xref: /minix/external/bsd/bind/dist/lib/isc/netaddr.c (revision fb9c64b2) 
1 /*	$NetBSD: netaddr.c,v 1.6 2014/12/10 04:37:59 christos Exp $	*/
2 
3 /*
4  * Copyright (C) 2004, 2005, 2007, 2010-2012, 2014  Internet Systems Consortium, Inc. ("ISC")
5  * Copyright (C) 1999-2002  Internet Software Consortium.
6  *
7  * Permission to use, copy, modify, and/or 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 WITH
12  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
13  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
14  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
15  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
16  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
17  * PERFORMANCE OF THIS SOFTWARE.
18  */
19 
20 /* Id */
21 
22 /*! \file */
23 
24 #include <config.h>
25 
26 #include <stdio.h>
27 
28 #include <isc/buffer.h>
29 #include <isc/msgs.h>
30 #include <isc/net.h>
31 #include <isc/netaddr.h>
32 #include <isc/print.h>
33 #include <isc/sockaddr.h>
34 #include <isc/string.h>
35 #include <isc/util.h>
36 
37 isc_boolean_t
38 isc_netaddr_equal(const isc_netaddr_t *a, const isc_netaddr_t *b) {
39 	REQUIRE(a != NULL && b != NULL);
40 
41 	if (a->family != b->family)
42 		return (ISC_FALSE);
43 
44 	if (a->zone != b->zone)
45 		return (ISC_FALSE);
46 
47 	switch (a->family) {
48 	case AF_INET:
49 		if (a->type.in.s_addr != b->type.in.s_addr)
50 			return (ISC_FALSE);
51 		break;
52 	case AF_INET6:
53 		if (memcmp(&a->type.in6, &b->type.in6,
54 			   sizeof(a->type.in6)) != 0 ||
55 		    a->zone != b->zone)
56 			return (ISC_FALSE);
57 		break;
58 #ifdef ISC_PLATFORM_HAVESYSUNH
59 	case AF_UNIX:
60 		if (strcmp(a->type.un, b->type.un) != 0)
61 			return (ISC_FALSE);
62 		break;
63 #endif
64 	default:
65 		return (ISC_FALSE);
66 	}
67 	return (ISC_TRUE);
68 }
69 
70 isc_boolean_t
71 isc_netaddr_eqprefix(const isc_netaddr_t *a, const isc_netaddr_t *b,
72 		     unsigned int prefixlen)
73 {
74 	const unsigned char *pa = NULL, *pb = NULL;
75 	unsigned int ipabytes = 0; /* Length of whole IP address in bytes */
76 	unsigned int nbytes;       /* Number of significant whole bytes */
77 	unsigned int nbits;        /* Number of significant leftover bits */
78 
79 	REQUIRE(a != NULL && b != NULL);
80 
81 	if (a->family != b->family)
82 		return (ISC_FALSE);
83 
84 	if (a->zone != b->zone && b->zone != 0)
85 		return (ISC_FALSE);
86 
87 	switch (a->family) {
88 	case AF_INET:
89 		pa = (const unsigned char *) &a->type.in;
90 		pb = (const unsigned char *) &b->type.in;
91 		ipabytes = 4;
92 		break;
93 	case AF_INET6:
94 		pa = (const unsigned char *) &a->type.in6;
95 		pb = (const unsigned char *) &b->type.in6;
96 		ipabytes = 16;
97 		break;
98 	default:
99 		return (ISC_FALSE);
100 	}
101 
102 	/*
103 	 * Don't crash if we get a pattern like 10.0.0.1/9999999.
