2 * Simplified MAC Kernel (smack) security module
4 * This file contains the smack hook function implementations.
7 * Casey Schaufler <casey@schaufler-ca.com>
8 * Jarkko Sakkinen <jarkko.sakkinen@intel.com>
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.
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.
21 #include <linux/xattr.h>
22 #include <linux/pagemap.h>
23 #include <linux/mount.h>
24 #include <linux/stat.h>
26 #include <asm/ioctls.h>
28 #include <linux/tcp.h>
29 #include <linux/udp.h>
30 #include <linux/slab.h>
31 #include <linux/mutex.h>
32 #include <linux/pipe_fs_i.h>
33 #include <net/netlabel.h>
34 #include <net/cipso_ipv4.h>
35 #include <linux/audit.h>
36 #include <linux/magic.h>
37 #include <linux/dcache.h>
38 #include <linux/personality.h>
39 #include <linux/msg.h>
40 #include <linux/shm.h>
41 #include <linux/binfmts.h>
44 #define task_security(task) (task_cred_xxx((task), security))
46 #define TRANS_TRUE "TRUE"
47 #define TRANS_TRUE_SIZE 4
50 * smk_fetch - Fetch the smack label from a file.
51 * @ip: a pointer to the inode
52 * @dp: a pointer to the dentry
54 * Returns a pointer to the master list entry for the Smack label
55 * or NULL if there was no label to fetch.
57 static char *smk_fetch(const char *name, struct inode *ip, struct dentry *dp)
60 char in[SMK_LABELLEN];
62 if (ip->i_op->getxattr == NULL)
65 rc = ip->i_op->getxattr(dp, name, in, SMK_LABELLEN);
69 return smk_import(in, rc);
73 * new_inode_smack - allocate an inode security blob
74 * @smack: a pointer to the Smack label to use in the blob
76 * Returns the new blob or NULL if there's no memory available
78 struct inode_smack *new_inode_smack(char *smack)
80 struct inode_smack *isp;
82 isp = kzalloc(sizeof(struct inode_smack), GFP_KERNEL);
86 isp->smk_inode = smack;
88 mutex_init(&isp->smk_lock);
94 * new_task_smack - allocate a task security blob
95 * @smack: a pointer to the Smack label to use in the blob
97 * Returns the new blob or NULL if there's no memory available
99 static struct task_smack *new_task_smack(char *task, char *forked, gfp_t gfp)
101 struct task_smack *tsp;
103 tsp = kzalloc(sizeof(struct task_smack), gfp);
107 tsp->smk_task = task;
108 tsp->smk_forked = forked;
109 INIT_LIST_HEAD(&tsp->smk_rules);
110 mutex_init(&tsp->smk_rules_lock);
116 * smk_copy_rules - copy a rule set
117 * @nhead - new rules header pointer
118 * @ohead - old rules header pointer
120 * Returns 0 on success, -ENOMEM on error
122 static int smk_copy_rules(struct list_head *nhead, struct list_head *ohead,
125 struct smack_rule *nrp;
126 struct smack_rule *orp;
129 INIT_LIST_HEAD(nhead);
131 list_for_each_entry_rcu(orp, ohead, list) {
132 nrp = kzalloc(sizeof(struct smack_rule), gfp);
138 list_add_rcu(&nrp->list, nhead);
145 * We he, that is fun!
149 * smack_ptrace_access_check - Smack approval on PTRACE_ATTACH
150 * @ctp: child task pointer
151 * @mode: ptrace attachment mode
153 * Returns 0 if access is OK, an error code otherwise
155 * Do the capability checks, and require read and write.
157 static int smack_ptrace_access_check(struct task_struct *ctp, unsigned int mode)
160 struct smk_audit_info ad;
163 rc = cap_ptrace_access_check(ctp, mode);
167 tsp = smk_of_task(task_security(ctp));
168 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
169 smk_ad_setfield_u_tsk(&ad, ctp);
171 rc = smk_curacc(tsp, MAY_READWRITE, &ad);
176 * smack_ptrace_traceme - Smack approval on PTRACE_TRACEME
177 * @ptp: parent task pointer
179 * Returns 0 if access is OK, an error code otherwise
181 * Do the capability checks, and require read and write.
183 static int smack_ptrace_traceme(struct task_struct *ptp)
186 struct smk_audit_info ad;
189 rc = cap_ptrace_traceme(ptp);
193 tsp = smk_of_task(task_security(ptp));
194 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
195 smk_ad_setfield_u_tsk(&ad, ptp);
197 rc = smk_curacc(tsp, MAY_READWRITE, &ad);
202 * smack_syslog - Smack approval on syslog
203 * @type: message type
205 * Require that the task has the floor label
207 * Returns 0 on success, error code otherwise.
209 static int smack_syslog(int typefrom_file)
212 char *sp = smk_of_current();
214 if (capable(CAP_MAC_OVERRIDE))
217 if (sp != smack_known_floor.smk_known)
229 * smack_sb_alloc_security - allocate a superblock blob
230 * @sb: the superblock getting the blob
232 * Returns 0 on success or -ENOMEM on error.
234 static int smack_sb_alloc_security(struct super_block *sb)
236 struct superblock_smack *sbsp;
238 sbsp = kzalloc(sizeof(struct superblock_smack), GFP_KERNEL);
243 sbsp->smk_root = smack_known_floor.smk_known;
244 sbsp->smk_default = smack_known_floor.smk_known;
245 sbsp->smk_floor = smack_known_floor.smk_known;
246 sbsp->smk_hat = smack_known_hat.smk_known;
247 sbsp->smk_initialized = 0;
248 spin_lock_init(&sbsp->smk_sblock);
250 sb->s_security = sbsp;
256 * smack_sb_free_security - free a superblock blob
257 * @sb: the superblock getting the blob
260 static void smack_sb_free_security(struct super_block *sb)
262 kfree(sb->s_security);
263 sb->s_security = NULL;
267 * smack_sb_copy_data - copy mount options data for processing
268 * @orig: where to start
269 * @smackopts: mount options string
271 * Returns 0 on success or -ENOMEM on error.
273 * Copy the Smack specific mount options out of the mount
276 static int smack_sb_copy_data(char *orig, char *smackopts)
278 char *cp, *commap, *otheropts, *dp;
280 otheropts = (char *)get_zeroed_page(GFP_KERNEL);
281 if (otheropts == NULL)
284 for (cp = orig, commap = orig; commap != NULL; cp = commap + 1) {
285 if (strstr(cp, SMK_FSDEFAULT) == cp)
287 else if (strstr(cp, SMK_FSFLOOR) == cp)
289 else if (strstr(cp, SMK_FSHAT) == cp)
291 else if (strstr(cp, SMK_FSROOT) == cp)
296 commap = strchr(cp, ',');
305 strcpy(orig, otheropts);
306 free_page((unsigned long)otheropts);
312 * smack_sb_kern_mount - Smack specific mount processing
313 * @sb: the file system superblock
314 * @flags: the mount flags
315 * @data: the smack mount options
317 * Returns 0 on success, an error code on failure
319 static int smack_sb_kern_mount(struct super_block *sb, int flags, void *data)
321 struct dentry *root = sb->s_root;
322 struct inode *inode = root->d_inode;
323 struct superblock_smack *sp = sb->s_security;
324 struct inode_smack *isp;
329 spin_lock(&sp->smk_sblock);
330 if (sp->smk_initialized != 0) {
331 spin_unlock(&sp->smk_sblock);
334 sp->smk_initialized = 1;
335 spin_unlock(&sp->smk_sblock);
337 for (op = data; op != NULL; op = commap) {
338 commap = strchr(op, ',');
342 if (strncmp(op, SMK_FSHAT, strlen(SMK_FSHAT)) == 0) {
343 op += strlen(SMK_FSHAT);
344 nsp = smk_import(op, 0);
347 } else if (strncmp(op, SMK_FSFLOOR, strlen(SMK_FSFLOOR)) == 0) {
348 op += strlen(SMK_FSFLOOR);
349 nsp = smk_import(op, 0);
352 } else if (strncmp(op, SMK_FSDEFAULT,
353 strlen(SMK_FSDEFAULT)) == 0) {
354 op += strlen(SMK_FSDEFAULT);
355 nsp = smk_import(op, 0);
357 sp->smk_default = nsp;
358 } else if (strncmp(op, SMK_FSROOT, strlen(SMK_FSROOT)) == 0) {
359 op += strlen(SMK_FSROOT);
360 nsp = smk_import(op, 0);
367 * Initialize the root inode.
369 isp = inode->i_security;
371 inode->i_security = new_inode_smack(sp->smk_root);
373 isp->smk_inode = sp->smk_root;
379 * smack_sb_statfs - Smack check on statfs
380 * @dentry: identifies the file system in question
382 * Returns 0 if current can read the floor of the filesystem,
383 * and error code otherwise
385 static int smack_sb_statfs(struct dentry *dentry)
387 struct superblock_smack *sbp = dentry->d_sb->s_security;
389 struct smk_audit_info ad;
391 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
392 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
394 rc = smk_curacc(sbp->smk_floor, MAY_READ, &ad);
399 * smack_sb_mount - Smack check for mounting
406 * Returns 0 if current can write the floor of the filesystem
407 * being mounted on, an error code otherwise.
409 static int smack_sb_mount(char *dev_name, struct path *path,
410 char *type, unsigned long flags, void *data)
412 struct superblock_smack *sbp = path->dentry->d_sb->s_security;
413 struct smk_audit_info ad;
415 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
416 smk_ad_setfield_u_fs_path(&ad, *path);
418 return smk_curacc(sbp->smk_floor, MAY_WRITE, &ad);
422 * smack_sb_umount - Smack check for unmounting
423 * @mnt: file system to unmount
426 * Returns 0 if current can write the floor of the filesystem
427 * being unmounted, an error code otherwise.
