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 <linux/falloc.h> 12 #include <sys/ioctl.h> 13 #include <sys/mount.h> 14 #include <sys/socket.h> 15 #include <sys/stat.h> 16 #include <sys/sysmacros.h> 17 #include <sys/un.h> 18 #include <sys/types.h> 19 #include <sys/eventfd.h> 20 #include <os.h> 21 22 static void copy_stat(struct uml_stat *dst, const struct stat64 *src) 23 { 24 *dst = ((struct uml_stat) { 25 .ust_dev = src->st_dev, /* device */ 26 .ust_ino = src->st_ino, /* inode */ 27 .ust_mode = src->st_mode, /* protection */ 28 .ust_nlink = src->st_nlink, /* number of hard links */ 29 .ust_uid = src->st_uid, /* user ID of owner */ 30 .ust_gid = src->st_gid, /* group ID of owner */ 31 .ust_size = src->st_size, /* total size, in bytes */ 32 .ust_blksize = src->st_blksize, /* blocksize for filesys I/O */ 33 .ust_blocks = src->st_blocks, /* number of blocks allocated */ 34 .ust_atime = src->st_atime, /* time of last access */ 35 .ust_mtime = src->st_mtime, /* time of last modification */ 36 .ust_ctime = src->st_ctime, /* time of last change */ 37 }); 38 } 39 40 int os_stat_fd(const int fd, struct uml_stat *ubuf) 41 { 42 struct stat64 sbuf; 43 int err; 44 45 CATCH_EINTR(err = fstat64(fd, &sbuf)); 46 if (err < 0) 47 return -errno; 48 49 if (ubuf != NULL) 50 copy_stat(ubuf, &sbuf); 51 return err; 52 } 53 54 int os_stat_file(const char *file_name, struct uml_stat *ubuf) 55 { 56 struct stat64 sbuf; 57 int err; 58 59 CATCH_EINTR(err = stat64(file_name, &sbuf)); 60 if (err < 0) 61 return -errno; 62 63 if (ubuf != NULL) 64 copy_stat(ubuf, &sbuf); 65 return err; 66 } 67 68 int os_access(const char *file, int mode) 69 { 70 int amode, err; 71 72 amode = (mode & OS_ACC_R_OK ? R_OK : 0) | 73 (mode & OS_ACC_W_OK ? W_OK : 0) | 74 (mode & OS_ACC_X_OK ? X_OK : 0) | 75 (mode & OS_ACC_F_OK ? F_OK : 0); 76 77 err = access(file, amode); 78 if (err < 0) 79 return -errno; 80 81 return 0; 82 } 83 84 /* FIXME? required only by hostaudio (because it passes ioctls verbatim) */ 85 int os_ioctl_generic(int fd, unsigned int cmd, unsigned long arg) 86 { 87 int err; 88 89 err = ioctl(fd, cmd, arg); 90 if (err < 0) 91 return -errno; 92 93 return err; 94 } 95 96 /* FIXME: ensure namebuf in os_get_if_name is big enough */ 97 int os_get_ifname(int fd, char* namebuf) 98 { 99 if (ioctl(fd, SIOCGIFNAME, namebuf) < 0) 100 return -errno; 101 102 return 0; 103 } 104 105 int os_set_slip(int fd) 106 { 107 int disc, sencap; 108 109 disc = N_SLIP; 110 if (ioctl(fd, TIOCSETD, &disc) < 0) 111 return -errno; 112 113 sencap = 0; 114 if (ioctl(fd, SIOCSIFENCAP, &sencap) < 0) 115 return -errno; 116 117 return 0; 118 } 119 120 int os_mode_fd(int fd, int mode) 121 { 122 int err; 123 124 CATCH_EINTR(err = fchmod(fd, mode)); 125 if (err < 0) 126 return -errno; 127 128 return 0; 129 } 130 131 int os_file_type(char *file) 132 { 133 struct uml_stat buf; 134 int err; 135 136 err = os_stat_file(file, &buf); 137 if (err < 0) 138 return err; 139 140 if (S_ISDIR(buf.ust_mode)) 141 return OS_TYPE_DIR; 142 else if (S_ISLNK(buf.ust_mode)) 143 return OS_TYPE_SYMLINK; 144 else if (S_ISCHR(buf.ust_mode)) 145 return OS_TYPE_CHARDEV; 146 else if (S_ISBLK(buf.ust_mode)) 147 return OS_TYPE_BLOCKDEV; 148 else if (S_ISFIFO(buf.ust_mode)) 149 return OS_TYPE_FIFO; 150 else if (S_ISSOCK(buf.ust_mode)) 151 return OS_TYPE_SOCK; 152 else return OS_TYPE_FILE; 153 } 154 155 int os_file_mode(const char *file, struct openflags *mode_out) 156 { 157 int