1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2022 Gleb Smirnoff <glebius@FreeBSD.org> 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/time.h> 29 #include <sys/event.h> 30 #include <sys/ioctl.h> 31 #include <sys/select.h> 32 #include <sys/socket.h> 33 #include <sys/sysctl.h> 34 #include <sys/un.h> 35 #include <aio.h> 36 #include <errno.h> 37 #include <fcntl.h> 38 #include <signal.h> 39 #include <stdlib.h> 40 41 #include <atf-c.h> 42 43 static struct itimerval itv = { 44 .it_interval = { 0, 0 }, 45 .it_value = { 1, 0 }, /* one second */ 46 }; 47 static sig_atomic_t timer_done = 0; 48 static void 49 sigalarm(int sig __unused) 50 { 51 52 timer_done = 1; 53 } 54 55 static struct sigaction sigact = { 56 .sa_handler = sigalarm, 57 }; 58 59 static struct sockaddr_un sun = { 60 .sun_family = AF_LOCAL, 61 .sun_len = sizeof(sun), 62 .sun_path = "unix_dgram_listener", 63 }; 64 65 /* 66 * Fill socket to a state when next send(len) would fail. 67 * 68 * Note that every datagram is prepended with sender address, 69 * size of struct sockaddr. 70 */ 71 static void 72 fill(int fd, void *buf, ssize_t len) 73 { 74 unsigned long recvspace; 75 size_t llen = sizeof(unsigned long); 76 ssize_t sent; 77 78 ATF_REQUIRE(sysctlbyname("net.local.dgram.recvspace", &recvspace, 79 &llen, NULL, 0) == 0); 80 for (sent = 0; 81 sent + len + sizeof(struct sockaddr) < recvspace; 82 sent += len + sizeof(struct sockaddr)) 83 ATF_REQUIRE(send(fd, buf, len, 0) == len); 84 } 85 86 ATF_TC_WITHOUT_HEAD(basic); 87 ATF_TC_BODY(basic, tc) 88 { 89 struct msghdr msg; 90 struct iovec iov[1]; 91 unsigned long maxdgram; 92 size_t llen = sizeof(unsigned long); 93 int fd[2]; 94 char *buf; 95 96 /* Allocate and initialize: 97 * - fd[0] to send, fd[1] to receive 98 * - buf[maxdgram] for data 99 */ 100 ATF_REQUIRE(sysctlbyname("net.local.dgram.maxdgram", &maxdgram, 101 &llen, NULL, 0) == 0); 102 ATF_REQUIRE(socketpair(PF_UNIX, SOCK_DGRAM, 0, fd) != -1); 103 buf = malloc(maxdgram + 1); 104 ATF_REQUIRE(buf); 105 msg = (struct msghdr ){ 106 .msg_iov = iov, 107 .msg_iovlen = 1, 108 }; 109 iov[0] = (struct iovec ){ 110 .iov_base = buf, 111 }; 112 113 /* Fail to send > maxdgram. */ 114 ATF_REQUIRE(send(fd[0], buf, maxdgram + 1, 0) == -1); 115 ATF_REQUIRE(errno == EMSGSIZE); 116 117 /* Send maxdgram. */ 118 ATF_REQUIRE(send(fd[0], buf, maxdgram, 0) == (ssize_t)maxdgram); 119 120 /* Exercise MSG_PEEK, full and truncated.. */ 121 ATF_REQUIRE(recv(fd[1], buf, maxdgram, MSG_PEEK) == (ssize_t)maxdgram); 122 iov[0].iov_len = 42; 123 ATF_REQUIRE(recvmsg(fd[1], &msg, MSG_PEEK) == 42); 124 ATF_REQUIRE(msg.msg_flags == (MSG_PEEK | MSG_TRUNC)); 125 126 /* Receive maxdgram. */ 127 iov[0].iov_len = maxdgram; 128 ATF_REQUIRE(recvmsg(fd[1], &msg, 0) == (ssize_t)maxdgram); 129 ATF_REQUIRE(msg.msg_flags == 0); 130 131 /* Receive truncated message. */ 132 ATF_REQUIRE(send(fd[0], buf, maxdgram, 