#include <config.h>
#include <isc/formatcheck.h>
#include <isc/mutex.h>
#include <isc/once.h>
#include <isc/platform.h>
#include <isc/print.h>
#include <isc/stdio.h>
#include <isc/string.h>
#include <isc/task.h>
#include <isc/timer.h>
#include <isc/util.h>
#include <dns/db.h>
#include <dns/dispatch.h>
#include <dns/events.h>
#include <dns/message.h>
#include <dns/peer.h>
#include <dns/rcode.h>
#include <dns/rdata.h>
#include <dns/rdataclass.h>
#include <dns/rdatalist.h>
#include <dns/rdataset.h>
#include <dns/resolver.h>
#include <dns/tsig.h>
#include <dns/view.h>
#include <dns/zone.h>
#include <named/interfacemgr.h>
#include <named/log.h>
#include <named/notify.h>
#include <named/server.h>
#include <named/update.h>
#define NS_CLIENT_TRACE
#ifdef NS_CLIENT_TRACE
#define CTRACE(m) ns_client_log(client, \
NS_LOGCATEGORY_CLIENT, \
NS_LOGMODULE_CLIENT, \
ISC_LOG_DEBUG(3), \
"%s", (m))
#define MTRACE(m) isc_log_write(ns_g_lctx, \
NS_LOGCATEGORY_GENERAL, \
NS_LOGMODULE_CLIENT, \
ISC_LOG_DEBUG(3), \
"clientmgr @%p: %s", manager, (m))
#else
#define CTRACE(m) ((void)(m))
#define MTRACE(m) ((void)(m))
#endif
#define TCP_CLIENT(c) (((c)->attributes & NS_CLIENTATTR_TCP) != 0)
#define TCP_BUFFER_SIZE (65535 + 2)
#define SEND_BUFFER_SIZE 4096
#define RECV_BUFFER_SIZE 4096
#ifdef ISC_PLATFORM_USETHREADS
#define NMCTXS 100
#else
#define NMCTXS 0
#endif
struct ns_clientmgr {
unsigned int magic;
isc_mem_t * mctx;
isc_taskmgr_t * taskmgr;
isc_timermgr_t * timermgr;
isc_mutex_t lock;
isc_boolean_t exiting;
client_list_t active;
client_list_t recursing;
client_list_t inactive;
#if NMCTXS > 0
unsigned int nextmctx;
isc_mem_t * mctxpool[NMCTXS];
#endif
};
#define MANAGER_MAGIC ISC_MAGIC('N', 'S', 'C', 'm')
#define VALID_MANAGER(m) ISC_MAGIC_VALID(m, MANAGER_MAGIC)
#define NS_CLIENTSTATE_FREED 0
#define NS_CLIENTSTATE_INACTIVE 1
#define NS_CLIENTSTATE_READY 2
#define NS_CLIENTSTATE_READING 3
#define NS_CLIENTSTATE_WORKING 4
#define NS_CLIENTSTATE_MAX 9
#ifndef NS_CLIENT_DROPPORT
#define NS_CLIENT_DROPPORT 1
#endif
unsigned int ns_client_requests;
static void client_read(ns_client_t *client);
static void client_accept(ns_client_t *client);
static void client_udprecv(ns_client_t *client);
static void clientmgr_destroy(ns_clientmgr_t *manager);
static isc_boolean_t exit_check(ns_client_t *client);
static void ns_client_endrequest(ns_client_t *client);
static void ns_client_checkactive(ns_client_t *client);
static void client_start(isc_task_t *task, isc_event_t *event);
static void client_request(isc_task_t *task, isc_event_t *event);
static void ns_client_dumpmessage(ns_client_t *client, const char *reason);
void
ns_client_recursing(ns_client_t *client) {
REQUIRE(NS_CLIENT_VALID(client));
LOCK(&client->manager->lock);
ISC_LIST_UNLINK(*client->list, client, link);
ISC_LIST_APPEND(client->manager->recursing, client, link);
client->list = &client->manager->recursing;
UNLOCK(&client->manager->lock);
}
void
ns_client_killoldestquery(ns_client_t *client) {
ns_client_t *oldest;
REQUIRE(NS_CLIENT_VALID(client));
LOCK(&client->manager->lock);
oldest = ISC_LIST_HEAD(client->manager->recursing);
if (oldest != NULL) {
ns_query_cancel(oldest);
ISC_LIST_UNLINK(*oldest->list, oldest, link);
ISC_LIST_APPEND(client->manager->active, oldest, link);
oldest->list = &client->manager->active;
}
UNLOCK(&client->manager->lock);
}
void
ns_client_settimeout(ns_client_t *client, unsigned int seconds) {
isc_result_t result;
isc_interval_t interval;
isc_interval_set(&interval, seconds, 0);
result = isc_timer_reset(client->timer, isc_timertype_once, NULL,
&interval, ISC_FALSE);
client->timerset = ISC_TRUE;
if (result != ISC_R_SUCCESS) {
ns_client_log(client, NS_LOGCATEGORY_CLIENT,
NS_LOGMODULE_CLIENT, ISC_LOG_ERROR,
"setting timeout: %s",
isc_result_totext(result));
}
}
static isc_boolean_t
exit_check(ns_client_t *client) {
ns_clientmgr_t *locked_manager = NULL;
ns_clientmgr_t *destroy_manager = NULL;
REQUIRE(NS_CLIENT_VALID(client));
if (client->state <= client->newstate)
return (ISC_FALSE);
INSIST(client->newstate < NS_CLIENTSTATE_WORKING);
if (client->nupdates == 0 &&
client->newstate == NS_CLIENTSTATE_FREED && client->view != NULL)
dns_view_detach(&client->view);
if (client->state == NS_CLIENTSTATE_WORKING) {
INSIST(client->newstate <= NS_CLIENTSTATE_READING);
if (client->nupdates > 0)
return (ISC_TRUE);
if (client->nsends > 0) {
isc_socket_t *socket;
if (TCP_CLIENT(client))
socket = client->tcpsocket;
else
socket = client->udpsocket;
isc_socket_cancel(socket, client->task,
ISC_SOCKCANCEL_SEND);
}
if (! (client->nsends == 0 && client->nrecvs == 0 &&
client->references == 0))
{
return (ISC_TRUE);
}
LOCK(&client->manager->lock);
if (client->list == &client->manager->recursing) {
ISC_LIST_UNLINK(*client->list, client, link);
ISC_LIST_APPEND(client->manager->active, client, link);
client->list = &client->manager->active;
}
UNLOCK(&client->manager->lock);
ns_client_endrequest(client);
client->state = NS_CLIENTSTATE_READING;
INSIST(client->recursionquota == NULL);
if (NS_CLIENTSTATE_READING == client->newstate) {
client_read(client);
client->newstate = NS_CLIENTSTATE_MAX;
return (ISC_TRUE);
}
}
if (client->state == NS_CLIENTSTATE_READING) {
INSIST(client->recursionquota == NULL);
INSIST(client->newstate <= NS_CLIENTSTATE_READY);
if (client->nreads > 0)
dns_tcpmsg_cancelread(&client->tcpmsg);
if (! client->nreads == 0) {
return (ISC_TRUE);
}
if (client->tcpmsg_valid) {
dns_tcpmsg_invalidate(&client->tcpmsg);
client->tcpmsg_valid = ISC_FALSE;
}
