1 /* $OpenBSD: unfdpass.c,v 1.23 2023/03/08 04:43:06 guenther 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/socket.h> 39 #include <sys/time.h> 40 #include <sys/wait.h> 41 #include <sys/un.h> 42 #include <err.h> 43 #include <errno.h> 44 #include <fcntl.h> 45 #include <signal.h> 46 #include <stdio.h> 47 #include <stdlib.h> 48 #include <string.h> 49 #include <unistd.h> 50 51 #define SOCK_NAME "test-sock" 52 53 int main(int, char *[]); 54 void child(int, int, int); 55 void catch_sigchld(int); 56 57 int 58 main(int argc, char *argv[]) 59 { 60 struct msghdr msg; 61 int sock, pfd[2], fd, i; 62 int listensock = -1; 63 char fname[16], buf[64]; 64 struct cmsghdr *cmp; 65 int *files = NULL; 66 struct sockaddr_un sun, csun; 67 int csunlen; 68 pid_t pid; 69 union { 70 struct cmsghdr hdr; 71 char buf[CMSG_SPACE(sizeof(int) * 3)]; 72 } cmsgbuf; 73 int pflag, oflag, rflag; 74 int type = SOCK_STREAM; 75 extern char *__progname; 76 77 pflag = 0; 78 oflag = 0; 79 rflag = 0; 80 while ((i = getopt(argc, argv, "opqr")) != -1) { 81 switch (i) { 82 case 'o': 83 oflag = 1; 84 break; 85 case 'p': 86 pflag = 1; 87 break; 88 case 'q': 89 type = SOCK_SEQPACKET; 90 break; 91 case 'r': 92 rflag = 1; 93 break; 94 default: 95 fprintf(stderr, "usage: %s [-opqr]\n", __progname); 96 exit(1); 97 } 98 } 99 100 /* 101 * Create the test files. 102 */ 103 for (i = 0; i < 5; i++) { 104 (void) snprintf(fname, sizeof fname, "file%d", i + 1); 105 if ((fd = open(fname, O_WRONLY|O_CREAT|O_TRUNC, 0666)) == -1) 106 err(1, "open %s", fname); 107 (void) snprintf(buf, sizeof buf, "This is file %d.\n", i + 1); 108 if (write(fd, buf, strlen(buf)) != (ssize_t) strlen(buf)) 109 err(1, "write %s", fname); 110 (void) close(fd); 111 } 112 113 if (pflag) { 114 /* 115 * Create the socketpair 116 */ 117 if (socketpair(PF_LOCAL, type, 0, pfd) == -1) 118 err(1, "socketpair"); 119 } else { 120 /* 121 * Create the listen socket. 122 */ 123 if ((listensock = socket(PF_LOCAL, type, 0)) == -1) 124 err(1, "socket"); 125 126 (void) unlink(SOCK_NAME); 127 (void) memset(&sun, 0, sizeof(sun)); 128 sun.sun_family = AF_LOCAL; 129 (void) strlcpy(sun.sun_path, SOCK_NAME, sizeof sun.sun_path); 130 131 if (bind(listensock, (struct sockaddr *)&sun, sizeof(sun)) == -1) 132 err(1, "bind"); 133 134 if (listen(listensock, 1) == -1) 135 err(1, "listen"); 136 pfd[0] = pfd[1] = -1; 137 } 138 139 /* 140 * Create the sender. 141 */ 142 (void) signal(SIGCHLD, catch_sigchld); 143 pid = fork(); 144 switch (pid) { 145 case -1: 146 err(1, "fork"); 147 /* NOTREACHED */ 148 149 case 0: 150 if (pfd[0] != -1) 151 close(pfd[0]); 152 child(pfd[1], type, oflag); 153 /* NOTREACHED */ 154 } 155 156 if (pfd[0] != -1) { 157 close(pfd[1]); 158 sock = pfd[0]; 159 } else { 160 /* 161 * Wait for the sender to connect. 162 */ 163 if ((sock = accept(listensock, (struct sockaddr *)&csun, 164 &csunlen)) == -1) 165 err(1, "accept"); 166 } 167 168 /* 169 * Give sender a chance to run. We will get going again 170 * once the SIGCHLD arrives. 