1 /*- 2 * Copyright (c) 2005 Robert N. M. Watson 3 * Copyright (c) 2015 Mark Johnston 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 __FBSDID("$FreeBSD$"); 30 31 #include <sys/types.h> 32 #include <sys/socket.h> 33 #include <sys/stat.h> 34 #include <sys/sysctl.h> 35 #include <sys/un.h> 36 37 #include <errno.h> 38 #include <fcntl.h> 39 #include <limits.h> 40 #include <stdio.h> 41 #include <stdlib.h> 42 #include <string.h> 43 #include <unistd.h> 44 45 #include <atf-c.h> 46 47 /* 48 * UNIX domain sockets allow file descriptors to be passed via "ancillary 49 * data", or control messages. This regression test is intended to exercise 50 * this facility, both performing some basic tests that it operates, and also 51 * causing some kernel edge cases to execute, such as garbage collection when 52 * there are cyclic file descriptor references. Right now we test only with 53 * stream sockets, but ideally we'd also test with datagram sockets. 54 */ 55 56 static void 57 domainsocketpair(int *fdp) 58 { 59 60 ATF_REQUIRE_MSG(socketpair(PF_UNIX, SOCK_STREAM, 0, fdp) != -1, 61 "socketpair(PF_UNIX, SOCK_STREAM) failed: %s", strerror(errno)); 62 } 63 64 static void 65 closesocketpair(int *fdp) 66 { 67 68 close(fdp[0]); 69 close(fdp[1]); 70 } 71 72 static void 73 devnull(int *fdp) 74 { 75 int fd; 76 77 fd = open("/dev/null", O_RDONLY); 78 ATF_REQUIRE_MSG(fd != -1, "open failed: %s", strerror(errno)); 79 *fdp = fd; 80 } 81 82 static void 83 tempfile(int *fdp) 84 { 85 char path[PATH_MAX]; 86 int fd; 87 88 snprintf(path, PATH_MAX, "%s/unix_passfd.XXXXXXXXXXXXXXX", 89 getenv("TMPDIR") == NULL ? "/tmp" : getenv("TMPDIR")); 90 fd = mkstemp(path); 91 ATF_REQUIRE_MSG(fd != -1, "mkstemp(%s) failed", path); 92 (void)unlink(path); 93 *fdp = fd; 94 } 95 96 static void 97 dofstat(int fd, struct stat *sb) 98 { 99 100 ATF_REQUIRE_MSG(fstat(fd, sb) == 0, 101 "fstat failed: %s", strerror(errno)); 102 } 103 104 static int 105 getnfds(void) 106 { 107 size_t len; 108 int mib[4], n, rc; 109 110 len = sizeof(n); 111 mib[0] = CTL_KERN; 112 mib[1] = KERN_PROC; 113 mib[2] = KERN_PROC_NFDS; 114 mib[3] = 0; 115 116 rc = sysctl(mib, 4, &n, &len, NULL, 0); 117 ATF_REQUIRE_MSG(rc != -1, "sysctl(KERN_PROC_NFDS) failed"); 118 return (n); 119 } 120 121 static void 122 samefile(struct stat *sb1, struct stat *sb2) 123 { 124 125 ATF_REQUIRE_MSG(sb1->st_dev == sb2->st_dev, "different device"); 126 ATF_REQUIRE_MSG(sb1->st_ino == sb2->st_ino, "different inode"); 127 } 128 129 static void 130 sendfd_payload(int sockfd, int send_fd, void *payload, size_t paylen) 131 { 132 struct iovec iovec; 133 char message[CMSG_SPACE(sizeof(int))]; 134 struct cmsghdr *cmsghdr; 135 struct msghdr msghdr; 136 ssize_t len; 137 138 bzero(&msghdr, sizeof(msghdr)); 139 bzero(&message, sizeof(message)); 140 141 msghdr.msg_control = message; 142 msghdr.msg_controllen = sizeof(message); 143 144 iovec.iov_base = payload; 145 iovec.iov_len = paylen; 146 147 msghdr.msg_iov = &iovec; 148 msghdr.msg_iovlen = 