3
* - overall query management (allocation, completion)
4
* - per-query memory management
5
* - query submission and cancellation (user-visible and internal)
9
* Copyright (C) 1997-2000 Ian Jackson <ian@davenant.greenend.org.uk>
11
* It is part of adns, which is
12
* Copyright (C) 1997-2000 Ian Jackson <ian@davenant.greenend.org.uk>
13
* Copyright (C) 1999-2000 Tony Finch <dot@dotat.at>
15
* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2, or (at your option)
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* 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
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* GNU General Public License for more details.
25
* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software Foundation,
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* Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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static adns_query query_alloc(adns_state ads, const typeinfo *typei,
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)); if (!qu->answer) { free(qu); return 0; }
49
qu->state= query_tosend;
50
qu->back= qu->next= qu->parent= 0;
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LIST_INIT(qu->children);
52
LINK_INIT(qu->siblings);
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LIST_INIT(qu->allocations);
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qu->interim_allocd= 0;
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qu->preserved_allocd= 0;
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qu->final_allocspace= 0;
61
adns__vbuf_init(&qu->vb);
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qu->cname_dglen= qu->cname_begin= 0;
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adns__vbuf_init(&qu->search_vb);
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qu->search_origlen= qu->search_pos= qu->search_doneabs= 0;
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qu->id= -2; /* will be overwritten with real id before we leave adns */
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timerclear(&qu->timeout);
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qu->expires= now.tv_sec + MAXTTLBELIEVE;
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memset(&qu->ctx,0,sizeof(qu->ctx));
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qu->answer->status= adns_s_ok;
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qu->answer->cname= qu->answer->owner= 0;
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qu->answer->type= typei->type;
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qu->answer->expires= -1;
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qu->answer->rrs.untyped= 0;
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qu->answer->rrsz= typei->rrsz;
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static void query_submit(adns_state ads, adns_query qu,
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const typeinfo *typei, vbuf *qumsg_vb, int id,
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adns_queryflags flags, struct timeval now) {
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/* Fills in the query message in for a previously-allocated query,
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* and submits it. Cannot fail. Takes over the memory for qumsg_vb.
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adns__vbuf_init(qumsg_vb);
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qu->query_dgram= malloc(qu->vb.used);
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if (!qu->query_dgram) { adns__query_fail(qu,adns_s_nomemory); return; }
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qu->query_dglen= qu->vb.used;
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memcpy(qu->query_dgram,qu->vb.buf,qu->vb.used);
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adns__query_send(qu,now);
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adns_status adns__internal_submit(adns_state ads, adns_query *query_r,
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const typeinfo *typei, vbuf *qumsg_vb, int id,
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adns_queryflags flags, struct timeval now,
113
const qcontext *ctx) {
116
qu= query_alloc(ads,typei,flags,now);
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if (!qu) { adns__vbuf_free(qumsg_vb); return adns_s_nomemory; }
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memcpy(&qu->ctx,ctx,sizeof(qu->ctx));
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query_submit(ads,qu, typei,qumsg_vb,id,flags,now);
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static void query_simple(adns_state ads, adns_query qu,
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const char *owner, int ol,
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const typeinfo *typei, adns_queryflags flags,
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struct timeval now) {
