xref: /netbsd-src/lib/libc/inet/inet_pton.c (revision 39e7bb7142b1ea672550d753937633b9bf7077fb)
1 /*	$NetBSD: inet_pton.c,v 1.1.1.1 2004/05/20 22:29:02 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
5  * Copyright (c) 1996,1999 by Internet Software Consortium.
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
17  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 
20 #if defined(LIBC_SCCS) && !defined(lint)
21 static const char rcsid[] = "Id: inet_pton.c,v 1.2.206.1 2004/03/09 08:33:33 marka Exp";
22 #endif /* LIBC_SCCS and not lint */
23 
24 #include "port_before.h"
25 #include <sys/param.h>
26 #include <sys/types.h>
27 #include <sys/socket.h>
28 #include <netinet/in.h>
29 #include <arpa/inet.h>
30 #include <arpa/nameser.h>
31 #include <string.h>
32 #include <errno.h>
33 #include "port_after.h"
34 
35 /*
36  * WARNING: Don't even consider trying to compile this on a system where
37  * sizeof(int) < 4.  sizeof(int) > 4 is fine; all the world's not a VAX.
38  */
39 
40 static int	inet_pton4 __P((const char *src, u_char *dst));
41 static int	inet_pton6 __P((const char *src, u_char *dst));
42 
43 /* int
44  * inet_pton(af, src, dst)
45  *	convert from presentation format (which usually means ASCII printable)
46  *	to network format (which is usually some kind of binary format).
47  * return:
48  *	1 if the address was valid for the specified address family
49  *	0 if the address wasn't valid (`dst' is untouched in this case)
50  *	-1 if some other error occurred (`dst' is untouched in this case, too)
51  * author:
52  *	Paul Vixie, 1996.
53  */
54 int
55 inet_pton(af, src, dst)
56 	int af;
57 	const char *src;
58 	void *dst;
59 {
60 	switch (af) {
61 	case AF_INET:
62 		return (inet_pton4(src, dst));
63 	case AF_INET6:
64 		return (inet_pton6(src, dst));
65 	default:
66 		errno = EAFNOSUPPORT;
67 		return (-1);
68 	}
69 	/* NOTREACHED */
70 }
71 
72 /* int
73  * inet_pton4(src, dst)
74  *	like inet_aton() but without all the hexadecimal and shorthand.
75  * return:
76  *	1 if `src' is a valid dotted quad, else 0.
77  * notice:
78  *	does not touch `dst' unless it's returning 1.
79  * author:
80  *	Paul Vixie, 1996.
81  */
82 static int
83 inet_pton4(src, dst)
84 	const char *src;
85 	u_char *dst;
86 {
87 	static const char digits[] = "0123456789";
88 	int saw_digit, octets, ch;
89 	u_char tmp[NS_INADDRSZ], *tp;
90 
91 	saw_digit = 0;
92 	octets = 0;
93 	*(tp = tmp) = 0;
94 	while ((ch = *src++) != '\0') {
95 		const char *pch;
96 
97 		if ((pch = strchr(digits, ch)) != NULL) {
98 			u_int new = *tp * 10 + (pch - digits);
99 
100 			if (saw_digit && *tp == 0)
101 				return (0);
102 			if (new > 255)
103 				return (0);
104 			*tp = new;
105 			if (!saw_digit) {
106 				if (++octets > 4)
107 					return (0);
108 				saw_digit = 1;
109 			}
110 		} else if (ch == '.' && saw_digit) {
111 			if (octets == 4)
112 				return (0);
113 			*++tp = 0;
114 			saw_digit = 0;
115 		} else
116 			return (0);
117 	}
118 	if (octets < 4)
119 		return (0);
120 	memcpy(dst, tmp, NS_INADDRSZ);
121 	return (1);
122 }
123 
124 /* int
125  * inet_pton6(src, dst)
126  *	convert presentation level address to network order binary form.
127  * return:
128  *	1 if `src' is a valid [RFC1884 2.2] address, else 0.
129  * notice:
130  *	(1) does not touch `dst' unless it's returning 1.
131  *	(2) :: in a full address is silently ignored.
132  * credit:
133  *	inspired by Mark Andrews.
134  * author:
135  *	Paul Vixie, 1996.
136  */
137 static int
138 inet_pton6(src, dst)
139 	const char *src;
140 	u_char *dst;
141 {
142 	static const char xdigits_l[] = "0123456789abcdef",
143 			  xdigits_u[] = "0123456789ABCDEF";
144 	u_char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
145 	const char *xdigits, *curtok;
146 	int ch, saw_xdigit;
147 	u_int val;
148 
149 	memset((tp = tmp), '\0', NS_IN6ADDRSZ);
150 	endp = tp + NS_IN6ADDRSZ;
151 	colonp = NULL;
152 	/* Leading :: requires some special handling. */
153 	if (*src == ':')
154 		if (*++src != ':')
155 			return (0);
156 	curtok = src;
157 	saw_xdigit = 0;
158 	val = 0;
159 	while ((ch = *src++) != '\0') {
160 		const char *pch;
161 
162 		if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
163 			pch = strchr((xdigits = xdigits_u), ch);
164 		if (pch != NULL) {
165 			val <<= 4;
166 			val |= (pch - xdigits);
167 			if (val > 0xffff)
168 				return (0);
169 			saw_xdigit = 1;
170 			continue;
171 		}
172 		if (ch == ':') {
173 			curtok = src;
174 			if (!saw_xdigit) {
175 				if (colonp)
176 					return (0);
177 				colonp = tp;
178 				continue;
179 			} else if (*src == '\0') {
180 				return (0);
181 			}
182 			if (tp + NS_INT16SZ > endp)
183 				return (0);
184 			*tp++ = (u_char) (val >> 8) & 0xff;
185 			*tp++ = (u_char) val & 0xff;
186 			saw_xdigit = 0;
187 			val = 0;
188 			continue;
189 		}
190 		if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
191 		    inet_pton4(curtok, tp) > 0) {
192 			tp += NS_INADDRSZ;
193 			saw_xdigit = 0;
194 			break;	/* '\0' was seen by inet_pton4(). */
195 		}
196 		return (0);
197 	}
198 	if (saw_xdigit) {
199 		if (tp + NS_INT16SZ > endp)
200 			return (0);
201 		*tp++ = (u_char) (val >> 8) & 0xff;
202 		*tp++ = (u_char) val & 0xff;
203 	}
204 	if (colonp != NULL) {
205 		/*
206 		 * Since some memmove()'s erroneously fail to handle
207 		 * overlapping regions, we'll do the shift by hand.
208 		 */
209 		const int n = tp - colonp;
210 		int i;
211 
212 		if (tp == endp)
213 			return (0);
214 		for (i = 1; i <= n; i++) {
215 			endp[- i] = colonp[n - i];
216 			colonp[n - i] = 0;
217 		}
218 		tp = endp;
219 	}
220 	if (tp != endp)
221 		return (0);
222 	memcpy(dst, tmp, NS_IN6ADDRSZ);
223 	return (1);
224 }
225