3 * - overall query management (allocation, completion)
4 * - per-query memory management
5 * - query submission and cancellation (user-visible and internal)
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.)
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)
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.
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,
26 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
39 static adns_query query_alloc(adns_state ads,
40 const typeinfo *typei, adns_rrtype type,
41 adns_queryflags flags, struct timeval now) {
42 /* Allocate a virgin query and return it. */
45 qu= malloc(sizeof(*qu)); if (!qu) return 0;
46 qu->answer= malloc(sizeof(*qu->answer));
47 if (!qu->answer) { free(qu); return 0; }
50 qu->state= query_tosend;
51 qu->back= qu->next= qu->parent= 0;
52 LIST_INIT(qu->children);
53 LINK_INIT(qu->siblings);
54 LIST_INIT(qu->allocations);
55 qu->interim_allocd= 0;
56 qu->preserved_allocd= 0;
57 qu->final_allocspace= 0;
62 adns__vbuf_init(&qu->vb);
65 qu->cname_dglen= qu->cname_begin= 0;
67 adns__vbuf_init(&qu->search_vb);
68 qu->search_origlen= qu->search_pos= qu->search_doneabs= 0;
70 qu->id= -2; /* will be overwritten with real id before we leave adns */
75 timerclear(&qu->timeout);
76 qu->expires= now.tv_sec + MAXTTLBELIEVE;
78 memset(&qu->ctx,0,sizeof(qu->ctx));
80 qu->answer->status= adns_s_ok;
81 qu->answer->cname= qu->answer->owner= 0;
82 qu->answer->type= type;
83 qu->answer->expires= -1;
85 qu->answer->rrs.untyped= 0;
86 qu->answer->rrsz= typei->rrsz;
91 static void query_submit(adns_state ads, adns_query qu,
92 const typeinfo *typei, vbuf *qumsg_vb, int id,
93 adns_queryflags flags, struct timeval now) {
94 /* Fills in the query message in for a previously-allocated query,
95 * and submits it. Cannot fail. Takes over the memory for qumsg_vb.
99 adns__vbuf_init(qumsg_vb);
101 qu->query_dgram= malloc(qu->vb.used);
102 if (!qu->query_dgram) { adns__query_fail(qu,adns_s_nomemory); return; }
105 qu->query_dglen= qu->vb.used;
106 memcpy(qu->query_dgram,qu->vb.buf,qu->vb.used);
108 adns__query_send(qu,now);
111 adns_status adns__internal_submit(adns_state ads, adns_query *query_r,
112 const typeinfo *typei, vbuf *qumsg_vb,
114 adns_queryflags flags, struct timeval now,
115 const qcontext *ctx) {
118 qu= query_alloc(ads,typei,typei->typekey,flags,now);
119 if (!qu) { adns__vbuf_free(qumsg_vb); return adns_s_nomemory; }
122 memcpy(&qu->ctx,ctx,sizeof(qu->ctx));
123 query_submit(ads,qu, typei,qumsg_vb,id,flags,now);
128 static void query_simple(adns_state ads, adns_query qu,
129 const char *owner, int ol,
130 const typeinfo *typei, adns_queryflags flags,
131 struct timeval now) {
136 stat= adns__mkquery(ads,&qu->vb,&id, owner,ol,
137 typei,qu->answer->type, flags);
139 if (stat == adns_s_querydomaintoolong && (flags & adns_qf_search)) {
140 adns__search_next(ads,qu,now);
143 adns__query_fail(qu,stat);
149 adns__vbuf_init(&qu->vb);
150 query_submit(ads,qu, typei,&vb_new,id, flags,now);
153 void adns__search_next(adns_state ads, adns_query qu, struct timeval now) {
154 const char *nextentry;
157 if (qu->search_doneabs<0) {
159 qu->search_doneabs= 1;
161 if (qu->search_pos >= ads->nsearchlist) {
162 if (qu->search_doneabs) {
163 qu->search_vb.used= qu->search_origlen;
164 stat= adns_s_nxdomain; goto x_fail;
167 qu->search_doneabs= 1;
170 nextentry= ads->searchlist[qu->search_pos++];
174 qu->search_vb.used= qu->search_origlen;
176 if (!adns__vbuf_append(&qu->search_vb,".",1) ||
177 !adns__vbuf_appendstr(&qu->search_vb,nextentry))
181 free(qu->query_dgram);
182 qu->query_dgram= 0; qu->query_dglen= 0;
184 query_simple(ads,qu, qu->search_vb.buf, qu->search_vb.used,
185 qu->typei, qu->flags, now);
