e576be50 |
1 | /* |
2 | * internal.h |
3 | * - declarations of private objects with external linkage (adns__*) |
4 | * - definitons of internal macros |
5 | * - comments regarding library data structures |
6 | */ |
7 | /* |
d942707d |
8 | * This file is |
3d5cde09 |
9 | * Copyright (C) 1997-2000 Ian Jackson <ian@davenant.greenend.org.uk> |
d942707d |
10 | * |
11 | * It is part of adns, which is |
3d5cde09 |
12 | * Copyright (C) 1997-2000 Ian Jackson <ian@davenant.greenend.org.uk> |
bef232ae |
13 | * Copyright (C) 1999-2000 Tony Finch <dot@dotat.at> |
f7f83b4a |
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. |
f7f83b4a |
19 | * |
e576be50 |
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. |
f7f83b4a |
24 | * |
e576be50 |
25 | * You should have received a copy of the GNU General Public License |
26 | * along with this program; if not, write to the Free Software Foundation, |
f7f83b4a |
27 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
e576be50 |
28 | */ |
37e28fde |
29 | |
30 | #ifndef ADNS_INTERNAL_H_INCLUDED |
31 | #define ADNS_INTERNAL_H_INCLUDED |
32 | |
11b35193 |
33 | #include "config.h" |
4353a5c4 |
34 | typedef unsigned char byte; |
35 | |
36 | #include <stdarg.h> |
37 | #include <assert.h> |
38 | #include <unistd.h> |
ac868fa8 |
39 | #include <signal.h> |
620c146d |
40 | #include <errno.h> |
b365d68a |
41 | #include <string.h> |
0d66e373 |
42 | #include <stdlib.h> |
4353a5c4 |
43 | |
37e28fde |
44 | #include <sys/time.h> |
45 | |
46 | #include "adns.h" |
70ad7a2a |
47 | #include "dlist.h" |
37e28fde |
48 | |
0ebff22d |
49 | #ifdef ADNS_REGRESS_TEST |
50 | # include "hredirect.h" |
51 | #endif |
52 | |
37e28fde |
53 | /* Configuration and constants */ |
54 | |
55 | #define MAXSERVERS 5 |
09957b1c |
56 | #define MAXSORTLIST 15 |
4b707d8b |
57 | #define UDPMAXRETRIES 15 |
37e28fde |
58 | #define UDPRETRYMS 2000 |
f7f83b4a |
59 | #define TCPWAITMS 30000 |
60 | #define TCPCONNMS 14000 |
61 | #define TCPIDLEMS 30000 |
73dba56e |
62 | #define MAXTTLBELIEVE (7*86400) /* any TTL > 7 days is capped */ |
b9de380c |
63 | |
98a3f706 |
64 | #define DNS_PORT 53 |
b9de380c |
65 | #define DNS_MAXUDP 512 |
5b9dd636 |
66 | #define DNS_MAXLABEL 63 |
b9de380c |
67 | #define DNS_MAXDOMAIN 255 |
68 | #define DNS_HDRSIZE 12 |
660d7d3b |
69 | #define DNS_IDOFFSET 0 |
b9de380c |
70 | #define DNS_CLASS_IN 1 |
37e28fde |
71 | |
a6536d8b |
72 | #define DNS_INADDR_ARPA "in-addr", "arpa" |
73 | |
620c146d |
74 | #define MAX_POLLFDS ADNS_POLLFDS_RECOMMENDED |
75 | |
98a3f706 |
76 | typedef enum { |
3e2e5fab |
77 | cc_user, |
78 | cc_entex, |
79 | cc_freq |
80 | } consistency_checks; |
81 | |
82 | typedef enum { |
98a3f706 |
83 | rcode_noerror, |
84 | rcode_formaterror, |
85 | rcode_servfail, |
86 | rcode_nxdomain, |
87 | rcode_notimp, |
88 | rcode_refused |
89 | } dns_rcode; |
90 | |
37e28fde |
91 | /* Shared data structures */ |
92 | |
4353a5c4 |
93 | typedef union { |
37e28fde |
94 | adns_status status; |
95 | char *cp; |
96 | adns_rrtype type; |
4353a5c4 |
97 | int i; |
37e28fde |
98 | struct in_addr ia; |
99 | unsigned long ul; |
4353a5c4 |
100 | } rr_align; |
101 | |
102 | typedef struct { |
103 | int used, avail; |
104 | byte *buf; |
105 | } vbuf; |
106 | |
0ba0614a |
107 | typedef struct { |
1dfe95d8 |
108 | adns_state ads; |
c7836bc9 |
109 | adns_query qu; |
1dfe95d8 |
110 | int serv; |
c7836bc9 |
111 | const byte *dgram; |
1dfe95d8 |
112 | int dglen, nsstart, nscount, arcount; |
7da21070 |
113 | struct timeval now; |
c7836bc9 |
114 | } parseinfo; |
115 | |
d19b03d0 |
116 | typedef struct typeinfo { |
0ba0614a |
117 | adns_rrtype type; |
86e7b8d9 |
118 | const char *rrtname; |
119 | const char *fmtname; |
98a3f706 |
120 | int rrsz; |
8e5b0abb |
121 | |
86e7b8d9 |
122 | void (*makefinal)(adns_query qu, void *data); |
123 | /* Change memory management of *data. |
124 | * Previously, used alloc_interim, now use alloc_final. |
125 | */ |
126 | |
127 | adns_status (*convstring)(vbuf *vb, const void *data); |
128 | /* Converts the RR data to a string representation in vbuf. |
129 | * vbuf will be appended to (it must have been initialised), |
130 | * and will not be null-terminated by convstring. |
131 | */ |
132 | |
609133ee |
133 | adns_status (*parse)(const parseinfo *pai, int cbyte, |
