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