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 bool 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 bool 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
]);