134 | int max, void *store_r); |
31144a72 |
135 | /* Parse one RR, in dgram of length dglen, starting at cbyte and |
136 | * extending until at most max. |
137 | * |
138 | * The RR should be stored at *store_r, of length qu->typei->rrsz. |
139 | * |
140 | * If there is an overrun which might indicate truncation, it should set |
141 | * *rdstart to -1; otherwise it may set it to anything else positive. |
88372443 |
142 | * |
c7836bc9 |
143 | * nsstart is the offset of the authority section. |
8e5b0abb |
144 | */ |
e062dcae |
145 | |
609133ee |
146 | int (*diff_needswap)(adns_state ads,const void *datap_a,const void *datap_b); |
88372443 |
147 | /* Returns !0 if RR a should be strictly after RR b in the sort order, |
e062dcae |
148 | * 0 otherwise. Must not fail. |
149 | */ |
d19b03d0 |
150 | |
151 | adns_status (*qdparselabel)(adns_state ads, |
152 | const char **p_io, const char *pe, int labelnum, |
153 | char label_r[DNS_MAXDOMAIN], int *ll_io, |
154 | adns_queryflags flags, |
155 | const struct typeinfo *typei); |
156 | /* Parses one label from the query domain string. On entry, *p_io |
157 | * points to the next character to parse and *ll_io is the size of |
158 | * the buffer. pe points just after the end of the query domain |
159 | * string. On successful return, label_r[] and *ll_io are filled in |
160 | * and *p_io points to *pe or just after the label-ending `.'. */ |
161 | |
0e45654b |
162 | void (*postsort)(adns_state ads, void *array, int nrrs, |
d24e2a7e |
163 | const struct typeinfo *typei); |
164 | /* Called immediately after the RRs have been sorted, and may rearrange |
165 | * them. (This is really for the benefit of SRV's bizarre weighting |
166 | * stuff.) May be 0 to mean nothing needs to be done. |
167 | */ |
0ba0614a |
168 | } typeinfo; |
169 | |
d19b03d0 |
170 | adns_status adns__qdpl_normal(adns_state ads, |
171 | const char **p_io, const char *pe, int labelnum, |
172 | char label_r[], int *ll_io, |
173 | adns_queryflags flags, |
174 | const typeinfo *typei); |
175 | /* implemented in transmit.c, used by types.c as default |
176 | * and as part of implementation for some fancier types */ |
177 | |
8e5b0abb |
178 | typedef struct allocnode { |
551ff40f |
179 | struct allocnode *next, *back; |
8e5b0abb |
180 | } allocnode; |
181 | |
182 | union maxalign { |
183 | byte d[1]; |
184 | struct in_addr ia; |
185 | long l; |
186 | void *p; |
187 | void (*fp)(void); |
188 | union maxalign *up; |
189 | } data; |
190 | |
a6536d8b |
191 | typedef struct { |
192 | void *ext; |
193 | void (*callback)(adns_query parent, adns_query child); |
194 | union { |
195 | adns_rr_addr ptr_parent_addr; |
196 | adns_rr_hostaddr *hostaddr; |
197 | } info; |
198 | } qcontext; |
199 | |
37e28fde |
200 | struct adns__query { |
3955725c |
201 | adns_state ads; |
f7f83b4a |
202 | enum { query_tosend, query_tcpw, query_childw, query_done } state; |
4353a5c4 |
203 | adns_query back, next, parent; |
37e28fde |
204 | struct { adns_query head, tail; } children; |
205 | struct { adns_query back, next; } siblings; |
551ff40f |
206 | struct { allocnode *head, *tail; } allocations; |
8b3d55e3 |
207 | int interim_allocd, preserved_allocd; |
68442019 |
208 | void *final_allocspace; |
8ce38e76 |
209 | |
0ba0614a |
210 | const typeinfo *typei; |
e062dcae |
211 | byte *query_dgram; |
8e5b0abb |
212 | int query_dglen; |
f7f83b4a |
213 | |
8e5b0abb |
214 | vbuf vb; |
215 | /* General-purpose messing-about buffer. |
216 | * Wherever a `big' interface is crossed, this may be corrupted/changed |
217 | * unless otherwise specified. |
218 | */ |
219 | |
220 | adns_answer *answer; |
221 | /* This is allocated when a query is submitted, to avoid being unable |
222 | * to relate errors to queries if we run out of memory. During |
223 | * query processing status, rrs is 0. cname is set if |
224 | * we found a cname (this corresponds to cname_dgram in the query |
225 | * structure). type is set from the word go. nrrs and rrs |
226 | * are set together, when we find how many rrs there are. |
22181a31 |
227 | * owner is set during querying unless we're doing searchlist, |
228 | * in which case it is set only when we find an answer. |
8e5b0abb |
229 | */ |
f7f83b4a |
230 | |
31144a72 |
231 | byte *cname_dgram; |
