client.c revision 443b9e6e51e5addb020fc4832e84b81a38765328
94bd918b63001277f1b28ae4581645f8a835688fBob Halley/*
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * Copyright (C) 1999, 2000 Internet Software Consortium.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley *
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * Permission to use, copy, modify, and distribute this software for any
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * purpose with or without fee is hereby granted, provided that the above
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * copyright notice and this permission notice appear in all copies.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley *
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * SOFTWARE.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <config.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <string.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <isc/assertions.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <isc/mem.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <isc/mutex.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <isc/result.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <isc/task.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <isc/timer.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <isc/util.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <dns/acl.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <dns/dispatch.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <dns/events.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <dns/message.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <dns/rdata.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <dns/rdatalist.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <dns/rdataset.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <dns/view.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <dns/zone.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <named/client.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <named/globals.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <named/interfacemgr.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <named/log.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <named/notify.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <named/query.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <named/server.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#include <named/update.h>
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley/***
94bd918b63001277f1b28ae4581645f8a835688fBob Halley *** Client
94bd918b63001277f1b28ae4581645f8a835688fBob Halley ***/
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley/*
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * Important note!
94bd918b63001277f1b28ae4581645f8a835688fBob Halley *
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * All client state changes, other than that from idle to listening, occur
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * as a result of events. This guarantees serialization and avoids the
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * need for locking.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley *
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * If a routine is ever created that allows someone other than the client's
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * task to change the client, then the client will have to be locked.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#define NS_CLIENT_TRACE
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#ifdef NS_CLIENT_TRACE
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#define CTRACE(m) isc_log_write(ns_g_lctx, \
94bd918b63001277f1b28ae4581645f8a835688fBob Halley NS_LOGCATEGORY_CLIENT, \
94bd918b63001277f1b28ae4581645f8a835688fBob Halley NS_LOGMODULE_CLIENT, \
94bd918b63001277f1b28ae4581645f8a835688fBob Halley ISC_LOG_DEBUG(3), \
94bd918b63001277f1b28ae4581645f8a835688fBob Halley "client %p: %s", client, (m))
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#define MTRACE(m) isc_log_write(ns_g_lctx, \
94bd918b63001277f1b28ae4581645f8a835688fBob Halley NS_LOGCATEGORY_GENERAL, \
94bd918b63001277f1b28ae4581645f8a835688fBob Halley NS_LOGMODULE_CLIENT, \
94bd918b63001277f1b28ae4581645f8a835688fBob Halley ISC_LOG_DEBUG(3), \
94bd918b63001277f1b28ae4581645f8a835688fBob Halley "clientmgr %p: %s", manager, (m))
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#endif
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#define TCP_CLIENT(c) (((c)->attributes & NS_CLIENTATTR_TCP) != 0)
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#define SEND_BUFFER_SIZE 2048
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halleystruct ns_clientmgr {
94bd918b63001277f1b28ae4581645f8a835688fBob Halley /* Unlocked. */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley unsigned int magic;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley isc_mem_t * mctx;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley isc_taskmgr_t * taskmgr;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley isc_timermgr_t * timermgr;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley isc_mutex_t lock;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley /* Locked by lock. */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley isc_boolean_t exiting;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley client_list_t active; /* Active clients */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley client_list_t inactive; /* To be recycled */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley};
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#define MANAGER_MAGIC 0x4E53436DU /* NSCm */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#define VALID_MANAGER(m) ((m) != NULL && \
94bd918b63001277f1b28ae4581645f8a835688fBob Halley (m)->magic == MANAGER_MAGIC)
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley/*
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * Client object states. Ordering is significant: higher-numbered
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * states are generally "more active", meaning that the client can
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * have more dynamically allocated data, outstanding events, etc.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * In the list below, any such properties listed for state N
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * also apply to any state > N.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley *
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * To force the client into a less active state, set client->newstate
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * to that state and call exit_check(). This will cause any
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * activities defined for higher-numbered states to be aborted.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#define NS_CLIENTSTATE_FREED 0
94bd918b63001277f1b28ae4581645f8a835688fBob Halley/*
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * The client object no longer exists.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#define NS_CLIENTSTATE_INACTIVE 1
94bd918b63001277f1b28ae4581645f8a835688fBob Halley/*
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * The client object exists and has a task and timer.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * Its "query" struct and sendbuf are initialized.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * It is on the client manager's list of inactive clients.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * It has a message and OPT, both in the reset state.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#define NS_CLIENTSTATE_READY 2
94bd918b63001277f1b28ae4581645f8a835688fBob Halley/*
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * The client object is either a TCP or a UDP one, and
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * it is associated with a network interface. It is on the
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * client manager's list of active clients.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley *
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * If it is a TCP client object, it has a TCP listener socket
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * and an outstading TCP listen request.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley *
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * If it is a UDP client object, it is associated with a
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * dispatch and has an outstanding dispatch request.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#define NS_CLIENTSTATE_READING 3
94bd918b63001277f1b28ae4581645f8a835688fBob Halley/*
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * The client object is a TCP client object that has received
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * a connection. It has a tcpsocket, tcpmsg, TCP quota, and an
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * outstanding TCP read request. This state is not used for
