| /* |
| * |
| * Copyright 2015, Google Inc. |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are |
| * met: |
| * |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above |
| * copyright notice, this list of conditions and the following disclaimer |
| * in the documentation and/or other materials provided with the |
| * distribution. |
| * * Neither the name of Google Inc. nor the names of its |
| * contributors may be used to endorse or promote products derived from |
| * this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| * |
| */ |
| |
| #include <grpc/support/port_platform.h> |
| |
| #ifdef GPR_POSIX_SOCKET |
| |
| #include "src/core/iomgr/socket_utils_posix.h" |
| |
| #include <arpa/inet.h> |
| #include <limits.h> |
| #include <fcntl.h> |
| #include <netinet/in.h> |
| #include <netinet/tcp.h> |
| #include <stdio.h> |
| #include <sys/types.h> |
| #include <sys/socket.h> |
| #include <unistd.h> |
| #include <string.h> |
| #include <errno.h> |
| |
| #include "src/core/iomgr/sockaddr_utils.h" |
| #include "src/core/support/string.h" |
| #include <grpc/support/host_port.h> |
| #include <grpc/support/log.h> |
| #include <grpc/support/port_platform.h> |
| #include <grpc/support/sync.h> |
| |
| /* set a socket to non blocking mode */ |
| int grpc_set_socket_nonblocking(int fd, int non_blocking) { |
| int oldflags = fcntl(fd, F_GETFL, 0); |
| if (oldflags < 0) { |
| return 0; |
| } |
| |
| if (non_blocking) { |
| oldflags |= O_NONBLOCK; |
| } else { |
| oldflags &= ~O_NONBLOCK; |
| } |
| |
| if (fcntl(fd, F_SETFL, oldflags) != 0) { |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| int grpc_set_socket_no_sigpipe_if_possible(int fd) { |
| #ifdef GPR_HAVE_SO_NOSIGPIPE |
| int val = 1; |
| int newval; |
| socklen_t intlen = sizeof(newval); |
| return 0 == setsockopt(fd, SOL_SOCKET, SO_NOSIGPIPE, &val, sizeof(val)) && |
| 0 == getsockopt(fd, SOL_SOCKET, SO_NOSIGPIPE, &newval, &intlen) && |
| (newval != 0) == val; |
| #else |
| return 1; |
| #endif |
| } |
| |
| /* set a socket to close on exec */ |
| int grpc_set_socket_cloexec(int fd, int close_on_exec) { |
| int oldflags = fcntl(fd, F_GETFD, 0); |
| if (oldflags < 0) { |
| return 0; |
| } |
| |
| if (close_on_exec) { |
| oldflags |= FD_CLOEXEC; |
| } else { |
| oldflags &= ~FD_CLOEXEC; |
| } |
| |
| if (fcntl(fd, F_SETFD, oldflags) != 0) { |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| /* set a socket to reuse old addresses */ |
| int grpc_set_socket_reuse_addr(int fd, int reuse) { |
| int val = (reuse != 0); |
| int newval; |
| socklen_t intlen = sizeof(newval); |
| return 0 == setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val)) && |
| 0 == getsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &newval, &intlen) && |
| (newval != 0) == val; |
| } |
| |
| /* disable nagle */ |
| int grpc_set_socket_low_latency(int fd, int low_latency) { |
| int val = (low_latency != 0); |
| int newval; |
| socklen_t intlen = sizeof(newval); |
| return 0 == setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &val, sizeof(val)) && |
| 0 == getsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &newval, &intlen) && |
| (newval != 0) == val; |
| } |
| |
| static gpr_once g_probe_ipv6_once = GPR_ONCE_INIT; |
| static int g_ipv6_loopback_available; |
| |
| static void probe_ipv6_once(void) { |
| int fd = socket(AF_INET6, SOCK_STREAM, 0); |
| g_ipv6_loopback_available = 0; |
| if (fd < 0) { |
| gpr_log(GPR_INFO, "Disabling AF_INET6 sockets because socket() failed."); |
| } else { |
| struct sockaddr_in6 addr; |
| memset(&addr, 0, sizeof(addr)); |
| addr.sin6_family = AF_INET6; |
| addr.sin6_addr.s6_addr[15] = 1; /* [::1]:0 */ |
| if (bind(fd, (struct sockaddr *)&addr, sizeof(addr)) == 0) { |
| g_ipv6_loopback_available = 1; |
| } else { |
| gpr_log(GPR_INFO, |
| "Disabling AF_INET6 sockets because ::1 is not available."); |
| } |
| close(fd); |
| } |
| } |
| |
| int grpc_ipv6_loopback_available(void) { |
| gpr_once_init(&g_probe_ipv6_once, probe_ipv6_once); |
| return g_ipv6_loopback_available; |
| } |
| |
| /* This should be 0 in production, but it may be enabled for testing or |
| debugging purposes, to simulate an environment where IPv6 sockets can't |
| also speak IPv4. */ |
| int grpc_forbid_dualstack_sockets_for_testing = 0; |
| |
| static int set_socket_dualstack(int fd) { |
| if (!grpc_forbid_dualstack_sockets_for_testing) { |
| const int off = 0; |
| return 0 == setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &off, sizeof(off)); |
| } else { |
| /* Force an IPv6-only socket, for testing purposes. */ |
| const int on = 1; |
| setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)); |
| return 0; |
| } |
| } |
| |
| int grpc_create_dualstack_socket(const struct sockaddr *addr, int type, |
| int protocol, grpc_dualstack_mode *dsmode) { |
| int family = addr->sa_family; |
| if (family == AF_INET6) { |
| int fd; |
| if (grpc_ipv6_loopback_available()) { |
| fd = socket(family, type, protocol); |
| } else { |
| fd = -1; |
| errno = EAFNOSUPPORT; |
| } |
| /* Check if we've got a valid dualstack socket. */ |
| if (fd >= 0 && set_socket_dualstack(fd)) { |
| *dsmode = GRPC_DSMODE_DUALSTACK; |
| return fd; |
| } |
| /* If this isn't an IPv4 address, then return whatever we've got. */ |
| if (!grpc_sockaddr_is_v4mapped(addr, NULL)) { |
| *dsmode = GRPC_DSMODE_IPV6; |
| return fd; |
| } |
| /* Fall back to AF_INET. */ |
| if (fd >= 0) { |
| close(fd); |
| } |
| family = AF_INET; |
| } |
| *dsmode = family == AF_INET ? GRPC_DSMODE_IPV4 : GRPC_DSMODE_NONE; |
| return socket(family, type, protocol); |
| } |
| |
| #endif |