/*
* Return a path relative to our root.
*/
char * umsdos_d_path(struct dentry *dentry, char * buffer, int len)
{
struct dentry * old_root;
char * path;
read_lock(¤t->fs->lock);
old_root = dget(current->fs->root);
read_unlock(¤t->fs->lock);
spin_lock(&dcache_lock);
path = __d_path(dentry, current->fs->rootmnt, dentry->d_sb->s_root, current->fs->rootmnt, buffer, len); /* FIXME: current->fs->rootmnt */
spin_unlock(&dcache_lock);
if (IS_ERR(path))
return path;
if (*path == '/')
path++; /* skip leading '/' */
if (current->fs->root->d_inode == pseudo_root)
{
*(path-1) = '/';
path -= (UMSDOS_PSDROOT_LEN+1);
memcpy(path, UMSDOS_PSDROOT_NAME, UMSDOS_PSDROOT_LEN);
}
dput(old_root);
return path;
}
static int _xx_realpath_from_path(struct path *path, char *newname,
int newname_len)
{
struct dentry *dentry = path->dentry;
int error = -ENOMEM;
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 {
/* Taken from d_namespace_path(). */
struct path ns_root = { };
struct path root;
struct path tmp;
read_lock(¤t->fs->lock);
root = current->fs->root;
path_get(&root);
read_unlock(¤t->fs->lock);
spin_lock(&vfsmount_lock);
if (root.mnt && root.mnt->mnt_ns)
ns_root.mnt = mntget(root.mnt->mnt_ns->root);
if (ns_root.mnt)
ns_root.dentry = dget(ns_root.mnt->mnt_root);
spin_unlock(&vfsmount_lock);
spin_lock(&dcache_lock);
tmp = ns_root;
sp = __d_path(path, &tmp, newname, newname_len);
spin_unlock(&dcache_lock);
path_put(&root);
path_put(&ns_root);
}
if (IS_ERR(sp)) {
error = PTR_ERR(sp);
} else {
error = _xx_encode(newname, sp - newname, sp);
}
#if 1
/* Append trailing '/' if dentry is a directory. */
if (!error && dentry->d_inode && S_ISDIR(dentry->d_inode->i_mode)
&& *newname) {
sp = newname + strlen(newname);
if (*(sp - 1) != '/') {
if (sp < newname + newname_len - 4) {
*sp++ = '/';
*sp = '\0';
} else {
error = -ENOMEM;
}
}
}
#endif
return error;
}
int _xx_realpath_from_path(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 {
struct path ns_root = {.mnt = NULL, .dentry = NULL};
spin_lock(&dcache_lock);
/* go to whatever namespace root we are under */
sp = __d_path(path, &ns_root, newname, newname_len);
spin_unlock(&dcache_lock);
/* Prepend "/proc" prefix if using internal proc vfs mount. */
if (!IS_ERR(sp) && (path->mnt->mnt_flags & MNT_INTERNAL) &&
(path->mnt->mnt_sb->s_magic == PROC_SUPER_MAGIC)) {
sp -= 5;
if (sp >= newname)
memcpy(sp, "/proc", 5);
else
sp = ERR_PTR(-ENOMEM);
}
}
if (IS_ERR(sp))
error = PTR_ERR(sp);
else
error = _xx_encode(newname, sp - newname, sp);
/* Append trailing '/' if dentry is a directory. */
if (!error && dentry->d_inode && S_ISDIR(dentry->d_inode->i_mode)
&& *newname) {
sp = newname + strlen(newname);
if (*(sp - 1) != '/') {
if (sp < newname + newname_len - 4) {
*sp++ = '/';
*sp = '\0';
} else {
error = -ENOMEM;
}
}
}
return error;
}
/**
* tomoyo_get_absolute_path - Get the path of a dentry but ignores chroot'ed root.
*
* @path: Pointer to "struct path".
* @buffer: Pointer to buffer to return value in.
* @buflen: Sizeof @buffer.
*
* Returns the buffer on success, an error code otherwise.
*
* If dentry is a directory, trailing '/' is appended.