if (client->tcpsocket != NULL) {
CTRACE("closetcp");
isc_socket_detach(&client->tcpsocket);
}
if (client->tcpquota != NULL)
isc_quota_detach(&client->tcpquota);
if (client->timerset) {
(void)isc_timer_reset(client->timer,
isc_timertype_inactive,
NULL, NULL, ISC_TRUE);
client->timerset = ISC_FALSE;
}
client->peeraddr_valid = ISC_FALSE;
client->state = NS_CLIENTSTATE_READY;
INSIST(client->recursionquota == NULL);
ns_client_checkactive(client);
if (NS_CLIENTSTATE_READY == client->newstate) {
if (TCP_CLIENT(client)) {
client_accept(client);
} else
client_udprecv(client);
client->newstate = NS_CLIENTSTATE_MAX;
return (ISC_TRUE);
}
}
if (client->state == NS_CLIENTSTATE_READY) {
INSIST(client->newstate <= NS_CLIENTSTATE_INACTIVE);
if (client->naccepts > 0)
isc_socket_cancel(client->tcplistener, client->task,
ISC_SOCKCANCEL_ACCEPT);
if (! (client->naccepts == 0)) {
return (ISC_TRUE);
}
if (client->nrecvs > 0)
isc_socket_cancel(client->udpsocket, client->task,
ISC_SOCKCANCEL_RECV);
if (! (client->nrecvs == 0)) {
return (ISC_TRUE);
}
if (client->nctls > 0) {
return (ISC_TRUE);
}
if (client->interface)
ns_interface_detach(&client->interface);
INSIST(client->naccepts == 0);
INSIST(client->recursionquota == NULL);
if (client->tcplistener != NULL)
isc_socket_detach(&client->tcplistener);
if (client->udpsocket != NULL)
isc_socket_detach(&client->udpsocket);
if (client->dispatch != NULL)
dns_dispatch_detach(&client->dispatch);
client->attributes = 0;
client->mortal = ISC_FALSE;
LOCK(&client->manager->lock);
locked_manager = client->manager;
ISC_LIST_UNLINK(*client->list, client, link);
ISC_LIST_APPEND(client->manager->inactive, client, link);
client->list = &client->manager->inactive;
client->state = NS_CLIENTSTATE_INACTIVE;
INSIST(client->recursionquota == NULL);
if (client->state == client->newstate) {
client->newstate = NS_CLIENTSTATE_MAX;
goto unlock;
}
}
if (client->state == NS_CLIENTSTATE_INACTIVE) {
INSIST(client->newstate == NS_CLIENTSTATE_FREED);
REQUIRE(client->state == NS_CLIENTSTATE_INACTIVE);
INSIST(client->recursionquota == NULL);
ns_query_free(client);
isc_mem_put(client->mctx, client->recvbuf, RECV_BUFFER_SIZE);
isc_event_free((isc_event_t **)&client->sendevent);
isc_event_free((isc_event_t **)&client->recvevent);
isc_timer_detach(&client->timer);
if (client->tcpbuf != NULL)
isc_mem_put(client->mctx, client->tcpbuf, TCP_BUFFER_SIZE);
if (client->opt != NULL) {
INSIST(dns_rdataset_isassociated(client->opt));
dns_rdataset_disassociate(client->opt);
dns_message_puttemprdataset(client->message, &client->opt);
}
dns_message_destroy(&client->message);
if (client->manager != NULL) {
ns_clientmgr_t *manager = client->manager;
if (locked_manager == NULL) {
LOCK(&manager->lock);
locked_manager = manager;
}
ISC_LIST_UNLINK(*client->list, client, link);
client->list = NULL;
if (manager->exiting &&
ISC_LIST_EMPTY(manager->active) &&
ISC_LIST_EMPTY(manager->inactive) &&
ISC_LIST_EMPTY(manager->recursing))
destroy_manager = manager;
}
if (client->task != NULL)
isc_task_detach(&client->task);
CTRACE("free");
client->magic = 0;
isc_mem_putanddetach(&client->mctx, client, sizeof(*client));
goto unlock;
}
unlock:
if (locked_manager != NULL) {
UNLOCK(&locked_manager->lock);
locked_manager = NULL;
}
if (destroy_manager != NULL)
clientmgr_destroy(destroy_manager);
return (ISC_TRUE);
}
static void
client_start(isc_task_t *task, isc_event_t *event) {
ns_client_t *client = (ns_client_t *) event->ev_arg;
INSIST(task == client->task);
UNUSED(task);
INSIST(client->nctls == 1);
client->nctls--;
if (exit_check(client))
return;
if (TCP_CLIENT(client)) {
client_accept(client);
} else {
client_udprecv(client);
}
}
static void
client_shutdown(isc_task_t *task, isc_event_t *event) {
ns_client_t *client;
REQUIRE(event != NULL);
REQUIRE(event->ev_type == ISC_TASKEVENT_SHUTDOWN);
client = event->ev_arg;
REQUIRE(NS_CLIENT_VALID(client));
REQUIRE(task == client->task);
UNUSED(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->nrecvs == 0);
INSIST(client->nupdates == 0);
INSIST(client->state == NS_CLIENTSTATE_WORKING);
CTRACE("endrequest");
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;
client->extflags = 0;
client->ednsversion = -1;
dns_message_reset(client->message, DNS_MESSAGE_INTENTPARSE);
if (client->recursionquota != NULL)
isc_quota_detach(&client->recursionquota);
client->attributes &= NS_CLIENTATTR_TCP;
}
static void
ns_client_checkactive(ns_client_t *client) {
if (client->mortal) {
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 {
}
if (! need_another_client) {
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 ||
client->state == NS_CLIENTSTATE_READING);
CTRACE("next");
if (result != ISC_R_SUCCESS)
ns_client_log(client, DNS_LOGCATEGORY_SECURITY,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(3),
"request failed: %s", isc_result_totext(result));
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->ev_type == ISC_SOCKEVENT_SENDDONE);
client = sevent->ev_arg;
REQUIRE(NS_CLIENT_VALID(client));
REQUIRE(task == client->task);
REQUIRE(sevent == client->sendevent);
UNUSED(task);
CTRACE("senddone");
if (sevent->result != ISC_R_SUCCESS)
ns_client_log(client, NS_LOGCATEGORY_CLIENT,
NS_LOGMODULE_CLIENT, ISC_LOG_WARNING,
"error sending response: %s",
isc_result_totext(sevent->result));
INSIST(client->nsends > 0);
client->nsends--;
if (client->tcpbuf != NULL) {
INSIST(TCP_CLIENT(client));
isc_mem_put(client->mctx, client->tcpbuf, TCP_BUFFER_SIZE);
client->tcpbuf = NULL;
}
if (exit_check(client))
return;