104 	 */
105 	if (prefixlen > ipabytes * 8)
106 		prefixlen = ipabytes * 8;
107 
108 	nbytes = prefixlen / 8;
109 	nbits = prefixlen % 8;
110 
111 	if (nbytes > 0) {
112 		if (memcmp(pa, pb, nbytes) != 0)
113 			return (ISC_FALSE);
114 	}
115 	if (nbits > 0) {
116 		unsigned int bytea, byteb, mask;
117 		INSIST(nbytes < ipabytes);
118 		INSIST(nbits < 8);
119 		bytea = pa[nbytes];
120 		byteb = pb[nbytes];
121 		mask = (0xFF << (8-nbits)) & 0xFF;
122 		if ((bytea & mask) != (byteb & mask))
123 			return (ISC_FALSE);
124 	}
125 	return (ISC_TRUE);
126 }
127 
128 isc_result_t
129 isc_netaddr_totext(const isc_netaddr_t *netaddr, isc_buffer_t *target) {
130 	char abuf[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
131 	char zbuf[sizeof("%4294967295")];
132 	unsigned int alen;
133 	int zlen;
134 	const char *r;
135 	const void *type;
136 
137 	REQUIRE(netaddr != NULL);
138 
139 	switch (netaddr->family) {
140 	case AF_INET:
141 		type = &netaddr->type.in;
142 		break;
143 	case AF_INET6:
144 		type = &netaddr->type.in6;
145 		break;
146 #ifdef ISC_PLATFORM_HAVESYSUNH
147 	case AF_UNIX:
148 		alen = strlen(netaddr->type.un);
149 		if (alen > isc_buffer_availablelength(target))
150 			return (ISC_R_NOSPACE);
151 		isc_buffer_putmem(target,
152 				  (const unsigned char *)(netaddr->type.un),
153 				  alen);
154 		return (ISC_R_SUCCESS);
155 #endif
156 	default:
157 		return (ISC_R_FAILURE);
158 	}
159 	r = inet_ntop(netaddr->family, type, abuf, sizeof(abuf));
160 	if (r == NULL)
161 		return (ISC_R_FAILURE);
162 
163 	alen = strlen(abuf);
164 	INSIST(alen < sizeof(abuf));
165 
166 	zlen = 0;
167 	if (netaddr->family == AF_INET6 && netaddr->zone != 0) {
168 		zlen = snprintf(zbuf, sizeof(zbuf), "%%%u", netaddr->zone);
169 		if (zlen < 0)
170 			return (ISC_R_FAILURE);
171 		INSIST((unsigned int)zlen < sizeof(zbuf));
172 	}
173 
174 	if (alen + zlen > isc_buffer_availablelength(target))
175 		return (ISC_R_NOSPACE);
176 
177 	isc_buffer_putmem(target, (unsigned char *)abuf, alen);
178 	isc_buffer_putmem(target, (unsigned char *)zbuf, zlen);
179 
180 	return (ISC_R_SUCCESS);
181 }
182 
183 void
184 isc_netaddr_format(const isc_netaddr_t *na, char *array, unsigned int size) {
185 	isc_result_t result;
186 	isc_buffer_t buf;
187 
188 	isc_buffer_init(&buf, array, size);
189 	result = isc_netaddr_totext(na, &buf);
190 
191 	if (size == 0)
192 		return;
193 
194 	/*
195 	 * Null terminate.
