Commit | Line | Data |
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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 | /* | |
ae8cc977 | 8 | * This file is part of adns, which is |
9 | * Copyright (C) 1997-2000,2003,2006 Ian Jackson | |
10 | * Copyright (C) 1999-2000,2003,2006 Tony Finch | |
11 | * Copyright (C) 1991 Massachusetts Institute of Technology | |
12 | * (See the file INSTALL for full details.) | |
f7f83b4a | 13 | * |
e576be50 | 14 | * This program is free software; you can redistribute it and/or modify |
15 | * it under the terms of the GNU General Public License as published by | |
16 | * the Free Software Foundation; either version 2, or (at your option) | |
17 | * any later version. | |
f7f83b4a | 18 | * |
e576be50 | 19 | * This program is distributed in the hope that it will be useful, |
20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
22 | * GNU General Public License for more details. | |
f7f83b4a | 23 | * |
e576be50 | 24 | * You should have received a copy of the GNU General Public License |
25 | * along with this program; if not, write to the Free Software Foundation, | |
f7f83b4a | 26 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
e576be50 | 27 | */ |
37e28fde | 28 | |
29 | #ifndef ADNS_INTERNAL_H_INCLUDED | |
30 | #define ADNS_INTERNAL_H_INCLUDED | |
31 | ||
11b35193 | 32 | #include "config.h" |
4353a5c4 | 33 | typedef unsigned char byte; |
34 | ||
35 | #include <stdarg.h> | |
36 | #include <assert.h> | |
37 | #include <unistd.h> | |
ac868fa8 | 38 | #include <signal.h> |
620c146d | 39 | #include <errno.h> |
b365d68a | 40 | #include <string.h> |
0d66e373 | 41 | #include <stdlib.h> |
4353a5c4 | 42 | |
37e28fde | 43 | #include <sys/time.h> |
44 | ||
45 | #include "adns.h" | |
70ad7a2a | 46 | #include "dlist.h" |
37e28fde | 47 | |
0ebff22d | 48 | #ifdef ADNS_REGRESS_TEST |
49 | # include "hredirect.h" | |
50 | #endif | |
51 | ||
37e28fde | 52 | /* Configuration and constants */ |
53 | ||
54 | #define MAXSERVERS 5 | |
09957b1c | 55 | #define MAXSORTLIST 15 |
4b707d8b | 56 | #define UDPMAXRETRIES 15 |
37e28fde | 57 | #define UDPRETRYMS 2000 |
f7f83b4a | 58 | #define TCPWAITMS 30000 |
59 | #define TCPCONNMS 14000 | |
60 | #define TCPIDLEMS 30000 | |
73dba56e | 61 | #define MAXTTLBELIEVE (7*86400) /* any TTL > 7 days is capped */ |
b9de380c | 62 | |
98a3f706 | 63 | #define DNS_PORT 53 |
b9de380c | 64 | #define DNS_MAXUDP 512 |
5b9dd636 | 65 | #define DNS_MAXLABEL 63 |
b9de380c | 66 | #define DNS_MAXDOMAIN 255 |
67 | #define DNS_HDRSIZE 12 | |
660d7d3b | 68 | #define DNS_IDOFFSET 0 |
b9de380c | 69 | #define DNS_CLASS_IN 1 |
37e28fde | 70 | |
a6536d8b | 71 | #define DNS_INADDR_ARPA "in-addr", "arpa" |
72 | ||
620c146d | 73 | #define MAX_POLLFDS ADNS_POLLFDS_RECOMMENDED |
74 | ||
c5fd1fbb MW |
75 | /* Some preprocessor hackery */ |
76 | ||
77 | #define GLUE(x, y) GLUE_(x, y) | |
78 | #define GLUE_(x, y) x##y | |
79 | ||
80 | /* C99 macro `...' must match at least one argument, so the naive definition | |
81 | * `#define CAR(car, ...) car' won't work. But it's easy to arrange for the | |
82 | * tail to be nonempty if we're just going to discard it anyway. */ | |
83 | #define CAR(...) CAR_(__VA_ARGS__, _) | |
84 | #define CAR_(car, ...) car | |
85 | ||
86 | /* Extracting the tail of an argument list is rather more difficult. The | |
87 | * following trick is based on one by Laurent Deniau to count the number of | |
88 | * arguments to a macro, simplified in two ways: (a) it only handles up to | |
89 | * eight arguments, and (b) it only needs to distinguish the one-argument | |
90 | * case from many arguments. */ | |
91 | #define CDR(...) CDR_(__VA_ARGS__, m, m, m, m, m, m, m, 1, _)(__VA_ARGS__) | |
92 | #define CDR_(_1, _2, _3, _4, _5, _6, _7, _8, n, ...) CDR_##n | |
93 | #define CDR_1(_) | |
94 | #define CDR_m(_, ...) __VA_ARGS__ | |
95 | ||
98a3f706 | 96 | typedef enum { |
3e2e5fab | 97 | cc_user, |
98 | cc_entex, | |
99 | cc_freq | |
100 | } consistency_checks; | |
101 | ||
102 | typedef enum { | |
98a3f706 | 103 | rcode_noerror, |
104 | rcode_formaterror, | |
105 | rcode_servfail, | |
106 | rcode_nxdomain, | |
107 | rcode_notimp, | |
108 | rcode_refused | |
109 | } dns_rcode; | |
110 | ||
37e28fde | 111 | /* Shared data structures */ |
112 | ||
4353a5c4 | 113 | typedef struct { |
114 | int used, avail; | |
115 | byte *buf; | |
116 | } vbuf; | |
117 | ||
0ba0614a | 118 | typedef struct { |
1dfe95d8 | 119 | adns_state ads; |
c7836bc9 | 120 | adns_query qu; |
1dfe95d8 | 121 | int serv; |