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stat= adns__mkquery(ads,&qu->vb,&id, owner,ol, typei,flags);
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if (stat == adns_s_querydomaintoolong && (flags & adns_qf_search)) {
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adns__search_next(ads,qu,now);
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adns__query_fail(qu,stat);
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adns__vbuf_init(&qu->vb);
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query_submit(ads,qu, typei,&vb_new,id, flags,now);
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void adns__search_next(adns_state ads, adns_query qu, struct timeval now) {
151
const char *nextentry;
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if (qu->search_doneabs<0) {
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qu->search_doneabs= 1;
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if (qu->search_pos >= ads->nsearchlist) {
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if (qu->search_doneabs) {
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stat= adns_s_nxdomain; goto x_fail;
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qu->search_doneabs= 1;
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nextentry= ads->searchlist[qu->search_pos++];
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qu->search_vb.used= qu->search_origlen;
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if (!adns__vbuf_append(&qu->search_vb,".",1) ||
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!adns__vbuf_appendstr(&qu->search_vb,nextentry)) {
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stat= adns_s_nomemory; goto x_fail;
179
free(qu->query_dgram);
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qu->query_dgram= 0; qu->query_dglen= 0;
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query_simple(ads,qu, qu->search_vb.buf, qu->search_vb.used, qu->typei, qu->flags, now);
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adns__query_fail(qu,stat);
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static int save_owner(adns_query qu, const char *owner, int ol) {
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/* Returns 1 if OK, otherwise there was no memory. */
196
ans->owner= adns__alloc_preserved(qu,ol+1); if (!ans->owner) return 0;
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memcpy(ans->owner,owner,ol);
203
int adns_submit(adns_state ads,
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adns_queryflags flags,
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adns_query *query_r) {
211
const typeinfo *typei;
216
adns__consistency(ads,0,cc_entex);
218
typei= adns__findtype(type);
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if (!typei) return ENOSYS;
221
r= gettimeofday(&now,0); if (r) goto x_errno;
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qu= query_alloc(ads,typei,flags,now); if (!qu) goto x_errno;
224
qu->ctx.ext= context;
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memset(&qu->ctx.info,0,sizeof(qu->ctx.info));
231
if (!ol) { stat= adns_s_querydomaininvalid; goto x_adnsfail; }
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if (ol>DNS_MAXDOMAIN+1) { stat= adns_s_querydomaintoolong; goto x_adnsfail; }
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if (ol>=1 && owner[ol-1]=='.' && (ol<2 || owner[ol-2]!='\\')) {
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flags &= ~adns_qf_search;
240
if (flags & adns_qf_search) {
241
r= adns__vbuf_append(&qu->search_vb,owner,ol);
242
if (!r) { stat= adns_s_nomemory; goto x_adnsfail; }
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for (ndots=0, p=owner; (p= strchr(p,'.')); p++, ndots++);
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qu->search_doneabs= (ndots >= ads->searchndots) ? -1 : 0;
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qu->search_origlen= ol;
247
adns__search_next(ads,qu,now);
249
if (flags & adns_qf_owner) {
250
if (!save_owner(qu,owner,ol)) { stat= adns_s_nomemory; goto x_adnsfail; }
252
query_simple(ads,qu, owner,ol, typei,flags, now);
254
adns__autosys(ads,now);
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adns__consistency(ads,qu,cc_entex);
259
adns__query_fail(qu,stat);
260
adns__consistency(ads,qu,cc_entex);
266
adns__consistency(ads,0,cc_entex);
270
int adns_submit_reverse_any(adns_state ads,
271
const struct sockaddr *addr,
274
adns_queryflags flags,
276
adns_query *query_r) {
277
const unsigned char *iaddr;
278
char *buf, *buf_free;
282
flags &= ~adns_qf_search;
284
if (addr->sa_family != AF_INET) return ENOSYS;
285
iaddr= (const unsigned char*) &(((const struct sockaddr_in*)addr) -> sin_addr);
287
lreq= strlen(zone) + 4*4 + 1;
288
if (lreq > sizeof(shortbuf)) {
289
buf= malloc(strlen(zone) + 4*4 + 1);
290
if (!buf) return errno;
296
sprintf(buf, "%d.%d.%d.%d.%s", iaddr[3], iaddr[2], iaddr[1], iaddr[0], zone);
298
r= adns_submit(ads,buf,type,flags,context,query_r);
303
