv4host_label - check host based restrictions
2449* @sip: the object end
2450*
2451* looks for host based access restrictions
2452*
2453* This version will only be appropriate for really small sets of single label
2454* hosts. The caller is responsible for ensuring that the RCU read lock is
2455* taken before calling this function.
2456*
2457* Returns the label of the far end or NULL if it's not special.
2458*/
2459static struct smack_known *smack_ipv4host_label(struct sockaddr_in *sip)
2460{
2461 struct smk_net4addr *snp;
2462 struct in_addr *siap = &sip->sin_addr;
2463
2464 if (siap->s_addr == 0)
2465 return NULL;
2466
2467 list_for_each_entry_rcu(snp, &smk_net4addr_list, list)
2468 /*
2469 * we break after finding the first match because
2470 * the list is sorted from longest to shortest mask
2471 * so we have found the most specific match
2472 */
2473 if (snp->smk_host.s_addr ==
2474 (siap->s_addr & snp->smk_mask.s_addr))
2475 return snp->smk_label;
2476
2477 return NULL;
2478}
2479
2480/*
2481 * smk_ipv6_localhost - Check for local ipv6 host address
2482 * @sip: the address
2483 *
2484 * Returns boolean true if this is the localhost address
2485 */
2486static bool smk_ipv6_localhost(struct sockaddr_in6 *sip)
2487{
2488 __be16 *be16p = (__be16 *)&sip->sin6_addr;
2489 __be32 *be32p = (__be32 *)&sip->sin6_addr;
2490
2491 if (be32p[0] == 0 && be32p[1] == 0 && be32p[2] == 0 && be16p[6] == 0 &&
2492 ntohs(be16p[7]) == 1)
2493 return true;
2494 return false;
2495}
2496
2497/**
2498* smack_ipv6host_label - check host based restrictions
2499* @sip: the object end
2500*
2501* looks for host based access restrictions
2502*
2503* This version will only be appropriate for really small sets of single label
2504* hosts. The caller is responsible for ensuring that the RCU read lock is
2505* taken before calling this function.
2506*
2507* Returns the label of the far end or NULL if it's not special.
2508*/
2509static struct smack_known *smack_ipv6host_label(struct sockaddr_in6 *sip)
2510{
2511 struct smk_net6addr *snp;
2512 struct in6_addr *sap = &sip->sin6_addr;
2513 int i;
2514 int found = 0;
2515
2516 /*
2517 * It's local. Don't look for a host label.
2518 */
2519 if (smk_ipv6_localhost(sip))
2520 return NULL;
2521
2522 list_for_each_entry_rcu(snp, &smk_net6addr_list, list) {
2523 /*
2524 * If the label is NULL the entry has
2525 * been renounced. Ignore it.
2526 */
2527 if (snp->smk_label == NULL)
2528 continue;
2529 /*
2530 * we break after finding the first match because
2531 * the list is sorted from longest to shortest mask
2532 * so we have found the most specific match
2533 */
2534 for (found = 1, i = 0; i < 8; i++) {
2535 if ((sap->s6_addr16[i] & snp->smk_mask.s6_addr16[i]) !=
2536 snp->smk_host.s6_addr16[i]) {
2537 found = 0;
2538 break;
2539 }
2540 }
2541 if (found)
2542 return snp->smk_label;
2543 }
2544
2545 return NULL;
2546}
2547
2548/**
2549 * smack_netlbl_add - Set the secattr on a socket
2550 * @sk: the socket
2551 *
2552 * Attach the outbound smack value (smk_out) to the socket.
2553 *
2554 * Returns 0 on success or an error code
2555 */
2556static int smack_netlbl_add(struct sock *sk)
2557{
2558 struct socket_smack *ssp = sk->sk_security;
2559 struct smack_known *skp = ssp->smk_out;
2560 int rc;
2561
2562 local_bh_disable();
2563 bh_lock_sock_nested(sk);
2564
2565 rc = netlbl_sock_setattr(sk, sk->sk_family, &skp->smk_netlabel);
2566 switch (rc) {
2567 case 0:
2568 ssp->smk_state = SMK_NETLBL_LABELED;
2569 break;
2570 case -EDESTADDRREQ:
2571 ssp->smk_state = SMK_NETLBL_REQSKB;
2572 rc = 0;
2573 break;
2574 }
2575
2576 bh_unlock_sock(sk);
2577 local_bh_enable();
2578
2579 return rc;
2580}
2581
2582/**
2583 * smack_netlbl_delete - Remove the secattr from a socket
2584 * @sk: the socket
2585 *
2586 * Remove the outbound smack value from a socket
2587 */
2588static void smack_netlbl_delete(struct sock *sk)
2589{
2590 struct socket_smack *ssp = sk->sk_security;
2591
2592 /*
2593 * Take the label off the socket if one is set.
2594 */
2595 if (ssp->smk_state != SMK_NETLBL_LABELED)
2596 return;
2597
2598 local_bh_disable();
2599 bh_lock_sock_nested(sk);
2600 netlbl_sock_delattr(sk);
2601 bh_unlock_sock(sk);
2602 local_bh_enable();
2603 ssp->smk_state = SMK_NETLBL_UNLABELED;
2604}
2605
2606/**
2607 * smk_ipv4_check - Perform IPv4 host access checks
2608 * @sk: the socket
2609 * @sap: the destination address
2610 *
2611 * Set the correct secattr for the given socket based on the destination
2612 * address and perform any outbound access checks needed.
2613 *
2614 * Returns 0 on success or an error code.
2615 *
2616 */
2617static int smk_ipv4_check(struct sock *sk, struct sockaddr_in *sap)
2618{
2619 struct smack_known *skp;
2620 int rc = 0;
2621 struct smack_known *hkp;
2622 struct socket_smack *ssp = sk->sk_security;
2623 struct smk_audit_info ad;
2624
2625 rcu_read_lock();
2626 hkp = smack_ipv4host_label(sap);
2627 if (hkp != NULL) {
2628#ifdef CONFIG_AUDIT
2629 struct lsm_network_audit net;
2630
2631 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
2632 ad.a.u.net->family = sap->sin_family;
2633 ad.a.u.net->dport = sap->sin_port;
2634 ad.a.u.net->v4info.daddr = sap->sin_addr.s_addr;
2635#endif
2636 skp = ssp->smk_out;
2637 rc = smk_access(skp, hkp, MAY_WRITE, &ad);
2638 rc = smk_bu_note("IPv4 host check", skp, hkp, MAY_WRITE, rc);
2639 /*
2640 * Clear the socket netlabel if it's set.
2641 */
2642 if (!rc)
2643 smack_netlbl_delete(sk);
2644 }
2645 rcu_read_unlock();
2646
2647 return rc;
2648}
2649
2650/**
2651 * smk_ipv6_check - check Smack access
2652 * @subject: subject Smack label
2653 * @object: object Smack label
2654 * @address: address
2655 * @act: the action being taken
2656 *
2657 * Check an IPv6 access
2658 */
2659static int smk_ipv6_check(struct smack_known *subject,
2660 struct smack_known *object,
2661 struct sockaddr_in6 *address, int act)
2662{
2663#ifdef CONFIG_AUDIT
2664 struct lsm_network_audit net;
2665#endif
2666 struct smk_audit_info ad;
2667 int rc;
2668
2669#ifdef CONFIG_AUDIT
2670 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
2671 ad.a.u.net->family = PF_INET6;
2672 ad.a.u.net->dport = address->sin6_port;
2673 if (act == SMK_RECEIVING)
2674 ad.a.u.net->v6info.saddr = address->sin6_addr;
2675 else
2676 ad.a.u.net->v6info.daddr = address->sin6_addr;
2677#endif
2678 rc = smk_access(subject, object, MAY_WRITE, &ad);
2679 rc = smk_bu_note("IPv6 check", subject, object, MAY_WRITE, rc);
2680 return rc;
2681}
2682
2683#ifdef SMACK_IPV6_PORT_LABELING
2684/**
2685 * smk_ipv6_port_label - Smack port access table management
2686 * @sock: socket
2687 * @address: address
2688 *
2689 * Create or update the port list entry
2690 */
2691static void smk_ipv6_port_label(struct socket *sock, struct sockaddr *address)
2692{
2693 struct sock *sk = sock->sk;
2694 struct sockaddr_in6 *addr6;
2695 struct socket_smack *ssp = sock->sk->sk_security;
2696 struct smk_port_label *spp;
2697 unsigned short port = 0;
2698
2699 if (address == NULL) {
2700 /*
2701 * This operation is changing the Smack information
2702 * on the bound socket. Take the changes to the port
2703 * as well.
2704 */
2705 rcu_read_lock();
2706 list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
2707 if (sk != spp->smk_sock)
2708 continue;
2709 spp->smk_in = ssp->smk_in;
2710 spp->smk_out = ssp->smk_out;
2711 rcu_read_unlock();
2712 return;
2713 }
2714 /*
2715 * A NULL address is only used for updating existing
2716 * bound entries. If there isn't one, it's OK.
2717 */
2718 rcu_read_unlock();
2719 return;
2720 }
2721
2722 addr6 = (struct sockaddr_in6 *)address;
2723 port = ntohs(addr6->sin6_port);
2724 /*
2725 * This is a special case that is safely ignored.
2726 */
2727 if (port == 0)
2728 return;
2729
2730 /*
2731 * Look for an existing port list entry.
2732 * This is an indication that a port is getting reused.
2733 */
2734 rcu_read_lock();
2735 list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
2736 if (spp->smk_port != port || spp->smk_sock_type != sock->type)
2737 continue;
2738 if (spp->smk_can_reuse != 1) {
2739 rcu_read_unlock();
2740 return;
2741 }
2742 spp->smk_port = port;
2743 spp->smk_sock = sk;
2744 spp->smk_in = ssp->smk_in;
2745 spp->smk_out = ssp->smk_out;
2746 spp->smk_can_reuse = 0;
2747 rcu_read_unlock();
2748 return;
2749 }
2750 rcu_read_unlock();
2751 /*
2752 * A new port entry is required.
2753 */
2754 spp = kzalloc(sizeof(*spp), GFP_KERNEL);
2755 if (spp == NULL)
2756 return;
2757
2758 spp->smk_port = port;
2759 spp->smk_sock = sk;
2760 spp->smk_in = ssp->smk_in;
2761 spp->smk_out = ssp->smk_out;
2762 spp->smk_sock_type = sock->type;
2763 spp->smk_can_reuse = 0;
2764
2765 mutex_lock(&smack_ipv6_lock);
2766 list_add_rcu(&spp->list, &smk_ipv6_port_list);
2767 mutex_unlock(&smack_ipv6_lock);
2768 return;
2769}
2770
2771/**
2772 * smk_ipv6_port_check - check Smack port access
2773 * @sk: socket
2774 * @address: address
2775 * @act: the action being taken
2776 *
2777 * Create or update the port list entry
2778 */
2779static int smk_ipv6_port_check(struct sock *sk, struct sockaddr_in6 *address,
2780 int act)
2781{
2782 struct smk_port_label *spp;
2783 struct socket_smack *ssp = sk->sk_security;
2784 struct smack_known *skp = NULL;
2785 unsigned short port;
2786 struct smack_known *object;
2787
2788 if (act == SMK_RECEIVING) {
2789 skp = smack_ipv6host_label(address);
2790 object = ssp->smk_in;
2791 } else {
2792 skp = ssp->smk_out;
2793 object = smack_ipv6host_label(address);
2794 }
2795
2796 /*
2797 * The other end is a single label host.
2798 */
2799 if (skp != NULL && object != NULL)
2800 return smk_ipv6_check(skp, object, address, act);
2801 if (skp == NULL)
2802 skp = smack_net_ambient;
2803 if (object == NULL)
2804 object = smack_net_ambient;
2805
2806 /*
2807 * It's remote, so port lookup does no good.
2808 */
2809 if (!smk_ipv6_localhost(address))
2810 return smk_ipv6_check(skp, object, address, act);
2811
2812 /*
2813 * It's local so the send check has to have passed.
