[mirror_ubuntu-artful-kernel.git] / net / netlink / attr.c

/*
 * NETLINK      Netlink attributes
 *
 * 		Authors:	Thomas Graf <tgraf@suug.ch>
 * 				Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/jiffies.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/string.h>
#include <linux/types.h>
#include <net/netlink.h>

static u16 nla_attr_minlen[NLA_TYPE_MAX+1] __read_mostly = {
	[NLA_U8]	= sizeof(u8),
	[NLA_U16]	= sizeof(u16),
	[NLA_U32]	= sizeof(u32),
	[NLA_U64]	= sizeof(u64),
	[NLA_NESTED]	= NLA_HDRLEN,
};

static int validate_nla(struct nlattr *nla, int maxtype,
			struct nla_policy *policy)
{
	struct nla_policy *pt;
	int minlen = 0, attrlen = nla_len(nla);

	if (nla->nla_type <= 0 || nla->nla_type > maxtype)
		return 0;

	pt = &policy[nla->nla_type];

	BUG_ON(pt->type > NLA_TYPE_MAX);

	switch (pt->type) {
	case NLA_FLAG:
		if (attrlen > 0)
			return -ERANGE;
		break;

	case NLA_NUL_STRING:
		if (pt->len)
			minlen = min_t(int, attrlen, pt->len + 1);
		else
			minlen = attrlen;

		if (!minlen || memchr(nla_data(nla), '\0', minlen) == NULL)
			return -EINVAL;
		/* fall through */

	case NLA_STRING:
		if (attrlen < 1)
			return -ERANGE;

		if (pt->len) {
			char *buf = nla_data(nla);

			if (buf[attrlen - 1] == '\0')
				attrlen--;

			if (attrlen > pt->len)
				return -ERANGE;
		}
		break;

	case NLA_BINARY:
		if (pt->len && attrlen > pt->len)
			return -ERANGE;
		break;

	default:
		if (pt->len)
			minlen = pt->len;
		else if (pt->type != NLA_UNSPEC)
			minlen = nla_attr_minlen[pt->type];

		if (attrlen < minlen)
			return -ERANGE;
	}

	return 0;
}

/**
 * nla_validate - Validate a stream of attributes
 * @head: head of attribute stream
 * @len: length of attribute stream
 * @maxtype: maximum attribute type to be expected
 * @policy: validation policy
 *
 * Validates all attributes in the specified attribute stream against the
 * specified policy. Attributes with a type exceeding maxtype will be
 * ignored. See documenation of struct nla_policy for more details.
 *
 * Returns 0 on success or a negative error code.
 */
int nla_validate(struct nlattr *head, int len, int maxtype,
		 struct nla_policy *policy)
{
	struct nlattr *nla;
	int rem, err;

	nla_for_each_attr(nla, head, len, rem) {
		err = validate_nla(nla, maxtype, policy);
		if (err < 0)
			goto errout;
	}

	err = 0;
errout:
	return err;
}

/**
 * nla_parse - Parse a stream of attributes into a tb buffer
 * @tb: destination array with maxtype+1 elements
 * @maxtype: maximum attribute type to be expected
 * @head: head of attribute stream
 * @len: length of attribute stream
 *
 * Parses a stream of attributes and stores a pointer to each attribute in
 * the tb array accessable via the attribute type. Attributes with a type
 * exceeding maxtype will be silently ignored for backwards compatibility
 * reasons. policy may be set to NULL if no validation is required.
 *
 * Returns 0 on success or a negative error code.
 */
int nla_parse(struct nlattr *tb[], int maxtype, struct nlattr *head, int len,
	      struct nla_policy *policy)
{
	struct nlattr *nla;
	int rem, err;

	memset(tb, 0, sizeof(struct nlattr *) * (maxtype + 1));

	nla_for_each_attr(nla, head, len, rem) {
		u16 type = nla->nla_type;

		if (type > 0 && type <= maxtype) {
			if (policy) {
				err = validate_nla(nla, maxtype, policy);
				if (err < 0)
					goto errout;
			}