ns_client_next(client, ISC_R_SUCCESS);
}
static isc_result_t
client_allocsendbuf(ns_client_t *client, isc_buffer_t *buffer,
isc_buffer_t *tcpbuffer, isc_uint32_t length,
unsigned char *sendbuf, unsigned char **datap)
{
unsigned char *data;
isc_uint32_t bufsize;
isc_result_t result;
INSIST(datap != NULL);
INSIST((tcpbuffer == NULL && length != 0) ||
(tcpbuffer != NULL && length == 0));
if (TCP_CLIENT(client)) {
INSIST(client->tcpbuf == NULL);
if (length + 2 > TCP_BUFFER_SIZE) {
result = ISC_R_NOSPACE;
goto done;
}
client->tcpbuf = isc_mem_get(client->mctx, TCP_BUFFER_SIZE);
if (client->tcpbuf == NULL) {
result = ISC_R_NOMEMORY;
goto done;
}
data = client->tcpbuf;
if (tcpbuffer != NULL) {
isc_buffer_init(tcpbuffer, data, TCP_BUFFER_SIZE);
isc_buffer_init(buffer, data + 2, TCP_BUFFER_SIZE - 2);
} else {
isc_buffer_init(buffer, data, TCP_BUFFER_SIZE);
INSIST(length <= 0xffff);
isc_buffer_putuint16(buffer, (isc_uint16_t)length);
}
} else {
data = sendbuf;
if (client->udpsize < SEND_BUFFER_SIZE)
bufsize = client->udpsize;
else
bufsize = SEND_BUFFER_SIZE;
if (length > bufsize) {
result = ISC_R_NOSPACE;
goto done;
}
isc_buffer_init(buffer, data, bufsize);
}
*datap = data;
result = ISC_R_SUCCESS;
done:
return (result);
}
static isc_result_t
client_sendpkg(ns_client_t *client, isc_buffer_t *buffer) {
struct in6_pktinfo *pktinfo;
isc_result_t result;
isc_region_t r;
isc_sockaddr_t *address;
isc_socket_t *socket;
isc_netaddr_t netaddr;
int match;
unsigned int sockflags = ISC_SOCKFLAG_IMMEDIATE;
if (TCP_CLIENT(client)) {
socket = client->tcpsocket;
address = NULL;
} else {
socket = client->udpsocket;
address = &client->peeraddr;
isc_netaddr_fromsockaddr(&netaddr, &client->peeraddr);
if (ns_g_server->blackholeacl != NULL &&
dns_acl_match(&netaddr, NULL,
ns_g_server->blackholeacl,
&ns_g_server->aclenv,
&match, NULL) == ISC_R_SUCCESS &&
match > 0)
return (DNS_R_BLACKHOLED);
sockflags |= ISC_SOCKFLAG_NORETRY;
}
if ((client->attributes & NS_CLIENTATTR_PKTINFO) != 0 &&
(client->attributes & NS_CLIENTATTR_MULTICAST) == 0)
pktinfo = &client->pktinfo;
else
pktinfo = NULL;
isc_buffer_usedregion(buffer, &r);
CTRACE("sendto");
result = isc_socket_sendto2(socket, &r, client->task,
address, pktinfo,
client->sendevent, sockflags);
if (result == ISC_R_SUCCESS || result == ISC_R_INPROGRESS) {
client->nsends++;
if (result == ISC_R_SUCCESS)
client_senddone(client->task,
(isc_event_t *)client->sendevent);
result = ISC_R_SUCCESS;
}
return (result);
}
void
ns_client_sendraw(ns_client_t *client, dns_message_t *message) {
isc_result_t result;
unsigned char *data;
isc_buffer_t buffer;
isc_region_t r;
isc_region_t *mr;
unsigned char sendbuf[SEND_BUFFER_SIZE];
REQUIRE(NS_CLIENT_VALID(client));
CTRACE("sendraw");
mr = dns_message_getrawmessage(message);
if (mr == NULL) {
result = ISC_R_UNEXPECTEDEND;
goto done;
}
result = client_allocsendbuf(client, &buffer, NULL, mr->length,
sendbuf, &data);
if (result != ISC_R_SUCCESS)
goto done;
isc_buffer_availableregion(&buffer, &r);
result = isc_buffer_copyregion(&buffer, mr);
if (result != ISC_R_SUCCESS)
goto done;
r.base[0] = (client->message->id >> 8) & 0xff;
r.base[1] = client->message->id & 0xff;
result = client_sendpkg(client, &buffer);
if (result == ISC_R_SUCCESS)
return;
done:
if (client->tcpbuf != NULL) {
isc_mem_put(client->mctx, client->tcpbuf, TCP_BUFFER_SIZE);
client->tcpbuf = NULL;
}
ns_client_next(client, result);
}
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;
dns_compress_t cctx;
isc_boolean_t cleanup_cctx = ISC_FALSE;
unsigned char sendbuf[SEND_BUFFER_SIZE];
unsigned int dnssec_opts;
unsigned int preferred_glue;
REQUIRE(NS_CLIENT_VALID(client));
CTRACE("send");
if ((client->attributes & NS_CLIENTATTR_RA) != 0)
client->message->flags |= DNS_MESSAGEFLAG_RA;
if ((client->attributes & NS_CLIENTATTR_WANTDNSSEC) != 0)
dnssec_opts = 0;
else
dnssec_opts = DNS_MESSAGERENDER_OMITDNSSEC;
preferred_glue = 0;
if (client->view != NULL) {
if (client->view->preferred_glue == dns_rdatatype_a)
preferred_glue = DNS_MESSAGERENDER_PREFER_A;
else if (client->view->preferred_glue == dns_rdatatype_aaaa)
preferred_glue = DNS_MESSAGERENDER_PREFER_AAAA;
}
result = client_allocsendbuf(client, &buffer, &tcpbuffer, 0,
sendbuf, &data);
if (result != ISC_R_SUCCESS)
goto done;
result = dns_compress_init(&cctx, -1, client->mctx);
if (result != ISC_R_SUCCESS)
goto done;
cleanup_cctx = ISC_TRUE;
result = dns_message_renderbegin(client->message, &cctx, &buffer);
if (result != ISC_R_SUCCESS)
goto done;
if (client->opt != NULL) {
result = dns_message_setopt(client->message, client->opt);
client->opt = NULL;
if (result != ISC_R_SUCCESS)
goto done;
}
result = dns_message_rendersection(client->message,
DNS_SECTION_QUESTION, 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_ANSWER,
DNS_MESSAGERENDER_PARTIAL |
dnssec_opts);
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,
DNS_MESSAGERENDER_PARTIAL |
dnssec_opts);
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,
preferred_glue | dnssec_opts);
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 (cleanup_cctx) {
dns_compress_invalidate(&cctx);
cleanup_cctx = ISC_FALSE;
}
if (TCP_CLIENT(client)) {
isc_buffer_usedregion(&buffer, &r);
isc_buffer_putuint16(&tcpbuffer, (isc_uint16_t) r.length);
isc_buffer_add(&tcpbuffer, r.length);
result = client_sendpkg(client, &tcpbuffer);
} else
result = client_sendpkg(client, &buffer);
if (result == ISC_R_SUCCESS)
return;
done:
if (client->tcpbuf != NULL) {
isc_mem_put(client->mctx, client->tcpbuf, TCP_BUFFER_SIZE);
