1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 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/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 #include <sys/types.h> 36 #include <sys/socket.h> 37 38 #include <errno.h> 39 #include <stdbool.h> 40 #include <stdint.h> 41 #include <stdio.h> 42 #include <string.h> 43 #include <unistd.h> 44 45 #include "pjdlog.h" 46 #include "proto_impl.h" 47 48 #define SP_CTX_MAGIC 0x50c3741 49 struct sp_ctx { 50 int sp_magic; 51 int sp_fd[2]; 52 int sp_side; 53 #define SP_SIDE_UNDEF 0 54 #define SP_SIDE_CLIENT 1 55 #define SP_SIDE_SERVER 2 56 }; 57 58 static void sp_close(void *ctx); 59 60 static int 61 sp_client(const char *srcaddr, const char *dstaddr, void **ctxp) 62 { 63 struct sp_ctx *spctx; 64 int ret; 65 66 if (strcmp(dstaddr, "socketpair://") != 0) 67 return (-1); 68 69 PJDLOG_ASSERT(srcaddr == NULL); 70 71 spctx = malloc(sizeof(*spctx)); 72 if (spctx == NULL) 73 return (errno); 74 75 if (socketpair(PF_UNIX, SOCK_STREAM, 0, spctx->sp_fd) == -1) { 76 ret = errno; 77 free(spctx); 78 return (ret); 79 } 80 81 spctx->sp_side = SP_SIDE_UNDEF; 82 spctx->sp_magic = SP_CTX_MAGIC; 83 *ctxp = spctx; 84 85 return (0); 86 } 87 88 static int 89 sp_send(void *ctx, const unsigned char *data, size_t size, int fd) 90 { 91 struct sp_ctx *spctx = ctx; 92 int sock; 93 94 PJDLOG_ASSERT(spctx != NULL); 95 PJDLOG_ASSERT(spctx->sp_magic == SP_CTX_MAGIC); 96 97 switch (spctx->sp_side) { 98 case SP_SIDE_UNDEF: 99 /* 100 * If the first operation done by the caller is proto_send(), 101 * we assume this is the client. 102 */ 103 /* FALLTHROUGH */ 104 spctx->sp_side = SP_SIDE_CLIENT; 105 /* Close other end. */ 106 close(spctx->sp_fd[1]); 107 spctx->sp_fd[1] = -1; 108 case SP_SIDE_CLIENT: 109 PJDLOG_ASSERT(spctx->sp_fd[0] >= 0); 110 sock = spctx->sp_fd[0]; 111 break; 112 case SP_SIDE_SERVER: 113 PJDLOG_ASSERT(spctx->sp_fd[1] >= 0); 114 sock = spctx->sp_fd[1]; 115 break; 116 default: 117 PJDLOG_ABORT("Invalid socket side (%d).", spctx->sp_side); 118 } 119 120 /* Someone is just trying to decide about side. */ 121 if (data == NULL) 122 return (0); 123 124 return (proto_common_send(sock, data, size, fd)); 125 } 126 127 static int 128 sp_recv(void *ctx, unsigned char *data, size_t size, int *fdp) 129 { 130 struct sp_ctx *spctx = ctx; 131 int fd; 132 133 PJDLOG_ASSERT(spctx != NULL); 134 PJDLOG_ASSERT(spctx->sp_magic == SP_CTX_MAGIC); 135 136 switch (spctx->sp_side) { 137 case SP_SIDE_UNDEF: 138 /* 139 * If the first operation done by the caller is proto_recv(), 140 * we assume this is the server. 141 */ 142 /* FALLTHROUGH */ 143 spctx->sp_side = SP_SIDE_SERVER; 144 /* Close other end. */ 145 close(spctx->sp_fd[0]); 146 spctx->sp_fd[0] = -1; 147 case SP_SIDE_SERVER: 148 PJDLOG_ASSERT(spctx->sp_fd[1] >= 0); 149 fd = spctx->sp_fd[1]; 150 break; 151 case SP_SIDE_CLIENT: 152 PJDLOG_ASSERT(spctx->sp_fd[0] >= 0); 153 fd = spctx->sp_fd[0]; 154 break; 155 default: 156 PJDLOG_ABORT("Invalid socket side (%d).", spctx->sp_side); 157 } 158 159 /* Someone is just trying to decide about side. */ 160 if (data == NULL) 161 return (0); 162 163 return (proto_common_recv(fd, data, size, fdp)); 164 } 165 166 static int 167 sp_descriptor(const void *ctx) 168 { 169 const struct sp_ctx *spctx = ctx; 170 171 PJDLOG_ASSERT(spctx != NULL); 172 PJDLOG_ASSERT(spctx->sp_magic == SP_CTX_MAGIC); 173 PJDLOG_ASSERT(spctx->sp_side == SP_SIDE_CLIENT || 174 spctx->sp_side == SP_SIDE_SERVER); 175 176 switch (spctx->sp_side) { 177 case SP_SIDE_CLIENT: 178 PJDLOG_ASSERT(spctx->sp_fd[0] >= 0); 179 return (spctx->sp_fd[0]); 180 case SP_SIDE_SERVER: 181 PJDLOG_ASSERT(spctx->sp_fd[1] >= 0); 182 return (spctx->sp_fd[1]); 183 } 184 185 PJDLOG_ABORT("Invalid socket side (%d).", spctx->sp_side); 186 } 187 188 static void 189 sp_close(void *ctx) 190 { 191 struct sp_ctx *spctx = ctx; 192 193 PJDLOG_ASSERT(spctx != NULL); 194 PJDLOG_ASSERT(spctx->sp_magic == SP_CTX_MAGIC); 195 196 switch (spctx->sp_side) { 197 case SP_SIDE_UNDEF: 198 PJDLOG_ASSERT(spctx->sp_fd[0] >= 0); 199 close(spctx->sp_fd[0]); 200 spctx->sp_fd[0] = -1; 201 PJDLOG_ASSERT(spctx->sp_fd[1] >= 0); 202 close(spctx->sp_fd[1]); 203 spctx->sp_fd[1] = -1; 204 break; 205 case SP_SIDE_CLIENT: 206 PJDLOG_ASSERT(spctx->sp_fd[0] >= 0); 207 close(spctx->sp_fd[0]); 208 spctx->sp_fd[0] = -1; 209 PJDLOG_ASSERT(spctx->sp_fd[1] == -1); 210 break; 211 case SP_SIDE_SERVER: 212 PJDLOG_ASSERT(spctx->sp_fd[1] >= 0); 213 close(spctx->sp_fd[1]); 214 spctx->sp_fd[1] = -1; 215 PJDLOG_ASSERT(spctx->sp_fd[0] == -1); 216 break; 217 default: 218 PJDLOG_ABORT("Invalid socket side (%d).", spctx->sp_side); 219 } 220 221 spctx->sp_magic = 0; 222 free(spctx); 223 } 224 225 static struct proto sp_proto = { 226 .prt_name = "socketpair", 227 .prt_client = sp_client, 228 .prt_send = sp_send, 229 .prt_recv = sp_recv, 230 .prt_descriptor = sp_descriptor, 231 .prt_close = sp_close 232 }; 233 234 static __constructor void 235 sp_ctor(void) 236 { 237 238 proto_register(&sp_proto, false); 239 } 240