[linux-2.6-block.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/ctype.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;
}

/**
 * in4_pton - convert an IPv4 address from literal to binary representation
 * @src: the start of the IPv4 address string
 * @srclen: the length of the string, -1 means strlen(src)
 * @dst: the binary (u8[4] array) representation of the IPv4 address
 * @delim: the delimiter of the IPv4 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 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);
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>
5a048e3b	20	#include <linux/ctype.h>
20380731	21	#include <linux/inet.h>
1da177e4	22	#include <linux/mm.h>
20380731	23	#include <linux/net.h>
1da177e4 LT	24	#include <linux/string.h>
1da177e4 LT	25	#include <linux/types.h>
1da177e4 LT	26	#include <linux/percpu.h>
1da177e4 LT	27	#include <linux/init.h>
3fff4c42 IM	28	#include <linux/ratelimit.h>
3fff4c42 IM	29
14ae8566	30	#include <net/sock.h>
c5c177b4	31	#include <net/net_ratelimit.h>
1da177e4	32
5e43db77	33	#include <asm/byteorder.h>
1da177e4 LT	34	#include <asm/uaccess.h>
1da177e4 LT	35
6dea649a	36	int net_msg_warn __read_mostly = 1;
a2a316fd	37	EXPORT_SYMBOL(net_msg_warn);
1da177e4	38
717115e1	39	DEFINE_RATELIMIT_STATE(net_ratelimit_state, 5 * HZ, 10);
4ec93edb	40	/*
1da177e4	41	* All net warning printk()s should be guarded by this function.
4ec93edb	42	*/
1da177e4 LT	43	int net_ratelimit(void)
1da177e4 LT	44	{
717115e1	45	return __ratelimit(&net_ratelimit_state);
1da177e4	46	}
1da177e4	47	EXPORT_SYMBOL(net_ratelimit);
5e43db77 MM	48
	49	/*
	50	* Convert an ASCII string to binary IP.
	51	* This is outside of net/ipv4/ because various code that uses IP addresses
	52	* is otherwise not dependent on the TCP/IP stack.
	53	*/
	54
a2167dc6	55	__be32 in_aton(const char *str)
5e43db77 MM	56	{
	57	unsigned long l;
	58	unsigned int val;
	59	int i;
	60
	61	l = 0;
46ba5b23	62	for (i = 0; i < 4; i++) {
5e43db77	63	l <<= 8;
46ba5b23	64	if (*str != '\0') {
5e43db77	65	val = 0;
46ba5b23	66	while (str != '\0' && str != '.' && *str != '\n') {
5e43db77 MM	67	val *= 10;
	68	val += *str - '0';
	69	str++;
	70	}
	71	l \|= val;
	72	if (*str != '\0')
	73	str++;
	74	}
	75	}
a02cec21	76	return htonl(l);
5e43db77	77	}
5e43db77	78	EXPORT_SYMBOL(in_aton);
1aaec67f YH	79
	80	#define IN6PTON_XDIGIT 0x00010000
	81	#define IN6PTON_DIGIT 0x00020000
	82	#define IN6PTON_COLON_MASK 0x00700000
	83	#define IN6PTON_COLON_1 0x00100000 /* single : requested */
	84	#define IN6PTON_COLON_2 0x00200000 /* second : requested */
	85	#define IN6PTON_COLON_1_2 0x00400000 /* :: requested */
	86	#define IN6PTON_DOT 0x00800000 /* . */
	87	#define IN6PTON_DELIM 0x10000000
	88	#define IN6PTON_NULL 0x20000000 /* first/tail */
	89	#define IN6PTON_UNKNOWN 0x40000000
	90
9a7c9337	91	static inline int xdigit2bin(char c, int delim)
1aaec67f	92	{
82fd5b5d AS	93	int val;
82fd5b5d AS	94
1aaec67f YH	95	if (c == delim \|\| c == '\0')
	96	return IN6PTON_DELIM;
	97	if (c == ':')
	98	return IN6PTON_COLON_MASK;
	99	if (c == '.')
	100	return IN6PTON_DOT;
82fd5b5d AS	101
	102	val = hex_to_bin(c);
	103	if (val >= 0)
	104	return val \| IN6PTON_XDIGIT \| (val < 10 ? IN6PTON_DIGIT : 0);
	105
9a7c9337 PM	106	if (delim == -1)
9a7c9337 PM	107	return IN6PTON_DELIM;
1aaec67f YH	108	return IN6PTON_UNKNOWN;
	109	}
	110
93ac0ef0 AW	111	/**
	112	* in4_pton - convert an IPv4 address from literal to binary representation
	113	* @src: the start of the IPv4 address string
	114	* @srclen: the length of the string, -1 means strlen(src)
	115	* @dst: the binary (u8[4] array) representation of the IPv4 address
	116	* @delim: the delimiter of the IPv4 address in @src, -1 means no delimiter
	117	* @end: A pointer to the end of the parsed string will be placed here
	118	*
	119	* Return one on success, return zero when any error occurs
	120	* and @end will point to the end of the parsed string.
