[deliverable/linux.git] / security / tomoyo / tomoyo.c

/*
 * security/tomoyo/tomoyo.c
 *
 * LSM hooks for TOMOYO Linux.
 *
 * Copyright (C) 2005-2009  NTT DATA CORPORATION
 *
 * Version: 2.2.0   2009/04/01
 *
 */

#include <linux/security.h>
#include "common.h"
#include "tomoyo.h"
#include "realpath.h"

static int tomoyo_cred_alloc_blank(struct cred *new, gfp_t gfp)
{
	new->security = NULL;
	return 0;
}

static int tomoyo_cred_prepare(struct cred *new, const struct cred *old,
			       gfp_t gfp)
{
	/*
	 * Since "struct tomoyo_domain_info *" is a sharable pointer,
	 * we don't need to duplicate.
	 */
	new->security = old->security;
	return 0;
}

static void tomoyo_cred_transfer(struct cred *new, const struct cred *old)
{
	/*
	 * Since "struct tomoyo_domain_info *" is a sharable pointer,
	 * we don't need to duplicate.
	 */
	new->security = old->security;
}

static int tomoyo_bprm_set_creds(struct linux_binprm *bprm)
{
	int rc;

	rc = cap_bprm_set_creds(bprm);
	if (rc)
		return rc;

	/*
	 * Do only if this function is called for the first time of an execve
	 * operation.
	 */
	if (bprm->cred_prepared)
		return 0;
	/*
	 * Load policy if /sbin/tomoyo-init exists and /sbin/init is requested
	 * for the first time.
	 */
	if (!tomoyo_policy_loaded)
		tomoyo_load_policy(bprm->filename);
	/*
	 * Tell tomoyo_bprm_check_security() is called for the first time of an
	 * execve operation.
	 */
	bprm->cred->security = NULL;
	return 0;
}

static int tomoyo_bprm_check_security(struct linux_binprm *bprm)
{
	struct tomoyo_domain_info *domain = bprm->cred->security;

	/*
	 * Execute permission is checked against pathname passed to do_execve()
	 * using current domain.
	 */
	if (!domain)
		return tomoyo_find_next_domain(bprm);
	/*
	 * Read permission is checked against interpreters using next domain.
	 * '1' is the result of open_to_namei_flags(O_RDONLY).
	 */
	return tomoyo_check_open_permission(domain, &bprm->file->f_path, 1);
}

static int tomoyo_path_truncate(struct path *path, loff_t length,
				unsigned int time_attrs)
{
	return tomoyo_check_1path_perm(tomoyo_domain(),
				       TOMOYO_TYPE_TRUNCATE_ACL,
				       path);
}

static int tomoyo_path_unlink(struct path *parent, struct dentry *dentry)
{
	struct path path = { parent->mnt, dentry };
	return tomoyo_check_1path_perm(tomoyo_domain(),
				       TOMOYO_TYPE_UNLINK_ACL,
				       &path);
}

static int tomoyo_path_mkdir(struct path *parent, struct dentry *dentry,
			     int mode)
{
	struct path path = { parent->mnt, dentry };
	return tomoyo_check_1path_perm(tomoyo_domain(),
				       TOMOYO_TYPE_MKDIR_ACL,
				       &path);
}

static int tomoyo_path_rmdir(struct path *parent, struct dentry *dentry)
{
	struct path path = { parent->mnt, dentry };
	return tomoyo_check_1path_perm(tomoyo_domain(),
				       TOMOYO_TYPE_RMDIR_ACL,
				       &path);
}

static int tomoyo_path_symlink(struct path *parent, struct dentry *dentry,
			       const char *old_name)
{
	struct path path = { parent->mnt, dentry };
	return tomoyo_check_1path_perm(tomoyo_domain(),
				       TOMOYO_TYPE_SYMLINK_ACL,
				       &path);
}

static int tomoyo_path_mknod(struct path *parent, struct dentry *dentry,
			     int mode, unsigned int dev)
{
	struct path path = { parent->mnt, dentry };
	int type = TOMOYO_TYPE_CREATE_ACL;

	switch (mode & S_IFMT) {
	case S_IFCHR:
		type = TOMOYO_TYPE_MKCHAR_ACL;
		break;
	case S_IFBLK:
		type = TOMOYO_TYPE_MKBLOCK_ACL;
		break;
	case S_IFIFO:
		type = TOMOYO_TYPE_MKFIFO_ACL;
		break;
	case S_IFSOCK:
		type = TOMOYO_TYPE_MKSOCK_ACL;
		break;
	}
	return tomoyo_check_1path_perm(tomoyo_domain(),
				       type, &path);
}