232 | int cname_dglen, cname_begin; |
3955725c |
233 | /* If non-0, has been allocated using . */ |
32af6b2a |
234 | |
235 | vbuf search_vb; |
236 | int search_origlen, search_pos, search_doneabs; |
237 | /* Used by the searching algorithm. The query domain in textual form |
238 | * is copied into the vbuf, and _origlen set to its length. Then |
239 | * we walk the searchlist, if we want to. _pos says where we are |
240 | * (next entry to try), and _doneabs says whether we've done the |
660d7d3b |
241 | * absolute query yet (0=not yet, 1=done, -1=must do straight away, |
242 | * but not done yet). If flags doesn't have adns_qf_search then |
32af6b2a |
243 | * the vbuf is initialised but empty and everything else is zero. |
32af6b2a |
244 | */ |
f7f83b4a |
245 | |
246 | int id, flags, retries; |
4353a5c4 |
247 | int udpnextserver; |
f7f83b4a |
248 | unsigned long udpsent; /* bitmap indexed by server */ |
37e28fde |
249 | struct timeval timeout; |
73dba56e |
250 | time_t expires; /* Earliest expiry time of any record we used. */ |
a6536d8b |
251 | |
252 | qcontext ctx; |
ddfda861 |
253 | |
37e28fde |
254 | /* Possible states: |
ddfda861 |
255 | * |
3e2e5fab |
256 | * state Queue child id nextudpserver udpsent tcpfailed |
f7f83b4a |
257 | * |
d8c062fa |
258 | * tosend NONE null >=0 0 zero zero |
f7f83b4a |
259 | * tosend udpw null >=0 any nonzero zero |
d8c062fa |
260 | * tosend NONE null >=0 any nonzero zero |
f7f83b4a |
261 | * |
262 | * tcpw tcpw null >=0 irrelevant any any |
263 | * |
8e5b0abb |
264 | * child childw set >=0 irrelevant irrelevant irrelevant |
dcc8e442 |
265 | * child NONE null >=0 irrelevant irrelevant irrelevant |
8e5b0abb |
266 | * done output null -1 irrelevant irrelevant irrelevant |
ddfda861 |
267 | * |
dcc8e442 |
268 | * Queries are only not on a queue when they are actually being processed. |
f7f83b4a |
269 | * Queries in state tcpw/tcpw have been sent (or are in the to-send buffer) |
270 | * iff the tcp connection is in state server_ok. |
dcc8e442 |
271 | * |
ddfda861 |
272 | * +------------------------+ |
f7f83b4a |
273 | * START -----> | tosend/NONE | |
ddfda861 |
274 | * +------------------------+ |
275 | * / |\ \ |
276 | * too big for UDP / UDP timeout \ \ send via UDP |
f7f83b4a |
277 | * send via TCP / more retries \ \ |
278 | * when conn'd / desired \ \ |
279 | * | | | |
280 | * v | v |
281 | * +-----------+ +-------------+ |
282 | * | tcpw/tcpw | ________ | tosend/udpw | |
283 | * +-----------+ \ +-------------+ |
284 | * | | | UDP timeout | | |
285 | * | | | no more | | |
286 | * | | | retries | | |
287 | * \ | TCP died | desired | | |
288 | * \ \ no more | | | |
289 | * \ \ servers | TCP / | |
290 | * \ \ to try | timeout / | |
291 | * got \ \ v |_ | got |
ddfda861 |
292 | * reply \ _| +------------------+ / reply |
293 | * \ | done/output FAIL | / |
294 | * \ +------------------+ / |
295 | * \ / |
296 | * _| |_ |
297 | * (..... got reply ....) |
298 | * / \ |
299 | * need child query/ies / \ no child query |
300 | * / \ |
301 | * |_ _| |
f7f83b4a |
302 | * +---------------+ +----------------+ |
303 | * | childw/childw | ----------------> | done/output OK | |
304 | * +---------------+ children done +----------------+ |
37e28fde |
305 | */ |
306 | }; |
307 | |
f7f83b4a |
308 | struct query_queue { adns_query head, tail; }; |
309 | |
37e28fde |
310 | struct adns__state { |
37e28fde |
311 | adns_initflags iflags; |
d3a102c4 |
312 | adns_logcallbackfn *logfn; |
313 | void *logfndata; |
36369543 |
314 | int configerrno; |
f7f83b4a |
315 | struct query_queue udpw, tcpw, childw, output; |
8ce38e76 |
316 | adns_query forallnext; |
4353a5c4 |
317 | int nextid, udpsocket, tcpsocket; |
8e5b0abb |
318 | vbuf tcpsend, tcprecv; |
70ad7a2a |
319 | int nservers, nsortlist, nsearchlist, searchndots, tcpserver, tcprecv_skip; |
f7f83b4a |
320 | enum adns__tcpstate { |
321 | server_disconnected, server_connecting, |
322 | server_ok, server_broken |
323 | } tcpstate; |
37e28fde |
324 | struct timeval tcptimeout; |
4fad263d |
325 | /* This will have tv_sec==0 if it is not valid. It will always be |
326 | * valid if tcpstate _connecting. When _ok, it will be nonzero if |
327 | * we are idle (ie, tcpw queue is empty), in which case it is the |
