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
55 static LIST_HEAD(smk_ipv6_port_list);
56 #endif
57 static struct kmem_cache *smack_inode_cache;
58 int smack_enabled;
59
60 static 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
70 static 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
smk_bu_mode(int mode,char * s)77 static 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
smk_bu_note(char * note,struct smack_known * sskp,struct smack_known * oskp,int mode,int rc)100 static 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
smk_bu_current(char * note,struct smack_known * oskp,int mode,int rc)120 static 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
smk_bu_task(struct task_struct * otp,int mode,int rc)142 static 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
smk_bu_inode(struct inode * inode,int mode,int rc)164 static 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
smk_bu_file(struct file * file,int mode,int rc)194 static 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
smk_bu_credfile(const struct cred * cred,struct file * file,int mode,int rc)223 static 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 */
smk_fetch(const char * name,struct inode * ip,struct dentry * dp)261 static 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_opflags & IOP_XATTR))
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 = __vfs_getxattr(dp, ip, 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 */
new_inode_smack(struct smack_known * skp)294 static 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 */
new_task_smack(struct smack_known * task,struct smack_known * forked,gfp_t gfp)317 static 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 */
smk_copy_rules(struct list_head * nhead,struct list_head * ohead,gfp_t gfp)343 static 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 */
smk_copy_relabel(struct list_head * nhead,struct list_head * ohead,gfp_t gfp)372 static 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 */
smk_ptrace_mode(unsigned int mode)399 static 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 */
smk_ptrace_rule_check(struct task_struct * tracer,struct smack_known * tracee_known,unsigned int mode,const char * func)418 static 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 */
smack_ptrace_access_check(struct task_struct * ctp,unsigned int mode)479 static 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 */
smack_ptrace_traceme(struct task_struct * ptp)496 static 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 */
smack_syslog(int typefrom_file)513 static 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 */
smack_sb_alloc_security(struct super_block * sb)538 static 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_SB_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 */
smack_sb_free_security(struct super_block * sb)564 static 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 */
smack_sb_copy_data(char * orig,char * smackopts)580 static 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 */
smack_parse_opts_str(char * options,struct security_mnt_opts * opts)626 static 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
730 out_opt_err:
731 rc = -EINVAL;
732 pr_warn("Smack: duplicate mount options\n");
733
734 out_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 */
smack_set_mnt_opts(struct super_block * sb,struct security_mnt_opts * opts,unsigned long kern_flags,unsigned long * set_kern_flags)755 static 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_flags & SMK_SB_INITIALIZED)
770 return 0;
771
772 sp->smk_flags |= SMK_SB_INITIALIZED;
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 * For a handful of fs types with no user-controlled
826 * backing store it's okay to trust security labels
827 * in the filesystem. The rest are untrusted.
828 */
829 if (sb->s_user_ns != &init_user_ns &&
830 sb->s_magic != SYSFS_MAGIC && sb->s_magic != TMPFS_MAGIC &&
831 sb->s_magic != RAMFS_MAGIC) {
832 transmute = 1;
833 sp->smk_flags |= SMK_SB_UNTRUSTED;
834 }
835 }
836
837 /*
838 * Initialize the root inode.
839 */
840 isp = inode->i_security;
841 if (isp == NULL) {
842 isp = new_inode_smack(sp->smk_root);
843 if (isp == NULL)
844 return -ENOMEM;
845 inode->i_security = isp;
846 } else
847 isp->smk_inode = sp->smk_root;
848
849 if (transmute)
850 isp->smk_flags |= SMK_INODE_TRANSMUTE;
851
852 return 0;
853 }
854
855 /**
856 * smack_sb_kern_mount - Smack specific mount processing
857 * @sb: the file system superblock
858 * @flags: the mount flags
859 * @data: the smack mount options
860 *
861 * Returns 0 on success, an error code on failure
862 */
smack_sb_kern_mount(struct super_block * sb,int flags,void * data)863 static int smack_sb_kern_mount(struct super_block *sb, int flags, void *data)
864 {
865 int rc = 0;
866 char *options = data;
867 struct security_mnt_opts opts;
868
869 security_init_mnt_opts(&opts);
870
871 if (!options)
872 goto out;
873
874 rc = smack_parse_opts_str(options, &opts);
875 if (rc)
876 goto out_err;
877
878 out:
879 rc = smack_set_mnt_opts(sb, &opts, 0, NULL);
880
881 out_err:
882 security_free_mnt_opts(&opts);
883 return rc;
884 }
885
886 /**
887 * smack_sb_statfs - Smack check on statfs
888 * @dentry: identifies the file system in question
889 *
890 * Returns 0 if current can read the floor of the filesystem,
891 * and error code otherwise
892 */
smack_sb_statfs(struct dentry * dentry)893 static int smack_sb_statfs(struct dentry *dentry)
894 {
895 struct superblock_smack *sbp = dentry->d_sb->s_security;
896 int rc;
897 struct smk_audit_info ad;
898
899 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
900 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
901
902 rc = smk_curacc(sbp->smk_floor, MAY_READ, &ad);
903 rc = smk_bu_current("statfs", sbp->smk_floor, MAY_READ, rc);
904 return rc;
905 }
906
907 /*
908 * BPRM hooks
909 */
910
911 /**
912 * smack_bprm_set_creds - set creds for exec
913 * @bprm: the exec information
914 *
915 * Returns 0 if it gets a blob, -EPERM if exec forbidden and -ENOMEM otherwise
916 */
smack_bprm_set_creds(struct linux_binprm * bprm)917 static int smack_bprm_set_creds(struct linux_binprm *bprm)
918 {
919 struct inode *inode = file_inode(bprm->file);
920 struct task_smack *bsp = bprm->cred->security;
921 struct inode_smack *isp;
922 struct superblock_smack *sbsp;
923 int rc;
924
925 if (bprm->cred_prepared)
926 return 0;
927
928 isp = inode->i_security;
929 if (isp->smk_task == NULL || isp->smk_task == bsp->smk_task)
930 return 0;
931
932 sbsp = inode->i_sb->s_security;
933 if ((sbsp->smk_flags & SMK_SB_UNTRUSTED) &&
934 isp->smk_task != sbsp->smk_root)
935 return 0;
936
937 if (bprm->unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
938 struct task_struct *tracer;
939 rc = 0;
940
941 rcu_read_lock();
942 tracer = ptrace_parent(current);
943 if (likely(tracer != NULL))
944 rc = smk_ptrace_rule_check(tracer,
945 isp->smk_task,
946 PTRACE_MODE_ATTACH,
947 __func__);
948 rcu_read_unlock();
949
950 if (rc != 0)
951 return rc;
952 } else if (bprm->unsafe)
953 return -EPERM;
954
955 bsp->smk_task = isp->smk_task;
956 bprm->per_clear |= PER_CLEAR_ON_SETID;
957
958 return 0;
959 }
960
961 /**
962 * smack_bprm_committing_creds - Prepare to install the new credentials
963 * from bprm.
964 *
965 * @bprm: binprm for exec
966 */
smack_bprm_committing_creds(struct linux_binprm * bprm)967 static void smack_bprm_committing_creds(struct linux_binprm *bprm)
968 {
969 struct task_smack *bsp = bprm->cred->security;
970
971 if (bsp->smk_task != bsp->smk_forked)
972 current->pdeath_signal = 0;
973 }
974
975 /**
976 * smack_bprm_secureexec - Return the decision to use secureexec.
977 * @bprm: binprm for exec
978 *
979 * Returns 0 on success.
980 */
smack_bprm_secureexec(struct linux_binprm * bprm)981 static int smack_bprm_secureexec(struct linux_binprm *bprm)
982 {
983 struct task_smack *tsp = current_security();
984
985 if (tsp->smk_task != tsp->smk_forked)
986 return 1;
987
988 return 0;
989 }
990
991 /*
992 * Inode hooks
993 */
994
995 /**
996 * smack_inode_alloc_security - allocate an inode blob
997 * @inode: the inode in need of a blob
998 *
999 * Returns 0 if it gets a blob, -ENOMEM otherwise
1000 */
smack_inode_alloc_security(struct inode * inode)1001 static int smack_inode_alloc_security(struct inode *inode)
1002 {
1003 struct smack_known *skp = smk_of_current();
1004
1005 inode->i_security = new_inode_smack(skp);
1006 if (inode->i_security == NULL)
1007 return -ENOMEM;
1008 return 0;
1009 }
1010
1011 /**
1012 * smack_inode_free_security - free an inode blob
1013 * @inode: the inode with a blob
1014 *
1015 * Clears the blob pointer in inode
1016 */
smack_inode_free_security(struct inode * inode)1017 static void smack_inode_free_security(struct inode *inode)
1018 {
1019 kmem_cache_free(smack_inode_cache, inode->i_security);
1020 inode->i_security = NULL;
1021 }
1022
1023 /**
1024 * smack_inode_init_security - copy out the smack from an inode
1025 * @inode: the newly created inode
1026 * @dir: containing directory object
1027 * @qstr: unused
1028 * @name: where to put the attribute name
1029 * @value: where to put the attribute value
1030 * @len: where to put the length of the attribute
1031 *
1032 * Returns 0 if it all works out, -ENOMEM if there's no memory
1033 */
smack_inode_init_security(struct inode * inode,struct inode * dir,const struct qstr * qstr,const char ** name,void ** value,size_t * len)1034 static int smack_inode_init_security(struct inode *inode, struct inode *dir,
1035 const struct qstr *qstr, const char **name,
1036 void **value, size_t *len)
1037 {
1038 struct inode_smack *issp = inode->i_security;
1039 struct smack_known *skp = smk_of_current();
1040 struct smack_known *isp = smk_of_inode(inode);
1041 struct smack_known *dsp = smk_of_inode(dir);
1042 int may;
1043
1044 if (name)
1045 *name = XATTR_SMACK_SUFFIX;
1046
1047 if (value && len) {
1048 rcu_read_lock();
1049 may = smk_access_entry(skp->smk_known, dsp->smk_known,
1050 &skp->smk_rules);
1051 rcu_read_unlock();
1052
1053 /*
1054 * If the access rule allows transmutation and
1055 * the directory requests transmutation then
1056 * by all means transmute.
1057 * Mark the inode as changed.
1058 */
1059 if (may > 0 && ((may & MAY_TRANSMUTE) != 0) &&
1060 smk_inode_transmutable(dir)) {
1061 isp = dsp;
1062 issp->smk_flags |= SMK_INODE_CHANGED;
1063 }
1064
1065 *value = kstrdup(isp->smk_known, GFP_NOFS);
1066 if (*value == NULL)
1067 return -ENOMEM;
1068
1069 *len = strlen(isp->smk_known);
1070 }
1071
1072 return 0;
1073 }
1074
1075 /**
1076 * smack_inode_link - Smack check on link
1077 * @old_dentry: the existing object
1078 * @dir: unused
1079 * @new_dentry: the new object
1080 *
1081 * Returns 0 if access is permitted, an error code otherwise
1082 */
smack_inode_link(struct dentry * old_dentry,struct inode * dir,struct dentry * new_dentry)1083 static int smack_inode_link(struct dentry *old_dentry, struct inode *dir,
1084 struct dentry *new_dentry)
1085 {
1086 struct smack_known *isp;
1087 struct smk_audit_info ad;
1088 int rc;
1089
1090 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1091 smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
1092
1093 isp = smk_of_inode(d_backing_inode(old_dentry));
1094 rc = smk_curacc(isp, MAY_WRITE, &ad);
1095 rc = smk_bu_inode(d_backing_inode(old_dentry), MAY_WRITE, rc);
1096
1097 if (rc == 0 && d_is_positive(new_dentry)) {
1098 isp = smk_of_inode(d_backing_inode(new_dentry));
1099 smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
1100 rc = smk_curacc(isp, MAY_WRITE, &ad);
1101 rc = smk_bu_inode(d_backing_inode(new_dentry), MAY_WRITE, rc);
1102 }
1103
1104 return rc;
1105 }
1106
1107 /**
1108 * smack_inode_unlink - Smack check on inode deletion
1109 * @dir: containing directory object
1110 * @dentry: file to unlink
1111 *
1112 * Returns 0 if current can write the containing directory
1113 * and the object, error code otherwise
1114 */
smack_inode_unlink(struct inode * dir,struct dentry * dentry)1115 static int smack_inode_unlink(struct inode *dir, struct dentry *dentry)
1116 {
1117 struct inode *ip = d_backing_inode(dentry);
1118 struct smk_audit_info ad;
1119 int rc;
1120
1121 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1122 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1123
1124 /*
1125 * You need write access to the thing you're unlinking
1126 */
1127 rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad);
1128 rc = smk_bu_inode(ip, MAY_WRITE, rc);
1129 if (rc == 0) {
1130 /*
1131 * You also need write access to the containing directory
1132 */
1133 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
1134 smk_ad_setfield_u_fs_inode(&ad, dir);
1135 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
1136 rc = smk_bu_inode(dir, MAY_WRITE, rc);
1137 }
1138 return rc;
1139 }
1140
1141 /**
1142 * smack_inode_rmdir - Smack check on directory deletion
1143 * @dir: containing directory object
1144 * @dentry: directory to unlink
1145 *
1146 * Returns 0 if current can write the containing directory
1147 * and the directory, error code otherwise
1148 */
smack_inode_rmdir(struct inode * dir,struct dentry * dentry)1149 static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry)
1150 {
1151 struct smk_audit_info ad;
1152 int rc;
1153
1154 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1155 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1156
1157 /*
1158 * You need write access to the thing you're removing
1159 */
1160 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1161 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1162 if (rc == 0) {
1163 /*
1164 * You also need write access to the containing directory
1165 */
1166 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
1167 smk_ad_setfield_u_fs_inode(&ad, dir);
1168 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
1169 rc = smk_bu_inode(dir, MAY_WRITE, rc);
1170 }
1171
1172 return rc;
1173 }
1174
1175 /**
1176 * smack_inode_rename - Smack check on rename
1177 * @old_inode: unused
1178 * @old_dentry: the old object
1179 * @new_inode: unused
1180 * @new_dentry: the new object
1181 *
1182 * Read and write access is required on both the old and
1183 * new directories.
1184 *
1185 * Returns 0 if access is permitted, an error code otherwise
1186 */
smack_inode_rename(struct inode * old_inode,struct dentry * old_dentry,struct inode * new_inode,struct dentry * new_dentry)1187 static int smack_inode_rename(struct inode *old_inode,
1188 struct dentry *old_dentry,
1189 struct inode *new_inode,
1190 struct dentry *new_dentry)
1191 {
1192 int rc;
1193 struct smack_known *isp;
1194 struct smk_audit_info ad;
1195
1196 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1197 smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
1198
1199 isp = smk_of_inode(d_backing_inode(old_dentry));
1200 rc = smk_curacc(isp, MAY_READWRITE, &ad);
1201 rc = smk_bu_inode(d_backing_inode(old_dentry), MAY_READWRITE, rc);
1202
1203 if (rc == 0 && d_is_positive(new_dentry)) {
1204 isp = smk_of_inode(d_backing_inode(new_dentry));
1205 smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
1206 rc = smk_curacc(isp, MAY_READWRITE, &ad);
1207 rc = smk_bu_inode(d_backing_inode(new_dentry), MAY_READWRITE, rc);
1208 }
1209 return rc;
1210 }
1211
1212 /**
1213 * smack_inode_permission - Smack version of permission()
1214 * @inode: the inode in question
1215 * @mask: the access requested
1216 *
1217 * This is the important Smack hook.
1218 *
1219 * Returns 0 if access is permitted, -EACCES otherwise
1220 */
smack_inode_permission(struct inode * inode,int mask)1221 static int smack_inode_permission(struct inode *inode, int mask)
1222 {
1223 struct superblock_smack *sbsp = inode->i_sb->s_security;
1224 struct smk_audit_info ad;
1225 int no_block = mask & MAY_NOT_BLOCK;
1226 int rc;
1227
1228 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
1229 /*
1230 * No permission to check. Existence test. Yup, it's there.
1231 */
1232 if (mask == 0)
1233 return 0;
1234
1235 if (sbsp->smk_flags & SMK_SB_UNTRUSTED) {
1236 if (smk_of_inode(inode) != sbsp->smk_root)
1237 return -EACCES;
1238 }
1239
1240 /* May be droppable after audit */
1241 if (no_block)
1242 return -ECHILD;
1243 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
1244 smk_ad_setfield_u_fs_inode(&ad, inode);
1245 rc = smk_curacc(smk_of_inode(inode), mask, &ad);
1246 rc = smk_bu_inode(inode, mask, rc);
1247 return rc;
1248 }
1249
1250 /**
1251 * smack_inode_setattr - Smack check for setting attributes
1252 * @dentry: the object
1253 * @iattr: for the force flag
1254 *
1255 * Returns 0 if access is permitted, an error code otherwise
1256 */
smack_inode_setattr(struct dentry * dentry,struct iattr * iattr)1257 static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr)
1258 {
1259 struct smk_audit_info ad;
1260 int rc;
1261
1262 /*
1263 * Need to allow for clearing the setuid bit.
1264 */
1265 if (iattr->ia_valid & ATTR_FORCE)
1266 return 0;
1267 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1268 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1269
1270 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1271 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1272 return rc;
1273 }
1274
1275 /**
1276 * smack_inode_getattr - Smack check for getting attributes
1277 * @mnt: vfsmount of the object
1278 * @dentry: the object
1279 *
1280 * Returns 0 if access is permitted, an error code otherwise
1281 */
smack_inode_getattr(const struct path * path)1282 static int smack_inode_getattr(const struct path *path)
1283 {
1284 struct smk_audit_info ad;
1285 struct inode *inode = d_backing_inode(path->dentry);
1286 int rc;
1287
1288 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1289 smk_ad_setfield_u_fs_path(&ad, *path);
1290 rc = smk_curacc(smk_of_inode(inode), MAY_READ, &ad);
1291 rc = smk_bu_inode(inode, MAY_READ, rc);
1292 return rc;
1293 }
1294
1295 /**
1296 * smack_inode_setxattr - Smack check for setting xattrs
1297 * @dentry: the object
1298 * @name: name of the attribute
1299 * @value: value of the attribute
1300 * @size: size of the value
1301 * @flags: unused
1302 *
1303 * This protects the Smack attribute explicitly.