			tb[type] = nla;
		}
	}

	if (unlikely(rem > 0))
		printk(KERN_WARNING "netlink: %d bytes leftover after parsing "
		       "attributes.\n", rem);

	err = 0;
errout:
	return err;
}

/**
 * nla_find - Find a specific attribute in a stream of attributes
 * @head: head of attribute stream
 * @len: length of attribute stream
 * @attrtype: type of attribute to look for
 *
 * Returns the first attribute in the stream matching the specified type.
 */
struct nlattr *nla_find(struct nlattr *head, int len, int attrtype)
{
	struct nlattr *nla;
	int rem;

	nla_for_each_attr(nla, head, len, rem)
		if (nla->nla_type == attrtype)
			return nla;

	return NULL;
}

/**
 * nla_strlcpy - Copy string attribute payload into a sized buffer
 * @dst: where to copy the string to
 * @src: attribute to copy the string from
 * @dstsize: size of destination buffer
 *
 * Copies at most dstsize - 1 bytes into the destination buffer.
 * The result is always a valid NUL-terminated string. Unlike
 * strlcpy the destination buffer is always padded out.
 *
 * Returns the length of the source buffer.
 */
size_t nla_strlcpy(char *dst, const struct nlattr *nla, size_t dstsize)
{
	size_t srclen = nla_len(nla);
	char *src = nla_data(nla);

	if (srclen > 0 && src[srclen - 1] == '\0')
		srclen--;

	if (dstsize > 0) {
		size_t len = (srclen >= dstsize) ? dstsize - 1 : srclen;

		memset(dst, 0, dstsize);
		memcpy(dst, src, len);
	}

	return srclen;
}

/**
 * nla_memcpy - Copy a netlink attribute into another memory area
 * @dest: where to copy to memcpy
 * @src: netlink attribute to copy from
 * @count: size of the destination area
 *
 * Note: The number of bytes copied is limited by the length of
 *       attribute's payload. memcpy
 *
 * Returns the number of bytes copied.
 */
int nla_memcpy(void *dest, struct nlattr *src, int count)
{
	int minlen = min_t(int, count, nla_len(src));

	memcpy(dest, nla_data(src), minlen);

	return minlen;
}

/**
 * nla_memcmp - Compare an attribute with sized memory area
 * @nla: netlink attribute
 * @data: memory area
 * @size: size of memory area
 */
int nla_memcmp(const struct nlattr *nla, const void *data,
			     size_t size)
{
	int d = nla_len(nla) - size;

	if (d == 0)
		d = memcmp(nla_data(nla), data, size);

	return d;
}

/**
 * nla_strcmp - Compare a string attribute against a string
 * @nla: netlink string attribute
 * @str: another string
 */
int nla_strcmp(const struct nlattr *nla, const char *str)
{
	int len = strlen(str) + 1;
	int d = nla_len(nla) - len;

	if (d == 0)
		d = memcmp(nla_data(nla), str, len);

	return d;
}

/**
 * __nla_reserve - reserve room for attribute on the skb
 * @skb: socket buffer to reserve room on
 * @attrtype: attribute type
 * @attrlen: length of attribute payload
 *
 * Adds a netlink attribute header to a socket buffer and reserves
 * room for the payload but does not copy it.
 *
 * The caller is responsible to ensure that the skb provides enough
 * tailroom for the attribute header and payload.
 */
struct nlattr *__nla_reserve(struct sk_buff *skb, int attrtype, int attrlen)
{
	struct nlattr *nla;

	nla = (struct nlattr *) skb_put(skb, nla_total_size(attrlen));
	nla->nla_type = attrtype;
	nla->nla_len = nla_attr_size(attrlen);

	memset((unsigned char *) nla + nla->nla_len, 0, nla_padlen(attrlen));

	return nla;
}

/**
 * __nla_reserve_nohdr - reserve room for attribute without header
 * @skb: socket buffer to reserve room on
 * @attrlen: length of attribute payload
 *
 * Reserves room for attribute payload without a header.
 *
 * The caller is responsible to ensure that the skb provides enough
 * tailroom for the payload.
 */
void *__nla_reserve_nohdr(struct sk_buff *skb, int attrlen)
{
	void *start;

