1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2009-2010 The FreeBSD Foundation 5 * All rights reserved. 6 * 7 * This software was developed by Pawel Jakub Dawidek under sponsorship from 8 * the FreeBSD Foundation. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/types.h> 33 #include <sys/socket.h> 34 35 #include <errno.h> 36 #include <stdbool.h> 37 #include <stdint.h> 38 #include <stdio.h> 39 #include <string.h> 40 #include <unistd.h> 41 42 #include "pjdlog.h" 43 #include "proto_impl.h" 44 45 #define SP_CTX_MAGIC 0x50c3741 46 struct sp_ctx { 47 int sp_magic; 48 int sp_fd[2]; 49 int sp_side; 50 #define SP_SIDE_UNDEF 0 51 #define SP_SIDE_CLIENT 1 52 #define SP_SIDE_SERVER 2 53 }; 54 55 static void sp_close(void *ctx); 56 57 static int 58 sp_client(const char *srcaddr, const char *dstaddr, void **ctxp) 59 { 60 struct sp_ctx *spctx; 61 int ret; 62 63 if (strcmp(dstaddr, "socketpair://") != 0) 64 return (-1); 65 66 PJDLOG_ASSERT(srcaddr == NULL); 67 68 spctx = malloc(sizeof(*spctx)); 69 if (spctx == NULL) 70 return (errno); 71 72 if (socketpair(PF_UNIX, SOCK_STREAM, 0, spctx->sp_fd) == -1) { 73 ret = errno; 74 free(spctx); 75 return (ret); 76 } 77 78 spctx->sp_side = SP_SIDE_UNDEF; 79 spctx->sp_magic = SP_CTX_MAGIC; 80 *ctxp = spctx; 81 82 return (0); 83 } 84 85 static int 86 sp_send(void *ctx, const unsigned char *data, size_t size, int fd) 87 { 88 struct sp_ctx *spctx = ctx; 89 int sock; 90 91 PJDLOG_ASSERT(spctx != NULL); 92 PJDLOG_ASSERT(spctx->sp_magic == SP_CTX_MAGIC); 93 94 switch (spctx->sp_side) { 95 case SP_SIDE_UNDEF: 96 /* 97 * If the first operation done by the caller is proto_send(), 98 * we assume this is the client. 99 */ 100 /* FALLTHROUGH */ 101 spctx->sp_side = SP_SIDE_CLIENT; 102 /* Close other end. */ 103 close(spctx->sp_fd[1]); 104 spctx->sp_fd[1] = -1; 105 case SP_SIDE_CLIENT: 106 PJDLOG_ASSERT(spctx->sp_fd[0] >= 0); 107 sock = spctx->sp_fd[0]; 108 break; 109 case SP_SIDE_SERVER: 110 PJDLOG_ASSERT(spctx->sp_fd[1] >= 0); 111 sock = spctx->sp_fd[1]; 112 break; 113 default: 114 PJDLOG_ABORT("Invalid socket side (%d).", spctx->sp_side); 115 } 116 117 /* Someone is just trying to decide about side. */ 118 if (data == NULL) 119 return (0); 120 121 return (proto_common_send(sock, data, size, fd)); 122 } 123 124 static int 125 sp_recv(void *ctx, unsigned char *data, size_t size, int *fdp) 126 { 127 struct sp_ctx *spctx = ctx; 128 int fd; 129 130 PJDLOG_ASSERT(spctx != NULL); 131 PJDLOG_ASSERT(spctx->sp_magic == SP_CTX_MAGIC); 132 133 switch (spctx->sp_side) { 134 case SP_SIDE_UNDEF: 135 /* 136 * If the first operation done by the caller is proto_recv(), 137 * we assume this is the server. 138 */ 139 /* FALLTHROUGH */ 140 spctx->sp_side = SP_SIDE_SERVER; 141 /* Close other end. */ 142 close(spctx->sp_fd[0]); 143 spctx->sp_fd[0] = -1; 144 case SP_SIDE_SERVER: 145 PJDLOG_ASSERT(spctx->sp_fd[1] >= 0); 146 fd = spctx->sp_fd[1]; 147 break; 148 case SP_SIDE_CLIENT: 149 PJDLOG_ASSERT(spctx->sp_fd[0] >= 0); 150 fd = spctx->sp_fd[0]; 151 break; 152 default: 153 PJDLOG_ABORT("Invalid socket side (%d).", spctx->sp_side); 154 } 155 156 /* Someone is just trying to decide about side. */ 157 if (data == NULL) 158 return (0); 159 160 return (proto_common_recv(fd, data, size, fdp)); 161 } 162 163 static int 164 sp_descriptor(const void *ctx) 165 { 166 const struct sp_ctx *spctx = ctx; 167 168 PJDLOG_ASSERT(spctx != NULL); 169 PJDLOG_ASSERT(spctx->sp_magic == SP_CTX_MAGIC); 170 PJDLOG_ASSERT(spctx->sp_side == SP_SIDE_CLIENT || 171 spctx->sp_side == SP_SIDE_SERVER); 172 173 switch (spctx->sp_side) { 174 case SP_SIDE_CLIENT: 175 PJDLOG_ASSERT(spctx->sp_fd[0] >= 0); 176 return (spctx->sp_fd[0]); 177 case SP_SIDE_SERVER: 178 PJDLOG_ASSERT(spctx->sp_fd[1] >= 0); 179 return (spctx->sp_fd[1]); 180 } 181 182 PJDLOG_ABORT("Invalid socket side (%d).", spctx->sp_side); 183 } 184 185 static void 186 sp_close(void *ctx) 187 { 188 struct sp_ctx *spctx = ctx; 189 190 PJDLOG_ASSERT(spctx != NULL); 191 PJDLOG_ASSERT(spctx->sp_magic == SP_CTX_MAGIC); 192 193 switch (spctx->sp_side) { 194 case SP_SIDE_UNDEF: 195 PJDLOG_ASSERT(spctx->sp_fd[0] >= 0); 196 close(spctx->sp_fd[0]); 197 spctx->sp_fd[0] = -1; 198 PJDLOG_ASSERT(spctx->sp_fd[1] >= 0); 199 close(spctx->sp_fd[1]); 200 spctx->sp_fd[1] = -1; 201 break; 202 case SP_SIDE_CLIENT: 203 PJDLOG_ASSERT(spctx->sp_fd[0] >= 0); 204 close(spctx->sp_fd[0]); 205 spctx->sp_fd[0] = -1; 206 PJDLOG_ASSERT(spctx->sp_fd[1] == -1); 207 break; 208 case SP_SIDE_SERVER: 209 PJDLOG_ASSERT(spctx->sp_fd[1] >= 0); 210 close(spctx->sp_fd[1]); 211 spctx->sp_fd[1] = -1; 212 PJDLOG_ASSERT(spctx->sp_fd[0] == -1); 213 break; 214 default: 215 PJDLOG_ABORT("Invalid socket side (%d).", spctx->sp_side); 216 } 217 218 spctx->sp_magic = 0; 219 free(spctx); 220 } 221 222 static struct proto sp_proto = { 223 .prt_name = "socketpair", 224 .prt_client = sp_client, 225 .prt_send = sp_send, 226 .prt_recv = sp_recv, 227 .prt_descriptor = sp_descriptor, 228 .prt_close = sp_close 229 }; 230 231 static __constructor void 232 sp_ctor(void) 233 { 234 235 proto_register(&sp_proto, false); 236 } 237