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * UDP client objects.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#define NS_CLIENTSTATE_WORKING 4
94bd918b63001277f1b28ae4581645f8a835688fBob Halley/*
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * The client object has received a request and is working
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * on it. It has a view, and it may have any of a non-reset OPT,
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * recursion quota, and an outstanding write request. If it
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * is a UDP client object, it has a dispatch event.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley#define NS_CLIENTSTATE_MAX 9
94bd918b63001277f1b28ae4581645f8a835688fBob Halley/*
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * Sentinel value used to indicate "no state". When client->newstate
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * has this value, we are not attempting to exit the current state.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * Must be greater than any valid state.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halleystatic void client_read(ns_client_t *client);
94bd918b63001277f1b28ae4581645f8a835688fBob Halleystatic void client_accept(ns_client_t *client);
94bd918b63001277f1b28ae4581645f8a835688fBob Halleystatic void clientmgr_destroy(ns_clientmgr_t *manager);
94bd918b63001277f1b28ae4581645f8a835688fBob Halleystatic isc_boolean_t exit_check(ns_client_t *client);
94bd918b63001277f1b28ae4581645f8a835688fBob Halleystatic void ns_client_endrequest(ns_client_t *client);
94bd918b63001277f1b28ae4581645f8a835688fBob Halleystatic void ns_client_checkactive(ns_client_t *client);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley/*
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * Format a human-readable representation of the socket address '*sa'
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * into the character array 'array', which is of size 'size'.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * The resulting string is guaranteed to be null-terminated.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley */
94bd918b63001277f1b28ae4581645f8a835688fBob Halleystatic void
94bd918b63001277f1b28ae4581645f8a835688fBob Halleysockaddr_format(isc_sockaddr_t *sa, char *array, unsigned int size)
94bd918b63001277f1b28ae4581645f8a835688fBob Halley{
94bd918b63001277f1b28ae4581645f8a835688fBob Halley isc_result_t result;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley isc_buffer_t buf;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley isc_buffer_init(&buf, array, size, ISC_BUFFERTYPE_TEXT);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley result = isc_sockaddr_totext(sa, &buf);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (result != ISC_R_SUCCESS) {
94bd918b63001277f1b28ae4581645f8a835688fBob Halley strncpy(array, "<unknown address>", size);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley array[size-1] = '\0';
94bd918b63001277f1b28ae4581645f8a835688fBob Halley }
94bd918b63001277f1b28ae4581645f8a835688fBob Halley}
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley/*
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * Enter the inactive state.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley *
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * Requires:
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * No requests are outstanding.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley */
94bd918b63001277f1b28ae4581645f8a835688fBob Halleystatic void
94bd918b63001277f1b28ae4581645f8a835688fBob Halleyclient_deactivate(ns_client_t *client) {
94bd918b63001277f1b28ae4581645f8a835688fBob Halley REQUIRE(NS_CLIENT_VALID(client));
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (client->interface)
94bd918b63001277f1b28ae4581645f8a835688fBob Halley ns_interface_detach(&client->interface);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley INSIST(client->naccepts == 0);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (client->tcplistener != NULL)
94bd918b63001277f1b28ae4581645f8a835688fBob Halley isc_socket_detach(&client->tcplistener);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (client->dispentry != NULL) {
94bd918b63001277f1b28ae4581645f8a835688fBob Halley dns_dispatchevent_t **deventp;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (client->dispevent != NULL)
94bd918b63001277f1b28ae4581645f8a835688fBob Halley deventp = &client->dispevent;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley else
94bd918b63001277f1b28ae4581645f8a835688fBob Halley deventp = NULL;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley dns_dispatch_removerequest(client->dispatch,
94bd918b63001277f1b28ae4581645f8a835688fBob Halley &client->dispentry,
94bd918b63001277f1b28ae4581645f8a835688fBob Halley deventp);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley }
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (client->dispatch != NULL)
94bd918b63001277f1b28ae4581645f8a835688fBob Halley dns_dispatch_detach(&client->dispatch);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley client->attributes = 0;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley client->mortal = ISC_FALSE;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley LOCK(&client->manager->lock);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley ISC_LIST_UNLINK(client->manager->active, client, link);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley ISC_LIST_APPEND(client->manager->inactive, client, link);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley client->list = &client->manager->inactive;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley UNLOCK(&client->manager->lock);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley}
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley/*
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * Clean up a client object and free its memory.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * Requires:
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * The client is in the inactive state.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halleystatic void
94bd918b63001277f1b28ae4581645f8a835688fBob Halleyclient_free(ns_client_t *client) {
94bd918b63001277f1b28ae4581645f8a835688fBob Halley isc_boolean_t need_clientmgr_destroy = ISC_FALSE;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley ns_clientmgr_t *manager = NULL;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley REQUIRE(NS_CLIENT_VALID(client));
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley /*
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * When "shuttingdown" is true, either the task has received
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * its shutdown event or no shutdown event has ever been
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * set up. Thus, we have no outstanding shutdown
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * event at this point.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley REQUIRE(client->state == NS_CLIENTSTATE_INACTIVE);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley ns_query_free(client);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley isc_mem_put(client->mctx, client->sendbuf, SEND_BUFFER_SIZE);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley isc_timer_detach(&client->timer);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (client->opt != NULL) {
94bd918b63001277f1b28ae4581645f8a835688fBob Halley INSIST(dns_rdataset_isassociated(client->opt));
94bd918b63001277f1b28ae4581645f8a835688fBob Halley dns_rdataset_disassociate(client->opt);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley dns_message_puttemprdataset(client->message, &client->opt);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley }
94bd918b63001277f1b28ae4581645f8a835688fBob Halley dns_message_destroy(&client->message);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (client->task != NULL)
94bd918b63001277f1b28ae4581645f8a835688fBob Halley isc_task_detach(&client->task);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (client->manager != NULL) {
94bd918b63001277f1b28ae4581645f8a835688fBob Halley manager = client->manager;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley LOCK(&manager->lock);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley ISC_LIST_UNLINK(*client->list, client, link);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley client->list = NULL;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (manager->exiting &&
94bd918b63001277f1b28ae4581645f8a835688fBob Halley ISC_LIST_EMPTY(manager->active) &&
94bd918b63001277f1b28ae4581645f8a835688fBob Halley ISC_LIST_EMPTY(manager->inactive))
94bd918b63001277f1b28ae4581645f8a835688fBob Halley need_clientmgr_destroy = ISC_TRUE;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley UNLOCK(&manager->lock);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley }
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley CTRACE("free");
94bd918b63001277f1b28ae4581645f8a835688fBob Halley client->magic = 0;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley isc_mem_put(client->mctx, client, sizeof *client);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (need_clientmgr_destroy)
