1 /* 2 * QEMU low level functions 3 * 4 * Copyright (c) 2003 Fabrice Bellard 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a copy 7 * of this software and associated documentation files (the "Software"), to deal 8 * in the Software without restriction, including without limitation the rights 9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 10 * copies of the Software, and to permit persons to whom the Software is 11 * furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be included in 14 * all copies or substantial portions of the Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 22 * THE SOFTWARE. 23 */ 24 #include <stdlib.h> 25 #include <stdio.h> 26 #include <stdarg.h> 27 #include <stdbool.h> 28 #include <string.h> 29 #include <errno.h> 30 #include <unistd.h> 31 #include <fcntl.h> 32 33 #ifndef _WIN32 34 #include <sys/socket.h> 35 #endif 36 37 /* Needed early for CONFIG_BSD etc. */ 38 #include "config-host.h" 39 40 #if defined(CONFIG_MADVISE) || defined(CONFIG_POSIX_MADVISE) 41 #include <sys/mman.h> 42 #endif 43 44 #ifdef CONFIG_SOLARIS 45 #include <sys/types.h> 46 #include <sys/statvfs.h> 47 /* See MySQL bug #7156 (http://bugs.mysql.com/bug.php?id=7156) for 48 discussion about Solaris header problems */ 49 extern int madvise(caddr_t, size_t, int); 50 #endif 51 52 #include "qemu-common.h" 53 #include "trace.h" 54 #include "qemu/sockets.h" 55 #include "monitor/monitor.h" 56 57 static bool fips_enabled = false; 58 59 static const char *qemu_version = QEMU_VERSION; 60 61 #ifndef CONFIG_ANDROID // See android/sockets.c instead. 62 int socket_set_cork(int fd, int v) 63 { 64 #if defined(SOL_TCP) && defined(TCP_CORK) 65 return qemu_setsockopt(fd, SOL_TCP, TCP_CORK, &v, sizeof(v)); 66 #else 67 return 0; 68 #endif 69 } 70 71 int socket_set_nodelay(int fd) 72 { 73 int v = 1; 74 return qemu_setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &v, sizeof(v)); 75 } 76 #endif // !CONFIG_ANDROID 77 78 int qemu_madvise(void *addr, size_t len, int advice) 79 { 80 if (advice == QEMU_MADV_INVALID) { 81 errno = EINVAL; 82 return -1; 83 } 84 #if defined(CONFIG_MADVISE) 85 return madvise(addr, len, advice); 86 #elif defined(CONFIG_POSIX_MADVISE) 87 return posix_madvise(addr, len, advice); 88 #else 89 errno = EINVAL; 90 return -1; 91 #endif 92 } 93 94 #ifndef CONFIG_ANDROID 95 #ifndef _WIN32 96 /* 97 * Dups an fd and sets the flags 98 */ 99 static int qemu_dup_flags(int fd, int flags) 100 { 101 int ret; 102 int serrno; 103 int dup_flags; 104 105 #ifdef F_DUPFD_CLOEXEC 106 ret = fcntl(fd, F_DUPFD_CLOEXEC, 0); 107 #else 108 ret = dup(fd); 109 if (ret != -1) { 110 qemu_set_cloexec(ret); 111 } 112 #endif 113 if (ret == -1) { 114 goto fail; 115 } 116 117 dup_flags = fcntl(ret, F_GETFL); 118 if (dup_flags == -1) { 119 goto fail; 120 } 121 122 if ((flags & O_SYNC) != (dup_flags & O_SYNC)) { 123 errno = EINVAL; 124 goto fail; 125 } 126 127 /* Set/unset flags that we can with fcntl */ 128 if (fcntl(ret, F_SETFL, flags) == -1) { 129 goto fail; 130 } 131 132 /* Truncate the file in the cases that open() would truncate it */ 133 if (flags & O_TRUNC || 134 ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))) { 135 if (ftruncate(ret, 0) == -1) { 136 goto fail; 137 } 138 } 139 140 return ret; 141 142 fail: 143 serrno = errno; 144 if (ret != -1) { 145 close(ret); 146 } 147 errno = serrno; 148 return -1; 149 } 150 151 static int qemu_parse_fdset(const char *param) 152 { 153 return qemu_parse_fd(param); 154 } 155 #endif 156 #endif // !CONFIG_ANDROID 157 158 /* 159 * Opens a file with FD_CLOEXEC set 160 */ 161 int qemu_open(const char *name, int flags, ...) 