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 if (flags & adns__qf_nosend)
110 else if (typei->query_send && !(flags & adns__qf_senddirect))
111 typei->query_send(qu,now);
113 adns__query_send(qu, now);
116 adns_status adns__internal_submit(adns_state ads, adns_query *query_r,
117 const typeinfo *typei, adns_rrtype type,
118 vbuf *qumsg_vb, int id,
119 adns_queryflags flags, struct timeval now,
120 const qcontext *ctx) {
123 qu= query_alloc(ads,typei,type,flags & ~adns__qf_nosend,now);
124 if (!qu) { adns__vbuf_free(qumsg_vb); return adns_s_nomemory; }
127 memcpy(&qu->ctx,ctx,sizeof(qu->ctx));
128 query_submit(ads,qu, typei,qumsg_vb,id,flags,now);
133 static void query_simple(adns_state ads, adns_query qu,
134 const char *owner, int ol,
135 const typeinfo *typei, adns_queryflags flags,
136 struct timeval now) {
141 stat= adns__mkquery(ads,&qu->vb,&id, owner,ol,
142 typei,qu->answer->type, flags);
144 if (stat == adns_s_querydomaintoolong && (flags & adns_qf_search)) {
145 adns__search_next(ads,qu,now);
148 adns__query_fail(qu,stat);
154 adns__vbuf_init(&qu->vb);
155 query_submit(ads,qu, typei,&vb_new,id, flags,now);
158 void adns__search_next(adns_state ads, adns_query qu, struct timeval now) {
159 const char *nextentry;
162 if (qu->search_doneabs<0) {
164 qu->search_doneabs= 1;
166 if (qu->search_pos >= ads->nsearchlist) {
167 if (qu->search_doneabs) {
168 qu->search_vb.used= qu->search_origlen;
169 stat= adns_s_nxdomain; goto x_fail;
172 qu->search_doneabs= 1;
175 nextentry= ads->searchlist[qu->search_pos++];
179 qu->search_vb.used= qu->search_origlen;
181 if (!adns__vbuf_append(&qu->search_vb,".",1) ||
182 !adns__vbuf_appendstr(&qu->search_vb,nextentry))
186 free(qu->query_dgram);
187 qu->query_dgram= 0; qu->query_dglen= 0;
189 query_simple(ads,qu, qu->search_vb.buf, qu->search_vb.used,
190 qu->typei, qu->flags, now);
194 stat= adns_s_nomemory;
196 adns__query_fail(qu,stat);
199 static int save_owner(adns_query qu, const char *owner, int ol) {
200 /* Returns 1 if OK, otherwise there was no memory. */
203 if (!(qu->flags & adns_qf_owner)) return 1;
208 ans->owner= adns__alloc_preserved(qu,ol+1); if (!ans->owner) return 0;
210 memcpy(ans->owner,owner,ol);
215 int adns_submit(adns_state ads,
218 adns_queryflags flags,
220 adns_query *query_r) {
223 const typeinfo *typei;
228 adns__consistency(ads,0,cc_entex);
230 if (!(type & adns__qtf_bigaddr) || !(type & adns__qtf_manyaf))
231 flags = (flags & ~adns__qf_afmask) | adns_qf_ipv4_only;
233 typei= adns__findtype(type);
234 if (!typei) return ENOSYS;
236 r= gettimeofday(&now,0); if (r) goto x_errno;
237 qu= query_alloc(ads,typei,type,flags,now); if (!qu) goto x_errno;
239 qu->ctx.ext= context;
241 memset(&qu->ctx.info,0,sizeof(qu->ctx.info));
246 if (!ol) { stat= adns_s_querydomaininvalid; goto x_adnsfail; }
247 if (ol>DNS_MAXDOMAIN+1) { stat= adns_s_querydomaintoolong; goto x_adnsfail; }
249 if (ol>=1 && owner[ol-1]=='.' && (ol<2 || owner[ol-2]!='\\')) {
250 flags &= ~adns_qf_search;
255 if (flags & adns_qf_search) {
256 r= adns__vbuf_append(&qu->search_vb,owner,ol);
257 if (!r) { stat= adns_s_nomemory; goto x_adnsfail; }
259 for (ndots=0, p=owner; (p= strchr(p,'.')); p++, ndots++);
260 qu->search_doneabs= (ndots >= ads->searchndots) ? -1 : 0;
261 qu->search_origlen= ol;
