[mirror_zfs.git] / module / zcommon / 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.
 */
/*
 * Copyright (c) 2013 by Delphix. All rights reserved.
 */

/*
 * 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/dsl_dir.h>
#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
zfs_component_namecheck(const char *path, namecheck_err_t *why, char *what)
{
	const char *loc;

	if (strlen(path) >= ZFS_MAX_DATASET_NAME_LEN) {
		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 (zfs_component_namecheck(&path[1], why, what));
}

/*
 * Entity 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
entity_namecheck(const char *path, namecheck_err_t *why, char *what)
{
	const char *start, *end;
	int found_delim;

	/*
	 * Make sure the name is not too long.
	 */

	if (strlen(path) >= ZFS_MAX_DATASET_NAME_LEN) {
		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);
	}

	start = path;
	found_delim = 0;
	for (;;) {
		/* Find the end of this component */
		end = start;
		while (*end != '/' && *end != '@' && *end != '#' &&
		    *end != '\0')
			end++;

		if (*end == '\0' && end[-1] == '/') {
			/* trailing slashes are not allowed */
			if (why)
				*why = NAME_ERR_TRAILING_SLASH;
			return (-1);
		}

		/* Validate the contents of this component */
		for (const char *loc = start; loc != end; loc++) {
			if (!valid_char(*loc) && *loc != '%') {
				if (why) {
					*why = NAME_ERR_INVALCHAR;
					*what = *loc;
				}
				return (-1);
			}
		}

		/* Snapshot or bookmark delimiter found */
		if (*end == '@' || *end == '#') {
			/* Multiple delimiters are not allowed */
			if (found_delim != 0) {
				if (why)
					*why = NAME_ERR_MULTIPLE_DELIMITERS;
				return (-1);
			}

			found_delim = 1;
		}

		/* Zero-length components are not allowed */
		if (start == end) {
			if (why)
				*why = NAME_ERR_EMPTY_COMPONENT;
			return (-1);
		}

		/* If we've reached the end of the string, we're OK */
		if (*end == '\0')
			return (0);

		/*
		 * If there is a '/' in a snapshot or bookmark name
		 * then report an error
		 */
		if (*end == '/' && found_delim != 0) {
			if (why)
				*why = NAME_ERR_TRAILING_SLASH;
			return (-1);
		}

		/* Update to the next component */
		start = end + 1;
	}
}

/*
 * Dataset is any entity, except bookmark
 */
int
dataset_namecheck(const char *path, namecheck_err_t *why, char *what)
{
	int ret = entity_namecheck(path, why, what);

	if (ret == 0 && strchr(path, '#') != NULL) {
		if (why != NULL) {
			*why = NAME_ERR_INVALCHAR;
			*what = '#';
		}
		return (-1);
	}

	return (ret);
}

/*
 * 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 >= ZFS_MAX_DATASET_NAME_LEN) {
			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.
	 * If we're creating a pool with version >= SPA_VERSION_DSL_SCRUB (v11)
	 * we need to account for additional space needed by the origin ds which
	 * will also be snapshotted: "poolname"+"/"+"$ORIGIN"+"@"+"$ORIGIN".
	 * Play it safe and enforce this limit even if the pool version is < 11
	 * so it can be upgraded without issues.
	 */
	if (strlen(pool) >= (ZFS_MAX_DATASET_NAME_LEN - 2 -
	    strlen(ORIGIN_DIR_NAME) * 2)) {
		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);
}

