/contrib/bind9/lib/lwres/lwinetpton.c

  1/*
  2 * Copyright (C) 2004, 2005, 2007, 2011, 2012  Internet Systems Consortium, Inc. ("ISC")
  3 * Copyright (C) 1996-2001  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 lwinetpton.c
 19 */
 20
 21#if defined(LIBC_SCCS) && !defined(lint)
 22static char rcsid[] = "$Id$";
 23#endif /* LIBC_SCCS and not lint */
 24
 25#include <config.h>
 26
 27#include <errno.h>
 28#include <string.h>
 29
 30#include <lwres/net.h>
 31
 32#define NS_INT16SZ	 2
 33#define NS_INADDRSZ	 4
 34#define NS_IN6ADDRSZ	16
 35
 36/*
 37 * WARNING: Don't even consider trying to compile this on a system where
 38 * sizeof(int) < 4.  sizeof(int) > 4 is fine; all the world's not a VAX.
 39 */
 40
 41static int inet_pton4(const char *src, unsigned char *dst);
 42static int inet_pton6(const char *src, unsigned char *dst);
 43
 44/*!
 45 * int
 46 * lwres_net_pton(af, src, dst)
 47 *	convert from presentation format (which usually means ASCII printable)
 48 *	to network format (which is usually some kind of binary format).
 49 * return:
 50 *	1 if the address was valid for the specified address family
 51 *	0 if the address wasn't valid (`dst' is untouched in this case)
 52 *	-1 if some other error occurred (`dst' is untouched in this case, too)
 53 * author:
 54 *	Paul Vixie, 1996.
 55 */
 56int
 57lwres_net_pton(int af, const char *src, void *dst) {
 58	switch (af) {
 59	case AF_INET:
 60		return (inet_pton4(src, dst));
 61	case AF_INET6:
 62		return (inet_pton6(src, dst));
 63	default:
 64		errno = EAFNOSUPPORT;
 65		return (-1);
 66	}
 67	/* NOTREACHED */
 68}
 69
 70/*! int
 71 * inet_pton4(src, dst)
 72 *	like inet_aton() but without all the hexadecimal and shorthand.
 73 * return:
 74 *	1 if `src' is a valid dotted quad, else 0.
 75 * notice:
 76 *	does not touch `dst' unless it's returning 1.
 77 * author:
 78 *	Paul Vixie, 1996.
 79 */
 80static int
 81inet_pton4(const char *src, unsigned char *dst) {
 82	static const char digits[] = "0123456789";
 83	int saw_digit, octets, ch;
 84	unsigned char tmp[NS_INADDRSZ], *tp;
 85
 86	saw_digit = 0;
 87	octets = 0;
 88	*(tp = tmp) = 0;
 89	while ((ch = *src++) != '\0') {
 90		const char *pch;
 91
 92		if ((pch = strchr(digits, ch)) != NULL) {
 93			unsigned int new = *tp * 10 + (pch - digits);
 94
 95			if (new > 255)
 96				return (0);
 97			*tp = new;
 98			if (! saw_digit) {
 99				if (++octets > 4)
100					return (0);
101				saw_digit = 1;
102			}
103		} else if (ch == '.' && saw_digit) {
104			if (octets == 4)
105				return (0);
106			/*
107			 * "clang --analyse" generates warnings using:
108			 * 		*++tp = 0;
109			 */
110			tp++;
111			*tp = 0;
112			saw_digit = 0;
113		} else
114			return (0);
115	}
116	if (octets < 4)
117		return (0);
118	memcpy(dst, tmp, NS_INADDRSZ);
119	return (1);
120}
121
122/*! int
123 * inet_pton6(src, dst)
124 *	convert presentation level address to network order binary form.
125 * return:
126 *	1 if `src' is a valid [RFC1884 2.2] address, else 0.
127 * notice:
128 *	(1) does not touch `dst' unless it's returning 1.
129 *	(2) :: in a full address is silently ignored.
130 * credit:
131 *	inspired by Mark Andrews.
132 * author:
133 *	Paul Vixie, 1996.
134 */
135static int
136inet_pton6(const char *src, unsigned char *dst) {
137	static const char xdigits_l[] = "0123456789abcdef",
138			  xdigits_u[] = "0123456789ABCDEF";
139	unsigned char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
140	const char *xdigits, *curtok;
141	int ch, seen_xdigits;
142	unsigned int val;
143
144	memset((tp = tmp), '\0', NS_IN6ADDRSZ);
145	endp = tp + NS_IN6ADDRSZ;
146	colonp = NULL;
147	/* Leading :: requires some special handling. */
148	if (*src == ':')
149		if (*++src != ':')
150			return (0);
151	curtok = src;
152	seen_xdigits = 0;
153	val = 0;
154	while ((ch = *src++) != '\0') {
155		const char *pch;
156
157		if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
158			pch = strchr((xdigits = xdigits_u), ch);
159		if (pch != NULL) {
160			val <<= 4;
161			val |= (pch - xdigits);
162			if (++seen_xdigits > 4)
163				return (0);
164			continue;
165		}
166		if (ch == ':') {
167			curtok = src;
168			if (!seen_xdigits) {
169				if (colonp)
170					return (0);
171				colonp = tp;
172				continue;
173			}
174			if (tp + NS_INT16SZ > endp)
175				return (0);
176			*tp++ = (unsigned char) (val >> 8) & 0xff;
177			*tp++ = (unsigned char) val & 0xff;
178			seen_xdigits = 0;
179			val = 0;
180			continue;
181		}
182		if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
183		    inet_pton4(curtok, tp) > 0) {
184			tp += NS_INADDRSZ;
185			seen_xdigits = 0;
186			break;	/* '\0' was seen by inet_pton4(). */
187		}
188		return (0);
189	}
190	if (seen_xdigits) {
191		if (tp + NS_INT16SZ > endp)
192			return (0);
193		*tp++ = (unsigned char) (val >> 8) & 0xff;
194		*tp++ = (unsigned char) val & 0xff;
195	}
196	if (colonp != NULL) {
197		/*
198		 * Since some memmove()'s erroneously fail to handle
199		 * overlapping regions, we'll do the shift by hand.
200		 */
201		const int n = tp - colonp;
202		int i;
203
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}