err; 158 159 *mode_out = OPENFLAGS(); 160 161 err = access(file, W_OK); 162 if (err && (errno != EACCES)) 163 return -errno; 164 else if (!err) 165 *mode_out = of_write(*mode_out); 166 167 err = access(file, R_OK); 168 if (err && (errno != EACCES)) 169 return -errno; 170 else if (!err) 171 *mode_out = of_read(*mode_out); 172 173 return err; 174 } 175 176 int os_open_file(const char *file, struct openflags flags, int mode) 177 { 178 int fd, err, f = 0; 179 180 if (flags.r && flags.w) 181 f = O_RDWR; 182 else if (flags.r) 183 f = O_RDONLY; 184 else if (flags.w) 185 f = O_WRONLY; 186 else f = 0; 187 188 if (flags.s) 189 f |= O_SYNC; 190 if (flags.c) 191 f |= O_CREAT; 192 if (flags.t) 193 f |= O_TRUNC; 194 if (flags.e) 195 f |= O_EXCL; 196 if (flags.a) 197 f |= O_APPEND; 198 199 fd = open64(file, f, mode); 200 if (fd < 0) 201 return -errno; 202 203 if (flags.cl && fcntl(fd, F_SETFD, 1)) { 204 err = -errno; 205 close(fd); 206 return err; 207 } 208 209 return fd; 210 } 211 212 int os_connect_socket(const char *name) 213 { 214 struct sockaddr_un sock; 215 int fd, err; 216 217 sock.sun_family = AF_UNIX; 218 snprintf(sock.sun_path, sizeof(sock.sun_path), "%s", name); 219 220 fd = socket(AF_UNIX, SOCK_STREAM, 0); 221 if (fd < 0) { 222 err = -errno; 223 goto out; 224 } 225 226 err = connect(fd, (struct sockaddr *) &sock, sizeof(sock)); 227 if (err) { 228 err = -errno; 229 goto out_close; 230 } 231 232 return fd; 233 234 out_close: 235 close(fd); 236 out: 237 return err; 238 } 239 240 void os_close_file(int fd) 241 { 242 close(fd); 243 } 244 int os_fsync_file(int fd) 245 { 246 if (fsync(fd) < 0) 247 return -errno; 248 return 0; 249 } 250 251 int os_seek_file(int fd, unsigned long long offset) 252 { 253 unsigned long long actual; 254 255 actual = lseek64(fd, offset, SEEK_SET); 256 if (actual != offset) 257 return -errno; 258 return 0; 259 } 260 261 int os_read_file(int fd, void *buf, int len) 262 { 263 int n = read(fd, buf, len); 264 265 if (n < 0) 266 return -errno; 267 return n; 268 } 269 270 int os_pread_file(int fd, void *buf, int len, unsigned long long offset) 271 { 272 int n = pread(fd, buf, len, offset); 273 274 if (n < 0) 275 return -errno; 276 return n; 277 } 278 279 int os_write_file(int fd, const void *buf, int len) 280 { 281 int n = write(fd, (void *) buf, len); 282 283 if (n < 0) 284 return -errno; 285 return n; 286 } 287 288 int os_sync_file(int fd) 289 { 290 int n = fsync(fd); 291 292 if (n < 0) 293 return -errno; 294 return n; 295 } 296 297 int os_pwrite_file(int fd, const void *buf, int len, unsigned long long offset) 298 { 299 int n = pwrite(fd, (void *) buf, len, offset); 300 301 if (n < 0) 302 return -errno; 303 return n; 304 } 305 306 307 int os_file_size(const char *file, unsigned long long *size_out) 308 { 309 struct uml_stat buf; 310 int err; 311 312 err = os_stat_file(file, &buf); 313 if (err < 0) { 314 printk(UM_KERN_ERR "Couldn't stat \"%s\" : err = %d\n", file, 315 -err); 316 return err; 317 } 318 319 if (S_ISBLK(buf.ust_mode)) { 320 int fd; 321 long blocks; 322 323 fd = open(file, O_RDONLY, 0); 324 if (fd < 0) { 325 err = -errno; 326 printk(UM_KERN_ERR "Couldn't open \"%s\", " 327 "errno = %d\n", file, errno); 328 return err; 329 } 330 if (ioctl(fd, BLKGETSIZE, &blocks) < 0) { 331 err = -errno; 332 printk(UM_KERN_ERR "Couldn't get the block size of " 333 "\"%s\", errno = %d\n", file, errno); 334 close(fd); 335 return err; 336 } 337 *size_out = ((long