1 /* 2 * 9p Posix callback 3 * 4 * Copyright IBM, Corp. 2010 5 * 6 * Authors: 7 * Anthony Liguori <aliguori@us.ibm.com> 8 * 9 * This work is licensed under the terms of the GNU GPL, version 2. See 10 * the COPYING file in the top-level directory. 11 * 12 */ 13 14 #include "qemu/osdep.h" 15 #include "9p.h" 16 #include "9p-local.h" 17 #include "9p-xattr.h" 18 #include "9p-util.h" 19 #include "fsdev/qemu-fsdev.h" /* local_ops */ 20 #include <arpa/inet.h> 21 #include <pwd.h> 22 #include <grp.h> 23 #include <sys/socket.h> 24 #include <sys/un.h> 25 #include "qemu/xattr.h" 26 #include "qemu/cutils.h" 27 #include "qemu/error-report.h" 28 #include <libgen.h> 29 #include <linux/fs.h> 30 #ifdef CONFIG_LINUX_MAGIC_H 31 #include <linux/magic.h> 32 #endif 33 #include <sys/ioctl.h> 34 35 #ifndef XFS_SUPER_MAGIC 36 #define XFS_SUPER_MAGIC 0x58465342 37 #endif 38 #ifndef EXT2_SUPER_MAGIC 39 #define EXT2_SUPER_MAGIC 0xEF53 40 #endif 41 #ifndef REISERFS_SUPER_MAGIC 42 #define REISERFS_SUPER_MAGIC 0x52654973 43 #endif 44 #ifndef BTRFS_SUPER_MAGIC 45 #define BTRFS_SUPER_MAGIC 0x9123683E 46 #endif 47 48 typedef struct { 49 int mountfd; 50 } LocalData; 51 52 int local_open_nofollow(FsContext *fs_ctx, const char *path, int flags, 53 mode_t mode) 54 { 55 LocalData *data = fs_ctx->private; 56 57 /* All paths are relative to the path data->mountfd points to */ 58 while (*path == '/') { 59 path++; 60 } 61 62 return relative_openat_nofollow(data->mountfd, path, flags, mode); 63 } 64 65 int local_opendir_nofollow(FsContext *fs_ctx, const char *path) 66 { 67 return local_open_nofollow(fs_ctx, path, O_DIRECTORY | O_RDONLY, 0); 68 } 69 70 static void renameat_preserve_errno(int odirfd, const char *opath, int ndirfd, 71 const char *npath) 72 { 73 int serrno = errno; 74 renameat(odirfd, opath, ndirfd, npath); 75 errno = serrno; 76 } 77 78 static void unlinkat_preserve_errno(int dirfd, const char *path, int flags) 79 { 80 int serrno = errno; 81 unlinkat(dirfd, path, flags); 82 errno = serrno; 83 } 84 85 #define VIRTFS_META_DIR ".virtfs_metadata" 86 87 static char *local_mapped_attr_path(FsContext *ctx, const char *path) 88 { 89 int dirlen; 90 const char *name = strrchr(path, '/'); 91 if (name) { 92 dirlen = name - path; 93 ++name; 94 } else { 95 name = path; 96 dirlen = 0; 97 } 98 return g_strdup_printf("%s/%.*s/%s/%s", ctx->fs_root, 99 dirlen, path, VIRTFS_META_DIR, name); 100 } 101 102 static FILE *local_fopen(const char *path, const char *mode) 103 { 104 int fd, o_mode = 0; 105 FILE *fp; 106 int flags = O_NOFOLLOW; 107 /* 108 * only supports two modes 109 */ 110 if (mode[0] == 'r') { 111 flags |= O_RDONLY; 112 } else if (mode[0] == 'w') { 113 flags |= O_WRONLY | O_TRUNC | O_CREAT; 114 o_mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH; 115 } else { 116 return NULL; 117 } 118 fd = open(path, flags, o_mode); 119 if (fd == -1) { 120 return NULL; 121 } 122 fp = fdopen(fd, mode); 123 if (!fp) { 124 close(fd); 125 } 126 return fp; 127 } 128 129 static FILE *local_fopenat(int dirfd, const char *name, const char *mode) 130 { 131 int fd, o_mode = 0; 132 FILE *fp; 133 int flags; 134 /* 135 * only supports two modes 136 */ 137 if (mode[0] == 'r') { 138 flags = O_RDONLY; 139 } else if (mode[0] == 'w') { 140 flags = O_WRONLY | O_TRUNC | O_CREAT; 141 o_mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH; 142 } else { 143 return NULL; 144 } 145 fd = openat_file(dirfd, name, flags, o_mode); 146 if (fd == -1) { 147 return NULL; 148 } 149 fp = fdopen(fd, mode); 150 if (!fp) { 151 close(fd); 152 } 153 return fp; 154 } 155 156 #define ATTR_MAX 100 157 static void local_mapped_file_attr(int dirfd, const char *name, 158 struct stat *stbuf) 159 { 160 FILE *fp; 161 char buf[ATTR_MAX]; 162 int map_dirfd; 163 164 map_dirfd = openat_dir(dirfd, VIRTFS_META_DIR); 165 if (map_dirfd == -1) { 166 return; 167 } 168 169 fp = local_fopenat(map_dirfd, name, "r"); 170 close_preserve_errno(map_dirfd); 171 if (!fp) { 172 return; 173 } 174 memset(buf, 0, ATTR_MAX); 175 while (fgets(buf, ATTR_MAX, fp)) { 176 if (!strncmp(buf, "virtfs.uid", 10)) { 177 stbuf->st_uid = atoi(buf+11); 178 } else if (!strncmp(buf, "virtfs.gid", 10)) { 179 stbuf->st_gid = atoi(buf+11); 180 } else if (!strncmp(buf, "virtfs.mode", 11)) { 181 stbuf->st_mode = atoi(buf+12); 182 } else if (!strncmp(buf, "virtfs.rdev", 11)) { 183 stbuf->st_rdev = atoi(buf+12); 184 } 185 memset(buf, 0, ATTR_MAX); 186 } 187 fclose(fp); 188 } 189 190 static int local_lstat(FsContext *fs_ctx, V9fsPath *fs_path, struct stat *stbuf) 191 { 192 int err = -1; 193 char *dirpath = g_path_get_dirname(fs_path->data); 194 char *name = g_path_get_basename(fs_path->data); 195 int dirfd; 196 197 dirfd = local_opendir_nofollow(fs_ctx, dirpath); 198 if (dirfd == -1) { 199 goto out; 200 } 201 202 err = fstatat(dirfd, name, stbuf, AT_SYMLINK_NOFOLLOW); 203 if (err) { 204 goto err_out; 205 } 206 if (fs_ctx->export_flags & V9FS_SM_MAPPED) { 207 /* Actual credentials are part of extended attrs */ 208 uid_t tmp_uid; 209 gid_t tmp_gid; 210 mode_t tmp_mode; 211 dev_t tmp_dev; 212 213 if (fgetxattrat_nofollow(dirfd, name, "user.virtfs.uid", &tmp_uid, 214 sizeof(uid_t)) > 0) { 215 stbuf->st_uid = le32_to_cpu(tmp_uid); 216 } 217 