1; 149 150 cmsghdr = (struct cmsghdr *)(void *)message; 151 cmsghdr->cmsg_len = CMSG_LEN(sizeof(int)); 152 cmsghdr->cmsg_level = SOL_SOCKET; 153 cmsghdr->cmsg_type = SCM_RIGHTS; 154 memcpy(CMSG_DATA(cmsghdr), &send_fd, sizeof(int)); 155 156 len = sendmsg(sockfd, &msghdr, 0); 157 ATF_REQUIRE_MSG(len != -1, "sendmsg failed: %s", strerror(errno)); 158 ATF_REQUIRE_MSG((size_t)len == paylen, 159 "sendmsg: %zd messages sent; expected: %zu; %s", len, paylen, 160 strerror(errno)); 161 } 162 163 static void 164 sendfd(int sockfd, int send_fd) 165 { 166 char ch = 0; 167 168 return (sendfd_payload(sockfd, send_fd, &ch, sizeof(ch))); 169 } 170 171 static void 172 recvfd_payload(int sockfd, int *recv_fd, void *buf, size_t buflen) 173 { 174 struct cmsghdr *cmsghdr; 175 char message[CMSG_SPACE(SOCKCREDSIZE(CMGROUP_MAX)) + sizeof(int)]; 176 struct msghdr msghdr; 177 struct iovec iovec; 178 ssize_t len; 179 180 bzero(&msghdr, sizeof(msghdr)); 181 182 msghdr.msg_control = message; 183 msghdr.msg_controllen = sizeof(message); 184 185 iovec.iov_base = buf; 186 iovec.iov_len = buflen; 187 188 msghdr.msg_iov = &iovec; 189 msghdr.msg_iovlen = 1; 190 191 len = recvmsg(sockfd, &msghdr, 0); 192 ATF_REQUIRE_MSG(len != -1, "recvmsg failed: %s", strerror(errno)); 193 ATF_REQUIRE_MSG((size_t)len == buflen, 194 "recvmsg: %zd bytes received; expected %zd", len, buflen); 195 196 cmsghdr = CMSG_FIRSTHDR(&msghdr); 197 ATF_REQUIRE_MSG(cmsghdr != NULL, 198 "recvmsg: did not receive control message"); 199 *recv_fd = -1; 200 for (; cmsghdr != NULL; cmsghdr = CMSG_NXTHDR(&msghdr, cmsghdr)) { 201 if (cmsghdr->cmsg_level == SOL_SOCKET && 202 cmsghdr->cmsg_type == SCM_RIGHTS && 203 cmsghdr->cmsg_len == CMSG_LEN(sizeof(int))) { 204 memcpy(recv_fd, CMSG_DATA(cmsghdr), sizeof(int)); 205 ATF_REQUIRE(*recv_fd != -1); 206 } 207 } 208 ATF_REQUIRE_MSG(*recv_fd != -1, 209 "recvmsg: did not receive single-fd message"); 210 } 211 212 static void 213 recvfd(int sockfd, int *recv_fd) 214 { 215 char ch = 0; 216 217 return (recvfd_payload(sockfd, recv_fd, &ch, sizeof(ch))); 218 } 219 220 /* 221 * Put a temporary file into a UNIX domain socket, then take it out and make 222 * sure it's the same file. First time around, don't close the reference 223 * after sending. 224 */ 225 ATF_TC_WITHOUT_HEAD(simple_send_fd); 226 ATF_TC_BODY(simple_send_fd, tc) 227 { 228 struct stat getfd_stat, putfd_stat; 229 int fd[2], getfd, putfd; 230 231 domainsocketpair(fd); 232 tempfile(&putfd); 233 dofstat(putfd, &putfd_stat); 234 sendfd(fd[0], putfd); 235 recvfd(fd[1], &getfd); 236 dofstat(getfd, &getfd_stat); 237 samefile(&putfd_stat, &getfd_stat); 238 close(putfd); 239 close(getfd); 240 closesocketpair(fd); 241 } 242 243 /* 244 * Same as simple_send_fd, only close the file reference after sending, so that 245 * the only reference is the descriptor in the UNIX domain socket buffer. 