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#if defined(LIBC_SCCS) && !defined(lint)
18static const char rcsid[] = "$Id: inet_pton.c,v 1.3.18.2 2005/07/28 07:38:07 marka Exp $";
19#endif /* LIBC_SCCS and not lint */
20
21#include <string.h>
22
23#include <sys/param.h>
24#include <sys/socket.h>
25#include <sys/systm.h>
26
27#include <netinet/in.h>
28
29/*%
30 * WARNING: Don't even consider trying to compile this on a system where
31 * sizeof(int) < 4.  sizeof(int) > 4 is fine; all the world's not a VAX.
32 */
33
34static int	inet_pton4(const char *src, u_char *dst);
35static int	inet_pton6(const char *src, u_char *dst);
36
37/* int
38 * inet_pton(af, src, dst)
39 *	convert from presentation format (which usually means ASCII printable)
40 *	to network format (which is usually some kind of binary format).
41 * return:
42 *	1 if the address was valid for the specified address family
43 *	0 if the address wasn't valid (`dst' is untouched in this case)
44 *	-1 if some other error occurred (`dst' is untouched in this case, too)
45 * author:
46 *	Paul Vixie, 1996.
47 */
48int
49inet_pton(int af, const char *src, void *dst)
50{
51	switch (af) {
52	case AF_INET:
53		return (inet_pton4(src, dst));
54	case AF_INET6:
55		return (inet_pton6(src, dst));
56	default:
57		return (-1);
58	}
59	/* NOTREACHED */
60}
61
62/* int
63 * inet_pton4(src, dst)
64 *	like inet_aton() but without all the hexadecimal and shorthand.
65 * return:
66 *	1 if `src' is a valid dotted quad, else 0.
67 * notice:
68 *	does not touch `dst' unless it's returning 1.
69 * author:
70 *	Paul Vixie, 1996.
71 */
72static int
73inet_pton4(const char *src, u_char *dst)
74{
75	static const char digits[] = "0123456789";
76	int saw_digit, octets, ch;
77#define NS_INADDRSZ	4
78	u_char tmp[NS_INADDRSZ], *tp;
79
80	saw_digit = 0;
81	octets = 0;
82	*(tp = tmp) = 0;
83	while ((ch = *src++) != '\0') {
84		const char *pch;
85
86		if ((pch = strchr(digits, ch)) != NULL) {
87			u_int new = *tp * 10 + (pch - digits);
88
89			if (saw_digit && *tp == 0)
90				return (0);
91			if (new > 255)
92				return (0);
93			*tp = new;
94			if (!saw_digit) {
95				if (++octets > 4)
96					return (0);
97				saw_digit = 1;
98			}
99		} else if (ch == '.' && saw_digit) {
100			if (octets == 4)
101				return (0);
102			*++tp = 0;
103			saw_digit = 0;
104		} else
105			return (0);
106	}
107	if (octets < 4)
108		return (0);
109	memcpy(dst, tmp, NS_INADDRSZ);
110	return (1);
111}
112
113/* int
114 * inet_pton6(src, dst)
115 *	convert presentation level address to network order binary form.
116 * return:
117 *	1 if `src' is a valid [RFC1884 2.2] address, else 0.
118 * notice:
119 *	(1) does not touch `dst' unless it's returning 1.
120 *	(2) :: in a full address is silently ignored.
121 * credit:
122 *	inspired by Mark Andrews.
123 * author:
124 *	Paul Vixie, 1996.
125 */
126static int
127inet_pton6(const char *src, u_char *dst)
128{
129	static const char xdigits_l[] = "0123456789abcdef",
130			  xdigits_u[] = "0123456789ABCDEF";
131#define NS_IN6ADDRSZ	16
132#define NS_INT16SZ	2
133	u_char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
134	const char *xdigits, *curtok;
135	int ch, seen_xdigits;
136	u_int val;
137
138	memset((tp = tmp), '\0', NS_IN6ADDRSZ);
139	endp = tp + NS_IN6ADDRSZ;
140	colonp = NULL;
141	/* Leading :: requires some special handling. */
142	if (*src == ':')
143		if (*++src != ':')
144			return (0);
145	curtok = src;
146	seen_xdigits = 0;
147	val = 0;
148	while ((ch = *src++) != '\0') {
149		const char *pch;
150
151		if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
152			pch = strchr((xdigits = xdigits_u), ch);
153		if (pch != NULL) {
154			val <<= 4;
155			val |= (pch - xdigits);
156			if (++seen_xdigits > 4)
157				return (0);
158			continue;
159		}
160		if (ch == ':') {
161			curtok = src;
162			if (!seen_xdigits) {
163				if (colonp)
164					return (0);
165				colonp = tp;
166				continue;
167			} else if (*src == '\0') {
168				return (0);
169			}
170			if (tp + NS_INT16SZ > endp)
171				return (0);
172			*tp++ = (u_char) (val >> 8) & 0xff;
173			*tp++ = (u_char) val & 0xff;
174			seen_xdigits = 0;
175			val = 0;
176			continue;
177		}
178		if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
179		    inet_pton4(curtok, tp) > 0) {
180			tp += NS_INADDRSZ;
181			seen_xdigits = 0;
182			break;	/*%< '\\0' was seen by inet_pton4(). */
183		}
184		return (0);
185	}
186	if (seen_xdigits) {
187		if (tp + NS_INT16SZ > endp)
188			return (0);
189		*tp++ = (u_char) (val >> 8) & 0xff;
190		*tp++ = (u_char) val & 0xff;
191	}
192	if (colonp != NULL) {
193		/*
194		 * Since some memmove()'s erroneously fail to handle
195		 * overlapping regions, we'll do the shift by hand.
196		 */
197		const int n = tp - colonp;
198		int i;
199
200		if (tp == endp)
201			return (0);
202		for (i = 1; i <= n; i++) {
203			endp[- i] = colonp[n - i];
204			colonp[n - i] = 0;
205		}
206		tp = endp;
207	}
208	if (tp != endp)
209		return (0);
210	memcpy(dst, tmp, NS_IN6ADDRSZ);
211	return (1);
212}
213