328 | * absolute time when we will close the connection. |
f7f83b4a |
329 | */ |
ac868fa8 |
330 | struct sigaction stdsigpipe; |
331 | sigset_t stdsigmask; |
620c146d |
332 | struct pollfd pollfds_buf[MAX_POLLFDS]; |
37e28fde |
333 | struct server { |
334 | struct in_addr addr; |
335 | } servers[MAXSERVERS]; |
09957b1c |
336 | struct sortlist { |
337 | struct in_addr base, mask; |
338 | } sortlist[MAXSORTLIST]; |
32af6b2a |
339 | char **searchlist; |
0e45654b |
340 | unsigned short rand48xsubi[3]; |
37e28fde |
341 | }; |
342 | |
343 | /* From setup.c: */ |
344 | |
e576be50 |
345 | int adns__setnonblock(adns_state ads, int fd); /* => errno value */ |
346 | |
347 | /* From general.c: */ |
348 | |
d3a102c4 |
349 | void adns__vlprintf(adns_state ads, const char *fmt, va_list al); |
350 | void adns__lprintf(adns_state ads, const char *fmt, |
351 | ...) PRINTFFORMAT(2,3); |
352 | |
4353a5c4 |
353 | void adns__vdiag(adns_state ads, const char *pfx, adns_initflags prevent, |
68442019 |
354 | int serv, adns_query qu, const char *fmt, va_list al); |
31144a72 |
355 | |
356 | void adns__debug(adns_state ads, int serv, adns_query qu, |
68442019 |
357 | const char *fmt, ...) PRINTFFORMAT(4,5); |
31144a72 |
358 | void adns__warn(adns_state ads, int serv, adns_query qu, |
68442019 |
359 | const char *fmt, ...) PRINTFFORMAT(4,5); |
31144a72 |
360 | void adns__diag(adns_state ads, int serv, adns_query qu, |
68442019 |
361 | const char *fmt, ...) PRINTFFORMAT(4,5); |
37e28fde |
362 | |
4353a5c4 |
363 | int adns__vbuf_ensure(vbuf *vb, int want); |
609133ee |
364 | int adns__vbuf_appendstr(vbuf *vb, const char *data); /* doesn't include nul */ |
4353a5c4 |
365 | int adns__vbuf_append(vbuf *vb, const byte *data, int len); |
ddfda861 |
366 | /* 1=>success, 0=>realloc failed */ |
4353a5c4 |
367 | void adns__vbuf_appendq(vbuf *vb, const byte *data, int len); |
368 | void adns__vbuf_init(vbuf *vb); |
8e5b0abb |
369 | void adns__vbuf_free(vbuf *vb); |
4353a5c4 |
370 | |
828d89bd |
371 | const char *adns__diag_domain(adns_state ads, int serv, adns_query qu, |
609133ee |
372 | vbuf *vb, |
373 | const byte *dgram, int dglen, int cbyte); |
e576be50 |
374 | /* Unpicks a domain in a datagram and returns a string suitable for |
375 | * printing it as. Never fails - if an error occurs, it will |
376 | * return some kind of string describing the error. |
377 | * |
3955725c |
378 | * serv may be -1 and qu may be 0. vb must have been initialised, |
e576be50 |
379 | * and will be left in an arbitrary consistent state. |
380 | * |
381 | * Returns either vb->buf, or a pointer to a string literal. Do not modify |
382 | * vb before using the return value. |
383 | */ |
f7f83b4a |
384 | |
88372443 |
385 | void adns__isort(void *array, int nobjs, int sz, void *tempbuf, |
09957b1c |
386 | int (*needswap)(void *context, const void *a, const void *b), |
387 | void *context); |
88372443 |
388 | /* Does an insertion sort of array which must contain nobjs objects |
389 | * each sz bytes long. tempbuf must point to a buffer at least |
390 | * sz bytes long. needswap should return !0 if a>b (strictly, ie |
391 | * wrong order) 0 if a<=b (ie, order is fine). |
392 | */ |
ac868fa8 |
393 | |
394 | void adns__sigpipe_protect(adns_state); |
395 | void adns__sigpipe_unprotect(adns_state); |
396 | /* If SIGPIPE protection is not disabled, will block all signals except |
397 | * SIGPIPE, and set SIGPIPE's disposition to SIG_IGN. (And then restore.) |
398 | * Each call to _protect must be followed by a call to _unprotect before |
1f2ababa |
399 | * any significant amount of code gets to run, since the old signal mask |
400 | * is stored in the adns structure. |
ac868fa8 |
401 | */ |
402 | |
e576be50 |
403 | /* From transmit.c: */ |
ddfda861 |
404 | |
3955725c |
405 | adns_status adns__mkquery(adns_state ads, vbuf *vb, int *id_r, |
406 | const char *owner, int ol, |
e576be50 |
407 | const typeinfo *typei, adns_queryflags flags); |
660d7d3b |
408 | /* Assembles a query packet in vb. A new id is allocated and returned. |
409 | */ |
e576be50 |
410 | |
e062dcae |
411 | adns_status adns__mkquery_frdgram(adns_state ads, vbuf *vb, int *id_r, |
609133ee |
412 | const byte *qd_dgram, int qd_dglen, |
413 | int qd_begin, |
e062dcae |
414 | adns_rrtype type, adns_queryflags flags); |
