/* $NetBSD: tcpdns.c,v 1.10.2.2 2024/02/29 12:35:14 martin Exp $ */ /* * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #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->nlisteners); 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->nlisteners; 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); } if (sock->client && !sock->recv_read) { /* * We are not reading data - stop here. */ 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); }