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NeoStats/adns/query.c
2004-01-14 11:36:37 +00:00

684 lines
15 KiB
C

/* NeoStats - IRC Statistical Services
** Copyright (c) 1999-2004 Adam Rutter, Justin Hammond
** http://www.neostats.net/
**
** This program is free software; you can redistribute it and/or modify
** it under the terms of the GNU General Public License as published by
** the Free Software Foundation; either version 2 of the License, or
** (at your option) any later version.
**
** This program is distributed in the hope that it will be useful,
** but WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
** GNU General Public License for more details.
**
** You should have received a copy of the GNU General Public License
** along with this program; if not, write to the Free Software
** Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
** USA
**
** NeoStats CVS Identification
** $Id$
*/
/*
* query.c
* - overall query management (allocation, completion)
* - per-query memory management
* - query submission and cancellation (user-visible and internal)
*/
/*
* This file is
* Copyright (C) 1997-2000 Ian Jackson <ian@davenant.greenend.org.uk>
*
* It is part of adns, which is
* Copyright (C) 1997-2000 Ian Jackson <ian@davenant.greenend.org.uk>
* Copyright (C) 1999-2000 Tony Finch <dot@dotat.at>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include "internal.h"
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <sys/time.h>
#include "internal.h"
static adns_query query_alloc(adns_state ads, const typeinfo * typei,
adns_queryflags flags, struct timeval now)
{
/* Allocate a virgin query and return it. */
adns_query qu;
qu = malloc(sizeof(*qu));
if (!qu)
return 0;
qu->answer = malloc(sizeof(*qu->answer));
if (!qu->answer) {
free(qu);
return 0;
}
qu->ads = ads;
qu->state = query_tosend;
qu->back = qu->next = qu->parent = 0;
ALIST_INIT(qu->children);
ALINK_INIT(qu->siblings);
ALIST_INIT(qu->allocations);
qu->interim_allocd = 0;
qu->preserved_allocd = 0;
qu->final_allocspace = 0;
qu->typei = typei;
qu->query_dgram = 0;
qu->query_dglen = 0;
adns__vbuf_init(&qu->vb);
qu->cname_dgram = 0;
qu->cname_dglen = qu->cname_begin = 0;
adns__vbuf_init(&qu->search_vb);
qu->search_origlen = qu->search_pos = qu->search_doneabs = 0;
qu->id = -2; /* will be overwritten with real id before we leave adns */
qu->flags = flags;
qu->retries = 0;
qu->udpnextserver = 0;
qu->udpsent = 0;
timerclear(&qu->timeout);
qu->expires = now.tv_sec + MAXTTLBELIEVE;
memset(&qu->ctx, 0, sizeof(qu->ctx));
qu->answer->status = adns_s_ok;
qu->answer->cname = qu->answer->owner = 0;
qu->answer->type = typei->type;
qu->answer->expires = -1;
qu->answer->nrrs = 0;
qu->answer->rrs.untyped = 0;
qu->answer->rrsz = typei->rrsz;
return qu;
}
static void query_submit(adns_state ads, adns_query qu,
const typeinfo * typei, vbuf * qumsg_vb, int id,
adns_queryflags flags, struct timeval now)
{
/* Fills in the query message in for a previously-allocated query,
* and submits it. Cannot fail. Takes over the memory for qumsg_vb.