162 { 163 int ret; 164 int mode = 0; 165 166 #ifndef CONFIG_ANDROID 167 #ifndef _WIN32 168 const char *fdset_id_str; 169 170 /* Attempt dup of fd from fd set */ 171 if (strstart(name, "/dev/fdset/", &fdset_id_str)) { 172 int64_t fdset_id; 173 int fd, dupfd; 174 175 fdset_id = qemu_parse_fdset(fdset_id_str); 176 if (fdset_id == -1) { 177 errno = EINVAL; 178 return -1; 179 } 180 181 fd = monitor_fdset_get_fd(fdset_id, flags); 182 if (fd == -1) { 183 return -1; 184 } 185 186 dupfd = qemu_dup_flags(fd, flags); 187 if (dupfd == -1) { 188 return -1; 189 } 190 191 ret = monitor_fdset_dup_fd_add(fdset_id, dupfd); 192 if (ret == -1) { 193 close(dupfd); 194 errno = EINVAL; 195 return -1; 196 } 197 return dupfd; 198 } 199 #endif 200 #endif // !CONFIG_ANDROID 201 202 if (flags & O_CREAT) { 203 va_list ap; 204 205 va_start(ap, flags); 206 mode = va_arg(ap, int); 207 va_end(ap); 208 } 209 210 #ifdef O_CLOEXEC 211 ret = open(name, flags | O_CLOEXEC, mode); 212 #else 213 ret = open(name, flags, mode); 214 if (ret >= 0) { 215 qemu_set_cloexec(ret); 216 } 217 #endif 218 219 #ifdef O_DIRECT 220 if (ret == -1 && errno == EINVAL && (flags & O_DIRECT)) { 221 error_report("file system may not support O_DIRECT"); 222 errno = EINVAL; /* in case it was clobbered */ 223 } 224 #endif /* O_DIRECT */ 225 226 return ret; 227 } 228 229 int qemu_close(int fd) 230 { 231 #ifndef CONFIG_ANDROID 232 int64_t fdset_id; 233 234 /* Close fd that was dup'd from an fdset */ 235 fdset_id = monitor_fdset_dup_fd_find(fd); 236 if (fdset_id != -1) { 237 int ret; 238 239 ret = close(fd); 240 if (ret == 0) { 241 monitor_fdset_dup_fd_remove(fd); 242 } 243 244 return ret; 245 } 246 #endif 247 return close(fd); 248 } 249 250 /* 251 * A variant of write(2) which handles partial write. 252 * 253 * Return the number of bytes transferred. 254 * Set errno if fewer than `count' bytes are written. 255 * 256 * This function don't work with non-blocking fd's. 257 * Any of the possibilities with non-bloking fd's is bad: 258 * - return a short write (then name is wrong) 259 * - busy wait adding (errno == EAGAIN) to the loop 260 */ 261 ssize_t qemu_write_full(int fd, const void *buf, size_t count) 262 { 263 ssize_t ret = 0; 264 ssize_t total = 0; 265 266 while (count) { 267 ret = write(fd, buf, count); 268 if (ret < 0) { 269 if (errno == EINTR) 270 continue; 271 break; 272 } 273 274 count -= ret; 275 buf += ret; 276 total += ret; 277 } 278 279 return total; 280 } 281 282 /* 283 * Opens a socket with FD_CLOEXEC set 284 */ 285 int qemu_socket(int domain, int type, int protocol) 286 { 287 int ret; 288 289 #ifdef SOCK_CLOEXEC 290 ret = socket(domain, type | SOCK_CLOEXEC, protocol); 291 if (ret != -1 || errno != EINVAL) { 292 return ret; 293 } 294 #endif 295 ret = socket(domain, type, protocol); 296 if (ret >= 0) { 297 qemu_set_cloexec(ret); 298 } 299 300 return ret; 301 } 302 303 #ifndef CONFIG_ANDROID 304 /* 305 * Accept a connection and set FD_CLOEXEC 306 */ 307 int qemu_accept(int s, struct sockaddr *addr, socklen_t *addrlen) 308 { 309 int ret; 310 311 #ifdef CONFIG_ACCEPT4 312 ret = accept4(s, addr, addrlen, SOCK_CLOEXEC); 313 if (ret != -1 || errno != ENOSYS) { 314 return ret; 315 } 316 #endif 317 ret = accept(s, addr, addrlen); 318 if (ret >= 0) { 319 qemu_set_cloexec(ret); 320 } 321 322 return ret; 323 } 324 #endif 325 326 /* 327 * A variant of send(2) which handles partial write. 328 * 329 * Return the number of bytes transferred, which is only 330 * smaller than `count' if there is an error. 331 * 332 * This function won't work with non-blocking fd's. 333 * Any of the possibilities with non-bloking fd's is bad: 334 * - return a short write (then name is wrong) 335 * - busy wait adding (errno == EAGAIN) to the loop 336 */ 337 ssize_t qemu_send_full(int fd, const void *buf, size_t count, int flags) 338 { 339 ssize_t ret = 0; 340 ssize_t total = 0; 341 342 while (count) { 343 ret = send(fd, buf, count, flags); 344 if (ret < 0) { 345 if (errno == EINTR) { 346 continue; 347 } 348 break; 349 } 350 351 count -= ret; 352 buf += ret; 353 total += ret; 354 } 355 356 return total; 357 } 358 359 /* 360 * A variant of recv(2) which handles partial write. 