Commit | Line | Data |
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5628df75 | 1 | /* |
18d49d56 | 2 | * adns.h |
47a6797e | 3 | * - adns user-visible API |
18d49d56 | 4 | */ |
5 | /* | |
d942707d | 6 | * |
7 | * This file is | |
ae8cc977 | 8 | * Copyright (C) 1997-2000,2003,2006 Ian Jackson |
d942707d | 9 | * |
10 | * It is part of adns, which is | |
ae8cc977 | 11 | * Copyright (C) 1997-2000,2003,2006 Ian Jackson |
12 | * Copyright (C) 1999-2000,2003,2006 Tony Finch | |
13 | * Copyright (C) 1991 Massachusetts Institute of Technology | |
14 | * | |
e576be50 | 15 | * This program is free software; you can redistribute it and/or modify |
16 | * it under the terms of the GNU General Public License as published by | |
17 | * the Free Software Foundation; either version 2, or (at your option) | |
18 | * any later version. | |
19 | * | |
20 | * This program is distributed in the hope that it will be useful, | |
21 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
22 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
23 | * GNU General Public License for more details. | |
d942707d | 24 | * |
25 | * | |
bef232ae | 26 | * For the benefit of certain LGPL'd `omnibus' software which |
27 | * provides a uniform interface to various things including adns, I | |
28 | * make the following additional licence. I do this because the GPL | |
29 | * would otherwise force either the omnibus software to be GPL'd or | |
30 | * the adns-using part to be distributed separately. | |
d942707d | 31 | * |
bef232ae | 32 | * So: you may also redistribute and/or modify adns.h (but only the |
d942707d | 33 | * public header file adns.h and not any other part of adns) under the |
34 | * terms of the GNU Library General Public License as published by the | |
35 | * Free Software Foundation; either version 2 of the License, or (at | |
36 | * your option) any later version. | |
e576be50 | 37 | * |
d942707d | 38 | * Note that adns itself is GPL'd. Authors of adns-using applications |
39 | * with GPL-incompatible licences, and people who distribute adns with | |
40 | * applications where the whole distribution is not GPL'd, are still | |
41 | * likely to be in violation of the GPL. Anyone who wants to do this | |
42 | * should contact Ian Jackson. Please note that to avoid encouraging | |
bef232ae | 43 | * people to infringe the GPL as it applies to the body of adns, Ian |
44 | * thinks that if you take advantage of the special exception to | |
45 | * redistribute just adns.h under the LGPL, you should retain this | |
46 | * paragraph in its place in the appropriate copyright statements. | |
d942707d | 47 | * |
48 | * | |
49 | * You should have received a copy of the GNU General Public License, | |
50 | * or the GNU Library General Public License, as appropriate, along | |
51 | * with this program; if not, write to the Free Software Foundation, | |
a719a4be | 52 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
53 | * | |
d942707d | 54 | * |
a719a4be | 55 | * $Id$ |
e576be50 | 56 | */ |
a17d3a1d | 57 | |
58 | #ifndef ADNS_H_INCLUDED | |
59 | #define ADNS_H_INCLUDED | |
60 | ||
4353a5c4 | 61 | #include <stdio.h> |
d3a102c4 | 62 | #include <stdarg.h> |
4353a5c4 | 63 | |
5aabad0d | 64 | #include <sys/types.h> |
964344fc | 65 | #include <sys/socket.h> |
66 | #include <netinet/in.h> | |
636b69b1 | 67 | #include <sys/time.h> |
68 | #include <unistd.h> | |
5806b745 | 69 | #include <net/if.h> |
964344fc | 70 | |
8fedcfeb | 71 | #ifdef __cplusplus |
72 | extern "C" { /* I really dislike this - iwj. */ | |
73 | #endif | |
74 | ||
09957b1c | 75 | /* All struct in_addr anywhere in adns are in NETWORK byte order. */ |
76 | ||
964344fc | 77 | typedef struct adns__state *adns_state; |
78 | typedef struct adns__query *adns_query; | |
a17d3a1d | 79 | |
deb1edb6 | 80 | typedef enum { /* In general, or together the desired flags: */ |
81 | adns_if_none= 0x0000,/* no flags. nicer than 0 for some compilers */ | |
b5bc5076 | 82 | adns_if_noenv= 0x0001,/* do not look at environment */ |
83 | adns_if_noerrprint= 0x0002,/* never print to stderr (_debug overrides) */ | |
84 | adns_if_noserverwarn=0x0004,/* do not warn to stderr about duff servers etc */ | |
85 | adns_if_debug= 0x0008,/* enable all output to stderr plus debug msgs */ | |
86 | adns_if_logpid= 0x0080,/* include pid in diagnostic output */ | |
87 | adns_if_noautosys= 0x0010,/* do not make syscalls at every opportunity */ | |
88 | adns_if_eintr= 0x0020,/* allow _wait and _synchronous to return EINTR */ | |
89 | adns_if_nosigpipe= 0x0040,/* applic has SIGPIPE ignored, do not protect */ | |
90 | adns_if_checkc_entex=0x0100,/* consistency checks on entry/exit to adns fns */ | |
91 | adns_if_checkc_freq= 0x0300 /* consistency checks very frequently (slow!) */ | |
a17d3a1d | 92 | } adns_initflags; |
93 | ||
deb1edb6 | 94 | typedef enum { /* In general, or together the desired flags: */ |
95 | adns_qf_none= 0x00000000,/* no flags */ | |
b5bc5076 | 96 | adns_qf_search= 0x00000001,/* use the searchlist */ |
97 | adns_qf_usevc= 0x00000002,/* use a virtual circuit (TCP conn) */ | |
98 | adns_qf_owner= 0x00000004,/* fill in the owner field in the answer */ | |
99 | adns_qf_quoteok_query= 0x00000010,/* allow special chars in query domain */ | |
100 | adns_qf_quoteok_cname= 0x00000000,/* ... in CNAME we go via (now default) */ | |
101 | adns_qf_quoteok_anshost=0x00000040,/* ... in things supposedly hostnames */ | |
102 | adns_qf_quotefail_cname=0x00000080,/* refuse if quote-req chars in CNAME we go via */ | |
103 | adns_qf_cname_loose= 0x00000100,/* allow refs to CNAMEs - without, get _s_cname */ | |
104 | adns_qf_cname_forbid= 0x00000200,/* don't follow CNAMEs, instead give _s_cname */ | |
cdf51ff0 | 105 | adns_qf_ipv6_mapv4= 0x00001000,/* ... return IPv4 addresses as v6-mapped */ |
5806b745 IJ |
106 | adns_qf_addrlit_scope_forbid=0x00002000,/* forbid %<scope> in IPv6 literals */ |
107 | adns_qf_addrlit_scope_numeric=0x00004000,/* %<scope> may only be numeric */ | |
108 | adns_qf_addrlit_ipv4_quadonly=0x00008000,/* reject non-dotted-quad ipv4 */ | |
b5bc5076 | 109 | adns__qf_internalmask= 0x0ff00000 |