*/
qu->vb = *qumsg_vb;
adns__vbuf_init(qumsg_vb);
qu->query_dgram = malloc(qu->vb.used);
if (!qu->query_dgram) {
adns__query_fail(qu, adns_s_nomemory);
return;
}
qu->id = id;
qu->query_dglen = qu->vb.used;
memcpy(qu->query_dgram, qu->vb.buf, qu->vb.used);
adns__query_send(qu, now);
}
adns_status adns__internal_submit(adns_state ads, adns_query * query_r,
const typeinfo * typei, vbuf * qumsg_vb,
int id, adns_queryflags flags,
struct timeval now, const qcontext * ctx)
{
adns_query qu;
qu = query_alloc(ads, typei, flags, now);
if (!qu) {
adns__vbuf_free(qumsg_vb);
return adns_s_nomemory;
}
*query_r = qu;
memcpy(&qu->ctx, ctx, sizeof(qu->ctx));
query_submit(ads, qu, typei, qumsg_vb, id, flags, now);
return adns_s_ok;
}
static void query_simple(adns_state ads, adns_query qu,
const char *owner, int ol,
const typeinfo * typei, adns_queryflags flags,
struct timeval now)
{
vbuf vb_new;
int id;
adns_status stat;
stat = adns__mkquery(ads, &qu->vb, &id, owner, ol, typei, flags);
if (stat) {
if (stat == adns_s_querydomaintoolong
&& (flags & adns_qf_search)) {
adns__search_next(ads, qu, now);
return;
} else {
adns__query_fail(qu, stat);
return;
}
}
vb_new = qu->vb;
adns__vbuf_init(&qu->vb);
query_submit(ads, qu, typei, &vb_new, id, flags, now);
}
void adns__search_next(adns_state ads, adns_query qu, struct timeval now)
{
const char *nextentry;
adns_status stat;
if (qu->search_doneabs < 0) {
nextentry = 0;
qu->search_doneabs = 1;
} else {
if (qu->search_pos >= ads->nsearchlist) {
if (qu->search_doneabs) {
stat = adns_s_nxdomain;
goto x_fail;
return;
} else {
nextentry = 0;
qu->search_doneabs = 1;
}
} else {
nextentry = ads->searchlist[qu->search_pos++];
}
}
qu->search_vb.used = qu->search_origlen;
if (nextentry) {
if (!adns__vbuf_append(&qu->search_vb, ".", 1) ||
!adns__vbuf_appendstr(&qu->search_vb, nextentry)) {
stat = adns_s_nomemory;
goto x_fail;
}
}
free(qu->query_dgram);
qu->query_dgram = 0;
qu->query_dglen = 0;
query_simple(ads, qu, qu->search_vb.buf, qu->search_vb.used,
qu->typei, qu->flags, now);
return;
x_fail:
adns__query_fail(qu, stat);
}
static int save_owner(adns_query qu, const char *owner, int ol)
{
/* Returns 1 if OK, otherwise there was no memory. */
adns_answer *ans;
ans = qu->answer;
assert(!ans->owner);
ans->owner = adns__alloc_preserved(qu, ol + 1);
if (!ans->owner)
return 0;
memcpy(ans->owner, owner, ol);
ans->owner[ol] = 0;
return 1;
}
int adns_submit(adns_state ads,
const char *owner,
adns_rrtype type,
adns_queryflags flags, void *context, adns_query * query_r)
{
int r, ol, ndots;
adns_status stat;
const typeinfo *typei;
struct timeval now;
adns_query qu;
const char *p;
adns__consistency(ads, 0, cc_entex);
typei = adns__findtype(type);
if (!typei)
return ENOSYS;
r = gettimeofday(&now, 0);
if (r)
goto x_errno;
qu = query_alloc(ads, typei, flags, now);
if (!qu)
goto x_errno;
qu->ctx.ext = context;
qu->ctx.callback = 0;
memset(&qu->ctx.info, 0, sizeof(qu->ctx.info));
*query_r = qu;
ol = strlen(owner);
if (!ol) {
stat = adns_s_querydomaininvalid;
goto x_adnsfail;
}
if (ol > DNS_MAXDOMAIN + 1) {
stat = adns_s_querydomaintoolong;
goto x_adnsfail;
}
if (ol >= 1 && owner[ol - 1] == '.'