0) == (ssize_t)maxdgram); 133 iov[0].iov_len = maxdgram / 2; 134 ATF_REQUIRE(recvmsg(fd[1], &msg, 0) == (ssize_t)maxdgram / 2); 135 ATF_REQUIRE(msg.msg_flags == MSG_TRUNC); 136 137 /* Empty: block. */ 138 ATF_REQUIRE(sigaction(SIGALRM, &sigact, NULL) == 0); 139 ATF_REQUIRE(timer_done == 0); 140 ATF_REQUIRE(setitimer(ITIMER_REAL, &itv, NULL) == 0); 141 ATF_REQUIRE(recv(fd[1], buf, maxdgram, 0) == -1); 142 ATF_REQUIRE(errno == EINTR); 143 ATF_REQUIRE(timer_done == 1); 144 145 /* Don't block with MSG_DONTWAIT. */ 146 ATF_REQUIRE(recv(fd[1], buf, maxdgram, MSG_DONTWAIT) == -1); 147 ATF_REQUIRE(errno == EAGAIN); 148 149 /* Don't block with O_NONBLOCK. */ 150 ATF_REQUIRE(fcntl(fd[1], F_SETFL, O_NONBLOCK) != -1); 151 ATF_REQUIRE(recv(fd[1], buf, maxdgram, 0) == -1); 152 ATF_REQUIRE(errno == EAGAIN); 153 154 /* Fail with ENOBUFS on full socket. */ 155 fill(fd[0], buf, maxdgram); 156 ATF_REQUIRE(send(fd[0], buf, maxdgram, 0) == -1); 157 ATF_REQUIRE(errno == ENOBUFS); 158 159 /* Fail with EAGAIN with O_NONBLOCK set. */ 160 ATF_REQUIRE(fcntl(fd[0], F_SETFL, O_NONBLOCK) != -1); 161 ATF_REQUIRE(send(fd[0], buf, maxdgram, 0) == -1); 162 ATF_REQUIRE(errno == EAGAIN); 163 164 /* Remote side closed -> ECONNRESET. */ 165 close(fd[1]); 166 ATF_REQUIRE(send(fd[0], buf, maxdgram, 0) == -1); 167 ATF_REQUIRE(errno == ECONNRESET); 168 } 169 170 ATF_TC_WITHOUT_HEAD(one2many); 171 ATF_TC_BODY(one2many, tc) 172 { 173 int one, many[3], two; 174 #define BUFSIZE 1024 175 char buf[BUFSIZE], goodboy[BUFSIZE], flooder[BUFSIZE], notconn[BUFSIZE]; 176 177 /* Establish one to many connection. */ 178 ATF_REQUIRE((one = socket(PF_UNIX, SOCK_DGRAM, 0)) > 0); 179 ATF_REQUIRE(bind(one, (struct sockaddr *)&sun, sizeof(sun)) == 0); 180 /* listen(2) shall fail. */ 181 ATF_REQUIRE(listen(one, -1) != 0); 182 for (int i = 0; i < 3; i++) { 183 ATF_REQUIRE((many[i] = socket(PF_UNIX, SOCK_DGRAM, 0)) > 0); 184 ATF_REQUIRE(connect(many[i], (struct sockaddr *)&sun, 185 sizeof(sun)) == 0); 186 } 187 188 /* accept() on UNIX/DGRAM is invalid. */ 189 ATF_REQUIRE(accept(one, NULL, NULL) == -1); 190 ATF_REQUIRE(errno == EINVAL); 191 192 /* 193 * Connecting a bound socket to self: a strange, useless, but 194 * historically existing edge case that is not explicitly described 195 * in SuS, neither is forbidden there. Works on FreeBSD and Linux. 196 */ 197 ATF_REQUIRE(connect(one, (struct sockaddr *)&sun, sizeof(sun)) == 0); 198 ATF_REQUIRE(send(one, buf, 42, 0) == 42); 199 ATF_REQUIRE(recv(one, buf, sizeof(buf), 0) == 42); 200 201 /* 202 * Interaction between concurrent senders. New feature in FreeBSD 14. 203 * 204 * One sender can not fill the receive side. Other senders can 205 * continue operation. Senders who don't fill their buffers are 206 * prioritized over flooders. Connected senders are prioritized over 207 * unconnected. 