if (fgetxattrat_nofollow(dirfd, name, "user.virtfs.gid", &tmp_gid, 218 sizeof(gid_t)) > 0) { 219 stbuf->st_gid = le32_to_cpu(tmp_gid); 220 } 221 if (fgetxattrat_nofollow(dirfd, name, "user.virtfs.mode", &tmp_mode, 222 sizeof(mode_t)) > 0) { 223 stbuf->st_mode = le32_to_cpu(tmp_mode); 224 } 225 if (fgetxattrat_nofollow(dirfd, name, "user.virtfs.rdev", &tmp_dev, 226 sizeof(dev_t)) > 0) { 227 stbuf->st_rdev = le64_to_cpu(tmp_dev); 228 } 229 } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) { 230 local_mapped_file_attr(dirfd, name, stbuf); 231 } 232 233 err_out: 234 close_preserve_errno(dirfd); 235 out: 236 g_free(name); 237 g_free(dirpath); 238 return err; 239 } 240 241 static int local_create_mapped_attr_dir(FsContext *ctx, const char *path) 242 { 243 int err; 244 char *attr_dir; 245 char *tmp_path = g_strdup(path); 246 247 attr_dir = g_strdup_printf("%s/%s/%s", 248 ctx->fs_root, dirname(tmp_path), VIRTFS_META_DIR); 249 250 err = mkdir(attr_dir, 0700); 251 if (err < 0 && errno == EEXIST) { 252 err = 0; 253 } 254 g_free(attr_dir); 255 g_free(tmp_path); 256 return err; 257 } 258 259 static int local_set_mapped_file_attr(FsContext *ctx, 260 const char *path, FsCred *credp) 261 { 262 FILE *fp; 263 int ret = 0; 264 char buf[ATTR_MAX]; 265 char *attr_path; 266 int uid = -1, gid = -1, mode = -1, rdev = -1; 267 268 attr_path = local_mapped_attr_path(ctx, path); 269 fp = local_fopen(attr_path, "r"); 270 if (!fp) { 271 goto create_map_file; 272 } 273 memset(buf, 0, ATTR_MAX); 274 while (fgets(buf, ATTR_MAX, fp)) { 275 if (!strncmp(buf, "virtfs.uid", 10)) { 276 uid = atoi(buf+11); 277 } else if (!strncmp(buf, "virtfs.gid", 10)) { 278 gid = atoi(buf+11); 279 } else if (!strncmp(buf, "virtfs.mode", 11)) { 280 mode = atoi(buf+12); 281 } else if (!strncmp(buf, "virtfs.rdev", 11)) { 282 rdev = atoi(buf+12); 283 } 284 memset(buf, 0, ATTR_MAX); 285 } 286 fclose(fp); 287 goto update_map_file; 288 289 create_map_file: 290 ret = local_create_mapped_attr_dir(ctx, path); 291 if (ret < 0) { 292 goto err_out; 293 } 294 295 update_map_file: 296 fp = local_fopen(attr_path, "w"); 297 if (!fp) { 298 ret = -1; 299 goto err_out; 300 } 301 302 if (credp->fc_uid != -1) { 303 uid = credp->fc_uid; 304 } 305 if (credp->fc_gid != -1) { 306 gid = credp->fc_gid; 307 } 308 if (credp->fc_mode != -1) { 309 mode = credp->fc_mode; 310 } 311 if (credp->fc_rdev != -1) { 312 rdev = credp->fc_rdev; 313 } 314 315 316 if (uid != -1) { 317 fprintf(fp, "virtfs.uid=%d\n", uid); 318 } 319 if (gid != -1) { 320 fprintf(fp, "virtfs.gid=%d\n", gid); 321 } 322 if (mode != -1) { 323 fprintf(fp, "virtfs.mode=%d\n", mode); 324 } 325 if (rdev != -1) { 326 fprintf(fp, "virtfs.rdev=%d\n", rdev); 327 } 328 fclose(fp); 329 330 err_out: 331 g_free(attr_path); 332 return ret; 333 } 334 335 static int local_set_xattr(const char *path, FsCred *credp) 336 { 337 int err; 338 339 if (credp->fc_uid != -1) { 340 uint32_t tmp_uid = cpu_to_le32(credp->fc_uid); 341 err = setxattr(path, "user.virtfs.uid", &tmp_uid, sizeof(uid_t), 0); 342 if (err) { 343 return err; 344 } 345 } 346 if (credp->fc_gid != -1) { 347 uint32_t tmp_gid = cpu_to_le32(credp->fc_gid); 348 err = setxattr(path, "user.virtfs.gid", &tmp_gid, sizeof(gid_t), 0); 349 if (err) { 350 return err; 351 } 352 } 353 if (credp->fc_mode != -1) { 354 uint32_t tmp_mode = cpu_to_le32(credp->fc_mode); 355 err = setxattr(path, "user.virtfs.mode", &tmp_mode, sizeof(mode_t), 0); 356 if (err) { 357 return err; 358 } 359 } 360 if (credp->fc_rdev != -1) { 361 uint64_t tmp_rdev = cpu_to_le64(credp->fc_rdev); 362 err = setxattr(path, "user.virtfs.rdev", &tmp_rdev, sizeof(dev_t), 0); 363 if (err) { 364 return err; 365 } 366 } 367 return 0; 368 } 369 370 static int local_set_mapped_file_attrat(int dirfd, const char *name, 371 FsCred *credp) 372 { 373 FILE *fp; 374 int ret; 375 char buf[ATTR_MAX]; 376 int uid = -1, gid = -1, mode = -1, rdev = -1; 377 int map_dirfd; 378 379 ret = mkdirat(dirfd, VIRTFS_META_DIR, 0700); 380 if (ret < 0 && errno != EEXIST) { 381 return -1; 382 } 383 384 map_dirfd = openat_dir(dirfd, VIRTFS_META_DIR); 385 if (map_dirfd == -1) { 386 return -1; 387 } 388 389 fp = local_fopenat(map_dirfd, name, "r"); 390 if (!fp) { 391 if (errno == ENOENT) { 392 goto update_map_file; 393 } else { 394 close_preserve_errno(map_dirfd); 395 return -1; 396 } 397 } 398 memset(buf, 0, ATTR_MAX); 399 while (fgets(buf, ATTR_MAX, fp)) { 400 if (!strncmp(buf, "virtfs.uid", 10)) { 401 uid = atoi(buf + 11); 402 } else if (!strncmp(buf, "virtfs.gid", 10)) { 403 gid = atoi(buf + 11); 404 } else if (!strncmp(buf, "virtfs.mode", 11)) { 405 mode = atoi(buf + 12); 406 } else if (!strncmp(buf, "virtfs.rdev", 11)) { 407 rdev = atoi(buf + 12); 408 } 409 memset(buf, 0, ATTR_MAX); 410 } 411 fclose(fp); 412 413 update_map_file: 414 fp = local_fopenat(map_dirfd, name, "w"); 415 close_preserve_errno(map_dirfd); 416 if (!fp) { 417 return -1; 418 } 419 420 if (credp->fc_uid != -1) { 421 uid = credp->fc_uid; 422 } 423 if (credp->fc_gid != -1) { 424 gid = credp->fc_gid; 425 } 426 if (credp->fc_mode != -1) { 427 mode = credp->fc_mode; 428 } 429 if (credp->fc_rdev != -1) { 430 rdev = credp->fc_rdev; 431 } 432 433 if (uid != -1) { 434 fprintf(fp, "virtfs.uid=%d\n", uid); 435 } 436 if (gid != -1) { 437 fprintf(fp, "virtfs.gid=%d\n", gid); 438 } 439 if (mode != -1) { 440 fprintf(fp, "virtfs.mode=%d\n", mode); 441 } 442 if (rdev != -1) { 443 fprintf(fp, "virtfs.rdev=%d\n", rdev); 444 } 445 fclose(fp); 446 447 return 0; 448 } 449 450 static int fchmodat_nofollow(int dirfd, const char *name, mode_t mode) 451 { 452 int fd, ret; 453 454 /* FIXME: this should be handled with fchmodat(AT_SYMLINK_NOFOLLOW). 