	start = skb_put(skb, NLA_ALIGN(attrlen));
	memset(start, 0, NLA_ALIGN(attrlen));

	return start;
}

/**
 * nla_reserve - reserve room for attribute on the skb
 * @skb: socket buffer to reserve room on
 * @attrtype: attribute type
 * @attrlen: length of attribute payload
 *
 * Adds a netlink attribute header to a socket buffer and reserves
 * room for the payload but does not copy it.
 *
 * Returns NULL if the tailroom of the skb is insufficient to store
 * the attribute header and payload.
 */
struct nlattr *nla_reserve(struct sk_buff *skb, int attrtype, int attrlen)
{
	if (unlikely(skb_tailroom(skb) < nla_total_size(attrlen)))
		return NULL;

	return __nla_reserve(skb, attrtype, attrlen);
}

/**
 * nla_reserve - reserve room for attribute without header
 * @skb: socket buffer to reserve room on
 * @len: length of attribute payload
 *
 * Reserves room for attribute payload without a header.
 *
 * Returns NULL if the tailroom of the skb is insufficient to store
 * the attribute payload.
 */
void *nla_reserve_nohdr(struct sk_buff *skb, int attrlen)
{
	if (unlikely(skb_tailroom(skb) < NLA_ALIGN(attrlen)))
		return NULL;

	return __nla_reserve_nohdr(skb, attrlen);
}

/**
 * __nla_put - Add a netlink attribute to a socket buffer
 * @skb: socket buffer to add attribute to
 * @attrtype: attribute type
 * @attrlen: length of attribute payload
 * @data: head of attribute payload
 *
 * The caller is responsible to ensure that the skb provides enough
 * tailroom for the attribute header and payload.
 */
void __nla_put(struct sk_buff *skb, int attrtype, int attrlen,
			     const void *data)
{
	struct nlattr *nla;

	nla = __nla_reserve(skb, attrtype, attrlen);
	memcpy(nla_data(nla), data, attrlen);
}

/**
 * __nla_put_nohdr - Add a netlink attribute without header
 * @skb: socket buffer to add attribute to
 * @attrlen: length of attribute payload
 * @data: head of attribute payload
 *
 * The caller is responsible to ensure that the skb provides enough
 * tailroom for the attribute payload.
 */
void __nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data)
{
	void *start;

	start = __nla_reserve_nohdr(skb, attrlen);
	memcpy(start, data, attrlen);
}

/**
 * nla_put - Add a netlink attribute to a socket buffer
 * @skb: socket buffer to add attribute to
 * @attrtype: attribute type
 * @attrlen: length of attribute payload
 * @data: head of attribute payload
 *
 * Returns -1 if the tailroom of the skb is insufficient to store
 * the attribute header and payload.
 */
int nla_put(struct sk_buff *skb, int attrtype, int attrlen, const void *data)
{
	if (unlikely(skb_tailroom(skb) < nla_total_size(attrlen)))
		return -1;

	__nla_put(skb, attrtype, attrlen, data);
	return 0;
}

/**
 * nla_put_nohdr - Add a netlink attribute without header
 * @skb: socket buffer to add attribute to
 * @attrlen: length of attribute payload
 * @data: head of attribute payload
 *
 * Returns -1 if the tailroom of the skb is insufficient to store
 * the attribute payload.
 */
int nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data)
{
	if (unlikely(skb_tailroom(skb) < NLA_ALIGN(attrlen)))
		return -1;

