[mirror_ubuntu-zesty-kernel.git] / net / core / utils.c

/*
 *	Generic address resultion entity
 *
 *	Authors:
 *	net_random Alan Cox
 *	net_ratelimit Andi Kleen
 *	in{4,6}_pton YOSHIFUJI Hideaki, Copyright (C)2006 USAGI/WIDE Project
 *
 *	Created by Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
 *
 *	This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 */

#include <linux/module.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/inet.h>
#include <linux/mm.h>
#include <linux/net.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/percpu.h>
#include <linux/init.h>
#include <linux/ratelimit.h>

#include <net/sock.h>
#include <net/net_ratelimit.h>

#include <asm/byteorder.h>
#include <asm/uaccess.h>

int net_msg_warn __read_mostly = 1;
EXPORT_SYMBOL(net_msg_warn);

DEFINE_RATELIMIT_STATE(net_ratelimit_state, 5 * HZ, 10);
/*
 * All net warning printk()s should be guarded by this function.
 */
int net_ratelimit(void)
{
	return __ratelimit(&net_ratelimit_state);
}
EXPORT_SYMBOL(net_ratelimit);

/*
 * Convert an ASCII string to binary IP.
 * This is outside of net/ipv4/ because various code that uses IP addresses
 * is otherwise not dependent on the TCP/IP stack.
 */

__be32 in_aton(const char *str)
{
	unsigned long l;
	unsigned int val;
	int i;

	l = 0;
	for (i = 0; i < 4; i++)	{
		l <<= 8;
		if (*str != '\0') {
			val = 0;
			while (*str != '\0' && *str != '.' && *str != '\n') {
				val *= 10;
				val += *str - '0';
				str++;
			}
			l |= val;
			if (*str != '\0')
				str++;
		}
	}
	return htonl(l);
}
EXPORT_SYMBOL(in_aton);

#define IN6PTON_XDIGIT		0x00010000
#define IN6PTON_DIGIT		0x00020000
#define IN6PTON_COLON_MASK	0x00700000
#define IN6PTON_COLON_1		0x00100000	/* single : requested */
#define IN6PTON_COLON_2		0x00200000	/* second : requested */
#define IN6PTON_COLON_1_2	0x00400000	/* :: requested */
#define IN6PTON_DOT		0x00800000	/* . */
#define IN6PTON_DELIM		0x10000000
#define IN6PTON_NULL		0x20000000	/* first/tail */
#define IN6PTON_UNKNOWN		0x40000000

static inline int xdigit2bin(char c, int delim)
{
	int val;

	if (c == delim || c == '\0')
		return IN6PTON_DELIM;
	if (c == ':')
		return IN6PTON_COLON_MASK;
	if (c == '.')
		return IN6PTON_DOT;

	val = hex_to_bin(c);
	if (val >= 0)
		return val | IN6PTON_XDIGIT | (val < 10 ? IN6PTON_DIGIT : 0);

	if (delim == -1)
		return IN6PTON_DELIM;
	return IN6PTON_UNKNOWN;
}

int in4_pton(const char *src, int srclen,
	     u8 *dst,
	     int delim, const char **end)
{
	const char *s;
	u8 *d;
	u8 dbuf[4];
	int ret = 0;
	int i;
	int w = 0;

	if (srclen < 0)
		srclen = strlen(src);
	s = src;
	d = dbuf;
	i = 0;
	while(1) {
		int c;
		c = xdigit2bin(srclen > 0 ? *s : '\0', delim);
		if (!(c & (IN6PTON_DIGIT | IN6PTON_DOT | IN6PTON_DELIM | IN6PTON_COLON_MASK))) {
			goto out;
		}
		if (c & (IN6PTON_DOT | IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
			if (w == 0)
				goto out;
			*d++ = w & 0xff;
			w = 0;
			i++;
			if (c & (IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
				if (i != 4)
					goto out;
				break;
			}
			goto cont;
		}
		w = (w * 10) + c;
		if ((w & 0xffff) > 255) {
			goto out;
		}
cont:
		if (i >= 4)
			goto out;
		s++;
		srclen--;
	}
	ret = 1;
	memcpy(dst, dbuf, sizeof(dbuf));
out:
	if (end)
		*end = s;
	return ret;
}
EXPORT_SYMBOL(in4_pton);