c7836bc9 | 122 | const byte *dgram; |
1dfe95d8 | 123 | int dglen, nsstart, nscount, arcount; |
7da21070 | 124 | struct timeval now; |
c7836bc9 | 125 | } parseinfo; |
126 | ||
e1d3be7e MW |
127 | typedef struct { |
128 | void *ext; | |
129 | void (*callback)(adns_query parent, adns_query child); | |
130 | ||
131 | union { | |
132 | adns_rr_addr ptr_addr; | |
133 | } tinfo; /* type-specific state for the query itself: zero-init if you | |
134 | * don't know better. */ | |
135 | ||
136 | union { | |
137 | adns_rr_hostaddr *hostaddr; | |
138 | } pinfo; /* state for use by parent's callback function */ | |
139 | } qcontext; | |
140 | ||
d19b03d0 | 141 | typedef struct typeinfo { |
2c6eb096 | 142 | adns_rrtype typekey; |
86e7b8d9 | 143 | const char *rrtname; |
144 | const char *fmtname; | |
98a3f706 | 145 | int rrsz; |
8e5b0abb | 146 | |
86e7b8d9 | 147 | void (*makefinal)(adns_query qu, void *data); |
148 | /* Change memory management of *data. | |
149 | * Previously, used alloc_interim, now use alloc_final. | |
150 | */ | |
151 | ||
152 | adns_status (*convstring)(vbuf *vb, const void *data); | |
153 | /* Converts the RR data to a string representation in vbuf. | |
154 | * vbuf will be appended to (it must have been initialised), | |
155 | * and will not be null-terminated by convstring. | |
156 | */ | |
157 | ||
609133ee | 158 | adns_status (*parse)(const parseinfo *pai, int cbyte, |
159 | int max, void *store_r); | |
31144a72 | 160 | /* Parse one RR, in dgram of length dglen, starting at cbyte and |
161 | * extending until at most max. | |
162 | * | |
163 | * The RR should be stored at *store_r, of length qu->typei->rrsz. | |
164 | * | |
165 | * If there is an overrun which might indicate truncation, it should set | |
166 | * *rdstart to -1; otherwise it may set it to anything else positive. | |
88372443 | 167 | * |
c7836bc9 | 168 | * nsstart is the offset of the authority section. |
8e5b0abb | 169 | */ |
e062dcae | 170 | |
609133ee | 171 | int (*diff_needswap)(adns_state ads,const void *datap_a,const void *datap_b); |
88372443 | 172 | /* Returns !0 if RR a should be strictly after RR b in the sort order, |
e062dcae | 173 | * 0 otherwise. Must not fail. |
174 | */ | |
d19b03d0 | 175 | |
176 | adns_status (*qdparselabel)(adns_state ads, | |
177 | const char **p_io, const char *pe, int labelnum, | |
178 | char label_r[DNS_MAXDOMAIN], int *ll_io, | |
179 | adns_queryflags flags, | |
180 | const struct typeinfo *typei); | |
181 | /* Parses one label from the query domain string. On entry, *p_io | |
182 | * points to the next character to parse and *ll_io is the size of | |
183 | * the buffer. pe points just after the end of the query domain | |
184 | * string. On successful return, label_r[] and *ll_io are filled in | |
185 | * and *p_io points to *pe or just after the label-ending `.'. */ | |
186 | ||
0e45654b | 187 | void (*postsort)(adns_state ads, void *array, int nrrs, |
d24e2a7e | 188 | const struct typeinfo *typei); |
189 | /* Called immediately after the RRs have been sorted, and may rearrange | |
190 | * them. (This is really for the benefit of SRV's bizarre weighting | |
191 | * stuff.) May be 0 to mean nothing needs to be done. | |
192 | */ | |
0ba0614a | 193 | } typeinfo; |
194 | ||
d19b03d0 | 195 | adns_status adns__qdpl_normal(adns_state ads, |
196 | const char **p_io, const char *pe, int labelnum, | |
197 | char label_r[], int *ll_io, | |
198 | adns_queryflags flags, | |
199 | const typeinfo *typei); | |
200 | /* implemented in transmit.c, used by types.c as default | |
201 | * and as part of implementation for some fancier types */ | |
202 | ||
8e5b0abb | 203 | typedef struct allocnode { |
551ff40f | 204 | struct allocnode *next, *back; |
8e5b0abb | 205 | } allocnode; |
206 | ||
207 | union maxalign { | |
208 | byte d[1]; | |
209 | struct in_addr ia; | |
210 | long l; | |
211 | void *p; | |
212 | void (*fp)(void); | |
213 | union maxalign *up; | |
214 | } data; | |
215 | ||
37e28fde | 216 | struct adns__query { |
3955725c | 217 | adns_state ads; |
f7f83b4a | 218 | enum { query_tosend, query_tcpw, query_childw, query_done } state; |
4353a5c4 | 219 | adns_query back, next, parent; |
37e28fde | 220 | struct { adns_query head, tail; } children; |
221 | struct { adns_query back, next; } siblings; | |
551ff40f | 222 | struct { allocnode *head, *tail; } allocations; |
8b3d55e3 | 223 | int interim_allocd, preserved_allocd; |
68442019 | 224 | void *final_allocspace; |
8ce38e76 | 225 | |
0ba0614a | 226 | const typeinfo *typei; |
e062dcae | 227 | byte *query_dgram; |