196 	 */
197 	if (result == ISC_R_SUCCESS) {
198 		if (isc_buffer_availablelength(&buf) >= 1)
199 			isc_buffer_putuint8(&buf, 0);
200 		else
201 			result = ISC_R_NOSPACE;
202 	}
203 
204 	if (result != ISC_R_SUCCESS) {
205 		snprintf(array, size,
206 			 isc_msgcat_get(isc_msgcat, ISC_MSGSET_NETADDR,
207 					ISC_MSG_UNKNOWNADDR,
208 					"<unknown address, family %u>"),
209 			 na->family);
210 		array[size - 1] = '\0';
211 	}
212 }
213 
214 
215 isc_result_t
216 isc_netaddr_prefixok(const isc_netaddr_t *na, unsigned int prefixlen) {
217 	static const unsigned char zeros[16];
218 	unsigned int nbits, nbytes, ipbytes = 0;
219 	const unsigned char *p;
220 
221 	switch (na->family) {
222 	case AF_INET:
223 		p = (const unsigned char *) &na->type.in;
224 		ipbytes = 4;
225 		if (prefixlen > 32)
226 			return (ISC_R_RANGE);
227 		break;
228 	case AF_INET6:
229 		p = (const unsigned char *) &na->type.in6;
230 		ipbytes = 16;
231 		if (prefixlen > 128)
232 			return (ISC_R_RANGE);
233 		break;
234 	default:
235 		return (ISC_R_NOTIMPLEMENTED);
236 	}
237 	nbytes = prefixlen / 8;
238 	nbits = prefixlen % 8;
239 	if (nbits != 0) {
240 		INSIST(nbytes < ipbytes);
241 		if ((p[nbytes] & (0xff>>nbits)) != 0U)
242 			return (ISC_R_FAILURE);
243 		nbytes++;
244 	}
245 	if (nbytes < ipbytes && memcmp(p + nbytes, zeros, ipbytes - nbytes) != 0)
246 		return (ISC_R_FAILURE);
247 	return (ISC_R_SUCCESS);
248 }
249 
250 isc_result_t
251 isc_netaddr_masktoprefixlen(const isc_netaddr_t *s, unsigned int *lenp) {
252 	unsigned int nbits = 0, nbytes = 0, ipbytes = 0, i;
253 	const unsigned char *p;
254 
255 	switch (s->family) {
256 	case AF_INET:
257 		p = (const unsigned char *) &s->type.in;
258 		ipbytes = 4;
259 		break;
260 	case AF_INET6:
261 		p = (const unsigned char *) &s->type.in6;
262 		ipbytes = 16;
263 		break;
264 	default:
265 		return (ISC_R_NOTIMPLEMENTED);
266 	}
267 	for (i = 0; i < ipbytes; i++) {
268 		if (p[i] != 0xFF)
269 			break;
270 	}
271 	nbytes = i;
272 	if (i < ipbytes) {
273 		unsigned int c = p[nbytes];
274 		while ((c & 0x80) != 0 && nbits < 8) {
275 			c <<= 1; nbits++;
276 		}
277 		if ((c & 0xFF) != 0)
278 			return (ISC_R_MASKNONCONTIG);
279 		i++;
280 	}
281 	for (; i < ipbytes; i++) {
282 		if (p[i] != 0)
283 			return (ISC_R_MASKNONCONTIG);
284 		i++;
285 	}
286 	*lenp = nbytes * 8 + nbits;
287 	return (ISC_R_SUCCESS);
288 }
289 
290 void
291 isc_netaddr_fromin(isc_netaddr_t *netaddr, const struct in_addr *ina) {
292 	memset(netaddr, 0, sizeof(*netaddr));
293 	netaddr->family = AF_INET;
294 	netaddr->type.in = *ina;
295 }
296 
297 void
298 isc_netaddr_fromin6(isc_netaddr_t *netaddr, const struct in6_addr *ina6) {
299 	memset(netaddr, 0, sizeof(*netaddr));
300 	netaddr->family = AF_INET6;
301 	netaddr->type.in6 = *ina6;
302 }
303 
304 isc_result_t
305 isc_netaddr_frompath(isc_netaddr_t *netaddr, const char *path) {
306 #ifdef ISC_PLATFORM_HAVESYSUNH
307 	if (strlen(path) > sizeof(netaddr->type.un) - 1)
308 		return (ISC_R_NOSPACE);
309 
310 	memset(netaddr, 0, sizeof(*netaddr));
311 	netaddr->family = AF_UNIX;
312 	strcpy(netaddr->type.un, path);