208 * 209 * Disconnecting a sender that has queued data optionally preserves 210 * the data. Allow the data to migrate to peers buffer only if the 211 * latter is empty. Otherwise discard it, to prevent against 212 * connect-fill-close attack. 213 */ 214 #define FLOODER 13 /* for connected flooder on many[0] */ 215 #define GOODBOY 42 /* for a good boy on many[1] */ 216 #define NOTCONN 66 /* for sendto(2) via two */ 217 goodboy[0] = GOODBOY; 218 flooder[0] = FLOODER; 219 notconn[0] = NOTCONN; 220 221 /* Connected priority over sendto(2). */ 222 ATF_REQUIRE((two = socket(PF_UNIX, SOCK_DGRAM, 0)) > 0); 223 ATF_REQUIRE(sendto(two, notconn, BUFSIZE, 0, (struct sockaddr *)&sun, 224 sizeof(sun)) == BUFSIZE); 225 ATF_REQUIRE(send(many[1], goodboy, BUFSIZE, 0) == BUFSIZE); 226 ATF_REQUIRE(recv(one, buf, sizeof(buf), 0) == sizeof(buf)); 227 ATF_REQUIRE(buf[0] == GOODBOY); /* message from good boy comes first */ 228 ATF_REQUIRE(recv(one, buf, sizeof(buf), 0) == sizeof(buf)); 229 ATF_REQUIRE(buf[0] == NOTCONN); /* only then message from sendto(2) */ 230 231 /* Casual sender priority over a flooder. */ 232 fill(many[0], flooder, sizeof(flooder)); 233 ATF_REQUIRE(send(many[0], flooder, BUFSIZE, 0) == -1); 234 ATF_REQUIRE(errno == ENOBUFS); 235 ATF_REQUIRE(send(many[1], goodboy, BUFSIZE, 0) == BUFSIZE); 236 ATF_REQUIRE(recv(one, buf, sizeof(buf), 0) == sizeof(buf)); 237 ATF_REQUIRE(buf[0] == GOODBOY); /* message from good boy comes first */ 238 ATF_REQUIRE(recv(one, buf, sizeof(buf), 0) == sizeof(buf)); 239 ATF_REQUIRE(buf[0] == FLOODER); /* only then message from flooder */ 240 241 /* Once seen, a message can't be deprioritized by any other message. */ 242 ATF_REQUIRE(recv(one, buf, sizeof(buf), MSG_PEEK) == sizeof(buf)); 243 ATF_REQUIRE(buf[0] == FLOODER); /* message from the flooder seen */ 244 ATF_REQUIRE(send(many[1], goodboy, BUFSIZE, 0) == BUFSIZE); 245 ATF_REQUIRE(recv(one, buf, sizeof(buf), MSG_PEEK) == sizeof(buf)); 246 ATF_REQUIRE(buf[0] == FLOODER); /* should be the same message */ 247 ATF_REQUIRE(recv(one, buf, sizeof(buf), 0) == sizeof(buf)); 248 ATF_REQUIRE(buf[0] == FLOODER); /* now we read it out... */ 249 ATF_REQUIRE(recv(one, buf, sizeof(buf), 0) == sizeof(buf)); 250 ATF_REQUIRE(buf[0] == GOODBOY); /* ... and next one is the good boy */ 251 252 /* Disconnect in presence of data from not connected. */ 253 ATF_REQUIRE(sendto(two, notconn, BUFSIZE, 0, (struct sockaddr *)&sun, 254 sizeof(sun)) == BUFSIZE); 255 close(many[0]); 256 ATF_REQUIRE(recv(one, buf, sizeof(buf), 0) == sizeof(buf)); 257 ATF_REQUIRE(buf[0] == NOTCONN); /* message from sendto() */ 258 ATF_REQUIRE(recv(one, buf, sizeof(buf), MSG_DONTWAIT) == -1); 259 ATF_REQUIRE(errno == EAGAIN); /* data from many[0] discarded */ 260 261 /* Disconnect in absence of data from not connected. */ 262 ATF_REQUIRE(send(many[1], goodboy, BUFSIZE, 0) == BUFSIZE); 263 close(many[1]); 264 ATF_REQUIRE(recv(one, buf, sizeof(buf), 