client->tcpbuf = NULL;
}
if (cleanup_cctx)
dns_compress_invalidate(&cctx);
ns_client_next(client, result);
}
#if NS_CLIENT_DROPPORT
#define DROPPORT_NO 0
#define DROPPORT_REQUEST 1
#define DROPPORT_RESPONSE 2
static int
ns_client_dropport(in_port_t port) {
switch (port) {
case 7:
case 13:
case 19:
case 37:
return (DROPPORT_REQUEST);
case 464:
return (DROPPORT_RESPONSE);
}
return (DROPPORT_NO);
}
#endif
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);
#if NS_CLIENT_DROPPORT
if (rcode == dns_rcode_formerr &&
ns_client_dropport(isc_sockaddr_getport(&client->peeraddr)) !=
DROPPORT_NO) {
char buf[64];
isc_buffer_t b;
isc_buffer_init(&b, buf, sizeof(buf) - 1);
if (dns_rcode_totext(rcode, &b) != ISC_R_SUCCESS)
isc_buffer_putstr(&b, "UNKNOWN RCODE");
ns_client_log(client, DNS_LOGCATEGORY_SECURITY,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(10),
"dropped error (%.*s) response: suspicious port",
(int)isc_buffer_usedlength(&b), buf);
ns_client_next(client, ISC_R_SUCCESS);
return;
}
#endif
message->flags &= ~DNS_MESSAGEFLAG_QR;
message->flags &= ~(DNS_MESSAGEFLAG_AA | DNS_MESSAGEFLAG_AD);
result = dns_message_reply(message, ISC_TRUE);
if (result != ISC_R_SUCCESS) {
result = dns_message_reply(message, ISC_FALSE);
if (result != ISC_R_SUCCESS) {
ns_client_next(client, result);
return;
}
}
message->rcode = rcode;
if (rcode == dns_rcode_formerr) {
if (isc_sockaddr_equal(&client->peeraddr,
&client->formerrcache.addr) &&
message->id == client->formerrcache.id &&
client->requesttime - client->formerrcache.time < 2) {
ns_client_log(client, NS_LOGCATEGORY_CLIENT,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(1),
"possible error packet loop, "
"FORMERR dropped");
ns_client_next(client, result);
return;
}
client->formerrcache.addr = client->peeraddr;
client->formerrcache.time = client->requesttime;
client->formerrcache.id = message->id;
}
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;
dns_view_t *view;
dns_resolver_t *resolver;
isc_uint16_t udpsize;
REQUIRE(client->opt == NULL);
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;
view = client->view;
resolver = (view != NULL) ? view->resolver : NULL;
if (resolver != NULL)
udpsize = dns_resolver_getudpsize(resolver);
else
udpsize = ns_g_udpsize;
rdatalist->rdclass = udpsize;
rdatalist->ttl = (client->extflags & DNS_MESSAGEEXTFLAG_REPLYPRESERVE);
rdata->data = NULL;
rdata->length = 0;
rdata->rdclass = rdatalist->rdclass;
rdata->type = rdatalist->type;
rdata->flags = 0;
ISC_LIST_INIT(rdatalist->rdata);
ISC_LIST_APPEND(rdatalist->rdata, rdata, link);
RUNTIME_CHECK(dns_rdatalist_tordataset(rdatalist, rdataset)
== ISC_R_SUCCESS);
client->opt = rdataset;
return (ISC_R_SUCCESS);
}
static inline isc_boolean_t
allowed(isc_netaddr_t *addr, dns_name_t *signer, dns_acl_t *acl) {
int match;
isc_result_t result;
if (acl == NULL)
return (ISC_TRUE);
result = dns_acl_match(addr, signer, acl, &ns_g_server->aclenv,
&match, NULL);
if (result == ISC_R_SUCCESS && match > 0)
return (ISC_TRUE);
return (ISC_FALSE);
}
isc_boolean_t
ns_client_isself(dns_view_t *myview, dns_tsigkey_t *mykey,
isc_sockaddr_t *srcaddr, isc_sockaddr_t *dstaddr,
dns_rdataclass_t rdclass, void *arg)
{
dns_view_t *view;
dns_tsigkey_t *key;
isc_netaddr_t netsrc;
isc_netaddr_t netdst;
UNUSED(arg);
if (!ns_interfacemgr_listeningon(ns_g_server->interfacemgr, dstaddr))
return (ISC_FALSE);
isc_netaddr_fromsockaddr(&netsrc, srcaddr);
isc_netaddr_fromsockaddr(&netdst, dstaddr);
for (view = ISC_LIST_HEAD(ns_g_server->viewlist);
view != NULL;
view = ISC_LIST_NEXT(view, link)) {
dns_name_t *tsig = NULL;
if (view->matchrecursiveonly)
continue;
if (rdclass != view->rdclass)
continue;
if (mykey != NULL) {
isc_boolean_t match;
isc_result_t result;
tsig = &mykey->name;
result = dns_view_gettsig(view, tsig, &key);
if (result != ISC_R_SUCCESS)
continue;
match = dst_key_compare(mykey->key, key->key);
dns_tsigkey_detach(&key);
if (!match)
continue;
}
if (allowed(&netsrc, tsig, view->matchclients) &&
allowed(&netdst, tsig, view->matchdestinations))
break;
}
return (ISC_TF(view == myview));
}
static void
client_request(isc_task_t *task, isc_event_t *event) {
ns_client_t *client;
isc_socketevent_t *sevent;
isc_result_t result;
isc_result_t sigresult = ISC_R_SUCCESS;
isc_buffer_t *buffer;
isc_buffer_t tbuffer;
dns_view_t *view;
dns_rdataset_t *opt;
isc_boolean_t ra;
isc_netaddr_t netaddr;
isc_netaddr_t destaddr;
int match;
dns_messageid_t id;
unsigned int flags;
isc_boolean_t notimp;
REQUIRE(event != NULL);
client = event->ev_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);
ns_client_requests++;
if (event->ev_type == ISC_SOCKEVENT_RECVDONE) {
INSIST(!TCP_CLIENT(client));
sevent = (isc_socketevent_t *)event;
REQUIRE(sevent == client->recvevent);
isc_buffer_init(&tbuffer, sevent->region.base, sevent->n);
isc_buffer_add(&tbuffer, sevent->n);
buffer = &tbuffer;
result = sevent->result;
if (result == ISC_R_SUCCESS) {
client->peeraddr = sevent->address;
client->peeraddr_valid = ISC_TRUE;
}
if ((sevent->attributes & ISC_SOCKEVENTATTR_PKTINFO) != 0) {
client->attributes |= NS_CLIENTATTR_PKTINFO;
client->pktinfo = sevent->pktinfo;
}
if ((sevent->attributes & ISC_SOCKEVENTATTR_MULTICAST) != 0)
client->attributes |= NS_CLIENTATTR_MULTICAST;
client->nrecvs--;
} else {
INSIST(TCP_CLIENT(client));
REQUIRE(event->ev_type == DNS_EVENT_TCPMSG);
REQUIRE(event->ev_sender == &client->tcpmsg);
buffer = &client->tcpmsg.buffer;
result = client->tcpmsg.result;
INSIST(client->nreads == 1);
client->nreads--;
}
if (exit_check(client))