262 adns__search_next(ads,qu,now);
264 if (flags & adns_qf_owner) {
265 if (!save_owner(qu,owner,ol)) { stat= adns_s_nomemory; goto x_adnsfail; }
267 query_simple(ads,qu, owner,ol, typei,flags, now);
269 adns__autosys(ads,now);
270 adns__consistency(ads,qu,cc_entex);
274 adns__query_fail(qu,stat);
275 adns__consistency(ads,qu,cc_entex);
281 adns__consistency(ads,0,cc_entex);
285 static const char *default_zone = "<magic>";
287 int adns_submit_reverse_any(adns_state ads,
288 const struct sockaddr *addr,
291 adns_queryflags flags,
293 adns_query *query_r) {
294 char *buf, *buf_free, *p;
299 flags &= ~adns_qf_search;
301 switch (addr->sa_family) {
303 ai = &adns__inet_afinfo;
304 if (zone == default_zone) zone = "in-addr.arpa";
307 ai = &adns__inet6_afinfo;
308 if (zone == default_zone) zone = "ip6.arpa";
314 lreq= strlen(zone) + ai->nrevcomp*(ai->revcompwd + 1) + 1;
315 if (lreq > sizeof(shortbuf)) {
317 if (!buf) return errno;
324 p = ai->rev_mkname(addr, buf);
328 r= adns_submit(ads,buf,type,flags,context,query_r);
333 int adns_submit_reverse(adns_state ads,
334 const struct sockaddr *addr,
336 adns_queryflags flags,
338 adns_query *query_r) {
339 if (type != adns_r_ptr && type != adns_r_ptr_raw) return EINVAL;
340 return adns_submit_reverse_any(ads,addr,default_zone,
341 type,flags,context,query_r);
344 int adns_synchronous(adns_state ads,
347 adns_queryflags flags,
348 adns_answer **answer_r) {
352 r= adns_submit(ads,owner,type,flags,0,&qu);
355 r= adns_wait(ads,&qu,answer_r,0);
356 if (r) adns_cancel(qu);
361 static void *alloc_common(adns_query qu, size_t sz) {
364 if (!sz) return qu; /* Any old pointer will do */
365 assert(!qu->final_allocspace);
366 an= malloc(MEM_ROUND(MEM_ROUND(sizeof(*an)) + sz));
368 LIST_LINK_TAIL(qu->allocations,an);
370 return (byte*)an + MEM_ROUND(sizeof(*an));
373 void *adns__alloc_interim(adns_query qu, size_t sz) {
377 rv= alloc_common(qu,sz);
379 qu->interim_allocd += sz;
383 void *adns__alloc_preserved(adns_query qu, size_t sz) {
387 rv= adns__alloc_interim(qu,sz);
389 qu->preserved_allocd += sz;
393 static allocnode *alloc_info(void *p, size_t *sz_r)
397 if (!p) { *sz_r = 0; return 0; }
398 an = (allocnode *)((byte *)p - MEM_ROUND(sizeof(allocnode)));
399 *sz_r = MEM_ROUND(an->sz);
403 void adns__free_interim(adns_query qu, void *p) {
405 allocnode *an = alloc_info(p, &sz);
408 assert(!qu->final_allocspace);
409 LIST_UNLINK(qu->allocations, an);
411 qu->interim_allocd -= sz;
414 void *adns__alloc_mine(adns_query qu, size_t sz) {
415 return alloc_common(qu,MEM_ROUND(sz));
418 void adns__transfer_interim(adns_query from, adns_query to, void *block) {
420 allocnode *an = alloc_info(block, &sz);
424 assert(!to->final_allocspace);
425 assert(!from->final_allocspace);
427 LIST_UNLINK(from->allocations,an);
428 LIST_LINK_TAIL(to->allocations,an);
430 from->interim_allocd -= sz;
431 to->interim_allocd += sz;
433 if (to->expires > from->expires) to->expires= from->expires;
436 void *adns__alloc_final(adns_query qu, size_t sz) {
437 /* When we're in the _final stage, we _subtract_ from interim_alloc'd
438 * each allocation, and use final_allocspace to point to the next free
444 rp= qu->final_allocspace;
446 qu->interim_allocd -= sz;
447 assert(qu->interim_allocd>=0);
448 qu->final_allocspace= (byte*)rp + sz;