1304 *
1305 * Returns 0 if access is permitted, an error code otherwise
1306 */
smack_inode_setxattr(struct dentry * dentry,const char * name,const void * value,size_t size,int flags)1307 static int smack_inode_setxattr(struct dentry *dentry, const char *name,
1308 const void *value, size_t size, int flags)
1309 {
1310 struct smk_audit_info ad;
1311 struct smack_known *skp;
1312 int check_priv = 0;
1313 int check_import = 0;
1314 int check_star = 0;
1315 int rc = 0;
1316
1317 /*
1318 * Check label validity here so import won't fail in post_setxattr
1319 */
1320 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
1321 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
1322 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) {
1323 check_priv = 1;
1324 check_import = 1;
1325 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
1326 strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1327 check_priv = 1;
1328 check_import = 1;
1329 check_star = 1;
1330 } else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
1331 check_priv = 1;
1332 if (size != TRANS_TRUE_SIZE ||
1333 strncmp(value, TRANS_TRUE, TRANS_TRUE_SIZE) != 0)
1334 rc = -EINVAL;
1335 } else
1336 rc = cap_inode_setxattr(dentry, name, value, size, flags);
1337
1338 if (check_priv && !smack_privileged(CAP_MAC_ADMIN))
1339 rc = -EPERM;
1340
1341 if (rc == 0 && check_import) {
1342 skp = size ? smk_import_entry(value, size) : NULL;
1343 if (IS_ERR(skp))
1344 rc = PTR_ERR(skp);
1345 else if (skp == NULL || (check_star &&
1346 (skp == &smack_known_star || skp == &smack_known_web)))
1347 rc = -EINVAL;
1348 }
1349
1350 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1351 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1352
1353 if (rc == 0) {
1354 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad);
1355 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc);
1356 }
1357
1358 return rc;
1359 }
1360
1361 /**
1362 * smack_inode_post_setxattr - Apply the Smack update approved above
1363 * @dentry: object
1364 * @name: attribute name
1365 * @value: attribute value
1366 * @size: attribute size
1367 * @flags: unused
1368 *
1369 * Set the pointer in the inode blob to the entry found
1370 * in the master label list.
1371 */
smack_inode_post_setxattr(struct dentry * dentry,const char * name,const void * value,size_t size,int flags)1372 static void smack_inode_post_setxattr(struct dentry *dentry, const char *name,
1373 const void *value, size_t size, int flags)
1374 {
1375 struct smack_known *skp;
1376 struct inode_smack *isp = d_backing_inode(dentry)->i_security;
1377
1378 if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
1379 isp->smk_flags |= SMK_INODE_TRANSMUTE;
1380 return;
1381 }
1382
1383 if (strcmp(name, XATTR_NAME_SMACK) == 0) {
1384 skp = smk_import_entry(value, size);
1385 if (!IS_ERR(skp))
1386 isp->smk_inode = skp;
1387 else
1388 isp->smk_inode = &smack_known_invalid;
1389 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0) {
1390 skp = smk_import_entry(value, size);
1391 if (!IS_ERR(skp))
1392 isp->smk_task = skp;
1393 else
1394 isp->smk_task = &smack_known_invalid;
1395 } else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1396 skp = smk_import_entry(value, size);
1397 if (!IS_ERR(skp))
1398 isp->smk_mmap = skp;
1399 else
1400 isp->smk_mmap = &smack_known_invalid;
1401 }
1402
1403 return;
1404 }
1405
1406 /**
1407 * smack_inode_getxattr - Smack check on getxattr
1408 * @dentry: the object
1409 * @name: unused
1410 *
1411 * Returns 0 if access is permitted, an error code otherwise
1412 */
smack_inode_getxattr(struct dentry * dentry,const char * name)1413 static int smack_inode_getxattr(struct dentry *dentry, const char *name)
1414 {
1415 struct smk_audit_info ad;
1416 int rc;
1417
1418 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
1419 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
1420
1421 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_READ, &ad);
1422 rc = smk_bu_inode(d_backing_inode(dentry), MAY_READ, rc);
1423 return rc;
1424 }
1425
1426 /**
1427 * smack_inode_removexattr - Smack check on removexattr
1428 * @dentry: the object
1429 * @name: name of the attribute
1430 *
1431 * Removing the Smack attribute requires CAP_MAC_ADMIN
1432 *
1433 * Returns 0 if access is permitted, an error code otherwise
1434 */
smack_inode_removexattr(struct dentry * dentry,const char * name)1435 static int smack_inode_removexattr(struct dentry *dentry, const char *name)
1436 {
1437 struct inode_smack *isp;
1438 struct smk_audit_info ad;
1439 int rc = 0;
1440
1441 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
1442 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
1443 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
1444 strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
1445 strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0 ||
1446 strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
1447 if (!smack_privileged(CAP_MAC_ADMIN))
1448 rc = -EPERM;
1449 } else
1450 rc = cap_inode_removexattr(dentry, name);
1451
1452 if (rc != 0)
1453 return 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 if (rc != 0)
1461 return rc;
1462
1463 isp = d_backing_inode(dentry)->i_security;
1464 /*
1465 * Don't do anything special for these.
1466 * XATTR_NAME_SMACKIPIN
1467 * XATTR_NAME_SMACKIPOUT
1468 */
1469 if (strcmp(name, XATTR_NAME_SMACK) == 0) {
1470 struct super_block *sbp = dentry->d_sb;
1471 struct superblock_smack *sbsp = sbp->s_security;
1472
1473 isp->smk_inode = sbsp->smk_default;
1474 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0)
1475 isp->smk_task = NULL;
1476 else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0)
1477 isp->smk_mmap = NULL;
1478 else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0)
1479 isp->smk_flags &= ~SMK_INODE_TRANSMUTE;
1480
1481 return 0;
1482 }
1483
1484 /**
1485 * smack_inode_getsecurity - get smack xattrs
1486 * @inode: the object
1487 * @name: attribute name
1488 * @buffer: where to put the result
1489 * @alloc: duplicate memory
1490 *
1491 * Returns the size of the attribute or an error code
1492 */
smack_inode_getsecurity(struct inode * inode,const char * name,void ** buffer,bool alloc)1493 static int smack_inode_getsecurity(struct inode *inode,
1494 const char *name, void **buffer,
1495 bool alloc)
1496 {
1497 struct socket_smack *ssp;
1498 struct socket *sock;
1499 struct super_block *sbp;
1500 struct inode *ip = (struct inode *)inode;
1501 struct smack_known *isp;
1502
1503 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0)
1504 isp = smk_of_inode(inode);
1505 else {
1506 /*
1507 * The rest of the Smack xattrs are only on sockets.
1508 */
1509 sbp = ip->i_sb;
1510 if (sbp->s_magic != SOCKFS_MAGIC)
1511 return -EOPNOTSUPP;
1512
1513 sock = SOCKET_I(ip);
1514 if (sock == NULL || sock->sk == NULL)
1515 return -EOPNOTSUPP;
1516
1517 ssp = sock->sk->sk_security;
1518
1519 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
1520 isp = ssp->smk_in;
1521 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0)
1522 isp = ssp->smk_out;
1523 else
1524 return -EOPNOTSUPP;
1525 }
1526
1527 if (alloc) {
1528 *buffer = kstrdup(isp->smk_known, GFP_KERNEL);
1529 if (*buffer == NULL)
1530 return -ENOMEM;
1531 }
1532
1533 return strlen(isp->smk_known);
1534 }
1535
1536
1537 /**
1538 * smack_inode_listsecurity - list the Smack attributes
1539 * @inode: the object
1540 * @buffer: where they go
1541 * @buffer_size: size of buffer
1542 */
smack_inode_listsecurity(struct inode * inode,char * buffer,size_t buffer_size)1543 static int smack_inode_listsecurity(struct inode *inode, char *buffer,
1544 size_t buffer_size)
1545 {
1546 int len = sizeof(XATTR_NAME_SMACK);
1547
1548 if (buffer != NULL && len <= buffer_size)
1549 memcpy(buffer, XATTR_NAME_SMACK, len);
1550
1551 return len;
1552 }
1553
1554 /**
1555 * smack_inode_getsecid - Extract inode's security id
1556 * @inode: inode to extract the info from
1557 * @secid: where result will be saved
1558 */
smack_inode_getsecid(struct inode * inode,u32 * secid)1559 static void smack_inode_getsecid(struct inode *inode, u32 *secid)
1560 {
1561 struct inode_smack *isp = inode->i_security;
1562
1563 *secid = isp->smk_inode->smk_secid;
1564 }
1565
1566 /*
1567 * File Hooks
1568 */
1569
1570 /*
1571 * There is no smack_file_permission hook
1572 *
1573 * Should access checks be done on each read or write?
1574 * UNICOS and SELinux say yes.
1575 * Trusted Solaris, Trusted Irix, and just about everyone else says no.
1576 *
1577 * I'll say no for now. Smack does not do the frequent
1578 * label changing that SELinux does.
1579 */
1580
1581 /**
1582 * smack_file_alloc_security - assign a file security blob
1583 * @file: the object
1584 *
1585 * The security blob for a file is a pointer to the master
1586 * label list, so no allocation is done.
1587 *
1588 * f_security is the owner security information. It
1589 * isn't used on file access checks, it's for send_sigio.
1590 *
1591 * Returns 0
1592 */
smack_file_alloc_security(struct file * file)1593 static int smack_file_alloc_security(struct file *file)
1594 {
1595 struct smack_known *skp = smk_of_current();
1596
1597 file->f_security = skp;
1598 return 0;
1599 }
1600
1601 /**
1602 * smack_file_free_security - clear a file security blob
1603 * @file: the object
1604 *
1605 * The security blob for a file is a pointer to the master
1606 * label list, so no memory is freed.
1607 */
smack_file_free_security(struct file * file)1608 static void smack_file_free_security(struct file *file)
1609 {
1610 file->f_security = NULL;
1611 }
1612
1613 /**
1614 * smack_file_ioctl - Smack check on ioctls
1615 * @file: the object
1616 * @cmd: what to do
1617 * @arg: unused
1618 *
1619 * Relies heavily on the correct use of the ioctl command conventions.
1620 *
1621 * Returns 0 if allowed, error code otherwise
1622 */
smack_file_ioctl(struct file * file,unsigned int cmd,unsigned long arg)1623 static int smack_file_ioctl(struct file *file, unsigned int cmd,
1624 unsigned long arg)
1625 {
1626 int rc = 0;
1627 struct smk_audit_info ad;
1628 struct inode *inode = file_inode(file);
1629
1630 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1631 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1632
1633 if (_IOC_DIR(cmd) & _IOC_WRITE) {
1634 rc = smk_curacc(smk_of_inode(inode), MAY_WRITE, &ad);
1635 rc = smk_bu_file(file, MAY_WRITE, rc);
1636 }
1637
1638 if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ)) {
1639 rc = smk_curacc(smk_of_inode(inode), MAY_READ, &ad);
1640 rc = smk_bu_file(file, MAY_READ, rc);
1641 }
1642
1643 return rc;
1644 }
1645
1646 /**
1647 * smack_file_lock - Smack check on file locking
1648 * @file: the object
1649 * @cmd: unused
1650 *
1651 * Returns 0 if current has lock access, error code otherwise
1652 */
smack_file_lock(struct file * file,unsigned int cmd)1653 static int smack_file_lock(struct file *file, unsigned int cmd)
1654 {
1655 struct smk_audit_info ad;
1656 int rc;
1657 struct inode *inode = file_inode(file);
1658
1659 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1660 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1661 rc = smk_curacc(smk_of_inode(inode), MAY_LOCK, &ad);
1662 rc = smk_bu_file(file, MAY_LOCK, rc);
1663 return rc;
1664 }
1665
1666 /**
1667 * smack_file_fcntl - Smack check on fcntl
1668 * @file: the object
1669 * @cmd: what action to check
1670 * @arg: unused
1671 *
1672 * Generally these operations are harmless.
1673 * File locking operations present an obvious mechanism
1674 * for passing information, so they require write access.
1675 *
1676 * Returns 0 if current has access, error code otherwise
1677 */
smack_file_fcntl(struct file * file,unsigned int cmd,unsigned long arg)1678 static int smack_file_fcntl(struct file *file, unsigned int cmd,
1679 unsigned long arg)
1680 {
1681 struct smk_audit_info ad;
1682 int rc = 0;
1683 struct inode *inode = file_inode(file);
1684
1685 switch (cmd) {
1686 case F_GETLK:
1687 break;
1688 case F_SETLK:
1689 case F_SETLKW:
1690 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1691 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1692 rc = smk_curacc(smk_of_inode(inode), MAY_LOCK, &ad);
1693 rc = smk_bu_file(file, MAY_LOCK, rc);
1694 break;
1695 case F_SETOWN:
1696 case F_SETSIG:
1697 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1698 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1699 rc = smk_curacc(smk_of_inode(inode), MAY_WRITE, &ad);
1700 rc = smk_bu_file(file, MAY_WRITE, rc);
1701 break;
1702 default:
1703 break;
1704 }
1705
1706 return rc;
1707 }
1708
1709 /**
1710 * smack_mmap_file :
1711 * Check permissions for a mmap operation. The @file may be NULL, e.g.
1712 * if mapping anonymous memory.
1713 * @file contains the file structure for file to map (may be NULL).
1714 * @reqprot contains the protection requested by the application.
1715 * @prot contains the protection that will be applied by the kernel.
1716 * @flags contains the operational flags.
1717 * Return 0 if permission is granted.
1718 */
smack_mmap_file(struct file * file,unsigned long reqprot,unsigned long prot,unsigned long flags)1719 static int smack_mmap_file(struct file *file,
1720 unsigned long reqprot, unsigned long prot,
1721 unsigned long flags)
1722 {
1723 struct smack_known *skp;
1724 struct smack_known *mkp;
1725 struct smack_rule *srp;
1726 struct task_smack *tsp;
1727 struct smack_known *okp;
1728 struct inode_smack *isp;
1729 struct superblock_smack *sbsp;
1730 int may;
1731 int mmay;
1732 int tmay;
1733 int rc;
1734
1735 if (file == NULL)
1736 return 0;
1737
1738 isp = file_inode(file)->i_security;
1739 if (isp->smk_mmap == NULL)
1740 return 0;
1741 sbsp = file_inode(file)->i_sb->s_security;
1742 if (sbsp->smk_flags & SMK_SB_UNTRUSTED &&
1743 isp->smk_mmap != sbsp->smk_root)
1744 return -EACCES;
1745 mkp = isp->smk_mmap;
1746
1747 tsp = current_security();
1748 skp = smk_of_current();
1749 rc = 0;
1750
1751 rcu_read_lock();
1752 /*
1753 * For each Smack rule associated with the subject
1754 * label verify that the SMACK64MMAP also has access
1755 * to that rule's object label.
1756 */
1757 list_for_each_entry_rcu(srp, &skp->smk_rules, list) {
1758 okp = srp->smk_object;
1759 /*
1760 * Matching labels always allows access.
1761 */
1762 if (mkp->smk_known == okp->smk_known)
1763 continue;
1764 /*
1765 * If there is a matching local rule take
1766 * that into account as well.
1767 */
1768 may = smk_access_entry(srp->smk_subject->smk_known,
1769 okp->smk_known,
1770 &tsp->smk_rules);
1771 if (may == -ENOENT)
1772 may = srp->smk_access;
1773 else
1774 may &= srp->smk_access;
1775 /*
1776 * If may is zero the SMACK64MMAP subject can't
1777 * possibly have less access.
1778 */
1779 if (may == 0)
1780 continue;
1781
1782 /*
1783 * Fetch the global list entry.
1784 * If there isn't one a SMACK64MMAP subject
1785 * can't have as much access as current.
1786 */
1787 mmay = smk_access_entry(mkp->smk_known, okp->smk_known,
1788 &mkp->smk_rules);
1789 if (mmay == -ENOENT) {
1790 rc = -EACCES;
1791 break;
1792 }
1793 /*
1794 * If there is a local entry it modifies the
1795 * potential access, too.
1796 */
1797 tmay = smk_access_entry(mkp->smk_known, okp->smk_known,
1798 &tsp->smk_rules);
1799 if (tmay != -ENOENT)
1800 mmay &= tmay;
1801
1802 /*
1803 * If there is any access available to current that is
1804 * not available to a SMACK64MMAP subject
1805 * deny access.
1806 */
1807 if ((may | mmay) != mmay) {
1808 rc = -EACCES;
1809 break;
1810 }
1811 }
1812
1813 rcu_read_unlock();
1814
1815 return rc;
1816 }
1817
1818 /**
1819 * smack_file_set_fowner - set the file security blob value
1820 * @file: object in question
1821 *
1822 */
smack_file_set_fowner(struct file * file)1823 static void smack_file_set_fowner(struct file *file)
1824 {
1825 file->f_security = smk_of_current();
1826 }
1827
1828 /**
1829 * smack_file_send_sigiotask - Smack on sigio
1830 * @tsk: The target task
1831 * @fown: the object the signal come from
1832 * @signum: unused
1833 *
1834 * Allow a privileged task to get signals even if it shouldn't
1835 *
1836 * Returns 0 if a subject with the object's smack could
1837 * write to the task, an error code otherwise.