429 static int smack_sb_umount(struct vfsmount *mnt, int flags)
431 struct superblock_smack *sbp;
432 struct smk_audit_info ad;
435 path.dentry = mnt->mnt_root;
438 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
439 smk_ad_setfield_u_fs_path(&ad, path);
441 sbp = path.dentry->d_sb->s_security;
442 return smk_curacc(sbp->smk_floor, MAY_WRITE, &ad);
450 * smack_bprm_set_creds - set creds for exec
451 * @bprm: the exec information
453 * Returns 0 if it gets a blob, -ENOMEM otherwise
455 static int smack_bprm_set_creds(struct linux_binprm *bprm)
457 struct inode *inode = bprm->file->f_path.dentry->d_inode;
458 struct task_smack *bsp = bprm->cred->security;
459 struct inode_smack *isp;
462 rc = cap_bprm_set_creds(bprm);
466 if (bprm->cred_prepared)
469 isp = inode->i_security;
470 if (isp->smk_task == NULL || isp->smk_task == bsp->smk_task)
476 bsp->smk_task = isp->smk_task;
477 bprm->per_clear |= PER_CLEAR_ON_SETID;
483 * smack_bprm_committing_creds - Prepare to install the new credentials
486 * @bprm: binprm for exec
488 static void smack_bprm_committing_creds(struct linux_binprm *bprm)
490 struct task_smack *bsp = bprm->cred->security;
492 if (bsp->smk_task != bsp->smk_forked)
493 current->pdeath_signal = 0;
497 * smack_bprm_secureexec - Return the decision to use secureexec.
498 * @bprm: binprm for exec
500 * Returns 0 on success.
502 static int smack_bprm_secureexec(struct linux_binprm *bprm)
504 struct task_smack *tsp = current_security();
505 int ret = cap_bprm_secureexec(bprm);
507 if (!ret && (tsp->smk_task != tsp->smk_forked))
518 * smack_inode_alloc_security - allocate an inode blob
519 * @inode: the inode in need of a blob
521 * Returns 0 if it gets a blob, -ENOMEM otherwise
523 static int smack_inode_alloc_security(struct inode *inode)
525 inode->i_security = new_inode_smack(smk_of_current());
526 if (inode->i_security == NULL)
532 * smack_inode_free_security - free an inode blob
533 * @inode: the inode with a blob
535 * Clears the blob pointer in inode
537 static void smack_inode_free_security(struct inode *inode)
539 kfree(inode->i_security);
540 inode->i_security = NULL;
544 * smack_inode_init_security - copy out the smack from an inode
548 * @name: where to put the attribute name
549 * @value: where to put the attribute value
550 * @len: where to put the length of the attribute
552 * Returns 0 if it all works out, -ENOMEM if there's no memory
554 static int smack_inode_init_security(struct inode *inode, struct inode *dir,
555 const struct qstr *qstr, char **name,
556 void **value, size_t *len)
558 struct smack_known *skp;
559 char *csp = smk_of_current();
560 char *isp = smk_of_inode(inode);
561 char *dsp = smk_of_inode(dir);
565 *name = kstrdup(XATTR_SMACK_SUFFIX, GFP_KERNEL);
571 skp = smk_find_entry(csp);
573 may = smk_access_entry(csp, dsp, &skp->smk_rules);
577 * If the access rule allows transmutation and
578 * the directory requests transmutation then
579 * by all means transmute.
581 if (may > 0 && ((may & MAY_TRANSMUTE) != 0) &&
582 smk_inode_transmutable(dir))
585 *value = kstrdup(isp, GFP_KERNEL);
591 *len = strlen(isp) + 1;
597 * smack_inode_link - Smack check on link
598 * @old_dentry: the existing object
600 * @new_dentry: the new object
602 * Returns 0 if access is permitted, an error code otherwise
604 static int smack_inode_link(struct dentry *old_dentry, struct inode *dir,
605 struct dentry *new_dentry)
608 struct smk_audit_info ad;
611 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
612 smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
614 isp = smk_of_inode(old_dentry->d_inode);
615 rc = smk_curacc(isp, MAY_WRITE, &ad);
617 if (rc == 0 && new_dentry->d_inode != NULL) {
618 isp = smk_of_inode(new_dentry->d_inode);
619 smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
620 rc = smk_curacc(isp, MAY_WRITE, &ad);
627 * smack_inode_unlink - Smack check on inode deletion
628 * @dir: containing directory object
629 * @dentry: file to unlink
631 * Returns 0 if current can write the containing directory
632 * and the object, error code otherwise
634 static int smack_inode_unlink(struct inode *dir, struct dentry *dentry)
636 struct inode *ip = dentry->d_inode;
637 struct smk_audit_info ad;
640 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
641 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
644 * You need write access to the thing you're unlinking
646 rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad);
649 * You also need write access to the containing directory
651 smk_ad_setfield_u_fs_path_dentry(&ad, NULL);
652 smk_ad_setfield_u_fs_inode(&ad, dir);
653 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
659 * smack_inode_rmdir - Smack check on directory deletion
660 * @dir: containing directory object
661 * @dentry: directory to unlink
663 * Returns 0 if current can write the containing directory
664 * and the directory, error code otherwise
666 static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry)
668 struct smk_audit_info ad;
671 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
672 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
675 * You need write access to the thing you're removing
677 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
680 * You also need write access to the containing directory
682 smk_ad_setfield_u_fs_path_dentry(&ad, NULL);
683 smk_ad_setfield_u_fs_inode(&ad, dir);
684 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad);
691 * smack_inode_rename - Smack check on rename
692 * @old_inode: the old directory
693 * @old_dentry: unused
694 * @new_inode: the new directory
695 * @new_dentry: unused
697 * Read and write access is required on both the old and
700 * Returns 0 if access is permitted, an error code otherwise
702 static int smack_inode_rename(struct inode *old_inode,
703 struct dentry *old_dentry,
704 struct inode *new_inode,
705 struct dentry *new_dentry)
709 struct smk_audit_info ad;
711 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
712 smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry);
714 isp = smk_of_inode(old_dentry->d_inode);
715 rc = smk_curacc(isp, MAY_READWRITE, &ad);
717 if (rc == 0 && new_dentry->d_inode != NULL) {
718 isp = smk_of_inode(new_dentry->d_inode);
719 smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry);
720 rc = smk_curacc(isp, MAY_READWRITE, &ad);
726 * smack_inode_permission - Smack version of permission()
727 * @inode: the inode in question
728 * @mask: the access requested
730 * This is the important Smack hook.
732 * Returns 0 if access is permitted, -EACCES otherwise
734 static int smack_inode_permission(struct inode *inode, int mask)
736 struct smk_audit_info ad;
737 int no_block = mask & MAY_NOT_BLOCK;
739 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
741 * No permission to check. Existence test. Yup, it's there.
746 /* May be droppable after audit */
749 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE);
750 smk_ad_setfield_u_fs_inode(&ad, inode);
751 return smk_curacc(smk_of_inode(inode), mask, &ad);
755 * smack_inode_setattr - Smack check for setting attributes
756 * @dentry: the object
757 * @iattr: for the force flag
759 * Returns 0 if access is permitted, an error code otherwise
761 static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr)
763 struct smk_audit_info ad;
765 * Need to allow for clearing the setuid bit.
767 if (iattr->ia_valid & ATTR_FORCE)
769 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
770 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
772 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
776 * smack_inode_getattr - Smack check for getting attributes
778 * @dentry: the object
780 * Returns 0 if access is permitted, an error code otherwise
782 static int smack_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
784 struct smk_audit_info ad;
787 path.dentry = dentry;
790 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
791 smk_ad_setfield_u_fs_path(&ad, path);
792 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad);
796 * smack_inode_setxattr - Smack check for setting xattrs
797 * @dentry: the object
798 * @name: name of the attribute
803 * This protects the Smack attribute explicitly.
805 * Returns 0 if access is permitted, an error code otherwise
807 static int smack_inode_setxattr(struct dentry *dentry, const char *name,
808 const void *value, size_t size, int flags)
810 struct smk_audit_info ad;
813 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
814 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
815 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
816 strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
817 strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
818 if (!capable(CAP_MAC_ADMIN))
821 * check label validity here so import wont fail on
824 if (size == 0 || size >= SMK_LABELLEN ||
825 smk_import(value, size) == NULL)
827 } else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) {
828 if (!capable(CAP_MAC_ADMIN))
830 if (size != TRANS_TRUE_SIZE ||
831 strncmp(value, TRANS_TRUE, TRANS_TRUE_SIZE) != 0)
834 rc = cap_inode_setxattr(dentry, name, value, size, flags);
836 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
837 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
840 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
846 * smack_inode_post_setxattr - Apply the Smack update approved above
848 * @name: attribute name
849 * @value: attribute value
850 * @size: attribute size
853 * Set the pointer in the inode blob to the entry found
854 * in the master label list.
856 static void smack_inode_post_setxattr(struct dentry *dentry, const char *name,
857 const void *value, size_t size, int flags)
860 struct inode_smack *isp = dentry->d_inode->i_security;
862 if (strcmp(name, XATTR_NAME_SMACK) == 0) {
863 nsp = smk_import(value, size);
865 isp->smk_inode = nsp;
867 isp->smk_inode = smack_known_invalid.smk_known;
868 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0) {
869 nsp = smk_import(value, size);
873 isp->smk_task = smack_known_invalid.smk_known;
874 } else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) {
875 nsp = smk_import(value, size);
879 isp->smk_mmap = smack_known_invalid.smk_known;
880 } else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0)
881 isp->smk_flags |= SMK_INODE_TRANSMUTE;
887 * smack_inode_getxattr - Smack check on getxattr
888 * @dentry: the object
891 * Returns 0 if access is permitted, an error code otherwise
893 static int smack_inode_getxattr(struct dentry *dentry, const char *name)
895 struct smk_audit_info ad;
897 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
898 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
900 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad);
904 * smack_inode_removexattr - Smack check on removexattr
905 * @dentry: the object
906 * @name: name of the attribute
908 * Removing the Smack attribute requires CAP_MAC_ADMIN
910 * Returns 0 if access is permitted, an error code otherwise
912 static int smack_inode_removexattr(struct dentry *dentry, const char *name)
914 struct inode_smack *isp;
915 struct smk_audit_info ad;
918 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
919 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
920 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 ||
921 strcmp(name, XATTR_NAME_SMACKEXEC) == 0 ||
922 strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0 ||
923 strcmp(name, XATTR_NAME_SMACKMMAP)) {
924 if (!capable(CAP_MAC_ADMIN))
927 rc = cap_inode_removexattr(dentry, name);
929 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY);
930 smk_ad_setfield_u_fs_path_dentry(&ad, dentry);
932 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad);
935 isp = dentry->d_inode->i_security;
936 isp->smk_task = NULL;
937 isp->smk_mmap = NULL;
944 * smack_inode_getsecurity - get smack xattrs
946 * @name: attribute name
947 * @buffer: where to put the result
950 * Returns the size of the attribute or an error code
952 static int smack_inode_getsecurity(const struct inode *inode,
953 const char *name, void **buffer,
956 struct socket_smack *ssp;
958 struct super_block *sbp;
959 struct inode *ip = (struct inode *)inode;
964 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
965 isp = smk_of_inode(inode);
966 ilen = strlen(isp) + 1;
972 * The rest of the Smack xattrs are only on sockets.