&& (ol < 2 || owner[ol - 2] != '\\')) {
flags &= ~adns_qf_search;
qu->flags = flags;
ol--;
}
if (flags & adns_qf_search) {
r = adns__vbuf_append(&qu->search_vb, owner, ol);
if (!r) {
stat = adns_s_nomemory;
goto x_adnsfail;
}
for (ndots = 0, p = owner; (p = strchr(p, '.'));
p++, ndots++);
qu->search_doneabs = (ndots >= ads->searchndots) ? -1 : 0;
qu->search_origlen = ol;
adns__search_next(ads, qu, now);
} else {
if (flags & adns_qf_owner) {
if (!save_owner(qu, owner, ol)) {
stat = adns_s_nomemory;
goto x_adnsfail;
}
}
query_simple(ads, qu, owner, ol, typei, flags, now);
}
adns__autosys(ads, now);
adns__consistency(ads, qu, cc_entex);
return 0;
x_adnsfail:
adns__query_fail(qu, stat);
adns__consistency(ads, qu, cc_entex);
return 0;
x_errno:
r = errno;
assert(r);
adns__consistency(ads, 0, cc_entex);
return r;
}
int adns_submit_reverse_any(adns_state ads,
const struct sockaddr *addr,
const char *zone,
adns_rrtype type,
adns_queryflags flags,
void *context, adns_query * query_r)
{
const unsigned char *iaddr;
char *buf, *buf_free;
char shortbuf[100];
int r, lreq;
flags &= ~adns_qf_search;
if (addr->sa_family != AF_INET)
return ENOSYS;
iaddr =
(const unsigned char *) &(((const struct sockaddr_in *) addr)->
sin_addr);
lreq = strlen(zone) + 4 * 4 + 1;
if (lreq > sizeof(shortbuf)) {
buf = malloc(strlen(zone) + 4 * 4 + 1);
if (!buf)
return errno;
buf_free = buf;
} else {
buf = shortbuf;
buf_free = 0;
}
sprintf(buf, "%d.%d.%d.%d.%s", iaddr[3], iaddr[2], iaddr[1],
iaddr[0], zone);
r = adns_submit(ads, buf, type, flags, context, query_r);
free(buf_free);
return r;
}
int adns_submit_reverse(adns_state ads,
const struct sockaddr *addr,
adns_rrtype type,
adns_queryflags flags,
void *context, adns_query * query_r)
{
if (type != adns_r_ptr && type != adns_r_ptr_raw)
return EINVAL;
return adns_submit_reverse_any(ads, addr, "in-addr.arpa", type,
flags, context, query_r);
}
int adns_synchronous(adns_state ads,
const char *owner,
adns_rrtype type,
adns_queryflags flags, adns_answer ** answer_r)
{
adns_query qu;
int r;
r = adns_submit(ads, owner, type, flags, 0, &qu);
if (r)
return r;
r = adns_wait(ads, &qu, answer_r, 0);
if (r)
adns_cancel(qu);
return r;
}
static void *alloc_common(adns_query qu, size_t sz)
{
allocnode *an;
if (!sz)
return qu; /* Any old pointer will do */
assert(!qu->final_allocspace);
an = malloc(MEM_ROUND(MEM_ROUND(sizeof(*an)) + sz));
if (!an)
return 0;
LIST_LINK_TAIL(qu->allocations, an);
return (byte *) an + MEM_ROUND(sizeof(*an));
}
void *adns__alloc_interim(adns_query qu, size_t sz)
{
void *rv;
sz = MEM_ROUND(sz);
rv = alloc_common(qu, sz);
if (!rv)
return 0;
qu->interim_allocd += sz;
return rv;
}
void *adns__alloc_preserved(adns_query qu, size_t sz)
{
void *rv;
sz = MEM_ROUND(sz);
rv = adns__alloc_interim(qu, sz);
if (!rv)
return 0;
qu->preserved_allocd += sz;
return rv;
}
void *adns__alloc_mine(adns_query qu, size_t sz)
{
return alloc_common(qu, MEM_ROUND(sz));
}
void adns__transfer_interim(adns_query from, adns_query to, void *block,
size_t sz)
{
allocnode *an;
if (!block)
return;
an = (void *) ((byte *) block - MEM_ROUND(sizeof(*an)));
assert(!to->final_allocspace);
assert(!from->final_allocspace);
LIST_UNLINK(from->allocations, an);
LIST_LINK_TAIL(to->allocations, an);
sz = MEM_ROUND(sz);
from->interim_allocd -= sz;
to->interim_allocd += sz;
if (to->expires > from->expires)
to->expires = from->expires;
}
void *adns__alloc_final(adns_query qu, size_t sz)
{
/* When we're in the _final stage, we _subtract_ from interim_alloc'd
* each allocation, and use final_allocspace to point to the next free
* bit.