a17d3a1d | 110 | } adns_queryflags; |
111 | ||
112 | typedef enum { | |
2c6eb096 | 113 | adns_rrt_typemask= 0x0ffff, |
d24b603f | 114 | adns_rrt_reprmask= 0xffffff, |
b0a32b17 | 115 | adns__qtf_deref_bit=0x10000,/* internal version of ..._deref below */ |
2ed355aa | 116 | adns__qtf_mail822= 0x20000,/* return mailboxes in RFC822 rcpt field fmt */ |
2bd4b9f4 | 117 | |
b0a32b17 MW |
118 | adns__qtf_bigaddr=0x1000000,/* use the new larger sockaddr union */ |
119 | ||
120 | adns__qtf_deref= adns__qtf_deref_bit|adns__qtf_bigaddr | |
121 | ,/* dereference domains; perhaps get extra data */ | |
122 | ||
2bd4b9f4 | 123 | adns_r_unknown= 0x40000, |
124 | /* To use this, ask for records of type <rr-type-code>|adns_r_unknown. | |
2c6eb096 | 125 | * adns will not process the RDATA - you'll get adns_rr_byteblocks, |
126 | * where the int is the length and the unsigned char* points to the | |
127 | * data. String representation of the RR data (by adns_rrinfo) is as in | |
128 | * RFC3597. adns_rr_info will not return the type name in *rrtname_r | |
129 | * (due to memory management problems); *fmtname_r will be set to | |
130 | * "unknown". | |
2bd4b9f4 | 131 | * |
132 | * Do not specify adns_r_unknown along with a known RR type which | |
2c6eb096 | 133 | * requires domain name uncompression (see RFC3597 s4); domain names |
134 | * will not be uncompressed and the resulting data would be useless. | |
135 | * Asking for meta-RR types via adns_r_unknown will not work properly | |
136 | * either and may make adns complain about server misbehaviour, so don't | |
137 | * do that. | |
138 | * | |
139 | * Don't forget adns_qf_quoteok if that's what you want. */ | |
140 | ||
b5bc5076 | 141 | adns_r_none= 0, |
142 | ||
143 | adns_r_a= 1, | |
144 | ||
145 | adns_r_ns_raw= 2, | |
146 | adns_r_ns= adns_r_ns_raw|adns__qtf_deref, | |
147 | ||
148 | adns_r_cname= 5, | |
149 | ||
150 | adns_r_soa_raw= 6, | |
151 | adns_r_soa= adns_r_soa_raw|adns__qtf_mail822, | |
152 | ||
30d78b94 | 153 | adns_r_ptr_raw= 12, /* do not mind PTR with wrong or missing A */ |
b5bc5076 | 154 | adns_r_ptr= adns_r_ptr_raw|adns__qtf_deref, |
155 | ||
156 | adns_r_hinfo= 13, | |
157 | ||
158 | adns_r_mx_raw= 15, | |
159 | adns_r_mx= adns_r_mx_raw|adns__qtf_deref, | |
160 | ||
161 | adns_r_txt= 16, | |
162 | ||
163 | adns_r_rp_raw= 17, | |
164 | adns_r_rp= adns_r_rp_raw|adns__qtf_mail822, | |
2ed355aa | 165 | |
50e2b0c3 MW |
166 | adns_r_aaaa= 28, |
167 | ||
2ed355aa | 168 | /* For SRV records, query domain without _qf_quoteok_query must look |
169 | * as expected from SRV RFC with hostname-like Name. _With_ | |
170 | * _quoteok_query, any query domain is allowed. */ | |
171 | adns_r_srv_raw= 33, | |
172 | adns_r_srv= adns_r_srv_raw|adns__qtf_deref, | |
b5bc5076 | 173 | |
174 | adns_r_addr= adns_r_a|adns__qtf_deref | |
175 | ||
a17d3a1d | 176 | } adns_rrtype; |
177 | ||
b365d68a | 178 | /* |
179 | * In queries without qf_quoteok_*, all domains must have standard | |
180 | * legal syntax, or you get adns_s_querydomainvalid (if the query | |
181 | * domain contains bad characters) or adns_s_answerdomaininvalid (if | |
182 | * the answer contains bad characters). | |
183 | * | |
184 | * In queries _with_ qf_quoteok_*, domains in the query or response | |
185 | * may contain any characters, quoted according to RFC1035 5.1. On | |
186 | * input to adns, the char* is a pointer to the interior of a " | |
8af5175d | 187 | * delimited string, except that " may appear in it unquoted. On |
188 | * output, the char* is a pointer to a string which would be legal | |
189 | * either inside or outside " delimiters; any character which isn't | |
190 | * legal in a hostname (ie alphanumeric or hyphen) or one of _ / + | |
191 | * (the three other punctuation characters commonly abused in domain | |
192 | * names) will be quoted, as \X if it is a printing ASCII character or | |
193 | * \DDD otherwise. | |
194 | * | |
b365d68a | 195 | * If the query goes via a CNAME then the canonical name (ie, the |
196 | * thing that the CNAME record refers to) is usually allowed to | |
197 | * contain any characters, which will be quoted as above. With | |
198 | * adns_qf_quotefail_cname you get adns_s_answerdomaininvalid when | |
199 | * this happens. (This is a change from version 0.4 and earlier, in | |
200 | * which failing the query was the default, and you had to say | |
201 | * adns_qf_quoteok_cname to avoid this; that flag is now deprecated.) | |
202 | * | |
203 | * In version 0.4 and earlier, asking for _raw records containing | |
204 | * mailboxes without specifying _qf_quoteok_anshost was silly. This | |
205 | * is no longer the case. In this version only parts of responses | |
206 | * that are actually supposed to be hostnames will be refused by | |
207 | * default if quote-requiring characters are found. | |
208 | */ | |
209 | ||
210 | /* | |
211 | * If you ask for an RR which contains domains which are actually | |
212 | * encoded mailboxes, and don't ask for the _raw version, then adns | |
213 | * returns the mailbox formatted suitably for an RFC822 recipient | |
214 | * header field. The particular format used is that if the mailbox | |
215 | * requires quoting according to the rules in RFC822 then the | |
216 | * local-part is quoted in double quotes, which end at the next | |
7672a872 | 217 | * unescaped double quote (\ is the escape char, and is doubled, and |
218 | * is used to escape only \ and "). If the local-part is legal | |
219 | * without quoting according to RFC822, it is presented as-is. In any | |
220 | * case the local-part is followed by an @ and the domain. The domain | |
221 | * will not contain any characters not legal in hostnames. | |
222 | * | |
223 | * Unquoted local-parts may contain any printing 7-bit ASCII | |
224 | * except the punctuation characters ( ) < > @ , ; : \ " [ ] | |
225 | * I.e. they may contain alphanumerics, and the following | |
226 | * punctuation characters: ! # % ^ & * - _ = + { } . | |
227 | * | |
228 | * adns will reject local parts containing control characters (byte | |
229 | * values 0-31, 127-159, and 255) - these appear to be legal according | |