975 if (sbp->s_magic != SOCKFS_MAGIC)
979 if (sock == NULL || sock->sk == NULL)
982 ssp = sock->sk->sk_security;
984 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
986 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0)
991 ilen = strlen(isp) + 1;
1002 * smack_inode_listsecurity - list the Smack attributes
1003 * @inode: the object
1004 * @buffer: where they go
1005 * @buffer_size: size of buffer
1007 * Returns 0 on success, -EINVAL otherwise
1009 static int smack_inode_listsecurity(struct inode *inode, char *buffer,
1012 int len = strlen(XATTR_NAME_SMACK);
1014 if (buffer != NULL && len <= buffer_size) {
1015 memcpy(buffer, XATTR_NAME_SMACK, len);
1022 * smack_inode_getsecid - Extract inode's security id
1023 * @inode: inode to extract the info from
1024 * @secid: where result will be saved
1026 static void smack_inode_getsecid(const struct inode *inode, u32 *secid)
1028 struct inode_smack *isp = inode->i_security;
1030 *secid = smack_to_secid(isp->smk_inode);
1038 * smack_file_permission - Smack check on file operations
1044 * Should access checks be done on each read or write?
1045 * UNICOS and SELinux say yes.
1046 * Trusted Solaris, Trusted Irix, and just about everyone else says no.
1048 * I'll say no for now. Smack does not do the frequent
1049 * label changing that SELinux does.
1051 static int smack_file_permission(struct file *file, int mask)
1057 * smack_file_alloc_security - assign a file security blob
1060 * The security blob for a file is a pointer to the master
1061 * label list, so no allocation is done.
1065 static int smack_file_alloc_security(struct file *file)
1067 file->f_security = smk_of_current();
1072 * smack_file_free_security - clear a file security blob
1075 * The security blob for a file is a pointer to the master
1076 * label list, so no memory is freed.
1078 static void smack_file_free_security(struct file *file)
1080 file->f_security = NULL;
1084 * smack_file_ioctl - Smack check on ioctls
1089 * Relies heavily on the correct use of the ioctl command conventions.
1091 * Returns 0 if allowed, error code otherwise
1093 static int smack_file_ioctl(struct file *file, unsigned int cmd,
1097 struct smk_audit_info ad;
1099 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1100 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1102 if (_IOC_DIR(cmd) & _IOC_WRITE)
1103 rc = smk_curacc(file->f_security, MAY_WRITE, &ad);
1105 if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ))
1106 rc = smk_curacc(file->f_security, MAY_READ, &ad);
1112 * smack_file_lock - Smack check on file locking
1116 * Returns 0 if current has write access, error code otherwise
1118 static int smack_file_lock(struct file *file, unsigned int cmd)
1120 struct smk_audit_info ad;
1122 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1123 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1124 return smk_curacc(file->f_security, MAY_WRITE, &ad);
1128 * smack_file_fcntl - Smack check on fcntl
1130 * @cmd: what action to check
1133 * Generally these operations are harmless.
1134 * File locking operations present an obvious mechanism
1135 * for passing information, so they require write access.
1137 * Returns 0 if current has access, error code otherwise
1139 static int smack_file_fcntl(struct file *file, unsigned int cmd,
1142 struct smk_audit_info ad;
1152 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH);
1153 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1154 rc = smk_curacc(file->f_security, MAY_WRITE, &ad);
1165 * Check permissions for a mmap operation. The @file may be NULL, e.g.
1166 * if mapping anonymous memory.
1167 * @file contains the file structure for file to map (may be NULL).
1168 * @reqprot contains the protection requested by the application.
1169 * @prot contains the protection that will be applied by the kernel.
1170 * @flags contains the operational flags.
1171 * Return 0 if permission is granted.
1173 static int smack_file_mmap(struct file *file,
1174 unsigned long reqprot, unsigned long prot,
1175 unsigned long flags, unsigned long addr,
1176 unsigned long addr_only)
1178 struct smack_known *skp;
1179 struct smack_rule *srp;
1180 struct task_smack *tsp;
1184 struct inode_smack *isp;
1191 /* do DAC check on address space usage */
1192 rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
1193 if (rc || addr_only)
1196 if (file == NULL || file->f_dentry == NULL)
1199 dp = file->f_dentry;
1201 if (dp->d_inode == NULL)
1204 isp = dp->d_inode->i_security;
1205 if (isp->smk_mmap == NULL)
1207 msmack = isp->smk_mmap;
1209 tsp = current_security();
1210 sp = smk_of_current();
1211 skp = smk_find_entry(sp);
1216 * For each Smack rule associated with the subject
1217 * label verify that the SMACK64MMAP also has access
1218 * to that rule's object label.
1220 list_for_each_entry_rcu(srp, &skp->smk_rules, list) {
1221 osmack = srp->smk_object;
1223 * Matching labels always allows access.
1225 if (msmack == osmack)
1228 * If there is a matching local rule take
1229 * that into account as well.
1231 may = smk_access_entry(srp->smk_subject, osmack,
1234 may = srp->smk_access;
1236 may &= srp->smk_access;
1238 * If may is zero the SMACK64MMAP subject can't
1239 * possibly have less access.
1245 * Fetch the global list entry.
1246 * If there isn't one a SMACK64MMAP subject
1247 * can't have as much access as current.
1249 skp = smk_find_entry(msmack);
1250 mmay = smk_access_entry(msmack, osmack, &skp->smk_rules);
1251 if (mmay == -ENOENT) {
1256 * If there is a local entry it modifies the
1257 * potential access, too.
1259 tmay = smk_access_entry(msmack, osmack, &tsp->smk_rules);
1260 if (tmay != -ENOENT)
1264 * If there is any access available to current that is
1265 * not available to a SMACK64MMAP subject
1268 if ((may | mmay) != mmay) {
1280 * smack_file_set_fowner - set the file security blob value
1281 * @file: object in question
1284 * Further research may be required on this one.
1286 static int smack_file_set_fowner(struct file *file)
1288 file->f_security = smk_of_current();
1293 * smack_file_send_sigiotask - Smack on sigio
1294 * @tsk: The target task
1295 * @fown: the object the signal come from
1298 * Allow a privileged task to get signals even if it shouldn't
1300 * Returns 0 if a subject with the object's smack could
1301 * write to the task, an error code otherwise.
1303 static int smack_file_send_sigiotask(struct task_struct *tsk,
1304 struct fown_struct *fown, int signum)
1308 char *tsp = smk_of_task(tsk->cred->security);
1309 struct smk_audit_info ad;
1312 * struct fown_struct is never outside the context of a struct file
1314 file = container_of(fown, struct file, f_owner);
1316 /* we don't log here as rc can be overriden */
1317 rc = smk_access(file->f_security, tsp, MAY_WRITE, NULL);
1318 if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE))
1321 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1322 smk_ad_setfield_u_tsk(&ad, tsk);
1323 smack_log(file->f_security, tsp, MAY_WRITE, rc, &ad);
1328 * smack_file_receive - Smack file receive check
1331 * Returns 0 if current has access, error code otherwise
1333 static int smack_file_receive(struct file *file)
1336 struct smk_audit_info ad;
1338 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1339 smk_ad_setfield_u_fs_path(&ad, file->f_path);
1341 * This code relies on bitmasks.
1343 if (file->f_mode & FMODE_READ)
1345 if (file->f_mode & FMODE_WRITE)
1348 return smk_curacc(file->f_security, may, &ad);
1352 * smack_dentry_open - Smack dentry open processing
1356 * Set the security blob in the file structure.
1360 static int smack_dentry_open(struct file *file, const struct cred *cred)
1362 struct inode_smack *isp = file->f_path.dentry->d_inode->i_security;
1364 file->f_security = isp->smk_inode;
1374 * smack_cred_alloc_blank - "allocate" blank task-level security credentials
1375 * @new: the new credentials
1376 * @gfp: the atomicity of any memory allocations
1378 * Prepare a blank set of credentials for modification. This must allocate all
1379 * the memory the LSM module might require such that cred_transfer() can
1380 * complete without error.
1382 static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp)
1384 struct task_smack *tsp;
1386 tsp = new_task_smack(NULL, NULL, gfp);
1390 cred->security = tsp;
1397 * smack_cred_free - "free" task-level security credentials
1398 * @cred: the credentials in question
1401 static void smack_cred_free(struct cred *cred)
1403 struct task_smack *tsp = cred->security;
1404 struct smack_rule *rp;
1405 struct list_head *l;
1406 struct list_head *n;
1410 cred->security = NULL;
1412 list_for_each_safe(l, n, &tsp->smk_rules) {
1413 rp = list_entry(l, struct smack_rule, list);
1414 list_del(&rp->list);
1421 * smack_cred_prepare - prepare new set of credentials for modification
1422 * @new: the new credentials
1423 * @old: the original credentials
1424 * @gfp: the atomicity of any memory allocations
1426 * Prepare a new set of credentials for modification.
1428 static int smack_cred_prepare(struct cred *new, const struct cred *old,
1431 struct task_smack *old_tsp = old->security;
1432 struct task_smack *new_tsp;
1435 new_tsp = new_task_smack(old_tsp->smk_task, old_tsp->smk_task, gfp);
1436 if (new_tsp == NULL)
1439 rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp);
1443 new->security = new_tsp;
1448 * smack_cred_transfer - Transfer the old credentials to the new credentials
1449 * @new: the new credentials
1450 * @old: the original credentials
1452 * Fill in a set of blank credentials from another set of credentials.
1454 static void smack_cred_transfer(struct cred *new, const struct cred *old)
1456 struct task_smack *old_tsp = old->security;
1457 struct task_smack *new_tsp = new->security;
1459 new_tsp->smk_task = old_tsp->smk_task;
1460 new_tsp->smk_forked = old_tsp->smk_task;
1461 mutex_init(&new_tsp->smk_rules_lock);
1462 INIT_LIST_HEAD(&new_tsp->smk_rules);
1465 /* cbs copy rule list */
1469 * smack_kernel_act_as - Set the subjective context in a set of credentials
1470 * @new: points to the set of credentials to be modified.
1471 * @secid: specifies the security ID to be set
1473 * Set the security data for a kernel service.
