1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) 4 */ 5 6 #include <stdio.h> 7 #include <unistd.h> 8 #include <errno.h> 9 #include <fcntl.h> 10 #include <signal.h> 11 #include <sys/ioctl.h> 12 #include <sys/mount.h> 13 #include <sys/socket.h> 14 #include <sys/stat.h> 15 #include <sys/sysmacros.h> 16 #include <sys/un.h> 17 #include <sys/types.h> 18 #include <sys/eventfd.h> 19 #include <os.h> 20 21 static void copy_stat(struct uml_stat *dst, const struct stat64 *src) 22 { 23 *dst = ((struct uml_stat) { 24 .ust_dev = src->st_dev, /* device */ 25 .ust_ino = src->st_ino, /* inode */ 26 .ust_mode = src->st_mode, /* protection */ 27 .ust_nlink = src->st_nlink, /* number of hard links */ 28 .ust_uid = src->st_uid, /* user ID of owner */ 29 .ust_gid = src->st_gid, /* group ID of owner */ 30 .ust_size = src->st_size, /* total size, in bytes */ 31 .ust_blksize = src->st_blksize, /* blocksize for filesys I/O */ 32 .ust_blocks = src->st_blocks, /* number of blocks allocated */ 33 .ust_atime = src->st_atime, /* time of last access */ 34 .ust_mtime = src->st_mtime, /* time of last modification */ 35 .ust_ctime = src->st_ctime, /* time of last change */ 36 }); 37 } 38 39 int os_stat_fd(const int fd, struct uml_stat *ubuf) 40 { 41 struct stat64 sbuf; 42 int err; 43 44 CATCH_EINTR(err = fstat64(fd, &sbuf)); 45 if (err < 0) 46 return -errno; 47 48 if (ubuf != NULL) 49 copy_stat(ubuf, &sbuf); 50 return err; 51 } 52 53 int os_stat_file(const char *file_name, struct uml_stat *ubuf) 54 { 55 struct stat64 sbuf; 56 int err; 57 58 CATCH_EINTR(err = stat64(file_name, &sbuf)); 59 if (err < 0) 60 return -errno; 61 62 if (ubuf != NULL) 63 copy_stat(ubuf, &sbuf); 64 return err; 65 } 66 67 int os_access(const char *file, int mode) 68 { 69 int amode, err; 70 71 amode = (mode & OS_ACC_R_OK ? R_OK : 0) | 72 (mode & OS_ACC_W_OK ? W_OK : 0) | 73 (mode & OS_ACC_X_OK ? X_OK : 0) | 74 (mode & OS_ACC_F_OK ? F_OK : 0); 75 76 err = access(file, amode); 77 if (err < 0) 78 return -errno; 79 80 return 0; 81 } 82 83 /* FIXME? required only by hostaudio (because it passes ioctls verbatim) */ 84 int os_ioctl_generic(int fd, unsigned int cmd, unsigned long arg) 85 { 86 int err; 87 88 err = ioctl(fd, cmd, arg); 89 if (err < 0) 90 return -errno; 91 92 return err; 93 } 94 95 /* FIXME: ensure namebuf in os_get_if_name is big enough */ 96 int os_get_ifname(int fd, char* namebuf) 97 { 98 if (ioctl(fd, SIOCGIFNAME, namebuf) < 0) 99 return -errno; 100 101 return 0; 102 } 103 104 int os_set_slip(int fd) 105 { 106 int disc, sencap; 107 108 disc = N_SLIP; 109 if (ioctl(fd, TIOCSETD, &disc) < 0) 110 return -errno; 111 112 sencap = 0; 113 if (ioctl(fd, SIOCSIFENCAP, &sencap) < 0) 114 return -errno; 115 116 return 0; 117 } 118 119 int os_mode_fd(int fd, int mode) 120 { 121 int err; 122 123 CATCH_EINTR(err = fchmod(fd, mode)); 124 if (err < 0) 125 return -errno; 126 127 return 0; 128 } 129 130 int os_file_type(char *file) 131 { 132 struct uml_stat buf; 133 int err; 134 135 err = os_stat_file(file, &buf); 136 if (err < 0) 137 return err; 138 139 if (S_ISDIR(buf.ust_mode)) 140 return OS_TYPE_DIR; 141 else if (S_ISLNK(buf.ust_mode)) 142 return OS_TYPE_SYMLINK; 143 else if (S_ISCHR(buf.ust_mode)) 144 return OS_TYPE_CHARDEV; 145 else if (S_ISBLK(buf.ust_mode)) 146 return OS_TYPE_BLOCKDEV; 147 else if (S_ISFIFO(buf.ust_mode)) 148 return OS_TYPE_FIFO; 149 else if (S_ISSOCK(buf.ust_mode)) 150 return OS_TYPE_SOCK; 151 else return OS_TYPE_FILE; 152 } 153 154 int