1 /* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #define LOG_TAG "sdcard" 18 19 #include <ctype.h> 20 #include <dirent.h> 21 #include <errno.h> 22 #include <fcntl.h> 23 #include <inttypes.h> 24 #include <limits.h> 25 #include <linux/fuse.h> 26 #include <pthread.h> 27 #include <stdio.h> 28 #include <stdlib.h> 29 #include <string.h> 30 #include <sys/inotify.h> 31 #include <sys/mount.h> 32 #include <sys/resource.h> 33 #include <sys/stat.h> 34 #include <sys/statfs.h> 35 #include <sys/time.h> 36 #include <sys/uio.h> 37 #include <unistd.h> 38 39 #include <cutils/fs.h> 40 #include <cutils/hashmap.h> 41 #include <cutils/log.h> 42 #include <cutils/multiuser.h> 43 44 #include <private/android_filesystem_config.h> 45 46 /* README 47 * 48 * What is this? 49 * 50 * sdcard is a program that uses FUSE to emulate FAT-on-sdcard style 51 * directory permissions (all files are given fixed owner, group, and 52 * permissions at creation, owner, group, and permissions are not 53 * changeable, symlinks and hardlinks are not createable, etc. 54 * 55 * See usage() for command line options. 56 * 57 * It must be run as root, but will drop to requested UID/GID as soon as it 58 * mounts a filesystem. It will refuse to run if requested UID/GID are zero. 59 * 60 * Things I believe to be true: 61 * 62 * - ops that return a fuse_entry (LOOKUP, MKNOD, MKDIR, LINK, SYMLINK, 63 * CREAT) must bump that node's refcount 64 * - don't forget that FORGET can forget multiple references (req->nlookup) 65 * - if an op that returns a fuse_entry fails writing the reply to the 66 * kernel, you must rollback the refcount to reflect the reference the 67 * kernel did not actually acquire 68 * 69 * This daemon can also derive custom filesystem permissions based on directory 70 * structure when requested. These custom permissions support several features: 71 * 72 * - Apps can access their own files in /Android/data/com.example/ without 73 * requiring any additional GIDs. 74 * - Separate permissions for protecting directories like Pictures and Music. 75 * - Multi-user separation on the same physical device. 76 * 77 * The derived permissions look like this: 78 * 79 * rwxrwx--x root:sdcard_rw / 80 * rwxrwx--- root:sdcard_pics /Pictures 81 * rwxrwx--- root:sdcard_av /Music 82 * 83 * rwxrwx--x root:sdcard_rw /Android 84 * rwxrwx--x root:sdcard_rw /Android/data 85 * rwxrwx--- u0_a12:sdcard_rw /Android/data/com.example 86 * rwxrwx--x root:sdcard_rw /Android/obb/ 87 * rwxrwx--- u0_a12:sdcard_rw /Android/obb/com.example 88 * 89 * rwxrwx--- root:sdcard_all /Android/user 90 * rwxrwx--x root:sdcard_rw /Android/user/10 91 * rwxrwx--- u10_a12:sdcard_rw /Android/user/10/Android/data/com.example 92 */ 93 94 #define FUSE_TRACE 0 95 96 #if FUSE_TRACE 97 #define TRACE(x...) ALOGD(x) 98 #else 99 #define TRACE(x...) do {} while (0) 100 #endif 101 102 #define ERROR(x...) ALOGE(x) 103 104 #define FUSE_UNKNOWN_INO 0xffffffff 105 106 /* Maximum number of bytes to write in one request. */ 107 #define MAX_WRITE (256 * 1024) 108 109 /* Maximum number of bytes to read in one request. */ 110 #define MAX_READ (128 * 1024) 111 112 /* Largest possible request. 113 * The request size is bounded by the maximum size of a FUSE_WRITE request because it has 114 * the largest possible data payload. */ 115 #define MAX_REQUEST_SIZE (sizeof(struct fuse_in_header) + sizeof(struct fuse_write_in) + MAX_WRITE) 116 117 /* Default number of threads. */ 118 #define DEFAULT_NUM_THREADS 2 119 120 /* Pseudo-error constant used to indicate that no fuse status is needed 121 * or that a reply has already been written. */ 122 #define NO_STATUS 1 123 124 /* Path to system-provided mapping of package name to appIds */ 125 static const char* const kPackagesListFile = "/data/system/packages.list"; 126 127 /* Supplementary groups to execute with */ 128 static const gid_t kGroups[1] = { AID_PACKAGE_INFO }; 129 130 /* Permission mode for a specific node. Controls how file permissions 131 * are derived for children nodes. */ 132 typedef enum { 133 /* Nothing special; this node should just inherit from its parent. */ 134 PERM_INHERIT, 135 /* This node is one level above a normal root; used for legacy layouts 136 * which use the first level to represent user_id. */ 137 PERM_LEGACY_PRE_ROOT, 138 /* This node is "/" */ 139 PERM_ROOT, 140 /* This node is "/Android" */ 141 PERM_ANDROID, 142 /* This node is "/Android/data" */ 143 PERM_ANDROID_DATA, 144 /* This node is "/Android/obb" */ 145 PERM_ANDROID_OBB, 146 /* This node is "/Android/media" */ 147 PERM_ANDROID_MEDIA, 148 /* This node is "/Android/user" */ 149 PERM_ANDROID_USER, 150 } perm_t; 151 152 /* Permissions structure to derive */ 153 typedef enum { 154 DERIVE_NONE, 155 DERIVE_LEGACY, 156 DERIVE_UNIFIED, 157 } derive_t; 158 159 struct handle { 160 int fd; 161 }; 162 163 struct dirhandle { 164 DIR *d; 165 }; 166 167 struct node { 168 __u32 refcount; 169 __u64 nid; 170 __u64 gen; 171 /* 172 * The inode number for this FUSE node. Note that this isn't stable across 173 * multiple invocations of the FUSE daemon. 174 */ 175 __u32 ino; 176 177 /* State derived based on current position in hierarchy. */ 178 perm_t perm; 179 userid_t userid; 180 uid_t uid; 181 gid_t gid; 182 mode_t mode; 183 184 struct node *next; /* per-dir sibling list */ 185 struct node *child; /* first contained file by this dir */ 186 struct node *parent; /* containing directory */ 187 188 size_t namelen; 189 char *name; 190 /* If non-null, this is the real name of the file in the underlying storage. 191 * This may differ from the field "name" only by case. 192 * strlen(actual_name) will always equal strlen(name), so it is safe to use 193 * namelen for both fields. 194 */ 195 char *actual_name; 196 197 /* If non-null, an exact underlying path that should be grafted into this 198 * position. Used to support things like OBB. */ 199 char* graft_path; 200 size_t graft_pathlen; 201 }; 202 203 static int str_hash(void *key) { 204 return hashmapHash(key, strlen(key)); 205 } 206 207 /** Test if two string keys are equal ignoring case */ 208 static bool str_icase_equals(void *keyA, void *keyB) { 209 return strcasecmp(keyA, keyB) == 0; 210 } 211 212 static int int_hash(void *key) { 213 return (int) (uintptr_t) key; 214 } 215 216 static bool int_equals(void *keyA, void *keyB) { 217 return keyA == keyB; 218 } 219 220 /* Global data structure shared by all fuse handlers. */ 221 struct fuse { 222 pthread_mutex_t lock; 223 224 __u64 next_generation; 225 int fd; 226 derive_t derive; 227 bool split_perms; 228 gid_t write_gid; 229 struct node root; 230 char obbpath[PATH_MAX]; 231 232 /* Used to allocate unique inode numbers for fuse nodes. We use 233 * a simple counter based scheme where inode numbers from deleted 234 * nodes aren't reused. Note that inode allocations are not stable 235 * across multiple invocation of the sdcard daemon, but that shouldn't 236 * be a huge problem in practice. 237 * 238 * Note that we restrict inodes to 32 bit unsigned integers to prevent 239 * truncation on 32 bit processes when unsigned long long stat.st_ino is 240 * assigned to an unsigned long ino_t type in an LP32 process. 241 * 242 * Also note that fuse_attr and fuse_dirent inode values are 64 bits wide 243 * on both LP32 and LP64, but the fuse kernel code doesn't squash 64 bit 244 * inode numbers into 32 bit values on 64 bit kernels (see fuse_squash_ino 245 * in fs/fuse/inode.c). 246 * 247 * Accesses must be guarded by |lock|. 