d0ac9ea0 | 230 | * to RFC822 (at least 0-127) but are clearly a bad idea. RFC1035 |
231 | * syntax does not make any distinction between a single RFC822 | |
232 | * quoted-string containing full stops, and a series of quoted-strings | |
233 | * separated by full stops; adns will return anything that isn't all | |
234 | * valid atoms as a single quoted-string. RFC822 does not allow | |
235 | * high-bit-set characters at all, but adns does allow them in | |
236 | * local-parts, treating them as needing quoting. | |
b365d68a | 237 | * |
238 | * If you ask for the domain with _raw then _no_ checking is done | |
239 | * (even on the host part, regardless of adns_qf_quoteok_anshost), and | |
240 | * you just get the domain name in master file format. | |
241 | * | |
242 | * If no mailbox is supplied the returned string will be `.' in either | |
d0ac9ea0 | 243 | * case. |
964344fc | 244 | */ |
245 | ||
a17d3a1d | 246 | typedef enum { |
b5bc5076 | 247 | adns_s_ok, |
248 | ||
249 | /* locally induced errors */ | |
250 | adns_s_nomemory, | |
251 | adns_s_unknownrrtype, | |
252 | adns_s_systemfail, | |
253 | ||
254 | adns_s_max_localfail= 29, | |
255 | ||
256 | /* remotely induced errors, detected locally */ | |
257 | adns_s_timeout, | |
258 | adns_s_allservfail, | |
259 | adns_s_norecurse, | |
260 | adns_s_invalidresponse, | |
261 | adns_s_unknownformat, | |
262 | ||
263 | adns_s_max_remotefail= 59, | |
264 | ||
265 | /* remotely induced errors, reported by remote server to us */ | |
266 | adns_s_rcodeservfail, | |
267 | adns_s_rcodeformaterror, | |
268 | adns_s_rcodenotimplemented, | |
269 | adns_s_rcoderefused, | |
270 | adns_s_rcodeunknown, | |
271 | ||
272 | adns_s_max_tempfail= 99, | |
273 | ||
274 | /* remote configuration errors */ | |
275 | adns_s_inconsistent, /* PTR gives domain whose A does not exist and match */ | |
276 | adns_s_prohibitedcname, /* CNAME, but eg A expected (not if _qf_loosecname) */ | |
277 | adns_s_answerdomaininvalid, | |
278 | adns_s_answerdomaintoolong, | |
279 | adns_s_invaliddata, | |
280 | ||
281 | adns_s_max_misconfig= 199, | |
282 | ||
283 | /* permanent problems with the query */ | |
284 | adns_s_querydomainwrong, | |
285 | adns_s_querydomaininvalid, | |
286 | adns_s_querydomaintoolong, | |
287 | ||
288 | adns_s_max_misquery= 299, | |
289 | ||
290 | /* permanent errors */ | |
291 | adns_s_nxdomain, | |
292 | adns_s_nodata, | |
293 | ||
294 | adns_s_max_permfail= 499 | |
295 | ||
a17d3a1d | 296 | } adns_status; |
297 | ||
b0a32b17 MW |
298 | typedef union { |
299 | struct sockaddr sa; | |
300 | struct sockaddr_in inet; | |
301 | } adns_sockaddr_v4only; | |
302 | ||
303 | typedef union { | |
304 | struct sockaddr sa; | |
305 | struct sockaddr_in inet; | |
306 | struct sockaddr_in6 inet6; | |
307 | } adns_sockaddr; | |
308 | ||
e8c505a5 | 309 | typedef struct { |
828d89bd | 310 | int len; |
b0a32b17 | 311 | adns_sockaddr addr; |
551ff40f | 312 | } adns_rr_addr; |
828d89bd | 313 | |
314 | typedef struct { | |
b0a32b17 MW |
315 | /* the old v4-only structure; handy if you have complicated binary |
316 | * compatibility problems. */ | |
317 | int len; | |
318 | adns_sockaddr_v4only addr; | |
319 | } adns_rr_addr_v4only; | |
320 | ||
321 | typedef struct { | |
1dfe95d8 | 322 | char *host; |
84fe28db | 323 | adns_status astatus; |
324 | int naddrs; /* temp fail => -1, perm fail => 0, s_ok => >0 */ | |
551ff40f | 325 | adns_rr_addr *addrs; |
c7836bc9 | 326 | } adns_rr_hostaddr; |
4353a5c4 | 327 | |
328 | typedef struct { | |
9ec44266 | 329 | char *(array[2]); |
4353a5c4 | 330 | } adns_rr_strpair; |
331 | ||
332 | typedef struct { | |
333 | int i; | |
1dfe95d8 | 334 | adns_rr_hostaddr ha; |
c7836bc9 | 335 | } adns_rr_inthostaddr; |
4353a5c4 | 336 | |
337 | typedef struct { | |
b5bc5076 | 338 | /* Used both for mx_raw, in which case i is the preference and str |
339 | * the domain, and for txt, in which case each entry has i for the | |
340 | * `text' length, and str for the data (which will have had an extra | |
341 | * nul appended so that if it was plain text it is now a | |
342 | * null-terminated string). | |
e062dcae | 343 | */ |
4353a5c4 | 344 | int i; |
345 | char *str; | |
346 | } adns_rr_intstr; | |
347 | ||
348 | typedef struct { | |
9ec44266 | 349 | adns_rr_intstr array[2]; |
350 | } adns_rr_intstrpair; | |
351 | ||
352 | typedef struct { | |
353 | char *mname, *rname; | |
4353a5c4 | 354 | unsigned long serial, refresh, retry, expire, minimum; |
355 | } adns_rr_soa; | |
84fe28db | 356 | |
357 | typedef struct { | |
2ed355aa | 358 | int priority, weight, port; |
359 | char *host; | |
360 | } adns_rr_srvraw; | |
361 | ||
362 | typedef struct { | |
363 | int priority, weight, port; | |
364 | adns_rr_hostaddr ha; | |
401c256a | 365 | } adns_rr_srvha; |
2ed355aa | 366 | |
367 | typedef struct { | |
2c6eb096 | 368 | int len; |
369 | unsigned char *data; | |
370 | } adns_rr_byteblock; | |
371 | ||
372 | typedef struct { | |
a17d3a1d | 373 | adns_status status; |
374 | char *cname; /* always NULL if query was for CNAME records */ | |
b5bc5076 | 375 | char *owner; /* only set if req'd in query flags; maybe 0 on error anyway */ |
86e7b8d9 | 376 | adns_rrtype type; /* guaranteed to be same as in query */ |
b5bc5076 | 377 | time_t expires;/*abs time. def only if _s_ok, nxdomain or nodata. NOT TTL!*/ |
b365d68a | 378 | int nrrs, rrsz; /* nrrs is 0 if an error occurs */ |
a17d3a1d | 379 | union { |
8e5b0abb | 380 | void *untyped; |
381 | unsigned char *bytes; | |
b5bc5076 | 382 | char *(*str); /* ns_raw, cname, ptr, ptr_raw */ |
383 | adns_rr_intstr *(*manyistr); /* txt (list strs ends with i=-1, str=0)*/ | |
384 | adns_rr_addr *addr; /* addr */ | |
385 | struct in_addr *inaddr; /* a */ | |
50e2b0c3 | 386 | struct in6_addr *in6addr; /* aaaa */ |
b5bc5076 | 387 | adns_rr_hostaddr *hostaddr; /* ns */ |
388 | adns_rr_intstrpair *intstrpair; /* hinfo */ | |
389 | adns_rr_strpair *strpair; /* rp, rp_raw */ | |
390 | adns_rr_inthostaddr *inthostaddr;/* mx */ | |
2c6eb096 | 391 | adns_rr_intstr *intstr; /* mx_raw */ |
b5bc5076 | 392 | adns_rr_soa *soa; /* soa, soa_raw */ |