8e5b0abb | 228 | int query_dglen; |
f7f83b4a | 229 | |
8e5b0abb | 230 | vbuf vb; |
231 | /* General-purpose messing-about buffer. | |
232 | * Wherever a `big' interface is crossed, this may be corrupted/changed | |
233 | * unless otherwise specified. | |
234 | */ | |
235 | ||
236 | adns_answer *answer; | |
237 | /* This is allocated when a query is submitted, to avoid being unable | |
238 | * to relate errors to queries if we run out of memory. During | |
239 | * query processing status, rrs is 0. cname is set if | |
240 | * we found a cname (this corresponds to cname_dgram in the query | |
241 | * structure). type is set from the word go. nrrs and rrs | |
242 | * are set together, when we find how many rrs there are. | |
22181a31 | 243 | * owner is set during querying unless we're doing searchlist, |
244 | * in which case it is set only when we find an answer. | |
8e5b0abb | 245 | */ |
f7f83b4a | 246 | |
31144a72 | 247 | byte *cname_dgram; |
248 | int cname_dglen, cname_begin; | |
3955725c | 249 | /* If non-0, has been allocated using . */ |
32af6b2a | 250 | |
251 | vbuf search_vb; | |
252 | int search_origlen, search_pos, search_doneabs; | |
253 | /* Used by the searching algorithm. The query domain in textual form | |
254 | * is copied into the vbuf, and _origlen set to its length. Then | |
255 | * we walk the searchlist, if we want to. _pos says where we are | |
256 | * (next entry to try), and _doneabs says whether we've done the | |
660d7d3b | 257 | * absolute query yet (0=not yet, 1=done, -1=must do straight away, |
258 | * but not done yet). If flags doesn't have adns_qf_search then | |
32af6b2a | 259 | * the vbuf is initialised but empty and everything else is zero. |
32af6b2a | 260 | */ |
f7f83b4a | 261 | |
262 | int id, flags, retries; | |
4353a5c4 | 263 | int udpnextserver; |
f7f83b4a | 264 | unsigned long udpsent; /* bitmap indexed by server */ |
37e28fde | 265 | struct timeval timeout; |
73dba56e | 266 | time_t expires; /* Earliest expiry time of any record we used. */ |
a6536d8b | 267 | |
268 | qcontext ctx; | |
ddfda861 | 269 | |
37e28fde | 270 | /* Possible states: |
ddfda861 | 271 | * |
3e2e5fab | 272 | * state Queue child id nextudpserver udpsent tcpfailed |
f7f83b4a | 273 | * |
d8c062fa | 274 | * tosend NONE null >=0 0 zero zero |
f7f83b4a | 275 | * tosend udpw null >=0 any nonzero zero |
d8c062fa | 276 | * tosend NONE null >=0 any nonzero zero |
f7f83b4a | 277 | * |
278 | * tcpw tcpw null >=0 irrelevant any any | |
279 | * | |
8e5b0abb | 280 | * child childw set >=0 irrelevant irrelevant irrelevant |
dcc8e442 | 281 | * child NONE null >=0 irrelevant irrelevant irrelevant |
8e5b0abb | 282 | * done output null -1 irrelevant irrelevant irrelevant |
ddfda861 | 283 | * |
dcc8e442 | 284 | * Queries are only not on a queue when they are actually being processed. |
f7f83b4a | 285 | * Queries in state tcpw/tcpw have been sent (or are in the to-send buffer) |
286 | * iff the tcp connection is in state server_ok. | |
dcc8e442 | 287 | * |
ddfda861 | 288 | * +------------------------+ |
f7f83b4a | 289 | * START -----> | tosend/NONE | |
ddfda861 | 290 | * +------------------------+ |
291 | * / |\ \ | |
292 | * too big for UDP / UDP timeout \ \ send via UDP | |
f7f83b4a | 293 | * send via TCP / more retries \ \ |
294 | * when conn'd / desired \ \ | |
295 | * | | | | |
296 | * v | v | |
297 | * +-----------+ +-------------+ | |
298 | * | tcpw/tcpw | ________ | tosend/udpw | | |
299 | * +-----------+ \ +-------------+ | |
300 | * | | | UDP timeout | | | |
301 | * | | | no more | | | |
302 | * | | | retries | | | |
303 | * \ | TCP died | desired | | | |
304 | * \ \ no more | | | | |
305 | * \ \ servers | TCP / | | |
306 | * \ \ to try | timeout / | | |
307 | * got \ \ v |_ | got | |
ddfda861 | 308 | * reply \ _| +------------------+ / reply |
309 | * \ | done/output FAIL | / | |
310 | * \ +------------------+ / | |
311 | * \ / | |
312 | * _| |_ | |
313 | * (..... got reply ....) | |
314 | * / \ | |
315 | * need child query/ies / \ no child query | |
316 | * / \ | |
317 | * |_ _| | |
f7f83b4a | 318 | * +---------------+ +----------------+ |
319 | * | childw/childw | ----------------> | done/output OK | | |
320 | * +---------------+ children done +----------------+ | |
37e28fde | 321 | */ |
322 | }; | |
323 | ||
f7f83b4a | 324 | struct query_queue { adns_query head, tail; }; |
325 | ||
37e28fde | 326 | struct adns__state { |
37e28fde | 327 | adns_initflags iflags; |
d3a102c4 | 328 | adns_logcallbackfn *logfn; |
