5628df75 |
1 | /* |
18d49d56 |
2 | * adns.h |
3 | * - adns user-visible API (single-threaded, without any locking) |
4 | */ |
5 | /* |
a719a4be |
6 | * This file is part of adns, which is Copyright (C) 1997-1999 Ian Jackson |
e576be50 |
7 | * |
8 | * This program is free software; you can redistribute it and/or modify |
9 | * it under the terms of the GNU General Public License as published by |
10 | * the Free Software Foundation; either version 2, or (at your option) |
11 | * any later version. |
12 | * |
13 | * This program is distributed in the hope that it will be useful, |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
16 | * GNU General Public License for more details. |
17 | * |
18 | * You should have received a copy of the GNU General Public License |
19 | * along with this program; if not, write to the Free Software Foundation, |
a719a4be |
20 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
21 | * |
22 | * $Id$ |
e576be50 |
23 | */ |
a17d3a1d |
24 | |
25 | #ifndef ADNS_H_INCLUDED |
26 | #define ADNS_H_INCLUDED |
27 | |
4353a5c4 |
28 | #include <stdio.h> |
29 | |
964344fc |
30 | #include <sys/socket.h> |
31 | #include <netinet/in.h> |
32 | |
09957b1c |
33 | /* All struct in_addr anywhere in adns are in NETWORK byte order. */ |
34 | |
964344fc |
35 | typedef struct adns__state *adns_state; |
36 | typedef struct adns__query *adns_query; |
a17d3a1d |
37 | |
38 | typedef enum { |
5ed1b7e7 |
39 | adns_if_noenv= 0x0001, /* do not look at environment */ |
40 | adns_if_noerrprint= 0x0002, /* never print output to stderr (_debug overrides) */ |
41 | adns_if_noserverwarn= 0x0004, /* do not warn to stderr about duff nameservers etc */ |
42 | adns_if_debug= 0x0008, /* enable all output to stderr plus debug msgs */ |
43 | adns_if_noautosys= 0x0010, /* do not make syscalls at every opportunity */ |
44 | adns_if_eintr= 0x0020, /* allow _wait and _synchronous to return EINTR */ |
45 | |
46 | /* Flags for address formatting, in both init and query. Do not use directly. */ |
47 | adns__iqaf_keepv4= 0x01000, /* If clear, any IPv4s will be mapped to AF_INET6 */ |
48 | adns__iqaf_weakv6= 0x02000, /* `Prefer IPv6 less' - depends on other flags */ |
49 | adns__iqaf_only= 0x04000, /* Return only one kind of address */ |
50 | adns__iqaf_override= 0x08000, /* In query flags, means to ignore init flags */ |
51 | adns__iqaf_mask= 0x07000, /* Mask of flags that _override overrides */ |
52 | |
53 | /* Actual address formatting options. These set the default. Do not combine them. |
54 | * Meanings are: |
55 | * _v6first: Query for AAAA; if no AAAA then query for A. Return all as AF_INET6. |
56 | * _v6first: Same, but return IPv6 as AF_INET6 and IPv4 as AF_INET. |
57 | * _both: Query for both A and AAAA, return all addresses as AF_INET6. |
58 | * _bothraw: Same, but return IPv6 as AF_INET6 and IPv4 as AF_INET. |
59 | * _v4only: Query only for A, and return as AF_INET. |
60 | * _v6only: Query only for AAAA, and return as AF_INET6. |
61 | * If none is specified, the default is _v6first. |
62 | */ |
63 | adns_if_addr_v6first= 0, |
64 | adns_if_addr_v6firstraw= adns__iqaf_keepv4, |
65 | adns_if_addr_both= adns__iqaf_weakv6, |
66 | adns_if_addr_bothraw= adns__iqaf_weakv6|adns__iqaf_keepv4, |
67 | adns_if_addr_v4only= adns__iqaf_only|adns__iqaf_weakv6|adns__iqaf_keepv4, |
68 | adns_if_addr_v6only= adns__iqaf_only, |
69 | |
70 | adns__if_internalmask= 0x7fff0000 |
a17d3a1d |
71 | } adns_initflags; |
72 | |
73 | typedef enum { |
5ed1b7e7 |
74 | adns_qf_search= 0x0000001, /* use the searchlist */ |