os_file_mode(const char *file, struct openflags *mode_out) 155 { 156 int err; 157 158 *mode_out = OPENFLAGS(); 159 160 err = access(file, W_OK); 161 if (err && (errno != EACCES)) 162 return -errno; 163 else if (!err) 164 *mode_out = of_write(*mode_out); 165 166 err = access(file, R_OK); 167 if (err && (errno != EACCES)) 168 return -errno; 169 else if (!err) 170 *mode_out = of_read(*mode_out); 171 172 return err; 173 } 174 175 int os_open_file(const char *file, struct openflags flags, int mode) 176 { 177 int fd, err, f = 0; 178 179 if (flags.r && flags.w) 180 f = O_RDWR; 181 else if (flags.r) 182 f = O_RDONLY; 183 else if (flags.w) 184 f = O_WRONLY; 185 else f = 0; 186 187 if (flags.s) 188 f |= O_SYNC; 189 if (flags.c) 190 f |= O_CREAT; 191 if (flags.t) 192 f |= O_TRUNC; 193 if (flags.e) 194 f |= O_EXCL; 195 if (flags.a) 196 f |= O_APPEND; 197 198 fd = open64(file, f, mode); 199 if (fd < 0) 200 return -errno; 201 202 if (flags.cl && fcntl(fd, F_SETFD, 1)) { 203 err = -errno; 204 close(fd); 205 return err; 206 } 207 208 return fd; 209 } 210 211 int os_connect_socket(const char *name) 212 { 213 struct sockaddr_un sock; 214 int fd, err; 215 216 sock.sun_family = AF_UNIX; 217 snprintf(sock.sun_path, sizeof(sock.sun_path), "%s", name); 218 219 fd = socket(AF_UNIX, SOCK_STREAM, 0); 220 if (fd < 0) { 221 err = -errno; 222 goto out; 223 } 224 225 err = connect(fd, (struct sockaddr *) &sock, sizeof(sock)); 226 if (err) { 227 err = -errno; 228 goto out_close; 229 } 230 231 return fd; 232 233 out_close: 234 close(fd); 235 out: 236 return err; 237 } 238 239 void os_close_file(int fd) 240 { 241 close(fd); 242 } 243 int os_fsync_file(int fd) 244 { 245 if (fsync(fd) < 0) 246 return -errno; 247 return 0; 248 } 249 250 int os_seek_file(int fd, unsigned long long offset) 251 { 252 unsigned long long actual; 253 254 actual = lseek64(fd, offset, SEEK_SET); 255 if (actual != offset) 256 return -errno; 257 return 0; 258 } 259 260 int os_read_file(int fd, void *buf, int len) 261 { 262 int n = read(fd, buf, len); 263 264 if (n < 0) 265 return -errno; 266 return n; 267 } 268 269 int os_pread_file(int fd, void *buf, int len, unsigned long long offset) 270 { 271 int n = pread(fd, buf, len, offset); 272 273 if (n < 0) 274 return -errno; 275 return n; 276 } 277 278 int os_write_file(int fd, const void *buf, int len) 279 { 280 int n = write(fd, (void *) buf, len); 281 282 if (n < 0) 283 return -errno; 284 return n; 285 } 286 287 int os_sync_file(int fd) 288 { 289 int n = fsync(fd); 290 291 if (n < 0) 292 return -errno; 293 return n; 294 } 295 296 int os_pwrite_file(int fd, const void *buf, int len, unsigned long long offset) 297 { 298 int n = pwrite(fd, (void *) buf, len, offset); 299 300 if (n < 0) 301 return -errno; 302 return n; 303 } 304 305 306 int os_file_size(const char *file, unsigned long long *size_out) 307 { 308 struct uml_stat buf; 309 int err; 310 311 err = os_stat_file(file, &buf); 312 if (err < 0) { 313 printk(UM_KERN_ERR "Couldn't stat \"%s\" : err = %d\n", file, 314 -err); 315 return err; 316 } 317 318 if (S_ISBLK(buf.ust_mode)) { 319 int fd; 320 long blocks; 321 322 fd = open(file, O_RDONLY, 0); 323 if (fd < 0) { 324 err = -errno; 325 printk(UM_KERN_ERR "Couldn't open \"%s\", " 326 "errno = %d\n", file, errno); 327 return err; 328 } 329 if (ioctl(fd, BLKGETSIZE, &blocks) < 0) { 330 err = -errno; 331 printk(UM_KERN_ERR "Couldn't get the block size of " 332 "\"%s\", errno = %d\n", file, errno); 333 close(fd); 