2 * Copyright (C)1998 Ian Jackson.
3 * This version provided for review and comment only.
8 * This file is part of adns, which is Copyright (C) 1997, 1998 Ian Jackson
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2, or (at your option)
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software Foundation,
22 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
25 #ifndef ADNS_H_INCLUDED
26 #define ADNS_H_INCLUDED
30 #include <sys/socket.h>
31 #include <netinet/in.h>
33 typedef struct adns__state *adns_state;
34 typedef struct adns__query *adns_query;
37 adns_if_noenv= 0x0001, /* do not look at environment */
38 adns_if_noerrprint= 0x0002, /* never print output to stderr (_debug overrides) */
39 adns_if_noserverwarn= 0x0004, /* do not warn to stderr about duff nameservers etc */
40 adns_if_debug= 0x0008, /* enable all output to stderr plus debug msgs */
41 adns_if_noautosys= 0x0010, /* do not make syscalls at every opportunity */
45 adns_qf_search= 0x0001, /* use the searchlist */
46 adns_qf_usevc= 0x0002, /* use a virtual circuit (TCP connection) */
47 adns_qf_anyquote= 0x0004,
48 adns_qf_loosecname= 0x0008, /* allow refs to CNAMEs - without, get _s_cname */
49 adns_qf_nocname= 0x0010, /* don't follow CNAMEs, instead give _s_cname */
53 adns__rrt_typemask= 0x0ffff,
54 adns__qtf_deref= 0x10000, /* dereference domains and perhaps produce extra data */
55 adns__qtf_mail822= 0x20000, /* make mailboxes be in RFC822 rcpt field format */
62 adns_r_ns= adns_r_ns_raw|adns__qtf_deref,
67 adns_r_soa= adns_r_soa_raw|adns__qtf_mail822,
70 adns_r_ptr= adns_r_ptr_raw|adns__qtf_deref,
75 adns_r_mx= adns_r_mx_raw|adns__qtf_deref,
80 adns_r_rp= adns_r_rp_raw|adns__qtf_mail822,
84 /* In queries without qtf_anyquote, all domains must have standard
85 * legal syntax. In queries _with_ qtf_anyquote, domains in the query
86 * or response may contain any characters, quoted according to
87 * RFC1035 5.1. On input to adns, the char* is a pointer to the
88 * interior of a " delimited string, except that " may appear in it,
89 * and on output, the char* is a pointer to a string which would be
90 * legal either inside or outside " delimiters, and any characters
91 * not usually legal in domain names will be quoted as \X
92 * (if the character is 33-126 except \ and ") or \DDD.
94 * Do not ask for _raw records containing mailboxes without
95 * specifying _qf_anyquote.
104 adns_s_notimplemented,
106 adns_s_reasonunknown,
111 adns_s_max_tempfail= 99,
112 adns_s_inconsistent, /* PTR gives domain whose A does not match */
113 adns_s_cname, /* CNAME found where data eg A expected (not if _qf_loosecname) */
114 adns_s_invalidanswerdomain,
115 /* fixme: implement _s_cname */
116 adns_s_max_remotemisconfig= 199,
119 adns_s_invalidquerydomain,
120 adns_s_domaintoolong,
126 int naddrs; /* temp fail => -1, perm fail => 0, s_ok => >0 */
127 struct in_addr *addrs;
136 adns_rr_dmaddr dmaddr;
146 unsigned long serial, refresh, retry, expire, minimum;
151 char *cname; /* always NULL if query was for CNAME records */
152 adns_rrtype type; /* guaranteed to be same as in query */
156 unsigned char *bytes;
157 char *(*str); /* ns_raw, cname, ptr, ptr_raw */
158 char *(**manystr); /* txt (list is null-terminated) */
159 struct in_addr *inaddr; /* a */
160 adns_rr_dmaddr *dmaddr; /* ns */
161 adns_rr_strpair *strpair; /* hinfo, rp, rp_raw */
162 adns_rr_intdmaddr *intdmaddr; /* mx */
163 adns_rr_intstr *intstr; /* mx_raw */
164 adns_rr_soa *soa; /* soa, soa_raw */
168 /* Memory management:
169 * adns_state and adns_query are actually pointers to malloc'd state;
170 * On submission questions are copied, including the owner domain;
171 * Answers are malloc'd as a single piece of memory; pointers in the
172 * answer struct point into further memory in the answer.