415 | /* Same as adns__mkquery, but takes the owner domain from an existing datagram. |
416 | * That domain must be correct and untruncated. |
417 | */ |
418 | |
f7f83b4a |
419 | void adns__querysend_tcp(adns_query qu, struct timeval now); |
420 | /* Query must be in state tcpw/tcpw; it will be sent if possible and |
421 | * no further processing can be done on it for now. The connection |
422 | * might be broken, but no reconnect will be attempted. |
e576be50 |
423 | */ |
424 | |
d8c062fa |
425 | void adns__query_send(adns_query qu, struct timeval now); |
426 | /* Query must be in state tosend/NONE; it will be moved to a new state, |
e576be50 |
427 | * and no further processing can be done on it for now. |
609133ee |
428 | * (Resulting state is one of udp/timew, tcpwait/timew (if server not |
429 | * connected), tcpsent/timew, child/childw or done/output.) |
d8c062fa |
430 | * __query_send may decide to use either UDP or TCP depending whether |
431 | * _qf_usevc is set (or has become set) and whether the query is too |
432 | * large. |
e576be50 |
433 | */ |
434 | |
435 | /* From query.c: */ |
37e28fde |
436 | |
660d7d3b |
437 | adns_status adns__internal_submit(adns_state ads, adns_query *query_r, |
609133ee |
438 | const typeinfo *typei, vbuf *qumsg_vb, |
439 | int id, |
660d7d3b |
440 | adns_queryflags flags, struct timeval now, |
441 | const qcontext *ctx); |
8e5b0abb |
442 | /* Submits a query (for internal use, called during external submits). |
443 | * |
444 | * The new query is returned in *query_r, or we return adns_s_nomemory. |
445 | * |
68442019 |
446 | * The query datagram should already have been assembled in qumsg_vb; |
447 | * the memory for it is _taken over_ by this routine whether it |
448 | * succeeds or fails (if it succeeds, the vbuf is reused for qu->vb). |
8e5b0abb |
449 | * |
7da21070 |
450 | * *ctx is copied byte-for-byte into the query. |
dcc8e442 |
451 | * |
452 | * When the child query is done, ctx->callback will be called. The |
453 | * child will already have been taken off both the global list of |
454 | * queries in ads and the list of children in the parent. The child |
455 | * will be freed when the callback returns. The parent will have been |
4218fb9a |
456 | * taken off the global childw queue. |
457 | * |
458 | * The callback should either call adns__query_done, if it is |
459 | * complete, or adns__query_fail, if an error has occurred, in which |
460 | * case the other children (if any) will be cancelled. If the parent |
461 | * has more unfinished children (or has just submitted more) then the |
462 | * callback may choose to wait for them - it must then put the parent |
463 | * back on the childw queue. |
8e5b0abb |
464 | */ |
465 | |
660d7d3b |
466 | void adns__search_next(adns_state ads, adns_query qu, struct timeval now); |
467 | /* Walks down the searchlist for a query with adns_qf_search. |
468 | * The query should have just had a negative response, or not had |
469 | * any queries sent yet, and should not be on any queue. |
470 | * The query_dgram if any will be freed and forgotten and a new |
471 | * one constructed from the search_* members of the query. |
472 | * |
473 | * Cannot fail (in case of error, calls adns__query_fail). |
474 | */ |
475 | |
8e5b0abb |
476 | void *adns__alloc_interim(adns_query qu, size_t sz); |
8b3d55e3 |
477 | void *adns__alloc_preserved(adns_query qu, size_t sz); |
8e5b0abb |
478 | /* Allocates some memory, and records which query it came from |
479 | * and how much there was. |
480 | * |
8b3d55e3 |
481 | * If an error occurs in the query, all the memory from _interim is |
482 | * simply freed. If the query succeeds, one large buffer will be made |
483 | * which is big enough for all these allocations, and then |
484 | * adns__alloc_final will get memory from this buffer. |
8e5b0abb |
485 | * |
e062dcae |
486 | * _alloc_interim can fail (and return 0). |
487 | * The caller must ensure that the query is failed. |
a49a6d7b |
488 | * |
8b3d55e3 |
489 | * The memory from _preserved is is kept and transferred into the |
490 | * larger buffer - unless we run out of memory, in which case it too |
491 | * is freed. When you use _preserved you have to add code to the |
492 | * x_nomem error exit case in adns__makefinal_query to clear out the |
