98db6da3 |
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 | /* |
a79ac5ba |
8 | * This file is |
89435c42 |
9 | * Copyright (C) 1997-2000 Ian Jackson <ian@davenant.greenend.org.uk> |
a79ac5ba |
10 | * |
11 | * It is part of adns, which is |
89435c42 |
12 | * Copyright (C) 1997-2000 Ian Jackson <ian@davenant.greenend.org.uk> |
c6826df6 |
13 | * Copyright (C) 1999-2000 Tony Finch <dot@dotat.at> |
d0a057ac |
14 | * |
98db6da3 |
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. |
d0a057ac |
19 | * |
98db6da3 |
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. |
d0a057ac |
24 | * |
98db6da3 |
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, |
d0a057ac |
27 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
98db6da3 |
28 | */ |
dfdbb32c |
29 | |
30 | #ifndef ADNS_INTERNAL_H_INCLUDED |
31 | #define ADNS_INTERNAL_H_INCLUDED |
32 | |
b6953d1b |
33 | #include "config.h" |
d05cc330 |
34 | typedef unsigned char byte; |
35 | |
36 | #include <stdarg.h> |
37 | #include <assert.h> |
38 | #include <unistd.h> |
87e46054 |
39 | #include <signal.h> |
74c94831 |
40 | #include <errno.h> |
0872e289 |
41 | #include <string.h> |
cebf6f2b |
42 | #include <stdlib.h> |
d05cc330 |
43 | |
dfdbb32c |
44 | #include <sys/time.h> |
45 | |
46 | #include "adns.h" |
ab898cf4 |
47 | #include "dlist.h" |
dfdbb32c |
48 | |
09aee00b |
49 | #ifdef ADNS_REGRESS_TEST |
50 | # include "hredirect.h" |
51 | #endif |
52 | |
dfdbb32c |
53 | /* Configuration and constants */ |
54 | |
55 | #define MAXSERVERS 5 |
8c3aa944 |
56 | #define MAXSORTLIST 15 |
59fbb06a |
57 | #define UDPMAXRETRIES 15 |
dfdbb32c |
58 | #define UDPRETRYMS 2000 |
d0a057ac |
59 | #define TCPWAITMS 30000 |
60 | #define TCPCONNMS 14000 |
61 | #define TCPIDLEMS 30000 |
2c7b101b |
62 | #define MAXTTLBELIEVE (7*86400) /* any TTL > 7 days is capped */ |
54ed1d64 |
63 | |
5c596e4d |
64 | #define DNS_PORT 53 |
54ed1d64 |
65 | #define DNS_MAXUDP 512 |
3d75057b |
66 | #define DNS_MAXLABEL 63 |
54ed1d64 |
67 | #define DNS_MAXDOMAIN 255 |
68 | #define DNS_HDRSIZE 12 |
7e6a84a1 |
69 | #define DNS_IDOFFSET 0 |
54ed1d64 |
70 | #define DNS_CLASS_IN 1 |
dfdbb32c |
71 | |
cd1bde2f |
72 | #define DNS_INADDR_ARPA "in-addr", "arpa" |
73 | |
74c94831 |
74 | #define MAX_POLLFDS ADNS_POLLFDS_RECOMMENDED |
75 | |
1389dc72 |
76 | typedef enum { |
77 | cc_user, |
78 | cc_entex, |
79 | cc_freq |
80 | } consistency_checks; |
81 | |
5c596e4d |
82 | typedef enum { |
83 | rcode_noerror, |
84 | rcode_formaterror, |
85 | rcode_servfail, |
86 | rcode_nxdomain, |
87 | rcode_notimp, |
88 | rcode_refused |
89 | } dns_rcode; |
90 | |
dfdbb32c |
91 | /* Shared data structures */ |
92 | |
d05cc330 |
93 | typedef union { |
dfdbb32c |
94 | adns_status status; |
95 | char *cp; |
96 | adns_rrtype type; |
d05cc330 |
97 | int i; |
dfdbb32c |
98 | struct in_addr ia; |
99 | unsigned long ul; |
d05cc330 |
100 | } rr_align; |
101 | |
102 | typedef struct { |
103 | int used, avail; |
104 | byte *buf; |
105 | } vbuf; |
106 | |
a1d2d0ed |
107 | typedef struct { |
26eb6bdc |
108 | adns_state ads; |
a1d2d0ed |
109 | adns_query qu; |
26eb6bdc |
110 | int serv; |
a1d2d0ed |
111 | const byte *dgram; |
26eb6bdc |
112 | int dglen, nsstart, nscount, arcount; |
ba1ddf08 |
113 | struct timeval now; |
a1d2d0ed |
114 | } parseinfo; |
115 | |
bddb4c18 |
116 | typedef struct typeinfo { |
8312a1c2 |
117 | adns_rrtype type; |
1e9efa71 |
118 | const char *rrtname; |
119 | const char *fmtname; |
5c596e4d |
120 | int rrsz; |
965c9782 |
121 | |
1e9efa71 |
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 | |
9c344a42 |
133 | adns_status (*parse)(const parseinfo *pai, int cbyte, |
134 | int max, void *store_r); |
7f702335 |
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. |
f318f883 |
142 | * |
a1d2d0ed |
143 | * nsstart is the offset of the authority section. |
965c9782 |
144 | */ |
f2ad23ee |
145 | |
9c344a42 |
146 | int (*diff_needswap)(adns_state ads,const void *datap_a,const void *datap_b); |
f318f883 |
147 | /* Returns !0 if RR a should be strictly after RR b in the sort order, |
