freebsd-dev/contrib/bind9/lib/dns/request.c
2004-09-19 01:30:24 +00:00

1456 lines
39 KiB
C

/*
* Copyright (C) 2004 Internet Systems Consortium, Inc. ("ISC")
* Copyright (C) 2000-2002 Internet Software Consortium.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
* INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
* LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
* OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
* PERFORMANCE OF THIS SOFTWARE.
*/
/* $Id: request.c,v 1.64.2.1.10.6 2004/03/08 09:04:31 marka Exp $ */
#include <config.h>
#include <isc/magic.h>
#include <isc/mem.h>
#include <isc/task.h>
#include <isc/timer.h>
#include <isc/util.h>
#include <dns/acl.h>
#include <dns/compress.h>
#include <dns/dispatch.h>
#include <dns/events.h>
#include <dns/log.h>
#include <dns/message.h>
#include <dns/rdata.h>
#include <dns/rdatastruct.h>
#include <dns/request.h>
#include <dns/result.h>
#include <dns/tsig.h>
#define REQUESTMGR_MAGIC ISC_MAGIC('R', 'q', 'u', 'M')
#define VALID_REQUESTMGR(mgr) ISC_MAGIC_VALID(mgr, REQUESTMGR_MAGIC)
#define REQUEST_MAGIC ISC_MAGIC('R', 'q', 'u', '!')
#define VALID_REQUEST(request) ISC_MAGIC_VALID(request, REQUEST_MAGIC)
typedef ISC_LIST(dns_request_t) dns_requestlist_t;
#define DNS_REQUEST_NLOCKS 7
struct dns_requestmgr {
unsigned int magic;
isc_mutex_t lock;
isc_mem_t *mctx;
/* locked */
isc_int32_t eref;
isc_int32_t iref;
isc_timermgr_t *timermgr;
isc_socketmgr_t *socketmgr;
isc_taskmgr_t *taskmgr;
dns_dispatchmgr_t *dispatchmgr;
dns_dispatch_t *dispatchv4;
dns_dispatch_t *dispatchv6;
isc_boolean_t exiting;
isc_eventlist_t whenshutdown;
unsigned int hash;
isc_mutex_t locks[DNS_REQUEST_NLOCKS];
dns_requestlist_t requests;
};
struct dns_request {
unsigned int magic;
unsigned int hash;
isc_mem_t *mctx;
isc_int32_t flags;
ISC_LINK(dns_request_t) link;
isc_buffer_t *query;
isc_buffer_t *answer;
dns_requestevent_t *event;
dns_dispatch_t *dispatch;
dns_dispentry_t *dispentry;
isc_timer_t *timer;
dns_requestmgr_t *requestmgr;
isc_buffer_t *tsig;
dns_tsigkey_t *tsigkey;
isc_event_t ctlevent;
isc_boolean_t canceling; /* ctlevent outstanding */
isc_sockaddr_t destaddr;
unsigned int udpcount;
};
#define DNS_REQUEST_F_CONNECTING 0x0001
#define DNS_REQUEST_F_SENDING 0x0002
#define DNS_REQUEST_F_CANCELED 0x0004 /* ctlevent received, or otherwise
synchronously canceled */
#define DNS_REQUEST_F_TIMEDOUT 0x0008 /* cancelled due to a timeout */
#define DNS_REQUEST_F_TCP 0x0010 /* This request used TCP */
#define DNS_REQUEST_CANCELED(r) \
(((r)->flags & DNS_REQUEST_F_CANCELED) != 0)
#define DNS_REQUEST_CONNECTING(r) \
(((r)->flags & DNS_REQUEST_F_CONNECTING) != 0)
#define DNS_REQUEST_SENDING(r) \
(((r)->flags & DNS_REQUEST_F_SENDING) != 0)
#define DNS_REQUEST_TIMEDOUT(r) \
(((r)->flags & DNS_REQUEST_F_TIMEDOUT) != 0)
/***
*** Forward
***/
static void mgr_destroy(dns_requestmgr_t *requestmgr);
static void mgr_shutdown(dns_requestmgr_t *requestmgr);
static unsigned int mgr_gethash(dns_requestmgr_t *requestmgr);
static void send_shutdown_events(dns_requestmgr_t *requestmgr);
static isc_result_t req_render(dns_message_t *message, isc_buffer_t **buffer,
unsigned int options, isc_mem_t *mctx);
static void req_senddone(isc_task_t *task, isc_event_t *event);
static void req_response(isc_task_t *task, isc_event_t *event);
static void req_timeout(isc_task_t *task, isc_event_t *event);
static void req_connected(isc_task_t *task, isc_event_t *event);
static void req_sendevent(dns_request_t *request, isc_result_t result);
static void req_cancel(dns_request_t *request);
static void req_destroy(dns_request_t *request);
static void req_log(int level, const char *fmt, ...) ISC_FORMAT_PRINTF(2, 3);
static void do_cancel(isc_task_t *task, isc_event_t *event);
/***
*** Public
***/
isc_result_t
dns_requestmgr_create(isc_mem_t *mctx,
isc_timermgr_t *timermgr,
isc_socketmgr_t *socketmgr,
isc_taskmgr_t *taskmgr,
dns_dispatchmgr_t *dispatchmgr,
dns_dispatch_t *dispatchv4,
dns_dispatch_t *dispatchv6,
dns_requestmgr_t **requestmgrp)
{
dns_requestmgr_t *requestmgr;
isc_socket_t *socket;
isc_result_t result;
int i;
req_log(ISC_LOG_DEBUG(3), "dns_requestmgr_create");
REQUIRE(requestmgrp != NULL && *requestmgrp == NULL);
REQUIRE(timermgr != NULL);
REQUIRE(socketmgr != NULL);
REQUIRE(taskmgr != NULL);
REQUIRE(dispatchmgr != NULL);
if (dispatchv4 != NULL) {
socket = dns_dispatch_getsocket(dispatchv4);
REQUIRE(isc_socket_gettype(socket) == isc_sockettype_udp);
}
if (dispatchv6 != NULL) {
socket = dns_dispatch_getsocket(dispatchv6);
REQUIRE(isc_socket_gettype(socket) == isc_sockettype_udp);
}
requestmgr = isc_mem_get(mctx, sizeof(*requestmgr));
if (requestmgr == NULL)
return (ISC_R_NOMEMORY);
result = isc_mutex_init(&requestmgr->lock);
if (result != ISC_R_SUCCESS) {