94bd918b63001277f1b28ae4581645f8a835688fBob Halley clientmgr_destroy(manager);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley}
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halleystatic void
94bd918b63001277f1b28ae4581645f8a835688fBob Halleyset_timeout(ns_client_t *client, unsigned int seconds) {
94bd918b63001277f1b28ae4581645f8a835688fBob Halley isc_result_t result;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley isc_interval_t interval;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley isc_interval_set(&interval, seconds, 0);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley result = isc_timer_reset(client->timer, isc_timertype_once, NULL,
94bd918b63001277f1b28ae4581645f8a835688fBob Halley &interval, ISC_FALSE);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (result != ISC_R_SUCCESS) {
94bd918b63001277f1b28ae4581645f8a835688fBob Halley isc_log_write(dns_lctx, NS_LOGCATEGORY_CLIENT,
94bd918b63001277f1b28ae4581645f8a835688fBob Halley NS_LOGMODULE_CLIENT, ISC_LOG_ERROR,
94bd918b63001277f1b28ae4581645f8a835688fBob Halley "setting timouet: %s",
94bd918b63001277f1b28ae4581645f8a835688fBob Halley isc_result_totext(result));
94bd918b63001277f1b28ae4581645f8a835688fBob Halley /* Continue anyway. */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley }
94bd918b63001277f1b28ae4581645f8a835688fBob Halley}
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley/*
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * Check for a deactivation or shutdown request and take appropriate
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * action. Returns ISC_TRUE if either is in progress; in this case
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * the caller must no longer use the client object as it may have been
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * freed.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley */
94bd918b63001277f1b28ae4581645f8a835688fBob Halleystatic isc_boolean_t
94bd918b63001277f1b28ae4581645f8a835688fBob Halleyexit_check(ns_client_t *client) {
94bd918b63001277f1b28ae4581645f8a835688fBob Halley REQUIRE(NS_CLIENT_VALID(client));
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (client->state <= client->newstate)
94bd918b63001277f1b28ae4581645f8a835688fBob Halley return (ISC_FALSE); /* Business as usual. */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley INSIST(client->newstate < NS_CLIENTSTATE_WORKING);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley /*
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * We need to detach from the view early when shutting down
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * the server to break the following vicious circle:
94bd918b63001277f1b28ae4581645f8a835688fBob Halley *
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * - The resolver will not shut down until the view refcount is zero
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * - The view refcount does not go to zero until all clients detach
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * - The client does not detach from the view until references is zero
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * - references does not go to zero until the resolver has shut down
94bd918b63001277f1b28ae4581645f8a835688fBob Halley *
94bd918b63001277f1b28ae4581645f8a835688fBob Halley */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (client->newstate == NS_CLIENTSTATE_FREED && client->view != NULL)
94bd918b63001277f1b28ae4581645f8a835688fBob Halley dns_view_detach(&client->view);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (client->state == NS_CLIENTSTATE_WORKING) {
94bd918b63001277f1b28ae4581645f8a835688fBob Halley INSIST(client->newstate <= NS_CLIENTSTATE_READING);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley /*
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * We are trying to abort request processing.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (client->nsends > 0) {
94bd918b63001277f1b28ae4581645f8a835688fBob Halley isc_socket_t *socket;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (TCP_CLIENT(client))
94bd918b63001277f1b28ae4581645f8a835688fBob Halley socket = client->tcpsocket;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley else
94bd918b63001277f1b28ae4581645f8a835688fBob Halley socket =
94bd918b63001277f1b28ae4581645f8a835688fBob Halley dns_dispatch_getsocket(client->dispatch);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley isc_socket_cancel(socket, client->task,
94bd918b63001277f1b28ae4581645f8a835688fBob Halley ISC_SOCKCANCEL_SEND);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley }
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (! (client->nsends == 0 && client->references == 0)) {
94bd918b63001277f1b28ae4581645f8a835688fBob Halley /*
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * Still waiting for I/O cancel completion.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * or lingering references.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley return (ISC_TRUE);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley }
94bd918b63001277f1b28ae4581645f8a835688fBob Halley /*
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * I/O cancel is complete. Burn down all state
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * related to the current request.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley ns_client_endrequest(client);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley client->state = NS_CLIENTSTATE_READING;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (NS_CLIENTSTATE_READING == client->newstate) {
94bd918b63001277f1b28ae4581645f8a835688fBob Halley client_read(client);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley client->newstate = NS_CLIENTSTATE_MAX;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley return (ISC_TRUE); /* We're done. */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley }
94bd918b63001277f1b28ae4581645f8a835688fBob Halley }
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (client->state == NS_CLIENTSTATE_READING) {
94bd918b63001277f1b28ae4581645f8a835688fBob Halley /*
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * We are trying to abort the current TCP connection,
94bd918b63001277f1b28ae4581645f8a835688fBob Halley * if any.
94bd918b63001277f1b28ae4581645f8a835688fBob Halley */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley INSIST(client->newstate <= NS_CLIENTSTATE_READY);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley CTRACE("closetcp");
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (client->nreads > 0)
94bd918b63001277f1b28ae4581645f8a835688fBob Halley dns_tcpmsg_cancelread(&client->tcpmsg);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (! client->nreads == 0) {
94bd918b63001277f1b28ae4581645f8a835688fBob Halley /* Still waiting for read cancel completion. */
94bd918b63001277f1b28ae4581645f8a835688fBob Halley return (ISC_TRUE);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley }
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (client->tcpmsg_valid) {
94bd918b63001277f1b28ae4581645f8a835688fBob Halley dns_tcpmsg_invalidate(&client->tcpmsg);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley client->tcpmsg_valid = ISC_FALSE;
94bd918b63001277f1b28ae4581645f8a835688fBob Halley }
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (client->tcpsocket != NULL)
94bd918b63001277f1b28ae4581645f8a835688fBob Halley isc_socket_detach(&client->tcpsocket);
94bd918b63001277f1b28ae4581645f8a835688fBob Halley
94bd918b63001277f1b28ae4581645f8a835688fBob Halley if (client->tcpquota != NULL)
isc_quota_detach(&client->tcpquota);
(void) isc_timer_reset(client->timer, isc_timertype_inactive,
NULL, NULL, ISC_TRUE);
client->state = NS_CLIENTSTATE_READY;
/*
* Now the client is ready to accept a new TCP connection
* or UDP request, but we may have enough clients doing
* that already. Check whether this client needs to remain
* active and force it to go inactive if not.
*/
ns_client_checkactive(client);
if (NS_CLIENTSTATE_READY == client->newstate) {
if (TCP_CLIENT(client)) {
client_accept(client);
} else {
/*
* Give the processed dispatch event back to
* the dispatch. This tells the dispatch
* that we are ready to receive the next event.
*/
dns_dispatch_freeevent(client->dispatch,
client->dispentry,
&client->dispevent);
}
client->newstate = NS_CLIENTSTATE_MAX;
return (ISC_TRUE);
}
}
if (client->state == NS_CLIENTSTATE_READY) {
INSIST(client->newstate <= NS_CLIENTSTATE_INACTIVE);
/*
* We are trying to enter the inactive state.
*/
if (client->naccepts > 0)
isc_socket_cancel(client->tcplistener, client->task,
ISC_SOCKCANCEL_ACCEPT);
if (! (client->naccepts == 0)) {
/* Still waiting for accept cancel completion. */
return (ISC_TRUE);
}
/* Accept cancel is complete. */
client_deactivate(client);
client->state = NS_CLIENTSTATE_INACTIVE;
if (client->state == client->newstate) {
client->newstate = NS_CLIENTSTATE_MAX;
return (ISC_TRUE); /* We're done. */
}
}
if (client->state == NS_CLIENTSTATE_INACTIVE) {
INSIST(client->newstate == NS_CLIENTSTATE_FREED);
/*
* We are trying to free the client.