f2ad23ee |
148 | * 0 otherwise. Must not fail. |
149 | */ |
bddb4c18 |
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 | |
8312a1c2 |
162 | } typeinfo; |
163 | |
bddb4c18 |
164 | adns_status adns__qdpl_normal(adns_state ads, |
165 | const char **p_io, const char *pe, int labelnum, |
166 | char label_r[], int *ll_io, |
167 | adns_queryflags flags, |
168 | const typeinfo *typei); |
169 | /* implemented in transmit.c, used by types.c as default |
170 | * and as part of implementation for some fancier types */ |
171 | |
965c9782 |
172 | typedef struct allocnode { |
bc01473e |
173 | struct allocnode *next, *back; |
965c9782 |
174 | } allocnode; |
175 | |
176 | union maxalign { |
177 | byte d[1]; |
178 | struct in_addr ia; |
179 | long l; |
180 | void *p; |
181 | void (*fp)(void); |
182 | union maxalign *up; |
183 | } data; |
184 | |
cd1bde2f |
185 | typedef struct { |
186 | void *ext; |
187 | void (*callback)(adns_query parent, adns_query child); |
188 | union { |
189 | adns_rr_addr ptr_parent_addr; |
190 | adns_rr_hostaddr *hostaddr; |
191 | } info; |
192 | } qcontext; |
193 | |
dfdbb32c |
194 | struct adns__query { |
11c8bf9b |
195 | adns_state ads; |
d0a057ac |
196 | enum { query_tosend, query_tcpw, query_childw, query_done } state; |
d05cc330 |
197 | adns_query back, next, parent; |
dfdbb32c |
198 | struct { adns_query head, tail; } children; |
199 | struct { adns_query back, next; } siblings; |
bc01473e |
200 | struct { allocnode *head, *tail; } allocations; |
1be24aef |
201 | int interim_allocd, preserved_allocd; |
ae41e040 |
202 | void *final_allocspace; |
8f2aa812 |
203 | |
8312a1c2 |
204 | const typeinfo *typei; |
f2ad23ee |
205 | byte *query_dgram; |
965c9782 |
206 | int query_dglen; |
d0a057ac |
207 | |
965c9782 |
208 | vbuf vb; |
209 | /* General-purpose messing-about buffer. |
210 | * Wherever a `big' interface is crossed, this may be corrupted/changed |
211 | * unless otherwise specified. |
212 | */ |
213 | |
214 | adns_answer *answer; |
215 | /* This is allocated when a query is submitted, to avoid being unable |
216 | * to relate errors to queries if we run out of memory. During |
217 | * query processing status, rrs is 0. cname is set if |
218 | * we found a cname (this corresponds to cname_dgram in the query |
219 | * structure). type is set from the word go. nrrs and rrs |
220 | * are set together, when we find how many rrs there are. |
b2988d3e |
221 | * owner is set during querying unless we're doing searchlist, |
222 | * in which case it is set only when we find an answer. |
965c9782 |
223 | */ |
d0a057ac |
224 | |
7f702335 |
225 | byte *cname_dgram; |
226 | int cname_dglen, cname_begin; |
11c8bf9b |
227 | /* If non-0, has been allocated using . */ |
11f553d9 |
228 | |
229 | vbuf search_vb; |
230 | int search_origlen, search_pos, search_doneabs; |
231 | /* Used by the searching algorithm. The query domain in textual form |
232 | * is copied into the vbuf, and _origlen set to its length. Then |
233 | * we walk the searchlist, if we want to. _pos says where we are |
234 | * (next entry to try), and _doneabs says whether we've done the |
7e6a84a1 |
235 | * absolute query yet (0=not yet, 1=done, -1=must do straight away, |
236 | * but not done yet). If flags doesn't have adns_qf_search then |
11f553d9 |
237 | * the vbuf is initialised but empty and everything else is zero. |
11f553d9 |
238 | */ |
d0a057ac |
239 | |
240 | int id, flags, retries; |
d05cc330 |
241 | int udpnextserver; |
d0a057ac |
242 | unsigned long udpsent; /* bitmap indexed by server */ |
dfdbb32c |
243 | struct timeval timeout; |
2c7b101b |
244 | time_t expires; /* Earliest expiry time of any record we used. */ |
cd1bde2f |
245 | |
246 | qcontext ctx; |
96e79df5 |
247 | |
dfdbb32c |
248 | /* Possible states: |
96e79df5 |
249 | * |
1389dc72 |
250 | * state Queue child id nextudpserver udpsent tcpfailed |
d0a057ac |
251 | * |
24d52b13 |
252 | * tosend NONE null >=0 0 zero zero |
d0a057ac |
253 | * tosend udpw null >=0 any nonzero zero |