isc_mem_put(mctx, requestmgr, sizeof(*requestmgr));
return (result);
}
for (i = 0; i < DNS_REQUEST_NLOCKS; i++) {
result = isc_mutex_init(&requestmgr->locks[i]);
if (result != ISC_R_SUCCESS) {
while (--i >= 0)
DESTROYLOCK(&requestmgr->locks[i]);
DESTROYLOCK(&requestmgr->lock);
isc_mem_put(mctx, requestmgr, sizeof(*requestmgr));
return (result);
}
}
requestmgr->timermgr = timermgr;
requestmgr->socketmgr = socketmgr;
requestmgr->taskmgr = taskmgr;
requestmgr->dispatchmgr = dispatchmgr;
requestmgr->dispatchv4 = NULL;
if (dispatchv4 != NULL)
dns_dispatch_attach(dispatchv4, &requestmgr->dispatchv4);
requestmgr->dispatchv6 = NULL;
if (dispatchv6 != NULL)
dns_dispatch_attach(dispatchv6, &requestmgr->dispatchv6);
requestmgr->mctx = NULL;
isc_mem_attach(mctx, &requestmgr->mctx);
requestmgr->eref = 1; /* implict attach */
requestmgr->iref = 0;
ISC_LIST_INIT(requestmgr->whenshutdown);
ISC_LIST_INIT(requestmgr->requests);
requestmgr->exiting = ISC_FALSE;
requestmgr->hash = 0;
requestmgr->magic = REQUESTMGR_MAGIC;
req_log(ISC_LOG_DEBUG(3), "dns_requestmgr_create: %p", requestmgr);
*requestmgrp = requestmgr;
return (ISC_R_SUCCESS);
}
void
dns_requestmgr_whenshutdown(dns_requestmgr_t *requestmgr, isc_task_t *task,
isc_event_t **eventp)
{
isc_task_t *clone;
isc_event_t *event;
req_log(ISC_LOG_DEBUG(3), "dns_requestmgr_whenshutdown");
REQUIRE(VALID_REQUESTMGR(requestmgr));
REQUIRE(eventp != NULL);
event = *eventp;
*eventp = NULL;
LOCK(&requestmgr->lock);
if (requestmgr->exiting) {
/*
* We're already shutdown. Send the event.
*/
event->ev_sender = requestmgr;
isc_task_send(task, &event);
} else {
clone = NULL;
isc_task_attach(task, &clone);
event->ev_sender = clone;
ISC_LIST_APPEND(requestmgr->whenshutdown, event, ev_link);
}
UNLOCK(&requestmgr->lock);
}
void
dns_requestmgr_shutdown(dns_requestmgr_t *requestmgr) {
REQUIRE(VALID_REQUESTMGR(requestmgr));
req_log(ISC_LOG_DEBUG(3), "dns_requestmgr_shutdown: %p", requestmgr);
LOCK(&requestmgr->lock);
mgr_shutdown(requestmgr);
UNLOCK(&requestmgr->lock);
}
static void
mgr_shutdown(dns_requestmgr_t *requestmgr) {
dns_request_t *request;
/*
* Caller holds lock.
*/
if (!requestmgr->exiting) {
requestmgr->exiting = ISC_TRUE;
for (request = ISC_LIST_HEAD(requestmgr->requests);
request != NULL;
request = ISC_LIST_NEXT(request, link)) {
dns_request_cancel(request);
}
if (requestmgr->iref == 0) {
INSIST(ISC_LIST_EMPTY(requestmgr->requests));
send_shutdown_events(requestmgr);
}
}
}
static void
requestmgr_attach(dns_requestmgr_t *source, dns_requestmgr_t **targetp) {
/*
* Locked by caller.
*/
REQUIRE(VALID_REQUESTMGR(source));
REQUIRE(targetp != NULL && *targetp == NULL);
REQUIRE(!source->exiting);
source->iref++;
*targetp = source;
req_log(ISC_LOG_DEBUG(3), "requestmgr_attach: %p: eref %d iref %d",
source, source->eref, source->iref);
}
static void
requestmgr_detach(dns_requestmgr_t **requestmgrp) {
dns_requestmgr_t *requestmgr;
isc_boolean_t need_destroy = ISC_FALSE;
REQUIRE(requestmgrp != NULL);
requestmgr = *requestmgrp;
REQUIRE(VALID_REQUESTMGR(requestmgr));
*requestmgrp = NULL;
LOCK(&requestmgr->lock);
INSIST(requestmgr->iref > 0);
requestmgr->iref--;
req_log(ISC_LOG_DEBUG(3), "requestmgr_detach: %p: eref %d iref %d",
requestmgr, requestmgr->eref, requestmgr->iref);
if (requestmgr->iref == 0 && requestmgr->exiting) {
INSIST(ISC_LIST_HEAD(requestmgr->requests) == NULL);
send_shutdown_events(requestmgr);
if (requestmgr->eref == 0)
need_destroy = ISC_TRUE;
}
UNLOCK(&requestmgr->lock);
if (need_destroy)
mgr_destroy(requestmgr);
}
void
dns_requestmgr_attach(dns_requestmgr_t *source, dns_requestmgr_t **targetp) {
REQUIRE(VALID_REQUESTMGR(source));
REQUIRE(targetp != NULL && *targetp == NULL);
REQUIRE(!source->exiting);
LOCK(&source->lock);
source->eref++;
*targetp = source;
UNLOCK(&source->lock);
req_log(ISC_LOG_DEBUG(3), "dns_requestmgr_attach: %p: eref %d iref %d",
source, source->eref, source->iref);
}
void
dns_requestmgr_detach(dns_requestmgr_t **requestmgrp) {
dns_requestmgr_t *requestmgr;
isc_boolean_t need_destroy = ISC_FALSE;
REQUIRE(requestmgrp != NULL);
requestmgr = *requestmgrp;
REQUIRE(VALID_REQUESTMGR(requestmgr));
LOCK(&requestmgr->lock);
INSIST(requestmgr->eref > 0);
requestmgr->eref--;
req_log(ISC_LOG_DEBUG(3), "dns_requestmgr_detach: %p: eref %d iref %d",
requestmgr, requestmgr->eref, requestmgr->iref);
if (requestmgr->eref == 0 && requestmgr->iref == 0) {
INSIST(requestmgr->exiting &&
ISC_LIST_HEAD(requestmgr->requests) == NULL);
need_destroy = ISC_TRUE;
}
UNLOCK(&requestmgr->lock);
if (need_destroy)
mgr_destroy(requestmgr);
*requestmgrp = NULL;
}
static void
send_shutdown_events(dns_requestmgr_t *requestmgr) {
isc_event_t *event, *next_event;
isc_task_t *etask;
req_log(ISC_LOG_DEBUG(3), "send_shutdown_events: %p", requestmgr);
/*
* Caller must be holding the manager lock.