334 return err; 335 } 336 *size_out = ((long long) blocks) * 512; 337 close(fd); 338 } 339 else *size_out = buf.ust_size; 340 341 return 0; 342 } 343 344 int os_file_modtime(const char *file, unsigned long *modtime) 345 { 346 struct uml_stat buf; 347 int err; 348 349 err = os_stat_file(file, &buf); 350 if (err < 0) { 351 printk(UM_KERN_ERR "Couldn't stat \"%s\" : err = %d\n", file, 352 -err); 353 return err; 354 } 355 356 *modtime = buf.ust_mtime; 357 return 0; 358 } 359 360 int os_set_exec_close(int fd) 361 { 362 int err; 363 364 CATCH_EINTR(err = fcntl(fd, F_SETFD, FD_CLOEXEC)); 365 366 if (err < 0) 367 return -errno; 368 return err; 369 } 370 371 int os_pipe(int *fds, int stream, int close_on_exec) 372 { 373 int err, type = stream ? SOCK_STREAM : SOCK_DGRAM; 374 375 err = socketpair(AF_UNIX, type, 0, fds); 376 if (err < 0) 377 return -errno; 378 379 if (!close_on_exec) 380 return 0; 381 382 err = os_set_exec_close(fds[0]); 383 if (err < 0) 384 goto error; 385 386 err = os_set_exec_close(fds[1]); 387 if (err < 0) 388 goto error; 389 390 return 0; 391 392 error: 393 printk(UM_KERN_ERR "os_pipe : Setting FD_CLOEXEC failed, err = %d\n", 394 -err); 395 close(fds[1]); 396 close(fds[0]); 397 return err; 398 } 399 400 int os_set_fd_async(int fd) 401 { 402 int err, flags; 403 404 flags = fcntl(fd, F_GETFL); 405 if (flags < 0) 406 return -errno; 407 408 flags |= O_ASYNC | O_NONBLOCK; 409 if (fcntl(fd, F_SETFL, flags) < 0) { 410 err = -errno; 411 printk(UM_KERN_ERR "os_set_fd_async : failed to set O_ASYNC " 412 "and O_NONBLOCK on fd # %d, errno = %d\n", fd, errno); 413 return err; 414 } 415 416 if ((fcntl(fd, F_SETSIG, SIGIO) < 0) || 417 (fcntl(fd, F_SETOWN, os_getpid()) < 0)) { 418 err = -errno; 419 printk(UM_KERN_ERR "os_set_fd_async : Failed to fcntl F_SETOWN " 420 "(or F_SETSIG) fd %d, errno = %d\n", fd, errno); 421 return err; 422 } 423 424 return 0; 425 } 426 427 int os_clear_fd_async(int fd) 428 { 429 int flags; 430 431 flags = fcntl(fd, F_GETFL); 432 if (flags < 0) 433 return -errno; 434 435 flags &= ~(O_ASYNC | O_NONBLOCK); 436 if (fcntl(fd, F_SETFL, flags) < 0) 437 return -errno; 438 return 0; 439 } 440 441 int os_set_fd_block(int fd, int blocking) 442 { 443 int flags; 444 445 flags = fcntl(fd, F_GETFL); 446 if (flags < 0) 447 return -errno; 448 449 if (blocking) 450 flags &= ~O_NONBLOCK; 451 else 452 flags |= O_NONBLOCK; 453 454 if (fcntl(fd, F_SETFL, flags) < 0) 455 return -errno; 456 457 return 0; 458 } 459 460 int os_accept_connection(int fd) 461 { 462 int new; 463 464 new = accept(fd, NULL, 0); 465 if (new < 0) 466 return -errno; 467 return new; 468 } 469 470 #ifndef SHUT_RD 471 #define SHUT_RD 0 472 #endif 473 474 #ifndef SHUT_WR 475 #define SHUT_WR 1 476 #endif 477 478 #ifndef SHUT_RDWR 479 #define SHUT_RDWR 2 480 #endif 481 482 int os_shutdown_socket(int fd, int r, int w) 483 { 484 int what, err; 485 486 if (r && w) 487 what = SHUT_RDWR; 488 else if (r) 489 what = SHUT_RD; 490 else if (w) 491 what = SHUT_WR; 492 else 493 return -EINVAL; 494 495 err = shutdown(fd, what); 496 if (err < 0) 497 return -errno; 498 return 0; 499 } 500 501 int os_rcv_fd(int fd, int *helper_pid_out) 502 { 503 int new, n; 504 char buf[CMSG_SPACE(sizeof(new))]; 505 struct msghdr msg; 506 struct cmsghdr *cmsg; 507 struct iovec iov; 508 509 msg.msg_name = NULL; 510 msg.msg_namelen = 0; 511 iov = ((struct iovec) { .iov_base = helper_pid_out, 512 .iov_len = sizeof(*helper_pid_out) }); 513 msg.msg_iov = &iov; 514 