diff options
Diffstat (limited to '')
| -rw-r--r-- | src/proto_tcp.c | 834 |
1 files changed, 834 insertions, 0 deletions
diff --git a/src/proto_tcp.c b/src/proto_tcp.c new file mode 100644 index 0000000..45ce27f --- /dev/null +++ b/src/proto_tcp.c @@ -0,0 +1,834 @@ +/* + * AF_INET/AF_INET6 SOCK_STREAM protocol layer (tcp) + * + * Copyright 2000-2013 Willy Tarreau <w@1wt.eu> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + */ + +#include <ctype.h> +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <time.h> + +#include <sys/param.h> +#include <sys/socket.h> +#include <sys/types.h> + +#include <netinet/tcp.h> +#include <netinet/in.h> + +#include <haproxy/api.h> +#include <haproxy/arg.h> +#include <haproxy/connection.h> +#include <haproxy/errors.h> +#include <haproxy/fd.h> +#include <haproxy/global.h> +#include <haproxy/list.h> +#include <haproxy/listener.h> +#include <haproxy/log.h> +#include <haproxy/namespace.h> +#include <haproxy/port_range.h> +#include <haproxy/proto_tcp.h> +#include <haproxy/protocol.h> +#include <haproxy/proxy-t.h> +#include <haproxy/sock.h> +#include <haproxy/sock_inet.h> +#include <haproxy/tools.h> + + +static int tcp_bind_listener(struct listener *listener, char *errmsg, int errlen); +static int tcp_suspend_receiver(struct receiver *rx); +static int tcp_resume_receiver(struct receiver *rx); +static void tcp_enable_listener(struct listener *listener); +static void tcp_disable_listener(struct listener *listener); + +/* Note: must not be declared <const> as its list will be overwritten */ +struct protocol proto_tcpv4 = { + .name = "tcpv4", + + /* connection layer */ + .xprt_type = PROTO_TYPE_STREAM, + .listen = tcp_bind_listener, + .enable = tcp_enable_listener, + .disable = tcp_disable_listener, + .add = default_add_listener, + .unbind = default_unbind_listener, + .suspend = default_suspend_listener, + .resume = default_resume_listener, + .accept_conn = sock_accept_conn, + .ctrl_init = sock_conn_ctrl_init, + .ctrl_close = sock_conn_ctrl_close, + .connect = tcp_connect_server, + .drain = sock_drain, + .check_events = sock_check_events, + .ignore_events = sock_ignore_events, + + /* binding layer */ + .rx_suspend = tcp_suspend_receiver, + .rx_resume = tcp_resume_receiver, + + /* address family */ + .fam = &proto_fam_inet4, + + /* socket layer */ + .proto_type = PROTO_TYPE_STREAM, + .sock_type = SOCK_STREAM, + .sock_prot = IPPROTO_TCP, + .rx_enable = sock_enable, + .rx_disable = sock_disable, + .rx_unbind = sock_unbind, + .rx_listening = sock_accepting_conn, + .default_iocb = sock_accept_iocb, + .receivers = LIST_HEAD_INIT(proto_tcpv4.receivers), + .nb_receivers = 0, +#ifdef SO_REUSEPORT + .flags = PROTO_F_REUSEPORT_SUPPORTED, +#endif +}; + +INITCALL1(STG_REGISTER, protocol_register, &proto_tcpv4); + +/* Note: must not be declared <const> as its list will be overwritten */ +struct protocol proto_tcpv6 = { + .name = "tcpv6", + + /* connection layer */ + .xprt_type = PROTO_TYPE_STREAM, + .listen = tcp_bind_listener, + .enable = tcp_enable_listener, + .disable = tcp_disable_listener, + .add = default_add_listener, + .unbind = default_unbind_listener, + .suspend = default_suspend_listener, + .resume = default_resume_listener, + .accept_conn = sock_accept_conn, + .ctrl_init = sock_conn_ctrl_init, + .ctrl_close = sock_conn_ctrl_close, + .connect = tcp_connect_server, + .drain = sock_drain, + .check_events = sock_check_events, + .ignore_events = sock_ignore_events, + + /* binding layer */ + .rx_suspend = tcp_suspend_receiver, + .rx_resume = tcp_resume_receiver, + + /* address family */ + .fam = &proto_fam_inet6, + + /* socket layer */ + .proto_type = PROTO_TYPE_STREAM, + .sock_type = SOCK_STREAM, + .sock_prot = IPPROTO_TCP, + .rx_enable = sock_enable, + .rx_disable = sock_disable, + .rx_unbind = sock_unbind, + .rx_listening = sock_accepting_conn, + .default_iocb = sock_accept_iocb, + .receivers = LIST_HEAD_INIT(proto_tcpv6.receivers), + .nb_receivers = 0, +#ifdef SO_REUSEPORT + .flags = PROTO_F_REUSEPORT_SUPPORTED, +#endif +}; + +INITCALL1(STG_REGISTER, protocol_register, &proto_tcpv6); + +/* Binds ipv4/ipv6 address <local> to socket <fd>, unless <flags> is set, in which + * case we try to bind <remote>. <flags> is a 2-bit field consisting of : + * - 0 : ignore remote address (may even be a NULL pointer) + * - 1 : use provided address + * - 2 : use provided port + * - 3 : use both + * + * The function supports multiple foreign binding methods : + * - linux_tproxy: we directly bind to the foreign address + * The second one can be used as a fallback for the first one. + * This function returns 0 when everything's OK, 1 if it could not bind, to the + * local address, 2 if it could not bind to the foreign address. + */ +int tcp_bind_socket(int fd, int flags, struct sockaddr_storage *local, struct sockaddr_storage *remote) +{ + struct sockaddr_storage bind_addr; + int foreign_ok = 0; + int ret; + static THREAD_LOCAL int ip_transp_working = 1; + static THREAD_LOCAL int ip6_transp_working = 1; + + switch (local->ss_family) { + case AF_INET: + if (flags && ip_transp_working) { + /* This deserves some explanation. Some platforms will support + * multiple combinations of certain methods, so we try the + * supported ones until one succeeds. + */ + if (sock_inet4_make_foreign(fd)) + foreign_ok = 1; + else + ip_transp_working = 0; + } + break; + case AF_INET6: + if (flags && ip6_transp_working) { + if (sock_inet6_make_foreign(fd)) + foreign_ok = 1; + else + ip6_transp_working = 0; + } + break; + } + + if (flags) { + memset(&bind_addr, 0, sizeof(bind_addr)); + bind_addr.ss_family = remote->ss_family; + switch (remote->ss_family) { + case AF_INET: + if (flags & 1) + ((struct sockaddr_in *)&bind_addr)->sin_addr = ((struct sockaddr_in *)remote)->sin_addr; + if (flags & 2) + ((struct sockaddr_in *)&bind_addr)->sin_port = ((struct sockaddr_in *)remote)->sin_port; + break; + case AF_INET6: + if (flags & 1) + ((struct sockaddr_in6 *)&bind_addr)->sin6_addr = ((struct sockaddr_in6 *)remote)->sin6_addr; + if (flags & 2) + ((struct sockaddr_in6 *)&bind_addr)->sin6_port = ((struct sockaddr_in6 *)remote)->sin6_port; + break; + default: + /* we don't want to try to bind to an unknown address family */ + foreign_ok = 0; + } + } + + setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)); + if (foreign_ok) { + if (is_inet_addr(&bind_addr)) { + ret = bind(fd, (struct sockaddr *)&bind_addr, get_addr_len(&bind_addr)); + if (ret < 0) + return 2; + } + } + else { + if (is_inet_addr(local)) { + ret = bind(fd, (struct sockaddr *)local, get_addr_len(local)); + if (ret < 0) + return 1; + } + } + + if (!flags) + return 0; + + if (!foreign_ok) + /* we could not bind to a foreign address */ + return 2; + + return 0; +} + +/* + * This function initiates a TCP connection establishment to the target assigned + * to connection <conn> using (si->{target,dst}). A source address may be + * pointed to by conn->src in case of transparent proxying. Normal source + * bind addresses are still determined locally (due to the possible need of a + * source port). conn->target may point either to a valid server or to a backend, + * depending on conn->target. Only OBJ_TYPE_PROXY and OBJ_TYPE_SERVER are + * supported. The <data> parameter is a boolean indicating whether there are data + * waiting for being sent or not, in order to adjust data write polling and on + * some platforms, the ability to avoid an empty initial ACK. The <flags> argument + * allows the caller to force using a delayed ACK when establishing the connection + * - 0 = no delayed ACK unless data are advertised and backend has tcp-smart-connect + * - CONNECT_DELACK_SMART_CONNECT = delayed ACK if backend has tcp-smart-connect, regardless of data + * - CONNECT_DELACK_ALWAYS = delayed ACK regardless of backend options + * + * Note that a pending send_proxy message accounts for data. + * + * It can return one of : + * - SF_ERR_NONE if everything's OK + * - SF_ERR_SRVTO if there are no more servers + * - SF_ERR_SRVCL if the connection was refused by the server + * - SF_ERR_PRXCOND if the connection has been limited by the proxy (maxconn) + * - SF_ERR_RESOURCE if a system resource is lacking (eg: fd limits, ports, ...) + * - SF_ERR_INTERNAL for any other purely internal errors + * Additionally, in the case of SF_ERR_RESOURCE, an emergency log will be emitted. + * + * The connection's fd is inserted only when SF_ERR_NONE is returned, otherwise + * it's invalid and the caller has nothing to do. + */ + +int tcp_connect_server(struct connection *conn, int flags) +{ + int fd; + struct server *srv; + struct proxy *be; + struct conn_src *src; + int use_fastopen = 0; + struct sockaddr_storage *addr; + + BUG_ON(!conn->dst); + + conn->flags |= CO_FL_WAIT_L4_CONN; /* connection in progress */ + + switch (obj_type(conn->target)) { + case OBJ_TYPE_PROXY: + be = __objt_proxy(conn->target); + srv = NULL; + break; + case OBJ_TYPE_SERVER: + srv = __objt_server(conn->target); + be = srv->proxy; + /* Make sure we check that we have data before activating + * TFO, or we could trigger a kernel issue whereby after + * a successful connect() == 0, any subsequent connect() + * will return EINPROGRESS instead of EISCONN. + */ + use_fastopen = (srv->flags & SRV_F_FASTOPEN) && + ((flags & (CONNECT_CAN_USE_TFO | CONNECT_HAS_DATA)) == + (CONNECT_CAN_USE_TFO | CONNECT_HAS_DATA)); + break; + default: + conn->flags |= CO_FL_ERROR; + return SF_ERR_INTERNAL; + } + + fd = conn->handle.fd = sock_create_server_socket(conn); + + if (fd == -1) { + qfprintf(stderr, "Cannot get a server socket.\n"); + + if (errno == ENFILE) { + conn->err_code = CO_ER_SYS_FDLIM; + send_log(be, LOG_EMERG, + "Proxy %s reached system FD limit (maxsock=%d). Please check system tunables.