	121	*
	122	*/
1aaec67f YH	123	int in4_pton(const char *src, int srclen,
1aaec67f YH	124	u8 *dst,
9a7c9337	125	int delim, const char **end)
1aaec67f YH	126	{
	127	const char *s;
	128	u8 *d;
	129	u8 dbuf[4];
	130	int ret = 0;
	131	int i;
	132	int w = 0;
	133
	134	if (srclen < 0)
	135	srclen = strlen(src);
	136	s = src;
	137	d = dbuf;
	138	i = 0;
	139	while(1) {
	140	int c;
	141	c = xdigit2bin(srclen > 0 ? *s : '\0', delim);
83f03fa5	142	if (!(c & (IN6PTON_DIGIT \| IN6PTON_DOT \| IN6PTON_DELIM \| IN6PTON_COLON_MASK))) {
1aaec67f YH	143	goto out;
1aaec67f YH	144	}
83f03fa5	145	if (c & (IN6PTON_DOT \| IN6PTON_DELIM \| IN6PTON_COLON_MASK)) {
1aaec67f YH	146	if (w == 0)
	147	goto out;
	148	*d++ = w & 0xff;
	149	w = 0;
	150	i++;
83f03fa5	151	if (c & (IN6PTON_DELIM \| IN6PTON_COLON_MASK)) {
1aaec67f YH	152	if (i != 4)
	153	goto out;
	154	break;
	155	}
	156	goto cont;
	157	}
	158	w = (w * 10) + c;
	159	if ((w & 0xffff) > 255) {
	160	goto out;
	161	}
	162	cont:
	163	if (i >= 4)
	164	goto out;
	165	s++;
	166	srclen--;
	167	}
	168	ret = 1;
	169	memcpy(dst, dbuf, sizeof(dbuf));
	170	out:
	171	if (end)
	172	*end = s;
	173	return ret;
	174	}
1aaec67f YH	175	EXPORT_SYMBOL(in4_pton);
1aaec67f YH	176
28194fcd AW	177	/**
	178	* in6_pton - convert an IPv6 address from literal to binary representation
	179	* @src: the start of the IPv6 address string
	180	* @srclen: the length of the string, -1 means strlen(src)
	181	* @dst: the binary (u8[16] array) representation of the IPv6 address
	182	* @delim: the delimiter of the IPv6 address in @src, -1 means no delimiter
	183	* @end: A pointer to the end of the parsed string will be placed here
	184	*
	185	* Return one on success, return zero when any error occurs
	186	* and @end will point to the end of the parsed string.
	187	*
	188	*/
1aaec67f YH	189	int in6_pton(const char *src, int srclen,
1aaec67f YH	190	u8 *dst,
9a7c9337	191	int delim, const char **end)
1aaec67f YH	192	{
	193	const char s, tok = NULL;
	194	u8 d, dc = NULL;
	195	u8 dbuf[16];
	196	int ret = 0;
	197	int i;
	198	int state = IN6PTON_COLON_1_2 \| IN6PTON_XDIGIT \| IN6PTON_NULL;
	199	int w = 0;
	200
	201	memset(dbuf, 0, sizeof(dbuf));
	202
	203	s = src;
	204	d = dbuf;
	205	if (srclen < 0)
	206	srclen = strlen(src);
	207
1aaec67f YH	208	while (1) {
	209	int c;
	210
	211	c = xdigit2bin(srclen > 0 ? *s : '\0', delim);
	212	if (!(c & state))
	213	goto out;
	214	if (c & (IN6PTON_DELIM \| IN6PTON_COLON_MASK)) {
	215	/* process one 16-bit word */
	216	if (!(state & IN6PTON_NULL)) {
	217	*d++ = (w >> 8) & 0xff;
	218	*d++ = w & 0xff;
	219	}
	220	w = 0;
	221	if (c & IN6PTON_DELIM) {
	222	/* We've processed last word */
	223	break;
	224	}
	225	/*
	226	* COLON_1 => XDIGIT
	227	* COLON_2 => XDIGIT\|DELIM
	228	* COLON_1_2 => COLON_2
	229	*/
	230	switch (state & IN6PTON_COLON_MASK) {
	231	case IN6PTON_COLON_2:
	232	dc = d;
