Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 1 | /* |
| 2 | * |
| 3 | * Copyright 2014, Google Inc. |
| 4 | * All rights reserved. |
| 5 | * |
| 6 | * Redistribution and use in source and binary forms, with or without |
| 7 | * modification, are permitted provided that the following conditions are |
| 8 | * met: |
| 9 | * |
| 10 | * * Redistributions of source code must retain the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer. |
| 12 | * * Redistributions in binary form must reproduce the above |
| 13 | * copyright notice, this list of conditions and the following disclaimer |
| 14 | * in the documentation and/or other materials provided with the |
| 15 | * distribution. |
| 16 | * * Neither the name of Google Inc. nor the names of its |
| 17 | * contributors may be used to endorse or promote products derived from |
| 18 | * this software without specific prior written permission. |
| 19 | * |
| 20 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 21 | * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 22 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| 23 | * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| 24 | * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| 25 | * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| 26 | * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 27 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 28 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 29 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| 30 | * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 31 | * |
| 32 | */ |
| 33 | |
| 34 | #include "src/core/endpoint/socket_utils.h" |
| 35 | |
nnoble | 0c475f0 | 2014-12-05 15:37:39 -0800 | [diff] [blame^] | 36 | #include <arpa/inet.h> |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 37 | #include <limits.h> |
| 38 | #include <fcntl.h> |
| 39 | #include <netinet/in.h> |
| 40 | #include <netinet/tcp.h> |
| 41 | #include <stdio.h> |
| 42 | #include <sys/types.h> |
| 43 | #include <sys/socket.h> |
| 44 | #include <unistd.h> |
| 45 | #include <string.h> |
| 46 | #include <errno.h> |
| 47 | |
nnoble | 0c475f0 | 2014-12-05 15:37:39 -0800 | [diff] [blame^] | 48 | #include <grpc/support/host_port.h> |
| 49 | #include <grpc/support/string.h> |
| 50 | #include <grpc/support/log.h> |
| 51 | #include <grpc/support/port_platform.h> |
| 52 | |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 53 | /* set a socket to non blocking mode */ |
| 54 | int grpc_set_socket_nonblocking(int fd, int non_blocking) { |
| 55 | int oldflags = fcntl(fd, F_GETFL, 0); |
| 56 | if (oldflags < 0) { |
| 57 | return 0; |
| 58 | } |
| 59 | |
| 60 | if (non_blocking) { |
| 61 | oldflags |= O_NONBLOCK; |
| 62 | } else { |
| 63 | oldflags &= ~O_NONBLOCK; |
| 64 | } |
| 65 | |
| 66 | if (fcntl(fd, F_SETFL, oldflags) != 0) { |
| 67 | return 0; |
| 68 | } |
| 69 | |
| 70 | return 1; |
| 71 | } |
| 72 | |
| 73 | /* set a socket to close on exec */ |
| 74 | int grpc_set_socket_cloexec(int fd, int close_on_exec) { |
| 75 | int oldflags = fcntl(fd, F_GETFD, 0); |
| 76 | if (oldflags < 0) { |
| 77 | return 0; |
| 78 | } |
| 79 | |
| 80 | if (close_on_exec) { |
| 81 | oldflags |= FD_CLOEXEC; |
| 82 | } else { |
| 83 | oldflags &= ~FD_CLOEXEC; |
| 84 | } |
| 85 | |
| 86 | if (fcntl(fd, F_SETFD, oldflags) != 0) { |
| 87 | return 0; |
| 88 | } |
| 89 | |
| 90 | return 1; |
| 91 | } |
| 92 | |
| 93 | /* set a socket to reuse old addresses */ |
| 94 | int grpc_set_socket_reuse_addr(int fd, int reuse) { |