2814 */
2815 if (act == SMK_RECEIVING)
2816 return 0;
2817
2818 port = ntohs(address->sin6_port);
2819 rcu_read_lock();
2820 list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
2821 if (spp->smk_port != port || spp->smk_sock_type != sk->sk_type)
2822 continue;
2823 object = spp->smk_in;
2824 if (act == SMK_CONNECTING)
2825 ssp->smk_packet = spp->smk_out;
2826 break;
2827 }
2828 rcu_read_unlock();
2829
2830 return smk_ipv6_check(skp, object, address, act);
2831}
2832#endif
2833
2834/**
2835 * smack_inode_setsecurity - set smack xattrs
2836 * @inode: the object
2837 * @name: attribute name
2838 * @value: attribute value
2839 * @size: size of the attribute
2840 * @flags: unused
2841 *
2842 * Sets the named attribute in the appropriate blob
2843 *
2844 * Returns 0 on success, or an error code
2845 */
2846static int smack_inode_setsecurity(struct inode *inode, const char *name,
2847 const void *value, size_t size, int flags)
2848{
2849 struct smack_known *skp;
2850 struct inode_smack *nsp = smack_inode(inode);
2851 struct socket_smack *ssp;
2852 struct socket *sock;
2853 int rc = 0;
2854
2855 if (value == NULL || size > SMK_LONGLABEL || size == 0)
2856 return -EINVAL;
2857
2858 skp = smk_import_entry(value, size);
2859 if (IS_ERR(skp))
2860 return PTR_ERR(skp);
2861
2862 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
2863 nsp->smk_inode = skp;
2864 nsp->smk_flags |= SMK_INODE_INSTANT;
2865 return 0;
2866 }
2867 /*
2868 * The rest of the Smack xattrs are only on sockets.
2869 */
2870 if (inode->i_sb->s_magic != SOCKFS_MAGIC)
2871 return -EOPNOTSUPP;
2872
2873 sock = SOCKET_I(inode);
2874 if (sock == NULL || sock->sk == NULL)
2875 return -EOPNOTSUPP;
2876
2877 ssp = sock->sk->sk_security;
2878
2879 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
2880 ssp->smk_in = skp;
2881 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) {
2882 ssp->smk_out = skp;
2883 if (sock->sk->sk_family == PF_INET) {
2884 rc = smack_netlbl_add(sock->sk);
2885 if (rc != 0)
2886 printk(KERN_WARNING
2887 "Smack: \"%s\" netlbl error %d.\n",
2888 __func__, -rc);
2889 }
2890 } else
2891 return -EOPNOTSUPP;
2892
2893#ifdef SMACK_IPV6_PORT_LABELING
2894 if (sock->sk->sk_family == PF_INET6)
2895 smk_ipv6_port_label(sock, NULL);
2896#endif
2897
2898 return 0;
2899}
2900
2901/**
2902 * smack_socket_post_create - finish socket setup
2903 * @sock: the socket
2904 * @family: protocol family
2905 * @type: unused
2906 * @protocol: unused
2907 * @kern: unused
2908 *
2909 * Sets the netlabel information on the socket
2910 *
2911 * Returns 0 on success, and error code otherwise
2912 */
2913static int smack_socket_post_create(struct socket *sock, int family,
2914 int type, int protocol, int kern)
2915{
2916 struct socket_smack *ssp;
2917
2918 if (sock->sk == NULL)
2919 return 0;
2920
2921 /*
2922 * Sockets created by kernel threads receive web label.
2923 */
2924 if (unlikely(current->flags & PF_KTHREAD)) {
2925 ssp = sock->sk->sk_security;
2926 ssp->smk_in = &smack_known_web;
2927 ssp->smk_out = &smack_known_web;
2928 }
2929
2930 if (family != PF_INET)
2931 return 0;
2932 /*
2933 * Set the outbound netlbl.
2934 */
2935 return smack_netlbl_add(sock->sk);
2936}
2937
2938/**
2939 * smack_socket_socketpair - create socket pair
2940 * @socka: one socket
2941 * @sockb: another socket
2942 *
2943 * Cross reference the peer labels for SO_PEERSEC
2944 *
2945 * Returns 0
2946 */
2947static int smack_socket_socketpair(struct socket *socka,
2948 struct socket *sockb)
2949{
2950 struct socket_smack *asp = socka->sk->sk_security;
2951 struct socket_smack *bsp = sockb->sk->sk_security;
2952
2953 asp->smk_packet = bsp->smk_out;
2954 bsp->smk_packet = asp->smk_out;
2955
2956 return 0;
2957}
2958
2959#ifdef SMACK_IPV6_PORT_LABELING
2960/**
2961 * smack_socket_bind - record port binding information.
2962 * @sock: the socket
2963 * @address: the port address
2964 * @addrlen: size of the address
2965 *
2966 * Records the label bound to a port.
2967 *
2968 * Returns 0 on success, and error code otherwise
2969 */
2970static int smack_socket_bind(struct socket *sock, struct sockaddr *address,
2971 int addrlen)
2972{
2973 if (sock->sk != NULL && sock->sk->sk_family == PF_INET6) {
2974 if (addrlen < SIN6_LEN_RFC2133 ||
2975 address->sa_family != AF_INET6)
2976 return -EINVAL;
2977 smk_ipv6_port_label(sock, address);
2978 }
2979 return 0;
2980}
2981#endif /* SMACK_IPV6_PORT_LABELING */
2982
2983/**
2984 * smack_socket_connect - connect access check
2985 * @sock: the socket
2986 * @sap: the other end
2987 * @addrlen: size of sap
2988 *
2989 * Verifies that a connection may be possible
2990 *
2991 * Returns 0 on success, and error code otherwise
2992 */
2993static int smack_socket_connect(struct socket *sock, struct sockaddr *sap,
2994 int addrlen)
2995{
2996 int rc = 0;
2997
2998 if (sock->sk == NULL)
2999 return 0;
3000 if (sock->sk->sk_family != PF_INET &&
3001 (!IS_ENABLED(CONFIG_IPV6) || sock->sk->sk_family != PF_INET6))
3002 return 0;
3003 if (addrlen < offsetofend(struct sockaddr, sa_family))
3004 return 0;
3005 if (IS_ENABLED(CONFIG_IPV6) && sap->sa_family == AF_INET6) {
3006 struct sockaddr_in6 *sip = (struct sockaddr_in6 *)sap;
3007 struct smack_known *rsp = NULL;
3008
3009 if (addrlen < SIN6_LEN_RFC2133)
3010 return 0;
3011 if (__is_defined(SMACK_IPV6_SECMARK_LABELING))
3012 rsp = smack_ipv6host_label(sip);
3013 if (rsp != NULL) {
3014 struct socket_smack *ssp = sock->sk->sk_security;
3015
3016 rc = smk_ipv6_check(ssp->smk_out, rsp, sip,
3017 SMK_CONNECTING);
3018 }
3019#ifdef SMACK_IPV6_PORT_LABELING
3020 rc = smk_ipv6_port_check(sock->sk, sip, SMK_CONNECTING);
3021#endif
3022
3023 return rc;
3024 }
3025 if (sap->sa_family != AF_INET || addrlen < sizeof(struct sockaddr_in))
3026 return 0;
3027 rc = smk_ipv4_check(sock->sk, (struct sockaddr_in *)sap);
3028 return rc;
3029}
3030
3031/**
3032 * smack_flags_to_may - convert S_ to MAY_ values
3033 * @flags: the S_ value
3034 *
3035 * Returns the equivalent MAY_ value
3036 */
3037static int smack_flags_to_may(int flags)
3038{
3039 int may = 0;
3040
3041 if (flags & S_IRUGO)
3042 may |= MAY_READ;
3043 if (flags & S_IWUGO)
3044 may |= MAY_WRITE;
3045 if (flags & S_IXUGO)
3046 may |= MAY_EXEC;
3047
3048 return may;
3049}
3050
3051/**
3052 * smack_msg_msg_alloc_security - Set the security blob for msg_msg
3053 * @msg: the object
3054 *
3055 * Returns 0
3056 */
3057static int smack_msg_msg_alloc_security(struct msg_msg *msg)
3058{
3059 struct smack_known **blob = smack_msg_msg(msg);
3060
3061 *blob = smk_of_current();
3062 return 0;
3063}
3064
3065/**
3066 * smack_of_ipc - the smack pointer for the ipc
3067 * @isp: the object
3068 *
3069 * Returns a pointer to the smack value
3070 */
3071static struct smack_known *smack_of_ipc(struct kern_ipc_perm *isp)
3072{
3073 struct smack_known **blob = smack_ipc(isp);
3074
3075 return *blob;
3076}
3077
3078/**
3079 * smack_ipc_alloc_security - Set the security blob for ipc
3080 * @isp: the object
3081 *
3082 * Returns 0
3083 */
3084static int smack_ipc_alloc_security(struct kern_ipc_perm *isp)
3085{
3086 struct smack_known **blob = smack_ipc(isp);
3087
3088 *blob = smk_of_current();
3089 return 0;
3090}
3091
3092/**
3093 * smk_curacc_shm : check if current has access on shm
3094 * @isp : the object
3095 * @access : access requested
3096 *
3097 * Returns 0 if current has the requested access, error code otherwise
3098 */
3099static int smk_curacc_shm(struct kern_ipc_perm *isp, int access)
3100{
3101 struct smack_known *ssp = smack_of_ipc(isp);
3102 struct smk_audit_info ad;
3103 int rc;
3104
3105#ifdef CONFIG_AUDIT
3106 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
3107 ad.a.u.ipc_id = isp->id;
3108#endif
3109 rc = smk_curacc(ssp, access, &ad);
3110 rc = smk_bu_current("shm", ssp, access, rc);
3111 return rc;
3112}
3113
3114/**
3115 * smack_shm_associate - Smack access check for shm
3116 * @isp: the object
3117 * @shmflg: access requested
3118 *
3119 * Returns 0 if current has the requested access, error code otherwise
3120 */
3121static int smack_shm_associate(struct kern_ipc_perm *isp, int shmflg)
3122{
3123 int may;
3124
3125 may = smack_flags_to_may(shmflg);
3126 return smk_curacc_shm(isp, may);
3127}
3128
3129/**
3130 * smack_shm_shmctl - Smack access check for shm
3131 * @isp: the object
3132 * @cmd: what it wants to do
3133 *
3134 * Returns 0 if current has the requested access, error code otherwise
3135 */
3136static int smack_shm_shmctl(struct kern_ipc_perm *isp, int cmd)
3137{
3138 int may;
3139
3140 switch (cmd) {
3141 case IPC_STAT:
3142 case SHM_STAT:
3143 case SHM_STAT_ANY:
3144 may = MAY_READ;
3145 break;
3146 case IPC_SET:
3147 case SHM_LOCK:
3148 case SHM_UNLOCK:
3149 case IPC_RMID:
3150 may = MAY_READWRITE;
3151 break;
3152 case IPC_INFO:
3153 case SHM_INFO:
3154 /*
3155 * System level information.