\n", + be->id, global.maxsock); + } + else if (errno == EMFILE) { + conn->err_code = CO_ER_PROC_FDLIM; + send_log(be, LOG_EMERG, + "Proxy %s reached process FD limit (maxsock=%d). Please check 'ulimit-n' and restart.\n", + be->id, global.maxsock); + } + else if (errno == ENOBUFS || errno == ENOMEM) { + conn->err_code = CO_ER_SYS_MEMLIM; + send_log(be, LOG_EMERG, + "Proxy %s reached system memory limit (maxsock=%d). Please check system tunables.\n", + be->id, global.maxsock); + } + else if (errno == EAFNOSUPPORT || errno == EPROTONOSUPPORT) { + conn->err_code = CO_ER_NOPROTO; + } + else + conn->err_code = CO_ER_SOCK_ERR; + + /* this is a resource error */ + conn->flags |= CO_FL_ERROR; + return SF_ERR_RESOURCE; + } + + if (fd >= global.maxsock) { + /* do not log anything there, it's a normal condition when this option + * is used to serialize connections to a server ! + */ + ha_alert("socket(): not enough free sockets. Raise -n argument. Giving up.\n"); + close(fd); + conn->err_code = CO_ER_CONF_FDLIM; + conn->flags |= CO_FL_ERROR; + return SF_ERR_PRXCOND; /* it is a configuration limit */ + } + + if (fd_set_nonblock(fd) == -1 || + (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &one, sizeof(one)) == -1)) { + qfprintf(stderr,"Cannot set client socket to non blocking mode.\n"); + close(fd); + conn->err_code = CO_ER_SOCK_ERR; + conn->flags |= CO_FL_ERROR; + return SF_ERR_INTERNAL; + } + + if (master == 1 && fd_set_cloexec(fd) == -1) { + ha_alert("Cannot set CLOEXEC on client socket.\n"); + close(fd); + conn->err_code = CO_ER_SOCK_ERR; + conn->flags |= CO_FL_ERROR; + return SF_ERR_INTERNAL; + } + + if (be->options & PR_O_TCP_SRV_KA) { + setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, &one, sizeof(one)); + +#ifdef TCP_KEEPCNT + if (be->srvtcpka_cnt) + setsockopt(fd, IPPROTO_TCP, TCP_KEEPCNT, &be->srvtcpka_cnt, sizeof(be->srvtcpka_cnt)); +#endif + +#ifdef TCP_KEEPIDLE + if (be->srvtcpka_idle) + setsockopt(fd, IPPROTO_TCP, TCP_KEEPIDLE, &be->srvtcpka_idle, sizeof(be->srvtcpka_idle)); +#endif + +#ifdef TCP_KEEPINTVL + if (be->srvtcpka_intvl) + setsockopt(fd, IPPROTO_TCP, TCP_KEEPINTVL, &be->srvtcpka_intvl, sizeof(be->srvtcpka_intvl)); +#endif + } + + /* allow specific binding : + * - server-specific at first + * - proxy-specific next + */ + if (srv && srv->conn_src.opts & CO_SRC_BIND) + src = &srv->conn_src; + else if (be->conn_src.opts & CO_SRC_BIND) + src = &be->conn_src; + else + src = NULL; + + if (src) { + int ret, flags = 0; + + if (conn->src && is_inet_addr(conn->src)) { + switch (src->opts & CO_SRC_TPROXY_MASK) { + case CO_SRC_TPROXY_CLI: + case CO_SRC_TPROXY_ADDR: + flags = 3; + break; + case CO_SRC_TPROXY_CIP: + case CO_SRC_TPROXY_DYN: + flags = 1; + break; + } + } + +#ifdef SO_BINDTODEVICE + /* Note: this might fail if not CAP_NET_RAW */ + if (src->iface_name) + setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, src->iface_name, src->iface_len + 1); +#endif + + if (src->sport_range) { + int attempts = 10; /* should be more than enough to find a spare port */ + struct sockaddr_storage sa; + + ret = 1; + memcpy(&sa, &src->source_addr, sizeof(sa)); + + do { + /* note: in case of retry, we may have to release a previously + * allocated port, hence this loop's construct. + */ + port_range_release_port(fdinfo[fd].port_range, fdinfo[fd].local_port); + fdinfo[fd].port_range = NULL; + + if (!attempts) + break; + attempts--; + + fdinfo[fd].local_port = port_range_alloc_port(src->sport_range); + if (!fdinfo[fd].local_port) { + conn->err_code = CO_ER_PORT_RANGE; + break; + } + + fdinfo[fd].port_range = src->sport_range; + set_host_port(&sa, fdinfo[fd].local_port); + + ret = tcp_bind_socket(fd, flags, &sa, conn->src); + if (ret != 0) + conn->err_code = CO_ER_CANT_BIND; + } while (ret != 0); /* binding NOK */ + } + else { +#ifdef IP_BIND_ADDRESS_NO_PORT + static THREAD_LOCAL int bind_address_no_port = 1; + setsockopt(fd, IPPROTO_IP, IP_BIND_ADDRESS_NO_PORT, (const void *) &bind_address_no_port, sizeof(int)); +#endif + ret = tcp_bind_socket(fd, flags, &src->source_addr, conn->src); + if (ret != 0) + conn->err_code = CO_ER_CANT_BIND; + } + + if (unlikely(ret != 0)) { + port_range_release_port(fdinfo[fd].port_range, fdinfo[fd].local_port); + fdinfo[fd].port_range = NULL; + close(fd); + + if (ret == 1) { + ha_alert("Cannot bind to source address before connect() for backend %s. Aborting.\n", + be->id); + send_log(be, LOG_EMERG, + "Cannot bind to source address before connect() for backend %s.\n", + be->id); + } else { + ha_alert("Cannot bind to tproxy source address before connect() for backend %s. Aborting.\n", + be->id); + send_log(be, LOG_EMERG, + "Cannot bind to tproxy source address before connect() for backend %s.\n", + be->id); + } + conn->flags |= CO_FL_ERROR; + return SF_ERR_RESOURCE; + } + } + +#if defined(TCP_QUICKACK) + /* disabling tcp quick ack now allows the first request to leave the + * machine with the first ACK. We only do this if there are pending + * data in the buffer. + */ + if (flags & (CONNECT_DELACK_ALWAYS) || + ((flags & CONNECT_DELACK_SMART_CONNECT || + (flags & CONNECT_HAS_DATA) || conn->send_proxy_ofs) && + (be->options2 & PR_O2_SMARTCON))) + setsockopt(fd, IPPROTO_TCP, TCP_QUICKACK, &zero, sizeof(zero)); +#endif + +#ifdef TCP_USER_TIMEOUT + /* there is not much more we can do here when it fails, it's still minor */ + if (srv && srv->tcp_ut) + setsockopt(fd, IPPROTO_TCP, TCP_USER_TIMEOUT, &srv->tcp_ut, sizeof(srv->tcp_ut)); +#endif + + if (use_fastopen) { +#if defined(TCP_FASTOPEN_CONNECT) + setsockopt(fd, IPPROTO_TCP, TCP_FASTOPEN_CONNECT, &one, sizeof(one)); +#endif + } + if (global.tune.server_sndbuf) + setsockopt(fd, SOL_SOCKET, SO_SNDBUF, &global.tune.server_sndbuf, sizeof(global.tune.server_sndbuf)); + + if (global.tune.server_rcvbuf) + setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &global.tune.server_rcvbuf, sizeof(global.tune.server_rcvbuf)); + + addr = (conn->flags & CO_FL_SOCKS4) ? &srv->socks4_addr : conn->dst; + if (connect(fd, (const struct sockaddr *)addr, get_addr_len(addr)) == -1) { + if (errno == EINPROGRESS || errno == EALREADY) { + /* common case, let's wait for connect status */ + conn->flags |= CO_FL_WAIT_L4_CONN; + } + else if (errno == EISCONN) { + /* should normally not happen but if so, indicates that it's OK */ + conn->flags &= ~CO_FL_WAIT_L4_CONN; + } + else if (errno == EAGAIN || errno == EWOULDBLOCK || errno == EADDRINUSE || errno == EADDRNOTAVAIL) { + char *msg; + if (errno == EAGAIN || errno == EWOULDBLOCK || errno == EADDRNOTAVAIL) { + msg = "no free ports"; + conn->err_code = CO_ER_FREE_PORTS; + } + else { + msg = "local address already in use"; + conn->err_code = CO_ER_ADDR_INUSE; + } + + qfprintf(stderr,"Connect() failed for backend %s: %s.