/**
 * in6_pton - convert an IPv6 address from literal to binary representation
 * @src: the start of the IPv6 address string
 * @srclen: the length of the string, -1 means strlen(src)
 * @dst: the binary (u8[16] array) representation of the IPv6 address
 * @delim: the delimiter of the IPv6 address in @src, -1 means no delimiter
 * @end: A pointer to the end of the parsed string will be placed here
 *
 * Return one on success, return zero when any error occurs
 * and @end will point to the end of the parsed string.
 *
 */
int in6_pton(const char *src, int srclen,
	     u8 *dst,
	     int delim, const char **end)
{
	const char *s, *tok = NULL;
	u8 *d, *dc = NULL;
	u8 dbuf[16];
	int ret = 0;
	int i;
	int state = IN6PTON_COLON_1_2 | IN6PTON_XDIGIT | IN6PTON_NULL;
	int w = 0;

	memset(dbuf, 0, sizeof(dbuf));

	s = src;
	d = dbuf;
	if (srclen < 0)
		srclen = strlen(src);

	while (1) {
		int c;

		c = xdigit2bin(srclen > 0 ? *s : '\0', delim);
		if (!(c & state))
			goto out;
		if (c & (IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
			/* process one 16-bit word */
			if (!(state & IN6PTON_NULL)) {
				*d++ = (w >> 8) & 0xff;
				*d++ = w & 0xff;
			}
			w = 0;
			if (c & IN6PTON_DELIM) {
				/* We've processed last word */
				break;
			}
			/*
			 * COLON_1 => XDIGIT
			 * COLON_2 => XDIGIT|DELIM
			 * COLON_1_2 => COLON_2
			 */
			switch (state & IN6PTON_COLON_MASK) {
			case IN6PTON_COLON_2:
				dc = d;
				state = IN6PTON_XDIGIT | IN6PTON_DELIM;
				if (dc - dbuf >= sizeof(dbuf))
					state |= IN6PTON_NULL;
				break;
			case IN6PTON_COLON_1|IN6PTON_COLON_1_2:
				state = IN6PTON_XDIGIT | IN6PTON_COLON_2;
				break;
			case IN6PTON_COLON_1:
				state = IN6PTON_XDIGIT;
				break;
			case IN6PTON_COLON_1_2:
				state = IN6PTON_COLON_2;
				break;
			default:
				state = 0;
			}
			tok = s + 1;
			goto cont;
		}

		if (c & IN6PTON_DOT) {
			ret = in4_pton(tok ? tok : s, srclen + (int)(s - tok), d, delim, &s);
			if (ret > 0) {
				d += 4;
				break;
			}
			goto out;
		}

		w = (w << 4) | (0xff & c);
		state = IN6PTON_COLON_1 | IN6PTON_DELIM;
		if (!(w & 0xf000)) {
			state |= IN6PTON_XDIGIT;
		}
		if (!dc && d + 2 < dbuf + sizeof(dbuf)) {
			state |= IN6PTON_COLON_1_2;
			state &= ~IN6PTON_DELIM;
		}
		if (d + 2 >= dbuf + sizeof(dbuf)) {
			state &= ~(IN6PTON_COLON_1|IN6PTON_COLON_1_2);
		}
cont:
		if ((dc && d + 4 < dbuf + sizeof(dbuf)) ||
		    d + 4 == dbuf + sizeof(dbuf)) {
			state |= IN6PTON_DOT;
		}
		if (d >= dbuf + sizeof(dbuf)) {
			state &= ~(IN6PTON_XDIGIT|IN6PTON_COLON_MASK);
		}
		s++;
		srclen--;
	}

	i = 15; d--;

	if (dc) {
		while(d >= dc)
			dst[i--] = *d--;
		while(i >= dc - dbuf)
			dst[i--] = 0;
		while(i >= 0)
			dst[i--] = *d--;
	} else
		memcpy(dst, dbuf, sizeof(dbuf));

	ret = 1;
out:
	if (end)
		*end = s;
	return ret;
}
EXPORT_SYMBOL(in6_pton);

