2 * Simplified MAC Kernel (smack) security module
4 * This file contains the smack hook function implementations.
7 * Casey Schaufler <casey@schaufler-ca.com>
9 * Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com>
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License version 2,
13 * as published by the Free Software Foundation.
16 #include <linux/xattr.h>
17 #include <linux/pagemap.h>
18 #include <linux/mount.h>
19 #include <linux/stat.h>
20 #include <linux/ext2_fs.h>
22 #include <asm/ioctls.h>
23 #include <linux/tcp.h>
24 #include <linux/udp.h>
25 #include <linux/mutex.h>
26 #include <linux/pipe_fs_i.h>
27 #include <net/netlabel.h>
28 #include <net/cipso_ipv4.h>
29 #include <linux/audit.h>
34 * I hope these are the hokeyist lines of code in the module. Casey.
36 #define DEVPTS_SUPER_MAGIC 0x1cd1
37 #define SOCKFS_MAGIC 0x534F434B
38 #define TMPFS_MAGIC 0x01021994
41 * smk_fetch - Fetch the smack label from a file.
42 * @ip: a pointer to the inode
43 * @dp: a pointer to the dentry
45 * Returns a pointer to the master list entry for the Smack label
46 * or NULL if there was no label to fetch.
48 static char *smk_fetch(struct inode *ip, struct dentry *dp)
51 char in[SMK_LABELLEN];
53 if (ip->i_op->getxattr == NULL)
56 rc = ip->i_op->getxattr(dp, XATTR_NAME_SMACK, in, SMK_LABELLEN);
60 return smk_import(in, rc);
64 * new_inode_smack - allocate an inode security blob
65 * @smack: a pointer to the Smack label to use in the blob
67 * Returns the new blob or NULL if there's no memory available
69 struct inode_smack *new_inode_smack(char *smack)
71 struct inode_smack *isp;
73 isp = kzalloc(sizeof(struct inode_smack), GFP_KERNEL);
77 isp->smk_inode = smack;
79 mutex_init(&isp->smk_lock);
90 * smack_ptrace_may_access - Smack approval on PTRACE_ATTACH
91 * @ctp: child task pointer
93 * Returns 0 if access is OK, an error code otherwise
95 * Do the capability checks, and require read and write.
97 static int smack_ptrace_may_access(struct task_struct *ctp, unsigned int mode)
101 rc = cap_ptrace_may_access(ctp, mode);
105 rc = smk_access(current->cred->security, ctp->cred->security,
107 if (rc != 0 && capable(CAP_MAC_OVERRIDE))
113 * smack_ptrace_traceme - Smack approval on PTRACE_TRACEME
114 * @ptp: parent task pointer
116 * Returns 0 if access is OK, an error code otherwise
118 * Do the capability checks, and require read and write.
120 static int smack_ptrace_traceme(struct task_struct *ptp)
124 rc = cap_ptrace_traceme(ptp);
128 rc = smk_access(ptp->cred->security, current->cred->security,
130 if (rc != 0 && has_capability(ptp, CAP_MAC_OVERRIDE))
136 * smack_syslog - Smack approval on syslog
137 * @type: message type
139 * Require that the task has the floor label
141 * Returns 0 on success, error code otherwise.
143 static int smack_syslog(int type)
146 char *sp = current_security();
148 rc = cap_syslog(type);
152 if (capable(CAP_MAC_OVERRIDE))
155 if (sp != smack_known_floor.smk_known)
167 * smack_sb_alloc_security - allocate a superblock blob
168 * @sb: the superblock getting the blob
170 * Returns 0 on success or -ENOMEM on error.
172 static int smack_sb_alloc_security(struct super_block *sb)
174 struct superblock_smack *sbsp;
176 sbsp = kzalloc(sizeof(struct superblock_smack), GFP_KERNEL);
181 sbsp->smk_root = smack_known_floor.smk_known;
182 sbsp->smk_default = smack_known_floor.smk_known;
183 sbsp->smk_floor = smack_known_floor.smk_known;
184 sbsp->smk_hat = smack_known_hat.smk_known;
185 sbsp->smk_initialized = 0;
186 spin_lock_init(&sbsp->smk_sblock);
188 sb->s_security = sbsp;
194 * smack_sb_free_security - free a superblock blob
195 * @sb: the superblock getting the blob
198 static void smack_sb_free_security(struct super_block *sb)
200 kfree(sb->s_security);
201 sb->s_security = NULL;
205 * smack_sb_copy_data - copy mount options data for processing
206 * @type: file system type
207 * @orig: where to start
210 * Returns 0 on success or -ENOMEM on error.
212 * Copy the Smack specific mount options out of the mount
215 static int smack_sb_copy_data(char *orig, char *smackopts)
217 char *cp, *commap, *otheropts, *dp;
219 otheropts = (char *)get_zeroed_page(GFP_KERNEL);
220 if (otheropts == NULL)
223 for (cp = orig, commap = orig; commap != NULL; cp = commap + 1) {
224 if (strstr(cp, SMK_FSDEFAULT) == cp)
226 else if (strstr(cp, SMK_FSFLOOR) == cp)
228 else if (strstr(cp, SMK_FSHAT) == cp)
230 else if (strstr(cp, SMK_FSROOT) == cp)
235 commap = strchr(cp, ',');
244 strcpy(orig, otheropts);
245 free_page((unsigned long)otheropts);
251 * smack_sb_kern_mount - Smack specific mount processing
252 * @sb: the file system superblock
253 * @data: the smack mount options
255 * Returns 0 on success, an error code on failure
257 static int smack_sb_kern_mount(struct super_block *sb, void *data)
259 struct dentry *root = sb->s_root;
260 struct inode *inode = root->d_inode;
261 struct superblock_smack *sp = sb->s_security;
262 struct inode_smack *isp;
267 spin_lock(&sp->smk_sblock);
268 if (sp->smk_initialized != 0) {
269 spin_unlock(&sp->smk_sblock);
272 sp->smk_initialized = 1;
273 spin_unlock(&sp->smk_sblock);
275 for (op = data; op != NULL; op = commap) {
276 commap = strchr(op, ',');
280 if (strncmp(op, SMK_FSHAT, strlen(SMK_FSHAT)) == 0) {
281 op += strlen(SMK_FSHAT);
282 nsp = smk_import(op, 0);
285 } else if (strncmp(op, SMK_FSFLOOR, strlen(SMK_FSFLOOR)) == 0) {
286 op += strlen(SMK_FSFLOOR);
287 nsp = smk_import(op, 0);
290 } else if (strncmp(op, SMK_FSDEFAULT,
291 strlen(SMK_FSDEFAULT)) == 0) {
292 op += strlen(SMK_FSDEFAULT);
293 nsp = smk_import(op, 0);
295 sp->smk_default = nsp;
296 } else if (strncmp(op, SMK_FSROOT, strlen(SMK_FSROOT)) == 0) {
297 op += strlen(SMK_FSROOT);
298 nsp = smk_import(op, 0);
305 * Initialize the root inode.
307 isp = inode->i_security;
309 inode->i_security = new_inode_smack(sp->smk_root);
311 isp->smk_inode = sp->smk_root;
317 * smack_sb_statfs - Smack check on statfs
318 * @dentry: identifies the file system in question
320 * Returns 0 if current can read the floor of the filesystem,
321 * and error code otherwise
323 static int smack_sb_statfs(struct dentry *dentry)
325 struct superblock_smack *sbp = dentry->d_sb->s_security;
327 return smk_curacc(sbp->smk_floor, MAY_READ);
331 * smack_sb_mount - Smack check for mounting
338 * Returns 0 if current can write the floor of the filesystem
339 * being mounted on, an error code otherwise.