75 | adns_qf_usevc= 0x0000002, /* use a virtual circuit (TCP connection) */ |
76 | adns_qf_quoteok_query= 0x0000010, /* allow quote-requiring chars in query domain */ |
77 | adns_qf_quoteok_cname= 0x0000020, /* allow ... in CNAME we go via */ |
78 | adns_qf_quoteok_anshost= 0x0000040, /* allow ... in answers expected to be hostnames */ |
79 | adns_qf_cname_loose= 0x0000100, /* allow refs to CNAMEs - without, get _s_cname */ |
80 | adns_qf_cname_forbid= 0x0000200, /* don't follow CNAMEs, instead give _s_cname */ |
81 | |
82 | /* Address formatting options. They have the same meaning as the corresponding |
83 | * adns_if_... options. Do not combine with other _if_addr/_qf_addr options. |
84 | * If a _qf_addr is specified then the _if_addr are irrelevant, otherwise the |
85 | * _if_addr are used. |
86 | */ |
87 | adns_qf_addr_both= adns__iqaf_override|adns_if_addr_both, |
88 | adns_qf_addr_bothraw= adns__iqaf_override|adns_if_addr_bothraw, |
89 | adns_qf_addr_v6first= adns__iqaf_override|adns_if_addr_v6first, |
90 | adns_qf_addr_v6firstraw= adns__iqaf_override|adns_if_addr_v6firstraw, |
91 | adns_qf_addr_v4only= adns__iqaf_override|adns_if_addr_v4only, |
92 | adns_qf_addr_v6only= adns__iqaf_override|adns_if_addr_v6only, |
93 | |
94 | adns__qf_internalmask= 0x7fff0000 |
a17d3a1d |
95 | } adns_queryflags; |
96 | |
97 | typedef enum { |
5ed1b7e7 |
98 | adns__rrt_typemask= 0x0ffff, |
99 | adns__qtf_deref= 0x10000, /* dereference domains and perhaps produce extra data */ |
100 | adns__qtf_mail822= 0x20000, /* make mailboxes be in RFC822 rcpt field format */ |
101 | adns__qtf_nostdquery= 0x40000, /* do not make normal initial query */ |
102 | adns__qtf_mask= 0x07fff0000, |
ddfda861 |
103 | |
350d37d9 |
104 | adns_r_none= 0, |
ddfda861 |
105 | |
350d37d9 |
106 | adns_r_a= 1, |
ddfda861 |
107 | |
350d37d9 |
108 | adns_r_ns_raw= 2, |
109 | adns_r_ns= adns_r_ns_raw|adns__qtf_deref, |
ddfda861 |
110 | |
350d37d9 |
111 | adns_r_cname= 5, |
ddfda861 |
112 | |
350d37d9 |
113 | adns_r_soa_raw= 6, |
ddfda861 |
114 | adns_r_soa= adns_r_soa_raw|adns__qtf_mail822, |
ddfda861 |
115 | |
350d37d9 |
116 | adns_r_ptr_raw= 12, |
117 | adns_r_ptr= adns_r_ptr_raw|adns__qtf_deref, |
ddfda861 |
118 | |
350d37d9 |
119 | adns_r_hinfo= 13, |
ddfda861 |
120 | |
350d37d9 |
121 | adns_r_mx_raw= 15, |
122 | adns_r_mx= adns_r_mx_raw|adns__qtf_deref, |
ddfda861 |
123 | |
350d37d9 |
124 | adns_r_txt= 16, |
ddfda861 |
125 | |
350d37d9 |
126 | adns_r_rp_raw= 17, |
4353a5c4 |
127 | adns_r_rp= adns_r_rp_raw|adns__qtf_mail822, |
828d89bd |
128 | |
5ed1b7e7 |
129 | adns_r_aaaa= 28, |
130 | |
131 | adns_r_addr= adns_r_a|adns__qtf_nostdquery |
ddfda861 |
132 | |
a17d3a1d |
133 | } adns_rrtype; |
134 | |
964344fc |
135 | /* In queries without qtf_anyquote, all domains must have standard |
136 | * legal syntax. In queries _with_ qtf_anyquote, domains in the query |
137 | * or response may contain any characters, quoted according to |
138 | * RFC1035 5.1. On input to adns, the char* is a pointer to the |
139 | * interior of a " delimited string, except that " may appear in it, |
140 | * and on output, the char* is a pointer to a string which would be |
141 | * legal either inside or outside " delimiters, and any characters |
142 | * not usually legal in domain names will be quoted as \X |
143 | * (if the character is 33-126 except \ and ") or \DDD. |
144 | * |
ddfda861 |
145 | * Do not ask for _raw records containing mailboxes without |
146 | * specifying _qf_anyquote. |
964344fc |
147 | */ |
148 | |
a17d3a1d |
149 | typedef enum { |
150 | adns_s_ok, |