*/
for (event = ISC_LIST_HEAD(requestmgr->whenshutdown);
event != NULL;
event = next_event) {
next_event = ISC_LIST_NEXT(event, ev_link);
ISC_LIST_UNLINK(requestmgr->whenshutdown, event, ev_link);
etask = event->ev_sender;
event->ev_sender = requestmgr;
isc_task_sendanddetach(&etask, &event);
}
}
static void
mgr_destroy(dns_requestmgr_t *requestmgr) {
int i;
isc_mem_t *mctx;
req_log(ISC_LOG_DEBUG(3), "mgr_destroy");
REQUIRE(requestmgr->eref == 0);
REQUIRE(requestmgr->iref == 0);
DESTROYLOCK(&requestmgr->lock);
for (i = 0; i < DNS_REQUEST_NLOCKS; i++)
DESTROYLOCK(&requestmgr->locks[i]);
if (requestmgr->dispatchv4 != NULL)
dns_dispatch_detach(&requestmgr->dispatchv4);
if (requestmgr->dispatchv6 != NULL)
dns_dispatch_detach(&requestmgr->dispatchv6);
requestmgr->magic = 0;
mctx = requestmgr->mctx;
isc_mem_put(mctx, requestmgr, sizeof(*requestmgr));
isc_mem_detach(&mctx);
}
static unsigned int
mgr_gethash(dns_requestmgr_t *requestmgr) {
req_log(ISC_LOG_DEBUG(3), "mgr_gethash");
/*
* Locked by caller.
*/
requestmgr->hash++;
return (requestmgr->hash % DNS_REQUEST_NLOCKS);
}
static inline isc_result_t
req_send(dns_request_t *request, isc_task_t *task, isc_sockaddr_t *address) {
isc_region_t r;
isc_socket_t *socket;
isc_result_t result;
req_log(ISC_LOG_DEBUG(3), "req_send: request %p", request);
REQUIRE(VALID_REQUEST(request));
socket = dns_dispatch_getsocket(request->dispatch);
isc_buffer_usedregion(request->query, &r);
result = isc_socket_sendto(socket, &r, task, req_senddone,
request, address, NULL);
if (result == ISC_R_SUCCESS)
request->flags |= DNS_REQUEST_F_SENDING;
return (result);
}
static isc_result_t
new_request(isc_mem_t *mctx, dns_request_t **requestp) {
dns_request_t *request;
request = isc_mem_get(mctx, sizeof(*request));
if (request == NULL)
return (ISC_R_NOMEMORY);
/*
* Zero structure.
*/
request->magic = 0;
request->mctx = NULL;
request->flags = 0;
ISC_LINK_INIT(request, link);
request->query = NULL;
request->answer = NULL;
request->event = NULL;
request->dispatch = NULL;
request->dispentry = NULL;
request->timer = NULL;
request->requestmgr = NULL;
request->tsig = NULL;
request->tsigkey = NULL;
ISC_EVENT_INIT(&request->ctlevent, sizeof(request->ctlevent), 0, NULL,
DNS_EVENT_REQUESTCONTROL, do_cancel, request, NULL,
NULL, NULL);
request->canceling = ISC_FALSE;
request->udpcount = 0;
isc_mem_attach(mctx, &request->mctx);
request->magic = REQUEST_MAGIC;
*requestp = request;
return (ISC_R_SUCCESS);
}
static isc_boolean_t
isblackholed(dns_dispatchmgr_t *dispatchmgr, isc_sockaddr_t *destaddr) {
dns_acl_t *blackhole;
isc_netaddr_t netaddr;
int match;
isc_boolean_t drop = ISC_FALSE;
char netaddrstr[ISC_NETADDR_FORMATSIZE];
blackhole = dns_dispatchmgr_getblackhole(dispatchmgr);
if (blackhole != NULL) {
isc_netaddr_fromsockaddr(&netaddr, destaddr);
if (dns_acl_match(&netaddr, NULL, blackhole,
NULL, &match, NULL) == ISC_R_SUCCESS &&
match > 0)
drop = ISC_TRUE;
}
if (drop) {
isc_netaddr_format(&netaddr, netaddrstr, sizeof(netaddrstr));
req_log(ISC_LOG_DEBUG(10), "blackholed address %s", netaddrstr);
}
return (drop);
}
static isc_result_t
create_tcp_dispatch(dns_requestmgr_t *requestmgr, isc_sockaddr_t *srcaddr,
isc_sockaddr_t *destaddr, dns_dispatch_t **dispatchp)
{
isc_result_t result;
isc_socket_t *socket = NULL;
isc_sockaddr_t src;
unsigned int attrs;
isc_sockaddr_t bind_any;
result = isc_socket_create(requestmgr->socketmgr,
isc_sockaddr_pf(destaddr),
isc_sockettype_tcp, &socket);
if (result != ISC_R_SUCCESS)
return (result);
if (srcaddr == NULL) {
isc_sockaddr_anyofpf(&bind_any,
isc_sockaddr_pf(destaddr));
result = isc_socket_bind(socket, &bind_any);
} else {
src = *srcaddr;
isc_sockaddr_setport(&src, 0);
result = isc_socket_bind(socket, &src);
}
if (result != ISC_R_SUCCESS)
goto cleanup;
attrs = 0;
attrs |= DNS_DISPATCHATTR_TCP;
attrs |= DNS_DISPATCHATTR_PRIVATE;
if (isc_sockaddr_pf(destaddr) == AF_INET)
attrs |= DNS_DISPATCHATTR_IPV4;
else
attrs |= DNS_DISPATCHATTR_IPV6;
attrs |= DNS_DISPATCHATTR_MAKEQUERY;
result = dns_dispatch_createtcp(requestmgr->dispatchmgr,
socket, requestmgr->taskmgr,
4096, 2, 1, 1, 3, attrs,
dispatchp);
cleanup:
isc_socket_detach(&socket);