361 * 362 * Return the number of bytes transferred, which is only 363 * smaller than `count' if there is an error. 364 * 365 * This function won't work with non-blocking fd's. 366 * Any of the possibilities with non-bloking fd's is bad: 367 * - return a short write (then name is wrong) 368 * - busy wait adding (errno == EAGAIN) to the loop 369 */ 370 ssize_t qemu_recv_full(int fd, void *buf, size_t count, int flags) 371 { 372 ssize_t ret = 0; 373 ssize_t total = 0; 374 375 while (count) { 376 ret = qemu_recv(fd, buf, count, flags); 377 if (ret <= 0) { 378 if (ret < 0 && errno == EINTR) { 379 continue; 380 } 381 break; 382 } 383 384 count -= ret; 385 buf += ret; 386 total += ret; 387 } 388 389 return total; 390 } 391 392 void qemu_set_version(const char *version) 393 { 394 qemu_version = version; 395 } 396 397 const char *qemu_get_version(void) 398 { 399 return qemu_version; 400 } 401 402 void fips_set_state(bool requested) 403 { 404 #ifdef __linux__ 405 if (requested) { 406 FILE *fds = fopen("/proc/sys/crypto/fips_enabled", "r"); 407 if (fds != NULL) { 408 fips_enabled = (fgetc(fds) == '1'); 409 fclose(fds); 410 } 411 } 412 #else 413 fips_enabled = false; 414 #endif /* __linux__ */ 415 416 #ifdef _FIPS_DEBUG 417 fprintf(stderr, "FIPS mode %s (requested %s)\n", 418 (fips_enabled ? "enabled" : "disabled"), 419 (requested ? "enabled" : "disabled")); 420 #endif 421 } 422 423 bool fips_get_state(void) 424 { 425 return fips_enabled; 426 } 427 428 #ifndef CONFIG_ANDROID 429 #ifdef _WIN32 430 static void socket_cleanup(void) 431 { 432 WSACleanup(); 433 } 434 #endif 435 436 int socket_init(void) 437 { 438 #ifdef _WIN32 439 WSADATA Data; 440 int ret, err; 441 442 ret = WSAStartup(MAKEWORD(2, 2), &Data); 443 if (ret != 0) { 444 err = WSAGetLastError(); 445 fprintf(stderr, "WSAStartup: %d\n", err); 446 return -1; 447 } 448 atexit(socket_cleanup); 449 #endif 450 return 0; 451 } 452 #endif // !CONFIG_ANDROID 453 454 #ifndef CONFIG_IOVEC 455 /* helper function for iov_send_recv() */ 456 static ssize_t 457 readv_writev(int fd, const struct iovec *iov, int iov_cnt, bool do_write) 458 { 459 unsigned i = 0; 460 ssize_t ret = 0; 461 while (i < iov_cnt) { 462 ssize_t r = do_write 463 ? write(fd, iov[i].iov_base, iov[i].iov_len) 464 : read(fd, iov[i].iov_base, iov[i].iov_len); 465 if (r > 0) { 466 ret += r; 467 } else if (!r) { 468 break; 469 } else if (errno == EINTR) { 470 continue; 471 } else { 472 /* else it is some "other" error, 473 * only return if there was no data processed. */ 474 if (ret == 0) { 475 ret = -1; 476 } 477 break; 478 } 479 i++; 480 } 481 return ret; 482 } 483 484 ssize_t 485 readv(int fd, const struct iovec *iov, int iov_cnt) 486 { 487 return readv_writev(fd, iov, iov_cnt, false); 488 } 489 490 ssize_t 491 writev(int fd, const struct iovec *iov, int iov_cnt) 492 { 493 return readv_writev(fd, iov, iov_cnt, true); 494 } 495 #endif 496 497 #if defined(_WIN32) && !QEMU_GNUC_PREREQ(4,4) 498 // Older Mingw32 didn't provide these. 499 int asprintf( char **, const char *, ... ); 500 int vasprintf( char **, const char *, va_list ); 501 502 int vasprintf( char **sptr, const char *fmt, va_list argv ) 503 { 504 int wanted = vsnprintf( *sptr = NULL, 0, fmt, argv ); 505 if( (wanted > 0) && ((*sptr = malloc( 1 + wanted )) != NULL) ) 506 return vsprintf( *sptr, fmt, argv ); 507 508 return wanted; 509 } 510 511 int asprintf( char **sptr, const char *fmt, ... ) 512 { 513 int retval; 514 va_list argv; 515 va_start( argv, fmt ); 516 retval = vasprintf( sptr, fmt, argv ); 517 va_end( argv ); 518 return retval; 519 } 520 #endif // _WIN32 && !QEMU_GNUC_PREREQ(4,4) 521