TOMOYO Linux

@@ -1571,12 +1571,17 @@ int may_open(struct nameidata *nd, int a
 		 * Refuse to truncate files with mandatory locks held on them.
 		 */
 		error = locks_verify_locked(inode);
+		if (!error)
+			error = security_path_truncate(&nd->path, 0,
+					       ATTR_MTIME|ATTR_CTIME|ATTR_OPEN,
+						       NULL);
 		if (!error) {
 			DQUOT_INIT(inode);
 
 			error = do_truncate(dentry, 0,
 					    ATTR_MTIME|ATTR_CTIME|ATTR_OPEN,
 					    NULL);
+			security_path_clear();
 		}
 		put_write_access(inode);
 		if (error)

@@ -1601,7 +1606,12 @@ static int __open_namei_create(struct na
 
 	if (!IS_POSIXACL(dir->d_inode))
 		mode &= ~current->fs->umask;
+	error = security_path_mknod(&nd->path, path->dentry, mode, 0);
+	if (error)
+		goto out_unlock;
 	error = vfs_create(dir->d_inode, path->dentry, mode, nd);
+	security_path_clear();
+out_unlock:
 	mutex_unlock(&dir->d_inode->i_mutex);
 	dput(nd->path.dentry);
 	nd->path.dentry = path->dentry;

@@ -2014,6 +2024,9 @@ asmlinkage long sys_mknodat(int dfd, con
 	error = mnt_want_write(nd.path.mnt);
 	if (error)
 		goto out_dput;
+	error = security_path_mknod(&nd.path, dentry, mode, dev);
+	if (error)
+		goto out_drop_write;
 	switch (mode & S_IFMT) {
 		case 0: case S_IFREG:
 			error = vfs_create(nd.path.dentry->d_inode,dentry,mode,&nd);

@@ -2026,6 +2039,8 @@ asmlinkage long sys_mknodat(int dfd, con
 			error = vfs_mknod(nd.path.dentry->d_inode,dentry,mode,0);
 			break;
 	}
+	security_path_clear();
+out_drop_write:
 	mnt_drop_write(nd.path.mnt);
 out_dput:
 	dput(dentry);

@@ -2085,7 +2100,12 @@ asmlinkage long sys_mkdirat(int dfd, con
 	error = mnt_want_write(nd.path.mnt);
 	if (error)
 		goto out_dput;
+	error = security_path_mkdir(&nd.path, dentry, mode);
+	if (error)
+		goto out_drop_write;
 	error = vfs_mkdir(nd.path.dentry->d_inode, dentry, mode);
+	security_path_clear();
+out_drop_write:
 	mnt_drop_write(nd.path.mnt);
 out_dput:
 	dput(dentry);

@@ -2192,7 +2212,12 @@ static long do_rmdir(int dfd, const char
 	error = mnt_want_write(nd.path.mnt);
 	if (error)
 		goto exit3;
+	error = security_path_rmdir(&nd.path, dentry);
+	if (error)
+		goto exit4;
 	error = vfs_rmdir(nd.path.dentry->d_inode, dentry);
+	security_path_clear();
+exit4:
 	mnt_drop_write(nd.path.mnt);
 exit3:
 	dput(dentry);

@@ -2274,7 +2299,12 @@ static long do_unlinkat(int dfd, const c
 		error = mnt_want_write(nd.path.mnt);
 		if (error)
 			goto exit2;
+		error = security_path_unlink(&nd.path, dentry);
+		if (error)
+			goto exit3;
 		error = vfs_unlink(nd.path.dentry->d_inode, dentry);
+		security_path_clear();
+exit3:
 		mnt_drop_write(nd.path.mnt);
 	exit2:
 		dput(dentry);

@@ -2355,7 +2385,12 @@ asmlinkage long sys_symlinkat(const char
 	error = mnt_want_write(nd.path.mnt);
 	if (error)
 		goto out_dput;
+	error = security_path_symlink(&nd.path, dentry, from);
+	if (error)
+		goto out_drop_write;
 	error = vfs_symlink(nd.path.dentry->d_inode, dentry, from);
+	security_path_clear();
+out_drop_write:
 	mnt_drop_write(nd.path.mnt);
 out_dput:
 	dput(dentry);

@@ -2452,7 +2487,12 @@ asmlinkage long sys_linkat(int olddfd, c
 	error = mnt_want_write(nd.path.mnt);
 	if (error)
 		goto out_dput;
+	error = security_path_link(old_path.dentry, &nd.path, new_dentry);
+	if (error)
+		goto out_drop_write;
 	error = vfs_link(old_path.dentry, nd.path.dentry->d_inode, new_dentry);
+	security_path_clear();
+out_drop_write:
 	mnt_drop_write(nd.path.mnt);
 out_dput:
 	dput(new_dentry);

@@ -2684,8 +2724,14 @@ asmlinkage long sys_renameat(int olddfd,
 	error = mnt_want_write(oldnd.path.mnt);
 	if (error)
 		goto exit5;
+	error = security_path_rename(&oldnd.path, old_dentry,
+				     &newnd.path, new_dentry);
+	if (error)
+		goto exit6;
 	error = vfs_rename(old_dir->d_inode, old_dentry,
 				   new_dir->d_inode, new_dentry);
+	security_path_clear();
+exit6:
 	mnt_drop_write(oldnd.path.mnt);
 exit5:
 	dput(new_dentry);

@@ -272,6 +272,8 @@ static long do_sys_truncate(const char _
 		goto put_write_and_out;
 
 	error = locks_verify_truncate(inode, NULL, length);
+	if (!error)
+		error = security_path_truncate(&path, length, 0, NULL);
 	if (!error) {
 		DQUOT_INIT(inode);
 		error = do_truncate(path.dentry, length, 0, NULL);

@@ -329,6 +331,9 @@ static long do_sys_ftruncate(unsigned in
 
 	error = locks_verify_truncate(inode, file, length);
 	if (!error)
+		error = security_path_truncate(&file->f_path, length,
+					       ATTR_MTIME|ATTR_CTIME, file);
+	if (!error)
 		error = do_truncate(dentry, length, ATTR_MTIME|ATTR_CTIME, file);
 out_putf:
 	fput(file);

215 lines not on this page · raw message

@@ -828,7 +828,12 @@ static int unix_bind(struct socket *sock
 		err = mnt_want_write(nd.path.mnt);
 		if (err)
 			goto out_mknod_dput;
+		err = security_path_mknod(&nd.path, dentry, mode, 0);
+		if (err)
+			goto out_mknod_drop_write;
 		err = vfs_mknod(nd.path.dentry->d_inode, dentry, mode, 0);
+		security_path_clear();
+out_mknod_drop_write:
 		mnt_drop_write(nd.path.mnt);
 		if (err)
 			goto out_mknod_dput;

75 lines not on this page · raw message

79 lines not on this page · raw message

@@ -828,7 +828,12 @@ static int unix_bind(struct socket *sock
 		err = mnt_want_write(nd.path.mnt);
 		if (err)
 			goto out_mknod_dput;
+		err = security_path_mknod(&nd.path, dentry, mode, 0);
+		if (err)
+			goto out_mknod_drop_write;
 		err = vfs_mknod(nd.path.dentry->d_inode, dentry, mode, 0);
+		security_path_clear();
+out_mknod_drop_write:
 		mnt_drop_write(nd.path.mnt);
 		if (err)
 			goto out_mknod_dput;

@@ -1396,6 +1396,7 @@ int compat_do_execve(char * filename,
 	retval = mutex_lock_interruptible(&current->cred_exec_mutex);
 	if (retval < 0)
 		goto out_free;
+	current->in_execve = 1;
 
 	retval = -ENOMEM;
 	bprm->cred = prepare_exec_creds();

@@ -1448,6 +1449,7 @@ int compat_do_execve(char * filename,
 		goto out;
 
 	/* execve succeeded */
+	current->in_execve = 0;
 	mutex_unlock(&current->cred_exec_mutex);
 	acct_update_integrals(current);
 	free_bprm(bprm);

@@ -1464,6 +1466,7 @@ out_file:
 	}
 
 out_unlock:
+	current->in_execve = 0;
 	mutex_unlock(&current->cred_exec_mutex);
 
 out_free:

@@ -1303,6 +1303,7 @@ int do_execve(char * filename,
 	retval = mutex_lock_interruptible(&current->cred_exec_mutex);
 	if (retval < 0)
 		goto out_free;
+	current->in_execve = 1;
 
 	retval = -ENOMEM;
 	bprm->cred = prepare_exec_creds();

@@ -1356,6 +1357,7 @@ int do_execve(char * filename,
 		goto out;
 
 	/* execve succeeded */
+	current->in_execve = 0;
 	mutex_unlock(&current->cred_exec_mutex);
 	acct_update_integrals(current);
 	free_bprm(bprm);

@@ -1374,6 +1376,7 @@ out_file:
 	}
 
 out_unlock:
+	current->in_execve = 0;
 	mutex_unlock(&current->cred_exec_mutex);
 
 out_free:

@@ -1089,6 +1089,8 @@ struct task_struct {
 	/* ??? */
 	unsigned int personality;
 	unsigned did_exec:1;
+	unsigned in_execve:1;	/* Tell the LSMs that the process is doing an
+				 * execve */
 	pid_t pid;
 	pid_t tgid;
 

@@ -0,0 +1,81 @@
+#ifndef _LINUX_LIST1_H
+#define _LINUX_LIST1_H
+
+#include <linux/list.h>
+#include <linux/rcupdate.h>
+
+/*
+ * Singly linked list implementation.
+ *
+ * This list supports only two operations.
+ * (1) Append an entry to the tail of the list.
+ * (2) Read all entries starting from the head of the list.
+ *
+ * This list is designed for holding "write once, read many" entries.
+ * This list requires no locks for read operation.
+ * This list doesn't support "remove an entry from the list" operation.
+ */
+
+/* To reduce memory usage, this list doesn't use "->prev" pointer. */
+struct list1_head {
+	struct list1_head *next;
+};
+
+#define LIST1_HEAD_INIT(name) { &(name) }
+#define LIST1_HEAD(name) struct list1_head name = LIST1_HEAD_INIT(name)
+
+static inline void INIT_LIST1_HEAD(struct list1_head *list)
+{
+	list->next = list;
+}
+
+/* Reuse list_entry because it doesn't use "->prev" pointer. */
+#define list1_entry list_entry
+
+/* Reuse list_for_each_rcu because it doesn't use "->prev" pointer. */
+#define list1_for_each list_for_each_rcu
+/* Reuse list_for_each_entry_rcu because it doesn't use "->prev" pointer. */
+#define list1_for_each_entry list_for_each_entry_rcu
+
+/**
+ * list1_for_each_cookie - iterate over a list with cookie.
+ * @pos:        the &struct list1_head to use as a loop cursor.
+ * @cookie:     the &struct list1_head to use as a cookie.
+ * @head:       the head for your list.
+ *
+ * Same with list_for_each_rcu() except that this primitive uses @cookie
+ * so that we can continue iteration.
+ * @cookie must be NULL when iteration starts, and @cookie will become
+ * NULL when iteration finishes.
+ *
+ * Since list elements are never removed, we don't need to get a lock
+ * or a reference count.
+ */
+#define list1_for_each_cookie(pos, cookie, head)                      \
+	for (({ if (!cookie)                                          \
+				     cookie = head; }),               \
+	     pos = rcu_dereference((cookie)->next);                   \
+	     prefetch(pos->next), pos != (head) || ((cookie) = NULL); \
+	     (cookie) = pos, pos = rcu_dereference(pos->next))
+
+/**
+ * list1_add_tail - add a new entry to list1 list.
+ * @new: new entry to be added.
+ * @head: list head to add it before.
+ *
+ * Same with list_add_tail_rcu() without "->prev" pointer.
+ *
+ * Caller must hold a lock for protecting @head.
+ */
+static inline void list1_add_tail(struct list1_head *new,
+				  struct list1_head *head)
+{
+	struct list1_head *prev = head;
+
+	new->next = head;
+	while (prev->next != head)
+		prev = prev->next;
+	rcu_assign_pointer(prev->next, new);
+}
+
+#endif

@@ -33,6 +33,7 @@
 #include <linux/swap.h>
 #include <linux/bootmem.h>
 #include <linux/backing-dev.h>
+#include <linux/magic.h>
 #include "internal.h"
 
 