return (result);
}
static isc_result_t
find_udp_dispatch(dns_requestmgr_t *requestmgr, isc_sockaddr_t *srcaddr,
isc_sockaddr_t *destaddr, dns_dispatch_t **dispatchp)
{
dns_dispatch_t *disp = NULL;
unsigned int attrs, attrmask;
if (srcaddr == NULL) {
switch (isc_sockaddr_pf(destaddr)) {
case PF_INET:
disp = requestmgr->dispatchv4;
break;
case PF_INET6:
disp = requestmgr->dispatchv6;
break;
default:
return (ISC_R_NOTIMPLEMENTED);
}
if (disp == NULL)
return (ISC_R_FAMILYNOSUPPORT);
dns_dispatch_attach(disp, dispatchp);
return (ISC_R_SUCCESS);
}
attrs = 0;
attrs |= DNS_DISPATCHATTR_UDP;
switch (isc_sockaddr_pf(srcaddr)) {
case PF_INET:
attrs |= DNS_DISPATCHATTR_IPV4;
break;
case PF_INET6:
attrs |= DNS_DISPATCHATTR_IPV6;
break;
default:
return (ISC_R_NOTIMPLEMENTED);
}
attrmask = 0;
attrmask |= DNS_DISPATCHATTR_UDP;
attrmask |= DNS_DISPATCHATTR_TCP;
attrmask |= DNS_DISPATCHATTR_IPV4;
attrmask |= DNS_DISPATCHATTR_IPV6;
return (dns_dispatch_getudp(requestmgr->dispatchmgr,
requestmgr->socketmgr,
requestmgr->taskmgr,
srcaddr, 4096,
1000, 32768, 16411, 16433,
attrs, attrmask,
dispatchp));
}
static isc_result_t
get_dispatch(isc_boolean_t tcp, dns_requestmgr_t *requestmgr,
isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
dns_dispatch_t **dispatchp)
{
isc_result_t result;
if (tcp)
result = create_tcp_dispatch(requestmgr, srcaddr,
destaddr, dispatchp);
else
result = find_udp_dispatch(requestmgr, srcaddr,
destaddr, dispatchp);
return (result);
}
static isc_result_t
set_timer(isc_timer_t *timer, unsigned int timeout, unsigned int udpresend) {
isc_time_t expires;
isc_interval_t interval;
isc_result_t result;
isc_timertype_t timertype;
isc_interval_set(&interval, timeout, 0);
result = isc_time_nowplusinterval(&expires, &interval);
isc_interval_set(&interval, udpresend, 0);
timertype = udpresend != 0 ? isc_timertype_limited : isc_timertype_once;
if (result == ISC_R_SUCCESS)
result = isc_timer_reset(timer, timertype, &expires,
&interval, ISC_FALSE);
return (result);
}
isc_result_t
dns_request_createraw(dns_requestmgr_t *requestmgr, isc_buffer_t *msgbuf,
isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
unsigned int options, unsigned int timeout,
isc_task_t *task, isc_taskaction_t action, void *arg,
dns_request_t **requestp)
{
return(dns_request_createraw3(requestmgr, msgbuf, srcaddr, destaddr,
options, timeout, 0, 0, task, action,
arg, requestp));
}
isc_result_t
dns_request_createraw2(dns_requestmgr_t *requestmgr, isc_buffer_t *msgbuf,
isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
unsigned int options, unsigned int timeout,
unsigned int udptimeout, isc_task_t *task,
isc_taskaction_t action, void *arg,
dns_request_t **requestp)
{
unsigned int udpretries = 0;
if (udptimeout != 0)
udpretries = timeout / udptimeout;
return (dns_request_createraw3(requestmgr, msgbuf, srcaddr, destaddr,
options, timeout, udptimeout,
udpretries, task, action, arg,
requestp));
}
isc_result_t
dns_request_createraw3(dns_requestmgr_t *requestmgr, isc_buffer_t *msgbuf,
isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
unsigned int options, unsigned int timeout,
unsigned int udptimeout, unsigned int udpretries,
isc_task_t *task, isc_taskaction_t action, void *arg,
dns_request_t **requestp)
{
dns_request_t *request = NULL;
isc_task_t *tclone = NULL;
isc_socket_t *socket = NULL;
isc_result_t result;
isc_mem_t *mctx;
dns_messageid_t id;
isc_boolean_t tcp = ISC_FALSE;
isc_region_t r;
REQUIRE(VALID_REQUESTMGR(requestmgr));
REQUIRE(msgbuf != NULL);
REQUIRE(destaddr != NULL);
REQUIRE(task != NULL);
REQUIRE(action != NULL);
REQUIRE(requestp != NULL && *requestp == NULL);
REQUIRE(timeout > 0);
if (srcaddr != NULL)
REQUIRE(isc_sockaddr_pf(srcaddr) == isc_sockaddr_pf(destaddr));
mctx = requestmgr->mctx;
req_log(ISC_LOG_DEBUG(3), "dns_request_createraw");
if (isblackholed(requestmgr->dispatchmgr, destaddr))
return (DNS_R_BLACKHOLED);
request = NULL;
result = new_request(mctx, &request);
if (result != ISC_R_SUCCESS)
return (result);
if (udptimeout == 0 && udpretries != 0) {
udptimeout = timeout / (udpretries + 1);
if (udptimeout == 0)
udptimeout = 1;
}
/*
* Create timer now. We will set it below once.