329 | void *logfndata; | |
36369543 | 330 | int configerrno; |
f7f83b4a | 331 | struct query_queue udpw, tcpw, childw, output; |
8ce38e76 | 332 | adns_query forallnext; |
4353a5c4 | 333 | int nextid, udpsocket, tcpsocket; |
8e5b0abb | 334 | vbuf tcpsend, tcprecv; |
70ad7a2a | 335 | int nservers, nsortlist, nsearchlist, searchndots, tcpserver, tcprecv_skip; |
f7f83b4a | 336 | enum adns__tcpstate { |
337 | server_disconnected, server_connecting, | |
338 | server_ok, server_broken | |
339 | } tcpstate; | |
37e28fde | 340 | struct timeval tcptimeout; |
4fad263d | 341 | /* This will have tv_sec==0 if it is not valid. It will always be |
342 | * valid if tcpstate _connecting. When _ok, it will be nonzero if | |
343 | * we are idle (ie, tcpw queue is empty), in which case it is the | |
344 | * absolute time when we will close the connection. | |
f7f83b4a | 345 | */ |
ac868fa8 | 346 | struct sigaction stdsigpipe; |
347 | sigset_t stdsigmask; | |
620c146d | 348 | struct pollfd pollfds_buf[MAX_POLLFDS]; |
37e28fde | 349 | struct server { |
350 | struct in_addr addr; | |
351 | } servers[MAXSERVERS]; | |
09957b1c | 352 | struct sortlist { |
353 | struct in_addr base, mask; | |
354 | } sortlist[MAXSORTLIST]; | |
32af6b2a | 355 | char **searchlist; |
0e45654b | 356 | unsigned short rand48xsubi[3]; |
37e28fde | 357 | }; |
358 | ||
359 | /* From setup.c: */ | |
360 | ||
e576be50 | 361 | int adns__setnonblock(adns_state ads, int fd); /* => errno value */ |
362 | ||
363 | /* From general.c: */ | |
364 | ||
d3a102c4 | 365 | void adns__vlprintf(adns_state ads, const char *fmt, va_list al); |
366 | void adns__lprintf(adns_state ads, const char *fmt, | |
367 | ...) PRINTFFORMAT(2,3); | |
368 | ||
4353a5c4 | 369 | void adns__vdiag(adns_state ads, const char *pfx, adns_initflags prevent, |
68442019 | 370 | int serv, adns_query qu, const char *fmt, va_list al); |
31144a72 | 371 | |
372 | void adns__debug(adns_state ads, int serv, adns_query qu, | |
68442019 | 373 | const char *fmt, ...) PRINTFFORMAT(4,5); |
31144a72 | 374 | void adns__warn(adns_state ads, int serv, adns_query qu, |
68442019 | 375 | const char *fmt, ...) PRINTFFORMAT(4,5); |
31144a72 | 376 | void adns__diag(adns_state ads, int serv, adns_query qu, |
68442019 | 377 | const char *fmt, ...) PRINTFFORMAT(4,5); |
37e28fde | 378 | |
4353a5c4 | 379 | int adns__vbuf_ensure(vbuf *vb, int want); |
609133ee | 380 | int adns__vbuf_appendstr(vbuf *vb, const char *data); /* doesn't include nul */ |
4353a5c4 | 381 | int adns__vbuf_append(vbuf *vb, const byte *data, int len); |
ddfda861 | 382 | /* 1=>success, 0=>realloc failed */ |
4353a5c4 | 383 | void adns__vbuf_appendq(vbuf *vb, const byte *data, int len); |
384 | void adns__vbuf_init(vbuf *vb); | |
8e5b0abb | 385 | void adns__vbuf_free(vbuf *vb); |
4353a5c4 | 386 | |
828d89bd | 387 | const char *adns__diag_domain(adns_state ads, int serv, adns_query qu, |
609133ee | 388 | vbuf *vb, |
389 | const byte *dgram, int dglen, int cbyte); | |
e576be50 | 390 | /* Unpicks a domain in a datagram and returns a string suitable for |
391 | * printing it as. Never fails - if an error occurs, it will | |
392 | * return some kind of string describing the error. | |
393 | * | |
3955725c | 394 | * serv may be -1 and qu may be 0. vb must have been initialised, |
e576be50 | 395 | * and will be left in an arbitrary consistent state. |
396 | * | |
397 | * Returns either vb->buf, or a pointer to a string literal. Do not modify | |
398 | * vb before using the return value. | |
399 | */ | |
f7f83b4a | 400 | |
88372443 | 401 | void adns__isort(void *array, int nobjs, int sz, void *tempbuf, |
09957b1c | 402 | int (*needswap)(void *context, const void *a, const void *b), |
403 | void *context); | |
88372443 | 404 | /* Does an insertion sort of array which must contain nobjs objects |
405 | * each sz bytes long. tempbuf must point to a buffer at least | |
406 | * sz bytes long. needswap should return !0 if a>b (strictly, ie | |
407 | * wrong order) 0 if a<=b (ie, order is fine). | |
408 | */ | |
ac868fa8 | 409 | |
410 | void adns__sigpipe_protect(adns_state); | |
411 | void adns__sigpipe_unprotect(adns_state); | |
412 | /* If SIGPIPE protection is not disabled, will block all signals except | |
413 | * SIGPIPE, and set SIGPIPE's disposition to SIG_IGN. (And then restore.) | |
414 | * Each call to _protect must be followed by a call to _unprotect before | |
1f2ababa | 415 | * any significant amount of code gets to run, since the old signal mask |
416 | * is stored in the adns structure. | |