341 static int smack_sb_mount(char *dev_name, struct path *path,
342 char *type, unsigned long flags, void *data)
344 struct superblock_smack *sbp = path->mnt->mnt_sb->s_security;
346 return smk_curacc(sbp->smk_floor, MAY_WRITE);
350 * smack_sb_umount - Smack check for unmounting
351 * @mnt: file system to unmount
354 * Returns 0 if current can write the floor of the filesystem
355 * being unmounted, an error code otherwise.
357 static int smack_sb_umount(struct vfsmount *mnt, int flags)
359 struct superblock_smack *sbp;
361 sbp = mnt->mnt_sb->s_security;
363 return smk_curacc(sbp->smk_floor, MAY_WRITE);
371 * smack_inode_alloc_security - allocate an inode blob
372 * @inode - the inode in need of a blob
374 * Returns 0 if it gets a blob, -ENOMEM otherwise
376 static int smack_inode_alloc_security(struct inode *inode)
378 inode->i_security = new_inode_smack(current_security());
379 if (inode->i_security == NULL)
385 * smack_inode_free_security - free an inode blob
386 * @inode - the inode with a blob
388 * Clears the blob pointer in inode
390 static void smack_inode_free_security(struct inode *inode)
392 kfree(inode->i_security);
393 inode->i_security = NULL;
397 * smack_inode_init_security - copy out the smack from an inode
400 * @name: where to put the attribute name
401 * @value: where to put the attribute value
402 * @len: where to put the length of the attribute
404 * Returns 0 if it all works out, -ENOMEM if there's no memory
406 static int smack_inode_init_security(struct inode *inode, struct inode *dir,
407 char **name, void **value, size_t *len)
409 char *isp = smk_of_inode(inode);
412 *name = kstrdup(XATTR_SMACK_SUFFIX, GFP_KERNEL);
418 *value = kstrdup(isp, GFP_KERNEL);
424 *len = strlen(isp) + 1;
430 * smack_inode_link - Smack check on link
431 * @old_dentry: the existing object
433 * @new_dentry: the new object
435 * Returns 0 if access is permitted, an error code otherwise
437 static int smack_inode_link(struct dentry *old_dentry, struct inode *dir,
438 struct dentry *new_dentry)
443 isp = smk_of_inode(old_dentry->d_inode);
444 rc = smk_curacc(isp, MAY_WRITE);
446 if (rc == 0 && new_dentry->d_inode != NULL) {
447 isp = smk_of_inode(new_dentry->d_inode);
448 rc = smk_curacc(isp, MAY_WRITE);
455 * smack_inode_unlink - Smack check on inode deletion
456 * @dir: containing directory object
457 * @dentry: file to unlink
459 * Returns 0 if current can write the containing directory
460 * and the object, error code otherwise
462 static int smack_inode_unlink(struct inode *dir, struct dentry *dentry)
464 struct inode *ip = dentry->d_inode;
468 * You need write access to the thing you're unlinking
470 rc = smk_curacc(smk_of_inode(ip), MAY_WRITE);
473 * You also need write access to the containing directory
475 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE);
481 * smack_inode_rmdir - Smack check on directory deletion
482 * @dir: containing directory object
483 * @dentry: directory to unlink
485 * Returns 0 if current can write the containing directory
486 * and the directory, error code otherwise
488 static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry)
493 * You need write access to the thing you're removing
495 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE);
498 * You also need write access to the containing directory
500 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE);
506 * smack_inode_rename - Smack check on rename
507 * @old_inode: the old directory
508 * @old_dentry: unused
509 * @new_inode: the new directory
510 * @new_dentry: unused
512 * Read and write access is required on both the old and
515 * Returns 0 if access is permitted, an error code otherwise
517 static int smack_inode_rename(struct inode *old_inode,
518 struct dentry *old_dentry,
519 struct inode *new_inode,
520 struct dentry *new_dentry)
525 isp = smk_of_inode(old_dentry->d_inode);
526 rc = smk_curacc(isp, MAY_READWRITE);
528 if (rc == 0 && new_dentry->d_inode != NULL) {
529 isp = smk_of_inode(new_dentry->d_inode);
530 rc = smk_curacc(isp, MAY_READWRITE);
537 * smack_inode_permission - Smack version of permission()
538 * @inode: the inode in question
539 * @mask: the access requested
542 * This is the important Smack hook.
544 * Returns 0 if access is permitted, -EACCES otherwise
546 static int smack_inode_permission(struct inode *inode, int mask)
549 * No permission to check. Existence test. Yup, it's there.
554 return smk_curacc(smk_of_inode(inode), mask);
558 * smack_inode_setattr - Smack check for setting attributes
559 * @dentry: the object
560 * @iattr: for the force flag
562 * Returns 0 if access is permitted, an error code otherwise
564 static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr)
567 * Need to allow for clearing the setuid bit.
569 if (iattr->ia_valid & ATTR_FORCE)
572 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE);
576 * smack_inode_getattr - Smack check for getting attributes
578 * @dentry: the object
580 * Returns 0 if access is permitted, an error code otherwise
582 static int smack_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
584 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ);
588 * smack_inode_setxattr - Smack check for setting xattrs
589 * @dentry: the object
590 * @name: name of the attribute
595 * This protects the Smack attribute explicitly.
597 * Returns 0 if access is permitted, an error code otherwise
599 static int smack_inode_setxattr(struct dentry *dentry, const char *name,
600 const void *value, size_t size, int flags)
604 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
605 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
606 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) {
607 if (!capable(CAP_MAC_ADMIN))
610 rc = cap_inode_setxattr(dentry, name, value, size, flags);
613 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE);
619 * smack_inode_post_setxattr - Apply the Smack update approved above
621 * @name: attribute name
622 * @value: attribute value
623 * @size: attribute size
626 * Set the pointer in the inode blob to the entry found
627 * in the master label list.
629 static void smack_inode_post_setxattr(struct dentry *dentry, const char *name,
630 const void *value, size_t size, int flags)
632 struct inode_smack *isp;
638 if (strcmp(name, XATTR_NAME_SMACK))
641 if (size >= SMK_LABELLEN)
644 isp = dentry->d_inode->i_security;
647 * No locking is done here. This is a pointer
650 nsp = smk_import(value, size);
652 isp->smk_inode = nsp;
654 isp->smk_inode = smack_known_invalid.smk_known;
660 * smack_inode_getxattr - Smack check on getxattr
661 * @dentry: the object
664 * Returns 0 if access is permitted, an error code otherwise
666 static int smack_inode_getxattr(struct dentry *dentry, const char *name)
668 return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ);
672 * smack_inode_removexattr - Smack check on removexattr
673 * @dentry: the object
674 * @name: name of the attribute
676 * Removing the Smack attribute requires CAP_MAC_ADMIN
678 * Returns 0 if access is permitted, an error code otherwise
680 static int smack_inode_removexattr(struct dentry *dentry, const char *name)
684 if (strcmp(name, XATTR_NAME_SMACK) == 0 ||
685 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 ||
686 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) {
687 if (!capable(CAP_MAC_ADMIN))
690 rc = cap_inode_removexattr(dentry, name);
693 rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE);
699 * smack_inode_getsecurity - get smack xattrs
701 * @name: attribute name
702 * @buffer: where to put the result
703 * @size: size of the buffer
706 * Returns the size of the attribute or an error code
708 static int smack_inode_getsecurity(const struct inode *inode,
709 const char *name, void **buffer,
712 struct socket_smack *ssp;
714 struct super_block *sbp;
715 struct inode *ip = (struct inode *)inode;
720 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
721 isp = smk_of_inode(inode);
722 ilen = strlen(isp) + 1;
728 * The rest of the Smack xattrs are only on sockets.