1838 */
smack_file_send_sigiotask(struct task_struct * tsk,struct fown_struct * fown,int signum)1839 static int smack_file_send_sigiotask(struct task_struct *tsk,
1840 struct fown_struct *fown, int signum)
1841 {
1842 struct smack_known *skp;
1843 struct smack_known *tkp = smk_of_task(tsk->cred->security);
1844 struct file *file;
1845 int rc;
1846 struct smk_audit_info ad;
1847
1848 /*
1849 * struct fown_struct is never outside the context of a struct file
1850 */
1851 file = container_of(fown, struct file, f_owner);
1852
1853 /* we don't log here as rc can be overriden */
1854 skp = file->f_security;
1855 rc = smk_access(skp, tkp, MAY_DELIVER, NULL);
1856 rc = smk_bu_note("sigiotask", skp, tkp, MAY_DELIVER, rc);
1857 if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE))
1858 rc = 0;
1859
1860 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1861 smk_ad_setfield_u_tsk(&ad, tsk);
1862 smack_log(skp->smk_known, tkp->smk_known, MAY_DELIVER, rc, &ad);
1863 return rc;
1864 }
1865
1866 /**
1867 * smack_file_receive - Smack file receive check
1868 * @file: the object
1869 *
1870 * Returns 0 if current has access, error code otherwise
1871 */
smack_file_receive(struct file * file)1872 static int smack_file_receive(struct file *file)
1873 {
1874 int rc;
1875 int may = 0;
1876 struct smk_audit_info ad;
1877 struct inode *inode = file_inode(file);
1878 struct socket *sock;
1879 struct task_smack *tsp;
1880 struct socket_smack *ssp;
1881
1882 if (unlikely(IS_PRIVATE(inode)))
1883 return 0;
1884
1885 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1886 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1887
1888 if (S_ISSOCK(inode->i_mode)) {
1889 sock = SOCKET_I(inode);
1890 ssp = sock->sk->sk_security;
1891 tsp = current_security();
1892 /*
1893 * If the receiving process can't write to the
1894 * passed socket or if the passed socket can't
1895 * write to the receiving process don't accept
1896 * the passed socket.
1897 */
1898 rc = smk_access(tsp->smk_task, ssp->smk_out, MAY_WRITE, &ad);
1899 rc = smk_bu_file(file, may, rc);
1900 if (rc < 0)
1901 return rc;
1902 rc = smk_access(ssp->smk_in, tsp->smk_task, MAY_WRITE, &ad);
1903 rc = smk_bu_file(file, may, rc);
1904 return rc;
1905 }
1906 /*
1907 * This code relies on bitmasks.
1908 */
1909 if (file->f_mode & FMODE_READ)
1910 may = MAY_READ;
1911 if (file->f_mode & FMODE_WRITE)
1912 may |= MAY_WRITE;
1913
1914 rc = smk_curacc(smk_of_inode(inode), may, &ad);
1915 rc = smk_bu_file(file, may, rc);
1916 return rc;
1917 }
1918
1919 /**
1920 * smack_file_open - Smack dentry open processing
1921 * @file: the object
1922 * @cred: task credential
1923 *
1924 * Set the security blob in the file structure.
1925 * Allow the open only if the task has read access. There are
1926 * many read operations (e.g. fstat) that you can do with an
1927 * fd even if you have the file open write-only.
1928 *
1929 * Returns 0
1930 */
smack_file_open(struct file * file,const struct cred * cred)1931 static int smack_file_open(struct file *file, const struct cred *cred)
1932 {
1933 struct task_smack *tsp = cred->security;
1934 struct inode *inode = file_inode(file);
1935 struct smk_audit_info ad;
1936 int rc;
1937
1938 if (smack_privileged(CAP_MAC_OVERRIDE))
1939 return 0;
1940
1941 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1942 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1943 rc = smk_access(tsp->smk_task, smk_of_inode(inode), MAY_READ, &ad);
1944 rc = smk_bu_credfile(cred, file, MAY_READ, rc);
1945
1946 return rc;
1947 }
1948
1949 /*
1950 * Task hooks
1951 */
1952
1953 /**
1954 * smack_cred_alloc_blank - "allocate" blank task-level security credentials
1955 * @new: the new credentials
1956 * @gfp: the atomicity of any memory allocations
1957 *
1958 * Prepare a blank set of credentials for modification. This must allocate all
1959 * the memory the LSM module might require such that cred_transfer() can
1960 * complete without error.
1961 */
smack_cred_alloc_blank(struct cred * cred,gfp_t gfp)1962 static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp)
1963 {
1964 struct task_smack *tsp;
1965
1966 tsp = new_task_smack(NULL, NULL, gfp);
1967 if (tsp == NULL)
1968 return -ENOMEM;
1969
1970 cred->security = tsp;
1971
1972 return 0;
1973 }
1974
1975
1976 /**
1977 * smack_cred_free - "free" task-level security credentials
1978 * @cred: the credentials in question
1979 *
1980 */
smack_cred_free(struct cred * cred)1981 static void smack_cred_free(struct cred *cred)
1982 {
1983 struct task_smack *tsp = cred->security;
1984 struct smack_rule *rp;
1985 struct list_head *l;
1986 struct list_head *n;
1987
1988 if (tsp == NULL)
1989 return;
1990 cred->security = NULL;
1991
1992 smk_destroy_label_list(&tsp->smk_relabel);
1993
1994 list_for_each_safe(l, n, &tsp->smk_rules) {
1995 rp = list_entry(l, struct smack_rule, list);
1996 list_del(&rp->list);
1997 kfree(rp);
1998 }
1999 kfree(tsp);
2000 }
2001
2002 /**
2003 * smack_cred_prepare - prepare new set of credentials for modification
2004 * @new: the new credentials
2005 * @old: the original credentials
2006 * @gfp: the atomicity of any memory allocations
2007 *
2008 * Prepare a new set of credentials for modification.
2009 */
smack_cred_prepare(struct cred * new,const struct cred * old,gfp_t gfp)2010 static int smack_cred_prepare(struct cred *new, const struct cred *old,
2011 gfp_t gfp)
2012 {
2013 struct task_smack *old_tsp = old->security;
2014 struct task_smack *new_tsp;
2015 int rc;
2016
2017 new_tsp = new_task_smack(old_tsp->smk_task, old_tsp->smk_task, gfp);
2018 if (new_tsp == NULL)
2019 return -ENOMEM;
2020
2021 rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp);
2022 if (rc != 0)
2023 return rc;
2024
2025 rc = smk_copy_relabel(&new_tsp->smk_relabel, &old_tsp->smk_relabel,
2026 gfp);
2027 if (rc != 0)
2028 return rc;
2029
2030 new->security = new_tsp;
2031 return 0;
2032 }
2033
2034 /**
2035 * smack_cred_transfer - Transfer the old credentials to the new credentials
2036 * @new: the new credentials
2037 * @old: the original credentials
2038 *
2039 * Fill in a set of blank credentials from another set of credentials.
2040 */
smack_cred_transfer(struct cred * new,const struct cred * old)2041 static void smack_cred_transfer(struct cred *new, const struct cred *old)
2042 {
2043 struct task_smack *old_tsp = old->security;
2044 struct task_smack *new_tsp = new->security;
2045
2046 new_tsp->smk_task = old_tsp->smk_task;
2047 new_tsp->smk_forked = old_tsp->smk_task;
2048 mutex_init(&new_tsp->smk_rules_lock);
2049 INIT_LIST_HEAD(&new_tsp->smk_rules);
2050
2051
2052 /* cbs copy rule list */
2053 }
2054
2055 /**
2056 * smack_kernel_act_as - Set the subjective context in a set of credentials
2057 * @new: points to the set of credentials to be modified.
2058 * @secid: specifies the security ID to be set
2059 *
2060 * Set the security data for a kernel service.
2061 */
smack_kernel_act_as(struct cred * new,u32 secid)2062 static int smack_kernel_act_as(struct cred *new, u32 secid)
2063 {
2064 struct task_smack *new_tsp = new->security;
2065 struct smack_known *skp = smack_from_secid(secid);
2066
2067 if (skp == NULL)
2068 return -EINVAL;
2069
2070 new_tsp->smk_task = skp;
2071 return 0;
2072 }
2073
2074 /**
2075 * smack_kernel_create_files_as - Set the file creation label in a set of creds
2076 * @new: points to the set of credentials to be modified
2077 * @inode: points to the inode to use as a reference
2078 *
2079 * Set the file creation context in a set of credentials to the same
2080 * as the objective context of the specified inode
2081 */
smack_kernel_create_files_as(struct cred * new,struct inode * inode)2082 static int smack_kernel_create_files_as(struct cred *new,
2083 struct inode *inode)
2084 {
2085 struct inode_smack *isp = inode->i_security;
2086 struct task_smack *tsp = new->security;
2087
2088 tsp->smk_forked = isp->smk_inode;
2089 tsp->smk_task = tsp->smk_forked;
2090 return 0;
2091 }
2092
2093 /**
2094 * smk_curacc_on_task - helper to log task related access
2095 * @p: the task object
2096 * @access: the access requested
2097 * @caller: name of the calling function for audit
2098 *
2099 * Return 0 if access is permitted
2100 */
smk_curacc_on_task(struct task_struct * p,int access,const char * caller)2101 static int smk_curacc_on_task(struct task_struct *p, int access,
2102 const char *caller)
2103 {
2104 struct smk_audit_info ad;
2105 struct smack_known *skp = smk_of_task_struct(p);
2106 int rc;
2107
2108 smk_ad_init(&ad, caller, LSM_AUDIT_DATA_TASK);
2109 smk_ad_setfield_u_tsk(&ad, p);
2110 rc = smk_curacc(skp, access, &ad);
2111 rc = smk_bu_task(p, access, rc);
2112 return rc;
2113 }
2114
2115 /**
2116 * smack_task_setpgid - Smack check on setting pgid
2117 * @p: the task object
2118 * @pgid: unused
2119 *
2120 * Return 0 if write access is permitted
2121 */
smack_task_setpgid(struct task_struct * p,pid_t pgid)2122 static int smack_task_setpgid(struct task_struct *p, pid_t pgid)
2123 {
2124 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2125 }
2126
2127 /**
2128 * smack_task_getpgid - Smack access check for getpgid
2129 * @p: the object task
2130 *
2131 * Returns 0 if current can read the object task, error code otherwise
2132 */
smack_task_getpgid(struct task_struct * p)2133 static int smack_task_getpgid(struct task_struct *p)
2134 {
2135 return smk_curacc_on_task(p, MAY_READ, __func__);
2136 }
2137
2138 /**
2139 * smack_task_getsid - Smack access check for getsid
2140 * @p: the object task
2141 *
2142 * Returns 0 if current can read the object task, error code otherwise
2143 */
smack_task_getsid(struct task_struct * p)2144 static int smack_task_getsid(struct task_struct *p)
2145 {
2146 return smk_curacc_on_task(p, MAY_READ, __func__);
2147 }
2148
2149 /**
2150 * smack_task_getsecid - get the secid of the task
2151 * @p: the object task
2152 * @secid: where to put the result
2153 *
2154 * Sets the secid to contain a u32 version of the smack label.
2155 */
smack_task_getsecid(struct task_struct * p,u32 * secid)2156 static void smack_task_getsecid(struct task_struct *p, u32 *secid)
2157 {
2158 struct smack_known *skp = smk_of_task_struct(p);
2159
2160 *secid = skp->smk_secid;
2161 }
2162
2163 /**
2164 * smack_task_setnice - Smack check on setting nice
2165 * @p: the task object
2166 * @nice: unused
2167 *
2168 * Return 0 if write access is permitted
2169 */
smack_task_setnice(struct task_struct * p,int nice)2170 static int smack_task_setnice(struct task_struct *p, int nice)
2171 {
2172 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2173 }
2174
2175 /**
2176 * smack_task_setioprio - Smack check on setting ioprio
2177 * @p: the task object
2178 * @ioprio: unused
2179 *
2180 * Return 0 if write access is permitted
2181 */
smack_task_setioprio(struct task_struct * p,int ioprio)2182 static int smack_task_setioprio(struct task_struct *p, int ioprio)
2183 {
2184 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2185 }
2186
2187 /**
2188 * smack_task_getioprio - Smack check on reading ioprio
2189 * @p: the task object
2190 *
2191 * Return 0 if read access is permitted
2192 */
smack_task_getioprio(struct task_struct * p)2193 static int smack_task_getioprio(struct task_struct *p)
2194 {
2195 return smk_curacc_on_task(p, MAY_READ, __func__);
2196 }
2197
2198 /**
2199 * smack_task_setscheduler - Smack check on setting scheduler
2200 * @p: the task object
2201 * @policy: unused
2202 * @lp: unused
2203 *
2204 * Return 0 if read access is permitted
2205 */
smack_task_setscheduler(struct task_struct * p)2206 static int smack_task_setscheduler(struct task_struct *p)
2207 {
2208 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2209 }
2210
2211 /**
2212 * smack_task_getscheduler - Smack check on reading scheduler
2213 * @p: the task object
2214 *
2215 * Return 0 if read access is permitted
2216 */
smack_task_getscheduler(struct task_struct * p)2217 static int smack_task_getscheduler(struct task_struct *p)
2218 {
2219 return smk_curacc_on_task(p, MAY_READ, __func__);
2220 }
2221
2222 /**
2223 * smack_task_movememory - Smack check on moving memory
2224 * @p: the task object
2225 *
2226 * Return 0 if write access is permitted
2227 */
smack_task_movememory(struct task_struct * p)2228 static int smack_task_movememory(struct task_struct *p)
2229 {
2230 return smk_curacc_on_task(p, MAY_WRITE, __func__);
2231 }
2232
2233 /**
2234 * smack_task_kill - Smack check on signal delivery
2235 * @p: the task object
2236 * @info: unused
2237 * @sig: unused
2238 * @secid: identifies the smack to use in lieu of current's
2239 *
2240 * Return 0 if write access is permitted
2241 *
2242 * The secid behavior is an artifact of an SELinux hack
2243 * in the USB code. Someday it may go away.
2244 */
smack_task_kill(struct task_struct * p,struct siginfo * info,int sig,u32 secid)2245 static int smack_task_kill(struct task_struct *p, struct siginfo *info,
2246 int sig, u32 secid)
2247 {
2248 struct smk_audit_info ad;
2249 struct smack_known *skp;
2250 struct smack_known *tkp = smk_of_task_struct(p);
2251 int rc;
2252
2253 if (!sig)
2254 return 0; /* null signal; existence test */
2255
2256 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
2257 smk_ad_setfield_u_tsk(&ad, p);
2258 /*
2259 * Sending a signal requires that the sender
2260 * can write the receiver.
2261 */
2262 if (secid == 0) {
2263 rc = smk_curacc(tkp, MAY_DELIVER, &ad);
2264 rc = smk_bu_task(p, MAY_DELIVER, rc);
2265 return rc;
2266 }
2267 /*
2268 * If the secid isn't 0 we're dealing with some USB IO
2269 * specific behavior. This is not clean. For one thing
2270 * we can't take privilege into account.
2271 */
2272 skp = smack_from_secid(secid);
2273 rc = smk_access(skp, tkp, MAY_DELIVER, &ad);
2274 rc = smk_bu_note("USB signal", skp, tkp, MAY_DELIVER, rc);
2275 return rc;
2276 }
2277
2278 /**
2279 * smack_task_wait - Smack access check for waiting
2280 * @p: task to wait for
2281 *
2282 * Returns 0
2283 */
smack_task_wait(struct task_struct * p)2284 static int smack_task_wait(struct task_struct *p)
2285 {
2286 /*
2287 * Allow the operation to succeed.
2288 * Zombies are bad.
2289 * In userless environments (e.g. phones) programs
2290 * get marked with SMACK64EXEC and even if the parent
2291 * and child shouldn't be talking the parent still
2292 * may expect to know when the child exits.
2293 */
2294 return 0;
2295 }
2296
2297 /**
2298 * smack_task_to_inode - copy task smack into the inode blob
2299 * @p: task to copy from
2300 * @inode: inode to copy to
2301 *
2302 * Sets the smack pointer in the inode security blob
2303 */
smack_task_to_inode(struct task_struct * p,struct inode * inode)2304 static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
2305 {
2306 struct inode_smack *isp = inode->i_security;
2307 struct smack_known *skp = smk_of_task_struct(p);
2308
2309 isp->smk_inode = skp;
2310 }
2311
2312 /*
2313 * Socket hooks.
2314 */
2315
2316 /**
2317 * smack_sk_alloc_security - Allocate a socket blob
2318 * @sk: the socket
2319 * @family: unused
2320 * @gfp_flags: memory allocation flags
2321 *
2322 * Assign Smack pointers to current
2323 *
2324 * Returns 0 on success, -ENOMEM is there's no memory
2325 */
smack_sk_alloc_security(struct sock * sk,int family,gfp_t gfp_flags)2326 static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags)
2327 {
2328 struct smack_known *skp = smk_of_current();
2329 struct socket_smack *ssp;
2330
2331 ssp = kzalloc(sizeof(struct socket_smack), gfp_flags);
2332 if (ssp == NULL)
2333 return -ENOMEM;
2334
2335 ssp->smk_in = skp;
2336 ssp->smk_out = skp;
2337 ssp->smk_packet = NULL;
2338
2339 sk->sk_security = ssp;
2340
2341 return 0;
2342 }
2343
2344 /**
2345 * smack_sk_free_security - Free a socket blob
2346 * @sk: the socket
2347 *
2348 * Clears the blob pointer
2349 */
smack_sk_free_security(struct sock * sk)2350 static void smack_sk_free_security(struct sock *sk)
2351 {
2352 kfree(sk->sk_security);
2353 }
2354
2355 /**
2356 * smack_ipv4host_label - check host based restrictions
2357 * @sip: the object end
2358 *
2359 * looks for host based access restrictions
2360 *
2361 * This version will only be appropriate for really small sets of single label
2362 * hosts. The caller is responsible for ensuring that the RCU read lock is
2363 * taken before calling this function.
2364 *
2365 * Returns the label of the far end or NULL if it's not special.