	__nla_put_nohdr(skb, attrlen, data);
	return 0;
}

EXPORT_SYMBOL(nla_validate);
EXPORT_SYMBOL(nla_parse);
EXPORT_SYMBOL(nla_find);
EXPORT_SYMBOL(nla_strlcpy);
EXPORT_SYMBOL(__nla_reserve);
EXPORT_SYMBOL(__nla_reserve_nohdr);
EXPORT_SYMBOL(nla_reserve);
EXPORT_SYMBOL(nla_reserve_nohdr);
EXPORT_SYMBOL(__nla_put);
EXPORT_SYMBOL(__nla_put_nohdr);
EXPORT_SYMBOL(nla_put);
EXPORT_SYMBOL(nla_put_nohdr);
EXPORT_SYMBOL(nla_memcpy);
EXPORT_SYMBOL(nla_memcmp);
EXPORT_SYMBOL(nla_strcmp);
Commit	Line	Data
bfa83a9e TG	1	/*
	2	* NETLINK Netlink attributes
	3	*
	4	* Authors: Thomas Graf <tgraf@suug.ch>
	5	* Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
	6	*/
	7
bfa83a9e TG	8	#include <linux/module.h>
	9	#include <linux/kernel.h>
	10	#include <linux/errno.h>
	11	#include <linux/jiffies.h>
	12	#include <linux/netdevice.h>
	13	#include <linux/skbuff.h>
	14	#include <linux/string.h>
	15	#include <linux/types.h>
	16	#include <net/netlink.h>
	17
	18	static u16 nla_attr_minlen[NLA_TYPE_MAX+1] __read_mostly = {
	19	[NLA_U8] = sizeof(u8),
	20	[NLA_U16] = sizeof(u16),
	21	[NLA_U32] = sizeof(u32),
	22	[NLA_U64] = sizeof(u64),
bfa83a9e TG	23	[NLA_NESTED] = NLA_HDRLEN,
	24	};
	25
	26	static int validate_nla(struct nlattr *nla, int maxtype,
	27	struct nla_policy *policy)
	28	{
	29	struct nla_policy *pt;
a5531a5d	30	int minlen = 0, attrlen = nla_len(nla);
bfa83a9e TG	31
	32	if (nla->nla_type <= 0 \|\| nla->nla_type > maxtype)
	33	return 0;
	34
	35	pt = &policy[nla->nla_type];
	36
	37	BUG_ON(pt->type > NLA_TYPE_MAX);
	38
a5531a5d TG	39	switch (pt->type) {
	40	case NLA_FLAG:
	41	if (attrlen > 0)
	42	return -ERANGE;
	43	break;
bfa83a9e	44
a5531a5d TG	45	case NLA_NUL_STRING:
	46	if (pt->len)
	47	minlen = min_t(int, attrlen, pt->len + 1);
	48	else
	49	minlen = attrlen;
bfa83a9e	50
a5531a5d TG	51	if (!minlen \|\| memchr(nla_data(nla), '\0', minlen) == NULL)
	52	return -EINVAL;
	53	/* fall through */
	54
	55	case NLA_STRING:
	56	if (attrlen < 1)
	57	return -ERANGE;
	58
	59	if (pt->len) {
	60	char *buf = nla_data(nla);
	61
	62	if (buf[attrlen - 1] == '\0')
	63	attrlen--;
	64
	65	if (attrlen > pt->len)
	66	return -ERANGE;
	67	}
	68	break;
	69
d30045a0 JB	70	case NLA_BINARY:
	71	if (pt->len && attrlen > pt->len)
	72	return -ERANGE;
	73	break;
	74
a5531a5d TG	75	default:
	76	if (pt->len)
	77	minlen = pt->len;
	78	else if (pt->type != NLA_UNSPEC)
	79	minlen = nla_attr_minlen[pt->type];
	80
	81	if (attrlen < minlen)
	82	return -ERANGE;
	83	}
bfa83a9e TG	84
	85	return 0;
	86	}
	87
	88	/**
	89	* nla_validate - Validate a stream of attributes
	90	* @head: head of attribute stream
	91	* @len: length of attribute stream
	92	* @maxtype: maximum attribute type to be expected
	93	* @policy: validation policy
	94	*
	95	* Validates all attributes in the specified attribute stream against the
	96	* specified policy. Attributes with a type exceeding maxtype will be
	97	* ignored. See documenation of struct nla_policy for more details.
	98	*
	99	* Returns 0 on success or a negative error code.
	100	*/
	101	int nla_validate(struct nlattr *head, int len, int maxtype,
	102	struct nla_policy *policy)
	103	{
	104	struct nlattr *nla;
	105	int rem, err;
	106
	107	nla_for_each_attr(nla, head, len, rem) {
	108	err = validate_nla(nla, maxtype, policy);