731 if (sbp->s_magic != SOCKFS_MAGIC)
735 if (sock == NULL || sock->sk == NULL)
738 ssp = sock->sk->sk_security;
740 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
742 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0)
747 ilen = strlen(isp) + 1;
758 * smack_inode_listsecurity - list the Smack attributes
760 * @buffer: where they go
761 * @buffer_size: size of buffer
763 * Returns 0 on success, -EINVAL otherwise
765 static int smack_inode_listsecurity(struct inode *inode, char *buffer,
768 int len = strlen(XATTR_NAME_SMACK);
770 if (buffer != NULL && len <= buffer_size) {
771 memcpy(buffer, XATTR_NAME_SMACK, len);
778 * smack_inode_getsecid - Extract inode's security id
779 * @inode: inode to extract the info from
780 * @secid: where result will be saved
782 static void smack_inode_getsecid(const struct inode *inode, u32 *secid)
784 struct inode_smack *isp = inode->i_security;
786 *secid = smack_to_secid(isp->smk_inode);
794 * smack_file_permission - Smack check on file operations
800 * Should access checks be done on each read or write?
801 * UNICOS and SELinux say yes.
802 * Trusted Solaris, Trusted Irix, and just about everyone else says no.
804 * I'll say no for now. Smack does not do the frequent
805 * label changing that SELinux does.
807 static int smack_file_permission(struct file *file, int mask)
813 * smack_file_alloc_security - assign a file security blob
816 * The security blob for a file is a pointer to the master
817 * label list, so no allocation is done.
821 static int smack_file_alloc_security(struct file *file)
823 file->f_security = current_security();
828 * smack_file_free_security - clear a file security blob
831 * The security blob for a file is a pointer to the master
832 * label list, so no memory is freed.
834 static void smack_file_free_security(struct file *file)
836 file->f_security = NULL;
840 * smack_file_ioctl - Smack check on ioctls
845 * Relies heavily on the correct use of the ioctl command conventions.
847 * Returns 0 if allowed, error code otherwise
849 static int smack_file_ioctl(struct file *file, unsigned int cmd,
854 if (_IOC_DIR(cmd) & _IOC_WRITE)
855 rc = smk_curacc(file->f_security, MAY_WRITE);
857 if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ))
858 rc = smk_curacc(file->f_security, MAY_READ);
864 * smack_file_lock - Smack check on file locking
868 * Returns 0 if current has write access, error code otherwise
870 static int smack_file_lock(struct file *file, unsigned int cmd)
872 return smk_curacc(file->f_security, MAY_WRITE);
876 * smack_file_fcntl - Smack check on fcntl
878 * @cmd: what action to check
881 * Returns 0 if current has access, error code otherwise
883 static int smack_file_fcntl(struct file *file, unsigned int cmd,
895 rc = smk_curacc(file->f_security, MAY_READ);
903 rc = smk_curacc(file->f_security, MAY_WRITE);
906 rc = smk_curacc(file->f_security, MAY_READWRITE);
913 * smack_file_set_fowner - set the file security blob value
914 * @file: object in question
917 * Further research may be required on this one.
919 static int smack_file_set_fowner(struct file *file)
921 file->f_security = current_security();
926 * smack_file_send_sigiotask - Smack on sigio
927 * @tsk: The target task
928 * @fown: the object the signal come from
931 * Allow a privileged task to get signals even if it shouldn't
933 * Returns 0 if a subject with the object's smack could
934 * write to the task, an error code otherwise.
936 static int smack_file_send_sigiotask(struct task_struct *tsk,
937 struct fown_struct *fown, int signum)
943 * struct fown_struct is never outside the context of a struct file
945 file = container_of(fown, struct file, f_owner);
946 rc = smk_access(file->f_security, tsk->cred->security, MAY_WRITE);
947 if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE))
953 * smack_file_receive - Smack file receive check
956 * Returns 0 if current has access, error code otherwise
958 static int smack_file_receive(struct file *file)
963 * This code relies on bitmasks.
965 if (file->f_mode & FMODE_READ)
967 if (file->f_mode & FMODE_WRITE)
970 return smk_curacc(file->f_security, may);
978 * smack_cred_alloc_security - "allocate" a task cred blob
979 * @cred: the task creds in need of a blob
981 * Smack isn't using copies of blobs. Everyone
982 * points to an immutable list. No alloc required.
983 * No data copy required.
987 static int smack_cred_alloc_security(struct cred *cred)
989 cred->security = current_security();
994 * smack_cred_free - "free" task-level security credentials
995 * @cred: the credentials in question
997 * Smack isn't using copies of blobs. Everyone
998 * points to an immutable list. The blobs never go away.
999 * There is no leak here.
1001 static void smack_cred_free(struct cred *cred)
1003 cred->security = NULL;
1007 * smack_task_setpgid - Smack check on setting pgid
1008 * @p: the task object
1011 * Return 0 if write access is permitted
1013 static int smack_task_setpgid(struct task_struct *p, pid_t pgid)
1015 return smk_curacc(p->cred->security, MAY_WRITE);
1019 * smack_task_getpgid - Smack access check for getpgid
1020 * @p: the object task
1022 * Returns 0 if current can read the object task, error code otherwise
1024 static int smack_task_getpgid(struct task_struct *p)
1026 return smk_curacc(p->cred->security, MAY_READ);
1030 * smack_task_getsid - Smack access check for getsid
1031 * @p: the object task
1033 * Returns 0 if current can read the object task, error code otherwise
1035 static int smack_task_getsid(struct task_struct *p)
1037 return smk_curacc(p->cred->security, MAY_READ);
1041 * smack_task_getsecid - get the secid of the task
1042 * @p: the object task
1043 * @secid: where to put the result
1045 * Sets the secid to contain a u32 version of the smack label.
1047 static void smack_task_getsecid(struct task_struct *p, u32 *secid)
1049 *secid = smack_to_secid(p->cred->security);
1053 * smack_task_setnice - Smack check on setting nice
1054 * @p: the task object
1057 * Return 0 if write access is permitted
1059 static int smack_task_setnice(struct task_struct *p, int nice)
1063 rc = cap_task_setnice(p, nice);
1065 rc = smk_curacc(p->cred->security, MAY_WRITE);
1070 * smack_task_setioprio - Smack check on setting ioprio
1071 * @p: the task object
1074 * Return 0 if write access is permitted
1076 static int smack_task_setioprio(struct task_struct *p, int ioprio)
1080 rc = cap_task_setioprio(p, ioprio);
1082 rc = smk_curacc(p->cred->security, MAY_WRITE);
1087 * smack_task_getioprio - Smack check on reading ioprio
1088 * @p: the task object
1090 * Return 0 if read access is permitted
1092 static int smack_task_getioprio(struct task_struct *p)
1094 return smk_curacc(p->cred->security, MAY_READ);
1098 * smack_task_setscheduler - Smack check on setting scheduler
1099 * @p: the task object
1103 * Return 0 if read access is permitted
1105 static int smack_task_setscheduler(struct task_struct *p, int policy,
1106 struct sched_param *lp)
1110 rc = cap_task_setscheduler(p, policy, lp);
1112 rc = smk_curacc(p->cred->security, MAY_WRITE);
1117 * smack_task_getscheduler - Smack check on reading scheduler
1118 * @p: the task object
1120 * Return 0 if read access is permitted
1122 static int smack_task_getscheduler(struct task_struct *p)
1124 return smk_curacc(p->cred->security, MAY_READ);
1128 * smack_task_movememory - Smack check on moving memory
1129 * @p: the task object
1131 * Return 0 if write access is permitted
1133 static int smack_task_movememory(struct task_struct *p)
1135 return smk_curacc(p->cred->security, MAY_WRITE);
1139 * smack_task_kill - Smack check on signal delivery
1140 * @p: the task object
1143 * @secid: identifies the smack to use in lieu of current's
1145 * Return 0 if write access is permitted
1147 * The secid behavior is an artifact of an SELinux hack
1148 * in the USB code. Someday it may go away.