msg.msg_iovlen = 1; 515 msg.msg_control = buf; 516 msg.msg_controllen = sizeof(buf); 517 msg.msg_flags = 0; 518 519 n = recvmsg(fd, &msg, 0); 520 if (n < 0) 521 return -errno; 522 else if (n != iov.iov_len) 523 *helper_pid_out = -1; 524 525 cmsg = CMSG_FIRSTHDR(&msg); 526 if (cmsg == NULL) { 527 printk(UM_KERN_ERR "rcv_fd didn't receive anything, " 528 "error = %d\n", errno); 529 return -1; 530 } 531 if ((cmsg->cmsg_level != SOL_SOCKET) || 532 (cmsg->cmsg_type != SCM_RIGHTS)) { 533 printk(UM_KERN_ERR "rcv_fd didn't receive a descriptor\n"); 534 return -1; 535 } 536 537 new = ((int *) CMSG_DATA(cmsg))[0]; 538 return new; 539 } 540 541 int os_create_unix_socket(const char *file, int len, int close_on_exec) 542 { 543 struct sockaddr_un addr; 544 int sock, err; 545 546 sock = socket(PF_UNIX, SOCK_DGRAM, 0); 547 if (sock < 0) 548 return -errno; 549 550 if (close_on_exec) { 551 err = os_set_exec_close(sock); 552 if (err < 0) 553 printk(UM_KERN_ERR "create_unix_socket : " 554 "close_on_exec failed, err = %d", -err); 555 } 556 557 addr.sun_family = AF_UNIX; 558 559 snprintf(addr.sun_path, len, "%s", file); 560 561 err = bind(sock, (struct sockaddr *) &addr, sizeof(addr)); 562 if (err < 0) 563 return -errno; 564 565 return sock; 566 } 567 568 void os_flush_stdout(void) 569 { 570 fflush(stdout); 571 } 572 573 int os_lock_file(int fd, int excl) 574 { 575 int type = excl ? F_WRLCK : F_RDLCK; 576 struct flock lock = ((struct flock) { .l_type = type, 577 .l_whence = SEEK_SET, 578 .l_start = 0, 579 .l_len = 0 } ); 580 int err, save; 581 582 err = fcntl(fd, F_SETLK, &lock); 583 if (!err) 584 goto out; 585 586 save = -errno; 587 err = fcntl(fd, F_GETLK, &lock); 588 if (err) { 589 err = -errno; 590 goto out; 591 } 592 593 printk(UM_KERN_ERR "F_SETLK failed, file already locked by pid %d\n", 594 lock.l_pid); 595 err = save; 596 out: 597 return err; 598 } 599 600 unsigned os_major(unsigned long long dev) 601 { 602 return major(dev); 603 } 604 605 unsigned os_minor(unsigned long long dev) 606 { 607 return minor(dev); 608 } 609 610 unsigned long long os_makedev(unsigned major, unsigned minor) 611 { 612 return makedev(major, minor); 613 } 614 615 int os_falloc_punch(int fd, unsigned long long offset, int len) 616 { 617 int n = fallocate(fd, FALLOC_FL_PUNCH_HOLE|FALLOC_FL_KEEP_SIZE, offset, len); 618 619 if (n < 0) 620 return -errno; 621 return n; 622 } 623 624 int os_eventfd(unsigned int initval, int flags) 625 { 626 int fd = eventfd(initval, flags); 627 628 if (fd < 0) 629 return -errno; 630 return fd; 631 } 632 633 int os_sendmsg_fds(int fd, const void *buf, unsigned int len, const int *fds, 634 unsigned int fds_num) 635 { 636 struct iovec iov = { 637 .iov_base = (void *) buf, 638 .iov_len = len, 639 }; 640 union { 641 char control[CMSG_SPACE(sizeof(*fds) * OS_SENDMSG_MAX_FDS)]; 642 struct cmsghdr align; 643 } u; 644 unsigned int fds_size = sizeof(*fds) * fds_num; 645 struct msghdr msg = { 646 .msg_iov = &iov, 647 .msg_iovlen = 1, 648 .msg_control = u.control, 649 .msg_controllen = CMSG_SPACE(fds_size), 650 }; 651 struct cmsghdr *cmsg = CMSG_FIRSTHDR(&msg); 652 int err; 653 654 if (fds_num > OS_SENDMSG_MAX_FDS) 655 return -EINVAL; 656 memset(u.control, 0, sizeof(u.control)); 657 cmsg->cmsg_level = SOL_SOCKET; 658 cmsg->cmsg_type = SCM_RIGHTS; 659 cmsg->cmsg_len = CMSG_LEN(fds_size); 660 memcpy(CMSG_DATA(cmsg), fds, fds_size); 661 err = sendmsg(fd, &msg, 0); 662 663 if (err < 0) 664 return -errno; 665 return err; 666 } 667