3 * - address-family specific code
6 * This file is part of adns, which is
7 * Copyright (C) 1997-2000,2003,2006,2014 Ian Jackson
8 * Copyright (C) 2014 Mark Wooding
9 * Copyright (C) 1999-2000,2003,2006 Tony Finch
10 * Copyright (C) 1991 Massachusetts Institute of Technology
11 * (See the file INSTALL for full details.)
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 3, or (at your option)
18 * This program is distributed in the hope that it will be useful,
19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 * GNU General Public License for more details.
23 * You should have received a copy of the GNU General Public License
24 * along with this program; if not, write to the Free Software Foundation.
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 static int textaddr_check_qf(adns_queryflags flags
) {
260 if (flags
& ~(adns_queryflags
)(adns_qf_addrlit_scope_forbid
|
261 adns_qf_addrlit_scope_numeric
|
262 adns_qf_addrlit_ipv4_quadonly
|
268 int adns_text2addr(const char *text
, uint16_t port
, adns_queryflags flags
,
269 struct sockaddr
*sa
, socklen_t
*salen_io
) {
271 char copybuf
[INET6_ADDRSTRLEN
];
272 const char *parse
=text
;
273 const char *scopestr
=0;
278 r
= textaddr_check_qf(flags
); if (r
) return r
;
280 #define INVAL(how) do{ \
281 af_debug("invalid: %s: `%s'", how, text); \
285 #define AFCORE(INETx,SINx,sinx) \
287 dst = &SINx(,sa)->sinx##_addr; \
288 portp = &SINx(,sa)->sinx##_port; \
289 needlen= sizeof(*SINx(,sa));
291 if (!strchr(text
, ':')) { /* INET */
293 AFCORE(INET
,SIN
,sin
);
297 AFCORE(INET6
,SIN6
,sin6
);
299 const char *percent
= strchr(text
, '%');
301 ptrdiff_t lhslen
= percent
- text
;
302 if (lhslen
>= INET6_ADDRSTRLEN
) INVAL("scoped addr lhs too long");
303 memcpy(copybuf
, text
, lhslen
);
309 af_debug("will parse scoped addr `%s' %% `%s'", parse
, scopestr
);
316 if (scopestr
&& (flags
& adns_qf_addrlit_scope_forbid
))
317 INVAL("scoped addr but _scope_forbid");
319 if (*salen_io
< needlen
) {
324 memset(sa
, 0, needlen
);
327 *portp
= htons(port
);
329 if (af
== AF_INET
&& !(flags
& adns_qf_addrlit_ipv4_quadonly
)) {
330 /* we have to use inet_aton to deal with non-dotted-quad literals */
331 int r
= inet_aton(parse
,&SIN(,sa
)->sin_addr
);
332 if (!r
) INVAL("inet_aton rejected");
334 int r
= inet_pton(af
,parse
,dst
);
335 if (!r
) INVAL("inet_pton rejected");
342 unsigned long scope
= strtoul(scopestr
,&ep
,10);
343 if (errno
==ERANGE
) INVAL("numeric scope id too large for unsigned long");
346 if (scope
> ~(uint32_t)0)
347 INVAL("numeric scope id too large for uint32_t");
349 if (flags
& adns_qf_addrlit_scope_numeric
)
350 INVAL("non-numeric scope but _scope_numeric");
351 if (!addrtext_scope_use_ifname(sa
)) {
352 af_debug("cannot convert non-numeric scope"
353 " in non-link-local addr `%s'", text
);
357 scope
= if_nametoindex(scopestr
);
359 /* RFC3493 says "No errors are defined". It's not clear
360 * whether that is supposed to mean if_nametoindex "can't
361 * fail" (other than by the supplied name not being that of an
362 * interface) which seems unrealistic, or that it conflates
363 * all its errors together by failing to set errno, or simply
364 * that they didn't bother to document the errors.
366 * glibc, FreeBSD and OpenBSD all set errno (to ENXIO when
367 * appropriate). See Debian bug #749349.
