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->getrrsz(typei,type);
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 typei->query_send(qu,now);
111 adns_status adns__ckl_hostname(adns_state ads, adns_queryflags flags,
112 union checklabel_state *cls,
113 qcontext *ctx, int labnum,
114 const char *label, int lablen)
118 if (flags & adns_qf_quoteok_query) return adns_s_ok;
119 for (i=0; i<lablen; i++) {
122 if (!i) return adns_s_querydomaininvalid;
123 } else if (!ctype_alpha(c) && !ctype_digit(c)) {
124 return adns_s_querydomaininvalid;
130 static adns_status check_domain_name(adns_state ads, adns_queryflags flags,
131 qcontext *ctx, const typeinfo *typei,
132 const byte *dgram, int dglen)
136 int labnum= 0, labstart, lablen;
137 union checklabel_state cls;
139 adns__findlabel_start(&fls,ads, -1,0, dgram,dglen,dglen, DNS_HDRSIZE,0);
141 err= adns__findlabel_next(&fls, &lablen,&labstart);
142 assert(!err); assert(lablen >= 0);
143 err= typei->checklabel(ads,flags, &cls,ctx,
144 labnum++, dgram+labstart,lablen);
150 adns_status adns__internal_submit(adns_state ads, adns_query *query_r,
152 const typeinfo *typei, adns_rrtype type,
153 vbuf *qumsg_vb, int id,
154 adns_queryflags flags, struct timeval now,
159 err= check_domain_name(ads, flags,ctx,typei, qumsg_vb->buf,qumsg_vb->used);
161 qu= query_alloc(ads,typei,type,flags,now);
162 if (!qu) { err = adns_s_nomemory; goto x_err; }
166 LIST_LINK_TAIL_PART(parent->children,qu,siblings.);
167 memcpy(&qu->ctx,ctx,sizeof(qu->ctx));
168 query_submit(ads,qu, typei,qumsg_vb,id,flags,now);
173 adns__vbuf_free(qumsg_vb);
177 static void query_simple(adns_state ads, adns_query qu,
178 const char *owner, int ol,
179 const typeinfo *typei, adns_queryflags flags,
180 struct timeval now) {
185 stat= adns__mkquery(ads,&qu->vb,&id, owner,ol,
186 typei,qu->answer->type, flags);
188 if (stat == adns_s_querydomaintoolong && (flags & adns_qf_search)) {
189 adns__search_next(ads,qu,now);
192 adns__query_fail(qu,stat);
197 stat= check_domain_name(ads, flags,&qu->ctx,typei, qu->vb.buf,qu->vb.used);
198 if (stat) { adns__query_fail(qu,stat); return; }
201 adns__vbuf_init(&qu->vb);
202 query_submit(ads,qu, typei,&vb_new,id, flags,now);
205 void adns__search_next(adns_state ads, adns_query qu, struct timeval now) {
206 const char *nextentry;
209 if (qu->search_doneabs<0) {
211 qu->search_doneabs= 1;
213 if (qu->search_pos >= ads->nsearchlist) {
214 if (qu->search_doneabs) {
215 qu->search_vb.used= qu->search_origlen;
216 stat= adns_s_nxdomain; goto x_fail;
219 qu->search_doneabs= 1;
222 nextentry= ads->searchlist[qu->search_pos++];
226 qu->search_vb.used= qu->search_origlen;
228 if (!adns__vbuf_append(&qu->search_vb,".",1) ||
229 !adns__vbuf_appendstr(&qu->search_vb,nextentry))
233 free(qu->query_dgram);
234 qu->query_dgram= 0; qu->query_dglen= 0;
236 query_simple(ads,qu, qu->search_vb.buf, qu->search_vb.used,
237 qu->typei, qu->flags, now);
241 stat= adns_s_nomemory;
243 adns__query_fail(qu,stat);
246 static int save_owner(adns_query qu, const char *owner, int ol) {
247 /* Returns 1 if OK, otherwise there was no memory. */
250 if (!(qu->flags & adns_qf_owner)) return 1;
255 ans->owner= adns__alloc_preserved(qu,ol+1); if (!ans->owner) return 0;
257 memcpy(ans->owner,owner,ol);
262 int adns_submit(adns_state ads,
265 adns_queryflags flags,
267 adns_query *query_r) {
270 const typeinfo *typei;
275 adns__consistency(ads,0,cc_entex);
277 typei= adns__findtype(type);
278 if (!typei) return ENOSYS;
280 r= gettimeofday(&now,0); if (r) goto x_errno;
281 qu= query_alloc(ads,typei,type,flags,now); if (!qu) goto x_errno;
283 qu->ctx.ext= context;
285 memset(&qu->ctx.pinfo,0,sizeof(qu->ctx.pinfo));