1150 static int smack_task_kill(struct task_struct *p, struct siginfo *info,
1154 * Sending a signal requires that the sender
1155 * can write the receiver.
1158 return smk_curacc(p->cred->security, MAY_WRITE);
1160 * If the secid isn't 0 we're dealing with some USB IO
1161 * specific behavior. This is not clean. For one thing
1162 * we can't take privilege into account.
1164 return smk_access(smack_from_secid(secid), p->cred->security, MAY_WRITE);
1168 * smack_task_wait - Smack access check for waiting
1169 * @p: task to wait for
1171 * Returns 0 if current can wait for p, error code otherwise
1173 static int smack_task_wait(struct task_struct *p)
1177 rc = smk_access(current->cred->security, p->cred->security, MAY_WRITE);
1182 * Allow the operation to succeed if either task
1183 * has privilege to perform operations that might
1184 * account for the smack labels having gotten to
1185 * be different in the first place.
1187 * This breaks the strict subject/object access
1188 * control ideal, taking the object's privilege
1189 * state into account in the decision as well as
1192 if (capable(CAP_MAC_OVERRIDE) || has_capability(p, CAP_MAC_OVERRIDE))
1199 * smack_task_to_inode - copy task smack into the inode blob
1200 * @p: task to copy from
1201 * inode: inode to copy to
1203 * Sets the smack pointer in the inode security blob
1205 static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
1207 struct inode_smack *isp = inode->i_security;
1208 isp->smk_inode = p->cred->security;
1216 * smack_sk_alloc_security - Allocate a socket blob
1219 * @priority: memory allocation priority
1221 * Assign Smack pointers to current
1223 * Returns 0 on success, -ENOMEM is there's no memory
1225 static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags)
1227 char *csp = current_security();
1228 struct socket_smack *ssp;
1230 ssp = kzalloc(sizeof(struct socket_smack), gfp_flags);
1236 ssp->smk_packet[0] = '\0';
1238 sk->sk_security = ssp;
1244 * smack_sk_free_security - Free a socket blob
1247 * Clears the blob pointer
1249 static void smack_sk_free_security(struct sock *sk)
1251 kfree(sk->sk_security);
1255 * smack_set_catset - convert a capset to netlabel mls categories
1256 * @catset: the Smack categories
1257 * @sap: where to put the netlabel categories
1259 * Allocates and fills attr.mls.cat
1261 static void smack_set_catset(char *catset, struct netlbl_lsm_secattr *sap)
1272 sap->flags |= NETLBL_SECATTR_MLS_CAT;
1273 sap->attr.mls.cat = netlbl_secattr_catmap_alloc(GFP_ATOMIC);
1274 sap->attr.mls.cat->startbit = 0;
1276 for (cat = 1, cp = catset, byte = 0; byte < SMK_LABELLEN; cp++, byte++)
1277 for (m = 0x80; m != 0; m >>= 1, cat++) {
1280 rc = netlbl_secattr_catmap_setbit(sap->attr.mls.cat,
1286 * smack_to_secattr - fill a secattr from a smack value
1287 * @smack: the smack value
1288 * @nlsp: where the result goes
1290 * Casey says that CIPSO is good enough for now.
1291 * It can be used to effect.
1292 * It can also be abused to effect when necessary.
1293 * Appologies to the TSIG group in general and GW in particular.
1295 static void smack_to_secattr(char *smack, struct netlbl_lsm_secattr *nlsp)
1297 struct smack_cipso cipso;
1300 switch (smack_net_nltype) {
1301 case NETLBL_NLTYPE_CIPSOV4:
1302 nlsp->domain = smack;
1303 nlsp->flags = NETLBL_SECATTR_DOMAIN | NETLBL_SECATTR_MLS_LVL;
1305 rc = smack_to_cipso(smack, &cipso);
1307 nlsp->attr.mls.lvl = cipso.smk_level;
1308 smack_set_catset(cipso.smk_catset, nlsp);
1310 nlsp->attr.mls.lvl = smack_cipso_direct;
1311 smack_set_catset(smack, nlsp);
1320 * smack_netlabel - Set the secattr on a socket
1323 * Convert the outbound smack value (smk_out) to a
1324 * secattr and attach it to the socket.
1326 * Returns 0 on success or an error code
1328 static int smack_netlabel(struct sock *sk)
1330 struct socket_smack *ssp;
1331 struct netlbl_lsm_secattr secattr;
1334 ssp = sk->sk_security;
1335 netlbl_secattr_init(&secattr);
1336 smack_to_secattr(ssp->smk_out, &secattr);
1337 rc = netlbl_sock_setattr(sk, &secattr);
1338 netlbl_secattr_destroy(&secattr);
1344 * smack_inode_setsecurity - set smack xattrs
1345 * @inode: the object
1346 * @name: attribute name
1347 * @value: attribute value
1348 * @size: size of the attribute
1351 * Sets the named attribute in the appropriate blob
1353 * Returns 0 on success, or an error code
1355 static int smack_inode_setsecurity(struct inode *inode, const char *name,
1356 const void *value, size_t size, int flags)
1359 struct inode_smack *nsp = inode->i_security;
1360 struct socket_smack *ssp;
1361 struct socket *sock;
1364 if (value == NULL || size > SMK_LABELLEN)
1367 sp = smk_import(value, size);
1371 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) {
1372 nsp->smk_inode = sp;
1376 * The rest of the Smack xattrs are only on sockets.
1378 if (inode->i_sb->s_magic != SOCKFS_MAGIC)
1381 sock = SOCKET_I(inode);
1382 if (sock == NULL || sock->sk == NULL)
1385 ssp = sock->sk->sk_security;
1387 if (strcmp(name, XATTR_SMACK_IPIN) == 0)
1389 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) {
1391 rc = smack_netlabel(sock->sk);
1393 printk(KERN_WARNING "Smack: \"%s\" netlbl error %d.\n",
1402 * smack_socket_post_create - finish socket setup
1404 * @family: protocol family
1409 * Sets the netlabel information on the socket
1411 * Returns 0 on success, and error code otherwise
1413 static int smack_socket_post_create(struct socket *sock, int family,
1414 int type, int protocol, int kern)
1416 if (family != PF_INET || sock->sk == NULL)
1419 * Set the outbound netlbl.