| 95 | int val = (reuse != 0); |
| 96 | int newval; |
| 97 | socklen_t intlen = sizeof(newval); |
| 98 | return 0 == setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val)) && |
| 99 | 0 == getsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &newval, &intlen) && |
| 100 | newval == val; |
| 101 | } |
| 102 | |
| 103 | /* disable nagle */ |
| 104 | int grpc_set_socket_low_latency(int fd, int low_latency) { |
| 105 | int val = (low_latency != 0); |
| 106 | int newval; |
| 107 | socklen_t intlen = sizeof(newval); |
| 108 | return 0 == setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &val, sizeof(val)) && |
| 109 | 0 == getsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &newval, &intlen) && |
| 110 | newval == val; |
| 111 | } |
nnoble | 0c475f0 | 2014-12-05 15:37:39 -0800 | [diff] [blame^] | 112 | |
| 113 | /* This should be 0 in production, but it may be enabled for testing or |
| 114 | debugging purposes, to simulate an environment where IPv6 sockets can't |
| 115 | also speak IPv4. */ |
| 116 | int grpc_forbid_dualstack_sockets_for_testing = 0; |
| 117 | |
| 118 | static int set_socket_dualstack(int fd) { |
| 119 | if (!grpc_forbid_dualstack_sockets_for_testing) { |
| 120 | const int off = 0; |
| 121 | return 0 == setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &off, sizeof(off)); |
| 122 | } else { |
| 123 | /* Force an IPv6-only socket, for testing purposes. */ |
| 124 | const int on = 1; |
| 125 | setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)); |
| 126 | return 0; |
| 127 | } |
| 128 | } |
| 129 | |
| 130 | int grpc_create_dualstack_socket(const struct sockaddr *addr, int type, |
| 131 | int protocol, grpc_dualstack_mode *dsmode) { |
| 132 | int family = addr->sa_family; |
| 133 | if (family == AF_INET6) { |
| 134 | int fd = socket(family, type, protocol); |
| 135 | /* Check if we've got a valid dualstack socket. */ |
| 136 | if (fd >= 0 && set_socket_dualstack(fd)) { |
| 137 | *dsmode = GRPC_DSMODE_DUALSTACK; |
| 138 | return fd; |
| 139 | } |
| 140 | /* If this isn't an IPv4 address, then return whatever we've got. */ |
| 141 | if (!grpc_sockaddr_is_v4mapped(addr, NULL)) { |
| 142 | *dsmode = GRPC_DSMODE_IPV6; |
| 143 | return fd; |
| 144 | } |
| 145 | /* Fall back to AF_INET. */ |
| 146 | if (fd >= 0) { |
| 147 | close(fd); |
| 148 | } |
| 149 | family = AF_INET; |
| 150 | } |
| 151 | *dsmode = family == AF_INET ? GRPC_DSMODE_IPV4 : GRPC_DSMODE_NONE; |
| 152 | return socket(family, type, protocol); |
| 153 | } |
| 154 | |
| 155 | static const gpr_uint8 kV4MappedPrefix[] = {0, 0, 0, 0, 0, 0, |
| 156 | 0, 0, 0, 0, 0xff, 0xff}; |
| 157 | |
| 158 | int grpc_sockaddr_is_v4mapped(const struct sockaddr *addr, |
| 159 | struct sockaddr_in *addr4_out) { |
| 160 | GPR_ASSERT(addr != (struct sockaddr *)addr4_out); |
| 161 | if (addr->sa_family == AF_INET6) { |
| 162 | const struct sockaddr_in6 *addr6 = (const struct sockaddr_in6 *)addr; |
| 163 | if (memcmp(addr6->sin6_addr.s6_addr, kV4MappedPrefix, |
| 164 | sizeof(kV4MappedPrefix)) == 0) { |
| 165 | if (addr4_out != NULL) { |
| 166 | /* Normalize ::ffff:0.0.0.0/96 to IPv4. */ |
| 167 | memset(addr4_out, 0, sizeof(*addr4_out)); |
| 168 | addr4_out->sin_family = AF_INET; |
| 169 | /* s6_addr32 would be nice, but it's non-standard. */ |
| 170 | memcpy(&addr4_out->sin_addr, &addr6->sin6_addr.s6_addr[12], 4); |
| 171 | addr4_out->sin_port = addr6->sin6_port; |
| 172 | } |
| 173 | return 1; |
| 174 | } |
| 175 | } |