286 memset(&qu->ctx.tinfo,0,sizeof(qu->ctx.tinfo));
291 if (!ol) { stat= adns_s_querydomaininvalid; goto x_adnsfail; }
292 if (ol>DNS_MAXDOMAIN+1) { stat= adns_s_querydomaintoolong; goto x_adnsfail; }
294 if (ol>=1 && owner[ol-1]=='.' && (ol<2 || owner[ol-2]!='\\')) {
295 flags &= ~adns_qf_search;
300 if (flags & adns_qf_search) {
301 r= adns__vbuf_append(&qu->search_vb,owner,ol);
302 if (!r) { stat= adns_s_nomemory; goto x_adnsfail; }
304 for (ndots=0, p=owner; (p= strchr(p,'.')); p++, ndots++);
305 qu->search_doneabs= (ndots >= ads->searchndots) ? -1 : 0;
306 qu->search_origlen= ol;
307 adns__search_next(ads,qu,now);
309 if (flags & adns_qf_owner) {
310 if (!save_owner(qu,owner,ol)) { stat= adns_s_nomemory; goto x_adnsfail; }
312 query_simple(ads,qu, owner,ol, typei,flags, now);
314 adns__autosys(ads,now);
315 adns__returning(ads,qu);
319 adns__query_fail(qu,stat);
320 adns__returning(ads,qu);
326 adns__returning(ads,0);
330 int adns_submit_reverse_any(adns_state ads,
331 const struct sockaddr *addr,
334 adns_queryflags flags,
336 adns_query *query_r) {
337 char *buf, *buf_free = 0;
341 flags &= ~adns_qf_search;
344 r= adns__make_reverse_domain(addr,zone, &buf,sizeof(shortbuf),&buf_free);
346 r= adns_submit(ads,buf,type,flags,context,query_r);
351 int adns_submit_reverse(adns_state ads,
352 const struct sockaddr *addr,
354 adns_queryflags flags,
356 adns_query *query_r) {
357 if (((type^adns_r_ptr) & adns_rrt_reprmask) &&
358 ((type^adns_r_ptr_raw) & adns_rrt_reprmask))
360 return adns_submit_reverse_any(ads,addr,0,type,flags,context,query_r);
363 int adns_synchronous(adns_state ads,
366 adns_queryflags flags,
367 adns_answer **answer_r) {
371 r= adns_submit(ads,owner,type,flags,0,&qu);
374 r= adns_wait(ads,&qu,answer_r,0);
375 if (r) adns_cancel(qu);
380 static void *alloc_common(adns_query qu, size_t sz) {
383 if (!sz) return qu; /* Any old pointer will do */
384 assert(!qu->final_allocspace);
385 an= malloc(MEM_ROUND(MEM_ROUND(sizeof(*an)) + sz));
387 LIST_LINK_TAIL(qu->allocations,an);
389 return (byte*)an + MEM_ROUND(sizeof(*an));
392 void *adns__alloc_interim(adns_query qu, size_t sz) {
396 rv= alloc_common(qu,sz);
398 qu->interim_allocd += sz;
402 void *adns__alloc_preserved(adns_query qu, size_t sz) {
406 rv= adns__alloc_interim(qu,sz);
408 qu->preserved_allocd += sz;
412 static allocnode *alloc_info(adns_query qu, void *p, size_t *sz_r) {
415 if (!p || p == qu) { *sz_r= 0; return 0; }
416 an= (allocnode *)((byte *)p - MEM_ROUND(sizeof(allocnode)));
417 *sz_r= MEM_ROUND(an->sz);
421 void adns__free_interim(adns_query qu, void *p) {
423 allocnode *an= alloc_info(qu, p, &sz);
426 assert(!qu->final_allocspace);
427 LIST_UNLINK(qu->allocations, an);
429 qu->interim_allocd -= sz;
432 void *adns__alloc_mine(adns_query qu, size_t sz) {
433 return alloc_common(qu,MEM_ROUND(sz));
436 void adns__transfer_interim(adns_query from, adns_query to, void *block) {
438 allocnode *an= alloc_info(from, block, &sz);
442 assert(!to->final_allocspace);
443 assert(!from->final_allocspace);
445 LIST_UNLINK(from->allocations,an);
446 LIST_LINK_TAIL(to->allocations,an);
448 from->interim_allocd -= sz;
449 to->interim_allocd += sz;
451 if (to->expires > from->expires) to->expires= from->expires;
454 void *adns__alloc_final(adns_query qu, size_t sz) {
455 /* When we're in the _final stage, we _subtract_ from interim_alloc'd
456 * each allocation, and use final_allocspace to point to the next free
462 rp= qu->final_allocspace;
464 qu->interim_allocd -= sz;
465 assert(qu->interim_allocd>=0);
466 qu->final_allocspace= (byte*)rp + sz;
470 void adns__cancel_children(adns_query qu) {
471 adns_query cqu, ncqu;
