1/*
2 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
3 * Copyright (c) 1996,1999 by Internet Software Consortium.
4 *
5 * Permission to use, copy, modify, and 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
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
15 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18#if defined(LIBC_SCCS) && !defined(lint)
19static const char rcsid[] = "$Id: inet_pton.c,v 1.3.18.2 2005/07/28 07:38:07 marka Exp $";
20#endif /* LIBC_SCCS and not lint */
21#include <sys/cdefs.h>
22__FBSDID("$FreeBSD$");
23
24#include <sys/param.h>
25#include <sys/types.h>
26#include <sys/socket.h>
27#include <netinet/in.h>
28#include <arpa/inet.h>
29#include <string.h>
30#include <errno.h>
31
32/*%
33 * WARNING: Don't even consider trying to compile this on a system where
34 * sizeof(int) < 4.  sizeof(int) > 4 is fine; all the world's not a VAX.
35 */
36
37static int	inet_pton4(const char *src, u_char *dst);
38static int	inet_pton6(const char *src, u_char *dst);
39
40/* int
41 * inet_pton(af, src, dst)
42 *	convert from presentation format (which usually means ASCII printable)
43 *	to network format (which is usually some kind of binary format).
44 * return:
45 *	1 if the address was valid for the specified address family
46 *	0 if the address wasn't valid (`dst' is untouched in this case)
47 *	-1 if some other error occurred (`dst' is untouched in this case, too)
48 * author:
49 *	Paul Vixie, 1996.
50 */
51int
52inet_pton(int af, const char * __restrict src, void * __restrict dst)
53{
54	switch (af) {
55	case AF_INET:
56		return (inet_pton4(src, dst));
57	case AF_INET6:
58		return (inet_pton6(src, dst));
59	default:
60		errno = EAFNOSUPPORT;
61		return (-1);
62	}
63	/* NOTREACHED */
64}
65
66/* int
67 * inet_pton4(src, dst)
68 *	like inet_aton() but without all the hexadecimal and shorthand.
69 * return:
70 *	1 if `src' is a valid dotted quad, else 0.
71 * notice:
72 *	does not touch `dst' unless it's returning 1.
73 * author:
74 *	Paul Vixie, 1996.
75 */
76static int
77inet_pton4(const char *src, u_char *dst)
78{
79	static const char digits[] = "0123456789";
80	int saw_digit, octets, ch;
81#define NS_INADDRSZ     4
82	u_char tmp[NS_INADDRSZ], *tp;
83
84	saw_digit = 0;
85	octets = 0;
86	*(tp = tmp) = 0;
87	while ((ch = *src++) != '\0') {
88		const char *pch;
89
90		if ((pch = strchr(digits, ch)) != NULL) {
91			u_int new = *tp * 10 + (pch - digits);
92
93			if (saw_digit && *tp == 0)
94				return (0);
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			*++tp = 0;
107			saw_digit = 0;
108		} else
109			return (0);
110	}
111	if (octets < 4)
112		return (0);
113	memcpy(dst, tmp, NS_INADDRSZ);
114	return (1);
115}
116
117/* int
118 * inet_pton6(src, dst)
119 *	convert presentation level address to network order binary form.
120 * return:
121 *	1 if `src' is a valid [RFC1884 2.2] address, else 0.
122 * notice:
123 *	(1) does not touch `dst' unless it's returning 1.
124 *	(2) :: in a full address is silently ignored.
125 * credit:
126 *	inspired by Mark Andrews.
127 * author:
128 *	Paul Vixie, 1996.
129 */
130static int
131inet_pton6(const char *src, u_char *dst)
132{
133	static const char xdigits_l[] = "0123456789abcdef",
134			  xdigits_u[] = "0123456789ABCDEF";
135#define NS_IN6ADDRSZ    16
136#define NS_INT16SZ      2
137	u_char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
138	const char *xdigits, *curtok;
139	int ch, seen_xdigits;
140	u_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			} else if (*src == '\0') {
172				return (0);
173			}
174			if (tp + NS_INT16SZ > endp)
175				return (0);
176			*tp++ = (u_char) (val >> 8) & 0xff;
177			*tp++ = (u_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++ = (u_char) (val >> 8) & 0xff;
194		*tp++ = (u_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		if (tp == endp)
205			return (0);
206		for (i = 1; i <= n; i++) {
207			endp[- i] = colonp[n - i];
208			colonp[n - i] = 0;
209		}
210		tp = endp;
211	}
212	if (tp != endp)
213		return (0);
214	memcpy(dst, tmp, NS_IN6ADDRSZ);
215	return (1);
216}
217