1 /*
2 * Copyright (c) 1996,1999 by Internet Software Consortium.
3 *
4 * Permission to use, copy, modify, and distribute this software for any
5 * purpose with or without fee is hereby granted, provided that the above
6 * copyright notice and this permission notice appear in all copies.
7 *
8 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
9 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
10 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
11 * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
12 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
13 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
14 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
15 * SOFTWARE.
16 */
17
18 #include <sys/cdefs.h>
19 #if defined(LIBC_SCCS) && !defined(lint)
20 #if 0
21 static const char rcsid[] = "Id: inet_net_pton.c,v 1.4.2.1 2002/08/02 02:17:21 marka Exp ";
22 #else
23 __RCSID("$NetBSD: inet_net_pton.c,v 1.7 2024/05/12 23:58:18 msaitoh Exp $");
24 #endif
25 #endif
26
27 #include "port_before.h"
28
29 #include "namespace.h"
30 #include <sys/types.h>
31 #include <sys/socket.h>
32 #include <netinet/in.h>
33 #include <arpa/nameser.h>
34 #include <arpa/inet.h>
35
36 #include <isc/assertions.h>
37 #include <stddef.h>
38 #include <ctype.h>
39 #include <errno.h>
40 #include <stdio.h>
41 #include <string.h>
42 #include <stdlib.h>
43
44 #include "port_after.h"
45
46 #ifdef __weak_alias
__weak_alias(inet_net_pton,_inet_net_pton)47 __weak_alias(inet_net_pton,_inet_net_pton)
48 #endif
49
50 /*
51 * static int
52 * inet_net_pton_ipv4(src, dst, size)
53 * convert IPv4 network number from presentation to network format.
54 * accepts hex octets, hex strings, decimal octets, and /CIDR.
55 * "size" is in bytes and describes "dst".
56 * return:
57 * number of bits, either inputed classfully or specified with /CIDR,
58 * or -1 if some failure occurred (check errno). ENOENT means it was
59 * not an IPv4 network specification.
60 * note:
61 * network byte order assumed. this means 192.5.5.240/28 has
62 * 0b11110000 in its fourth octet.
63 * author:
64 * Paul Vixie (ISC), June 1996
65 */
66 static int
67 inet_net_pton_ipv4(const char *src, u_char *dst, size_t size)
68 {
69 static const char xdigits[] = "0123456789abcdef";
70 static const char digits[] = "0123456789";
71 int ch, dirty, bits;
72 ptrdiff_t n, tmp;
73 const u_char *odst = dst;
74
75 tmp = 0;
76 ch = *src++;
77 if (ch == '0' && (src[0] == 'x' || src[0] == 'X')
78 && isascii((u_char)(src[1]))
79 && isxdigit((u_char)(src[1]))) {
80 /* Hexadecimal: Eat nybble string. */
81 if (size == 0)
82 goto emsgsize;
83 dirty = 0;
84 src++; /* skip x or X. */
85 while ((ch = *src++) != '\0' && isascii((u_char)ch)
86 && isxdigit((u_char)ch)) {
87 if (isupper((u_char)ch))
88 ch = tolower((u_char)ch);
89 n = strchr(xdigits, ch) - xdigits;
90 INSIST(n >= 0 && n <= 15);
91 if (dirty == 0)
92 tmp = n;
93 else
94 tmp = (tmp << 4) | n;
95 if (++dirty == 2) {
96 if (size-- == 0)
97 goto emsgsize;
98 *dst++ = (u_char) tmp;
99 dirty = 0;
100 }
101 }
102 if (dirty) { /* Odd trailing nybble? */
103 if (size-- == 0)
104 goto emsgsize;
105 *dst++ = (u_char) (tmp << 4);
106 }
107 } else if (isascii((u_char)ch) && isdigit((u_char)ch)) {
108 /* Decimal: eat dotted digit string. */
109 for (;;) {
110 tmp = 0;
111 do {
112 n = strchr(digits, ch) - digits;
113 INSIST(n >= 0 && n <= 9);
114 tmp *= 10;
115 tmp += n;
116 if (tmp > 255)
117 goto enoent;
118 } while ((ch = *src++) != '\0' &&
119 isascii((u_char)ch) && isdigit((u_char)ch));
120 if (size-- == 0)
121 goto emsgsize;
122 *dst++ = (u_char) tmp;
123 if (ch == '\0' || ch == '/')
124 break;
125 if (ch != '.')