24d52b13 |
254 | * tosend NONE null >=0 any nonzero zero |
d0a057ac |
255 | * |
256 | * tcpw tcpw null >=0 irrelevant any any |
257 | * |
965c9782 |
258 | * child childw set >=0 irrelevant irrelevant irrelevant |
d861b9b7 |
259 | * child NONE null >=0 irrelevant irrelevant irrelevant |
965c9782 |
260 | * done output null -1 irrelevant irrelevant irrelevant |
96e79df5 |
261 | * |
d861b9b7 |
262 | * Queries are only not on a queue when they are actually being processed. |
d0a057ac |
263 | * Queries in state tcpw/tcpw have been sent (or are in the to-send buffer) |
264 | * iff the tcp connection is in state server_ok. |
d861b9b7 |
265 | * |
96e79df5 |
266 | * +------------------------+ |
d0a057ac |
267 | * START -----> | tosend/NONE | |
96e79df5 |
268 | * +------------------------+ |
269 | * / |\ \ |
270 | * too big for UDP / UDP timeout \ \ send via UDP |
d0a057ac |
271 | * send via TCP / more retries \ \ |
272 | * when conn'd / desired \ \ |
273 | * | | | |
274 | * v | v |
275 | * +-----------+ +-------------+ |
276 | * | tcpw/tcpw | ________ | tosend/udpw | |
277 | * +-----------+ \ +-------------+ |
278 | * | | | UDP timeout | | |
279 | * | | | no more | | |
280 | * | | | retries | | |
281 | * \ | TCP died | desired | | |
282 | * \ \ no more | | | |
283 | * \ \ servers | TCP / | |
284 | * \ \ to try | timeout / | |
285 | * got \ \ v |_ | got |
96e79df5 |
286 | * reply \ _| +------------------+ / reply |
287 | * \ | done/output FAIL | / |
288 | * \ +------------------+ / |
289 | * \ / |
290 | * _| |_ |
291 | * (..... got reply ....) |
292 | * / \ |
293 | * need child query/ies / \ no child query |
294 | * / \ |
295 | * |_ _| |
d0a057ac |
296 | * +---------------+ +----------------+ |
297 | * | childw/childw | ----------------> | done/output OK | |
298 | * +---------------+ children done +----------------+ |
dfdbb32c |
299 | */ |
300 | }; |
301 | |
d0a057ac |
302 | struct query_queue { adns_query head, tail; }; |
303 | |
dfdbb32c |
304 | struct adns__state { |
dfdbb32c |
305 | adns_initflags iflags; |
86ea5e62 |
306 | adns_logcallbackfn *logfn; |
307 | void *logfndata; |
d6b271ae |
308 | int configerrno; |
d0a057ac |
309 | struct query_queue udpw, tcpw, childw, output; |
8f2aa812 |
310 | adns_query forallnext; |
d05cc330 |
311 | int nextid, udpsocket, tcpsocket; |
965c9782 |
312 | vbuf tcpsend, tcprecv; |
ab898cf4 |
313 | int nservers, nsortlist, nsearchlist, searchndots, tcpserver, tcprecv_skip; |
d0a057ac |
314 | enum adns__tcpstate { |
315 | server_disconnected, server_connecting, |
316 | server_ok, server_broken |
317 | } tcpstate; |
dfdbb32c |
318 | struct timeval tcptimeout; |
8744cce8 |
319 | /* This will have tv_sec==0 if it is not valid. It will always be |
320 | * valid if tcpstate _connecting. When _ok, it will be nonzero if |
321 | * we are idle (ie, tcpw queue is empty), in which case it is the |
322 | * absolute time when we will close the connection. |
d0a057ac |
323 | */ |
87e46054 |
324 | struct sigaction stdsigpipe; |
325 | sigset_t stdsigmask; |
74c94831 |
326 | struct pollfd pollfds_buf[MAX_POLLFDS]; |
dfdbb32c |
327 | struct server { |
328 | struct in_addr addr; |
329 | } servers[MAXSERVERS]; |
8c3aa944 |
330 | struct sortlist { |
331 | struct in_addr base, mask; |
332 | } sortlist[MAXSORTLIST]; |
11f553d9 |
333 | char **searchlist; |
dfdbb32c |
334 | }; |
335 | |
336 | /* From setup.c: */ |
337 | |
98db6da3 |
338 | int adns__setnonblock(adns_state ads, int fd); /* => errno value */ |
339 | |
340 | /* From general.c: */ |
341 | |
86ea5e62 |
342 | void adns__vlprintf(adns_state ads, const char *fmt, va_list al); |
343 | void adns__lprintf(adns_state ads, const char *fmt, |
344 | ...) PRINTFFORMAT(2,3); |
345 | |
d05cc330 |
346 | void adns__vdiag(adns_state ads, const char *pfx, adns_initflags prevent, |
ae41e040 |
347 | int serv, adns_query qu, const char *fmt, va_list al); |
7f702335 |
348 | |
349 | void adns__debug(adns_state ads, int serv, adns_query qu, |
ae41e040 |
350 | const char *fmt, ...) PRINTFFORMAT(4,5); |
7f702335 |
