diff options
Diffstat (limited to 'lib/isc/netmgr/tcpdns.c')
| -rw-r--r-- | lib/isc/netmgr/tcpdns.c | 1500 |
1 files changed, 1500 insertions, 0 deletions
diff --git a/lib/isc/netmgr/tcpdns.c b/lib/isc/netmgr/tcpdns.c new file mode 100644 index 0000000..eda6aa6 --- /dev/null +++ b/lib/isc/netmgr/tcpdns.c @@ -0,0 +1,1500 @@ +/* + * Copyright (C) Internet Systems Consortium, Inc. ("ISC") + * + * SPDX-License-Identifier: MPL-2.0 + * + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, you can obtain one at https://mozilla.org/MPL/2.0/. + * + * See the COPYRIGHT file distributed with this work for additional + * information regarding copyright ownership. + */ + +#include <libgen.h> +#include <unistd.h> +#include <uv.h> + +#include <isc/atomic.h> +#include <isc/barrier.h> +#include <isc/buffer.h> +#include <isc/condition.h> +#include <isc/errno.h> +#include <isc/log.h> +#include <isc/magic.h> +#include <isc/mem.h> +#include <isc/netmgr.h> +#include <isc/quota.h> +#include <isc/random.h> +#include <isc/refcount.h> +#include <isc/region.h> +#include <isc/result.h> +#include <isc/sockaddr.h> +#include <isc/stdtime.h> +#include <isc/thread.h> +#include <isc/util.h> + +#include "netmgr-int.h" +#include "uv-compat.h" + +static atomic_uint_fast32_t last_tcpdnsquota_log = 0; + +static bool +can_log_tcpdns_quota(void) { + isc_stdtime_t now, last; + + isc_stdtime_get(&now); + last = atomic_exchange_relaxed(&last_tcpdnsquota_log, now); + if (now != last) { + return (true); + } + + return (false); +} + +static isc_result_t +tcpdns_connect_direct(isc_nmsocket_t *sock, isc__nm_uvreq_t *req); + +static void +tcpdns_close_direct(isc_nmsocket_t *sock); + +static void +tcpdns_connect_cb(uv_connect_t *uvreq, int status); + +static void +tcpdns_connection_cb(uv_stream_t *server, int status); + +static void +tcpdns_close_cb(uv_handle_t *uvhandle); + +static isc_result_t +accept_connection(isc_nmsocket_t *ssock, isc_quota_t *quota); + +static void +quota_accept_cb(isc_quota_t *quota, void *sock0); + +static void +stop_tcpdns_parent(isc_nmsocket_t *sock); +static void +stop_tcpdns_child(isc_nmsocket_t *sock); + +static isc_result_t +tcpdns_connect_direct(isc_nmsocket_t *sock, isc__nm_uvreq_t *req) { + isc__networker_t *worker = NULL; + isc_result_t result = ISC_R_UNSET; + int r; + + REQUIRE(VALID_NMSOCK(sock)); + REQUIRE(VALID_UVREQ(req)); + + REQUIRE(isc__nm_in_netthread()); + REQUIRE(sock->tid == isc_nm_tid()); + + worker = &sock->mgr->workers[sock->tid]; + + atomic_store(&sock->connecting, true); + + r = uv_tcp_init(&worker->loop, &sock->uv_handle.tcp); + UV_RUNTIME_CHECK(uv_tcp_init, r); + uv_handle_set_data(&sock->uv_handle.handle, sock); + + r = uv_timer_init(&worker->loop, &sock->read_timer); + UV_RUNTIME_CHECK(uv_timer_init, r); + uv_handle_set_data((uv_handle_t *)&sock->read_timer, sock); + + if (isc__nm_closing(sock)) { + result = ISC_R_SHUTTINGDOWN; + goto error; + } + + r = uv_tcp_open(&sock->uv_handle.tcp, sock->fd); + if (r != 0) { + isc__nm_closesocket(sock->fd); + isc__nm_incstats(sock, STATID_OPENFAIL); + goto done; + } + isc__nm_incstats(sock, STATID_OPEN); + + if (req->local.length != 0) { + r = uv_tcp_bind(&sock->uv_handle.tcp, &req->local.type.sa, 0); + /* + * In case of shared socket UV_EINVAL will be returned and needs + * to be ignored + */ + if (r != 0 && r != UV_EINVAL) { + isc__nm_incstats(sock, STATID_BINDFAIL); + goto done; + } + } + + isc__nm_set_network_buffers(sock->mgr, &sock->uv_handle.handle); + + uv_handle_set_data(&req->uv_req.handle, req); + r = uv_tcp_connect(&req->uv_req.connect, &sock->uv_handle.tcp, + &req->peer.type.sa, tcpdns_connect_cb); + if (r != 0) { + isc__nm_incstats(sock, STATID_CONNECTFAIL); + goto done; + } + + uv_handle_set_data((uv_handle_t *)&sock->read_timer, + &req->uv_req.connect); + isc__nmsocket_timer_start(sock); + + atomic_store(&sock->connected, true); + +done: + result = isc__nm_uverr2result(r); +error: + LOCK(&sock->lock); + sock->result = result; + SIGNAL(&sock->cond); + if (!atomic_load(&sock->active)) { + WAIT(&sock->scond, &sock->lock); + } + INSIST(atomic_load(&sock->active)); + UNLOCK(&sock->lock); + + return (result); +} + +void +isc__nm_async_tcpdnsconnect(isc__networker_t *worker, isc__netievent_t *ev0) { + isc__netievent_tcpdnsconnect_t *ievent = + (isc__netievent_tcpdnsconnect_t *)ev0; + isc_nmsocket_t *sock = ievent->sock; + isc__nm_uvreq_t *req = ievent->req; + isc_result_t result = ISC_R_SUCCESS; + + UNUSED(worker); + + REQUIRE(VALID_NMSOCK(sock)); + REQUIRE(sock->type == isc_nm_tcpdnssocket); + REQUIRE(sock->parent == NULL); + REQUIRE(sock->tid == isc_nm_tid()); + + result = tcpdns_connect_direct(sock, req); + if (result != ISC_R_SUCCESS) { + isc__nmsocket_clearcb(sock); + isc__nm_connectcb(sock, req, result, true); + atomic_store(&sock->active, false); + isc__nm_tcpdns_close(sock); + } + + /* + * The