126 goto enoent;
127 ch = *src++;
128 if (!isascii((u_char)ch) || !isdigit((u_char)ch))
129 goto enoent;
130 }
131 } else
132 goto enoent;
133
134 bits = -1;
135 if (ch == '/' && isascii((u_char)(src[0])) &&
136 isdigit((u_char)(src[0])) && dst > odst) {
137 /* CIDR width specifier. Nothing can follow it. */
138 ch = *src++; /* Skip over the /. */
139 bits = 0;
140 do {
141 n = strchr(digits, ch) - digits;
142 INSIST(n >= 0 && n <= 9);
143 bits *= 10;
144 bits += (int)n;
145 if (bits > 32)
146 goto emsgsize;
147 } while ((ch = *src++) != '\0' && isascii((u_char)ch)
148 && isdigit((u_char)ch));
149 if (ch != '\0')
150 goto enoent;
151 }
152
153 /* Fiery death and destruction unless we prefetched EOS. */
154 if (ch != '\0')
155 goto enoent;
156
157 /* If nothing was written to the destination, we found no address. */
158 if (dst == odst)
159 goto enoent;
160 /* If no CIDR spec was given, infer width from net class. */
161 if (bits == -1) {
162 if (*odst >= 240) /* Class E */
163 bits = 32;
164 else if (*odst >= 224) /* Class D */
165 bits = 4;
166 else if (*odst >= 192) /* Class C */
167 bits = 24;
168 else if (*odst >= 128) /* Class B */
169 bits = 16;
170 else /* Class A */
171 bits = 8;
172 /* If inputed mask is narrower than specified octets, widen. */
173 if (bits >= 8 && bits < ((dst - odst) * 8))
174 bits = (int)(dst - odst) * 8;
175 }
176 /* Extend network to cover the actual mask. */
177 while (bits > ((dst - odst) * 8)) {
178 if (size-- == 0)
179 goto emsgsize;
180 *dst++ = '\0';
181 }
182 return (bits);
183
184 enoent:
185 errno = ENOENT;
186 return (-1);
187
188 emsgsize:
189 errno = EMSGSIZE;
190 return (-1);
191 }
192
193 static int
getbits(const char * src,int * bitsp)194 getbits(const char *src, int *bitsp)
195 {
196 static const char digits[] = "0123456789";
197 int n;
198 int val;
199 char ch;
200
201 val = 0;
202 n = 0;
203 while ((ch = *src++) != '\0') {
204 const char *pch;
205
206 pch = strchr(digits, ch);
207 if (pch != NULL) {
208 if (n++ != 0 && val == 0) /* no leading zeros */
209 return (0);
210 val *= 10;
211 val += (int)(pch - digits);
212 if (val > 128) /* range */
213 return (0);
214 continue;
215 }
216 return (0);
217 }
218 if (n == 0)
219 return (0);
220 *bitsp = val;
221 return (1);
222 }
223
224 static int
getv4(const char * src,u_char * dst,int * bitsp)225 getv4(const char *src, u_char *dst, int *bitsp)
226 {
227 static const char digits[] = "0123456789";
228 u_char *odst = dst;
229 int n;
230 u_int val;
231 char ch;
232
233 val = 0;
234 n = 0;
235 while ((ch = *src++) != '\0') {
236 const char *pch;
237
238 pch = strchr(digits, ch);
239 if (pch != NULL) {
240 if (n++ != 0 && val == 0) /* no leading zeros */
241 return (0);
242 val *= 10;
243 val += (int)(pch - digits);
244 if (val > 255) /* range */
245 return (0);
246 continue;
247 }
248 if (ch == '.' || ch == '/') {
249 if (dst - odst > 3) /* too many octets? */
250 return (0);
251 *dst++ = val;
252 if (ch == '/')
253 return (getbits(src, bitsp));
254 val = 0;
255 n = 0;
256 continue;
257 }
258 return (0);
259 }
260 if (n == 0)
261 return (0);
262 if (dst - odst > 3) /* too many octets? */
263 return (0);
264 *dst++ = val;
265 return (1);
266 }
267
268 static int
inet_net_pton_ipv6(const char * src,u_char * dst,size_t size)269 inet_net_pton_ipv6(const char *src, u_char *dst, size_t size)
270 {