1475 static int smack_kernel_act_as(struct cred *new, u32 secid)
1477 struct task_smack *new_tsp = new->security;
1478 char *smack = smack_from_secid(secid);
1483 new_tsp->smk_task = smack;
1488 * smack_kernel_create_files_as - Set the file creation label in a set of creds
1489 * @new: points to the set of credentials to be modified
1490 * @inode: points to the inode to use as a reference
1492 * Set the file creation context in a set of credentials to the same
1493 * as the objective context of the specified inode
1495 static int smack_kernel_create_files_as(struct cred *new,
1496 struct inode *inode)
1498 struct inode_smack *isp = inode->i_security;
1499 struct task_smack *tsp = new->security;
1501 tsp->smk_forked = isp->smk_inode;
1502 tsp->smk_task = isp->smk_inode;
1507 * smk_curacc_on_task - helper to log task related access
1508 * @p: the task object
1509 * @access: the access requested
1510 * @caller: name of the calling function for audit
1512 * Return 0 if access is permitted
1514 static int smk_curacc_on_task(struct task_struct *p, int access,
1517 struct smk_audit_info ad;
1519 smk_ad_init(&ad, caller, LSM_AUDIT_DATA_TASK);
1520 smk_ad_setfield_u_tsk(&ad, p);
1521 return smk_curacc(smk_of_task(task_security(p)), access, &ad);
1525 * smack_task_setpgid - Smack check on setting pgid
1526 * @p: the task object
1529 * Return 0 if write access is permitted
1531 static int smack_task_setpgid(struct task_struct *p, pid_t pgid)
1533 return smk_curacc_on_task(p, MAY_WRITE, __func__);
1537 * smack_task_getpgid - Smack access check for getpgid
1538 * @p: the object task
1540 * Returns 0 if current can read the object task, error code otherwise
1542 static int smack_task_getpgid(struct task_struct *p)
1544 return smk_curacc_on_task(p, MAY_READ, __func__);
1548 * smack_task_getsid - Smack access check for getsid
1549 * @p: the object task
1551 * Returns 0 if current can read the object task, error code otherwise
1553 static int smack_task_getsid(struct task_struct *p)
1555 return smk_curacc_on_task(p, MAY_READ, __func__);
1559 * smack_task_getsecid - get the secid of the task
1560 * @p: the object task
1561 * @secid: where to put the result
1563 * Sets the secid to contain a u32 version of the smack label.
1565 static void smack_task_getsecid(struct task_struct *p, u32 *secid)
1567 *secid = smack_to_secid(smk_of_task(task_security(p)));
1571 * smack_task_setnice - Smack check on setting nice
1572 * @p: the task object
1575 * Return 0 if write access is permitted
1577 static int smack_task_setnice(struct task_struct *p, int nice)
1581 rc = cap_task_setnice(p, nice);
1583 rc = smk_curacc_on_task(p, MAY_WRITE, __func__);
1588 * smack_task_setioprio - Smack check on setting ioprio
1589 * @p: the task object
1592 * Return 0 if write access is permitted
1594 static int smack_task_setioprio(struct task_struct *p, int ioprio)
1598 rc = cap_task_setioprio(p, ioprio);
1600 rc = smk_curacc_on_task(p, MAY_WRITE, __func__);
1605 * smack_task_getioprio - Smack check on reading ioprio
1606 * @p: the task object
1608 * Return 0 if read access is permitted
1610 static int smack_task_getioprio(struct task_struct *p)
1612 return smk_curacc_on_task(p, MAY_READ, __func__);
1616 * smack_task_setscheduler - Smack check on setting scheduler
1617 * @p: the task object
1621 * Return 0 if read access is permitted
1623 static int smack_task_setscheduler(struct task_struct *p)
1627 rc = cap_task_setscheduler(p);
1629 rc = smk_curacc_on_task(p, MAY_WRITE, __func__);
1634 * smack_task_getscheduler - Smack check on reading scheduler
1635 * @p: the task object
1637 * Return 0 if read access is permitted
1639 static int smack_task_getscheduler(struct task_struct *p)
1641 return smk_curacc_on_task(p, MAY_READ, __func__);
1645 * smack_task_movememory - Smack check on moving memory
1646 * @p: the task object
1648 * Return 0 if write access is permitted
1650 static int smack_task_movememory(struct task_struct *p)
1652 return smk_curacc_on_task(p, MAY_WRITE, __func__);
1656 * smack_task_kill - Smack check on signal delivery
1657 * @p: the task object
1660 * @secid: identifies the smack to use in lieu of current's
1662 * Return 0 if write access is permitted
1664 * The secid behavior is an artifact of an SELinux hack
1665 * in the USB code. Someday it may go away.
1667 static int smack_task_kill(struct task_struct *p, struct siginfo *info,
1670 struct smk_audit_info ad;
1672 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1673 smk_ad_setfield_u_tsk(&ad, p);
1675 * Sending a signal requires that the sender
1676 * can write the receiver.
1679 return smk_curacc(smk_of_task(task_security(p)), MAY_WRITE,
1682 * If the secid isn't 0 we're dealing with some USB IO
1683 * specific behavior. This is not clean. For one thing
1684 * we can't take privilege into account.
1686 return smk_access(smack_from_secid(secid),
1687 smk_of_task(task_security(p)), MAY_WRITE, &ad);
1691 * smack_task_wait - Smack access check for waiting
1692 * @p: task to wait for
1694 * Returns 0 if current can wait for p, error code otherwise
1696 static int smack_task_wait(struct task_struct *p)
1698 struct smk_audit_info ad;
1699 char *sp = smk_of_current();
1700 char *tsp = smk_of_forked(task_security(p));
1703 /* we don't log here, we can be overriden */
1704 rc = smk_access(tsp, sp, MAY_WRITE, NULL);
1709 * Allow the operation to succeed if either task
1710 * has privilege to perform operations that might
1711 * account for the smack labels having gotten to
1712 * be different in the first place.
1714 * This breaks the strict subject/object access
1715 * control ideal, taking the object's privilege
1716 * state into account in the decision as well as
1719 if (capable(CAP_MAC_OVERRIDE) || has_capability(p, CAP_MAC_OVERRIDE))
1721 /* we log only if we didn't get overriden */
1723 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK);
1724 smk_ad_setfield_u_tsk(&ad, p);
1725 smack_log(tsp, sp, MAY_WRITE, rc, &ad);
1730 * smack_task_to_inode - copy task smack into the inode blob
1731 * @p: task to copy from
1732 * @inode: inode to copy to
1734 * Sets the smack pointer in the inode security blob
1736 static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
1738 struct inode_smack *isp = inode->i_security;
1739 isp->smk_inode = smk_of_task(task_security(p));
1747 * smack_sk_alloc_security - Allocate a socket blob
1750 * @gfp_flags: memory allocation flags
1752 * Assign Smack pointers to current
1754 * Returns 0 on success, -ENOMEM is there's no memory
1756 static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags)
1758 char *csp = smk_of_current();
1759 struct socket_smack *ssp;
1761 ssp = kzalloc(sizeof(struct socket_smack), gfp_flags);
1767 ssp->smk_packet = NULL;
1769 sk->sk_security = ssp;
1775 * smack_sk_free_security - Free a socket blob
1778 * Clears the blob pointer
1780 static void smack_sk_free_security(struct sock *sk)
1782 kfree(sk->sk_security);
1786 * smack_host_label - check host based restrictions
1787 * @sip: the object end
1789 * looks for host based access restrictions
1791 * This version will only be appropriate for really small sets of single label
1792 * hosts. The caller is responsible for ensuring that the RCU read lock is
1793 * taken before calling this function.
1795 * Returns the label of the far end or NULL if it's not special.
1797 static char *smack_host_label(struct sockaddr_in *sip)
1799 struct smk_netlbladdr *snp;
1800 struct in_addr *siap = &sip->sin_addr;
1802 if (siap->s_addr == 0)
1805 list_for_each_entry_rcu(snp, &smk_netlbladdr_list, list)
1807 * we break after finding the first match because
1808 * the list is sorted from longest to shortest mask
1809 * so we have found the most specific match
1811 if ((&snp->smk_host.sin_addr)->s_addr ==
1812 (siap->s_addr & (&snp->smk_mask)->s_addr)) {
1813 /* we have found the special CIPSO option */
1814 if (snp->smk_label == smack_cipso_option)
1816 return snp->smk_label;
1823 * smack_set_catset - convert a capset to netlabel mls categories
1824 * @catset: the Smack categories
1825 * @sap: where to put the netlabel categories
1827 * Allocates and fills attr.mls.cat
1829 static void smack_set_catset(char *catset, struct netlbl_lsm_secattr *sap)
1840 sap->flags |= NETLBL_SECATTR_MLS_CAT;
1841 sap->attr.mls.cat = netlbl_secattr_catmap_alloc(GFP_ATOMIC);
1842 sap->attr.mls.cat->startbit = 0;
1844 for (cat = 1, cp = catset, byte = 0; byte < SMK_LABELLEN; cp++, byte++)
1845 for (m = 0x80; m != 0; m >>= 1, cat++) {
1848 rc = netlbl_secattr_catmap_setbit(sap->attr.mls.cat,
1854 * smack_to_secattr - fill a secattr from a smack value
1855 * @smack: the smack value
1856 * @nlsp: where the result goes
1858 * Casey says that CIPSO is good enough for now.
1859 * It can be used to effect.
1860 * It can also be abused to effect when necessary.
1861 * Apologies to the TSIG group in general and GW in particular.
1863 static void smack_to_secattr(char *smack, struct netlbl_lsm_secattr *nlsp)
1865 struct smack_cipso cipso;
1868 nlsp->domain = smack;
1869 nlsp->flags = NETLBL_SECATTR_DOMAIN | NETLBL_SECATTR_MLS_LVL;
1871 rc = smack_to_cipso(smack, &cipso);
1873 nlsp->attr.mls.lvl = cipso.smk_level;
1874 smack_set_catset(cipso.smk_catset, nlsp);
1876 nlsp->attr.mls.lvl = smack_cipso_direct;
1877 smack_set_catset(smack, nlsp);
1882 * smack_netlabel - Set the secattr on a socket
1884 * @labeled: socket label scheme
1886 * Convert the outbound smack value (smk_out) to a
1887 * secattr and attach it to the socket.
1889 * Returns 0 on success or an error code
1891 static int smack_netlabel(struct sock *sk, int labeled)
1893 struct socket_smack *ssp = sk->sk_security;
1894 struct netlbl_lsm_secattr secattr;
1898 * Usually the netlabel code will handle changing the
1899 * packet labeling based on the label.
