1 /*-
2 * SPDX-License-Identifier: ISC
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 1.5 2005/07/28 06:51:47 marka Exp $";
22 #endif /* LIBC_SCCS and not lint */
23 #include <sys/cdefs.h>
24 #include "port_before.h"
25 #include <sys/param.h>
26 #include <sys/socket.h>
27 #include <netinet/in.h>
28 #include <arpa/inet.h>
29 #include <arpa/nameser.h>
30 #include <string.h>
31 #include <errno.h>
32 #include "port_after.h"
33
34 /*%
35 * WARNING: Don't even consider trying to compile this on a system where
36 * sizeof(int) < 4. sizeof(int) > 4 is fine; all the world's not a VAX.
37 */
38
39 static int inet_pton4(const char *src, u_char *dst);
40 static int inet_pton6(const char *src, u_char *dst);
41
42 /* int
43 * inet_pton(af, src, dst)
44 * convert from presentation format (which usually means ASCII printable)
45 * to network format (which is usually some kind of binary format).
46 * return:
47 * 1 if the address was valid for the specified address family
48 * 0 if the address wasn't valid (`dst' is untouched in this case)
49 * -1 if some other error occurred (`dst' is untouched in this case, too)
50 * author:
51 * Paul Vixie, 1996.
52 */
53 int
inet_pton(int af,const char * __restrict src,void * __restrict dst)54 inet_pton(int af, const char * __restrict src, void * __restrict dst)
55 {
56 switch (af) {
57 case AF_INET:
58 return (inet_pton4(src, dst));
59 case AF_INET6:
60 return (inet_pton6(src, dst));
61 default:
62 errno = EAFNOSUPPORT;
63 return (-1);
64 }
65 /* NOTREACHED */
66 }
67
68 /* int
69 * inet_pton4(src, dst)
70 * like inet_aton() but without all the hexadecimal and shorthand.
71 * return:
72 * 1 if `src' is a valid dotted quad, else 0.
73 * notice:
74 * does not touch `dst' unless it's returning 1.
75 * author:
76 * Paul Vixie, 1996.
77 */
78 static int
inet_pton4(const char * src,u_char * dst)79 inet_pton4(const char *src, u_char *dst)
80 {
81 static const char digits[] = "0123456789";
82 int saw_digit, octets, ch;
83 u_char tmp[NS_INADDRSZ], *tp;
84
85 saw_digit = 0;
86 octets = 0;
87 *(tp = tmp) = 0;
88 while ((ch = *src++) != '\0') {
89 const char *pch;
90
91 if ((pch = strchr(digits, ch)) != NULL) {
92 u_int new = *tp * 10 + (pch - digits);
93
94 if (saw_digit && *tp == 0)
95 return (0);
96 if (new > 255)
97 return (0);
98 *tp = new;
99 if (!saw_digit) {
100 if (++octets > 4)
101 return (0);
102 saw_digit = 1;
103 }
104 } else if (ch == '.' && saw_digit) {
105 if (octets == 4)
106 return (0);
107 *++tp = 0;
108 saw_digit = 0;
109 } else
110 return (0);
111 }
112 if (octets < 4)
113 return (0);
114 memcpy(dst, tmp, NS_INADDRSZ);
115 return (1);
116 }
117
118 /* int
119 * inet_pton6(src, dst)
120 * convert presentation level address to network order binary form.
121 * return:
122 * 1 if `src' is a valid [RFC1884 2.2] address, else 0.
123 * notice:
124 * (1) does not touch `dst' unless it's returning 1.
125 * (2) :: in a full address is silently ignored.
126 * credit:
127 * inspired by Mark Andrews.
128 * author:
129 * Paul Vixie, 1996.
130 */
131 static int
inet_pton6(const char * src,u_char * dst)132 inet_pton6(const char *src, u_char *dst)
133 {
134 static const char xdigits_l[] = "0123456789abcdef",
135 xdigits_u[] = "0123456789ABCDEF";
136 u_char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
137 const char *xdigits, *curtok;
138 int ch, seen_xdigits;
139 u_int val;
140
141 memset((tp = tmp), '\0', NS_IN6ADDRSZ);
142 endp = tp + NS_IN6ADDRSZ;
143 colonp = NULL;
144 /* Leading :: requires some special handling. */
145 if (*src == ':')
146 if (*++src != ':')
147 return (0);
148 curtok = src;
149 seen_xdigits = 0;
150 val = 0;
151 while ((ch = *src++) != '\0') {
152 const char *pch;
153
154 if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
155 pch = strchr((xdigits = xdigits_u), ch);
156 if (pch != NULL) {
157 val <<= 4;
158 val |= (pch - xdigits);
159 if (++seen_xdigits > 4)
160 return (0);
161 continue;
162 }
163 if (ch == ':') {
164 curtok = src;
165 if (!seen_xdigits) {
166 if (colonp)
167 return (0);
168 colonp = tp;
169 continue;
170 } else if (*src == '\0') {
171 return (0);
172 }
173 if (tp + NS_INT16SZ > endp)
174 return (0);
175 *tp++ = (u_char) (val >> 8) & 0xff;
176 *tp++ = (u_char) val & 0xff;
177 seen_xdigits = 0;
178 val = 0;
179 continue;
180 }
181 if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
182 inet_pton4(curtok, tp) > 0) {
183 tp += NS_INADDRSZ;
184 seen_xdigits = 0;
185 break; /*%< '\\0' was seen by inet_pton4(). */
186 }
187 return (0);
188 }
189 if (seen_xdigits) {
190 if (tp + NS_INT16SZ > endp)
191 return (0);
192 *tp++ = (u_char) (val >> 8) & 0xff;
193 *tp++ = (u_char) val & 0xff;
194 }
195 if (colonp != NULL) {
196 /*
197 * Since some memmove()'s erroneously fail to handle
198 * overlapping regions, we'll do the shift by hand.
199 */
200 const int n = tp - colonp;
201 int i;
202
203 if (tp == endp)
204 return (0);
205 for (i = 1; i <= n; i++) {
206 endp[- i] = colonp[n - i];
207 colonp[n - i] = 0;
208 }
209 tp = endp;
210 }
211 if (tp != endp)
212 return (0);
213 memcpy(dst, tmp, NS_IN6ADDRSZ);
214 return (1);
215 }
216
217 /*
218 * Weak aliases for applications that use certain private entry points,
219 * and fail to include <arpa/inet.h>.
220 */
221 #undef inet_pton
222 __weak_reference(__inet_pton, inet_pton);
223
224 /*! \file */
225