455 * Unfortunately, the linux kernel doesn't implement it yet. As an 456 * alternative, let's open the file and use fchmod() instead. This 457 * may fail depending on the permissions of the file, but it is the 458 * best we can do to avoid TOCTTOU. We first try to open read-only 459 * in case name points to a directory. If that fails, we try write-only 460 * in case name doesn't point to a directory. 461 */ 462 fd = openat_file(dirfd, name, O_RDONLY, 0); 463 if (fd == -1) { 464 /* In case the file is writable-only and isn't a directory. */ 465 if (errno == EACCES) { 466 fd = openat_file(dirfd, name, O_WRONLY, 0); 467 } 468 if (fd == -1 && errno == EISDIR) { 469 errno = EACCES; 470 } 471 } 472 if (fd == -1) { 473 return -1; 474 } 475 ret = fchmod(fd, mode); 476 close_preserve_errno(fd); 477 return ret; 478 } 479 480 static int local_set_xattrat(int dirfd, const char *path, FsCred *credp) 481 { 482 int err; 483 484 if (credp->fc_uid != -1) { 485 uint32_t tmp_uid = cpu_to_le32(credp->fc_uid); 486 err = fsetxattrat_nofollow(dirfd, path, "user.virtfs.uid", &tmp_uid, 487 sizeof(uid_t), 0); 488 if (err) { 489 return err; 490 } 491 } 492 if (credp->fc_gid != -1) { 493 uint32_t tmp_gid = cpu_to_le32(credp->fc_gid); 494 err = fsetxattrat_nofollow(dirfd, path, "user.virtfs.gid", &tmp_gid, 495 sizeof(gid_t), 0); 496 if (err) { 497 return err; 498 } 499 } 500 if (credp->fc_mode != -1) { 501 uint32_t tmp_mode = cpu_to_le32(credp->fc_mode); 502 err = fsetxattrat_nofollow(dirfd, path, "user.virtfs.mode", &tmp_mode, 503 sizeof(mode_t), 0); 504 if (err) { 505 return err; 506 } 507 } 508 if (credp->fc_rdev != -1) { 509 uint64_t tmp_rdev = cpu_to_le64(credp->fc_rdev); 510 err = fsetxattrat_nofollow(dirfd, path, "user.virtfs.rdev", &tmp_rdev, 511 sizeof(dev_t), 0); 512 if (err) { 513 return err; 514 } 515 } 516 return 0; 517 } 518 519 static int local_post_create_passthrough(FsContext *fs_ctx, const char *path, 520 FsCred *credp) 521 { 522 char *buffer; 523 524 buffer = rpath(fs_ctx, path); 525 if (lchown(buffer, credp->fc_uid, credp->fc_gid) < 0) { 526 /* 527 * If we fail to change ownership and if we are 528 * using security model none. Ignore the error 529 */ 530 if ((fs_ctx->export_flags & V9FS_SEC_MASK) != V9FS_SM_NONE) { 531 goto err; 532 } 533 } 534 535 if (chmod(buffer, credp->fc_mode & 07777) < 0) { 536 goto err; 537 } 538 539 g_free(buffer); 540 return 0; 541 err: 542 g_free(buffer); 543 return -1; 544 } 545 546 static ssize_t local_readlink(FsContext *fs_ctx, V9fsPath *fs_path, 547 char *buf, size_t bufsz) 548 { 549 ssize_t tsize = -1; 550 551 if ((fs_ctx->export_flags & V9FS_SM_MAPPED) || 552 (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE)) { 553 int fd; 554 555 fd = local_open_nofollow(fs_ctx, fs_path->data, O_RDONLY, 0); 556 if (fd == -1) { 557 return -1; 558 } 559 do { 560 tsize = read(fd, (void *)buf, bufsz); 561 } while (tsize == -1 && errno == EINTR); 562 close_preserve_errno(fd); 563 } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) || 564 (fs_ctx->export_flags & V9FS_SM_NONE)) { 565 char *dirpath = g_path_get_dirname(fs_path->data); 566 char *name = g_path_get_basename(fs_path->data); 567 int dirfd; 568 569 dirfd = local_opendir_nofollow(fs_ctx, dirpath); 570 if (dirfd == -1) { 571 goto out; 572 } 573 574 tsize = readlinkat(dirfd, name, buf, bufsz); 575 close_preserve_errno(dirfd); 576 out: 577 g_free(name); 578 g_free(dirpath); 579 } 580 return tsize; 581 } 582 583 static int local_close(FsContext *ctx, V9fsFidOpenState *fs) 584 { 585 return close(fs->fd); 586 } 587 588 static int local_closedir(FsContext *ctx, V9fsFidOpenState *fs) 589 { 590 return closedir(fs->dir.stream); 591 } 592 593 static int local_open(FsContext *ctx, V9fsPath *fs_path, 594 int flags, V9fsFidOpenState *fs) 595 { 596 int fd; 597 598 fd = local_open_nofollow(ctx, fs_path->data, flags, 0); 599 if (fd == -1) { 600 return -1; 601 } 602 fs->fd = fd; 603 return fs->fd; 604 } 605 606 static int local_opendir(FsContext *ctx, 607 V9fsPath *fs_path, V9fsFidOpenState *fs) 608 { 609 int dirfd; 610 DIR *stream; 611 612 dirfd = local_opendir_nofollow(ctx, fs_path->data); 613 if (dirfd == -1) { 614 return -1; 615 } 616 617 stream = fdopendir(dirfd); 618 if (!stream) { 619 return -1; 620 } 621 fs->dir.stream = stream; 622 return 0; 623 } 624 625 static void local_rewinddir(FsContext *ctx, V9fsFidOpenState *fs) 626 { 627 rewinddir(fs->dir.stream); 628 } 629 630 static off_t local_telldir(FsContext *ctx, V9fsFidOpenState *fs) 631 { 632 return telldir(fs->dir.stream); 633 } 634 635 static struct dirent *local_readdir(FsContext *ctx, V9fsFidOpenState *fs) 636 { 637 struct dirent *entry; 638 639 again: 640 entry = readdir(fs->dir.stream); 641 if (!entry) { 642 return NULL; 