351 | void adns__warn(adns_state ads, int serv, adns_query qu, |
ae41e040 |
352 | const char *fmt, ...) PRINTFFORMAT(4,5); |
7f702335 |
353 | void adns__diag(adns_state ads, int serv, adns_query qu, |
ae41e040 |
354 | const char *fmt, ...) PRINTFFORMAT(4,5); |
dfdbb32c |
355 | |
d05cc330 |
356 | int adns__vbuf_ensure(vbuf *vb, int want); |
9c344a42 |
357 | int adns__vbuf_appendstr(vbuf *vb, const char *data); /* doesn't include nul */ |
d05cc330 |
358 | int adns__vbuf_append(vbuf *vb, const byte *data, int len); |
96e79df5 |
359 | /* 1=>success, 0=>realloc failed */ |
d05cc330 |
360 | void adns__vbuf_appendq(vbuf *vb, const byte *data, int len); |
361 | void adns__vbuf_init(vbuf *vb); |
965c9782 |
362 | void adns__vbuf_free(vbuf *vb); |
d05cc330 |
363 | |
cd363ffd |
364 | const char *adns__diag_domain(adns_state ads, int serv, adns_query qu, |
9c344a42 |
365 | vbuf *vb, |
366 | const byte *dgram, int dglen, int cbyte); |
98db6da3 |
367 | /* Unpicks a domain in a datagram and returns a string suitable for |
368 | * printing it as. Never fails - if an error occurs, it will |
369 | * return some kind of string describing the error. |
370 | * |
11c8bf9b |
371 | * serv may be -1 and qu may be 0. vb must have been initialised, |
98db6da3 |
372 | * and will be left in an arbitrary consistent state. |
373 | * |
374 | * Returns either vb->buf, or a pointer to a string literal. Do not modify |
375 | * vb before using the return value. |
376 | */ |
d0a057ac |
377 | |
f318f883 |
378 | void adns__isort(void *array, int nobjs, int sz, void *tempbuf, |
8c3aa944 |
379 | int (*needswap)(void *context, const void *a, const void *b), |
380 | void *context); |
f318f883 |
381 | /* Does an insertion sort of array which must contain nobjs objects |
382 | * each sz bytes long. tempbuf must point to a buffer at least |
383 | * sz bytes long. needswap should return !0 if a>b (strictly, ie |
384 | * wrong order) 0 if a<=b (ie, order is fine). |
385 | */ |
87e46054 |
386 | |
387 | void adns__sigpipe_protect(adns_state); |
388 | void adns__sigpipe_unprotect(adns_state); |
389 | /* If SIGPIPE protection is not disabled, will block all signals except |
390 | * SIGPIPE, and set SIGPIPE's disposition to SIG_IGN. (And then restore.) |
391 | * Each call to _protect must be followed by a call to _unprotect before |
a225dda5 |
392 | * any significant amount of code gets to run, since the old signal mask |
393 | * is stored in the adns structure. |
87e46054 |
394 | */ |
395 | |
98db6da3 |
396 | /* From transmit.c: */ |
96e79df5 |
397 | |
11c8bf9b |
398 | adns_status adns__mkquery(adns_state ads, vbuf *vb, int *id_r, |
399 | const char *owner, int ol, |
98db6da3 |
400 | const typeinfo *typei, adns_queryflags flags); |
7e6a84a1 |
401 | /* Assembles a query packet in vb. A new id is allocated and returned. |
402 | */ |
98db6da3 |
403 | |
f2ad23ee |
404 | adns_status adns__mkquery_frdgram(adns_state ads, vbuf *vb, int *id_r, |
9c344a42 |
405 | const byte *qd_dgram, int qd_dglen, |
406 | int qd_begin, |
f2ad23ee |
407 | adns_rrtype type, adns_queryflags flags); |
408 | /* Same as adns__mkquery, but takes the owner domain from an existing datagram. |
409 | * That domain must be correct and untruncated. |
410 | */ |
411 | |
d0a057ac |
412 | void adns__querysend_tcp(adns_query qu, struct timeval now); |
413 | /* Query must be in state tcpw/tcpw; it will be sent if possible and |
414 | * no further processing can be done on it for now. The connection |
415 | * might be broken, but no reconnect will be attempted. |
98db6da3 |
416 | */ |
417 | |
24d52b13 |
418 | void adns__query_send(adns_query qu, struct timeval now); |
419 | /* Query must be in state tosend/NONE; it will be moved to a new state, |
98db6da3 |
420 | * and no further processing can be done on it for now. |
9c344a42 |
421 | * (Resulting state is one of udp/timew, tcpwait/timew (if server not |
422 | * connected), tcpsent/timew, child/childw or done/output.) |
24d52b13 |
423 | * __query_send may decide to use either UDP or TCP depending whether |