0) == sizeof(buf)); 265 ATF_REQUIRE(buf[0] == GOODBOY); /* message from many[1] preserved */ 266 267 /* Check that nothing leaks on close(2). */ 268 ATF_REQUIRE(send(many[2], buf, 42, 0) == 42); 269 ATF_REQUIRE(send(many[2], buf, 42, 0) == 42); 270 ATF_REQUIRE(recv(one, buf, sizeof(buf), MSG_PEEK) == 42); 271 ATF_REQUIRE(sendto(two, notconn, 42, 0, (struct sockaddr *)&sun, 272 sizeof(sun)) == 42); 273 close(one); 274 } 275 276 /* 277 * Check that various mechanism report socket as readable and having 278 * 42 bytes of data. 279 */ 280 static void 281 test42(int fd) 282 { 283 284 /* ioctl(FIONREAD) */ 285 int data; 286 287 ATF_REQUIRE(ioctl(fd, FIONREAD, &data) != -1); 288 ATF_REQUIRE(data == 42); 289 290 /* select(2) */ 291 fd_set rfds; 292 293 FD_ZERO(&rfds); 294 FD_SET(fd, &rfds); 295 ATF_REQUIRE(select(fd + 1, &rfds, NULL, NULL, NULL) == 1); 296 ATF_REQUIRE(FD_ISSET(fd, &rfds)); 297 298 /* kevent(2) */ 299 struct kevent ev; 300 int kq; 301 302 ATF_REQUIRE((kq = kqueue()) != -1); 303 EV_SET(&ev, fd, EVFILT_READ, EV_ADD, NOTE_LOWAT, 41, NULL); 304 ATF_REQUIRE(kevent(kq, &ev, 1, NULL, 0, NULL) == 0); 305 ATF_REQUIRE(kevent(kq, NULL, 0, &ev, 1, NULL) == 1); 306 ATF_REQUIRE(ev.filter == EVFILT_READ); 307 ATF_REQUIRE(ev.data == 42); 308 309 /* aio(4) */ 310 char buf[50]; 311 struct aiocb aio = { 312 .aio_nbytes = 50, 313 .aio_fildes = fd, 314 .aio_buf = buf, 315 }, *aiop; 316 317 ATF_REQUIRE(aio_read(&aio) == 0); 318 ATF_REQUIRE(aio_waitcomplete(&aiop, NULL) == 42); 319 ATF_REQUIRE(aiop == &aio); 320 } 321 322 /* 323 * Send data and control in connected & unconnected mode and check that 324 * various event mechanisms see the data, but don't count control bytes. 325 */ 326 ATF_TC_WITHOUT_HEAD(event); 327 ATF_TC_BODY(event, tc) 328 { 329 int fd[2]; 330 char buf[50]; 331 struct iovec iov = { 332 .iov_base = buf, 333 .iov_len = 42, 334 }; 335 struct cmsghdr cmsg = { 336 .cmsg_len = CMSG_LEN(0), 337 .cmsg_level = SOL_SOCKET, 338 .cmsg_type = SCM_TIMESTAMP, 339 }; 340 struct msghdr msghdr = { 341 .msg_iov = &iov, 342 .msg_iovlen = 1, 343 .msg_control = &cmsg, 344 .msg_controllen = CMSG_LEN(0), 345 }; 346 347 /* Connected socket */ 348 ATF_REQUIRE(socketpair(PF_UNIX, SOCK_DGRAM, 0, fd) != -1); 349 ATF_REQUIRE(sendmsg(fd[0], &msghdr, 0) == 42); 350 test42(fd[1]); 351 close(fd[0]); 352 close(fd[1]); 353 354 /* Not-connected send */ 355 ATF_REQUIRE((fd[0] = socket(PF_UNIX, SOCK_DGRAM, 0)) > 0); 356 ATF_REQUIRE((fd[1] = socket(PF_UNIX, SOCK_DGRAM, 0)) > 0); 357 ATF_REQUIRE(bind(fd[0], (struct sockaddr *)&sun, sizeof(sun)) == 0); 358 ATF_REQUIRE(sendto(fd[1], buf, 42, 0, (struct sockaddr *)&sun, 359 sizeof(sun)) == 42); 360 test42(fd[0]); 361 } 362 363 ATF_TP_ADD_TCS(tp) 364 { 365 366 ATF_TP_ADD_TC(tp, basic); 367 ATF_TP_ADD_TC(tp, one2many); 368 ATF_TP_ADD_TC(tp, event); 369 370 return (atf_no_error()); 371 } 372