	233	state = IN6PTON_XDIGIT \| IN6PTON_DELIM;
	234	if (dc - dbuf >= sizeof(dbuf))
	235	state \|= IN6PTON_NULL;
	236	break;
	237	case IN6PTON_COLON_1\|IN6PTON_COLON_1_2:
	238	state = IN6PTON_XDIGIT \| IN6PTON_COLON_2;
	239	break;
	240	case IN6PTON_COLON_1:
	241	state = IN6PTON_XDIGIT;
	242	break;
	243	case IN6PTON_COLON_1_2:
	244	state = IN6PTON_COLON_2;
	245	break;
	246	default:
	247	state = 0;
	248	}
	249	tok = s + 1;
	250	goto cont;
	251	}
	252
	253	if (c & IN6PTON_DOT) {
	254	ret = in4_pton(tok ? tok : s, srclen + (int)(s - tok), d, delim, &s);
	255	if (ret > 0) {
	256	d += 4;
	257	break;
	258	}
	259	goto out;
	260	}
	261
	262	w = (w << 4) \| (0xff & c);
	263	state = IN6PTON_COLON_1 \| IN6PTON_DELIM;
	264	if (!(w & 0xf000)) {
	265	state \|= IN6PTON_XDIGIT;
	266	}
	267	if (!dc && d + 2 < dbuf + sizeof(dbuf)) {
	268	state \|= IN6PTON_COLON_1_2;
	269	state &= ~IN6PTON_DELIM;
	270	}
	271	if (d + 2 >= dbuf + sizeof(dbuf)) {
272	state &= ~(IN6PTON_COLON_1\|IN6PTON_COLON_1_2);
273	}
274	cont:
275	if ((dc && d + 4 < dbuf + sizeof(dbuf)) \|\|
276	d + 4 == dbuf + sizeof(dbuf)) {
277	state \|= IN6PTON_DOT;
278	}
279	if (d >= dbuf + sizeof(dbuf)) {
280	state &= ~(IN6PTON_XDIGIT\|IN6PTON_COLON_MASK);
281	}
282	s++;
283	srclen--;
284	}
285
286	i = 15; d--;
287
288	if (dc) {
289	while(d >= dc)
290	dst[i--] = *d--;
291	while(i >= dc - dbuf)
292	dst[i--] = 0;
293	while(i >= 0)
294	dst[i--] = *d--;
295	} else
296	memcpy(dst, dbuf, sizeof(dbuf));
297
298	ret = 1;
299	out:
300	if (end)
301	*end = s;
302	return ret;
303	}
1aaec67f	304	EXPORT_SYMBOL(in6_pton);
a99a00cf PM	305
	306	void inet_proto_csum_replace4(__sum16 sum, struct sk_buff skb,
	307	__be32 from, __be32 to, int pseudohdr)
	308	{
	309	__be32 diff[] = { ~from, to };
	310	if (skb->ip_summed != CHECKSUM_PARTIAL) {
	311	*sum = csum_fold(csum_partial(diff, sizeof(diff),
	312	~csum_unfold(*sum)));
	313	if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
	314	skb->csum = ~csum_partial(diff, sizeof(diff),
	315	~skb->csum);
	316	} else if (pseudohdr)
	317	*sum = ~csum_fold(csum_partial(diff, sizeof(diff),
	318	csum_unfold(*sum)));
	319	}
	320	EXPORT_SYMBOL(inet_proto_csum_replace4);
4940fc88	321
2cf545e8 PM	322	void inet_proto_csum_replace16(__sum16 sum, struct sk_buff skb,
	323	const __be32 from, const __be32 to,
	324	int pseudohdr)
	325	{
	326	__be32 diff[] = {
	327	~from[0], ~from[1], ~from[2], ~from[3],
	328	to[0], to[1], to[2], to[3],
	329	};
	330	if (skb->ip_summed != CHECKSUM_PARTIAL) {
	331	*sum = csum_fold(csum_partial(diff, sizeof(diff),
	332	~csum_unfold(*sum)));
	333	if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
	334	skb->csum = ~csum_partial(diff, sizeof(diff),
	335	~skb->csum);
	336	} else if (pseudohdr)
	337	*sum = ~csum_fold(csum_partial(diff, sizeof(diff),
	338	csum_unfold(*sum)));
	339	}
	340	EXPORT_SYMBOL(inet_proto_csum_replace16);