174 * Must always be non-null pointer;
175 * If *query_io is 0 to start with then any query may be returned;
176 * If *query_io is !0 adns_query then only that query may be returned.
177 * If the call is successful, *query_io, *answer_r, and *context_r
180 * Return values are 0 or an errno value;
181 * Seriously fatal system errors (eg, failure to create sockets,
182 * malloc failure, etc.) return errno values;
183 * Other errors (nameserver failure, timed out connections, &c)
184 * are returned in the status field of the answer. If status is
185 * nonzero then nrrs will be 0, otherwise it will be >0.
186 * type will always be the type requested;
187 * If no (appropriate) requests are done adns_check returns EWOULDBLOCK;
188 * If no (appropriate) requests are outstanding adns_query and adns_wait return ESRCH;
191 int adns_init(adns_state *newstate_r, adns_initflags flags, FILE *diagfile/*0=>stderr*/);
193 int adns_synchronous(adns_state ads,
196 adns_queryflags flags,
197 adns_answer **answer_r);
198 /* Will not return EINTR. */
200 /* NB: if you set adns_if_noautosys then _submit and _check do not
201 * make any system calls; you must use adns_callback (possibly after
202 * adns_interest) to actually get things to happen.
205 int adns_submit(adns_state ads,
208 adns_queryflags flags,
210 adns_query *query_r);
212 int adns_check(adns_state ads,
213 adns_query *query_io,
214 adns_answer **answer_r,
217 int adns_wait(adns_state ads,
218 adns_query *query_io,
219 adns_answer **answer_r,
221 /* Might return EINTR - if so, try again */
223 void adns_cancel(adns_query query);
225 int adns_finish(adns_state);
226 /* You may call this even if you have queries outstanding;
227 * they will be cancelled.
230 int adns_callback(adns_state, int maxfd, const fd_set *readfds, const fd_set *writefds,
231 const fd_set *exceptfds);
232 /* Gives adns flow-of-control for a bit. This will never block.
233 * If maxfd == -1 then adns will check (make nonblocking system calls on)
234 * all of its own filedescriptors; otherwise it will only use those
235 * < maxfd and specified in the fd_set's, as if select had returned them.
236 * Other fd's may be in the fd_sets, and will be ignored.
237 * _callback returns how many adns fd's were in the various sets, so
238 * you can tell if your select handling code has missed something and is going awol.
240 * May also return -1 if a critical syscall failed, setting errno.
243 void adns_interest(adns_state, int *maxfd_io, fd_set *readfds_io,
244 fd_set *writefds_io, fd_set *exceptfds_io,
245 struct timeval **tv_mod, struct timeval *tv_buf);
246 /* Find out file descriptors adns is interested in, and when it
247 * would like the opportunity to time something out. If you do not plan to
248 * block then tv_mod may be 0. Otherwise, tv_mod may point to 0 meaning
249 * you have no timeout of your own, in which case tv_buf must be non-null and
250 * _interest may fill it in and set *tv_mod=tv_buf.
251 * readfds, writefds, exceptfds and maxfd may not be 0.
254 /* Example expected/legal calling sequences:
260 * adns_check 3 -> EWOULDBLOCK
266 * adns_init _noautosys
272 * adns_submit / adns_check
277 adns_status adns_rr_info(adns_rrtype type,
278 const char **rrtname_r, const char **fmtname_r,
280 const void *datap, char **data_r);
281 /* Gets information in human-readable (but non-i18n) form
282 * for eg debugging purposes. type must be specified,
283 * and the official name of the corresponding RR type will
284 * be returned in *rrtname_r, and information about the processing
285 * style in *fmtname_r. The length of the table entry in an answer
286 * for that type will be returned in in *len_r.
287 * Any or all of rrtname_r, fmtname_r and len_r may be 0.
288 * If fmtname_r is non-null then *fmtname_r may be
289 * null on return, indicating that no special processing is
292 * data_r be must be non-null iff datap is. In this case
293 * *data_r will be set to point to a human-readable text
294 * string representing the RR data. The text will have
295 * been obtained from malloc() and must be freed by the caller.
297 * Usually this routine will succeed. Possible errors include:
299 * adns_s_notimplemented (RR type not known)
300 * adns_s_invaliddata (*datap contained garbage)
301 * If an error occurs then no memory has been allocated,
302 * and *rrtname_r, *fmtname_r, *len_r and *data_r are undefined.
305 const char *adns_strerror(adns_status st);