ac868fa8 | 417 | */ |
418 | ||
e576be50 | 419 | /* From transmit.c: */ |
ddfda861 | 420 | |
3955725c | 421 | adns_status adns__mkquery(adns_state ads, vbuf *vb, int *id_r, |
422 | const char *owner, int ol, | |
2c6eb096 | 423 | const typeinfo *typei, adns_rrtype type, |
424 | adns_queryflags flags); | |
660d7d3b | 425 | /* Assembles a query packet in vb. A new id is allocated and returned. |
426 | */ | |
e576be50 | 427 | |
e062dcae | 428 | adns_status adns__mkquery_frdgram(adns_state ads, vbuf *vb, int *id_r, |
609133ee | 429 | const byte *qd_dgram, int qd_dglen, |
430 | int qd_begin, | |
e062dcae | 431 | adns_rrtype type, adns_queryflags flags); |
432 | /* Same as adns__mkquery, but takes the owner domain from an existing datagram. | |
433 | * That domain must be correct and untruncated. | |
434 | */ | |
435 | ||
f7f83b4a | 436 | void adns__querysend_tcp(adns_query qu, struct timeval now); |
437 | /* Query must be in state tcpw/tcpw; it will be sent if possible and | |
438 | * no further processing can be done on it for now. The connection | |
439 | * might be broken, but no reconnect will be attempted. | |
e576be50 | 440 | */ |
441 | ||
d8c062fa | 442 | void adns__query_send(adns_query qu, struct timeval now); |
443 | /* Query must be in state tosend/NONE; it will be moved to a new state, | |
e576be50 | 444 | * and no further processing can be done on it for now. |
609133ee | 445 | * (Resulting state is one of udp/timew, tcpwait/timew (if server not |
446 | * connected), tcpsent/timew, child/childw or done/output.) | |
d8c062fa | 447 | * __query_send may decide to use either UDP or TCP depending whether |
448 | * _qf_usevc is set (or has become set) and whether the query is too | |
449 | * large. | |
e576be50 | 450 | */ |
451 | ||
452 | /* From query.c: */ | |
37e28fde | 453 | |
660d7d3b | 454 | adns_status adns__internal_submit(adns_state ads, adns_query *query_r, |
609133ee | 455 | const typeinfo *typei, vbuf *qumsg_vb, |
456 | int id, | |
660d7d3b | 457 | adns_queryflags flags, struct timeval now, |
458 | const qcontext *ctx); | |
8e5b0abb | 459 | /* Submits a query (for internal use, called during external submits). |
460 | * | |
461 | * The new query is returned in *query_r, or we return adns_s_nomemory. | |
462 | * | |
68442019 | 463 | * The query datagram should already have been assembled in qumsg_vb; |
464 | * the memory for it is _taken over_ by this routine whether it | |
465 | * succeeds or fails (if it succeeds, the vbuf is reused for qu->vb). | |
8e5b0abb | 466 | * |
7da21070 | 467 | * *ctx is copied byte-for-byte into the query. |
dcc8e442 | 468 | * |
469 | * When the child query is done, ctx->callback will be called. The | |
470 | * child will already have been taken off both the global list of | |
471 | * queries in ads and the list of children in the parent. The child | |
472 | * will be freed when the callback returns. The parent will have been | |
4218fb9a | 473 | * taken off the global childw queue. |
474 | * | |
475 | * The callback should either call adns__query_done, if it is | |
476 | * complete, or adns__query_fail, if an error has occurred, in which | |
477 | * case the other children (if any) will be cancelled. If the parent | |
478 | * has more unfinished children (or has just submitted more) then the | |
479 | * callback may choose to wait for them - it must then put the parent | |
480 | * back on the childw queue. | |
8e5b0abb | 481 | */ |
482 | ||
660d7d3b | 483 | void adns__search_next(adns_state ads, adns_query qu, struct timeval now); |
484 | /* Walks down the searchlist for a query with adns_qf_search. | |
485 | * The query should have just had a negative response, or not had | |
486 | * any queries sent yet, and should not be on any queue. | |
487 | * The query_dgram if any will be freed and forgotten and a new | |
488 | * one constructed from the search_* members of the query. | |
489 | * | |
490 | * Cannot fail (in case of error, calls adns__query_fail). | |
491 | */ | |
492 | ||
8e5b0abb | 493 | void *adns__alloc_interim(adns_query qu, size_t sz); |
8b3d55e3 | 494 | void *adns__alloc_preserved(adns_query qu, size_t sz); |
8e5b0abb | 495 | /* Allocates some memory, and records which query it came from |
496 | * and how much there was. | |
497 | * | |
8b3d55e3 | 498 | * If an error occurs in the query, all the memory from _interim is |
499 | * simply freed. If the query succeeds, one large buffer will be made | |
500 | * which is big enough for all these allocations, and then | |