3156 */
3157 return 0;
3158 default:
3159 return -EINVAL;
3160 }
3161 return smk_curacc_shm(isp, may);
3162}
3163
3164/**
3165 * smack_shm_shmat - Smack access for shmat
3166 * @isp: the object
3167 * @shmaddr: unused
3168 * @shmflg: access requested
3169 *
3170 * Returns 0 if current has the requested access, error code otherwise
3171 */
3172static int smack_shm_shmat(struct kern_ipc_perm *isp, char __user *shmaddr,
3173 int shmflg)
3174{
3175 int may;
3176
3177 may = smack_flags_to_may(shmflg);
3178 return smk_curacc_shm(isp, may);
3179}
3180
3181/**
3182 * smk_curacc_sem : check if current has access on sem
3183 * @isp : the object
3184 * @access : access requested
3185 *
3186 * Returns 0 if current has the requested access, error code otherwise
3187 */
3188static int smk_curacc_sem(struct kern_ipc_perm *isp, int access)
3189{
3190 struct smack_known *ssp = smack_of_ipc(isp);
3191 struct smk_audit_info ad;
3192 int rc;
3193
3194#ifdef CONFIG_AUDIT
3195 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
3196 ad.a.u.ipc_id = isp->id;
3197#endif
3198 rc = smk_curacc(ssp, access, &ad);
3199 rc = smk_bu_current("sem", ssp, access, rc);
3200 return rc;
3201}
3202
3203/**
3204 * smack_sem_associate - Smack access check for sem
3205 * @isp: the object
3206 * @semflg: access requested
3207 *
3208 * Returns 0 if current has the requested access, error code otherwise
3209 */
3210static int smack_sem_associate(struct kern_ipc_perm *isp, int semflg)
3211{
3212 int may;
3213
3214 may = smack_flags_to_may(semflg);
3215 return smk_curacc_sem(isp, may);
3216}
3217
3218/**
3219 * smack_sem_semctl - Smack access check for sem
3220 * @isp: the object
3221 * @cmd: what it wants to do
3222 *
3223 * Returns 0 if current has the requested access, error code otherwise
3224 */
3225static int smack_sem_semctl(struct kern_ipc_perm *isp, int cmd)
3226{
3227 int may;
3228
3229 switch (cmd) {
3230 case GETPID:
3231 case GETNCNT:
3232 case GETZCNT:
3233 case GETVAL:
3234 case GETALL:
3235 case IPC_STAT:
3236 case SEM_STAT:
3237 case SEM_STAT_ANY:
3238 may = MAY_READ;
3239 break;
3240 case SETVAL:
3241 case SETALL:
3242 case IPC_RMID:
3243 case IPC_SET:
3244 may = MAY_READWRITE;
3245 break;
3246 case IPC_INFO:
3247 case SEM_INFO:
3248 /*
3249 * System level information
3250 */
3251 return 0;
3252 default:
3253 return -EINVAL;
3254 }
3255
3256 return smk_curacc_sem(isp, may);
3257}
3258
3259/**
3260 * smack_sem_semop - Smack checks of semaphore operations
3261 * @isp: the object
3262 * @sops: unused
3263 * @nsops: unused
3264 * @alter: unused
3265 *
3266 * Treated as read and write in all cases.
3267 *
3268 * Returns 0 if access is allowed, error code otherwise
3269 */
3270static int smack_sem_semop(struct kern_ipc_perm *isp, struct sembuf *sops,
3271 unsigned nsops, int alter)
3272{
3273 return smk_curacc_sem(isp, MAY_READWRITE);
3274}
3275
3276/**
3277 * smk_curacc_msq : helper to check if current has access on msq
3278 * @isp : the msq
3279 * @access : access requested
3280 *
3281 * return 0 if current has access, error otherwise
3282 */
3283static int smk_curacc_msq(struct kern_ipc_perm *isp, int access)
3284{
3285 struct smack_known *msp = smack_of_ipc(isp);
3286 struct smk_audit_info ad;
3287 int rc;
3288
3289#ifdef CONFIG_AUDIT
3290 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
3291 ad.a.u.ipc_id = isp->id;
3292#endif
3293 rc = smk_curacc(msp, access, &ad);
3294 rc = smk_bu_current("msq", msp, access, rc);
3295 return rc;
3296}
3297
3298/**
3299 * smack_msg_queue_associate - Smack access check for msg_queue
3300 * @isp: the object
3301 * @msqflg: access requested
3302 *
3303 * Returns 0 if current has the requested access, error code otherwise
3304 */
3305static int smack_msg_queue_associate(struct kern_ipc_perm *isp, int msqflg)
3306{
3307 int may;
3308
3309 may = smack_flags_to_may(msqflg);
3310 return smk_curacc_msq(isp, may);
3311}
3312
3313/**
3314 * smack_msg_queue_msgctl - Smack access check for msg_queue
3315 * @isp: the object
3316 * @cmd: what it wants to do
3317 *
3318 * Returns 0 if current has the requested access, error code otherwise
3319 */
3320static int smack_msg_queue_msgctl(struct kern_ipc_perm *isp, int cmd)
3321{
3322 int may;
3323
3324 switch (cmd) {
3325 case IPC_STAT:
3326 case MSG_STAT:
3327 case MSG_STAT_ANY:
3328 may = MAY_READ;
3329 break;
3330 case IPC_SET:
3331 case IPC_RMID:
3332 may = MAY_READWRITE;
3333 break;
3334 case IPC_INFO:
3335 case MSG_INFO:
3336 /*
3337 * System level information
3338 */
3339 return 0;
3340 default:
3341 return -EINVAL;
3342 }
3343
3344 return smk_curacc_msq(isp, may);
3345}
3346
3347/**
3348 * smack_msg_queue_msgsnd - Smack access check for msg_queue
3349 * @isp: the object
3350 * @msg: unused
3351 * @msqflg: access requested
3352 *
3353 * Returns 0 if current has the requested access, error code otherwise
3354 */
3355static int smack_msg_queue_msgsnd(struct kern_ipc_perm *isp, struct msg_msg *msg,
3356 int msqflg)
3357{
3358 int may;
3359
3360 may = smack_flags_to_may(msqflg);
3361 return smk_curacc_msq(isp, may);
3362}
3363
3364/**
3365 * smack_msg_queue_msgrcv - Smack access check for msg_queue
3366 * @isp: the object
3367 * @msg: unused
3368 * @target: unused
3369 * @type: unused
3370 * @mode: unused
3371 *
3372 * Returns 0 if current has read and write access, error code otherwise
3373 */
3374static int smack_msg_queue_msgrcv(struct kern_ipc_perm *isp,
3375 struct msg_msg *msg,
3376 struct task_struct *target, long type,
3377 int mode)
3378{
3379 return smk_curacc_msq(isp, MAY_READWRITE);
3380}
3381
3382/**
3383 * smack_ipc_permission - Smack access for ipc_permission()
3384 * @ipp: the object permissions
3385 * @flag: access requested
3386 *
3387 * Returns 0 if current has read and write access, error code otherwise
3388 */
3389static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag)
3390{
3391 struct smack_known **blob = smack_ipc(ipp);
3392 struct smack_known *iskp = *blob;
3393 int may = smack_flags_to_may(flag);
3394 struct smk_audit_info ad;
3395 int rc;
3396
3397#ifdef CONFIG_AUDIT
3398 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
3399 ad.a.u.ipc_id = ipp->id;
3400#endif
3401 rc = smk_curacc(iskp, may, &ad);
3402 rc = smk_bu_current("svipc", iskp, may, rc);
3403 return rc;
3404}
3405
3406/**
3407 * smack_ipc_getsecid - Extract smack security id
3408 * @ipp: the object permissions
3409 * @secid: where result will be saved
3410 */
3411static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid)
3412{
3413 struct smack_known **blob = smack_ipc(ipp);
3414 struct smack_known *iskp = *blob;
3415
3416 *secid = iskp->smk_secid;
3417}
3418
3419/**
3420 * smack_d_instantiate - Make sure the blob is correct on an inode
3421 * @opt_dentry: dentry where inode will be attached
3422 * @inode: the object
3423 *
3424 * Set the inode's security blob if it hasn't been done already.
3425 */
3426static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
3427{
3428 struct super_block *sbp;
3429 struct superblock_smack *sbsp;
3430 struct inode_smack *isp;
3431 struct smack_known *skp;
3432 struct smack_known *ckp = smk_of_current();
3433 struct smack_known *final;
3434 char trattr[TRANS_TRUE_SIZE];
3435 int transflag = 0;
3436 int rc;
3437 struct dentry *dp;
3438
3439 if (inode == NULL)
3440 return;
3441
3442 isp = smack_inode(inode);
3443
3444 /*
3445 * If the inode is already instantiated
3446 * take the quick way out
3447 */
3448 if (isp->smk_flags & SMK_INODE_INSTANT)
3449 return;
3450
3451 sbp = inode->i_sb;
3452 sbsp = smack_superblock(sbp);
3453 /*
3454 * We're going to use the superblock default label
3455 * if there's no label on the file.
3456 */
3457 final = sbsp->smk_default;
3458
3459 /*
3460 * If this is the root inode the superblock
3461 * may be in the process of initialization.
3462 * If that is the case use the root value out
3463 * of the superblock.
3464 */
3465 if (opt_dentry->d_parent == opt_dentry) {
3466 switch (sbp->s_magic) {
3467 case CGROUP_SUPER_MAGIC:
3468 case CGROUP2_SUPER_MAGIC:
3469 /*
3470 * The cgroup filesystem is never mounted,
3471 * so there's no opportunity to set the mount
3472 * options.
3473 */
3474 sbsp->smk_root = &smack_known_star;
3475 sbsp->smk_default = &smack_known_star;
3476 isp->smk_inode = sbsp->smk_root;
3477 break;
3478 case TMPFS_MAGIC:
3479 /*
3480 * What about shmem/tmpfs anonymous files with dentry
3481 * obtained from d_alloc_pseudo()?
3482 */
3483 isp->smk_inode = smk_of_current();
3484 break;
3485 case PIPEFS_MAGIC:
3486 isp->smk_inode = smk_of_current();
3487 break;
3488 case SOCKFS_MAGIC:
3489 /*
3490 * Socket access is controlled by the socket
3491 * structures associated with the task involved.
3492 */
3493 isp->smk_inode = &smack_known_star;
3494 break;
3495 default:
3496 isp->smk_inode = sbsp->smk_root;
3497 break;
3498 }
3499 isp->smk_flags |= SMK_INODE_INSTANT;
3500 return;
3501 }
3502
3503 /*
3504 * This is pretty hackish.
3505 * Casey says that we shouldn't have to do
3506 * file system specific code, but it does help
3507 * with keeping it simple.
3508 */
3509 switch (sbp->s_magic) {
3510 case SMACK_MAGIC:
3511 case CGROUP_SUPER_MAGIC:
3512 case CGROUP2_SUPER_MAGIC:
3513 /*
3514 * Casey says that it's a little embarrassing
3515 * that the smack file system doesn't do
3516 * extended attributes.
3517 *
3518 * Cgroupfs is special
3519 */
3520 final = &smack_known_star;
3521 break;
3522 case DEVPTS_SUPER_MAGIC:
3523 /*
3524 * devpts seems content with the label of the task.
3525 * Programs that change smack have to treat the
3526 * pty with respect.
3527 */
3528 final = ckp;
3529 break;
3530 case PROC_SUPER_MAGIC:
3531 /*
3532 * Casey says procfs appears not to care.
3533 * The superblock default suffices.
3534 */
3535 break;
3536 case TMPFS_MAGIC:
3537 /*
3538 * Device labels should come from the filesystem,
3539 * but watch out, because they're volitile,
3540 * getting recreated on every reboot.
3541 */
3542 final = &smack_known_star;
3543 /*
3544 * If a smack value has been set we want to use it,
3545 * but since tmpfs isn't giving us the opportunity
3546 * to set mount options simulate setting the
3547 * superblock default.
3548 */
3549 fallthrough;
3550 default:
3551 /*
3552 * This isn't an understood special case.
3553 * Get the value from the xattr.
3554 */
3555
3556 /*
3557 * UNIX domain sockets use lower level socket data.
3558 */
3559 if (S_ISSOCK(inode->i_mode)) {
3560 final = &smack_known_star;
3561 break;
3562 }
3563 /*
3564 * No xattr support means, alas, no SMACK label.
3565 * Use the aforeapplied default.
3566 * It would be curious if the label of the task
3567 * does not match that assigned.
3568 */
3569 if (!(inode->i_opflags & IOP_XATTR))
3570 break;
3571 /*
3572 * Get the dentry for xattr.
3573 */
3574 dp = dget(opt_dentry);
3575 skp = smk_fetch(XATTR_NAME_SMACK, inode, dp);
3576 if (!IS_ERR_OR_NULL(skp))
3577 final = skp;
3578
3579 /*
3580 * Transmuting directory
3581 */
3582 if (S_ISDIR(inode->i_mode)) {
3583 /*
3584 * If this is a new directory and the label was
3585 * transmuted when the inode was initialized
3586 * set the transmute attribute on the directory
3587 * and mark the inode.
3588 *
3589 * If there is a transmute attribute on the
3590 * directory mark the inode.
3591 */
3592 rc = __vfs_getxattr(dp, inode,
3593 XATTR_NAME_SMACKTRANSMUTE, trattr,
3594 TRANS_TRUE_SIZE);
3595 if (rc >= 0 && strncmp(trattr, TRANS_TRUE,
3596 TRANS_TRUE_SIZE) != 0)
3597 rc = -EINVAL;
3598 if (rc >= 0)
3599 transflag = SMK_INODE_TRANSMUTE;
3600 }
3601 /*
3602 * Don't let the exec or mmap label be "*" or "@".