void inet_proto_csum_replace4(__sum16 *sum, struct sk_buff *skb,
			      __be32 from, __be32 to, int pseudohdr)
{
	__be32 diff[] = { ~from, to };
	if (skb->ip_summed != CHECKSUM_PARTIAL) {
		*sum = csum_fold(csum_partial(diff, sizeof(diff),
				~csum_unfold(*sum)));
		if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
			skb->csum = ~csum_partial(diff, sizeof(diff),
						~skb->csum);
	} else if (pseudohdr)
		*sum = ~csum_fold(csum_partial(diff, sizeof(diff),
				csum_unfold(*sum)));
}
EXPORT_SYMBOL(inet_proto_csum_replace4);

void inet_proto_csum_replace16(__sum16 *sum, struct sk_buff *skb,
			       const __be32 *from, const __be32 *to,
			       int pseudohdr)
{
	__be32 diff[] = {
		~from[0], ~from[1], ~from[2], ~from[3],
		to[0], to[1], to[2], to[3],
	};
	if (skb->ip_summed != CHECKSUM_PARTIAL) {
		*sum = csum_fold(csum_partial(diff, sizeof(diff),
				 ~csum_unfold(*sum)));
		if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
			skb->csum = ~csum_partial(diff, sizeof(diff),
						  ~skb->csum);
	} else if (pseudohdr)
		*sum = ~csum_fold(csum_partial(diff, sizeof(diff),
				  csum_unfold(*sum)));
}
EXPORT_SYMBOL(inet_proto_csum_replace16);

int mac_pton(const char *s, u8 *mac)
{
	int i;

	/* XX:XX:XX:XX:XX:XX */
	if (strlen(s) < 3 * ETH_ALEN - 1)
		return 0;