643 } 644 645 if (ctx->export_flags & V9FS_SM_MAPPED) { 646 entry->d_type = DT_UNKNOWN; 647 } else if (ctx->export_flags & V9FS_SM_MAPPED_FILE) { 648 if (!strcmp(entry->d_name, VIRTFS_META_DIR)) { 649 /* skp the meta data directory */ 650 goto again; 651 } 652 entry->d_type = DT_UNKNOWN; 653 } 654 655 return entry; 656 } 657 658 static void local_seekdir(FsContext *ctx, V9fsFidOpenState *fs, off_t off) 659 { 660 seekdir(fs->dir.stream, off); 661 } 662 663 static ssize_t local_preadv(FsContext *ctx, V9fsFidOpenState *fs, 664 const struct iovec *iov, 665 int iovcnt, off_t offset) 666 { 667 #ifdef CONFIG_PREADV 668 return preadv(fs->fd, iov, iovcnt, offset); 669 #else 670 int err = lseek(fs->fd, offset, SEEK_SET); 671 if (err == -1) { 672 return err; 673 } else { 674 return readv(fs->fd, iov, iovcnt); 675 } 676 #endif 677 } 678 679 static ssize_t local_pwritev(FsContext *ctx, V9fsFidOpenState *fs, 680 const struct iovec *iov, 681 int iovcnt, off_t offset) 682 { 683 ssize_t ret; 684 #ifdef CONFIG_PREADV 685 ret = pwritev(fs->fd, iov, iovcnt, offset); 686 #else 687 int err = lseek(fs->fd, offset, SEEK_SET); 688 if (err == -1) { 689 return err; 690 } else { 691 ret = writev(fs->fd, iov, iovcnt); 692 } 693 #endif 694 #ifdef CONFIG_SYNC_FILE_RANGE 695 if (ret > 0 && ctx->export_flags & V9FS_IMMEDIATE_WRITEOUT) { 696 /* 697 * Initiate a writeback. This is not a data integrity sync. 698 * We want to ensure that we don't leave dirty pages in the cache 699 * after write when writeout=immediate is sepcified. 700 */ 701 sync_file_range(fs->fd, offset, ret, 702 SYNC_FILE_RANGE_WAIT_BEFORE | SYNC_FILE_RANGE_WRITE); 703 } 704 #endif 705 return ret; 706 } 707 708 static int local_chmod(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp) 709 { 710 char *dirpath = g_path_get_dirname(fs_path->data); 711 char *name = g_path_get_basename(fs_path->data); 712 int ret = -1; 713 int dirfd; 714 715 dirfd = local_opendir_nofollow(fs_ctx, dirpath); 716 if (dirfd == -1) { 717 goto out; 718 } 719 720 if (fs_ctx->export_flags & V9FS_SM_MAPPED) { 721 ret = local_set_xattrat(dirfd, name, credp); 722 } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) { 723 ret = local_set_mapped_file_attrat(dirfd, name, credp); 724 } else if (fs_ctx->export_flags & V9FS_SM_PASSTHROUGH || 725 fs_ctx->export_flags & V9FS_SM_NONE) { 726 ret = fchmodat_nofollow(dirfd, name, credp->fc_mode); 727 } 728 close_preserve_errno(dirfd); 729 730 out: 731 g_free(dirpath); 732 g_free(name); 733 return ret; 734 } 735 736 static int local_mknod(FsContext *fs_ctx, V9fsPath *dir_path, 737 const char *name, FsCred *credp) 738 { 739 char *path; 740 int err = -1; 741 int serrno = 0; 742 V9fsString fullname; 743 char *buffer = NULL; 744 745 v9fs_string_init(&fullname); 746 v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name); 747 path = fullname.data; 748 749 /* Determine the security model */ 750 if (fs_ctx->export_flags & V9FS_SM_MAPPED) { 751 buffer = rpath(fs_ctx, path); 752 err = mknod(buffer, SM_LOCAL_MODE_BITS|S_IFREG, 0); 753 if (err == -1) { 754 goto out; 755 } 756 err = local_set_xattr(buffer, credp); 757 if (err == -1) { 758 serrno = errno; 759 goto err_end; 760 } 761 } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) { 762 763 buffer = rpath(fs_ctx, path); 764 err = mknod(buffer, SM_LOCAL_MODE_BITS|S_IFREG, 0); 765 if (err == -1) { 766 goto out; 767 } 768 err = local_set_mapped_file_attr(fs_ctx, path, credp); 769 if (err == -1) { 770 serrno = errno; 771 goto err_end; 772 } 773 } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) || 774 (fs_ctx->export_flags & V9FS_SM_NONE)) { 775 buffer = rpath(fs_ctx, path); 776 err = mknod(buffer, credp->fc_mode, credp->fc_rdev); 777 if (err == -1) { 778 goto out; 779 } 780 err = local_post_create_passthrough(fs_ctx, path, credp); 781 if (err == -1) { 782 serrno = errno; 783 goto err_end; 784 } 785 } 786 goto out; 787 788 err_end: 789 remove(buffer); 790 errno = serrno; 791 out: 792 g_free(buffer); 793 v9fs_string_free(&fullname); 794 return err; 795 } 796 797 static int local_mkdir(FsContext *fs_ctx, V9fsPath *dir_path, 798 const char *name, FsCred *credp) 799 { 800 char *path; 801 int err = -1; 802 int serrno = 0; 803 V9fsString fullname; 804 char *buffer = NULL; 805 806 v9fs_string_init(&fullname); 807 v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name); 808 path = fullname.data; 809 810 /* Determine the security model */ 811 if (fs_ctx->export_flags & V9FS_SM_MAPPED) { 812 buffer = rpath(fs_ctx, path); 813 err = mkdir(buffer, SM_LOCAL_DIR_MODE_BITS); 814 if (err == -1) { 815 goto out; 816 } 817 credp->fc_mode = credp->fc_mode|S_IFDIR; 818 err = local_set_xattr(buffer, credp); 819 if (err == -1) { 820 serrno = errno; 821 goto err_end; 822 } 823 } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) { 824 buffer = rpath(fs_ctx, path); 825 err = mkdir(buffer, SM_LOCAL_DIR_MODE_BITS); 826 if (err == -1) { 827 goto out; 828 } 829 credp->fc_mode = credp->fc_mode|S_IFDIR; 830 err = local_set_mapped_file_attr(fs_ctx, path, credp); 831 if (err == -1) { 832 serrno = errno; 833 goto err_end; 834 } 835 } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) || 836 (fs_ctx->export_flags & V9FS_SM_NONE)) { 837 buffer = rpath(fs_ctx, path); 838 err = mkdir(buffer, credp->fc_mode); 839 if (err == -1) { 840 goto out; 841 } 842 err = local_post_create_passthrough(fs_ctx, path, credp); 843 if (err == -1) { 844 serrno = errno; 845 goto err_end; 846 } 847 } 848 goto out; 849 850 err_end: 851 remove(buffer); 852 errno = serrno; 853 out: 854 g_free(buffer); 855 v9fs_string_free(&fullname); 856 return err; 857 } 858 859 static int local_fstat(FsContext *fs_ctx, int fid_type, 860 V9fsFidOpenState *fs, struct stat *stbuf) 861 { 862 int err, fd; 863 864 if (fid_type == P9_FID_DIR) { 865 fd = dirfd(fs->dir.stream); 866 } else { 867 fd = fs->fd; 868 } 869 870 err = fstat(fd, stbuf); 871 if (err) { 872 return err; 873 } 874 if (fs_ctx->export_flags & V9FS_SM_MAPPED) { 875 /* Actual credentials are part of extended attrs */ 876 uid_t tmp_uid; 877 gid_t tmp_gid; 878 mode_t tmp_mode; 879 dev_t tmp_dev; 880 881 if (fgetxattr(fd, "user.virtfs.uid", &tmp_uid, sizeof(uid_t)) > 0) { 882 stbuf->st_uid = le32_to_cpu(tmp_uid); 883 } 884 if (fgetxattr(fd, "user.virtfs.gid", &tmp_gid, sizeof(gid_t)) > 0) { 885 stbuf->st_gid = le32_to_cpu(tmp_gid); 886 } 887 if (fgetxattr(fd, "user.virtfs.mode", &tmp_mode, sizeof(mode_t)) > 0) { 888 stbuf->st_mode = le32_to_cpu(tmp_mode); 889 } 890 if (fgetxattr(fd, "user.virtfs.rdev", &tmp_dev, sizeof(dev_t)) > 0) { 891 stbuf->st_rdev = le64_to_cpu(tmp_dev); 892 } 893 } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) { 894 errno = EOPNOTSUPP; 895 return -1; 896 } 897 return err; 898 } 899 900 static int local_open2(FsContext *fs_ctx, V9fsPath *dir_path, const char *name, 901 int flags, FsCred *credp, V9fsFidOpenState *fs) 902 { 903 char *path; 904 int fd = -1; 905 int err = -1; 906 int serrno = 0; 907 V9fsString fullname; 908 char *buffer = NULL; 909 910 /* 911 * Mark all the open to not follow symlinks 912 */ 913 flags |= O_NOFOLLOW; 914 915 v9fs_string_init(&fullname); 916 v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name); 917 path = fullname.data; 918 919 /* Determine the security model */ 920 if (fs_ctx->export_flags & V9FS_SM_MAPPED) { 921 buffer = rpath(fs_ctx, path); 922 fd = open(buffer, flags, SM_LOCAL_MODE_BITS); 923 if (fd == -1) { 924 err = fd; 925 goto out; 926 } 927 credp->fc_mode = credp->fc_mode|S_IFREG; 928 /* Set cleint credentials in xattr */ 929 err = local_set_xattr(buffer, credp); 930 if (err == -1) { 931 serrno = errno; 932 goto err_end; 933 } 934 } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) { 935 buffer = rpath(fs_ctx, path); 936 fd = open(buffer, flags, SM_LOCAL_MODE_BITS); 937 if (fd == -1) { 938 err = fd; 939 goto out; 940 } 941 credp->fc_mode = credp->fc_mode|S_IFREG; 942 /* Set client credentials in .virtfs_metadata directory files */ 943 err = local_set_mapped_file_attr(fs_ctx, path, credp); 944 if (err == -1) { 945 serrno = errno; 946 goto err_end; 947 } 948 } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) || 949 (fs_ctx->export_flags & V9FS_SM_NONE)) { 950 buffer = rpath(fs_ctx, path); 951 fd = open(buffer, flags, credp->fc_mode); 952 if (fd == -1) { 953 err = fd; 954 goto out; 955 } 956 err = local_post_create_passthrough(fs_ctx, path, credp); 957 if (err == -1) { 958 serrno = errno; 959 goto err_end; 960 } 961 } 962 err = fd; 963 fs->fd = fd; 964 goto out; 965 966 err_end: 967 close(fd); 968 remove(buffer); 969 errno = serrno; 970 out: 971 g_free(buffer); 972 v9fs_string_free(&fullname); 973 return err; 974 } 975 976 977 static int local_symlink(FsContext *fs_ctx, const char *oldpath, 978 V9fsPath *dir_path, const char *name, FsCred *credp) 979 { 980 int err = -1; 981 int serrno = 0; 982 char *newpath; 983 V9fsString fullname; 984 char *buffer = NULL; 985 986 v9fs_string_init(&fullname); 987 v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name); 988 newpath = fullname.data; 989 990 /* Determine the security model */ 991 if (fs_ctx->export_flags & V9FS_SM_MAPPED) { 992 int fd; 993 ssize_t oldpath_size, write_size; 994 buffer = rpath(fs_ctx, newpath); 995 fd = open(buffer, O_CREAT|O_EXCL|O_RDWR|O_NOFOLLOW, SM_LOCAL_MODE_BITS); 996 if (fd == -1) { 997 err = fd; 998 goto out; 999 } 1000 /* Write the oldpath (target) to the file. */ 1001 oldpath_size = strlen(oldpath); 1002 do { 1003 write_size = write(fd, (void *)oldpath, oldpath_size); 1004 } while (write_size == -1 && errno == EINTR); 1005 1006 if (write_size != oldpath_size) { 1007 serrno = errno; 1008 close(fd); 1009 err = -1; 1010 goto err_end; 1011 } 1012 close(fd); 1013 /* Set cleint credentials in symlink's xattr */ 1014 credp->fc_mode = credp->fc_mode|S_IFLNK; 1015 err = local_set_xattr(buffer, credp); 1016 if (err == -1) { 1017 serrno = errno; 1018 goto err_end; 1019 } 1020 } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) { 1021 int fd; 1022 ssize_t oldpath_size, write_size; 1023 buffer = rpath(fs_ctx, newpath); 1024 fd = open(buffer, O_CREAT|O_EXCL|O_RDWR|O_NOFOLLOW, SM_LOCAL_MODE_BITS); 1025 if (fd == -1) { 1026 err = fd; 1027 goto out; 1028 } 1029 /* Write the oldpath (target) to the file. */ 1030 oldpath_size = strlen(oldpath); 1031 do { 1032 write_size = write(fd, (void *)oldpath, oldpath_size); 1033 } while (write_size == -1 && errno == EINTR); 1034 1035 if (write_size != oldpath_size) { 1036 serrno = errno; 1037 close(fd); 1038 err = -1; 1039 goto err_end; 1040 } 1041 close(fd); 1042 /* Set cleint credentials in symlink's xattr */ 1043 credp->fc_mode = credp->fc_mode|S_IFLNK; 1044 err = local_set_mapped_file_attr(fs_ctx, newpath, credp); 1045 if (err == -1) { 1046 serrno = errno; 1047 goto err_end; 1048 } 1049 } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) || 1050 (fs_ctx->export_flags & V9FS_SM_NONE)) { 1051 buffer = rpath(fs_ctx, newpath); 1052 err = symlink(oldpath, buffer); 1053 if (err) { 1054 goto out; 1055 } 1056 err = lchown(buffer, credp->fc_uid, credp->fc_gid); 1057 if (err == -1) { 1058 /* 1059 * If we fail to change ownership and if we are 1060 * using security model none. Ignore the error 1061 */ 1062 if ((fs_ctx->export_flags & V9FS_SEC_MASK) != V9FS_SM_NONE) { 1063 serrno = errno; 1064 goto err_end; 1065 } else 1066 err = 0; 1067 } 1068 } 1069 goto out; 1070 1071 err_end: 1072 remove(buffer); 1073 errno = serrno; 1074 out: 1075 g_free(buffer); 1076 v9fs_string_free(&fullname); 1077 return err; 1078 } 1079 1080 static int local_link(FsContext *ctx, V9fsPath *oldpath, 1081 V9fsPath *dirpath, const char *name) 1082 { 1083 char *odirpath = g_path_get_dirname(oldpath->data); 1084 char *oname = g_path_get_basename(oldpath->data); 1085 int ret = -1; 1086 int odirfd, ndirfd; 1087 1088 odirfd = local_opendir_nofollow(ctx, odirpath); 1089 if (odirfd == -1) { 1090 goto out; 1091 } 1092 1093 ndirfd = local_opendir_nofollow(ctx, dirpath->data); 1094 if (ndirfd == -1) { 1095 close_preserve_errno(odirfd); 1096 goto out; 1097 } 1098 1099 ret = linkat(odirfd, oname, ndirfd, name, 0); 1100 if (ret < 0) { 1101 goto out_close; 1102 } 1103 1104 /* now link the virtfs_metadata files */ 1105 if (ctx->export_flags & V9FS_SM_MAPPED_FILE) { 1106 int omap_dirfd, nmap_dirfd; 1107 1108 ret = mkdirat(ndirfd, VIRTFS_META_DIR, 0700); 1109 if (ret < 0 && errno != EEXIST) { 1110 goto err_undo_link; 1111 } 1112 1113 omap_dirfd = openat_dir(odirfd, VIRTFS_META_DIR); 1114 if (omap_dirfd == -1) { 1115 goto err; 1116 } 1117 1118 nmap_dirfd = openat_dir(ndirfd, VIRTFS_META_DIR); 1119 if (nmap_dirfd == -1) { 1120 close_preserve_errno(omap_dirfd); 1121 goto err; 1122 } 1123 1124 ret = linkat(omap_dirfd, oname, nmap_dirfd, name, 0); 1125 close_preserve_errno(nmap_dirfd); 1126 close_preserve_errno(omap_dirfd); 1127 if (ret < 0 && errno != ENOENT) { 1128 goto err_undo_link; 1129 } 1130 1131 ret = 0; 1132 } 1133 goto out_close; 1134 1135 err: 1136 ret = -1; 1137 err_undo_link: 1138 unlinkat_preserve_errno(ndirfd, name, 0); 1139 out_close: 1140 close_preserve_errno(ndirfd); 1141 close_preserve_errno(odirfd); 1142 out: 1143 g_free(oname); 1144 g_free(odirpath); 1145 return ret; 1146 } 1147 1148 static int local_truncate(FsContext *ctx, V9fsPath *fs_path, off_t size) 1149 { 1150 int fd, ret; 1151 1152 fd = local_open_nofollow(ctx, fs_path->data, O_WRONLY, 0); 1153 if (fd == -1) { 1154 return -1; 1155 } 1156 ret = ftruncate(fd, size); 1157 close_preserve_errno(fd); 1158 return ret; 1159 } 1160 1161 static int local_chown(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp) 1162 { 1163 char *dirpath = g_path_get_dirname(fs_path->data); 1164 char *name = g_path_get_basename(fs_path->data); 1165 int ret = -1; 1166 int dirfd; 1167 1168 dirfd = local_opendir_nofollow(fs_ctx, dirpath); 1169 if (dirfd == -1) { 1170 goto out; 1171 } 1172 1173 if ((credp->fc_uid == -1 && credp->fc_gid == -1) || 1174 (fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) || 1175 (fs_ctx->export_flags & V9FS_SM_NONE)) { 1176 ret = fchownat(dirfd, name, credp->fc_uid, credp->fc_gid, 1177 AT_SYMLINK_NOFOLLOW); 1178 } else if (fs_ctx->export_flags & V9FS_SM_MAPPED) { 1179 ret = local_set_xattrat(dirfd, name, credp); 1180 } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) { 1181 ret = local_set_mapped_file_attrat(dirfd, name, credp); 1182 } 1183 1184 close_preserve_errno(dirfd); 1185 out: 1186 g_free(name); 1187 g_free(dirpath); 1188 return ret; 1189 } 1190 1191 static int local_utimensat(FsContext *s, V9fsPath *fs_path, 1192 const struct timespec *buf) 1193 { 1194 char *dirpath = g_path_get_dirname(fs_path->data); 1195 char *name = g_path_get_basename(fs_path->data); 1196 int dirfd, ret = -1; 1197 1198 dirfd = local_opendir_nofollow(s, dirpath); 1199 if (dirfd == -1) { 1200 goto out; 1201 } 1202 1203 ret = utimensat(dirfd, name, buf, AT_SYMLINK_NOFOLLOW); 1204 close_preserve_errno(dirfd); 1205 out: 1206 g_free(dirpath); 1207 g_free(name); 1208 return ret; 1209 } 1210 1211 static int local_unlinkat_common(FsContext *ctx, int dirfd, const char *name, 1212 int flags) 1213 { 1214 int ret = -1; 1215 1216 if (ctx->export_flags & V9FS_SM_MAPPED_FILE) { 1217 int map_dirfd; 1218 1219 if (flags == AT_REMOVEDIR) { 1220 int fd; 1221 1222 fd = openat(dirfd, name, O_RDONLY | O_DIRECTORY | O_PATH); 1223 if (fd == -1) { 1224 goto err_out; 1225 } 1226 /* 1227 * If directory remove .virtfs_metadata contained in the 1228 * directory 1229 */ 1230 ret = unlinkat(fd, VIRTFS_META_DIR, AT_REMOVEDIR); 1231 close_preserve_errno(fd); 1232 if (ret < 0 && errno != ENOENT) { 1233 /* 1234 * We didn't had the .virtfs_metadata file. May be file created 1235 * in non-mapped mode ?. Ignore ENOENT. 