3 * - address-family specific code
6 * This file is part of adns, which is
7 * Copyright (C) 1997-2000,2003,2006 Ian Jackson
8 * Copyright (C) 1999-2000,2003,2006 Tony Finch
9 * Copyright (C) 1991 Massachusetts Institute of Technology
10 * (See the file INSTALL for full details.)
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2, or (at your option)
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software Foundation,
24 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
35 #include <sys/types.h>
36 #include <sys/socket.h>
37 #include <netinet/in.h>
38 #include <arpa/inet.h>
44 * General address-family operations.
47 #define SIN(cnst, sa) ((void)(sa)->sa_family, (cnst struct sockaddr_in *)(sa))
48 #define SIN6(cnst, sa) ((void)(sa)->sa_family, (cnst struct sockaddr_in6 *)(sa))
50 static void unknown_af(int af) NONRETURNING;
51 static void unknown_af(int af) {
52 fprintf(stderr, "ADNS INTERNAL: unknown address family %d\n", af);
57 * SOCKADDR_IN_IN6(CNST, struct sockaddr *sa, SIN, {
58 * // struct sockaddr_in *const SIN; // implicitly
61 * // struct sockaddr_in6 *const SIN6; // implicitly
65 * SOCKADDR_IN_IN6_PAIR(CNST, struct sockaddr *sa, SINA,
66 * struct sockaddr *sb, SINB, {
67 * // struct sockaddr_in *const SINA; // implicitly
68 * // struct sockaddr_in *const SINB; // implicitly
71 * // struct sockaddr_in6 *const SINA6; // implicitly
72 * // struct sockaddr_in6 *const SINB6; // implicitly
76 * SOCKADDR_IN_IN6_OTHER(CNST, struct sockaddr *sa, SIN, { in }, { in6 }, {
77 * code for other address family
80 * AF_IN_IN6_OTHER(af, { in }, { in6 }, { other })
82 * Executes the first or second block according to the AF in sa. CNST
83 * may be `const' or empty. For _PAIR, sa and sb must be same AF.
85 * All except _OTHER handle unknown AFs with unknown_af.
87 * Code blocks may not contain , outside parens.
89 #define AF_IN_IN6_OTHER(af, for_inet, for_inet6, other) \
90 if ((af) == AF_INET) { \
92 } else if ((af) == AF_INET6) { \
97 #define SOCKADDR_IN_IN6_OTHER(cnst, sa, sin, for_inet, for_inet6, other) \
98 AF_IN_IN6_OTHER((sa)->sa_family, { \
99 cnst struct sockaddr_in *const sin = SIN(cnst,(sa)); \
102 cnst struct sockaddr_in6 *const sin##6 = SIN6(cnst,(sa)); \
107 #define SOCKADDR_IN_IN6(cnst, sa, sin, for_inet, for_inet6) \
108 SOCKADDR_IN_IN6_OTHER(cnst, sa, sin, for_inet, for_inet6, { \
109 unknown_af((sa)->sa_family); \
111 #define SOCKADDR_IN_IN6_PAIR(cnst, sa, sina, sb, sinb, for_inet, for_inet6) \
113 assert((sa)->sa_family == (sb)->sa_family); \
114 SOCKADDR_IN_IN6(cnst, sa, sina, { \
115 cnst struct sockaddr_in *const sinb = SIN(cnst,(sb)); \
118 cnst struct sockaddr_in6 *const sinb##6 = SIN6(cnst,(sb)); \
123 int adns__addrs_equal_raw(const struct sockaddr *a,
124 int bf, const void *b) {
125 if (a->sa_family != bf) return 0;
127 SOCKADDR_IN_IN6(const, a, sin, {
128 return sin->sin_addr.s_addr == ((const struct in_addr*)b)->s_addr;
130 return !memcmp(&sin6->sin6_addr, b, sizeof(struct in6_addr));
134 int adns__addrs_equal(const adns_sockaddr *a, const adns_sockaddr *b) {
135 return adns__addrs_equal_raw(&a->sa, b->sa.sa_family,
136 adns__sockaddr_addr(&b->sa));
139 int adns__sockaddrs_equal(const struct sockaddr *sa,
140 const struct sockaddr *sb) {
141 if (!adns__addrs_equal_raw(sa, sb->sa_family, adns__sockaddr_addr(sb)))
143 SOCKADDR_IN_IN6_PAIR(const, sa, sina, sb, sinb, {
144 return sina->sin_port == sinb->sin_port;
146 return sina6->sin6_port == sinb6->sin6_port &&
147 sina6->sin6_scope_id == sinb6->sin6_scope_id;
151 int adns__addr_width(int af) {
152 AF_IN_IN6_OTHER(af, {
161 void adns__prefix_mask(adns_sockaddr *sa, int len) {
162 SOCKADDR_IN_IN6(, &sa->sa, sin, {
164 sin->sin_addr.s_addr= htonl(!len ? 0 : 0xffffffff << (32-len));
168 unsigned char *m= sin6->sin6_addr.s6_addr;
171 if (j) m[i++]= (0xff << (8-j)) & 0xff;