246 */ 247 ATF_TC_WITHOUT_HEAD(send_and_close); 248 ATF_TC_BODY(send_and_close, tc) 249 { 250 struct stat getfd_stat, putfd_stat; 251 int fd[2], getfd, putfd; 252 253 domainsocketpair(fd); 254 tempfile(&putfd); 255 dofstat(putfd, &putfd_stat); 256 sendfd(fd[0], putfd); 257 close(putfd); 258 recvfd(fd[1], &getfd); 259 dofstat(getfd, &getfd_stat); 260 samefile(&putfd_stat, &getfd_stat); 261 close(getfd); 262 closesocketpair(fd); 263 } 264 265 /* 266 * Put a temporary file into a UNIX domain socket, then close both endpoints 267 * causing garbage collection to kick off. 268 */ 269 ATF_TC_WITHOUT_HEAD(send_and_cancel); 270 ATF_TC_BODY(send_and_cancel, tc) 271 { 272 int fd[2], putfd; 273 274 domainsocketpair(fd); 275 tempfile(&putfd); 276 sendfd(fd[0], putfd); 277 close(putfd); 278 closesocketpair(fd); 279 } 280 281 /* 282 * Send two files. Then receive them. Make sure they are returned in the 283 * right order, and both get there. 284 */ 285 ATF_TC_WITHOUT_HEAD(two_files); 286 ATF_TC_BODY(two_files, tc) 287 { 288 struct stat getfd_1_stat, getfd_2_stat, putfd_1_stat, putfd_2_stat; 289 int fd[2], getfd_1, getfd_2, putfd_1, putfd_2; 290 291 domainsocketpair(fd); 292 tempfile(&putfd_1); 293 tempfile(&putfd_2); 294 dofstat(putfd_1, &putfd_1_stat); 295 dofstat(putfd_2, &putfd_2_stat); 296 sendfd(fd[0], putfd_1); 297 sendfd(fd[0], putfd_2); 298 close(putfd_1); 299 close(putfd_2); 300 recvfd(fd[1], &getfd_1); 301 recvfd(fd[1], &getfd_2); 302 dofstat(getfd_1, &getfd_1_stat); 303 dofstat(getfd_2, &getfd_2_stat); 304 samefile(&putfd_1_stat, &getfd_1_stat); 305 samefile(&putfd_2_stat, &getfd_2_stat); 306 close(getfd_1); 307 close(getfd_2); 308 closesocketpair(fd); 309 } 310 311 /* 312 * Big bundling test. Send an endpoint of the UNIX domain socket over itself, 313 * closing the door behind it. 314 */ 315 ATF_TC_WITHOUT_HEAD(bundle); 316 ATF_TC_BODY(bundle, tc) 317 { 318 int fd[2], getfd; 319 320 domainsocketpair(fd); 321 322 sendfd(fd[0], fd[0]); 323 close(fd[0]); 324 recvfd(fd[1], &getfd); 325 close(getfd); 326 close(fd[1]); 327 } 328 329 /* 330 * Big bundling test part two: Send an endpoint of the UNIX domain socket over 331 * itself, close the door behind it, and never remove it from the other end. 332 */ 333 ATF_TC_WITHOUT_HEAD(bundle_cancel); 334 ATF_TC_BODY(bundle_cancel, tc) 335 { 336 int fd[2]; 337 338 domainsocketpair(fd); 339 sendfd(fd[0], fd[0]); 340 sendfd(fd[1], fd[0]); 341 closesocketpair(fd); 342 } 343 344 /* 345 * Test for PR 151758: Send an character device over the UNIX domain socket 346 * and then close both sockets to orphan the device. 347 */ 348 ATF_TC_WITHOUT_HEAD(devfs_orphan); 349 ATF_TC_BODY(devfs_orphan, tc) 350 { 351 int fd[2], putfd; 352 353 domainsocketpair(fd); 354 devnull(&putfd); 355 sendfd(fd[0], putfd); 356 close(putfd); 357 closesocketpair(fd); 358 } 359 360 #define LOCAL_SENDSPACE_SYSCTL "net.local.stream.sendspace" 361 362 /* 363 * Test for PR 181741. Receiver sets LOCAL_CREDS, and kernel prepends a 364 * control message to the data. Sender sends large payload. 