*/
static char *tomoyo_get_absolute_path(struct path *path, char * const buffer,
const int buflen)
{
char *pos = ERR_PTR(-ENOMEM);
if (buflen >= 256) {
struct path ns_root = { };
/* go to whatever namespace root we are under */
pos = __d_path(path, &ns_root, buffer, buflen - 1);
if (!IS_ERR(pos) && *pos == '/' && pos[1]) {
struct inode *inode = path->dentry->d_inode;
if (inode && S_ISDIR(inode->i_mode)) {
buffer[buflen - 2] = '/';
buffer[buflen - 1] = '\0';
}
}
}
return pos;
}
char * tux_print_path (tux_req_t *req, struct dentry *dentry, struct vfsmount *mnt, char *buf, unsigned int max_len)
{
char *res;
struct dentry *cwd, *root;
struct vfsmount *cwd_mnt, *rootmnt;
cwd = dget(dentry);
cwd_mnt = mntget(mnt);
root = dget(req->docroot_dentry);
rootmnt = mntget(req->docroot_mnt);
spin_lock(&dcache_lock);
res = __d_path(cwd, cwd_mnt, root, rootmnt, buf, max_len);
spin_unlock(&dcache_lock);
dput(cwd);
mntput(cwd_mnt);
dput(root);
mntput(rootmnt);
return res;
}
/**
* d_namespace_path - lookup a name associated with a given path
* @path: path to lookup (NOT NULL)
* @buf: buffer to store path to (NOT NULL)
* @buflen: length of @buf
* @name: Returns - pointer for start of path name with in @buf (NOT NULL)
* @flags: flags controlling path lookup
*
* Handle path name lookup.
*
* Returns: %0 else error code if path lookup fails
* When no error the path name is returned in @name which points to
* to a position in @buf
*/
static int d_namespace_path(struct path *path, char *buf, int buflen,
char **name, int flags)
{
struct path root, tmp;
char *res;
int connected, error = 0;
/* Get the root we want to resolve too, released below */
if (flags & PATH_CHROOT_REL) {
/* resolve paths relative to chroot */
get_fs_root(current->fs, &root);
} else {
/* resolve paths relative to namespace */
root.mnt = current->nsproxy->mnt_ns->root;
root.dentry = root.mnt->mnt_root;
path_get(&root);
}
tmp = root;
res = __d_path(path, &tmp, buf, buflen);
*name = res;
/* handle error conditions - and still allow a partial path to
* be returned.
*/
if (IS_ERR(res)) {
error = PTR_ERR(res);
*name = buf;
goto out;
}
/* Handle two cases:
* 1. A deleted dentry && profile is not allowing mediation of deleted
* 2. On some filesystems, newly allocated dentries appear to the
* security_path hooks as a deleted dentry except without an inode
* allocated.
*/
if (d_unlinked(path->dentry) && path->dentry->d_inode &&
!(flags & PATH_MEDIATE_DELETED)) {
error = -ENOENT;
goto out;
}
/* Determine if the path is connected to the expected root */
connected = tmp.dentry == root.dentry && tmp.mnt == root.mnt;
/* If the path is not connected,
* check if it is a sysctl and handle specially else remove any
* leading / that __d_path may have returned.
* Unless
* specifically directed to connect the path,
* OR
* if in a chroot and doing chroot relative paths and the path
* resolves to the namespace root (would be connected outside
* of chroot) and specifically directed to connect paths to
* namespace root.
*/
if (!connected) {
/* is the disconnect path a sysctl? */
if (tmp.dentry->d_sb->s_magic == PROC_SUPER_MAGIC &&
strncmp(*name, "/sys/", 5) == 0) {
/* TODO: convert over to using a per namespace
* control instead of hard coded /proc
*/
error = prepend(name, *name - buf, "/proc", 5);
} else if (!(flags & PATH_CONNECT_PATH) &&
!(((flags & CHROOT_NSCONNECT) == CHROOT_NSCONNECT) &&
(tmp.mnt == current->nsproxy->mnt_ns->root &&
tmp.dentry == tmp.mnt->mnt_root))) {
/* disconnected path, don't return pathname starting
* with '/'
*/
error = -ESTALE;
if (*res == '/')
*name = res + 1;
}
}
out:
path_put(&root);
return error;
}
/**
* d_namespace_path - lookup a name associated with a given path
* @path: path to lookup (NOT NULL)
* @buf: buffer to store path to (NOT NULL)
* @buflen: length of @buf
* @name: Returns - pointer for start of path name with in @buf (NOT NULL)
* @flags: flags controlling path lookup
*
* Handle path name lookup.