248 */ 249 __u32 inode_ctr; 250 251 Hashmap* package_to_appid; 252 Hashmap* appid_with_rw; 253 }; 254 255 /* Private data used by a single fuse handler. */ 256 struct fuse_handler { 257 struct fuse* fuse; 258 int token; 259 260 /* To save memory, we never use the contents of the request buffer and the read 261 * buffer at the same time. This allows us to share the underlying storage. */ 262 union { 263 __u8 request_buffer[MAX_REQUEST_SIZE]; 264 __u8 read_buffer[MAX_READ + PAGESIZE]; 265 }; 266 }; 267 268 static inline void *id_to_ptr(__u64 nid) 269 { 270 return (void *) (uintptr_t) nid; 271 } 272 273 static inline __u64 ptr_to_id(void *ptr) 274 { 275 return (__u64) (uintptr_t) ptr; 276 } 277 278 static void acquire_node_locked(struct node* node) 279 { 280 node->refcount++; 281 TRACE("ACQUIRE %p (%s) rc=%d\n", node, node->name, node->refcount); 282 } 283 284 static void remove_node_from_parent_locked(struct node* node); 285 286 static void release_node_locked(struct node* node) 287 { 288 TRACE("RELEASE %p (%s) rc=%d\n", node, node->name, node->refcount); 289 if (node->refcount > 0) { 290 node->refcount--; 291 if (!node->refcount) { 292 TRACE("DESTROY %p (%s)\n", node, node->name); 293 remove_node_from_parent_locked(node); 294 295 /* TODO: remove debugging - poison memory */ 296 memset(node->name, 0xef, node->namelen); 297 free(node->name); 298 free(node->actual_name); 299 memset(node, 0xfc, sizeof(*node)); 300 free(node); 301 } 302 } else { 303 ERROR("Zero refcnt %p\n", node); 304 } 305 } 306 307 static void add_node_to_parent_locked(struct node *node, struct node *parent) { 308 node->parent = parent; 309 node->next = parent->child; 310 parent->child = node; 311 acquire_node_locked(parent); 312 } 313 314 static void remove_node_from_parent_locked(struct node* node) 315 { 316 if (node->parent) { 317 if (node->parent->child == node) { 318 node->parent->child = node->parent->child->next; 319 } else { 320 struct node *node2; 321 node2 = node->parent->child; 322 while (node2->next != node) 323 node2 = node2->next; 324 node2->next = node->next; 325 } 326 release_node_locked(node->parent); 327 node->parent = NULL; 328 node->next = NULL; 329 } 330 } 331 332 /* Gets the absolute path to a node into the provided buffer. 333 * 334 * Populates 'buf' with the path and returns the length of the path on success, 335 * or returns -1 if the path is too long for the provided buffer. 336 */ 337 static ssize_t get_node_path_locked(struct node* node, char* buf, size_t bufsize) { 338 const char* name; 339 size_t namelen; 340 if (node->graft_path) { 341 name = node->graft_path; 342 namelen = node->graft_pathlen; 343 } else if (node->actual_name) { 344 name = node->actual_name; 345 namelen = node->namelen; 346 } else { 347 name = node->name; 348 namelen = node->namelen; 349 } 350 351 if (bufsize < namelen + 1) { 352 return -1; 353 } 354 355 ssize_t pathlen = 0; 356 if (node->parent && node->graft_path == NULL) { 357 pathlen = get_node_path_locked(node->parent, buf, bufsize - namelen - 2); 358 if (pathlen < 0) { 359 return -1; 360 } 361 buf[pathlen++] = '/'; 362 } 363 364 memcpy(buf + pathlen, name, namelen + 1); /* include trailing \0 */ 365 return pathlen + namelen; 366 } 367 368 /* Finds the absolute path of a file within a given directory. 369 * Performs a case-insensitive search for the file and sets the buffer to the path 370 * of the first matching file. If 'search' is zero or if no match is found, sets 371 * the buffer to the path that the file would have, assuming the name were case-sensitive. 372 * 373 * Populates 'buf' with the path and returns the actual name (within 'buf') on success, 374 * or returns NULL if the path is too long for the provided buffer. 375 */ 376 static char* find_file_within(const char* path, const char* name, 377 char* buf, size_t bufsize, int search) 378 { 379 size_t pathlen = strlen(path); 380 size_t namelen = strlen(name); 381 size_t childlen = pathlen + namelen + 1; 382 char* actual; 383 384 if (bufsize <= childlen) { 385 return NULL; 386 } 387 388 memcpy(buf, path, pathlen); 389 buf[pathlen] = '/'; 390 actual = buf + pathlen + 1; 391 memcpy(actual, name, namelen + 1); 392 393 if (search && access(buf, F_OK)) { 394 struct dirent* entry; 395 DIR* dir = opendir(path); 396 if (!dir) { 397 ERROR("opendir %s failed: %s\n", path, strerror(errno)); 398 return actual; 399 } 400 while ((entry = readdir(dir))) { 401 if (!strcasecmp(entry->d_name, name)) { 402 /* we have a match - replace the name, don't need to copy the null again */ 403 memcpy(actual, entry->d_name, namelen); 404 break; 405 } 406 } 407 closedir(dir); 408 } 409 return actual; 410 } 411 412 static void attr_from_stat(struct fuse_attr *attr, const struct stat *s, const struct node* node) 413 { 414 attr->ino = node->ino; 415 attr->size = s->st_size; 416 attr->blocks = s->st_blocks; 417 attr->atime = s->st_atime; 418 attr->mtime = s->st_mtime; 419 attr->ctime = s->st_ctime; 420 attr->atimensec = s->st_atime_nsec; 421 attr->mtimensec = s->st_mtime_nsec; 422 attr->ctimensec = s->st_ctime_nsec; 423 attr->mode = s->st_mode; 424 attr->nlink = s->st_nlink; 425 426 attr->uid = node->uid; 427 attr->gid = node->gid; 428 429 /* Filter requested mode based on underlying file, and 430 * pass through file type. */ 431 int owner_mode = s->st_mode & 0700; 432 int filtered_mode = node->mode & (owner_mode | (owner_mode >> 3) | (owner_mode >> 6)); 433 attr->mode = (attr->mode & S_IFMT) | filtered_mode; 434 } 435 436 static int touch(char* path, mode_t mode) { 437 int fd = open(path, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW, mode); 438 if (fd == -1) { 439 if (errno == EEXIST) { 440 return 0; 441 } else { 442 ERROR("Failed to open(%s): %s\n", path, strerror(errno)); 443 return -1; 444 } 445 } 446 close(fd); 447 return 0; 448 } 449 450 static void derive_permissions_locked(struct fuse* fuse, struct node *parent, 451 struct node *node) { 452 appid_t appid; 453 454 /* By default, each node inherits from its parent */ 455 node->perm = PERM_INHERIT; 456 node->userid = parent->userid; 457 node->uid = parent->uid; 458 node->gid = parent->gid; 459 node->mode = parent->mode; 460 461 if (fuse->derive == DERIVE_NONE) { 462 return; 463 } 464 465 /* Derive custom permissions based on parent and current node */ 466 switch (parent->perm) { 467 case PERM_INHERIT: 468 /* Already inherited above */ 469 break; 470 case PERM_LEGACY_PRE_ROOT: 471 /* Legacy internal layout places users at top level */ 472 node->perm = PERM_ROOT; 473 node->userid = strtoul(node->name, NULL, 10); 474 break; 475 case PERM_ROOT: 476 /* Assume masked off by default. */ 477 node->mode = 0770; 478 if (!strcasecmp(node->name, "Android")) { 479 /* App-specific directories inside; let anyone traverse */ 480 node->perm = PERM_ANDROID; 481 node->mode = 0771; 482 } else if (fuse->split_perms) { 483 if (!strcasecmp(node->name, "DCIM") 484 || !strcasecmp(node->name, "Pictures")) { 485 node->gid = AID_SDCARD_PICS; 486 } else if (!strcasecmp(node->name, "Alarms") 487 || !strcasecmp(node->name, "Movies") 488 || !strcasecmp(node->name, "Music") 489 || !strcasecmp(node->name, "Notifications") 490 || !strcasecmp(node->name, "Podcasts") 491 || !strcasecmp(node->name, "Ringtones")) { 492 node->gid = AID_SDCARD_AV; 493 } 494 } 495 break; 496 case PERM_ANDROID: 497 if (!strcasecmp(node->name, "data")) { 498 /* App-specific directories inside; let anyone traverse */ 499 node->perm = PERM_ANDROID_DATA; 500 node->mode = 0771; 501 } else if (!strcasecmp(node->name, "obb")) { 502 /* App-specific directories inside; let anyone traverse */ 503 node->perm = PERM_ANDROID_OBB; 504 node->mode = 0771; 505 /* Single OBB directory is always shared */ 506 node->graft_path = fuse->obbpath; 507 node->graft_pathlen = strlen(fuse->obbpath); 508 } else if (!strcasecmp(node->name, "media")) { 509 /* App-specific directories inside; let anyone traverse */ 510 node->perm = PERM_ANDROID_MEDIA; 511 node->mode = 0771; 512 } else if (!strcasecmp(node->name, "user")) { 513 /* User directories must only be accessible to system, protected 514 * by sdcard_all. Zygote will bind mount the appropriate user- 515 * specific path. */ 516 node->perm = PERM_ANDROID_USER; 517 node->gid = AID_SDCARD_ALL; 518 node->mode = 0770; 519 } 520 break; 521 case PERM_ANDROID_DATA: 522 case PERM_ANDROID_OBB: 523 case PERM_ANDROID_MEDIA: 524 appid = (appid_t) (uintptr_t) hashmapGet(fuse->package_to_appid, node->name); 525 if (appid != 0) { 526 node->uid = multiuser_get_uid(parent->userid, appid); 527 } 528 node->mode = 0770; 529 break; 530 case PERM_ANDROID_USER: 531 /* Root of a secondary user */ 532 node->perm = PERM_ROOT; 533 node->userid = strtoul(node->name, NULL, 10); 534 node->gid = AID_SDCARD_R; 535 node->mode = 0771; 536 break; 537 } 538 } 539 540 /* Return if the calling UID holds sdcard_rw. */ 541 static bool get_caller_has_rw_locked(struct fuse* fuse, const struct fuse_in_header *hdr) { 542 /* No additional permissions enforcement */ 543 if (fuse->derive == DERIVE_NONE) { 544 return true; 545 } 546 547 appid_t appid = multiuser_get_app_id(hdr->uid); 548 return hashmapContainsKey(fuse->appid_with_rw, (void*) (uintptr_t) appid); 549 } 550 551 /* Kernel has already enforced everything we returned through 552 * derive_permissions_locked(), so this is used to lock down access 553 * even further, such as enforcing that apps hold sdcard_rw. */ 554 static bool check_caller_access_to_name(struct fuse* fuse, 555 const struct fuse_in_header *hdr, const struct node* parent_node, 556 const char* name, int mode, bool has_rw) { 557 /* Always block security-sensitive files at root */ 558 if (parent_node && parent_node->perm == PERM_ROOT) { 559 if (!strcasecmp(name, "autorun.inf") 560 || !strcasecmp(name, ".android_secure") 561 || !strcasecmp(name, "android_secure")) { 562 return false; 563 } 564 } 565 566 /* No additional permissions enforcement */ 567 if (fuse->derive == DERIVE_NONE) { 568 return true; 569 } 570 571 /* Root always has access; access for any other UIDs should always 572 * be controlled through packages.list. */ 573 if (hdr->uid == 0) { 574 return true; 575 } 576 577 /* If asking to write, verify that caller either owns the 578 * parent or holds sdcard_rw. */ 579 if (mode & W_OK) { 580 if (parent_node && hdr->uid == parent_node->uid) { 581 return true; 582 } 583 584 return has_rw; 585 } 586 587 /* No extra permissions to enforce */ 588 return true; 589 } 590 591 static bool check_caller_access_to_node(struct fuse* fuse, 592 const struct fuse_in_header *hdr, const struct node* node, int mode, bool has_rw) { 593 return check_caller_access_to_name(fuse, hdr, node->parent, node->name, mode, has_rw); 594 } 595 596 struct node *create_node_locked(struct fuse* fuse, 597 struct node *parent, const char *name, const char* actual_name) 598 { 599 struct node *node; 600 size_t namelen = strlen(name); 601 602 // Detect overflows in the inode counter. "4 billion nodes should be enough 603 // for everybody". 604 if (fuse->inode_ctr == 0) { 605 ERROR("No more inode numbers available"); 606 return NULL; 607 } 608 609 node = calloc(1, sizeof(struct node)); 610 if (!node) { 611 return NULL; 612 } 613 node->name = malloc(namelen + 1); 614 if (!node->name) { 615 free(node); 616 return NULL; 617 } 618 memcpy(node->name, name, namelen + 1); 619 if (strcmp(name, actual_name)) { 620 node->actual_name = malloc(namelen + 1); 621 if (!node->actual_name) { 622 free(node->name); 623 free(node); 624 return NULL; 625 } 626 memcpy(node->actual_name, actual_name, namelen + 1); 627 } 628 node->namelen = namelen; 629 node->nid = ptr_to_id(node); 630 node->ino = fuse->inode_ctr++; 631 node->gen = fuse->next_generation++; 632 633 derive_permissions_locked(fuse, parent, node); 634 acquire_node_locked(node); 635 add_node_to_parent_locked(node, parent); 636 return node; 637 } 638 639 static int rename_node_locked(struct node *node, const char *name, 640 const char* actual_name) 641 { 642 size_t namelen = strlen(name); 643 int need_actual_name = strcmp(name, actual_name); 644 645 /* make the storage bigger without actually changing the name 646 * in case an error occurs part way */ 647 if (namelen > node->namelen) { 648 char* new_name = realloc(node->name, namelen + 1); 649 if (!new_name) { 650 return -ENOMEM; 651 } 652 node->name = new_name; 653 if (need_actual_name && node->actual_name) { 654 char* new_actual_name = realloc(node->actual_name, namelen + 1); 655 if (!new_actual_name) { 656 return -ENOMEM; 657 } 658 node->actual_name = new_actual_name; 659 } 660 } 661 662 /* update the name, taking care to allocate storage before overwriting the old name */ 663 if (need_actual_name) { 664 if (!node->actual_name) { 665 node->actual_name = malloc(namelen + 1); 666 if (!node->actual_name) { 667 return -ENOMEM; 668 } 669 } 670 memcpy(node->actual_name, actual_name, namelen + 1); 671 } else { 672 free(node->actual_name); 673 node->actual_name = NULL; 674 } 675 memcpy(node->name, name, namelen + 1); 676 node->namelen = namelen; 677 return 0; 678 } 679 680 static struct node *lookup_node_by_id_locked(struct fuse *fuse, __u64 nid) 681 { 682 if (nid == FUSE_ROOT_ID) { 683 return &fuse->root; 684 } else { 685 return id_to_ptr(nid); 686 } 687 } 688 689 static struct node* lookup_node_and_path_by_id_locked(struct fuse* fuse, __u64 nid, 690 char* buf, size_t bufsize) 691 { 692 struct node* node = lookup_node_by_id_locked(fuse, nid); 693 if (node && get_node_path_locked(node, buf, bufsize) < 0) { 694 node = NULL; 695 } 696 return node; 697 } 698 699 static struct node *lookup_child_by_name_locked(struct node *node, const char *name) 700 { 701 for (node = node->child; node; node = node->next) { 702 /* use exact string comparison, nodes that differ by case 703 * must be considered distinct even if they refer to the same 704 * underlying file as otherwise operations such as "mv x x" 705 * will not work because the source and target nodes are the same. */ 706 if (!strcmp(name, node->name)) { 707 return node; 708 } 709 } 710 return 0; 711 } 712 713 static struct node* acquire_or_create_child_locked( 714 struct fuse* fuse, struct node* parent, 715 const char* name, const char* actual_name) 716 { 717 struct node* child = lookup_child_by_name_locked(parent, name); 718 if (child) { 719 acquire_node_locked(child); 720 } else { 721 child = create_node_locked(fuse, parent, name, actual_name); 722 } 723 return child; 724 } 725 726 static void fuse_init(struct fuse *fuse, int fd, const char *source_path, 727 gid_t write_gid, derive_t derive, bool split_perms) { 728 pthread_mutex_init(&fuse->lock, NULL); 729 730 fuse->fd = fd; 731 fuse->next_generation = 0; 732 fuse->derive = derive; 733 fuse->split_perms = split_perms; 734 fuse->write_gid = write_gid; 735 fuse->inode_ctr = 1; 736 737 memset(&fuse->root, 0, sizeof(fuse->root)); 738 fuse->root.nid = FUSE_ROOT_ID; /* 1 */ 739 fuse->root.refcount = 2; 740 fuse->root.namelen = strlen(source_path); 741 fuse->root.name = strdup(source_path); 742 fuse->root.userid = 0; 743 fuse->root.uid = AID_ROOT; 744 745 /* Set up root node for various modes of operation */ 746 switch (derive) { 747 case DERIVE_NONE: 748 /* Traditional behavior that treats entire device as being accessible 749 * to sdcard_rw, and no permissions are derived. */ 750 fuse->root.perm = PERM_ROOT; 751 fuse->root.mode = 0775; 752 fuse->root.gid = AID_SDCARD_RW; 753 break; 754 case DERIVE_LEGACY: 755 /* Legacy behavior used to support internal multiuser layout which 756 * places user_id at the top directory level, with the actual roots 757 * just below that. Shared OBB path is also at top level. */ 758 fuse->root.perm = PERM_LEGACY_PRE_ROOT; 759 fuse->root.mode = 