static int tomoyo_path_link(struct dentry *old_dentry, struct path *new_dir,
			    struct dentry *new_dentry)
{
	struct path path1 = { new_dir->mnt, old_dentry };
	struct path path2 = { new_dir->mnt, new_dentry };
	return tomoyo_check_2path_perm(tomoyo_domain(),
				       TOMOYO_TYPE_LINK_ACL,
				       &path1, &path2);
}

static int tomoyo_path_rename(struct path *old_parent,
			      struct dentry *old_dentry,
			      struct path *new_parent,
			      struct dentry *new_dentry)
{
	struct path path1 = { old_parent->mnt, old_dentry };
	struct path path2 = { new_parent->mnt, new_dentry };
	return tomoyo_check_2path_perm(tomoyo_domain(),
				       TOMOYO_TYPE_RENAME_ACL,
				       &path1, &path2);
}

static int tomoyo_file_fcntl(struct file *file, unsigned int cmd,
			     unsigned long arg)
{
	if (cmd == F_SETFL && ((arg ^ file->f_flags) & O_APPEND))
		return tomoyo_check_rewrite_permission(tomoyo_domain(), file);
	return 0;
}

static int tomoyo_dentry_open(struct file *f, const struct cred *cred)
{
	int flags = f->f_flags;

	if ((flags + 1) & O_ACCMODE)
		flags++;
	flags |= f->f_flags & (O_APPEND | O_TRUNC);
	/* Don't check read permission here if called from do_execve(). */
	if (current->in_execve)
		return 0;
	return tomoyo_check_open_permission(tomoyo_domain(), &f->f_path, flags);
}

static int tomoyo_file_ioctl(struct file *file, unsigned int cmd,
			     unsigned long arg)
{
	return tomoyo_check_1path_perm(tomoyo_domain(), TOMOYO_TYPE_IOCTL_ACL,
				       &file->f_path);
}

static int tomoyo_path_chmod(struct dentry *dentry, struct vfsmount *mnt,
			     mode_t mode)
{
	struct path path = { mnt, dentry };
	return tomoyo_check_1path_perm(tomoyo_domain(), TOMOYO_TYPE_CHMOD_ACL,
				       &path);
}

static int tomoyo_path_chown(struct path *path, uid_t uid, gid_t gid)
{
	int error = 0;
	if (uid != (uid_t) -1)
		error = tomoyo_check_1path_perm(tomoyo_domain(),
						TOMOYO_TYPE_CHOWN_ACL, path);
	if (!error && gid != (gid_t) -1)
		error = tomoyo_check_1path_perm(tomoyo_domain(),
						TOMOYO_TYPE_CHGRP_ACL, path);
	return error;
}

static int tomoyo_path_chroot(struct path *path)
{
	return tomoyo_check_1path_perm(tomoyo_domain(), TOMOYO_TYPE_CHROOT_ACL,
				       path);
}

static int tomoyo_sb_mount(char *dev_name, struct path *path,
			   char *type, unsigned long flags, void *data)
{
	return tomoyo_check_1path_perm(tomoyo_domain(), TOMOYO_TYPE_MOUNT_ACL,
				       path);
}

static int tomoyo_sb_umount(struct vfsmount *mnt, int flags)
{
	struct path path = { mnt, mnt->mnt_root };
	return tomoyo_check_1path_perm(tomoyo_domain(), TOMOYO_TYPE_UMOUNT_ACL,
				       &path);
}

static int tomoyo_sb_pivotroot(struct path *old_path, struct path *new_path)
{
	return tomoyo_check_2path_perm(tomoyo_domain(),
				       TOMOYO_TYPE_PIVOT_ROOT_ACL,
				       new_path, old_path);
}