long) blocks) * 512; 338 close(fd); 339 } 340 else *size_out = buf.ust_size; 341 342 return 0; 343 } 344 345 int os_file_modtime(const char *file, long long *modtime) 346 { 347 struct uml_stat buf; 348 int err; 349 350 err = os_stat_file(file, &buf); 351 if (err < 0) { 352 printk(UM_KERN_ERR "Couldn't stat \"%s\" : err = %d\n", file, 353 -err); 354 return err; 355 } 356 357 *modtime = buf.ust_mtime; 358 return 0; 359 } 360 361 int os_set_exec_close(int fd) 362 { 363 int err; 364 365 CATCH_EINTR(err = fcntl(fd, F_SETFD, FD_CLOEXEC)); 366 367 if (err < 0) 368 return -errno; 369 return err; 370 } 371 372 int os_pipe(int *fds, int stream, int close_on_exec) 373 { 374 int err, type = stream ? SOCK_STREAM : SOCK_DGRAM; 375 376 err = socketpair(AF_UNIX, type, 0, fds); 377 if (err < 0) 378 return -errno; 379 380 if (!close_on_exec) 381 return 0; 382 383 err = os_set_exec_close(fds[0]); 384 if (err < 0) 385 goto error; 386 387 err = os_set_exec_close(fds[1]); 388 if (err < 0) 389 goto error; 390 391 return 0; 392 393 error: 394 printk(UM_KERN_ERR "os_pipe : Setting FD_CLOEXEC failed, err = %d\n", 395 -err); 396 close(fds[1]); 397 close(fds[0]); 398 return err; 399 } 400 401 int os_set_fd_async(int fd) 402 { 403 int err, flags; 404 405 flags = fcntl(fd, F_GETFL); 406 if (flags < 0) 407 return -errno; 408 409 flags |= O_ASYNC | O_NONBLOCK; 410 if (fcntl(fd, F_SETFL, flags) < 0) { 411 err = -errno; 412 printk(UM_KERN_ERR "os_set_fd_async : failed to set O_ASYNC " 413 "and O_NONBLOCK on fd # %d, errno = %d\n", fd, errno); 414 return err; 415 } 416 417 if ((fcntl(fd, F_SETSIG, SIGIO) < 0) || 418 (fcntl(fd, F_SETOWN, os_getpid()) < 0)) { 419 err = -errno; 420 printk(UM_KERN_ERR "os_set_fd_async : Failed to fcntl F_SETOWN " 421 "(or F_SETSIG) fd %d, errno = %d\n", fd, errno); 422 return err; 423 } 424 425 return 0; 426 } 427 428 int os_clear_fd_async(int fd) 429 { 430 int flags; 431 432 flags = fcntl(fd, F_GETFL); 433 if (flags < 0) 434 return -errno; 435 436 flags &= ~(O_ASYNC | O_NONBLOCK); 437 if (fcntl(fd, F_SETFL, flags) < 0) 438 return -errno; 439 return 0; 440 } 441 442 int os_set_fd_block(int fd, int blocking) 443 { 444 int flags; 445 446 flags = fcntl(fd, F_GETFL); 447 if (flags < 0) 448 return -errno; 449 450 if (blocking) 451 flags &= ~O_NONBLOCK; 452 else 453 flags |= O_NONBLOCK; 454 455 if (fcntl(fd, F_SETFL, flags) < 0) 456 return -errno; 457 458 return 0; 459 } 460 461 int os_accept_connection(int fd) 462 { 463 int new; 464 465 new = accept(fd, NULL, 0); 466 if (new < 0) 467 return -errno; 468 return new; 469 } 470 471 #ifndef SHUT_RD 472 #define SHUT_RD 0 473 #endif 474 475 #ifndef SHUT_WR 476 #define SHUT_WR 1 477 #endif 478 479 #ifndef SHUT_RDWR 480 #define SHUT_RDWR 2 481 #endif 482 483 int os_shutdown_socket(int fd, int r, int w) 484 { 485 int what, err; 486 487 if (r && w) 488 what = SHUT_RDWR; 489 else if (r) 490 what = SHUT_RD; 491 else if (w) 492 what = SHUT_WR; 493 else 494 return -EINVAL; 495 496 err = shutdown(fd, what); 497 if (err < 0) 498 return -errno; 499 return 0; 500 } 501 502 int os_rcv_fd(int fd, int *helper_pid_out) 503 { 504 int new, n; 505 char buf[CMSG_SPACE(sizeof(new))]; 506 struct msghdr msg; 507 struct cmsghdr *cmsg; 508 struct iovec iov; 509 510 msg.msg_name = NULL; 511 msg.msg_namelen = 0; 512 iov = ((struct iovec) { .iov_base = helper_pid_out, 513 .iov_len = sizeof(*helper_pid_out) }); 514 msg.msg_iov = &iov; 515 msg.msg_iovlen = 1; 516 