Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 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 | #include <stdio.h> |
| 18 | #include <stdlib.h> |
| 19 | #include <string.h> |
| 20 | #include <unistd.h> |
| 21 | #include <errno.h> |
| 22 | #include <fcntl.h> |
| 23 | #include <sys/mount.h> |
| 24 | #include <sys/stat.h> |
Mike Lockwood | 4553b08 | 2010-08-16 14:14:44 -0400 | [diff] [blame] | 25 | #include <sys/statfs.h> |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 26 | #include <sys/uio.h> |
| 27 | #include <dirent.h> |
| 28 | |
Brian Swetland | b14a2c6 | 2010-08-12 18:21:12 -0700 | [diff] [blame] | 29 | #include <private/android_filesystem_config.h> |
| 30 | |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 31 | #include "fuse.h" |
| 32 | |
| 33 | /* README |
| 34 | * |
| 35 | * What is this? |
| 36 | * |
| 37 | * sdcard is a program that uses FUSE to emulate FAT-on-sdcard style |
| 38 | * directory permissions (all files are given fixed owner, group, and |
| 39 | * permissions at creation, owner, group, and permissions are not |
| 40 | * changeable, symlinks and hardlinks are not createable, etc. |
| 41 | * |
| 42 | * usage: sdcard <path> <uid> <gid> |
| 43 | * |
| 44 | * It must be run as root, but will change to uid/gid as soon as it |
Mike Lockwood | 4553b08 | 2010-08-16 14:14:44 -0400 | [diff] [blame] | 45 | * mounts a filesystem on /mnt/sdcard. It will refuse to run if uid or |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 46 | * gid are zero. |
| 47 | * |
| 48 | * |
| 49 | * Things I believe to be true: |
| 50 | * |
| 51 | * - ops that return a fuse_entry (LOOKUP, MKNOD, MKDIR, LINK, SYMLINK, |
| 52 | * CREAT) must bump that node's refcount |
| 53 | * - don't forget that FORGET can forget multiple references (req->nlookup) |
| 54 | * - if an op that returns a fuse_entry fails writing the reply to the |
| 55 | * kernel, you must rollback the refcount to reflect the reference the |
| 56 | * kernel did not actually acquire |
| 57 | * |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 58 | */ |
| 59 | |
| 60 | #define FUSE_TRACE 0 |
| 61 | |
| 62 | #if FUSE_TRACE |
| 63 | #define TRACE(x...) fprintf(stderr,x) |
| 64 | #else |
| 65 | #define TRACE(x...) do {} while (0) |
| 66 | #endif |
| 67 | |
| 68 | #define ERROR(x...) fprintf(stderr,x) |
| 69 | |
| 70 | #define FUSE_UNKNOWN_INO 0xffffffff |
| 71 | |
Mike Lockwood | 4553b08 | 2010-08-16 14:14:44 -0400 | [diff] [blame] | 72 | #define MOUNT_POINT "/mnt/sdcard" |
| 73 | |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 74 | struct handle { |
| 75 | struct node *node; |
| 76 | int fd; |
| 77 | }; |
| 78 | |
| 79 | struct dirhandle { |
| 80 | struct node *node; |
| 81 | DIR *d; |
| 82 | }; |
| 83 | |
| 84 | struct node { |
| 85 | __u64 nid; |
| 86 | __u64 gen; |
| 87 | |
Paul Eastham | 11ccdb3 | 2010-10-14 11:04:26 -0700 | [diff] [blame] | 88 | struct node *next; /* per-dir sibling list */ |
| 89 | struct node *child; /* first contained file by this dir */ |
| 90 | struct node *all; /* global node list */ |
| 91 | struct node *parent; /* containing directory */ |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 92 | |
| 93 | __u32 refcount; |
| 94 | __u32 namelen; |
| 95 | |
Paul Eastham | 11ccdb3 | 2010-10-14 11:04:26 -0700 | [diff] [blame] | 96 | char *name; |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 97 | }; |
| 98 | |
| 99 | struct fuse { |
| 100 | __u64 next_generation; |
| 101 | __u64 next_node_id; |
| 102 | |
| 103 | int fd; |
| 104 | |
| 105 | struct node *all; |
| 106 | |