2ed355aa | 393 | adns_rr_srvraw *srvraw; /* srv_raw */ |
401c256a | 394 | adns_rr_srvha *srvha;/* srv */ |
2c6eb096 | 395 | adns_rr_byteblock *byteblock; /* ...|unknown */ |
a17d3a1d | 396 | } rrs; |
e8c505a5 | 397 | } adns_answer; |
a17d3a1d | 398 | |
399 | /* Memory management: | |
400 | * adns_state and adns_query are actually pointers to malloc'd state; | |
401 | * On submission questions are copied, including the owner domain; | |
4353a5c4 | 402 | * Answers are malloc'd as a single piece of memory; pointers in the |
403 | * answer struct point into further memory in the answer. | |
a17d3a1d | 404 | * query_io: |
405 | * Must always be non-null pointer; | |
406 | * If *query_io is 0 to start with then any query may be returned; | |
407 | * If *query_io is !0 adns_query then only that query may be returned. | |
d3eea642 | 408 | * If the call is successful, *query_io, *answer_r, and *context_r |
409 | * will all be set. | |
a17d3a1d | 410 | * Errors: |
620c146d | 411 | * Return values are 0 or an errno value. |
412 | * | |
413 | * For _init, _init_strcfg, _submit and _synchronous, system errors | |
414 | * (eg, failure to create sockets, malloc failure, etc.) return errno | |
469fc855 | 415 | * values. EINVAL from _init et al means the configuration file |
416 | * is erroneous and cannot be parsed. | |
620c146d | 417 | * |
418 | * For _wait and _check failures are reported in the answer | |
226c5eef | 419 | * structure, and only 0, ESRCH or (for _check) EAGAIN is |
620c146d | 420 | * returned: if no (appropriate) requests are done adns_check returns |
226c5eef | 421 | * EAGAIN; if no (appropriate) requests are outstanding both |
620c146d | 422 | * adns_query and adns_wait return ESRCH. |
423 | * | |
424 | * Additionally, _wait can return EINTR if you set adns_if_eintr. | |
425 | * | |
426 | * All other errors (nameserver failure, timed out connections, &c) | |
427 | * are returned in the status field of the answer. After a | |
428 | * successful _wait or _check, if status is nonzero then nrrs will be | |
429 | * 0, otherwise it will be >0. type will always be the type | |
430 | * requested. | |
a17d3a1d | 431 | */ |
432 | ||
47a6797e | 433 | /* Threads: |
434 | * adns does not use any static modifiable state, so it | |
435 | * is safe to call adns_init several times and then use the | |
436 | * resulting adns_states concurrently. | |
437 | * However, it is NOT safe to make simultaneous calls into | |
438 | * adns using the same adns_state; a single adns_state must be used | |
439 | * only by one thread at a time. You can solve this problem by | |
440 | * having one adns_state per thread, or if that isn't feasible, you | |
441 | * could maintain a pool of adns_states. Unfortunately neither of | |
442 | * these approaches has optimal performance. | |
443 | */ | |
444 | ||
e563872a | 445 | int adns_init(adns_state *newstate_r, adns_initflags flags, |
36369543 | 446 | FILE *diagfile /*0=>stderr*/); |
447 | ||
e563872a | 448 | int adns_init_strcfg(adns_state *newstate_r, adns_initflags flags, |
36369543 | 449 | FILE *diagfile /*0=>discard*/, const char *configtext); |
c8c7c813 | 450 | |
d3a102c4 | 451 | typedef void adns_logcallbackfn(adns_state ads, void *logfndata, |
452 | const char *fmt, va_list al); | |
4db1559f | 453 | /* Will be called perhaps several times for each message; when the |
09ad6588 | 454 | * message is complete, the string implied by fmt and al will end in |
4db1559f | 455 | * a newline. Log messages start with `adns debug:' or `adns |
456 | * warning:' or `adns:' (for errors), or `adns debug [PID]:' | |
457 | * etc. if adns_if_logpid is set. */ | |
d3a102c4 | 458 | |
459 | int adns_init_logfn(adns_state *newstate_r, adns_initflags flags, | |
460 | const char *configtext /*0=>use default config files*/, | |
461 | adns_logcallbackfn *logfn /*0=>logfndata is a FILE* */, | |
462 | void *logfndata /*0 with logfn==0 => discard*/); | |
463 | ||
c8c7c813 | 464 | /* Configuration: |
465 | * adns_init reads /etc/resolv.conf, which is expected to be (broadly | |
fb7fbb66 | 466 | * speaking) in the format expected by libresolv, and then |
467 | * /etc/resolv-adns.conf if it exists. adns_init_strcfg is instead | |
468 | * passed a string which is interpreted as if it were the contents of | |
469 | * resolv.conf or resolv-adns.conf. In general, configuration which | |
470 | * is set later overrides any that is set earlier. | |
c8c7c813 | 471 | * |
fb7fbb66 | 472 | * Standard directives understood in resolv[-adns].conf: |
c8c7c813 | 473 | * |
474 | * nameserver <address> | |
475 | * Must be followed by the IP address of a nameserver. Several | |
476 | * nameservers may be specified, and they will be tried in the order | |
477 | * found. There is a compiled in limit, currently 5, on the number | |
478 | * of nameservers. (libresolv supports only 3 nameservers.) | |
479 | * | |
480 | * search <domain> ... | |
481 | * Specifies the search list for queries which specify | |
482 | * adns_qf_search. This is a list of domains to append to the query | |
483 | * domain. The query domain will be tried as-is either before all | |
484 | * of these or after them, depending on the ndots option setting | |
485 | * (see below). | |
486 | * | |
487 | * domain <domain> | |
488 | * This is present only for backward compatibility with obsolete | |
489 | * versions of libresolv. It should not be used, and is interpreted | |
490 | * by adns as if it were `search' - note that this is subtly | |
491 | * different to libresolv's interpretation of this directive. | |
492 | * | |
493 | * sortlist <addr>/<mask> ... | |
494 | * Should be followed by a sequence of IP-address and netmask pairs, | |
495 | * separated by spaces. They may be specified as | |
496 | * eg. 172.30.206.0/24 or 172.30.206.0/255.255.255.0. Currently up | |
497 | * to 15 pairs may be specified (but note that libresolv only | |
498 | * supports up to 10). | |
499 | * | |
500 | * options | |
501 | * Should followed by one or more options, separated by spaces. | |
502 | * Each option consists of an option name, followed by optionally | |
503 | * a colon and a value. Options are listed below. | |