@@ -1972,6 +1973,84 @@ Elong:
 }
 
 /**
+ * d_realpath - Get the realpath of a dentry.
+ *
+ * @path: Pointer to "struct path".
+ * @buffer: Pointer to buffer to return value in.
+ * @buflen: Sizeof @buffer.
+ *
+ * Returns pointer to the realpath on success, an error code othersize.
+ *
+ * If @dentry is a directory, trailing '/' is appended.
+ * If /proc/PID/ is replaced by /proc/self/ if PID == current->tgid.
+ */
+char *d_realpath(struct path *path, char *buffer, int buflen)
+{
+	struct dentry *dentry = path->dentry;
+	struct vfsmount *vfsmnt = path->mnt;
+	char *end = buffer + buflen;
+	char self_pid[16];
+
+	snprintf(self_pid, sizeof(self_pid), "%u", current->tgid);
+	spin_lock(&dcache_lock);
+	spin_lock(&vfsmount_lock);
+	if (buflen < 1 || prepend(&end, &buflen, "", 1))
+		goto Elong;
+	/*
+	 * Exception: Add trailing '/' for directory.
+	 */
+	if (dentry->d_inode && S_ISDIR(dentry->d_inode->i_mode) &&
+	    prepend(&end, &buflen, "/", 1))
+		goto Elong;
+	for (;;) {
+		struct dentry *parent;
+		const char *name;
+
+		if (dentry == vfsmnt->mnt_root || IS_ROOT(dentry)) {
+			/* Global root? */
+			if (vfsmnt->mnt_parent == vfsmnt)
+				break;
+			dentry = vfsmnt->mnt_mountpoint;
+			vfsmnt = vfsmnt->mnt_parent;
+			continue;
+		}
+		parent = dentry->d_parent;
+		prefetch(parent);
+		/*
+		 * Exception: Use /proc/self/ rather than /proc/\$/
+		 * for current process.
+		 */
+		name = dentry->d_name.name;
+		if (IS_ROOT(parent) &&
+		    parent->d_sb->s_magic == PROC_SUPER_MAGIC &&
+		    !strcmp(name, self_pid)) {
+			if (prepend(&end, &buflen, "self", 4))
+				goto Elong;
+		} else {
+			if (prepend_name(&end, &buflen, &dentry->d_name))
+				goto Elong;
+		}
+		if (prepend(&end, &buflen, "/", 1))
+			goto Elong;
+		dentry = parent;
+	}
+	if (*end == '/') {
+		/* hit the slash */
+		buflen++;
+		end++;
+	}
+	if (prepend_name(&end, &buflen, &dentry->d_name))
+		goto Elong;
+ out:
+	spin_unlock(&vfsmount_lock);
+	spin_unlock(&dcache_lock);
+	return end;
+ Elong:
+	end = ERR_PTR(-ENAMETOOLONG);
+	goto out;
+}
+
+/**
  * d_path - return the path of a dentry
  * @path: path to report
  * @buf: buffer to return value in

@@ -304,6 +304,7 @@ extern char *dynamic_dname(struct dentry
 extern char *__d_path(const struct path *path, struct path *root, char *, int);
 extern char *d_path(const struct path *, char *, int);
 extern char *dentry_path(struct dentry *, char *, int);
+extern char *d_realpath(struct path *, char *, int);
 
 /* Allocation counts.. */
 

@@ -0,0 +1,540 @@
+/*
+ * security/tomoyo/realpath.c
+ *
+ * Get the canonicalized absolute pathnames. The basis for TOMOYO.
+ *
+ * Copyright (C) 2005-2008  NTT DATA CORPORATION
+ *
+ * Version: 2.2.0-pre   2008/10/10
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/mount.h>
+#include <linux/magic.h>
+#include <linux/sysctl.h>
+#include "common.h"
+#include "realpath.h"
+
+/**
+ * tmy_realpath_from_path2 - Returns realpath(3) of the given dentry but ignores chroot'ed root.
+ *
+ * @path:        Pointer to "struct path".
+ * @newname:     Pointer to buffer to return value in.
+ * @newname_len: Size of @newname.
+ *
+ * Returns 0 on success, negative value otherwise.
+ *
+ * If dentry is a directory, trailing '/' is appended.
+ * Characters out of 0x20 < c < 0x7F range are converted to
+ * \ooo style octal string.
+ * Character \ is converted to \\ string.
+ */
+int tmy_realpath_from_path2(struct path *path, char *newname, int newname_len)
+{
+	int error = -ENOMEM;
+	struct dentry *dentry = path->dentry;
+	char *sp;
+
+	if (!dentry || !path->mnt || !newname || newname_len <= 2048)
+		return -EINVAL;
+	if (dentry->d_op && dentry->d_op->d_dname) {
+		/* For "socket:[\$]" and "pipe:[\$]". */
+		static const int offset = 1536;
+		sp = dentry->d_op->d_dname(dentry, newname + offset,
+					   newname_len - offset);
+	} else {
+		path_get(path);
+		sp = d_realpath(path, newname, newname_len);
+		path_put(path);
+	}
+	if (IS_ERR(sp)) {
+		error = PTR_ERR(sp);
+	} else {
+		char *dp = newname;
+		newname += newname_len - 5;
+		while (dp <= newname) {
+			const unsigned char c = *(unsigned char *) sp++;
+			*dp++ = c;
+			if (c == '\\') {
+				*dp++ = '\\';
+			} else if (c > ' ' && c < 127) {
+				continue;
+			} else if (!c) {
+				error = 0;
+				break;
+			} else {
+				*dp++ = '\\';
+				*dp++ = (c >> 6) + '0';
+				*dp++ = ((c >> 3) & 7) + '0';
+				*dp++ = (c & 7) + '0';
+			}
+		}
+	}
+	if (error)
+		printk(KERN_WARNING "tmy_realpath: Pathname too long.\n");
+	return error;
+}
+
+/**
+ * tmy_realpath_from_path - Returns realpath(3) of the given pathname but ignores chroot'ed root.
+ *
+ * @path: Pointer to "struct path".
+ *
+ * Returns the realpath of the given @path on success, NULL otherwise.
+ *
+ * These functions use tmy_alloc(), so the caller must call tmy_free()
+ * if these functions didn't return NULL.
+ */
+char *tmy_realpath_from_path(struct path *path)
+{
+	char *buf = tmy_alloc(sizeof(struct tmy_page_buffer));
+
+	if (buf && tmy_realpath_from_path2(path, buf,
+					     TMY_MAX_PATHNAME_LEN - 1) == 0)
+		return buf;
+	tmy_free(buf);
+	return NULL;
+}
+
+/**
+ * tmy_realpath - Get realpath of a pathname.
+ *
+ * @pathname: The pathname to solve.
+ *
+ * Returns the realpath of @pathname on success, NULL otherwise.
+ */
+char *tmy_realpath(const char *pathname)
+{
+	struct nameidata nd;
+
+	if (pathname && path_lookup(pathname, LOOKUP_FOLLOW, &nd) == 0) {
+		char *buf = tmy_realpath_from_path(&nd.path);
+		path_put(&nd.path);
+		return buf;
+	}
+	return NULL;
+}
+
+/**
+ * tmy_realpath_nofollow - Get realpath of a pathname.
+ *
+ * @pathname: The pathname to solve.
+ *
+ * Returns the realpath of @pathname on success, NULL otherwise.
+ */
+char *tmy_realpath_nofollow(const char *pathname)
+{
+	struct nameidata nd;
+
+	if (pathname && path_lookup(pathname, 0, &nd) == 0) {
+		char *buf = tmy_realpath_from_path(&nd.path);
+		path_put(&nd.path);
+		return buf;
+	}
+	return NULL;
+}
+
+/**
+ * round_up - Round up an integer so that the returned pointers are appropriately aligned.
+ *
+ * @size: Size in bytes.
+ *
+ * Returns rounded value of @size.
+ *
+ * FIXME: Are there more requirements that is needed for assigning value
+ * atomically?
+ */
+static inline unsigned int round_up(const unsigned int size)
+{
+	if (sizeof(void *) >= sizeof(long))
+		return ((size + sizeof(void *) - 1)
+			/ sizeof(void *)) * sizeof(void *);
+	else
+		return ((size + sizeof(long) - 1)
+			/ sizeof(long)) * sizeof(long);
+}
+
+/* Memory allocated for non-string data. */
+static unsigned int allocated_memory_for_elements;
+/* Quota for holding non-string data. */
+static unsigned int quota_for_elements;
+
+/**
+ * tmy_alloc_element - Allocate permanent memory for structures.
+ *
+ * @size: Size in bytes.
+ *
+ * Returns pointer to allocated memory on success, NULL otherwise.
+ *
+ * The RAM is chunked, so NEVER try to kfree() the returned pointer.
+ */
+void *tmy_alloc_element(const unsigned int size)
+{
+	static char *buf;
+	static DEFINE_MUTEX(lock);
+	static unsigned int buf_used_len = PAGE_SIZE;
+	char *ptr = NULL;
+	const unsigned int word_aligned_size = round_up(size);
+
+	if (word_aligned_size > PAGE_SIZE)
+		return NULL;
+	/***** EXCLUSIVE SECTION START *****/
+	mutex_lock(&lock);
+	if (buf_used_len + word_aligned_size > PAGE_SIZE) {
+		if (!quota_for_elements || allocated_memory_for_elements
+		    + PAGE_SIZE <= quota_for_elements)
+			ptr = kzalloc(PAGE_SIZE, GFP_KERNEL);
+		if (!ptr) {
+			printk(KERN_WARNING "ERROR: Out of memory "
+			       "for tmy_alloc_element().\n");
+			if (!sbin_init_started)
+				panic("MAC Initialization failed.\n");
+		} else {
+			buf = ptr;
+			allocated_memory_for_elements += PAGE_SIZE;
+			buf_used_len = word_aligned_size;
+			ptr = buf;
+		}
+	} else if (word_aligned_size) {
+		int i;
+		ptr = buf + buf_used_len;
+		buf_used_len += word_aligned_size;
+		for (i = 0; i < word_aligned_size; i++) {
+			if (!ptr[i])
+				continue;
+			printk(KERN_ERR "WARNING: Reserved memory was tainted! "