424 | * _qf_usevc is set (or has become set) and whether the query is too |
425 | * large. |
98db6da3 |
426 | */ |
427 | |
428 | /* From query.c: */ |
dfdbb32c |
429 | |
7e6a84a1 |
430 | adns_status adns__internal_submit(adns_state ads, adns_query *query_r, |
9c344a42 |
431 | const typeinfo *typei, vbuf *qumsg_vb, |
432 | int id, |
7e6a84a1 |
433 | adns_queryflags flags, struct timeval now, |
434 | const qcontext *ctx); |
965c9782 |
435 | /* Submits a query (for internal use, called during external submits). |
436 | * |
437 | * The new query is returned in *query_r, or we return adns_s_nomemory. |
438 | * |
ae41e040 |
439 | * The query datagram should already have been assembled in qumsg_vb; |
440 | * the memory for it is _taken over_ by this routine whether it |
441 | * succeeds or fails (if it succeeds, the vbuf is reused for qu->vb). |
965c9782 |
442 | * |
ba1ddf08 |
443 | * *ctx is copied byte-for-byte into the query. |
d861b9b7 |
444 | * |
445 | * When the child query is done, ctx->callback will be called. The |
446 | * child will already have been taken off both the global list of |
447 | * queries in ads and the list of children in the parent. The child |
448 | * will be freed when the callback returns. The parent will have been |
cb32030b |
449 | * taken off the global childw queue. |
450 | * |
451 | * The callback should either call adns__query_done, if it is |
452 | * complete, or adns__query_fail, if an error has occurred, in which |
453 | * case the other children (if any) will be cancelled. If the parent |
454 | * has more unfinished children (or has just submitted more) then the |
455 | * callback may choose to wait for them - it must then put the parent |
456 | * back on the childw queue. |
965c9782 |
457 | */ |
458 | |
7e6a84a1 |
459 | void adns__search_next(adns_state ads, adns_query qu, struct timeval now); |
460 | /* Walks down the searchlist for a query with adns_qf_search. |
461 | * The query should have just had a negative response, or not had |
462 | * any queries sent yet, and should not be on any queue. |
463 | * The query_dgram if any will be freed and forgotten and a new |
464 | * one constructed from the search_* members of the query. |
465 | * |
466 | * Cannot fail (in case of error, calls adns__query_fail). |
467 | */ |
468 | |
965c9782 |
469 | void *adns__alloc_interim(adns_query qu, size_t sz); |
1be24aef |
470 | void *adns__alloc_preserved(adns_query qu, size_t sz); |
965c9782 |
471 | /* Allocates some memory, and records which query it came from |
472 | * and how much there was. |
473 | * |
1be24aef |
474 | * If an error occurs in the query, all the memory from _interim is |
475 | * simply freed. If the query succeeds, one large buffer will be made |
476 | * which is big enough for all these allocations, and then |
477 | * adns__alloc_final will get memory from this buffer. |
965c9782 |
478 | * |
f2ad23ee |
479 | * _alloc_interim can fail (and return 0). |
480 | * The caller must ensure that the query is failed. |
f47cdeec |
481 | * |
1be24aef |
482 | * The memory from _preserved is is kept and transferred into the |
483 | * larger buffer - unless we run out of memory, in which case it too |
484 | * is freed. When you use _preserved you have to add code to the |
485 | * x_nomem error exit case in adns__makefinal_query to clear out the |
486 | * pointers you made to those allocations, because that's when they're |
487 | * thrown away; you should also make a note in the declaration of |
488 | * those pointer variables, to note that they are _preserved rather |
489 | * than _interim. If they're in the answer, note it here: |
490 | * answer->cname and answer->owner are _preserved. |
965c9782 |
491 | */ |
492 | |
9c344a42 |
493 | void adns__transfer_interim(adns_query from, adns_query to, |
494 | void *block, size_t sz); |
bc01473e |
495 | /* Transfers an interim allocation from one query to another, so that |
496 | * the `to' query will have room for the data when we get to makefinal |