1421 return smack_netlabel(sock->sk);
1425 * smack_flags_to_may - convert S_ to MAY_ values
1426 * @flags: the S_ value
1428 * Returns the equivalent MAY_ value
1430 static int smack_flags_to_may(int flags)
1434 if (flags & S_IRUGO)
1436 if (flags & S_IWUGO)
1438 if (flags & S_IXUGO)
1445 * smack_msg_msg_alloc_security - Set the security blob for msg_msg
1450 static int smack_msg_msg_alloc_security(struct msg_msg *msg)
1452 msg->security = current_security();
1457 * smack_msg_msg_free_security - Clear the security blob for msg_msg
1460 * Clears the blob pointer
1462 static void smack_msg_msg_free_security(struct msg_msg *msg)
1464 msg->security = NULL;
1468 * smack_of_shm - the smack pointer for the shm
1471 * Returns a pointer to the smack value
1473 static char *smack_of_shm(struct shmid_kernel *shp)
1475 return (char *)shp->shm_perm.security;
1479 * smack_shm_alloc_security - Set the security blob for shm
1484 static int smack_shm_alloc_security(struct shmid_kernel *shp)
1486 struct kern_ipc_perm *isp = &shp->shm_perm;
1488 isp->security = current_security();
1493 * smack_shm_free_security - Clear the security blob for shm
1496 * Clears the blob pointer
1498 static void smack_shm_free_security(struct shmid_kernel *shp)
1500 struct kern_ipc_perm *isp = &shp->shm_perm;
1502 isp->security = NULL;
1506 * smack_shm_associate - Smack access check for shm
1508 * @shmflg: access requested
1510 * Returns 0 if current has the requested access, error code otherwise
1512 static int smack_shm_associate(struct shmid_kernel *shp, int shmflg)
1514 char *ssp = smack_of_shm(shp);
1517 may = smack_flags_to_may(shmflg);
1518 return smk_curacc(ssp, may);
1522 * smack_shm_shmctl - Smack access check for shm
1524 * @cmd: what it wants to do
1526 * Returns 0 if current has the requested access, error code otherwise
1528 static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd)
1542 may = MAY_READWRITE;
1547 * System level information.
1554 ssp = smack_of_shm(shp);
1555 return smk_curacc(ssp, may);
1559 * smack_shm_shmat - Smack access for shmat
1562 * @shmflg: access requested
1564 * Returns 0 if current has the requested access, error code otherwise
1566 static int smack_shm_shmat(struct shmid_kernel *shp, char __user *shmaddr,
1569 char *ssp = smack_of_shm(shp);
1572 may = smack_flags_to_may(shmflg);
1573 return smk_curacc(ssp, may);
1577 * smack_of_sem - the smack pointer for the sem
1580 * Returns a pointer to the smack value
1582 static char *smack_of_sem(struct sem_array *sma)
1584 return (char *)sma->sem_perm.security;
1588 * smack_sem_alloc_security - Set the security blob for sem
1593 static int smack_sem_alloc_security(struct sem_array *sma)
1595 struct kern_ipc_perm *isp = &sma->sem_perm;
1597 isp->security = current_security();
1602 * smack_sem_free_security - Clear the security blob for sem
1605 * Clears the blob pointer
1607 static void smack_sem_free_security(struct sem_array *sma)
1609 struct kern_ipc_perm *isp = &sma->sem_perm;
1611 isp->security = NULL;
1615 * smack_sem_associate - Smack access check for sem
1617 * @semflg: access requested
1619 * Returns 0 if current has the requested access, error code otherwise
1621 static int smack_sem_associate(struct sem_array *sma, int semflg)
1623 char *ssp = smack_of_sem(sma);
1626 may = smack_flags_to_may(semflg);
1627 return smk_curacc(ssp, may);
1631 * smack_sem_shmctl - Smack access check for sem
1633 * @cmd: what it wants to do
1635 * Returns 0 if current has the requested access, error code otherwise
1637 static int smack_sem_semctl(struct sem_array *sma, int cmd)
1656 may = MAY_READWRITE;
1661 * System level information
1668 ssp = smack_of_sem(sma);
1669 return smk_curacc(ssp, may);
1673 * smack_sem_semop - Smack checks of semaphore operations
1679 * Treated as read and write in all cases.
1681 * Returns 0 if access is allowed, error code otherwise
1683 static int smack_sem_semop(struct sem_array *sma, struct sembuf *sops,
1684 unsigned nsops, int alter)
1686 char *ssp = smack_of_sem(sma);
1688 return smk_curacc(ssp, MAY_READWRITE);
1692 * smack_msg_alloc_security - Set the security blob for msg
1697 static int smack_msg_queue_alloc_security(struct msg_queue *msq)
1699 struct kern_ipc_perm *kisp = &msq->q_perm;
1701 kisp->security = current_security();
1706 * smack_msg_free_security - Clear the security blob for msg
1709 * Clears the blob pointer
1711 static void smack_msg_queue_free_security(struct msg_queue *msq)
1713 struct kern_ipc_perm *kisp = &msq->q_perm;
1715 kisp->security = NULL;
1719 * smack_of_msq - the smack pointer for the msq
1722 * Returns a pointer to the smack value
1724 static char *smack_of_msq(struct msg_queue *msq)
1726 return (char *)msq->q_perm.security;
1730 * smack_msg_queue_associate - Smack access check for msg_queue
1732 * @msqflg: access requested
1734 * Returns 0 if current has the requested access, error code otherwise
1736 static int smack_msg_queue_associate(struct msg_queue *msq, int msqflg)
1738 char *msp = smack_of_msq(msq);
1741 may = smack_flags_to_may(msqflg);
1742 return smk_curacc(msp, may);
1746 * smack_msg_queue_msgctl - Smack access check for msg_queue
1748 * @cmd: what it wants to do
1750 * Returns 0 if current has the requested access, error code otherwise
1752 static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd)
1764 may = MAY_READWRITE;
1769 * System level information
1776 msp = smack_of_msq(msq);
1777 return smk_curacc(msp, may);
1781 * smack_msg_queue_msgsnd - Smack access check for msg_queue
1784 * @msqflg: access requested
1786 * Returns 0 if current has the requested access, error code otherwise
1788 static int smack_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg,
1791 char *msp = smack_of_msq(msq);
1794 rc = smack_flags_to_may(msqflg);
1795 return smk_curacc(msp, rc);
1799 * smack_msg_queue_msgsnd - Smack access check for msg_queue
1806 * Returns 0 if current has read and write access, error code otherwise
1808 static int smack_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
1809 struct task_struct *target, long type, int mode)
1811 char *msp = smack_of_msq(msq);
1813 return smk_curacc(msp, MAY_READWRITE);
1817 * smack_ipc_permission - Smack access for ipc_permission()
1818 * @ipp: the object permissions
1819 * @flag: access requested
1821 * Returns 0 if current has read and write access, error code otherwise
1823 static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag)
1825 char *isp = ipp->security;
1828 may = smack_flags_to_may(flag);
1829 return smk_curacc(isp, may);
1833 * smack_ipc_getsecid - Extract smack security id
1834 * @ipcp: the object permissions
1835 * @secid: where result will be saved
1837 static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid)
1839 char *smack = ipp->security;
1841 *secid = smack_to_secid(smack);
1845 * smack_d_instantiate - Make sure the blob is correct on an inode
1846 * @opt_dentry: unused
1847 * @inode: the object
1849 * Set the inode's security blob if it hasn't been done already.
1851 static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
1853 struct super_block *sbp;
1854 struct superblock_smack *sbsp;
1855 struct inode_smack *isp;
1856 char *csp = current_security();
1864 isp = inode->i_security;
1866 mutex_lock(&isp->smk_lock);
1868 * If the inode is already instantiated
1869 * take the quick way out
1871 if (isp->smk_flags & SMK_INODE_INSTANT)
1875 sbsp = sbp->s_security;
1877 * We're going to use the superblock default label
1878 * if there's no label on the file.