172 memset(m+i, 0, 16-i);
176 int adns__guess_prefix_length(const adns_sockaddr *sa) {
177 SOCKADDR_IN_IN6(const, &sa->sa, sin, {
178 unsigned a= (ntohl(sin->sin_addr.s_addr) >> 24) & 0xff;
179 if (a < 128) return 8;
180 else if (a < 192) return 16;
181 else if (a < 224) return 24;
189 int adns__addr_matches(int af, const void *addr,
190 const adns_sockaddr *base, const adns_sockaddr *mask)
192 if (af != base->sa.sa_family) return 0;
193 SOCKADDR_IN_IN6_PAIR(const, &base->sa, sbase, &mask->sa, smask, {
194 const struct in_addr *v4 = addr;
195 return (v4->s_addr & smask->sin_addr.s_addr)
196 == sbase->sin_addr.s_addr;
200 const char *b= sbase6->sin6_addr.s6_addr;
201 const char *m= smask6->sin6_addr.s6_addr;
202 for (i = 0; i < 16; i++)
203 if ((a[i] & m[i]) != b[i]) return 0;
208 const void *adns__sockaddr_addr(const struct sockaddr *sa) {
209 SOCKADDR_IN_IN6(const, sa, sin, {
210 return &sin->sin_addr;
212 return &sin6->sin6_addr;
216 void adns__addr_inject(const void *a, adns_sockaddr *sa) {
217 SOCKADDR_IN_IN6( , &sa->sa, sin, {
218 memcpy(&sin->sin_addr, a, sizeof(sin->sin_addr));
220 memcpy(&sin6->sin6_addr, a, sizeof(sin6->sin6_addr));
225 * addr2text and text2addr
228 #define ADDRFAM_DEBUG
230 static void af_debug_func(const char *fmt, ...) {
234 vfprintf(stderr,fmt,al);
238 # define af_debug(fmt,...) \
239 (af_debug_func("%s: " fmt "\n", __func__, __VA_ARGS__))
241 # define af_debug(fmt,...) ((void)("" fmt "", __VA_ARGS__))
244 static bool addrtext_our_errno(int e) {
252 static bool addrtext_scope_use_ifname(const struct sockaddr *sa) {
253 const struct in6_addr *in6= &SIN6(const,sa)->sin6_addr;
255 IN6_IS_ADDR_LINKLOCAL(in6) ||
256 IN6_IS_ADDR_MC_LINKLOCAL(in6);
259 int adns_text2addr(const char *text, uint16_t port, adns_queryflags flags,
260 struct sockaddr *sa, socklen_t *salen_io) {
262 char copybuf[INET6_ADDRSTRLEN];
263 const char *parse=text;
264 const char *scopestr=0;
269 #define INVAL(how) do{ \
270 af_debug("invalid: %s: `%s'", how, text); \
274 #define AFCORE(INETx,SINx,sinx) \
276 dst = &SINx(,sa)->sinx##_addr; \
277 portp = &SINx(,sa)->sinx##_port; \
278 needlen= sizeof(*SINx(,sa));
280 if (!strchr(text, ':')) { /* INET */
282 AFCORE(INET,SIN,sin);
286 AFCORE(INET6,SIN6,sin6);
288 const char *percent= strchr(text, '%');
290 ptrdiff_t lhslen = percent - text;
291 if (lhslen >= INET6_ADDRSTRLEN) INVAL("scoped addr lhs too long");
292 memcpy(copybuf, text, lhslen);
298 af_debug("will parse scoped addr `%s' %% `%s'", parse, scopestr);
305 if (scopestr && (flags & adns_qf_addrlit_scope_forbid))
306 INVAL("scoped addr but _scope_forbid");
308 if (*salen_io < needlen) {
313 memset(sa, 0, needlen);
316 *portp = htons(port);
318 if (af == AF_INET && !(flags & adns_qf_addrlit_ipv4_quadonly)) {
319 /* we have to use inet_aton to deal with non-dotted-quad literals */
320 int r= inet_aton(parse,&SIN(,sa)->sin_addr);
321 if (!r) INVAL("inet_aton rejected");
323 int r= inet_pton(af,parse,dst);
324 if (!r) INVAL("inet_pton rejected");
331 unsigned long scope= strtoul(scopestr,&ep,10);
332 if (errno==ERANGE) INVAL("numeric scope id too large for unsigned long");
335 if (scope > ~(uint32_t)0)
336 INVAL("numeric scope id too large for uint32_t");
338 if (flags & adns_qf_addrlit_scope_numeric)
339 INVAL("non-numeric scope but _scope_numeric");
340 if (!addrtext_scope_use_ifname(sa)) {
341 af_debug("cannot convert non-numeric scope"
342 " in non-link-local addr `%s'", text);
346 scope= if_nametoindex(scopestr);
348 /* RFC3493 says "No errors are defined". It's not clear
349 * whether that is supposed to mean if_nametoindex "can't
350 * fail" (other than by the supplied name not being that of an
351 * interface) which seems unrealistic, or that it conflates
352 * all its errors together by failing to set errno, or simply
353 * that they didn't bother to document the errors.