goto cleanup;
client->state = client->newstate = NS_CLIENTSTATE_WORKING;
isc_task_getcurrenttime(task, &client->requesttime);
client->now = client->requesttime;
if (result != ISC_R_SUCCESS) {
if (TCP_CLIENT(client)) {
ns_client_next(client, result);
} else {
if (result != ISC_R_CANCELED)
isc_log_write(ns_g_lctx, NS_LOGCATEGORY_CLIENT,
NS_LOGMODULE_CLIENT,
ISC_LOG_ERROR,
"UDP client handler shutting "
"down due to fatal receive "
"error: %s",
isc_result_totext(result));
isc_task_shutdown(client->task);
}
goto cleanup;
}
isc_netaddr_fromsockaddr(&netaddr, &client->peeraddr);
#if NS_CLIENT_DROPPORT
if (ns_client_dropport(isc_sockaddr_getport(&client->peeraddr)) ==
DROPPORT_REQUEST) {
ns_client_log(client, DNS_LOGCATEGORY_SECURITY,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(10),
"dropped request: suspicious port");
ns_client_next(client, ISC_R_SUCCESS);
goto cleanup;
}
#endif
ns_client_log(client, NS_LOGCATEGORY_CLIENT,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(3),
"%s request",
TCP_CLIENT(client) ? "TCP" : "UDP");
if (!TCP_CLIENT(client)) {
if (ns_g_server->blackholeacl != NULL &&
dns_acl_match(&netaddr, NULL, ns_g_server->blackholeacl,
&ns_g_server->aclenv,
&match, NULL) == ISC_R_SUCCESS &&
match > 0)
{
ns_client_log(client, DNS_LOGCATEGORY_SECURITY,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(10),
"blackholed UDP datagram");
ns_client_next(client, ISC_R_SUCCESS);
goto cleanup;
}
}
if ((client->attributes & NS_CLIENTATTR_MULTICAST) != 0) {
ns_client_log(client, NS_LOGCATEGORY_CLIENT,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(2),
"dropping multicast request");
ns_client_next(client, DNS_R_REFUSED);
goto cleanup;
}
result = dns_message_peekheader(buffer, &id, &flags);
if (result != ISC_R_SUCCESS) {
ns_client_next(client, result);
goto cleanup;
}
if ((flags & DNS_MESSAGEFLAG_QR) != 0) {
if (TCP_CLIENT(client)) {
CTRACE("unexpected response");
ns_client_next(client, DNS_R_FORMERR);
goto cleanup;
} else {
dns_dispatch_importrecv(client->dispatch, event);
ns_client_next(client, ISC_R_SUCCESS);
goto cleanup;
}
}
dns_dispatch_hash(&client->now, sizeof(client->now));
dns_dispatch_hash(isc_buffer_base(buffer),
isc_buffer_usedlength(buffer));
result = dns_message_parse(client->message, buffer, 0);
if (result != ISC_R_SUCCESS) {
ns_client_error(client, result);
goto cleanup;
}
switch (client->message->opcode) {
case dns_opcode_query:
case dns_opcode_update:
case dns_opcode_notify:
notimp = ISC_FALSE;
break;
case dns_opcode_iquery:
default:
notimp = ISC_TRUE;
break;
}
client->message->rcode = dns_rcode_noerror;
if ((client->attributes & NS_CLIENTATTR_MULTICAST) != 0)
client->message->flags &= ~DNS_MESSAGEFLAG_RD;
opt = dns_message_getopt(client->message);
if (opt != NULL) {
client->udpsize = opt->rdclass;
if (client->udpsize < 512)
client->udpsize = 512;
client->extflags = (isc_uint16_t)(opt->ttl & 0xFFFF);
client->ednsversion = (opt->ttl & 0x00FF0000) >> 16;
if (client->ednsversion > 0) {
result = client_addopt(client);
if (result == ISC_R_SUCCESS)
result = DNS_R_BADVERS;
ns_client_error(client, result);
goto cleanup;
}
result = client_addopt(client);
if (result != ISC_R_SUCCESS) {
ns_client_error(client, result);
goto cleanup;
}
}
if (client->message->rdclass == 0) {
ns_client_log(client, NS_LOGCATEGORY_CLIENT,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(1),
"message class could not be determined");
ns_client_dumpmessage(client,
"message class could not be determined");
ns_client_error(client, notimp ? DNS_R_NOTIMP : DNS_R_FORMERR);
goto cleanup;
}
if ((client->interface->flags & NS_INTERFACEFLAG_ANYADDR) == 0)
isc_netaddr_fromsockaddr(&destaddr, &client->interface->addr);
else {
result = ISC_R_FAILURE;
if (TCP_CLIENT(client)) {
isc_sockaddr_t destsockaddr;
result = isc_socket_getsockname(client->tcpsocket,
&destsockaddr);
if (result == ISC_R_SUCCESS)
isc_netaddr_fromsockaddr(&destaddr,
&destsockaddr);
}
if (result != ISC_R_SUCCESS &&
client->interface->addr.type.sa.sa_family == AF_INET6 &&
(client->attributes & NS_CLIENTATTR_PKTINFO) != 0) {
isc_uint32_t zone = 0;
if (IN6_IS_ADDR_LINKLOCAL(&client->pktinfo.ipi6_addr))
zone = (isc_uint32_t)client->pktinfo.ipi6_ifindex;
isc_netaddr_fromin6(&destaddr,
&client->pktinfo.ipi6_addr);
isc_netaddr_setzone(&destaddr, zone);
result = ISC_R_SUCCESS;
}
if (result != ISC_R_SUCCESS) {
UNEXPECTED_ERROR(__FILE__, __LINE__,
"failed to get request's "
"destination: %s",
isc_result_totext(result));
goto cleanup;
}
}
for (view = ISC_LIST_HEAD(ns_g_server->viewlist);
view != NULL;
view = ISC_LIST_NEXT(view, link)) {
if (client->message->rdclass == view->rdclass ||
client->message->rdclass == dns_rdataclass_any)
{
dns_name_t *tsig = NULL;
sigresult = dns_message_rechecksig(client->message,
view);
if (sigresult == ISC_R_SUCCESS)
tsig = client->message->tsigname;
if (allowed(&netaddr, tsig, view->matchclients) &&
allowed(&destaddr, tsig, view->matchdestinations) &&
!((client->message->flags & DNS_MESSAGEFLAG_RD)
== 0 && view->matchrecursiveonly))
{
dns_view_attach(view, &client->view);
break;
}
}
}
if (view == NULL) {
char classname[DNS_RDATACLASS_FORMATSIZE];
isc_buffer_t b;
isc_region_t *r;
dns_message_resetsig(client->message);
r = dns_message_getrawmessage(client->message);
isc_buffer_init(&b, r->base, r->length);
isc_buffer_add(&b, r->length);
(void)dns_tsig_verify(&b, client->message, NULL, NULL);
dns_rdataclass_format(client->message->rdclass, classname,
sizeof(classname));