313 	netaddr->zone = 0;
314 	return (ISC_R_SUCCESS);
315 #else
316 	UNUSED(netaddr);
317 	UNUSED(path);
318 	return (ISC_R_NOTIMPLEMENTED);
319 #endif
320 }
321 
322 
323 void
324 isc_netaddr_setzone(isc_netaddr_t *netaddr, isc_uint32_t zone) {
325 	/* we currently only support AF_INET6. */
326 	REQUIRE(netaddr->family == AF_INET6);
327 
328 	netaddr->zone = zone;
329 }
330 
331 isc_uint32_t
332 isc_netaddr_getzone(const isc_netaddr_t *netaddr) {
333 	return (netaddr->zone);
334 }
335 
336 void
337 isc_netaddr_fromsockaddr(isc_netaddr_t *t, const isc_sockaddr_t *s) {
338 	int family = s->type.sa.sa_family;
339 	t->family = family;
340 	switch (family) {
341 	case AF_INET:
342 		t->type.in = s->type.sin.sin_addr;
343 		t->zone = 0;
344 		break;
345 	case AF_INET6:
346 		memmove(&t->type.in6, &s->type.sin6.sin6_addr, 16);
347 #ifdef ISC_PLATFORM_HAVESCOPEID
348 		t->zone = s->type.sin6.sin6_scope_id;
349 #else
350 		t->zone = 0;
351 #endif
352 		break;
353 #ifdef ISC_PLATFORM_HAVESYSUNH
354 	case AF_UNIX:
355 		memmove(t->type.un, s->type.sunix.sun_path, sizeof(t->type.un));
356 		t->zone = 0;
357 		break;
358 #endif
359 	default:
360 		INSIST(0);
361 	}
362 }
363 
364 void
365 isc_netaddr_any(isc_netaddr_t *netaddr) {
366 	memset(netaddr, 0, sizeof(*netaddr));
367 	netaddr->family = AF_INET;
368 	netaddr->type.in.s_addr = INADDR_ANY;
369 }
370 
371 void
372 isc_netaddr_any6(isc_netaddr_t *netaddr) {
373 	memset(netaddr, 0, sizeof(*netaddr));
374 	netaddr->family = AF_INET6;
375 	netaddr->type.in6 = in6addr_any;
376 }
377 
378 isc_boolean_t
379 isc_netaddr_ismulticast(isc_netaddr_t *na) {
380 	switch (na->family) {
381 	case AF_INET:
382 		return (ISC_TF(ISC_IPADDR_ISMULTICAST(na->type.in.s_addr)));
383 	case AF_INET6:
384 		return (ISC_TF(IN6_IS_ADDR_MULTICAST(&na->type.in6)));
385 	default:
386 		return (ISC_FALSE);  /* XXXMLG ? */
387 	}
388 }
389 
390 isc_boolean_t
391 isc_netaddr_isexperimental(isc_netaddr_t *na) {
392 	switch (na->family) {
393 	case AF_INET:
394 		return (ISC_TF(ISC_IPADDR_ISEXPERIMENTAL(na->type.in.s_addr)));
395 	default:
396 		return (ISC_FALSE);  /* XXXMLG ? */
397 	}
398 }
399 
400 isc_boolean_t
401 isc_netaddr_islinklocal(isc_netaddr_t *na) {
402 	switch (na->family) {
403 	case AF_INET:
404 		return (ISC_FALSE);
405 	case AF_INET6:
406 		return (ISC_TF(IN6_IS_ADDR_LINKLOCAL(&na->type.in6)));
407 	default:
408 		return (ISC_FALSE);
409 	}
410 }
411 
412 isc_boolean_t
413 isc_netaddr_issitelocal(isc_netaddr_t *na) {
414 	switch (na->family) {
415 	case AF_INET:
416 		return (ISC_FALSE);
417 	case AF_INET6:
418 		return (ISC_TF(IN6_IS_ADDR_SITELOCAL(&na->type.in6)));
419 	default:
420 		return (ISC_FALSE);
421 	}
422 }
423 
424 void
425 isc_netaddr_fromv4mapped(isc_netaddr_t *t, const isc_netaddr_t *s) {
426 	isc_netaddr_t *src;
427 
428 	DE_CONST(s, src);	/* Must come before IN6_IS_ADDR_V4MAPPED. */
429 
430 	REQUIRE(s->family == AF_INET6);
431 	REQUIRE(IN6_IS_ADDR_V4MAPPED(&src->type.in6));
432 
433 	memset(t, 0, sizeof(*t));
434 	t->family = AF_INET;
435 	memmove(&t->type.in, (char *)&src->type.in6 + 12, 4);
436 	return;
437 }
438