0771; 760 fuse->root.gid = AID_SDCARD_R; 761 fuse->package_to_appid = hashmapCreate(256, str_hash, str_icase_equals); 762 fuse->appid_with_rw = hashmapCreate(128, int_hash, int_equals); 763 snprintf(fuse->obbpath, sizeof(fuse->obbpath), "%s/obb", source_path); 764 fs_prepare_dir(fuse->obbpath, 0775, getuid(), getgid()); 765 break; 766 case DERIVE_UNIFIED: 767 /* Unified multiuser layout which places secondary user_id under 768 * /Android/user and shared OBB path under /Android/obb. */ 769 fuse->root.perm = PERM_ROOT; 770 fuse->root.mode = 0771; 771 fuse->root.gid = AID_SDCARD_R; 772 fuse->package_to_appid = hashmapCreate(256, str_hash, str_icase_equals); 773 fuse->appid_with_rw = hashmapCreate(128, int_hash, int_equals); 774 snprintf(fuse->obbpath, sizeof(fuse->obbpath), "%s/Android/obb", source_path); 775 break; 776 } 777 } 778 779 static void fuse_status(struct fuse *fuse, __u64 unique, int err) 780 { 781 struct fuse_out_header hdr; 782 hdr.len = sizeof(hdr); 783 hdr.error = err; 784 hdr.unique = unique; 785 write(fuse->fd, &hdr, sizeof(hdr)); 786 } 787 788 static void fuse_reply(struct fuse *fuse, __u64 unique, void *data, int len) 789 { 790 struct fuse_out_header hdr; 791 struct iovec vec[2]; 792 int res; 793 794 hdr.len = len + sizeof(hdr); 795 hdr.error = 0; 796 hdr.unique = unique; 797 798 vec[0].iov_base = &hdr; 799 vec[0].iov_len = sizeof(hdr); 800 vec[1].iov_base = data; 801 vec[1].iov_len = len; 802 803 res = writev(fuse->fd, vec, 2); 804 if (res < 0) { 805 ERROR("*** REPLY FAILED *** %d\n", errno); 806 } 807 } 808 809 static int fuse_reply_entry(struct fuse* fuse, __u64 unique, 810 struct node* parent, const char* name, const char* actual_name, 811 const char* path) 812 { 813 struct node* node; 814 struct fuse_entry_out out; 815 struct stat s; 816 817 if (lstat(path, &s) < 0) { 818 return -errno; 819 } 820 821 pthread_mutex_lock(&fuse->lock); 822 node = acquire_or_create_child_locked(fuse, parent, name, actual_name); 823 if (!node) { 824 pthread_mutex_unlock(&fuse->lock); 825 return -ENOMEM; 826 } 827 memset(&out, 0, sizeof(out)); 828 attr_from_stat(&out.attr, &s, node); 829 out.attr_valid = 10; 830 out.entry_valid = 10; 831 out.nodeid = node->nid; 832 out.generation = node->gen; 833 pthread_mutex_unlock(&fuse->lock); 834 fuse_reply(fuse, unique, &out, sizeof(out)); 835 return NO_STATUS; 836 } 837 838 static int fuse_reply_attr(struct fuse* fuse, __u64 unique, const struct node* node, 839 const char* path) 840 { 841 struct fuse_attr_out out; 842 struct stat s; 843 844 if (lstat(path, &s) < 0) { 845 return -errno; 846 } 847 memset(&out, 0, sizeof(out)); 848 attr_from_stat(&out.attr, &s, node); 849 out.attr_valid = 10; 850 fuse_reply(fuse, unique, &out, sizeof(out)); 851 return NO_STATUS; 852 } 853 854 static int handle_lookup(struct fuse* fuse, struct fuse_handler* handler, 855 const struct fuse_in_header *hdr, const char* name) 856 { 857 struct node* parent_node; 858 char parent_path[PATH_MAX]; 859 char child_path[PATH_MAX]; 860 const char* actual_name; 861 862 pthread_mutex_lock(&fuse->lock); 863 parent_node = lookup_node_and_path_by_id_locked(fuse, hdr->nodeid, 864 parent_path, sizeof(parent_path)); 865 TRACE("[%d] LOOKUP %s @ %"PRIx64" (%s)\n", handler->token, name, hdr->nodeid, 866 parent_node ? parent_node->name : "?"); 867 pthread_mutex_unlock(&fuse->lock); 868 869 if (!parent_node || !(actual_name = find_file_within(parent_path, name, 870 child_path, sizeof(child_path), 1))) { 871 return -ENOENT; 872 } 873 if (!check_caller_access_to_name(fuse, hdr, parent_node, name, R_OK, false)) { 874 return -EACCES; 875 } 876 877 return fuse_reply_entry(fuse, hdr->unique, parent_node, name, actual_name, child_path); 878 } 879 880 static int handle_forget(struct fuse* fuse, struct fuse_handler* handler, 881 const struct fuse_in_header *hdr, const struct fuse_forget_in *req) 882 { 883 struct node* node; 884 885 pthread_mutex_lock(&fuse->lock); 886 node = lookup_node_by_id_locked(fuse, hdr->nodeid); 887 TRACE("[%d] FORGET #%"PRIu64" @ %"PRIx64" (%s)\n", handler->token, req->nlookup, 888 hdr->nodeid, node ? node->name : "?"); 889 if (node) { 890 __u64 n = req->nlookup; 891 while (n--) { 892 release_node_locked(node); 893 } 894 } 895 pthread_mutex_unlock(&fuse->lock); 896 return NO_STATUS; /* no reply */ 897 } 898 899 static int handle_getattr(struct fuse* fuse, struct fuse_handler* handler, 900 const struct fuse_in_header *hdr, const struct fuse_getattr_in *req) 901 { 902 struct node* node; 903 char path[PATH_MAX]; 904 905 pthread_mutex_lock(&fuse->lock); 906 node = lookup_node_and_path_by_id_locked(fuse, hdr->nodeid, path, sizeof(path)); 907 TRACE("[%d] GETATTR flags=%x fh=%"PRIx64" @ %"PRIx64" (%s)\n", handler->token, 908 req->getattr_flags, req->fh, hdr->nodeid, node ? node->name : "?"); 909 pthread_mutex_unlock(&fuse->lock); 910 911 if (!node) { 912 return -ENOENT; 913 } 914 if (!check_caller_access_to_node(fuse, hdr, node, R_OK, false)) { 915 return -EACCES; 916 } 917 918 return fuse_reply_attr(fuse, hdr->unique, node, path); 919 } 920 921 static int handle_setattr(struct fuse* fuse, struct fuse_handler* handler, 922 const struct fuse_in_header *hdr, const struct fuse_setattr_in *req) 923 { 924 bool has_rw; 925 struct node* node; 926 char path[PATH_MAX]; 927 struct timespec times[2]; 928 929 pthread_mutex_lock(&fuse->lock); 930 has_rw = get_caller_has_rw_locked(fuse, hdr); 931 node = lookup_node_and_path_by_id_locked(fuse, hdr->nodeid, path, sizeof(path)); 932 TRACE("[%d] SETATTR fh=%"PRIx64" valid=%x @ %"PRIx64" (%s)\n", handler->token, 933 req->fh, req->valid, hdr->nodeid, node ? node->name : "?"); 934 pthread_mutex_unlock(&fuse->lock); 935 936 if (!node) { 937 return -ENOENT; 938 } 939 if (!check_caller_access_to_node(fuse, hdr, node, W_OK, has_rw)) { 940 return -EACCES; 941 } 942 943 /* XXX: incomplete implementation on purpose. 944 * chmod/chown should NEVER be implemented.*/ 945 946 if ((req->valid & FATTR_SIZE) && truncate64(path, req->size) < 0) { 947 return -errno; 948 } 949 950 /* Handle changing atime and mtime. If FATTR_ATIME_and FATTR_ATIME_NOW 951 * are both set, then set it to the current time. Else, set it to the 952 * time specified in the request. Same goes for mtime. Use utimensat(2) 953 * as it allows ATIME and MTIME to be changed independently, and has 954 * nanosecond resolution which fuse also has. 955 */ 956 if (req->valid & (FATTR_ATIME | FATTR_MTIME)) { 957 times[0].tv_nsec = UTIME_OMIT; 958 times[1].tv_nsec = UTIME_OMIT; 959 if (req->valid & FATTR_ATIME) { 960 if (req->valid & FATTR_ATIME_NOW) { 961 times[0].tv_nsec = UTIME_NOW; 962 } else { 963 times[0].tv_sec = req->atime; 964 times[0].tv_nsec = req->atimensec; 965 } 966 } 967 if (req->valid & FATTR_MTIME) { 968 if (req->valid & FATTR_MTIME_NOW) { 969 times[1].tv_nsec = UTIME_NOW; 970 } else { 971 times[1].tv_sec = req->mtime; 972 times[1].tv_nsec = req->mtimensec; 973 } 974 } 975 TRACE("[%d] Calling utimensat on %s with atime %ld, mtime=%ld\n", 976 handler->token, path, times[0].tv_sec, times[1].tv_sec); 977 if (utimensat(-1, path, times, 0) < 0) { 978 return -errno; 979 } 980 } 981 return fuse_reply_attr(fuse, hdr->unique, node, path); 982 } 983 984 static int handle_mknod(struct fuse* fuse, struct fuse_handler* handler, 985 const struct fuse_in_header* hdr, const struct fuse_mknod_in* req, const char* name) 986 { 987 bool has_rw; 988 struct node* parent_node; 989 char parent_path[PATH_MAX]; 990 char child_path[PATH_MAX]; 991 const char* actual_name; 992 993 pthread_mutex_lock(&fuse->lock); 994 has_rw = get_caller_has_rw_locked(fuse, hdr); 995 parent_node = lookup_node_and_path_by_id_locked(fuse, hdr->nodeid, 996 parent_path, sizeof(parent_path)); 997 TRACE("[%d] MKNOD %s 0%o @ %"PRIx64" (%s)\n", handler->token, 998 name, req->mode, hdr->nodeid, parent_node ? parent_node->name : "?"); 999 pthread_mutex_unlock(&fuse->lock); 1000 1001 if (!parent_node || !