493 | * pointers you made to those allocations, because that's when they're |
494 | * thrown away; you should also make a note in the declaration of |
495 | * those pointer variables, to note that they are _preserved rather |
496 | * than _interim. If they're in the answer, note it here: |
497 | * answer->cname and answer->owner are _preserved. |
8e5b0abb |
498 | */ |
499 | |
609133ee |
500 | void adns__transfer_interim(adns_query from, adns_query to, |
501 | void *block, size_t sz); |
551ff40f |
502 | /* Transfers an interim allocation from one query to another, so that |
503 | * the `to' query will have room for the data when we get to makefinal |
504 | * and so that the free will happen when the `to' query is freed |
505 | * rather than the `from' query. |
506 | * |
507 | * It is legal to call adns__transfer_interim with a null pointer; this |
508 | * has no effect. |
73dba56e |
509 | * |
510 | * _transfer_interim also ensures that the expiry time of the `to' query |
511 | * is no later than that of the `from' query, so that child queries' |
512 | * TTLs get inherited by their parents. |
551ff40f |
513 | */ |
514 | |
3955725c |
515 | void *adns__alloc_mine(adns_query qu, size_t sz); |
516 | /* Like _interim, but does not record the length for later |
517 | * copying into the answer. This just ensures that the memory |
518 | * will be freed when we're done with the query. |
519 | */ |
520 | |
8e5b0abb |
521 | void *adns__alloc_final(adns_query qu, size_t sz); |
a49a6d7b |
522 | /* Cannot fail, and cannot return 0. |
8e5b0abb |
523 | */ |
37e28fde |
524 | |
68442019 |
525 | void adns__makefinal_block(adns_query qu, void **blpp, size_t sz); |
526 | void adns__makefinal_str(adns_query qu, char **strp); |
527 | |
8b3d55e3 |
528 | void adns__reset_preserved(adns_query qu); |
529 | /* Resets all of the memory management stuff etc. to take account of |
530 | * only the _preserved stuff from _alloc_preserved. Used when we find |
531 | * an error somewhere and want to just report the error (with perhaps |
532 | * CNAME, owner, etc. info), and also when we're halfway through RRs |
533 | * in a datagram and discover that we need to retry the query. |
68442019 |
534 | */ |
e576be50 |
535 | |
3955725c |
536 | void adns__query_done(adns_query qu); |
537 | void adns__query_fail(adns_query qu, adns_status stat); |
f7f83b4a |
538 | |
4353a5c4 |
539 | /* From reply.c: */ |
540 | |
98a3f706 |
541 | void adns__procdgram(adns_state ads, const byte *dgram, int len, |
ebf4877a |
542 | int serv, int viatcp, struct timeval now); |
1f2ababa |
543 | /* This function is allowed to cause new datagrams to be constructed |
544 | * and sent, or even new queries to be started. However, |
545 | * query-sending functions are not allowed to call any general event |
546 | * loop functions in case they accidentally call this. |
f7f83b4a |
547 | * |
548 | * Ie, receiving functions may call sending functions. |
549 | * Sending functions may NOT call receiving functions. |
1f2ababa |
550 | */ |
98a3f706 |
551 | |
552 | /* From types.c: */ |
553 | |
554 | const typeinfo *adns__findtype(adns_rrtype type); |
555 | |
556 | /* From parse.c: */ |
557 | |
f1e474dd |
558 | typedef struct { |
68442019 |
559 | adns_state ads; |
3955725c |
560 | adns_query qu; |
68442019 |
561 | int serv; |
f1e474dd |
562 | const byte *dgram; |
563 | int dglen, max, cbyte, namelen; |
3955725c |
564 | int *dmend_r; |
f1e474dd |
565 | } findlabel_state; |
566 | |
3955725c |
567 | void adns__findlabel_start(findlabel_state *fls, adns_state ads, |
568 | int serv, adns_query qu, |
f1e474dd |
569 | const byte *dgram, int dglen, int max, |
570 | int dmbegin, int *dmend_rlater); |
571 | /* Finds labels in a domain in a datagram. |
572 | * |
573 | * Call this routine first. |
3955725c |
574 | * dmend_rlater may be null. ads (and of course fls) may not be. |
575 | * serv may be -1, qu may be null - they are for error reporting. |
f1e474dd |
576 | */ |
577 | |
609133ee |
578 | adns_status adns__findlabel_next(findlabel_state *fls, |
579 | int *lablen_r, int *labstart_r); |
f1e474dd |
580 | /* Then, call this one repeatedly. |
581 | * |
582 | * It will return adns_s_ok if all is well, and tell you the length |