	/* Don't dirty result unless string is valid MAC. */
	for (i = 0; i < ETH_ALEN; i++) {
		if (!strchr("0123456789abcdefABCDEF", s[i * 3]))
			return 0;
		if (!strchr("0123456789abcdefABCDEF", s[i * 3 + 1]))
			return 0;
		if (i != ETH_ALEN - 1 && s[i * 3 + 2] != ':')
			return 0;
	}
	for (i = 0; i < ETH_ALEN; i++) {
		mac[i] = (hex_to_bin(s[i * 3]) << 4) | hex_to_bin(s[i * 3 + 1]);
	}
	return 1;
}
EXPORT_SYMBOL(mac_pton);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Generic address resultion entity
	3	*
	4	* Authors:
	5	* net_random Alan Cox
75b31c33	6	* net_ratelimit Andi Kleen
1aaec67f	7	* in{4,6}_pton YOSHIFUJI Hideaki, Copyright (C)2006 USAGI/WIDE Project
1da177e4 LT	8	*
	9	* Created by Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
	10	*
	11	* This program is free software; you can redistribute it and/or
	12	* modify it under the terms of the GNU General Public License
	13	* as published by the Free Software Foundation; either version
	14	* 2 of the License, or (at your option) any later version.
	15	*/
	16
	17	#include <linux/module.h>
	18	#include <linux/jiffies.h>
	19	#include <linux/kernel.h>
20380731	20	#include <linux/inet.h>
1da177e4	21	#include <linux/mm.h>
20380731	22	#include <linux/net.h>
1da177e4 LT	23	#include <linux/string.h>
1da177e4 LT	24	#include <linux/types.h>
1da177e4 LT	25	#include <linux/percpu.h>
1da177e4 LT	26	#include <linux/init.h>
3fff4c42 IM	27	#include <linux/ratelimit.h>
3fff4c42 IM	28
14ae8566	29	#include <net/sock.h>
c5c177b4	30	#include <net/net_ratelimit.h>
1da177e4	31
5e43db77	32	#include <asm/byteorder.h>
1da177e4 LT	33	#include <asm/uaccess.h>
1da177e4 LT	34
6dea649a	35	int net_msg_warn __read_mostly = 1;
a2a316fd	36	EXPORT_SYMBOL(net_msg_warn);
1da177e4	37
717115e1	38	DEFINE_RATELIMIT_STATE(net_ratelimit_state, 5 * HZ, 10);
4ec93edb	39	/*
1da177e4	40	* All net warning printk()s should be guarded by this function.
4ec93edb	41	*/
1da177e4 LT	42	int net_ratelimit(void)
1da177e4 LT	43	{
717115e1	44	return __ratelimit(&net_ratelimit_state);
1da177e4	45	}
1da177e4	46	EXPORT_SYMBOL(net_ratelimit);
5e43db77 MM	47
	48	/*
	49	* Convert an ASCII string to binary IP.
	50	* This is outside of net/ipv4/ because various code that uses IP addresses
	51	* is otherwise not dependent on the TCP/IP stack.
	52	*/
	53
a2167dc6	54	__be32 in_aton(const char *str)
5e43db77 MM	55	{
	56	unsigned long l;
	57	unsigned int val;
	58	int i;
	59
	60	l = 0;
46ba5b23	61	for (i = 0; i < 4; i++) {
5e43db77	62	l <<= 8;
46ba5b23	63	if (*str != '\0') {
5e43db77	64	val = 0;
46ba5b23	65	while (str != '\0' && str != '.' && *str != '\n') {
5e43db77 MM	66	val *= 10;
	67	val += *str - '0';
	68	str++;
	69	}
	70	l \|= val;
	71	if (*str != '\0')
	72	str++;
	73	}
	74	}
a02cec21	75	return htonl(l);
5e43db77	76	}
5e43db77	77	EXPORT_SYMBOL(in_aton);
1aaec67f YH	78
	79	#define IN6PTON_XDIGIT 0x00010000
	80	#define IN6PTON_DIGIT 0x00020000
	81	#define IN6PTON_COLON_MASK 0x00700000
	82	#define IN6PTON_COLON_1 0x00100000 /* single : requested */
	83	#define IN6PTON_COLON_2 0x00200000 /* second : requested */
	84	#define IN6PTON_COLON_1_2 0x00400000 /* :: requested */
	85	#define IN6PTON_DOT 0x00800000 /* . */
	86	#define IN6PTON_DELIM 0x10000000
	87	#define IN6PTON_NULL 0x20000000 /* first/tail */
	88	#define IN6PTON_UNKNOWN 0x40000000
	89
9a7c9337	90	static inline int xdigit2bin(char c, int delim)
1aaec67f	91	{