3603 */
3604 skp = smk_fetch(XATTR_NAME_SMACKEXEC, inode, dp);
3605 if (IS_ERR(skp) || skp == &smack_known_star ||
3606 skp == &smack_known_web)
3607 skp = NULL;
3608 isp->smk_task = skp;
3609
3610 skp = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp);
3611 if (IS_ERR(skp) || skp == &smack_known_star ||
3612 skp == &smack_known_web)
3613 skp = NULL;
3614 isp->smk_mmap = skp;
3615
3616 dput(dp);
3617 break;
3618 }
3619
3620 if (final == NULL)
3621 isp->smk_inode = ckp;
3622 else
3623 isp->smk_inode = final;
3624
3625 isp->smk_flags |= (SMK_INODE_INSTANT | transflag);
3626
3627 return;
3628}
3629
3630/**
3631 * smack_getselfattr - Smack current process attribute
3632 * @attr: which attribute to fetch
3633 * @ctx: buffer to receive the result
3634 * @size: available size in, actual size out
3635 * @flags: unused
3636 *
3637 * Fill the passed user space @ctx with the details of the requested
3638 * attribute.
3639 *
3640 * Returns the number of attributes on success, an error code otherwise.
3641 * There will only ever be one attribute.
3642 */
3643static int smack_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
3644 size_t *size, u32 flags)
3645{
3646 int rc;
3647 struct smack_known *skp;
3648
3649 if (attr != LSM_ATTR_CURRENT)
3650 return -EOPNOTSUPP;
3651
3652 skp = smk_of_current();
3653 rc = lsm_fill_user_ctx(ctx, size,
3654 skp->smk_known, strlen(skp->smk_known) + 1,
3655 LSM_ID_SMACK, 0);
3656 return (!rc ? 1 : rc);
3657}
3658
3659/**
3660 * smack_getprocattr - Smack process attribute access
3661 * @p: the object task
3662 * @name: the name of the attribute in /proc/.../attr
3663 * @value: where to put the result
3664 *
3665 * Places a copy of the task Smack into value
3666 *
3667 * Returns the length of the smack label or an error code
3668 */
3669static int smack_getprocattr(struct task_struct *p, const char *name, char **value)
3670{
3671 struct smack_known *skp = smk_of_task_struct_obj(p);
3672 char *cp;
3673 int slen;
3674
3675 if (strcmp(name, "current") != 0)
3676 return -EINVAL;
3677
3678 cp = kstrdup(skp->smk_known, GFP_KERNEL);
3679 if (cp == NULL)
3680 return -ENOMEM;
3681
3682 slen = strlen(cp);
3683 *value = cp;
3684 return slen;
3685}
3686
3687/**
3688 * do_setattr - Smack process attribute setting
3689 * @attr: the ID of the attribute
3690 * @value: the value to set
3691 * @size: the size of the value
3692 *
3693 * Sets the Smack value of the task. Only setting self
3694 * is permitted and only with privilege
3695 *
3696 * Returns the length of the smack label or an error code
3697 */
3698static int do_setattr(u64 attr, void *value, size_t size)
3699{
3700 struct task_smack *tsp = smack_cred(current_cred());
3701 struct cred *new;
3702 struct smack_known *skp;
3703 struct smack_known_list_elem *sklep;
3704 int rc;
3705
3706 if (!smack_privileged(CAP_MAC_ADMIN) && list_empty(&tsp->smk_relabel))
3707 return -EPERM;
3708
3709 if (value == NULL || size == 0 || size >= SMK_LONGLABEL)
3710 return -EINVAL;
3711
3712 if (attr != LSM_ATTR_CURRENT)
3713 return -EOPNOTSUPP;
3714
3715 skp = smk_import_entry(value, size);
3716 if (IS_ERR(skp))
3717 return PTR_ERR(skp);
3718
3719 /*
3720 * No process is ever allowed the web ("@") label
3721 * and the star ("*") label.
3722 */
3723 if (skp == &smack_known_web || skp == &smack_known_star)
3724 return -EINVAL;
3725
3726 if (!smack_privileged(CAP_MAC_ADMIN)) {
3727 rc = -EPERM;
3728 list_for_each_entry(sklep, &tsp->smk_relabel, list)
3729 if (sklep->smk_label == skp) {
3730 rc = 0;
3731 break;
3732 }
3733 if (rc)
3734 return rc;
3735 }
3736
3737 new = prepare_creds();
3738 if (new == NULL)
3739 return -ENOMEM;
3740
3741 tsp = smack_cred(new);
3742 tsp->smk_task = skp;
3743 /*
3744 * process can change its label only once
3745 */
3746 smk_destroy_label_list(&tsp->smk_relabel);
3747
3748 commit_creds(new);
3749 return size;
3750}
3751
3752/**
3753 * smack_setselfattr - Set a Smack process attribute
3754 * @attr: which attribute to set
3755 * @ctx: buffer containing the data
3756 * @size: size of @ctx
3757 * @flags: unused
3758 *
3759 * Fill the passed user space @ctx with the details of the requested
3760 * attribute.
3761 *
3762 * Returns 0 on success, an error code otherwise.
3763 */
3764static int smack_setselfattr(unsigned int attr, struct lsm_ctx *ctx,
3765 size_t size, u32 flags)
3766{
3767 int rc;
3768
3769 rc = do_setattr(attr, ctx->ctx, ctx->ctx_len);
3770 if (rc > 0)
3771 return 0;
3772 return rc;
3773}
3774
3775/**
3776 * smack_setprocattr - Smack process attribute setting
3777 * @name: the name of the attribute in /proc/.../attr
3778 * @value: the value to set
3779 * @size: the size of the value
3780 *
3781 * Sets the Smack value of the task. Only setting self
3782 * is permitted and only with privilege
3783 *
3784 * Returns the length of the smack label or an error code
3785 */
3786static int smack_setprocattr(const char *name, void *value, size_t size)
3787{
3788 int attr = lsm_name_to_attr(name);
3789
3790 if (attr != LSM_ATTR_UNDEF)
3791 return do_setattr(attr, value, size);
3792 return -EINVAL;
3793}
3794
3795/**
3796 * smack_unix_stream_connect - Smack access on UDS
3797 * @sock: one sock
3798 * @other: the other sock
3799 * @newsk: unused
3800 *
3801 * Return 0 if a subject with the smack of sock could access
3802 * an object with the smack of other, otherwise an error code
3803 */
3804static int smack_unix_stream_connect(struct sock *sock,
3805 struct sock *other, struct sock *newsk)
3806{
3807 struct smack_known *skp;
3808 struct smack_known *okp;
3809 struct socket_smack *ssp = sock->sk_security;
3810 struct socket_smack *osp = other->sk_security;
3811 struct socket_smack *nsp = newsk->sk_security;
3812 struct smk_audit_info ad;
3813 int rc = 0;
3814#ifdef CONFIG_AUDIT
3815 struct lsm_network_audit net;
3816#endif
3817
3818 if (!smack_privileged(CAP_MAC_OVERRIDE)) {
3819 skp = ssp->smk_out;
3820 okp = osp->smk_in;
3821#ifdef CONFIG_AUDIT
3822 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
3823 smk_ad_setfield_u_net_sk(&ad, other);
3824#endif
3825 rc = smk_access(skp, okp, MAY_WRITE, &ad);
3826 rc = smk_bu_note("UDS connect", skp, okp, MAY_WRITE, rc);
3827 if (rc == 0) {
3828 okp = osp->smk_out;
3829 skp = ssp->smk_in;
3830 rc = smk_access(okp, skp, MAY_WRITE, &ad);
3831 rc = smk_bu_note("UDS connect", okp, skp,
3832 MAY_WRITE, rc);
3833 }
3834 }
3835
3836 /*
3837 * Cross reference the peer labels for SO_PEERSEC.
3838 */
3839 if (rc == 0) {
3840 nsp->smk_packet = ssp->smk_out;
3841 ssp->smk_packet = osp->smk_out;
3842 }
3843
3844 return rc;
3845}
3846
3847/**
3848 * smack_unix_may_send - Smack access on UDS
3849 * @sock: one socket
3850 * @other: the other socket
3851 *
3852 * Return 0 if a subject with the smack of sock could access
3853 * an object with the smack of other, otherwise an error code
3854 */
3855static int smack_unix_may_send(struct socket *sock, struct socket *other)
3856{
3857 struct socket_smack *ssp = sock->sk->sk_security;
3858 struct socket_smack *osp = other->sk->sk_security;
3859 struct smk_audit_info ad;
3860 int rc;
3861
3862#ifdef CONFIG_AUDIT
3863 struct lsm_network_audit net;
3864
3865 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
3866 smk_ad_setfield_u_net_sk(&ad, other->sk);
3867#endif
3868
3869 if (smack_privileged(CAP_MAC_OVERRIDE))
3870 return 0;
3871
3872 rc = smk_access(ssp->smk_out, osp->smk_in, MAY_WRITE, &ad);
3873 rc = smk_bu_note("UDS send", ssp->smk_out, osp->smk_in, MAY_WRITE, rc);
3874 return rc;
3875}
3876
3877/**
3878 * smack_socket_sendmsg - Smack check based on destination host
3879 * @sock: the socket
3880 * @msg: the message
3881 * @size: the size of the message
3882 *
3883 * Return 0 if the current subject can write to the destination host.
3884 * For IPv4 this is only a question if the destination is a single label host.
3885 * For IPv6 this is a check against the label of the port.
3886 */
3887static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3888 int size)
3889{
3890 struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name;
3891#if IS_ENABLED(CONFIG_IPV6)
3892 struct sockaddr_in6 *sap = (struct sockaddr_in6 *) msg->msg_name;
3893#endif
3894#ifdef SMACK_IPV6_SECMARK_LABELING
3895 struct socket_smack *ssp = sock->sk->sk_security;
3896 struct smack_known *rsp;
3897#endif
3898 int rc = 0;
3899
3900 /*
3901 * Perfectly reasonable for this to be NULL
3902 */
3903 if (sip == NULL)
3904 return 0;
3905
3906 switch (sock->sk->sk_family) {
3907 case AF_INET:
3908 if (msg->msg_namelen < sizeof(struct sockaddr_in) ||
3909 sip->sin_family != AF_INET)
3910 return -EINVAL;
3911 rc = smk_ipv4_check(sock->sk, sip);
3912 break;
3913#if IS_ENABLED(CONFIG_IPV6)
3914 case AF_INET6:
3915 if (msg->msg_namelen < SIN6_LEN_RFC2133 ||
3916 sap->sin6_family != AF_INET6)
3917 return -EINVAL;
3918#ifdef SMACK_IPV6_SECMARK_LABELING
3919 rsp = smack_ipv6host_label(sap);
3920 if (rsp != NULL)
3921 rc = smk_ipv6_check(ssp->smk_out, rsp, sap,
3922 SMK_CONNECTING);
3923#endif
3924#ifdef SMACK_IPV6_PORT_LABELING
3925 rc = smk_ipv6_port_check(sock->sk, sap, SMK_SENDING);
3926#endif
3927#endif /* IS_ENABLED(CONFIG_IPV6) */
3928 break;
3929 }
3930 return rc;
3931}
3932
3933/**
3934 * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat pair to smack
3935 * @sap: netlabel secattr
3936 * @ssp: socket security information
3937 *
3938 * Returns a pointer to a Smack label entry found on the label list.
3939 */
3940static struct smack_known *smack_from_secattr(struct netlbl_lsm_secattr *sap,
3941 struct socket_smack *ssp)
3942{
3943 struct smack_known *skp;
3944 int found = 0;
3945 int acat;
3946 int kcat;
3947
3948 /*
3949 * Netlabel found it in the cache.
3950 */
3951 if ((sap->flags & NETLBL_SECATTR_CACHE) != 0)
3952 return (struct smack_known *)sap->cache->data;
3953
3954 if ((sap->flags & NETLBL_SECATTR_SECID) != 0)
3955 /*
3956 * Looks like a fallback, which gives us a secid.
3957 */
3958 return smack_from_secid(sap->attr.secid);
3959
3960 if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) {
3961 /*
3962 * Looks like a CIPSO packet.