#if defined(_KERNEL) && defined(HAVE_SPL)
EXPORT_SYMBOL(pool_namecheck);
EXPORT_SYMBOL(dataset_namecheck);
EXPORT_SYMBOL(zfs_component_namecheck);
#endif
Commit	Line	Data
34dc7c2f BB	1	/*
	2	* CDDL HEADER START
	3	*
	4	* The contents of this file are subject to the terms of the
	5	* Common Development and Distribution License (the "License").
	6	* You may not use this file except in compliance with the License.
	7	*
	8	* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
	9	* or http://www.opensolaris.org/os/licensing.
	10	* See the License for the specific language governing permissions
	11	* and limitations under the License.
	12	*
	13	* When distributing Covered Code, include this CDDL HEADER in each
	14	* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
	15	* If applicable, add the following below this CDDL HEADER, with the
	16	* fields enclosed by brackets "[]" replaced with your own identifying
	17	* information: Portions Copyright [yyyy] [name of copyright owner]
	18	*
	19	* CDDL HEADER END
	20	*/
	21	/*
9babb374	22	* Copyright 2009 Sun Microsystems, Inc. All rights reserved.
34dc7c2f BB	23	* Use is subject to license terms.
34dc7c2f BB	24	*/
da536844 MA	25	/*
	26	* Copyright (c) 2013 by Delphix. All rights reserved.
	27	*/
34dc7c2f	28
34dc7c2f BB	29	/*
	30	* Common name validation routines for ZFS. These routines are shared by the
	31	* userland code as well as the ioctl() layer to ensure that we don't
	32	* inadvertently expose a hole through direct ioctl()s that never gets tested.
	33	* In userland, however, we want significantly more information about _why_ the
	34	* name is invalid. In the kernel, we only care whether it's valid or not.
	35	* Each routine therefore takes a 'namecheck_err_t' which describes exactly why
	36	* the name failed to validate.
	37	*
	38	* Each function returns 0 on success, -1 on error.
	39	*/
	40
	41	#if defined(_KERNEL)
	42	#include <sys/systm.h>
	43	#else
	44	#include <string.h>
	45	#endif
	46
871e0732	47	#include <sys/dsl_dir.h>
34dc7c2f BB	48	#include <sys/param.h>
	49	#include <sys/nvpair.h>
	50	#include "zfs_namecheck.h"
	51	#include "zfs_deleg.h"
	52
	53	static int
	54	valid_char(char c)
	55	{
	56	return ((c >= 'a' && c <= 'z') \|\|
	57	(c >= 'A' && c <= 'Z') \|\|
	58	(c >= '0' && c <= '9') \|\|
b128c09f	59	c == '-' \|\| c == '_' \|\| c == '.' \|\| c == ':' \|\| c == ' ');
34dc7c2f BB	60	}
	61
	62	/*
	63	* Snapshot names must be made up of alphanumeric characters plus the following
	64	* characters:
	65	*
45d1cae3	66	* [-_.: ]
34dc7c2f BB	67	*/
34dc7c2f BB	68	int
da536844	69	zfs_component_namecheck(const char path, namecheck_err_t why, char *what)
34dc7c2f BB	70	{
	71	const char *loc;
	72
eca7b760	73	if (strlen(path) >= ZFS_MAX_DATASET_NAME_LEN) {
34dc7c2f BB	74	if (why)
	75	*why = NAME_ERR_TOOLONG;
	76	return (-1);
	77	}
	78
	79	if (path[0] == '\0') {
	80	if (why)
	81	*why = NAME_ERR_EMPTY_COMPONENT;
	82	return (-1);
	83	}
	84
	85	for (loc = path; *loc; loc++) {
	86	if (!valid_char(*loc)) {
	87	if (why) {
	88	*why = NAME_ERR_INVALCHAR;
	89	what = loc;
	90	}
	91	return (-1);
	92	}
	93	}
	94	return (0);
	95	}
	96
	97
	98	/*
	99	* Permissions set name must start with the letter '@' followed by the
	100	* same character restrictions as snapshot names, except that the name
	101	* cannot exceed 64 characters.
	102	*/
	103	int