1236 */ 1237 goto err_out; 1238 } 1239 } 1240 /* 1241 * Now remove the name from parent directory 1242 * .virtfs_metadata directory. 1243 */ 1244 map_dirfd = openat_dir(dirfd, VIRTFS_META_DIR); 1245 ret = unlinkat(map_dirfd, name, 0); 1246 close_preserve_errno(map_dirfd); 1247 if (ret < 0 && errno != ENOENT) { 1248 /* 1249 * We didn't had the .virtfs_metadata file. May be file created 1250 * in non-mapped mode ?. Ignore ENOENT. 1251 */ 1252 goto err_out; 1253 } 1254 } 1255 1256 ret = unlinkat(dirfd, name, flags); 1257 err_out: 1258 return ret; 1259 } 1260 1261 static int local_remove(FsContext *ctx, const char *path) 1262 { 1263 struct stat stbuf; 1264 char *dirpath = g_path_get_dirname(path); 1265 char *name = g_path_get_basename(path); 1266 int flags = 0; 1267 int dirfd; 1268 int err = -1; 1269 1270 dirfd = local_opendir_nofollow(ctx, dirpath); 1271 if (dirfd) { 1272 goto out; 1273 } 1274 1275 if (fstatat(dirfd, path, &stbuf, AT_SYMLINK_NOFOLLOW) < 0) { 1276 goto err_out; 1277 } 1278 1279 if (S_ISDIR(stbuf.st_mode)) { 1280 flags |= AT_REMOVEDIR; 1281 } 1282 1283 err = local_unlinkat_common(ctx, dirfd, name, flags); 1284 err_out: 1285 close_preserve_errno(dirfd); 1286 out: 1287 g_free(name); 1288 g_free(dirpath); 1289 return err; 1290 } 1291 1292 static int local_fsync(FsContext *ctx, int fid_type, 1293 V9fsFidOpenState *fs, int datasync) 1294 { 1295 int fd; 1296 1297 if (fid_type == P9_FID_DIR) { 1298 fd = dirfd(fs->dir.stream); 1299 } else { 1300 fd = fs->fd; 1301 } 1302 1303 if (datasync) { 1304 return qemu_fdatasync(fd); 1305 } else { 1306 return fsync(fd); 1307 } 1308 } 1309 1310 static int local_statfs(FsContext *s, V9fsPath *fs_path, struct statfs *stbuf) 1311 { 1312 int fd, ret; 1313 1314 fd = local_open_nofollow(s, fs_path->data, O_RDONLY, 0); 1315 ret = fstatfs(fd, stbuf); 1316 close_preserve_errno(fd); 1317 return ret; 1318 } 1319 1320 static ssize_t local_lgetxattr(FsContext *ctx, V9fsPath *fs_path, 1321 const char *name, void *value, size_t size) 1322 { 1323 char *path = fs_path->data; 1324 1325 return v9fs_get_xattr(ctx, path, name, value, size); 1326 } 1327 1328 static ssize_t local_llistxattr(FsContext *ctx, V9fsPath *fs_path, 1329 void *value, size_t size) 1330 { 1331 char *path = fs_path->data; 1332 1333 return v9fs_list_xattr(ctx, path, value, size); 1334 } 1335 1336 static int local_lsetxattr(FsContext *ctx, V9fsPath *fs_path, const char *name, 1337 void *value, size_t size, int flags) 1338 { 1339 char *path = fs_path->data; 1340 1341 return v9fs_set_xattr(ctx, path, name, value, size, flags); 1342 } 1343 1344 static int local_lremovexattr(FsContext *ctx, V9fsPath *fs_path, 1345 const char *name) 1346 { 1347 char *path = fs_path->data; 1348 1349 return v9fs_remove_xattr(ctx, path, name); 1350 } 1351 1352 static int local_name_to_path(FsContext *ctx, V9fsPath *dir_path, 1353 const char *name, V9fsPath *target) 1354 { 1355 if (dir_path) { 1356 v9fs_path_sprintf(target, "%s/%s", dir_path->data, name); 1357 } else { 1358 v9fs_path_sprintf(target, "%s", name); 1359 } 1360 return 0; 1361 } 1362 1363 static int local_renameat(FsContext *ctx, V9fsPath *olddir, 1364 const char *old_name, V9fsPath *newdir, 1365 const char *new_name) 1366 { 1367 int ret; 1368 int odirfd, ndirfd; 1369 1370 odirfd = local_opendir_nofollow(ctx, olddir->data); 1371 if (odirfd == -1) { 1372 return -1; 1373 } 1374 1375 ndirfd = local_opendir_nofollow(ctx, newdir->data); 1376 if (ndirfd == -1) { 1377 close_preserve_errno(odirfd); 1378 return -1; 1379 } 1380 1381 ret = renameat(odirfd, old_name, ndirfd, new_name); 1382 if (ret < 0) { 1383 goto out; 1384 } 1385 1386 if (ctx->export_flags & V9FS_SM_MAPPED_FILE) { 1387 int omap_dirfd, nmap_dirfd; 1388 1389 ret = mkdirat(ndirfd, VIRTFS_META_DIR, 0700); 1390 if (ret < 0 && errno != EEXIST) { 1391 goto err_undo_rename; 1392 } 1393 1394 omap_dirfd = openat_dir(odirfd, VIRTFS_META_DIR); 1395 if (omap_dirfd == -1) { 1396 goto err; 1397 } 1398 1399 nmap_dirfd = openat_dir(ndirfd, VIRTFS_META_DIR); 1400 if (nmap_dirfd == -1) { 1401 close_preserve_errno(omap_dirfd); 1402 goto err; 1403 } 1404 1405 /* rename the .virtfs_metadata files */ 1406 ret = renameat(omap_dirfd, old_name, nmap_dirfd, new_name); 1407 close_preserve_errno(nmap_dirfd); 1408 close_preserve_errno(omap_dirfd); 1409 if (ret < 0 && errno != ENOENT) { 1410 goto err_undo_rename; 1411 } 1412 1413 ret = 0; 1414 } 1415 goto out; 1416 1417 err: 1418 ret = -1; 1419 err_undo_rename: 1420 renameat_preserve_errno(ndirfd, new_name, odirfd, old_name); 1421 out: 1422 close_preserve_errno(ndirfd); 1423 close_preserve_errno(odirfd); 1424 return ret; 1425 } 1426 1427 static void v9fs_path_init_dirname(V9fsPath *path, const char *str) 1428 { 1429 path->data = g_path_get_dirname(str); 1430 path->size = strlen(path->data) + 1; 1431 } 1432 1433 static int local_rename(FsContext *ctx, const char *oldpath, 1434 const char *newpath) 1435 { 1436 int err; 1437 char *oname = g_path_get_basename(oldpath); 1438 char *nname = g_path_get_basename(newpath); 1439 V9fsPath olddir, newdir; 1440 1441 v9fs_path_init_dirname(&olddir, oldpath); 