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(sa) ((struct sockaddr_in *)(sa))
48 #define CSIN(sa) ((const struct sockaddr_in *)(sa))
50 #define SIN6(sa) ((struct sockaddr_in6 *)(sa))
51 #define CSIN6(sa) ((const struct sockaddr_in6 *)(sa))
53 static void unknown_af(int af
) NONRETURNING
;
54 static void unknown_af(int af
) {
55 fprintf(stderr
, "ADNS INTERNAL: unknown address family %d\n", af
);
60 * SOCKADDR_IN_IN6(CNST, struct sockaddr *sa, SIN, {
61 * // struct sockaddr_in *const SIN; // implicitly
64 * // struct sockaddr_in6 *const SIN6; // implicitly
68 * SOCKADDR_IN_IN6_PAIR(CNST, struct sockaddr *sa, SINA,
69 * struct sockaddr *sb, SINB, {
70 * // struct sockaddr_in *const SINA; // implicitly
71 * // struct sockaddr_in *const SINB; // implicitly
74 * // struct sockaddr_in6 *const SINA6; // implicitly
75 * // struct sockaddr_in6 *const SINB6; // implicitly
79 * SOCKADDR_IN_IN6_OTHER(CNST, struct sockaddr *sa, SIN, { in }, { in6 }, {
80 * code for other address family
83 * AF_IN_IN6_OTHER(af, { in }, { in6 }, { other })
85 * Executes the first or second block according to the AF in sa. CNST
86 * may be `const' or empty. For _PAIR, sa and sb must be same AF.
88 * All except _OTHER handle unknown AFs with unknown_af.
90 * Code blocks may not contain , outside parens.
92 #define AF_IN_IN6_OTHER(af, for_inet, for_inet6, other) \
93 if ((af) == AF_INET) { \
95 } else if ((af) == AF_INET6) { \
100 #define SOCKADDR_IN_IN6_OTHER(cnst, sa, sin, for_inet, for_inet6, other) \
101 AF_IN_IN6_OTHER((sa)->sa_family, { \
102 cnst struct sockaddr_in *const sin = (cnst void*)(sa); \
105 cnst struct sockaddr_in6 *const sin##6 = (cnst void*)(sa); \
110 #define SOCKADDR_IN_IN6(cnst, sa, sin, for_inet, for_inet6) \
111 SOCKADDR_IN_IN6_OTHER(cnst, sa, sin, for_inet, for_inet6, { \
112 unknown_af((sa)->sa_family); \
114 #define SOCKADDR_IN_IN6_PAIR(cnst, sa, sina, sb, sinb, for_inet, for_inet6) \
116 assert((sa)->sa_family == (sb)->sa_family); \
117 SOCKADDR_IN_IN6(cnst, sa, sina, { \
118 cnst struct sockaddr_in *const sinb = (cnst void*)(sb); \
121 cnst struct sockaddr_in6 *const sinb##6 = (cnst void*)(sb); \
126 int adns__addrs_equal_raw(const struct sockaddr
*a
,
127 int bf
, const void *b
) {
128 if (a
->sa_family
!= bf
) return 0;
130 SOCKADDR_IN_IN6(const, a
, sin
, {
131 return sin
->sin_addr
.s_addr
== ((const struct in_addr
*)b
)->s_addr
;
133 return !memcmp(&sin6
->sin6_addr
, b
, sizeof(struct in6_addr
));
137 int adns__addrs_equal(const adns_sockaddr
*a
, const adns_sockaddr
*b
) {
138 return adns__addrs_equal_raw(&a
->sa
, b
->sa
.sa_family
,
139 adns__sockaddr_addr(&b
->sa
));
142 int adns__sockaddrs_equal(const struct sockaddr
*sa
,
143 const struct sockaddr
*sb
) {
144 if (!adns__addrs_equal_raw(sa
, sb
->sa_family
, adns__sockaddr_addr(sb
)))
146 SOCKADDR_IN_IN6_PAIR(const, sa
, sina
, sb
, sinb
, {
147 return sina
->sin_port
== sinb
->sin_port
;
149 return sina6
->sin6_port
== sinb6
->sin6_port
&&
150 sina6
->sin6_scope_id
== sinb6
->sin6_scope_id
;
154 int adns__addr_width(int af
) {
155 AF_IN_IN6_OTHER(af
, {
164 void adns__prefix_mask(adns_sockaddr
*sa
, int len
) {
165 SOCKADDR_IN_IN6(, &sa
->sa
, sin
, {
167 sin
->sin_addr
.s_addr
= htonl(!len ?