501 | * adns__alloc_final will get memory from this buffer. | |
8e5b0abb | 502 | * |
e062dcae | 503 | * _alloc_interim can fail (and return 0). |
504 | * The caller must ensure that the query is failed. | |
a49a6d7b | 505 | * |
8b3d55e3 | 506 | * The memory from _preserved is is kept and transferred into the |
507 | * larger buffer - unless we run out of memory, in which case it too | |
508 | * is freed. When you use _preserved you have to add code to the | |
509 | * x_nomem error exit case in adns__makefinal_query to clear out the | |
510 | * pointers you made to those allocations, because that's when they're | |
511 | * thrown away; you should also make a note in the declaration of | |
512 | * those pointer variables, to note that they are _preserved rather | |
513 | * than _interim. If they're in the answer, note it here: | |
514 | * answer->cname and answer->owner are _preserved. | |
8e5b0abb | 515 | */ |
516 | ||
609133ee | 517 | void adns__transfer_interim(adns_query from, adns_query to, |
518 | void *block, size_t sz); | |
551ff40f | 519 | /* Transfers an interim allocation from one query to another, so that |
520 | * the `to' query will have room for the data when we get to makefinal | |
521 | * and so that the free will happen when the `to' query is freed | |
522 | * rather than the `from' query. | |
523 | * | |
524 | * It is legal to call adns__transfer_interim with a null pointer; this | |
525 | * has no effect. | |
73dba56e | 526 | * |
527 | * _transfer_interim also ensures that the expiry time of the `to' query | |
528 | * is no later than that of the `from' query, so that child queries' | |
529 | * TTLs get inherited by their parents. | |
551ff40f | 530 | */ |
531 | ||
3955725c | 532 | void *adns__alloc_mine(adns_query qu, size_t sz); |
533 | /* Like _interim, but does not record the length for later | |
534 | * copying into the answer. This just ensures that the memory | |
535 | * will be freed when we're done with the query. | |
536 | */ | |
537 | ||
8e5b0abb | 538 | void *adns__alloc_final(adns_query qu, size_t sz); |
a49a6d7b | 539 | /* Cannot fail, and cannot return 0. |
8e5b0abb | 540 | */ |
37e28fde | 541 | |
68442019 | 542 | void adns__makefinal_block(adns_query qu, void **blpp, size_t sz); |
543 | void adns__makefinal_str(adns_query qu, char **strp); | |
544 | ||
8b3d55e3 | 545 | void adns__reset_preserved(adns_query qu); |
546 | /* Resets all of the memory management stuff etc. to take account of | |
547 | * only the _preserved stuff from _alloc_preserved. Used when we find | |
548 | * an error somewhere and want to just report the error (with perhaps | |
549 | * CNAME, owner, etc. info), and also when we're halfway through RRs | |
550 | * in a datagram and discover that we need to retry the query. | |
68442019 | 551 | */ |
e576be50 | 552 | |
3955725c | 553 | void adns__query_done(adns_query qu); |
554 | void adns__query_fail(adns_query qu, adns_status stat); | |
f7f83b4a | 555 | |
4353a5c4 | 556 | /* From reply.c: */ |
557 | ||
98a3f706 | 558 | void adns__procdgram(adns_state ads, const byte *dgram, int len, |
ebf4877a | 559 | int serv, int viatcp, struct timeval now); |
1f2ababa | 560 | /* This function is allowed to cause new datagrams to be constructed |
561 | * and sent, or even new queries to be started. However, | |
562 | * query-sending functions are not allowed to call any general event | |
563 | * loop functions in case they accidentally call this. | |
f7f83b4a | 564 | * |
565 | * Ie, receiving functions may call sending functions. | |
566 | * Sending functions may NOT call receiving functions. | |
1f2ababa | 567 | */ |
98a3f706 | 568 | |
569 | /* From types.c: */ | |
570 | ||
571 | const typeinfo *adns__findtype(adns_rrtype type); | |
572 | ||
573 | /* From parse.c: */ | |
574 | ||
f1e474dd | 575 | typedef struct { |
68442019 | 576 | adns_state ads; |
3955725c | 577 | adns_query qu; |
68442019 | 578 | int serv; |
f1e474dd | 579 | const byte *dgram; |
580 | int dglen, max, cbyte, namelen; | |
3955725c | 581 | int *dmend_r; |
f1e474dd | 582 | } findlabel_state; |
583 | ||
3955725c | 584 | void adns__findlabel_start(findlabel_state *fls, adns_state ads, |
585 | int serv, adns_query qu, | |
f1e474dd | 586 | const byte *dgram, int dglen, int max, |
587 | int dmbegin, int *dmend_rlater); | |
588 | /* Finds labels in a domain in a datagram. | |
589 | * | |
590 | * Call this routine first. | |
3955725c | 591 | * dmend_rlater may be null. ads (and of course fls) may not be. |
592 | * serv may be -1, qu may be null - they are for error reporting. | |