+			       "The system might go wrong.\n");
+			ptr[i] = '\0';
+		}
+	}
+	mutex_unlock(&lock);
+	/***** EXCLUSIVE SECTION END *****/
+	return ptr;
+}
+
+/* Memory allocated for string data. */
+static unsigned int allocated_memory_for_savename;
+/* Quota for holding string data. */
+static unsigned int quota_for_savename;
+
+/*
+ * TOMOYO uses this hash only when appending a string into the string
+ * table. Frequency of appending strings is very low. So we don't need
+ * large (e.g. 64k) hash size. 256 will be sufficient.
+ */
+#define MAX_HASH 256
+
+/* Structure for string data. */
+struct name_entry {
+	struct list1_head list;
+	struct path_info entry;
+};
+
+/* Structure for available memory region. */
+struct free_memory_block_list {
+	struct list_head list;
+	char *ptr;             /* Pointer to a free area. */
+	int len;               /* Length of the area.     */
+};
+
+/*
+ * The list for "struct name_entry".
+ *
+ * This list is updated only inside tmy_save_name(), thus
+ * no global mutex exists.
+ */
+static struct list1_head name_list[MAX_HASH];
+
+/**
+ * tmy_save_name - Allocate permanent memory for string data.
+ *
+ * @name: The string to store into the permernent memory.
+ *
+ * Returns pointer to "struct path_info" on success, NULL otherwise.
+ *
+ * The RAM is shared, so NEVER try to modify or kfree() the returned name.
+ */
+const struct path_info *tmy_save_name(const char *name)
+{
+	static LIST_HEAD(fmb_list);
+	static DEFINE_MUTEX(lock);
+	struct name_entry *ptr;
+	unsigned int hash;
+	struct free_memory_block_list *fmb;
+	int len;
+	char *cp;
+
+	if (!name)
+		return NULL;
+	len = strlen(name) + 1;
+	if (len > TMY_MAX_PATHNAME_LEN) {
+		printk(KERN_WARNING "ERROR: Name too long "
+		       "for tmy_save_name().\n");
+		return NULL;
+	}
+	hash = full_name_hash((const unsigned char *) name, len - 1);
+	/***** EXCLUSIVE SECTION START *****/
+	mutex_lock(&lock);
+	list1_for_each_entry(ptr, &name_list[hash % MAX_HASH], list) {
+		if (hash == ptr->entry.hash && !strcmp(name, ptr->entry.name))
+			goto out;
+	}
+	list_for_each_entry(fmb, &fmb_list, list) {
+		if (len <= fmb->len)
+			goto ready;
+	}
+	if (!quota_for_savename || allocated_memory_for_savename + PAGE_SIZE
+	    <= quota_for_savename)
+		cp = kzalloc(PAGE_SIZE, GFP_KERNEL);
+	else
+		cp = NULL;
+	fmb = kzalloc(sizeof(*fmb), GFP_KERNEL);
+	if (!cp || !fmb) {
+		kfree(cp);
+		kfree(fmb);
+		printk(KERN_WARNING "ERROR: Out of memory "
+		       "for tmy_save_name().\n");
+		if (!sbin_init_started)
+			panic("MAC Initialization failed.\n");
+		ptr = NULL;
+		goto out;
+	}
+	allocated_memory_for_savename += PAGE_SIZE;
+	list_add(&fmb->list, &fmb_list);
+	fmb->ptr = cp;
+	fmb->len = PAGE_SIZE;
+ready:
+	ptr = tmy_alloc_element(sizeof(*ptr));
+	if (!ptr)
+		goto out;
+	ptr->entry.name = fmb->ptr;
+	memmove(fmb->ptr, name, len);
+	tmy_fill_path_info(&ptr->entry);
+	fmb->ptr += len;
+	fmb->len -= len;
+	list1_add_tail(&ptr->list, &name_list[hash % MAX_HASH]);
+	if (fmb->len == 0) {
+		list_del(&fmb->list);
+		kfree(fmb);
+	}
+out:
+	mutex_unlock(&lock);
+	/***** EXCLUSIVE SECTION END *****/
+	return ptr ? &ptr->entry : NULL;
+}
+
+/**
+ * tmy_realpath_init - Initialize realpath related code.
+ *
+ * Returns 0.
+ */
+static int __init tmy_realpath_init(void)
+{
+	int i;
+
+	if (TMY_MAX_PATHNAME_LEN > PAGE_SIZE)
+		panic("Bad size.");
+	for (i = 0; i < MAX_HASH; i++)
+		INIT_LIST1_HEAD(&name_list[i]);
+	INIT_LIST1_HEAD(&KERNEL_DOMAIN.acl_info_list);
+	KERNEL_DOMAIN.domainname = tmy_save_name(ROOT_NAME);
+	list1_add_tail(&KERNEL_DOMAIN.list, &domain_list);
+	if (tmy_find_domain(ROOT_NAME) != &KERNEL_DOMAIN)
+		panic("Can't register KERNEL_DOMAIN");
+	return 0;
+}
+
+security_initcall(tmy_realpath_init);
+
+/* Memory allocated for temporal purpose. */
+static atomic_t dynamic_memory_size;
+
+/**
+ * tmy_alloc - Allocate memory for temporal purpose.
+ *
+ * @size: Size in bytes.
+ *
+ * Returns pointer to allocated memory on success, NULL otherwise.
+ */
+void *tmy_alloc(const size_t size)
+{
+	void *p = kzalloc(size, GFP_KERNEL);
+	if (p)
+		atomic_add(ksize(p), &dynamic_memory_size);
+	return p;
+}
+
+/**
+ * tmy_free - Release memory allocated by tmy_alloc().
+ *
+ * @p: Pointer returned by tmy_alloc(). May be NULL.
+ *
+ * Returns nothing.
+ */
+void tmy_free(const void *p)
+{
+	if (p)
+		atomic_sub(ksize(p), &dynamic_memory_size);
+	kfree(p);
+}
+
+static int tmy_print_ascii(const char *sp, const char *cp,
+			   int *buflen0, char **end0)
+{
+	int error = -ENOMEM;
+	int buflen = *buflen0;
+	char *end = *end0;
+
+	while (sp <= cp) {
+		unsigned char c;
+
+		c = *(unsigned char *) cp;
+		if (c == '\\') {
+			buflen -= 2;
+			if (buflen < 0)
+				goto out;
+			*--end = '\\';
+			*--end = '\\';
+		} else if (c > ' ' && c < 127) {
+			if (--buflen < 0)
+				goto out;
+			*--end = (char) c;
+		} else {
+			buflen -= 4;
+			if (buflen < 0)
+				goto out;
+			*--end = (c & 7) + '0';
+			*--end = ((c >> 3) & 7) + '0';
+			*--end = (c >> 6) + '0';
+			*--end = '\\';
+		}
+		cp--;
+	}
+
+	*buflen0 = buflen;
+	*end0 = end;
+	error = 0;
+out:
+	return error;
+}
+
+
+/* tmy_realpath_from_path2() for "struct ctl_table". */
+static int tmy_sysctl_path(struct ctl_table *table, char *buffer, int buflen)
+{
+	int error = -ENOMEM;
+	char *end = buffer + buflen;
+
+	if (buflen < 256)
+		goto out;
+
+	*--end = '\0';
+	buflen--;
+
+	buflen -= 9; /* for "/proc/sys" prefix */
+
+	while (table) {
+		char buf[32];
+		const char *sp = table->procname;
+		const char *cp;
+
+		if (!sp) {
+			memset(buf, 0, sizeof(buf));
+			snprintf(buf, sizeof(buf) - 1, "=%d=", table->ctl_name);
+			sp = buf;
+		}
+		cp = strchr(sp, '\0') - 1;
+
+		if (tmy_print_ascii(sp, cp, &buflen, &end))
+			goto out;
+
+		if (--buflen < 0)
+			goto out;
+
+		*--end = '/';
+		table = table->parent;
+	}
+
+	/* Move the pathname to the top of the buffer. */
+	memmove(buffer, "/proc/sys", 9);
+	memmove(buffer + 9, end, strlen(end) + 1);
+	error = 0;
+out:
+	return error;
+}
+
+/**
+ * sysctlpath_from_table - return the realpath of a ctl_table.
+ * @table: pointer to "struct ctl_table".
+ *
+ * Returns realpath(3) of the @table on success.
+ * Returns NULL on failure.
+ *
+ * This function uses tmy_alloc(), so the caller must call tmy_free()
+ * if this function didn't return NULL.
+ */
+char *sysctlpath_from_table(struct ctl_table *table)
+{
+	char *buf = tmy_alloc(TMY_MAX_PATHNAME_LEN);
+
+	if (buf && tmy_sysctl_path(table, buf, TMY_MAX_PATHNAME_LEN - 1) == 0)
+		return buf;
+	tmy_free(buf);
+	return NULL;
+}
+
+/**
+ * tmy_read_memory_counter - Check for memory usage.
+ *
+ * @head: Pointer to "struct tmy_io_buffer".
+ *
+ * Returns memory usage.
+ */
+int tmy_read_memory_counter(struct tmy_io_buffer *head)
+{
+	if (!head->read_eof) {
+		const unsigned int shared = allocated_memory_for_savename;
+		const unsigned int private = allocated_memory_for_elements;
+		const unsigned int dynamic = atomic_read(&dynamic_memory_size);
+		char buffer[64];
+
+		memset(buffer, 0, sizeof(buffer));
+		if (quota_for_savename)
+			snprintf(buffer, sizeof(buffer) - 1,
+				 "   (Quota: %10u)", quota_for_savename);
+		else
+			buffer[0] = '\0';
+		tmy_io_printf(head, "Shared:  %10u%s\n", shared, buffer);
+		if (quota_for_elements)
+			snprintf(buffer, sizeof(buffer) - 1,
+				 "   (Quota: %10u)", quota_for_elements);
+		else
+			buffer[0] = '\0';
+		tmy_io_printf(head, "Private: %10u%s\n", private, buffer);
+		tmy_io_printf(head, "Dynamic: %10u\n", dynamic);
+		tmy_io_printf(head, "Total:   %10u\n",
+			      shared + private + dynamic);
+		head->read_eof = true;
+	}
+	return 0;
+}
+
+/**
+ * tmy_write_memory_quota - Set memory quota.
+ *
+ * @head: Pointer to "struct tmy_io_buffer".
+ *
+ * Returns 0.
+ */
+int tmy_write_memory_quota(struct tmy_io_buffer *head)
+{
+	char *data = head->write_buf;
+	unsigned int size;
+
+	if (sscanf(data, "Shared: %u", &size) == 1)
+		quota_for_savename = size;
+	else if (sscanf(data, "Private: %u", &size) == 1)
+		quota_for_elements = size;
+	return 0;
+}