2366 */
smack_ipv4host_label(struct sockaddr_in * sip)2367 static struct smack_known *smack_ipv4host_label(struct sockaddr_in *sip)
2368 {
2369 struct smk_net4addr *snp;
2370 struct in_addr *siap = &sip->sin_addr;
2371
2372 if (siap->s_addr == 0)
2373 return NULL;
2374
2375 list_for_each_entry_rcu(snp, &smk_net4addr_list, list)
2376 /*
2377 * we break after finding the first match because
2378 * the list is sorted from longest to shortest mask
2379 * so we have found the most specific match
2380 */
2381 if (snp->smk_host.s_addr ==
2382 (siap->s_addr & snp->smk_mask.s_addr))
2383 return snp->smk_label;
2384
2385 return NULL;
2386 }
2387
2388 #if IS_ENABLED(CONFIG_IPV6)
2389 /*
2390 * smk_ipv6_localhost - Check for local ipv6 host address
2391 * @sip: the address
2392 *
2393 * Returns boolean true if this is the localhost address
2394 */
smk_ipv6_localhost(struct sockaddr_in6 * sip)2395 static bool smk_ipv6_localhost(struct sockaddr_in6 *sip)
2396 {
2397 __be16 *be16p = (__be16 *)&sip->sin6_addr;
2398 __be32 *be32p = (__be32 *)&sip->sin6_addr;
2399
2400 if (be32p[0] == 0 && be32p[1] == 0 && be32p[2] == 0 && be16p[6] == 0 &&
2401 ntohs(be16p[7]) == 1)
2402 return true;
2403 return false;
2404 }
2405
2406 /**
2407 * smack_ipv6host_label - check host based restrictions
2408 * @sip: the object end
2409 *
2410 * looks for host based access restrictions
2411 *
2412 * This version will only be appropriate for really small sets of single label
2413 * hosts. The caller is responsible for ensuring that the RCU read lock is
2414 * taken before calling this function.
2415 *
2416 * Returns the label of the far end or NULL if it's not special.
2417 */
smack_ipv6host_label(struct sockaddr_in6 * sip)2418 static struct smack_known *smack_ipv6host_label(struct sockaddr_in6 *sip)
2419 {
2420 struct smk_net6addr *snp;
2421 struct in6_addr *sap = &sip->sin6_addr;
2422 int i;
2423 int found = 0;
2424
2425 /*
2426 * It's local. Don't look for a host label.
2427 */
2428 if (smk_ipv6_localhost(sip))
2429 return NULL;
2430
2431 list_for_each_entry_rcu(snp, &smk_net6addr_list, list) {
2432 /*
2433 * we break after finding the first match because
2434 * the list is sorted from longest to shortest mask
2435 * so we have found the most specific match
2436 */
2437 for (found = 1, i = 0; i < 8; i++) {
2438 /*
2439 * If the label is NULL the entry has
2440 * been renounced. Ignore it.
2441 */
2442 if (snp->smk_label == NULL)
2443 continue;
2444 if ((sap->s6_addr16[i] & snp->smk_mask.s6_addr16[i]) !=
2445 snp->smk_host.s6_addr16[i]) {
2446 found = 0;
2447 break;
2448 }
2449 }
2450 if (found)
2451 return snp->smk_label;
2452 }
2453
2454 return NULL;
2455 }
2456 #endif /* CONFIG_IPV6 */
2457
2458 /**
2459 * smack_netlabel - Set the secattr on a socket
2460 * @sk: the socket
2461 * @labeled: socket label scheme
2462 *
2463 * Convert the outbound smack value (smk_out) to a
2464 * secattr and attach it to the socket.
2465 *
2466 * Returns 0 on success or an error code
2467 */
smack_netlabel(struct sock * sk,int labeled)2468 static int smack_netlabel(struct sock *sk, int labeled)
2469 {
2470 struct smack_known *skp;
2471 struct socket_smack *ssp = sk->sk_security;
2472 int rc = 0;
2473
2474 /*
2475 * Usually the netlabel code will handle changing the
2476 * packet labeling based on the label.
2477 * The case of a single label host is different, because
2478 * a single label host should never get a labeled packet
2479 * even though the label is usually associated with a packet
2480 * label.
2481 */
2482 local_bh_disable();
2483 bh_lock_sock_nested(sk);
2484
2485 if (ssp->smk_out == smack_net_ambient ||
2486 labeled == SMACK_UNLABELED_SOCKET)
2487 netlbl_sock_delattr(sk);
2488 else {
2489 skp = ssp->smk_out;
2490 rc = netlbl_sock_setattr(sk, sk->sk_family, &skp->smk_netlabel);
2491 }
2492
2493 bh_unlock_sock(sk);
2494 local_bh_enable();
2495
2496 return rc;
2497 }
2498
2499 /**
2500 * smack_netlbel_send - Set the secattr on a socket and perform access checks
2501 * @sk: the socket
2502 * @sap: the destination address
2503 *
2504 * Set the correct secattr for the given socket based on the destination
2505 * address and perform any outbound access checks needed.
2506 *
2507 * Returns 0 on success or an error code.
2508 *
2509 */
smack_netlabel_send(struct sock * sk,struct sockaddr_in * sap)2510 static int smack_netlabel_send(struct sock *sk, struct sockaddr_in *sap)
2511 {
2512 struct smack_known *skp;
2513 int rc;
2514 int sk_lbl;
2515 struct smack_known *hkp;
2516 struct socket_smack *ssp = sk->sk_security;
2517 struct smk_audit_info ad;
2518
2519 rcu_read_lock();
2520 hkp = smack_ipv4host_label(sap);
2521 if (hkp != NULL) {
2522 #ifdef CONFIG_AUDIT
2523 struct lsm_network_audit net;
2524
2525 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
2526 ad.a.u.net->family = sap->sin_family;
2527 ad.a.u.net->dport = sap->sin_port;
2528 ad.a.u.net->v4info.daddr = sap->sin_addr.s_addr;
2529 #endif
2530 sk_lbl = SMACK_UNLABELED_SOCKET;
2531 skp = ssp->smk_out;
2532 rc = smk_access(skp, hkp, MAY_WRITE, &ad);
2533 rc = smk_bu_note("IPv4 host check", skp, hkp, MAY_WRITE, rc);
2534 } else {
2535 sk_lbl = SMACK_CIPSO_SOCKET;
2536 rc = 0;
2537 }
2538 rcu_read_unlock();
2539 if (rc != 0)
2540 return rc;
2541
2542 return smack_netlabel(sk, sk_lbl);
2543 }
2544
2545 #if IS_ENABLED(CONFIG_IPV6)
2546 /**
2547 * smk_ipv6_check - check Smack access
2548 * @subject: subject Smack label
2549 * @object: object Smack label
2550 * @address: address
2551 * @act: the action being taken
2552 *
2553 * Check an IPv6 access
2554 */
smk_ipv6_check(struct smack_known * subject,struct smack_known * object,struct sockaddr_in6 * address,int act)2555 static int smk_ipv6_check(struct smack_known *subject,
2556 struct smack_known *object,
2557 struct sockaddr_in6 *address, int act)
2558 {
2559 #ifdef CONFIG_AUDIT
2560 struct lsm_network_audit net;
2561 #endif
2562 struct smk_audit_info ad;
2563 int rc;
2564
2565 #ifdef CONFIG_AUDIT
2566 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
2567 ad.a.u.net->family = PF_INET6;
2568 ad.a.u.net->dport = ntohs(address->sin6_port);
2569 if (act == SMK_RECEIVING)
2570 ad.a.u.net->v6info.saddr = address->sin6_addr;
2571 else
2572 ad.a.u.net->v6info.daddr = address->sin6_addr;
2573 #endif
2574 rc = smk_access(subject, object, MAY_WRITE, &ad);
2575 rc = smk_bu_note("IPv6 check", subject, object, MAY_WRITE, rc);
2576 return rc;
2577 }
2578 #endif /* CONFIG_IPV6 */
2579
2580 #ifdef SMACK_IPV6_PORT_LABELING
2581 /**
2582 * smk_ipv6_port_label - Smack port access table management
2583 * @sock: socket
2584 * @address: address
2585 *
2586 * Create or update the port list entry
2587 */
smk_ipv6_port_label(struct socket * sock,struct sockaddr * address)2588 static void smk_ipv6_port_label(struct socket *sock, struct sockaddr *address)
2589 {
2590 struct sock *sk = sock->sk;
2591 struct sockaddr_in6 *addr6;
2592 struct socket_smack *ssp = sock->sk->sk_security;
2593 struct smk_port_label *spp;
2594 unsigned short port = 0;
2595
2596 if (address == NULL) {
2597 /*
2598 * This operation is changing the Smack information
2599 * on the bound socket. Take the changes to the port
2600 * as well.
2601 */
2602 list_for_each_entry(spp, &smk_ipv6_port_list, list) {
2603 if (sk != spp->smk_sock)
2604 continue;
2605 spp->smk_in = ssp->smk_in;
2606 spp->smk_out = ssp->smk_out;
2607 return;
2608 }
2609 /*
2610 * A NULL address is only used for updating existing
2611 * bound entries. If there isn't one, it's OK.
2612 */
2613 return;
2614 }
2615
2616 addr6 = (struct sockaddr_in6 *)address;
2617 port = ntohs(addr6->sin6_port);
2618 /*
2619 * This is a special case that is safely ignored.
2620 */
2621 if (port == 0)
2622 return;
2623
2624 /*
2625 * Look for an existing port list entry.
2626 * This is an indication that a port is getting reused.
2627 */
2628 list_for_each_entry(spp, &smk_ipv6_port_list, list) {
2629 if (spp->smk_port != port)
2630 continue;
2631 spp->smk_port = port;
2632 spp->smk_sock = sk;
2633 spp->smk_in = ssp->smk_in;
2634 spp->smk_out = ssp->smk_out;
2635 return;
2636 }
2637
2638 /*
2639 * A new port entry is required.
2640 */
2641 spp = kzalloc(sizeof(*spp), GFP_KERNEL);
2642 if (spp == NULL)
2643 return;
2644
2645 spp->smk_port = port;
2646 spp->smk_sock = sk;
2647 spp->smk_in = ssp->smk_in;
2648 spp->smk_out = ssp->smk_out;
2649
2650 list_add(&spp->list, &smk_ipv6_port_list);
2651 return;
2652 }
2653
2654 /**
2655 * smk_ipv6_port_check - check Smack port access
2656 * @sock: socket
2657 * @address: address
2658 *
2659 * Create or update the port list entry
2660 */
smk_ipv6_port_check(struct sock * sk,struct sockaddr_in6 * address,int act)2661 static int smk_ipv6_port_check(struct sock *sk, struct sockaddr_in6 *address,
2662 int act)
2663 {
2664 struct smk_port_label *spp;
2665 struct socket_smack *ssp = sk->sk_security;
2666 struct smack_known *skp = NULL;
2667 unsigned short port;
2668 struct smack_known *object;
2669
2670 if (act == SMK_RECEIVING) {
2671 skp = smack_ipv6host_label(address);
2672 object = ssp->smk_in;
2673 } else {
2674 skp = ssp->smk_out;
2675 object = smack_ipv6host_label(address);
2676 }
2677
2678 /*
2679 * The other end is a single label host.
2680 */
2681 if (skp != NULL && object != NULL)
2682 return smk_ipv6_check(skp, object, address, act);
2683 if (skp == NULL)
2684 skp = smack_net_ambient;
2685 if (object == NULL)
2686 object = smack_net_ambient;
2687
2688 /*
2689 * It's remote, so port lookup does no good.
2690 */
2691 if (!smk_ipv6_localhost(address))
2692 return smk_ipv6_check(skp, object, address, act);
2693
2694 /*
2695 * It's local so the send check has to have passed.
2696 */
2697 if (act == SMK_RECEIVING)
2698 return 0;
2699
2700 port = ntohs(address->sin6_port);
2701 list_for_each_entry(spp, &smk_ipv6_port_list, list) {
2702 if (spp->smk_port != port)
2703 continue;
2704 object = spp->smk_in;
2705 if (act == SMK_CONNECTING)
2706 ssp->smk_packet = spp->smk_out;
2707 break;
2708 }
2709
2710 return smk_ipv6_check(skp, object, address, act);
2711 }
2712 #endif /* SMACK_IPV6_PORT_LABELING */
2713
2714 /**
2715 * smack_inode_setsecurity - set smack xattrs
2716 * @inode: the object
2717 * @name: attribute name
2718 * @value: attribute value
2719 * @size: size of the attribute
2720 * @flags: unused
2721 *
2722 * Sets the named attribute in the appropriate blob
2723 *
2724 * Returns 0 on success, or an error code
2725 */
smack_inode_setsecurity(struct inode * inode,const char * name,const void * value,size_t size,int flags)2726 static int smack_inode_setsecurity(struct inode *inode, const char *name,
2727 const void *value, size_t size, int flags)
2728 {
2729 struct smack_known *skp;
2730 struct inode_smack *nsp = inode->i_security;
2731 struct socket_smack *ssp;
2732 struct socket *sock;
2733 int rc = 0;
2734
2735 if (value == NULL || size > SMK_LONGLABEL || size == 0)
2736 return -EINVAL;
2737
2738 skp = smk_import_entry(value, size);
2739 if (IS_ERR(skp))
2740 return PTR_ERR(skp);
2741
2742 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
2743 nsp->smk_inode = skp;
2744 nsp->smk_flags |= SMK_INODE_INSTANT;
2745 return 0;
2746 }
2747 /*
2748 * The rest of the Smack xattrs are only on sockets.
2749 */
2750 if (inode->i_sb->s_magic != SOCKFS_MAGIC)
2751 return -EOPNOTSUPP;
2752
2753 sock = SOCKET_I(inode);
2754 if (sock == NULL || sock->sk == NULL)
2755 return -EOPNOTSUPP;
2756
2757 ssp = sock->sk->sk_security;
2758
2759 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
2760 ssp->smk_in = skp;
2761 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) {
2762 ssp->smk_out = skp;
2763 if (sock->sk->sk_family == PF_INET) {
2764 rc = smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
2765 if (rc != 0)
2766 printk(KERN_WARNING
2767 "Smack: \"%s\" netlbl error %d.\n",
2768 __func__, -rc);
2769 }
2770 } else
2771 return -EOPNOTSUPP;
2772
2773 #ifdef SMACK_IPV6_PORT_LABELING
2774 if (sock->sk->sk_family == PF_INET6)
2775 smk_ipv6_port_label(sock, NULL);
2776 #endif
2777
2778 return 0;
2779 }
2780
2781 /**
2782 * smack_socket_post_create - finish socket setup
2783 * @sock: the socket
2784 * @family: protocol family
2785 * @type: unused
2786 * @protocol: unused
2787 * @kern: unused
2788 *
2789 * Sets the netlabel information on the socket
2790 *
2791 * Returns 0 on success, and error code otherwise
2792 */
smack_socket_post_create(struct socket * sock,int family,int type,int protocol,int kern)2793 static int smack_socket_post_create(struct socket *sock, int family,
2794 int type, int protocol, int kern)
2795 {
2796 struct socket_smack *ssp;
2797
2798 if (sock->sk == NULL)
2799 return 0;
2800
2801 /*
2802 * Sockets created by kernel threads receive web label.
2803 */
2804 if (unlikely(current->flags & PF_KTHREAD)) {
2805 ssp = sock->sk->sk_security;
2806 ssp->smk_in = &smack_known_web;
2807 ssp->smk_out = &smack_known_web;
2808 }
2809
2810 if (family != PF_INET)
2811 return 0;
2812 /*
2813 * Set the outbound netlbl.
2814 */
2815 return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
2816 }
2817
2818 #ifdef SMACK_IPV6_PORT_LABELING
2819 /**
2820 * smack_socket_bind - record port binding information.
2821 * @sock: the socket
2822 * @address: the port address
2823 * @addrlen: size of the address
2824 *
2825 * Records the label bound to a port.