1880 final = sbsp->smk_default;
1883 * If this is the root inode the superblock
1884 * may be in the process of initialization.
1885 * If that is the case use the root value out
1886 * of the superblock.
1888 if (opt_dentry->d_parent == opt_dentry) {
1889 isp->smk_inode = sbsp->smk_root;
1890 isp->smk_flags |= SMK_INODE_INSTANT;
1895 * This is pretty hackish.
1896 * Casey says that we shouldn't have to do
1897 * file system specific code, but it does help
1898 * with keeping it simple.
1900 switch (sbp->s_magic) {
1903 * Casey says that it's a little embarassing
1904 * that the smack file system doesn't do
1905 * extended attributes.
1907 final = smack_known_star.smk_known;
1911 * Casey says pipes are easy (?)
1913 final = smack_known_star.smk_known;
1915 case DEVPTS_SUPER_MAGIC:
1917 * devpts seems content with the label of the task.
1918 * Programs that change smack have to treat the
1925 * Casey says sockets get the smack of the task.
1929 case PROC_SUPER_MAGIC:
1931 * Casey says procfs appears not to care.
1932 * The superblock default suffices.
1937 * Device labels should come from the filesystem,
1938 * but watch out, because they're volitile,
1939 * getting recreated on every reboot.
1941 final = smack_known_star.smk_known;
1945 * If a smack value has been set we want to use it,
1946 * but since tmpfs isn't giving us the opportunity
1947 * to set mount options simulate setting the
1948 * superblock default.
1952 * This isn't an understood special case.
1953 * Get the value from the xattr.
1955 * No xattr support means, alas, no SMACK label.
1956 * Use the aforeapplied default.
1957 * It would be curious if the label of the task
1958 * does not match that assigned.
1960 if (inode->i_op->getxattr == NULL)
1963 * Get the dentry for xattr.
1965 if (opt_dentry == NULL) {
1966 dp = d_find_alias(inode);
1970 dp = dget(opt_dentry);
1975 fetched = smk_fetch(inode, dp);
1976 if (fetched != NULL)
1984 isp->smk_inode = csp;
1986 isp->smk_inode = final;
1988 isp->smk_flags |= SMK_INODE_INSTANT;
1991 mutex_unlock(&isp->smk_lock);
1996 * smack_getprocattr - Smack process attribute access
1997 * @p: the object task
1998 * @name: the name of the attribute in /proc/.../attr
1999 * @value: where to put the result
2001 * Places a copy of the task Smack into value
2003 * Returns the length of the smack label or an error code
2005 static int smack_getprocattr(struct task_struct *p, char *name, char **value)
2010 if (strcmp(name, "current") != 0)
2013 cp = kstrdup(p->cred->security, GFP_KERNEL);
2023 * smack_setprocattr - Smack process attribute setting
2024 * @p: the object task
2025 * @name: the name of the attribute in /proc/.../attr
2026 * @value: the value to set
2027 * @size: the size of the value
2029 * Sets the Smack value of the task. Only setting self
2030 * is permitted and only with privilege
2032 * Returns the length of the smack label or an error code
2034 static int smack_setprocattr(struct task_struct *p, char *name,
2035 void *value, size_t size)
2040 * Changing another process' Smack value is too dangerous
2041 * and supports no sane use case.
2046 if (!capable(CAP_MAC_ADMIN))
2049 if (value == NULL || size == 0 || size >= SMK_LABELLEN)
2052 if (strcmp(name, "current") != 0)
2055 newsmack = smk_import(value, size);
2056 if (newsmack == NULL)
2059 p->cred->security = newsmack;
2064 * smack_unix_stream_connect - Smack access on UDS
2066 * @other: the other socket
2069 * Return 0 if a subject with the smack of sock could access
2070 * an object with the smack of other, otherwise an error code
2072 static int smack_unix_stream_connect(struct socket *sock,
2073 struct socket *other, struct sock *newsk)
2075 struct inode *sp = SOCK_INODE(sock);
2076 struct inode *op = SOCK_INODE(other);
2078 return smk_access(smk_of_inode(sp), smk_of_inode(op), MAY_READWRITE);
2082 * smack_unix_may_send - Smack access on UDS
2084 * @other: the other socket
2086 * Return 0 if a subject with the smack of sock could access
2087 * an object with the smack of other, otherwise an error code
2089 static int smack_unix_may_send(struct socket *sock, struct socket *other)
2091 struct inode *sp = SOCK_INODE(sock);
2092 struct inode *op = SOCK_INODE(other);
2094 return smk_access(smk_of_inode(sp), smk_of_inode(op), MAY_WRITE);
2098 * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat
2100 * @sap: netlabel secattr
2101 * @sip: where to put the result
2103 * Copies a smack label into sip
2105 static void smack_from_secattr(struct netlbl_lsm_secattr *sap, char *sip)
2107 char smack[SMK_LABELLEN];
2110 if ((sap->flags & NETLBL_SECATTR_MLS_LVL) == 0) {
2112 * If there are flags but no level netlabel isn't
2113 * behaving the way we expect it to.
2115 * Without guidance regarding the smack value
2116 * for the packet fall back on the network
2119 strncpy(sip, smack_net_ambient, SMK_MAXLEN);
2123 * Get the categories, if any
2125 memset(smack, '\0', SMK_LABELLEN);
2126 if ((sap->flags & NETLBL_SECATTR_MLS_CAT) != 0)
2128 pcat = netlbl_secattr_catmap_walk(sap->attr.mls.cat,
2132 smack_catset_bit(pcat, smack);
2135 * If it is CIPSO using smack direct mapping
2136 * we are already done. WeeHee.
2138 if (sap->attr.mls.lvl == smack_cipso_direct) {
2139 memcpy(sip, smack, SMK_MAXLEN);
2143 * Look it up in the supplied table if it is not a direct mapping.
2145 smack_from_cipso(sap->attr.mls.lvl, smack, sip);
2150 * smack_socket_sock_rcv_skb - Smack packet delivery access check
2154 * Returns 0 if the packet should be delivered, an error code otherwise
2156 static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
2158 struct netlbl_lsm_secattr secattr;
2159 struct socket_smack *ssp = sk->sk_security;
2160 char smack[SMK_LABELLEN];
2163 if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
2167 * Translate what netlabel gave us.
2169 memset(smack, '\0', SMK_LABELLEN);
2170 netlbl_secattr_init(&secattr);
2171 rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr);
2173 smack_from_secattr(&secattr, smack);
2175 strncpy(smack, smack_net_ambient, SMK_MAXLEN);
2176 netlbl_secattr_destroy(&secattr);
2178 * Receiving a packet requires that the other end
2179 * be able to write here. Read access is not required.
2180 * This is the simplist possible security model
2183 rc = smk_access(smack, ssp->smk_in, MAY_WRITE);
2185 netlbl_skbuff_err(skb, rc, 0);
2190 * smack_socket_getpeersec_stream - pull in packet label
2192 * @optval: user's destination
2193 * @optlen: size thereof
2196 * returns zero on success, an error code otherwise
2198 static int smack_socket_getpeersec_stream(struct socket *sock,
2199 char __user *optval,
2200 int __user *optlen, unsigned len)
2202 struct socket_smack *ssp;
2206 ssp = sock->sk->sk_security;
2207 slen = strlen(ssp->smk_packet) + 1;
2211 else if (copy_to_user(optval, ssp->smk_packet, slen) != 0)
2214 if (put_user(slen, optlen) != 0)
2222 * smack_socket_getpeersec_dgram - pull in packet label
2225 * @secid: pointer to where to put the secid of the packet
2227 * Sets the netlabel socket state on sk from parent
2229 static int smack_socket_getpeersec_dgram(struct socket *sock,
2230 struct sk_buff *skb, u32 *secid)
2233 struct netlbl_lsm_secattr secattr;
2235 char smack[SMK_LABELLEN];
2236 int family = PF_INET;
2241 * Only works for families with packets.