0 : 0xffffffff << (32-len
));
171 unsigned char *m
= sin6
->sin6_addr
.s6_addr
;
174 if (j
) m
[i
++]= (0xff << (8-j
)) & 0xff;
175 memset(m
+i
, 0, 16-i
);
179 int adns__guess_prefix_length(const adns_sockaddr
*sa
) {
180 SOCKADDR_IN_IN6(const, &sa
->sa
, sin
, {
181 unsigned a
= (ntohl(sin
->sin_addr
.s_addr
) >> 24) & 0xff;
182 if (a
< 128) return 8;
183 else if (a
< 192) return 16;
184 else if (a
< 224) return 24;
192 int adns__addr_matches(int af
, const void *addr
,
193 const adns_sockaddr
*base
, const adns_sockaddr
*mask
)
195 if (af
!= base
->sa
.sa_family
) return 0;
196 SOCKADDR_IN_IN6_PAIR(const, &base
->sa
, sbase
, &mask
->sa
, smask
, {
197 const struct in_addr
*v4
= addr
;
198 return (v4
->s_addr
& smask
->sin_addr
.s_addr
)
199 == sbase
->sin_addr
.s_addr
;
203 const char *b
= sbase6
->sin6_addr
.s6_addr
;
204 const char *m
= smask6
->sin6_addr
.s6_addr
;
205 for (i
= 0; i
< 16; i
++)
206 if ((a
[i
] & m
[i
]) != b
[i
]) return 0;
211 const void *adns__sockaddr_addr(const struct sockaddr
*sa
) {
212 SOCKADDR_IN_IN6(const, sa
, sin
, {
213 return &sin
->sin_addr
;
215 return &sin6
->sin6_addr
;
219 void adns__addr_inject(const void *a
, adns_sockaddr
*sa
) {
220 SOCKADDR_IN_IN6( , &sa
->sa
, sin
, {
221 memcpy(&sin
->sin_addr
, a
, sizeof(sin
->sin_addr
));
223 memcpy(&sin6
->sin6_addr
, a
, sizeof(sin6
->sin6_addr
));
228 * addr2text and text2addr
231 #define ADDRFAM_DEBUG
233 static void af_debug_func(const char *fmt
, ...) {
237 vfprintf(stderr
,fmt
,al
);
241 # define af_debug(fmt,...) \
242 (af_debug_func("%s: " fmt "\n", __func__, __VA_ARGS__))
244 # define af_debug(fmt,...) ((void)("" fmt "", __VA_ARGS__))
247 static bool addrtext_our_errno(int e
) {
255 static bool addrtext_scope_use_ifname(const struct sockaddr
*sa
) {
256 const struct in6_addr
*in6
= &CSIN6(sa
)->sin6_addr
;
258 IN6_IS_ADDR_LINKLOCAL(in6
) ||
259 IN6_IS_ADDR_MC_LINKLOCAL(in6
);
262 int adns_text2addr(const char *text
, uint16_t port
, adns_queryflags flags
,
263 struct sockaddr
*sa
, socklen_t
*salen_io
) {
265 char copybuf
[INET6_ADDRSTRLEN
];
266 const char *parse
=text
;
267 const char *scopestr
=0;
272 #define INVAL(how) do{ \
273 af_debug("invalid: %s: `%s'", how, text); \
277 #define AFCORE(INETx,SINx,sinx) \
279 dst = &SINx(sa)->sinx##_addr; \
280 portp = &SINx(sa)->sinx##_port; \
281 needlen= sizeof(*SINx(sa));
283 if (!strchr(text
, ':')) { /* INET */
285 AFCORE(INET
,SIN
,sin
);
289 AFCORE(INET6
,SIN6
,sin6
);
291 const char *percent
= strchr(text
, '%');
293 ptrdiff_t lhslen
= percent
- text
;
294 if (lhslen
>= INET6_ADDRSTRLEN
) INVAL("scoped addr lhs too long");
295 memcpy(copybuf
, text
, lhslen
);
301 af_debug("will parse scoped addr `%s' %% `%s'", parse
, scopestr
);
308 if (scopestr
&& (flags
& adns_qf_addrlit_scope_forbid
))
309 INVAL("scoped addr but _scope_forbid");
311 if (*salen_io
< needlen
) {
316 memset(sa
, 0, needlen
);
319 *portp
= htons(port
);
321 if (af
== AF_INET
&& !(flags
& adns_qf_addrlit_ipv4_quadonly
)) {
322 /* we have to use inet_aton to deal with non-dotted-quad literals */
323 int r
= inet_aton(parse
,&SIN(sa
)->sin_addr
);
324 if (!r
) INVAL("inet_aton rejected");
326 int r
= inet_pton(af
,parse
,dst
);
327 if (!r
) INVAL("inet_pton rejected");
334 unsigned long scope
= strtoul(scopestr
,&ep
,10);
335 if (errno
==ERANGE
) INVAL("numeric scope id too large for unsigned long");
338 if (scope
> ~(uint32_t)0)
339 INVAL("numeric scope id too large for uint32_t");
341 if (flags
& adns_qf_addrlit_scope_numeric
)
342 INVAL("non-numeric scope but _scope_numeric");
343 if (!addrtext_scope_use_ifname(sa
)) {
344 af_debug("cannot convert non-numeric scope"
345 " in non-link-local addr `%s'", text
);
349 scope
= if_nametoindex(scopestr
);
351 /* RFC3493 says "No errors are defined". It's not clear
352 * whether that is supposed to mean if_nametoindex "can't
353 * fail" (other than by the supplied name not being that of an
354 * interface) which seems unrealistic, or that it conflates
355 * all its errors together by failing to set errno, or simply
356 * that they didn't bother to document the errors.