2826 *
2827 * Returns 0
2828 */
smack_socket_bind(struct socket * sock,struct sockaddr * address,int addrlen)2829 static int smack_socket_bind(struct socket *sock, struct sockaddr *address,
2830 int addrlen)
2831 {
2832 if (sock->sk != NULL && sock->sk->sk_family == PF_INET6)
2833 smk_ipv6_port_label(sock, address);
2834 return 0;
2835 }
2836 #endif /* SMACK_IPV6_PORT_LABELING */
2837
2838 /**
2839 * smack_socket_connect - connect access check
2840 * @sock: the socket
2841 * @sap: the other end
2842 * @addrlen: size of sap
2843 *
2844 * Verifies that a connection may be possible
2845 *
2846 * Returns 0 on success, and error code otherwise
2847 */
smack_socket_connect(struct socket * sock,struct sockaddr * sap,int addrlen)2848 static int smack_socket_connect(struct socket *sock, struct sockaddr *sap,
2849 int addrlen)
2850 {
2851 int rc = 0;
2852 #if IS_ENABLED(CONFIG_IPV6)
2853 struct sockaddr_in6 *sip = (struct sockaddr_in6 *)sap;
2854 #endif
2855 #ifdef SMACK_IPV6_SECMARK_LABELING
2856 struct smack_known *rsp;
2857 struct socket_smack *ssp = sock->sk->sk_security;
2858 #endif
2859
2860 if (sock->sk == NULL)
2861 return 0;
2862
2863 switch (sock->sk->sk_family) {
2864 case PF_INET:
2865 if (addrlen < sizeof(struct sockaddr_in))
2866 return -EINVAL;
2867 rc = smack_netlabel_send(sock->sk, (struct sockaddr_in *)sap);
2868 break;
2869 case PF_INET6:
2870 if (addrlen < sizeof(struct sockaddr_in6))
2871 return -EINVAL;
2872 #ifdef SMACK_IPV6_SECMARK_LABELING
2873 rsp = smack_ipv6host_label(sip);
2874 if (rsp != NULL)
2875 rc = smk_ipv6_check(ssp->smk_out, rsp, sip,
2876 SMK_CONNECTING);
2877 #endif
2878 #ifdef SMACK_IPV6_PORT_LABELING
2879 rc = smk_ipv6_port_check(sock->sk, sip, SMK_CONNECTING);
2880 #endif
2881 break;
2882 }
2883 return rc;
2884 }
2885
2886 /**
2887 * smack_flags_to_may - convert S_ to MAY_ values
2888 * @flags: the S_ value
2889 *
2890 * Returns the equivalent MAY_ value
2891 */
smack_flags_to_may(int flags)2892 static int smack_flags_to_may(int flags)
2893 {
2894 int may = 0;
2895
2896 if (flags & S_IRUGO)
2897 may |= MAY_READ;
2898 if (flags & S_IWUGO)
2899 may |= MAY_WRITE;
2900 if (flags & S_IXUGO)
2901 may |= MAY_EXEC;
2902
2903 return may;
2904 }
2905
2906 /**
2907 * smack_msg_msg_alloc_security - Set the security blob for msg_msg
2908 * @msg: the object
2909 *
2910 * Returns 0
2911 */
smack_msg_msg_alloc_security(struct msg_msg * msg)2912 static int smack_msg_msg_alloc_security(struct msg_msg *msg)
2913 {
2914 struct smack_known *skp = smk_of_current();
2915
2916 msg->security = skp;
2917 return 0;
2918 }
2919
2920 /**
2921 * smack_msg_msg_free_security - Clear the security blob for msg_msg
2922 * @msg: the object
2923 *
2924 * Clears the blob pointer
2925 */
smack_msg_msg_free_security(struct msg_msg * msg)2926 static void smack_msg_msg_free_security(struct msg_msg *msg)
2927 {
2928 msg->security = NULL;
2929 }
2930
2931 /**
2932 * smack_of_shm - the smack pointer for the shm
2933 * @shp: the object
2934 *
2935 * Returns a pointer to the smack value
2936 */
smack_of_shm(struct shmid_kernel * shp)2937 static struct smack_known *smack_of_shm(struct shmid_kernel *shp)
2938 {
2939 return (struct smack_known *)shp->shm_perm.security;
2940 }
2941
2942 /**
2943 * smack_shm_alloc_security - Set the security blob for shm
2944 * @shp: the object
2945 *
2946 * Returns 0
2947 */
smack_shm_alloc_security(struct shmid_kernel * shp)2948 static int smack_shm_alloc_security(struct shmid_kernel *shp)
2949 {
2950 struct kern_ipc_perm *isp = &shp->shm_perm;
2951 struct smack_known *skp = smk_of_current();
2952
2953 isp->security = skp;
2954 return 0;
2955 }
2956
2957 /**
2958 * smack_shm_free_security - Clear the security blob for shm
2959 * @shp: the object
2960 *
2961 * Clears the blob pointer
2962 */
smack_shm_free_security(struct shmid_kernel * shp)2963 static void smack_shm_free_security(struct shmid_kernel *shp)
2964 {
2965 struct kern_ipc_perm *isp = &shp->shm_perm;
2966
2967 isp->security = NULL;
2968 }
2969
2970 /**
2971 * smk_curacc_shm : check if current has access on shm
2972 * @shp : the object
2973 * @access : access requested
2974 *
2975 * Returns 0 if current has the requested access, error code otherwise
2976 */
smk_curacc_shm(struct shmid_kernel * shp,int access)2977 static int smk_curacc_shm(struct shmid_kernel *shp, int access)
2978 {
2979 struct smack_known *ssp = smack_of_shm(shp);
2980 struct smk_audit_info ad;
2981 int rc;
2982
2983 #ifdef CONFIG_AUDIT
2984 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
2985 ad.a.u.ipc_id = shp->shm_perm.id;
2986 #endif
2987 rc = smk_curacc(ssp, access, &ad);
2988 rc = smk_bu_current("shm", ssp, access, rc);
2989 return rc;
2990 }
2991
2992 /**
2993 * smack_shm_associate - Smack access check for shm
2994 * @shp: the object
2995 * @shmflg: access requested
2996 *
2997 * Returns 0 if current has the requested access, error code otherwise
2998 */
smack_shm_associate(struct shmid_kernel * shp,int shmflg)2999 static int smack_shm_associate(struct shmid_kernel *shp, int shmflg)
3000 {
3001 int may;
3002
3003 may = smack_flags_to_may(shmflg);
3004 return smk_curacc_shm(shp, may);
3005 }
3006
3007 /**
3008 * smack_shm_shmctl - Smack access check for shm
3009 * @shp: the object
3010 * @cmd: what it wants to do
3011 *
3012 * Returns 0 if current has the requested access, error code otherwise
3013 */
smack_shm_shmctl(struct shmid_kernel * shp,int cmd)3014 static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd)
3015 {
3016 int may;
3017
3018 switch (cmd) {
3019 case IPC_STAT:
3020 case SHM_STAT:
3021 may = MAY_READ;
3022 break;
3023 case IPC_SET:
3024 case SHM_LOCK:
3025 case SHM_UNLOCK:
3026 case IPC_RMID:
3027 may = MAY_READWRITE;
3028 break;
3029 case IPC_INFO:
3030 case SHM_INFO:
3031 /*
3032 * System level information.
3033 */
3034 return 0;
3035 default:
3036 return -EINVAL;
3037 }
3038 return smk_curacc_shm(shp, may);
3039 }
3040
3041 /**
3042 * smack_shm_shmat - Smack access for shmat
3043 * @shp: the object
3044 * @shmaddr: unused
3045 * @shmflg: access requested
3046 *
3047 * Returns 0 if current has the requested access, error code otherwise
3048 */
smack_shm_shmat(struct shmid_kernel * shp,char __user * shmaddr,int shmflg)3049 static int smack_shm_shmat(struct shmid_kernel *shp, char __user *shmaddr,
3050 int shmflg)
3051 {
3052 int may;
3053
3054 may = smack_flags_to_may(shmflg);
3055 return smk_curacc_shm(shp, may);
3056 }
3057
3058 /**
3059 * smack_of_sem - the smack pointer for the sem
3060 * @sma: the object
3061 *
3062 * Returns a pointer to the smack value
3063 */
smack_of_sem(struct sem_array * sma)3064 static struct smack_known *smack_of_sem(struct sem_array *sma)
3065 {
3066 return (struct smack_known *)sma->sem_perm.security;
3067 }
3068
3069 /**
3070 * smack_sem_alloc_security - Set the security blob for sem
3071 * @sma: the object
3072 *
3073 * Returns 0
3074 */
smack_sem_alloc_security(struct sem_array * sma)3075 static int smack_sem_alloc_security(struct sem_array *sma)
3076 {
3077 struct kern_ipc_perm *isp = &sma->sem_perm;
3078 struct smack_known *skp = smk_of_current();
3079
3080 isp->security = skp;
3081 return 0;
3082 }
3083
3084 /**
3085 * smack_sem_free_security - Clear the security blob for sem
3086 * @sma: the object
3087 *
3088 * Clears the blob pointer
3089 */
smack_sem_free_security(struct sem_array * sma)3090 static void smack_sem_free_security(struct sem_array *sma)
3091 {
3092 struct kern_ipc_perm *isp = &sma->sem_perm;
3093
3094 isp->security = NULL;
3095 }
3096
3097 /**
3098 * smk_curacc_sem : check if current has access on sem
3099 * @sma : the object
3100 * @access : access requested
3101 *
3102 * Returns 0 if current has the requested access, error code otherwise
3103 */
smk_curacc_sem(struct sem_array * sma,int access)3104 static int smk_curacc_sem(struct sem_array *sma, int access)
3105 {
3106 struct smack_known *ssp = smack_of_sem(sma);
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 = sma->sem_perm.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 * @sma: the object
3122 * @semflg: access requested
3123 *
3124 * Returns 0 if current has the requested access, error code otherwise
3125 */
smack_sem_associate(struct sem_array * sma,int semflg)3126 static int smack_sem_associate(struct sem_array *sma, int semflg)
3127 {
3128 int may;
3129
3130 may = smack_flags_to_may(semflg);
3131 return smk_curacc_sem(sma, may);
3132 }
3133
3134 /**
3135 * smack_sem_shmctl - Smack access check for sem
3136 * @sma: the object
3137 * @cmd: what it wants to do
3138 *
3139 * Returns 0 if current has the requested access, error code otherwise
3140 */
smack_sem_semctl(struct sem_array * sma,int cmd)3141 static int smack_sem_semctl(struct sem_array *sma, 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 may = MAY_READ;
3154 break;
3155 case SETVAL:
3156 case SETALL:
3157 case IPC_RMID:
3158 case IPC_SET:
3159 may = MAY_READWRITE;
3160 break;
3161 case IPC_INFO:
3162 case SEM_INFO:
3163 /*
3164 * System level information
3165 */
3166 return 0;
3167 default:
3168 return -EINVAL;
3169 }
3170
3171 return smk_curacc_sem(sma, may);
3172 }
3173
3174 /**
3175 * smack_sem_semop - Smack checks of semaphore operations
3176 * @sma: the object
3177 * @sops: unused
3178 * @nsops: unused
3179 * @alter: unused
3180 *
3181 * Treated as read and write in all cases.
3182 *
3183 * Returns 0 if access is allowed, error code otherwise
3184 */
smack_sem_semop(struct sem_array * sma,struct sembuf * sops,unsigned nsops,int alter)3185 static int smack_sem_semop(struct sem_array *sma, struct sembuf *sops,
3186 unsigned nsops, int alter)
3187 {
3188 return smk_curacc_sem(sma, MAY_READWRITE);
3189 }
3190
3191 /**
3192 * smack_msg_alloc_security - Set the security blob for msg
3193 * @msq: the object
3194 *
3195 * Returns 0
3196 */
smack_msg_queue_alloc_security(struct msg_queue * msq)3197 static int smack_msg_queue_alloc_security(struct msg_queue *msq)
3198 {
3199 struct kern_ipc_perm *kisp = &msq->q_perm;
3200 struct smack_known *skp = smk_of_current();
3201
3202 kisp->security = skp;
3203 return 0;
3204 }
3205
3206 /**
3207 * smack_msg_free_security - Clear the security blob for msg
3208 * @msq: the object
3209 *
3210 * Clears the blob pointer
3211 */
smack_msg_queue_free_security(struct msg_queue * msq)3212 static void smack_msg_queue_free_security(struct msg_queue *msq)
3213 {
3214 struct kern_ipc_perm *kisp = &msq->q_perm;
3215
3216 kisp->security = NULL;
3217 }
3218
3219 /**
3220 * smack_of_msq - the smack pointer for the msq
3221 * @msq: the object
3222 *
3223 * Returns a pointer to the smack label entry
3224 */
smack_of_msq(struct msg_queue * msq)3225 static struct smack_known *smack_of_msq(struct msg_queue *msq)
3226 {
3227 return (struct smack_known *)msq->q_perm.security;
3228 }
3229
3230 /**
3231 * smk_curacc_msq : helper to check if current has access on msq
3232 * @msq : the msq
3233 * @access : access requested
3234 *
3235 * return 0 if current has access, error otherwise
3236 */
smk_curacc_msq(struct msg_queue * msq,int access)3237 static int smk_curacc_msq(struct msg_queue *msq, int access)
3238 {
3239 struct smack_known *msp = smack_of_msq(msq);
3240 struct smk_audit_info ad;
3241 int rc;
3242
3243 #ifdef CONFIG_AUDIT
3244 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
3245 ad.a.u.ipc_id = msq->q_perm.id;
3246 #endif
3247 rc = smk_curacc(msp, access, &ad);
3248 rc = smk_bu_current("msq", msp, access, rc);
3249 return rc;
3250 }
3251
3252 /**
3253 * smack_msg_queue_associate - Smack access check for msg_queue
3254 * @msq: the object
3255 * @msqflg: access requested
3256 *
3257 * Returns 0 if current has the requested access, error code otherwise
3258 */
smack_msg_queue_associate(struct msg_queue * msq,int msqflg)3259 static int smack_msg_queue_associate(struct msg_queue *msq, int msqflg)
3260 {
3261 int may;
3262
3263 may = smack_flags_to_may(msqflg);
3264 return smk_curacc_msq(msq, may);
3265 }
3266
3267 /**
3268 * smack_msg_queue_msgctl - Smack access check for msg_queue
3269 * @msq: the object
3270 * @cmd: what it wants to do
3271 *
3272 * Returns 0 if current has the requested access, error code otherwise
3273 */
smack_msg_queue_msgctl(struct msg_queue * msq,int cmd)3274 static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd)
3275 {
3276 int may;
3277
3278 switch (cmd) {
3279 case IPC_STAT:
3280 case MSG_STAT:
3281 may = MAY_READ;
3282 break;
3283 case IPC_SET:
3284 case IPC_RMID:
3285 may = MAY_READWRITE;
3286 break;
3287 case IPC_INFO:
3288 case MSG_INFO:
3289 /*
3290 * System level information
3291 */
3292 return 0;
3293 default:
3294 return -EINVAL;
3295 }
3296
3297 return smk_curacc_msq(msq, may);
3298 }
3299
3300 /**
3301 * smack_msg_queue_msgsnd - Smack access check for msg_queue
3302 * @msq: the object
3303 * @msg: unused
3304 * @msqflg: access requested
3305 *
3306 * Returns 0 if current has the requested access, error code otherwise
3307 */
smack_msg_queue_msgsnd(struct msg_queue * msq,struct msg_msg * msg,int msqflg)3308 static int smack_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg,
3309 int msqflg)
3310 {
3311 int may;
3312
3313 may = smack_flags_to_may(msqflg);
3314 return smk_curacc_msq(msq, may);
3315 }
3316
3317 /**
3318 * smack_msg_queue_msgsnd - Smack access check for msg_queue
3319 * @msq: the object
3320 * @msg: unused
3321 * @target: unused
3322 * @type: unused
3323 * @mode: unused
3324 *
3325 * Returns 0 if current has read and write access, error code otherwise
3326 */
smack_msg_queue_msgrcv(struct msg_queue * msq,struct msg_msg * msg,struct task_struct * target,long type,int mode)3327 static int smack_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
3328 struct task_struct *target, long type, int mode)
3329 {
3330 return smk_curacc_msq(msq, MAY_READWRITE);
3331 }
3332
3333 /**
3334 * smack_ipc_permission - Smack access for ipc_permission()
3335 * @ipp: the object permissions
3336 * @flag: access requested
3337 *
3338 * Returns 0 if current has read and write access, error code otherwise
3339 */
smack_ipc_permission(struct kern_ipc_perm * ipp,short flag)3340 static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag)
3341 {
3342 struct smack_known *iskp = ipp->security;
3343 int may = smack_flags_to_may(flag);
3344 struct smk_audit_info ad;
3345 int rc;
3346
3347 #ifdef CONFIG_AUDIT
3348 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
3349 ad.a.u.ipc_id = ipp->id;
3350 #endif
3351 rc = smk_curacc(iskp, may, &ad);
3352 rc = smk_bu_current("svipc", iskp, may, rc);
3353 return rc;
3354 }
3355
3356 /**
3357 * smack_ipc_getsecid - Extract smack security id
3358 * @ipp: the object permissions
3359 * @secid: where result will be saved
3360 */
smack_ipc_getsecid(struct kern_ipc_perm * ipp,u32 * secid)3361 static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid)
3362 {
3363 struct smack_known *iskp = ipp->security;
3364
3365 *secid = iskp->smk_secid;
3366 }
3367
3368 /**
3369 * smack_d_instantiate - Make sure the blob is correct on an inode
3370 * @opt_dentry: dentry where inode will be attached
3371 * @inode: the object
3372 *
3373 * Set the inode's security blob if it hasn't been done already.
3374 */
smack_d_instantiate(struct dentry * opt_dentry,struct inode * inode)3375 static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
3376 {
3377 struct super_block *sbp;
3378 struct superblock_smack *sbsp;
3379 struct inode_smack *isp;
3380 struct smack_known *skp;
3381 struct smack_known *ckp = smk_of_current();
3382 struct smack_known *final;
3383 char trattr[TRANS_TRUE_SIZE];
3384 int transflag = 0;
3385 int rc;
3386 struct dentry *dp;
3387
3388 if (inode == NULL)
3389 return;
3390
3391 isp = inode->i_security;
3392
3393 mutex_lock(&isp->smk_lock);
3394 /*
3395 * If the inode is already instantiated
3396 * take the quick way out
3397 */
3398 if (isp->smk_flags & SMK_INODE_INSTANT)
3399 goto unlockandout;
3400
3401 sbp = inode->i_sb;
3402 sbsp = sbp->s_security;
3403 /*
3404 * We're going to use the superblock default label
3405 * if there's no label on the file.
3406 */
3407 final = sbsp->smk_default;
3408
3409 /*
3410 * If this is the root inode the superblock
3411 * may be in the process of initialization.
3412 * If that is the case use the root value out
3413 * of the superblock.
3414 */
3415 if (opt_dentry->d_parent == opt_dentry) {
3416 switch (sbp->s_magic) {
3417 case CGROUP_SUPER_MAGIC:
3418 /*
3419 * The cgroup filesystem is never mounted,
3420 * so there's no opportunity to set the mount
3421 * options.
3422 */
3423 sbsp->smk_root = &smack_known_star;
3424 sbsp->smk_default = &smack_known_star;
3425 isp->smk_inode = sbsp->smk_root;
3426 break;
3427 case TMPFS_MAGIC:
3428 /*
3429 * What about shmem/tmpfs anonymous files with dentry
3430 * obtained from d_alloc_pseudo()?
3431 */
3432 isp->smk_inode = smk_of_current();
3433 break;
3434 case PIPEFS_MAGIC:
3435 isp->smk_inode = smk_of_current();
3436 break;
3437 default:
3438 isp->smk_inode = sbsp->smk_root;
3439 break;
3440 }
3441 isp->smk_flags |= SMK_INODE_INSTANT;
3442 goto unlockandout;
3443 }
3444
3445 /*
3446 * This is pretty hackish.
3447 * Casey says that we shouldn't have to do
3448 * file system specific code, but it does help
3449 * with keeping it simple.