*/
client_free(client);
return (ISC_TRUE);
}
return (ISC_TRUE);
}
/*
* The client's task has received a shutdown event.
*/
static void
client_shutdown(isc_task_t *task, isc_event_t *event) {
ns_client_t *client;
REQUIRE(event != NULL);
REQUIRE(event->type == ISC_TASKEVENT_SHUTDOWN);
client = event->arg;
REQUIRE(NS_CLIENT_VALID(client));
REQUIRE(task == client->task);
CTRACE("shutdown");
isc_event_free(&event);
if (client->shutdown != NULL) {
(client->shutdown)(client->shutdown_arg, ISC_R_SHUTTINGDOWN);
client->shutdown = NULL;
client->shutdown_arg = NULL;
}
client->newstate = NS_CLIENTSTATE_FREED;
(void) exit_check(client);
}
static void
ns_client_endrequest(ns_client_t *client) {
INSIST(client->naccepts == 0);
INSIST(client->nreads == 0);
INSIST(client->nsends == 0);
INSIST(client->lockview == NULL);
CTRACE("endrequest");
INSIST(client->state == NS_CLIENTSTATE_WORKING);
if (client->next != NULL) {
(client->next)(client);
client->next = NULL;
}
if (client->view != NULL)
dns_view_detach(&client->view);
if (client->opt != NULL) {
INSIST(dns_rdataset_isassociated(client->opt));
dns_rdataset_disassociate(client->opt);
dns_message_puttemprdataset(client->message, &client->opt);
}
client->udpsize = 512;
dns_message_reset(client->message, DNS_MESSAGE_INTENTPARSE);
if (client->recursionquota != NULL)
isc_quota_detach(&client->recursionquota);
}
static void
ns_client_checkactive(ns_client_t *client) {
if (client->mortal) {
/*
* This client object should normally go inactive
* at this point, but if we have fewer active client
* objects than desired due to earlier quota exhaustion,
* keep it active to make up for the shortage.
*/
isc_boolean_t need_another_client = ISC_FALSE;
if (TCP_CLIENT(client)) {
LOCK(&client->interface->lock);
if (client->interface->ntcpcurrent <
client->interface->ntcptarget)
need_another_client = ISC_TRUE;
UNLOCK(&client->interface->lock);
} else {
/*
* The UDP client quota is enforced by making
* requests fail rather than by not listening
* for new ones. Therefore, there is always a
* full set of UDP clients listening.
*/
}
if (! need_another_client) {
/*
* We don't need this client object. Recycle it.
*/
if (client->newstate >= NS_CLIENTSTATE_INACTIVE)
client->newstate = NS_CLIENTSTATE_INACTIVE;
}
}
}
void
ns_client_next(ns_client_t *client, isc_result_t result) {
int newstate;
REQUIRE(NS_CLIENT_VALID(client));
REQUIRE(client->state == NS_CLIENTSTATE_WORKING);
CTRACE("next");
if (result != ISC_R_SUCCESS) {
isc_log_write(dns_lctx, DNS_LOGCATEGORY_SECURITY,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(3),
"request failed: %s", isc_result_totext(result));
}
/*
* An error processing a TCP request may have left
* the connection out of sync. To be safe, we always
* sever the connection when result != ISC_R_SUCCESS.
*/
if (result == ISC_R_SUCCESS && TCP_CLIENT(client))
newstate = NS_CLIENTSTATE_READING;
else
newstate = NS_CLIENTSTATE_READY;
if (client->newstate > newstate)
client->newstate = newstate;
(void) exit_check(client);
}
static void
client_senddone(isc_task_t *task, isc_event_t *event) {
ns_client_t *client;
isc_socketevent_t *sevent = (isc_socketevent_t *) event;
REQUIRE(sevent != NULL);
REQUIRE(sevent->type == ISC_SOCKEVENT_SENDDONE);
client = sevent->arg;
REQUIRE(NS_CLIENT_VALID(client));
REQUIRE(task == client->task);
CTRACE("senddone");
INSIST(client->nsends > 0);
client->nsends--;
isc_event_free(&event);
if (exit_check(client))
return;
ns_client_next(client, ISC_R_SUCCESS);
}
void
ns_client_send(ns_client_t *client) {
isc_result_t result;
unsigned char *data;
isc_buffer_t buffer;
isc_buffer_t tcpbuffer;
isc_region_t r;
isc_socket_t *socket;
isc_sockaddr_t *address;
unsigned int bufsize = 512;
REQUIRE(NS_CLIENT_VALID(client));
CTRACE("send");
if ((client->attributes & NS_CLIENTATTR_RA) != 0)
client->message->flags |= DNS_MESSAGEFLAG_RA;
data = client->sendbuf;
/*
* XXXRTH The following doesn't deal with TSIGs, TCP buffer resizing,
* or ENDS1 more data packets.
*/
if (TCP_CLIENT(client)) {
/*
* XXXRTH "tcpbuffer" is a hack to get things working.
*/
isc_buffer_init(&tcpbuffer, data, SEND_BUFFER_SIZE,
ISC_BUFFERTYPE_BINARY);
isc_buffer_init(&buffer, data + 2, SEND_BUFFER_SIZE - 2,
ISC_BUFFERTYPE_BINARY);
} else {
if (client->udpsize < SEND_BUFFER_SIZE)
bufsize = client->udpsize;
else
bufsize = SEND_BUFFER_SIZE;
isc_buffer_init(&buffer, data, bufsize, ISC_BUFFERTYPE_BINARY);
}
result = dns_message_renderbegin(client->message, &buffer);
if (result != ISC_R_SUCCESS)
goto done;
if (client->opt != NULL) {
result = dns_message_setopt(client->message, client->opt);
if (result != ISC_R_SUCCESS)
goto done;
/*
* XXXRTH dns_message_setopt() should probably do this...