	104	permset_namecheck(const char path, namecheck_err_t why, char *what)
	105	{
	106	if (strlen(path) >= ZFS_PERMSET_MAXLEN) {
	107	if (why)
	108	*why = NAME_ERR_TOOLONG;
	109	return (-1);
	110	}
	111
	112	if (path[0] != '@') {
	113	if (why) {
	114	*why = NAME_ERR_NO_AT;
	115	*what = path[0];
	116	}
	117	return (-1);
	118	}
	119
da536844	120	return (zfs_component_namecheck(&path[1], why, what));
34dc7c2f BB	121	}
	122
	123	/*
aeacdefe	124	* Entity names must be of the following form:
34dc7c2f	125	*
aeacdefe	126	* [component/]*[component][(@\|#)component]?
34dc7c2f BB	127	*
	128	* Where each component is made up of alphanumeric characters plus the following
	129	* characters:
	130	*
	131	* [-_.:%]
	132	*
	133	* We allow '%' here as we use that character internally to create unique
	134	* names for temporary clones (for online recv).
	135	*/
	136	int
aeacdefe	137	entity_namecheck(const char path, namecheck_err_t why, char *what)
34dc7c2f	138	{
1c27024e	139	const char start, end;
aeacdefe	140	int found_delim;
34dc7c2f BB	141
	142	/*
	143	* Make sure the name is not too long.
34dc7c2f	144	*/
1c27024e	145
eca7b760	146	if (strlen(path) >= ZFS_MAX_DATASET_NAME_LEN) {
34dc7c2f BB	147	if (why)
	148	*why = NAME_ERR_TOOLONG;
	149	return (-1);
	150	}
	151
	152	/* Explicitly check for a leading slash. */
	153	if (path[0] == '/') {
	154	if (why)
	155	*why = NAME_ERR_LEADING_SLASH;
	156	return (-1);
	157	}
	158
	159	if (path[0] == '\0') {
	160	if (why)
	161	*why = NAME_ERR_EMPTY_COMPONENT;
	162	return (-1);
	163	}
	164
aeacdefe GM	165	start = path;
aeacdefe GM	166	found_delim = 0;
34dc7c2f BB	167	for (;;) {
34dc7c2f BB	168	/* Find the end of this component */
aeacdefe GM	169	end = start;
	170	while (end != '/' && end != '@' && *end != '#' &&
	171	*end != '\0')
34dc7c2f BB	172	end++;
	173
	174	if (*end == '\0' && end[-1] == '/') {
	175	/* trailing slashes are not allowed */
	176	if (why)
	177	*why = NAME_ERR_TRAILING_SLASH;
	178	return (-1);
	179	}
	180
34dc7c2f	181	/* Validate the contents of this component */
1c27024e	182	for (const char *loc = start; loc != end; loc++) {
34dc7c2f BB	183	if (!valid_char(loc) && loc != '%') {
	184	if (why) {
	185	*why = NAME_ERR_INVALCHAR;
	186	what = loc;
	187	}
	188	return (-1);
	189	}
34dc7c2f BB	190	}
34dc7c2f BB	191
aeacdefe GM	192	/* Snapshot or bookmark delimiter found */
	193	if (end == '@' \|\| end == '#') {
	194	/* Multiple delimiters are not allowed */
	195	if (found_delim != 0) {
34dc7c2f	196	if (why)
aeacdefe	197	*why = NAME_ERR_MULTIPLE_DELIMITERS;
34dc7c2f BB	198	return (-1);
	199	}
	200
aeacdefe	201	found_delim = 1;
34dc7c2f BB	202	}
34dc7c2f BB	203
aeacdefe GM	204	/* Zero-length components are not allowed */
	205	if (start == end) {
	206	if (why)
	207	*why = NAME_ERR_EMPTY_COMPONENT;
	208	return (-1);
	209	}
	210
	211	/* If we've reached the end of the string, we're OK */
	212	if (*end == '\0')
	213	return (0);
	214
34dc7c2f	215	/*
aeacdefe	216	* If there is a '/' in a snapshot or bookmark name
34dc7c2f BB	217	* then report an error
34dc7c2f BB	218	*/
aeacdefe	219	if (*end == '/' && found_delim != 0) {
34dc7c2f BB	220	if (why)
	221	*why = NAME_ERR_TRAILING_SLASH;
	222	return (-1);
	223	}
	224
	225	/* Update to the next component */
aeacdefe	226	start = end + 1;
34dc7c2f BB	227	}
	228	}
	229
aeacdefe GM	230	/*
	231	* Dataset is any entity, except bookmark
	232	*/
	233	int