| 107 | struct node root; |
| 108 | char rootpath[1024]; |
| 109 | }; |
| 110 | |
| 111 | #define PATH_BUFFER_SIZE 1024 |
| 112 | |
Paul Eastham | f43219e | 2010-09-21 17:14:31 -0700 | [diff] [blame] | 113 | /* |
| 114 | * Get the real-life absolute path to a node. |
| 115 | * node: start at this node |
| 116 | * buf: storage for returned string |
| 117 | * name: append this string to path if set |
| 118 | */ |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 119 | char *node_get_path(struct node *node, char *buf, const char *name) |
| 120 | { |
| 121 | char *out = buf + PATH_BUFFER_SIZE - 1; |
| 122 | int len; |
| 123 | out[0] = 0; |
| 124 | |
| 125 | if (name) { |
| 126 | len = strlen(name); |
| 127 | goto start; |
| 128 | } |
| 129 | |
| 130 | while (node) { |
| 131 | name = node->name; |
| 132 | len = node->namelen; |
| 133 | node = node->parent; |
| 134 | start: |
| 135 | if ((len + 1) > (out - buf)) |
| 136 | return 0; |
| 137 | out -= len; |
| 138 | memcpy(out, name, len); |
| 139 | out --; |
| 140 | out[0] = '/'; |
| 141 | } |
| 142 | |
| 143 | return out; |
| 144 | } |
| 145 | |
| 146 | void attr_from_stat(struct fuse_attr *attr, struct stat *s) |
| 147 | { |
| 148 | attr->ino = s->st_ino; |
| 149 | attr->size = s->st_size; |
| 150 | attr->blocks = s->st_blocks; |
Mike Lockwood | 4553b08 | 2010-08-16 14:14:44 -0400 | [diff] [blame] | 151 | attr->atime = s->st_atime; |
| 152 | attr->mtime = s->st_mtime; |
| 153 | attr->ctime = s->st_ctime; |
| 154 | attr->atimensec = s->st_atime_nsec; |
| 155 | attr->mtimensec = s->st_mtime_nsec; |
| 156 | attr->ctimensec = s->st_ctime_nsec; |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 157 | attr->mode = s->st_mode; |
| 158 | attr->nlink = s->st_nlink; |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 159 | |
Brian Swetland | b14a2c6 | 2010-08-12 18:21:12 -0700 | [diff] [blame] | 160 | /* force permissions to something reasonable: |
| 161 | * world readable |
| 162 | * writable by the sdcard group |
| 163 | */ |
| 164 | if (attr->mode & 0100) { |
| 165 | attr->mode = (attr->mode & (~0777)) | 0775; |
| 166 | } else { |
| 167 | attr->mode = (attr->mode & (~0777)) | 0664; |
| 168 | } |
| 169 | |
| 170 | /* all files owned by root.sdcard */ |
| 171 | attr->uid = 0; |
| 172 | attr->gid = AID_SDCARD_RW; |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 173 | } |
| 174 | |
| 175 | int node_get_attr(struct node *node, struct fuse_attr *attr) |
| 176 | { |
| 177 | int res; |
| 178 | struct stat s; |
| 179 | char *path, buffer[PATH_BUFFER_SIZE]; |
| 180 | |
| 181 | path = node_get_path(node, buffer, 0); |
| 182 | res = lstat(path, &s); |
| 183 | if (res < 0) { |
| 184 | ERROR("lstat('%s') errno %d\n", path, errno); |
| 185 | return -1; |
| 186 | } |
| 187 | |
| 188 | attr_from_stat(attr, &s); |
| 189 | attr->ino = node->nid; |
| 190 | |
| 191 | return 0; |
| 192 | } |
| 193 | |
Paul Eastham | 11ccdb3 | 2010-10-14 11:04:26 -0700 | [diff] [blame] | 194 | static void add_node_to_parent(struct node *node, struct node *parent) { |
| 195 | node->parent = parent; |
| 196 | node->next = parent->child; |
| 197 | parent->child = node; |
Paul Eastham | 77085c5 | 2011-01-04 21:06:03 -0800 | [diff] [blame^] | 198 | parent->refcount++; |
Paul Eastham | 11ccdb3 | 2010-10-14 11:04:26 -0700 | [diff] [blame] | 199 | } |
| 200 | |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 201 | struct node *node_create(struct node *parent, const char *name, __u64 nid, __u64 gen) |
| 202 | { |
| 203 | struct node *node; |
| 204 | int namelen = strlen(name); |
| 205 | |