271 static const char xdigits_l[] = "0123456789abcdef",
272 xdigits_u[] = "0123456789ABCDEF";
273 u_char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
274 const char *xdigits, *curtok;
275 int ch, saw_xdigit;
276 u_int val;
277 int digits;
278 int bits;
279 size_t bytes;
280 int words;
281 int ipv4;
282
283 memset((tp = tmp), '\0', NS_IN6ADDRSZ);
284 endp = tp + NS_IN6ADDRSZ;
285 colonp = NULL;
286 /* Leading :: requires some special handling. */
287 if (*src == ':')
288 if (*++src != ':')
289 goto enoent;
290 curtok = src;
291 saw_xdigit = 0;
292 val = 0;
293 digits = 0;
294 bits = -1;
295 ipv4 = 0;
296 while ((ch = *src++) != '\0') {
297 const char *pch;
298
299 if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
300 pch = strchr((xdigits = xdigits_u), ch);
301 if (pch != NULL) {
302 val <<= 4;
303 val |= (int)(pch - xdigits);
304 if (++digits > 4)
305 goto enoent;
306 saw_xdigit = 1;
307 continue;
308 }
309 if (ch == ':') {
310 curtok = src;
311 if (!saw_xdigit) {
312 if (colonp)
313 goto enoent;
314 colonp = tp;
315 continue;
316 } else if (*src == '\0')
317 goto enoent;
318 if (tp + NS_INT16SZ > endp)
319 return (0);
320 *tp++ = (u_char) (val >> 8) & 0xff;
321 *tp++ = (u_char) val & 0xff;
322 saw_xdigit = 0;
323 digits = 0;
324 val = 0;
325 continue;
326 }
327 if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
328 getv4(curtok, tp, &bits) > 0) {
329 tp += NS_INADDRSZ;
330 saw_xdigit = 0;
331 ipv4 = 1;
332 break; /* '\0' was seen by inet_pton4(). */
333 }
334 if (ch == '/' && getbits(src, &bits) > 0)
335 break;
336 goto enoent;
337 }
338 if (saw_xdigit) {
339 if (tp + NS_INT16SZ > endp)
340 goto enoent;
341 *tp++ = (u_char) (val >> 8) & 0xff;
342 *tp++ = (u_char) val & 0xff;
343 }
344 if (bits == -1)
345 bits = 128;
346
347 words = (bits + 15) / 16;
348 if (words < 2)
349 words = 2;
350 if (ipv4)
351 words = 8;
352 endp = tmp + 2 * words;
353
354 if (colonp != NULL) {
355 /*
356 * Since some memmove()'s erroneously fail to handle
357 * overlapping regions, we'll do the shift by hand.
358 */
359 const ptrdiff_t n = tp - colonp;
360 int i;
361
362 if (tp == endp)
363 goto enoent;
364 for (i = 1; i <= n; i++) {
365 endp[- i] = colonp[n - i];
366 colonp[n - i] = 0;
367 }
368 tp = endp;
369 }
370 if (tp != endp)
371 goto enoent;
372
373 bytes = (bits + 7) / 8;
374 if (bytes > size)
375 goto emsgsize;
376 memcpy(dst, tmp, bytes);
377 return (bits);
378
379 enoent:
380 errno = ENOENT;
381 return (-1);
382
383 emsgsize:
384 errno = EMSGSIZE;
385 return (-1);
386 }
387
388 /*
389 * int
390 * inet_net_pton(af, src, dst, size)
391 * convert network number from presentation to network format.
392 * accepts hex octets, hex strings, decimal octets, and /CIDR.
393 * "size" is in bytes and describes "dst".
394 * return:
395 * number of bits, either inputed classfully or specified with /CIDR,
396 * or -1 if some failure occurred (check errno). ENOENT means it was
397 * not a valid network specification.
398 * author:
399 * Paul Vixie (ISC), June 1996
400 */
401 int
inet_net_pton(int af,const char * src,void * dst,size_t size)402 inet_net_pton(int af, const char *src, void *dst, size_t size)
403 {
404 switch (af) {
405 case AF_INET:
406 return (inet_net_pton_ipv4(src, dst, size));
407 case AF_INET6:
408 return (inet_net_pton_ipv6(src, dst, size));
409 default:
410 errno = EAFNOSUPPORT;
411 return (-1);
412 }
413 }
414