1 /* $NetBSD: inet_pton.c,v 1.8 2012/03/13 21:13:38 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 #include <sys/cdefs.h>
21 #if defined(LIBC_SCCS) && !defined(lint)
22 #if 0
23 static const char rcsid[] = "Id: inet_pton.c,v 1.5 2005/07/28 06:51:47 marka Exp";
24 #else
25 __RCSID("$NetBSD: inet_pton.c,v 1.8 2012/03/13 21:13:38 christos Exp $");
26 #endif
27 #endif /* LIBC_SCCS and not lint */
28
29 #include "port_before.h"
30
31 #include "namespace.h"
32 #include <sys/param.h>
33 #include <sys/types.h>
34 #include <sys/socket.h>
35 #include <netinet/in.h>
36 #include <arpa/inet.h>
37 #include <arpa/nameser.h>
38 #include <stddef.h>
39 #include <string.h>
40 #include <assert.h>
41 #include <ctype.h>
42 #include <errno.h>
43
44 #include "port_after.h"
45
46 #ifdef __weak_alias
47 __weak_alias(inet_pton,_inet_pton)
48 #endif
49
50 /*%
51 * WARNING: Don't even consider trying to compile this on a system where
52 * sizeof(int) < 4. sizeof(int) > 4 is fine; all the world's not a VAX.
53 */
54
55 static int inet_pton4(const char *src, u_char *dst, int pton);
56 static int inet_pton6(const char *src, u_char *dst);
57
58 /* int
59 * inet_pton(af, src, dst)
60 * convert from presentation format (which usually means ASCII printable)
61 * to network format (which is usually some kind of binary format).
62 * return:
63 * 1 if the address was valid for the specified address family
64 * 0 if the address wasn't valid (`dst' is untouched in this case)
65 * -1 if some other error occurred (`dst' is untouched in this case, too)
66 * author:
67 * Paul Vixie, 1996.
68 */
69 int
inet_pton(int af,const char * src,void * dst)70 inet_pton(int af, const char *src, void *dst)
71 {
72
73 _DIAGASSERT(src != NULL);
74 _DIAGASSERT(dst != NULL);
75
76 switch (af) {
77 case AF_INET:
78 return (inet_pton4(src, dst, 1));
79 case AF_INET6:
80 return (inet_pton6(src, dst));
81 default:
82 errno = EAFNOSUPPORT;
83 return (-1);
84 }
85 /* NOTREACHED */
86 }
87
88 /* int
89 * inet_pton4(src, dst, pton)
90 * when last arg is 0: inet_aton(). with hexadecimal, octal and shorthand.
91 * when last arg is 1: inet_pton(). decimal dotted-quad only.
92 * return:
93 * 1 if `src' is a valid input, else 0.
94 * notice:
95 * does not touch `dst' unless it's returning 1.
96 * author:
97 * Paul Vixie, 1996.
98 */
99 static int
inet_pton4(const char * src,u_char * dst,int pton)100 inet_pton4(const char *src, u_char *dst, int pton)
101 {
102 u_int32_t val;
103 u_int digit, base;
104 ptrdiff_t n;
105 unsigned char c;
106 u_int parts[4];
107 u_int *pp = parts;
108
109 _DIAGASSERT(src != NULL);
110 _DIAGASSERT(dst != NULL);
111
112 c = *src;
113 for (;;) {
114 /*
115 * Collect number up to ``.''.
116 * Values are specified as for C:
117 * 0x=hex, 0=octal, isdigit=decimal.
118 */
119 if (!isdigit(c))
120 return (0);
121 val = 0; base = 10;
122 if (c == '0') {
123 c = *++src;
124 if (c == 'x' || c == 'X')
125 base = 16, c = *++src;
126 else if (isdigit(c) && c != '9')
127 base = 8;
128 }
129 /* inet_pton() takes decimal only */
130 if (pton && base != 10)
131 return (0);
132 for (;;) {
133 if (isdigit(c)) {
134 digit = c - '0';
135 if (digit >= base)
136 break;
137 val = (val * base) + digit;
138 c = *++src;
139 } else if (base == 16 && isxdigit(c)) {
140 digit = c + 10 - (islower(c) ? 'a' : 'A');
141 if (digit >= 16)
142 break;
143 val = (val << 4) | digit;
144 c = *++src;
145 } else
146 break;
147 }
148 if (c == '.') {
149 /*
150 * Internet format:
151 * a.b.c.d
152 * a.b.c (with c treated as 16 bits)
153 * a.b (with b treated as 24 bits)
154 * a (with a treated as 32 bits)
155 */
156 if (pp >= parts + 3)
157 return (0);
158 *pp++ = val;
159 c = *++src;
160 } else
161 break;
162 }
163 /*
164 * Check for trailing characters.
