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