Paul Eastham | 11ccdb3 | 2010-10-14 11:04:26 -0700 | [diff] [blame] | 206 | node = calloc(1, sizeof(struct node)); |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 207 | if (node == 0) { |
| 208 | return 0; |
| 209 | } |
Paul Eastham | 11ccdb3 | 2010-10-14 11:04:26 -0700 | [diff] [blame] | 210 | node->name = malloc(namelen + 1); |
| 211 | if (node->name == 0) { |
| 212 | free(node); |
| 213 | return 0; |
| 214 | } |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 215 | |
| 216 | node->nid = nid; |
| 217 | node->gen = gen; |
Paul Eastham | 11ccdb3 | 2010-10-14 11:04:26 -0700 | [diff] [blame] | 218 | add_node_to_parent(node, parent); |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 219 | memcpy(node->name, name, namelen + 1); |
| 220 | node->namelen = namelen; |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 221 | |
| 222 | return node; |
| 223 | } |
| 224 | |
Paul Eastham | 11ccdb3 | 2010-10-14 11:04:26 -0700 | [diff] [blame] | 225 | static char *rename_node(struct node *node, const char *name) |
| 226 | { |
| 227 | node->namelen = strlen(name); |
| 228 | char *newname = realloc(node->name, node->namelen + 1); |
| 229 | if (newname == 0) |
| 230 | return 0; |
| 231 | node->name = newname; |
| 232 | memcpy(node->name, name, node->namelen + 1); |
| 233 | return node->name; |
| 234 | } |
| 235 | |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 236 | void fuse_init(struct fuse *fuse, int fd, const char *path) |
| 237 | { |
| 238 | fuse->fd = fd; |
| 239 | fuse->next_node_id = 2; |
| 240 | fuse->next_generation = 0; |
| 241 | |
| 242 | fuse->all = &fuse->root; |
| 243 | |
| 244 | fuse->root.nid = FUSE_ROOT_ID; /* 1 */ |
| 245 | fuse->root.next = 0; |
| 246 | fuse->root.child = 0; |
| 247 | fuse->root.parent = 0; |
| 248 | |
| 249 | fuse->root.all = 0; |
| 250 | fuse->root.refcount = 2; |
| 251 | |
Paul Eastham | 11ccdb3 | 2010-10-14 11:04:26 -0700 | [diff] [blame] | 252 | fuse->root.name = 0; |
| 253 | rename_node(&fuse->root, path); |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 254 | } |
| 255 | |
| 256 | static inline void *id_to_ptr(__u64 nid) |
| 257 | { |
| 258 | return (void *) nid; |
| 259 | } |
| 260 | |
| 261 | static inline __u64 ptr_to_id(void *ptr) |
| 262 | { |
| 263 | return (__u64) ptr; |
| 264 | } |
| 265 | |
| 266 | |
| 267 | struct node *lookup_by_inode(struct fuse *fuse, __u64 nid) |
| 268 | { |
| 269 | if (nid == FUSE_ROOT_ID) { |
| 270 | return &fuse->root; |
| 271 | } else { |
| 272 | return id_to_ptr(nid); |
| 273 | } |
| 274 | } |
| 275 | |
| 276 | struct node *lookup_child_by_name(struct node *node, const char *name) |
| 277 | { |
| 278 | for (node = node->child; node; node = node->next) { |
| 279 | if (!strcmp(name, node->name)) { |
| 280 | return node; |
| 281 | } |
| 282 | } |
| 283 | return 0; |
| 284 | } |
| 285 | |
| 286 | struct node *lookup_child_by_inode(struct node *node, __u64 nid) |
| 287 | { |
| 288 | for (node = node->child; node; node = node->next) { |
| 289 | if (node->nid == nid) { |
| 290 | return node; |
| 291 | } |
| 292 | } |
| 293 | return 0; |
| 294 | } |
| 295 | |
Paul Eastham | 77085c5 | 2011-01-04 21:06:03 -0800 | [diff] [blame^] | 296 | static void dec_refcount(struct node *node) { |
| 297 | if (node->refcount > 0) { |
| 298 | node->refcount--; |
| 299 | TRACE("dec_refcount %p(%s) -> %d\n", node, node->name, node->refcount); |
| 300 | } else { |
| 301 | ERROR("Zero refcnt %p\n", node); |
| 302 | } |
| 303 | } |
| 304 | |
Paul Eastham | 11ccdb3 | 2010-10-14 11:04:26 -0700 | [diff] [blame] | 305 | static struct node *remove_child(struct node *parent, __u64 nid) |