165 */
166 if (c != '\0' && !isspace(c))
167 return (0);
168 /*
169 * Concoct the address according to
170 * the number of parts specified.
171 */
172 n = pp - parts + 1;
173 /* inet_pton() takes dotted-quad only. it does not take shorthand. */
174 if (pton && n != 4)
175 return (0);
176 switch (n) {
177
178 case 0:
179 return (0); /* initial nondigit */
180
181 case 1: /* a -- 32 bits */
182 break;
183
184 case 2: /* a.b -- 8.24 bits */
185 if (parts[0] > 0xff || val > 0xffffff)
186 return (0);
187 val |= parts[0] << 24;
188 break;
189
190 case 3: /* a.b.c -- 8.8.16 bits */
191 if ((parts[0] | parts[1]) > 0xff || val > 0xffff)
192 return (0);
193 val |= (parts[0] << 24) | (parts[1] << 16);
194 break;
195
196 case 4: /* a.b.c.d -- 8.8.8.8 bits */
197 if ((parts[0] | parts[1] | parts[2] | val) > 0xff)
198 return (0);
199 val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
200 break;
201 }
202 if (dst) {
203 val = htonl(val);
204 memcpy(dst, &val, NS_INADDRSZ);
205 }
206 return (1);
207 }
208
209 /* int
210 * inet_pton6(src, dst)
211 * convert presentation level address to network order binary form.
212 * return:
213 * 1 if `src' is a valid [RFC1884 2.2] address, else 0.
214 * notice:
215 * (1) does not touch `dst' unless it's returning 1.
216 * (2) :: in a full address is silently ignored.
217 * credit:
218 * inspired by Mark Andrews.
219 * author:
220 * Paul Vixie, 1996.
221 */
222 static int
inet_pton6(const char * src,u_char * dst)223 inet_pton6(const char *src, u_char *dst)
224 {
225 static const char xdigits_l[] = "0123456789abcdef",
226 xdigits_u[] = "0123456789ABCDEF";
227 u_char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
228 const char *xdigits, *curtok;
229 int ch, seen_xdigits;
230 u_int val;
231
232 _DIAGASSERT(src != NULL);
233 _DIAGASSERT(dst != NULL);
234
235 memset((tp = tmp), '\0', NS_IN6ADDRSZ);
236 endp = tp + NS_IN6ADDRSZ;
237 colonp = NULL;
238 /* Leading :: requires some special handling. */
239 if (*src == ':')
240 if (*++src != ':')
241 return (0);
242 curtok = src;
243 seen_xdigits = 0;
244 val = 0;
245 while ((ch = *src++) != '\0') {
246 const char *pch;
247
248 if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
249 pch = strchr((xdigits = xdigits_u), ch);
250 if (pch != NULL) {
251 val <<= 4;
252 val |= (int)(pch - xdigits);
253 if (++seen_xdigits > 4)
254 return (0);
255 continue;
256 }
257 if (ch == ':') {
258 curtok = src;
259 if (!seen_xdigits) {
260 if (colonp)
261 return (0);
262 colonp = tp;
263 continue;
264 } else if (*src == '\0')
265 return (0);
266 if (tp + NS_INT16SZ > endp)
267 return (0);
268 *tp++ = (u_char) (val >> 8) & 0xff;
269 *tp++ = (u_char) val & 0xff;
270 seen_xdigits = 0;
271 val = 0;
272 continue;
273 }
274 if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
275 inet_pton4(curtok, tp, 1) > 0) {
276 tp += NS_INADDRSZ;
277 seen_xdigits = 0;
278 break; /*%< '\\0' was seen by inet_pton4(). */
279 }
280 return (0);
281 }
282 if (seen_xdigits) {
283 if (tp + NS_INT16SZ > endp)
284 return (0);
285 *tp++ = (u_char) (val >> 8) & 0xff;
286 *tp++ = (u_char) val & 0xff;
287 }
288 if (colonp != NULL) {
289 /*
290 * Since some memmove()'s erroneously fail to handle
291 * overlapping regions, we'll do the shift by hand.
292 */
293 const ptrdiff_t n = tp - colonp;
294 int i;
295
296 if (tp == endp)
297 return (0);
298 for (i = 1; i <= n; i++) {
299 endp[- i] = colonp[n - i];
300 colonp[n - i] = 0;
301 }
302 tp = endp;
303 }
304 if (tp != endp)
305 return (0);
306 memcpy(dst, tmp, NS_IN6ADDRSZ);
307 return (1);
308 }
309
310 /*! \file */
311