\n", be->id, msg); + port_range_release_port(fdinfo[fd].port_range, fdinfo[fd].local_port); + fdinfo[fd].port_range = NULL; + close(fd); + send_log(be, LOG_ERR, "Connect() failed for backend %s: %s.\n", be->id, msg); + conn->flags |= CO_FL_ERROR; + return SF_ERR_RESOURCE; + } else if (errno == ETIMEDOUT) { + //qfprintf(stderr,"Connect(): ETIMEDOUT"); + port_range_release_port(fdinfo[fd].port_range, fdinfo[fd].local_port); + fdinfo[fd].port_range = NULL; + close(fd); + conn->err_code = CO_ER_SOCK_ERR; + conn->flags |= CO_FL_ERROR; + return SF_ERR_SRVTO; + } else { + // (errno == ECONNREFUSED || errno == ENETUNREACH || errno == EACCES || errno == EPERM) + //qfprintf(stderr,"Connect(): %d", errno); + port_range_release_port(fdinfo[fd].port_range, fdinfo[fd].local_port); + fdinfo[fd].port_range = NULL; + close(fd); + conn->err_code = CO_ER_SOCK_ERR; + conn->flags |= CO_FL_ERROR; + return SF_ERR_SRVCL; + } + } + else { + /* connect() == 0, this is great! */ + conn->flags &= ~CO_FL_WAIT_L4_CONN; + } + + conn_ctrl_init(conn); /* registers the FD */ + HA_ATOMIC_OR(&fdtab[fd].state, FD_LINGER_RISK); /* close hard if needed */ + + if (conn->flags & CO_FL_WAIT_L4_CONN) { + fd_want_send(fd); + fd_cant_send(fd); + fd_cant_recv(fd); + } + + return SF_ERR_NONE; /* connection is OK */ +} + +/* This function tries to bind a TCPv4/v6 listener. It may return a warning or + * an error message in <errmsg> if the message is at most <errlen> bytes long + * (including '\0'). Note that <errmsg> may be NULL if <errlen> is also zero. + * The return value is composed from ERR_ABORT, ERR_WARN, + * ERR_ALERT, ERR_RETRYABLE and ERR_FATAL. ERR_NONE indicates that everything + * was alright and that no message was returned. ERR_RETRYABLE means that an + * error occurred but that it may vanish after a retry (eg: port in use), and + * ERR_FATAL indicates a non-fixable error. ERR_WARN and ERR_ALERT do not alter + * the meaning of the error, but just indicate that a message is present which + * should be displayed with the respective level. Last, ERR_ABORT indicates + * that it's pointless to try to start other listeners. No error message is + * returned if errlen is NULL. + */ +int tcp_bind_listener(struct listener *listener, char *errmsg, int errlen) +{ + int fd, err; + int ready; + struct buffer *msg = alloc_trash_chunk(); + + err = ERR_NONE; + + if (!msg) { + if (errlen) + snprintf(errmsg, errlen, "out of memory"); + return ERR_ALERT | ERR_FATAL; + } + + /* ensure we never return garbage */ + if (errlen) + *errmsg = 0; + + if (listener->state != LI_ASSIGNED) + return ERR_NONE; /* already bound */ + + if (!