3963 * If there are flags but no level netlabel isn't
3964 * behaving the way we expect it to.
3965 *
3966 * Look it up in the label table
3967 * Without guidance regarding the smack value
3968 * for the packet fall back on the network
3969 * ambient value.
3970 */
3971 rcu_read_lock();
3972 list_for_each_entry_rcu(skp, &smack_known_list, list) {
3973 if (sap->attr.mls.lvl != skp->smk_netlabel.attr.mls.lvl)
3974 continue;
3975 /*
3976 * Compare the catsets. Use the netlbl APIs.
3977 */
3978 if ((sap->flags & NETLBL_SECATTR_MLS_CAT) == 0) {
3979 if ((skp->smk_netlabel.flags &
3980 NETLBL_SECATTR_MLS_CAT) == 0)
3981 found = 1;
3982 break;
3983 }
3984 for (acat = -1, kcat = -1; acat == kcat; ) {
3985 acat = netlbl_catmap_walk(sap->attr.mls.cat,
3986 acat + 1);
3987 kcat = netlbl_catmap_walk(
3988 skp->smk_netlabel.attr.mls.cat,
3989 kcat + 1);
3990 if (acat < 0 || kcat < 0)
3991 break;
3992 }
3993 if (acat == kcat) {
3994 found = 1;
3995 break;
3996 }
3997 }
3998 rcu_read_unlock();
3999
4000 if (found)
4001 return skp;
4002
4003 if (ssp != NULL && ssp->smk_in == &smack_known_star)
4004 return &smack_known_web;
4005 return &smack_known_star;
4006 }
4007 /*
4008 * Without guidance regarding the smack value
4009 * for the packet fall back on the network
4010 * ambient value.
4011 */
4012 return smack_net_ambient;
4013}
4014
4015#if IS_ENABLED(CONFIG_IPV6)
4016static int smk_skb_to_addr_ipv6(struct sk_buff *skb, struct sockaddr_in6 *sip)
4017{
4018 u8 nexthdr;
4019 int offset;
4020 int proto = -EINVAL;
4021 struct ipv6hdr _ipv6h;
4022 struct ipv6hdr *ip6;
4023 __be16 frag_off;
4024 struct tcphdr _tcph, *th;
4025 struct udphdr _udph, *uh;
4026 struct dccp_hdr _dccph, *dh;
4027
4028 sip->sin6_port = 0;
4029
4030 offset = skb_network_offset(skb);
4031 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4032 if (ip6 == NULL)
4033 return -EINVAL;
4034 sip->sin6_addr = ip6->saddr;
4035
4036 nexthdr = ip6->nexthdr;
4037 offset += sizeof(_ipv6h);
4038 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4039 if (offset < 0)
4040 return -EINVAL;
4041
4042 proto = nexthdr;
4043 switch (proto) {
4044 case IPPROTO_TCP:
4045 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4046 if (th != NULL)
4047 sip->sin6_port = th->source;
4048 break;
4049 case IPPROTO_UDP:
4050 case IPPROTO_UDPLITE:
4051 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4052 if (uh != NULL)
4053 sip->sin6_port = uh->source;
4054 break;
4055 case IPPROTO_DCCP:
4056 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4057 if (dh != NULL)
4058 sip->sin6_port = dh->dccph_sport;
4059 break;
4060 }
4061 return proto;
4062}
4063#endif /* CONFIG_IPV6 */
4064
4065/**
4066 * smack_from_skb - Smack data from the secmark in an skb
4067 * @skb: packet
4068 *
4069 * Returns smack_known of the secmark or NULL if that won't work.
4070 */
4071#ifdef CONFIG_NETWORK_SECMARK
4072static struct smack_known *smack_from_skb(struct sk_buff *skb)
4073{
4074 if (skb == NULL || skb->secmark == 0)
4075 return NULL;
4076
4077 return smack_from_secid(skb->secmark);
4078}
4079#else
4080static inline struct smack_known *smack_from_skb(struct sk_buff *skb)
4081{
4082 return NULL;
4083}
4084#endif
4085
4086/**
4087 * smack_from_netlbl - Smack data from the IP options in an skb
4088 * @sk: socket data came in on
4089 * @family: address family
4090 * @skb: packet
4091 *
4092 * Find the Smack label in the IP options. If it hasn't been
4093 * added to the netlabel cache, add it here.
4094 *
4095 * Returns smack_known of the IP options or NULL if that won't work.
4096 */
4097static struct smack_known *smack_from_netlbl(const struct sock *sk, u16 family,
4098 struct sk_buff *skb)
4099{
4100 struct netlbl_lsm_secattr secattr;
4101 struct socket_smack *ssp = NULL;
4102 struct smack_known *skp = NULL;
4103
4104 netlbl_secattr_init(&secattr);
4105
4106 if (sk)
4107 ssp = sk->sk_security;
4108
4109 if (netlbl_skbuff_getattr(skb, family, &secattr) == 0) {
4110 skp = smack_from_secattr(&secattr, ssp);
4111 if (secattr.flags & NETLBL_SECATTR_CACHEABLE)
4112 netlbl_cache_add(skb, family, &skp->smk_netlabel);
4113 }
4114
4115 netlbl_secattr_destroy(&secattr);
4116
4117 return skp;
4118}
4119
4120/**
4121 * smack_socket_sock_rcv_skb - Smack packet delivery access check
4122 * @sk: socket
4123 * @skb: packet
4124 *
4125 * Returns 0 if the packet should be delivered, an error code otherwise
4126 */
4127static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4128{
4129 struct socket_smack *ssp = sk->sk_security;
4130 struct smack_known *skp = NULL;
4131 int rc = 0;
4132 struct smk_audit_info ad;
4133 u16 family = sk->sk_family;
4134#ifdef CONFIG_AUDIT
4135 struct lsm_network_audit net;
4136#endif
4137#if IS_ENABLED(CONFIG_IPV6)
4138 struct sockaddr_in6 sadd;
4139 int proto;
4140
4141 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4142 family = PF_INET;
4143#endif /* CONFIG_IPV6 */
4144
4145 switch (family) {
4146 case PF_INET:
4147 /*
4148 * If there is a secmark use it rather than the CIPSO label.
4149 * If there is no secmark fall back to CIPSO.
4150 * The secmark is assumed to reflect policy better.
4151 */
4152 skp = smack_from_skb(skb);
4153 if (skp == NULL) {
4154 skp = smack_from_netlbl(sk, family, skb);
4155 if (skp == NULL)
4156 skp = smack_net_ambient;
4157 }
4158
4159#ifdef CONFIG_AUDIT
4160 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
4161 ad.a.u.net->family = family;
4162 ad.a.u.net->netif = skb->skb_iif;
4163 ipv4_skb_to_auditdata(skb, &ad.a, NULL);
4164#endif
4165 /*
4166 * Receiving a packet requires that the other end
4167 * be able to write here. Read access is not required.
4168 * This is the simplist possible security model
4169 * for networking.
4170 */
4171 rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
4172 rc = smk_bu_note("IPv4 delivery", skp, ssp->smk_in,
4173 MAY_WRITE, rc);
4174 if (rc != 0)
4175 netlbl_skbuff_err(skb, family, rc, 0);
4176 break;
4177#if IS_ENABLED(CONFIG_IPV6)
4178 case PF_INET6:
4179 proto = smk_skb_to_addr_ipv6(skb, &sadd);
4180 if (proto != IPPROTO_UDP && proto != IPPROTO_UDPLITE &&
4181 proto != IPPROTO_TCP && proto != IPPROTO_DCCP)
4182 break;
4183#ifdef SMACK_IPV6_SECMARK_LABELING
4184 skp = smack_from_skb(skb);
4185 if (skp == NULL) {
4186 if (smk_ipv6_localhost(&sadd))
4187 break;
4188 skp = smack_ipv6host_label(&sadd);
4189 if (skp == NULL)
4190 skp = smack_net_ambient;
4191 }
4192#ifdef CONFIG_AUDIT
4193 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
4194 ad.a.u.net->family = family;
4195 ad.a.u.net->netif = skb->skb_iif;
4196 ipv6_skb_to_auditdata(skb, &ad.a, NULL);
4197#endif /* CONFIG_AUDIT */
4198 rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
4199 rc = smk_bu_note("IPv6 delivery", skp, ssp->smk_in,
4200 MAY_WRITE, rc);
4201#endif /* SMACK_IPV6_SECMARK_LABELING */
4202#ifdef SMACK_IPV6_PORT_LABELING
4203 rc = smk_ipv6_port_check(sk, &sadd, SMK_RECEIVING);
4204#endif /* SMACK_IPV6_PORT_LABELING */
4205 if (rc != 0)
4206 icmpv6_send(skb, ICMPV6_DEST_UNREACH,
4207 ICMPV6_ADM_PROHIBITED, 0);
4208 break;
4209#endif /* CONFIG_IPV6 */
4210 }
4211
4212 return rc;
4213}
4214
4215/**
4216 * smack_socket_getpeersec_stream - pull in packet label
4217 * @sock: the socket
4218 * @optval: user's destination
4219 * @optlen: size thereof
4220 * @len: max thereof
4221 *
4222 * returns zero on success, an error code otherwise
4223 */
4224static int smack_socket_getpeersec_stream(struct socket *sock,
4225 sockptr_t optval, sockptr_t optlen,
4226 unsigned int len)
4227{
4228 struct socket_smack *ssp;
4229 char *rcp = "";
4230 u32 slen = 1;
4231 int rc = 0;
4232
4233 ssp = sock->sk->sk_security;
4234 if (ssp->smk_packet != NULL) {
4235 rcp = ssp->smk_packet->smk_known;
4236 slen = strlen(rcp) + 1;
4237 }
4238 if (slen > len) {
4239 rc = -ERANGE;
4240 goto out_len;
4241 }
4242
4243 if (copy_to_sockptr(optval, rcp, slen))
4244 rc = -EFAULT;
4245out_len:
4246 if (copy_to_sockptr(optlen, &slen, sizeof(slen)))
4247 rc = -EFAULT;
4248 return rc;
4249}
4250
4251
4252/**
4253 * smack_socket_getpeersec_dgram - pull in packet label
4254 * @sock: the peer socket
4255 * @skb: packet data
4256 * @secid: pointer to where to put the secid of the packet
4257 *
4258 * Sets the netlabel socket state on sk from parent
4259 */
4260static int smack_socket_getpeersec_dgram(struct socket *sock,
4261 struct sk_buff *skb, u32 *secid)
4262
4263{
4264 struct socket_smack *ssp = NULL;
4265 struct smack_known *skp;
4266 struct sock *sk = NULL;
4267 int family = PF_UNSPEC;
4268 u32 s = 0; /* 0 is the invalid secid */
4269
4270 if (skb != NULL) {
4271 if (skb->protocol == htons(ETH_P_IP))
4272 family = PF_INET;
4273#if IS_ENABLED(CONFIG_IPV6)
4274 else if (skb->protocol == htons(ETH_P_IPV6))
4275 family = PF_INET6;
4276#endif /* CONFIG_IPV6 */
4277 }
4278 if (family == PF_UNSPEC && sock != NULL)
4279 family = sock->sk->sk_family;
4280
4281 switch (family) {
4282 case PF_UNIX:
4283 ssp = sock->sk->sk_security;
4284 s = ssp->smk_out->smk_secid;
4285 break;
4286 case PF_INET:
4287 skp = smack_from_skb(skb);
4288 if (skp) {
4289 s = skp->smk_secid;
4290 break;
4291 }
4292 /*
4293 * Translate what netlabel gave us.
4294 */
4295 if (sock != NULL)
4296 sk = sock->sk;
4297 skp = smack_from_netlbl(sk, family, skb);
4298 if (skp != NULL)
4299 s = skp->smk_secid;
4300 break;
4301 case PF_INET6:
4302#ifdef SMACK_IPV6_SECMARK_LABELING
4303 skp = smack_from_skb(skb);
4304 if (skp)
4305 s = skp->smk_secid;
4306#endif
4307 break;
4308 }
4309 *secid = s;
4310 if (s == 0)
4311 return -EINVAL;
4312 return 0;
4313}
4314
4315/**
4316 * smack_sock_graft - Initialize a newly created socket with an existing sock
4317 * @sk: child sock
4318 * @parent: parent socket
4319 *
4320 * Set the smk_{in,out} state of an existing sock based on the process that
4321 * is creating the new socket.