60 lines not on this page · raw message

@@ -0,0 +1,2209 @@
+/*
+ * security/tomoyo/common.c
+ *
+ * Common functions for TOMOYO.
+ *
+ * Copyright (C) 2005-2008  NTT DATA CORPORATION
+ *
+ * Version: 2.2.0-pre   2008/10/10
+ *
+ */
+
+#include <linux/uaccess.h>
+#include <linux/security.h>
+#include <linux/hardirq.h>
+#include "realpath.h"
+#include "common.h"
+#include "tomoyo.h"
+
+/* Set default specified by the kernel config. */
+#define MAX_ACCEPT_ENTRY 2048
+
+/* Has /sbin/init started? */
+bool sbin_init_started;
+
+/* String table for functionality that takes 4 modes. */
+static const char *mode_4[4] = {
+	"disabled", "learning", "permissive", "enforcing"
+};
+/* String table for functionality that takes 2 modes. */
+static const char *mode_2[4] = {
+	"disabled", "enabled", "enabled", "enabled"
+};
+
+/* Table for profile. */
+static struct {
+	const char *keyword;
+	unsigned int current_value;
+	const unsigned int max_value;
+} tmy_control_array[TMY_MAX_CONTROL_INDEX] = {
+	[TMY_TOMOYO_MAC_FOR_FILE]        = { "MAC_FOR_FILE",        0, 3 },
+	[TMY_TOMOYO_MAX_ACCEPT_ENTRY]
+	= { "MAX_ACCEPT_ENTRY",    MAX_ACCEPT_ENTRY, INT_MAX },
+	[TMY_TOMOYO_VERBOSE]             = { "TOMOYO_VERBOSE",      1, 1 },
+};
+
+/* Profile table. Memory is allocated as needed. */
+static struct profile {
+	unsigned int value[TMY_MAX_CONTROL_INDEX];
+	const struct path_info *comment;
+} *profile_ptr[MAX_PROFILES];
+
+/* Permit policy management by non-root user? */
+static bool manage_by_non_root;
+
+/* Utility functions. */
+
+/* Open operation for /sys/kernel/security/tomoyo/ interface. */
+static int tmy_open_control(const u8 type, struct file *file);
+/* Close /sys/kernel/security/tomoyo/ interface. */
+static int tmy_close_control(struct file *file);
+/* Read operation for /sys/kernel/security/tomoyo/ interface. */
+static int tmy_read_control(struct file *file, char __user *buffer,
+			    const int buffer_len);
+/* Write operation for /sys/kernel/security/tomoyo/ interface. */
+static int tmy_write_control(struct file *file, const char __user *buffer,
+			     const int buffer_len);
+
+/**
+ * is_byte_range - Check whether the string isa \ooo style octal value.
+ *
+ * @str: Pointer to the string.
+ *
+ * Returns true if @str is a \ooo style octal value, false otherwise.
+ */
+static bool is_byte_range(const char *str)
+{
+	return *str >= '0' && *str++ <= '3' &&
+		*str >= '0' && *str++ <= '7' &&
+		*str >= '0' && *str <= '7';
+}
+
+/**
+ * is_decimal - Check whether the character is a decimal character.
+ *
+ * @c: The character to check.
+ *
+ * Returns true if @c is a decimal character, false otherwise.
+ */
+static bool is_decimal(const char c)
+{
+	return c >= '0' && c <= '9';
+}
+
+/**
+ * is_hexadecimal - Check whether the character is a hexadecimal character.
+ *
+ * @c: The character to check.
+ *
+ * Returns true if @c is a hexadecimal character, false otherwise.
+ */
+static bool is_hexadecimal(const char c)
+{
+	return (c >= '0' && c <= '9') ||
+		(c >= 'A' && c <= 'F') ||
+		(c >= 'a' && c <= 'f');
+}
+
+/**
+ * is_alphabet_char - Check whether the character is an alphabet.
+ *
+ * @c: The character to check.
+ *
+ * Returns true if @c is an alphabet character, false otherwise.
+ */
+static bool is_alphabet_char(const char c)
+{
+	return (c >= 'A' && c <= 'F') || (c >= 'a' && c <= 'f');
+}
+
+/**
+ * make_byte - Make byte value from three octal characters.
+ *
+ * @c1: The first character.
+ * @c2: The second character.
+ * @c3: The third character.
+ *
+ * Returns byte value.
+ */
+static u8 make_byte(const u8 c1, const u8 c2, const u8 c3)
+{
+	return ((c1 - '0') << 6) + ((c2 - '0') << 3) + (c3 - '0');
+}
+
+/**
+ * str_starts - Check whether the given string starts with the given keyword.
+ *
+ * @src:  Pointer to pointer to the string.
+ * @find: Pointer to the keyword.
+ *
+ * Returns true if @src starts with @find, false otherwise.
+ *
+ * The @src is updated to point the first character after the @find
+ * if @src starts with @find.
+ */
+static bool str_starts(char **src, const char *find)
+{
+	const int len = strlen(find);
+	char *tmp = *src;
+
+	if (strncmp(tmp, find, len))
+		return false;
+	tmp += len;
+	*src = tmp;
+	return true;
+}
+
+/**
+ * normalize_line - Format string.
+ *
+ * @buffer: The line to normalize.
+ *
+ * Leading and trailing whitespaces are removed.
+ * Multiple whitespaces are packed into single space.
+ *
+ * Returns nothing.
+ */
+static void normalize_line(unsigned char *buffer)
+{
+	unsigned char *sp = buffer;
+	unsigned char *dp = buffer;
+	bool first = true;
+
+	while (*sp && (*sp <= ' ' || *sp >= 127))
+		sp++;
+	while (*sp) {
+		if (!first)
+			*dp++ = ' ';
+		first = false;
+		while (*sp > ' ' && *sp < 127)
+			*dp++ = *sp++;
+		while (*sp && (*sp <= ' ' || *sp >= 127))
+			sp++;
+	}
+	*dp = '\0';
+}
+
+/**
+ * tmy_is_correct_path - Validate a pathname.
+ * @filename:     The pathname to check.
+ * @start_type:   Should the pathname start with '/'?
+ *                1 = must / -1 = must not / 0 = don't care
+ * @pattern_type: Can the pathname contain a wildcard?
+ *                1 = must / -1 = must not / 0 = don't care
+ * @end_type:     Should the pathname end with '/'?
+ *                1 = must / -1 = must not / 0 = don't care
+ * @function:     The name of function calling me.
+ *
+ * Check whether the given filename follows the naming rules.
+ * Returns true if @filename follows the naming rules, false otherwise.
+ */
+bool tmy_is_correct_path(const char *filename, const s8 start_type,
+			 const s8 pattern_type, const s8 end_type,
+			 const char *function)
+{
+	bool contains_pattern = false;
+	unsigned char c;
+	unsigned char d;
+	unsigned char e;
+	const char *original_filename = filename;
+
+	if (!filename)
+		goto out;
+	c = *filename;
+	if (start_type == 1) { /* Must start with '/' */
+		if (c != '/')
+			goto out;
+	} else if (start_type == -1) { /* Must not start with '/' */
+		if (c == '/')
+			goto out;
+	}
+	if (c)
+		c = *(strchr(filename, '\0') - 1);
+	if (end_type == 1) { /* Must end with '/' */
+		if (c != '/')
+			goto out;
+	} else if (end_type == -1) { /* Must not end with '/' */
+		if (c == '/')
+			goto out;
+	}
+	while ((c = *filename++) != '\0') {
+		if (c == '\\') {
+			switch ((c = *filename++)) {
+			case '\\':  /* "\\" */
+				continue;
+			case '$':   /* "\$" */
+			case '+':   /* "\+" */
+			case '?':   /* "\?" */
+			case '*':   /* "\*" */
+			case '@':   /* "\@" */
+			case 'x':   /* "\x" */
+			case 'X':   /* "\X" */
+			case 'a':   /* "\a" */
+			case 'A':   /* "\A" */
+			case '-':   /* "\-" */
+				if (pattern_type == -1)
+					break; /* Must not contain pattern */
+				contains_pattern = true;
+				continue;
+			case '0':   /* "\ooo" */
+			case '1':
+			case '2':
+			case '3':
+				d = *filename++;
+				if (d < '0' || d > '7')
+					break;
+				e = *filename++;
+				if (e < '0' || e > '7')
+					break;
+				c = make_byte(c, d, e);
+				if (c && (c <= ' ' || c >= 127))
+					continue; /* pattern is not \000 */
+			}
+			goto out;
+		} else if (c <= ' ' || c >= 127) {
+			goto out;
+		}
+	}
+	if (pattern_type == 1) { /* Must contain pattern */
+		if (!contains_pattern)
+			goto out;
+	}
+	return true;
+out:
+	printk(KERN_DEBUG "%s: Invalid pathname '%s'\n", function,
+	       original_filename);
+	return false;
+}
+
+/**
+ * tmy_is_correct_domain - Check whether the given domainname follows the naming rules.
+ * @domainname:   The domainname to check.
+ * @function:     The name of function calling me.
+ *
+ * Returns true if @domainname follows the naming rules, false otherwise.
+ */
+bool tmy_is_correct_domain(const unsigned char *domainname,
+			   const char *function)
+{
+	unsigned char c;
+	unsigned char d;
+	unsigned char e;
+	const char *org_domainname = domainname;
+
+	if (!domainname || strncmp(domainname, ROOT_NAME, ROOT_NAME_LEN))
+		goto out;
+	domainname += ROOT_NAME_LEN;
+	if (!*domainname)
+		return true;
+	do {
+		if (*domainname++ != ' ')
+			goto out;
+		if (*domainname++ != '/')
+			goto out;
+		while ((c = *domainname) != '\0' && c != ' ') {
+			domainname++;
+			if (c == '\\') {
+				c = *domainname++;
+				switch ((c)) {
+				case '\\':  /* "\\" */
+					continue;
+				case '0':   /* "\ooo" */
+				case '1':
+				case '2':
+				case '3':
+					d = *domainname++;
+					if (d < '0' || d > '7')
+						break;
+					e = *domainname++;
+					if (e < '0' || e > '7')
+						break;
+					c = make_byte(c, d, e);
+					if (c && (c <= ' ' || c >= 127))
+						/* pattern is not \000 */
+						continue;
+				}
+				goto out;
+			} else if (c < ' ' || c >= 127) {
+				goto out;
+			}
+		}
+	} while (*domainname);
+	return true;
+out:
+	printk(KERN_DEBUG "%s: Invalid domainname '%s'\n", function,
+	       org_domainname);
+	return false;
+}
+
+/**
+ * tmy_is_domain_def - Check whether the given token can be a domainname.
+ *
+ * @buffer: The token to check.
+ *
+ * Returns true if @buffer possibly be a domainname, false otherwise.
+ */
+bool tmy_is_domain_def(const unsigned char *buffer)
+{
+	return !strncmp(buffer, ROOT_NAME, ROOT_NAME_LEN);
+}
+
+/**
+ * tmy_find_domain - Find a domain by the given name.
+ *
+ * @domainname: The domainname to find.
+ *
+ * Returns pointer to "struct domain_info" if found, NULL otherwise.
+ */
+struct domain_info *tmy_find_domain(const char *domainname)
+{
+	struct domain_info *domain;
+	struct path_info name;
+
+	name.name = domainname;
+	tmy_fill_path_info(&name);
+	list1_for_each_entry(domain, &domain_list, list) {
+		if (!domain->is_deleted &&
+		    !tmy_pathcmp(&name, domain->domainname))
+			return domain;
+	}
+	return NULL;
+}
+
+/**
+ * path_depth - Evaluate the number of '/' in a string.
+ *
+ * @pathname: The string to evaluate.
+ *
+ * Returns path depth of the string.
+ *
+ * I score 2 for each of the '/' in the @pathname
+ * and score 1 if the @pathname ends with '/'.
+ */
+static int path_depth(const char *pathname)
+{
+	int i = 0;
+
+	if (pathname) {
+		char *ep = strchr(pathname, '\0');
+		if (pathname < ep--) {
+			if (*ep != '/')
+				i++;
+			while (pathname <= ep)
+				if (*ep-- == '/')
+					i += 2;
+		}
+	}
+	return i;
+}
+
+/**
+ * const_part_length - Evaluate the initial length without a pattern in a token.
+ *
+ * @filename: The string to evaluate.
+ *
+ * Returns the initial length without a pattern in @filename.
+ */
+static int const_part_length(const char *filename)
+{
+	char c;
+	int len = 0;
+
+	if (!filename)
+		return 0;
+	while ((c = *filename++) != '\0') {
+		if (c != '\\') {
+			len++;
+			continue;
+		}
+		c = *filename++;
+		switch (c) {
+		case '\\':  /* "\\" */
+			len += 2;
+			continue;
+		case '0':   /* "\ooo" */
+		case '1':
+		case '2':
+		case '3':
+			c = *filename++;
+			if (c < '0' || c > '7')
+				break;
+			c = *filename++;
+			if (c < '0' || c > '7')
+				break;
+			len += 4;
+			continue;
+		}
+		break;
+	}
+	return len;
+}
+
+/**
+ * tmy_fill_path_info - Fill in "struct path_info" members.
+ *
+ * @ptr: Pointer to "struct path_info" to fill in.
+ *
+ * The caller sets "struct path_info"->name.
+ */
+void tmy_fill_path_info(struct path_info *ptr)
+{
+	const char *name = ptr->name;
+	const int len = strlen(name);
+
+	ptr->total_len = len;
+	ptr->const_len = const_part_length(name);
+	ptr->is_dir = len && (name[len - 1] == '/');
+	ptr->is_patterned = (ptr->const_len < len);
+	ptr->hash = full_name_hash(name, len);
+	ptr->depth = path_depth(name);
+}
+
+/**
+ * file_matches_to_pattern2 - Pattern matching without '/' character
+ * and "\-" pattern.
+ *
+ * @filename:     The start of string to check.