1900 * The case of a single label host is different, because
1901 * a single label host should never get a labeled packet
1902 * even though the label is usually associated with a packet
1906 bh_lock_sock_nested(sk);
1908 if (ssp->smk_out == smack_net_ambient ||
1909 labeled == SMACK_UNLABELED_SOCKET)
1910 netlbl_sock_delattr(sk);
1912 netlbl_secattr_init(&secattr);
1913 smack_to_secattr(ssp->smk_out, &secattr);
1914 rc = netlbl_sock_setattr(sk, sk->sk_family, &secattr);
1915 netlbl_secattr_destroy(&secattr);
1925 * smack_netlbel_send - Set the secattr on a socket and perform access checks
1927 * @sap: the destination address
1929 * Set the correct secattr for the given socket based on the destination
1930 * address and perform any outbound access checks needed.
1932 * Returns 0 on success or an error code.
1935 static int smack_netlabel_send(struct sock *sk, struct sockaddr_in *sap)
1940 struct socket_smack *ssp = sk->sk_security;
1941 struct smk_audit_info ad;
1942 struct lsm_network_audit net;
1945 hostsp = smack_host_label(sap);
1946 if (hostsp != NULL) {
1947 sk_lbl = SMACK_UNLABELED_SOCKET;
1949 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
1950 ad.a.u.net->family = sap->sin_family;
1951 ad.a.u.net->dport = sap->sin_port;
1952 ad.a.u.net->v4info.daddr = sap->sin_addr.s_addr;
1954 rc = smk_access(ssp->smk_out, hostsp, MAY_WRITE, &ad);
1956 sk_lbl = SMACK_CIPSO_SOCKET;
1963 return smack_netlabel(sk, sk_lbl);
1967 * smack_inode_setsecurity - set smack xattrs
1968 * @inode: the object
1969 * @name: attribute name
1970 * @value: attribute value
1971 * @size: size of the attribute
1974 * Sets the named attribute in the appropriate blob
1976 * Returns 0 on success, or an error code
1978 static int smack_inode_setsecurity(struct inode *inode, const char *name,
1979 const void *value, size_t size, int flags)
1982 struct inode_smack *nsp = inode->i_security;
1983 struct socket_smack *ssp;
1984 struct socket *sock;
1987 if (value == NULL || size > SMK_LABELLEN || size == 0)
1990 sp = smk_import(value, size);
1994 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
1995 nsp->smk_inode = sp;
1996 nsp->smk_flags |= SMK_INODE_INSTANT;
2000 * The rest of the Smack xattrs are only on sockets.
2002 if (inode->i_sb->s_magic != SOCKFS_MAGIC)
2005 sock = SOCKET_I(inode);
2006 if (sock == NULL || sock->sk == NULL)
2009 ssp = sock->sk->sk_security;
2011 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
2013 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) {
2015 if (sock->sk->sk_family != PF_UNIX) {
2016 rc = smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
2019 "Smack: \"%s\" netlbl error %d.\n",
2029 * smack_socket_post_create - finish socket setup
2031 * @family: protocol family
2036 * Sets the netlabel information on the socket
2038 * Returns 0 on success, and error code otherwise
2040 static int smack_socket_post_create(struct socket *sock, int family,
2041 int type, int protocol, int kern)
2043 if (family != PF_INET || sock->sk == NULL)
2046 * Set the outbound netlbl.
2048 return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET);
2052 * smack_socket_connect - connect access check
2054 * @sap: the other end
2055 * @addrlen: size of sap
2057 * Verifies that a connection may be possible
2059 * Returns 0 on success, and error code otherwise
2061 static int smack_socket_connect(struct socket *sock, struct sockaddr *sap,
2064 if (sock->sk == NULL || sock->sk->sk_family != PF_INET)
2066 if (addrlen < sizeof(struct sockaddr_in))
2069 return smack_netlabel_send(sock->sk, (struct sockaddr_in *)sap);
2073 * smack_flags_to_may - convert S_ to MAY_ values
2074 * @flags: the S_ value
2076 * Returns the equivalent MAY_ value
2078 static int smack_flags_to_may(int flags)
2082 if (flags & S_IRUGO)
2084 if (flags & S_IWUGO)
2086 if (flags & S_IXUGO)
2093 * smack_msg_msg_alloc_security - Set the security blob for msg_msg
2098 static int smack_msg_msg_alloc_security(struct msg_msg *msg)
2100 msg->security = smk_of_current();
2105 * smack_msg_msg_free_security - Clear the security blob for msg_msg
2108 * Clears the blob pointer
2110 static void smack_msg_msg_free_security(struct msg_msg *msg)
2112 msg->security = NULL;
2116 * smack_of_shm - the smack pointer for the shm
2119 * Returns a pointer to the smack value
2121 static char *smack_of_shm(struct shmid_kernel *shp)
2123 return (char *)shp->shm_perm.security;
2127 * smack_shm_alloc_security - Set the security blob for shm
2132 static int smack_shm_alloc_security(struct shmid_kernel *shp)
2134 struct kern_ipc_perm *isp = &shp->shm_perm;
2136 isp->security = smk_of_current();
2141 * smack_shm_free_security - Clear the security blob for shm
2144 * Clears the blob pointer
2146 static void smack_shm_free_security(struct shmid_kernel *shp)
2148 struct kern_ipc_perm *isp = &shp->shm_perm;
2150 isp->security = NULL;
2154 * smk_curacc_shm : check if current has access on shm
2156 * @access : access requested
2158 * Returns 0 if current has the requested access, error code otherwise
2160 static int smk_curacc_shm(struct shmid_kernel *shp, int access)
2162 char *ssp = smack_of_shm(shp);
2163 struct smk_audit_info ad;
2166 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
2167 ad.a.u.ipc_id = shp->shm_perm.id;
2169 return smk_curacc(ssp, access, &ad);
2173 * smack_shm_associate - Smack access check for shm
2175 * @shmflg: access requested
2177 * Returns 0 if current has the requested access, error code otherwise
2179 static int smack_shm_associate(struct shmid_kernel *shp, int shmflg)
2183 may = smack_flags_to_may(shmflg);
2184 return smk_curacc_shm(shp, may);
2188 * smack_shm_shmctl - Smack access check for shm
2190 * @cmd: what it wants to do
2192 * Returns 0 if current has the requested access, error code otherwise
2194 static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd)
2207 may = MAY_READWRITE;
2212 * System level information.
2218 return smk_curacc_shm(shp, may);
2222 * smack_shm_shmat - Smack access for shmat
2225 * @shmflg: access requested
2227 * Returns 0 if current has the requested access, error code otherwise
2229 static int smack_shm_shmat(struct shmid_kernel *shp, char __user *shmaddr,
2234 may = smack_flags_to_may(shmflg);
2235 return smk_curacc_shm(shp, may);
2239 * smack_of_sem - the smack pointer for the sem
2242 * Returns a pointer to the smack value
2244 static char *smack_of_sem(struct sem_array *sma)
2246 return (char *)sma->sem_perm.security;
2250 * smack_sem_alloc_security - Set the security blob for sem
2255 static int smack_sem_alloc_security(struct sem_array *sma)
2257 struct kern_ipc_perm *isp = &sma->sem_perm;
2259 isp->security = smk_of_current();
2264 * smack_sem_free_security - Clear the security blob for sem
2267 * Clears the blob pointer
2269 static void smack_sem_free_security(struct sem_array *sma)
2271 struct kern_ipc_perm *isp = &sma->sem_perm;
2273 isp->security = NULL;
2277 * smk_curacc_sem : check if current has access on sem
2279 * @access : access requested
2281 * Returns 0 if current has the requested access, error code otherwise
2283 static int smk_curacc_sem(struct sem_array *sma, int access)
2285 char *ssp = smack_of_sem(sma);
2286 struct smk_audit_info ad;
2289 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
2290 ad.a.u.ipc_id = sma->sem_perm.id;
2292 return smk_curacc(ssp, access, &ad);
2296 * smack_sem_associate - Smack access check for sem
2298 * @semflg: access requested
2300 * Returns 0 if current has the requested access, error code otherwise
2302 static int smack_sem_associate(struct sem_array *sma, int semflg)
2306 may = smack_flags_to_may(semflg);
2307 return smk_curacc_sem(sma, may);
2311 * smack_sem_shmctl - Smack access check for sem
2313 * @cmd: what it wants to do
2315 * Returns 0 if current has the requested access, error code otherwise
2317 static int smack_sem_semctl(struct sem_array *sma, int cmd)
2335 may = MAY_READWRITE;
2340 * System level information
2347 return smk_curacc_sem(sma, may);
2351 * smack_sem_semop - Smack checks of semaphore operations
2357 * Treated as read and write in all cases.
2359 * Returns 0 if access is allowed, error code otherwise
2361 static int smack_sem_semop(struct sem_array *sma, struct sembuf *sops,
2362 unsigned nsops, int alter)
2364 return smk_curacc_sem(sma, MAY_READWRITE);
2368 * smack_msg_alloc_security - Set the security blob for msg
2373 static int smack_msg_queue_alloc_security(struct msg_queue *msq)
2375 struct kern_ipc_perm *kisp = &msq->q_perm;
2377 kisp->security = smk_of_current();
2382 * smack_msg_free_security - Clear the security blob for msg
2385 * Clears the blob pointer
2387 static void smack_msg_queue_free_security(struct msg_queue *msq)
2389 struct kern_ipc_perm *kisp = &msq->q_perm;
2391 kisp->security = NULL;
2395 * smack_of_msq - the smack pointer for the msq
2398 * Returns a pointer to the smack value
2400 static char *smack_of_msq(struct msg_queue *msq)
2402 return (char *)msq->q_perm.security;
2406 * smk_curacc_msq : helper to check if current has access on msq
2408 * @access : access requested
2410 * return 0 if current has access, error otherwise
2412 static int smk_curacc_msq(struct msg_queue *msq, int access)
2414 char *msp = smack_of_msq(msq);
2415 struct smk_audit_info ad;
2418 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
2419 ad.a.u.ipc_id = msq->q_perm.id;
2421 return smk_curacc(msp, access, &ad);
2425 * smack_msg_queue_associate - Smack access check for msg_queue
2427 * @msqflg: access requested
2429 * Returns 0 if current has the requested access, error code otherwise
2431 static int smack_msg_queue_associate(struct msg_queue *msq, int msqflg)
2435 may = smack_flags_to_may(msqflg);
2436 return smk_curacc_msq(msq, may);
2440 * smack_msg_queue_msgctl - Smack access check for msg_queue
2442 * @cmd: what it wants to do
2444 * Returns 0 if current has the requested access, error code otherwise
2446 static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd)
2457 may = MAY_READWRITE;
2462 * System level information
2469 return smk_curacc_msq(msq, may);
2473 * smack_msg_queue_msgsnd - Smack access check for msg_queue
2476 * @msqflg: access requested
2478 * Returns 0 if current has the requested access, error code otherwise
2480 static int smack_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg,
2485 may = smack_flags_to_may(msqflg);
2486 return smk_curacc_msq(msq, may);
2490 * smack_msg_queue_msgsnd - Smack access check for msg_queue
2497 * Returns 0 if current has read and write access, error code otherwise
2499 static int smack_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
2500 struct task_struct *target, long type, int mode)
2502 return smk_curacc_msq(msq, MAY_READWRITE);
2506 * smack_ipc_permission - Smack access for ipc_permission()
2507 * @ipp: the object permissions
2508 * @flag: access requested
2510 * Returns 0 if current has read and write access, error code otherwise
2512 static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag)
2514 char *isp = ipp->security;
2515 int may = smack_flags_to_may(flag);
2516 struct smk_audit_info ad;
2519 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC);
2520 ad.a.u.ipc_id = ipp->id;
2522 return smk_curacc(isp, may, &ad);
2526 * smack_ipc_getsecid - Extract smack security id
2527 * @ipp: the object permissions
2528 * @secid: where result will be saved
2530 static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid)
2532 char *smack = ipp->security;
2534 *secid = smack_to_secid(smack);
2538 * smack_d_instantiate - Make sure the blob is correct on an inode
2539 * @opt_dentry: dentry where inode will be attached
2540 * @inode: the object
2542 * Set the inode's security blob if it hasn't been done already.