497 | * and so that the free will happen when the `to' query is freed |
498 | * rather than the `from' query. |
499 | * |
500 | * It is legal to call adns__transfer_interim with a null pointer; this |
501 | * has no effect. |
2c7b101b |
502 | * |
503 | * _transfer_interim also ensures that the expiry time of the `to' query |
504 | * is no later than that of the `from' query, so that child queries' |
505 | * TTLs get inherited by their parents. |
bc01473e |
506 | */ |
507 | |
11c8bf9b |
508 | void *adns__alloc_mine(adns_query qu, size_t sz); |
509 | /* Like _interim, but does not record the length for later |
510 | * copying into the answer. This just ensures that the memory |
511 | * will be freed when we're done with the query. |
512 | */ |
513 | |
965c9782 |
514 | void *adns__alloc_final(adns_query qu, size_t sz); |
f47cdeec |
515 | /* Cannot fail, and cannot return 0. |
965c9782 |
516 | */ |
dfdbb32c |
517 | |
ae41e040 |
518 | void adns__makefinal_block(adns_query qu, void **blpp, size_t sz); |
519 | void adns__makefinal_str(adns_query qu, char **strp); |
520 | |
1be24aef |
521 | void adns__reset_preserved(adns_query qu); |
522 | /* Resets all of the memory management stuff etc. to take account of |
523 | * only the _preserved stuff from _alloc_preserved. Used when we find |
524 | * an error somewhere and want to just report the error (with perhaps |
525 | * CNAME, owner, etc. info), and also when we're halfway through RRs |
526 | * in a datagram and discover that we need to retry the query. |
ae41e040 |
527 | */ |
98db6da3 |
528 | |
11c8bf9b |
529 | void adns__query_done(adns_query qu); |
530 | void adns__query_fail(adns_query qu, adns_status stat); |
d0a057ac |
531 | |
d05cc330 |
532 | /* From reply.c: */ |
533 | |
5c596e4d |
534 | void adns__procdgram(adns_state ads, const byte *dgram, int len, |
c84b7355 |
535 | int serv, int viatcp, struct timeval now); |
a225dda5 |
536 | /* This function is allowed to cause new datagrams to be constructed |
537 | * and sent, or even new queries to be started. However, |
538 | * query-sending functions are not allowed to call any general event |
539 | * loop functions in case they accidentally call this. |
d0a057ac |
540 | * |
541 | * Ie, receiving functions may call sending functions. |
542 | * Sending functions may NOT call receiving functions. |
a225dda5 |
543 | */ |
5c596e4d |
544 | |
545 | /* From types.c: */ |
546 | |
547 | const typeinfo *adns__findtype(adns_rrtype type); |
548 | |
549 | /* From parse.c: */ |
550 | |
403fa0e0 |
551 | typedef struct { |
ae41e040 |
552 | adns_state ads; |
11c8bf9b |
553 | adns_query qu; |
ae41e040 |
554 | int serv; |
403fa0e0 |
555 | const byte *dgram; |
556 | int dglen, max, cbyte, namelen; |
11c8bf9b |
557 | int *dmend_r; |
403fa0e0 |
558 | } findlabel_state; |
559 | |
11c8bf9b |
560 | void adns__findlabel_start(findlabel_state *fls, adns_state ads, |
561 | int serv, adns_query qu, |
403fa0e0 |
562 | const byte *dgram, int dglen, int max, |
563 | int dmbegin, int *dmend_rlater); |
564 | /* Finds labels in a domain in a datagram. |
565 | * |
566 | * Call this routine first. |
11c8bf9b |
567 | * dmend_rlater may be null. ads (and of course fls) may not be. |
568 | * serv may be -1, qu may be null - they are for error reporting. |
403fa0e0 |
569 | */ |
570 | |
9c344a42 |
571 | adns_status adns__findlabel_next(findlabel_state *fls, |
572 | int *lablen_r, int *labstart_r); |
403fa0e0 |
573 | /* Then, call this one repeatedly. |
574 | * |
575 | * It will return adns_s_ok if all is well, and tell you the length |
576 | * and start of successive labels. labstart_r may be null, but |
577 | * lablen_r must not be. |
578 | * |
579 | * After the last label, it will return with *lablen_r zero. |
580 | * Do not then call it again; instead, just throw away the findlabel_state. |
581 | * |
582 | * *dmend_rlater will have been set to point to the next part of |
583 | * the datagram after the label (or after the uncompressed part, |
584 | * if compression was used). *namelen_rlater will have been set |