583 | * and start of successive labels. labstart_r may be null, but |
584 | * lablen_r must not be. |
585 | * |
586 | * After the last label, it will return with *lablen_r zero. |
587 | * Do not then call it again; instead, just throw away the findlabel_state. |
588 | * |
589 | * *dmend_rlater will have been set to point to the next part of |
590 | * the datagram after the label (or after the uncompressed part, |
591 | * if compression was used). *namelen_rlater will have been set |
592 | * to the length of the domain name (total length of labels plus |
593 | * 1 for each intervening dot). |
594 | * |
595 | * If the datagram appears to be truncated, *lablen_r will be -1. |
596 | * *dmend_rlater, *labstart_r and *namelen_r may contain garbage. |
597 | * Do not call _next again. |
598 | * |
599 | * There may also be errors, in which case *dmend_rlater, |
600 | * *namelen_rlater, *lablen_r and *labstart_r may contain garbage. |
601 | * Do not then call findlabel_next again. |
602 | */ |
603 | |
828d89bd |
604 | typedef enum { |
605 | pdf_quoteok= 0x001 |
606 | } parsedomain_flags; |
607 | |
3955725c |
608 | adns_status adns__parse_domain(adns_state ads, int serv, adns_query qu, |
828d89bd |
609 | vbuf *vb, parsedomain_flags flags, |
609133ee |
610 | const byte *dgram, int dglen, int *cbyte_io, |
611 | int max); |
f1e474dd |
612 | /* vb must already have been initialised; it will be reset if necessary. |
613 | * If there is truncation, vb->used will be set to 0; otherwise |
614 | * (if there is no error) vb will be null-terminated. |
615 | * If there is an error vb and *cbyte_io may be left indeterminate. |
3955725c |
616 | * |
617 | * serv may be -1 and qu may be 0 - they are used for error reporting only. |
f1e474dd |
618 | */ |
619 | |
eaa44731 |
620 | adns_status adns__parse_domain_more(findlabel_state *fls, adns_state ads, |
609133ee |
621 | adns_query qu, vbuf *vb, |
622 | parsedomain_flags flags, |
eaa44731 |
623 | const byte *dgram); |
624 | /* Like adns__parse_domain, but you pass it a pre-initialised findlabel_state, |
625 | * for continuing an existing domain or some such of some kind. Also, unlike |
626 | * _parse_domain, the domain data will be appended to vb, rather than replacing |
627 | * the existing contents. |
628 | */ |
629 | |
3955725c |
630 | adns_status adns__findrr(adns_query qu, int serv, |
f1e474dd |
631 | const byte *dgram, int dglen, int *cbyte_io, |
73dba56e |
632 | int *type_r, int *class_r, unsigned long *ttl_r, |
633 | int *rdlen_r, int *rdstart_r, |
3955725c |
634 | int *ownermatchedquery_r); |
c7836bc9 |
635 | /* Finds the extent and some of the contents of an RR in a datagram |
636 | * and does some checks. The datagram is *dgram, length dglen, and |
637 | * the RR starts at *cbyte_io (which is updated afterwards to point |
638 | * to the end of the RR). |
639 | * |
73dba56e |
640 | * The type, class, TTL and RRdata length and start are returned iff |
641 | * the corresponding pointer variables are not null. type_r, class_r |
642 | * and ttl_r may not be null. The TTL will be capped. |
c7836bc9 |
643 | * |
644 | * If ownermatchedquery_r != 0 then the owner domain of this |
645 | * RR will be compared with that in the query (or, if the query |
646 | * has gone to a CNAME lookup, with the canonical name). |
647 | * In this case, *ownermatchedquery_r will be set to 0 or 1. |
648 | * The query datagram (or CNAME datagram) MUST be valid and not truncated. |
649 | * |
650 | * If there is truncation then *type_r will be set to -1 and |
651 | * *cbyte_io, *class_r, *rdlen_r, *rdstart_r and *eo_matched_r will be |
652 | * undefined. |
653 | * |
654 | * qu must obviously be non-null. |
655 | * |
656 | * If an error is returned then *type_r will be undefined too. |
657 | */ |
658 | |
1dfe95d8 |
659 | adns_status adns__findrr_anychk(adns_query qu, int serv, |
660 | const byte *dgram, int dglen, int *cbyte_io, |
609133ee |
661 | int *type_r, int *class_r, |
662 | unsigned long *ttl_r, |
73dba56e |
663 | int *rdlen_r, int *rdstart_r, |
609133ee |
664 | const byte *eo_dgram, int eo_dglen, |
665 | int eo_cbyte, int *eo_matched_r); |
c7836bc9 |
666 | /* Like adns__findrr_checked, except that the datagram and |
667 | * owner to compare with can be specified explicitly. |
668 | * |