4322 */
4323static void smack_sock_graft(struct sock *sk, struct socket *parent)
4324{
4325 struct socket_smack *ssp;
4326 struct smack_known *skp = smk_of_current();
4327
4328 if (sk == NULL ||
4329 (sk->sk_family != PF_INET && sk->sk_family != PF_INET6))
4330 return;
4331
4332 ssp = sk->sk_security;
4333 ssp->smk_in = skp;
4334 ssp->smk_out = skp;
4335 /* cssp->smk_packet is already set in smack_inet_csk_clone() */
4336}
4337
4338/**
4339 * smack_inet_conn_request - Smack access check on connect
4340 * @sk: socket involved
4341 * @skb: packet
4342 * @req: unused
4343 *
4344 * Returns 0 if a task with the packet label could write to
4345 * the socket, otherwise an error code
4346 */
4347static int smack_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
4348 struct request_sock *req)
4349{
4350 u16 family = sk->sk_family;
4351 struct smack_known *skp;
4352 struct socket_smack *ssp = sk->sk_security;
4353 struct sockaddr_in addr;
4354 struct iphdr *hdr;
4355 struct smack_known *hskp;
4356 int rc;
4357 struct smk_audit_info ad;
4358#ifdef CONFIG_AUDIT
4359 struct lsm_network_audit net;
4360#endif
4361
4362#if IS_ENABLED(CONFIG_IPV6)
4363 if (family == PF_INET6) {
4364 /*
4365 * Handle mapped IPv4 packets arriving
4366 * via IPv6 sockets. Don't set up netlabel
4367 * processing on IPv6.
4368 */
4369 if (skb->protocol == htons(ETH_P_IP))
4370 family = PF_INET;
4371 else
4372 return 0;
4373 }
4374#endif /* CONFIG_IPV6 */
4375
4376 /*
4377 * If there is a secmark use it rather than the CIPSO label.
4378 * If there is no secmark fall back to CIPSO.
4379 * The secmark is assumed to reflect policy better.
4380 */
4381 skp = smack_from_skb(skb);
4382 if (skp == NULL) {
4383 skp = smack_from_netlbl(sk, family, skb);
4384 if (skp == NULL)
4385 skp = &smack_known_huh;
4386 }
4387
4388#ifdef CONFIG_AUDIT
4389 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
4390 ad.a.u.net->family = family;
4391 ad.a.u.net->netif = skb->skb_iif;
4392 ipv4_skb_to_auditdata(skb, &ad.a, NULL);
4393#endif
4394 /*
4395 * Receiving a packet requires that the other end be able to write
4396 * here. Read access is not required.
4397 */
4398 rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
4399 rc = smk_bu_note("IPv4 connect", skp, ssp->smk_in, MAY_WRITE, rc);
4400 if (rc != 0)
4401 return rc;
4402
4403 /*
4404 * Save the peer's label in the request_sock so we can later setup
4405 * smk_packet in the child socket so that SO_PEERCRED can report it.
4406 */
4407 req->peer_secid = skp->smk_secid;
4408
4409 /*
4410 * We need to decide if we want to label the incoming connection here
4411 * if we do we only need to label the request_sock and the stack will
4412 * propagate the wire-label to the sock when it is created.
4413 */
4414 hdr = ip_hdr(skb);
4415 addr.sin_addr.s_addr = hdr->saddr;
4416 rcu_read_lock();
4417 hskp = smack_ipv4host_label(&addr);
4418 rcu_read_unlock();
4419
4420 if (hskp == NULL)
4421 rc = netlbl_req_setattr(req, &skp->smk_netlabel);
4422 else
4423 netlbl_req_delattr(req);
4424
4425 return rc;
4426}
4427
4428/**
4429 * smack_inet_csk_clone - Copy the connection information to the new socket
4430 * @sk: the new socket
4431 * @req: the connection's request_sock
4432 *
4433 * Transfer the connection's peer label to the newly created socket.
4434 */
4435static void smack_inet_csk_clone(struct sock *sk,
4436 const struct request_sock *req)
4437{
4438 struct socket_smack *ssp = sk->sk_security;
4439 struct smack_known *skp;
4440
4441 if (req->peer_secid != 0) {
4442 skp = smack_from_secid(req->peer_secid);
4443 ssp->smk_packet = skp;
4444 } else
4445 ssp->smk_packet = NULL;
4446}
4447
4448/*
4449 * Key management security hooks
4450 *
4451 * Casey has not tested key support very heavily.
4452 * The permission check is most likely too restrictive.
4453 * If you care about keys please have a look.
4454 */
4455#ifdef CONFIG_KEYS
4456
4457/**
4458 * smack_key_alloc - Set the key security blob
4459 * @key: object
4460 * @cred: the credentials to use
4461 * @flags: unused
4462 *
4463 * No allocation required
4464 *
4465 * Returns 0
4466 */
4467static int smack_key_alloc(struct key *key, const struct cred *cred,
4468 unsigned long flags)
4469{
4470 struct smack_known *skp = smk_of_task(smack_cred(cred));
4471
4472 key->security = skp;
4473 return 0;
4474}
4475
4476/**
4477 * smack_key_free - Clear the key security blob
4478 * @key: the object
4479 *
4480 * Clear the blob pointer
4481 */
4482static void smack_key_free(struct key *key)
4483{
4484 key->security = NULL;
4485}
4486
4487/**
4488 * smack_key_permission - Smack access on a key
4489 * @key_ref: gets to the object
4490 * @cred: the credentials to use
4491 * @need_perm: requested key permission
4492 *
4493 * Return 0 if the task has read and write to the object,
4494 * an error code otherwise
4495 */
4496static int smack_key_permission(key_ref_t key_ref,
4497 const struct cred *cred,
4498 enum key_need_perm need_perm)
4499{
4500 struct key *keyp;
4501 struct smk_audit_info ad;
4502 struct smack_known *tkp = smk_of_task(smack_cred(cred));
4503 int request = 0;
4504 int rc;
4505
4506 /*
4507 * Validate requested permissions
4508 */
4509 switch (need_perm) {
4510 case KEY_NEED_READ:
4511 case KEY_NEED_SEARCH:
4512 case KEY_NEED_VIEW:
4513 request |= MAY_READ;
4514 break;
4515 case KEY_NEED_WRITE:
4516 case KEY_NEED_LINK:
4517 case KEY_NEED_SETATTR:
4518 request |= MAY_WRITE;
4519 break;
4520 case KEY_NEED_UNSPECIFIED:
4521 case KEY_NEED_UNLINK:
4522 case KEY_SYSADMIN_OVERRIDE:
4523 case KEY_AUTHTOKEN_OVERRIDE:
4524 case KEY_DEFER_PERM_CHECK:
4525 return 0;
4526 default:
4527 return -EINVAL;
4528 }
4529
4530 keyp = key_ref_to_ptr(key_ref);
4531 if (keyp == NULL)
4532 return -EINVAL;
4533 /*
4534 * If the key hasn't been initialized give it access so that
4535 * it may do so.
4536 */
4537 if (keyp->security == NULL)
4538 return 0;
4539 /*
4540 * This should not occur
4541 */
4542 if (tkp == NULL)
4543 return -EACCES;
4544
4545 if (smack_privileged(CAP_MAC_OVERRIDE))
4546 return 0;
4547
4548#ifdef CONFIG_AUDIT
4549 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY);
4550 ad.a.u.key_struct.key = keyp->serial;
4551 ad.a.u.key_struct.key_desc = keyp->description;
4552#endif
4553 rc = smk_access(tkp, keyp->security, request, &ad);
4554 rc = smk_bu_note("key access", tkp, keyp->security, request, rc);
4555 return rc;
4556}
4557
4558/*
4559 * smack_key_getsecurity - Smack label tagging the key
4560 * @key points to the key to be queried
4561 * @_buffer points to a pointer that should be set to point to the
4562 * resulting string (if no label or an error occurs).
4563 * Return the length of the string (including terminating NUL) or -ve if
4564 * an error.
4565 * May also return 0 (and a NULL buffer pointer) if there is no label.
4566 */
4567static int smack_key_getsecurity(struct key *key, char **_buffer)
4568{
4569 struct smack_known *skp = key->security;
4570 size_t length;
4571 char *copy;
4572
4573 if (key->security == NULL) {
4574 *_buffer = NULL;
4575 return 0;
4576 }
4577
4578 copy = kstrdup(skp->smk_known, GFP_KERNEL);
4579 if (copy == NULL)
4580 return -ENOMEM;
4581 length = strlen(copy) + 1;
4582
4583 *_buffer = copy;
4584 return length;
4585}
4586
4587
4588#ifdef CONFIG_KEY_NOTIFICATIONS
4589/**
4590 * smack_watch_key - Smack access to watch a key for notifications.
4591 * @key: The key to be watched
4592 *
4593 * Return 0 if the @watch->cred has permission to read from the key object and
4594 * an error otherwise.
4595 */
4596static int smack_watch_key(struct key *key)
4597{
4598 struct smk_audit_info ad;
4599 struct smack_known *tkp = smk_of_current();
4600 int rc;
4601
4602 if (key == NULL)
4603 return -EINVAL;
4604 /*
4605 * If the key hasn't been initialized give it access so that
4606 * it may do so.
4607 */
4608 if (key->security == NULL)
4609 return 0;
4610 /*
4611 * This should not occur
4612 */
4613 if (tkp == NULL)
4614 return -EACCES;
4615
4616 if (smack_privileged_cred(CAP_MAC_OVERRIDE, current_cred()))
4617 return 0;
4618
4619#ifdef CONFIG_AUDIT
4620 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY);
4621 ad.a.u.key_struct.key = key->serial;
4622 ad.a.u.key_struct.key_desc = key->description;
4623#endif
4624 rc = smk_access(tkp, key->security, MAY_READ, &ad);
4625 rc = smk_bu_note("key watch", tkp, key->security, MAY_READ, rc);
4626 return rc;
4627}
4628#endif /* CONFIG_KEY_NOTIFICATIONS */
4629#endif /* CONFIG_KEYS */
4630
4631#ifdef CONFIG_WATCH_QUEUE
4632/**
4633 * smack_post_notification - Smack access to post a notification to a queue
4634 * @w_cred: The credentials of the watcher.
4635 * @cred: The credentials of the event source (may be NULL).
4636 * @n: The notification message to be posted.
4637 */
4638static int smack_post_notification(const struct cred *w_cred,
4639 const struct cred *cred,
4640 struct watch_notification *n)
4641{
4642 struct smk_audit_info ad;
4643 struct smack_known *subj, *obj;
4644 int rc;
4645
4646 /* Always let maintenance notifications through. */
4647 if (n->type == WATCH_TYPE_META)
4648 return 0;
4649
4650 if (!cred)
4651 return 0;
4652 subj = smk_of_task(smack_cred(cred));
4653 obj = smk_of_task(smack_cred(w_cred));
4654
4655 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NOTIFICATION);
4656 rc = smk_access(subj, obj, MAY_WRITE, &ad);
4657 rc = smk_bu_note("notification", subj, obj, MAY_WRITE, rc);
4658 return rc;
4659}
4660#endif /* CONFIG_WATCH_QUEUE */
4661
4662/*
4663 * Smack Audit hooks
4664 *
4665 * Audit requires a unique representation of each Smack specific
4666 * rule. This unique representation is used to distinguish the
4667 * object to be audited from remaining kernel objects and also
4668 * works as a glue between the audit hooks.
4669 *
4670 * Since repository entries are added but never deleted, we'll use
4671 * the smack_known label address related to the given audit rule as
4672 * the needed unique representation. This also better fits the smack
4673 * model where nearly everything is a label.
4674 */
4675#ifdef CONFIG_AUDIT
4676
4677/**
4678 * smack_audit_rule_init - Initialize a smack audit rule
4679 * @field: audit rule fields given from user-space (audit.h)
4680 * @op: required testing operator (=, !=, >, <, ...)
4681 * @rulestr: smack label to be audited
4682 * @vrule: pointer to save our own audit rule representation
4683 *
4684 * Prepare to audit cases where (@field @op @rulestr) is true.
4685 * The label to be audited is created if necessay.