*/
result = isc_timer_create(requestmgr->timermgr, isc_timertype_inactive,
NULL, NULL, task, req_timeout, request,
&request->timer);
if (result != ISC_R_SUCCESS)
goto cleanup;
request->event = (dns_requestevent_t *)
isc_event_allocate(mctx, task, DNS_EVENT_REQUESTDONE,
action, arg, sizeof(dns_requestevent_t));
if (request->event == NULL) {
result = ISC_R_NOMEMORY;
goto cleanup;
}
isc_task_attach(task, &tclone);
request->event->ev_sender = task;
request->event->request = request;
request->event->result = ISC_R_FAILURE;
isc_buffer_usedregion(msgbuf, &r);
if (r.length < DNS_MESSAGE_HEADERLEN || r.length > 65535) {
result = DNS_R_FORMERR;
goto cleanup;
}
if ((options & DNS_REQUESTOPT_TCP) != 0 || r.length > 512)
tcp = ISC_TRUE;
result = get_dispatch(tcp, requestmgr, srcaddr, destaddr,
&request->dispatch);
if (result != ISC_R_SUCCESS)
goto cleanup;
socket = dns_dispatch_getsocket(request->dispatch);
INSIST(socket != NULL);
result = dns_dispatch_addresponse(request->dispatch, destaddr, task,
req_response, request, &id,
&request->dispentry);
if (result != ISC_R_SUCCESS)
goto cleanup;
result = isc_buffer_allocate(mctx, &request->query,
r.length + (tcp ? 2 : 0));
if (result != ISC_R_SUCCESS)
goto cleanup;
if (tcp)
isc_buffer_putuint16(request->query, (isc_uint16_t)r.length);
result = isc_buffer_copyregion(request->query, &r);
if (result != ISC_R_SUCCESS)
goto cleanup;
/* Add message ID. */
isc_buffer_usedregion(request->query, &r);
if (tcp)
isc_region_consume(&r, 2);
r.base[0] = (id>>8) & 0xff;
r.base[1] = id & 0xff;
LOCK(&requestmgr->lock);
if (requestmgr->exiting) {
UNLOCK(&requestmgr->lock);
result = ISC_R_SHUTTINGDOWN;
goto cleanup;
}
requestmgr_attach(requestmgr, &request->requestmgr);
request->hash = mgr_gethash(requestmgr);
ISC_LIST_APPEND(requestmgr->requests, request, link);
UNLOCK(&requestmgr->lock);
result = set_timer(request->timer, timeout, tcp ? 0 : udptimeout);
if (result != ISC_R_SUCCESS)
goto unlink;
request->destaddr = *destaddr;
if (tcp) {
result = isc_socket_connect(socket, destaddr, task,
req_connected, request);
if (result != ISC_R_SUCCESS)
goto unlink;
request->flags |= DNS_REQUEST_F_CONNECTING|DNS_REQUEST_F_TCP;
} else {
result = req_send(request, task, destaddr);
if (result != ISC_R_SUCCESS)
goto unlink;
}
req_log(ISC_LOG_DEBUG(3), "dns_request_createraw: request %p",
request);
*requestp = request;
return (ISC_R_SUCCESS);
unlink:
LOCK(&requestmgr->lock);
ISC_LIST_UNLINK(requestmgr->requests, request, link);
UNLOCK(&requestmgr->lock);
cleanup:
if (tclone != NULL)
isc_task_detach(&tclone);
req_destroy(request);
req_log(ISC_LOG_DEBUG(3), "dns_request_createraw: failed %s",
dns_result_totext(result));
return (result);
}
isc_result_t
dns_request_create(dns_requestmgr_t *requestmgr, dns_message_t *message,
isc_sockaddr_t *address, unsigned int options,
dns_tsigkey_t *key,
unsigned int timeout, isc_task_t *task,
isc_taskaction_t action, void *arg,
dns_request_t **requestp)
{
return (dns_request_createvia3(requestmgr, message, NULL, address,
options, key, timeout, 0, 0, task,
action, arg, requestp));
}
isc_result_t
dns_request_createvia(dns_requestmgr_t *requestmgr, dns_message_t *message,
isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
unsigned int options, dns_tsigkey_t *key,
unsigned int timeout, isc_task_t *task,
isc_taskaction_t action, void *arg,
dns_request_t **requestp)
{
return(dns_request_createvia3(requestmgr, message, srcaddr, destaddr,
options, key, timeout, 0, 0, task,
action, arg, requestp));
}
isc_result_t
dns_request_createvia2(dns_requestmgr_t *requestmgr, dns_message_t *message,
isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
unsigned int options, dns_tsigkey_t *key,
unsigned int timeout, unsigned int udptimeout,
isc_task_t *task, isc_taskaction_t action, void *arg,
dns_request_t **requestp)
{
unsigned int udpretries = 0;
if (udptimeout != 0)
udpretries = timeout / udptimeout;
return (dns_request_createvia3(requestmgr, message, srcaddr, destaddr,
options, key, timeout, udptimeout,
udpretries, task, action, arg,
requestp));
}
isc_result_t
dns_request_createvia3(dns_requestmgr_t *requestmgr, dns_message_t *message,
isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
unsigned int options, dns_tsigkey_t *key,
unsigned int timeout, unsigned int udptimeout,
unsigned int udpretries, isc_task_t *task,
isc_taskaction_t action, void *arg,
dns_request_t **requestp)
{
dns_request_t *request = NULL;
isc_task_t *tclone = NULL;
isc_socket_t *socket = NULL;
isc_result_t result;
isc_mem_t *mctx;
dns_messageid_t id;
isc_boolean_t tcp;
isc_boolean_t setkey = ISC_TRUE;
REQUIRE(VALID_REQUESTMGR(requestmgr));
REQUIRE(message != NULL);
REQUIRE(destaddr != NULL);
REQUIRE(task != NULL);
REQUIRE(action != NULL);
REQUIRE(requestp != NULL && *requestp == NULL);
REQUIRE(timeout > 0);
if (srcaddr != NULL)
REQUIRE(isc_sockaddr_pf(srcaddr) == isc_sockaddr_pf(destaddr));
mctx = requestmgr->mctx;
req_log(ISC_LOG_DEBUG(3), "dns_request_createvia");
if (isblackholed(requestmgr->dispatchmgr, destaddr))
return (DNS_R_BLACKHOLED);
request = NULL;
result = new_request(mctx, &request);
if (result != ISC_R_SUCCESS)
return (result);
if (udptimeout == 0 && udpretries != 0) {
udptimeout = timeout / (udpretries + 1);
if (udptimeout == 0)
udptimeout = 1;
}
/*
* Create timer now. We will set it below once.