669 | * If the caller thinks they know what the owner of the RR ought to |
670 | * be they can pass in details in eo_*: this is another (or perhaps |
671 | * the same datagram), and a pointer to where the putative owner |
672 | * starts in that datagram. In this case *eo_matched_r will be set |
673 | * to 1 if the datagram matched or 0 if it did not. Either |
674 | * both eo_dgram and eo_matched_r must both be non-null, or they |
675 | * must both be null (in which case eo_dglen and eo_cbyte will be ignored). |
676 | * The eo datagram and contained owner domain MUST be valid and |
677 | * untruncated. |
678 | */ |
98a3f706 |
679 | |
609133ee |
680 | void adns__update_expires(adns_query qu, unsigned long ttl, |
681 | struct timeval now); |
73dba56e |
682 | /* Updates the `expires' field in the query, so that it doesn't exceed |
683 | * now + ttl. |
684 | */ |
685 | |
f1e474dd |
686 | int vbuf__append_quoted1035(vbuf *vb, const byte *buf, int len); |
8402e34c |
687 | |
688 | /* From event.c: */ |
4353a5c4 |
689 | |
8402e34c |
690 | void adns__tcp_broken(adns_state ads, const char *what, const char *why); |
f7f83b4a |
691 | /* what and why may be both 0, or both non-0. */ |
692 | |
4353a5c4 |
693 | void adns__tcp_tryconnect(adns_state ads, struct timeval now); |
e576be50 |
694 | |
4353a5c4 |
695 | void adns__autosys(adns_state ads, struct timeval now); |
70ad7a2a |
696 | /* Make all the system calls we want to if the application wants us to. |
697 | * Must not be called from within adns internal processing functions, |
698 | * lest we end up in recursive descent ! |
699 | */ |
37e28fde |
700 | |
620c146d |
701 | void adns__must_gettimeofday(adns_state ads, const struct timeval **now_io, |
702 | struct timeval *tv_buf); |
f7f83b4a |
703 | |
620c146d |
704 | int adns__pollfds(adns_state ads, struct pollfd pollfds_buf[MAX_POLLFDS]); |
705 | void adns__fdevents(adns_state ads, |
706 | const struct pollfd *pollfds, int npollfds, |
707 | int maxfd, const fd_set *readfds, |
708 | const fd_set *writefds, const fd_set *exceptfds, |
709 | struct timeval now, int *r_r); |
940356bd |
710 | int adns__internal_check(adns_state ads, |
711 | adns_query *query_io, |
712 | adns_answer **answer, |
713 | void **context_r); |
620c146d |
714 | |
f7f83b4a |
715 | void adns__timeouts(adns_state ads, int act, |
716 | struct timeval **tv_io, struct timeval *tvbuf, |
717 | struct timeval now); |
718 | /* If act is !0, then this will also deal with the TCP connection |
719 | * if previous events broke it or require it to be connected. |
720 | */ |
721 | |
3e2e5fab |
722 | /* From check.c: */ |
723 | |
28de6442 |
724 | void adns__consistency(adns_state ads, adns_query qu, consistency_checks cc); |
3e2e5fab |
725 | |
37e28fde |
726 | /* Useful static inline functions: */ |
727 | |
609133ee |
728 | static inline int ctype_whitespace(int c) { |
729 | return c==' ' || c=='\n' || c=='\t'; |
730 | } |
37e28fde |
731 | static inline int ctype_digit(int c) { return c>='0' && c<='9'; } |
98a3f706 |
732 | static inline int ctype_alpha(int c) { |
9da4a044 |
733 | return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z'); |
98a3f706 |
734 | } |
609133ee |
735 | static inline int ctype_822special(int c) { |
736 | return strchr("()<>@,;:\\\".[]",c) != 0; |
737 | } |
8af5175d |
738 | static inline int ctype_domainunquoted(int c) { |
739 | return ctype_alpha(c) || ctype_digit(c) || (strchr("-_/+",c) != 0); |
740 | } |
37e28fde |
741 | |
620c146d |
742 | static inline int errno_resources(int e) { return e==ENOMEM || e==ENOBUFS; } |
743 | |
37e28fde |
744 | /* Useful macros */ |
745 | |
609133ee |
746 | #define MEM_ROUND(sz) \ |
747 | (( ((sz)+sizeof(union maxalign)-1) / sizeof(union maxalign) ) \ |
8e5b0abb |
748 | * sizeof(union maxalign) ) |
749 | |
86e7b8d9 |
750 | #define GETIL_B(cb) (((dgram)[(cb)++]) & 0x0ff) |
98a3f706 |
751 | #define GET_B(cb,tv) ((tv)= GETIL_B((cb))) |
609133ee |
752 | #define GET_W(cb,tv) ((tv)=0,(tv)|=(GETIL_B((cb))<<8), (tv)|=GETIL_B(cb), (tv)) |
753 | #define GET_L(cb,tv) ( (tv)=0, \ |
754 | (tv)|=(GETIL_B((cb))<<24), \ |
755 | (tv)|=(GETIL_B((cb))<<16), \ |
756 | (tv)|=(GETIL_B((cb))<<8), \ |
757 | (tv)|=GETIL_B(cb), \ |
73dba56e |
758 | (tv) ) |
98a3f706 |
759 | |
37e28fde |
760 | #endif |