ea1e31e3 |
151 | |
152 | /* locally induced errors */ |
153 | adns_s_nomemory, |
154 | adns_s_unknownrrtype, |
155 | |
156 | /* remotely induced errors, detected locally */ |
37e28fde |
157 | adns_s_timeout, |
4bec51a4 |
158 | adns_s_allservfail, |
ec477b9e |
159 | adns_s_norecurse, |
ea1e31e3 |
160 | adns_s_invalidresponse, |
161 | adns_s_unknownformat, |
162 | |
163 | /* remotely induced errors, reported by remote server to us */ |
164 | adns_s_rcodeservfail, |
165 | adns_s_rcodeformaterror, |
166 | adns_s_rcodenotimplemented, |
167 | adns_s_rcoderefused, |
168 | adns_s_rcodeunknown, |
169 | |
b9de380c |
170 | adns_s_max_tempfail= 99, |
ea1e31e3 |
171 | |
172 | /* remote configuration errors */ |
173 | adns_s_inconsistent, /* PTR gives domain whose A does not exist and match */ |
174 | adns_s_prohibitedcname, /* CNAME found where eg A expected (not if _qf_loosecname) */ |
175 | adns_s_answerdomaininvalid, |
176 | adns_s_answerdomaintoolong, |
177 | adns_s_invaliddata, |
178 | |
179 | adns_s_max_misconfig= 199, |
180 | |
ea1e31e3 |
181 | /* permanent problems with the query */ |
182 | adns_s_querydomainwrong, |
183 | adns_s_querydomaininvalid, |
184 | adns_s_querydomaintoolong, |
185 | |
186 | adns_s_max_misquery= 299, |
187 | |
188 | /* permanent errors */ |
a17d3a1d |
189 | adns_s_nxdomain, |
0ba0614a |
190 | adns_s_nodata, |
ea1e31e3 |
191 | |
a17d3a1d |
192 | } adns_status; |
193 | |
e8c505a5 |
194 | typedef struct { |
828d89bd |
195 | int len; |
196 | union { |
197 | struct sockaddr sa; |
5ed1b7e7 |
198 | struct sockaddr_in inet; /* port field will be zero */ |
199 | struct sockaddr_in6 inet6; /* port field will be zero */ |
828d89bd |
200 | } addr; |
551ff40f |
201 | } adns_rr_addr; |
828d89bd |
202 | |
203 | typedef struct { |
1dfe95d8 |
204 | char *host; |
84fe28db |
205 | adns_status astatus; |
206 | int naddrs; /* temp fail => -1, perm fail => 0, s_ok => >0 */ |
551ff40f |
207 | adns_rr_addr *addrs; |
c7836bc9 |
208 | } adns_rr_hostaddr; |
4353a5c4 |
209 | |
210 | typedef struct { |
9ec44266 |
211 | char *(array[2]); |
4353a5c4 |
212 | } adns_rr_strpair; |
213 | |
214 | typedef struct { |
215 | int i; |
1dfe95d8 |
216 | adns_rr_hostaddr ha; |
c7836bc9 |
217 | } adns_rr_inthostaddr; |
4353a5c4 |
218 | |
219 | typedef struct { |
e062dcae |
220 | /* Used both for mx_raw, in which case i is the preference and str the domain, |
221 | * and for txt, in which case each entry has i for the `text' length, |
222 | * and str for the data (which will have had an extra nul appended |
223 | * so that if it was plain text it is now a null-terminated string). |
224 | */ |
4353a5c4 |
225 | int i; |
226 | char *str; |
227 | } adns_rr_intstr; |
228 | |
229 | typedef struct { |
9ec44266 |
230 | adns_rr_intstr array[2]; |
231 | } adns_rr_intstrpair; |
232 | |
233 | typedef struct { |
234 | char *mname, *rname; |
4353a5c4 |
235 | unsigned long serial, refresh, retry, expire, minimum; |
236 | } adns_rr_soa; |
84fe28db |
237 | |
238 | typedef struct { |
a17d3a1d |
239 | adns_status status; |
240 | char *cname; /* always NULL if query was for CNAME records */ |
86e7b8d9 |
241 | adns_rrtype type; /* guaranteed to be same as in query */ |
8e5b0abb |
242 | int nrrs, rrsz; |
a17d3a1d |
243 | union { |
8e5b0abb |
244 | void *untyped; |
245 | unsigned char *bytes; |
c7836bc9 |
246 | char *(*str); /* ns_raw, cname, ptr, ptr_raw */ |
247 | adns_rr_intstr *(*manyistr); /* txt (list of strings ends with i=-1, str=0) */ |
551ff40f |
248 | adns_rr_addr *addr; /* addr */ |
c7836bc9 |
249 | struct in_addr *inaddr; /* a */ |