355 * glibc, FreeBSD and OpenBSD all set errno (to ENXIO when
356 * appropriate). See Debian bug #749349.
358 * We attempt to deal with this by clearing errno to start
359 * with, and then perhaps mapping the results. */
360 af_debug("if_nametoindex rejected scope name (errno=%s)",
364 } else if (addrtext_our_errno(errno)) {
365 /* we use these for other purposes, urgh. */
366 perror("adns: adns_text2addr: if_nametoindex"
367 " failed with unexpected error");
373 if (scope > ~(uint32_t)0) {
374 fprintf(stderr,"adns: adns_text2addr: if_nametoindex"
375 " returned an interface index >=2^32 which will not fit"
376 " in sockaddr_in6.sin6_scope_id");
382 SIN6(,sa)->sin6_scope_id= scope;
383 } /* if (scopestr) */
389 int adns_addr2text(const struct sockaddr *sa, adns_queryflags flags,
390 char *buffer, int *buflen_io, int *port_r) {
394 if (*buflen_io < ADNS_ADDR2TEXT_BUFLEN) {
395 *buflen_io = ADNS_ADDR2TEXT_BUFLEN;
399 SOCKADDR_IN_IN6_OTHER(const, sa, sin, {
400 src= &sin->sin_addr; port= sin->sin_port;
402 src= &sin6->sin6_addr; port= sin6->sin6_port;
407 const char *ok= inet_ntop(sa->sa_family, src, buffer, *buflen_io);
410 if (sa->sa_family == AF_INET6) {
411 uint32_t scope = SIN6(const,sa)->sin6_scope_id;
413 if (flags & adns_qf_addrlit_scope_forbid)
415 int scopeoffset = strlen(buffer);
416 int remain = *buflen_io - scopeoffset;
417 char *scopeptr = buffer + scopeoffset;
418 assert(remain >= IF_NAMESIZE+1/*%*/);
419 *scopeptr++= '%'; remain--;
421 af_debug("will print scoped addr `%.*s' %% %"PRIu32"",
422 scopeoffset,buffer, scope);
423 if (scope <= UINT_MAX /* so we can pass it to if_indextoname */
424 && !(flags & adns_qf_addrlit_scope_numeric)
425 && addrtext_scope_use_ifname(sa)) {
426 parsedname = if_indextoname(scope, scopeptr);
428 af_debug("if_indextoname rejected scope (errno=%s)",
431 /* fair enough, show it as a number then */
432 } else if (addrtext_our_errno(errno)) {
433 /* we use these for other purposes, urgh. */
434 perror("adns: adns_addr2text: if_indextoname"
435 " failed with unexpected error");
443 int r = snprintf(scopeptr, remain,
445 assert(r < *buflen_io - scopeoffset);
447 af_debug("printed scoped addr `%s'", buffer);
451 if (port_r) *port_r= ntohs(port);
455 char *adns__sockaddr_ntoa(const struct sockaddr *sa, char *buf) {
457 int len= ADNS_ADDR2TEXT_BUFLEN;
459 err= adns_addr2text(sa, 0, buf, &len, 0);
461 err= adns_addr2text(sa, adns_qf_addrlit_scope_numeric, buf, &len, 0);
467 * Reverse-domain parsing and construction.
