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