5ed1b7e7 |
250 | struct in_addr6 *inaddr6; /* aaaa */ |
c7836bc9 |
251 | adns_rr_hostaddr *hostaddr; /* ns */ |
9ec44266 |
252 | adns_rr_intstrpair *intstrpair; /* hinfo */ |
253 | adns_rr_strpair *strpair; /* rp, rp_raw */ |
c7836bc9 |
254 | adns_rr_inthostaddr *inthostaddr; /* mx */ |
255 | adns_rr_intstr *intstr; /* mx_raw */ |
256 | adns_rr_soa *soa; /* soa, soa_raw */ |
a17d3a1d |
257 | } rrs; |
e8c505a5 |
258 | } adns_answer; |
a17d3a1d |
259 | |
260 | /* Memory management: |
261 | * adns_state and adns_query are actually pointers to malloc'd state; |
262 | * On submission questions are copied, including the owner domain; |
4353a5c4 |
263 | * Answers are malloc'd as a single piece of memory; pointers in the |
264 | * answer struct point into further memory in the answer. |
a17d3a1d |
265 | * query_io: |
266 | * Must always be non-null pointer; |
267 | * If *query_io is 0 to start with then any query may be returned; |
268 | * If *query_io is !0 adns_query then only that query may be returned. |
d3eea642 |
269 | * If the call is successful, *query_io, *answer_r, and *context_r |
270 | * will all be set. |
a17d3a1d |
271 | * Errors: |
272 | * Return values are 0 or an errno value; |
273 | * Seriously fatal system errors (eg, failure to create sockets, |
274 | * malloc failure, etc.) return errno values; |
275 | * Other errors (nameserver failure, timed out connections, &c) |
276 | * are returned in the status field of the answer. If status is |
277 | * nonzero then nrrs will be 0, otherwise it will be >0. |
278 | * type will always be the type requested; |
e8c505a5 |
279 | * If no (appropriate) requests are done adns_check returns EWOULDBLOCK; |
280 | * If no (appropriate) requests are outstanding adns_query and adns_wait return ESRCH; |
a17d3a1d |
281 | */ |
282 | |
36369543 |
283 | int adns_init(adns_state *newstate_r, adns_initflags flags, |
284 | FILE *diagfile /*0=>stderr*/); |
285 | |
286 | int adns_init_strcfg(adns_state *newstate_r, adns_initflags flags, |
287 | FILE *diagfile /*0=>discard*/, const char *configtext); |
a17d3a1d |
288 | |
289 | int adns_synchronous(adns_state ads, |
290 | const char *owner, |
291 | adns_rrtype type, |
72934832 |
292 | adns_queryflags flags, |
9d95094c |
293 | adns_answer **answer_r); |
e8c505a5 |
294 | |
295 | /* NB: if you set adns_if_noautosys then _submit and _check do not |
296 | * make any system calls; you must use adns_callback (possibly after |
297 | * adns_interest) to actually get things to happen. |
298 | */ |
a17d3a1d |
299 | |
300 | int adns_submit(adns_state ads, |
301 | const char *owner, |
302 | adns_rrtype type, |
72934832 |
303 | adns_queryflags flags, |
a17d3a1d |
304 | void *context, |
964344fc |
305 | adns_query *query_r); |
a17d3a1d |
306 | |
964344fc |
307 | int adns_check(adns_state ads, |
a17d3a1d |
308 | adns_query *query_io, |
9d95094c |
309 | adns_answer **answer_r, |
310 | void **context_r); |
a17d3a1d |
311 | |
312 | int adns_wait(adns_state ads, |
313 | adns_query *query_io, |
9d95094c |
314 | adns_answer **answer_r, |
315 | void **context_r); |
a719a4be |
316 | /* fixme: include TTL in answer somehow */ |
a719a4be |
317 | /* fixme: easy way to get lists of fd's */ |
18d49d56 |
318 | /* fixme: IPv6 */ |
a17d3a1d |
319 | |
3955725c |
320 | void adns_cancel(adns_query query); |
a17d3a1d |
321 | |
9ec44266 |
322 | void adns_finish(adns_state); |
e576be50 |
323 | /* You may call this even if you have queries outstanding; |
324 | * they will be cancelled. |
325 | */ |
a17d3a1d |
326 | |
e8c505a5 |