504 | * | |
fb7fbb66 | 505 | * Non-standard directives understood in resolv[-adns].conf: |
c8c7c813 | 506 | * |
507 | * clearnameservers | |
508 | * Clears the list of nameservers, so that further nameserver lines | |
509 | * start again from the beginning. | |
510 | * | |
511 | * include <filename> | |
512 | * The specified file will be read. | |
513 | * | |
fb7fbb66 | 514 | * Additionally, adns will ignore lines in resolv[-adns].conf which |
515 | * start with a #. | |
c8c7c813 | 516 | * |
517 | * Standard options understood: | |
518 | * | |
519 | * debug | |
520 | * Enables debugging output from the resolver, which will be written | |
521 | * to stderr. | |
522 | * | |
523 | * ndots:<count> | |
524 | * Affects whether queries with adns_qf_search will be tried first | |
525 | * without adding domains from the searchlist, or whether the bare | |
526 | * query domain will be tried last. Queries which contain at least | |
527 | * <count> dots will be tried bare first. The default is 1. | |
528 | * | |
529 | * Non-standard options understood: | |
530 | * | |
531 | * adns_checkc:none | |
532 | * adns_checkc:entex | |
533 | * adns_checkc:freq | |
534 | * Changes the consistency checking frequency; this overrides the | |
535 | * setting of adns_if_check_entex, adns_if_check_freq, or neither, | |
536 | * in the flags passed to adns_init. | |
537 | * | |
538 | * There are a number of environment variables which can modify the | |
539 | * behaviour of adns. They take effect only if adns_init is used, and | |
540 | * the caller of adns_init can disable them using adns_if_noenv. In | |
541 | * each case there is both a FOO and an ADNS_FOO; the latter is | |
542 | * interpreted later so that it can override the former. Unless | |
543 | * otherwise stated, environment variables are interpreted after | |
fb7fbb66 | 544 | * resolv[-adns].conf are read, in the order they are listed here. |
c8c7c813 | 545 | * |
546 | * RES_CONF, ADNS_RES_CONF | |
547 | * A filename, whose contets are in the format of resolv.conf. | |
548 | * | |
549 | * RES_CONF_TEXT, ADNS_RES_CONF_TEXT | |
550 | * A string in the format of resolv.conf. | |
551 | * | |
552 | * RES_OPTIONS, ADNS_RES_OPTIONS | |
553 | * These are parsed as if they appeared in the `options' line of a | |
554 | * resolv.conf. In addition to being parsed at this point in the | |
555 | * sequence, they are also parsed at the very beginning before | |
556 | * resolv.conf or any other environment variables are read, so that | |
557 | * any debug option can affect the processing of the configuration. | |
558 | * | |
559 | * LOCALDOMAIN, ADNS_LOCALDOMAIN | |
560 | * These are interpreted as if their contents appeared in a `search' | |
561 | * line in resolv.conf. | |
562 | */ | |
a17d3a1d | 563 | |
564 | int adns_synchronous(adns_state ads, | |
565 | const char *owner, | |
566 | adns_rrtype type, | |
e563872a | 567 | adns_queryflags flags, |
9d95094c | 568 | adns_answer **answer_r); |
e8c505a5 | 569 | |
570 | /* NB: if you set adns_if_noautosys then _submit and _check do not | |
620c146d | 571 | * make any system calls; you must use some of the asynch-io event |
572 | * processing functions to actually get things to happen. | |
e8c505a5 | 573 | */ |
a17d3a1d | 574 | |
575 | int adns_submit(adns_state ads, | |
576 | const char *owner, | |
577 | adns_rrtype type, | |
e563872a | 578 | adns_queryflags flags, |
a17d3a1d | 579 | void *context, |
964344fc | 580 | adns_query *query_r); |
a17d3a1d | 581 | |
3ccea6ee | 582 | /* The owner should be quoted in master file format. */ |
583 | ||
964344fc | 584 | int adns_check(adns_state ads, |
a17d3a1d | 585 | adns_query *query_io, |
9d95094c | 586 | adns_answer **answer_r, |
587 | void **context_r); | |
a17d3a1d | 588 | |
589 | int adns_wait(adns_state ads, | |
590 | adns_query *query_io, | |
9d95094c | 591 | adns_answer **answer_r, |
592 | void **context_r); | |
a17d3a1d | 593 | |
940356bd | 594 | /* same as adns_wait but uses poll(2) internally */ |
595 | int adns_wait_poll(adns_state ads, | |
596 | adns_query *query_io, | |
597 | adns_answer **answer_r, | |
598 | void **context_r); | |
599 | ||
3955725c | 600 | void adns_cancel(adns_query query); |
a17d3a1d | 601 | |
620c146d | 602 | /* The adns_query you get back from _submit is valid (ie, can be |
603 | * legitimately passed into adns functions) until it is returned by | |
604 | * adns_check or adns_wait, or passed to adns_cancel. After that it | |
605 | * must not be used. You can rely on it not being reused until the | |
606 | * first adns_submit or _transact call using the same adns_state after | |
607 | * it became invalid, so you may compare it for equality with other | |
608 | * query handles until you next call _query or _transact. | |
636b69b1 | 609 | * |
610 | * _submit and _synchronous return ENOSYS if they don't understand the | |
611 | * query type. | |
e576be50 | 612 | */ |
a17d3a1d | 613 | |
b365d68a | 614 | int adns_submit_reverse(adns_state ads, |
615 | const struct sockaddr *addr, | |
616 | adns_rrtype type, | |
e563872a | 617 | adns_queryflags flags, |
b365d68a | 618 | void *context, |
619 | adns_query *query_r); | |
d7449548 | 620 | /* type must be _r_ptr or _r_ptr_raw. _qf_search is ignored. |
621 | * addr->sa_family must be AF_INET or you get ENOSYS. | |
622 | */ | |
b365d68a | 623 | |
2b1c6979 | 624 | int adns_submit_reverse_any(adns_state ads, |
625 | const struct sockaddr *addr, | |
626 | const char *rzone, | |
627 | adns_rrtype type, | |
628 | adns_queryflags flags, | |
629 | void *context, | |
630 | adns_query *query_r); | |
631 | /* For RBL-style reverse `zone's; look up | |
632 | * <reversed-address>.<zone> | |
633 | * Any type is allowed. _qf_search is ignored. | |
634 | * addr->sa_family must be AF_INET or you get ENOSYS. | |
635 | */ | |
636 | ||
620c146d | 637 | void adns_finish(adns_state ads); |
e576be50 | 638 | /* You may call this even if you have queries outstanding; |
639 | * they will be cancelled. | |
640 | */ | |
a17d3a1d | 641 | |
5806b745 IJ |
642 | #define ADNS_ADDR2TEXT_BUFLEN \ |
643 | (INET6_ADDRSTRLEN + 1/*%*/ \ | |