2544 static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
2546 struct super_block *sbp;
2547 struct superblock_smack *sbsp;
2548 struct inode_smack *isp;
2549 char *csp = smk_of_current();
2552 char trattr[TRANS_TRUE_SIZE];
2559 isp = inode->i_security;
2561 mutex_lock(&isp->smk_lock);
2563 * If the inode is already instantiated
2564 * take the quick way out
2566 if (isp->smk_flags & SMK_INODE_INSTANT)
2570 sbsp = sbp->s_security;
2572 * We're going to use the superblock default label
2573 * if there's no label on the file.
2575 final = sbsp->smk_default;
2578 * If this is the root inode the superblock
2579 * may be in the process of initialization.
2580 * If that is the case use the root value out
2581 * of the superblock.
2583 if (opt_dentry->d_parent == opt_dentry) {
2584 isp->smk_inode = sbsp->smk_root;
2585 isp->smk_flags |= SMK_INODE_INSTANT;
2590 * This is pretty hackish.
2591 * Casey says that we shouldn't have to do
2592 * file system specific code, but it does help
2593 * with keeping it simple.
2595 switch (sbp->s_magic) {
2598 * Casey says that it's a little embarrassing
2599 * that the smack file system doesn't do
2600 * extended attributes.
2602 final = smack_known_star.smk_known;
2606 * Casey says pipes are easy (?)
2608 final = smack_known_star.smk_known;
2610 case DEVPTS_SUPER_MAGIC:
2612 * devpts seems content with the label of the task.
2613 * Programs that change smack have to treat the
2620 * Socket access is controlled by the socket
2621 * structures associated with the task involved.
2623 final = smack_known_star.smk_known;
2625 case PROC_SUPER_MAGIC:
2627 * Casey says procfs appears not to care.
2628 * The superblock default suffices.
2633 * Device labels should come from the filesystem,
2634 * but watch out, because they're volitile,
2635 * getting recreated on every reboot.
2637 final = smack_known_star.smk_known;
2641 * If a smack value has been set we want to use it,
2642 * but since tmpfs isn't giving us the opportunity
2643 * to set mount options simulate setting the
2644 * superblock default.
2648 * This isn't an understood special case.
2649 * Get the value from the xattr.
2653 * UNIX domain sockets use lower level socket data.
2655 if (S_ISSOCK(inode->i_mode)) {
2656 final = smack_known_star.smk_known;
2660 * No xattr support means, alas, no SMACK label.
2661 * Use the aforeapplied default.
2662 * It would be curious if the label of the task
2663 * does not match that assigned.
2665 if (inode->i_op->getxattr == NULL)
2668 * Get the dentry for xattr.
2670 dp = dget(opt_dentry);
2671 fetched = smk_fetch(XATTR_NAME_SMACK, inode, dp);
2672 if (fetched != NULL) {
2674 if (S_ISDIR(inode->i_mode)) {
2676 inode->i_op->getxattr(dp,
2677 XATTR_NAME_SMACKTRANSMUTE,
2678 trattr, TRANS_TRUE_SIZE);
2679 if (strncmp(trattr, TRANS_TRUE,
2680 TRANS_TRUE_SIZE) == 0)
2681 transflag = SMK_INODE_TRANSMUTE;
2684 isp->smk_task = smk_fetch(XATTR_NAME_SMACKEXEC, inode, dp);
2685 isp->smk_mmap = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp);
2692 isp->smk_inode = csp;
2694 isp->smk_inode = final;
2696 isp->smk_flags |= (SMK_INODE_INSTANT | transflag);
2699 mutex_unlock(&isp->smk_lock);
2704 * smack_getprocattr - Smack process attribute access
2705 * @p: the object task
2706 * @name: the name of the attribute in /proc/.../attr
2707 * @value: where to put the result
2709 * Places a copy of the task Smack into value
2711 * Returns the length of the smack label or an error code
2713 static int smack_getprocattr(struct task_struct *p, char *name, char **value)
2718 if (strcmp(name, "current") != 0)
2721 cp = kstrdup(smk_of_task(task_security(p)), GFP_KERNEL);
2731 * smack_setprocattr - Smack process attribute setting
2732 * @p: the object task
2733 * @name: the name of the attribute in /proc/.../attr
2734 * @value: the value to set
2735 * @size: the size of the value
2737 * Sets the Smack value of the task. Only setting self
2738 * is permitted and only with privilege
2740 * Returns the length of the smack label or an error code
2742 static int smack_setprocattr(struct task_struct *p, char *name,
2743 void *value, size_t size)
2746 struct task_smack *tsp;
2747 struct task_smack *oldtsp;
2752 * Changing another process' Smack value is too dangerous
2753 * and supports no sane use case.
2758 if (!capable(CAP_MAC_ADMIN))
2761 if (value == NULL || size == 0 || size >= SMK_LABELLEN)
2764 if (strcmp(name, "current") != 0)
2767 newsmack = smk_import(value, size);
2768 if (newsmack == NULL)
2772 * No process is ever allowed the web ("@") label.
2774 if (newsmack == smack_known_web.smk_known)
2777 oldtsp = p->cred->security;
2778 new = prepare_creds();
2782 tsp = new_task_smack(newsmack, oldtsp->smk_forked, GFP_KERNEL);
2787 rc = smk_copy_rules(&tsp->smk_rules, &oldtsp->smk_rules, GFP_KERNEL);
2791 new->security = tsp;
2797 * smack_unix_stream_connect - Smack access on UDS
2799 * @other: the other sock
2802 * Return 0 if a subject with the smack of sock could access
2803 * an object with the smack of other, otherwise an error code
2805 static int smack_unix_stream_connect(struct sock *sock,
2806 struct sock *other, struct sock *newsk)
2808 struct socket_smack *ssp = sock->sk_security;
2809 struct socket_smack *osp = other->sk_security;
2810 struct socket_smack *nsp = newsk->sk_security;
2811 struct smk_audit_info ad;
2812 struct lsm_network_audit net;
2815 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
2816 smk_ad_setfield_u_net_sk(&ad, other);
2818 if (!capable(CAP_MAC_OVERRIDE))
2819 rc = smk_access(ssp->smk_out, osp->smk_in, MAY_WRITE, &ad);
2822 * Cross reference the peer labels for SO_PEERSEC.
2825 nsp->smk_packet = ssp->smk_out;
2826 ssp->smk_packet = osp->smk_out;
2833 * smack_unix_may_send - Smack access on UDS
2835 * @other: the other socket
2837 * Return 0 if a subject with the smack of sock could access
2838 * an object with the smack of other, otherwise an error code
2840 static int smack_unix_may_send(struct socket *sock, struct socket *other)
2842 struct socket_smack *ssp = sock->sk->sk_security;
2843 struct socket_smack *osp = other->sk->sk_security;
2844 struct smk_audit_info ad;
2845 struct lsm_network_audit net;
2848 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
2849 smk_ad_setfield_u_net_sk(&ad, other->sk);
2851 if (!capable(CAP_MAC_OVERRIDE))
2852 rc = smk_access(ssp->smk_out, osp->smk_in, MAY_WRITE, &ad);
2858 * smack_socket_sendmsg - Smack check based on destination host
2861 * @size: the size of the message
2863 * Return 0 if the current subject can write to the destination
2864 * host. This is only a question if the destination is a single
2867 static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg,
2870 struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name;
2873 * Perfectly reasonable for this to be NULL
2875 if (sip == NULL || sip->sin_family != AF_INET)
2878 return smack_netlabel_send(sock->sk, sip);
2882 * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat pair to smack
2883 * @sap: netlabel secattr
2884 * @ssp: socket security information
2886 * Returns a pointer to a Smack label found on the label list.
2888 static char *smack_from_secattr(struct netlbl_lsm_secattr *sap,
2889 struct socket_smack *ssp)
2891 struct smack_known *skp;
2892 char smack[SMK_LABELLEN];
2896 if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) {
2898 * Looks like a CIPSO packet.
2899 * If there are flags but no level netlabel isn't
2900 * behaving the way we expect it to.
2902 * Get the categories, if any
2903 * Without guidance regarding the smack value
2904 * for the packet fall back on the network
2907 memset(smack, '\0', SMK_LABELLEN);
2908 if ((sap->flags & NETLBL_SECATTR_MLS_CAT) != 0)
2910 pcat = netlbl_secattr_catmap_walk(
2911 sap->attr.mls.cat, pcat + 1);
2914 smack_catset_bit(pcat, smack);
2917 * If it is CIPSO using smack direct mapping
2918 * we are already done. WeeHee.
2920 if (sap->attr.mls.lvl == smack_cipso_direct) {
2922 * The label sent is usually on the label list.
2924 * If it is not we may still want to allow the
2927 * If the recipient is accepting all packets
2928 * because it is using the star ("*") label
2929 * for SMACK64IPIN provide the web ("@") label
2930 * so that a directed response will succeed.