82fd5b5d AS	92	int val;
82fd5b5d AS	93
1aaec67f YH	94	if (c == delim \|\| c == '\0')
	95	return IN6PTON_DELIM;
	96	if (c == ':')
	97	return IN6PTON_COLON_MASK;
	98	if (c == '.')
	99	return IN6PTON_DOT;
82fd5b5d AS	100
	101	val = hex_to_bin(c);
	102	if (val >= 0)
	103	return val \| IN6PTON_XDIGIT \| (val < 10 ? IN6PTON_DIGIT : 0);
	104
9a7c9337 PM	105	if (delim == -1)
9a7c9337 PM	106	return IN6PTON_DELIM;
1aaec67f YH	107	return IN6PTON_UNKNOWN;
	108	}
	109
	110	int in4_pton(const char *src, int srclen,
	111	u8 *dst,
9a7c9337	112	int delim, const char **end)
1aaec67f YH	113	{
	114	const char *s;
	115	u8 *d;
	116	u8 dbuf[4];
	117	int ret = 0;
	118	int i;
	119	int w = 0;
	120
	121	if (srclen < 0)
	122	srclen = strlen(src);
	123	s = src;
	124	d = dbuf;
	125	i = 0;
	126	while(1) {
	127	int c;
	128	c = xdigit2bin(srclen > 0 ? *s : '\0', delim);
83f03fa5	129	if (!(c & (IN6PTON_DIGIT \| IN6PTON_DOT \| IN6PTON_DELIM \| IN6PTON_COLON_MASK))) {
1aaec67f YH	130	goto out;
1aaec67f YH	131	}
83f03fa5	132	if (c & (IN6PTON_DOT \| IN6PTON_DELIM \| IN6PTON_COLON_MASK)) {
1aaec67f YH	133	if (w == 0)
	134	goto out;
	135	*d++ = w & 0xff;
	136	w = 0;
	137	i++;
83f03fa5	138	if (c & (IN6PTON_DELIM \| IN6PTON_COLON_MASK)) {
1aaec67f YH	139	if (i != 4)
	140	goto out;
	141	break;
	142	}
	143	goto cont;
	144	}
	145	w = (w * 10) + c;
	146	if ((w & 0xffff) > 255) {
	147	goto out;
	148	}
	149	cont:
	150	if (i >= 4)
	151	goto out;
	152	s++;
	153	srclen--;
	154	}
	155	ret = 1;
	156	memcpy(dst, dbuf, sizeof(dbuf));
	157	out:
	158	if (end)
	159	*end = s;
	160	return ret;
	161	}
1aaec67f YH	162	EXPORT_SYMBOL(in4_pton);
1aaec67f YH	163
28194fcd AW	164	/**
	165	* in6_pton - convert an IPv6 address from literal to binary representation
	166	* @src: the start of the IPv6 address string
	167	* @srclen: the length of the string, -1 means strlen(src)
	168	* @dst: the binary (u8[16] array) representation of the IPv6 address
	169	* @delim: the delimiter of the IPv6 address in @src, -1 means no delimiter
	170	* @end: A pointer to the end of the parsed string will be placed here
	171	*
	172	* Return one on success, return zero when any error occurs
	173	* and @end will point to the end of the parsed string.
	174	*
	175	*/
1aaec67f YH	176	int in6_pton(const char *src, int srclen,
1aaec67f YH	177	u8 *dst,
9a7c9337	178	int delim, const char **end)
1aaec67f YH	179	{
	180	const char s, tok = NULL;
	181	u8 d, dc = NULL;
	182	u8 dbuf[16];
	183	int ret = 0;
	184	int i;
	185	int state = IN6PTON_COLON_1_2 \| IN6PTON_XDIGIT \| IN6PTON_NULL;
	186	int w = 0;
	187
	188	memset(dbuf, 0, sizeof(dbuf));
	189
	190	s = src;
	191	d = dbuf;
	192	if (srclen < 0)
	193	srclen = strlen(src);
	194
1aaec67f YH	195	while (1) {
	196	int c;
	197
	198	c = xdigit2bin(srclen > 0 ? *s : '\0', delim);
	199	if (!(c & state))
	200	goto out;
	201	if (c & (IN6PTON_DELIM \| IN6PTON_COLON_MASK)) {
	202	/* process one 16-bit word */
	203	if (!(state & IN6PTON_NULL)) {
	204	*d++ = (w >> 8) & 0xff;
	205	*d++ = w & 0xff;
	206	}
	207	w = 0;
	208	if (c & IN6PTON_DELIM) {
	209	/* We've processed last word */
	210	break;
	211	}
	212	/*
	213	* COLON_1 => XDIGIT
	214	* COLON_2 => XDIGIT\|DELIM
	215	* COLON_1_2 => COLON_2
	216	*/
	217	switch (state & IN6PTON_COLON_MASK) {
	218	case IN6PTON_COLON_2:
	219	dc = d;
	220	state = IN6PTON_XDIGIT \| IN6PTON_DELIM;
	221	if (dc - dbuf >= sizeof(dbuf))
	222	state \|= IN6PTON_NULL;
	223	break;