(actual_name = find_file_within(parent_path, name, 1002 child_path, sizeof(child_path), 1))) { 1003 return -ENOENT; 1004 } 1005 if (!check_caller_access_to_name(fuse, hdr, parent_node, name, W_OK, has_rw)) { 1006 return -EACCES; 1007 } 1008 __u32 mode = (req->mode & (~0777)) | 0664; 1009 if (mknod(child_path, mode, req->rdev) < 0) { 1010 return -errno; 1011 } 1012 return fuse_reply_entry(fuse, hdr->unique, parent_node, name, actual_name, child_path); 1013 } 1014 1015 static int handle_mkdir(struct fuse* fuse, struct fuse_handler* handler, 1016 const struct fuse_in_header* hdr, const struct fuse_mkdir_in* req, const char* name) 1017 { 1018 bool has_rw; 1019 struct node* parent_node; 1020 char parent_path[PATH_MAX]; 1021 char child_path[PATH_MAX]; 1022 const char* actual_name; 1023 1024 pthread_mutex_lock(&fuse->lock); 1025 has_rw = get_caller_has_rw_locked(fuse, hdr); 1026 parent_node = lookup_node_and_path_by_id_locked(fuse, hdr->nodeid, 1027 parent_path, sizeof(parent_path)); 1028 TRACE("[%d] MKDIR %s 0%o @ %"PRIx64" (%s)\n", handler->token, 1029 name, req->mode, hdr->nodeid, parent_node ? parent_node->name : "?"); 1030 pthread_mutex_unlock(&fuse->lock); 1031 1032 if (!parent_node || !(actual_name = find_file_within(parent_path, name, 1033 child_path, sizeof(child_path), 1))) { 1034 return -ENOENT; 1035 } 1036 if (!check_caller_access_to_name(fuse, hdr, parent_node, name, W_OK, has_rw)) { 1037 return -EACCES; 1038 } 1039 __u32 mode = (req->mode & (~0777)) | 0775; 1040 if (mkdir(child_path, mode) < 0) { 1041 return -errno; 1042 } 1043 1044 /* When creating /Android/data and /Android/obb, mark them as .nomedia */ 1045 if (parent_node->perm == PERM_ANDROID && !strcasecmp(name, "data")) { 1046 char nomedia[PATH_MAX]; 1047 snprintf(nomedia, PATH_MAX, "%s/.nomedia", child_path); 1048 if (touch(nomedia, 0664) != 0) { 1049 ERROR("Failed to touch(%s): %s\n", nomedia, strerror(errno)); 1050 return -ENOENT; 1051 } 1052 } 1053 if (parent_node->perm == PERM_ANDROID && !strcasecmp(name, "obb")) { 1054 char nomedia[PATH_MAX]; 1055 snprintf(nomedia, PATH_MAX, "%s/.nomedia", fuse->obbpath); 1056 if (touch(nomedia, 0664) != 0) { 1057 ERROR("Failed to touch(%s): %s\n", nomedia, strerror(errno)); 1058 return -ENOENT; 1059 } 1060 } 1061 1062 return fuse_reply_entry(fuse, hdr->unique, parent_node, name, actual_name, child_path); 1063 } 1064 1065 static int handle_unlink(struct fuse* fuse, struct fuse_handler* handler, 1066 const struct fuse_in_header* hdr, const char* name) 1067 { 1068 bool has_rw; 1069 struct node* parent_node; 1070 char parent_path[PATH_MAX]; 1071 char child_path[PATH_MAX]; 1072 1073 pthread_mutex_lock(&fuse->lock); 1074 has_rw = get_caller_has_rw_locked(fuse, hdr); 1075 parent_node = lookup_node_and_path_by_id_locked(fuse, hdr->nodeid, 1076 parent_path, sizeof(parent_path)); 1077 TRACE("[%d] UNLINK %s @ %"PRIx64" (%s)\n", handler->token, 1078 name, hdr->nodeid, parent_node ? parent_node->name : "?"); 1079 pthread_mutex_unlock(&fuse->lock); 1080 1081 if (!parent_node || !find_file_within(parent_path, name, 1082 child_path, sizeof(child_path), 1)) { 1083 return -ENOENT; 1084 } 1085 if (!check_caller_access_to_name(fuse, hdr, parent_node, name, W_OK, has_rw)) { 1086 return -EACCES; 1087 } 1088 if (unlink(child_path) < 0) { 1089 return -errno; 1090 } 1091 return 0; 1092 } 1093 1094 static int handle_rmdir(struct fuse* fuse, struct fuse_handler* handler, 1095 const struct fuse_in_header* hdr, const char* name) 1096 { 1097 bool has_rw; 1098 struct node* parent_node; 1099 char parent_path[PATH_MAX]; 1100 char child_path[PATH_MAX]; 1101 1102 pthread_mutex_lock(&fuse->lock); 1103 has_rw = get_caller_has_rw_locked(fuse, hdr); 1104 parent_node = lookup_node_and_path_by_id_locked(fuse, hdr->nodeid, 1105 parent_path, sizeof(parent_path)); 1106 TRACE("[%d] RMDIR %s @ %"PRIx64" (%s)\n", handler->token, 1107 name, hdr->nodeid, parent_node ? parent_node->name : "?"); 1108 pthread_mutex_unlock(&fuse->lock); 1109 1110 if (!parent_node || !find_file_within(parent_path, name, 1111 child_path, sizeof(child_path), 1)) { 1112 return -ENOENT; 1113 } 1114 if (!check_caller_access_to_name(fuse, hdr, parent_node, name, W_OK, has_rw)) { 1115 return -EACCES; 1116 } 1117 if (rmdir(child_path) < 0) { 1118 return -errno; 1119 } 1120 return 0; 1121 } 1122 1123 static int handle_rename(struct fuse* fuse, struct fuse_handler* handler, 1124 const struct fuse_in_header* hdr, const struct fuse_rename_in* req, 1125 const char* old_name, const char* new_name) 1126 { 1127 bool has_rw; 1128 struct node* old_parent_node; 1129 struct node* new_parent_node; 1130 struct node* child_node; 1131 char old_parent_path[PATH_MAX]; 1132 char new_parent_path[PATH_MAX]; 1133 char old_child_path[PATH_MAX]; 1134 char new_child_path[PATH_MAX]; 1135 const char* new_actual_name; 1136 int res; 1137 1138 pthread_mutex_lock(&fuse->lock); 1139 has_rw = get_caller_has_rw_locked(fuse, hdr); 1140 old_parent_node = lookup_node_and_path_by_id_locked(fuse, hdr->nodeid, 1141 old_parent_path, sizeof(old_parent_path)); 1142 new_parent_node = lookup_node_and_path_by_id_locked(fuse, req->newdir, 1143 new_parent_path, sizeof(new_parent_path)); 1144 TRACE("[%d] RENAME %s->%s @ %"PRIx64" (%s) -> %"PRIx64" (%s)\n", handler->token, 1145 old_name, new_name, 1146 hdr->nodeid, old_parent_node ? old_parent_node->name : "?", 1147 req->newdir, new_parent_node ? new_parent_node->name : "?"); 1148 if (!old_parent_node || !new_parent_node) { 1149 res = -ENOENT; 1150 goto lookup_error; 1151 } 1152 if (!check_caller_access_to_name(fuse, hdr, old_parent_node, old_name, W_OK, has_rw)) { 1153 res = -EACCES; 1154 goto lookup_error; 1155 } 1156 if (!check_caller_access_to_name(fuse, hdr, new_parent_node, new_name, W_OK, has_rw)) { 1157 res = -EACCES; 1158 goto lookup_error; 1159 } 1160 child_node = lookup_child_by_name_locked(old_parent_node, old_name); 1161 if (!child_node || get_node_path_locked(child_node, 1162 old_child_path, sizeof(old_child_path)) < 0) { 1163 res = -ENOENT; 1164 goto lookup_error; 1165 } 1166 acquire_node_locked(child_node); 1167 pthread_mutex_unlock(&fuse->lock); 1168 1169 /* Special case for renaming a file where destination is same path 1170 * differing only by case. In this case we don't want to look for a case 1171 * insensitive match. This allows commands like "mv foo FOO" to work as expected. 1172 */ 1173 int search = old_parent_node != new_parent_node 1174 || strcasecmp(old_name, new_name); 1175 if (!