358 * glibc, FreeBSD and OpenBSD all set errno (to ENXIO when
359 * appropriate). See Debian bug #749349.
361 * We attempt to deal with this by clearing errno to start
362 * with, and then perhaps mapping the results. */
363 af_debug("if_nametoindex rejected scope name (errno=%s)",
367 } else if (addrtext_our_errno(errno
)) {
368 /* we use these for other purposes, urgh. */
369 perror("adns: adns_text2addr: if_nametoindex"
370 " failed with unexpected error");
376 if (scope
> ~(uint32_t)0) {
377 fprintf(stderr
,"adns: adns_text2addr: if_nametoindex"
378 " returned an interface index >=2^32 which will not fit"
379 " in sockaddr_in6.sin6_scope_id");
385 SIN6(sa
)->sin6_scope_id
= scope
;
386 } /* if (scopestr) */
392 int adns_addr2text(const struct sockaddr
*sa
, adns_queryflags flags
,
393 char *buffer
, int *buflen_io
, int *port_r
) {
397 if (*buflen_io
< ADNS_ADDR2TEXT_BUFLEN
) {
398 *buflen_io
= ADNS_ADDR2TEXT_BUFLEN
;
402 SOCKADDR_IN_IN6_OTHER(const, sa
, sin
, {
403 src
= &sin
->sin_addr
; port
= sin
->sin_port
;
405 src
= &sin6
->sin6_addr
; port
= sin6
->sin6_port
;
410 const char *ok
= inet_ntop(sa
->sa_family
, src
, buffer
, *buflen_io
);
413 if (sa
->sa_family
== AF_INET6
) {
414 uint32_t scope
= CSIN6(sa
)->sin6_scope_id
;
416 if (flags
& adns_qf_addrlit_scope_forbid
)
418 int scopeoffset
= strlen(buffer
);
419 int remain
= *buflen_io
- scopeoffset
;
420 char *scopeptr
= buffer
+ scopeoffset
;
421 assert(remain
>= IF_NAMESIZE
+1/*%*/);
422 *scopeptr
++= '%'; remain
--;
424 af_debug("will print scoped addr `%.*s' %% %"PRIu32
"",
425 scopeoffset
,buffer
, scope
);
426 if (scope
<= UINT_MAX
/* so we can pass it to if_indextoname */
427 && !(flags
& adns_qf_addrlit_scope_numeric
)
428 && addrtext_scope_use_ifname(sa
)) {
429 parsedname
= if_indextoname(scope
, scopeptr
);
431 af_debug("if_indextoname rejected scope (errno=%s)",
434 /* fair enough, show it as a number then */
435 } else if (addrtext_our_errno(errno
)) {
436 /* we use these for other purposes, urgh. */
437 perror("adns: adns_addr2text: if_indextoname"
438 " failed with unexpected error");
446 int r
= snprintf(scopeptr
, remain
,
448 assert(r
< *buflen_io
- scopeoffset
);
450 af_debug("printed scoped addr `%s'", buffer
);
454 if (port_r
) *port_r
= ntohs(port
);
458 char *adns__sockaddr_ntoa(const struct sockaddr
*sa
, char *buf
) {
460 int len
= ADNS_ADDR2TEXT_BUFLEN
;
462 err
= adns_addr2text(sa
, 0, buf
, &len
, 0);
464 err
= adns_addr2text(sa
, adns_qf_addrlit_scope_numeric
, buf
, &len
, 0);
470 * Reverse-domain parsing and construction.