*/
client->opt = NULL;
}
result = dns_message_rendersection(client->message,
DNS_SECTION_QUESTION, 0);
if (result != ISC_R_SUCCESS)
goto done;
result = dns_message_rendersection(client->message,
DNS_SECTION_ANSWER, 0);
if (result == ISC_R_NOSPACE) {
client->message->flags |= DNS_MESSAGEFLAG_TC;
goto renderend;
}
if (result != ISC_R_SUCCESS)
goto done;
result = dns_message_rendersection(client->message,
DNS_SECTION_AUTHORITY, 0);
if (result == ISC_R_NOSPACE) {
client->message->flags |= DNS_MESSAGEFLAG_TC;
goto renderend;
}
if (result != ISC_R_SUCCESS)
goto done;
result = dns_message_rendersection(client->message,
DNS_SECTION_ADDITIONAL, 0);
if (result != ISC_R_SUCCESS && result != ISC_R_NOSPACE)
goto done;
renderend:
result = dns_message_renderend(client->message);
if (result != ISC_R_SUCCESS)
goto done;
if (TCP_CLIENT(client)) {
socket = client->tcpsocket;
address = NULL;
isc_buffer_used(&buffer, &r);
isc_buffer_putuint16(&tcpbuffer, (isc_uint16_t) r.length);
isc_buffer_add(&tcpbuffer, r.length);
isc_buffer_used(&tcpbuffer, &r);
} else {
socket = dns_dispatch_getsocket(client->dispatch);
address = &client->dispevent->addr;
isc_buffer_used(&buffer, &r);
}
CTRACE("sendto");
result = isc_socket_sendto(socket, &r, client->task, client_senddone,
client, address, NULL);
if (result == ISC_R_SUCCESS) {
client->nsends++;
return;
}
done:
ns_client_next(client, result);
}
void
ns_client_error(ns_client_t *client, isc_result_t result) {
dns_rcode_t rcode;
dns_message_t *message;
REQUIRE(NS_CLIENT_VALID(client));
CTRACE("error");
message = client->message;
rcode = dns_result_torcode(result);
/*
* message may be an in-progress reply that we had trouble
* with, in which case QR will be set. We need to clear QR before
* calling dns_message_reply() to avoid triggering an assertion.
*/
message->flags &= ~DNS_MESSAGEFLAG_QR;
/*
* AA and AD shouldn't be set.
*/
message->flags &= ~(DNS_MESSAGEFLAG_AA | DNS_MESSAGEFLAG_AD);
result = dns_message_reply(message, ISC_TRUE);
if (result != ISC_R_SUCCESS) {
/*
* It could be that we've got a query with a good header,
* but a bad question section, so we try again with
* want_question_section set to ISC_FALSE.
*/
result = dns_message_reply(message, ISC_FALSE);
if (result != ISC_R_SUCCESS) {
ns_client_next(client, result);
return;
}
}
message->rcode = rcode;
ns_client_send(client);
}
static inline isc_result_t
client_addopt(ns_client_t *client) {
dns_rdataset_t *rdataset;
dns_rdatalist_t *rdatalist;
dns_rdata_t *rdata;
isc_result_t result;
REQUIRE(client->opt == NULL); /* XXXRTH free old. */
rdatalist = NULL;
result = dns_message_gettemprdatalist(client->message, &rdatalist);
if (result != ISC_R_SUCCESS)
return (result);
rdata = NULL;
result = dns_message_gettemprdata(client->message, &rdata);
if (result != ISC_R_SUCCESS)
return (result);
rdataset = NULL;
result = dns_message_gettemprdataset(client->message, &rdataset);
if (result != ISC_R_SUCCESS)
return (result);
dns_rdataset_init(rdataset);
rdatalist->type = dns_rdatatype_opt;
rdatalist->covers = 0;
/*
* Set Maximum UDP buffer size.
*/
rdatalist->rdclass = SEND_BUFFER_SIZE;
/*
* Set EXTENDED-RCODE, VERSION, and Z to 0.
*/
rdatalist->ttl = 0;
/*
* No ENDS options.
*/
rdata->data = NULL;
rdata->length = 0;
ISC_LIST_INIT(rdatalist->rdata);
ISC_LIST_APPEND(rdatalist->rdata, rdata, link);
dns_rdatalist_tordataset(rdatalist, rdataset);
client->opt = rdataset;
return (ISC_R_SUCCESS);
}
/*
* Handle an incoming request event from the dispatch (UDP case)
* or tcpmsg (TCP case).
*/
static void
client_request(isc_task_t *task, isc_event_t *event) {
ns_client_t *client;
dns_dispatchevent_t *devent;
isc_result_t result;
isc_buffer_t *buffer;
dns_view_t *view;
dns_rdataset_t *opt;
isc_boolean_t ra; /* Recursion available. */
char peerbuf[256];
REQUIRE(event != NULL);
client = event->arg;
REQUIRE(NS_CLIENT_VALID(client));
REQUIRE(task == client->task);
INSIST(client->recursionquota == NULL);
INSIST(client->state ==
TCP_CLIENT(client) ?
NS_CLIENTSTATE_READING :
NS_CLIENTSTATE_READY);
RWLOCK(&ns_g_server->conflock, isc_rwlocktype_read);
dns_zonemgr_lockconf(ns_g_server->zonemgr, isc_rwlocktype_read);
if (event->type == DNS_EVENT_DISPATCH) {
INSIST(! TCP_CLIENT(client));
devent = (dns_dispatchevent_t *)event;
REQUIRE(client->dispentry != NULL);
client->dispevent = devent;
buffer = &devent->buffer;
result = devent->result;
client->peeraddr = devent->addr;
} else {
INSIST(TCP_CLIENT(client));
REQUIRE(event->type == DNS_EVENT_TCPMSG);
REQUIRE(event->sender == &client->tcpmsg);
buffer = &client->tcpmsg.buffer;
result = client->tcpmsg.result;
INSIST(client->nreads == 1);
/*
* client->peeraddr was set when the connection was accepted.
*/
client->nreads--;
}
sockaddr_format(&client->peeraddr, peerbuf, sizeof(peerbuf));
isc_log_write(ns_g_lctx, NS_LOGCATEGORY_CLIENT,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(3),
"client %p: %s request from %s",
client, TCP_CLIENT(client) ? "TCP" : "UDP",
peerbuf);
if (exit_check(client))
goto cleanup_serverlock;
client->state = NS_CLIENTSTATE_WORKING;
isc_stdtime_get(&client->requesttime);
client->now = client->requesttime;
set_timeout(client, 60);
if (result != ISC_R_SUCCESS) {
if (TCP_CLIENT(client))
ns_client_next(client, result);
else
isc_task_shutdown(client->task);
goto cleanup_serverlock;
}
result = dns_message_parse(client->message, buffer, ISC_FALSE);
if (result != ISC_R_SUCCESS) {
ns_client_error(client, result);
goto cleanup_serverlock;
}
/*
* We expect a query, not a response. Unexpected UDP responses
* are discarded early by the dispatcher, but TCP responses
* bypass the dispatcher and must be discarded here.
*/
if ((client->message->flags & DNS_MESSAGEFLAG_QR) != 0) {
CTRACE("unexpected response");
ns_client_next(client, DNS_R_FORMERR);
goto cleanup_serverlock;
}
/*
* Deal with EDNS.