f1e474dd | 593 | */ |
594 | ||
609133ee | 595 | adns_status adns__findlabel_next(findlabel_state *fls, |
596 | int *lablen_r, int *labstart_r); | |
f1e474dd | 597 | /* Then, call this one repeatedly. |
598 | * | |
599 | * It will return adns_s_ok if all is well, and tell you the length | |
600 | * and start of successive labels. labstart_r may be null, but | |
601 | * lablen_r must not be. | |
602 | * | |
603 | * After the last label, it will return with *lablen_r zero. | |
604 | * Do not then call it again; instead, just throw away the findlabel_state. | |
605 | * | |
606 | * *dmend_rlater will have been set to point to the next part of | |
607 | * the datagram after the label (or after the uncompressed part, | |
608 | * if compression was used). *namelen_rlater will have been set | |
609 | * to the length of the domain name (total length of labels plus | |
610 | * 1 for each intervening dot). | |
611 | * | |
612 | * If the datagram appears to be truncated, *lablen_r will be -1. | |
613 | * *dmend_rlater, *labstart_r and *namelen_r may contain garbage. | |
614 | * Do not call _next again. | |
615 | * | |
616 | * There may also be errors, in which case *dmend_rlater, | |
617 | * *namelen_rlater, *lablen_r and *labstart_r may contain garbage. | |
618 | * Do not then call findlabel_next again. | |
619 | */ | |
620 | ||
828d89bd | 621 | typedef enum { |
622 | pdf_quoteok= 0x001 | |
623 | } parsedomain_flags; | |
624 | ||
3955725c | 625 | adns_status adns__parse_domain(adns_state ads, int serv, adns_query qu, |
828d89bd | 626 | vbuf *vb, parsedomain_flags flags, |
609133ee | 627 | const byte *dgram, int dglen, int *cbyte_io, |
628 | int max); | |
f1e474dd | 629 | /* vb must already have been initialised; it will be reset if necessary. |
630 | * If there is truncation, vb->used will be set to 0; otherwise | |
631 | * (if there is no error) vb will be null-terminated. | |
632 | * If there is an error vb and *cbyte_io may be left indeterminate. | |
3955725c | 633 | * |
634 | * serv may be -1 and qu may be 0 - they are used for error reporting only. | |
f1e474dd | 635 | */ |
636 | ||
eaa44731 | 637 | adns_status adns__parse_domain_more(findlabel_state *fls, adns_state ads, |
609133ee | 638 | adns_query qu, vbuf *vb, |
639 | parsedomain_flags flags, | |
eaa44731 | 640 | const byte *dgram); |
641 | /* Like adns__parse_domain, but you pass it a pre-initialised findlabel_state, | |
642 | * for continuing an existing domain or some such of some kind. Also, unlike | |
643 | * _parse_domain, the domain data will be appended to vb, rather than replacing | |
644 | * the existing contents. | |
645 | */ | |
646 | ||
3955725c | 647 | adns_status adns__findrr(adns_query qu, int serv, |
f1e474dd | 648 | const byte *dgram, int dglen, int *cbyte_io, |
73dba56e | 649 | int *type_r, int *class_r, unsigned long *ttl_r, |
650 | int *rdlen_r, int *rdstart_r, | |
3955725c | 651 | int *ownermatchedquery_r); |
c7836bc9 | 652 | /* Finds the extent and some of the contents of an RR in a datagram |
653 | * and does some checks. The datagram is *dgram, length dglen, and | |
654 | * the RR starts at *cbyte_io (which is updated afterwards to point | |
655 | * to the end of the RR). | |
656 | * | |
73dba56e | 657 | * The type, class, TTL and RRdata length and start are returned iff |
658 | * the corresponding pointer variables are not null. type_r, class_r | |
659 | * and ttl_r may not be null. The TTL will be capped. | |
c7836bc9 | 660 | * |
661 | * If ownermatchedquery_r != 0 then the owner domain of this | |
662 | * RR will be compared with that in the query (or, if the query | |
663 | * has gone to a CNAME lookup, with the canonical name). | |
664 | * In this case, *ownermatchedquery_r will be set to 0 or 1. | |
665 | * The query datagram (or CNAME datagram) MUST be valid and not truncated. | |
666 | * | |
667 | * If there is truncation then *type_r will be set to -1 and | |
668 | * *cbyte_io, *class_r, *rdlen_r, *rdstart_r and *eo_matched_r will be | |
669 | * undefined. | |
670 | * | |
671 | * qu must obviously be non-null. | |
672 | * | |
673 | * If an error is returned then *type_r will be undefined too. | |
674 | */ | |
675 | ||
1dfe95d8 | 676 | adns_status adns__findrr_anychk(adns_query qu, int serv, |
677 | const byte *dgram, int dglen, int *cbyte_io, | |
609133ee | 678 | int *type_r, int *class_r, |
679 | unsigned long *ttl_r, | |
73dba56e | 680 | int *rdlen_r, int *rdstart_r, |
609133ee | 681 | const byte *eo_dgram, int eo_dglen, |
682 | int eo_cbyte, int *eo_matched_r); | |