585 | * to the length of the domain name (total length of labels plus |
586 | * 1 for each intervening dot). |
587 | * |
588 | * If the datagram appears to be truncated, *lablen_r will be -1. |
589 | * *dmend_rlater, *labstart_r and *namelen_r may contain garbage. |
590 | * Do not call _next again. |
591 | * |
592 | * There may also be errors, in which case *dmend_rlater, |
593 | * *namelen_rlater, *lablen_r and *labstart_r may contain garbage. |
594 | * Do not then call findlabel_next again. |
595 | */ |
596 | |
cd363ffd |
597 | typedef enum { |
598 | pdf_quoteok= 0x001 |
599 | } parsedomain_flags; |
600 | |
11c8bf9b |
601 | adns_status adns__parse_domain(adns_state ads, int serv, adns_query qu, |
cd363ffd |
602 | vbuf *vb, parsedomain_flags flags, |
9c344a42 |
603 | const byte *dgram, int dglen, int *cbyte_io, |
604 | int max); |
403fa0e0 |
605 | /* vb must already have been initialised; it will be reset if necessary. |
606 | * If there is truncation, vb->used will be set to 0; otherwise |
607 | * (if there is no error) vb will be null-terminated. |
608 | * If there is an error vb and *cbyte_io may be left indeterminate. |
11c8bf9b |
609 | * |
610 | * serv may be -1 and qu may be 0 - they are used for error reporting only. |
403fa0e0 |
611 | */ |
612 | |
6f2c243f |
613 | adns_status adns__parse_domain_more(findlabel_state *fls, adns_state ads, |
9c344a42 |
614 | adns_query qu, vbuf *vb, |
615 | parsedomain_flags flags, |
6f2c243f |
616 | const byte *dgram); |
617 | /* Like adns__parse_domain, but you pass it a pre-initialised findlabel_state, |
618 | * for continuing an existing domain or some such of some kind. Also, unlike |
619 | * _parse_domain, the domain data will be appended to vb, rather than replacing |
620 | * the existing contents. |
621 | */ |
622 | |
11c8bf9b |
623 | adns_status adns__findrr(adns_query qu, int serv, |
403fa0e0 |
624 | const byte *dgram, int dglen, int *cbyte_io, |
2c7b101b |
625 | int *type_r, int *class_r, unsigned long *ttl_r, |
626 | int *rdlen_r, int *rdstart_r, |
11c8bf9b |
627 | int *ownermatchedquery_r); |
a1d2d0ed |
628 | /* Finds the extent and some of the contents of an RR in a datagram |
629 | * and does some checks. The datagram is *dgram, length dglen, and |
630 | * the RR starts at *cbyte_io (which is updated afterwards to point |
631 | * to the end of the RR). |
632 | * |
2c7b101b |
633 | * The type, class, TTL and RRdata length and start are returned iff |
634 | * the corresponding pointer variables are not null. type_r, class_r |
635 | * and ttl_r may not be null. The TTL will be capped. |
a1d2d0ed |
636 | * |
637 | * If ownermatchedquery_r != 0 then the owner domain of this |
638 | * RR will be compared with that in the query (or, if the query |
639 | * has gone to a CNAME lookup, with the canonical name). |
640 | * In this case, *ownermatchedquery_r will be set to 0 or 1. |
641 | * The query datagram (or CNAME datagram) MUST be valid and not truncated. |
642 | * |
643 | * If there is truncation then *type_r will be set to -1 and |
644 | * *cbyte_io, *class_r, *rdlen_r, *rdstart_r and *eo_matched_r will be |
645 | * undefined. |
646 | * |
647 | * qu must obviously be non-null. |
648 | * |
649 | * If an error is returned then *type_r will be undefined too. |
650 | */ |
651 | |
26eb6bdc |
652 | adns_status adns__findrr_anychk(adns_query qu, int serv, |
653 | const byte *dgram, int dglen, int *cbyte_io, |
9c344a42 |
654 | int *type_r, int *class_r, |
655 | unsigned long *ttl_r, |
2c7b101b |
656 | int *rdlen_r, int *rdstart_r, |
9c344a42 |
657 | const byte *eo_dgram, int eo_dglen, |
658 | int eo_cbyte, int *eo_matched_r); |
a1d2d0ed |
659 | /* Like adns__findrr_checked, except that the datagram and |
660 | * owner to compare with can be specified explicitly. |
661 | * |
662 | * If the caller thinks they know what the owner of the RR ought to |
663 | * be they can pass in details in eo_*: this is another (or perhaps |
664 | * the same datagram), and a pointer to where the putative owner |