*/
opt = dns_message_getopt(client->message);
if (opt != NULL) {
unsigned int version;
/*
* Set the client's UDP buffer size.
*/
client->udpsize = opt->rdclass;
/*
* Create an OPT for our reply.
*/
result = client_addopt(client);
if (result != ISC_R_SUCCESS) {
ns_client_error(client, result);
goto cleanup_serverlock;
}
/*
* Do we understand this version of ENDS?
*
* XXXRTH need library support for this!
*/
version = (opt->ttl & 0x00FF0000) >> 16;
if (version != 0) {
ns_client_error(client, DNS_R_BADVERS);
goto cleanup_serverlock;
}
}
/*
* XXXRTH View list management code will be moving to its own module
* soon.
*/
for (view = ISC_LIST_HEAD(ns_g_server->viewlist);
view != NULL;
view = ISC_LIST_NEXT(view, link)) {
/*
* XXXRTH View matching will become more powerful later.
*/
if (client->message->rdclass == view->rdclass ||
client->message->rdclass == dns_rdataclass_any)
{
dns_view_attach(view, &client->view);
break;
}
}
if (view == NULL) {
CTRACE("no view");
ns_client_error(client, DNS_R_REFUSED);
goto cleanup_serverlock;
}
/*
* Lock the view's configuration data for reading.
* We must attach a separate view reference for this
* purpose instad of using client->view, because
* client->view may or may not be detached at the point
* when whe return from this event handler depending
* on whether the request handler causes ns_client_next()
* to be called or not.
*/
dns_view_attach(client->view, &client->lockview);
RWLOCK(&client->lockview->conflock, isc_rwlocktype_read);
/*
* Check for a signature. We log bad signatures regardless of
* whether they ultimately cause the request to be rejected or
* not. We do not log the lack of a signature unless we are
* debugging.
*/
result = dns_message_checksig(client->message, client->view);
if (result != ISC_R_SUCCESS) {
ns_client_error(client, result);
goto cleanup_viewlock;
}
client->signer = NULL;
dns_name_init(&client->signername, NULL);
result = dns_message_signer(client->message, &client->signername);
if (result == DNS_R_SUCCESS) {
isc_log_write(dns_lctx, DNS_LOGCATEGORY_SECURITY,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(3),
"request has valid signature");
client->signer = &client->signername;
} else if (result == DNS_R_NOTFOUND) {
isc_log_write(dns_lctx, DNS_LOGCATEGORY_SECURITY,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(3),
"request is not signed");
} else if (result == DNS_R_NOIDENTITY) {
isc_log_write(dns_lctx, DNS_LOGCATEGORY_SECURITY,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(3),
"request is signed by a nonauthoritative key");
} else {
/* There is a signature, but it is bad. */
isc_log_write(dns_lctx, DNS_LOGCATEGORY_SECURITY,
NS_LOGMODULE_CLIENT, ISC_LOG_ERROR,
"request has invalid signature: %s",
isc_result_totext(result));
}
/*
* Decide whether recursive service is available to this client.
* We do this here rather than in the query code so that we can
* set the RA bit correctly on all kinds of responses, not just
* responses to ordinary queries.
*/
if (client->view->resolver == NULL) {
ra = ISC_FALSE;
} else {
ra = ISC_TRUE;
if (ns_g_server->recursion == ISC_TRUE) {
/* XXX ACL should be view specific. */
/* XXX this will log too much too early */
result = ns_client_checkacl(client, "recursion",
ns_g_server->recursionacl,
ISC_TRUE);
if (result != DNS_R_SUCCESS)
ra = ISC_FALSE;
}
}
if (ra == ISC_TRUE)
client->attributes |= NS_CLIENTATTR_RA;
/*
* Dispatch the request.
*/
switch (client->message->opcode) {
case dns_opcode_query:
CTRACE("query");
ns_query_start(client);
break;
case dns_opcode_update:
CTRACE("update");
ns_update_start(client);
break;
case dns_opcode_notify:
CTRACE("notify");
ns_notify_start(client);
break;
case dns_opcode_iquery:
CTRACE("iquery");
ns_client_error(client, DNS_R_NOTIMP);
break;
default:
CTRACE("unknown opcode");
ns_client_error(client, DNS_R_NOTIMP);
}
cleanup_viewlock:
RWUNLOCK(&client->lockview->conflock, isc_rwlocktype_read);
dns_view_detach(&client->lockview);
cleanup_serverlock:
dns_zonemgr_unlockconf(ns_g_server->zonemgr, isc_rwlocktype_read);
RWUNLOCK(&ns_g_server->conflock, isc_rwlocktype_read);
}
static void
client_timeout(isc_task_t *task, isc_event_t *event) {
ns_client_t *client;
REQUIRE(event != NULL);
REQUIRE(event->type == ISC_TIMEREVENT_LIFE ||
event->type == ISC_TIMEREVENT_IDLE);
client = event->arg;
REQUIRE(NS_CLIENT_VALID(client));
REQUIRE(task == client->task);
REQUIRE(client->timer != NULL);
CTRACE("timeout");
isc_event_free(&event);
if (client->shutdown != NULL) {
(client->shutdown)(client->shutdown_arg, ISC_R_TIMEDOUT);
client->shutdown = NULL;
client->shutdown_arg = NULL;
}
if (client->newstate > NS_CLIENTSTATE_READY)
client->newstate = NS_CLIENTSTATE_READY;
(void) exit_check(client);
}
static isc_result_t
client_create(ns_clientmgr_t *manager, ns_client_t **clientp)
{
ns_client_t *client;
isc_result_t result;
/*
* Caller must be holding the manager lock.
*
* Note: creating a client does not add the client to the
* manager's client list or set the client's manager pointer.
* The caller is responsible for that.
