1 /* $OpenBSD: unfdpass.c,v 1.19 2017/01/26 04:45:46 benno Exp $ */ 2 /* $NetBSD: unfdpass.c,v 1.3 1998/06/24 23:51:30 thorpej Exp $ */ 3 4 /*- 5 * Copyright (c) 1998 The NetBSD Foundation, Inc. 6 * All rights reserved. 7 * 8 * This code is derived from software contributed to The NetBSD Foundation 9 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 10 * NASA Ames Research Center. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 23 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 24 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 25 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 30 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 31 * POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 /* 35 * Test passing of file descriptors over Unix domain sockets and socketpairs. 36 */ 37 38 #include <sys/param.h> 39 #include <sys/socket.h> 40 #include <sys/time.h> 41 #include <sys/wait.h> 42 #include <sys/un.h> 43 #include <err.h> 44 #include <errno.h> 45 #include <fcntl.h> 46 #include <signal.h> 47 #include <stdio.h> 48 #include <stdlib.h> 49 #include <string.h> 50 #include <unistd.h> 51 52 #define SOCK_NAME "test-sock" 53 54 int main(int, char *[]); 55 void child(int, int); 56 void catch_sigchld(int); 57 58 /* ARGSUSED */ 59 int 60 main(int argc, char *argv[]) 61 { 62 struct msghdr msg; 63 int sock, pfd[2], fd, i; 64 int listensock = -1; 65 char fname[16], buf[64]; 66 struct cmsghdr *cmp; 67 int *files = NULL; 68 struct sockaddr_un sun, csun; 69 int csunlen; 70 pid_t pid; 71 union { 72 struct cmsghdr hdr; 73 char buf[CMSG_SPACE(sizeof(int) * 3)]; 74 } cmsgbuf; 75 int pflag; 76 int type = SOCK_STREAM; 77 extern char *__progname; 78 79 pflag = 0; 80 while ((i = getopt(argc, argv, "pq")) != -1) { 81 switch (i) { 82 case 'p': 83 pflag = 1; 84 break; 85 case 'q': 86 type = SOCK_SEQPACKET; 87 break; 88 default: 89 fprintf(stderr, "usage: %s [-p]\n", __progname); 90 exit(1); 91 } 92 } 93 94 /* 95 * Create the test files. 96 */ 97 for (i = 0; i < 3; i++) { 98 (void) snprintf(fname, sizeof fname, "file%d", i + 1); 99 if ((fd = open(fname, O_WRONLY|O_CREAT|O_TRUNC, 0666)) == -1) 100 err(1, "open %s", fname); 101 (void) snprintf(buf, sizeof buf, "This is file %d.\n", i + 1); 102 if (write(fd, buf, strlen(buf)) != (ssize_t) strlen(buf)) 103 err(1, "write %s", fname); 104 (void) close(fd); 105 } 106 107 if (pflag) { 108 /* 109 * Create the socketpair 110 */ 111 if (socketpair(PF_LOCAL, type, 0, pfd) == -1) 112 err(1, "socketpair"); 113 } else { 114 /* 115 * Create the listen socket. 116 */ 117 if ((listensock = socket(PF_LOCAL, type, 0)) == -1) 118 err(1, "socket"); 119 120 (void) unlink(SOCK_NAME); 121 (void) memset(&sun, 0, sizeof(sun)); 122 sun.sun_family = AF_LOCAL; 123 (void) strlcpy(sun.sun_path, SOCK_NAME, sizeof sun.sun_path); 124 125 if (bind(listensock, (struct sockaddr *)&sun, sizeof(sun)) == -1) 126 err(1, "bind"); 127 128 if (listen(listensock, 1) == -1) 129 err(1, "listen"); 130 pfd[0] = pfd[1] = -1; 131 } 132 133 /* 134 * Create the sender. 135 */ 136 (void) signal(SIGCHLD, catch_sigchld); 137 pid = fork(); 138 switch (pid) { 139 case -1: 140 err(1, "fork"); 141 /* NOTREACHED */ 142 143 case 0: 144 if (pfd[0] != -1) 145 close(pfd[0]); 146 child(pfd[1], type); 147 /* NOTREACHED */ 148 } 149 150 if (pfd[0] != -1) { 151 close(pfd[1]); 152 sock = pfd[0]; 153 } else { 154 /* 155 * Wait for the sender to connect. 