	109	if (err < 0)
	110	goto errout;
	111	}
	112
	113	err = 0;
	114	errout:
	115	return err;
	116	}
	117
	118	/**
	119	* nla_parse - Parse a stream of attributes into a tb buffer
	120	* @tb: destination array with maxtype+1 elements
	121	* @maxtype: maximum attribute type to be expected
	122	* @head: head of attribute stream
	123	* @len: length of attribute stream
	124	*
	125	* Parses a stream of attributes and stores a pointer to each attribute in
	126	* the tb array accessable via the attribute type. Attributes with a type
	127	* exceeding maxtype will be silently ignored for backwards compatibility
	128	* reasons. policy may be set to NULL if no validation is required.
	129	*
	130	* Returns 0 on success or a negative error code.
	131	*/
	132	int nla_parse(struct nlattr tb[], int maxtype, struct nlattr head, int len,
	133	struct nla_policy *policy)
	134	{
	135	struct nlattr *nla;
	136	int rem, err;
	137
	138	memset(tb, 0, sizeof(struct nlattr ) (maxtype + 1));
	139
	140	nla_for_each_attr(nla, head, len, rem) {
	141	u16 type = nla->nla_type;
	142
	143	if (type > 0 && type <= maxtype) {
	144	if (policy) {
	145	err = validate_nla(nla, maxtype, policy);
	146	if (err < 0)
	147	goto errout;
148	}
149
150	tb[type] = nla;
151	}
152	}
153
154	if (unlikely(rem > 0))
155	printk(KERN_WARNING "netlink: %d bytes leftover after parsing "
156	"attributes.\n", rem);
157
158	err = 0;
159	errout:
160	return err;
161	}
162
163	/**
164	* nla_find - Find a specific attribute in a stream of attributes
165	* @head: head of attribute stream
166	* @len: length of attribute stream
167	* @attrtype: type of attribute to look for
168	*
169	* Returns the first attribute in the stream matching the specified type.
170	*/
171	struct nlattr nla_find(struct nlattr head, int len, int attrtype)
172	{
173	struct nlattr *nla;
174	int rem;
175
176	nla_for_each_attr(nla, head, len, rem)
177	if (nla->nla_type == attrtype)
178	return nla;
179
180	return NULL;
181	}
182
183	/**
184	* nla_strlcpy - Copy string attribute payload into a sized buffer
185	* @dst: where to copy the string to
186	* @src: attribute to copy the string from
187	* @dstsize: size of destination buffer
188	*
189	* Copies at most dstsize - 1 bytes into the destination buffer.
190	* The result is always a valid NUL-terminated string. Unlike
191	* strlcpy the destination buffer is always padded out.
192	*
193	* Returns the length of the source buffer.
194	*/
195	size_t nla_strlcpy(char dst, const struct nlattr nla, size_t dstsize)
196	{
197	size_t srclen = nla_len(nla);
198	char *src = nla_data(nla);
199
200	if (srclen > 0 && src[srclen - 1] == '\0')
201	srclen--;
202
203	if (dstsize > 0) {
204	size_t len = (srclen >= dstsize) ? dstsize - 1 : srclen;
205
206	memset(dst, 0, dstsize);
207	memcpy(dst, src, len);
208	}
209
210	return srclen;
211	}
212
213	/**
214	* nla_memcpy - Copy a netlink attribute into another memory area
215	* @dest: where to copy to memcpy
216	* @src: netlink attribute to copy from
217	* @count: size of the destination area
218	*
219	* Note: The number of bytes copied is limited by the length of
220	* attribute's payload. memcpy
221	*
222	* Returns the number of bytes copied.
223	*/
224	int nla_memcpy(void dest, struct nlattr src, int count)