*
* Returns: %0 else error code if path lookup fails
* When no error the path name is returned in @name which points to
* to a position in @buf
*/
static int d_namespace_path(struct path *path, char *buf, int buflen,
char **name, int flags)
{
char *res;
int error = 0;
int connected = 1;
if (path->mnt->mnt_flags & MNT_INTERNAL) {
/* it's not mounted anywhere */
res = dentry_path(path->dentry, buf, buflen);
*name = res;
if (IS_ERR(res)) {
*name = buf;
return PTR_ERR(res);
}
if (path->dentry->d_sb->s_magic == PROC_SUPER_MAGIC &&
strncmp(*name, "/sys/", 5) == 0) {
/* TODO: convert over to using a per namespace
* control instead of hard coded /proc
*/
return prepend(name, *name - buf, "/proc", 5);
}
return 0;
}
/* resolve paths relative to chroot?*/
if (flags & PATH_CHROOT_REL) {
struct path root;
get_fs_root(current->fs, &root);
res = __d_path(path, &root, buf, buflen);
path_put(&root);
} else {
res = d_absolute_path(path, buf, buflen);
if (!our_mnt(path->mnt))
connected = 0;
}
/* handle error conditions - and still allow a partial path to
* be returned.
*/
if (!res || IS_ERR(res)) {
connected = 0;
res = dentry_path_raw(path->dentry, buf, buflen);
if (IS_ERR(res)) {
error = PTR_ERR(res);
*name = buf;
goto out;
};
} else if (!our_mnt(path->mnt))
connected = 0;
*name = res;
/* Handle two cases:
* 1. A deleted dentry && profile is not allowing mediation of deleted
* 2. On some filesystems, newly allocated dentries appear to the
* security_path hooks as a deleted dentry except without an inode
* allocated.
*/
if (d_unlinked(path->dentry) && path->dentry->d_inode &&
!(flags & PATH_MEDIATE_DELETED)) {
error = -ENOENT;
goto out;
}
/* If the path is not connected to the expected root,
* check if it is a sysctl and handle specially else remove any
* leading / that __d_path may have returned.
* Unless
* specifically directed to connect the path,
* OR
* if in a chroot and doing chroot relative paths and the path
* resolves to the namespace root (would be connected outside
* of chroot) and specifically directed to connect paths to
* namespace root.
*/
if (!connected) {
if (!(flags & PATH_CONNECT_PATH) &&
!(((flags & CHROOT_NSCONNECT) == CHROOT_NSCONNECT) &&
our_mnt(path->mnt))) {
/* disconnected path, don't return pathname starting
* with '/'
*/
error = -ESTALE;
if (*res == '/')
*name = res + 1;
}
}
out:
return error;
}
/**
* tomoyo_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 tomoyo_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 {
/* Taken from d_namespace_path(). */
struct path root;
struct path ns_root = { };
struct path tmp;
read_lock(¤t->fs->lock);
root = current->fs->root;
path_get(&root);
read_unlock(¤t->fs->lock);
spin_lock(&vfsmount_lock);
if (root.mnt && root.mnt->mnt_ns)
ns_root.mnt = mntget(root.mnt->mnt_ns->root);
if (ns_root.mnt)
ns_root.dentry = dget(ns_root.mnt->mnt_root);
spin_unlock(&vfsmount_lock);
spin_lock(&dcache_lock);
tmp = ns_root;
sp = __d_path(path, &tmp, newname, newname_len);
spin_unlock(&dcache_lock);
path_put(&root);
path_put(&ns_root);
/* Prepend "/proc" prefix if using internal proc vfs mount. */
if (!IS_ERR(sp) && (path->mnt->mnt_parent == path->mnt) &&
(strcmp(path->mnt->mnt_sb->s_type->name, "proc") == 0)) {
sp -= 5;
if (sp >= newname)
memcpy(sp, "/proc", 5);
else
sp = ERR_PTR(-ENOMEM);
}
}
if (IS_ERR(sp))
error = PTR_ERR(sp);
else
error = tomoyo_encode(newname, sp - newname, sp);
/* Append trailing '/' if dentry is a directory. */
if (!error && dentry->d_inode && S_ISDIR(dentry->d_inode->i_mode)
&& *newname) {
sp = newname + strlen(newname);
if (*(sp - 1) != '/') {
if (sp < newname + newname_len - 4) {
*sp++ = '/';
*sp = '\0';
} else {
error = -ENOMEM;
}
}
}
if (error)
printk(KERN_WARNING "tomoyo_realpath: Pathname too long.\n");
return error;
}
/**
* d_namespace_path - lookup a name associated with a given path
* @path: path to lookup (NOT NULL)
* @buf: buffer to store path to (NOT NULL)
* @buflen: length of @buf
* @name: return pointer for start of path name with in @buf (NOT NULL)
* @flags: flags controling path lookup
*
* Handle path name lookup.