+ * @filename_end: The end of string to check.
+ * @pattern:      The start of pattern to compare.
+ * @pattern_end:  The end of pattern to compare.
+ *
+ * Returns true if @filename matches @pattern, false otherwise.
+ */
+static bool file_matches_to_pattern2(const char *filename,
+				     const char *filename_end,
+				     const char *pattern,
+				     const char *pattern_end)
+{
+	while (filename < filename_end && pattern < pattern_end) {
+		char c;
+		if (*pattern != '\\') {
+			if (*filename++ != *pattern++)
+				return false;
+			continue;
+		}
+		c = *filename;
+		pattern++;
+		switch (*pattern) {
+			int i;
+			int j;
+		case '?':
+			if (c == '/') {
+				return false;
+			} else if (c == '\\') {
+				if (filename[1] == '\\')
+					filename++;
+				else if (is_byte_range(filename + 1))
+					filename += 3;
+				else
+					return false;
+			}
+			break;
+		case '\\':
+			if (c != '\\')
+				return false;
+			if (*++filename != '\\')
+				return false;
+			break;
+		case '+':
+			if (!is_decimal(c))
+				return false;
+			break;
+		case 'x':
+			if (!is_hexadecimal(c))
+				return false;
+			break;
+		case 'a':
+			if (!is_alphabet_char(c))
+				return false;
+			break;
+		case '0':
+		case '1':
+		case '2':
+		case '3':
+			if (c == '\\' && is_byte_range(filename + 1)
+			    && strncmp(filename + 1, pattern, 3) == 0) {
+				filename += 3;
+				pattern += 2;
+				break;
+			}
+			return false; /* Not matched. */
+		case '*':
+		case '@':
+			for (i = 0; i <= filename_end - filename; i++) {
+				if (file_matches_to_pattern2(filename + i,
+							     filename_end,
+							     pattern + 1,
+							     pattern_end))
+					return true;
+				c = filename[i];
+				if (c == '.' && *pattern == '@')
+					break;
+				if (c != '\\')
+					continue;
+				if (filename[i + 1] == '\\')
+					i++;
+				else if (is_byte_range(filename + i + 1))
+					i += 3;
+				else
+					break; /* Bad pattern. */
+			}
+			return false; /* Not matched. */
+		default:
+			j = 0;
+			c = *pattern;
+			if (c == '$') {
+				while (is_decimal(filename[j]))
+					j++;
+			} else if (c == 'X') {
+				while (is_hexadecimal(filename[j]))
+					j++;
+			} else if (c == 'A') {
+				while (is_alphabet_char(filename[j]))
+					j++;
+			}
+			for (i = 1; i <= j; i++) {
+				if (file_matches_to_pattern2(filename + i,
+							     filename_end,
+							     pattern + 1,
+							     pattern_end))
+					return true;
+			}
+			return false; /* Not matched or bad pattern. */
+		}
+		filename++;
+		pattern++;
+	}
+	while (*pattern == '\\' &&
+	       (*(pattern + 1) == '*' || *(pattern + 1) == '@'))
+		pattern += 2;
+	return filename == filename_end && pattern == pattern_end;
+}
+
+/**
+ * file_matches_to_pattern - Pattern matching without without '/' character.
+ *
+ * @filename:     The start of string to check.
+ * @filename_end: The end of string to check.
+ * @pattern:      The start of pattern to compare.
+ * @pattern_end:  The end of pattern to compare.
+ *
+ * Returns true if @filename matches @pattern, false otherwise.
+ */
+static bool file_matches_to_pattern(const char *filename,
+				    const char *filename_end,
+				    const char *pattern,
+				    const char *pattern_end)
+{
+	const char *pattern_start = pattern;
+	bool first = true;
+	bool result;
+
+	while (pattern < pattern_end - 1) {
+		/* Split at "\-" pattern. */
+		if (*pattern++ != '\\' || *pattern++ != '-')
+			continue;
+		result = file_matches_to_pattern2(filename, filename_end,
+						  pattern_start, pattern - 2);
+		if (first)
+			result = !result;
+		if (result)
+			return false;
+		first = false;
+		pattern_start = pattern;
+	}
+	result = file_matches_to_pattern2(filename, filename_end,
+					  pattern_start, pattern_end);
+	return first ? result : !result;
+}
+
+/**
+ * tmy_path_matches_pattern - Check whether the given filename matches the given pattern.
+ * @filename: The filename to check.
+ * @pattern:  The pattern to compare.
+ *
+ * Returns true if matches, false otherwise.
+ *
+ * The following patterns are available.
+ *   \\     \ itself.
+ *   \ooo   Octal representation of a byte.
+ *   \*     More than or equals to 0 character other than '/'.
+ *   \@     More than or equals to 0 character other than '/' or '.'.
+ *   \?     1 byte character other than '/'.
+ *   \$     More than or equals to 1 decimal digit.
+ *   \+     1 decimal digit.
+ *   \X     More than or equals to 1 hexadecimal digit.
+ *   \x     1 hexadecimal digit.
+ *   \A     More than or equals to 1 alphabet character.
+ *   \a     1 alphabet character.
+ *   \-     Subtraction operator.
+ */
+bool tmy_path_matches_pattern(const struct path_info *filename,
+			      const struct path_info *pattern)
+{
+	/*
+	  if (!filename || !pattern)
+	  return false;
+	*/
+	const char *f = filename->name;
+	const char *p = pattern->name;
+	const int len = pattern->const_len;
+
+	/* If @pattern doesn't contain pattern, I can use strcmp(). */
+	if (!pattern->is_patterned)
+		return !tmy_pathcmp(filename, pattern);
+	/* Dont compare if the number of '/' differs. */
+	if (filename->depth != pattern->depth)
+		return false;
+	/* Compare the initial length without patterns. */
+	if (strncmp(f, p, len))
+		return false;
+	f += len;
+	p += len;
+	/* Main loop. Compare each directory component. */
+	while (*f && *p) {
+		const char *f_delimiter = strchr(f, '/');
+		const char *p_delimiter = strchr(p, '/');
+		if (!f_delimiter)
+			f_delimiter = strchr(f, '\0');
+		if (!p_delimiter)
+			p_delimiter = strchr(p, '\0');
+		if (!file_matches_to_pattern(f, f_delimiter, p, p_delimiter))
+			return false;
+		f = f_delimiter;
+		if (*f)
+			f++;
+		p = p_delimiter;
+		if (*p)
+			p++;
+	}
+	/* Ignore trailing "\*" and "\@" in @pattern. */
+	while (*p == '\\' &&
+	       (*(p + 1) == '*' || *(p + 1) == '@'))
+		p += 2;
+	return !*f && !*p;
+}
+
+/**
+ * tmy_io_printf - Transactional printf() to "struct tmy_io_buffer" structure.
+ *
+ * @head: Pointer to "struct tmy_io_buffer".
+ * @fmt:  The printf()'s format string, followed by parameters.
+ *
+ * Returns true on success, false otherwise.
+ *
+ * The snprintf() will truncate, but tmy_io_printf() won't.
+ */
+bool tmy_io_printf(struct tmy_io_buffer *head, const char *fmt, ...)
+{
+	va_list args;
+	int len;
+	int pos = head->read_avail;
+	int size = head->readbuf_size - pos;
+
+	if (size <= 0)
+		return false;
+	va_start(args, fmt);
+	len = vsnprintf(head->read_buf + pos, size, fmt, args);
+	va_end(args);
+	if (pos + len >= head->readbuf_size)
+		return false;
+	head->read_avail += len;
+	return true;
+}
+
+/**
+ * tmy_get_exe - Get tmy_realpath() of current process.
+ *
+ * Returns the tmy_realpath() of current process on success, NULL otherwise.
+ *
+ * This function uses tmy_alloc(), so the caller must call tmy_free()
+ * if this function didn't return NULL.
+ */
+static const char *tmy_get_exe(void)
+{
+	struct mm_struct *mm = current->mm;
+	struct vm_area_struct *vma;
+	const char *cp = NULL;
+
+	if (!mm)
+		return NULL;
+	down_read(&mm->mmap_sem);
+	for (vma = mm->mmap; vma; vma = vma->vm_next) {
+		if ((vma->vm_flags & VM_EXECUTABLE) && vma->vm_file) {
+			cp = tmy_realpath_from_path(&vma->vm_file->f_path);
+			break;
+		}
+	}
+	up_read(&mm->mmap_sem);
+	return cp;
+}
+
+/**
+ * tmy_get_msg - Get warning message.
+ *
+ * @is_enforce: Is it enforcing mode?
+ *
+ * Returns "ERROR" or "WARNING".
+ */
+const char *tmy_get_msg(const bool is_enforce)
+{
+	if (is_enforce)
+		return "ERROR";
+	else
+		return "WARNING";
+}
+
+/**
+ * tmy_check_flags - Check mode for specified functionality.
+ *
+ * @domain: Pointer to "struct domain_info".
+ * @index:  The functionality to check mode.
+ *
+ * Returns the mode of specified functionality.
+ */
+unsigned int tmy_check_flags(const struct domain_info *domain, const u8 index)
+{
+	const u8 profile = domain->profile;
+
+	if (unlikely(in_interrupt())) {
+		static u8 count = 20;
+		if (count) {
+			count--;
+			printk(KERN_ERR "BUG: sleeping function called "
+			       "from invalid context.\n");
+			dump_stack();
+		}
+		return 0;
+	}
+	return sbin_init_started && index < TMY_MAX_CONTROL_INDEX
+#if MAX_PROFILES != 256
+		&& profile < MAX_PROFILES
+#endif
+		&& profile_ptr[profile] ?
+		profile_ptr[profile]->value[index] : 0;
+}
+
+/**
+ * tmy_verbose_mode - Check whether TOMOYO is verbose mode.
+ *
+ * @domain: Pointer to "struct domain_info".
+ *
+ * Returns true if domain policy violation warning should be printed to
+ * console.
+ */
+bool tmy_verbose_mode(const struct domain_info *domain)
+{
+	return tmy_check_flags(domain, TMY_TOMOYO_VERBOSE) != 0;
+}
+
+/**
+ * tmy_check_domain_quota - Check for domain's quota.
+ *
+ * @domain: Pointer to "struct domain_info".
+ *
+ * Returns true if the domain is not exceeded quota, false otherwise.
+ */
+bool tmy_check_domain_quota(struct domain_info * const domain)
+{
+	unsigned int count = 0;
+	struct acl_info *ptr;
+
+	if (!domain)
+		return true;
+	list1_for_each_entry(ptr, &domain->acl_info_list, list) {
+		if (ptr->type & ACL_DELETED)
+			continue;
+		switch (tmy_acl_type2(ptr)) {
+			struct single_path_acl_record *acl1;
+			struct double_path_acl_record *acl2;
+			u16 perm;
+		case TYPE_SINGLE_PATH_ACL:
+			acl1 = container_of(ptr, struct single_path_acl_record,
+					    head);
+			perm = acl1->perm;
+			if (perm & (1 << TMY_TYPE_EXECUTE_ACL))
+				count++;
+			if (perm &
+			    ((1 << TMY_TYPE_READ_ACL) |
+			     (1 << TMY_TYPE_WRITE_ACL)))
+				count++;
+			if (perm & (1 << TMY_TYPE_CREATE_ACL))
+				count++;
+			if (perm & (1 << TMY_TYPE_UNLINK_ACL))
+				count++;
+			if (perm & (1 << TMY_TYPE_MKDIR_ACL))
+				count++;
+			if (perm & (1 << TMY_TYPE_RMDIR_ACL))
+				count++;
+			if (perm & (1 << TMY_TYPE_MKFIFO_ACL))
+				count++;
+			if (perm & (1 << TMY_TYPE_MKSOCK_ACL))
+				count++;
+			if (perm & (1 << TMY_TYPE_MKBLOCK_ACL))
+				count++;
+			if (perm & (1 << TMY_TYPE_MKCHAR_ACL))
+				count++;
+			if (perm & (1 << TMY_TYPE_TRUNCATE_ACL))
+				count++;
+			if (perm & (1 << TMY_TYPE_SYMLINK_ACL))
+				count++;
+			if (perm & (1 << TMY_TYPE_REWRITE_ACL))
+				count++;
+			break;
+		case TYPE_DOUBLE_PATH_ACL:
+			acl2 = container_of(ptr, struct double_path_acl_record,
+					    head);
+			perm = acl2->perm;
+			if (perm & (1 << TMY_TYPE_LINK_ACL))
+				count++;
+			if (perm & (1 << TMY_TYPE_RENAME_ACL))
+				count++;
+			break;
+		}
+	}
+	if (count < tmy_check_flags(domain, TMY_TOMOYO_MAX_ACCEPT_ENTRY))
+		return true;
+	if (!domain->quota_warned) {
+		domain->quota_warned = true;
+		printk(KERN_WARNING "TOMOYO-WARNING: "
+		       "Domain '%s' has so many ACLs to hold. "
+		       "Stopped learning mode.\n", domain->domainname->name);
+	}
+	return false;
+}
+
+/**
+ * tmy_find_or_assign_new_profile - Create a new profile.
+ *
+ * @profile: Profile number to create.
+ *
+ * Returns pointer to "struct profile" on success, NULL otherwise.
+ */
+static struct profile *tmy_find_or_assign_new_profile(const unsigned int
+						      profile)
+{
+	static DEFINE_MUTEX(lock);
+	struct profile *ptr = NULL;
+
+	/***** EXCLUSIVE SECTION START *****/
+	mutex_lock(&lock);
+	if (profile < MAX_PROFILES) {
+		ptr = profile_ptr[profile];
+		if (ptr)
+			goto ok;
+		ptr = tmy_alloc_element(sizeof(*ptr));
+		if (ptr) {
+			int i;
+			for (i = 0; i < TMY_MAX_CONTROL_INDEX; i++)
+				ptr->value[i]
+					= tmy_control_array[i].current_value;
+			mb(); /* Avoid out-of-order execution. */
+			profile_ptr[profile] = ptr;
+		}
+	}
+ok:
+	mutex_unlock(&lock);
+	/***** EXCLUSIVE SECTION END *****/
+	return ptr;
+}
+
+/**
+ * write_profile - Write profile table.