2245 if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
2247 family = sk->sk_family;
2250 * Translate what netlabel gave us.
2252 memset(smack, '\0', SMK_LABELLEN);
2253 netlbl_secattr_init(&secattr);
2254 rc = netlbl_skbuff_getattr(skb, family, &secattr);
2256 smack_from_secattr(&secattr, smack);
2257 netlbl_secattr_destroy(&secattr);
2260 * Give up if we couldn't get anything
2265 s = smack_to_secid(smack);
2274 * smack_sock_graft - graft access state between two sockets
2276 * @parent: donor socket
2278 * Sets the netlabel socket state on sk from parent
2280 static void smack_sock_graft(struct sock *sk, struct socket *parent)
2282 struct socket_smack *ssp;
2288 if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)
2291 ssp = sk->sk_security;
2292 ssp->smk_in = ssp->smk_out = current_security();
2293 ssp->smk_packet[0] = '\0';
2295 rc = smack_netlabel(sk);
2297 printk(KERN_WARNING "Smack: \"%s\" netlbl error %d.\n",
2302 * smack_inet_conn_request - Smack access check on connect
2303 * @sk: socket involved
2307 * Returns 0 if a task with the packet label could write to
2308 * the socket, otherwise an error code
2310 static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb,
2311 struct request_sock *req)
2313 struct netlbl_lsm_secattr skb_secattr;
2314 struct socket_smack *ssp = sk->sk_security;
2315 char smack[SMK_LABELLEN];
2321 memset(smack, '\0', SMK_LABELLEN);
2322 netlbl_secattr_init(&skb_secattr);
2323 rc = netlbl_skbuff_getattr(skb, sk->sk_family, &skb_secattr);
2325 smack_from_secattr(&skb_secattr, smack);
2327 strncpy(smack, smack_known_huh.smk_known, SMK_MAXLEN);
2328 netlbl_secattr_destroy(&skb_secattr);
2330 * Receiving a packet requires that the other end
2331 * be able to write here. Read access is not required.
2333 * If the request is successful save the peer's label
2334 * so that SO_PEERCRED can report it.
2336 rc = smk_access(smack, ssp->smk_in, MAY_WRITE);
2338 strncpy(ssp->smk_packet, smack, SMK_MAXLEN);
2344 * Key management security hooks
2346 * Casey has not tested key support very heavily.
2347 * The permission check is most likely too restrictive.
2348 * If you care about keys please have a look.
2353 * smack_key_alloc - Set the key security blob
2355 * @tsk: the task associated with the key
2358 * No allocation required
2362 static int smack_key_alloc(struct key *key, struct task_struct *tsk,
2363 unsigned long flags)
2365 key->security = tsk->cred->security;
2370 * smack_key_free - Clear the key security blob
2373 * Clear the blob pointer
2375 static void smack_key_free(struct key *key)
2377 key->security = NULL;
2381 * smack_key_permission - Smack access on a key
2382 * @key_ref: gets to the object
2383 * @context: task involved
2386 * Return 0 if the task has read and write to the object,
2387 * an error code otherwise
2389 static int smack_key_permission(key_ref_t key_ref,
2390 struct task_struct *context, key_perm_t perm)
2394 keyp = key_ref_to_ptr(key_ref);
2398 * If the key hasn't been initialized give it access so that
2401 if (keyp->security == NULL)
2404 * This should not occur
2406 if (context->cred->security == NULL)
2409 return smk_access(context->cred->security, keyp->security,
2412 #endif /* CONFIG_KEYS */
2417 * Audit requires a unique representation of each Smack specific
2418 * rule. This unique representation is used to distinguish the
2419 * object to be audited from remaining kernel objects and also
2420 * works as a glue between the audit hooks.
2422 * Since repository entries are added but never deleted, we'll use
2423 * the smack_known label address related to the given audit rule as
2424 * the needed unique representation. This also better fits the smack
2425 * model where nearly everything is a label.
2430 * smack_audit_rule_init - Initialize a smack audit rule
2431 * @field: audit rule fields given from user-space (audit.h)
2432 * @op: required testing operator (=, !=, >, <, ...)
2433 * @rulestr: smack label to be audited
2434 * @vrule: pointer to save our own audit rule representation
2436 * Prepare to audit cases where (@field @op @rulestr) is true.
2437 * The label to be audited is created if necessay.
2439 static int smack_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
2441 char **rule = (char **)vrule;
2444 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
2447 if (op != AUDIT_EQUAL && op != AUDIT_NOT_EQUAL)
2450 *rule = smk_import(rulestr, 0);
2456 * smack_audit_rule_known - Distinguish Smack audit rules
2457 * @krule: rule of interest, in Audit kernel representation format
2459 * This is used to filter Smack rules from remaining Audit ones.
2460 * If it's proved that this rule belongs to us, the
2461 * audit_rule_match hook will be called to do the final judgement.
2463 static int smack_audit_rule_known(struct audit_krule *krule)
2465 struct audit_field *f;
2468 for (i = 0; i < krule->field_count; i++) {
2469 f = &krule->fields[i];
2471 if (f->type == AUDIT_SUBJ_USER || f->type == AUDIT_OBJ_USER)
2479 * smack_audit_rule_match - Audit given object ?
2480 * @secid: security id for identifying the object to test
2481 * @field: audit rule flags given from user-space
2482 * @op: required testing operator
2483 * @vrule: smack internal rule presentation
2484 * @actx: audit context associated with the check
2486 * The core Audit hook. It's used to take the decision of
2487 * whether to audit or not to audit a given object.
2489 static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule,
2490 struct audit_context *actx)
2496 audit_log(actx, GFP_KERNEL, AUDIT_SELINUX_ERR,
2497 "Smack: missing rule\n");
2501 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER)
2504 smack = smack_from_secid(secid);
2507 * No need to do string comparisons. If a match occurs,
2508 * both pointers will point to the same smack_known
2511 if (op == AUDIT_EQUAL)
2512 return (rule == smack);
2513 if (op == AUDIT_NOT_EQUAL)
2514 return (rule != smack);
2520 * smack_audit_rule_free - free smack rule representation
2521 * @vrule: rule to be freed.
2523 * No memory was allocated.
2525 static void smack_audit_rule_free(void *vrule)
2530 #endif /* CONFIG_AUDIT */
2533 * smack_secid_to_secctx - return the smack label for a secid
2534 * @secid: incoming integer
2535 * @secdata: destination
2536 * @seclen: how long it is
2538 * Exists for networking code.
2540 static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
2542 char *sp = smack_from_secid(secid);
2545 *seclen = strlen(sp);
2550 * smack_secctx_to_secid - return the secid for a smack label
2551 * @secdata: smack label
2552 * @seclen: how long result is
2553 * @secid: outgoing integer
2555 * Exists for audit and networking code.
2557 static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
2559 *secid = smack_to_secid(secdata);
2564 * smack_release_secctx - don't do anything.