327 | int adns_callback(adns_state, int maxfd, const fd_set *readfds, const fd_set *writefds, |
328 | const fd_set *exceptfds); |
329 | /* Gives adns flow-of-control for a bit. This will never block. |
330 | * If maxfd == -1 then adns will check (make nonblocking system calls on) |
331 | * all of its own filedescriptors; otherwise it will only use those |
332 | * < maxfd and specified in the fd_set's, as if select had returned them. |
333 | * Other fd's may be in the fd_sets, and will be ignored. |
334 | * _callback returns how many adns fd's were in the various sets, so |
335 | * you can tell if your select handling code has missed something and is going awol. |
4353a5c4 |
336 | * |
337 | * May also return -1 if a critical syscall failed, setting errno. |
964344fc |
338 | */ |
339 | |
e8c505a5 |
340 | void adns_interest(adns_state, int *maxfd_io, fd_set *readfds_io, |
341 | fd_set *writefds_io, fd_set *exceptfds_io, |
342 | struct timeval **tv_mod, struct timeval *tv_buf); |
343 | /* Find out file descriptors adns is interested in, and when it |
344 | * would like the opportunity to time something out. If you do not plan to |
345 | * block then tv_mod may be 0. Otherwise, tv_mod may point to 0 meaning |
346 | * you have no timeout of your own, in which case tv_buf must be non-null and |
347 | * _interest may fill it in and set *tv_mod=tv_buf. |
348 | * readfds, writefds, exceptfds and maxfd may not be 0. |
964344fc |
349 | */ |
a17d3a1d |
350 | |
351 | /* Example expected/legal calling sequences: |
352 | * adns_init |
353 | * adns_submit 1 |
354 | * adns_submit 2 |
355 | * adns_submit 3 |
356 | * adns_wait 1 |
964344fc |
357 | * adns_check 3 -> EWOULDBLOCK |
a17d3a1d |
358 | * adns_wait 2 |
359 | * adns_wait 3 |
360 | * .... |
361 | * adns_finish |
362 | * |
e8c505a5 |
363 | * adns_init _noautosys |
a17d3a1d |
364 | * loop { |
a17d3a1d |
365 | * adns_interest |
366 | * select |
367 | * adns_callback |
e8c505a5 |
368 | * ... |
369 | * adns_submit / adns_check |
370 | * ... |
a17d3a1d |
371 | * } |
372 | */ |
373 | |
86e7b8d9 |
374 | adns_status adns_rr_info(adns_rrtype type, |
375 | const char **rrtname_r, const char **fmtname_r, |
376 | int *len_r, |
377 | const void *datap, char **data_r); |
378 | /* Gets information in human-readable (but non-i18n) form |
379 | * for eg debugging purposes. type must be specified, |
380 | * and the official name of the corresponding RR type will |
381 | * be returned in *rrtname_r, and information about the processing |
382 | * style in *fmtname_r. The length of the table entry in an answer |
383 | * for that type will be returned in in *len_r. |
384 | * Any or all of rrtname_r, fmtname_r and len_r may be 0. |
385 | * If fmtname_r is non-null then *fmtname_r may be |
386 | * null on return, indicating that no special processing is |
387 | * involved. |
388 | * |
389 | * data_r be must be non-null iff datap is. In this case |
390 | * *data_r will be set to point to a human-readable text |
391 | * string representing the RR data. The text will have |
392 | * been obtained from malloc() and must be freed by the caller. |
393 | * |
394 | * Usually this routine will succeed. Possible errors include: |
395 | * adns_s_nomemory |
ea1e31e3 |
396 | * adns_s_rrtypeunknown |
86e7b8d9 |
397 | * adns_s_invaliddata (*datap contained garbage) |
398 | * If an error occurs then no memory has been allocated, |
399 | * and *rrtname_r, *fmtname_r, *len_r and *data_r are undefined. |
400 | */ |
401 | |
31144a72 |
402 | const char *adns_strerror(adns_status st); |
403 | |
a17d3a1d |
404 | #endif |