/contrib/bind9/lib/isc/inet_pton.c

  1/*
  2 * Copyright (C) 2004, 2005, 2007  Internet Systems Consortium, Inc. ("ISC")
  3 * Copyright (C) 1996-2003  Internet Software Consortium.
  4 *
  5 * Permission to use, copy, modify, and/or distribute this software for any
  6 * purpose with or without fee is hereby granted, provided that the above
  7 * copyright notice and this permission notice appear in all copies.
  8 *
  9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
 10 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 11 * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
 12 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
 13 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
 14 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 15 * PERFORMANCE OF THIS SOFTWARE.
 16 */
 17
 18/*! \file */
 19
 20#if defined(LIBC_SCCS) && !defined(lint)
 21static char rcsid[] =
 22	"$Id: inet_pton.c,v 1.19 2007/06/19 23:47:17 tbox Exp $";
 23#endif /* LIBC_SCCS and not lint */
 24
 25#include <config.h>
 26
 27#include <errno.h>
 28#include <string.h>
 29
 30#include <isc/net.h>
 31
 32/*% INT16 Size */
 33#define NS_INT16SZ	 2
 34/*% IPv4 Address Size */
 35#define NS_INADDRSZ	 4
 36/*% IPv6 Address Size */
 37#define NS_IN6ADDRSZ	16
 38
 39/*
 40 * WARNING: Don't even consider trying to compile this on a system where
 41 * sizeof(int) < 4.  sizeof(int) > 4 is fine; all the world's not a VAX.
 42 */
 43
 44static int inet_pton4(const char *src, unsigned char *dst);
 45static int inet_pton6(const char *src, unsigned char *dst);
 46
 47/*% 
 48 *	convert from presentation format (which usually means ASCII printable)
 49 *	to network format (which is usually some kind of binary format).
 50 * \return
 51 *	1 if the address was valid for the specified address family
 52 *	0 if the address wasn't valid (`dst' is untouched in this case)
 53 *	-1 if some other error occurred (`dst' is untouched in this case, too)
 54 * \author
 55 *	Paul Vixie, 1996.
 56 */
 57int
 58isc_net_pton(int af, const char *src, void *dst) {
 59	switch (af) {
 60	case AF_INET:
 61		return (inet_pton4(src, dst));
 62	case AF_INET6:
 63		return (inet_pton6(src, dst));
 64	default:
 65		errno = EAFNOSUPPORT;
 66		return (-1);
 67	}
 68	/* NOTREACHED */
 69}
 70
 71/*!\fn static int inet_pton4(const char *src, unsigned char *dst)
 72 * \brief
 73 *	like inet_aton() but without all the hexadecimal and shorthand.
 74 * \return
 75 *	1 if `src' is a valid dotted quad, else 0.
 76 * \note
 77 *	does not touch `dst' unless it's returning 1.
 78 * \author
 79 *	Paul Vixie, 1996.
 80 */
 81static int
 82inet_pton4(const char *src, unsigned char *dst) {
 83	static const char digits[] = "0123456789";
 84	int saw_digit, octets, ch;
 85	unsigned char tmp[NS_INADDRSZ], *tp;
 86
 87	saw_digit = 0;
 88	octets = 0;
 89	*(tp = tmp) = 0;
 90	while ((ch = *src++) != '\0') {
 91		const char *pch;
 92
 93		if ((pch = strchr(digits, ch)) != NULL) {
 94			unsigned int new = *tp * 10 + (pch - digits);
 95
 96			if (saw_digit && *tp == 0)
 97				return (0);
 98			if (new > 255)
 99				return (0);
100			*tp = new;
101			if (!saw_digit) {
102				if (++octets > 4)
103					return (0);
104				saw_digit = 1;
105			}
106		} else if (ch == '.' && saw_digit) {
107			if (octets == 4)
108				return (0);
109			*++tp = 0;
110			saw_digit = 0;
111		} else
112			return (0);
113	}
114	if (octets < 4)
115		return (0);
116	memcpy(dst, tmp, NS_INADDRSZ);
117	return (1);
118}
119
120/*%
121 *	convert presentation level address to network order binary form.
122 * \return
123 *	1 if `src' is a valid [RFC1884 2.2] address, else 0.
124 * \note
125 *	(1) does not touch `dst' unless it's returning 1.
126 * \note
127 *	(2) :: in a full address is silently ignored.
128 * \author
129 *	inspired by Mark Andrews.
130 * \author
131 *	Paul Vixie, 1996.
132 */
133static int
134inet_pton6(const char *src, unsigned char *dst) {
135	static const char xdigits_l[] = "0123456789abcdef",
136			  xdigits_u[] = "0123456789ABCDEF";
137	unsigned char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
138	const char *xdigits, *curtok;
139	int ch, seen_xdigits;
140	unsigned int val;
141
142	memset((tp = tmp), '\0', NS_IN6ADDRSZ);
143	endp = tp + NS_IN6ADDRSZ;
144	colonp = NULL;
145	/* Leading :: requires some special handling. */
146	if (*src == ':')
147		if (*++src != ':')
148			return (0);
149	curtok = src;
150	seen_xdigits = 0;
151	val = 0;
152	while ((ch = *src++) != '\0') {
153		const char *pch;
154
155		if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
156			pch = strchr((xdigits = xdigits_u), ch);
157		if (pch != NULL) {
158			val <<= 4;
159			val |= (pch - xdigits);
160			if (++seen_xdigits > 4)
161				return (0);
162			continue;
163		}
164		if (ch == ':') {
165			curtok = src;
166			if (!seen_xdigits) {
167				if (colonp)
168					return (0);
169				colonp = tp;
170				continue;
171			}
172			if (tp + NS_INT16SZ > endp)
173				return (0);
174			*tp++ = (unsigned char) (val >> 8) & 0xff;
175			*tp++ = (unsigned char) val & 0xff;
176			seen_xdigits = 0;
177			val = 0;
178			continue;
179		}
180		if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
181		    inet_pton4(curtok, tp) > 0) {
182			tp += NS_INADDRSZ;
183			seen_xdigits = 0;
184			break;	/* '\0' was seen by inet_pton4(). */
185		}
186		return (0);
187	}
188	if (seen_xdigits) {
189		if (tp + NS_INT16SZ > endp)
190			return (0);
191		*tp++ = (unsigned char) (val >> 8) & 0xff;
192		*tp++ = (unsigned char) val & 0xff;
193	}
194	if (colonp != NULL) {
195		/*
196		 * Since some memmove()'s erroneously fail to handle
197		 * overlapping regions, we'll do the shift by hand.
198		 */
199		const int n = tp - colonp;
200		int i;
201
202		if (tp == endp)
203			return (0);
204		for (i = 1; i <= n; i++) {
205			endp[- i] = colonp[n - i];
206			colonp[n - i] = 0;
207		}
208		tp = endp;
209	}
210	if (tp != endp)
211		return (0);
212	memcpy(dst, tmp, NS_IN6ADDRSZ);
213	return (1);
214}