365 * Payload + SCM_RIGHTS + LOCAL_CREDS hit socket buffer limit, and receiver 366 * receives truncated data. 367 */ 368 ATF_TC_WITHOUT_HEAD(rights_creds_payload); 369 ATF_TC_BODY(rights_creds_payload, tc) 370 { 371 const int on = 1; 372 u_long sendspace; 373 size_t len; 374 void *buf; 375 int fd[2], getfd, putfd, rc; 376 377 atf_tc_expect_fail("PR 181741: Packet loss when 'control' messages " 378 "are present with large data"); 379 380 len = sizeof(sendspace); 381 rc = sysctlbyname(LOCAL_SENDSPACE_SYSCTL, &sendspace, 382 &len, NULL, 0); 383 ATF_REQUIRE_MSG(rc != -1, 384 "sysctl %s failed: %s", LOCAL_SENDSPACE_SYSCTL, strerror(errno)); 385 386 buf = calloc(1, sendspace); 387 ATF_REQUIRE(buf != NULL); 388 389 domainsocketpair(fd); 390 rc = setsockopt(fd[1], 0, LOCAL_CREDS, &on, sizeof(on)); 391 ATF_REQUIRE_MSG(rc != -1, "setsockopt(LOCAL_CREDS) failed: %s", 392 strerror(errno)); 393 tempfile(&putfd); 394 sendfd_payload(fd[0], putfd, buf, sendspace); 395 recvfd_payload(fd[1], &getfd, buf, sendspace); 396 close(putfd); 397 close(getfd); 398 closesocketpair(fd); 399 } 400 401 /* 402 * Test for PR 131876. Receiver uses a control message buffer that is too 403 * small for the incoming SCM_RIGHTS message, so the message is truncated. 404 * The kernel must not leak the copied right into the receiver's namespace. 405 */ 406 ATF_TC_WITHOUT_HEAD(truncated_rights); 407 ATF_TC_BODY(truncated_rights, tc) 408 { 409 struct iovec iovec; 410 struct msghdr msghdr; 411 char buf[16], message[CMSG_SPACE(0)]; 412 ssize_t len; 413 int fd[2], nfds, putfd; 414 415 atf_tc_expect_fail("PR 131876: " 416 "FD leak when 'control' message is truncated"); 417 418 memset(buf, 42, sizeof(buf)); 419 domainsocketpair(fd); 420 devnull(&putfd); 421 nfds = getnfds(); 422 423 sendfd_payload(fd[0], putfd, buf, sizeof(buf)); 424 425 bzero(&msghdr, sizeof(msghdr)); 426 bzero(message, sizeof(message)); 427 428 iovec.iov_base = buf; 429 iovec.iov_len = sizeof(buf); 430 msghdr.msg_control = message; 431 msghdr.msg_controllen = sizeof(message); 432 msghdr.msg_iov = &iovec; 433 msghdr.msg_iovlen = 1; 434 435 len = recvmsg(fd[1], &msghdr, 0); 436 ATF_REQUIRE_MSG(len != -1, "recvmsg failed: %s", strerror(errno)); 437 ATF_REQUIRE_MSG((size_t)len == sizeof(buf), 438 "recvmsg: %zd bytes received; expected %zd", len, sizeof(buf)); 439 for (size_t i = 0; i < sizeof(buf); i++) 440 ATF_REQUIRE_MSG(buf[i] == 42, "unexpected buffer contents"); 441 442 ATF_REQUIRE_MSG((msghdr.msg_flags & MSG_CTRUNC) != 0, 443 "MSG_CTRUNC not set after truncation"); 444 ATF_REQUIRE(getnfds() == nfds); 445 446 close(putfd); 447 closesocketpair(fd); 448 } 449 450 ATF_TP_ADD_TCS(tp) 451 { 452 453 ATF_TP_ADD_TC(tp, simple_send_fd); 454 ATF_TP_ADD_TC(tp, send_and_close); 455 ATF_TP_ADD_TC(tp, send_and_cancel); 456 ATF_TP_ADD_TC(tp, two_files); 457 ATF_TP_ADD_TC(tp, bundle); 458 ATF_TP_ADD_TC(tp, bundle_cancel); 459 ATF_TP_ADD_TC(tp, devfs_orphan); 460 ATF_TP_ADD_TC(tp, rights_creds_payload); 461 ATF_TP_ADD_TC(tp, truncated_rights); 462 463 return (atf_no_error()); 464 } 465