From 097f88088e00923b74bc4c38e67feceb162ba4ef Mon Sep 17 00:00:00 2001 From: Guus Sliepen Date: Sun, 15 Mar 2020 16:08:44 +0100 Subject: [PATCH] Fix the order of socket operations when setting up listening sockets. Commit db8e6e4 caused calls to setsockopt() for setting up socket parameters to be called after the call to bind(). --- src/net.h | 2 - src/net_setup.c | 134 +++++++++++++++++++++++++++++++++++++++-------- src/net_socket.c | 89 ------------------------------- 3 files changed, 113 insertions(+), 112 deletions(-) diff --git a/src/net.h b/src/net.h index 63fb922f..cdb0cca5 100644 --- a/src/net.h +++ b/src/net.h @@ -84,8 +84,6 @@ extern void handle_incoming_vpn_data(struct event_loop_t *loop, void *, int); extern void finish_connecting(struct meshlink_handle *mesh, struct connection_t *); extern void do_outgoing_connection(struct meshlink_handle *mesh, struct outgoing_t *); extern void handle_new_meta_connection(struct event_loop_t *loop, void *, int); -extern bool setup_listen_socket(struct meshlink_handle *mesh, int fd, int sa_family) __attribute__((__warn_unused_result__)); -extern bool setup_vpn_in_socket(struct meshlink_handle *mesh, int fd, int sa_family) __attribute__((__warn_unused_result__)); extern bool send_sptps_data(void *handle, uint8_t type, const void *data, size_t len); extern bool receive_sptps_record(void *handle, uint8_t type, const void *data, uint16_t len) __attribute__((__warn_unused_result__)); extern void send_packet(struct meshlink_handle *mesh, struct node_t *, struct vpn_packet_t *); diff --git a/src/net_setup.c b/src/net_setup.c index 4cff1a5e..d0e45003 100644 --- a/src/net_setup.c +++ b/src/net_setup.c @@ -301,6 +301,117 @@ static bool load_node(meshlink_handle_t *mesh, const char *name, void *priv) { return true; } +static int setup_tcp_listen_socket(meshlink_handle_t *mesh, const struct addrinfo *aip) { + int nfd = socket(aip->ai_family, SOCK_STREAM, IPPROTO_TCP); + + if(nfd == -1) { + return -1; + } + +#ifdef FD_CLOEXEC + fcntl(nfd, F_SETFD, FD_CLOEXEC); +#endif + + int option = 1; + setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, (void *)&option, sizeof(option)); + +#if defined(IPV6_V6ONLY) + + if(aip->ai_family == AF_INET6) { + setsockopt(nfd, IPPROTO_IPV6, IPV6_V6ONLY, (void *)&option, sizeof(option)); + } + +#else +#warning IPV6_V6ONLY not defined +#endif + + if(bind(nfd, aip->ai_addr, aip->ai_addrlen)) { + closesocket(nfd); + return -1; + } + + if(listen(nfd, 3)) { + logger(mesh, MESHLINK_ERROR, "System call `%s' failed: %s", "listen", sockstrerror(sockerrno)); + closesocket(nfd); + return -1; + } + + return nfd; +} + +static int setup_udp_socket(meshlink_handle_t *mesh, const struct addrinfo *aip) { + int nfd = socket(aip->ai_family, SOCK_DGRAM, IPPROTO_UDP); + + if(nfd == -1) { + return -1; + } + +#ifdef FD_CLOEXEC + fcntl(nfd, F_SETFD, FD_CLOEXEC); +#endif + +#ifdef O_NONBLOCK + int flags = fcntl(nfd, F_GETFL); + + if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0) { + closesocket(nfd); + logger(mesh, MESHLINK_ERROR, "System call `%s' failed: %s", "fcntl", strerror(errno)); + return -1; + } + +#elif defined(WIN32) + unsigned long arg = 1; + + if(ioctlsocket(nfd, FIONBIO, &arg) != 0) { + closesocket(nfd); + logger(mesh, MESHLINK_ERROR, "Call to `%s' failed: %s", "ioctlsocket", sockstrerror(sockerrno)); + return -1; + } + +#endif + + int option = 1; + setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, (void *)&option, sizeof(option)); + setsockopt(nfd, SOL_SOCKET, SO_BROADCAST, (void *)&option, sizeof(option)); + +#if defined(IPV6_V6ONLY) + + if(aip->ai_family == AF_INET6) { + setsockopt(nfd, IPPROTO_IPV6, IPV6_V6ONLY, (void *)&option, sizeof(option)); + } + +#endif + +#if defined(IP_DONTFRAG) && !defined(IP_DONTFRAGMENT) +#define IP_DONTFRAGMENT IP_DONTFRAG +#endif + +#if defined(IP_MTU_DISCOVER) && defined(IP_PMTUDISC_DO) + option = IP_PMTUDISC_DO; + setsockopt(nfd, IPPROTO_IP, IP_MTU_DISCOVER, (void *)&option, sizeof(option)); +#elif defined(IP_DONTFRAGMENT) + option = 1; + setsockopt(nfd, IPPROTO_IP, IP_DONTFRAGMENT, (void *)&option, sizeof(option)); +#endif + + if(aip->ai_family == AF_INET6) { +#if defined(IPV6_MTU_DISCOVER) && defined(IPV6_PMTUDISC_DO) + option = IPV6_PMTUDISC_DO; + setsockopt(nfd, IPPROTO_IPV6, IPV6_MTU_DISCOVER, (void *)&option, sizeof(option)); +#elif defined(IPV6_DONTFRAG) + option = 1; + setsockopt(nfd, IPPROTO_IPV6, IPV6_DONTFRAG, (void *)&option, sizeof(option)); +#endif + } + + if(bind(nfd, aip->ai_addr, aip->ai_addrlen)) { + closesocket(nfd); + return -1; + } + + return nfd; +} + /* Add listening sockets. */ @@ -345,15 +456,9 @@ static bool add_listen_sockets(meshlink_handle_t *mesh) { /* Try to bind to TCP */ - int tcp_fd = socket(aip->ai_family, SOCK_STREAM, IPPROTO_TCP); + int tcp_fd = setup_tcp_listen_socket(mesh, aip); if(tcp_fd == -1) { - continue; - } - - if(bind(tcp_fd, aip->ai_addr, aip->ai_addrlen)) { - closesocket(tcp_fd); - if(errno == EADDRINUSE) { /* If this port is in use for any address family, avoid it. */ success = false; @@ -363,15 +468,9 @@ static bool add_listen_sockets(meshlink_handle_t *mesh) { } } - if(!setup_listen_socket(mesh, tcp_fd, aip->ai_family)) { - closesocket(tcp_fd); - success = false; - break; - } - /* If TCP worked, then we require that UDP works as well. */ - int udp_fd = socket(aip->ai_family, SOCK_DGRAM, IPPROTO_UDP); + int udp_fd = setup_udp_socket(mesh, aip); if(udp_fd == -1) { closesocket(tcp_fd); @@ -379,13 +478,6 @@ static bool add_listen_sockets(meshlink_handle_t *mesh) { break; } - if(bind(udp_fd, aip->ai_addr, aip->ai_addrlen) || !setup_vpn_in_socket(mesh, udp_fd, aip->ai_family)) { - closesocket(tcp_fd); - closesocket(udp_fd); - success = false; - break; - } - io_add(&mesh->loop, &mesh->listen_socket[mesh->listen_sockets].tcp, handle_new_meta_connection, &mesh->listen_socket[mesh->listen_sockets], tcp_fd, IO_READ); io_add(&mesh->loop, &mesh->listen_socket[mesh->listen_sockets].udp, handle_incoming_vpn_data, &mesh->listen_socket[mesh->listen_sockets], udp_fd, IO_READ); diff --git a/src/net_socket.c b/src/net_socket.c index 931f21d1..fcadd90c 100644 --- a/src/net_socket.c +++ b/src/net_socket.c @@ -72,95 +72,6 @@ static void configure_tcp(connection_t *c) { #endif } -bool setup_listen_socket(meshlink_handle_t *mesh, int nfd, int sa_family) { -#ifdef FD_CLOEXEC - fcntl(nfd, F_SETFD, FD_CLOEXEC); -#endif - - int option = 1; - setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, (void *)&option, sizeof(option)); - -#if defined(IPV6_V6ONLY) - - if(sa_family == AF_INET6) { - setsockopt(nfd, IPPROTO_IPV6, IPV6_V6ONLY, (void *)&option, sizeof(option)); - } - -#else -#warning IPV6_V6ONLY not defined -#endif - - if(listen(nfd, 3)) { - logger(mesh, MESHLINK_ERROR, "System call `%s' failed: %s", "listen", sockstrerror(sockerrno)); - return false; - } - - return true; -} - -bool setup_vpn_in_socket(meshlink_handle_t *mesh, int nfd, int sa_family) { -#ifdef FD_CLOEXEC - fcntl(nfd, F_SETFD, FD_CLOEXEC); -#endif - -#ifdef O_NONBLOCK - { - int flags = fcntl(nfd, F_GETFL); - - if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0) { - closesocket(nfd); - logger(mesh, MESHLINK_ERROR, "System call `%s' failed: %s", "fcntl", - strerror(errno)); - return false; - } - } -#elif defined(WIN32) - { - unsigned long arg = 1; - - if(ioctlsocket(nfd, FIONBIO, &arg) != 0) { - closesocket(nfd); - logger(mesh, MESHLINK_ERROR, "Call to `%s' failed: %s", "ioctlsocket", sockstrerror(sockerrno)); - return false; - } - } -#endif - - int option = 1; - setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, (void *)&option, sizeof(option)); - setsockopt(nfd, SOL_SOCKET, SO_BROADCAST, (void *)&option, sizeof(option)); - -#if defined(IPV6_V6ONLY) - - if(sa_family == AF_INET6) { - setsockopt(nfd, IPPROTO_IPV6, IPV6_V6ONLY, (void *)&option, sizeof(option)); - } - -#endif - -#if defined(IP_DONTFRAG) && !defined(IP_DONTFRAGMENT) -#define IP_DONTFRAGMENT IP_DONTFRAG -#endif - -#if defined(IP_MTU_DISCOVER) && defined(IP_PMTUDISC_DO) - option = IP_PMTUDISC_DO; - setsockopt(nfd, IPPROTO_IP, IP_MTU_DISCOVER, (void *)&option, sizeof(option)); -#elif defined(IP_DONTFRAGMENT) - option = 1; - setsockopt(nfd, IPPROTO_IP, IP_DONTFRAGMENT, (void *)&option, sizeof(option)); -#endif - -#if defined(IPV6_MTU_DISCOVER) && defined(IPV6_PMTUDISC_DO) - option = IPV6_PMTUDISC_DO; - setsockopt(nfd, IPPROTO_IPV6, IPV6_MTU_DISCOVER, (void *)&option, sizeof(option)); -#elif defined(IPV6_DONTFRAG) - option = 1; - setsockopt(nfd, IPPROTO_IPV6, IPV6_DONTFRAG, (void *)&option, sizeof(option)); -#endif - - return true; -} /* int setup_vpn_in_socket */ - static void retry_outgoing_handler(event_loop_t *loop, void *data) { assert(data); -- 2.39.2