/*
 * tomoyo_security_ops is a "struct security_operations" which is used for
 * registering TOMOYO.
 */
static struct security_operations tomoyo_security_ops = {
	.name                = "tomoyo",
	.cred_alloc_blank    = tomoyo_cred_alloc_blank,
	.cred_prepare        = tomoyo_cred_prepare,
	.cred_transfer	     = tomoyo_cred_transfer,
	.bprm_set_creds      = tomoyo_bprm_set_creds,
	.bprm_check_security = tomoyo_bprm_check_security,
	.file_fcntl          = tomoyo_file_fcntl,
	.dentry_open         = tomoyo_dentry_open,
	.path_truncate       = tomoyo_path_truncate,
	.path_unlink         = tomoyo_path_unlink,
	.path_mkdir          = tomoyo_path_mkdir,
	.path_rmdir          = tomoyo_path_rmdir,
	.path_symlink        = tomoyo_path_symlink,
	.path_mknod          = tomoyo_path_mknod,
	.path_link           = tomoyo_path_link,
	.path_rename         = tomoyo_path_rename,
	.file_ioctl          = tomoyo_file_ioctl,
	.path_chmod          = tomoyo_path_chmod,
	.path_chown          = tomoyo_path_chown,
	.path_chroot         = tomoyo_path_chroot,
	.sb_mount            = tomoyo_sb_mount,
	.sb_umount           = tomoyo_sb_umount,
	.sb_pivotroot        = tomoyo_sb_pivotroot,
};

static int __init tomoyo_init(void)
{
	struct cred *cred = (struct cred *) current_cred();

	if (!security_module_enable(&tomoyo_security_ops))
		return 0;
	/* register ourselves with the security framework */
	if (register_security(&tomoyo_security_ops))
		panic("Failure registering TOMOYO Linux");
	printk(KERN_INFO "TOMOYO Linux initialized\n");
	cred->security = &tomoyo_kernel_domain;
	tomoyo_realpath_init();
	return 0;
}