665 | * starts in that datagram. In this case *eo_matched_r will be set |
666 | * to 1 if the datagram matched or 0 if it did not. Either |
667 | * both eo_dgram and eo_matched_r must both be non-null, or they |
668 | * must both be null (in which case eo_dglen and eo_cbyte will be ignored). |
669 | * The eo datagram and contained owner domain MUST be valid and |
670 | * untruncated. |
671 | */ |
5c596e4d |
672 | |
9c344a42 |
673 | void adns__update_expires(adns_query qu, unsigned long ttl, |
674 | struct timeval now); |
2c7b101b |
675 | /* Updates the `expires' field in the query, so that it doesn't exceed |
676 | * now + ttl. |
677 | */ |
678 | |
403fa0e0 |
679 | int vbuf__append_quoted1035(vbuf *vb, const byte *buf, int len); |
71324651 |
680 | |
681 | /* From event.c: */ |
d05cc330 |
682 | |
71324651 |
683 | void adns__tcp_broken(adns_state ads, const char *what, const char *why); |
d0a057ac |
684 | /* what and why may be both 0, or both non-0. */ |
685 | |
d05cc330 |
686 | void adns__tcp_tryconnect(adns_state ads, struct timeval now); |
98db6da3 |
687 | |
d05cc330 |
688 | void adns__autosys(adns_state ads, struct timeval now); |
ab898cf4 |
689 | /* Make all the system calls we want to if the application wants us to. |
690 | * Must not be called from within adns internal processing functions, |
691 | * lest we end up in recursive descent ! |
692 | */ |
dfdbb32c |
693 | |
74c94831 |
694 | void adns__must_gettimeofday(adns_state ads, const struct timeval **now_io, |
695 | struct timeval *tv_buf); |
d0a057ac |
696 | |
74c94831 |
697 | int adns__pollfds(adns_state ads, struct pollfd pollfds_buf[MAX_POLLFDS]); |
698 | void adns__fdevents(adns_state ads, |
699 | const struct pollfd *pollfds, int npollfds, |
700 | int maxfd, const fd_set *readfds, |
701 | const fd_set *writefds, const fd_set *exceptfds, |
702 | struct timeval now, int *r_r); |
ef20fccf |
703 | int adns__internal_check(adns_state ads, |
704 | adns_query *query_io, |
705 | adns_answer **answer, |
706 | void **context_r); |
74c94831 |
707 | |
d0a057ac |
708 | void adns__timeouts(adns_state ads, int act, |
709 | struct timeval **tv_io, struct timeval *tvbuf, |
710 | struct timeval now); |
711 | /* If act is !0, then this will also deal with the TCP connection |
712 | * if previous events broke it or require it to be connected. |
713 | */ |
714 | |
1389dc72 |
715 | /* From check.c: */ |
716 | |
2ac463bf |
717 | void adns__consistency(adns_state ads, adns_query qu, consistency_checks cc); |
1389dc72 |
718 | |
dfdbb32c |
719 | /* Useful static inline functions: */ |
720 | |
9c344a42 |
721 | static inline int ctype_whitespace(int c) { |
722 | return c==' ' || c=='\n' || c=='\t'; |
723 | } |
dfdbb32c |
724 | static inline int ctype_digit(int c) { return c>='0' && c<='9'; } |
5c596e4d |
725 | static inline int ctype_alpha(int c) { |
c2875680 |
726 | return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z'); |
5c596e4d |
727 | } |
9c344a42 |
728 | static inline int ctype_822special(int c) { |
729 | return strchr("()<>@,;:\\\".[]",c) != 0; |
730 | } |
996e3b68 |
731 | static inline int ctype_domainunquoted(int c) { |
732 | return ctype_alpha(c) || ctype_digit(c) || (strchr("-_/+",c) != 0); |
733 | } |
dfdbb32c |
734 | |
74c94831 |
735 | static inline int errno_resources(int e) { return e==ENOMEM || e==ENOBUFS; } |
736 | |
dfdbb32c |
737 | /* Useful macros */ |
738 | |
9c344a42 |
739 | #define MEM_ROUND(sz) \ |
740 | (( ((sz)+sizeof(union maxalign)-1) / sizeof(union maxalign) ) \ |
965c9782 |
741 | * sizeof(union maxalign) ) |
742 | |
1e9efa71 |
743 | #define GETIL_B(cb) (((dgram)[(cb)++]) & 0x0ff) |
5c596e4d |
744 | #define GET_B(cb,tv) ((tv)= GETIL_B((cb))) |
9c344a42 |
745 | #define GET_W(cb,tv) ((tv)=0,(tv)|=(GETIL_B((cb))<<8), (tv)|=GETIL_B(cb), (tv)) |
746 | #define GET_L(cb,tv) ( (tv)=0, \ |
747 | (tv)|=(GETIL_B((cb))<<24), \ |
748 | (tv)|=(GETIL_B((cb))<<16), \ |
749 | (tv)|=(GETIL_B((cb))<<8), \ |
750 | (tv)|=GETIL_B(cb), \ |
2c7b101b |
751 | (tv) ) |
5c596e4d |
752 | |
dfdbb32c |
753 | #endif |