+ *
+ * @head: Pointer to "struct tmy_io_buffer"
+ *
+ * Returns 0 on success, negative value otherwise.
+ */
+static int write_profile(struct tmy_io_buffer *head)
+{
+	char *data = head->write_buf;
+	unsigned int i;
+	unsigned int value;
+	char *cp;
+	struct profile *profile;
+	unsigned long num;
+
+	cp = strchr(data, '-');
+	if (cp)
+		*cp = '\0';
+	if (strict_strtoul(data, 10, &num))
+		return -EINVAL;
+	if (cp)
+		data = cp + 1;
+	profile = tmy_find_or_assign_new_profile(num);
+	if (!profile)
+		return -EINVAL;
+	cp = strchr(data, '=');
+	if (!cp)
+		return -EINVAL;
+	*cp = '\0';
+	tmy_update_counter(TMY_UPDATES_COUNTER_PROFILE);
+	if (!strcmp(data, "COMMENT")) {
+		profile->comment = tmy_save_name(cp + 1);
+		return 0;
+	}
+	for (i = 0; i < TMY_MAX_CONTROL_INDEX; i++) {
+		if (strcmp(data, tmy_control_array[i].keyword))
+			continue;
+		if (sscanf(cp + 1, "%u", &value) != 1) {
+			int j;
+			const char **modes;
+			switch (i) {
+			case TMY_TOMOYO_VERBOSE:
+				modes = mode_2;
+				break;
+			default:
+				modes = mode_4;
+				break;
+			}
+			for (j = 0; j < 4; j++) {
+				if (strcmp(cp + 1, modes[j]))
+					continue;
+				value = j;
+				break;
+			}
+			if (j == 4)
+				return -EINVAL;
+		} else if (value > tmy_control_array[i].max_value) {
+			value = tmy_control_array[i].max_value;
+		}
+		profile->value[i] = value;
+		return 0;
+	}
+	return -EINVAL;
+}
+
+/**
+ * read_profile - Read profile table.
+ *
+ * @head: Pointer to "struct tmy_io_buffer"
+ *
+ * Returns 0.
+ */
+static int read_profile(struct tmy_io_buffer *head)
+{
+	static const int total = TMY_MAX_CONTROL_INDEX + 1;
+	int step;
+
+	if (head->read_eof)
+		return 0;
+	for (step = head->read_step; step < MAX_PROFILES * total; step++) {
+		const u8 index = step / total;
+		u8 type = step % total;
+		const struct profile *profile = profile_ptr[index];
+		head->read_step = step;
+		if (!profile)
+			continue;
+		if (!type) { /* Print profile' comment tag. */
+			if (!tmy_io_printf(head, "%u-COMMENT=%s\n",
+					   index, profile->comment ?
+					   profile->comment->name : ""))
+				break;
+			continue;
+		}
+		type--;
+		if (type < TMY_MAX_CONTROL_INDEX) {
+			const unsigned int value = profile->value[type];
+			const char **modes = NULL;
+			const char *keyword = tmy_control_array[type].keyword;
+			switch (tmy_control_array[type].max_value) {
+			case 3:
+				modes = mode_4;
+				break;
+			case 1:
+				modes = mode_2;
+				break;
+			}
+			if (modes) {
+				if (!tmy_io_printf(head, "%u-%s=%s\n", index,
+						   keyword, modes[value]))
+					break;
+			} else {
+				if (!tmy_io_printf(head, "%u-%s=%u\n", index,
+						   keyword, value))
+					break;
+			}
+		}
+	}
+	if (step == MAX_PROFILES * total)
+		head->read_eof = true;
+	return 0;
+}
+
+/* Structure for policy manager. */
+struct policy_manager_entry {
+	struct list1_head list;
+	/* A path to program or a domainname. */
+	const struct path_info *manager;
+	bool is_domain;  /* True if manager is a domainname. */
+	bool is_deleted; /* True if this entry is deleted. */
+};
+
+/*
+ * The list for "struct policy_manager_entry".
+ *
+ * This list is updated only inside update_manager_entry(), thus
+ * no global mutex exists.
+ */
+static LIST1_HEAD(policy_manager_list);
+
+/**
+ * update_manager_entry - Add a manager entry.
+ *
+ * @manager:   The path to manager or the domainnamme.
+ * @is_delete: True if it is a delete request.
+ *
+ * Returns 0 on success, negative value otherwise.
+ */
+static int update_manager_entry(const char *manager, const bool is_delete)
+{
+	struct policy_manager_entry *new_entry;
+	struct policy_manager_entry *ptr;
+	static DEFINE_MUTEX(lock);
+	const struct path_info *saved_manager;
+	int error = -ENOMEM;
+	bool is_domain = false;
+
+	if (tmy_is_domain_def(manager)) {
+		if (!tmy_is_correct_domain(manager, __func__))
+			return -EINVAL;
+		is_domain = true;
+	} else {
+		if (!tmy_is_correct_path(manager, 1, -1, -1, __func__))
+			return -EINVAL;
+	}
+	saved_manager = tmy_save_name(manager);
+	if (!saved_manager)
+		return -ENOMEM;
+	/***** EXCLUSIVE SECTION START *****/
+	mutex_lock(&lock);
+	list1_for_each_entry(ptr, &policy_manager_list, list) {
+		if (ptr->manager != saved_manager)
+			continue;
+		ptr->is_deleted = is_delete;
+		error = 0;
+		goto out;
+	}
+	if (is_delete) {
+		error = -ENOENT;
+		goto out;
+	}
+	new_entry = tmy_alloc_element(sizeof(*new_entry));
+	if (!new_entry)
+		goto out;
+	new_entry->manager = saved_manager;
+	new_entry->is_domain = is_domain;
+	list1_add_tail(&new_entry->list, &policy_manager_list);
+	error = 0;
+out:
+	mutex_unlock(&lock);
+	/***** EXCLUSIVE SECTION END *****/
+	if (!error)
+		tmy_update_counter(TMY_UPDATES_COUNTER_MANAGER);
+	return error;
+}
+
+/**
+ * write_manager_policy - Write manager policy.
+ *
+ * @head: Pointer to "struct tmy_io_buffer"
+ *
+ * Returns 0 on success, negative value otherwise.
+ */
+static int write_manager_policy(struct tmy_io_buffer *head)
+{
+	char *data = head->write_buf;
+	bool is_delete = str_starts(&data, KEYWORD_DELETE);
+
+	if (!strcmp(data, "manage_by_non_root")) {
+		manage_by_non_root = !is_delete;
+		return 0;
+	}
+	return update_manager_entry(data, is_delete);
+}
+
+/**
+ * read_manager_policy - Read manager policy.
+ *
+ * @head: Pointer to "struct tmy_io_buffer"
+ *
+ * Returns 0.
+ */
+static int read_manager_policy(struct tmy_io_buffer *head)
+{
+	struct list1_head *pos;
+
+	if (head->read_eof)
+		return 0;
+	list1_for_each_cookie(pos, head->read_var2, &policy_manager_list) {
+		struct policy_manager_entry *ptr;
+		ptr = list1_entry(pos, struct policy_manager_entry, list);
+		if (ptr->is_deleted)
+			continue;
+		if (!tmy_io_printf(head, "%s\n", ptr->manager->name))
+			return 0;
+	}
+	head->read_eof = true;
+	return 0;
+}
+
+/**
+ * is_policy_manager - Check whether the current process is a policy manager.
+ *
+ * Returns true if the current process is permitted to modify policy
+ * via /sys/kernel/security/tomoyo/ interface.
+ */
+static bool is_policy_manager(void)
+{
+	struct policy_manager_entry *ptr;
+	const char *exe;
+	const struct task_struct *task = current;
+	const struct path_info *domainname = tmy_domain()->domainname;
+	bool found = false;
+
+	if (!sbin_init_started)
+		return true;
+	if (!manage_by_non_root && (task->cred->uid || task->cred->euid))
+		return false;
+	list1_for_each_entry(ptr, &policy_manager_list, list) {
+		if (!ptr->is_deleted && ptr->is_domain
+		    && !tmy_pathcmp(domainname, ptr->manager))
+			return true;
+	}
+	exe = tmy_get_exe();
+	if (!exe)
+		return false;
+	list1_for_each_entry(ptr, &policy_manager_list, list) {
+		if (!ptr->is_deleted && !ptr->is_domain
+		    && !strcmp(exe, ptr->manager->name)) {
+			found = true;
+			break;
+		}
+	}
+	if (!found) { /* Reduce error messages. */
+		static pid_t last_pid;
+		const pid_t pid = current->pid;
+		if (last_pid != pid) {
+			printk(KERN_WARNING "%s ( %s ) is not permitted to "
+			       "update policies.\n", domainname->name, exe);
+			last_pid = pid;
+		}
+	}
+	tmy_free(exe);
+	return found;
+}
+
+/**
+ * is_select_one - Parse select command.
+ *
+ * @head: Pointer to "struct tmy_io_buffer".
+ * @data: String to parse.
+ *
+ * Returns true on success, false otherwise.
+ */
+static bool is_select_one(struct tmy_io_buffer *head, const char *data)
+{
+	unsigned int pid;
+	struct domain_info *domain = NULL;
+
+	if (sscanf(data, "pid=%u", &pid) == 1) {
+		struct task_struct *p;
+		/***** CRITICAL SECTION START *****/
+		read_lock(&tasklist_lock);
+		p = find_task_by_vpid(pid);
+		if (p)
+			domain = tmy_real_domain(p);
+		read_unlock(&tasklist_lock);
+		/***** CRITICAL SECTION END *****/
+	} else if (!strncmp(data, "domain=", 7)) {
+		if (tmy_is_domain_def(data + 7))
+			domain = tmy_find_domain(data + 7);
+	} else
+		return false;
+	head->read_avail = 0;
+	tmy_io_printf(head, "# select %s\n", data);
+	head->read_single_domain = true;
+	head->read_eof = !domain;
+	if (domain) {
+		struct domain_info *d;
+		head->read_var1 = NULL;
+		list1_for_each_entry(d, &domain_list, list) {
+			if (d == domain)
+				break;
+			head->read_var1 = &d->list;
+		}
+		head->read_var2 = NULL;
+		head->read_bit = 0;
+		head->read_step = 0;
+		if (domain->is_deleted)
+			tmy_io_printf(head, "# This is a deleted domain.\n");
+	}
+	head->write_var1 = domain;
+	return true;
+}
+
+/**
+ * write_domain_policy - Write domain policy.
+ *
+ * @head: Pointer to "struct tmy_io_buffer".
+ *
+ * Returns 0 on success, negative value otherwise.
+ */
+static int write_domain_policy(struct tmy_io_buffer *head)
+{
+	char *data = head->write_buf;
+	struct domain_info *domain = head->write_var1;
+	bool is_delete = false;
+	bool is_select = false;
+	bool is_undelete = false;
+	unsigned int profile;
+
+	if (str_starts(&data, KEYWORD_DELETE))
+		is_delete = true;
+	else if (str_starts(&data, KEYWORD_SELECT))
+		is_select = true;
+	else if (str_starts(&data, KEYWORD_UNDELETE))
+		is_undelete = true;
+	if (is_select && is_select_one(head, data))
+		return 0;
+	/* Don't allow updating policies by non manager programs. */
+	if (!is_policy_manager())
+		return -EPERM;
+	if (tmy_is_domain_def(data)) {
+		domain = NULL;
+		if (is_delete)
+			tmy_delete_domain(data);
+		else if (is_select)
+			domain = tmy_find_domain(data);
+		else if (is_undelete)
+			domain = tmy_undelete_domain(data);
+		else
+			domain = tmy_find_or_assign_new_domain(data, 0);
+		head->write_var1 = domain;
+		tmy_update_counter(TMY_UPDATES_COUNTER_DOMAIN_POLICY);
+		return 0;
+	}
+	if (!domain)
+		return -EINVAL;
+
+	if (sscanf(data, KEYWORD_USE_PROFILE "%u", &profile) == 1
+	    && profile < MAX_PROFILES) {
+		if (profile_ptr[profile] || !sbin_init_started)
+			domain->profile = (u8) profile;
+		return 0;
+	}
+	if (!strcmp(data, KEYWORD_IGNORE_GLOBAL_ALLOW_READ)) {
+		tmy_set_domain_flag(domain, is_delete,
+				    DOMAIN_FLAGS_IGNORE_GLOBAL_ALLOW_READ);
+		return 0;
+	}
+	return tmy_write_file_policy(data, domain, is_delete);
+}
+
+/**
+ * print_single_path_acl - Print a single path ACL entry.
+ *
+ * @head: Pointer to "struct tmy_io_buffer".
+ * @ptr:  Pointer to "struct single_path_acl_record".
+ *
+ * Returns true on success, false otherwise.
+ */
+static bool print_single_path_acl(struct tmy_io_buffer *head,
+				  struct single_path_acl_record *ptr)
+{
+	int pos;
+	u8 bit;
+	const char *atmark = "";
+	const char *filename;
+	const u16 perm = ptr->perm;
+
+	filename = ptr->filename->name;
+	for (bit = head->read_bit; bit < MAX_SINGLE_PATH_OPERATION; bit++) {
+		const char *msg;
+		if (!(perm & (1 << bit)))
+			continue;
+		/* Print "read/write" instead of "read" and "write". */
+		if ((bit == TMY_TYPE_READ_ACL || bit == TMY_TYPE_WRITE_ACL)
+		    && (perm & (1 << TMY_TYPE_READ_WRITE_ACL)))
+			continue;
+		msg = tmy_sp2keyword(bit);
+		pos = head->read_avail;
+		if (!tmy_io_printf(head, "allow_%s %s%s\n", msg,
+				   atmark, filename))
+			goto out;
+	}
+	head->read_bit = 0;
+	return true;
+out:
+	head->read_bit = bit;
+	head->read_avail = pos;
+	return false;
+}
+
+/**
+ * print_double_path_acl - Print a double path ACL entry.
+ *
+ * @head: Pointer to "struct tmy_io_buffer".
+ * @ptr:  Pointer to "struct double_path_acl_record".
+ *
+ * Returns true on success, false otherwise.
+ */
+static bool print_double_path_acl(struct tmy_io_buffer *head,
+				  struct double_path_acl_record *ptr)
+{
+	int pos;
+	const char *atmark1 = "";
+	const char *atmark2 = "";
+	const char *filename1;
+	const char *filename2;
+	const u8 perm = ptr->perm;
+	u8 bit;
+
+	filename1 = ptr->filename1->name;