3450 */
3451 switch (sbp->s_magic) {
3452 case SMACK_MAGIC:
3453 case PIPEFS_MAGIC:
3454 case SOCKFS_MAGIC:
3455 case CGROUP_SUPER_MAGIC:
3456 /*
3457 * Casey says that it's a little embarrassing
3458 * that the smack file system doesn't do
3459 * extended attributes.
3460 *
3461 * Casey says pipes are easy (?)
3462 *
3463 * Socket access is controlled by the socket
3464 * structures associated with the task involved.
3465 *
3466 * Cgroupfs is special
3467 */
3468 final = &smack_known_star;
3469 break;
3470 case DEVPTS_SUPER_MAGIC:
3471 /*
3472 * devpts seems content with the label of the task.
3473 * Programs that change smack have to treat the
3474 * pty with respect.
3475 */
3476 final = ckp;
3477 break;
3478 case PROC_SUPER_MAGIC:
3479 /*
3480 * Casey says procfs appears not to care.
3481 * The superblock default suffices.
3482 */
3483 break;
3484 case TMPFS_MAGIC:
3485 /*
3486 * Device labels should come from the filesystem,
3487 * but watch out, because they're volitile,
3488 * getting recreated on every reboot.
3489 */
3490 final = &smack_known_star;
3491 /*
3492 * No break.
3493 *
3494 * If a smack value has been set we want to use it,
3495 * but since tmpfs isn't giving us the opportunity
3496 * to set mount options simulate setting the
3497 * superblock default.
3498 */
3499 default:
3500 /*
3501 * This isn't an understood special case.
3502 * Get the value from the xattr.
3503 */
3504
3505 /*
3506 * UNIX domain sockets use lower level socket data.
3507 */
3508 if (S_ISSOCK(inode->i_mode)) {
3509 final = &smack_known_star;
3510 break;
3511 }
3512 /*
3513 * No xattr support means, alas, no SMACK label.
3514 * Use the aforeapplied default.
3515 * It would be curious if the label of the task
3516 * does not match that assigned.
3517 */
3518 if (!(inode->i_opflags & IOP_XATTR))
3519 break;
3520 /*
3521 * Get the dentry for xattr.
3522 */
3523 dp = dget(opt_dentry);
3524 skp = smk_fetch(XATTR_NAME_SMACK, inode, dp);
3525 if (!IS_ERR_OR_NULL(skp))
3526 final = skp;
3527
3528 /*
3529 * Transmuting directory
3530 */
3531 if (S_ISDIR(inode->i_mode)) {
3532 /*
3533 * If this is a new directory and the label was
3534 * transmuted when the inode was initialized
3535 * set the transmute attribute on the directory
3536 * and mark the inode.
3537 *
3538 * If there is a transmute attribute on the
3539 * directory mark the inode.
3540 */
3541 if (isp->smk_flags & SMK_INODE_CHANGED) {
3542 isp->smk_flags &= ~SMK_INODE_CHANGED;
3543 rc = __vfs_setxattr(dp, inode,
3544 XATTR_NAME_SMACKTRANSMUTE,
3545 TRANS_TRUE, TRANS_TRUE_SIZE,
3546 0);
3547 } else {
3548 rc = __vfs_getxattr(dp, inode,
3549 XATTR_NAME_SMACKTRANSMUTE, trattr,
3550 TRANS_TRUE_SIZE);
3551 if (rc >= 0 && strncmp(trattr, TRANS_TRUE,
3552 TRANS_TRUE_SIZE) != 0)
3553 rc = -EINVAL;
3554 }
3555 if (rc >= 0)
3556 transflag = SMK_INODE_TRANSMUTE;
3557 }
3558 /*
3559 * Don't let the exec or mmap label be "*" or "@".
3560 */
3561 skp = smk_fetch(XATTR_NAME_SMACKEXEC, inode, dp);
3562 if (IS_ERR(skp) || skp == &smack_known_star ||
3563 skp == &smack_known_web)
3564 skp = NULL;
3565 isp->smk_task = skp;
3566
3567 skp = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp);
3568 if (IS_ERR(skp) || skp == &smack_known_star ||
3569 skp == &smack_known_web)
3570 skp = NULL;
3571 isp->smk_mmap = skp;
3572
3573 dput(dp);
3574 break;
3575 }
3576
3577 if (final == NULL)
3578 isp->smk_inode = ckp;
3579 else
3580 isp->smk_inode = final;
3581
3582 isp->smk_flags |= (SMK_INODE_INSTANT | transflag);
3583
3584 unlockandout:
3585 mutex_unlock(&isp->smk_lock);
3586 return;
3587 }
3588
3589 /**
3590 * smack_getprocattr - Smack process attribute access
3591 * @p: the object task
3592 * @name: the name of the attribute in /proc/.../attr
3593 * @value: where to put the result
3594 *
3595 * Places a copy of the task Smack into value
3596 *
3597 * Returns the length of the smack label or an error code
3598 */
smack_getprocattr(struct task_struct * p,char * name,char ** value)3599 static int smack_getprocattr(struct task_struct *p, char *name, char **value)
3600 {
3601 struct smack_known *skp = smk_of_task_struct(p);
3602 char *cp;
3603 int slen;
3604
3605 if (strcmp(name, "current") != 0)
3606 return -EINVAL;
3607
3608 cp = kstrdup(skp->smk_known, GFP_KERNEL);
3609 if (cp == NULL)
3610 return -ENOMEM;
3611
3612 slen = strlen(cp);
3613 *value = cp;
3614 return slen;
3615 }
3616
3617 /**
3618 * smack_setprocattr - Smack process attribute setting
3619 * @p: the object task
3620 * @name: the name of the attribute in /proc/.../attr
3621 * @value: the value to set
3622 * @size: the size of the value
3623 *
3624 * Sets the Smack value of the task. Only setting self
3625 * is permitted and only with privilege
3626 *
3627 * Returns the length of the smack label or an error code
3628 */
smack_setprocattr(struct task_struct * p,char * name,void * value,size_t size)3629 static int smack_setprocattr(struct task_struct *p, char *name,
3630 void *value, size_t size)
3631 {
3632 struct task_smack *tsp = current_security();
3633 struct cred *new;
3634 struct smack_known *skp;
3635 struct smack_known_list_elem *sklep;
3636 int rc;
3637
3638 /*
3639 * Changing another process' Smack value is too dangerous
3640 * and supports no sane use case.
3641 */
3642 if (p != current)
3643 return -EPERM;
3644
3645 if (!smack_privileged(CAP_MAC_ADMIN) && list_empty(&tsp->smk_relabel))
3646 return -EPERM;
3647
3648 if (value == NULL || size == 0 || size >= SMK_LONGLABEL)
3649 return -EINVAL;
3650
3651 if (strcmp(name, "current") != 0)
3652 return -EINVAL;
3653
3654 skp = smk_import_entry(value, size);
3655 if (IS_ERR(skp))
3656 return PTR_ERR(skp);
3657
3658 /*
3659 * No process is ever allowed the web ("@") label.
3660 */
3661 if (skp == &smack_known_web)
3662 return -EPERM;
3663
3664 if (!smack_privileged(CAP_MAC_ADMIN)) {
3665 rc = -EPERM;
3666 list_for_each_entry(sklep, &tsp->smk_relabel, list)
3667 if (sklep->smk_label == skp) {
3668 rc = 0;
3669 break;
3670 }
3671 if (rc)
3672 return rc;
3673 }
3674
3675 new = prepare_creds();
3676 if (new == NULL)
3677 return -ENOMEM;
3678
3679 tsp = new->security;
3680 tsp->smk_task = skp;
3681 /*
3682 * process can change its label only once
3683 */
3684 smk_destroy_label_list(&tsp->smk_relabel);
3685
3686 commit_creds(new);
3687 return size;
3688 }
3689
3690 /**
3691 * smack_unix_stream_connect - Smack access on UDS
3692 * @sock: one sock
3693 * @other: the other sock
3694 * @newsk: unused
3695 *
3696 * Return 0 if a subject with the smack of sock could access
3697 * an object with the smack of other, otherwise an error code
3698 */
smack_unix_stream_connect(struct sock * sock,struct sock * other,struct sock * newsk)3699 static int smack_unix_stream_connect(struct sock *sock,
3700 struct sock *other, struct sock *newsk)
3701 {
3702 struct smack_known *skp;
3703 struct smack_known *okp;
3704 struct socket_smack *ssp = sock->sk_security;
3705 struct socket_smack *osp = other->sk_security;
3706 struct socket_smack *nsp = newsk->sk_security;
3707 struct smk_audit_info ad;
3708 int rc = 0;
3709 #ifdef CONFIG_AUDIT
3710 struct lsm_network_audit net;
3711 #endif
3712
3713 if (!smack_privileged(CAP_MAC_OVERRIDE)) {
3714 skp = ssp->smk_out;
3715 okp = osp->smk_in;
3716 #ifdef CONFIG_AUDIT
3717 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
3718 smk_ad_setfield_u_net_sk(&ad, other);
3719 #endif
3720 rc = smk_access(skp, okp, MAY_WRITE, &ad);
3721 rc = smk_bu_note("UDS connect", skp, okp, MAY_WRITE, rc);
3722 if (rc == 0) {
3723 okp = osp->smk_out;
3724 skp = ssp->smk_in;
3725 rc = smk_access(okp, skp, MAY_WRITE, &ad);
3726 rc = smk_bu_note("UDS connect", okp, skp,
3727 MAY_WRITE, rc);
3728 }
3729 }
3730
3731 /*
3732 * Cross reference the peer labels for SO_PEERSEC.
3733 */
3734 if (rc == 0) {
3735 nsp->smk_packet = ssp->smk_out;
3736 ssp->smk_packet = osp->smk_out;
3737 }
3738
3739 return rc;
3740 }
3741
3742 /**
3743 * smack_unix_may_send - Smack access on UDS
3744 * @sock: one socket
3745 * @other: the other socket
3746 *
3747 * Return 0 if a subject with the smack of sock could access
3748 * an object with the smack of other, otherwise an error code
3749 */
smack_unix_may_send(struct socket * sock,struct socket * other)3750 static int smack_unix_may_send(struct socket *sock, struct socket *other)
3751 {
3752 struct socket_smack *ssp = sock->sk->sk_security;
3753 struct socket_smack *osp = other->sk->sk_security;
3754 struct smk_audit_info ad;
3755 int rc;
3756
3757 #ifdef CONFIG_AUDIT
3758 struct lsm_network_audit net;
3759
3760 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
3761 smk_ad_setfield_u_net_sk(&ad, other->sk);
3762 #endif
3763
3764 if (smack_privileged(CAP_MAC_OVERRIDE))
3765 return 0;
3766
3767 rc = smk_access(ssp->smk_out, osp->smk_in, MAY_WRITE, &ad);
3768 rc = smk_bu_note("UDS send", ssp->smk_out, osp->smk_in, MAY_WRITE, rc);
3769 return rc;
3770 }
3771
3772 /**
3773 * smack_socket_sendmsg - Smack check based on destination host
3774 * @sock: the socket
3775 * @msg: the message
3776 * @size: the size of the message
3777 *
3778 * Return 0 if the current subject can write to the destination host.
3779 * For IPv4 this is only a question if the destination is a single label host.
3780 * For IPv6 this is a check against the label of the port.
3781 */
smack_socket_sendmsg(struct socket * sock,struct msghdr * msg,int size)3782 static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3783 int size)
3784 {
3785 struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name;
3786 #if IS_ENABLED(CONFIG_IPV6)
3787 struct sockaddr_in6 *sap = (struct sockaddr_in6 *) msg->msg_name;
3788 #endif
3789 #ifdef SMACK_IPV6_SECMARK_LABELING
3790 struct socket_smack *ssp = sock->sk->sk_security;
3791 struct smack_known *rsp;
3792 #endif
3793 int rc = 0;
3794
3795 /*
3796 * Perfectly reasonable for this to be NULL
3797 */
3798 if (sip == NULL)
3799 return 0;
3800
3801 switch (sock->sk->sk_family) {
3802 case AF_INET:
3803 rc = smack_netlabel_send(sock->sk, sip);
3804 break;
3805 case AF_INET6:
3806 #ifdef SMACK_IPV6_SECMARK_LABELING
3807 rsp = smack_ipv6host_label(sap);
3808 if (rsp != NULL)
3809 rc = smk_ipv6_check(ssp->smk_out, rsp, sap,
3810 SMK_CONNECTING);
3811 #endif
3812 #ifdef SMACK_IPV6_PORT_LABELING
3813 rc = smk_ipv6_port_check(sock->sk, sap, SMK_SENDING);
3814 #endif
3815 break;
3816 }
3817 return rc;
3818 }
3819
3820 /**
3821 * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat pair to smack
3822 * @sap: netlabel secattr
3823 * @ssp: socket security information
3824 *
3825 * Returns a pointer to a Smack label entry found on the label list.
3826 */
smack_from_secattr(struct netlbl_lsm_secattr * sap,struct socket_smack * ssp)3827 static struct smack_known *smack_from_secattr(struct netlbl_lsm_secattr *sap,
3828 struct socket_smack *ssp)
3829 {
3830 struct smack_known *skp;
3831 int found = 0;
3832 int acat;
3833 int kcat;
3834
3835 if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) {
3836 /*
3837 * Looks like a CIPSO packet.
3838 * If there are flags but no level netlabel isn't
3839 * behaving the way we expect it to.
3840 *
3841 * Look it up in the label table
3842 * Without guidance regarding the smack value
3843 * for the packet fall back on the network
3844 * ambient value.
3845 */
3846 rcu_read_lock();
3847 list_for_each_entry(skp, &smack_known_list, list) {
3848 if (sap->attr.mls.lvl != skp->smk_netlabel.attr.mls.lvl)
3849 continue;
3850 /*
3851 * Compare the catsets. Use the netlbl APIs.
3852 */
3853 if ((sap->flags & NETLBL_SECATTR_MLS_CAT) == 0) {
3854 if ((skp->smk_netlabel.flags &
3855 NETLBL_SECATTR_MLS_CAT) == 0)
3856 found = 1;
3857 break;
3858 }
3859 for (acat = -1, kcat = -1; acat == kcat; ) {
3860 acat = netlbl_catmap_walk(sap->attr.mls.cat,
3861 acat + 1);
3862 kcat = netlbl_catmap_walk(
3863 skp->smk_netlabel.attr.mls.cat,
3864 kcat + 1);
3865 if (acat < 0 || kcat < 0)
3866 break;
3867 }
3868 if (acat == kcat) {
3869 found = 1;
3870 break;
3871 }
3872 }
3873 rcu_read_unlock();
3874
3875 if (found)
3876 return skp;
3877
3878 if (ssp != NULL && ssp->smk_in == &smack_known_star)
3879 return &smack_known_web;
3880 return &smack_known_star;
3881 }
3882 if ((sap->flags & NETLBL_SECATTR_SECID) != 0) {
3883 /*
3884 * Looks like a fallback, which gives us a secid.
3885 */
3886 skp = smack_from_secid(sap->attr.secid);
3887 /*
3888 * This has got to be a bug because it is
3889 * impossible to specify a fallback without
3890 * specifying the label, which will ensure
3891 * it has a secid, and the only way to get a
3892 * secid is from a fallback.
3893 */
3894 BUG_ON(skp == NULL);
3895 return skp;
3896 }
3897 /*
3898 * Without guidance regarding the smack value
3899 * for the packet fall back on the network
3900 * ambient value.
3901 */
3902 return smack_net_ambient;
3903 }
3904
3905 #if IS_ENABLED(CONFIG_IPV6)
smk_skb_to_addr_ipv6(struct sk_buff * skb,struct sockaddr_in6 * sip)3906 static int smk_skb_to_addr_ipv6(struct sk_buff *skb, struct sockaddr_in6 *sip)
3907 {
3908 u8 nexthdr;
3909 int offset;
3910 int proto = -EINVAL;
3911 struct ipv6hdr _ipv6h;
3912 struct ipv6hdr *ip6;
3913 __be16 frag_off;
3914 struct tcphdr _tcph, *th;
3915 struct udphdr _udph, *uh;
3916 struct dccp_hdr _dccph, *dh;
3917
3918 sip->sin6_port = 0;
3919
3920 offset = skb_network_offset(skb);
3921 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3922 if (ip6 == NULL)
3923 return -EINVAL;
3924 sip->sin6_addr = ip6->saddr;
3925
3926 nexthdr = ip6->nexthdr;
3927 offset += sizeof(_ipv6h);
3928 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
3929 if (offset < 0)
3930 return -EINVAL;
3931
3932 proto = nexthdr;
3933 switch (proto) {
3934 case IPPROTO_TCP:
3935 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3936 if (th != NULL)
3937 sip->sin6_port = th->source;
3938 break;
3939 case IPPROTO_UDP:
3940 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3941 if (uh != NULL)
3942 sip->sin6_port = uh->source;
3943 break;
3944 case IPPROTO_DCCP:
3945 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3946 if (dh != NULL)
3947 sip->sin6_port = dh->dccph_sport;
3948 break;
3949 }
3950 return proto;
3951 }
3952 #endif /* CONFIG_IPV6 */
3953
3954 /**
3955 * smack_socket_sock_rcv_skb - Smack packet delivery access check
3956 * @sk: socket
3957 * @skb: packet
3958 *
3959 * Returns 0 if the packet should be delivered, an error code otherwise
3960 */
smack_socket_sock_rcv_skb(struct sock * sk,struct sk_buff * skb)3961 static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
3962 {
3963 struct netlbl_lsm_secattr secattr;
3964 struct socket_smack *ssp = sk->sk_security;
3965 struct smack_known *skp = NULL;
3966 int rc = 0;
3967 struct smk_audit_info ad;
3968 #ifdef CONFIG_AUDIT
3969 struct lsm_network_audit net;
3970 #endif
3971 #if IS_ENABLED(CONFIG_IPV6)
3972 struct sockaddr_in6 sadd;
3973 int proto;
3974 #endif /* CONFIG_IPV6 */
3975
3976 switch (sk->sk_family) {
3977 case PF_INET:
3978 #ifdef CONFIG_SECURITY_SMACK_NETFILTER
3979 /*
3980 * If there is a secmark use it rather than the CIPSO label.