2569 * Exists to make sure nothing gets done, and properly
2571 static void smack_release_secctx(char *secdata, u32 seclen)
2575 struct security_operations smack_ops = {
2578 .ptrace_may_access = smack_ptrace_may_access,
2579 .ptrace_traceme = smack_ptrace_traceme,
2580 .capget = cap_capget,
2581 .capset_check = cap_capset_check,
2582 .capset_set = cap_capset_set,
2583 .capable = cap_capable,
2584 .syslog = smack_syslog,
2585 .settime = cap_settime,
2586 .vm_enough_memory = cap_vm_enough_memory,
2588 .bprm_apply_creds = cap_bprm_apply_creds,
2589 .bprm_set_security = cap_bprm_set_security,
2590 .bprm_secureexec = cap_bprm_secureexec,
2592 .sb_alloc_security = smack_sb_alloc_security,
2593 .sb_free_security = smack_sb_free_security,
2594 .sb_copy_data = smack_sb_copy_data,
2595 .sb_kern_mount = smack_sb_kern_mount,
2596 .sb_statfs = smack_sb_statfs,
2597 .sb_mount = smack_sb_mount,
2598 .sb_umount = smack_sb_umount,
2600 .inode_alloc_security = smack_inode_alloc_security,
2601 .inode_free_security = smack_inode_free_security,
2602 .inode_init_security = smack_inode_init_security,
2603 .inode_link = smack_inode_link,
2604 .inode_unlink = smack_inode_unlink,
2605 .inode_rmdir = smack_inode_rmdir,
2606 .inode_rename = smack_inode_rename,
2607 .inode_permission = smack_inode_permission,
2608 .inode_setattr = smack_inode_setattr,
2609 .inode_getattr = smack_inode_getattr,
2610 .inode_setxattr = smack_inode_setxattr,
2611 .inode_post_setxattr = smack_inode_post_setxattr,
2612 .inode_getxattr = smack_inode_getxattr,
2613 .inode_removexattr = smack_inode_removexattr,
2614 .inode_need_killpriv = cap_inode_need_killpriv,
2615 .inode_killpriv = cap_inode_killpriv,
2616 .inode_getsecurity = smack_inode_getsecurity,
2617 .inode_setsecurity = smack_inode_setsecurity,
2618 .inode_listsecurity = smack_inode_listsecurity,
2619 .inode_getsecid = smack_inode_getsecid,
2621 .file_permission = smack_file_permission,
2622 .file_alloc_security = smack_file_alloc_security,
2623 .file_free_security = smack_file_free_security,
2624 .file_ioctl = smack_file_ioctl,
2625 .file_lock = smack_file_lock,
2626 .file_fcntl = smack_file_fcntl,
2627 .file_set_fowner = smack_file_set_fowner,
2628 .file_send_sigiotask = smack_file_send_sigiotask,
2629 .file_receive = smack_file_receive,
2631 .cred_alloc_security = smack_cred_alloc_security,
2632 .cred_free = smack_cred_free,
2633 .task_post_setuid = cap_task_post_setuid,
2634 .task_setpgid = smack_task_setpgid,
2635 .task_getpgid = smack_task_getpgid,
2636 .task_getsid = smack_task_getsid,
2637 .task_getsecid = smack_task_getsecid,
2638 .task_setnice = smack_task_setnice,
2639 .task_setioprio = smack_task_setioprio,
2640 .task_getioprio = smack_task_getioprio,
2641 .task_setscheduler = smack_task_setscheduler,
2642 .task_getscheduler = smack_task_getscheduler,
2643 .task_movememory = smack_task_movememory,
2644 .task_kill = smack_task_kill,
2645 .task_wait = smack_task_wait,
2646 .task_reparent_to_init = cap_task_reparent_to_init,
2647 .task_to_inode = smack_task_to_inode,
2648 .task_prctl = cap_task_prctl,
2650 .ipc_permission = smack_ipc_permission,
2651 .ipc_getsecid = smack_ipc_getsecid,
2653 .msg_msg_alloc_security = smack_msg_msg_alloc_security,
2654 .msg_msg_free_security = smack_msg_msg_free_security,
2656 .msg_queue_alloc_security = smack_msg_queue_alloc_security,
2657 .msg_queue_free_security = smack_msg_queue_free_security,
2658 .msg_queue_associate = smack_msg_queue_associate,
2659 .msg_queue_msgctl = smack_msg_queue_msgctl,
2660 .msg_queue_msgsnd = smack_msg_queue_msgsnd,
2661 .msg_queue_msgrcv = smack_msg_queue_msgrcv,
2663 .shm_alloc_security = smack_shm_alloc_security,
2664 .shm_free_security = smack_shm_free_security,
2665 .shm_associate = smack_shm_associate,
2666 .shm_shmctl = smack_shm_shmctl,
2667 .shm_shmat = smack_shm_shmat,
2669 .sem_alloc_security = smack_sem_alloc_security,
2670 .sem_free_security = smack_sem_free_security,
2671 .sem_associate = smack_sem_associate,
2672 .sem_semctl = smack_sem_semctl,
2673 .sem_semop = smack_sem_semop,
2675 .netlink_send = cap_netlink_send,
2676 .netlink_recv = cap_netlink_recv,
2678 .d_instantiate = smack_d_instantiate,
2680 .getprocattr = smack_getprocattr,
2681 .setprocattr = smack_setprocattr,
2683 .unix_stream_connect = smack_unix_stream_connect,
2684 .unix_may_send = smack_unix_may_send,
2686 .socket_post_create = smack_socket_post_create,
2687 .socket_sock_rcv_skb = smack_socket_sock_rcv_skb,
2688 .socket_getpeersec_stream = smack_socket_getpeersec_stream,
2689 .socket_getpeersec_dgram = smack_socket_getpeersec_dgram,
2690 .sk_alloc_security = smack_sk_alloc_security,
2691 .sk_free_security = smack_sk_free_security,
2692 .sock_graft = smack_sock_graft,
2693 .inet_conn_request = smack_inet_conn_request,
2695 /* key management security hooks */
2697 .key_alloc = smack_key_alloc,
2698 .key_free = smack_key_free,
2699 .key_permission = smack_key_permission,
2700 #endif /* CONFIG_KEYS */
2704 .audit_rule_init = smack_audit_rule_init,
2705 .audit_rule_known = smack_audit_rule_known,
2706 .audit_rule_match = smack_audit_rule_match,
2707 .audit_rule_free = smack_audit_rule_free,
2708 #endif /* CONFIG_AUDIT */
2710 .secid_to_secctx = smack_secid_to_secctx,
2711 .secctx_to_secid = smack_secctx_to_secid,
2712 .release_secctx = smack_release_secctx,
2716 * smack_init - initialize the smack system
2720 static __init int smack_init(void)
2722 if (!security_module_enable(&smack_ops))
2725 printk(KERN_INFO "Smack: Initializing.\n");
2728 * Set the security state for the initial task.
2730 current->cred->security = &smack_known_floor.smk_known;
2735 spin_lock_init(&smack_known_unset.smk_cipsolock);
2736 spin_lock_init(&smack_known_huh.smk_cipsolock);
2737 spin_lock_init(&smack_known_hat.smk_cipsolock);
2738 spin_lock_init(&smack_known_star.smk_cipsolock);
2739 spin_lock_init(&smack_known_floor.smk_cipsolock);
2740 spin_lock_init(&smack_known_invalid.smk_cipsolock);
2745 if (register_security(&smack_ops))
2746 panic("smack: Unable to register with kernel.\n");
2752 * Smack requires early initialization in order to label
2753 * all processes and objects when they are created.
2755 security_initcall(smack_init);