+	filename2 = ptr->filename2->name;
+	for (bit = head->read_bit; bit < MAX_DOUBLE_PATH_OPERATION; bit++) {
+		const char *msg;
+		if (!(perm & (1 << bit)))
+			continue;
+		msg = tmy_dp2keyword(bit);
+		pos = head->read_avail;
+		if (!tmy_io_printf(head, "allow_%s %s%s %s%s\n", msg,
+				   atmark1, filename1, atmark2, filename2))
+			goto out;
+	}
+	head->read_bit = 0;
+	return true;
+out:
+	head->read_bit = bit;
+	head->read_avail = pos;
+	return false;
+}
+
+/**
+ * print_entry - Print an ACL entry.
+ *
+ * @head: Pointer to "struct tmy_io_buffer".
+ * @ptr:  Pointer to an ACL entry.
+ *
+ * Returns true on success, false otherwise.
+ */
+static bool print_entry(struct tmy_io_buffer *head, struct acl_info *ptr)
+{
+	const u8 acl_type = tmy_acl_type2(ptr);
+
+	if (acl_type & ACL_DELETED)
+		return true;
+	if (acl_type == TYPE_SINGLE_PATH_ACL) {
+		struct single_path_acl_record *acl
+			= container_of(ptr, struct single_path_acl_record,
+				       head);
+		return print_single_path_acl(head, acl);
+	}
+	if (acl_type == TYPE_DOUBLE_PATH_ACL) {
+		struct double_path_acl_record *acl
+			= container_of(ptr, struct double_path_acl_record,
+				       head);
+		return print_double_path_acl(head, acl);
+	}
+	BUG(); /* This must not happen. */
+	return false;
+}
+
+/**
+ * read_domain_policy - Read domain policy.
+ *
+ * @head: Pointer to "struct tmy_io_buffer".
+ *
+ * Returns 0.
+ */
+static int read_domain_policy(struct tmy_io_buffer *head)
+{
+	struct list1_head *dpos;
+	struct list1_head *apos;
+
+	if (head->read_eof)
+		return 0;
+	if (head->read_step == 0)
+		head->read_step = 1;
+	list1_for_each_cookie(dpos, head->read_var1, &domain_list) {
+		struct domain_info *domain;
+		const char *quota_exceeded = "";
+		const char *transition_failed = "";
+		const char *ignore_global_allow_read = "";
+		domain = list1_entry(dpos, struct domain_info, list);
+		if (head->read_step != 1)
+			goto acl_loop;
+		if (domain->is_deleted && !head->read_single_domain)
+			continue;
+		/* Print domainname and flags. */
+		if (domain->quota_warned)
+			quota_exceeded = "quota_exceeded\n";
+		if (domain->flags & DOMAIN_FLAGS_TRANSITION_FAILED)
+			transition_failed = "transition_failed\n";
+		if (domain->flags & DOMAIN_FLAGS_IGNORE_GLOBAL_ALLOW_READ)
+			ignore_global_allow_read
+				= KEYWORD_IGNORE_GLOBAL_ALLOW_READ "\n";
+		if (!tmy_io_printf(head, "%s\n" KEYWORD_USE_PROFILE "%u\n"
+				   "%s%s%s\n", domain->domainname->name,
+				   domain->profile, quota_exceeded,
+				   transition_failed, ignore_global_allow_read))
+			return 0;
+		head->read_step = 2;
+acl_loop:
+		if (head->read_step == 3)
+			goto tail_mark;
+		/* Print ACL entries in the domain. */
+		list1_for_each_cookie(apos, head->read_var2,
+				      &domain->acl_info_list) {
+			struct acl_info *ptr
+				= list1_entry(apos, struct acl_info, list);
+			if (!print_entry(head, ptr))
+				return 0;
+		}
+		head->read_step = 3;
+tail_mark:
+		if (!tmy_io_printf(head, "\n"))
+			return 0;
+		head->read_step = 1;
+		if (head->read_single_domain)
+			break;
+	}
+	head->read_eof = true;
+	return 0;
+}
+
+/**
+ * write_domain_profile - Assign profile for specified domain.
+ *
+ * @head: Pointer to "struct tmy_io_buffer".
+ *
+ * Returns 0 on success, -EINVAL otherwise.
+ *
+ * This is equivalent to doing
+ *
+ *     ( echo "select " $domainname; echo "use_profile " $profile ) |
+ *     /usr/lib/ccs/loadpolicy -d
+ */
+static int write_domain_profile(struct tmy_io_buffer *head)
+{
+	char *data = head->write_buf;
+	char *cp = strchr(data, ' ');
+	struct domain_info *domain;
+	unsigned long profile;
+
+	if (!cp)
+		return -EINVAL;
+	*cp = '\0';
+	domain = tmy_find_domain(cp + 1);
+	strict_strtoul(data, 10, &profile);
+	if (domain && profile < MAX_PROFILES
+	    && (profile_ptr[profile] || !sbin_init_started))
+		domain->profile = (u8) profile;
+	tmy_update_counter(TMY_UPDATES_COUNTER_DOMAIN_POLICY);
+	return 0;
+}
+
+/**
+ * read_domain_profile - Read only domainname and profile.
+ *
+ * @head: Pointer to "struct tmy_io_buffer".
+ *
+ * Returns list of profile number and domainname pairs.
+ *
+ * This is equivalent to doing
+ *
+ *     grep -A 1 '^<kernel>' /sys/kernel/security/tomoyo/domain_policy |
+ *     awk ' { if ( domainname == "" ) { if ( $1 == "<kernel>" )
+ *     domainname = $0; } else if ( $1 == "use_profile" ) {
+ *     print $2 " " domainname; domainname = ""; } } ; '
+ */
+static int read_domain_profile(struct tmy_io_buffer *head)
+{
+	struct list1_head *pos;
+
+	if (head->read_eof)
+		return 0;
+	list1_for_each_cookie(pos, head->read_var1, &domain_list) {
+		struct domain_info *domain;
+		domain = list1_entry(pos, struct domain_info, list);
+		if (domain->is_deleted)
+			continue;
+		if (!tmy_io_printf(head, "%u %s\n", domain->profile,
+				   domain->domainname->name))
+			return 0;
+	}
+	head->read_eof = true;
+	return 0;
+}
+
+/**
+ * write_pid: Specify PID to obtain domainname.
+ *
+ * @head: Pointer to "struct tmy_io_buffer".
+ *
+ * Returns 0.
+ */
+static int write_pid(struct tmy_io_buffer *head)
+{
+	unsigned long pid;
+	strict_strtoul(head->write_buf, 10, &pid);
+	head->read_step = (int) pid;
+	head->read_eof = false;
+	return 0;
+}
+
+/**
+ * read_pid - Get domainname of the specified PID.
+ *
+ * @head: Pointer to "struct tmy_io_buffer".
+ *
+ * Returns the domainname which the specified PID is in on success,
+ * empty string otherwise.
+ * The PID is specified by write_pid() so that the user can obtain
+ * using read()/write() interface rather than sysctl() interface.
+ */
+static int read_pid(struct tmy_io_buffer *head)
+{
+	if (head->read_avail == 0 && !head->read_eof) {
+		const int pid = head->read_step;
+		struct task_struct *p;
+		struct domain_info *domain = NULL;
+		/***** CRITICAL SECTION START *****/
+		read_lock(&tasklist_lock);
+		p = find_task_by_vpid(pid);
+		if (p)
+			domain = tmy_real_domain(p);
+		read_unlock(&tasklist_lock);
+		/***** CRITICAL SECTION END *****/
+		if (domain)
+			tmy_io_printf(head, "%d %u %s", pid, domain->profile,
+				      domain->domainname->name);
+		head->read_eof = true;
+	}
+	return 0;
+}
+
+/**
+ * write_exception_policy - Write exception policy.
+ *
+ * @head: Pointer to "struct tmy_io_buffer".
+ *
+ * Returns 0 on success, negative value otherwise.
+ */
+static int write_exception_policy(struct tmy_io_buffer *head)
+{
+	char *data = head->write_buf;
+	bool is_delete = str_starts(&data, KEYWORD_DELETE);
+
+	if (str_starts(&data, KEYWORD_KEEP_DOMAIN))
+		return tmy_write_domain_keeper_policy(data, false, is_delete);
+	if (str_starts(&data, KEYWORD_NO_KEEP_DOMAIN))
+		return tmy_write_domain_keeper_policy(data, true, is_delete);
+	if (str_starts(&data, KEYWORD_INITIALIZE_DOMAIN))
+		return tmy_write_domain_initializer_policy(data, false,
+							   is_delete);
+	if (str_starts(&data, KEYWORD_NO_INITIALIZE_DOMAIN))
+		return tmy_write_domain_initializer_policy(data, true,
+							   is_delete);
+	if (str_starts(&data, KEYWORD_ALIAS))
+		return tmy_write_alias_policy(data, is_delete);
+	if (str_starts(&data, KEYWORD_ALLOW_READ))
+		return tmy_write_globally_readable_policy(data, is_delete);
+	if (str_starts(&data, KEYWORD_FILE_PATTERN))
+		return tmy_write_pattern_policy(data, is_delete);
+	if (str_starts(&data, KEYWORD_DENY_REWRITE))
+		return tmy_write_no_rewrite_policy(data, is_delete);
+	return -EINVAL;
+}
+
+/**
+ * read_exception_policy - Read exception policy.
+ *
+ * @head: Pointer to "struct tmy_io_buffer".
+ *
+ * Returns 0 on success, -EINVAL otherwise.
+ */
+static int read_exception_policy(struct tmy_io_buffer *head)
+{
+	if (!head->read_eof) {
+		switch (head->read_step) {
+		case 0:
+			head->read_var2 = NULL;
+			head->read_step = 1;
+		case 1:
+			if (!tmy_read_domain_keeper_policy(head))
+				break;
+			head->read_var2 = NULL;
+			head->read_step = 2;
+		case 2:
+			if (!tmy_read_globally_readable_policy(head))
+				break;
+			head->read_var2 = NULL;
+			head->read_step = 3;
+		case 3:
+			head->read_var2 = NULL;
+			head->read_step = 4;
+		case 4:
+			if (!tmy_read_domain_initializer_policy(head))
+				break;
+			head->read_var2 = NULL;
+			head->read_step = 5;
+		case 5:
+			if (!tmy_read_alias_policy(head))
+				break;
+			head->read_var2 = NULL;
+			head->read_step = 6;
+		case 6:
+			head->read_var2 = NULL;
+			head->read_step = 7;
+		case 7:
+			if (!tmy_read_file_pattern(head))
+				break;
+			head->read_var2 = NULL;
+			head->read_step = 8;
+		case 8:
+			if (!tmy_read_no_rewrite_policy(head))
+				break;
+			head->read_var2 = NULL;
+			head->read_step = 9;
+		case 9:
+			head->read_eof = true;
+			break;
+		default:
+			return -EINVAL;
+		}
+	}
+	return 0;
+}
+
+/* path to policy loader */
+static const char *tmy_loader = "/sbin/tomoyo-init";
+
+/**
+ * policy_loader_exists - Check whether /sbin/tomoyo-init exists.
+ *
+ * Returns true if /sbin/tomoyo-init exists, false otherwise.
+ */
+static bool policy_loader_exists(void)
+{
+	/*
+	 * Don't activate MAC if the policy loader doesn't exist.
+	 * If the initrd includes /sbin/init but real-root-dev has not
+	 * mounted on / yet, activating MAC will block the system since
+	 * policies are not loaded yet.
+	 * Thus, let do_execve() call this function everytime.
+	 */
+	struct nameidata nd;
+
+	if (path_lookup(tmy_loader, LOOKUP_FOLLOW, &nd)) {
+		printk(KERN_INFO "Not activating Mandatory Access Control now "
+		       "since %s doesn't exist.\n", tmy_loader);
+		return false;
+	}
+	path_put(&nd.path);
+	return true;
+}
+
+/**
+ * tmy_load_policy - Run external policy loader to load policy.
+ *
+ * @filename: The program about to start.
+ *
+ * This function checks whether @filename is /sbin/init , and if so
+ * invoke /sbin/tomoyo-init and wait for the termination of /sbin/tomoyo-init
+ * and then continues invocation of /sbin/init.
+ * /sbin/tomoyo-init reads policy files in /etc/tomoyo/ directory and
+ * writes to /sys/kernel/security/tomoyo/ interfaces.
+ *
+ * Returns nothing.
+ */
+void tmy_load_policy(const char *filename)
+{
+	char *argv[2];
+	char *envp[3];
+
+	if (sbin_init_started)
+		return;
+	/*
+	 * Check filename is /sbin/init or /sbin/tomoyo-start.
+	 * /sbin/tomoyo-start is a dummy filename in case where /sbin/init can't
+	 * be passed.
+	 * You can create /sbin/tomoyo-start by
+	 * "ln -s /bin/true /sbin/tomoyo-start".
+	 */
+	if (strcmp(filename, "/sbin/init") &&
+	    strcmp(filename, "/sbin/tomoyo-start"))
+		return;
+	if (!policy_loader_exists())
+		return;
+
+	printk(KERN_INFO "Calling %s to load policy. Please wait.\n",
+	       tmy_loader);
+	argv[0] = (char *) tmy_loader;
+	argv[1] = NULL;
+	envp[0] = "HOME=/";
+	envp[1] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
+	envp[2] = NULL;
+	call_usermodehelper(argv[0], argv, envp, 1);
+
+	printk(KERN_INFO "TOMOYO: 2.2.0-pre   2008/10/10\n");
+	printk(KERN_INFO "Mandatory Access Control activated.\n");
+	sbin_init_started = true;
+	{ /* Check all profiles currently assigned to domains are defined. */
+		struct domain_info *domain;
+		list1_for_each_entry(domain, &domain_list, list) {
+			const u8 profile = domain->profile;
+			if (profile_ptr[profile])
+				continue;
+			panic("Profile %u (used by '%s') not defined.\n",
+			      profile, domain->domainname->name);
+		}
+	}
+}
+
+/* Policy updates counter. */
+static atomic_t updates_counter[MAX_TMY_UPDATES_COUNTER];
+
+/**
+ * tmy_update_counter - Increment policy change counter.
+ *
+ * @index: Type of policy.
+ *
+ * Returns nothing.
+ */
+void tmy_update_counter(const unsigned char index)
+{
+	if (index < MAX_TMY_UPDATES_COUNTER)
+		atomic_inc(&updates_counter[index]);
+}