int adns_submit_reverse(adns_state ads,
304
const struct sockaddr *addr,
306
adns_queryflags flags,
308
adns_query *query_r) {
309
if (type != adns_r_ptr && type != adns_r_ptr_raw) return EINVAL;
310
return adns_submit_reverse_any(ads,addr,"in-addr.arpa",type,flags,context,query_r);
313
int adns_synchronous(adns_state ads,
316
adns_queryflags flags,
317
adns_answer **answer_r) {
321
r= adns_submit(ads,owner,type,flags,0,&qu);
324
r= adns_wait(ads,&qu,answer_r,0);
325
if (r) adns_cancel(qu);
330
static void *alloc_common(adns_query qu, size_t sz) {
333
if (!sz) return qu; /* Any old pointer will do */
334
assert(!qu->final_allocspace);
335
an= malloc(MEM_ROUND(MEM_ROUND(sizeof(*an)) + sz));
337
LIST_LINK_TAIL(qu->allocations,an);
338
return (byte*)an + MEM_ROUND(sizeof(*an));
341
void *adns__alloc_interim(adns_query qu, size_t sz) {
345
rv= alloc_common(qu,sz);
347
qu->interim_allocd += sz;
351
void *adns__alloc_preserved(adns_query qu, size_t sz) {
355
rv= adns__alloc_interim(qu,sz);
357
qu->preserved_allocd += sz;
361
void *adns__alloc_mine(adns_query qu, size_t sz) {
362
return alloc_common(qu,MEM_ROUND(sz));
365
void adns__transfer_interim(adns_query from, adns_query to, void *block, size_t sz) {
369
an= (void*)((byte*)block - MEM_ROUND(sizeof(*an)));
371
assert(!to->final_allocspace);
372
assert(!from->final_allocspace);
374
LIST_UNLINK(from->allocations,an);
375
LIST_LINK_TAIL(to->allocations,an);
378
from->interim_allocd -= sz;
379
to->interim_allocd += sz;
381
if (to->expires > from->expires) to->expires= from->expires;
384
void *adns__alloc_final(adns_query qu, size_t sz) {
385
/* When we're in the _final stage, we _subtract_ from interim_alloc'd
386
* each allocation, and use final_allocspace to point to the next free
392
rp= qu->final_allocspace;
394
qu->interim_allocd -= sz;
395
assert(qu->interim_allocd>=0);
396
qu->final_allocspace= (byte*)rp + sz;
400
static void cancel_children(adns_query qu) {
401
adns_query cqu, ncqu;
403
for (cqu= qu->children.head; cqu; cqu= ncqu) {
404
ncqu= cqu->siblings.next;
409
void adns__reset_preserved(adns_query qu) {
410
assert(!qu->final_allocspace);
413
qu->answer->rrs.untyped= 0;
414
qu->interim_allocd= qu->preserved_allocd;
417
static void free_query_allocs(adns_query qu) {
421
for (an= qu->allocations.head; an; an= ann) { ann= an->next; free(an); }
422
LIST_INIT(qu->allocations);
423
adns__vbuf_free(&qu->vb);
424
adns__vbuf_free(&qu->search_vb);
425
free(qu->query_dgram);
429
void adns_cancel(adns_query qu) {
433
adns__consistency(ads,qu,cc_entex);
434
if (qu->parent) LIST_UNLINK_PART(qu->parent->children,qu,siblings.);
437
LIST_UNLINK(ads->udpw,qu);
440
LIST_UNLINK(ads->tcpw,qu);
443
LIST_UNLINK(ads->childw,qu);
446
LIST_UNLINK(ads->output,qu);
451
free_query_allocs(qu);
454
adns__consistency(ads,0,cc_entex);
457
void adns__update_expires(adns_query qu, unsigned long ttl, struct timeval now) {
460
assert(ttl <= MAXTTLBELIEVE);
461
max= now.tv_sec + ttl;
462
if (qu->expires < max) return;
466
static void makefinal_query(adns_query qu) {
472
if (qu->interim_allocd) {
473
ans= realloc(qu->answer, MEM_ROUND(MEM_ROUND(sizeof(*ans)) + qu->interim_allocd));
474
if (!ans) goto x_nomem;
478
qu->final_allocspace= (byte*)ans + MEM_ROUND(sizeof(*ans));
479
adns__makefinal_str(qu,&ans->cname);
480
adns__makefinal_str(qu,&ans->owner);
483
adns__makefinal_block(qu, &ans->rrs.untyped, ans->nrrs*ans->rrsz);
485
for (rrn=0; rrn<ans->nrrs; rrn++)
486
qu->typei->makefinal(qu, ans->rrs.bytes + rrn*ans->rrsz);
489
free_query_allocs(qu);
493
qu->preserved_allocd= 0;
494
qu->answer->cname= 0;
495
qu->answer->owner= 0;
496
adns__reset_preserved(qu); /* (but we just threw away the preserved stuff) */
498
qu->answer->status= adns_s_nomemory;
499
free_query_allocs(qu);
502
void adns__query_done(adns_query qu) {
511
if (qu->flags & adns_qf_owner && qu->flags & adns_qf_search &&
512
ans->status != adns_s_nomemory) {
513
if (!save_owner(qu, qu->search_vb.buf, qu->search_vb.used)) {
514
adns__query_fail(qu,adns_s_nomemory);
519
if (ans->nrrs && qu->typei->diff_needswap) {
520
if (!adns__vbuf_ensure(&qu->vb,qu->typei->rrsz)) {
521
adns__query_fail(qu,adns_s_nomemory);
524
adns__isort(ans->rrs.bytes, ans->nrrs, ans->rrsz,
526
(int(*)(void*, const void*, const void*))qu->typei->diff_needswap,
530
ans->expires= qu->expires;
533
LIST_UNLINK_PART(parent->children,qu,siblings.);
534
LIST_UNLINK(qu->ads->childw,parent);
535
qu->ctx.callback(parent,qu);
536
free_query_allocs(qu);
541
LIST_LINK_TAIL(qu->ads->output,qu);
542
qu->state= query_done;
546
void adns__query_fail(adns_query qu, adns_status stat) {
547
adns__reset_preserved(qu);
548
qu->answer->status= stat;
549
adns__query_done(qu);
552
void adns__makefinal_str(adns_query qu, char **strp) {
554
char *before, *after;
559
after= adns__alloc_final(qu,l);
560
memcpy(after,before,l);
564
void adns__makefinal_block(adns_query qu, void **blpp, size_t sz) {
565
void *before, *after;
569
after= adns__alloc_final(qu,sz);
570
memcpy(after,before,sz);