3981 * If there is no secmark fall back to CIPSO.
3982 * The secmark is assumed to reflect policy better.
3983 */
3984 if (skb && skb->secmark != 0) {
3985 skp = smack_from_secid(skb->secmark);
3986 goto access_check;
3987 }
3988 #endif /* CONFIG_SECURITY_SMACK_NETFILTER */
3989 /*
3990 * Translate what netlabel gave us.
3991 */
3992 netlbl_secattr_init(&secattr);
3993
3994 rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr);
3995 if (rc == 0)
3996 skp = smack_from_secattr(&secattr, ssp);
3997 else
3998 skp = smack_net_ambient;
3999
4000 netlbl_secattr_destroy(&secattr);
4001
4002 #ifdef CONFIG_SECURITY_SMACK_NETFILTER
4003 access_check:
4004 #endif
4005 #ifdef CONFIG_AUDIT
4006 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
4007 ad.a.u.net->family = sk->sk_family;
4008 ad.a.u.net->netif = skb->skb_iif;
4009 ipv4_skb_to_auditdata(skb, &ad.a, NULL);
4010 #endif
4011 /*
4012 * Receiving a packet requires that the other end
4013 * be able to write here. Read access is not required.
4014 * This is the simplist possible security model
4015 * for networking.
4016 */
4017 rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
4018 rc = smk_bu_note("IPv4 delivery", skp, ssp->smk_in,
4019 MAY_WRITE, rc);
4020 if (rc != 0)
4021 netlbl_skbuff_err(skb, sk->sk_family, rc, 0);
4022 break;
4023 #if IS_ENABLED(CONFIG_IPV6)
4024 case PF_INET6:
4025 proto = smk_skb_to_addr_ipv6(skb, &sadd);
4026 if (proto != IPPROTO_UDP && proto != IPPROTO_TCP)
4027 break;
4028 #ifdef SMACK_IPV6_SECMARK_LABELING
4029 if (skb && skb->secmark != 0)
4030 skp = smack_from_secid(skb->secmark);
4031 else
4032 skp = smack_ipv6host_label(&sadd);
4033 if (skp == NULL)
4034 skp = smack_net_ambient;
4035 #ifdef CONFIG_AUDIT
4036 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
4037 ad.a.u.net->family = sk->sk_family;
4038 ad.a.u.net->netif = skb->skb_iif;
4039 ipv6_skb_to_auditdata(skb, &ad.a, NULL);
4040 #endif /* CONFIG_AUDIT */
4041 rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
4042 rc = smk_bu_note("IPv6 delivery", skp, ssp->smk_in,
4043 MAY_WRITE, rc);
4044 #endif /* SMACK_IPV6_SECMARK_LABELING */
4045 #ifdef SMACK_IPV6_PORT_LABELING
4046 rc = smk_ipv6_port_check(sk, &sadd, SMK_RECEIVING);
4047 #endif /* SMACK_IPV6_PORT_LABELING */
4048 break;
4049 #endif /* CONFIG_IPV6 */
4050 }
4051
4052 return rc;
4053 }
4054
4055 /**
4056 * smack_socket_getpeersec_stream - pull in packet label
4057 * @sock: the socket
4058 * @optval: user's destination
4059 * @optlen: size thereof
4060 * @len: max thereof
4061 *
4062 * returns zero on success, an error code otherwise
4063 */
smack_socket_getpeersec_stream(struct socket * sock,char __user * optval,int __user * optlen,unsigned len)4064 static int smack_socket_getpeersec_stream(struct socket *sock,
4065 char __user *optval,
4066 int __user *optlen, unsigned len)
4067 {
4068 struct socket_smack *ssp;
4069 char *rcp = "";
4070 int slen = 1;
4071 int rc = 0;
4072
4073 ssp = sock->sk->sk_security;
4074 if (ssp->smk_packet != NULL) {
4075 rcp = ssp->smk_packet->smk_known;
4076 slen = strlen(rcp) + 1;
4077 }
4078
4079 if (slen > len)
4080 rc = -ERANGE;
4081 else if (copy_to_user(optval, rcp, slen) != 0)
4082 rc = -EFAULT;
4083
4084 if (put_user(slen, optlen) != 0)
4085 rc = -EFAULT;
4086
4087 return rc;
4088 }
4089
4090
4091 /**
4092 * smack_socket_getpeersec_dgram - pull in packet label
4093 * @sock: the peer socket
4094 * @skb: packet data
4095 * @secid: pointer to where to put the secid of the packet
4096 *
4097 * Sets the netlabel socket state on sk from parent
4098 */
smack_socket_getpeersec_dgram(struct socket * sock,struct sk_buff * skb,u32 * secid)4099 static int smack_socket_getpeersec_dgram(struct socket *sock,
4100 struct sk_buff *skb, u32 *secid)
4101
4102 {
4103 struct netlbl_lsm_secattr secattr;
4104 struct socket_smack *ssp = NULL;
4105 struct smack_known *skp;
4106 int family = PF_UNSPEC;
4107 u32 s = 0; /* 0 is the invalid secid */
4108 int rc;
4109
4110 if (skb != NULL) {
4111 if (skb->protocol == htons(ETH_P_IP))
4112 family = PF_INET;
4113 #if IS_ENABLED(CONFIG_IPV6)
4114 else if (skb->protocol == htons(ETH_P_IPV6))
4115 family = PF_INET6;
4116 #endif /* CONFIG_IPV6 */
4117 }
4118 if (family == PF_UNSPEC && sock != NULL)
4119 family = sock->sk->sk_family;
4120
4121 switch (family) {
4122 case PF_UNIX:
4123 ssp = sock->sk->sk_security;
4124 s = ssp->smk_out->smk_secid;
4125 break;
4126 case PF_INET:
4127 #ifdef CONFIG_SECURITY_SMACK_NETFILTER
4128 s = skb->secmark;
4129 if (s != 0)
4130 break;
4131 #endif
4132 /*
4133 * Translate what netlabel gave us.
4134 */
4135 if (sock != NULL && sock->sk != NULL)
4136 ssp = sock->sk->sk_security;
4137 netlbl_secattr_init(&secattr);
4138 rc = netlbl_skbuff_getattr(skb, family, &secattr);
4139 if (rc == 0) {
4140 skp = smack_from_secattr(&secattr, ssp);
4141 s = skp->smk_secid;
4142 }
4143 netlbl_secattr_destroy(&secattr);
4144 break;
4145 case PF_INET6:
4146 #ifdef SMACK_IPV6_SECMARK_LABELING
4147 s = skb->secmark;
4148 #endif
4149 break;
4150 }
4151 *secid = s;
4152 if (s == 0)
4153 return -EINVAL;
4154 return 0;
4155 }
4156
4157 /**
4158 * smack_sock_graft - Initialize a newly created socket with an existing sock
4159 * @sk: child sock
4160 * @parent: parent socket
4161 *
4162 * Set the smk_{in,out} state of an existing sock based on the process that
4163 * is creating the new socket.
4164 */
smack_sock_graft(struct sock * sk,struct socket * parent)4165 static void smack_sock_graft(struct sock *sk, struct socket *parent)
4166 {
4167 struct socket_smack *ssp;
4168 struct smack_known *skp = smk_of_current();
4169
4170 if (sk == NULL ||
4171 (sk->sk_family != PF_INET && sk->sk_family != PF_INET6))
4172 return;
4173
4174 ssp = sk->sk_security;
4175 ssp->smk_in = skp;
4176 ssp->smk_out = skp;
4177 /* cssp->smk_packet is already set in smack_inet_csk_clone() */
4178 }
4179
4180 /**
4181 * smack_inet_conn_request - Smack access check on connect
4182 * @sk: socket involved
4183 * @skb: packet
4184 * @req: unused
4185 *
4186 * Returns 0 if a task with the packet label could write to
4187 * the socket, otherwise an error code
4188 */
smack_inet_conn_request(struct sock * sk,struct sk_buff * skb,struct request_sock * req)4189 static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4190 struct request_sock *req)
4191 {
4192 u16 family = sk->sk_family;
4193 struct smack_known *skp;
4194 struct socket_smack *ssp = sk->sk_security;
4195 struct netlbl_lsm_secattr secattr;
4196 struct sockaddr_in addr;
4197 struct iphdr *hdr;
4198 struct smack_known *hskp;
4199 int rc;
4200 struct smk_audit_info ad;
4201 #ifdef CONFIG_AUDIT
4202 struct lsm_network_audit net;
4203 #endif
4204
4205 #if IS_ENABLED(CONFIG_IPV6)
4206 if (family == PF_INET6) {
4207 /*
4208 * Handle mapped IPv4 packets arriving
4209 * via IPv6 sockets. Don't set up netlabel
4210 * processing on IPv6.
4211 */
4212 if (skb->protocol == htons(ETH_P_IP))
4213 family = PF_INET;
4214 else
4215 return 0;
4216 }
4217 #endif /* CONFIG_IPV6 */
4218
4219 #ifdef CONFIG_SECURITY_SMACK_NETFILTER
4220 /*
4221 * If there is a secmark use it rather than the CIPSO label.
4222 * If there is no secmark fall back to CIPSO.
4223 * The secmark is assumed to reflect policy better.
4224 */
4225 if (skb && skb->secmark != 0) {
4226 skp = smack_from_secid(skb->secmark);
4227 goto access_check;
4228 }
4229 #endif /* CONFIG_SECURITY_SMACK_NETFILTER */
4230
4231 netlbl_secattr_init(&secattr);
4232 rc = netlbl_skbuff_getattr(skb, family, &secattr);
4233 if (rc == 0)
4234 skp = smack_from_secattr(&secattr, ssp);
4235 else
4236 skp = &smack_known_huh;
4237 netlbl_secattr_destroy(&secattr);
4238
4239 #ifdef CONFIG_SECURITY_SMACK_NETFILTER
4240 access_check:
4241 #endif
4242
4243 #ifdef CONFIG_AUDIT
4244 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
4245 ad.a.u.net->family = family;
4246 ad.a.u.net->netif = skb->skb_iif;
4247 ipv4_skb_to_auditdata(skb, &ad.a, NULL);
4248 #endif
4249 /*
4250 * Receiving a packet requires that the other end be able to write
4251 * here. Read access is not required.
4252 */
4253 rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad);
4254 rc = smk_bu_note("IPv4 connect", skp, ssp->smk_in, MAY_WRITE, rc);
4255 if (rc != 0)
4256 return rc;
4257
4258 /*
4259 * Save the peer's label in the request_sock so we can later setup
4260 * smk_packet in the child socket so that SO_PEERCRED can report it.
4261 */
4262 req->peer_secid = skp->smk_secid;
4263
4264 /*
4265 * We need to decide if we want to label the incoming connection here
4266 * if we do we only need to label the request_sock and the stack will
4267 * propagate the wire-label to the sock when it is created.
4268 */
4269 hdr = ip_hdr(skb);
4270 addr.sin_addr.s_addr = hdr->saddr;
4271 rcu_read_lock();
4272 hskp = smack_ipv4host_label(&addr);
4273 rcu_read_unlock();
4274
4275 if (hskp == NULL)
4276 rc = netlbl_req_setattr(req, &skp->smk_netlabel);
4277 else
4278 netlbl_req_delattr(req);
4279
4280 return rc;
4281 }
4282
4283 /**
4284 * smack_inet_csk_clone - Copy the connection information to the new socket
4285 * @sk: the new socket
4286 * @req: the connection's request_sock
4287 *
4288 * Transfer the connection's peer label to the newly created socket.
4289 */
smack_inet_csk_clone(struct sock * sk,const struct request_sock * req)4290 static void smack_inet_csk_clone(struct sock *sk,
4291 const struct request_sock *req)
4292 {
4293 struct socket_smack *ssp = sk->sk_security;
4294 struct smack_known *skp;
4295
4296 if (req->peer_secid != 0) {
4297 skp = smack_from_secid(req->peer_secid);
4298 ssp->smk_packet = skp;
4299 } else
4300 ssp->smk_packet = NULL;
4301 }
4302
4303 /*
4304 * Key management security hooks
4305 *
4306 * Casey has not tested key support very heavily.
4307 * The permission check is most likely too restrictive.
4308 * If you care about keys please have a look.
4309 */
4310 #ifdef CONFIG_KEYS
4311
4312 /**
4313 * smack_key_alloc - Set the key security blob
4314 * @key: object
4315 * @cred: the credentials to use
4316 * @flags: unused
4317 *
4318 * No allocation required
4319 *
4320 * Returns 0
4321 */
smack_key_alloc(struct key * key,const struct cred * cred,unsigned long flags)4322 static int smack_key_alloc(struct key *key, const struct cred *cred,
4323 unsigned long flags)
4324 {
4325 struct smack_known *skp = smk_of_task(cred->security);
4326
4327 key->security = skp;
4328 return 0;
4329 }
4330
4331 /**
4332 * smack_key_free - Clear the key security blob
4333 * @key: the object
4334 *
4335 * Clear the blob pointer
4336 */
smack_key_free(struct key * key)4337 static void smack_key_free(struct key *key)
4338 {
4339 key->security = NULL;
4340 }
4341
4342 /**
4343 * smack_key_permission - Smack access on a key
4344 * @key_ref: gets to the object
4345 * @cred: the credentials to use
4346 * @perm: requested key permissions
4347 *
4348 * Return 0 if the task has read and write to the object,
4349 * an error code otherwise
4350 */
smack_key_permission(key_ref_t key_ref,const struct cred * cred,unsigned perm)4351 static int smack_key_permission(key_ref_t key_ref,
4352 const struct cred *cred, unsigned perm)
4353 {
4354 struct key *keyp;
4355 struct smk_audit_info ad;
4356 struct smack_known *tkp = smk_of_task(cred->security);
4357 int request = 0;
4358 int rc;
4359
4360 keyp = key_ref_to_ptr(key_ref);
4361 if (keyp == NULL)
4362 return -EINVAL;
4363 /*
4364 * If the key hasn't been initialized give it access so that
4365 * it may do so.
4366 */
4367 if (keyp->security == NULL)
4368 return 0;
4369 /*
4370 * This should not occur
4371 */
4372 if (tkp == NULL)
4373 return -EACCES;
4374 #ifdef CONFIG_AUDIT
4375 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY);
4376 ad.a.u.key_struct.key = keyp->serial;
4377 ad.a.u.key_struct.key_desc = keyp->description;
4378 #endif
4379 if (perm & KEY_NEED_READ)
4380 request = MAY_READ;
4381 if (perm & (KEY_NEED_WRITE | KEY_NEED_LINK | KEY_NEED_SETATTR))
4382 request = MAY_WRITE;
4383 rc = smk_access(tkp, keyp->security, request, &ad);
4384 rc = smk_bu_note("key access", tkp, keyp->security, request, rc);
4385 return rc;
4386 }
4387
4388 /*
4389 * smack_key_getsecurity - Smack label tagging the key
4390 * @key points to the key to be queried
4391 * @_buffer points to a pointer that should be set to point to the
4392 * resulting string (if no label or an error occurs).
4393 * Return the length of the string (including terminating NUL) or -ve if
4394 * an error.
4395 * May also return 0 (and a NULL buffer pointer) if there is no label.
4396 */
smack_key_getsecurity(struct key * key,char ** _buffer)4397 static int smack_key_getsecurity(struct key *key, char **_buffer)
4398 {
4399 struct smack_known *skp = key->security;
4400 size_t length;
4401 char *copy;
4402
4403 if (key->security == NULL) {
4404 *_buffer = NULL;
4405 return 0;
4406 }
4407
4408 copy = kstrdup(skp->smk_known, GFP_KERNEL);
4409 if (copy == NULL)
4410 return -ENOMEM;
4411 length = strlen(copy) + 1;
4412
4413 *_buffer = copy;
4414 return length;
4415 }
4416
4417 #endif /* CONFIG_KEYS */
4418
4419 /*
4420 * Smack Audit hooks
4421 *
4422 * Audit requires a unique representation of each Smack specific
4423 * rule. This unique representation is used to distinguish the
4424 * object to be audited from remaining kernel objects and also
4425 * works as a glue between the audit hooks.
4426 *
4427 * Since repository entries are added but never deleted, we'll use
4428 * the smack_known label address related to the given audit rule as
4429 * the needed unique representation. This also better fits the smack
4430 * model where nearly everything is a label.
4431 */
4432 #ifdef CONFIG_AUDIT
4433
4434 /**
4435 * smack_audit_rule_init - Initialize a smack audit rule
4436 * @field: audit rule fields given from user-space (audit.h)
4437 * @op: required testing operator (=, !=, >, <, ...)
4438 * @rulestr: smack label to be audited
4439 * @vrule: pointer to save our own audit rule representation
4440 *
4441 * Prepare to audit cases where (@field @op @rulestr) is true.
4442 * The label to be audited is created if necessay.
4443 */
smack_audit_rule_init(u32 field,u32 op,char * rulestr,void ** vrule)4444 static int smack_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
4445 {
4446 struct smack_known *skp;
4447 char **rule = (char **)vrule;
4448 *rule = NULL;
4449
4450 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
4451 return -EINVAL;
4452
4453 if (op != Audit_equal && op != Audit_not_equal)
4454 return -EINVAL;
4455
4456 skp = smk_import_entry(rulestr, 0);
4457 if (IS_ERR(skp))
4458 return PTR_ERR(skp);
4459
4460 *rule = skp->smk_known;
4461
4462 return 0;
4463 }
4464
4465 /**
4466 * smack_audit_rule_known - Distinguish Smack audit rules
4467 * @krule: rule of interest, in Audit kernel representation format
4468 *
4469 * This is used to filter Smack rules from remaining Audit ones.