1442 v9fs_path_init_dirname(&newdir, newpath); 1443 1444 err = local_renameat(ctx, &olddir, oname, &newdir, nname); 1445 1446 v9fs_path_free(&newdir); 1447 v9fs_path_free(&olddir); 1448 g_free(nname); 1449 g_free(oname); 1450 1451 return err; 1452 } 1453 1454 static int local_unlinkat(FsContext *ctx, V9fsPath *dir, 1455 const char *name, int flags) 1456 { 1457 int ret; 1458 int dirfd; 1459 1460 dirfd = local_opendir_nofollow(ctx, dir->data); 1461 if (dirfd == -1) { 1462 return -1; 1463 } 1464 1465 ret = local_unlinkat_common(ctx, dirfd, name, flags); 1466 close_preserve_errno(dirfd); 1467 return ret; 1468 } 1469 1470 static int local_ioc_getversion(FsContext *ctx, V9fsPath *path, 1471 mode_t st_mode, uint64_t *st_gen) 1472 { 1473 #ifdef FS_IOC_GETVERSION 1474 int err; 1475 V9fsFidOpenState fid_open; 1476 1477 /* 1478 * Do not try to open special files like device nodes, fifos etc 1479 * We can get fd for regular files and directories only 1480 */ 1481 if (!S_ISREG(st_mode) && !S_ISDIR(st_mode)) { 1482 errno = ENOTTY; 1483 return -1; 1484 } 1485 err = local_open(ctx, path, O_RDONLY, &fid_open); 1486 if (err < 0) { 1487 return err; 1488 } 1489 err = ioctl(fid_open.fd, FS_IOC_GETVERSION, st_gen); 1490 local_close(ctx, &fid_open); 1491 return err; 1492 #else 1493 errno = ENOTTY; 1494 return -1; 1495 #endif 1496 } 1497 1498 static int local_init(FsContext *ctx) 1499 { 1500 struct statfs stbuf; 1501 LocalData *data = g_malloc(sizeof(*data)); 1502 1503 data->mountfd = open(ctx->fs_root, O_DIRECTORY | O_RDONLY); 1504 if (data->mountfd == -1) { 1505 goto err; 1506 } 1507 1508 #ifdef FS_IOC_GETVERSION 1509 /* 1510 * use ioc_getversion only if the ioctl is definied 1511 */ 1512 if (fstatfs(data->mountfd, &stbuf) < 0) { 1513 close_preserve_errno(data->mountfd); 1514 goto err; 1515 } 1516 switch (stbuf.f_type) { 1517 case EXT2_SUPER_MAGIC: 1518 case BTRFS_SUPER_MAGIC: 1519 case REISERFS_SUPER_MAGIC: 1520 case XFS_SUPER_MAGIC: 1521 ctx->exops.get_st_gen = local_ioc_getversion; 1522 break; 1523 } 1524 #endif 1525 1526 if (ctx->export_flags & V9FS_SM_PASSTHROUGH) { 1527 ctx->xops = passthrough_xattr_ops; 1528 } else if (ctx->export_flags & V9FS_SM_MAPPED) { 1529 ctx->xops = mapped_xattr_ops; 1530 } else if (ctx->export_flags & V9FS_SM_NONE) { 1531 ctx->xops = none_xattr_ops; 1532 } else if (ctx->export_flags & V9FS_SM_MAPPED_FILE) { 1533 /* 1534 * xattr operation for mapped-file and passthrough 1535 * remain same. 1536 */ 1537 ctx->xops = passthrough_xattr_ops; 1538 } 1539 ctx->export_flags |= V9FS_PATHNAME_FSCONTEXT; 1540 1541 ctx->private = data; 1542 return 0; 1543 1544 err: 1545 g_free(data); 1546 return -1; 1547 } 1548 1549 static void local_cleanup(FsContext *ctx) 1550 { 1551 LocalData *data = ctx->private; 1552 1553 close(data->mountfd); 1554 g_free(data); 1555 } 1556 1557 static int local_parse_opts(QemuOpts *opts, struct FsDriverEntry *fse) 1558 { 1559 const char *sec_model = qemu_opt_get(opts, "security_model"); 1560 const char *path = qemu_opt_get(opts, "path"); 1561 1562 if (!sec_model) { 1563 error_report("Security model not specified, local fs needs security model"); 1564 error_printf("valid options are:" 1565 "\tsecurity_model=[passthrough|mapped-xattr|mapped-file|none]\n"); 1566 return -1; 1567 } 1568 1569 if (!strcmp(sec_model, "passthrough")) { 1570 fse->export_flags |= V9FS_SM_PASSTHROUGH; 1571 } else if (!strcmp(sec_model, "mapped") || 1572 !strcmp(sec_model, "mapped-xattr")) { 1573 fse->export_flags |= V9FS_SM_MAPPED; 1574 } else if (!strcmp(sec_model, "none")) { 1575 fse->export_flags |= V9FS_SM_NONE; 1576 } else if (!strcmp(sec_model, "mapped-file")) { 1577 fse->export_flags |= V9FS_SM_MAPPED_FILE; 1578 } else { 1579 error_report("Invalid security model %s specified", sec_model); 1580 error_printf("valid options are:" 1581 "\t[passthrough|mapped-xattr|mapped-file|none]\n"); 1582 return -1; 1583 } 1584 1585 if (!path) { 1586 error_report("fsdev: No path specified"); 1587 return -1; 1588 } 1589 fse->path = g_strdup(path); 1590 1591 return 0; 1592 } 1593 1594 FileOperations local_ops = { 1595 .parse_opts = local_parse_opts, 1596 .init = local_init, 1597 .cleanup = local_cleanup, 1598 .lstat = local_lstat, 1599 .readlink = local_readlink, 1600 .close = local_close, 1601 .closedir = local_closedir, 1602 .open = local_open, 1603 .opendir = local_opendir, 1604 .rewinddir = local_rewinddir, 1605 .telldir = local_telldir, 1606 .readdir = local_readdir, 1607 .seekdir = local_seekdir, 1608 .preadv = local_preadv, 1609 .pwritev = local_pwritev, 1610 .chmod = local_chmod, 1611 .mknod = local_mknod, 1612 .mkdir = local_mkdir, 1613 .fstat = local_fstat, 1614 .open2 = local_open2, 1615 .symlink = local_symlink, 1616 .link = local_link, 1617 .truncate = local_truncate, 1618 .rename = local_rename, 1619 .chown = local_chown, 1620 .utimensat = local_utimensat, 1621 .remove = local_remove, 1622 .fsync = local_fsync, 1623 .statfs = local_statfs, 1624 .lgetxattr = local_lgetxattr, 1625 .llistxattr = local_llistxattr, 1626 .lsetxattr = local_lsetxattr, 1627 .lremovexattr = local_lremovexattr, 1628 .name_to_path = local_name_to_path, 1629 .renameat = local_renameat, 1630 .unlinkat = local_unlinkat, 1631 }; 1632