sock is now attached to the handle. + */ + isc__nmsocket_detach(&sock); +} + +static void +tcpdns_connect_cb(uv_connect_t *uvreq, int status) { + isc_result_t result = ISC_R_UNSET; + isc__nm_uvreq_t *req = NULL; + isc_nmsocket_t *sock = uv_handle_get_data((uv_handle_t *)uvreq->handle); + struct sockaddr_storage ss; + int r; + + REQUIRE(VALID_NMSOCK(sock)); + REQUIRE(sock->tid == isc_nm_tid()); + + req = uv_handle_get_data((uv_handle_t *)uvreq); + + REQUIRE(VALID_UVREQ(req)); + REQUIRE(VALID_NMHANDLE(req->handle)); + + if (atomic_load(&sock->timedout)) { + result = ISC_R_TIMEDOUT; + goto error; + } else if (isc__nm_closing(sock)) { + /* Network manager shutting down */ + result = ISC_R_SHUTTINGDOWN; + goto error; + } else if (isc__nmsocket_closing(sock)) { + /* Connection canceled */ + result = ISC_R_CANCELED; + goto error; + } else if (status == UV_ETIMEDOUT) { + /* Timeout status code here indicates hard error */ + result = ISC_R_TIMEDOUT; + goto error; + } else if (status == UV_EADDRINUSE) { + /* + * On FreeBSD the TCP connect() call sometimes results in a + * spurious transient EADDRINUSE. Try a few more times before + * giving up. + */ + if (--req->connect_tries > 0) { + r = uv_tcp_connect( + &req->uv_req.connect, &sock->uv_handle.tcp, + &req->peer.type.sa, tcpdns_connect_cb); + if (r != 0) { + result = isc__nm_uverr2result(r); + goto error; + } + return; + } + result = isc__nm_uverr2result(status); + goto error; + } else if (status != 0) { + result = isc__nm_uverr2result(status); + goto error; + } + + isc__nmsocket_timer_stop(sock); + uv_handle_set_data((uv_handle_t *)&sock->read_timer, sock); + + isc__nm_incstats(sock, STATID_CONNECT); + r = uv_tcp_getpeername(&sock->uv_handle.tcp, (struct sockaddr *)&ss, + &(int){ sizeof(ss) }); + if (r != 0) { + result = isc__nm_uverr2result(r); + goto error; + } + + atomic_store(&sock->connecting, false); + + result = isc_sockaddr_fromsockaddr(&sock->peer, (struct sockaddr *)&ss); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + + isc__nm_connectcb(sock, req, ISC_R_SUCCESS, false); + + return; +error: + isc__nm_failed_connect_cb(sock, req, result, false); +} + +void +isc_nm_tcpdnsconnect(isc_nm_t *mgr, isc_sockaddr_t *local, isc_sockaddr_t *peer, + isc_nm_cb_t cb, void *cbarg, unsigned int timeout, + size_t extrahandlesize) { + isc_result_t result = ISC_R_SUCCESS; + isc_nmsocket_t *sock = NULL; + isc__netievent_tcpdnsconnect_t *ievent = NULL; + isc__nm_uvreq_t *req = NULL; + sa_family_t sa_family; + + REQUIRE(VALID_NM(mgr)); + REQUIRE(local != NULL); + REQUIRE(peer != NULL); + + sa_family = peer->type.sa.sa_family; + + sock = isc_mem_get(mgr->mctx, sizeof(*sock)); + isc__nmsocket_init(sock, mgr, isc_nm_tcpdnssocket, local); + + sock->extrahandlesize = extrahandlesize; + sock->connect_timeout = timeout; + sock->result = ISC_R_UNSET; + atomic_init(&sock->client, true); + + req = isc__nm_uvreq_get(mgr, sock); + req->cb.connect = cb; + req->cbarg = cbarg; + req->peer = *peer; + req->local = *local; + req->handle = isc__nmhandle_get(sock, &req->peer, &sock->iface); + + result = isc__nm_socket(sa_family, SOCK_STREAM, 0, &sock->fd); + if (result != ISC_R_SUCCESS) { + if (isc__nm_in_netthread()) { + sock->tid = isc_nm_tid(); + } + isc__nmsocket_clearcb(sock); + isc__nm_connectcb(sock, req, result, true); + atomic_store(&sock->closed, true); + isc__nmsocket_detach(&sock); + return; + } + + (void)isc__nm_socket_min_mtu(sock->fd, sa_family); + (void)isc__nm_socket_tcp_maxseg(sock->fd, NM_MAXSEG); + + /* 2 minute timeout */ + result = isc__nm_socket_connectiontimeout(sock->fd, 120 * 1000); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + + ievent = isc__nm_get_netievent_tcpdnsconnect(mgr, sock, req); + + if (isc__nm_in_netthread()) { + atomic_store(&sock->active, true); + sock->tid = isc_nm_tid(); + isc__nm_async_tcpdnsconnect(&mgr->workers[sock->tid], + (isc__netievent_t *)ievent); + isc__nm_put_netievent_tcpdnsconnect(mgr, ievent); + } else { + atomic_init(&sock->active, false); + sock->tid = isc_random_uniform(mgr->nworkers); + isc__nm_enqueue_ievent(&mgr->workers[sock->tid], + (isc__netievent_t *)ievent); + } + + LOCK(&sock->lock); + while (sock->result == ISC_R_UNSET) { + WAIT(&sock->cond, &sock->lock); + } + atomic_store(&sock->active, true); + BROADCAST(&sock->scond); + UNLOCK(&sock->lock); +} + +static uv_os_sock_t +isc__nm_tcpdns_lb_socket(isc_nm_t *mgr, sa_family_t sa_family) { + isc_result_t result; + uv_os_sock_t sock; + + result = isc__nm_socket(sa_family, SOCK_STREAM, 0, &sock); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + + (void)isc__nm_socket_incoming_cpu(sock); + (void)isc__nm_socket_v6only(sock, sa_family); + + /* FIXME: set mss */ + + result = isc__nm_socket_reuse(sock); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + + if (mgr->load_balance_sockets) { + result = isc__nm_socket_reuse_lb(sock); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + } + + return (sock); +} + +static void +enqueue_stoplistening(isc_nmsocket_t *sock) { + isc__netievent_tcpdnsstop_t *ievent = + isc__nm_get_netievent_tcpdnsstop(sock->mgr, sock); + isc__nm_enqueue_ievent(&sock->mgr->workers[sock->tid], + (isc__netievent_t *)ievent); +} + +static void +start_tcpdns_child(isc_nm_t *mgr, isc_sockaddr_t *iface, isc_nmsocket_t *sock, + uv_os_sock_t fd, int tid) { + isc__netievent_tcpdnslisten_t *ievent = NULL; + isc_nmsocket_t *csock = &sock->children[tid]; + + isc__nmsocket_init(csock, mgr, isc_nm_tcpdnssocket, iface); + csock->parent = sock; + csock->accept_cb = sock->accept_cb; + csock->accept_cbarg = sock->accept_cbarg; + csock->recv_cb = sock->recv_cb; + csock->recv_cbarg = sock->recv_cbarg; + csock->extrahandlesize = sock->extrahandlesize; + csock->backlog = sock->backlog; + csock->tid = tid; + /* + * We don't attach to quota, just assign - to avoid + * increasing quota unnecessarily. + */ + csock->pquota = sock->pquota; + isc_quota_cb_init(&csock->quotacb, quota_accept_cb, csock); + + if (mgr->load_balance_sockets) { + UNUSED(fd); + csock->fd = isc__nm_tcpdns_lb_socket(mgr, + iface->type.sa.sa_family); + } else { + csock->fd = dup(fd); + } + REQUIRE(csock->fd >= 0); + + ievent = isc__nm_get_netievent_tcpdnslisten(mgr, csock); + isc__nm_maybe_enqueue_ievent(&mgr->workers[tid], + (isc__netievent_t *)ievent); +} +isc_result_t +isc_nm_listentcpdns(isc_nm_t *mgr, isc_sockaddr_t *iface, + isc_nm_recv_cb_t recv_cb, void *recv_cbarg, + isc_nm_accept_cb_t accept_cb, void *accept_cbarg, + size_t extrahandlesize, int backlog, isc_quota_t *quota, + isc_nmsocket_t **sockp) { + isc_result_t result = ISC_R_SUCCESS; + isc_nmsocket_t *sock = NULL; + size_t children_size = 0; + uv_os_sock_t fd = -1; + + REQUIRE(VALID_NM(mgr)); + + sock = isc_mem_get(mgr->mctx, sizeof(*sock)); + isc__nmsocket_init(sock, mgr, isc_nm_tcpdnslistener, iface); + + atomic_init(&sock->rchildren, 0); + sock->nchildren = mgr->nworkers; + children_size = sock->nchildren * sizeof(sock->children[0]); + sock->children = isc_mem_get(mgr->mctx, children_size); + memset(sock->children, 0, children_size); + + sock->result = ISC_R_UNSET; + sock->accept_cb = accept_cb; + sock->accept_cbarg = accept_cbarg; + sock->recv_cb = recv_cb; + sock->recv_cbarg = recv_cbarg; + sock->extrahandlesize = extrahandlesize; + sock->backlog = backlog; + sock->pquota = quota; + + sock->tid = 0; + sock->fd = -1; + + if (!mgr->load_balance_sockets) { + fd = isc__nm_tcpdns_lb_socket(mgr, iface->type.sa.sa_family); + } + + isc_barrier_init(&sock->startlistening, sock->nchildren); + + for (size_t i = 0; i < sock->nchildren; i++) { + if ((int)i == isc_nm_tid()) { + continue; + } + start_tcpdns_child(mgr, iface, sock, fd, i); + } + + if (isc__nm_in_netthread()) { + start_tcpdns_child(mgr, iface, sock, fd, isc_nm_tid()); + } + + if (!mgr->load_balance_sockets) { + isc__nm_closesocket(fd); + } + + LOCK(&sock->lock); + while (atomic_load(&sock->rchildren) != sock->nchildren) { + WAIT(&sock->cond, &sock->lock); + } + result = sock->result; + atomic_store(&sock->active, true); + UNLOCK(&sock->lock); + + INSIST(result != ISC_R_UNSET); + + if (result == ISC_R_SUCCESS) { + REQUIRE(atomic_load(&sock->rchildren) == sock->nchildren); + *sockp = sock; + } else { + atomic_store(&sock->active, false); + enqueue_stoplistening(sock); + isc_nmsocket_close(&sock); + } + + return (result); +} + +void +isc__nm_async_tcpdnslisten(isc__networker_t *worker, isc__netievent_t *ev0) { + isc__netievent_tcpdnslisten_t *ievent = + (isc__netievent_tcpdnslisten_t *)ev0; + sa_family_t sa_family; + int r; + int flags = 0; + isc_nmsocket_t *sock = NULL; + isc_result_t result = ISC_R_UNSET; + isc_nm_t *mgr = NULL; + + REQUIRE(VALID_NMSOCK(ievent->sock)); + REQUIRE(ievent->sock->tid == isc_nm_tid()); + REQUIRE(VALID_NMSOCK(ievent->sock->parent)); + + sock = ievent->sock; + sa_family = sock->iface.type.sa.sa_family; + mgr = sock->mgr; + + REQUIRE(sock->type == isc_nm_tcpdnssocket); + REQUIRE(sock->parent != NULL); + REQUIRE(sock->tid == isc_nm_tid()); + + (void)isc__nm_socket_min_mtu(sock->fd, sa_family); + (void)isc__nm_socket_tcp_maxseg(sock->fd, NM_MAXSEG); + + r = uv_tcp_init(&worker->loop, &sock->uv_handle.tcp); + UV_RUNTIME_CHECK(uv_tcp_init, r); + uv_handle_set_data(&sock->uv_handle.handle, sock); + /* This keeps the socket alive after everything else is gone */ + isc__nmsocket_attach(sock, &(isc_nmsocket_t *){ NULL }); + + r = uv_timer_init(&worker->loop, &sock->read_timer); + UV_RUNTIME_CHECK(uv_timer_init, r); + uv_handle_set_data((uv_handle_t *)&sock->read_timer, sock); + + LOCK(&sock->parent->lock); + + r = uv_tcp_open(&sock->uv_handle.tcp, sock->fd); + if (r < 0) { + isc__nm_closesocket(sock->fd); + isc__nm_incstats(sock, STATID_OPENFAIL); + goto done; + } + isc__nm_incstats(sock, STATID_OPEN); + + if (sa_family == AF_INET6) { + flags = UV_TCP_IPV6ONLY; + } + + if (mgr->load_balance_sockets) { + r = isc_uv_tcp_freebind(&sock->uv_handle.tcp, + &sock->iface.type.sa, flags); + if (r < 0) { + isc__nm_incstats(sock, STATID_BINDFAIL); + goto done; + } + } else { + if (sock->parent->fd == -1) { + r = isc_uv_tcp_freebind(&sock->uv_handle.tcp, + &sock->iface.type.sa, flags); + if (r < 0) { + isc__nm_incstats(sock, STATID_BINDFAIL); + goto done; + } + sock->parent->uv_handle.tcp.flags = + sock->uv_handle.tcp.flags; + sock->parent->fd = sock->fd; + } else { + /* The socket is already bound, just copy the flags */ + sock->uv_handle.tcp.flags = + sock->parent->uv_handle.tcp.flags; + } + } + + isc__nm_set_network_buffers(sock->mgr, &sock->uv_handle.handle); + + /* + * The callback will run in the same thread uv_listen() was called + * from, so a race with tcpdns_connection_cb() isn't possible. + */ + r = uv_listen((uv_stream_t *)&sock->uv_handle.tcp, sock->backlog, + tcpdns_connection_cb); + if (r != 0) { + isc_log_write(isc_lctx, ISC_LOGCATEGORY_GENERAL, + ISC_LOGMODULE_NETMGR, ISC_LOG_ERROR, + "uv_listen failed: %s", + isc_result_totext(isc__nm_uverr2result(r))); + isc__nm_incstats(sock, STATID_BINDFAIL); + goto done; + } + + atomic_store(&sock->listening, true); + +done: + result = isc__nm_uverr2result(r); + if (result != ISC_R_SUCCESS) { + sock->pquota = NULL; + } + + atomic_fetch_add(&sock->parent->rchildren, 1); + if (sock->parent->result == ISC_R_UNSET) { + sock->parent->result = result; + } + SIGNAL(&sock->parent->cond); + UNLOCK(&sock->parent->lock); + + isc_barrier_wait(&sock->parent->startlistening); +} + +static void +tcpdns_connection_cb(uv_stream_t *server, int status) { + isc_nmsocket_t *ssock = uv_handle_get_data((uv_handle_t *)server); + isc_result_t result; + isc_quota_t *quota = NULL; + + if (status != 0) { + result = isc__nm_uverr2result(status); + goto done; + } + + REQUIRE(VALID_NMSOCK(ssock)); + REQUIRE(ssock->tid == isc_nm_tid()); + + if (isc__nmsocket_closing(ssock)) { + result = ISC_R_CANCELED; + goto done; + } + + if (ssock->pquota != NULL) { + result = isc_quota_attach_cb(ssock->pquota, "a, + &ssock->quotacb); + if (result == ISC_R_QUOTA) { + isc__nm_incstats(ssock, STATID_ACCEPTFAIL); + goto done; + } + } + + result = accept_connection(ssock, quota); +done: + isc__nm_accept_connection_log(result, can_log_tcpdns_quota()); +} + +void +isc__nm_tcpdns_stoplistening(isc_nmsocket_t *sock) { + REQUIRE(VALID_NMSOCK(sock)); + REQUIRE(sock->type == isc_nm_tcpdnslistener); + + if (!atomic_compare_exchange_strong(&sock->closing, &(bool){ false }, + true)) + { + UNREACHABLE(); + } + + if (!isc__nm_in_netthread()) { + enqueue_stoplistening(sock); + } else { + stop_tcpdns_parent(sock); + } +} + +void +isc__nm_async_tcpdnsstop(isc__networker_t *worker, isc__netievent_t *ev0) { + isc__netievent_tcpdnsstop_t *ievent = + (isc__netievent_tcpdnsstop_t *)ev0; + isc_nmsocket_t *sock = ievent->sock; + + UNUSED(worker); + + REQUIRE(VALID_NMSOCK(sock)); + REQUIRE(sock->tid == isc_nm_tid()); + + if (sock->parent != NULL) { + stop_tcpdns_child(sock); + return; + } + + stop_tcpdns_parent(sock); +} + +void +isc__nm_tcpdns_failed_read_cb(isc_nmsocket_t *sock, isc_result_t result) { + REQUIRE(VALID_NMSOCK(sock)); + REQUIRE(result != ISC_R_SUCCESS); + + isc__nmsocket_timer_stop(sock); + isc__nm_stop_reading(sock); + + if (!sock->recv_read) { + goto destroy; + } + sock->recv_read = false; + + if (sock->recv_cb != NULL) { + isc__nm_uvreq_t *req = isc__nm_get_read_req(sock, NULL); + isc__nmsocket_clearcb(sock); + isc__nm_readcb(sock, req, result); + } + +destroy: + isc__nmsocket_prep_destroy(sock); + + /* + * We need to detach from quota after the read callback function had a + * chance to be executed. + */ + if (sock->quota != NULL) { + isc_quota_detach(&sock->quota); + } +} + +void +isc__nm_tcpdns_read(isc_nmhandle_t *handle, isc_nm_recv_cb_t cb, void *cbarg) { + REQUIRE(VALID_NMHANDLE(handle)); + REQUIRE(VALID_NMSOCK(handle->sock)); + + isc_nmsocket_t *sock = handle->sock; + isc__netievent_tcpdnsread_t *ievent = NULL; + + REQUIRE(sock->type == isc_nm_tcpdnssocket); + REQUIRE(sock->statichandle == handle); + + sock->recv_cb = cb; + sock->recv_cbarg = cbarg; + sock->recv_read = true; + if (sock->read_timeout == 0) { + sock->read_timeout = + (atomic_load(&sock->keepalive) + ? atomic_load(&sock->mgr->keepalive) + : atomic_load(&sock->mgr->idle)); + } + + ievent = isc__nm_get_netievent_tcpdnsread(sock->mgr, sock); + + /* + * This MUST be done asynchronously, no matter