(listener->rx.flags & RX_F_BOUND)) { + chunk_appendf(msg, "%sreceiving socket not bound", msg->data ? ", " : ""); + goto tcp_return; + } + + if (listener->rx.flags & RX_F_MUST_DUP) + goto done; + + fd = listener->rx.fd; + + if (listener->bind_conf->options & BC_O_NOLINGER) + setsockopt(fd, SOL_SOCKET, SO_LINGER, &nolinger, sizeof(struct linger)); + else { + struct linger tmplinger; + socklen_t len = sizeof(tmplinger); + if (getsockopt(fd, SOL_SOCKET, SO_LINGER, &tmplinger, &len) == 0 && + (tmplinger.l_onoff == 1 || tmplinger.l_linger == 0)) { + tmplinger.l_onoff = 0; + tmplinger.l_linger = 0; + setsockopt(fd, SOL_SOCKET, SO_LINGER, &tmplinger, + sizeof(tmplinger)); + } + } + +#if defined(TCP_MAXSEG) + if (listener->bind_conf->maxseg > 0) { + if (setsockopt(fd, IPPROTO_TCP, TCP_MAXSEG, + &listener->bind_conf->maxseg, sizeof(listener->bind_conf->maxseg)) == -1) { + chunk_appendf(msg, "%scannot set MSS to %d", msg->data ? ", " : "", listener->bind_conf->maxseg); + err |= ERR_WARN; + } + } else { + /* we may want to try to restore the default MSS if the socket was inherited */ + int tmpmaxseg = -1; + int defaultmss; + socklen_t len = sizeof(tmpmaxseg); + + if (listener->rx.addr.ss_family == AF_INET) + defaultmss = sock_inet_tcp_maxseg_default; + else + defaultmss = sock_inet6_tcp_maxseg_default; + + getsockopt(fd, IPPROTO_TCP, TCP_MAXSEG, &tmpmaxseg, &len); + if (defaultmss > 0 && + tmpmaxseg != defaultmss && + setsockopt(fd, IPPROTO_TCP, TCP_MAXSEG, &defaultmss, sizeof(defaultmss)) == -1) { + chunk_appendf(msg, "%scannot set MSS to %d", msg->data ? ", " : "", defaultmss); + err |= ERR_WARN; + } + } +#endif +#if defined(TCP_USER_TIMEOUT) + if (listener->bind_conf->tcp_ut) { + if (setsockopt(fd, IPPROTO_TCP, TCP_USER_TIMEOUT, + &listener->bind_conf->tcp_ut, sizeof(listener->bind_conf->tcp_ut)) == -1) { + chunk_appendf(msg, "%scannot set TCP User Timeout", msg->data ? ", " : ""); + err |= ERR_WARN; + } + } else + setsockopt(fd, IPPROTO_TCP, TCP_USER_TIMEOUT, &zero, + sizeof(zero)); +#endif +#if defined(TCP_DEFER_ACCEPT) + if (listener->bind_conf->options & BC_O_DEF_ACCEPT) { + /* defer accept by up to one second */ + int accept_delay = 1; + if (setsockopt(fd, IPPROTO_TCP, TCP_DEFER_ACCEPT, &accept_delay, sizeof(accept_delay)) == -1) { + chunk_appendf(msg, "%scannot enable DEFER_ACCEPT", msg->data ? ", " : ""); + err |= ERR_WARN; + } + } else + setsockopt(fd, IPPROTO_TCP, TCP_DEFER_ACCEPT, &zero, + sizeof(zero)); +#endif +#if defined(TCP_FASTOPEN) + if (listener->bind_conf->options & BC_O_TCP_FO) { + /* TFO needs a queue length, let's use the configured backlog */ + int qlen = listener_backlog(listener); + if (setsockopt(fd, IPPROTO_TCP, TCP_FASTOPEN, &qlen, sizeof(qlen)) == -1) { + chunk_appendf(msg, "%scannot enable TCP_FASTOPEN", msg->data ? ", " : ""); + err |= ERR_WARN; + } + } else { + socklen_t len; + int qlen; + len = sizeof(qlen); + /* Only disable fast open if it was enabled, we don't want + * the kernel to create a fast open queue if there's none. + */ + if (getsockopt(fd, IPPROTO_TCP, TCP_FASTOPEN, &qlen, &len) == 0 && + qlen != 0) { + if (setsockopt(fd, IPPROTO_TCP, TCP_FASTOPEN, &zero, + sizeof(zero)) == -1) { + chunk_appendf(msg, "%scannot disable TCP_FASTOPEN", msg->data ? ", " : ""); + err |= ERR_WARN; + } + } + } +#endif + + ready = sock_accepting_conn(&listener->rx) > 0; + + if (!ready && /* only listen if not already done by external process */ + listen(fd, listener_backlog(listener)) == -1) { + err |= ERR_RETRYABLE | ERR_ALERT; + chunk_appendf(msg, "%scannot listen to socket", msg->data ? ", " : ""); + goto tcp_close_return; + } + +#if !defined(TCP_DEFER_ACCEPT) && defined(SO_ACCEPTFILTER) + /* the socket needs to