ns_client_log(client, NS_LOGCATEGORY_CLIENT,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(1),
"no matching view in class '%s'", classname);
ns_client_dumpmessage(client, "no matching view in class");
ns_client_error(client, notimp ? DNS_R_NOTIMP : DNS_R_REFUSED);
goto cleanup;
}
ns_client_log(client, NS_LOGCATEGORY_CLIENT,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(5),
"using view '%s'", view->name);
client->signer = NULL;
dns_name_init(&client->signername, NULL);
result = dns_message_signer(client->message, &client->signername);
if (result == ISC_R_SUCCESS) {
ns_client_log(client, DNS_LOGCATEGORY_SECURITY,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(3),
"request has valid signature");
client->signer = &client->signername;
} else if (result == ISC_R_NOTFOUND) {
ns_client_log(client, DNS_LOGCATEGORY_SECURITY,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(3),
"request is not signed");
} else if (result == DNS_R_NOIDENTITY) {
ns_client_log(client, DNS_LOGCATEGORY_SECURITY,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(3),
"request is signed by a nonauthoritative key");
} else {
char tsigrcode[64];
isc_buffer_t b;
dns_name_t *name = NULL;
isc_buffer_init(&b, tsigrcode, sizeof(tsigrcode) - 1);
RUNTIME_CHECK(dns_tsigrcode_totext(client->message->tsigstatus,
&b) == ISC_R_SUCCESS);
tsigrcode[isc_buffer_usedlength(&b)] = '\0';
if (dns_message_gettsig(client->message, &name) != NULL) {
char namebuf[DNS_NAME_FORMATSIZE];
dns_name_format(name, namebuf, sizeof(namebuf));
ns_client_log(client, DNS_LOGCATEGORY_SECURITY,
NS_LOGMODULE_CLIENT, ISC_LOG_ERROR,
"request has invalid signature: "
"TSIG %s: %s (%s)", namebuf,
isc_result_totext(result), tsigrcode);
} else {
ns_client_log(client, DNS_LOGCATEGORY_SECURITY,
NS_LOGMODULE_CLIENT, ISC_LOG_ERROR,
"request has invalid signature: %s (%s)",
isc_result_totext(result), tsigrcode);
}
if (!(client->message->tsigstatus == dns_tsigerror_badkey &&
client->message->opcode == dns_opcode_update)) {
ns_client_error(client, sigresult);
goto cleanup;
}
}
ra = ISC_FALSE;
if (client->view->resolver != NULL &&
client->view->recursion == ISC_TRUE &&
ns_client_checkaclsilent(client, client->view->recursionacl,
ISC_TRUE) == ISC_R_SUCCESS &&
ns_client_checkaclsilent(client, client->view->queryacl,
ISC_TRUE) == ISC_R_SUCCESS)
ra = ISC_TRUE;
if (ra == ISC_TRUE)
client->attributes |= NS_CLIENTATTR_RA;
ns_client_log(client, DNS_LOGCATEGORY_SECURITY, NS_LOGMODULE_CLIENT,
ISC_LOG_DEBUG(3), ra ? "recursion available" :
"recursion not available");
if (client->udpsize > 512) {
dns_peer_t *peer = NULL;
isc_uint16_t udpsize = view->maxudp;
(void) dns_peerlist_peerbyaddr(view->peers, &netaddr, &peer);
if (peer != NULL)
dns_peer_getmaxudp(peer, &udpsize);
if (client->udpsize > udpsize)
client->udpsize = udpsize;
}
switch (client->message->opcode) {
case dns_opcode_query:
CTRACE("query");
ns_query_start(client);
break;
case dns_opcode_update:
CTRACE("update");
ns_client_settimeout(client, 60);
ns_update_start(client, sigresult);
break;
case dns_opcode_notify:
CTRACE("notify");
ns_client_settimeout(client, 60);
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:
return;
}
static void
client_timeout(isc_task_t *task, isc_event_t *event) {
ns_client_t *client;
REQUIRE(event != NULL);
REQUIRE(event->ev_type == ISC_TIMEREVENT_LIFE ||
event->ev_type == ISC_TIMEREVENT_IDLE);
client = event->ev_arg;
REQUIRE(NS_CLIENT_VALID(client));
REQUIRE(task == client->task);
REQUIRE(client->timer != NULL);
UNUSED(task);
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
get_clientmctx(ns_clientmgr_t *manager, isc_mem_t **mctxp) {
isc_mem_t *clientmctx;
#if NMCTXS > 0
isc_result_t result;
#endif
#if NMCTXS > 0
INSIST(manager->nextmctx < NMCTXS);
clientmctx = manager->mctxpool[manager->nextmctx];
if (clientmctx == NULL) {
result = isc_mem_create(0, 0, &clientmctx);
if (result != ISC_R_SUCCESS)
return (result);
manager->mctxpool[manager->nextmctx] = clientmctx;
manager->nextmctx++;
if (manager->nextmctx == NMCTXS)
manager->nextmctx = 0;
}
#else
clientmctx = manager->mctx;
#endif
isc_mem_attach(clientmctx, mctxp);
return (ISC_R_SUCCESS);
}
static isc_result_t
client_create(ns_clientmgr_t *manager, ns_client_t **clientp) {
ns_client_t *client;
isc_result_t result;
isc_mem_t *mctx = NULL;
REQUIRE(clientp != NULL && *clientp == NULL);
result = get_clientmctx(manager, &mctx);
if (result != ISC_R_SUCCESS)
return (result);
client = isc_mem_get(mctx, sizeof(*client));
if (client == NULL) {
isc_mem_detach(&mctx);
return (ISC_R_NOMEMORY);
}
client->mctx = mctx;
client->task = NULL;
result = isc_task_create(manager->taskmgr, 0, &client->task);
if (result != ISC_R_SUCCESS)
goto cleanup_client;
isc_task_setname(client->task, "client", client);
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->timerset = ISC_FALSE;
client->message = NULL;
result = dns_message_create(client->mctx, DNS_MESSAGE_INTENTPARSE,
&client->message);
if (result != ISC_R_SUCCESS)
goto cleanup_timer;
client->sendevent = (isc_socketevent_t *)
isc_event_allocate(client->mctx, client,
ISC_SOCKEVENT_SENDDONE,
client_senddone, client,
sizeof(isc_socketevent_t));
if (client->sendevent == NULL) {
result = ISC_R_NOMEMORY;
goto cleanup_message;
}
client->recvbuf = isc_mem_get(client->mctx, RECV_BUFFER_SIZE);
if (client->recvbuf == NULL) {
result = ISC_R_NOMEMORY;
goto cleanup_sendevent;
}
client->recvevent = (isc_socketevent_t *)
isc_event_allocate(client->mctx, client,
ISC_SOCKEVENT_RECVDONE,
client_request, client,
sizeof(isc_socketevent_t));
if (client->recvevent == NULL) {