4686 */
4687static int smack_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
4688{
4689 struct smack_known *skp;
4690 char **rule = (char **)vrule;
4691 *rule = NULL;
4692
4693 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
4694 return -EINVAL;
4695
4696 if (op != Audit_equal && op != Audit_not_equal)
4697 return -EINVAL;
4698
4699 skp = smk_import_entry(rulestr, 0);
4700 if (IS_ERR(skp))
4701 return PTR_ERR(skp);
4702
4703 *rule = skp->smk_known;
4704
4705 return 0;
4706}
4707
4708/**
4709 * smack_audit_rule_known - Distinguish Smack audit rules
4710 * @krule: rule of interest, in Audit kernel representation format
4711 *
4712 * This is used to filter Smack rules from remaining Audit ones.
4713 * If it's proved that this rule belongs to us, the
4714 * audit_rule_match hook will be called to do the final judgement.
4715 */
4716static int smack_audit_rule_known(struct audit_krule *krule)
4717{
4718 struct audit_field *f;
4719 int i;
4720
4721 for (i = 0; i < krule->field_count; i++) {
4722 f = &krule->fields[i];
4723
4724 if (f->type == AUDIT_SUBJ_USER || f->type == AUDIT_OBJ_USER)
4725 return 1;
4726 }
4727
4728 return 0;
4729}
4730
4731/**
4732 * smack_audit_rule_match - Audit given object ?
4733 * @secid: security id for identifying the object to test
4734 * @field: audit rule flags given from user-space
4735 * @op: required testing operator
4736 * @vrule: smack internal rule presentation
4737 *
4738 * The core Audit hook. It's used to take the decision of
4739 * whether to audit or not to audit a given object.
4740 */
4741static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule)
4742{
4743 struct smack_known *skp;
4744 char *rule = vrule;
4745
4746 if (unlikely(!rule)) {
4747 WARN_ONCE(1, "Smack: missing rule\n");
4748 return -ENOENT;
4749 }
4750
4751 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
4752 return 0;
4753
4754 skp = smack_from_secid(secid);
4755
4756 /*
4757 * No need to do string comparisons. If a match occurs,
4758 * both pointers will point to the same smack_known
4759 * label.
4760 */
4761 if (op == Audit_equal)
4762 return (rule == skp->smk_known);
4763 if (op == Audit_not_equal)
4764 return (rule != skp->smk_known);
4765
4766 return 0;
4767}
4768
4769/*
4770 * There is no need for a smack_audit_rule_free hook.
4771 * No memory was allocated.
4772 */
4773
4774#endif /* CONFIG_AUDIT */
4775
4776/**
4777 * smack_ismaclabel - check if xattr @name references a smack MAC label
4778 * @name: Full xattr name to check.
4779 */
4780static int smack_ismaclabel(const char *name)
4781{
4782 return (strcmp(name, XATTR_SMACK_SUFFIX) == 0);
4783}
4784
4785
4786/**
4787 * smack_secid_to_secctx - return the smack label for a secid
4788 * @secid: incoming integer
4789 * @secdata: destination
4790 * @seclen: how long it is
4791 *
4792 * Exists for networking code.
4793 */
4794static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
4795{
4796 struct smack_known *skp = smack_from_secid(secid);
4797
4798 if (secdata)
4799 *secdata = skp->smk_known;
4800 *seclen = strlen(skp->smk_known);
4801 return 0;
4802}
4803
4804/**
4805 * smack_secctx_to_secid - return the secid for a smack label
4806 * @secdata: smack label
4807 * @seclen: how long result is
4808 * @secid: outgoing integer
4809 *
4810 * Exists for audit and networking code.
4811 */
4812static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
4813{
4814 struct smack_known *skp = smk_find_entry(secdata);
4815
4816 if (skp)
4817 *secid = skp->smk_secid;
4818 else
4819 *secid = 0;
4820 return 0;
4821}
4822
4823/*
4824 * There used to be a smack_release_secctx hook
4825 * that did nothing back when hooks were in a vector.
4826 * Now that there's a list such a hook adds cost.
4827 */
4828
4829static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
4830{
4831 return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx,
4832 ctxlen, 0);
4833}
4834
4835static int smack_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
4836{
4837 return __vfs_setxattr_noperm(&nop_mnt_idmap, dentry, XATTR_NAME_SMACK,
4838 ctx, ctxlen, 0);
4839}
4840
4841static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
4842{
4843 struct smack_known *skp = smk_of_inode(inode);
4844
4845 *ctx = skp->smk_known;
4846 *ctxlen = strlen(skp->smk_known);
4847 return 0;
4848}
4849
4850static int smack_inode_copy_up(struct dentry *dentry, struct cred **new)
4851{
4852
4853 struct task_smack *tsp;
4854 struct smack_known *skp;
4855 struct inode_smack *isp;
4856 struct cred *new_creds = *new;
4857
4858 if (new_creds == NULL) {
4859 new_creds = prepare_creds();
4860 if (new_creds == NULL)
4861 return -ENOMEM;
4862 }
4863
4864 tsp = smack_cred(new_creds);
4865
4866 /*
4867 * Get label from overlay inode and set it in create_sid
4868 */
4869 isp = smack_inode(d_inode(dentry));
4870 skp = isp->smk_inode;
4871 tsp->smk_task = skp;
4872 *new = new_creds;
4873 return 0;
4874}
4875
4876static int smack_inode_copy_up_xattr(const char *name)
4877{
4878 /*
4879 * Return 1 if this is the smack access Smack attribute.
4880 */
4881 if (strcmp(name, XATTR_NAME_SMACK) == 0)
4882 return 1;
4883
4884 return -EOPNOTSUPP;
4885}
4886
4887static int smack_dentry_create_files_as(struct dentry *dentry, int mode,
4888 struct qstr *name,
4889 const struct cred *old,
4890 struct cred *new)
4891{
4892 struct task_smack *otsp = smack_cred(old);
4893 struct task_smack *ntsp = smack_cred(new);
4894 struct inode_smack *isp;
4895 int may;
4896
4897 /*
4898 * Use the process credential unless all of
4899 * the transmuting criteria are met
4900 */
4901 ntsp->smk_task = otsp->smk_task;
4902
4903 /*
4904 * the attribute of the containing directory
4905 */
4906 isp = smack_inode(d_inode(dentry->d_parent));
4907
4908 if (isp->smk_flags & SMK_INODE_TRANSMUTE) {
4909 rcu_read_lock();
4910 may = smk_access_entry(otsp->smk_task->smk_known,
4911 isp->smk_inode->smk_known,
4912 &otsp->smk_task->smk_rules);
4913 rcu_read_unlock();
4914
4915 /*
4916 * If the directory is transmuting and the rule
4917 * providing access is transmuting use the containing
4918 * directory label instead of the process label.
4919 */
4920 if (may > 0 && (may & MAY_TRANSMUTE)) {
4921 ntsp->smk_task = isp->smk_inode;
4922 ntsp->smk_transmuted = ntsp->smk_task;
4923 }
4924 }
4925 return 0;
4926}
4927
4928#ifdef CONFIG_IO_URING
4929/**
4930 * smack_uring_override_creds - Is io_uring cred override allowed?
4931 * @new: the target creds
4932 *
4933 * Check to see if the current task is allowed to override it's credentials
4934 * to service an io_uring operation.
4935 */
4936static int smack_uring_override_creds(const struct cred *new)
4937{
4938 struct task_smack *tsp = smack_cred(current_cred());
4939 struct task_smack *nsp = smack_cred(new);
4940
4941 /*
4942 * Allow the degenerate case where the new Smack value is
4943 * the same as the current Smack value.
4944 */
4945 if (tsp->smk_task == nsp->smk_task)
4946 return 0;
4947
4948 if (smack_privileged_cred(CAP_MAC_OVERRIDE, current_cred()))
4949 return 0;
4950
4951 return -EPERM;
4952}
4953
4954/**
4955 * smack_uring_sqpoll - check if a io_uring polling thread can be created
4956 *
4957 * Check to see if the current task is allowed to create a new io_uring
4958 * kernel polling thread.
4959 */
4960static int smack_uring_sqpoll(void)
4961{
4962 if (smack_privileged_cred(CAP_MAC_ADMIN, current_cred()))
4963 return 0;
4964
4965 return -EPERM;
4966}
4967
4968/**
4969 * smack_uring_cmd - check on file operations for io_uring
4970 * @ioucmd: the command in question
4971 *
4972 * Make a best guess about whether a io_uring "command" should
4973 * be allowed. Use the same logic used for determining if the
4974 * file could be opened for read in the absence of better criteria.
4975 */
4976static int smack_uring_cmd(struct io_uring_cmd *ioucmd)
4977{
4978 struct file *file = ioucmd->file;
4979 struct smk_audit_info ad;
4980 struct task_smack *tsp;
4981 struct inode *inode;
4982 int rc;
4983
4984 if (!file)
4985 return -EINVAL;
4986
4987 tsp = smack_cred(file->f_cred);
4988 inode = file_inode(file);
4989
4990 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
4991 smk_ad_setfield_u_fs_path(&ad, file->f_path);
4992 rc = smk_tskacc(tsp, smk_of_inode(inode), MAY_READ, &ad);
4993 rc = smk_bu_credfile(file->f_cred, file, MAY_READ, rc);
4994
4995 return rc;
4996}
4997
4998#endif /* CONFIG_IO_URING */
4999
5000struct lsm_blob_sizes smack_blob_sizes __ro_after_init = {
5001 .lbs_cred = sizeof(struct task_smack),
5002 .lbs_file = sizeof(struct smack_known *),
5003 .lbs_inode = sizeof(struct inode_smack),
5004 .lbs_ipc = sizeof(struct smack_known *),
5005 .lbs_msg_msg = sizeof(struct smack_known *),
5006 .lbs_superblock = sizeof(struct superblock_smack),
5007 .lbs_xattr_count = SMACK_INODE_INIT_XATTRS,
5008};
5009
5010static const struct lsm_id smack_lsmid = {
5011 .name = "smack",
5012 .id = LSM_ID_SMACK,
5013};
5014
5015static struct security_hook_list smack_hooks[] __ro_after_init = {
5016 LSM_HOOK_INIT(ptrace_access_check, smack_ptrace_access_check),
5017 LSM_HOOK_INIT(ptrace_traceme, smack_ptrace_traceme),
5018 LSM_HOOK_INIT(syslog, smack_syslog),
5019
5020 LSM_HOOK_INIT(fs_context_submount, smack_fs_context_submount),
5021 LSM_HOOK_INIT(fs_context_dup, smack_fs_context_dup),
5022 LSM_HOOK_INIT(fs_context_parse_param, smack_fs_context_parse_param),
5023
5024 LSM_HOOK_INIT(sb_alloc_security, smack_sb_alloc_security),
5025 LSM_HOOK_INIT(sb_free_mnt_opts, smack_free_mnt_opts),