*
* Returns: %0 else error code if path lookup fails
* When no error the path name is returned in @name which points to
* to a position in @buf
*/
static int d_namespace_path(struct path *path, char *buf, int buflen,
char **name, int flags)
{
struct path root, tmp;
char *res;
int deleted, connected;
int error = 0;
/* Get the root we want to resolve too */
if (flags & PATH_CHROOT_REL) {
/* resolve paths relative to chroot */
read_lock(¤t->fs->lock);
root = current->fs->root;
/* released below */
path_get(&root);
read_unlock(¤t->fs->lock);
} else {
/* resolve paths relative to namespace */
root.mnt = current->nsproxy->mnt_ns->root;
root.dentry = root.mnt->mnt_root;
/* released below */
path_get(&root);
}
spin_lock(&dcache_lock);
/* There is a race window between path lookup here and the
* need to strip the " (deleted) string that __d_path applies
* Detect the race and relookup the path
*
* The stripping of (deleted) is a hack that could be removed
* with an updated __d_path
*/
do {
tmp = root;
deleted = d_unlinked(path->dentry);
res = __d_path(path, &tmp, buf, buflen);
} while (deleted != d_unlinked(path->dentry));
spin_unlock(&dcache_lock);
*name = res;
/* handle error conditions - and still allow a partial path to
* be returned.
*/
if (IS_ERR(res)) {
error = PTR_ERR(res);
*name = buf;
goto out;
}
if (deleted) {
/* On some filesystems, newly allocated dentries appear to the
* security_path hooks as a deleted dentry except without an
* inode allocated.
*
* Remove the appended deleted text and return as string for
* normal mediation, or auditing. The (deleted) string is
* guarenteed to be added in this case, so just strip it.
*/
buf[buflen - 11] = 0; /* - (len(" (deleted)") +\0) */
if (path->dentry->d_inode && !(flags & PATH_MEDIATE_DELETED)) {
error = -ENOENT;
goto out;
}
}
/* Determine if the path is connected to the expected root */
connected = tmp.dentry == root.dentry && tmp.mnt == root.mnt;
/* If the path is not connected, then remove any leading / that
* __d_path may have returned.
* Unless
* specifically directed to connect the path,
* OR
* if in a chroot and doing chroot relative paths and the path
* resolves to the namespace root (would be connected outside
* of chroot) and specifically directed to connect paths to
* namespace root.
*/
if (!connected &&
!(flags & PATH_CONNECT_PATH) &&
!((flags & PATH_CHROOT_REL) && (flags & PATH_CHROOT_NSCONNECT) &&
(tmp.mnt == current->nsproxy->mnt_ns->root &&
tmp.dentry == current->nsproxy->mnt_ns->root->mnt_root))) {
/* disconnected path, don't return pathname starting with '/' */
error = -ESTALE;
if (*res == '/')
*name = res + 1;
}
out:
path_put(&root);
return error;
}