*/
result = isc_timer_create(requestmgr->timermgr, isc_timertype_inactive,
NULL, NULL, task, req_timeout, request,
&request->timer);
if (result != ISC_R_SUCCESS)
goto cleanup;
request->event = (dns_requestevent_t *)
isc_event_allocate(mctx, task, DNS_EVENT_REQUESTDONE,
action, arg, sizeof(dns_requestevent_t));
if (request->event == NULL) {
result = ISC_R_NOMEMORY;
goto cleanup;
}
isc_task_attach(task, &tclone);
request->event->ev_sender = task;
request->event->request = request;
request->event->result = ISC_R_FAILURE;
if (key != NULL)
dns_tsigkey_attach(key, &request->tsigkey);
use_tcp:
tcp = ISC_TF((options & DNS_REQUESTOPT_TCP) != 0);
result = get_dispatch(tcp, requestmgr, srcaddr, destaddr,
&request->dispatch);
if (result != ISC_R_SUCCESS)
goto cleanup;
socket = dns_dispatch_getsocket(request->dispatch);
INSIST(socket != NULL);
result = dns_dispatch_addresponse(request->dispatch, destaddr, task,
req_response, request, &id,
&request->dispentry);
if (result != ISC_R_SUCCESS)
goto cleanup;
message->id = id;
if (setkey) {
result = dns_message_settsigkey(message, request->tsigkey);
if (result != ISC_R_SUCCESS)
goto cleanup;
}
result = req_render(message, &request->query, options, mctx);
if (result == DNS_R_USETCP &&
(options & DNS_REQUESTOPT_TCP) == 0) {
/*
* Try again using TCP.
*/
dns_message_renderreset(message);
dns_dispatch_removeresponse(&request->dispentry, NULL);
dns_dispatch_detach(&request->dispatch);
socket = NULL;
options |= DNS_REQUESTOPT_TCP;
setkey = ISC_FALSE;
goto use_tcp;
}
if (result != ISC_R_SUCCESS)
goto cleanup;
result = dns_message_getquerytsig(message, mctx, &request->tsig);
if (result != ISC_R_SUCCESS)
goto cleanup;
LOCK(&requestmgr->lock);
if (requestmgr->exiting) {
UNLOCK(&requestmgr->lock);
result = ISC_R_SHUTTINGDOWN;
goto cleanup;
}
requestmgr_attach(requestmgr, &request->requestmgr);
request->hash = mgr_gethash(requestmgr);
ISC_LIST_APPEND(requestmgr->requests, request, link);
UNLOCK(&requestmgr->lock);
result = set_timer(request->timer, timeout, tcp ? 0 : udptimeout);
if (result != ISC_R_SUCCESS)
goto unlink;
request->destaddr = *destaddr;
if (tcp) {
result = isc_socket_connect(socket, destaddr, task,
req_connected, request);
if (result != ISC_R_SUCCESS)
goto unlink;
request->flags |= DNS_REQUEST_F_CONNECTING|DNS_REQUEST_F_TCP;
} else {
result = req_send(request, task, destaddr);
if (result != ISC_R_SUCCESS)
goto unlink;
}
req_log(ISC_LOG_DEBUG(3), "dns_request_createvia: request %p",
request);
*requestp = request;
return (ISC_R_SUCCESS);
unlink:
LOCK(&requestmgr->lock);
ISC_LIST_UNLINK(requestmgr->requests, request, link);
UNLOCK(&requestmgr->lock);
cleanup:
if (tclone != NULL)
isc_task_detach(&tclone);
req_destroy(request);
req_log(ISC_LOG_DEBUG(3), "dns_request_createvia: failed %s",
dns_result_totext(result));
return (result);
}
static isc_result_t
req_render(dns_message_t *message, isc_buffer_t **bufferp,
unsigned int options, isc_mem_t *mctx)
{
isc_buffer_t *buf1 = NULL;
isc_buffer_t *buf2 = NULL;
isc_result_t result;
isc_region_t r;
isc_boolean_t tcp = ISC_FALSE;
dns_compress_t cctx;
isc_boolean_t cleanup_cctx = ISC_FALSE;
REQUIRE(bufferp != NULL && *bufferp == NULL);
req_log(ISC_LOG_DEBUG(3), "request_render");
/*
* Create buffer able to hold largest possible message.
*/
result = isc_buffer_allocate(mctx, &buf1, 65535);
if (result != ISC_R_SUCCESS)
return (result);
result = dns_compress_init(&cctx, -1, mctx);
if (result != ISC_R_SUCCESS)
return (result);
cleanup_cctx = ISC_TRUE;
/*
* Render message.
*/
result = dns_message_renderbegin(message, &cctx, buf1);
if (result != ISC_R_SUCCESS)
goto cleanup;
result = dns_message_rendersection(message, DNS_SECTION_QUESTION, 0);
if (result != ISC_R_SUCCESS)
goto cleanup;
result = dns_message_rendersection(message, DNS_SECTION_ANSWER, 0);
if (result != ISC_R_SUCCESS)
goto cleanup;
result = dns_message_rendersection(message, DNS_SECTION_AUTHORITY, 0);
if (result != ISC_R_SUCCESS)
goto cleanup;
result = dns_message_rendersection(message, DNS_SECTION_ADDITIONAL, 0);
if (result != ISC_R_SUCCESS)
goto cleanup;
result = dns_message_renderend(message);
if (result != ISC_R_SUCCESS)
goto cleanup;
dns_compress_invalidate(&cctx);
cleanup_cctx = ISC_FALSE;
/*
* Copy rendered message to exact sized buffer.