470 int adns__make_reverse_domain(const struct sockaddr *sa, const char *zone,
471 char **buf_io, size_t bufsz,
477 const unsigned char *ap;
480 AF_IN_IN6_OTHER(sa->sa_family, {
482 if (!zone) zone= "in-addr.arpa";
485 if (!zone) zone= "ip6.arpa";
490 req += strlen(zone) + 1;
494 p= malloc(req); if (!p) return errno;
499 SOCKADDR_IN_IN6(const, sa, sin, {
500 aa= ntohl(sin->sin_addr.s_addr);
501 for (i=0; i<4; i++) {
502 p += sprintf(p, "%d", (int)(aa & 0xff));
507 ap= sin6->sin6_addr.s6_addr + 16;
508 for (i=0; i<16; i++) {
510 for (j=0; j<2; j++) {
512 *p++= (y < 10) ? y + '0' : y - 10 + 'a';
524 static int inet_rev_parsecomp(const char *p, size_t n) {
526 if (n > 3) return -1;
529 if ('0' <= *p && *p <= '9') i= 10*i + *p++ - '0';
535 static void inet_rev_mkaddr(adns_sockaddr *addr, const byte *ipv) {
536 struct in_addr *v4 = &addr->inet.sin_addr;
537 v4->s_addr= htonl((ipv[3]<<24) | (ipv[2]<<16) |
538 (ipv[1]<<8) | (ipv[0]));
541 static int inet6_rev_parsecomp(const char *p, size_t n) {
542 if (n != 1) return -1;
543 else if ('0' <= *p && *p <= '9') return *p - '0';
544 else if ('a' <= *p && *p <= 'f') return *p - 'a' + 10;
545 else if ('A' <= *p && *p <= 'F') return *p - 'a' + 10;
549 static void inet6_rev_mkaddr(adns_sockaddr *addr, const byte *ipv) {
550 struct in6_addr *v6 = &addr->inet6.sin6_addr;
551 unsigned char *a= v6->s6_addr;
555 a[i]= (ipv[31-2*i] << 4) | (ipv[30-2*i] << 0);
558 static const struct revparse_domain {
559 int af; /* address family */
560 int nrevlab; /* n of reverse-address labels */
561 adns_rrtype rrtype; /* forward-lookup type */
563 int (*rev_parsecomp)(const char *p, size_t n);
564 /* parse a single component from a label; return the integer value, or -1
565 * if it was unintelligible.
568 void (*rev_mkaddr)(adns_sockaddr *addr, const byte *ipv);
569 /* write out the parsed protocol address from a vector of parsed components */
571 const char *const tail[3]; /* tail label names */
572 } revparse_domains[NREVDOMAINS] = {
573 { AF_INET, 4, adns_r_a, inet_rev_parsecomp, inet_rev_mkaddr,
574 { DNS_INADDR_ARPA, 0 } },
575 { AF_INET6, 32, adns_r_aaaa, inet6_rev_parsecomp, inet6_rev_mkaddr,
576 { DNS_IP6_ARPA, 0 } },
579 #define REVDOMAIN_MAP(rps, labnum) \
580 ((labnum) ? (rps)->map : (1 << NREVDOMAINS) - 1)
582 int adns__revparse_label(struct revparse_state *rps, int labnum,
583 const char *dgram, int labstart, int lablen) {
584 const char *label = dgram+labstart;
585 unsigned f= REVDOMAIN_MAP(rps, labnum);
586 const struct revparse_domain *rpd;
591 for (rpd=revparse_domains, i=0, d=1; i<NREVDOMAINS; rpd++, i++, d <<= 1) {
592 if (!(f & d)) continue;
593 if (labnum >= rpd->nrevlab) {
594 tp = rpd->tail[labnum - rpd->nrevlab];
595 if (!tp || strncmp(label, tp, lablen) != 0 || tp[lablen])
598 ac= rpd->rev_parsecomp(label, lablen);
599 if (ac < 0) goto mismatch;
600 assert(labnum < sizeof(rps->ipv[i]));
601 rps->ipv[i][labnum]= ac;
614 int adns__revparse_done(struct revparse_state *rps,
615 const char *dgram, int nlabels,
616 adns_rrtype *rrtype_r, adns_sockaddr *addr_r) {
617 unsigned f= REVDOMAIN_MAP(rps, nlabels);
618 const struct revparse_domain *rpd;
622 for (rpd=revparse_domains, i=0, d=1; i<NREVDOMAINS; rpd++, i++, d <<= 1) {
623 if (!(f & d)) continue;
624 if (nlabels >= rpd->nrevlab && !rpd->tail[nlabels - rpd->nrevlab])
625 { found = i; continue; }
629 assert(found >= 0); assert(f == (1 << found));
631 rpd= &revparse_domains[found];
632 *rrtype_r= rpd->rrtype;
633 addr_r->sa.sa_family= rpd->af;
634 rpd->rev_mkaddr(addr_r, rps->ipv[found]);