644 | + ((IF_NAMESIZE-1) > 9 ? (IF_NAMESIZE-1) : 9/*uint32*/) \ | |
645 | + 1/* nul; included in IF_NAMESIZE */) | |
646 | ||
647 | int adns_text2addr(const char *text, uint16_t port, adns_queryflags flags, | |
648 | struct sockaddr *sa_r, | |
649 | socklen_t *salen_io /* updated iff OK or ENOSPC */); | |
650 | int adns_addr2text(const struct sockaddr *sa, adns_queryflags flags, | |
651 | char *buffer, int *buflen_io /* updated ONLY on ENOSPC */, | |
652 | int *port_r /* may be 0 */); | |
653 | /* | |
654 | * port is always in host byte order and is simply copied to and | |
655 | * from the appropriate sockaddr field (byteswapped as necessary). | |
656 | * | |
657 | * The only flags supported are adns_qf_addrlit_...; others are | |
658 | * ignored. | |
659 | * | |
660 | * Error return values are: | |
661 | * | |
662 | * ENOSPC Output buffer is too small. Can only happen if | |
663 | * *buflen_io < ADNS_ADDR2TEXT_BUFLEN or | |
664 | * *salen_io < sizeof(adns_sockaddr). On return, | |
665 | * *buflen_io or *salen_io has been updated by adns. | |
666 | * | |
667 | * EINVAL text has invalid syntax. | |
668 | * | |
669 | * text represents an address family not supported by | |
670 | * this version of adns. | |
671 | * | |
672 | * Scoped address supplied (text contained "%" or | |
673 | * sin6_scope_id nonzero) but caller specified | |
674 | * adns_qf_addrlit_scope_forbid. | |
675 | * | |
676 | * Scope name (rather than number) supplied in text but | |
677 | * caller specified adns_qf_addrlit_scope_numeric. | |
678 | * | |
679 | * EAFNOSUPPORT sa->sa_family is not supported (addr2text only). | |
680 | * | |
681 | * Only if neither adns_qf_addrlit_scope_forbid nor | |
682 | * adns_qf_addrlit_scope_numeric are set: | |
683 | * | |
684 | * ENOSYS Scope name supplied in text but IPv6 address part of | |
685 | * sockaddr is not a link local address. | |
686 | * | |
687 | * ENXIO Scope name supplied in text but if_nametoindex | |
688 | * said it wasn't a valid local interface name. | |
689 | * | |
690 | * EIO Scoped address supplied but if_nametoindex failed | |
691 | * in an unexpected way; adns has printed a message to | |
692 | * stderr. | |
693 | * | |
694 | * any other if_nametoindex failed in a more-or-less expected way. | |
695 | */ | |
964344fc | 696 | |
958ad1f0 | 697 | void adns_forallqueries_begin(adns_state ads); |
8ce38e76 | 698 | adns_query adns_forallqueries_next(adns_state ads, void **context_r); |
620c146d | 699 | /* Iterator functions, which you can use to loop over the outstanding |
958ad1f0 | 700 | * (submitted but not yet successfuly checked/waited) queries. |
a8768e80 | 701 | * |
958ad1f0 | 702 | * You can only have one iteration going at once. You may call _begin |
703 | * at any time; after that, an iteration will be in progress. You may | |
704 | * only call _next when an iteration is in progress - anything else | |
705 | * may coredump. The iteration remains in progress until _next | |
706 | * returns 0, indicating that all the queries have been walked over, | |
707 | * or ANY other adns function is called with the same adns_state (or a | |
708 | * query in the same adns_state). There is no need to explicitly | |
709 | * finish an iteration. | |
710 | * | |
8ce38e76 | 711 | * context_r may be 0. *context_r may not be set when _next returns 0. |
964344fc | 712 | */ |
a17d3a1d | 713 | |
28de6442 | 714 | void adns_checkconsistency(adns_state ads, adns_query qu); |
3e2e5fab | 715 | /* Checks the consistency of adns's internal data structures. |
716 | * If any error is found, the program will abort(). | |
28de6442 | 717 | * You may pass 0 for qu; if you pass non-null then additional checks |
718 | * are done to make sure that qu is a valid query. | |
3e2e5fab | 719 | */ |
720 | ||
620c146d | 721 | /* |
722 | * Example expected/legal calling sequence for submit/check/wait: | |
a17d3a1d | 723 | * adns_init |
724 | * adns_submit 1 | |
725 | * adns_submit 2 | |
726 | * adns_submit 3 | |
727 | * adns_wait 1 | |
226c5eef | 728 | * adns_check 3 -> EAGAIN |
a17d3a1d | 729 | * adns_wait 2 |
730 | * adns_wait 3 | |
731 | * .... | |
732 | * adns_finish | |
620c146d | 733 | */ |
734 | ||
735 | /* | |
736 | * Entrypoints for generic asynch io: | |
737 | * (these entrypoints are not very useful except in combination with * | |
738 | * some of the other I/O model calls which can tell you which fds to | |
739 | * be interested in): | |
740 | * | |
741 | * Note that any adns call may cause adns to open and close fds, so | |
742 | * you must call beforeselect or beforepoll again just before | |
743 | * blocking, or you may not have an up-to-date list of it's fds. | |
744 | */ | |
745 | ||
746 | int adns_processany(adns_state ads); | |
747 | /* Gives adns flow-of-control for a bit. This will never block, and | |
748 | * can be used with any threading/asynch-io model. If some error | |
749 | * occurred which might cause an event loop to spin then the errno | |
750 | * value is returned. | |
751 | */ | |
752 | ||
753 | int adns_processreadable(adns_state ads, int fd, const struct timeval *now); | |
754 | int adns_processwriteable(adns_state ads, int fd, const struct timeval *now); | |
755 | int adns_processexceptional(adns_state ads, int fd, const struct timeval *now); | |
756 | /* Gives adns flow-of-control so that it can process incoming data | |
757 | * from, or send outgoing data via, fd. Very like _processany. If it | |
758 | * returns zero then fd will no longer be readable or writeable | |
759 | * (unless of course more data has arrived since). adns will _only_ | |
0a106d94 | 760 | * use that fd and only in the manner specified, regardless of whether |
620c146d | 761 | * adns_if_noautosys was specified. |
762 | * | |
763 | * adns_processexceptional should be called when select(2) reports an | |
764 | * exceptional condition, or poll(2) reports POLLPRI. | |
765 | * | |
766 | * It is fine to call _processreabable or _processwriteable when the | |
767 | * fd is not ready, or with an fd that doesn't belong to adns; it will | |
768 | * then just return 0. | |
769 | * | |
770 | * If some error occurred which might prevent an event loop to spin | |