189 stat= adns_s_nomemory;
191 adns__query_fail(qu,stat);
194 static int save_owner(adns_query qu, const char *owner, int ol) {
195 /* Returns 1 if OK, otherwise there was no memory. */
198 if (!(qu->flags & adns_qf_owner)) return 1;
203 ans->owner= adns__alloc_preserved(qu,ol+1); if (!ans->owner) return 0;
205 memcpy(ans->owner,owner,ol);
210 int adns_submit(adns_state ads,
213 adns_queryflags flags,
215 adns_query *query_r) {
218 const typeinfo *typei;
223 adns__consistency(ads,0,cc_entex);
225 typei= adns__findtype(type);
226 if (!typei) return ENOSYS;
228 r= gettimeofday(&now,0); if (r) goto x_errno;
229 qu= query_alloc(ads,typei,type,flags,now); if (!qu) goto x_errno;
231 qu->ctx.ext= context;
233 memset(&qu->ctx.info,0,sizeof(qu->ctx.info));
238 if (!ol) { stat= adns_s_querydomaininvalid; goto x_adnsfail; }
239 if (ol>DNS_MAXDOMAIN+1) { stat= adns_s_querydomaintoolong; goto x_adnsfail; }
241 if (ol>=1 && owner[ol-1]=='.' && (ol<2 || owner[ol-2]!='\\')) {
242 flags &= ~adns_qf_search;
247 if (flags & adns_qf_search) {
248 r= adns__vbuf_append(&qu->search_vb,owner,ol);
249 if (!r) { stat= adns_s_nomemory; goto x_adnsfail; }
251 for (ndots=0, p=owner; (p= strchr(p,'.')); p++, ndots++);
252 qu->search_doneabs= (ndots >= ads->searchndots) ? -1 : 0;
253 qu->search_origlen= ol;
254 adns__search_next(ads,qu,now);
256 if (flags & adns_qf_owner) {
257 if (!save_owner(qu,owner,ol)) { stat= adns_s_nomemory; goto x_adnsfail; }
259 query_simple(ads,qu, owner,ol, typei,flags, now);
261 adns__autosys(ads,now);
262 adns__consistency(ads,qu,cc_entex);
266 adns__query_fail(qu,stat);
267 adns__consistency(ads,qu,cc_entex);
273 adns__consistency(ads,0,cc_entex);
277 static const char *default_zone = "<magic>";
279 int adns_submit_reverse_any(adns_state ads,
280 const struct sockaddr *addr,
283 adns_queryflags flags,
285 adns_query *query_r) {
286 char *buf, *buf_free, *p;
291 flags &= ~adns_qf_search;
293 switch (addr->sa_family) {
295 ai = &adns__inet_afinfo;
296 if (zone == default_zone) zone = "in-addr.arpa";
299 ai = &adns__inet6_afinfo;
300 if (zone == default_zone) zone = "ip6.arpa";
306 lreq= strlen(zone) + ai->nrevcomp*(ai->revcompwd + 1) + 1;
307 if (lreq > sizeof(shortbuf)) {
309 if (!buf) return errno;
316 p = ai->rev_mkname(addr, buf);
320 r= adns_submit(ads,buf,type,flags,context,query_r);
325 int adns_submit_reverse(adns_state ads,
326 const struct sockaddr *addr,
328 adns_queryflags flags,
330 adns_query *query_r) {
331 if (type != adns_r_ptr && type != adns_r_ptr_raw) return EINVAL;
332 return adns_submit_reverse_any(ads,addr,default_zone,
333 type,flags,context,query_r);
336 int adns_synchronous(adns_state ads,
339 adns_queryflags flags,
340 adns_answer **answer_r) {
344 r= adns_submit(ads,owner,type,flags,0,&qu);
347 r= adns_wait(ads,&qu,answer_r,0);
348 if (r) adns_cancel(qu);
353 static void *alloc_common(adns_query qu, size_t sz) {
356 if (!sz) return qu; /* Any old pointer will do */
357 assert(!qu->final_allocspace);
358 an= malloc(MEM_ROUND(MEM_ROUND(sizeof(*an)) + sz));
360 LIST_LINK_TAIL(qu->allocations,an);
361 return (byte*)an + MEM_ROUND(sizeof(*an));
364 void *adns__alloc_interim(adns_query qu, size_t sz) {
368 rv= alloc_common(qu,sz);
370 qu->interim_allocd += sz;
374 void *adns__alloc_preserved(adns_query qu, size_t sz) {
378 rv= adns__alloc_interim(qu,sz);
380 qu->preserved_allocd += sz;
384 void *adns__alloc_mine(adns_query qu, size_t sz) {
385 return alloc_common(qu,MEM_ROUND(sz));
388 void adns__transfer_interim(adns_query from, adns_query to,
389 void *block, size_t sz) {
393 an= (void*)((byte*)block - MEM_ROUND(sizeof(*an)));
395 assert(!to->final_allocspace);
396 assert(!from->final_allocspace);
398 LIST_UNLINK(from->allocations,an);