security_initcall(tomoyo_init);
Commit	Line	Data
f7433243 KT	1	/*
	2	* security/tomoyo/tomoyo.c
	3	*
	4	* LSM hooks for TOMOYO Linux.
	5	*
	6	* Copyright (C) 2005-2009 NTT DATA CORPORATION
	7	*
39826a1e	8	* Version: 2.2.0 2009/04/01
f7433243 KT	9	*
	10	*/
	11
	12	#include <linux/security.h>
	13	#include "common.h"
	14	#include "tomoyo.h"
	15	#include "realpath.h"
	16
ee18d64c DH	17	static int tomoyo_cred_alloc_blank(struct cred *new, gfp_t gfp)
	18	{
	19	new->security = NULL;
	20	return 0;
	21	}
	22
f7433243 KT	23	static int tomoyo_cred_prepare(struct cred new, const struct cred old,
	24	gfp_t gfp)
	25	{
	26	/*
	27	* Since "struct tomoyo_domain_info *" is a sharable pointer,
	28	* we don't need to duplicate.
	29	*/
	30	new->security = old->security;
	31	return 0;
	32	}
	33
ee18d64c DH	34	static void tomoyo_cred_transfer(struct cred new, const struct cred old)
	35	{
	36	/*
	37	* Since "struct tomoyo_domain_info *" is a sharable pointer,
	38	* we don't need to duplicate.
	39	*/
	40	new->security = old->security;
	41	}
	42
f7433243 KT	43	static int tomoyo_bprm_set_creds(struct linux_binprm *bprm)
f7433243 KT	44	{
b1338d19 HRK	45	int rc;
	46
	47	rc = cap_bprm_set_creds(bprm);
	48	if (rc)
	49	return rc;
	50
f7433243 KT	51	/*
	52	* Do only if this function is called for the first time of an execve
	53	* operation.
	54	*/
	55	if (bprm->cred_prepared)
	56	return 0;
	57	/*
	58	* Load policy if /sbin/tomoyo-init exists and /sbin/init is requested
	59	* for the first time.
	60	*/
	61	if (!tomoyo_policy_loaded)
	62	tomoyo_load_policy(bprm->filename);
	63	/*
	64	* Tell tomoyo_bprm_check_security() is called for the first time of an
	65	* execve operation.
	66	*/
	67	bprm->cred->security = NULL;
	68	return 0;
	69	}
	70
	71	static int tomoyo_bprm_check_security(struct linux_binprm *bprm)
	72	{
	73	struct tomoyo_domain_info *domain = bprm->cred->security;
	74
	75	/*
	76	* Execute permission is checked against pathname passed to do_execve()
	77	* using current domain.
	78	*/
56f8c9bc TH	79	if (!domain)
56f8c9bc TH	80	return tomoyo_find_next_domain(bprm);
f7433243 KT	81	/*
	82	* Read permission is checked against interpreters using next domain.
	83	* '1' is the result of open_to_namei_flags(O_RDONLY).
	84	*/
	85	return tomoyo_check_open_permission(domain, &bprm->file->f_path, 1);
	86	}
	87
f7433243 KT	88	static int tomoyo_path_truncate(struct path *path, loff_t length,
	89	unsigned int time_attrs)
	90	{
	91	return tomoyo_check_1path_perm(tomoyo_domain(),
	92	TOMOYO_TYPE_TRUNCATE_ACL,
	93	path);
	94	}
	95
	96	static int tomoyo_path_unlink(struct path parent, struct dentry dentry)
	97	{
	98	struct path path = { parent->mnt, dentry };
	99	return tomoyo_check_1path_perm(tomoyo_domain(),
	100	TOMOYO_TYPE_UNLINK_ACL,
	101	&path);
	102	}
	103
	104	static int tomoyo_path_mkdir(struct path parent, struct dentry dentry,
	105	int mode)
	106	{
	107	struct path path = { parent->mnt, dentry };
	108	return tomoyo_check_1path_perm(tomoyo_domain(),
	109	TOMOYO_TYPE_MKDIR_ACL,
	110	&path);
	111	}
	112
	113	static int tomoyo_path_rmdir(struct path parent, struct dentry dentry)
	114	{
	115	struct path path = { parent->mnt, dentry };
	116	return tomoyo_check_1path_perm(tomoyo_domain(),
	117	TOMOYO_TYPE_RMDIR_ACL,
	118	&path);
	119	}
	120
	121	static int tomoyo_path_symlink(struct path parent, struct dentry dentry,
	122	const char *old_name)
	123	{
	124	struct path path = { parent->mnt, dentry };
	125	return tomoyo_check_1path_perm(tomoyo_domain(),
	126	TOMOYO_TYPE_SYMLINK_ACL,
	127	&path);
	128	}
	129
	130	static int tomoyo_path_mknod(struct path parent, struct dentry dentry,
	131	int mode, unsigned int dev)
	132	{
	133	struct path path = { parent->mnt, dentry };
	134	int type = TOMOYO_TYPE_CREATE_ACL;
	135
	136	switch (mode & S_IFMT) {
	137	case S_IFCHR:
	138	type = TOMOYO_TYPE_MKCHAR_ACL;
	139	break;
	140	case S_IFBLK:
	141	type = TOMOYO_TYPE_MKBLOCK_ACL;
	142	break;
	143	case S_IFIFO:
	144	type = TOMOYO_TYPE_MKFIFO_ACL;
	145	break;
	146	case S_IFSOCK:
	147	type = TOMOYO_TYPE_MKSOCK_ACL;
	148	break;
	149	}
	150	return tomoyo_check_1path_perm(tomoyo_domain(),
	151	type, &path);
152	}
153
154	static int tomoyo_path_link(struct dentry old_dentry, struct path new_dir,
155	struct dentry *new_dentry)
156	{
157	struct path path1 = { new_dir->mnt, old_dentry };
158	struct path path2 = { new_dir->mnt, new_dentry };
159	return tomoyo_check_2path_perm(tomoyo_domain(),
160	TOMOYO_TYPE_LINK_ACL,
161	&path1, &path2);
162	}
163