156 */ 157 if ((sock = accept(listensock, (struct sockaddr *)&csun, 158 &csunlen)) == -1) 159 err(1, "accept"); 160 } 161 162 /* 163 * Give sender a chance to run. We will get going again 164 * once the SIGCHLD arrives. 165 */ 166 (void) sleep(10); 167 168 /* 169 * Grab the descriptors passed to us. 170 */ 171 (void) memset(&msg, 0, sizeof(msg)); 172 msg.msg_control = &cmsgbuf.buf; 173 msg.msg_controllen = sizeof(cmsgbuf.buf); 174 175 if (recvmsg(sock, &msg, 0) < 0) 176 err(1, "recvmsg"); 177 178 (void) close(sock); 179 180 if (msg.msg_controllen == 0) 181 errx(1, "no control messages received"); 182 183 if (msg.msg_flags & MSG_CTRUNC) 184 errx(1, "lost control message data"); 185 186 for (cmp = CMSG_FIRSTHDR(&msg); cmp != NULL; 187 cmp = CMSG_NXTHDR(&msg, cmp)) { 188 if (cmp->cmsg_level != SOL_SOCKET) 189 errx(1, "bad control message level %d", 190 cmp->cmsg_level); 191 192 switch (cmp->cmsg_type) { 193 case SCM_RIGHTS: 194 if (cmp->cmsg_len != CMSG_LEN(sizeof(int) * 3)) 195 errx(1, "bad fd control message length %d", 196 cmp->cmsg_len); 197 198 files = (int *)CMSG_DATA(cmp); 199 break; 200 201 default: 202 errx(1, "unexpected control message"); 203 /* NOTREACHED */ 204 } 205 } 206 207 /* 208 * Read the files and print their contents. 209 */ 210 if (files == NULL) 211 warnx("didn't get fd control message"); 212 else { 213 for (i = 0; i < 3; i++) { 214 (void) memset(buf, 0, sizeof(buf)); 215 if (read(files[i], buf, sizeof(buf)) <= 0) 216 err(1, "read file %d (%d)", i + 1, files[i]); 217 printf("%s", buf); 218 } 219 } 220 221 /* 222 * All done! 223 */ 224 exit(0); 225 } 226 227 void 228 catch_sigchld(sig) 229 int sig; 230 { 231 int save_errno = errno; 232 int status; 233 234 (void) wait(&status); 235 errno = save_errno; 236 } 237 238 void 239 child(int sock, int type) 240 { 241 struct msghdr msg; 242 char fname[16]; 243 struct cmsghdr *cmp; 244 int i, fd; 245 struct sockaddr_un sun; 246 union { 247 struct cmsghdr hdr; 248 char buf[CMSG_SPACE(sizeof(int) * 3)]; 249 } cmsgbuf; 250 int *files; 251 252 /* 253 * Create socket if needed and connect to the receiver. 254 */ 255 if (sock == -1) { 256 if ((sock = socket(PF_LOCAL, type, 0)) == -1) 257 err(1, "child socket"); 258 259 (void) memset(&sun, 0, sizeof(sun)); 260 sun.sun_family = AF_LOCAL; 261 (void) strlcpy(sun.sun_path, SOCK_NAME, sizeof sun.sun_path); 262 263 if (connect(sock, (struct sockaddr *)&sun, sizeof(sun)) == -1) 264 err(1, "child connect"); 265 } 266 267 (void) memset(&msg, 0, sizeof(msg)); 268 msg.msg_control = &cmsgbuf.buf; 269 msg.msg_controllen = sizeof(cmsgbuf.buf); 270 271 cmp = CMSG_FIRSTHDR(&msg); 272 cmp->cmsg_len = CMSG_LEN(sizeof(int) * 3); 273 cmp->cmsg_level = SOL_SOCKET; 274 cmp->cmsg_type = SCM_RIGHTS; 275 276 /* 277 * Open the files again, and pass them to the parent over the socket. 278 */ 279 files = (int *)CMSG_DATA(cmp); 280 for (i = 0; i < 3; i++) { 281 (void) snprintf(fname, sizeof fname, "file%d", i + 1); 282 if ((fd = open(fname, O_RDONLY, 0666)) == -1) 283 err(1, "child open %s", fname); 284 files[i] = fd; 285 } 286 287 if (sendmsg(sock, &msg, 0)) 288 err(1, "child sendmsg"); 289 290 /* 291 * All done! 292 */ 293 exit(0); 294 } 295