+
+/**
+ * read_updates_counter - Check for policy change counter.
+ *
+ * @head: Pointer to "struct tmy_io_buffer".
+ *
+ * Returns how many times policy has changed since the previous check.
+ */
+static int read_updates_counter(struct tmy_io_buffer *head)
+{
+	if (head->read_eof)
+		return 0;
+	tmy_io_printf(head,
+		      "/sys/kernel/security/tomoyo/domain_policy:    %10u\n"
+		      "/sys/kernel/security/tomoyo/exception_policy: %10u\n"
+		      "/sys/kernel/security/tomoyo/profile:          %10u\n"
+		      "/sys/kernel/security/tomoyo/manager:          %10u\n",
+		      atomic_xchg(&updates_counter
+				  [TMY_UPDATES_COUNTER_DOMAIN_POLICY], 0),
+		      atomic_xchg(&updates_counter
+				  [TMY_UPDATES_COUNTER_EXCEPTION_POLICY], 0),
+		      atomic_xchg(&updates_counter
+				  [TMY_UPDATES_COUNTER_PROFILE], 0),
+		      atomic_xchg(&updates_counter
+				  [TMY_UPDATES_COUNTER_MANAGER], 0));
+	head->read_eof = true;
+	return 0;
+}
+
+/**
+ * read_version: Get version.
+ *
+ * @head: Pointer to "struct tmy_io_buffer".
+ *
+ * Returns version information.
+ */
+static int read_version(struct tmy_io_buffer *head)
+{
+	if (!head->read_eof) {
+		tmy_io_printf(head, "2.2.0-pre");
+		head->read_eof = true;
+	}
+	return 0;
+}
+
+/**
+ * read_self_domain - Get the current process's domainname.
+ *
+ * @head: Pointer to "struct tmy_io_buffer".
+ *
+ * Returns the current process's domainname.
+ */
+static int read_self_domain(struct tmy_io_buffer *head)
+{
+	if (!head->read_eof) {
+		/*
+		 * tmy_domain()->domainname != NULL
+		 * because every process belongs to a domain and
+		 * the domain's name cannot be NULL.
+		 */
+		tmy_io_printf(head, "%s", tmy_domain()->domainname->name);
+		head->read_eof = true;
+	}
+	return 0;
+}
+
+/**
+ * tmy_open_control - open() for /sys/kernel/security/tomoyo/ interface.
+ *
+ * @type: Type of interface.
+ * @file: Pointer to "struct file".
+ *
+ * Associates policy handler and returns 0 on success, -ENOMEM otherwise.
+ */
+static int tmy_open_control(const u8 type, struct file *file)
+{
+	struct tmy_io_buffer *head = tmy_alloc(sizeof(*head));
+
+	if (!head)
+		return -ENOMEM;
+	mutex_init(&head->io_sem);
+	switch (type) {
+	case TMY_DOMAINPOLICY:
+		/* /sys/kernel/security/tomoyo/domain_policy */
+		head->write = write_domain_policy;
+		head->read = read_domain_policy;
+		break;
+	case TMY_EXCEPTIONPOLICY:
+		/* /sys/kernel/security/tomoyo/exception_policy */
+		head->write = write_exception_policy;
+		head->read = read_exception_policy;
+		break;
+	case TMY_SELFDOMAIN:
+		/* /sys/kernel/security/tomoyo/self_domain */
+		head->read = read_self_domain;
+		break;
+	case TMY_DOMAIN_STATUS:
+		/* /sys/kernel/security/tomoyo/.domain_status */
+		head->write = write_domain_profile;
+		head->read = read_domain_profile;
+		break;
+	case TMY_PROCESS_STATUS:
+		/* /sys/kernel/security/tomoyo/.process_status */
+		head->write = write_pid;
+		head->read = read_pid;
+		break;
+	case TMY_VERSION:
+		/* /sys/kernel/security/tomoyo/version */
+		head->read = read_version;
+		head->readbuf_size = 128;
+		break;
+	case TMY_MEMINFO:
+		/* /sys/kernel/security/tomoyo/meminfo */
+		head->write = tmy_write_memory_quota;
+		head->read = tmy_read_memory_counter;
+		head->readbuf_size = 512;
+		break;
+	case TMY_PROFILE:
+		/* /sys/kernel/security/tomoyo/profile */
+		head->write = write_profile;
+		head->read = read_profile;
+		break;
+	case TMY_MANAGER:
+		/* /sys/kernel/security/tomoyo/manager */
+		head->write = write_manager_policy;
+		head->read = read_manager_policy;
+		break;
+	case TMY_UPDATESCOUNTER:
+		/* /sys/kernel/security/tomoyo/.updates_counter */
+		head->read = read_updates_counter;
+		break;
+	}
+	if (!(file->f_mode & FMODE_READ)) {
+		/*
+		 * No need to allocate read_buf since it is not opened
+		 * for reading.
+		 */
+		head->read = NULL;
+	} else {
+		if (!head->readbuf_size)
+			head->readbuf_size = 4096 * 2;
+		head->read_buf = tmy_alloc(head->readbuf_size);
+		if (!head->read_buf) {
+			tmy_free(head);
+			return -ENOMEM;
+		}
+	}
+	if (!(file->f_mode & FMODE_WRITE)) {
+		/*
+		 * No need to allocate write_buf since it is not opened
+		 * for writing.
+		 */
+		head->write = NULL;
+	} else if (head->write) {
+		head->writebuf_size = 4096 * 2;
+		head->write_buf = tmy_alloc(head->writebuf_size);
+		if (!head->write_buf) {
+			tmy_free(head->read_buf);
+			tmy_free(head);
+			return -ENOMEM;
+		}
+	}
+	file->private_data = head;
+	/*
+	 * Call the handler now if the file is
+	 * /sys/kernel/security/tomoyo/self_domain
+	 * so that the user can use
+	 * cat < /sys/kernel/security/tomoyo/self_domain"
+	 * to know the current process's domainname.
+	 */
+	if (type == TMY_SELFDOMAIN)
+		tmy_read_control(file, NULL, 0);
+	return 0;
+}
+
+/**
+ * tmy_read_control - read() for /sys/kernel/security/tomoyo/ interface.
+ *
+ * @file:       Pointer to "struct file".
+ * @buffer:     Poiner to buffer to write to.
+ * @buffer_len: Size of @buffer.
+ *
+ * Returns bytes read on success, negative value otherwise.
+ */
+static int tmy_read_control(struct file *file, char __user *buffer,
+			    const int buffer_len)
+{
+	int len = 0;
+	struct tmy_io_buffer *head = file->private_data;
+	char *cp;
+
+	if (!head->read)
+		return -ENOSYS;
+	if (!access_ok(VERIFY_WRITE, buffer, buffer_len))
+		return -EFAULT;
+	if (mutex_lock_interruptible(&head->io_sem))
+		return -EINTR;
+	/* Call the policy handler. */
+	len = head->read(head);
+	if (len < 0)
+		goto out;
+	/* Write to buffer. */
+	len = head->read_avail;
+	if (len > buffer_len)
+		len = buffer_len;
+	if (!len)
+		goto out;
+	/* head->read_buf changes by some functions. */
+	cp = head->read_buf;
+	if (copy_to_user(buffer, cp, len)) {
+		len = -EFAULT;
+		goto out;
+	}
+	head->read_avail -= len;
+	memmove(cp, cp + len, head->read_avail);
+out:
+	mutex_unlock(&head->io_sem);
+	return len;
+}
+
+/**
+ * tmy_write_control - write() for /sys/kernel/security/tomoyo/ interface.
+ *
+ * @file:       Pointer to "struct file".
+ * @buffer:     Pointer to buffer to read from.
+ * @buffer_len: Size of @buffer.
+ *
+ * Returns @buffer_len on success, negative value otherwise.
+ */
+static int tmy_write_control(struct file *file, const char __user *buffer,
+			     const int buffer_len)
+{
+	struct tmy_io_buffer *head = file->private_data;
+	int error = buffer_len;
+	int avail_len = buffer_len;
+	char *cp0 = head->write_buf;
+
+	if (!head->write)
+		return -ENOSYS;
+	if (!access_ok(VERIFY_READ, buffer, buffer_len))
+		return -EFAULT;
+	/* Don't allow updating policies by non manager programs. */
+	if (head->write != write_pid && head->write != write_domain_policy &&
+	    !is_policy_manager())
+		return -EPERM;
+	if (mutex_lock_interruptible(&head->io_sem))
+		return -EINTR;
+	/* Read a line and dispatch it to the policy handler. */
+	while (avail_len > 0) {
+		char c;
+		if (head->write_avail >= head->writebuf_size - 1) {
+			error = -ENOMEM;
+			break;
+		} else if (get_user(c, buffer)) {
+			error = -EFAULT;
+			break;
+		}
+		buffer++;
+		avail_len--;
+		cp0[head->write_avail++] = c;
+		if (c != '\n')
+			continue;
+		cp0[head->write_avail - 1] = '\0';
+		head->write_avail = 0;
+		normalize_line(cp0);
+		head->write(head);
+	}
+	mutex_unlock(&head->io_sem);
+	return error;
+}
+
+/**
+ * tmy_close_control - close() for /sys/kernel/security/tomoyo/ interface.
+ *
+ * @file: Pointer to "struct file".
+ *
+ * Releases memory and returns 0.
+ */
+static int tmy_close_control(struct file *file)
+{
+	struct tmy_io_buffer *head = file->private_data;
+
+	/* Release memory used for policy I/O. */
+	tmy_free(head->read_buf);
+	head->read_buf = NULL;
+	tmy_free(head->write_buf);
+	head->write_buf = NULL;
+	tmy_free(head);
+	head = NULL;
+	file->private_data = NULL;
+	return 0;
+}
+
+/**
+ * tmy_alloc_acl_element - Allocate permanent memory for ACL entry.
+ *
+ * @acl_type:  Type of ACL entry.
+ *
+ * Returns pointer to the ACL entry on success, NULL otherwise.
+ */
+void *tmy_alloc_acl_element(const u8 acl_type)
+{
+	int len;
+	struct acl_info *ptr;
+
+	switch (acl_type) {
+	case TYPE_SINGLE_PATH_ACL:
+		len = sizeof(struct single_path_acl_record);
+		break;
+	case TYPE_DOUBLE_PATH_ACL:
+		len = sizeof(struct double_path_acl_record);
+		break;
+	default:
+		return NULL;
+	}
+	ptr = tmy_alloc_element(len);
+	if (!ptr)
+		return NULL;
+	ptr->type = acl_type;
+	return ptr;
+}
+
+/**
+ * tmy_open - open() for /sys/kernel/security/tomoyo/ interface.
+ *
+ * @inode: Pointer to "struct inode".
+ * @file:  Pointer to "struct file".
+ *
+ * Returns 0 on success, negative value otherwise.
+ */
+static int tmy_open(struct inode *inode, struct file *file)
+{
+	return tmy_open_control(((u8 *) file->f_path.dentry->d_inode->i_private)
+				- ((u8 *) NULL), file);
+}
+
+/**
+ * tmy_release - close() for /sys/kernel/security/tomoyo/ interface.
+ *
+ * @inode: Pointer to "struct inode".
+ * @file:  Pointer to "struct file".
+ *
+ * Returns 0 on success, negative value otherwise.
+ */
+static int tmy_release(struct inode *inode, struct file *file)
+{
+	return tmy_close_control(file);
+}
+
+/**
+ * tmy_read - read() for /sys/kernel/security/tomoyo/ interface.
+ *
+ * @file:  Pointer to "struct file".
+ * @buf:   Pointer to buffer.
+ * @count: Size of @buf.
+ * @ppos:  Unused.
+ *
+ * Returns bytes read on success, negative value otherwise.
+ */
+static ssize_t tmy_read(struct file *file, char __user *buf, size_t count,
+			loff_t *ppos)
+{
+	return tmy_read_control(file, buf, count);
+}
+
+/**
+ * tmy_write - write() for /sys/kernel/security/tomoyo/ interface.
+ *
+ * @file:  Pointer to "struct file".
+ * @buf:   Pointer to buffer.
+ * @count: Size of @buf.
+ * @ppos:  Unused.
+ *
+ * Returns @count on success, negative value otherwise.
+ */
+static ssize_t tmy_write(struct file *file, const char __user *buf,
+			 size_t count, loff_t *ppos)
+{
+	return tmy_write_control(file, buf, count);
+}
+
+/* Operations for /sys/kernel/security/tomoyo/ interface. */
+static struct file_operations tmy_operations = {
+	.open    = tmy_open,
+	.release = tmy_release,
+	.read    = tmy_read,
+	.write   = tmy_write,
+};
+
+/**
+ * create_entry - Create interface files under /sys/kernel/security/tomoyo/ directory.
+ *
+ * @name:   The name of the interface file.
+ * @mode:   The permission of the interface file.
+ * @parent: The parent directory.
+ * @key:    Type of interface.
+ *
+ * Returns nothing.
+ */
+static void __init create_entry(const char *name, const mode_t mode,
+				struct dentry *parent, const u8 key)
+{
+	securityfs_create_file(name, mode, parent, ((u8 *) NULL) + key,
+			       &tmy_operations);
+}
+
+/**
+ * tmy_initerface_init - Initialize /sys/kernel/security/tomoyo/ interface.
+ *
+ * Returns 0.
+ */
+static int __init tmy_initerface_init(void)
+{
+	struct dentry *tmy_dir;
+
+	tmy_dir = securityfs_create_dir("tomoyo", NULL);
+	create_entry("domain_policy",    0600, tmy_dir, TMY_DOMAINPOLICY);
+	create_entry("exception_policy", 0600, tmy_dir, TMY_EXCEPTIONPOLICY);
+	create_entry("self_domain",      0400, tmy_dir, TMY_SELFDOMAIN);
+	create_entry(".domain_status",   0600, tmy_dir, TMY_DOMAIN_STATUS);
+	create_entry(".process_status",  0600, tmy_dir, TMY_PROCESS_STATUS);
+	create_entry("meminfo",          0600, tmy_dir, TMY_MEMINFO);
+	create_entry("profile",          0600, tmy_dir, TMY_PROFILE);
+	create_entry("manager",          0600, tmy_dir, TMY_MANAGER);
+	create_entry(".updates_counter", 0400, tmy_dir, TMY_UPDATESCOUNTER);
+	create_entry("version",          0400, tmy_dir, TMY_VERSION);
+	return 0;
+}
+
+fs_initcall(tmy_initerface_init);