result = ISC_R_NOMEMORY;
goto cleanup_recvbuf;
}
client->magic = NS_CLIENT_MAGIC;
client->manager = NULL;
client->state = NS_CLIENTSTATE_INACTIVE;
client->newstate = NS_CLIENTSTATE_MAX;
client->naccepts = 0;
client->nreads = 0;
client->nsends = 0;
client->nrecvs = 0;
client->nupdates = 0;
client->nctls = 0;
client->references = 0;
client->attributes = 0;
client->view = NULL;
client->dispatch = NULL;
client->udpsocket = NULL;
client->tcplistener = NULL;
client->tcpsocket = NULL;
client->tcpmsg_valid = ISC_FALSE;
client->tcpbuf = NULL;
client->opt = NULL;
client->udpsize = 512;
client->extflags = 0;
client->ednsversion = -1;
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;
client->peeraddr_valid = ISC_FALSE;
ISC_EVENT_INIT(&client->ctlevent, sizeof(client->ctlevent), 0, NULL,
NS_EVENT_CLIENTCONTROL, client_start, client, client,
NULL, NULL);
isc_sockaddr_any(&client->formerrcache.addr);
client->formerrcache.time = 0;
client->formerrcache.id = 0;
ISC_LINK_INIT(client, link);
client->list = NULL;
result = ns_query_init(client);
if (result != ISC_R_SUCCESS)
goto cleanup_recvevent;
result = isc_task_onshutdown(client->task, client_shutdown, client);
if (result != ISC_R_SUCCESS)
goto cleanup_query;
CTRACE("create");
*clientp = client;
return (ISC_R_SUCCESS);
cleanup_query:
ns_query_free(client);
cleanup_recvevent:
isc_event_free((isc_event_t **)&client->recvevent);
cleanup_recvbuf:
isc_mem_put(client->mctx, client->recvbuf, RECV_BUFFER_SIZE);
cleanup_sendevent:
isc_event_free((isc_event_t **)&client->sendevent);
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_putanddetach(&client->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;
ns_client_settimeout(client, 30);
client->state = client->newstate = NS_CLIENTSTATE_READING;
INSIST(client->nreads == 0);
INSIST(client->recursionquota == NULL);
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->ev_arg;
isc_socket_newconnev_t *nevent = (isc_socket_newconnev_t *)event;
isc_result_t result;
REQUIRE(event->ev_type == ISC_SOCKEVENT_NEWCONN);
REQUIRE(NS_CLIENT_VALID(client));
REQUIRE(client->task == task);
UNUSED(task);
INSIST(client->state == NS_CLIENTSTATE_READY);
INSIST(client->naccepts == 1);
client->naccepts--;
LOCK(&client->interface->lock);
INSIST(client->interface->ntcpcurrent > 0);
client->interface->ntcpcurrent--;
UNLOCK(&client->interface->lock);
if (nevent->result == ISC_R_SUCCESS) {
client->tcpsocket = nevent->newsocket;
client->state = NS_CLIENTSTATE_READING;
INSIST(client->recursionquota == NULL);
(void)isc_socket_getpeername(client->tcpsocket,
&client->peeraddr);
client->peeraddr_valid = ISC_TRUE;
ns_client_log(client, NS_LOGCATEGORY_CLIENT,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(3),
"new TCP connection");
} else {
ns_client_log(client, NS_LOGCATEGORY_CLIENT,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(3),
"accept failed: %s",
isc_result_totext(nevent->result));
}
if (exit_check(client))
goto freeevent;
if (nevent->result == ISC_R_SUCCESS) {
int match;
isc_netaddr_t netaddr;
isc_netaddr_fromsockaddr(&netaddr, &client->peeraddr);
if (ns_g_server->blackholeacl != NULL &&
dns_acl_match(&netaddr, NULL,
ns_g_server->blackholeacl,
&ns_g_server->aclenv,
&match, NULL) == ISC_R_SUCCESS &&
match > 0)
{
ns_client_log(client, DNS_LOGCATEGORY_SECURITY,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(10),
"blackholed connection attempt");
client->newstate = NS_CLIENTSTATE_READY;
(void)exit_check(client);
goto freeevent;
}
INSIST(client->tcpmsg_valid == ISC_FALSE);
dns_tcpmsg_init(client->mctx, client->tcpsocket,
&client->tcpmsg);
client->tcpmsg_valid = ISC_TRUE;
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) {
ns_client_log(client, 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));
return;
}
INSIST(client->naccepts == 0);
client->naccepts++;
LOCK(&client->interface->lock);
client->interface->ntcpcurrent++;
UNLOCK(&client->interface->lock);
}
static void
client_udprecv(ns_client_t *client) {
isc_result_t result;
isc_region_t r;
CTRACE("udprecv");
r.base = client->recvbuf;
r.length = RECV_BUFFER_SIZE;
result = isc_socket_recv2(client->udpsocket, &r, 1,
client->task, client->recvevent, 0);
if (result != ISC_R_SUCCESS) {
UNEXPECTED_ERROR(__FILE__, __LINE__,
"isc_socket_recv2() failed: %s",
isc_result_totext(result));
return;
}
INSIST(client->nrecvs == 0);
client->nrecvs++;
}
void
ns_client_attach(ns_client_t *source, ns_client_t **targetp) {
REQUIRE(NS_CLIENT_VALID(source));
REQUIRE(targetp != NULL && *targetp == NULL);
source->references++;
ns_client_log(source, NS_LOGCATEGORY_CLIENT,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(10),
"ns_client_attach: ref = %d", 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;
ns_client_log(client, NS_LOGCATEGORY_CLIENT,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(10),
"ns_client_detach: ref = %d", client->references);
(void)exit_check(client);
}
isc_boolean_t
ns_client_shuttingdown(ns_client_t *client) {
return (ISC_TF(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);
client->mortal = ISC_TRUE;
return (ISC_R_SUCCESS);
}
static void
clientmgr_destroy(ns_clientmgr_t *manager) {
#if NMCTXS > 0
int i;
#endif
REQUIRE(ISC_LIST_EMPTY(manager->active));
REQUIRE(ISC_LIST_EMPTY(manager->inactive));
REQUIRE(ISC_LIST_EMPTY(manager->recursing));
MTRACE("clientmgr_destroy");
#if NMCTXS > 0
for (i = 0; i < NMCTXS; i++) {
if (manager->mctxpool[i] != NULL)
isc_mem_detach(&manager->mctxpool[i]);
}
#endif
DESTROYLOCK(&manager->lock);