(new_actual_name = find_file_within(new_parent_path, new_name, 1176 new_child_path, sizeof(new_child_path), search))) { 1177 res = -ENOENT; 1178 goto io_error; 1179 } 1180 1181 TRACE("[%d] RENAME %s->%s\n", handler->token, old_child_path, new_child_path); 1182 res = rename(old_child_path, new_child_path); 1183 if (res < 0) { 1184 res = -errno; 1185 goto io_error; 1186 } 1187 1188 pthread_mutex_lock(&fuse->lock); 1189 res = rename_node_locked(child_node, new_name, new_actual_name); 1190 if (!res) { 1191 remove_node_from_parent_locked(child_node); 1192 add_node_to_parent_locked(child_node, new_parent_node); 1193 } 1194 goto done; 1195 1196 io_error: 1197 pthread_mutex_lock(&fuse->lock); 1198 done: 1199 release_node_locked(child_node); 1200 lookup_error: 1201 pthread_mutex_unlock(&fuse->lock); 1202 return res; 1203 } 1204 1205 static int open_flags_to_access_mode(int open_flags) { 1206 if ((open_flags & O_ACCMODE) == O_RDONLY) { 1207 return R_OK; 1208 } else if ((open_flags & O_ACCMODE) == O_WRONLY) { 1209 return W_OK; 1210 } else { 1211 /* Probably O_RDRW, but treat as default to be safe */ 1212 return R_OK | W_OK; 1213 } 1214 } 1215 1216 static int handle_open(struct fuse* fuse, struct fuse_handler* handler, 1217 const struct fuse_in_header* hdr, const struct fuse_open_in* req) 1218 { 1219 bool has_rw; 1220 struct node* node; 1221 char path[PATH_MAX]; 1222 struct fuse_open_out out; 1223 struct handle *h; 1224 1225 pthread_mutex_lock(&fuse->lock); 1226 has_rw = get_caller_has_rw_locked(fuse, hdr); 1227 node = lookup_node_and_path_by_id_locked(fuse, hdr->nodeid, path, sizeof(path)); 1228 TRACE("[%d] OPEN 0%o @ %"PRIx64" (%s)\n", handler->token, 1229 req->flags, hdr->nodeid, node ? node->name : "?"); 1230 pthread_mutex_unlock(&fuse->lock); 1231 1232 if (!node) { 1233 return -ENOENT; 1234 } 1235 if (!check_caller_access_to_node(fuse, hdr, node, 1236 open_flags_to_access_mode(req->flags), has_rw)) { 1237 return -EACCES; 1238 } 1239 h = malloc(sizeof(*h)); 1240 if (!h) { 1241 return -ENOMEM; 1242 } 1243 TRACE("[%d] OPEN %s\n", handler->token, path); 1244 h->fd = open(path, req->flags); 1245 if (h->fd < 0) { 1246 free(h); 1247 return -errno; 1248 } 1249 out.fh = ptr_to_id(h); 1250 out.open_flags = 0; 1251 out.padding = 0; 1252 fuse_reply(fuse, hdr->unique, &out, sizeof(out)); 1253 return NO_STATUS; 1254 } 1255 1256 static int handle_read(struct fuse* fuse, struct fuse_handler* handler, 1257 const struct fuse_in_header* hdr, const struct fuse_read_in* req) 1258 { 1259 struct handle *h = id_to_ptr(req->fh); 1260 __u64 unique = hdr->unique; 1261 __u32 size = req->size; 1262 __u64 offset = req->offset; 1263 int res; 1264 __u8 *read_buffer = (__u8 *) ((uintptr_t)(handler->read_buffer + PAGESIZE) & ~((uintptr_t)PAGESIZE-1)); 1265 1266 /* Don't access any other fields of hdr or req beyond this point, the read buffer 1267 * overlaps the request buffer and will clobber data in the request. This 1268 * saves us 128KB per request handler thread at the cost of this scary comment. */ 1269 1270 TRACE("[%d] READ %p(%d) %u@%"PRIu64"\n", handler->token, 1271 h, h->fd, size, (uint64_t) offset); 1272 if (size > MAX_READ) { 1273 return -EINVAL; 1274 } 1275 res = pread64(h->fd, read_buffer, size, offset); 1276 if (res < 0) { 1277 return -errno; 1278 } 1279 fuse_reply(fuse, unique, read_buffer, res); 1280 return NO_STATUS; 1281 } 1282 1283 static int handle_write(struct fuse* fuse, struct fuse_handler* handler, 1284 const struct fuse_in_header* hdr, const struct fuse_write_in* req, 1285 const void* buffer) 1286 { 1287 struct fuse_write_out out; 1288 struct handle *h = id_to_ptr(req->fh); 1289 int res; 1290 __u8 aligned_buffer[req->size] __attribute__((__aligned__(PAGESIZE))); 1291 1292 if (req->flags & O_DIRECT) { 1293 memcpy(aligned_buffer, buffer, req->size); 1294 buffer = (const __u8*) aligned_buffer; 1295 } 1296 1297 TRACE("[%d] WRITE %p(%d) %u@%"PRIu64"\n", handler->token, 1298 h, h->fd, req->size, req->offset); 1299 res = pwrite64(h->fd, buffer, req->size, req->offset); 1300 if (res < 0) { 1301 return -errno; 1302 } 1303 out.size = res; 1304 fuse_reply(fuse, hdr->unique, &out, sizeof(out)); 1305 return NO_STATUS; 1306 } 1307 1308 static int handle_statfs(struct fuse* fuse, struct fuse_handler* handler, 1309 const struct fuse_in_header* hdr) 1310 { 1311 char path[PATH_MAX]; 1312 struct statfs stat; 1313 struct fuse_statfs_out out; 1314 int res; 1315 1316 pthread_mutex_lock(&fuse->lock); 1317 TRACE("[%d] STATFS\n", handler->token); 1318 res = get_node_path_locked(&fuse->root, path, sizeof(path)); 1319 pthread_mutex_unlock(&fuse->lock); 1320 if (res < 0) { 1321 return -ENOENT; 1322 } 1323 if (statfs(fuse->root.name, &stat) < 0) { 1324 return -errno; 1325 } 1326 memset(&out, 0, sizeof(out)); 1327 out.st.blocks = stat.f_blocks; 1328 out.st.bfree = stat.f_bfree; 1329 out.st.bavail = stat.f_bavail; 1330 out.st.files = stat.f_files; 1331 out.st.ffree = stat.f_ffree; 1332 out.st.bsize = stat.f_bsize; 1333 out.st.namelen = stat.f_namelen; 1334 out.st.frsize = stat.f_frsize; 1335 fuse_reply(fuse, hdr->unique, &out, sizeof(out)); 1336 return NO_STATUS; 1337 } 1338 1339 static int handle_release(struct fuse* fuse, struct fuse_handler* handler, 1340 const struct fuse_in_header* hdr, const struct fuse_release_in* req) 1341 { 1342 struct handle *h = id_to_ptr(req->fh); 1343 1344 TRACE("[%d] RELEASE %p(%d)\n", handler->token, h, h->fd); 1345 close(h->fd); 1346 free(h); 1347 return 0; 1348 } 1349 1350 static int handle_fsync(struct fuse* fuse, struct fuse_handler* handler, 1351 const struct fuse_in_header* hdr, const struct fuse_fsync_in* req) 1352 { 1353 bool is_dir = (hdr->opcode == FUSE_FSYNCDIR); 1354 bool is_data_sync = req->fsync_flags & 1; 1355 1356 int fd = -1; 1357 if (is_dir) { 1358 struct dirhandle *dh = id_to_ptr(req->fh); 1359 fd = dirfd(dh->d); 1360 } else { 1361 struct handle *h = id_to_ptr(req->fh); 1362 fd = h->fd; 1363 } 1364 1365 TRACE("[%d] %s %p(%d) is_data_sync=%d\n", handler->token, 1366 is_dir ? "FSYNCDIR" : "FSYNC", 1367 id_to_ptr(req->fh), fd, is_data_sync); 1368 int res = is_data_sync ? fdatasync(fd) : fsync(fd); 1369 if (res == -1) { 1370 return -errno; 1371 } 1372 return 0; 1373 } 1374 1375 static int handle_flush(struct fuse* fuse, struct fuse_handler* handler, 1376 const struct fuse_in_header* hdr) 1377 { 1378 TRACE("[%d] FLUSH\n", handler->token); 1379 return 0; 1380 } 1381 1382 static int handle_opendir(struct fuse* fuse, struct fuse_handler* handler, 1383 const struct fuse_in_header* hdr, const struct fuse_open_in* req) 1384 { 1385 struct node* node; 1386 char path[PATH_MAX]; 1387 struct fuse_open_out out; 1388 struct dirhandle *h; 1389 1390 pthread_mutex_lock(&fuse->lock); 1391 node = lookup_node_and_path_by_id_locked(fuse, hdr->nodeid, path, sizeof(path)); 1392 TRACE("[%d] OPENDIR @ %"PRIx64" (%s)\n", handler->token, 1393 hdr->nodeid, node ? node->name : "?"); 1394 pthread_mutex_unlock(&fuse->lock); 1395 1396 if (!node) { 1397 return -ENOENT; 1398 } 1399 if (!check_caller_access_to_node(fuse, hdr, node, R_OK, false)) { 1400 return -EACCES; 1401 } 1402 h = malloc(sizeof(*h)); 1403 if (!h) { 1404 return -ENOMEM; 1405 } 1406 TRACE("[%d] OPENDIR %s\n", handler->token, path); 1407 h->d = opendir(path); 1408 if (!h->d) { 1409 free(h); 1410 return -errno; 1411 } 1412 out.fh = ptr_to_id(h); 1413 out.open_flags = 0; 1414 out.padding = 0; 1415 fuse_reply(fuse, hdr->unique, &out, sizeof(out)); 1416 return NO_STATUS; 1417 } 1418 1419 static int handle_readdir(struct fuse* fuse, struct fuse_handler* handler, 1420 const struct fuse_in_header* hdr, const struct fuse_read_in* req) 1421 { 1422 char buffer[8192]; 1423 struct fuse_dirent *fde = (struct fuse_dirent*) buffer; 1424 struct dirent *de; 1425 struct dirhandle *h = id_to_ptr(req->fh); 1426 1427 TRACE("[%d] READDIR %p\n", handler->token, h); 1428 if (req->offset == 0) { 1429 /* rewinddir() might have been called above us, so rewind here too */ 1430 TRACE("[%d] calling rewinddir()\n", handler->token); 1431 rewinddir(h->d); 1432 } 1433 de = readdir(h->d); 1434 if (!de) { 1435 return 0; 1436 } 1437 fde->ino = FUSE_UNKNOWN_INO; 1438 /* increment the offset so we can detect when rewinddir() seeks back to the beginning */ 1439 fde->off = req->offset + 1; 1440 fde->type = de->d_type; 1441 fde->namelen = strlen(de->d_name); 1442 memcpy(fde->name, de->d_name, fde->namelen + 1); 1443 fuse_reply(fuse, hdr->unique, fde, 1444 FUSE_DIRENT_ALIGN(sizeof(struct fuse_dirent) + fde->namelen)); 1445 return NO_STATUS; 1446 } 1447 1448 static int handle_releasedir(struct fuse* fuse, struct fuse_handler* handler, 1449 const struct fuse_in_header* hdr, const struct fuse_release_in* req) 1450 { 1451 struct dirhandle *h = id_to_ptr(req->fh); 1452 1453 TRACE("[%d] RELEASEDIR %p\n", handler->token, h); 1454 closedir(h->d); 1455 free(h); 1456 return 0; 1457 } 1458 1459 static int handle_init(struct fuse* fuse, struct fuse_handler* handler, 1460 const struct fuse_in_header* hdr, const struct fuse_init_in* req) 1461 { 1462 struct fuse_init_out out; 1463 1464 TRACE("[%d] INIT ver=%d.