*/
REQUIRE(clientp != NULL && *clientp == NULL);
client = isc_mem_get(manager->mctx, sizeof *client);
if (client == NULL)
return (ISC_R_NOMEMORY);
client->task = NULL;
result = isc_task_create(manager->taskmgr, manager->mctx, 0,
&client->task);
if (result != ISC_R_SUCCESS)
goto cleanup_client;
isc_task_setname(client->task, "client", client);
result = isc_task_onshutdown(client->task, client_shutdown, client);
if (result != ISC_R_SUCCESS)
goto cleanup_task;
client->timer = NULL;
result = isc_timer_create(manager->timermgr, isc_timertype_inactive,
NULL, NULL, client->task, client_timeout,
client, &client->timer);
if (result != ISC_R_SUCCESS)
goto cleanup_task;
client->message = NULL;
result = dns_message_create(manager->mctx, DNS_MESSAGE_INTENTPARSE,
&client->message);
if (result != ISC_R_SUCCESS)
goto cleanup_timer;
/* XXXRTH Hardwired constants */
client->sendbuf = isc_mem_get(manager->mctx, SEND_BUFFER_SIZE);
if (client->sendbuf == NULL)
goto cleanup_message;
client->magic = NS_CLIENT_MAGIC;
client->mctx = manager->mctx;
client->manager = NULL;
client->state = NS_CLIENTSTATE_INACTIVE;
client->newstate = NS_CLIENTSTATE_MAX;
client->naccepts = 0;
client->nreads = 0;
client->nsends = 0;
client->references = 0;
client->attributes = 0;
client->view = NULL;
client->lockview = NULL;
client->dispatch = NULL;
client->dispentry = NULL;
client->dispevent = NULL;
client->tcplistener = NULL;
client->tcpsocket = NULL;
client->tcpmsg_valid = ISC_FALSE;
client->opt = NULL;
client->udpsize = 512;
client->next = NULL;
client->shutdown = NULL;
client->shutdown_arg = NULL;
dns_name_init(&client->signername, NULL);
client->mortal = ISC_FALSE;
client->tcpquota = NULL;
client->recursionquota = NULL;
client->interface = NULL;
ISC_LINK_INIT(client, link);
client->list = NULL;
/*
* We call the init routines for the various kinds of client here,
* after we have created an otherwise valid client, because some
* of them call routines that REQUIRE(NS_CLIENT_VALID(client)).
*/
result = ns_query_init(client);
if (result != ISC_R_SUCCESS)
goto cleanup_sendbuf;
CTRACE("create");
*clientp = client;
return (ISC_R_SUCCESS);
cleanup_sendbuf:
isc_mem_put(manager->mctx, client->sendbuf, SEND_BUFFER_SIZE);
client->magic = 0;
cleanup_message:
dns_message_destroy(&client->message);
cleanup_timer:
isc_timer_detach(&client->timer);
cleanup_task:
isc_task_detach(&client->task);
cleanup_client:
isc_mem_put(manager->mctx, client, sizeof *client);
return (result);
}
static void
client_read(ns_client_t *client) {
isc_result_t result;
CTRACE("read");
result = dns_tcpmsg_readmessage(&client->tcpmsg, client->task,
client_request, client);
if (result != ISC_R_SUCCESS)
goto fail;
/*
* Set a timeout to limit the amount of time we will wait
* for a request on this TCP connection.
*/
set_timeout(client, 30);
client->state = client->newstate = NS_CLIENTSTATE_READING;
INSIST(client->nreads == 0);
client->nreads++;
return;
fail:
ns_client_next(client, result);
}
static void
client_newconn(isc_task_t *task, isc_event_t *event) {
ns_client_t *client = event->arg;
isc_socket_newconnev_t *nevent = (isc_socket_newconnev_t *)event;
isc_result_t result;
char peerbuf[256];
REQUIRE(event->type == ISC_SOCKEVENT_NEWCONN);
REQUIRE(NS_CLIENT_VALID(client));
REQUIRE(client->task == task);
INSIST(client->state == NS_CLIENTSTATE_READY);
CTRACE("newconn");
INSIST(client->naccepts == 1);
client->naccepts--;
LOCK(&client->interface->lock);
INSIST(client->interface->ntcpcurrent > 0);
client->interface->ntcpcurrent--;
UNLOCK(&client->interface->lock);
/*
* We must take ownership of the new socket before the exit
* check to make sure it gets destroyed if we decide to exit.
*/
if (nevent->result == ISC_R_SUCCESS) {
client->tcpsocket = nevent->newsocket;
client->state = NS_CLIENTSTATE_READING;
(void) isc_socket_getpeername(client->tcpsocket,
&client->peeraddr);
sockaddr_format(&client->peeraddr, peerbuf, sizeof(peerbuf));
isc_log_write(ns_g_lctx, NS_LOGCATEGORY_CLIENT,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(3),
"client %p: TCP connection from %s",
client, peerbuf);
} else {
/*
* XXXRTH What should we do? We're trying to accept but
* it didn't work. If we just give up, then TCP
* service may eventually stop.
*
* For now, we just go idle.
*
* Going idle is probably the right thing if the
* I/O was canceled.
*/
isc_log_write(ns_g_lctx, NS_LOGCATEGORY_CLIENT,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(3),
"client %p: accept failed: %s", client,
isc_result_totext(nevent->result));
}
if (exit_check(client))
goto freeevent;
if (nevent->result == ISC_R_SUCCESS) {
INSIST(client->tcpmsg_valid == ISC_FALSE);
dns_tcpmsg_init(client->mctx, client->tcpsocket,
&client->tcpmsg);
client->tcpmsg_valid = ISC_TRUE;
/*
* Let a new client take our place immediately, before
* we wait for a request packet. If we don't,
* telnetting to port 35 (once per CPU) will
* deny service to legititmate TCP clients.
*/
result = isc_quota_attach(&ns_g_server->tcpquota,
&client->tcpquota);
if (result == ISC_R_SUCCESS)
result = ns_client_replace(client);
if (result != ISC_R_SUCCESS) {
isc_log_write(ns_g_lctx, NS_LOGCATEGORY_CLIENT,
NS_LOGMODULE_CLIENT, ISC_LOG_WARNING,
"no more TCP clients: %s",
isc_result_totext(result));
}
client_read(client);
}
freeevent:
isc_event_free(&event);
}
static void
client_accept(ns_client_t *client) {
isc_result_t result;
CTRACE("accept");
result = isc_socket_accept(client->tcplistener, client->task,
client_newconn, client);
if (result != ISC_R_SUCCESS) {
UNEXPECTED_ERROR(__FILE__, __LINE__,
"isc_socket_accept() failed: %s",
isc_result_totext(result));
/*
* XXXRTH What should we do? We're trying to accept but
* it didn't work. If we just give up, then TCP
* service may eventually stop.
*
* For now, we just go idle.
*/
return;
}
INSIST(client->naccepts == 0);
client->naccepts++;
LOCK(&client->interface->lock);
client->interface->ntcpcurrent++;
UNLOCK(&client->interface->lock);
}
void
ns_client_attach(ns_client_t *source, ns_client_t **targetp) {
REQUIRE(NS_CLIENT_VALID(source));
REQUIRE(targetp != NULL && *targetp == NULL);
source->references++;
*targetp = source;
}
void
ns_client_detach(ns_client_t **clientp) {
ns_client_t *client = *clientp;
client->references--;
INSIST(client->references >= 0);
*clientp = NULL;
(void) exit_check(client);
}
isc_boolean_t
ns_client_shuttingdown(ns_client_t *client) {
return (client->newstate == NS_CLIENTSTATE_FREED);
}
isc_result_t
ns_client_replace(ns_client_t *client) {
isc_result_t result;
CTRACE("replace");
result = ns_clientmgr_createclients(client->manager,
1, client->interface,
(TCP_CLIENT(client) ?
