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, txt */
158 struct in_addr
*inaddr
; /* a */
159 adns_rr_dmaddr
*dmaddr
; /* ns */
160 adns_rr_strpair
*strpair
; /* hinfo, rp, rp_raw */
161 adns_rr_intdmaddr
*intdmaddr
; /* mx */
162 adns_rr_intstr
*intstr
; /* mx_raw */
163 adns_rr_soa
*soa
; /* soa, soa_raw */
167 /* Memory management:
168 * adns_state and adns_query are actually pointers to malloc'd state;
169 * On submission questions are copied, including the owner domain;
170 * Answers are malloc'd as a single piece of memory; pointers in the
171 * answer struct point into further memory in the answer.
173 * Must always be non-null pointer;
174 * If *query_io is 0 to start with then any query may be returned;
175 * If *query_io is !0 adns_query then only that query may be returned.
176 * If the call is successful, *query_io, *answer_r, and *context_r
179 * Return values are 0 or an errno value;
180 * Seriously fatal system errors (eg, failure to create sockets,
181 * malloc failure, etc.) return errno values;
182 * Other errors (nameserver failure, timed out connections, &c)
183 * are returned in the status field of the answer. If status is
184 * nonzero then nrrs will be 0, otherwise it will be >0.
185 * type will always be the type requested;
186 * If no (appropriate) requests are done adns_check returns EWOULDBLOCK;
187 * If no (appropriate) requests are outstanding adns_query and adns_wait return ESRCH;
190 int adns_init(adns_state
*newstate_r
, adns_initflags flags
, FILE *diagfile
/*0=>stderr*/);
192 int adns_synchronous(adns_state ads
,
195 adns_queryflags flags
,
196 adns_answer
**answer_r
);
197 /* Will not return EINTR. */
199 /* NB: if you set adns_if_noautosys then _submit and _check do not
200 * make any system calls; you must use adns_callback (possibly after
201 * adns_interest) to actually get things to happen.
204 int adns_submit(adns_state ads
,
207 adns_queryflags flags
,
209 adns_query
*query_r
);
211 int adns_check(adns_state ads
,
212 adns_query
*query_io
,
213 adns_answer
**answer_r
,
216 int adns_wait(adns_state ads
,
217 adns_query
*query_io
,
218 adns_answer
**answer_r
,
220 /* Might return EINTR - if so, try again */
222 void adns_cancel(adns_query query
);
224 int adns_finish(adns_state
);
225 /* You may call this even if you have queries outstanding;
226 * they will be cancelled.
229 int adns_callback(adns_state
, int maxfd
, const fd_set
*readfds
, const fd_set
*writefds
,
230 const fd_set
*exceptfds
);
231 /* Gives adns flow-of-control for a bit. This will never block.
232 * If maxfd == -1 then adns will check (make nonblocking system calls on)
233 * all of its own filedescriptors; otherwise it will only use those
234 * < maxfd and specified in the fd_set's, as if select had returned them.
235 * Other fd's may be in the fd_sets, and will be ignored.
236 * _callback returns how many adns fd's were in the various sets, so
237 * you can tell if your select handling code has missed something and is going awol.
239 * May also return -1 if a critical syscall failed, setting errno.
242 void adns_interest(adns_state
, int *maxfd_io
, fd_set
*readfds_io
,
243 fd_set
*writefds_io
, fd_set
*exceptfds_io
,
244 struct timeval
**tv_mod
, struct timeval
*tv_buf
);
245 /* Find out file descriptors adns is interested in, and when it
246 * would like the opportunity to time something out. If you do not plan to
247 * block then tv_mod may be 0. Otherwise, tv_mod may point to 0 meaning
248 * you have no timeout of your own, in which case tv_buf must be non-null and
249 * _interest may fill it in and set *tv_mod=tv_buf.
250 * readfds, writefds, exceptfds and maxfd may not be 0.
253 /* Example expected/legal calling sequences:
259 * adns_check 3 -> EWOULDBLOCK
265 * adns_init _noautosys
271 * adns_submit / adns_check
276 adns_status
adns_rr_info(adns_rrtype type
,
277 const char **rrtname_r
, const char **fmtname_r
,
279 const void *datap
, char **data_r
);
280 /* Gets information in human-readable (but non-i18n) form
281 * for eg debugging purposes. type must be specified,
282 * and the official name of the corresponding RR type will
283 * be returned in *rrtname_r, and information about the processing
284 * style in *fmtname_r. The length of the table entry in an answer
285 * for that type will be returned in in *len_r.
286 * Any or all of rrtname_r, fmtname_r and len_r may be 0.
287 * If fmtname_r is non-null then *fmtname_r may be
288 * null on return, indicating that no special processing is
291 * data_r be must be non-null iff datap is. In this case
292 * *data_r will be set to point to a human-readable text
293 * string representing the RR data. The text will have
294 * been obtained from malloc() and must be freed by the caller.
296 * Usually this routine will succeed. Possible errors include:
298 * adns_s_notimplemented (RR type not known)
299 * adns_s_invaliddata (*datap contained garbage)
300 * If an error occurs then no memory has been allocated,
301 * and *rrtname_r, *fmtname_r, *len_r and *data_r are undefined.
304 const char *adns_strerror(adns_status st
);