%d maxread=%d flags=%x\n", 1465 handler->token, req->major, req->minor, req->max_readahead, req->flags); 1466 out.major = FUSE_KERNEL_VERSION; 1467 out.minor = FUSE_KERNEL_MINOR_VERSION; 1468 out.max_readahead = req->max_readahead; 1469 out.flags = FUSE_ATOMIC_O_TRUNC | FUSE_BIG_WRITES; 1470 out.max_background = 32; 1471 out.congestion_threshold = 32; 1472 out.max_write = MAX_WRITE; 1473 fuse_reply(fuse, hdr->unique, &out, sizeof(out)); 1474 return NO_STATUS; 1475 } 1476 1477 static int handle_fuse_request(struct fuse *fuse, struct fuse_handler* handler, 1478 const struct fuse_in_header *hdr, const void *data, size_t data_len) 1479 { 1480 switch (hdr->opcode) { 1481 case FUSE_LOOKUP: { /* bytez[] -> entry_out */ 1482 const char* name = data; 1483 return handle_lookup(fuse, handler, hdr, name); 1484 } 1485 1486 case FUSE_FORGET: { 1487 const struct fuse_forget_in *req = data; 1488 return handle_forget(fuse, handler, hdr, req); 1489 } 1490 1491 case FUSE_GETATTR: { /* getattr_in -> attr_out */ 1492 const struct fuse_getattr_in *req = data; 1493 return handle_getattr(fuse, handler, hdr, req); 1494 } 1495 1496 case FUSE_SETATTR: { /* setattr_in -> attr_out */ 1497 const struct fuse_setattr_in *req = data; 1498 return handle_setattr(fuse, handler, hdr, req); 1499 } 1500 1501 // case FUSE_READLINK: 1502 // case FUSE_SYMLINK: 1503 case FUSE_MKNOD: { /* mknod_in, bytez[] -> entry_out */ 1504 const struct fuse_mknod_in *req = data; 1505 const char *name = ((const char*) data) + sizeof(*req); 1506 return handle_mknod(fuse, handler, hdr, req, name); 1507 } 1508 1509 case FUSE_MKDIR: { /* mkdir_in, bytez[] -> entry_out */ 1510 const struct fuse_mkdir_in *req = data; 1511 const char *name = ((const char*) data) + sizeof(*req); 1512 return handle_mkdir(fuse, handler, hdr, req, name); 1513 } 1514 1515 case FUSE_UNLINK: { /* bytez[] -> */ 1516 const char* name = data; 1517 return handle_unlink(fuse, handler, hdr, name); 1518 } 1519 1520 case FUSE_RMDIR: { /* bytez[] -> */ 1521 const char* name = data; 1522 return handle_rmdir(fuse, handler, hdr, name); 1523 } 1524 1525 case FUSE_RENAME: { /* rename_in, oldname, newname -> */ 1526 const struct fuse_rename_in *req = data; 1527 const char *old_name = ((const char*) data) + sizeof(*req); 1528 const char *new_name = old_name + strlen(old_name) + 1; 1529 return handle_rename(fuse, handler, hdr, req, old_name, new_name); 1530 } 1531 1532 // case FUSE_LINK: 1533 case FUSE_OPEN: { /* open_in -> open_out */ 1534 const struct fuse_open_in *req = data; 1535 return handle_open(fuse, handler, hdr, req); 1536 } 1537 1538 case FUSE_READ: { /* read_in -> byte[] */ 1539 const struct fuse_read_in *req = data; 1540 return handle_read(fuse, handler, hdr, req); 1541 } 1542 1543 case FUSE_WRITE: { /* write_in, byte[write_in.size] -> write_out */ 1544 const struct fuse_write_in *req = data; 1545 const void* buffer = (const __u8*)data + sizeof(*req); 1546 return handle_write(fuse, handler, hdr, req, buffer); 1547 } 1548 1549 case FUSE_STATFS: { /* getattr_in -> attr_out */ 1550 return handle_statfs(fuse, handler, hdr); 1551 } 1552 1553 case FUSE_RELEASE: { /* release_in -> */ 1554 const struct fuse_release_in *req = data; 1555 return handle_release(fuse, handler, hdr, req); 1556 } 1557 1558 case FUSE_FSYNC: 1559 case FUSE_FSYNCDIR: { 1560 const struct fuse_fsync_in *req = data; 1561 return handle_fsync(fuse, handler, hdr, req); 1562 } 1563 1564 // case FUSE_SETXATTR: 1565 // case FUSE_GETXATTR: 1566 // case FUSE_LISTXATTR: 1567 // case FUSE_REMOVEXATTR: 1568 case FUSE_FLUSH: { 1569 return handle_flush(fuse, handler, hdr); 1570 } 1571 1572 case FUSE_OPENDIR: { /* open_in -> open_out */ 1573 const struct fuse_open_in *req = data; 1574 return handle_opendir(fuse, handler, hdr, req); 1575 } 1576 1577 case FUSE_READDIR: { 1578 const struct fuse_read_in *req = data; 1579 return handle_readdir(fuse, handler, hdr, req); 1580 } 1581 1582 case FUSE_RELEASEDIR: { /* release_in -> */ 1583 const struct fuse_release_in *req = data; 1584 return handle_releasedir(fuse, handler, hdr, req); 1585 } 1586 1587 case FUSE_INIT: { /* init_in -> init_out */ 1588 const struct fuse_init_in *req = data; 1589 return handle_init(fuse, handler, hdr, req); 1590 } 1591 1592 default: { 1593 TRACE("[%d] NOTIMPL op=%d uniq=%"PRIx64" nid=%"PRIx64"\n", 1594 handler->token, hdr->opcode, hdr->unique, hdr->nodeid); 1595 return -ENOSYS; 1596 } 1597 } 1598 } 1599 1600 static void handle_fuse_requests(struct fuse_handler* handler) 1601 { 1602 struct fuse* fuse = handler->fuse; 1603 for (;;) { 1604 ssize_t len = read(fuse->fd, 1605 handler->request_buffer, sizeof(handler->request_buffer)); 1606 if (len < 0) { 1607 if (errno != EINTR) { 1608 ERROR("[%d] handle_fuse_requests: errno=%d\n", handler->token, errno); 1609 } 1610 continue; 1611 } 1612 1613 if ((size_t)len < sizeof(struct fuse_in_header)) { 1614 ERROR("[%d] request too short: len=%zu\n", handler->token, (size_t)len); 1615 continue; 1616 } 1617 1618 const struct fuse_in_header *hdr = (void*)handler->request_buffer; 1619 if (hdr->len != (size_t)len) { 1620 ERROR("[%d] malformed header: len=%zu, hdr->len=%u\n", 1621 handler->token, (size_t)len, hdr->len); 1622 continue; 1623 } 1624 1625 const void *data = handler->request_buffer + sizeof(struct fuse_in_header); 1626 size_t data_len = len - sizeof(struct fuse_in_header); 1627 __u64 unique = hdr->unique; 1628 int res = handle_fuse_request(fuse, handler, hdr, data, data_len); 1629 1630 /* We do not access the request again after this point because the underlying 1631 * buffer storage may have been reused while processing the request. */ 1632 1633 if (res != NO_STATUS) { 1634 if (res) { 1635 TRACE("[%d] ERROR %d\n", handler->token, res); 1636 } 1637 fuse_status(fuse, unique, res); 1638 } 1639 } 1640 } 1641 1642 static void* start_handler(void* data) 1643 { 1644 struct fuse_handler* handler = data; 1645 handle_fuse_requests(handler); 1646 return NULL; 1647 } 1648 1649 static bool remove_str_to_int(void *key, void *value, void *context) { 1650 Hashmap* map = context; 1651 hashmapRemove(map, key); 1652 free(key); 1653 return true; 1654 } 1655 1656 static bool remove_int_to_null(void *key, void *value, void *context) { 1657 Hashmap* map = context; 1658 hashmapRemove(map, key); 1659 return true; 1660 } 1661 1662 static int read_package_list(struct fuse *fuse) { 1663 pthread_mutex_lock(&fuse->lock); 1664 1665 hashmapForEach(fuse->package_to_appid, remove_str_to_int, fuse->package_to_appid); 1666 hashmapForEach(fuse->appid_with_rw, remove_int_to_null, fuse->appid_with_rw); 1667 1668 FILE* file = fopen(kPackagesListFile, "r"); 1669 if (!file) { 1670 ERROR("failed to open package list: %s\n", strerror(errno)); 1671 pthread_mutex_unlock(&fuse->lock); 1672 return -1; 1673 } 1674 1675 char buf[512]; 1676 while (fgets(buf, sizeof(buf), file) != NULL) { 1677 char package_name[512]; 1678 int appid; 1679 char gids[512]; 1680 1681 if (sscanf(buf, "%s %d %*d %*s %*s %s", package_name, &appid, gids) == 3) { 1682 char* package_name_dup = strdup(package_name); 1683 hashmapPut(fuse->package_to_appid, package_name_dup, (void*) (uintptr_t) appid); 1684 1685 char* token = strtok(gids, ","); 1686 while (token != NULL) { 1687 if (strtoul(token, NULL, 10) == fuse->write_gid) { 1688 hashmapPut(fuse->appid_with_rw, (void*) (uintptr_t) appid, (void*) (uintptr_t) 1); 1689 break; 1690 } 1691 token = strtok(NULL, ","); 1692 } 1693 } 1694 } 1695 1696 TRACE("read_package_list: found %zu packages, %zu with write_gid\n", 1697 hashmapSize(fuse->package_to_appid), 1698 hashmapSize(fuse->appid_with_rw)); 1699 fclose(file); 1700 pthread_mutex_unlock(&fuse->lock); 1701 return 0; 1702 } 1703 1704 static void watch_package_list(struct fuse* fuse) { 1705 struct inotify_event *event; 1706 char event_buf[512]; 1707 1708 int nfd = inotify_init(); 1709 if (nfd < 0) { 1710 ERROR("inotify_init failed: %s\n", strerror(errno)); 1711 return; 1712 } 1713 1714 bool active = false; 1715 while (1) { 1716 if (!active) { 1717 int res = inotify_add_watch(nfd, kPackagesListFile, IN_DELETE_SELF); 1718 if (res == -1) { 1719 if (errno == ENOENT || errno == EACCES) { 1720 /* Framework may not have created yet, sleep and retry */ 1721 ERROR("missing packages.list; retrying\n"); 1722 sleep(3); 1723 continue; 1724 } else { 1725 ERROR("inotify_add_watch failed: %s\n", strerror(errno)); 1726 return; 1727 } 1728 } 1729 1730 /* Watch above will tell us about any future changes, so 1731 * read the current state. */ 1732 if (read_package_list(fuse) == -1) { 1733 ERROR("read_package_list failed: %s\n", strerror(errno)); 1734 return; 1735 } 1736 active = true; 1737 } 1738 1739 int event_pos = 0; 1740 int res = read(nfd, event_buf, sizeof(event_buf)); 1741 if (res < (int) sizeof(*event)) { 1742 if (errno == EINTR) 1743 continue; 1744 ERROR("failed to read inotify event: %s\n", strerror(errno)); 1745 return; 1746 } 1747 1748 while (res >= (int) sizeof(*event)) { 1749 int event_size; 1750 event = (struct inotify_event *) (event_buf + event_pos); 1751 1752 TRACE("inotify event: %08x\n", event->mask); 1753 if ((event->mask & IN_IGNORED) == IN_IGNORED) { 1754 /* Previously watched file was deleted, probably due to move 1755 * that swapped in new data; re-arm the watch and read. */ 1756 active = false; 1757 } 1758 1759 event_size = sizeof(*event) + event->len; 1760 res -= event_size; 1761 event_pos += event_size; 1762 } 1763 } 1764 } 1765 1766 static int ignite_fuse(struct fuse* fuse, int num_threads) 1767 { 1768 struct fuse_handler* handlers; 1769 int i; 1770 1771 handlers = malloc(num_threads * sizeof(struct fuse_handler)); 1772 if (!handlers) { 1773 ERROR("cannot allocate storage for threads\n"); 1774 return -ENOMEM; 1775 } 1776 1777 for (i = 0; i < num_threads; i++) { 1778 handlers[i].fuse = fuse; 1779 handlers[i].token = i; 1780 } 1781 1782 /* When deriving permissions, this thread is used to process inotify events, 1783 * otherwise it becomes one of the FUSE handlers. */ 1784 i = (fuse->derive == DERIVE_NONE) ? 1 : 0; 1785 for (; i < num_threads; i++) { 1786 pthread_t thread; 1787 int res = pthread_create(&thread, NULL, start_handler, &handlers[i]); 1788 if (res) { 1789 ERROR("failed to start thread #%d, error=%d\n", i, res); 1790 goto quit; 1791 } 1792 } 1793 1794 if (fuse->derive == DERIVE_NONE) { 1795 handle_fuse_requests(&handlers[0]); 1796 } else { 1797 watch_package_list(fuse); 1798 } 1799 1800 ERROR("terminated prematurely\n"); 1801 1802 /* don't bother killing all of the other threads or freeing anything, 1803 * should never get here anyhow */ 1804 quit: 1805 exit(1); 1806 } 1807 1808 static int usage() 1809 { 1810 ERROR("usage: sdcard [OPTIONS] <source_path> <dest_path>\n" 1811 " -u: specify UID to run as\n" 1812 " -g: specify GID to run as\n" 1813 " -w: specify GID required to write (default sdcard_rw, requires -d or -l)\n" 1814 " -t: specify number of threads to use (default %d)\n" 1815 " -d: derive file permissions based on path\n" 1816 " -l: derive file permissions based on legacy internal layout\n" 1817 " -s: split derived permissions for pics, av\n" 1818 "\n", DEFAULT_NUM_THREADS); 1819 return 1; 1820 } 1821 1822 static int run(const char* source_path, const char* dest_path, uid_t uid, 1823 gid_t gid, gid_t write_gid, int num_threads, derive_t derive, 1824 bool split_perms) { 1825 int fd; 1826 char opts[256]; 1827 int res; 1828 struct fuse fuse; 1829 1830 /* cleanup from previous instance, if necessary */ 1831 umount2(dest_path, 2); 1832 1833 fd = open("/dev/fuse", O_RDWR); 1834 if (fd < 0){ 1835 ERROR("cannot open fuse device: %s\n", strerror(errno)); 1836 return -1; 1837 } 1838 1839 snprintf(opts, sizeof(opts), 1840 "fd=%i,rootmode=40000,default_permissions,allow_other,user_id=%d,group_id=%d", 1841 fd, uid, gid); 1842 1843 res = mount("/dev/fuse", dest_path, "fuse", MS_NOSUID | MS_NODEV | MS_NOEXEC, opts); 1844 if (res < 0) { 1845 ERROR("cannot mount fuse filesystem: %s\n", strerror(errno)); 1846 goto error; 1847 } 1848 1849 res = setgroups(sizeof(kGroups) / sizeof(kGroups[0]), kGroups); 1850 if (res < 0) { 1851 ERROR("cannot setgroups: %s\n", strerror(errno)); 1852 goto error; 1853 } 1854 1855 res = setgid(gid); 1856 if (res < 0) { 1857 ERROR("cannot setgid: %s\n", strerror(errno)); 1858 goto error; 1859 } 1860 1861 res = setuid(uid); 1862 if (res < 0) { 1863 ERROR("cannot setuid: %s\n", strerror(errno)); 1864 goto error; 1865 } 1866 1867 fuse_init(&fuse, fd, source_path, write_gid, derive, split_perms); 1868 1869 umask(0); 1870 res = ignite_fuse(&fuse, num_threads); 1871 1872 /* we do not attempt to umount the file system here because we are no longer 1873 * running as the root user */ 1874 1875 error: 1876 close(fd); 1877 return res; 1878 } 1879 1880 int main(int argc, char **argv) 1881 { 1882 int res; 1883 const char *source_path = NULL; 1884 const char *dest_path = NULL; 1885 uid_t uid = 0; 1886 gid_t gid = 0; 1887 gid_t write_gid = AID_SDCARD_RW; 1888 int num_threads = DEFAULT_NUM_THREADS; 1889 derive_t derive = DERIVE_NONE; 1890 bool split_perms = false; 1891 int i; 1892 struct rlimit rlim; 1893 int fs_version; 1894 1895 int opt; 1896 while ((opt = getopt(argc, argv, "u:g:w:t:dls")) != -1) { 1897 switch (opt) { 1898 case 'u': 1899 uid = strtoul(optarg, NULL, 10); 1900 break; 1901 case 'g': 1902 gid = strtoul(optarg, NULL, 10); 1903 break; 1904 case 'w': 1905 write_gid = strtoul(optarg, NULL, 10); 1906 break; 1907 case 't': 1908 num_threads = strtoul(optarg, NULL, 10); 1909 break; 1910 case 'd': 1911 derive = DERIVE_UNIFIED; 1912 break; 1913 case 'l': 1914 derive = DERIVE_LEGACY; 1915 break; 1916 case 's': 1917 split_perms = true; 1918 break; 1919 case '?': 1920 default: 1921 return usage(); 1922 } 1923 } 1924 1925 for (i = optind; i < argc; i++) { 1926 char* arg = argv[i]; 1927 if (!source_path) { 1928 source_path = arg; 1929 } else if (!dest_path) { 1930 dest_path = arg; 1931 } else if (!uid) { 1932 uid = strtoul(arg, NULL, 10); 1933 } else if (!gid) { 1934 gid = strtoul(arg, NULL, 10); 1935 } else { 1936 ERROR("too many arguments\n"); 1937 return usage(); 1938 } 1939 } 1940 1941 if (!source_path) { 1942 ERROR("no source path specified\n"); 1943 return usage(); 1944 } 1945 if (!dest_path) { 1946 ERROR("no dest path specified\n"); 1947 return usage(); 1948 } 1949 if (!uid || !gid) { 1950 ERROR("uid and gid must be nonzero\n"); 1951 return usage(); 1952 } 1953 if (num_threads < 1) { 1954 ERROR("number of threads must be at least 1\n"); 1955 return usage(); 1956 } 1957 if (split_perms && derive == DERIVE_NONE) { 1958 ERROR("cannot split permissions without deriving\n"); 1959 return usage(); 1960 } 1961 1962 rlim.rlim_cur = 8192; 1963 rlim.rlim_max = 8192; 1964 if (setrlimit(RLIMIT_NOFILE, &rlim)) { 1965 ERROR("Error setting RLIMIT_NOFILE, errno = %d\n", errno); 1966 } 1967 1968 while ((fs_read_atomic_int("/data/.layout_version", &fs_version) == -1) || (fs_version < 3)) { 1969 ERROR("installd fs upgrade not yet complete. Waiting...\n"); 1970 sleep(1); 1971 } 1972 1973 res = run(source_path, dest_path, uid, gid, write_gid, num_threads, derive, split_perms); 1974 return res < 0 ? 1 : 0; 1975 } 1976