399 LIST_LINK_TAIL(to->allocations,an);
402 from->interim_allocd -= sz;
403 to->interim_allocd += sz;
405 if (to->expires > from->expires) to->expires= from->expires;
408 void *adns__alloc_final(adns_query qu, size_t sz) {
409 /* When we're in the _final stage, we _subtract_ from interim_alloc'd
410 * each allocation, and use final_allocspace to point to the next free
416 rp= qu->final_allocspace;
418 qu->interim_allocd -= sz;
419 assert(qu->interim_allocd>=0);
420 qu->final_allocspace= (byte*)rp + sz;
424 static void cancel_children(adns_query qu) {
425 adns_query cqu, ncqu;
427 for (cqu= qu->children.head; cqu; cqu= ncqu) {
428 ncqu= cqu->siblings.next;
433 void adns__reset_preserved(adns_query qu) {
434 assert(!qu->final_allocspace);
437 qu->answer->rrs.untyped= 0;
438 qu->interim_allocd= qu->preserved_allocd;
441 static void free_query_allocs(adns_query qu) {
445 for (an= qu->allocations.head; an; an= ann) { ann= an->next; free(an); }
446 LIST_INIT(qu->allocations);
447 adns__vbuf_free(&qu->vb);
448 adns__vbuf_free(&qu->search_vb);
449 free(qu->query_dgram);
453 void adns_cancel(adns_query qu) {
457 adns__consistency(ads,qu,cc_entex);
458 if (qu->parent) LIST_UNLINK_PART(qu->parent->children,qu,siblings.);
461 LIST_UNLINK(ads->udpw,qu);
464 LIST_UNLINK(ads->tcpw,qu);
467 LIST_UNLINK(ads->childw,qu);
470 LIST_UNLINK(ads->output,qu);
475 free_query_allocs(qu);
478 adns__consistency(ads,0,cc_entex);
481 void adns__update_expires(adns_query qu, unsigned long ttl,
482 struct timeval now) {
485 assert(ttl <= MAXTTLBELIEVE);
486 max= now.tv_sec + ttl;
487 if (qu->expires < max) return;
491 static void makefinal_query(adns_query qu) {
497 if (qu->interim_allocd) {
498 ans= realloc(qu->answer,
499 MEM_ROUND(MEM_ROUND(sizeof(*ans)) + qu->interim_allocd));
500 if (!ans) goto x_nomem;
504 qu->final_allocspace= (byte*)ans + MEM_ROUND(sizeof(*ans));
505 adns__makefinal_str(qu,&ans->cname);
506 adns__makefinal_str(qu,&ans->owner);
509 adns__makefinal_block(qu, &ans->rrs.untyped, ans->nrrs*ans->rrsz);
511 for (rrn=0; rrn<ans->nrrs; rrn++)
512 qu->typei->makefinal(qu, ans->rrs.bytes + rrn*ans->rrsz);
515 free_query_allocs(qu);
519 qu->preserved_allocd= 0;
520 qu->answer->cname= 0;
521 qu->answer->owner= 0;
522 adns__reset_preserved(qu); /* (but we just threw away the preserved stuff) */
524 qu->answer->status= adns_s_nomemory;
525 free_query_allocs(qu);
528 void adns__query_done(adns_query qu) {
537 if (qu->flags & adns_qf_search && ans->status != adns_s_nomemory) {
538 if (!save_owner(qu, qu->search_vb.buf, qu->search_vb.used)) {
539 adns__query_fail(qu,adns_s_nomemory);
544 if (ans->nrrs && qu->typei->diff_needswap) {
545 if (!adns__vbuf_ensure(&qu->vb,qu->typei->rrsz)) {
546 adns__query_fail(qu,adns_s_nomemory);
549 adns__isort(ans->rrs.bytes, ans->nrrs, ans->rrsz,
551 (int(*)(void*, const void*, const void*))
552 qu->typei->diff_needswap,
555 if (ans->nrrs && qu->typei->postsort) {
556 qu->typei->postsort(qu->ads, ans->rrs.bytes, ans->nrrs, qu->typei);
559 ans->expires= qu->expires;
562 LIST_UNLINK_PART(parent->children,qu,siblings.);
563 LIST_UNLINK(qu->ads->childw,parent);
564 qu->ctx.callback(parent,qu);
565 free_query_allocs(qu);
570 LIST_LINK_TAIL(qu->ads->output,qu);
571 qu->state= query_done;
575 void adns__query_fail(adns_query qu, adns_status stat) {
576 adns__reset_preserved(qu);
577 qu->answer->status= stat;
578 adns__query_done(qu);
581 void adns__makefinal_str(adns_query qu, char **strp) {
583 char *before, *after;
588 after= adns__alloc_final(qu,l);
589 memcpy(after,before,l);
593 void adns__makefinal_block(adns_query qu, void **blpp, size_t sz) {
594 void *before, *after;
598 after= adns__alloc_final(qu,sz);
599 memcpy(after,before,sz);