225	{
226	int minlen = min_t(int, count, nla_len(src));
227
228	memcpy(dest, nla_data(src), minlen);
229
230	return minlen;
231	}
232
233	/**
234	* nla_memcmp - Compare an attribute with sized memory area
235	* @nla: netlink attribute
236	* @data: memory area
237	* @size: size of memory area
238	*/
239	int nla_memcmp(const struct nlattr nla, const void data,
240	size_t size)
241	{
242	int d = nla_len(nla) - size;
243
244	if (d == 0)
245	d = memcmp(nla_data(nla), data, size);
246
247	return d;
248	}
249
250	/**
251	* nla_strcmp - Compare a string attribute against a string
252	* @nla: netlink string attribute
253	* @str: another string
254	*/
255	int nla_strcmp(const struct nlattr nla, const char str)
256	{
257	int len = strlen(str) + 1;
258	int d = nla_len(nla) - len;
259
260	if (d == 0)
261	d = memcmp(nla_data(nla), str, len);
262
263	return d;
264	}
265
266	/**
267	* __nla_reserve - reserve room for attribute on the skb
268	* @skb: socket buffer to reserve room on
269	* @attrtype: attribute type
270	* @attrlen: length of attribute payload
271	*
272	* Adds a netlink attribute header to a socket buffer and reserves
273	* room for the payload but does not copy it.
274	*
275	* The caller is responsible to ensure that the skb provides enough
276	* tailroom for the attribute header and payload.
277	*/
278	struct nlattr __nla_reserve(struct sk_buff skb, int attrtype, int attrlen)
279	{
280	struct nlattr *nla;
281
282	nla = (struct nlattr *) skb_put(skb, nla_total_size(attrlen));
283	nla->nla_type = attrtype;
284	nla->nla_len = nla_attr_size(attrlen);
285
286	memset((unsigned char *) nla + nla->nla_len, 0, nla_padlen(attrlen));
287
288	return nla;
289	}
290
fe4944e5 TG	291	/**
	292	* __nla_reserve_nohdr - reserve room for attribute without header
	293	* @skb: socket buffer to reserve room on
	294	* @attrlen: length of attribute payload
	295	*
	296	* Reserves room for attribute payload without a header.
	297	*
	298	* The caller is responsible to ensure that the skb provides enough
	299	* tailroom for the payload.
	300	*/
	301	void __nla_reserve_nohdr(struct sk_buff skb, int attrlen)
	302	{
	303	void *start;
	304
	305	start = skb_put(skb, NLA_ALIGN(attrlen));
	306	memset(start, 0, NLA_ALIGN(attrlen));
	307
	308	return start;
	309	}
	310
bfa83a9e TG	311	/**
	312	* nla_reserve - reserve room for attribute on the skb
	313	* @skb: socket buffer to reserve room on
	314	* @attrtype: attribute type
	315	* @attrlen: length of attribute payload
	316	*
	317	* Adds a netlink attribute header to a socket buffer and reserves
	318	* room for the payload but does not copy it.
	319	*
	320	* Returns NULL if the tailroom of the skb is insufficient to store
	321	* the attribute header and payload.
	322	*/
	323	struct nlattr nla_reserve(struct sk_buff skb, int attrtype, int attrlen)
	324	{
	325	if (unlikely(skb_tailroom(skb) < nla_total_size(attrlen)))
	326	return NULL;
	327
	328	return __nla_reserve(skb, attrtype, attrlen);
	329	}
	330
fe4944e5 TG	331	/**
	332	* nla_reserve - reserve room for attribute without header
	333	* @skb: socket buffer to reserve room on
	334	* @len: length of attribute payload
	335	*
	336	* Reserves room for attribute payload without a header.
	337	*
