xref: /dragonfly/lib/libc/inet/inet_pton.c (revision 81c11cd3)
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)
19 static const char rcsid[] = "$Id: inet_pton.c,v 1.5 2005/07/28 06:51:47 marka Exp $";
20 #endif /* LIBC_SCCS and not lint */
21 
22 #include "port_before.h"
23 #include <sys/param.h>
24 #include <sys/types.h>
25 #include <sys/socket.h>
26 #include <netinet/in.h>
27 #include <arpa/inet.h>
28 #include <arpa/nameser.h>
29 #include <string.h>
30 #include <errno.h>
31 #include "port_after.h"
32 
33 /*%
34  * WARNING: Don't even consider trying to compile this on a system where
35  * sizeof(int) < 4.  sizeof(int) > 4 is fine; all the world's not a VAX.
36  */
37 
38 static int	inet_pton4 __P((const char *src, u_char *dst));
39 static int	inet_pton6 __P((const char *src, u_char *dst));
40 
41 /* int
42  * inet_pton(af, src, dst)
43  *	convert from presentation format (which usually means ASCII printable)
44  *	to network format (which is usually some kind of binary format).
45  * return:
46  *	1 if the address was valid for the specified address family
47  *	0 if the address wasn't valid (`dst' is untouched in this case)
48  *	-1 if some other error occurred (`dst' is untouched in this case, too)
49  * author:
50  *	Paul Vixie, 1996.
51  */
52 int
53 inet_pton(af, src, dst)
54 	int af;
55 	const char *src;
56 	void *dst;
57 {
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  */
80 static int
81 inet_pton4(src, dst)
82 	const char *src;
83 	u_char *dst;
84 {
85 	static const char digits[] = "0123456789";
86 	int saw_digit, octets, ch;
87 	u_char tmp[NS_INADDRSZ], *tp;
88 
89 	saw_digit = 0;
90 	octets = 0;
91 	*(tp = tmp) = 0;
92 	while ((ch = *src++) != '\0') {
93 		const char *pch;
94 
95 		if ((pch = strchr(digits, ch)) != NULL) {
96 			u_int new = *tp * 10 + (pch - digits);
97 
98 			if (saw_digit && *tp == 0)
99 				return (0);
100 			if (new > 255)
101 				return (0);
102 			*tp = new;
103 			if (!saw_digit) {
104 				if (++octets > 4)
105 					return (0);
106 				saw_digit = 1;
107 			}
108 		} else if (ch == '.' && saw_digit) {
109 			if (octets == 4)
110 				return (0);
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  */
135 static int
136 inet_pton6(src, dst)
137 	const char *src;
138 	u_char *dst;
139 {
140 	static const char xdigits_l[] = "0123456789abcdef",
141 			  xdigits_u[] = "0123456789ABCDEF";
142 	u_char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
143 	const char *xdigits, *curtok;
144 	int ch, seen_xdigits;
145 	u_int val;
146 
147 	memset((tp = tmp), '\0', NS_IN6ADDRSZ);
148 	endp = tp + NS_IN6ADDRSZ;
149 	colonp = NULL;
150 	/* Leading :: requires some special handling. */
151 	if (*src == ':')
152 		if (*++src != ':')
153 			return (0);
154 	curtok = src;
155 	seen_xdigits = 0;
156 	val = 0;
157 	while ((ch = *src++) != '\0') {
158 		const char *pch;
159 
160 		if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
161 			pch = strchr((xdigits = xdigits_u), ch);
162 		if (pch != NULL) {
163 			val <<= 4;
164 			val |= (pch - xdigits);
165 			if (++seen_xdigits > 4)
166 				return (0);
167 			continue;
168 		}
169 		if (ch == ':') {
170 			curtok = src;
171 			if (!seen_xdigits) {
172 				if (colonp)
173 					return (0);
174 				colonp = tp;
175 				continue;
176 			} else if (*src == '\0') {
177 				return (0);
178 			}
179 			if (tp + NS_INT16SZ > endp)
180 				return (0);
181 			*tp++ = (u_char) (val >> 8) & 0xff;
182 			*tp++ = (u_char) val & 0xff;
183 			seen_xdigits = 0;
184 			val = 0;
185 			continue;
186 		}
187 		if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
188 		    inet_pton4(curtok, tp) > 0) {
189 			tp += NS_INADDRSZ;
190 			seen_xdigits = 0;
191 			break;	/*%< '\\0' was seen by inet_pton4(). */
192 		}
193 		return (0);
194 	}
195 	if (seen_xdigits) {
196 		if (tp + NS_INT16SZ > endp)
197 			return (0);
198 		*tp++ = (u_char) (val >> 8) & 0xff;
199 		*tp++ = (u_char) val & 0xff;
200 	}
201 	if (colonp != NULL) {
202 		/*
203 		 * Since some memmove()'s erroneously fail to handle
204 		 * overlapping regions, we'll do the shift by hand.
205 		 */
206 		const int n = tp - colonp;
207 		int i;
208 
209 		if (tp == endp)
210 			return (0);
211 		for (i = 1; i <= n; i++) {
212 			endp[- i] = colonp[n - i];
213 			colonp[n - i] = 0;
214 		}
215 		tp = endp;
216 	}
217 	if (tp != endp)
218 		return (0);
219 	memcpy(dst, tmp, NS_IN6ADDRSZ);
220 	return (1);
221 }
222 
223 #ifdef _LIBC
224 /*
225  * Weak aliases for applications that use certain private entry points,
226  * and fail to include <arpa/inet.h>.
227  */
228 #undef inet_pton
229 __weak_reference(__inet_pton, inet_pton);
230 #endif
231 /*! \file */
232