listen first */ + if (listener->bind_conf->options & BC_O_DEF_ACCEPT) { + struct accept_filter_arg accept; + memset(&accept, 0, sizeof(accept)); + strlcpy2(accept.af_name, "dataready", sizeof(accept.af_name)); + if (setsockopt(fd, SOL_SOCKET, SO_ACCEPTFILTER, &accept, sizeof(accept)) == -1) { + chunk_appendf(msg, "%scannot enable ACCEPT_FILTER", msg->data ? ", " : ""); + err |= ERR_WARN; + } + } +#endif +#if defined(TCP_QUICKACK) + if (listener->bind_conf->options & BC_O_NOQUICKACK) + setsockopt(fd, IPPROTO_TCP, TCP_QUICKACK, &zero, sizeof(zero)); + else + setsockopt(fd, IPPROTO_TCP, TCP_QUICKACK, &one, sizeof(one)); +#endif + + done: + /* the socket is ready */ + listener_set_state(listener, LI_LISTEN); + goto tcp_return; + + tcp_close_return: + free_trash_chunk(msg); + msg = NULL; + close(fd); + tcp_return: + if (msg && errlen && msg->data) { + char pn[INET6_ADDRSTRLEN]; + + addr_to_str(&listener->rx.addr, pn, sizeof(pn)); + snprintf(errmsg, errlen, "%s for [%s:%d]", msg->area, pn, get_host_port(&listener->rx.addr)); + } + free_trash_chunk(msg); + msg = NULL; + return err; +} + +/* Enable receipt of incoming connections for listener <l>. The receiver must + * still be valid. + */ +static void tcp_enable_listener(struct listener *l) +{ + fd_want_recv_safe(l->rx.fd); +} + +/* Disable receipt of incoming connections for listener <l>. The receiver must + * still be valid. + */ +static void tcp_disable_listener(struct listener *l) +{ + fd_stop_recv(l->rx.fd); +} + +/* Suspend a receiver. Returns < 0 in case of failure, 0 if the receiver + * was totally stopped, or > 0 if correctly suspended. Note that inherited FDs + * are neither suspended nor resumed, we only enable/disable polling on them. + */ +static int tcp_suspend_receiver(struct receiver *rx) +{ + const struct sockaddr sa = { .sa_family = AF_UNSPEC }; + int ret; + + /* We never disconnect a shared FD otherwise we'd break it in the + * parent process and any possible subsequent worker inheriting it. + * Thus we just stop receiving from it. + */ + if (rx->flags & RX_F_INHERITED) + goto done; + + if (connect(rx->fd, &sa, sizeof(sa)) < 0) + goto check_already_done; + done: + fd_stop_recv(rx->fd); + return 1; + + check_already_done: + /* in case one of the shutdown() above fails, it might be because we're + * dealing with a socket that is shared with other processes doing the + * same. Let's check if it's still accepting connections. + */ + ret = sock_accepting_conn(rx); + if (ret <= 0) { + /* unrecoverable or paused by another process */ + fd_stop_recv(rx->fd); + return ret == 0; + } + + /* still listening, that's not good */ + return -1; +} + +/* Resume a receiver. Returns < 0 in case of failure, 0 if the receiver + * was totally stopped, or > 0 if correctly resumed. Note that inherited FDs + * are neither suspended nor resumed, we only enable/disable polling on them. + */ +static int tcp_resume_receiver(struct receiver *rx) +{ + struct listener *l = LIST_ELEM(rx, struct listener *, rx); + + if (rx->fd < 0) + return 0; + + if ((rx->flags & RX_F_INHERITED) || listen(rx->fd, listener_backlog(l)) == 0) { + fd_want_recv(l->rx.fd); + return 1; + } + return -1; +} + + +/* + * Local variables: + * c-indent-level: 8 + * c-basic-offset: 8 + * End: + */ |