| 176 | return 0; |
| 177 | } |
| 178 | |
| 179 | int grpc_sockaddr_to_v4mapped(const struct sockaddr *addr, |
| 180 | struct sockaddr_in6 *addr6_out) { |
| 181 | GPR_ASSERT(addr != (struct sockaddr *)addr6_out); |
| 182 | if (addr->sa_family == AF_INET) { |
| 183 | const struct sockaddr_in *addr4 = (const struct sockaddr_in *)addr; |
| 184 | memset(addr6_out, 0, sizeof(*addr6_out)); |
| 185 | addr6_out->sin6_family = AF_INET6; |
| 186 | memcpy(&addr6_out->sin6_addr.s6_addr[0], kV4MappedPrefix, 12); |
| 187 | memcpy(&addr6_out->sin6_addr.s6_addr[12], &addr4->sin_addr, 4); |
| 188 | addr6_out->sin6_port = addr4->sin_port; |
| 189 | return 1; |
| 190 | } |
| 191 | return 0; |
| 192 | } |
| 193 | |
| 194 | int grpc_sockaddr_is_wildcard(const struct sockaddr *addr, int *port_out) { |
| 195 | struct sockaddr_in addr4_normalized; |
| 196 | if (grpc_sockaddr_is_v4mapped(addr, &addr4_normalized)) { |
| 197 | addr = (struct sockaddr *)&addr4_normalized; |
| 198 | } |
| 199 | if (addr->sa_family == AF_INET) { |
| 200 | /* Check for 0.0.0.0 */ |
| 201 | const struct sockaddr_in *addr4 = (const struct sockaddr_in *)addr; |
| 202 | if (addr4->sin_addr.s_addr != 0) { |
| 203 | return 0; |
| 204 | } |
| 205 | *port_out = ntohs(addr4->sin_port); |
| 206 | return 1; |
| 207 | } else if (addr->sa_family == AF_INET6) { |
| 208 | /* Check for :: */ |
| 209 | const struct sockaddr_in6 *addr6 = (const struct sockaddr_in6 *)addr; |
| 210 | int i; |
| 211 | for (i = 0; i < 16; i++) { |
| 212 | if (addr6->sin6_addr.s6_addr[i] != 0) { |
| 213 | return 0; |
| 214 | } |
| 215 | } |
| 216 | *port_out = ntohs(addr6->sin6_port); |
| 217 | return 1; |
| 218 | } else { |
| 219 | return 0; |
| 220 | } |
| 221 | } |
| 222 | |
| 223 | void grpc_sockaddr_make_wildcards(int port, struct sockaddr_in *wild4_out, |
| 224 | struct sockaddr_in6 *wild6_out) { |
| 225 | memset(wild4_out, 0, sizeof(*wild4_out)); |
| 226 | wild4_out->sin_family = AF_INET; |
| 227 | wild4_out->sin_port = htons(port); |
| 228 | |
| 229 | memset(wild6_out, 0, sizeof(*wild6_out)); |
| 230 | wild6_out->sin6_family = AF_INET6; |
| 231 | wild6_out->sin6_port = htons(port); |
| 232 | } |
| 233 | |
| 234 | int grpc_sockaddr_to_string(char **out, const struct sockaddr *addr, |
| 235 | int normalize) { |
| 236 | const int save_errno = errno; |
| 237 | struct sockaddr_in addr_normalized; |
| 238 | char ntop_buf[INET6_ADDRSTRLEN]; |
| 239 | const void *ip = NULL; |
| 240 | int port; |
| 241 | int ret; |
| 242 | |
| 243 | *out = NULL; |
| 244 | if (normalize && grpc_sockaddr_is_v4mapped(addr, &addr_normalized)) { |
| 245 | addr = (const struct sockaddr *)&addr_normalized; |
| 246 | } |
| 247 | if (addr->sa_family == AF_INET) { |
| 248 | const struct sockaddr_in *addr4 = (const struct sockaddr_in *)addr; |
| 249 | ip = &addr4->sin_addr; |
| 250 | port = ntohs(addr4->sin_port); |
| 251 | } else if (addr->sa_family == AF_INET6) { |
| 252 | const struct sockaddr_in6 *addr6 = (const struct sockaddr_in6 *)addr; |
| 253 | ip = &addr6->sin6_addr; |
| 254 | port = ntohs(addr6->sin6_port); |
| 255 | } |
| 256 | if (ip != NULL && |
| 257 | inet_ntop(addr->sa_family, ip, ntop_buf, sizeof(ntop_buf)) != NULL) { |
| 258 | ret = gpr_join_host_port(out, ntop_buf, port); |
| 259 | } else { |
| 260 | ret = gpr_asprintf(out, "(sockaddr family=%d)", addr->sa_family); |
| 261 | } |
| 262 | /* This is probably redundant, but we wouldn't want to log the wrong error. */ |
| 263 | errno = save_errno; |
| 264 | return ret; |
| 265 | } |