164	static int tomoyo_path_rename(struct path *old_parent,
165	struct dentry *old_dentry,
166	struct path *new_parent,
167	struct dentry *new_dentry)
168	{
169	struct path path1 = { old_parent->mnt, old_dentry };
170	struct path path2 = { new_parent->mnt, new_dentry };
171	return tomoyo_check_2path_perm(tomoyo_domain(),
172	TOMOYO_TYPE_RENAME_ACL,
173	&path1, &path2);
174	}
175
176	static int tomoyo_file_fcntl(struct file *file, unsigned int cmd,
177	unsigned long arg)
178	{
179	if (cmd == F_SETFL && ((arg ^ file->f_flags) & O_APPEND))
180	return tomoyo_check_rewrite_permission(tomoyo_domain(), file);
181	return 0;
182	}
183
184	static int tomoyo_dentry_open(struct file f, const struct cred cred)
185	{
186	int flags = f->f_flags;
187
188	if ((flags + 1) & O_ACCMODE)
189	flags++;
190	flags \|= f->f_flags & (O_APPEND \| O_TRUNC);
191	/* Don't check read permission here if called from do_execve(). */
192	if (current->in_execve)
193	return 0;
194	return tomoyo_check_open_permission(tomoyo_domain(), &f->f_path, flags);
195	}
196
937bf613 TH	197	static int tomoyo_file_ioctl(struct file *file, unsigned int cmd,
	198	unsigned long arg)
	199	{
	200	return tomoyo_check_1path_perm(tomoyo_domain(), TOMOYO_TYPE_IOCTL_ACL,
	201	&file->f_path);
	202	}
	203
	204	static int tomoyo_path_chmod(struct dentry dentry, struct vfsmount mnt,
	205	mode_t mode)
	206	{
	207	struct path path = { mnt, dentry };
	208	return tomoyo_check_1path_perm(tomoyo_domain(), TOMOYO_TYPE_CHMOD_ACL,
	209	&path);
	210	}
	211
	212	static int tomoyo_path_chown(struct path *path, uid_t uid, gid_t gid)
	213	{
	214	int error = 0;
	215	if (uid != (uid_t) -1)
	216	error = tomoyo_check_1path_perm(tomoyo_domain(),
	217	TOMOYO_TYPE_CHOWN_ACL, path);
	218	if (!error && gid != (gid_t) -1)
	219	error = tomoyo_check_1path_perm(tomoyo_domain(),
	220	TOMOYO_TYPE_CHGRP_ACL, path);
	221	return error;
	222	}
	223
	224	static int tomoyo_path_chroot(struct path *path)
	225	{
	226	return tomoyo_check_1path_perm(tomoyo_domain(), TOMOYO_TYPE_CHROOT_ACL,
	227	path);
	228	}
	229
	230	static int tomoyo_sb_mount(char dev_name, struct path path,
	231	char type, unsigned long flags, void data)
	232	{
	233	return tomoyo_check_1path_perm(tomoyo_domain(), TOMOYO_TYPE_MOUNT_ACL,
	234	path);
	235	}
	236
	237	static int tomoyo_sb_umount(struct vfsmount *mnt, int flags)
	238	{
	239	struct path path = { mnt, mnt->mnt_root };
	240	return tomoyo_check_1path_perm(tomoyo_domain(), TOMOYO_TYPE_UMOUNT_ACL,
	241	&path);
	242	}
	243
	244	static int tomoyo_sb_pivotroot(struct path old_path, struct path new_path)
	245	{
	246	return tomoyo_check_2path_perm(tomoyo_domain(),
	247	TOMOYO_TYPE_PIVOT_ROOT_ACL,
	248	new_path, old_path);
	249	}
	250
c3fa109a TH	251	/*
	252	* tomoyo_security_ops is a "struct security_operations" which is used for
	253	* registering TOMOYO.
	254	*/
f7433243 KT	255	static struct security_operations tomoyo_security_ops = {
f7433243 KT	256	.name = "tomoyo",
ee18d64c	257	.cred_alloc_blank = tomoyo_cred_alloc_blank,
f7433243	258	.cred_prepare = tomoyo_cred_prepare,
ee18d64c	259	.cred_transfer = tomoyo_cred_transfer,
f7433243 KT	260	.bprm_set_creds = tomoyo_bprm_set_creds,
f7433243 KT	261	.bprm_check_security = tomoyo_bprm_check_security,
f7433243 KT	262	.file_fcntl = tomoyo_file_fcntl,
	263	.dentry_open = tomoyo_dentry_open,
	264	.path_truncate = tomoyo_path_truncate,
	265	.path_unlink = tomoyo_path_unlink,
	266	.path_mkdir = tomoyo_path_mkdir,
	267	.path_rmdir = tomoyo_path_rmdir,
	268	.path_symlink = tomoyo_path_symlink,
	269	.path_mknod = tomoyo_path_mknod,
	270	.path_link = tomoyo_path_link,
	271	.path_rename = tomoyo_path_rename,
937bf613 TH	272	.file_ioctl = tomoyo_file_ioctl,
	273	.path_chmod = tomoyo_path_chmod,
	274	.path_chown = tomoyo_path_chown,
	275	.path_chroot = tomoyo_path_chroot,
	276	.sb_mount = tomoyo_sb_mount,
	277	.sb_umount = tomoyo_sb_umount,
	278	.sb_pivotroot = tomoyo_sb_pivotroot,
f7433243 KT	279	};
	280
	281	static int __init tomoyo_init(void)
	282	{
	283	struct cred cred = (struct cred ) current_cred();
	284
	285	if (!security_module_enable(&tomoyo_security_ops))
	286	return 0;
	287	/* register ourselves with the security framework */
	288	if (register_security(&tomoyo_security_ops))
	289	panic("Failure registering TOMOYO Linux");
	290	printk(KERN_INFO "TOMOYO Linux initialized\n");
	291	cred->security = &tomoyo_kernel_domain;
1581e7dd	292	tomoyo_realpath_init();
f7433243 KT	293	return 0;
	294	}
	295
	296	security_initcall(tomoyo_init);