1 /* 2 * 3 * Copyright 2015 gRPC authors. 4 * 5 * Licensed under the Apache License, Version 2.0 (the "License"); 6 * you may not use this file except in compliance with the License. 7 * You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 * 17 */ 18 19 #ifndef GRPC_CORE_LIB_IOMGR_SOCKET_UTILS_POSIX_H 20 #define GRPC_CORE_LIB_IOMGR_SOCKET_UTILS_POSIX_H 21 22 #include <grpc/support/port_platform.h> 23 24 #include "src/core/lib/iomgr/resolve_address.h" 25 26 #include <sys/socket.h> 27 #include <unistd.h> 28 29 #include <grpc/impl/codegen/grpc_types.h> 30 #include "src/core/lib/iomgr/error.h" 31 #include "src/core/lib/iomgr/socket_factory_posix.h" 32 #include "src/core/lib/iomgr/socket_mutator.h" 33 34 /* a wrapper for accept or accept4 */ 35 int grpc_accept4(int sockfd, grpc_resolved_address* resolved_addr, int nonblock, 36 int cloexec); 37 38 /* set a socket to non blocking mode */ 39 grpc_error* grpc_set_socket_nonblocking(int fd, int non_blocking); 40 41 /* set a socket to close on exec */ 42 grpc_error* grpc_set_socket_cloexec(int fd, int close_on_exec); 43 44 /* set a socket to reuse old addresses */ 45 grpc_error* grpc_set_socket_reuse_addr(int fd, int reuse); 46 47 /* return true if SO_REUSEPORT is supported */ 48 bool grpc_is_socket_reuse_port_supported(); 49 50 /* disable nagle */ 51 grpc_error* grpc_set_socket_low_latency(int fd, int low_latency); 52 53 /* set SO_REUSEPORT */ 54 grpc_error* grpc_set_socket_reuse_port(int fd, int reuse); 55 56 /* Configure the default values for TCP_USER_TIMEOUT */ 57 void config_default_tcp_user_timeout(bool enable, int timeout, bool is_client); 58 59 /* Set TCP_USER_TIMEOUT */ 60 grpc_error* grpc_set_socket_tcp_user_timeout( 61 int fd, const grpc_channel_args* channel_args, bool is_client); 62 63 /* Returns true if this system can create AF_INET6 sockets bound to ::1. 64 The value is probed once, and cached for the life of the process. 65 66 This is more restrictive than checking for socket(AF_INET6) to succeed, 67 because Linux with "net.ipv6.conf.all.disable_ipv6 = 1" is able to create 68 and bind IPv6 sockets, but cannot connect to a getsockname() of [::]:port 69 without a valid loopback interface. Rather than expose this half-broken 70 state to library users, we turn off IPv6 sockets. */ 71 int grpc_ipv6_loopback_available(void); 72 73 /* Tries to set SO_NOSIGPIPE if available on this platform. 74 If SO_NO_SIGPIPE is not available, returns 1. */ 75 grpc_error* grpc_set_socket_no_sigpipe_if_possible(int fd); 76 77 /* Tries to set IP_PKTINFO if available on this platform. 78 If IP_PKTINFO is not available, returns 1. */ 79 grpc_error* grpc_set_socket_ip_pktinfo_if_possible(int fd); 80 81 /* Tries to set IPV6_RECVPKTINFO if available on this platform. 82 If IPV6_RECVPKTINFO is not available, returns 1. */ 83 grpc_error* grpc_set_socket_ipv6_recvpktinfo_if_possible(int fd); 84 85 /* Tries to set the socket's send buffer to given size. */ 86 grpc_error* grpc_set_socket_sndbuf(int fd, int buffer_size_bytes); 87 88 /* Tries to set the socket's receive buffer to given size. */ 89 grpc_error* grpc_set_socket_rcvbuf(int fd, int buffer_size_bytes); 90 91 /* Tries to set the socket using a grpc_socket_mutator */ 92 grpc_error* grpc_set_socket_with_mutator(int fd, grpc_socket_mutator* mutator); 93 94 /* An enum to keep track of IPv4/IPv6 socket modes. 95 96 Currently, this information is only used when a socket is first created, but 97 in the future we may wish to store it alongside the fd. This would let calls 98 like sendto() know which family to use without asking the kernel first. */ 99 typedef enum grpc_dualstack_mode { 100 /* Uninitialized, or a non-IP socket. */ 101 GRPC_DSMODE_NONE, 102 /* AF_INET only. */ 103 GRPC_DSMODE_IPV4, 104 /* AF_INET6 only, because IPV6_V6ONLY could not be cleared. */ 105 GRPC_DSMODE_IPV6, 106 /* AF_INET6, which also supports ::ffff-mapped IPv4 addresses. */ 107 GRPC_DSMODE_DUALSTACK 108 } grpc_dualstack_mode; 109 110 /* Only tests should use this flag. */ 111 extern int grpc_forbid_dualstack_sockets_for_testing; 112 113 /* Creates a new socket for connecting to (or listening on) an address. 114 115 If addr is AF_INET6, this creates an IPv6 socket first. If that fails, 116 and addr is within ::ffff:0.0.0.0/96, then it automatically falls back to 117 an IPv4 socket. 118 119 If addr is AF_INET, AF_UNIX, or anything else, then this is similar to 120 calling socket() directly. 121 122 Returns an fd on success, otherwise returns -1 with errno set to the result 123 of a failed socket() call. 124 125 The *dsmode output indicates which address family was actually created. 126 The recommended way to use this is: 127 - First convert to IPv6 using grpc_sockaddr_to_v4mapped(). 128 - Create the socket. 129 - If *dsmode is IPV4, use grpc_sockaddr_is_v4mapped() to convert back to 130 IPv4, so that bind() or connect() see the correct family. 131 Also, it's important to distinguish between DUALSTACK and IPV6 when 132 listening on the [::] wildcard address. */ 133 grpc_error* grpc_create_dualstack_socket(const grpc_resolved_address* addr, 134 int type, int protocol, 135 grpc_dualstack_mode* dsmode, 136 int* newfd); 137 138 /* Same as grpc_create_dualstack_socket(), but use the given socket factory (if 139 non-null) to create the socket, rather than calling socket() directly. */ 140 grpc_error* grpc_create_dualstack_socket_using_factory( 141 grpc_socket_factory* factory, const grpc_resolved_address* addr, int type, 142 int protocol, grpc_dualstack_mode* dsmode, int* newfd); 143 144 #endif /* GRPC_CORE_LIB_IOMGR_SOCKET_UTILS_POSIX_H */ 145