369 * We attempt to deal with this by clearing errno to start
370 * with, and then perhaps mapping the results. */
371 af_debug("if_nametoindex rejected scope name (errno=%s)",
375 } else if (addrtext_our_errno(errno
)) {
376 /* we use these for other purposes, urgh. */
377 perror("adns: adns_text2addr: if_nametoindex"
378 " failed with unexpected error");
384 if (scope
> ~(uint32_t)0) {
385 fprintf(stderr
,"adns: adns_text2addr: if_nametoindex"
386 " returned an interface index >=2^32 which will not fit"
387 " in sockaddr_in6.sin6_scope_id");
393 SIN6(,sa
)->sin6_scope_id
= scope
;
394 } /* if (scopestr) */
400 int adns_addr2text(const struct sockaddr
*sa
, adns_queryflags flags
,
401 char *buffer
, int *buflen_io
, int *port_r
) {
405 r
= textaddr_check_qf(flags
); if (r
) return r
;
407 if (*buflen_io
< ADNS_ADDR2TEXT_BUFLEN
) {
408 *buflen_io
= ADNS_ADDR2TEXT_BUFLEN
;
412 SOCKADDR_IN_IN6_OTHER(const, sa
, sin
, {
413 src
= &sin
->sin_addr
; port
= sin
->sin_port
;
415 src
= &sin6
->sin6_addr
; port
= sin6
->sin6_port
;
420 const char *ok
= inet_ntop(sa
->sa_family
, src
, buffer
, *buflen_io
);
423 if (sa
->sa_family
== AF_INET6
) {
424 uint32_t scope
= SIN6(const,sa
)->sin6_scope_id
;
426 if (flags
& adns_qf_addrlit_scope_forbid
)
428 int scopeoffset
= strlen(buffer
);
429 int remain
= *buflen_io
- scopeoffset
;
430 char *scopeptr
= buffer
+ scopeoffset
;
431 assert(remain
>= IF_NAMESIZE
+1/*%*/);
432 *scopeptr
++= '%'; remain
--;
434 af_debug("will print scoped addr `%.*s' %% %"PRIu32
"",
435 scopeoffset
,buffer
, scope
);
436 if (scope
<= UINT_MAX
/* so we can pass it to if_indextoname */
437 && !(flags
& adns_qf_addrlit_scope_numeric
)
438 && addrtext_scope_use_ifname(sa
)) {
439 parsedname
= if_indextoname(scope
, scopeptr
);
441 af_debug("if_indextoname rejected scope (errno=%s)",
444 /* fair enough, show it as a number then */
445 } else if (addrtext_our_errno(errno
)) {
446 /* we use these for other purposes, urgh. */
447 perror("adns: adns_addr2text: if_indextoname"
448 " failed with unexpected error");
456 int r
= snprintf(scopeptr
, remain
,
458 assert(r
< *buflen_io
- scopeoffset
);
460 af_debug("printed scoped addr `%s'", buffer
);
464 if (port_r
) *port_r
= ntohs(port
);
468 char *adns__sockaddr_ntoa(const struct sockaddr
*sa
, char *buf
) {
470 int len
= ADNS_ADDR2TEXT_BUFLEN
;
472 err
= adns_addr2text(sa
, 0, buf
, &len
, 0);
474 err
= adns_addr2text(sa
, adns_qf_addrlit_scope_numeric
, buf
, &len
, 0);
480 * Reverse-domain parsing and construction.