which thread we're + * in. The callback function for isc_nm_read() often calls + * isc_nm_read() again; if we tried to do that synchronously + * we'd clash in processbuffer() and grow the stack indefinitely. + */ + isc__nm_enqueue_ievent(&sock->mgr->workers[sock->tid], + (isc__netievent_t *)ievent); + + return; +} + +void +isc__nm_async_tcpdnsread(isc__networker_t *worker, isc__netievent_t *ev0) { + isc__netievent_tcpdnsread_t *ievent = + (isc__netievent_tcpdnsread_t *)ev0; + isc_nmsocket_t *sock = ievent->sock; + isc_result_t result; + + UNUSED(worker); + + REQUIRE(VALID_NMSOCK(sock)); + REQUIRE(sock->tid == isc_nm_tid()); + + if (isc__nmsocket_closing(sock)) { + result = ISC_R_CANCELED; + } else { + result = isc__nm_process_sock_buffer(sock); + } + + if (result != ISC_R_SUCCESS) { + atomic_store(&sock->reading, true); + isc__nm_failed_read_cb(sock, result, false); + } +} + +/* + * Process a single packet from the incoming buffer. + * + * Return ISC_R_SUCCESS and attach 'handlep' to a handle if something + * was processed; return ISC_R_NOMORE if there isn't a full message + * to be processed. + * + * The caller will need to unreference the handle. + */ +isc_result_t +isc__nm_tcpdns_processbuffer(isc_nmsocket_t *sock) { + size_t len; + isc__nm_uvreq_t *req = NULL; + isc_nmhandle_t *handle = NULL; + + REQUIRE(VALID_NMSOCK(sock)); + REQUIRE(sock->tid == isc_nm_tid()); + + if (isc__nmsocket_closing(sock)) { + return (ISC_R_CANCELED); + } + + /* + * If we don't even have the length yet, we can't do + * anything. + */ + if (sock->buf_len < 2) { + return (ISC_R_NOMORE); + } + + /* + * Process the first packet from the buffer, leaving + * the rest (if any) for later. + */ + len = ntohs(*(uint16_t *)sock->buf); + if (len > sock->buf_len - 2) { + return (ISC_R_NOMORE); + } + + if (sock->recv_cb == NULL) { + /* + * recv_cb has been cleared - there is + * nothing to do + */ + return (ISC_R_CANCELED); + } else if (sock->statichandle == NULL && + atomic_load(&sock->connected) && + !atomic_load(&sock->connecting)) + { + /* + * It seems that some unexpected data (a DNS message) has + * arrived while we are wrapping up. + */ + return (ISC_R_CANCELED); + } + + req = isc__nm_get_read_req(sock, NULL); + REQUIRE(VALID_UVREQ(req)); + + /* + * We need to launch isc__nm_resume_processing() after the buffer + * has been consumed, thus we must delay detaching the handle. + */ + isc_nmhandle_attach(req->handle, &handle); + + /* + * The callback will be called synchronously because the + * result is ISC_R_SUCCESS, so we don't need to have + * the buffer on the heap + */ + req->uvbuf.base = (char *)sock->buf + 2; + req->uvbuf.len = len; + + /* + * If isc__nm_tcpdns_read() was called, it will be satisfied by single + * DNS message in the next call. + */ + sock->recv_read = false; + + /* + * An assertion failure here means that there's an erroneous + * extra nmhandle detach happening in the callback and + * isc__nm_resume_processing() is called while we're + * processing the buffer. + */ + REQUIRE(sock->processing == false); + sock->processing = true; + isc__nm_readcb(sock, req, ISC_R_SUCCESS); + sock->processing = false; + + len += 2; + sock->buf_len -= len; + if (sock->buf_len > 0) { + memmove(sock->buf, sock->buf + len, sock->buf_len); + } + + isc_nmhandle_detach(&handle); + + return (ISC_R_SUCCESS); +} + +void +isc__nm_tcpdns_read_cb(uv_stream_t *stream, ssize_t nread, + const uv_buf_t *buf) { + isc_nmsocket_t *sock = uv_handle_get_data((uv_handle_t *)stream); + uint8_t *base = NULL; + size_t len; + isc_result_t result; + + REQUIRE(VALID_NMSOCK(sock)); + REQUIRE(sock->tid == isc_nm_tid()); + REQUIRE(atomic_load(&sock->reading)); + REQUIRE(buf != NULL); + + if (isc__nmsocket_closing(sock)) { + isc__nm_failed_read_cb(sock, ISC_R_CANCELED, true); + goto free; + } + + if (nread < 0) { + if (nread != UV_EOF) { + isc__nm_incstats(sock, STATID_RECVFAIL); + } + + isc__nm_failed_read_cb(sock, isc__nm_uverr2result(nread), true); + goto free; + } + + base = (uint8_t *)buf->base; + len = nread; + + /* + * FIXME: We can avoid the memmove here if we know we have received full + * packet; e.g. we should be smarter, a.s. there are just few situations + * + * The tcp_alloc_buf should be smarter and point the uv_read_start to + * the position where previous read has ended in the sock->buf, that way + * the data could be read directly into sock->buf. + */ + + if (sock->buf_len + len > sock->buf_size) { + isc__nm_alloc_dnsbuf(sock, sock->buf_len + len); + } + memmove(sock->buf + sock->buf_len, base, len); + sock->buf_len += len; + + if (!atomic_load(&sock->client)) { + sock->read_timeout = atomic_load(&sock->mgr->idle); + } + + result = isc__nm_process_sock_buffer(sock); + if (result != ISC_R_SUCCESS) { + isc__nm_failed_read_cb(sock, result, true); + } +free: + if (nread < 0) { + /* + * The buffer may be a null buffer on error. + */ + if (buf->base == NULL && buf->len == 0) { + return; + } + } + + isc__nm_free_uvbuf(sock, buf); +} + +static void +quota_accept_cb(isc_quota_t *quota, void *sock0) { + isc_nmsocket_t *sock = (isc_nmsocket_t *)sock0; + + REQUIRE(VALID_NMSOCK(sock)); + + /* + * Create a tcpdnsaccept event and pass it using the async channel. + */ + + isc__netievent_tcpdnsaccept_t *ievent = + isc__nm_get_netievent_tcpdnsaccept(sock->mgr, sock, quota); + isc__nm_maybe_enqueue_ievent(&sock->mgr->workers[sock->tid], + (isc__netievent_t *)ievent); +} + +/* + * This is called after we get a quota_accept_cb() callback. + */ +void +isc__nm_async_tcpdnsaccept(isc__networker_t *worker, isc__netievent_t *ev0) { + isc__netievent_tcpdnsaccept_t *ievent = + (isc__netievent_tcpdnsaccept_t *)ev0; + isc_result_t result; + + UNUSED(worker); + + REQUIRE(VALID_NMSOCK(ievent->sock)); + REQUIRE(ievent->sock->tid == isc_nm_tid()); + + result = accept_connection(ievent->sock, ievent->quota); + isc__nm_accept_connection_log(result, can_log_tcpdns_quota()); +} + +static isc_result_t +accept_connection(isc_nmsocket_t *ssock, isc_quota_t *quota) { + isc_nmsocket_t *csock = NULL; + isc__networker_t *worker = NULL; + int r; + isc_result_t result; + struct sockaddr_storage peer_ss; + struct sockaddr_storage local_ss; + isc_sockaddr_t local; + isc_nmhandle_t *handle = NULL; + + REQUIRE(VALID_NMSOCK(ssock)); + REQUIRE(ssock->tid == isc_nm_tid()); + + if (isc__nmsocket_closing(ssock)) { + if (quota != NULL) { + isc_quota_detach("a); + } + return (ISC_R_CANCELED); + } + + REQUIRE(ssock->accept_cb != NULL); + + csock = isc_mem_get(ssock->mgr->mctx, sizeof(isc_nmsocket_t)); + isc__nmsocket_init(csock, ssock->mgr, isc_nm_tcpdnssocket, + &ssock->iface); + csock->tid = ssock->tid; + csock->extrahandlesize = ssock->extrahandlesize; + isc__nmsocket_attach(ssock, &csock->server); + csock->recv_cb = ssock->recv_cb; + csock->recv_cbarg = ssock->recv_cbarg; + csock->quota = quota; + atomic_init(&csock->accepting, true); + + worker = &csock->mgr->workers[csock->tid]; + + r = uv_tcp_init(&worker->loop, &csock->uv_handle.tcp); + UV_RUNTIME_CHECK(uv_tcp_init, r); + uv_handle_set_data(&csock->uv_handle.handle, csock); + + r = uv_timer_init(&worker->loop, &csock->read_timer); + UV_RUNTIME_CHECK(uv_timer_init, r); + uv_handle_set_data((uv_handle_t *)&csock->read_timer, csock); + + r = uv_accept(&ssock->uv_handle.stream, &csock->uv_handle.stream); + if (r != 0) { + result = isc__nm_uverr2result(r); + goto failure; + } + + r = uv_tcp_getpeername(&csock->uv_handle.tcp, + (struct sockaddr *)&peer_ss, + &(int){ sizeof(peer_ss) }); + if (r != 0) { + result = isc__nm_uverr2result(r); + goto failure; + } + + result = isc_sockaddr_fromsockaddr(&csock->peer, + (struct sockaddr *)&peer_ss); + if (result != ISC_R_SUCCESS) { + goto failure; + } + + r = uv_tcp_getsockname(&csock->uv_handle.tcp, + (struct sockaddr *)&local_ss, + &(int){ sizeof(local_ss) }); + if (r != 0) { + result = isc__nm_uverr2result(r); + goto failure; + } + + result = isc_sockaddr_fromsockaddr(&local, + (struct sockaddr *)&local_ss); + if (result != ISC_R_SUCCESS) { + goto failure; + } + + /* + * The handle will be either detached on acceptcb failure or in the + * readcb. + */ + handle = isc__nmhandle_get(csock, NULL, &local); + + result = ssock->accept_cb(handle, ISC_R_SUCCESS, ssock->accept_cbarg); + if (result != ISC_R_SUCCESS) { + isc_nmhandle_detach(&handle); + goto failure; + } + + atomic_store(&csock->accepting, false); + + isc__nm_incstats(csock, STATID_ACCEPT); + + csock->read_timeout = atomic_load(&csock->mgr->init); + + csock->closehandle_cb = isc__nm_resume_processing; + + /* + * We need to keep the handle alive until we fail to read or connection + * is closed by the other side, it will be detached via + * prep_destroy()->tcpdns_close_direct(). + */ + isc_nmhandle_attach(handle, &csock->recv_handle); + result = isc__nm_process_sock_buffer(csock); + if (result != ISC_R_SUCCESS) { + isc_nmhandle_detach(&csock->recv_handle); + isc_nmhandle_detach(&handle); + goto failure; + } + + /* + * The initial timer has been set, update the read timeout for the next + * reads. + */ + csock->read_timeout = (atomic_load(&csock->keepalive) + ? atomic_load(&csock->mgr->keepalive) + : atomic_load(&csock->mgr->idle)); + + isc_nmhandle_detach(&handle); + + /* + * sock is now attached to the handle. + */ + isc__nmsocket_detach(&csock); + + return (ISC_R_SUCCESS); + +failure: + + atomic_store(&csock->active, false); + + isc__nm_failed_accept_cb(csock, result); + + isc__nmsocket_prep_destroy(csock); + + isc__nmsocket_detach(&csock); + + return (result); +} + +void +isc__nm_tcpdns_send(isc_nmhandle_t *handle, isc_region_t *region, + isc_nm_cb_t cb, void *cbarg) { + isc__netievent_tcpdnssend_t *ievent = NULL; + isc__nm_uvreq_t *uvreq = NULL; + isc_nmsocket_t *sock = NULL; + + REQUIRE(VALID_NMHANDLE(handle)); + + sock = handle->sock; + + REQUIRE(VALID_NMSOCK(sock)); + REQUIRE(sock->type == isc_nm_tcpdnssocket); + + uvreq = isc__nm_uvreq_get(sock->mgr, sock); + *(uint16_t *)uvreq->tcplen = htons(region->length); + uvreq->uvbuf.base = (char *)region->base; + uvreq->uvbuf.len = region->length; + + isc_nmhandle_attach(handle, &uvreq->handle); + + uvreq->cb.send = cb; + uvreq->cbarg = cbarg; + + ievent = isc__nm_get_netievent_tcpdnssend(sock->mgr, sock, uvreq); + isc__nm_maybe_enqueue_ievent(&sock->mgr->workers[sock->tid], + (isc__netievent_t *)ievent); + + return; +} + +static void +tcpdns_send_cb(uv_write_t *req, int status) { + isc__nm_uvreq_t *uvreq = (isc__nm_uvreq_t *)req->data; + isc_nmsocket_t *sock = NULL; + + REQUIRE(VALID_UVREQ(uvreq)); + REQUIRE(VALID_NMSOCK(uvreq->sock)); + + sock = uvreq->sock; + + isc_nm_timer_stop(uvreq->timer); + isc_nm_timer_detach(&uvreq->timer); + + if (status < 0) { + isc__nm_incstats(sock, STATID_SENDFAIL); + isc__nm_failed_send_cb(sock, uvreq, + isc__nm_uverr2result(status)); + return; + } + + isc__nm_sendcb(sock, uvreq, ISC_R_SUCCESS, false); +} + +/* + * Handle 'tcpsend' async event - send a packet on the socket + */ +void +isc__nm_async_tcpdnssend(isc__networker_t *worker, isc__netievent_t *ev0) { + isc_result_t result; + isc__netievent_tcpdnssend_t *ievent = + (isc__netievent_tcpdnssend_t *)ev0; + isc_nmsocket_t *sock = NULL; + isc__nm_uvreq_t *uvreq = NULL; + int r, nbufs = 2; + + UNUSED(worker); + + REQUIRE(VALID_UVREQ(ievent->req)); + REQUIRE(VALID_NMSOCK(ievent->sock)); + REQUIRE(ievent->sock->type == isc_nm_tcpdnssocket); + REQUIRE(ievent->sock->tid == isc_nm_tid()); + + sock = ievent->sock; + uvreq = ievent->req; + + if (sock->write_timeout == 0) { + sock->write_timeout = + (atomic_load(&sock->keepalive) + ? atomic_load(&sock->mgr->keepalive) + : atomic_load(&sock->mgr->idle)); + } + + uv_buf_t bufs[2] = { { .base = uvreq->tcplen, .len = 2 }, + { .base = uvreq->uvbuf.base, + .len = uvreq->uvbuf.len } }; + + if (isc__nmsocket_closing(sock)) { + result = ISC_R_CANCELED; + goto fail; + } + + r = uv_try_write(&sock->uv_handle.stream, bufs, nbufs); + + if (r == (int)(bufs[0].len + bufs[1].len)) { + /* Wrote everything */ + isc__nm_sendcb(sock, uvreq, ISC_R_SUCCESS, true); + return; + } + + if (r == 1) { + /* Partial write of DNSMSG length */ + bufs[0].base = uvreq->tcplen + 1; + bufs[0].len = 1; + } else if (r > 0) { + /* Partial write of DNSMSG */ + nbufs = 1; + bufs[0].base = uvreq->uvbuf.base + (r - 2); + bufs[0].len = uvreq->uvbuf.len - (r - 2); + } else if (r == UV_ENOSYS || r == UV_EAGAIN) { + /* uv_try_write not supported, send asynchronously */ + } else { + /* error sending data */ + result = isc__nm_uverr2result(r); + goto fail; + } + + r = uv_write(&uvreq->uv_req.write, &sock->uv_handle.stream, bufs, nbufs, + tcpdns_send_cb); + if (r < 0) { + result = isc__nm_uverr2result(r); + goto fail; + } + + isc_nm_timer_create(uvreq->handle, isc__nmsocket_writetimeout_cb, uvreq, + &uvreq->timer); + if (sock->write_timeout > 0) { + isc_nm_timer_start(uvreq->timer, sock->write_timeout); + } + + return; +fail: + isc__nm_incstats(sock, STATID_SENDFAIL); + isc__nm_failed_send_cb(sock, uvreq, result); +} + +static void +tcpdns_stop_cb(uv_handle_t *handle) { + isc_nmsocket_t *sock = uv_handle_get_data(handle); + + REQUIRE(VALID_NMSOCK(sock)); + REQUIRE(sock->tid == isc_nm_tid()); + REQUIRE(atomic_load(&sock->closing)); + + uv_handle_set_data(handle, NULL); + + if (!atomic_compare_exchange_strong(&sock->closed, &(bool){ false }, + true)) + { + UNREACHABLE(); + } + + isc__nm_incstats(sock, STATID_CLOSE); + + atomic_store(&sock->listening, false); + + isc__nmsocket_detach(&sock); +} + +static void +tcpdns_close_sock(isc_nmsocket_t *sock) { + REQUIRE(VALID_NMSOCK(sock)); + REQUIRE(sock->tid == isc_nm_tid()); + REQUIRE(atomic_load(&sock->closing)); + + if (!atomic_compare_exchange_strong(&sock->closed, &(bool){ false }, + true)) + { + UNREACHABLE(); + } + + isc__nm_incstats(sock, STATID_CLOSE); + + if (sock->server != NULL) { + isc__nmsocket_detach(&sock->server); + } + + atomic_store(&sock->connected, false); + + isc__nmsocket_prep_destroy(sock); +} + +static void +tcpdns_close_cb(uv_handle_t *handle) { + isc_nmsocket_t *sock = uv_handle_get_data(handle); + + uv_handle_set_data(handle, NULL); + + tcpdns_close_sock(sock); +} + +static void +read_timer_close_cb(uv_handle_t *timer) { + isc_nmsocket_t *sock = uv_handle_get_data(timer); + uv_handle_set_data(timer, NULL); + + REQUIRE(VALID_NMSOCK(sock)); + + if (sock->parent) { + uv_close(&sock->uv_handle.handle, tcpdns_stop_cb); + } else