452 void adns__cancel_children(adns_query qu) {
453 adns_query cqu, ncqu;
455 for (cqu= qu->children.head; cqu; cqu= ncqu) {
456 ncqu= cqu->siblings.next;
461 void adns__reset_preserved(adns_query qu) {
462 assert(!qu->final_allocspace);
463 adns__cancel_children(qu);
465 qu->answer->rrs.untyped= 0;
466 qu->interim_allocd= qu->preserved_allocd;
469 static void free_query_allocs(adns_query qu) {
472 adns__cancel_children(qu);
473 for (an= qu->allocations.head; an; an= ann) { ann= an->next; free(an); }
474 LIST_INIT(qu->allocations);
475 adns__vbuf_free(&qu->vb);
476 adns__vbuf_free(&qu->search_vb);
477 free(qu->query_dgram);
481 void adns_cancel(adns_query qu) {
485 adns__consistency(ads,qu,cc_entex);
486 if (qu->parent) LIST_UNLINK_PART(qu->parent->children,qu,siblings.);
489 LIST_UNLINK(ads->udpw,qu);
492 LIST_UNLINK(ads->tcpw,qu);
495 LIST_UNLINK(ads->childw,qu);
498 LIST_UNLINK(ads->output,qu);
503 free_query_allocs(qu);
506 adns__consistency(ads,0,cc_entex);
509 void adns__update_expires(adns_query qu, unsigned long ttl,
510 struct timeval now) {
513 assert(ttl <= MAXTTLBELIEVE);
514 max= now.tv_sec + ttl;
515 if (qu->expires < max) return;
519 static void makefinal_query(adns_query qu) {
525 if (qu->interim_allocd) {
526 ans= realloc(qu->answer,
527 MEM_ROUND(MEM_ROUND(sizeof(*ans)) + qu->interim_allocd));
528 if (!ans) goto x_nomem;
532 qu->final_allocspace= (byte*)ans + MEM_ROUND(sizeof(*ans));
533 adns__makefinal_str(qu,&ans->cname);
534 adns__makefinal_str(qu,&ans->owner);
537 adns__makefinal_block(qu, &ans->rrs.untyped, ans->nrrs*ans->rrsz);
539 for (rrn=0; rrn<ans->nrrs; rrn++)
540 qu->typei->makefinal(qu, ans->rrs.bytes + rrn*ans->rrsz);
543 free_query_allocs(qu);
547 qu->preserved_allocd= 0;
548 qu->answer->cname= 0;
549 qu->answer->owner= 0;
550 adns__reset_preserved(qu); /* (but we just threw away the preserved stuff) */
552 qu->answer->status= adns_s_nomemory;
553 free_query_allocs(qu);
556 void adns__query_done(adns_query qu) {
560 adns__cancel_children(qu);
565 if (qu->flags & adns_qf_search && ans->status != adns_s_nomemory) {
566 if (!save_owner(qu, qu->search_vb.buf, qu->search_vb.used)) {
567 adns__query_fail(qu,adns_s_nomemory);
572 if (ans->nrrs && qu->typei->diff_needswap) {
573 if (!adns__vbuf_ensure(&qu->vb,ans->rrsz)) {
574 adns__query_fail(qu,adns_s_nomemory);
577 adns__isort(ans->rrs.bytes, ans->nrrs, ans->rrsz,
579 (int(*)(void*, const void*, const void*))
580 qu->typei->diff_needswap,
583 if (ans->nrrs && qu->typei->postsort) {
584 qu->typei->postsort(qu->ads, ans->rrs.bytes, ans->nrrs, qu->typei);
587 ans->expires= qu->expires;
590 LIST_UNLINK_PART(parent->children,qu,siblings.);
591 LIST_UNLINK(qu->ads->childw,parent);
592 qu->ctx.callback(parent,qu);
593 free_query_allocs(qu);
598 LIST_LINK_TAIL(qu->ads->output,qu);
599 qu->state= query_done;
603 void adns__query_fail(adns_query qu, adns_status stat) {
604 adns__reset_preserved(qu);
605 qu->answer->status= stat;
606 adns__query_done(qu);
609 void adns__makefinal_str(adns_query qu, char **strp) {
611 char *before, *after;
616 after= adns__alloc_final(qu,l);
617 memcpy(after,before,l);
621 void adns__makefinal_block(adns_query qu, void **blpp, size_t sz) {
622 void *before, *after;
626 after= adns__alloc_final(qu,sz);
627 memcpy(after,before,sz);