	338	* Returns NULL if the tailroom of the skb is insufficient to store
	339	* the attribute payload.
	340	*/
	341	void nla_reserve_nohdr(struct sk_buff skb, int attrlen)
	342	{
	343	if (unlikely(skb_tailroom(skb) < NLA_ALIGN(attrlen)))
	344	return NULL;
	345
	346	return __nla_reserve_nohdr(skb, attrlen);
	347	}
	348
bfa83a9e TG	349	/**
	350	* __nla_put - Add a netlink attribute to a socket buffer
	351	* @skb: socket buffer to add attribute to
	352	* @attrtype: attribute type
	353	* @attrlen: length of attribute payload
	354	* @data: head of attribute payload
	355	*
	356	* The caller is responsible to ensure that the skb provides enough
	357	* tailroom for the attribute header and payload.
	358	*/
	359	void __nla_put(struct sk_buff *skb, int attrtype, int attrlen,
	360	const void *data)
	361	{
	362	struct nlattr *nla;
	363
	364	nla = __nla_reserve(skb, attrtype, attrlen);
	365	memcpy(nla_data(nla), data, attrlen);
	366	}
	367
fe4944e5 TG	368	/**
	369	* __nla_put_nohdr - Add a netlink attribute without header
	370	* @skb: socket buffer to add attribute to
	371	* @attrlen: length of attribute payload
	372	* @data: head of attribute payload
	373	*
	374	* The caller is responsible to ensure that the skb provides enough
	375	* tailroom for the attribute payload.
	376	*/
	377	void __nla_put_nohdr(struct sk_buff skb, int attrlen, const void data)
	378	{
	379	void *start;
	380
	381	start = __nla_reserve_nohdr(skb, attrlen);
	382	memcpy(start, data, attrlen);
	383	}
bfa83a9e TG	384
	385	/**
	386	* nla_put - Add a netlink attribute to a socket buffer
	387	* @skb: socket buffer to add attribute to
	388	* @attrtype: attribute type
	389	* @attrlen: length of attribute payload
	390	* @data: head of attribute payload
	391	*
	392	* Returns -1 if the tailroom of the skb is insufficient to store
	393	* the attribute header and payload.
	394	*/
	395	int nla_put(struct sk_buff skb, int attrtype, int attrlen, const void data)
	396	{
	397	if (unlikely(skb_tailroom(skb) < nla_total_size(attrlen)))
	398	return -1;
	399
	400	__nla_put(skb, attrtype, attrlen, data);
	401	return 0;
	402	}
	403
fe4944e5 TG	404	/**
	405	* nla_put_nohdr - Add a netlink attribute without header
	406	* @skb: socket buffer to add attribute to
	407	* @attrlen: length of attribute payload
	408	* @data: head of attribute payload
	409	*
	410	* Returns -1 if the tailroom of the skb is insufficient to store
	411	* the attribute payload.
	412	*/
	413	int nla_put_nohdr(struct sk_buff skb, int attrlen, const void data)
	414	{
	415	if (unlikely(skb_tailroom(skb) < NLA_ALIGN(attrlen)))
	416	return -1;
	417
	418	__nla_put_nohdr(skb, attrlen, data);
	419	return 0;
	420	}
bfa83a9e TG	421
	422	EXPORT_SYMBOL(nla_validate);
	423	EXPORT_SYMBOL(nla_parse);
	424	EXPORT_SYMBOL(nla_find);
	425	EXPORT_SYMBOL(nla_strlcpy);
	426	EXPORT_SYMBOL(__nla_reserve);
fe4944e5	427	EXPORT_SYMBOL(__nla_reserve_nohdr);
bfa83a9e	428	EXPORT_SYMBOL(nla_reserve);
fe4944e5	429	EXPORT_SYMBOL(nla_reserve_nohdr);
bfa83a9e	430	EXPORT_SYMBOL(__nla_put);
fe4944e5	431	EXPORT_SYMBOL(__nla_put_nohdr);
bfa83a9e	432	EXPORT_SYMBOL(nla_put);
fe4944e5	433	EXPORT_SYMBOL(nla_put_nohdr);
bfa83a9e TG	434	EXPORT_SYMBOL(nla_memcpy);
	435	EXPORT_SYMBOL(nla_memcmp);
	436	EXPORT_SYMBOL(nla_strcmp);