4470 * If it's proved that this rule belongs to us, the
4471 * audit_rule_match hook will be called to do the final judgement.
4472 */
smack_audit_rule_known(struct audit_krule * krule)4473 static int smack_audit_rule_known(struct audit_krule *krule)
4474 {
4475 struct audit_field *f;
4476 int i;
4477
4478 for (i = 0; i < krule->field_count; i++) {
4479 f = &krule->fields[i];
4480
4481 if (f->type == AUDIT_SUBJ_USER || f->type == AUDIT_OBJ_USER)
4482 return 1;
4483 }
4484
4485 return 0;
4486 }
4487
4488 /**
4489 * smack_audit_rule_match - Audit given object ?
4490 * @secid: security id for identifying the object to test
4491 * @field: audit rule flags given from user-space
4492 * @op: required testing operator
4493 * @vrule: smack internal rule presentation
4494 * @actx: audit context associated with the check
4495 *
4496 * The core Audit hook. It's used to take the decision of
4497 * whether to audit or not to audit a given object.
4498 */
smack_audit_rule_match(u32 secid,u32 field,u32 op,void * vrule,struct audit_context * actx)4499 static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule,
4500 struct audit_context *actx)
4501 {
4502 struct smack_known *skp;
4503 char *rule = vrule;
4504
4505 if (unlikely(!rule)) {
4506 WARN_ONCE(1, "Smack: missing rule\n");
4507 return -ENOENT;
4508 }
4509
4510 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
4511 return 0;
4512
4513 skp = smack_from_secid(secid);
4514
4515 /*
4516 * No need to do string comparisons. If a match occurs,
4517 * both pointers will point to the same smack_known
4518 * label.
4519 */
4520 if (op == Audit_equal)
4521 return (rule == skp->smk_known);
4522 if (op == Audit_not_equal)
4523 return (rule != skp->smk_known);
4524
4525 return 0;
4526 }
4527
4528 /*
4529 * There is no need for a smack_audit_rule_free hook.
4530 * No memory was allocated.
4531 */
4532
4533 #endif /* CONFIG_AUDIT */
4534
4535 /**
4536 * smack_ismaclabel - check if xattr @name references a smack MAC label
4537 * @name: Full xattr name to check.
4538 */
smack_ismaclabel(const char * name)4539 static int smack_ismaclabel(const char *name)
4540 {
4541 return (strcmp(name, XATTR_SMACK_SUFFIX) == 0);
4542 }
4543
4544
4545 /**
4546 * smack_secid_to_secctx - return the smack label for a secid
4547 * @secid: incoming integer
4548 * @secdata: destination
4549 * @seclen: how long it is
4550 *
4551 * Exists for networking code.
4552 */
smack_secid_to_secctx(u32 secid,char ** secdata,u32 * seclen)4553 static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
4554 {
4555 struct smack_known *skp = smack_from_secid(secid);
4556
4557 if (secdata)
4558 *secdata = skp->smk_known;
4559 *seclen = strlen(skp->smk_known);
4560 return 0;
4561 }
4562
4563 /**
4564 * smack_secctx_to_secid - return the secid for a smack label
4565 * @secdata: smack label
4566 * @seclen: how long result is
4567 * @secid: outgoing integer
4568 *
4569 * Exists for audit and networking code.
4570 */
smack_secctx_to_secid(const char * secdata,u32 seclen,u32 * secid)4571 static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
4572 {
4573 struct smack_known *skp = smk_find_entry(secdata);
4574
4575 if (skp)
4576 *secid = skp->smk_secid;
4577 else
4578 *secid = 0;
4579 return 0;
4580 }
4581
4582 /*
4583 * There used to be a smack_release_secctx hook
4584 * that did nothing back when hooks were in a vector.
4585 * Now that there's a list such a hook adds cost.
4586 */
4587
smack_inode_notifysecctx(struct inode * inode,void * ctx,u32 ctxlen)4588 static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
4589 {
4590 return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx, ctxlen, 0);
4591 }
4592
smack_inode_setsecctx(struct dentry * dentry,void * ctx,u32 ctxlen)4593 static int smack_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
4594 {
4595 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SMACK, ctx, ctxlen, 0);
4596 }
4597
smack_inode_getsecctx(struct inode * inode,void ** ctx,u32 * ctxlen)4598 static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
4599 {
4600 int len = 0;
4601 len = smack_inode_getsecurity(inode, XATTR_SMACK_SUFFIX, ctx, true);
4602
4603 if (len < 0)
4604 return len;
4605 *ctxlen = len;
4606 return 0;
4607 }
4608
4609 static struct security_hook_list smack_hooks[] = {
4610 LSM_HOOK_INIT(ptrace_access_check, smack_ptrace_access_check),
4611 LSM_HOOK_INIT(ptrace_traceme, smack_ptrace_traceme),
4612 LSM_HOOK_INIT(syslog, smack_syslog),
4613
4614 LSM_HOOK_INIT(sb_alloc_security, smack_sb_alloc_security),
4615 LSM_HOOK_INIT(sb_free_security, smack_sb_free_security),
4616 LSM_HOOK_INIT(sb_copy_data, smack_sb_copy_data),
4617 LSM_HOOK_INIT(sb_kern_mount, smack_sb_kern_mount),
4618 LSM_HOOK_INIT(sb_statfs, smack_sb_statfs),
4619 LSM_HOOK_INIT(sb_set_mnt_opts, smack_set_mnt_opts),
4620 LSM_HOOK_INIT(sb_parse_opts_str, smack_parse_opts_str),
4621
4622 LSM_HOOK_INIT(bprm_set_creds, smack_bprm_set_creds),
4623 LSM_HOOK_INIT(bprm_committing_creds, smack_bprm_committing_creds),
4624 LSM_HOOK_INIT(bprm_secureexec, smack_bprm_secureexec),
4625
4626 LSM_HOOK_INIT(inode_alloc_security, smack_inode_alloc_security),
4627 LSM_HOOK_INIT(inode_free_security, smack_inode_free_security),
4628 LSM_HOOK_INIT(inode_init_security, smack_inode_init_security),
4629 LSM_HOOK_INIT(inode_link, smack_inode_link),
4630 LSM_HOOK_INIT(inode_unlink, smack_inode_unlink),
4631 LSM_HOOK_INIT(inode_rmdir, smack_inode_rmdir),
4632 LSM_HOOK_INIT(inode_rename, smack_inode_rename),
4633 LSM_HOOK_INIT(inode_permission, smack_inode_permission),
4634 LSM_HOOK_INIT(inode_setattr, smack_inode_setattr),
4635 LSM_HOOK_INIT(inode_getattr, smack_inode_getattr),
4636 LSM_HOOK_INIT(inode_setxattr, smack_inode_setxattr),
4637 LSM_HOOK_INIT(inode_post_setxattr, smack_inode_post_setxattr),
4638 LSM_HOOK_INIT(inode_getxattr, smack_inode_getxattr),
4639 LSM_HOOK_INIT(inode_removexattr, smack_inode_removexattr),
4640 LSM_HOOK_INIT(inode_getsecurity, smack_inode_getsecurity),
4641 LSM_HOOK_INIT(inode_setsecurity, smack_inode_setsecurity),
4642 LSM_HOOK_INIT(inode_listsecurity, smack_inode_listsecurity),
4643 LSM_HOOK_INIT(inode_getsecid, smack_inode_getsecid),
4644
4645 LSM_HOOK_INIT(file_alloc_security, smack_file_alloc_security),
4646 LSM_HOOK_INIT(file_free_security, smack_file_free_security),
4647 LSM_HOOK_INIT(file_ioctl, smack_file_ioctl),
4648 LSM_HOOK_INIT(file_lock, smack_file_lock),
4649 LSM_HOOK_INIT(file_fcntl, smack_file_fcntl),
4650 LSM_HOOK_INIT(mmap_file, smack_mmap_file),
4651 LSM_HOOK_INIT(mmap_addr, cap_mmap_addr),
4652 LSM_HOOK_INIT(file_set_fowner, smack_file_set_fowner),
4653 LSM_HOOK_INIT(file_send_sigiotask, smack_file_send_sigiotask),
4654 LSM_HOOK_INIT(file_receive, smack_file_receive),
4655
4656 LSM_HOOK_INIT(file_open, smack_file_open),
4657
4658 LSM_HOOK_INIT(cred_alloc_blank, smack_cred_alloc_blank),
4659 LSM_HOOK_INIT(cred_free, smack_cred_free),
4660 LSM_HOOK_INIT(cred_prepare, smack_cred_prepare),
4661 LSM_HOOK_INIT(cred_transfer, smack_cred_transfer),
4662 LSM_HOOK_INIT(kernel_act_as, smack_kernel_act_as),
4663 LSM_HOOK_INIT(kernel_create_files_as, smack_kernel_create_files_as),
4664 LSM_HOOK_INIT(task_setpgid, smack_task_setpgid),
4665 LSM_HOOK_INIT(task_getpgid, smack_task_getpgid),
4666 LSM_HOOK_INIT(task_getsid, smack_task_getsid),
4667 LSM_HOOK_INIT(task_getsecid, smack_task_getsecid),
4668 LSM_HOOK_INIT(task_setnice, smack_task_setnice),
4669 LSM_HOOK_INIT(task_setioprio, smack_task_setioprio),
4670 LSM_HOOK_INIT(task_getioprio, smack_task_getioprio),
4671 LSM_HOOK_INIT(task_setscheduler, smack_task_setscheduler),
4672 LSM_HOOK_INIT(task_getscheduler, smack_task_getscheduler),
4673 LSM_HOOK_INIT(task_movememory, smack_task_movememory),
4674 LSM_HOOK_INIT(task_kill, smack_task_kill),
4675 LSM_HOOK_INIT(task_wait, smack_task_wait),
4676 LSM_HOOK_INIT(task_to_inode, smack_task_to_inode),
4677
4678 LSM_HOOK_INIT(ipc_permission, smack_ipc_permission),
4679 LSM_HOOK_INIT(ipc_getsecid, smack_ipc_getsecid),
4680
4681 LSM_HOOK_INIT(msg_msg_alloc_security, smack_msg_msg_alloc_security),
4682 LSM_HOOK_INIT(msg_msg_free_security, smack_msg_msg_free_security),
4683
4684 LSM_HOOK_INIT(msg_queue_alloc_security, smack_msg_queue_alloc_security),
4685 LSM_HOOK_INIT(msg_queue_free_security, smack_msg_queue_free_security),
4686 LSM_HOOK_INIT(msg_queue_associate, smack_msg_queue_associate),
4687 LSM_HOOK_INIT(msg_queue_msgctl, smack_msg_queue_msgctl),
4688 LSM_HOOK_INIT(msg_queue_msgsnd, smack_msg_queue_msgsnd),
4689 LSM_HOOK_INIT(msg_queue_msgrcv, smack_msg_queue_msgrcv),
4690
4691 LSM_HOOK_INIT(shm_alloc_security, smack_shm_alloc_security),
4692 LSM_HOOK_INIT(shm_free_security, smack_shm_free_security),
4693 LSM_HOOK_INIT(shm_associate, smack_shm_associate),
4694 LSM_HOOK_INIT(shm_shmctl, smack_shm_shmctl),
4695 LSM_HOOK_INIT(shm_shmat, smack_shm_shmat),
4696
4697 LSM_HOOK_INIT(sem_alloc_security, smack_sem_alloc_security),
4698 LSM_HOOK_INIT(sem_free_security, smack_sem_free_security),
4699 LSM_HOOK_INIT(sem_associate, smack_sem_associate),
4700 LSM_HOOK_INIT(sem_semctl, smack_sem_semctl),
4701 LSM_HOOK_INIT(sem_semop, smack_sem_semop),
4702
4703 LSM_HOOK_INIT(d_instantiate, smack_d_instantiate),
4704
4705 LSM_HOOK_INIT(getprocattr, smack_getprocattr),
4706 LSM_HOOK_INIT(setprocattr, smack_setprocattr),
4707
4708 LSM_HOOK_INIT(unix_stream_connect, smack_unix_stream_connect),
4709 LSM_HOOK_INIT(unix_may_send, smack_unix_may_send),
4710
4711 LSM_HOOK_INIT(socket_post_create, smack_socket_post_create),
4712 #ifdef SMACK_IPV6_PORT_LABELING
4713 LSM_HOOK_INIT(socket_bind, smack_socket_bind),
4714 #endif
4715 LSM_HOOK_INIT(socket_connect, smack_socket_connect),
4716 LSM_HOOK_INIT(socket_sendmsg, smack_socket_sendmsg),
4717 LSM_HOOK_INIT(socket_sock_rcv_skb, smack_socket_sock_rcv_skb),
4718 LSM_HOOK_INIT(socket_getpeersec_stream, smack_socket_getpeersec_stream),
4719 LSM_HOOK_INIT(socket_getpeersec_dgram, smack_socket_getpeersec_dgram),
4720 LSM_HOOK_INIT(sk_alloc_security, smack_sk_alloc_security),
4721 LSM_HOOK_INIT(sk_free_security, smack_sk_free_security),
4722 LSM_HOOK_INIT(sock_graft, smack_sock_graft),
4723 LSM_HOOK_INIT(inet_conn_request, smack_inet_conn_request),
4724 LSM_HOOK_INIT(inet_csk_clone, smack_inet_csk_clone),
4725
4726 /* key management security hooks */
4727 #ifdef CONFIG_KEYS
4728 LSM_HOOK_INIT(key_alloc, smack_key_alloc),
4729 LSM_HOOK_INIT(key_free, smack_key_free),
4730 LSM_HOOK_INIT(key_permission, smack_key_permission),
4731 LSM_HOOK_INIT(key_getsecurity, smack_key_getsecurity),
4732 #endif /* CONFIG_KEYS */
4733
4734 /* Audit hooks */
4735 #ifdef CONFIG_AUDIT
4736 LSM_HOOK_INIT(audit_rule_init, smack_audit_rule_init),
4737 LSM_HOOK_INIT(audit_rule_known, smack_audit_rule_known),
4738 LSM_HOOK_INIT(audit_rule_match, smack_audit_rule_match),
4739 #endif /* CONFIG_AUDIT */
4740
4741 LSM_HOOK_INIT(ismaclabel, smack_ismaclabel),
4742 LSM_HOOK_INIT(secid_to_secctx, smack_secid_to_secctx),
4743 LSM_HOOK_INIT(secctx_to_secid, smack_secctx_to_secid),
4744 LSM_HOOK_INIT(inode_notifysecctx, smack_inode_notifysecctx),
4745 LSM_HOOK_INIT(inode_setsecctx, smack_inode_setsecctx),
4746 LSM_HOOK_INIT(inode_getsecctx, smack_inode_getsecctx),
4747 };
4748
4749
init_smack_known_list(void)4750 static __init void init_smack_known_list(void)
4751 {
4752 /*
4753 * Initialize rule list locks
4754 */
4755 mutex_init(&smack_known_huh.smk_rules_lock);
4756 mutex_init(&smack_known_hat.smk_rules_lock);
4757 mutex_init(&smack_known_floor.smk_rules_lock);
4758 mutex_init(&smack_known_star.smk_rules_lock);
4759 mutex_init(&smack_known_invalid.smk_rules_lock);
4760 mutex_init(&smack_known_web.smk_rules_lock);
4761 /*
4762 * Initialize rule lists
4763 */
4764 INIT_LIST_HEAD(&smack_known_huh.smk_rules);
4765 INIT_LIST_HEAD(&smack_known_hat.smk_rules);
4766 INIT_LIST_HEAD(&smack_known_star.smk_rules);
4767 INIT_LIST_HEAD(&smack_known_floor.smk_rules);
4768 INIT_LIST_HEAD(&smack_known_invalid.smk_rules);
4769 INIT_LIST_HEAD(&smack_known_web.smk_rules);
4770 /*
4771 * Create the known labels list
4772 */
4773 smk_insert_entry(&smack_known_huh);
4774 smk_insert_entry(&smack_known_hat);
4775 smk_insert_entry(&smack_known_star);
4776 smk_insert_entry(&smack_known_floor);
4777 smk_insert_entry(&smack_known_invalid);
4778 smk_insert_entry(&smack_known_web);
4779 }
4780
4781 /**
4782 * smack_init - initialize the smack system
4783 *
4784 * Returns 0
4785 */
smack_init(void)4786 static __init int smack_init(void)
4787 {
4788 struct cred *cred;
4789 struct task_smack *tsp;
4790
4791 if (!security_module_enable("smack"))
4792 return 0;
4793
4794 smack_inode_cache = KMEM_CACHE(inode_smack, 0);
4795 if (!smack_inode_cache)
4796 return -ENOMEM;
4797
4798 tsp = new_task_smack(&smack_known_floor, &smack_known_floor,
4799 GFP_KERNEL);
4800 if (tsp == NULL) {
4801 kmem_cache_destroy(smack_inode_cache);
4802 return -ENOMEM;
4803 }
4804
4805 smack_enabled = 1;
4806
4807 pr_info("Smack: Initializing.\n");
4808 #ifdef CONFIG_SECURITY_SMACK_NETFILTER
4809 pr_info("Smack: Netfilter enabled.\n");
4810 #endif
4811 #ifdef SMACK_IPV6_PORT_LABELING
4812 pr_info("Smack: IPv6 port labeling enabled.\n");
4813 #endif
4814 #ifdef SMACK_IPV6_SECMARK_LABELING
4815 pr_info("Smack: IPv6 Netfilter enabled.\n");
4816 #endif
4817
4818 /*
4819 * Set the security state for the initial task.
4820 */
4821 cred = (struct cred *) current->cred;
4822 cred->security = tsp;
4823
4824 /* initialize the smack_known_list */
4825 init_smack_known_list();
4826
4827 /*
4828 * Register with LSM
4829 */
4830 security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks));
4831
4832 return 0;
4833 }
4834
4835 /*
4836 * Smack requires early initialization in order to label
4837 * all processes and objects when they are created.
4838 */
4839 security_initcall(smack_init);
4840