	224	case IN6PTON_COLON_1\|IN6PTON_COLON_1_2:
	225	state = IN6PTON_XDIGIT \| IN6PTON_COLON_2;
	226	break;
	227	case IN6PTON_COLON_1:
	228	state = IN6PTON_XDIGIT;
	229	break;
	230	case IN6PTON_COLON_1_2:
	231	state = IN6PTON_COLON_2;
	232	break;
	233	default:
	234	state = 0;
	235	}
	236	tok = s + 1;
	237	goto cont;
	238	}
	239
	240	if (c & IN6PTON_DOT) {
	241	ret = in4_pton(tok ? tok : s, srclen + (int)(s - tok), d, delim, &s);
	242	if (ret > 0) {
	243	d += 4;
	244	break;
	245	}
	246	goto out;
	247	}
	248
	249	w = (w << 4) \| (0xff & c);
	250	state = IN6PTON_COLON_1 \| IN6PTON_DELIM;
	251	if (!(w & 0xf000)) {
	252	state \|= IN6PTON_XDIGIT;
	253	}
	254	if (!dc && d + 2 < dbuf + sizeof(dbuf)) {
	255	state \|= IN6PTON_COLON_1_2;
	256	state &= ~IN6PTON_DELIM;
	257	}
	258	if (d + 2 >= dbuf + sizeof(dbuf)) {
259	state &= ~(IN6PTON_COLON_1\|IN6PTON_COLON_1_2);
260	}
261	cont:
262	if ((dc && d + 4 < dbuf + sizeof(dbuf)) \|\|
263	d + 4 == dbuf + sizeof(dbuf)) {
264	state \|= IN6PTON_DOT;
265	}
266	if (d >= dbuf + sizeof(dbuf)) {
267	state &= ~(IN6PTON_XDIGIT\|IN6PTON_COLON_MASK);
268	}
269	s++;
270	srclen--;
271	}
272
273	i = 15; d--;
274
275	if (dc) {
276	while(d >= dc)
277	dst[i--] = *d--;
278	while(i >= dc - dbuf)
279	dst[i--] = 0;
280	while(i >= 0)
281	dst[i--] = *d--;
282	} else
283	memcpy(dst, dbuf, sizeof(dbuf));
284
285	ret = 1;
286	out:
287	if (end)
288	*end = s;
289	return ret;
290	}
1aaec67f	291	EXPORT_SYMBOL(in6_pton);
a99a00cf PM	292
	293	void inet_proto_csum_replace4(__sum16 sum, struct sk_buff skb,
	294	__be32 from, __be32 to, int pseudohdr)
	295	{
	296	__be32 diff[] = { ~from, to };
	297	if (skb->ip_summed != CHECKSUM_PARTIAL) {
	298	*sum = csum_fold(csum_partial(diff, sizeof(diff),
	299	~csum_unfold(*sum)));
	300	if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
	301	skb->csum = ~csum_partial(diff, sizeof(diff),
	302	~skb->csum);
	303	} else if (pseudohdr)
	304	*sum = ~csum_fold(csum_partial(diff, sizeof(diff),
	305	csum_unfold(*sum)));
	306	}
	307	EXPORT_SYMBOL(inet_proto_csum_replace4);
4940fc88	308
2cf545e8 PM	309	void inet_proto_csum_replace16(__sum16 sum, struct sk_buff skb,
	310	const __be32 from, const __be32 to,
	311	int pseudohdr)
	312	{
	313	__be32 diff[] = {
	314	~from[0], ~from[1], ~from[2], ~from[3],
	315	to[0], to[1], to[2], to[3],
	316	};
	317	if (skb->ip_summed != CHECKSUM_PARTIAL) {
	318	*sum = csum_fold(csum_partial(diff, sizeof(diff),
	319	~csum_unfold(*sum)));
	320	if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
	321	skb->csum = ~csum_partial(diff, sizeof(diff),
	322	~skb->csum);
	323	} else if (pseudohdr)
	324	*sum = ~csum_fold(csum_partial(diff, sizeof(diff),
	325	csum_unfold(*sum)));
	326	}
	327	EXPORT_SYMBOL(inet_proto_csum_replace16);
	328
4940fc88 AD	329	int mac_pton(const char s, u8 mac)
	330	{
	331	int i;
	332
	333	/* XX:XX:XX:XX:XX:XX */
	334	if (strlen(s) < 3 * ETH_ALEN - 1)
	335	return 0;
	336
	337	/* Don't dirty result unless string is valid MAC. */
	338	for (i = 0; i < ETH_ALEN; i++) {
	339	if (!strchr("0123456789abcdefABCDEF", s[i * 3]))
	340	return 0;
	341	if (!strchr("0123456789abcdefABCDEF", s[i * 3 + 1]))
	342	return 0;
	343	if (i != ETH_ALEN - 1 && s[i * 3 + 2] != ':')
	344	return 0;
	345	}
	346	for (i = 0; i < ETH_ALEN; i++) {
	347	mac[i] = (hex_to_bin(s[i * 3]) << 4) \| hex_to_bin(s[i * 3 + 1]);
	348	}
	349	return 1;
	350	}
	351	EXPORT_SYMBOL(mac_pton);