483 int adns__make_reverse_domain(const struct sockaddr
*sa
, const char *zone
,
484 char **buf_io
, size_t bufsz
,
490 const unsigned char *ap
;
493 AF_IN_IN6_OTHER(sa
->sa_family
, {
495 if (!zone
) zone
= "in-addr.arpa";
498 if (!zone
) zone
= "ip6.arpa";
503 req
+= strlen(zone
) + 1;
507 p
= malloc(req
); if (!p
) return errno
;
512 SOCKADDR_IN_IN6(const, sa
, sin
, {
513 aa
= ntohl(sin
->sin_addr
.s_addr
);
514 for (i
=0; i
<4; i
++) {
515 p
+= sprintf(p
, "%d", (int)(aa
& 0xff));
520 ap
= sin6
->sin6_addr
.s6_addr
+ 16;
521 for (i
=0; i
<16; i
++) {
523 for (j
=0; j
<2; j
++) {
525 *p
++= (y
< 10) ? y
+ '0' : y
- 10 + 'a';
537 #define REVPARSE_P_L(labnum) \
538 const char *p= dgram + rps->labstart[labnum]; \
539 int l= rps->lablen[labnum]
541 * REVPARSE_P_L(int labnum);
544 * const struct revparse_state *rps;
546 * const char *p; // start of label labnum in dgram
547 * int l; // length of label in dgram
550 static bool revparse_check_tail(struct revparse_state
*rps
,
551 const char *dgram
, int nlabels
,
552 int bodylen
, const char *inarpa
) {
555 if (nlabels
!= bodylen
+2) return 0;
556 for (i
=0; i
<2; i
++) {
557 REVPARSE_P_L(bodylen
+i
);
558 const char *want
= !i ? inarpa
: "arpa";
559 if (!adns__labels_equal(p
,l
, want
,strlen(want
))) return 0;
564 static bool revparse_atoi(const char *p
, int l
, int base
,
565 unsigned max
, unsigned *v_r
) {
567 if (l
>1 && p
[0]=='0') return 0;
571 int c
= ctype_toupper(*p
++);
572 if ('0'<=c
&& c
<='9') tv
= c
-'0';
573 else if ('A'<=c
&& c
<='Z') tv
= c
-'A'+10;
575 if (tv
>= base
) return 0;
584 static bool revparse_inet(struct revparse_state
*rps
,
585 const char *dgram
, int nlabels
,
586 adns_rrtype
*rrtype_r
, adns_sockaddr
*addr_r
) {
587 if (!revparse_check_tail(rps
,dgram
,nlabels
,4,"in-addr")) return 0;
591 for (i
=3; i
>=0; i
--) {
594 if (!revparse_atoi(p
,l
,10,255,&v
)) return 0;
599 addr_r
->inet
.sin_family
= AF_INET
;
600 addr_r
->inet
.sin_addr
.s_addr
= htonl(a
);
604 static bool revparse_inet6(struct revparse_state
*rps
,
605 const char *dgram
, int nlabels
,
606 adns_rrtype
*rrtype_r
, adns_sockaddr
*addr_r
) {
607 if (!revparse_check_tail(rps
,dgram
,nlabels
,32,"ip6")) return 0;
610 memset(addr_r
,0,sizeof(*addr_r
));
611 unsigned char *a
= addr_r
->inet6
.sin6_addr
.s6_addr
+16;
612 for (i
=0; i
<32; ) { /* i incremented in inner loop */
614 for (j
=0; j
<2; j
++, i
++) {
617 if (!revparse_atoi(p
,l
,16,15,&v
)) return 0;
623 *rrtype_r
= adns_r_aaaa
;
624 addr_r
->inet
.sin_family
= AF_INET6
;
628 bool adns__revparse_label(struct revparse_state
*rps
, int labnum
,
629 const char *dgram
, int labstart
, int lablen
) {
630 if (labnum
>= MAXREVLABELS
)
633 assert(labstart
<= 65535);
634 assert(lablen
<= 255);
635 rps
->labstart
[labnum
] = labstart
;
636 rps
->lablen
[labnum
] = lablen
;
640 bool adns__revparse_done(struct revparse_state
*rps
,
641 const char *dgram
, int nlabels
,
642 adns_rrtype
*rrtype_r
, adns_sockaddr
*addr_r
) {
644 revparse_inet(rps
,dgram
,nlabels
,rrtype_r
,addr_r
) ||
645 revparse_inet6(rps
,dgram
,nlabels
,rrtype_r
,addr_r
);