diff options
Diffstat (limited to 'lib/dns/request.c')
| -rw-r--r-- | lib/dns/request.c | 1497 |
1 files changed, 1497 insertions, 0 deletions
diff --git a/lib/dns/request.c b/lib/dns/request.c new file mode 100644 index 0000000..af75668 --- /dev/null +++ b/lib/dns/request.c @@ -0,0 +1,1497 @@ +/* + * Copyright (C) 2004-2008 Internet Systems Consortium, Inc. ("ISC") + * Copyright (C) 2000-2002 Internet Software Consortium. + * + * Permission to use, copy, modify, and/or 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 1.82 2008/07/22 03:43:04 marka Exp $ */ + +/*! \file */ + +#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 isc_socket_t * req_getsocket(dns_request_t *request); +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; + unsigned int dispattr; + + 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); + UNUSED(socket); + if (dispatchv4 != NULL) { + dispattr = dns_dispatch_getattributes(dispatchv4); + REQUIRE((dispattr & DNS_DISPATCHATTR_UDP) != 0); + } + if (dispatchv6 != NULL) { + dispattr = dns_dispatch_getattributes(dispatchv6); + REQUIRE((dispattr & DNS_DISPATCHATTR_UDP) != 0); + } + + 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; + unsigned int dispattr; + + req_log(ISC_LOG_DEBUG(3), "req_send: request %p", request); + + REQUIRE(VALID_REQUEST(request)); + dispattr = dns_dispatch_getattributes(request->dispatch); + socket = req_getsocket(request); + isc_buffer_usedregion(request->query, &r); + /* + * We could connect the socket when we are using an exclusive dispatch + * as we do in resolver.c, but we prefer implementation simplicity + * at this moment. + */ + 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); +#ifndef BROKEN_TCP_BIND_BEFORE_CONNECT + if (srcaddr == NULL) { + isc_sockaddr_anyofpf(&bind_any, + isc_sockaddr_pf(destaddr)); + result = isc_socket_bind(socket, &bind_any, 0); + } else { + src = *srcaddr; + isc_sockaddr_setport(&src, 0); + result = isc_socket_bind(socket, &src, 0); + } + if (result != ISC_R_SUCCESS) + goto cleanup; +#endif + 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; + } + request->udpcount = udpretries; + + /* + * 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; + + result = dns_dispatch_addresponse2(request->dispatch, destaddr, task, + req_response, request, &id, + &request->dispentry, + requestmgr->socketmgr); + if (result != ISC_R_SUCCESS) + goto cleanup; + + socket = req_getsocket(request); + INSIST(socket != NULL); + + 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; + } + request->udpcount = udpretries; + + /* + * 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; + + result = dns_dispatch_addresponse2(request->dispatch, destaddr, task, + req_response, request, &id, + &request->dispentry, + requestmgr->socketmgr); + if (result != ISC_R_SUCCESS) + goto cleanup; + socket = req_getsocket(request); + INSIST(socket != NULL); + + 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 isc_socket_t * +req_getsocket(dns_request_t *request) { + unsigned int dispattr; + isc_socket_t *socket; + + dispattr = dns_dispatch_getattributes(request->dispatch); + if ((dispattr & DNS_DISPATCHATTR_EXCLUSIVE) != 0) { + INSIST(request->dispentry != NULL); + socket = dns_dispatch_getentrysocket(request->dispentry); + } else + socket = dns_dispatch_getsocket(request->dispatch); + + return (socket); +} + +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; + unsigned int dispattr; + + 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); + dispattr = dns_dispatch_getattributes(request->dispatch); + socket = NULL; + if (DNS_REQUEST_CONNECTING(request) || DNS_REQUEST_SENDING(request)) { + if ((dispattr & DNS_DISPATCHATTR_EXCLUSIVE) != 0) { + if (request->dispentry != NULL) { + socket = dns_dispatch_getentrysocket( + request->dispentry); + } + } else + socket = dns_dispatch_getsocket(request->dispatch); + if (DNS_REQUEST_CONNECTING(request) && socket != NULL) + isc_socket_cancel(socket, NULL, ISC_SOCKCANCEL_CONNECT); + if (DNS_REQUEST_SENDING(request) && socket != NULL) + isc_socket_cancel(socket, NULL, ISC_SOCKCANCEL_SEND); + } + if (request->dispentry != NULL) + dns_dispatch_removeresponse(&request->dispentry, NULL); + 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); +} |