473 int adns__make_reverse_domain(const struct sockaddr
*sa
, const char *zone
,
474 char **buf_io
, size_t bufsz
,
480 const unsigned char *ap
;
483 AF_IN_IN6_OTHER(sa
->sa_family
, {
485 if (!zone
) zone
= "in-addr.arpa";
488 if (!zone
) zone
= "ip6.arpa";
493 req
+= strlen(zone
) + 1;
497 p
= malloc(req
); if (!p
) return errno
;
502 SOCKADDR_IN_IN6(const, sa
, sin
, {
503 aa
= ntohl(sin
->sin_addr
.s_addr
);
504 for (i
=0; i
<4; i
++) {
505 p
+= sprintf(p
, "%d", (int)(aa
& 0xff));
510 ap
= sin6
->sin6_addr
.s6_addr
+ 16;
511 for (i
=0; i
<16; i
++) {
513 for (j
=0; j
<2; j
++) {
515 *p
++= (y
< 10) ? y
+ '0' : y
- 10 + 'a';
527 static int inet_rev_parsecomp(const char *p
, size_t n
) {
529 if (n
> 3) return -1;
532 if ('0' <= *p
&& *p
<= '9') i
= 10*i
+ *p
++ - '0';
538 static void inet_rev_mkaddr(adns_sockaddr
*addr
, const byte
*ipv
) {
539 struct in_addr
*v4
= &addr
->inet
.sin_addr
;
540 v4
->s_addr
= htonl((ipv
[3]<<24) | (ipv
[2]<<16) |
541 (ipv
[1]<<8) | (ipv
[0]));
544 static int inet6_rev_parsecomp(const char *p
, size_t n
) {
545 if (n
!= 1) return -1;
546 else if ('0' <= *p
&& *p
<= '9') return *p
- '0';
547 else if ('a' <= *p
&& *p
<= 'f') return *p
- 'a' + 10;
548 else if ('A' <= *p
&& *p
<= 'F') return *p
- 'a' + 10;
552 static void inet6_rev_mkaddr(adns_sockaddr
*addr
, const byte
*ipv
) {
553 struct in6_addr
*v6
= &addr
->inet6
.sin6_addr
;
554 unsigned char *a
= v6
->s6_addr
;
558 a
[i
]= (ipv
[31-2*i
] << 4) | (ipv
[30-2*i
] << 0);
561 static const struct revparse_domain
{
562 int af
; /* address family */
563 int nrevlab
; /* n of reverse-address labels */
564 adns_rrtype rrtype
; /* forward-lookup type */
566 int (*rev_parsecomp
)(const char *p
, size_t n
);
567 /* parse a single component from a label; return the integer value, or -1
568 * if it was unintelligible.
571 void (*rev_mkaddr
)(adns_sockaddr
*addr
, const byte
*ipv
);
572 /* write out the parsed protocol address from a vector of parsed components */
574 const char *const tail
[3]; /* tail label names */
575 } revparse_domains
[NREVDOMAINS
] = {
576 { AF_INET
, 4, adns_r_a
, inet_rev_parsecomp
, inet_rev_mkaddr
,
577 { DNS_INADDR_ARPA
, 0 } },
578 { AF_INET6
, 32, adns_r_aaaa
, inet6_rev_parsecomp
, inet6_rev_mkaddr
,
579 { DNS_IP6_ARPA
, 0 } },
582 #define REVDOMAIN_MAP(rps, labnum) \
583 ((labnum) ? (rps)->map : (1 << NREVDOMAINS) - 1)
585 int adns__revparse_label(struct revparse_state
*rps
, int labnum
,
586 const char *label
, int lablen
) {
587 unsigned f
= REVDOMAIN_MAP(rps
, labnum
);
588 const struct revparse_domain
*rpd
;
593 for (rpd
=revparse_domains
, i
=0, d
=1; i
<NREVDOMAINS
; rpd
++, i
++, d
<<= 1) {
594 if (!(f
& d
)) continue;
595 if (labnum
>= rpd
->nrevlab
) {
596 tp
= rpd
->tail
[labnum
- rpd
->nrevlab
];
597 if (!tp
|| strncmp(label
, tp
, lablen
) != 0 || tp
[lablen
])
600 ac
= rpd
->rev_parsecomp(label
, lablen
);
601 if (ac
< 0) goto mismatch
;
602 assert(labnum
< sizeof(rps
->ipv
[i
]));
603 rps
->ipv
[i
][labnum
]= ac
;
616 int adns__revparse_done(struct revparse_state
*rps
, int nlabels
,
617 adns_rrtype
*rrtype_r
, adns_sockaddr
*addr_r
) {
618 unsigned f
= REVDOMAIN_MAP(rps
, nlabels
);
619 const struct revparse_domain
*rpd
;
623 for (rpd
=revparse_domains
, i
=0, d
=1; i
<NREVDOMAINS
; rpd
++, i
++, d
<<= 1) {
624 if (!(f
& d
)) continue;
625 if (nlabels
>= rpd
->nrevlab
&& !rpd
->tail
[nlabels
- rpd
->nrevlab
])
626 { found
= i
; continue; }
630 assert(found
>= 0); assert(f
== (1 << found
));
632 rpd
= &revparse_domains
[found
];
633 *rrtype_r
= rpd
->rrtype
;
634 addr_r
->sa
.sa_family
= rpd
->af
;
635 rpd
->rev_mkaddr(addr_r
, rps
->ipv
[found
]);