*/
isc_buffer_usedregion(buf1, &r);
if ((options & DNS_REQUESTOPT_TCP) != 0) {
tcp = ISC_TRUE;
} else if (r.length > 512) {
result = DNS_R_USETCP;
goto cleanup;
}
result = isc_buffer_allocate(mctx, &buf2, r.length + (tcp ? 2 : 0));
if (result != ISC_R_SUCCESS)
goto cleanup;
if (tcp)
isc_buffer_putuint16(buf2, (isc_uint16_t)r.length);
result = isc_buffer_copyregion(buf2, &r);
if (result != ISC_R_SUCCESS)
goto cleanup;
/*
* Cleanup and return.
*/
isc_buffer_free(&buf1);
*bufferp = buf2;
return (ISC_R_SUCCESS);
cleanup:
dns_message_renderreset(message);
if (buf1 != NULL)
isc_buffer_free(&buf1);
if (buf2 != NULL)
isc_buffer_free(&buf2);
if (cleanup_cctx)
dns_compress_invalidate(&cctx);
return (result);
}
/*
* If this request is no longer waiting for events,
* send the completion event. This will ultimately
* cause the request to be destroyed.
*
* Requires:
* 'request' is locked by the caller.
*/
static void
send_if_done(dns_request_t *request, isc_result_t result) {
if (!DNS_REQUEST_CONNECTING(request) &&
!DNS_REQUEST_SENDING(request) &&
!request->canceling)
req_sendevent(request, result);
}
/*
* Handle the control event.
*/
static void
do_cancel(isc_task_t *task, isc_event_t *event) {
dns_request_t *request = event->ev_arg;
UNUSED(task);
INSIST(event->ev_type == DNS_EVENT_REQUESTCONTROL);
LOCK(&request->requestmgr->locks[request->hash]);
request->canceling = ISC_FALSE;
if (!DNS_REQUEST_CANCELED(request))
req_cancel(request);
send_if_done(request, ISC_R_CANCELED);
UNLOCK(&request->requestmgr->locks[request->hash]);
}
void
dns_request_cancel(dns_request_t *request) {
REQUIRE(VALID_REQUEST(request));
req_log(ISC_LOG_DEBUG(3), "dns_request_cancel: request %p", request);
REQUIRE(VALID_REQUEST(request));
LOCK(&request->requestmgr->locks[request->hash]);
if (!request->canceling && !DNS_REQUEST_CANCELED(request)) {
isc_event_t *ev = &request->ctlevent;
isc_task_send(request->event->ev_sender, &ev);
request->canceling = ISC_TRUE;
}
UNLOCK(&request->requestmgr->locks[request->hash]);
}
isc_result_t
dns_request_getresponse(dns_request_t *request, dns_message_t *message,
unsigned int options)
{
isc_result_t result;
REQUIRE(VALID_REQUEST(request));
REQUIRE(request->answer != NULL);
req_log(ISC_LOG_DEBUG(3), "dns_request_getresponse: request %p",
request);
result = dns_message_setquerytsig(message, request->tsig);
if (result != ISC_R_SUCCESS)
return (result);
result = dns_message_settsigkey(message, request->tsigkey);
if (result != ISC_R_SUCCESS)
return (result);
result = dns_message_parse(message, request->answer, options);
if (result != ISC_R_SUCCESS)
return (result);
if (request->tsigkey != NULL)
result = dns_tsig_verify(request->answer, message, NULL, NULL);
return (result);
}
isc_boolean_t
dns_request_usedtcp(dns_request_t *request) {
REQUIRE(VALID_REQUEST(request));
return (ISC_TF((request->flags & DNS_REQUEST_F_TCP) != 0));
}
void
dns_request_destroy(dns_request_t **requestp) {
dns_request_t *request;
REQUIRE(requestp != NULL && VALID_REQUEST(*requestp));
request = *requestp;
req_log(ISC_LOG_DEBUG(3), "dns_request_destroy: request %p", request);
LOCK(&request->requestmgr->lock);
LOCK(&request->requestmgr->locks[request->hash]);
ISC_LIST_UNLINK(request->requestmgr->requests, request, link);
INSIST(!DNS_REQUEST_CONNECTING(request));
INSIST(!DNS_REQUEST_SENDING(request));
UNLOCK(&request->requestmgr->locks[request->hash]);
UNLOCK(&request->requestmgr->lock);
/*
* These should have been cleaned up by req_cancel() before
* the completion event was sent.
*/
INSIST(!ISC_LINK_LINKED(request, link));
INSIST(request->dispentry == NULL);
INSIST(request->dispatch == NULL);
INSIST(request->timer == NULL);
req_destroy(request);
*requestp = NULL;
}
/***
*** Private: request.
***/
static void
req_connected(isc_task_t *task, isc_event_t *event) {
isc_socketevent_t *sevent = (isc_socketevent_t *)event;
isc_result_t result;
dns_request_t *request = event->ev_arg;
REQUIRE(event->ev_type == ISC_SOCKEVENT_CONNECT);
REQUIRE(VALID_REQUEST(request));
REQUIRE(DNS_REQUEST_CONNECTING(request));
req_log(ISC_LOG_DEBUG(3), "req_connected: request %p", request);
LOCK(&request->requestmgr->locks[request->hash]);
request->flags &= ~DNS_REQUEST_F_CONNECTING;
if (DNS_REQUEST_CANCELED(request)) {
/*
* Send delayed event.
*/
if (DNS_REQUEST_TIMEDOUT(request))
send_if_done(request, ISC_R_TIMEDOUT);
else
send_if_done(request, ISC_R_CANCELED);
} else {
dns_dispatch_starttcp(request->dispatch);
result = sevent->result;
if (result == ISC_R_SUCCESS)
result = req_send(request, task, NULL);
if (result != ISC_R_SUCCESS) {
req_cancel(request);
send_if_done(request, ISC_R_CANCELED);
}
}
UNLOCK(&request->requestmgr->locks[request->hash]);
isc_event_free(&event);
}
static void
req_senddone(isc_task_t *task, isc_event_t *event) {
isc_socketevent_t *sevent = (isc_socketevent_t *)event;
dns_request_t *request = event->ev_arg;
REQUIRE(event->ev_type == ISC_SOCKEVENT_SENDDONE);
REQUIRE(VALID_REQUEST(request));
REQUIRE(DNS_REQUEST_SENDING(request));
req_log(ISC_LOG_DEBUG(3), "req_senddone: request %p", request);
UNUSED(task);
LOCK(&request->requestmgr->locks[request->hash]);
request->flags &= ~DNS_REQUEST_F_SENDING;
if (DNS_REQUEST_CANCELED(request)) {
/*
* Send delayed event.