c7836bc9 | 683 | /* Like adns__findrr_checked, except that the datagram and |
684 | * owner to compare with can be specified explicitly. | |
685 | * | |
686 | * If the caller thinks they know what the owner of the RR ought to | |
687 | * be they can pass in details in eo_*: this is another (or perhaps | |
688 | * the same datagram), and a pointer to where the putative owner | |
689 | * starts in that datagram. In this case *eo_matched_r will be set | |
690 | * to 1 if the datagram matched or 0 if it did not. Either | |
691 | * both eo_dgram and eo_matched_r must both be non-null, or they | |
692 | * must both be null (in which case eo_dglen and eo_cbyte will be ignored). | |
693 | * The eo datagram and contained owner domain MUST be valid and | |
694 | * untruncated. | |
695 | */ | |
98a3f706 | 696 | |
609133ee | 697 | void adns__update_expires(adns_query qu, unsigned long ttl, |
698 | struct timeval now); | |
73dba56e | 699 | /* Updates the `expires' field in the query, so that it doesn't exceed |
700 | * now + ttl. | |
701 | */ | |
702 | ||
f1e474dd | 703 | int vbuf__append_quoted1035(vbuf *vb, const byte *buf, int len); |
8402e34c | 704 | |
705 | /* From event.c: */ | |
4353a5c4 | 706 | |
8402e34c | 707 | void adns__tcp_broken(adns_state ads, const char *what, const char *why); |
f7f83b4a | 708 | /* what and why may be both 0, or both non-0. */ |
709 | ||
4353a5c4 | 710 | void adns__tcp_tryconnect(adns_state ads, struct timeval now); |
e576be50 | 711 | |
4353a5c4 | 712 | void adns__autosys(adns_state ads, struct timeval now); |
70ad7a2a | 713 | /* Make all the system calls we want to if the application wants us to. |
714 | * Must not be called from within adns internal processing functions, | |
715 | * lest we end up in recursive descent ! | |
716 | */ | |
37e28fde | 717 | |
620c146d | 718 | void adns__must_gettimeofday(adns_state ads, const struct timeval **now_io, |
719 | struct timeval *tv_buf); | |
f7f83b4a | 720 | |
620c146d | 721 | int adns__pollfds(adns_state ads, struct pollfd pollfds_buf[MAX_POLLFDS]); |
722 | void adns__fdevents(adns_state ads, | |
723 | const struct pollfd *pollfds, int npollfds, | |
724 | int maxfd, const fd_set *readfds, | |
725 | const fd_set *writefds, const fd_set *exceptfds, | |
726 | struct timeval now, int *r_r); | |
940356bd | 727 | int adns__internal_check(adns_state ads, |
728 | adns_query *query_io, | |
729 | adns_answer **answer, | |
730 | void **context_r); | |
620c146d | 731 | |
f7f83b4a | 732 | void adns__timeouts(adns_state ads, int act, |
733 | struct timeval **tv_io, struct timeval *tvbuf, | |
734 | struct timeval now); | |
735 | /* If act is !0, then this will also deal with the TCP connection | |
736 | * if previous events broke it or require it to be connected. | |
737 | */ | |
738 | ||
3e2e5fab | 739 | /* From check.c: */ |
740 | ||
28de6442 | 741 | void adns__consistency(adns_state ads, adns_query qu, consistency_checks cc); |
3e2e5fab | 742 | |
37e28fde | 743 | /* Useful static inline functions: */ |
744 | ||
609133ee | 745 | static inline int ctype_whitespace(int c) { |
746 | return c==' ' || c=='\n' || c=='\t'; | |
747 | } | |
37e28fde | 748 | static inline int ctype_digit(int c) { return c>='0' && c<='9'; } |
98a3f706 | 749 | static inline int ctype_alpha(int c) { |
9da4a044 | 750 | return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z'); |
98a3f706 | 751 | } |
609133ee | 752 | static inline int ctype_822special(int c) { |
753 | return strchr("()<>@,;:\\\".[]",c) != 0; | |
754 | } | |
8af5175d | 755 | static inline int ctype_domainunquoted(int c) { |
756 | return ctype_alpha(c) || ctype_digit(c) || (strchr("-_/+",c) != 0); | |
757 | } | |
37e28fde | 758 | |
620c146d | 759 | static inline int errno_resources(int e) { return e==ENOMEM || e==ENOBUFS; } |
760 | ||
37e28fde | 761 | /* Useful macros */ |
762 | ||
609133ee | 763 | #define MEM_ROUND(sz) \ |
764 | (( ((sz)+sizeof(union maxalign)-1) / sizeof(union maxalign) ) \ | |
8e5b0abb | 765 | * sizeof(union maxalign) ) |
766 | ||
86e7b8d9 | 767 | #define GETIL_B(cb) (((dgram)[(cb)++]) & 0x0ff) |
98a3f706 | 768 | #define GET_B(cb,tv) ((tv)= GETIL_B((cb))) |
609133ee | 769 | #define GET_W(cb,tv) ((tv)=0,(tv)|=(GETIL_B((cb))<<8), (tv)|=GETIL_B(cb), (tv)) |
770 | #define GET_L(cb,tv) ( (tv)=0, \ | |
771 | (tv)|=(GETIL_B((cb))<<24), \ | |
772 | (tv)|=(GETIL_B((cb))<<16), \ | |
773 | (tv)|=(GETIL_B((cb))<<8), \ | |
774 | (tv)|=GETIL_B(cb), \ | |
73dba56e | 775 | (tv) ) |
98a3f706 | 776 | |
37e28fde | 777 | #endif |