171 */ 172 (void) sleep(10); 173 174 if (rflag) { 175 if (read(sock, buf, sizeof(buf)) < 0) 176 err(1, "read"); 177 printf("read successfully returned\n"); 178 exit(0); 179 } 180 181 /* 182 * Grab the descriptors passed to us. 183 */ 184 memset(&msg, 0, sizeof(msg)); 185 msg.msg_control = &cmsgbuf.buf; 186 msg.msg_controllen = sizeof(cmsgbuf.buf); 187 188 if (recvmsg(sock, &msg, 0) < 0) { 189 if (errno == EMSGSIZE) { 190 printf("recvmsg returned EMSGSIZE\n"); 191 exit(0); 192 } else 193 err(1, "recvmsg"); 194 } 195 196 (void) close(sock); 197 198 if (msg.msg_controllen == 0) 199 errx(1, "no control messages received"); 200 201 if (msg.msg_flags & MSG_CTRUNC) 202 errx(1, "lost control message data"); 203 204 for (cmp = CMSG_FIRSTHDR(&msg); cmp != NULL; 205 cmp = CMSG_NXTHDR(&msg, cmp)) { 206 if (cmp->cmsg_level != SOL_SOCKET) 207 errx(1, "bad control message level %d", 208 cmp->cmsg_level); 209 210 switch (cmp->cmsg_type) { 211 case SCM_RIGHTS: 212 if (cmp->cmsg_len != CMSG_LEN(sizeof(int) * 3)) 213 errx(1, "bad fd control message length %d", 214 cmp->cmsg_len); 215 216 files = (int *)CMSG_DATA(cmp); 217 break; 218 219 default: 220 errx(1, "unexpected control message"); 221 /* NOTREACHED */ 222 } 223 } 224 225 /* 226 * Read the files and print their contents. 227 */ 228 if (files == NULL) 229 warnx("didn't get fd control message"); 230 else { 231 for (i = 0; i < 3; i++) { 232 (void) memset(buf, 0, sizeof(buf)); 233 if (read(files[i], buf, sizeof(buf)) <= 0) 234 err(1, "read file %d (%d)", i + 1, files[i]); 235 printf("%s", buf); 236 } 237 } 238 239 /* 240 * All done! 241 */ 242 exit(0); 243 } 244 245 void 246 catch_sigchld(sig) 247 int sig; 248 { 249 int save_errno = errno; 250 int status; 251 252 (void) wait(&status); 253 errno = save_errno; 254 } 255 256 void 257 child(int sock, int type, int oflag) 258 { 259 struct msghdr msg; 260 char fname[16]; 261 struct cmsghdr *cmp; 262 int i, fd, nfds = 3; 263 struct sockaddr_un sun; 264 size_t len; 265 char *cmsgbuf; 266 int *files; 267 268 /* 269 * Create socket if needed and connect to the receiver. 270 */ 271 if (sock == -1) { 272 if ((sock = socket(PF_LOCAL, type, 0)) == -1) 273 err(1, "child socket"); 274 275 (void) memset(&sun, 0, sizeof(sun)); 276 sun.sun_family = AF_LOCAL; 277 (void) strlcpy(sun.sun_path, SOCK_NAME, sizeof sun.sun_path); 278 279 if (connect(sock, (struct sockaddr *)&sun, sizeof(sun)) == -1) 280 err(1, "child connect"); 281 } 282 283 if (oflag) 284 nfds = 5; 285 len = CMSG_SPACE(sizeof(int) * nfds); 286 if ((cmsgbuf = malloc(len)) == NULL) 287 err(1, "child"); 288 289 (void) memset(&msg, 0, sizeof(msg)); 290 msg.msg_control = cmsgbuf; 291 msg.msg_controllen = len; 292 293 cmp = CMSG_FIRSTHDR(&msg); 294 cmp->cmsg_len = CMSG_LEN((sizeof(int) * nfds)); 295 cmp->cmsg_level = SOL_SOCKET; 296 cmp->cmsg_type = SCM_RIGHTS; 297 298 /* 299 * Open the files again, and pass them to the parent over the socket. 300 */ 301 files = (int *)CMSG_DATA(cmp); 302 for (i = 0; i < nfds; i++) { 303 (void) snprintf(fname, sizeof fname, "file%d", i + 1); 304 if ((fd = open(fname, O_RDONLY)) == -1) 305 err(1, "child open %s", fname); 306 files[i] = fd; 307 } 308 309 if (sendmsg(sock, &msg, 0)) 310 err(1, "child sendmsg"); 311 312 /* 313 * All done! 314 */ 315 exit(0); 316 } 317