1 /* $OpenBSD: inet_pton.c,v 1.7 2006/12/30 23:37:37 itojun Exp $ */
2
3 /* Copyright (c) 1996 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 INTERNET SOFTWARE CONSORTIUM DISCLAIMS
10 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
11 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
12 * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
13 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
14 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
15 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
16 * SOFTWARE.
17 */
18
19 #include <sys/param.h>
20 #include <sys/types.h>
21 #include <sys/socket.h>
22 #include <netinet/in.h>
23 #include <arpa/inet.h>
24 #include "arpa_nameser.h"
25 #include <string.h>
26 #include <errno.h>
27
28 /*
29 * WARNING: Don't even consider trying to compile this on a system where
30 * sizeof(int) < 4. sizeof(int) > 4 is fine; all the world's not a VAX.
31 */
32
33 static int inet_pton4(const char *src, u_char *dst);
34 static int inet_pton6(const char *src, u_char *dst);
35
36 /* int
37 * inet_pton(af, src, dst)
38 * convert from presentation format (which usually means ASCII printable)
39 * to network format (which is usually some kind of binary format).
40 * return:
41 * 1 if the address was valid for the specified address family
42 * 0 if the address wasn't valid (`dst' is untouched in this case)
43 * -1 if some other error occurred (`dst' is untouched in this case, too)
44 * author:
45 * Paul Vixie, 1996.
46 */
47 int
inet_pton(int af,const char * src,void * dst)48 inet_pton(int af, const char *src, void *dst)
49 {
50 switch (af) {
51 case AF_INET:
52 return (inet_pton4(src, dst));
53 case AF_INET6:
54 return (inet_pton6(src, dst));
55 default:
56 errno = EAFNOSUPPORT;
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 */
72 static int
inet_pton4(const char * src,u_char * dst)73 inet_pton4(const char *src, u_char *dst)
74 {
75 static const char digits[] = "0123456789";
76 int saw_digit, octets, ch;
77 u_char tmp[INADDRSZ], *tp;
78
79 saw_digit = 0;
80 octets = 0;
81 *(tp = tmp) = 0;
82 while ((ch = *src++) != '\0') {
83 const char *pch;
84
85 if ((pch = strchr(digits, ch)) != NULL) {
86 u_int new = *tp * 10 + (pch - digits);
87
88 if (new > 255)
89 return (0);
90 if (! saw_digit) {
91 if (++octets > 4)
92 return (0);
93 saw_digit = 1;
94 }
95 *tp = new;
96 } else if (ch == '.' && saw_digit) {
97 if (octets == 4)
98 return (0);
99 *++tp = 0;
100 saw_digit = 0;
101 } else
102 return (0);
103 }
104 if (octets < 4)
105 return (0);
106
107 memcpy(dst, tmp, INADDRSZ);
108 return (1);
109 }
110
111 /* int
112 * inet_pton6(src, dst)
113 * convert presentation level address to network order binary form.
114 * return:
115 * 1 if `src' is a valid [RFC1884 2.2] address, else 0.
116 * notice:
117 * (1) does not touch `dst' unless it's returning 1.
118 * (2) :: in a full address is silently ignored.
119 * credit:
120 * inspired by Mark Andrews.
121 * author:
122 * Paul Vixie, 1996.
123 */
124 static int
inet_pton6(const char * src,u_char * dst)125 inet_pton6(const char *src, u_char *dst)
126 {
127 static const char xdigits_l[] = "0123456789abcdef",
128 xdigits_u[] = "0123456789ABCDEF";
129 u_char tmp[IN6ADDRSZ], *tp, *endp, *colonp;
130 const char *xdigits, *curtok;
131 int ch, saw_xdigit, count_xdigit;
132 u_int val;
133
134 memset((tp = tmp), '\0', IN6ADDRSZ);
135 endp = tp + IN6ADDRSZ;
136 colonp = NULL;
137 /* Leading :: requires some special handling. */
138 if (*src == ':')
139 if (*++src != ':')
140 return (0);
141 curtok = src;
142 saw_xdigit = count_xdigit = 0;
143 val = 0;
144 while ((ch = *src++) != '\0') {
145 const char *pch;
146
147 if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
148 pch = strchr((xdigits = xdigits_u), ch);
149 if (pch != NULL) {
150 if (count_xdigit >= 4)
151 return (0);
152 val <<= 4;
153 val |= (pch - xdigits);
154 if (val > 0xffff)
155 return (0);
156 saw_xdigit = 1;
157 count_xdigit++;
158 continue;
159 }
160 if (ch == ':') {
161 curtok = src;
162 if (!saw_xdigit) {
163 if (colonp)
164 return (0);
165 colonp = tp;
166 continue;
167 } else if (*src == '\0') {
168 return (0);
169 }
170 if (tp + INT16SZ > endp)
171 return (0);
172 *tp++ = (u_char) (val >> 8) & 0xff;
173 *tp++ = (u_char) val & 0xff;
174 saw_xdigit = 0;
175 count_xdigit = 0;
176 val = 0;
177 continue;
178 }
179 if (ch == '.' && ((tp + INADDRSZ) <= endp) &&
180 inet_pton4(curtok, tp) > 0) {
181 tp += INADDRSZ;
182 saw_xdigit = 0;
183 count_xdigit = 0;
184 break; /* '\0' was seen by inet_pton4(). */
185 }
186 return (0);
187 }
188 if (saw_xdigit) {
189 if (tp + INT16SZ > endp)
190 return (0);
191 *tp++ = (u_char) (val >> 8) & 0xff;
192 *tp++ = (u_char) val & 0xff;
193 }
194 if (colonp != NULL) {
195 /*
196 * Since some memmove()'s erroneously fail to handle
197 * overlapping regions, we'll do the shift by hand.
198 */
199 const int n = tp - colonp;
200 int i;
201
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, IN6ADDRSZ);
211 return (1);
212 }
213