if (uv_is_closing(&sock->uv_handle.handle)) { + tcpdns_close_sock(sock); + } else { + uv_close(&sock->uv_handle.handle, tcpdns_close_cb); + } +} + +static void +stop_tcpdns_child(isc_nmsocket_t *sock) { + REQUIRE(sock->type == isc_nm_tcpdnssocket); + REQUIRE(sock->tid == isc_nm_tid()); + + if (!atomic_compare_exchange_strong(&sock->closing, &(bool){ false }, + true)) + { + return; + } + + tcpdns_close_direct(sock); + + atomic_fetch_sub(&sock->parent->rchildren, 1); + + isc_barrier_wait(&sock->parent->stoplistening); +} + +static void +stop_tcpdns_parent(isc_nmsocket_t *sock) { + isc_nmsocket_t *csock = NULL; + + REQUIRE(VALID_NMSOCK(sock)); + REQUIRE(sock->tid == isc_nm_tid()); + REQUIRE(sock->type == isc_nm_tcpdnslistener); + + isc_barrier_init(&sock->stoplistening, sock->nchildren); + + for (size_t i = 0; i < sock->nchildren; i++) { + csock = &sock->children[i]; + REQUIRE(VALID_NMSOCK(csock)); + + if ((int)i == isc_nm_tid()) { + /* + * We need to schedule closing the other sockets first + */ + continue; + } + + atomic_store(&csock->active, false); + enqueue_stoplistening(csock); + } + + csock = &sock->children[isc_nm_tid()]; + atomic_store(&csock->active, false); + stop_tcpdns_child(csock); + + atomic_store(&sock->closed, true); + isc__nmsocket_prep_destroy(sock); +} + +static void +tcpdns_close_direct(isc_nmsocket_t *sock) { + REQUIRE(VALID_NMSOCK(sock)); + REQUIRE(sock->tid == isc_nm_tid()); + REQUIRE(atomic_load(&sock->closing)); + + if (sock->quota != NULL) { + isc_quota_detach(&sock->quota); + } + + if (sock->recv_handle != NULL) { + isc_nmhandle_detach(&sock->recv_handle); + } + + isc__nmsocket_timer_stop(sock); + isc__nm_stop_reading(sock); + + uv_handle_set_data((uv_handle_t *)&sock->read_timer, sock); + uv_close((uv_handle_t *)&sock->read_timer, read_timer_close_cb); +} + +void +isc__nm_tcpdns_close(isc_nmsocket_t *sock) { + REQUIRE(VALID_NMSOCK(sock)); + REQUIRE(sock->type == isc_nm_tcpdnssocket); + REQUIRE(!isc__nmsocket_active(sock)); + + if (!atomic_compare_exchange_strong(&sock->closing, &(bool){ false }, + true)) + { + return; + } + + if (sock->tid == isc_nm_tid()) { + tcpdns_close_direct(sock); + } else { + /* + * We need to create an event and pass it using async channel + */ + isc__netievent_tcpdnsclose_t *ievent = + isc__nm_get_netievent_tcpdnsclose(sock->mgr, sock); + + isc__nm_enqueue_ievent(&sock->mgr->workers[sock->tid], + (isc__netievent_t *)ievent); + } +} + +void +isc__nm_async_tcpdnsclose(isc__networker_t *worker, isc__netievent_t *ev0) { + isc__netievent_tcpdnsclose_t *ievent = + (isc__netievent_tcpdnsclose_t *)ev0; + isc_nmsocket_t *sock = ievent->sock; + + UNUSED(worker); + + REQUIRE(VALID_NMSOCK(sock)); + REQUIRE(sock->tid == isc_nm_tid()); + + tcpdns_close_direct(sock); +} + +static void +tcpdns_close_connect_cb(uv_handle_t *handle) { + isc_nmsocket_t *sock = uv_handle_get_data(handle); + + REQUIRE(VALID_NMSOCK(sock)); + + REQUIRE(isc__nm_in_netthread()); + REQUIRE(sock->tid == isc_nm_tid()); + + isc__nmsocket_prep_destroy(sock); + isc__nmsocket_detach(&sock); +} + +void +isc__nm_tcpdns_shutdown(isc_nmsocket_t *sock) { + REQUIRE(VALID_NMSOCK(sock)); + REQUIRE(sock->tid == isc_nm_tid()); + REQUIRE(sock->type == isc_nm_tcpdnssocket); + + /* + * If the socket is active, mark it inactive and + * continue. If it isn't active, stop now. + */ + if (!isc__nmsocket_deactivate(sock)) { + return; + } + + if (atomic_load(&sock->accepting)) { + return; + } + + if (atomic_load(&sock->connecting)) { + isc_nmsocket_t *tsock = NULL; + isc__nmsocket_attach(sock, &tsock); + uv_close(&sock->uv_handle.handle, tcpdns_close_connect_cb); + return; + } + + if (sock->statichandle != NULL) { + if (isc__nm_closing(sock)) { + isc__nm_failed_read_cb(sock, ISC_R_SHUTTINGDOWN, false); + } else { + isc__nm_failed_read_cb(sock, ISC_R_CANCELED, false); + } + return; + } + + /* + * Otherwise, we just send the socket to abyss... + */ + if (sock->parent == NULL) { + isc__nmsocket_prep_destroy(sock); + } +} + +void +isc__nm_tcpdns_cancelread(isc_nmhandle_t *handle) { + isc_nmsocket_t *sock = NULL; + isc__netievent_tcpdnscancel_t *ievent = NULL; + + REQUIRE(VALID_NMHANDLE(handle)); + + sock = handle->sock; + + REQUIRE(VALID_NMSOCK(sock)); + REQUIRE(sock->type == isc_nm_tcpdnssocket); + + ievent = isc__nm_get_netievent_tcpdnscancel(sock->mgr, sock, handle); + isc__nm_enqueue_ievent(&sock->mgr->workers[sock->tid], + (isc__netievent_t *)ievent); +} + +void +isc__nm_async_tcpdnscancel(isc__networker_t *worker, isc__netievent_t *ev0) { + isc__netievent_tcpdnscancel_t *ievent = + (isc__netievent_tcpdnscancel_t *)ev0; + isc_nmsocket_t *sock = ievent->sock; + + UNUSED(worker); + + REQUIRE(VALID_NMSOCK(sock)); + REQUIRE(sock->tid == isc_nm_tid()); + + isc__nm_failed_read_cb(sock, ISC_R_EOF, false); +} |