5026 LSM_HOOK_INIT(sb_eat_lsm_opts, smack_sb_eat_lsm_opts),
5027 LSM_HOOK_INIT(sb_statfs, smack_sb_statfs),
5028 LSM_HOOK_INIT(sb_set_mnt_opts, smack_set_mnt_opts),
5029
5030 LSM_HOOK_INIT(bprm_creds_for_exec, smack_bprm_creds_for_exec),
5031
5032 LSM_HOOK_INIT(inode_alloc_security, smack_inode_alloc_security),
5033 LSM_HOOK_INIT(inode_init_security, smack_inode_init_security),
5034 LSM_HOOK_INIT(inode_link, smack_inode_link),
5035 LSM_HOOK_INIT(inode_unlink, smack_inode_unlink),
5036 LSM_HOOK_INIT(inode_rmdir, smack_inode_rmdir),
5037 LSM_HOOK_INIT(inode_rename, smack_inode_rename),
5038 LSM_HOOK_INIT(inode_permission, smack_inode_permission),
5039 LSM_HOOK_INIT(inode_setattr, smack_inode_setattr),
5040 LSM_HOOK_INIT(inode_getattr, smack_inode_getattr),
5041 LSM_HOOK_INIT(inode_setxattr, smack_inode_setxattr),
5042 LSM_HOOK_INIT(inode_post_setxattr, smack_inode_post_setxattr),
5043 LSM_HOOK_INIT(inode_getxattr, smack_inode_getxattr),
5044 LSM_HOOK_INIT(inode_removexattr, smack_inode_removexattr),
5045 LSM_HOOK_INIT(inode_set_acl, smack_inode_set_acl),
5046 LSM_HOOK_INIT(inode_get_acl, smack_inode_get_acl),
5047 LSM_HOOK_INIT(inode_remove_acl, smack_inode_remove_acl),
5048 LSM_HOOK_INIT(inode_getsecurity, smack_inode_getsecurity),
5049 LSM_HOOK_INIT(inode_setsecurity, smack_inode_setsecurity),
5050 LSM_HOOK_INIT(inode_listsecurity, smack_inode_listsecurity),
5051 LSM_HOOK_INIT(inode_getsecid, smack_inode_getsecid),
5052
5053 LSM_HOOK_INIT(file_alloc_security, smack_file_alloc_security),
5054 LSM_HOOK_INIT(file_ioctl, smack_file_ioctl),
5055 LSM_HOOK_INIT(file_ioctl_compat, smack_file_ioctl),
5056 LSM_HOOK_INIT(file_lock, smack_file_lock),
5057 LSM_HOOK_INIT(file_fcntl, smack_file_fcntl),
5058 LSM_HOOK_INIT(mmap_file, smack_mmap_file),
5059 LSM_HOOK_INIT(mmap_addr, cap_mmap_addr),
5060 LSM_HOOK_INIT(file_set_fowner, smack_file_set_fowner),
5061 LSM_HOOK_INIT(file_send_sigiotask, smack_file_send_sigiotask),
5062 LSM_HOOK_INIT(file_receive, smack_file_receive),
5063
5064 LSM_HOOK_INIT(file_open, smack_file_open),
5065
5066 LSM_HOOK_INIT(cred_alloc_blank, smack_cred_alloc_blank),
5067 LSM_HOOK_INIT(cred_free, smack_cred_free),
5068 LSM_HOOK_INIT(cred_prepare, smack_cred_prepare),
5069 LSM_HOOK_INIT(cred_transfer, smack_cred_transfer),
5070 LSM_HOOK_INIT(cred_getsecid, smack_cred_getsecid),
5071 LSM_HOOK_INIT(kernel_act_as, smack_kernel_act_as),
5072 LSM_HOOK_INIT(kernel_create_files_as, smack_kernel_create_files_as),
5073 LSM_HOOK_INIT(task_setpgid, smack_task_setpgid),
5074 LSM_HOOK_INIT(task_getpgid, smack_task_getpgid),
5075 LSM_HOOK_INIT(task_getsid, smack_task_getsid),
5076 LSM_HOOK_INIT(current_getsecid_subj, smack_current_getsecid_subj),
5077 LSM_HOOK_INIT(task_getsecid_obj, smack_task_getsecid_obj),
5078 LSM_HOOK_INIT(task_setnice, smack_task_setnice),
5079 LSM_HOOK_INIT(task_setioprio, smack_task_setioprio),
5080 LSM_HOOK_INIT(task_getioprio, smack_task_getioprio),
5081 LSM_HOOK_INIT(task_setscheduler, smack_task_setscheduler),
5082 LSM_HOOK_INIT(task_getscheduler, smack_task_getscheduler),
5083 LSM_HOOK_INIT(task_movememory, smack_task_movememory),
5084 LSM_HOOK_INIT(task_kill, smack_task_kill),
5085 LSM_HOOK_INIT(task_to_inode, smack_task_to_inode),
5086
5087 LSM_HOOK_INIT(ipc_permission, smack_ipc_permission),
5088 LSM_HOOK_INIT(ipc_getsecid, smack_ipc_getsecid),
5089
5090 LSM_HOOK_INIT(msg_msg_alloc_security, smack_msg_msg_alloc_security),
5091
5092 LSM_HOOK_INIT(msg_queue_alloc_security, smack_ipc_alloc_security),
5093 LSM_HOOK_INIT(msg_queue_associate, smack_msg_queue_associate),
5094 LSM_HOOK_INIT(msg_queue_msgctl, smack_msg_queue_msgctl),
5095 LSM_HOOK_INIT(msg_queue_msgsnd, smack_msg_queue_msgsnd),
5096 LSM_HOOK_INIT(msg_queue_msgrcv, smack_msg_queue_msgrcv),
5097
5098 LSM_HOOK_INIT(shm_alloc_security, smack_ipc_alloc_security),
5099 LSM_HOOK_INIT(shm_associate, smack_shm_associate),
5100 LSM_HOOK_INIT(shm_shmctl, smack_shm_shmctl),
5101 LSM_HOOK_INIT(shm_shmat, smack_shm_shmat),
5102
5103 LSM_HOOK_INIT(sem_alloc_security, smack_ipc_alloc_security),
5104 LSM_HOOK_INIT(sem_associate, smack_sem_associate),
5105 LSM_HOOK_INIT(sem_semctl, smack_sem_semctl),
5106 LSM_HOOK_INIT(sem_semop, smack_sem_semop),
5107
5108 LSM_HOOK_INIT(d_instantiate, smack_d_instantiate),
5109
5110 LSM_HOOK_INIT(getselfattr, smack_getselfattr),
5111 LSM_HOOK_INIT(setselfattr, smack_setselfattr),
5112 LSM_HOOK_INIT(getprocattr, smack_getprocattr),
5113 LSM_HOOK_INIT(setprocattr, smack_setprocattr),
5114
5115 LSM_HOOK_INIT(unix_stream_connect, smack_unix_stream_connect),
5116 LSM_HOOK_INIT(unix_may_send, smack_unix_may_send),
5117
5118 LSM_HOOK_INIT(socket_post_create, smack_socket_post_create),
5119 LSM_HOOK_INIT(socket_socketpair, smack_socket_socketpair),
5120#ifdef SMACK_IPV6_PORT_LABELING
5121 LSM_HOOK_INIT(socket_bind, smack_socket_bind),
5122#endif
5123 LSM_HOOK_INIT(socket_connect, smack_socket_connect),
5124 LSM_HOOK_INIT(socket_sendmsg, smack_socket_sendmsg),
5125 LSM_HOOK_INIT(socket_sock_rcv_skb, smack_socket_sock_rcv_skb),
5126 LSM_HOOK_INIT(socket_getpeersec_stream, smack_socket_getpeersec_stream),
5127 LSM_HOOK_INIT(socket_getpeersec_dgram, smack_socket_getpeersec_dgram),
5128 LSM_HOOK_INIT(sk_alloc_security, smack_sk_alloc_security),
5129 LSM_HOOK_INIT(sk_free_security, smack_sk_free_security),
5130 LSM_HOOK_INIT(sk_clone_security, smack_sk_clone_security),
5131 LSM_HOOK_INIT(sock_graft, smack_sock_graft),
5132 LSM_HOOK_INIT(inet_conn_request, smack_inet_conn_request),
5133 LSM_HOOK_INIT(inet_csk_clone, smack_inet_csk_clone),
5134
5135 /* key management security hooks */
5136#ifdef CONFIG_KEYS
5137 LSM_HOOK_INIT(key_alloc, smack_key_alloc),
5138 LSM_HOOK_INIT(key_free, smack_key_free),
5139 LSM_HOOK_INIT(key_permission, smack_key_permission),
5140 LSM_HOOK_INIT(key_getsecurity, smack_key_getsecurity),
5141#ifdef CONFIG_KEY_NOTIFICATIONS
5142 LSM_HOOK_INIT(watch_key, smack_watch_key),
5143#endif
5144#endif /* CONFIG_KEYS */
5145
5146#ifdef CONFIG_WATCH_QUEUE
5147 LSM_HOOK_INIT(post_notification, smack_post_notification),
5148#endif
5149
5150 /* Audit hooks */
5151#ifdef CONFIG_AUDIT
5152 LSM_HOOK_INIT(audit_rule_init, smack_audit_rule_init),
5153 LSM_HOOK_INIT(audit_rule_known, smack_audit_rule_known),
5154 LSM_HOOK_INIT(audit_rule_match, smack_audit_rule_match),
5155#endif /* CONFIG_AUDIT */
5156
5157 LSM_HOOK_INIT(ismaclabel, smack_ismaclabel),
5158 LSM_HOOK_INIT(secid_to_secctx, smack_secid_to_secctx),
5159 LSM_HOOK_INIT(secctx_to_secid, smack_secctx_to_secid),
5160 LSM_HOOK_INIT(inode_notifysecctx, smack_inode_notifysecctx),
5161 LSM_HOOK_INIT(inode_setsecctx, smack_inode_setsecctx),
5162 LSM_HOOK_INIT(inode_getsecctx, smack_inode_getsecctx),
5163 LSM_HOOK_INIT(inode_copy_up, smack_inode_copy_up),
5164 LSM_HOOK_INIT(inode_copy_up_xattr, smack_inode_copy_up_xattr),
5165 LSM_HOOK_INIT(dentry_create_files_as, smack_dentry_create_files_as),
5166#ifdef CONFIG_IO_URING
5167 LSM_HOOK_INIT(uring_override_creds, smack_uring_override_creds),
5168 LSM_HOOK_INIT(uring_sqpoll, smack_uring_sqpoll),
5169 LSM_HOOK_INIT(uring_cmd, smack_uring_cmd),
5170#endif
5171};
5172
5173
5174static __init void init_smack_known_list(void)
5175{
5176 /*
5177 * Initialize rule list locks
5178 */
5179 mutex_init(&smack_known_huh.smk_rules_lock);
5180 mutex_init(&smack_known_hat.smk_rules_lock);
5181 mutex_init(&smack_known_floor.smk_rules_lock);
5182 mutex_init(&smack_known_star.smk_rules_lock);
5183 mutex_init(&smack_known_web.smk_rules_lock);
5184 /*
5185 * Initialize rule lists
5186 */
5187 INIT_LIST_HEAD(&smack_known_huh.smk_rules);
5188 INIT_LIST_HEAD(&smack_known_hat.smk_rules);
5189 INIT_LIST_HEAD(&smack_known_star.smk_rules);
5190 INIT_LIST_HEAD(&smack_known_floor.smk_rules);
5191 INIT_LIST_HEAD(&smack_known_web.smk_rules);
5192 /*
5193 * Create the known labels list
5194 */
5195 smk_insert_entry(&smack_known_huh);
5196 smk_insert_entry(&smack_known_hat);
5197 smk_insert_entry(&smack_known_star);
5198 smk_insert_entry(&smack_known_floor);
5199 smk_insert_entry(&smack_known_web);
5200}
5201
5202/**
5203 * smack_init - initialize the smack system
5204 *
5205 * Returns 0 on success, -ENOMEM is there's no memory
5206 */
5207static __init int smack_init(void)
5208{
5209 struct cred *cred = (struct cred *) current->cred;
5210 struct task_smack *tsp;
5211
5212 smack_rule_cache = KMEM_CACHE(smack_rule, 0);
5213 if (!smack_rule_cache)
5214 return -ENOMEM;
5215
5216 /*
5217 * Set the security state for the initial task.
5218 */
5219 tsp = smack_cred(cred);
5220 init_task_smack(tsp, &smack_known_floor, &smack_known_floor);
5221
5222 /*
5223 * Register with LSM
5224 */
5225 security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks), &smack_lsmid);
5226 smack_enabled = 1;
5227
5228 pr_info("Smack: Initializing.\n");
5229#ifdef CONFIG_SECURITY_SMACK_NETFILTER
5230 pr_info("Smack: Netfilter enabled.\n");
5231#endif
5232#ifdef SMACK_IPV6_PORT_LABELING
5233 pr_info("Smack: IPv6 port labeling enabled.\n");
5234#endif
5235#ifdef SMACK_IPV6_SECMARK_LABELING
5236 pr_info("Smack: IPv6 Netfilter enabled.\n");
5237#endif
5238
5239 /* initialize the smack_known_list */
5240 init_smack_known_list();
5241
5242 return 0;
5243}
5244
5245/*
5246 * Smack requires early initialization in order to label
5247 * all processes and objects when they are created.
5248 */
5249DEFINE_LSM(smack) = {
5250 .name = "smack",
5251 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
5252 .blobs = &smack_blob_sizes,
5253 .init = smack_init,
5254};