771 | * then the errno value is returned. | |
772 | */ | |
773 | ||
774 | void adns_processtimeouts(adns_state ads, const struct timeval *now); | |
775 | /* Gives adns flow-of-control so that it can process any timeouts | |
776 | * which might have happened. Very like _processreadable/writeable. | |
777 | * | |
778 | * now may be 0; if it isn't, *now must be the current time, recently | |
779 | * obtained from gettimeofday. | |
780 | */ | |
781 | ||
782 | void adns_firsttimeout(adns_state ads, | |
783 | struct timeval **tv_mod, struct timeval *tv_buf, | |
784 | struct timeval now); | |
785 | /* Asks adns when it would first like the opportunity to time | |
786 | * something out. now must be the current time, from gettimeofday. | |
787 | * | |
788 | * If tv_mod points to 0 then tv_buf must be non-null, and | |
789 | * _firsttimeout will fill in *tv_buf with the time until the first | |
790 | * timeout, and make *tv_mod point to tv_buf. If adns doesn't have | |
791 | * anything that might need timing out it will leave *tv_mod as 0. | |
792 | * | |
793 | * If *tv_mod is not 0 then tv_buf is not used. adns will update | |
794 | * *tv_mod if it has any earlier timeout, and leave it alone if it | |
795 | * doesn't. | |
796 | * | |
797 | * This call will not actually do any I/O, or change the fds that adns | |
798 | * is using. It always succeeds and never blocks. | |
799 | */ | |
800 | ||
801 | void adns_globalsystemfailure(adns_state ads); | |
802 | /* If serious problem(s) happen which globally affect your ability to | |
803 | * interact properly with adns, or adns's ability to function | |
804 | * properly, you or adns can call this function. | |
805 | * | |
806 | * All currently outstanding queries will be made to fail with | |
807 | * adns_s_systemfail, and adns will close any stream sockets it has | |
808 | * open. | |
809 | * | |
810 | * This is used by adns, for example, if gettimeofday() fails. | |
811 | * Without this the program's event loop might start to spin ! | |
812 | * | |
813 | * This call will never block. | |
814 | */ | |
815 | ||
816 | /* | |
817 | * Entrypoints for select-loop based asynch io: | |
818 | */ | |
819 | ||
820 | void adns_beforeselect(adns_state ads, int *maxfd, fd_set *readfds, | |
821 | fd_set *writefds, fd_set *exceptfds, | |
822 | struct timeval **tv_mod, struct timeval *tv_buf, | |
823 | const struct timeval *now); | |
824 | /* Find out file descriptors adns is interested in, and when it would | |
825 | * like the opportunity to time something out. If you do not plan to | |
826 | * block then tv_mod may be 0. Otherwise, tv_mod and tv_buf are as | |
827 | * for adns_firsttimeout. readfds, writefds, exceptfds and maxfd_io may | |
828 | * not be 0. | |
829 | * | |
d3a102c4 | 830 | * If tv_mod is 0 on entry then this will never actually do any I/O, |
831 | * or change the fds that adns is using or the timeouts it wants. In | |
832 | * any case it won't block, and it will set the timeout to zero if a | |
833 | * query finishes in _beforeselect. | |
620c146d | 834 | */ |
835 | ||
836 | void adns_afterselect(adns_state ads, int maxfd, const fd_set *readfds, | |
837 | const fd_set *writefds, const fd_set *exceptfds, | |
838 | const struct timeval *now); | |
839 | /* Gives adns flow-of-control for a bit; intended for use after | |
840 | * select. This is just a fancy way of calling adns_processreadable/ | |
841 | * writeable/timeouts as appropriate, as if select had returned the | |
842 | * data being passed. Always succeeds. | |
843 | */ | |
844 | ||
845 | /* | |
846 | * Example calling sequence: | |
a17d3a1d | 847 | * |
e8c505a5 | 848 | * adns_init _noautosys |
a17d3a1d | 849 | * loop { |
620c146d | 850 | * adns_beforeselect |
a17d3a1d | 851 | * select |
620c146d | 852 | * adns_afterselect |
e8c505a5 | 853 | * ... |
854 | * adns_submit / adns_check | |
855 | * ... | |
a17d3a1d | 856 | * } |
857 | */ | |
858 | ||
620c146d | 859 | /* |
860 | * Entrypoints for poll-loop based asynch io: | |
861 | */ | |
862 | ||
863 | struct pollfd; | |
864 | /* In case your system doesn't have it or you forgot to include | |
865 | * <sys/poll.h>, to stop the following declarations from causing | |
866 | * problems. If your system doesn't have poll then the following | |
867 | * entrypoints will not be defined in libadns. Sorry ! | |
868 | */ | |
869 | ||
b5bc5076 | 870 | int adns_beforepoll(adns_state ads, struct pollfd *fds, |
871 | int *nfds_io, int *timeout_io, | |
620c146d | 872 | const struct timeval *now); |
873 | /* Finds out which fd's adns is interested in, and when it would like | |
874 | * to be able to time things out. This is in a form suitable for use | |
875 | * with poll(2). | |
876 | * | |
877 | * On entry, usually fds should point to at least *nfds_io structs. | |
878 | * adns will fill up to that many structs will information for poll, | |
879 | * and record in *nfds_io how many structs it filled. If it wants to | |
880 | * listen for more structs then *nfds_io will be set to the number | |
881 | * required and _beforepoll will return ERANGE. | |
882 | * | |
620c146d | 883 | * You may call _beforepoll with fds==0 and *nfds_io 0, in which case |
884 | * adns will fill in the number of fds that it might be interested in | |
fc6a52ae | 885 | * in *nfds_io, and always return either 0 (if it is not interested in |
886 | * any fds) or ERANGE (if it is). | |
887 | * | |
c912639e | 888 | * NOTE that (unless now is 0) adns may acquire additional fds |
fc6a52ae | 889 | * from one call to the next, so you must put adns_beforepoll in a |
890 | * loop, rather than assuming that the second call (with the buffer | |
891 | * size requested by the first) will not return ERANGE. | |
620c146d | 892 | * |
893 | * adns only ever sets POLLIN, POLLOUT and POLLPRI in its pollfd | |
894 | * structs, and only ever looks at those bits. POLLPRI is required to | |
fc6a52ae | 895 | * detect TCP Urgent Data (which should not be used by a DNS server) |
620c146d | 896 | * so that adns can know that the TCP stream is now useless. |
897 | * | |
898 | * In any case, *timeout_io should be a timeout value as for poll(2), | |