	234	dataset_namecheck(const char path, namecheck_err_t why, char *what)
	235	{
	236	int ret = entity_namecheck(path, why, what);
	237
	238	if (ret == 0 && strchr(path, '#') != NULL) {
	239	if (why != NULL) {
	240	*why = NAME_ERR_INVALCHAR;
	241	*what = '#';
	242	}
	243	return (-1);
	244	}
	245
	246	return (ret);
	247	}
34dc7c2f BB	248
	249	/*
	250	* mountpoint names must be of the following form:
	251	*
	252	* /[component][/]*[component][/]
	253	*/
	254	int
	255	mountpoint_namecheck(const char path, namecheck_err_t why)
	256	{
	257	const char start, end;
	258
	259	/*
	260	* Make sure none of the mountpoint component names are too long.
	261	* If a component name is too long then the mkdir of the mountpoint
	262	* will fail but then the mountpoint property will be set to a value
	263	* that can never be mounted. Better to fail before setting the prop.
	264	* Extra slashes are OK, they will be tossed by the mountpoint mkdir.
	265	*/
	266
	267	if (path == NULL \|\| *path != '/') {
	268	if (why)
	269	*why = NAME_ERR_LEADING_SLASH;
	270	return (-1);
	271	}
	272
	273	/* Skip leading slash */
	274	start = &path[1];
	275	do {
	276	end = start;
	277	while (end != '/' && end != '\0')
	278	end++;
	279
eca7b760	280	if (end - start >= ZFS_MAX_DATASET_NAME_LEN) {
34dc7c2f BB	281	if (why)
	282	*why = NAME_ERR_TOOLONG;
	283	return (-1);
	284	}
	285	start = end + 1;
	286
	287	} while (*end != '\0');
	288
	289	return (0);
	290	}
	291
	292	/*
	293	* For pool names, we have the same set of valid characters as described in
	294	* dataset names, with the additional restriction that the pool name must begin
	295	* with a letter. The pool names 'raidz' and 'mirror' are also reserved names
	296	* that cannot be used.
	297	*/
	298	int
	299	pool_namecheck(const char pool, namecheck_err_t why, char *what)
	300	{
	301	const char *c;
	302
	303	/*
	304	* Make sure the name is not too long.
871e0732	305	* If we're creating a pool with version >= SPA_VERSION_DSL_SCRUB (v11)
	306	* we need to account for additional space needed by the origin ds which
	307	* will also be snapshotted: "poolname"+"/"+"$ORIGIN"+"@"+"$ORIGIN".
	308	* Play it safe and enforce this limit even if the pool version is < 11
	309	* so it can be upgraded without issues.
34dc7c2f	310	*/
871e0732	311	if (strlen(pool) >= (ZFS_MAX_DATASET_NAME_LEN - 2 -
871e0732	312	strlen(ORIGIN_DIR_NAME) * 2)) {
34dc7c2f BB	313	if (why)
	314	*why = NAME_ERR_TOOLONG;
	315	return (-1);
	316	}
	317
	318	c = pool;
	319	while (*c != '\0') {
	320	if (!valid_char(*c)) {
	321	if (why) {
	322	*why = NAME_ERR_INVALCHAR;
	323	what = c;
	324	}
	325	return (-1);
	326	}
	327	c++;
	328	}
	329
	330	if (!(pool >= 'a' && pool <= 'z') &&
	331	!(pool >= 'A' && pool <= 'Z')) {
	332	if (why)
	333	*why = NAME_ERR_NOLETTER;
	334	return (-1);
	335	}
	336
	337	if (strcmp(pool, "mirror") == 0 \|\| strcmp(pool, "raidz") == 0) {
	338	if (why)
	339	*why = NAME_ERR_RESERVED;
	340	return (-1);
	341	}
	342
	343	if (pool[0] == 'c' && (pool[1] >= '0' && pool[1] <= '9')) {
	344	if (why)
	345	*why = NAME_ERR_DISKLIKE;
	346	return (-1);
	347	}
	348
	349	return (0);
	350	}
c28b2279 BB	351
c28b2279 BB	352	#if defined(_KERNEL) && defined(HAVE_SPL)
c28b2279 BB	353	EXPORT_SYMBOL(pool_namecheck);
c28b2279 BB	354	EXPORT_SYMBOL(dataset_namecheck);
da536844	355	EXPORT_SYMBOL(zfs_component_namecheck);
c28b2279	356	#endif