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;
#if NMCTXS > 0
int i;
#endif
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);
ISC_LIST_INIT(manager->recursing);
#if NMCTXS > 0
manager->nextmctx = 0;
for (i = 0; i < NMCTXS; i++)
manager->mctxpool[i] = NULL;
#endif
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->recursing);
client != NULL;
client = ISC_LIST_NEXT(client, link))
isc_task_shutdown(client->task);
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) &&
ISC_LIST_EMPTY(manager->recursing))
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");
LOCK(&manager->lock);
for (i = 0; i < n; i++) {
isc_event_t *ev;
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;
}
ns_interface_attach(ifp, &client->interface);
client->state = NS_CLIENTSTATE_READY;
INSIST(client->recursionquota == NULL);
if (tcp) {
client->attributes |= NS_CLIENTATTR_TCP;
isc_socket_attach(ifp->tcpsocket,
&client->tcplistener);
} else {
isc_socket_t *sock;
dns_dispatch_attach(ifp->udpdispatch,
&client->dispatch);
sock = dns_dispatch_getsocket(client->dispatch);
isc_socket_attach(sock, &client->udpsocket);
}
client->manager = manager;
ISC_LIST_APPEND(manager->active, client, link);
client->list = &manager->active;
INSIST(client->nctls == 0);
client->nctls++;
ev = &client->ctlevent;
isc_task_send(client->task, &ev);
}
if (i != 0) {
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_checkaclsilent(ns_client_t *client, 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 != ISC_R_SUCCESS)
goto deny;
if (match > 0)
goto allow;
goto deny;
allow:
return (ISC_R_SUCCESS);
deny:
return (DNS_R_REFUSED);
}
isc_result_t
ns_client_checkacl(ns_client_t *client,
const char *opname, dns_acl_t *acl,
isc_boolean_t default_allow, int log_level)
{
isc_result_t result =
ns_client_checkaclsilent(client, acl, default_allow);
if (result == ISC_R_SUCCESS)
ns_client_log(client, DNS_LOGCATEGORY_SECURITY,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(3),
"%s approved", opname);
else
ns_client_log(client, DNS_LOGCATEGORY_SECURITY,
NS_LOGMODULE_CLIENT,
log_level, "%s denied", opname);
return (result);
}
static void
ns_client_name(ns_client_t *client, char *peerbuf, size_t len) {
if (client->peeraddr_valid)
isc_sockaddr_format(&client->peeraddr, peerbuf, len);
else
snprintf(peerbuf, len, "@%p", client);
}
void
ns_client_logv(ns_client_t *client, isc_logcategory_t *category,
isc_logmodule_t *module, int level, const char *fmt, va_list ap)
{
char msgbuf[2048];
char peerbuf[ISC_SOCKADDR_FORMATSIZE];
const char *name = "";
const char *sep = "";
vsnprintf(msgbuf, sizeof(msgbuf), fmt, ap);
ns_client_name(client, peerbuf, sizeof(peerbuf));
if (client->view != NULL && strcmp(client->view->name, "_bind") != 0 &&
strcmp(client->view->name, "_default") != 0) {
name = client->view->name;
sep = ": view ";
}
isc_log_write(ns_g_lctx, category, module, level,
"client %s%s%s: %s", peerbuf, sep, name, msgbuf);
}
void
ns_client_log(ns_client_t *client, isc_logcategory_t *category,
isc_logmodule_t *module, int level, const char *fmt, ...)
{
va_list ap;
if (! isc_log_wouldlog(ns_g_lctx, level))
return;
va_start(ap, fmt);
ns_client_logv(client, category, module, level, fmt, ap);
va_end(ap);
}
void
ns_client_aclmsg(const char *msg, dns_name_t *name, dns_rdatatype_t type,
dns_rdataclass_t rdclass, char *buf, size_t len)
{
char namebuf[DNS_NAME_FORMATSIZE];
char typebuf[DNS_RDATATYPE_FORMATSIZE];
char classbuf[DNS_RDATACLASS_FORMATSIZE];
dns_name_format(name, namebuf, sizeof(namebuf));
dns_rdatatype_format(type, typebuf, sizeof(typebuf));
dns_rdataclass_format(rdclass, classbuf, sizeof(classbuf));
(void)snprintf(buf, len, "%s '%s/%s/%s'", msg, namebuf, typebuf,
classbuf);
}
static void
ns_client_dumpmessage(ns_client_t *client, const char *reason) {
isc_buffer_t buffer;
char *buf = NULL;
int len = 1024;
isc_result_t result;
do {
buf = isc_mem_get(client->mctx, len);
if (buf == NULL)
break;
isc_buffer_init(&buffer, buf, len);
result = dns_message_totext(client->message,
&dns_master_style_debug,
0, &buffer);
if (result == ISC_R_NOSPACE) {
isc_mem_put(client->mctx, buf, len);
len += 1024;
} else if (result == ISC_R_SUCCESS)
ns_client_log(client, NS_LOGCATEGORY_UNMATCHED,
NS_LOGMODULE_CLIENT, ISC_LOG_DEBUG(1),
"%s\n%.*s", reason,
(int)isc_buffer_usedlength(&buffer),
buf);
} while (result == ISC_R_NOSPACE);
if (buf != NULL)
isc_mem_put(client->mctx, buf, len);
}
void
ns_client_dumprecursing(FILE *f, ns_clientmgr_t *manager) {
ns_client_t *client;
char namebuf[DNS_NAME_FORMATSIZE];
char peerbuf[ISC_SOCKADDR_FORMATSIZE];
const char *name;
const char *sep;
REQUIRE(VALID_MANAGER(manager));
LOCK(&manager->lock);
client = ISC_LIST_HEAD(manager->recursing);
while (client != NULL) {
ns_client_name(client, peerbuf, sizeof(peerbuf));
if (client->view != NULL &&
strcmp(client->view->name, "_bind") != 0 &&
strcmp(client->view->name, "_default") != 0) {
name = client->view->name;
sep = ": view ";
} else {
name = "";
sep = "";
}
dns_name_format(client->query.qname, namebuf, sizeof(namebuf));
fprintf(f, "; client %s%s%s: '%s' requesttime %d\n",
peerbuf, sep, name, namebuf, client->requesttime);
client = ISC_LIST_NEXT(client, link);
}
UNLOCK(&manager->lock);
}
void
ns_client_qnamereplace(ns_client_t *client, dns_name_t *name) {
if (client->manager != NULL)
LOCK(&client->manager->lock);
if (client->query.restarts > 0) {
dns_message_puttempname(client->message,
&client->query.qname);
}
client->query.qname = name;
if (client->manager != NULL)
UNLOCK(&client->manager->lock);
}