899 | * which adns will modify downwards as required. If the caller does | |
fc6a52ae | 900 | * not plan to block then *timeout_io should be 0 on entry, or |
901 | * alternatively, timeout_io may be 0. (Alternatively, the caller may | |
902 | * use _beforeselect with timeout_io==0 to find out about file | |
903 | * descriptors, and use _firsttimeout is used to find out when adns | |
904 | * might want to time something out.) | |
620c146d | 905 | * |
906 | * adns_beforepoll will return 0 on success, and will not fail for any | |
907 | * reason other than the fds buffer being too small (ERANGE). | |
908 | * | |
c912639e | 909 | * This call will never actually do any I/O. If you supply the |
910 | * current time it will not change the fds that adns is using or the | |
911 | * timeouts it wants. | |
912 | * | |
913 | * In any case this call won't block. | |
620c146d | 914 | */ |
915 | ||
3eb20edd | 916 | #define ADNS_POLLFDS_RECOMMENDED 3 |
620c146d | 917 | /* If you allocate an fds buf with at least RECOMMENDED entries then |
918 | * you are unlikely to need to enlarge it. You are recommended to do | |
919 | * so if it's convenient. However, you must be prepared for adns to | |
920 | * require more space than this. | |
921 | */ | |
922 | ||
923 | void adns_afterpoll(adns_state ads, const struct pollfd *fds, int nfds, | |
924 | const struct timeval *now); | |
925 | /* Gives adns flow-of-control for a bit; intended for use after | |
926 | * poll(2). fds and nfds should be the results from poll(). pollfd | |
927 | * structs mentioning fds not belonging to adns will be ignored. | |
928 | */ | |
929 | ||
930 | ||
86e7b8d9 | 931 | adns_status adns_rr_info(adns_rrtype type, |
932 | const char **rrtname_r, const char **fmtname_r, | |
933 | int *len_r, | |
934 | const void *datap, char **data_r); | |
b365d68a | 935 | /* |
b365d68a | 936 | * Get information about a query type, or convert reply data to a |
937 | * textual form. type must be specified, and the official name of the | |
938 | * corresponding RR type will be returned in *rrtname_r, and | |
939 | * information about the processing style in *fmtname_r. The length | |
940 | * of the table entry in an answer for that type will be returned in | |
941 | * in *len_r. Any or all of rrtname_r, fmtname_r and len_r may be 0. | |
942 | * If fmtname_r is non-null then *fmtname_r may be null on return, | |
943 | * indicating that no special processing is involved. | |
944 | * | |
945 | * data_r be must be non-null iff datap is. In this case *data_r will | |
946 | * be set to point to a string pointing to a representation of the RR | |
947 | * data in master file format. (The owner name, timeout, class and | |
948 | * type will not be present - only the data part of the RR.) The | |
949 | * memory will have been obtained from malloc() and must be freed by | |
950 | * the caller. | |
86e7b8d9 | 951 | * |
952 | * Usually this routine will succeed. Possible errors include: | |
953 | * adns_s_nomemory | |
ea1e31e3 | 954 | * adns_s_rrtypeunknown |
86e7b8d9 | 955 | * adns_s_invaliddata (*datap contained garbage) |
956 | * If an error occurs then no memory has been allocated, | |
957 | * and *rrtname_r, *fmtname_r, *len_r and *data_r are undefined. | |
b365d68a | 958 | * |
959 | * There are some adns-invented data formats which are not official | |
960 | * master file formats. These include: | |
961 | * | |
962 | * Mailboxes if __qtf_mail822: these are just included as-is. | |
963 | * | |
964 | * Addresses (adns_rr_addr): these may be of pretty much any type. | |
965 | * The representation is in two parts: first, a word for the address | |
966 | * family (ie, in AF_XXX, the XXX), and then one or more items for the | |
967 | * address itself, depending on the format. For an IPv4 address the | |
968 | * syntax is INET followed by the dotted quad (from inet_ntoa). | |
969 | * Currently only IPv4 is supported. | |
970 | * | |
a6f1dc92 | 971 | * Text strings (as in adns_rr_txt) appear inside double quotes, and |
972 | * use \" and \\ to represent " and \, and \xHH to represent | |
973 | * characters not in the range 32-126. | |
974 | * | |
b365d68a | 975 | * Hostname with addresses (adns_rr_hostaddr): this consists of the |
a6f1dc92 | 976 | * hostname, as usual, followed by the adns_status value, as an |
977 | * abbreviation, and then a descriptive string (encoded as if it were | |
978 | * a piece of text), for the address lookup, followed by zero or more | |
06f8e611 | 979 | * addresses enclosed in ( and ). If the result was a temporary |
b365d68a | 980 | * failure, then a single ? appears instead of the ( ). If the |
06f8e611 | 981 | * result was a permanent failure then an empty pair of parentheses |
b365d68a | 982 | * appears (which a space in between). For example, one of the NS |
a6f1dc92 | 983 | * records for greenend.org.uk comes out like |
984 | * ns.chiark.greenend.org.uk ok "OK" ( INET 195.224.76.132 ) | |
b365d68a | 985 | * an MX referring to a nonexistent host might come out like: |
a6f1dc92 | 986 | * 50 sun2.nsfnet-relay.ac.uk nxdomain "No such domain" ( ) |
b365d68a | 987 | * and if nameserver information is not available you might get: |
a6f1dc92 | 988 | * dns2.spong.dyn.ml.org timeout "DNS query timed out" ? |
86e7b8d9 | 989 | */ |
990 | ||
31144a72 | 991 | const char *adns_strerror(adns_status st); |
9da4a044 | 992 | const char *adns_errabbrev(adns_status st); |
ac77ffc1 | 993 | const char *adns_errtypeabbrev(adns_status st); |
620c146d | 994 | /* Like strerror but for adns_status values. adns_errabbrev returns |
995 | * the abbreviation of the error - eg, for adns_s_timeout it returns | |
ac77ffc1 | 996 | * "timeout". adns_errtypeabbrev returns the abbreviation of the |
997 | * error class: ie, for values up to adns_s_max_XXX it will return the | |
998 | * string XXX. You MUST NOT call these functions with status values | |
620c146d | 999 | * not returned by the same adns library. |
1000 | */ | |
31144a72 | 1001 | |
02b47faa | 1002 | #ifdef __cplusplus |
1003 | } /* end of extern "C" */ | |
1004 | #endif | |
a17d3a1d | 1005 | #endif |