473 for (cqu= qu->children.head; cqu; cqu= ncqu) {
474 ncqu= cqu->siblings.next;
479 void adns__reset_preserved(adns_query qu) {
480 assert(!qu->final_allocspace);
481 adns__cancel_children(qu);
483 qu->answer->rrs.untyped= 0;
484 qu->interim_allocd= qu->preserved_allocd;
487 static void free_query_allocs(adns_query qu) {
490 adns__cancel_children(qu);
491 for (an= qu->allocations.head; an; an= ann) { ann= an->next; free(an); }
492 LIST_INIT(qu->allocations);
493 adns__vbuf_free(&qu->vb);
494 adns__vbuf_free(&qu->search_vb);
495 free(qu->query_dgram);
499 void adns__returning(adns_state ads, adns_query qu_for_caller) {
500 while (ads->intdone.head) {
501 adns_query iq= ads->intdone.head;
502 adns_query parent= iq->parent;
503 LIST_UNLINK_PART(parent->children,iq,siblings.);
504 LIST_UNLINK(iq->ads->childw,parent);
505 LIST_UNLINK(ads->intdone,iq);
506 iq->ctx.callback(parent,iq);
507 free_query_allocs(iq);
511 adns__consistency(ads,qu_for_caller,cc_entex);
514 void adns__cancel(adns_query qu) {
518 adns__consistency(ads,qu,cc_freq);
519 if (qu->parent) LIST_UNLINK_PART(qu->parent->children,qu,siblings.);
522 LIST_UNLINK(ads->udpw,qu);
525 LIST_UNLINK(ads->tcpw,qu);
528 LIST_UNLINK(ads->childw,qu);
532 LIST_UNLINK(ads->intdone,qu);
534 LIST_UNLINK(ads->output,qu);
539 free_query_allocs(qu);
544 void adns_cancel(adns_query qu) {
549 adns__consistency(ads,qu,cc_entex);
551 adns__returning(ads,0);
554 void adns__update_expires(adns_query qu, unsigned long ttl,
555 struct timeval now) {
558 assert(ttl <= MAXTTLBELIEVE);
559 max= now.tv_sec + ttl;
560 if (qu->expires < max) return;
564 static void makefinal_query(adns_query qu) {
570 if (qu->interim_allocd) {
571 ans= realloc(qu->answer,
572 MEM_ROUND(MEM_ROUND(sizeof(*ans)) + qu->interim_allocd));
573 if (!ans) goto x_nomem;
577 qu->final_allocspace= (byte*)ans + MEM_ROUND(sizeof(*ans));
578 adns__makefinal_str(qu,&ans->cname);
579 adns__makefinal_str(qu,&ans->owner);
582 adns__makefinal_block(qu, &ans->rrs.untyped, ans->nrrs*ans->rrsz);
584 for (rrn=0; rrn<ans->nrrs; rrn++)
585 qu->typei->makefinal(qu, ans->rrs.bytes + rrn*ans->rrsz);
588 free_query_allocs(qu);
592 qu->preserved_allocd= 0;
593 qu->answer->cname= 0;
594 qu->answer->owner= 0;
595 adns__reset_preserved(qu); /* (but we just threw away the preserved stuff) */
597 qu->answer->status= adns_s_nomemory;
598 free_query_allocs(qu);
601 void adns__query_done(adns_query qu) {
602 adns_state ads=qu->ads;
605 adns__cancel_children(qu);
610 if (qu->flags & adns_qf_search && ans->status != adns_s_nomemory) {
611 if (!save_owner(qu, qu->search_vb.buf, qu->search_vb.used)) {
612 adns__query_fail(qu,adns_s_nomemory);
617 if (ans->nrrs && qu->typei->diff_needswap) {
618 if (!adns__vbuf_ensure(&qu->vb,qu->answer->rrsz)) {
619 adns__query_fail(qu,adns_s_nomemory);
622 adns__isort(ans->rrs.bytes, ans->nrrs, ans->rrsz,
624 (int(*)(void*, const void*, const void*))
625 qu->typei->diff_needswap,
628 if (ans->nrrs && qu->typei->postsort) {
629 qu->typei->postsort(qu->ads, ans->rrs.bytes,
630 ans->nrrs,ans->rrsz, qu->typei);
633 ans->expires= qu->expires;
634 qu->state= query_done;
636 LIST_LINK_TAIL(ads->intdone,qu);
639 LIST_LINK_TAIL(qu->ads->output,qu);
643 void adns__query_fail(adns_query qu, adns_status stat) {
644 adns__reset_preserved(qu);
645 qu->answer->status= stat;
646 adns__query_done(qu);
649 void adns__makefinal_str(adns_query qu, char **strp) {
651 char *before, *after;
656 after= adns__alloc_final(qu,l);
657 memcpy(after,before,l);
661 void adns__makefinal_block(adns_query qu, void **blpp, size_t sz) {
662 void *before, *after;
666 after= adns__alloc_final(qu,sz);
667 memcpy(after,before,sz);