2931 * This is not very correct from a MAC point
2932 * of view, but gets around the problem that
2933 * locking prevents adding the newly discovered
2934 * label to the list.
2935 * The case where the recipient is not using
2936 * the star label should obviously fail.
2937 * The easy way to do this is to provide the
2938 * star label as the subject label.
2940 skp = smk_find_entry(smack);
2942 return skp->smk_known;
2944 ssp->smk_in == smack_known_star.smk_known)
2945 return smack_known_web.smk_known;
2946 return smack_known_star.smk_known;
2949 * Look it up in the supplied table if it is not
2952 sp = smack_from_cipso(sap->attr.mls.lvl, smack);
2955 if (ssp != NULL && ssp->smk_in == smack_known_star.smk_known)
2956 return smack_known_web.smk_known;
2957 return smack_known_star.smk_known;
2959 if ((sap->flags & NETLBL_SECATTR_SECID) != 0) {
2961 * Looks like a fallback, which gives us a secid.
2963 sp = smack_from_secid(sap->attr.secid);
2965 * This has got to be a bug because it is
2966 * impossible to specify a fallback without
2967 * specifying the label, which will ensure
2968 * it has a secid, and the only way to get a
2969 * secid is from a fallback.
2975 * Without guidance regarding the smack value
2976 * for the packet fall back on the network
2979 return smack_net_ambient;
2983 * smack_socket_sock_rcv_skb - Smack packet delivery access check
2987 * Returns 0 if the packet should be delivered, an error code otherwise
2989 static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
2991 struct netlbl_lsm_secattr secattr;
2992 struct socket_smack *ssp = sk->sk_security;
2995 struct smk_audit_info ad;
2996 struct lsm_network_audit net;
2997 if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
3001 * Translate what netlabel gave us.
3003 netlbl_secattr_init(&secattr);
3005 rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr);
3007 csp = smack_from_secattr(&secattr, ssp);
3009 csp = smack_net_ambient;
3011 netlbl_secattr_destroy(&secattr);
3014 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
3015 ad.a.u.net->family = sk->sk_family;
3016 ad.a.u.net->netif = skb->skb_iif;
3017 ipv4_skb_to_auditdata(skb, &ad.a, NULL);
3020 * Receiving a packet requires that the other end
3021 * be able to write here. Read access is not required.
3022 * This is the simplist possible security model
3025 rc = smk_access(csp, ssp->smk_in, MAY_WRITE, &ad);
3027 netlbl_skbuff_err(skb, rc, 0);
3032 * smack_socket_getpeersec_stream - pull in packet label
3034 * @optval: user's destination
3035 * @optlen: size thereof
3038 * returns zero on success, an error code otherwise
3040 static int smack_socket_getpeersec_stream(struct socket *sock,
3041 char __user *optval,
3042 int __user *optlen, unsigned len)
3044 struct socket_smack *ssp;
3049 ssp = sock->sk->sk_security;
3050 if (ssp->smk_packet != NULL) {
3051 rcp = ssp->smk_packet;
3052 slen = strlen(rcp) + 1;
3057 else if (copy_to_user(optval, rcp, slen) != 0)
3060 if (put_user(slen, optlen) != 0)
3068 * smack_socket_getpeersec_dgram - pull in packet label
3069 * @sock: the peer socket
3071 * @secid: pointer to where to put the secid of the packet
3073 * Sets the netlabel socket state on sk from parent
3075 static int smack_socket_getpeersec_dgram(struct socket *sock,
3076 struct sk_buff *skb, u32 *secid)
3079 struct netlbl_lsm_secattr secattr;
3080 struct socket_smack *ssp = NULL;
3082 int family = PF_UNSPEC;
3083 u32 s = 0; /* 0 is the invalid secid */
3087 if (skb->protocol == htons(ETH_P_IP))
3089 else if (skb->protocol == htons(ETH_P_IPV6))
3092 if (family == PF_UNSPEC && sock != NULL)
3093 family = sock->sk->sk_family;
3095 if (family == PF_UNIX) {
3096 ssp = sock->sk->sk_security;
3097 s = smack_to_secid(ssp->smk_out);
3098 } else if (family == PF_INET || family == PF_INET6) {
3100 * Translate what netlabel gave us.
3102 if (sock != NULL && sock->sk != NULL)
3103 ssp = sock->sk->sk_security;
3104 netlbl_secattr_init(&secattr);
3105 rc = netlbl_skbuff_getattr(skb, family, &secattr);
3107 sp = smack_from_secattr(&secattr, ssp);
3108 s = smack_to_secid(sp);
3110 netlbl_secattr_destroy(&secattr);
3119 * smack_sock_graft - Initialize a newly created socket with an existing sock
3121 * @parent: parent socket
3123 * Set the smk_{in,out} state of an existing sock based on the process that
3124 * is creating the new socket.
3126 static void smack_sock_graft(struct sock *sk, struct socket *parent)
3128 struct socket_smack *ssp;
3131 (sk->sk_family != PF_INET && sk->sk_family != PF_INET6))
3134 ssp = sk->sk_security;
3135 ssp->smk_in = ssp->smk_out = smk_of_current();
3136 /* cssp->smk_packet is already set in smack_inet_csk_clone() */
3140 * smack_inet_conn_request - Smack access check on connect
3141 * @sk: socket involved
3145 * Returns 0 if a task with the packet label could write to
3146 * the socket, otherwise an error code
3148 static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb,
3149 struct request_sock *req)
3151 u16 family = sk->sk_family;
3152 struct socket_smack *ssp = sk->sk_security;
3153 struct netlbl_lsm_secattr secattr;
3154 struct sockaddr_in addr;
3158 struct smk_audit_info ad;
3159 struct lsm_network_audit net;
3161 /* handle mapped IPv4 packets arriving via IPv6 sockets */
3162 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
3165 netlbl_secattr_init(&secattr);
3166 rc = netlbl_skbuff_getattr(skb, family, &secattr);
3168 sp = smack_from_secattr(&secattr, ssp);
3170 sp = smack_known_huh.smk_known;
3171 netlbl_secattr_destroy(&secattr);
3174 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net);
3175 ad.a.u.net->family = family;
3176 ad.a.u.net->netif = skb->skb_iif;
3177 ipv4_skb_to_auditdata(skb, &ad.a, NULL);
3180 * Receiving a packet requires that the other end be able to write
3181 * here. Read access is not required.
3183 rc = smk_access(sp, ssp->smk_in, MAY_WRITE, &ad);
3188 * Save the peer's label in the request_sock so we can later setup
3189 * smk_packet in the child socket so that SO_PEERCRED can report it.
3191 req->peer_secid = smack_to_secid(sp);
3194 * We need to decide if we want to label the incoming connection here
3195 * if we do we only need to label the request_sock and the stack will
3196 * propagate the wire-label to the sock when it is created.
3199 addr.sin_addr.s_addr = hdr->saddr;
3201 if (smack_host_label(&addr) == NULL) {
3203 netlbl_secattr_init(&secattr);
3204 smack_to_secattr(sp, &secattr);
3205 rc = netlbl_req_setattr(req, &secattr);
3206 netlbl_secattr_destroy(&secattr);
3209 netlbl_req_delattr(req);
3216 * smack_inet_csk_clone - Copy the connection information to the new socket
3217 * @sk: the new socket
3218 * @req: the connection's request_sock
3220 * Transfer the connection's peer label to the newly created socket.
3222 static void smack_inet_csk_clone(struct sock *sk,
3223 const struct request_sock *req)
3225 struct socket_smack *ssp = sk->sk_security;
3227 if (req->peer_secid != 0)
3228 ssp->smk_packet = smack_from_secid(req->peer_secid);
3230 ssp->smk_packet = NULL;
3234 * Key management security hooks
3236 * Casey has not tested key support very heavily.
3237 * The permission check is most likely too restrictive.
3238 * If you care about keys please have a look.
3243 * smack_key_alloc - Set the key security blob
3245 * @cred: the credentials to use
3248 * No allocation required
3252 static int smack_key_alloc(struct key *key, const struct cred *cred,
3253 unsigned long flags)
3255 key->security = smk_of_task(cred->security);
3260 * smack_key_free - Clear the key security blob
3263 * Clear the blob pointer
3265 static void smack_key_free(struct key *key)
3267 key->security = NULL;
3271 * smack_key_permission - Smack access on a key
3272 * @key_ref: gets to the object
3273 * @cred: the credentials to use
3276 * Return 0 if the task has read and write to the object,
3277 * an error code otherwise
3279 static int smack_key_permission(key_ref_t key_ref,
3280 const struct cred *cred, key_perm_t perm)
3283 struct smk_audit_info ad;
3284 char *tsp = smk_of_task(cred->security);
3286 keyp = key_ref_to_ptr(key_ref);
3290 * If the key hasn't been initialized give it access so that
3293 if (keyp->security == NULL)
3296 * This should not occur
3301 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY);
3302 ad.a.u.key_struct.key = keyp->serial;
3303 ad.a.u.key_struct.key_desc = keyp->description;
3305 return smk_access(tsp, keyp->security,
3306 MAY_READWRITE, &ad);
3308 #endif /* CONFIG_KEYS */
3313 * Audit requires a unique representation of each Smack specific
3314 * rule. This unique representation is used to distinguish the
3315 * object to be audited from remaining kernel objects and also
3316 * works as a glue between the audit hooks.
3318 * Since repository entries are added but never deleted, we'll use
3319 * the smack_known label address related to the given audit rule as
3320 * the needed unique representation. This also better fits the smack
3321 * model where nearly everything is a label.
3326 * smack_audit_rule_init - Initialize a smack audit rule
3327 * @field: audit rule fields given from user-space (audit.h)
3328 * @op: required testing operator (=, !=, >, <, ...)
3329 * @rulestr: smack label to be audited
3330 * @vrule: pointer to save our own audit rule representation
3332 * Prepare to audit cases where (@field @op @rulestr) is true.
3333 * The label to be audited is created if necessay.
3335 static int smack_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
3337 char **rule = (char **)vrule;
3340 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
3343 if (op != Audit_equal && op != Audit_not_equal)
3346 *rule = smk_import(rulestr, 0);
3352 * smack_audit_rule_known - Distinguish Smack audit rules
3353 * @krule: rule of interest, in Audit kernel representation format
3355 * This is used to filter Smack rules from remaining Audit ones.
3356 * If it's proved that this rule belongs to us, the
3357 * audit_rule_match hook will be called to do the final judgement.