*/
void *rp;
sz = MEM_ROUND(sz);
rp = qu->final_allocspace;
assert(rp);
qu->interim_allocd -= sz;
assert(qu->interim_allocd >= 0);
qu->final_allocspace = (byte *) rp + sz;
return rp;
}
static void cancel_children(adns_query qu)
{
adns_query cqu, ncqu;
for (cqu = qu->children.head; cqu; cqu = ncqu) {
ncqu = cqu->siblings.next;
adns_cancel(cqu);
}
}
void adns__reset_preserved(adns_query qu)
{
assert(!qu->final_allocspace);
cancel_children(qu);
qu->answer->nrrs = 0;
qu->answer->rrs.untyped = 0;
qu->interim_allocd = qu->preserved_allocd;
}
static void free_query_allocs(adns_query qu)
{
allocnode *an, *ann;
cancel_children(qu);
for (an = qu->allocations.head; an; an = ann) {
ann = an->next;
free(an);
}
ALIST_INIT(qu->allocations);
adns__vbuf_free(&qu->vb);
adns__vbuf_free(&qu->search_vb);
free(qu->query_dgram);
qu->query_dgram = 0;
}
void adns_cancel(adns_query qu)
{
adns_state ads;
ads = qu->ads;
adns__consistency(ads, qu, cc_entex);
if (qu->parent)
LIST_UNLINK_PART(qu->parent->children, qu, siblings.);
switch (qu->state) {
case query_tosend:
LIST_UNLINK(ads->udpw, qu);
break;
case query_tcpw:
LIST_UNLINK(ads->tcpw, qu);
break;
case query_childw:
LIST_UNLINK(ads->childw, qu);
break;
case query_done:
LIST_UNLINK(ads->output, qu);
break;
default:
abort();
}
free_query_allocs(qu);
free(qu->answer);
free(qu);
adns__consistency(ads, 0, cc_entex);
}
void adns__update_expires(adns_query qu, unsigned long ttl,
struct timeval now)
{
time_t max;
assert(ttl <= MAXTTLBELIEVE);
max = now.tv_sec + ttl;
if (qu->expires < max)
return;
qu->expires = max;
}
static void makefinal_query(adns_query qu)
{
adns_answer *ans;
int rrn;
ans = qu->answer;
if (qu->interim_allocd) {
ans =
realloc(qu->answer,
MEM_ROUND(MEM_ROUND(sizeof(*ans)) +
qu->interim_allocd));
if (!ans)
goto x_nomem;
qu->answer = ans;
}
qu->final_allocspace = (byte *) ans + MEM_ROUND(sizeof(*ans));
adns__makefinal_str(qu, &ans->cname);
adns__makefinal_str(qu, &ans->owner);
if (ans->nrrs) {
adns__makefinal_block(qu, &ans->rrs.untyped,
ans->nrrs * ans->rrsz);
for (rrn = 0; rrn < ans->nrrs; rrn++)
qu->typei->makefinal(qu,
ans->rrs.bytes +
rrn * ans->rrsz);
}
free_query_allocs(qu);
return;
x_nomem:
qu->preserved_allocd = 0;
qu->answer->cname = 0;
qu->answer->owner = 0;
adns__reset_preserved(qu); /* (but we just threw away the preserved stuff) */
qu->answer->status = adns_s_nomemory;
free_query_allocs(qu);
}
void adns__query_done(adns_query qu)
{
adns_answer *ans;
adns_query parent;
cancel_children(qu);
qu->id = -1;
ans = qu->answer;
if (qu->flags & adns_qf_owner && qu->flags & adns_qf_search &&
ans->status != adns_s_nomemory) {
if (!save_owner(qu, qu->search_vb.buf, qu->search_vb.used)) {
adns__query_fail(qu, adns_s_nomemory);
return;
}
}
if (ans->nrrs && qu->typei->diff_needswap) {
if (!adns__vbuf_ensure(&qu->vb, qu->typei->rrsz)) {
adns__query_fail(qu, adns_s_nomemory);
return;
}
adns__isort(ans->rrs.bytes, ans->nrrs, ans->rrsz,
qu->vb.buf,
(int (*)(void *, const void *, const void *))
qu->typei->diff_needswap, qu->ads);
}
ans->expires = qu->expires;
parent = qu->parent;
if (parent) {
LIST_UNLINK_PART(parent->children, qu, siblings.);
LIST_UNLINK(qu->ads->childw, parent);
qu->ctx.callback(parent, qu);
free_query_allocs(qu);
free(qu->answer);
free(qu);
} else {
makefinal_query(qu);
LIST_LINK_TAIL(qu->ads->output, qu);
qu->state = query_done;
}
}
void adns__query_fail(adns_query qu, adns_status stat)
{
adns__reset_preserved(qu);
qu->answer->status = stat;
adns__query_done(qu);
}
void adns__makefinal_str(adns_query qu, char **strp)
{
int l;
char *before, *after;
before = *strp;
if (!before)
return;
l = strlen(before) + 1;
after = adns__alloc_final(qu, l);
memcpy(after, before, l);
*strp = after;
}
void adns__makefinal_block(adns_query qu, void **blpp, size_t sz)
{
void *before, *after;
before = *blpp;
if (!before)
return;
after = adns__alloc_final(qu, sz);
memcpy(after, before, sz);
*blpp = after;
}