OpenSolaris_b135/common/zfs/zfs_namecheck.c
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2009 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/*
* Common name validation routines for ZFS. These routines are shared by the
* userland code as well as the ioctl() layer to ensure that we don't
* inadvertently expose a hole through direct ioctl()s that never gets tested.
* In userland, however, we want significantly more information about _why_ the
* name is invalid. In the kernel, we only care whether it's valid or not.
* Each routine therefore takes a 'namecheck_err_t' which describes exactly why
* the name failed to validate.
*
* Each function returns 0 on success, -1 on error.
*/
#if defined(_KERNEL)
#include <sys/systm.h>
#else
#include <string.h>
#endif
#include <sys/param.h>
#include <sys/nvpair.h>
#include "zfs_namecheck.h"
#include "zfs_deleg.h"
static int
valid_char(char c)
{
return ((c >= 'a' && c <= 'z') ||
(c >= 'A' && c <= 'Z') ||
(c >= '0' && c <= '9') ||
c == '-' || c == '_' || c == '.' || c == ':' || c == ' ');
}
/*
* Snapshot names must be made up of alphanumeric characters plus the following
* characters:
*
* [-_.: ]
*/
int
snapshot_namecheck(const char *path, namecheck_err_t *why, char *what)
{
const char *loc;
if (strlen(path) >= MAXNAMELEN) {
if (why)
*why = NAME_ERR_TOOLONG;
return (-1);
}
if (path[0] == '\0') {
if (why)
*why = NAME_ERR_EMPTY_COMPONENT;
return (-1);
}
for (loc = path; *loc; loc++) {
if (!valid_char(*loc)) {
if (why) {
*why = NAME_ERR_INVALCHAR;
*what = *loc;
}
return (-1);
}
}
return (0);
}
/*
* Permissions set name must start with the letter '@' followed by the
* same character restrictions as snapshot names, except that the name
* cannot exceed 64 characters.
*/
int
permset_namecheck(const char *path, namecheck_err_t *why, char *what)
{
if (strlen(path) >= ZFS_PERMSET_MAXLEN) {
if (why)
*why = NAME_ERR_TOOLONG;
return (-1);
}
if (path[0] != '@') {
if (why) {
*why = NAME_ERR_NO_AT;
*what = path[0];
}
return (-1);
}
return (snapshot_namecheck(&path[1], why, what));
}
/*
* Dataset names must be of the following form:
*
* [component][/]*[component][@component]
*
* Where each component is made up of alphanumeric characters plus the following
* characters:
*
* [-_.:%]
*
* We allow '%' here as we use that character internally to create unique
* names for temporary clones (for online recv).
*/
int
dataset_namecheck(const char *path, namecheck_err_t *why, char *what)
{
const char *loc, *end;
int found_snapshot;
/*
* Make sure the name is not too long.
*
* ZFS_MAXNAMELEN is the maximum dataset length used in the userland
* which is the same as MAXNAMELEN used in the kernel.
* If ZFS_MAXNAMELEN value is changed, make sure to cleanup all
* places using MAXNAMELEN.
*/
if (strlen(path) >= MAXNAMELEN) {
if (why)
*why = NAME_ERR_TOOLONG;
return (-1);
}
/* Explicitly check for a leading slash. */
if (path[0] == '/') {
if (why)
*why = NAME_ERR_LEADING_SLASH;
return (-1);
}
if (path[0] == '\0') {
if (why)
*why = NAME_ERR_EMPTY_COMPONENT;
return (-1);
}
loc = path;
found_snapshot = 0;
for (;;) {
/* Find the end of this component */
end = loc;
while (*end != '/' && *end != '@' && *end != '\0')
end++;
if (*end == '\0' && end[-1] == '/') {
/* trailing slashes are not allowed */
if (why)
*why = NAME_ERR_TRAILING_SLASH;
return (-1);
}
/* Zero-length components are not allowed */
if (loc == end) {
if (why) {
/*
* Make sure this is really a zero-length
* component and not a '@@'.
*/
if (*end == '@' && found_snapshot) {
*why = NAME_ERR_MULTIPLE_AT;
} else {
*why = NAME_ERR_EMPTY_COMPONENT;
}
}
return (-1);
}
/* Validate the contents of this component */
while (loc != end) {
if (!valid_char(*loc) && *loc != '%') {
if (why) {
*why = NAME_ERR_INVALCHAR;
*what = *loc;
}
return (-1);
}
loc++;
}
/* If we've reached the end of the string, we're OK */
if (*end == '\0')
return (0);
if (*end == '@') {
/*
* If we've found an @ symbol, indicate that we're in
* the snapshot component, and report a second '@'
* character as an error.
*/
if (found_snapshot) {
if (why)
*why = NAME_ERR_MULTIPLE_AT;
return (-1);
}
found_snapshot = 1;
}
/*
* If there is a '/' in a snapshot name
* then report an error
*/
if (*end == '/' && found_snapshot) {
if (why)
*why = NAME_ERR_TRAILING_SLASH;
return (-1);
}
/* Update to the next component */
loc = end + 1;
}
}
/*
* mountpoint names must be of the following form:
*
* /[component][/]*[component][/]
*/
int
mountpoint_namecheck(const char *path, namecheck_err_t *why)
{
const char *start, *end;
/*
* Make sure none of the mountpoint component names are too long.
* If a component name is too long then the mkdir of the mountpoint
* will fail but then the mountpoint property will be set to a value
* that can never be mounted. Better to fail before setting the prop.
* Extra slashes are OK, they will be tossed by the mountpoint mkdir.
*/
if (path == NULL || *path != '/') {
if (why)
*why = NAME_ERR_LEADING_SLASH;
return (-1);
}
/* Skip leading slash */
start = &path[1];
do {
end = start;
while (*end != '/' && *end != '\0')
end++;
if (end - start >= MAXNAMELEN) {
if (why)
*why = NAME_ERR_TOOLONG;
return (-1);
}
start = end + 1;
} while (*end != '\0');
return (0);
}
/*
* For pool names, we have the same set of valid characters as described in
* dataset names, with the additional restriction that the pool name must begin
* with a letter. The pool names 'raidz' and 'mirror' are also reserved names
* that cannot be used.
*/
int
pool_namecheck(const char *pool, namecheck_err_t *why, char *what)
{
const char *c;
/*
* Make sure the name is not too long.
*
* ZPOOL_MAXNAMELEN is the maximum pool length used in the userland
* which is the same as MAXNAMELEN used in the kernel.
* If ZPOOL_MAXNAMELEN value is changed, make sure to cleanup all
* places using MAXNAMELEN.
*/
if (strlen(pool) >= MAXNAMELEN) {
if (why)
*why = NAME_ERR_TOOLONG;
return (-1);
}
c = pool;
while (*c != '\0') {
if (!valid_char(*c)) {
if (why) {
*why = NAME_ERR_INVALCHAR;
*what = *c;
}
return (-1);
}
c++;
}
if (!(*pool >= 'a' && *pool <= 'z') &&
!(*pool >= 'A' && *pool <= 'Z')) {
if (why)
*why = NAME_ERR_NOLETTER;
return (-1);
}
if (strcmp(pool, "mirror") == 0 || strcmp(pool, "raidz") == 0) {
if (why)
*why = NAME_ERR_RESERVED;
return (-1);
}
if (pool[0] == 'c' && (pool[1] >= '0' && pool[1] <= '9')) {
if (why)
*why = NAME_ERR_DISKLIKE;
return (-1);
}
return (0);
}