3359 static int smack_audit_rule_known(struct audit_krule *krule)
3361 struct audit_field *f;
3364 for (i = 0; i < krule->field_count; i++) {
3365 f = &krule->fields[i];
3367 if (f->type == AUDIT_SUBJ_USER || f->type == AUDIT_OBJ_USER)
3375 * smack_audit_rule_match - Audit given object ?
3376 * @secid: security id for identifying the object to test
3377 * @field: audit rule flags given from user-space
3378 * @op: required testing operator
3379 * @vrule: smack internal rule presentation
3380 * @actx: audit context associated with the check
3382 * The core Audit hook. It's used to take the decision of
3383 * whether to audit or not to audit a given object.
3385 static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule,
3386 struct audit_context *actx)
3392 audit_log(actx, GFP_KERNEL, AUDIT_SELINUX_ERR,
3393 "Smack: missing rule\n");
3397 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
3400 smack = smack_from_secid(secid);
3403 * No need to do string comparisons. If a match occurs,
3404 * both pointers will point to the same smack_known
3407 if (op == Audit_equal)
3408 return (rule == smack);
3409 if (op == Audit_not_equal)
3410 return (rule != smack);
3416 * smack_audit_rule_free - free smack rule representation
3417 * @vrule: rule to be freed.
3419 * No memory was allocated.
3421 static void smack_audit_rule_free(void *vrule)
3426 #endif /* CONFIG_AUDIT */
3429 * smack_secid_to_secctx - return the smack label for a secid
3430 * @secid: incoming integer
3431 * @secdata: destination
3432 * @seclen: how long it is
3434 * Exists for networking code.
3436 static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
3438 char *sp = smack_from_secid(secid);
3442 *seclen = strlen(sp);
3447 * smack_secctx_to_secid - return the secid for a smack label
3448 * @secdata: smack label
3449 * @seclen: how long result is
3450 * @secid: outgoing integer
3452 * Exists for audit and networking code.
3454 static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
3456 *secid = smack_to_secid(secdata);
3461 * smack_release_secctx - don't do anything.
3465 * Exists to make sure nothing gets done, and properly
3467 static void smack_release_secctx(char *secdata, u32 seclen)
3471 static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
3473 return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx, ctxlen, 0);
3476 static int smack_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
3478 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SMACK, ctx, ctxlen, 0);
3481 static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
3484 len = smack_inode_getsecurity(inode, XATTR_SMACK_SUFFIX, ctx, true);
3492 struct security_operations smack_ops = {
3495 .ptrace_access_check = smack_ptrace_access_check,
3496 .ptrace_traceme = smack_ptrace_traceme,
3497 .syslog = smack_syslog,
3499 .sb_alloc_security = smack_sb_alloc_security,
3500 .sb_free_security = smack_sb_free_security,
3501 .sb_copy_data = smack_sb_copy_data,
3502 .sb_kern_mount = smack_sb_kern_mount,
3503 .sb_statfs = smack_sb_statfs,
3504 .sb_mount = smack_sb_mount,
3505 .sb_umount = smack_sb_umount,
3507 .bprm_set_creds = smack_bprm_set_creds,
3508 .bprm_committing_creds = smack_bprm_committing_creds,
3509 .bprm_secureexec = smack_bprm_secureexec,
3511 .inode_alloc_security = smack_inode_alloc_security,
3512 .inode_free_security = smack_inode_free_security,
3513 .inode_init_security = smack_inode_init_security,
3514 .inode_link = smack_inode_link,
3515 .inode_unlink = smack_inode_unlink,
3516 .inode_rmdir = smack_inode_rmdir,
3517 .inode_rename = smack_inode_rename,
3518 .inode_permission = smack_inode_permission,
3519 .inode_setattr = smack_inode_setattr,
3520 .inode_getattr = smack_inode_getattr,
3521 .inode_setxattr = smack_inode_setxattr,
3522 .inode_post_setxattr = smack_inode_post_setxattr,
3523 .inode_getxattr = smack_inode_getxattr,
3524 .inode_removexattr = smack_inode_removexattr,
3525 .inode_getsecurity = smack_inode_getsecurity,
3526 .inode_setsecurity = smack_inode_setsecurity,
3527 .inode_listsecurity = smack_inode_listsecurity,
3528 .inode_getsecid = smack_inode_getsecid,
3530 .file_permission = smack_file_permission,
3531 .file_alloc_security = smack_file_alloc_security,
3532 .file_free_security = smack_file_free_security,
3533 .file_ioctl = smack_file_ioctl,
3534 .file_lock = smack_file_lock,
3535 .file_fcntl = smack_file_fcntl,
3536 .file_mmap = smack_file_mmap,
3537 .file_set_fowner = smack_file_set_fowner,
3538 .file_send_sigiotask = smack_file_send_sigiotask,
3539 .file_receive = smack_file_receive,
3541 .dentry_open = smack_dentry_open,
3543 .cred_alloc_blank = smack_cred_alloc_blank,
3544 .cred_free = smack_cred_free,
3545 .cred_prepare = smack_cred_prepare,
3546 .cred_transfer = smack_cred_transfer,
3547 .kernel_act_as = smack_kernel_act_as,
3548 .kernel_create_files_as = smack_kernel_create_files_as,
3549 .task_setpgid = smack_task_setpgid,
3550 .task_getpgid = smack_task_getpgid,
3551 .task_getsid = smack_task_getsid,
3552 .task_getsecid = smack_task_getsecid,
3553 .task_setnice = smack_task_setnice,
3554 .task_setioprio = smack_task_setioprio,
3555 .task_getioprio = smack_task_getioprio,
3556 .task_setscheduler = smack_task_setscheduler,
3557 .task_getscheduler = smack_task_getscheduler,
3558 .task_movememory = smack_task_movememory,
3559 .task_kill = smack_task_kill,
3560 .task_wait = smack_task_wait,
3561 .task_to_inode = smack_task_to_inode,
3563 .ipc_permission = smack_ipc_permission,
3564 .ipc_getsecid = smack_ipc_getsecid,
3566 .msg_msg_alloc_security = smack_msg_msg_alloc_security,
3567 .msg_msg_free_security = smack_msg_msg_free_security,
3569 .msg_queue_alloc_security = smack_msg_queue_alloc_security,
3570 .msg_queue_free_security = smack_msg_queue_free_security,
3571 .msg_queue_associate = smack_msg_queue_associate,
3572 .msg_queue_msgctl = smack_msg_queue_msgctl,
3573 .msg_queue_msgsnd = smack_msg_queue_msgsnd,
3574 .msg_queue_msgrcv = smack_msg_queue_msgrcv,
3576 .shm_alloc_security = smack_shm_alloc_security,
3577 .shm_free_security = smack_shm_free_security,
3578 .shm_associate = smack_shm_associate,
3579 .shm_shmctl = smack_shm_shmctl,
3580 .shm_shmat = smack_shm_shmat,
3582 .sem_alloc_security = smack_sem_alloc_security,
3583 .sem_free_security = smack_sem_free_security,
3584 .sem_associate = smack_sem_associate,
3585 .sem_semctl = smack_sem_semctl,
3586 .sem_semop = smack_sem_semop,
3588 .d_instantiate = smack_d_instantiate,
3590 .getprocattr = smack_getprocattr,
3591 .setprocattr = smack_setprocattr,
3593 .unix_stream_connect = smack_unix_stream_connect,
3594 .unix_may_send = smack_unix_may_send,
3596 .socket_post_create = smack_socket_post_create,
3597 .socket_connect = smack_socket_connect,
3598 .socket_sendmsg = smack_socket_sendmsg,
3599 .socket_sock_rcv_skb = smack_socket_sock_rcv_skb,
3600 .socket_getpeersec_stream = smack_socket_getpeersec_stream,
3601 .socket_getpeersec_dgram = smack_socket_getpeersec_dgram,
3602 .sk_alloc_security = smack_sk_alloc_security,
3603 .sk_free_security = smack_sk_free_security,
3604 .sock_graft = smack_sock_graft,
3605 .inet_conn_request = smack_inet_conn_request,
3606 .inet_csk_clone = smack_inet_csk_clone,
3608 /* key management security hooks */
3610 .key_alloc = smack_key_alloc,
3611 .key_free = smack_key_free,
3612 .key_permission = smack_key_permission,
3613 #endif /* CONFIG_KEYS */
3617 .audit_rule_init = smack_audit_rule_init,
3618 .audit_rule_known = smack_audit_rule_known,
3619 .audit_rule_match = smack_audit_rule_match,
3620 .audit_rule_free = smack_audit_rule_free,
3621 #endif /* CONFIG_AUDIT */
3623 .secid_to_secctx = smack_secid_to_secctx,
3624 .secctx_to_secid = smack_secctx_to_secid,
3625 .release_secctx = smack_release_secctx,
3626 .inode_notifysecctx = smack_inode_notifysecctx,
3627 .inode_setsecctx = smack_inode_setsecctx,
3628 .inode_getsecctx = smack_inode_getsecctx,
3632 static __init void init_smack_know_list(void)
3634 list_add(&smack_known_huh.list, &smack_known_list);
3635 list_add(&smack_known_hat.list, &smack_known_list);
3636 list_add(&smack_known_star.list, &smack_known_list);
3637 list_add(&smack_known_floor.list, &smack_known_list);
3638 list_add(&smack_known_invalid.list, &smack_known_list);
3639 list_add(&smack_known_web.list, &smack_known_list);
3643 * smack_init - initialize the smack system
3647 static __init int smack_init(void)
3650 struct task_smack *tsp;
3652 if (!security_module_enable(&smack_ops))
3655 tsp = new_task_smack(smack_known_floor.smk_known,
3656 smack_known_floor.smk_known, GFP_KERNEL);
3660 printk(KERN_INFO "Smack: Initializing.\n");
3663 * Set the security state for the initial task.
3665 cred = (struct cred *) current->cred;
3666 cred->security = tsp;
3668 /* initialize the smack_know_list */
3669 init_smack_know_list();
3673 spin_lock_init(&smack_known_huh.smk_cipsolock);
3674 spin_lock_init(&smack_known_hat.smk_cipsolock);
3675 spin_lock_init(&smack_known_star.smk_cipsolock);
3676 spin_lock_init(&smack_known_floor.smk_cipsolock);
3677 spin_lock_init(&smack_known_invalid.smk_cipsolock);
3682 if (register_security(&smack_ops))
3683 panic("smack: Unable to register with kernel.\n");
3689 * Smack requires early initialization in order to label
3690 * all processes and objects when they are created.
3692 security_initcall(smack_init);