msg.msg_control = buf; 517 msg.msg_controllen = sizeof(buf); 518 msg.msg_flags = 0; 519 520 n = recvmsg(fd, &msg, 0); 521 if (n < 0) 522 return -errno; 523 else if (n != iov.iov_len) 524 *helper_pid_out = -1; 525 526 cmsg = CMSG_FIRSTHDR(&msg); 527 if (cmsg == NULL) { 528 printk(UM_KERN_ERR "rcv_fd didn't receive anything, " 529 "error = %d\n", errno); 530 return -1; 531 } 532 if ((cmsg->cmsg_level != SOL_SOCKET) || 533 (cmsg->cmsg_type != SCM_RIGHTS)) { 534 printk(UM_KERN_ERR "rcv_fd didn't receive a descriptor\n"); 535 return -1; 536 } 537 538 new = ((int *) CMSG_DATA(cmsg))[0]; 539 return new; 540 } 541 542 int os_create_unix_socket(const char *file, int len, int close_on_exec) 543 { 544 struct sockaddr_un addr; 545 int sock, err; 546 547 sock = socket(PF_UNIX, SOCK_DGRAM, 0); 548 if (sock < 0) 549 return -errno; 550 551 if (close_on_exec) { 552 err = os_set_exec_close(sock); 553 if (err < 0) 554 printk(UM_KERN_ERR "create_unix_socket : " 555 "close_on_exec failed, err = %d", -err); 556 } 557 558 addr.sun_family = AF_UNIX; 559 560 snprintf(addr.sun_path, len, "%s", file); 561 562 err = bind(sock, (struct sockaddr *) &addr, sizeof(addr)); 563 if (err < 0) 564 return -errno; 565 566 return sock; 567 } 568 569 void os_flush_stdout(void) 570 { 571 fflush(stdout); 572 } 573 574 int os_lock_file(int fd, int excl) 575 { 576 int type = excl ? F_WRLCK : F_RDLCK; 577 struct flock lock = ((struct flock) { .l_type = type, 578 .l_whence = SEEK_SET, 579 .l_start = 0, 580 .l_len = 0 } ); 581 int err, save; 582 583 err = fcntl(fd, F_SETLK, &lock); 584 if (!err) 585 goto out; 586 587 save = -errno; 588 err = fcntl(fd, F_GETLK, &lock); 589 if (err) { 590 err = -errno; 591 goto out; 592 } 593 594 printk(UM_KERN_ERR "F_SETLK failed, file already locked by pid %d\n", 595 lock.l_pid); 596 err = save; 597 out: 598 return err; 599 } 600 601 unsigned os_major(unsigned long long dev) 602 { 603 return major(dev); 604 } 605 606 unsigned os_minor(unsigned long long dev) 607 { 608 return minor(dev); 609 } 610 611 unsigned long long os_makedev(unsigned major, unsigned minor) 612 { 613 return makedev(major, minor); 614 } 615 616 int os_falloc_punch(int fd, unsigned long long offset, int len) 617 { 618 int n = fallocate(fd, FALLOC_FL_PUNCH_HOLE|FALLOC_FL_KEEP_SIZE, offset, len); 619 620 if (n < 0) 621 return -errno; 622 return n; 623 } 624 625 int os_eventfd(unsigned int initval, int flags) 626 { 627 int fd = eventfd(initval, flags); 628 629 if (fd < 0) 630 return -errno; 631 return fd; 632 } 633 634 int os_sendmsg_fds(int fd, const void *buf, unsigned int len, const int *fds, 635 unsigned int fds_num) 636 { 637 struct iovec iov = { 638 .iov_base = (void *) buf, 639 .iov_len = len, 640 }; 641 union { 642 char control[CMSG_SPACE(sizeof(*fds) * OS_SENDMSG_MAX_FDS)]; 643 struct cmsghdr align; 644 } u; 645 unsigned int fds_size = sizeof(*fds) * fds_num; 646 struct msghdr msg = { 647 .msg_iov = &iov, 648 .msg_iovlen = 1, 649 .msg_control = u.control, 650 .msg_controllen = CMSG_SPACE(fds_size), 651 }; 652 struct cmsghdr *cmsg = CMSG_FIRSTHDR(&msg); 653 int err; 654 655 if (fds_num > OS_SENDMSG_MAX_FDS) 656 return -EINVAL; 657 memset(u.control, 0, sizeof(u.control)); 658 cmsg->cmsg_level = SOL_SOCKET; 659 cmsg->cmsg_type = SCM_RIGHTS; 660 cmsg->cmsg_len = CMSG_LEN(fds_size); 661 memcpy(CMSG_DATA(cmsg), fds, fds_size); 662 err = sendmsg(fd, &msg, 0); 663 664 if (err < 0) 665 return -errno; 666 return err; 667 } 668