*/
if (DNS_REQUEST_TIMEDOUT(request))
send_if_done(request, ISC_R_TIMEDOUT);
else
send_if_done(request, ISC_R_CANCELED);
} else if (sevent->result != ISC_R_SUCCESS) {
req_cancel(request);
send_if_done(request, ISC_R_CANCELED);
}
UNLOCK(&request->requestmgr->locks[request->hash]);
isc_event_free(&event);
}
static void
req_response(isc_task_t *task, isc_event_t *event) {
isc_result_t result;
dns_request_t *request = event->ev_arg;
dns_dispatchevent_t *devent = (dns_dispatchevent_t *)event;
isc_region_t r;
REQUIRE(VALID_REQUEST(request));
REQUIRE(event->ev_type == DNS_EVENT_DISPATCH);
UNUSED(task);
req_log(ISC_LOG_DEBUG(3), "req_response: request %p: %s", request,
dns_result_totext(devent->result));
LOCK(&request->requestmgr->locks[request->hash]);
result = devent->result;
if (result != ISC_R_SUCCESS)
goto done;
/*
* Copy buffer to request.
*/
isc_buffer_usedregion(&devent->buffer, &r);
result = isc_buffer_allocate(request->mctx, &request->answer,
r.length);
if (result != ISC_R_SUCCESS)
goto done;
result = isc_buffer_copyregion(request->answer, &r);
if (result != ISC_R_SUCCESS)
isc_buffer_free(&request->answer);
done:
/*
* Cleanup.
*/
dns_dispatch_removeresponse(&request->dispentry, &devent);
req_cancel(request);
/*
* Send completion event.
*/
send_if_done(request, result);
UNLOCK(&request->requestmgr->locks[request->hash]);
}
static void
req_timeout(isc_task_t *task, isc_event_t *event) {
dns_request_t *request = event->ev_arg;
isc_result_t result;
REQUIRE(VALID_REQUEST(request));
req_log(ISC_LOG_DEBUG(3), "req_timeout: request %p", request);
UNUSED(task);
LOCK(&request->requestmgr->locks[request->hash]);
if (event->ev_type == ISC_TIMEREVENT_TICK &&
request->udpcount-- != 0) {
if (! DNS_REQUEST_SENDING(request)) {
result = req_send(request, task, &request->destaddr);
if (result != ISC_R_SUCCESS) {
req_cancel(request);
send_if_done(request, result);
}
}
} else {
request->flags |= DNS_REQUEST_F_TIMEDOUT;
req_cancel(request);
send_if_done(request, ISC_R_TIMEDOUT);
}
UNLOCK(&request->requestmgr->locks[request->hash]);
isc_event_free(&event);
}
static void
req_sendevent(dns_request_t *request, isc_result_t result) {
isc_task_t *task;
REQUIRE(VALID_REQUEST(request));
req_log(ISC_LOG_DEBUG(3), "req_sendevent: request %p", request);
/*
* Lock held by caller.
*/
task = request->event->ev_sender;
request->event->ev_sender = request;
request->event->result = result;
isc_task_sendanddetach(&task, (isc_event_t **)&request->event);
}
static void
req_destroy(dns_request_t *request) {
isc_mem_t *mctx;
REQUIRE(VALID_REQUEST(request));
req_log(ISC_LOG_DEBUG(3), "req_destroy: request %p", request);
request->magic = 0;
if (request->query != NULL)
isc_buffer_free(&request->query);
if (request->answer != NULL)
isc_buffer_free(&request->answer);
if (request->event != NULL)
isc_event_free((isc_event_t **)&request->event);
if (request->dispentry != NULL)
dns_dispatch_removeresponse(&request->dispentry, NULL);
if (request->dispatch != NULL)
dns_dispatch_detach(&request->dispatch);
if (request->timer != NULL)
isc_timer_detach(&request->timer);
if (request->tsig != NULL)
isc_buffer_free(&request->tsig);
if (request->tsigkey != NULL)
dns_tsigkey_detach(&request->tsigkey);
if (request->requestmgr != NULL)
requestmgr_detach(&request->requestmgr);
mctx = request->mctx;
isc_mem_put(mctx, request, sizeof(*request));
isc_mem_detach(&mctx);
}
/*
* Stop the current request. Must be called from the request's task.
*/
static void
req_cancel(dns_request_t *request) {
isc_socket_t *socket;
REQUIRE(VALID_REQUEST(request));
req_log(ISC_LOG_DEBUG(3), "req_cancel: request %p", request);
/*
* Lock held by caller.
*/
request->flags |= DNS_REQUEST_F_CANCELED;
if (request->timer != NULL)
isc_timer_detach(&request->timer);
if (request->dispentry != NULL)
dns_dispatch_removeresponse(&request->dispentry, NULL);
if (DNS_REQUEST_CONNECTING(request)) {
socket = dns_dispatch_getsocket(request->dispatch);
isc_socket_cancel(socket, NULL, ISC_SOCKCANCEL_CONNECT);
}
if (DNS_REQUEST_SENDING(request)) {
socket = dns_dispatch_getsocket(request->dispatch);
isc_socket_cancel(socket, NULL, ISC_SOCKCANCEL_SEND);
}
dns_dispatch_detach(&request->dispatch);
}
static void
req_log(int level, const char *fmt, ...) {
va_list ap;
va_start(ap, fmt);
isc_log_vwrite(dns_lctx, DNS_LOGCATEGORY_GENERAL,
DNS_LOGMODULE_REQUEST, level, fmt, ap);
va_end(ap);
}