1 /* $OpenBSD: inet_pton.c,v 1.10 2015/09/13 21:36:08 guenther 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/types.h>
20 #include <sys/socket.h>
21 #include <netinet/in.h>
22 #include <arpa/inet.h>
23 #include <arpa/nameser.h>
24 #include <string.h>
25 #include <errno.h>
26
27 /*
28 * WARNING: Don't even consider trying to compile this on a system where
29 * sizeof(int) < 4. sizeof(int) > 4 is fine; all the world's not a VAX.
30 */
31
32 static int inet_pton4(const char *src, u_char *dst);
33 static int inet_pton6(const char *src, u_char *dst);
34
35 /* int
36 * inet_pton(af, src, dst)
37 * convert from presentation format (which usually means ASCII printable)
38 * to network format (which is usually some kind of binary format).
39 * return:
40 * 1 if the address was valid for the specified address family
41 * 0 if the address wasn't valid (`dst' is untouched in this case)
42 * -1 if some other error occurred (`dst' is untouched in this case, too)
43 * author:
44 * Paul Vixie, 1996.
45 */
46 int
inet_pton(int af,const char * src,void * dst)47 inet_pton(int af, const char *src, void *dst)
48 {
49 switch (af) {
50 case AF_INET:
51 return (inet_pton4(src, dst));
52 case AF_INET6:
53 return (inet_pton6(src, dst));
54 default:
55 errno = EAFNOSUPPORT;
56 return (-1);
57 }
58 /* NOTREACHED */
59 }
60 DEF_WEAK(inet_pton);
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 * does not touch `dst' unless it's returning 1.
118 * credit:
119 * inspired by Mark Andrews.
120 * author:
121 * Paul Vixie, 1996.
122 */
123 static int
inet_pton6(const char * src,u_char * dst)124 inet_pton6(const char *src, u_char *dst)
125 {
126 static const char xdigits_l[] = "0123456789abcdef",
127 xdigits_u[] = "0123456789ABCDEF";
128 u_char tmp[IN6ADDRSZ], *tp, *endp, *colonp;
129 const char *xdigits, *curtok;
130 int ch, saw_xdigit, count_xdigit;
131 u_int val;
132
133 memset((tp = tmp), '\0', IN6ADDRSZ);
134 endp = tp + IN6ADDRSZ;
135 colonp = NULL;
136 /* Leading :: requires some special handling. */
137 if (*src == ':')
138 if (*++src != ':')
139 return (0);
140 curtok = src;
141 saw_xdigit = count_xdigit = 0;
142 val = 0;
143 while ((ch = *src++) != '\0') {
144 const char *pch;
145
146 if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
147 pch = strchr((xdigits = xdigits_u), ch);
148 if (pch != NULL) {
149 if (count_xdigit >= 4)
150 return (0);
151 val <<= 4;
152 val |= (pch - xdigits);
153 if (val > 0xffff)
154 return (0);
155 saw_xdigit = 1;
156 count_xdigit++;
157 continue;
158 }
159 if (ch == ':') {
160 curtok = src;
161 if (!saw_xdigit) {
162 if (colonp)
163 return (0);
164 colonp = tp;
165 continue;
166 } else if (*src == '\0') {
167 return (0);
168 }
169 if (tp + INT16SZ > endp)
170 return (0);
171 *tp++ = (u_char) (val >> 8) & 0xff;
172 *tp++ = (u_char) val & 0xff;
173 saw_xdigit = 0;
174 count_xdigit = 0;
175 val = 0;
176 continue;
177 }
178 if (ch == '.' && ((tp + INADDRSZ) <= endp) &&
179 inet_pton4(curtok, tp) > 0) {
180 tp += INADDRSZ;
181 saw_xdigit = 0;
182 count_xdigit = 0;
183 break; /* '\0' was seen by inet_pton4(). */
184 }
185 return (0);
186 }
187 if (saw_xdigit) {
188 if (tp + INT16SZ > endp)
189 return (0);
190 *tp++ = (u_char) (val >> 8) & 0xff;
191 *tp++ = (u_char) val & 0xff;
192 }
193 if (colonp != NULL) {
194 /*
195 * Since some memmove()'s erroneously fail to handle
196 * overlapping regions, we'll do the shift by hand.
197 */
198 const int n = tp - colonp;
199 int i;
200
201 if (tp == endp)
202 return (0);
203 for (i = 1; i <= n; i++) {
204 endp[- i] = colonp[n - i];
205 colonp[n - i] = 0;
206 }
207 tp = endp;
208 }
209 if (tp != endp)
210 return (0);
211 memcpy(dst, tmp, IN6ADDRSZ);
212 return (1);
213 }
214