ISC_TRUE : ISC_FALSE));
if (result != ISC_R_SUCCESS)
return (result);
/*
* The responsibility for listening for new requests is hereby
* transferred to the new client. Therefore, the old client
* should refrain from listening for any more requests.
*/
client->mortal = ISC_TRUE;
return (ISC_R_SUCCESS);
}
/***
*** Client Manager
***/
static void
clientmgr_destroy(ns_clientmgr_t *manager) {
REQUIRE(ISC_LIST_EMPTY(manager->active));
REQUIRE(ISC_LIST_EMPTY(manager->inactive));
MTRACE("clientmgr_destroy");
manager->magic = 0;
isc_mem_put(manager->mctx, manager, sizeof *manager);
}
isc_result_t
ns_clientmgr_create(isc_mem_t *mctx, isc_taskmgr_t *taskmgr,
isc_timermgr_t *timermgr, ns_clientmgr_t **managerp)
{
ns_clientmgr_t *manager;
isc_result_t result;
manager = isc_mem_get(mctx, sizeof *manager);
if (manager == NULL)
return (ISC_R_NOMEMORY);
result = isc_mutex_init(&manager->lock);
if (result != ISC_R_SUCCESS)
goto cleanup_manager;
manager->mctx = mctx;
manager->taskmgr = taskmgr;
manager->timermgr = timermgr;
manager->exiting = ISC_FALSE;
ISC_LIST_INIT(manager->active);
ISC_LIST_INIT(manager->inactive);
manager->magic = MANAGER_MAGIC;
MTRACE("create");
*managerp = manager;
return (ISC_R_SUCCESS);
cleanup_manager:
isc_mem_put(manager->mctx, manager, sizeof *manager);
return (result);
}
void
ns_clientmgr_destroy(ns_clientmgr_t **managerp) {
ns_clientmgr_t *manager;
ns_client_t *client;
isc_boolean_t need_destroy = ISC_FALSE;
REQUIRE(managerp != NULL);
manager = *managerp;
REQUIRE(VALID_MANAGER(manager));
MTRACE("destroy");
LOCK(&manager->lock);
manager->exiting = ISC_TRUE;
for (client = ISC_LIST_HEAD(manager->active);
client != NULL;
client = ISC_LIST_NEXT(client, link))
isc_task_shutdown(client->task);
for (client = ISC_LIST_HEAD(manager->inactive);
client != NULL;
client = ISC_LIST_NEXT(client, link))
isc_task_shutdown(client->task);
if (ISC_LIST_EMPTY(manager->active) &&
ISC_LIST_EMPTY(manager->inactive))
need_destroy = ISC_TRUE;
UNLOCK(&manager->lock);
if (need_destroy)
clientmgr_destroy(manager);
*managerp = NULL;
}
isc_result_t
ns_clientmgr_createclients(ns_clientmgr_t *manager, unsigned int n,
ns_interface_t *ifp, isc_boolean_t tcp)
{
isc_result_t result = ISC_R_SUCCESS;
unsigned int i;
ns_client_t *client;
REQUIRE(VALID_MANAGER(manager));
REQUIRE(n > 0);
MTRACE("createclients");
/*
* We MUST lock the manager lock for the entire client creation
* process. If we didn't do this, then a client could get a
* shutdown event and disappear out from under us.
*/
LOCK(&manager->lock);
for (i = 0; i < n; i++) {
/*
* Allocate a client. First try to get a recycled one;
* if that fails, make a new one.
*/
client = ISC_LIST_HEAD(manager->inactive);
if (client != NULL) {
MTRACE("recycle");
ISC_LIST_UNLINK(manager->inactive, client, link);
client->list = NULL;
} else {
MTRACE("create new");
result = client_create(manager, &client);
if (result != ISC_R_SUCCESS)
break;
}
client->state = NS_CLIENTSTATE_READY;
ns_interface_attach(ifp, &client->interface);
if (tcp) {
client->attributes |= NS_CLIENTATTR_TCP;
isc_socket_attach(ifp->tcpsocket,
&client->tcplistener);
client_accept(client);
} else {
dns_dispatch_attach(ifp->udpdispatch,
&client->dispatch);
result = dns_dispatch_addrequest(client->dispatch,
client->task,
client_request,
client,
&client->dispentry);
if (result != ISC_R_SUCCESS) {
isc_log_write(dns_lctx,
DNS_LOGCATEGORY_SECURITY,
NS_LOGMODULE_CLIENT,
ISC_LOG_DEBUG(3),
"dns_dispatch_addrequest() "
"failed: %s",
isc_result_totext(result));
isc_task_shutdown(client->task);
break;
}
}
client->manager = manager;
ISC_LIST_APPEND(manager->active, client, link);
client->list = &manager->active;
}
if (i != 0) {
/*
* We managed to create at least one client, so we
* declare victory.
*/
result = ISC_R_SUCCESS;
}
UNLOCK(&manager->lock);
return (result);
}
isc_sockaddr_t *
ns_client_getsockaddr(ns_client_t *client) {
return (&client->peeraddr);
}
isc_result_t
ns_client_checkacl(ns_client_t *client,
const char *opname, dns_acl_t *acl,
isc_boolean_t default_allow)
{
isc_result_t result;
int match;
isc_netaddr_t netaddr;
if (acl == NULL) {
if (default_allow)
goto allow;
else
goto deny;
}
isc_netaddr_fromsockaddr(&netaddr, &client->peeraddr);
result = dns_acl_match(&netaddr, client->signer, acl,
&ns_g_server->aclenv,
&match, NULL);
if (result != DNS_R_SUCCESS)
goto deny; /* Internal error, already logged. */
if (match > 0)
goto allow;
goto deny; /* Negative match or no match. */
allow:
isc_log_write(dns_lctx, DNS_LOGCATEGORY_SECURITY,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(3),
"%s approved", opname);
return (DNS_R_SUCCESS);
deny:
isc_log_write(dns_lctx, DNS_LOGCATEGORY_SECURITY,
NS_LOGMODULE_CLIENT, ISC_LOG_ERROR,
"%s denied", opname);
return (DNS_R_REFUSED);
}