| 306 | { |
| 307 | struct node *prev = 0; |
| 308 | struct node *node; |
| 309 | |
| 310 | for (node = parent->child; node; node = node->next) { |
| 311 | if (node->nid == nid) { |
| 312 | if (prev) { |
| 313 | prev->next = node->next; |
| 314 | } else { |
| 315 | parent->child = node->next; |
| 316 | } |
| 317 | node->next = 0; |
| 318 | node->parent = 0; |
Paul Eastham | 77085c5 | 2011-01-04 21:06:03 -0800 | [diff] [blame^] | 319 | dec_refcount(parent); |
Paul Eastham | 11ccdb3 | 2010-10-14 11:04:26 -0700 | [diff] [blame] | 320 | return node; |
| 321 | } |
| 322 | prev = node; |
| 323 | } |
| 324 | return 0; |
| 325 | } |
| 326 | |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 327 | struct node *node_lookup(struct fuse *fuse, struct node *parent, const char *name, |
| 328 | struct fuse_attr *attr) |
| 329 | { |
| 330 | int res; |
| 331 | struct stat s; |
| 332 | char *path, buffer[PATH_BUFFER_SIZE]; |
| 333 | struct node *node; |
| 334 | |
| 335 | path = node_get_path(parent, buffer, name); |
| 336 | /* XXX error? */ |
| 337 | |
| 338 | res = lstat(path, &s); |
| 339 | if (res < 0) |
| 340 | return 0; |
| 341 | |
| 342 | node = lookup_child_by_name(parent, name); |
| 343 | if (!node) { |
| 344 | node = node_create(parent, name, fuse->next_node_id++, fuse->next_generation++); |
| 345 | if (!node) |
| 346 | return 0; |
| 347 | node->nid = ptr_to_id(node); |
| 348 | node->all = fuse->all; |
| 349 | fuse->all = node; |
| 350 | } |
| 351 | |
| 352 | attr_from_stat(attr, &s); |
| 353 | attr->ino = node->nid; |
| 354 | |
| 355 | return node; |
| 356 | } |
| 357 | |
| 358 | void node_release(struct node *node) |
| 359 | { |
| 360 | TRACE("RELEASE %p (%s) rc=%d\n", node, node->name, node->refcount); |
Paul Eastham | 77085c5 | 2011-01-04 21:06:03 -0800 | [diff] [blame^] | 361 | dec_refcount(node); |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 362 | if (node->refcount == 0) { |
| 363 | if (node->parent->child == node) { |
| 364 | node->parent->child = node->parent->child->next; |
| 365 | } else { |
| 366 | struct node *node2; |
| 367 | |
| 368 | node2 = node->parent->child; |
| 369 | while (node2->next != node) |
| 370 | node2 = node2->next; |
| 371 | node2->next = node->next; |
| 372 | } |
| 373 | |
| 374 | TRACE("DESTROY %p (%s)\n", node, node->name); |
| 375 | |
| 376 | node_release(node->parent); |
| 377 | |
| 378 | node->parent = 0; |
| 379 | node->next = 0; |
| 380 | |
| 381 | /* TODO: remove debugging - poison memory */ |
Paul Eastham | 11ccdb3 | 2010-10-14 11:04:26 -0700 | [diff] [blame] | 382 | memset(node->name, 0xef, node->namelen); |
| 383 | free(node->name); |
Paul Eastham | 77085c5 | 2011-01-04 21:06:03 -0800 | [diff] [blame^] | 384 | memset(node, 0xfc, sizeof(*node)); |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 385 | free(node); |
| 386 | } |
| 387 | } |
| 388 | |
| 389 | void fuse_status(struct fuse *fuse, __u64 unique, int err) |
| 390 | { |
| 391 | struct fuse_out_header hdr; |
| 392 | hdr.len = sizeof(hdr); |
| 393 | hdr.error = err; |
| 394 | hdr.unique = unique; |
| 395 | if (err) { |
| 396 | // ERROR("*** %d ***\n", err); |
| 397 | } |
| 398 | write(fuse->fd, &hdr, sizeof(hdr)); |
| 399 | } |
| 400 | |
| 401 | void fuse_reply(struct fuse *fuse, __u64 unique, void *data, int len) |
| 402 | { |
| 403 | struct fuse_out_header hdr; |
| 404 | struct iovec vec[2]; |
| 405 | int res; |
| 406 | |
| 407 | hdr.len = len + sizeof(hdr); |
| 408 | hdr.error = 0; |
| 409 | hdr.unique = unique; |
| 410 | |
| 411 | vec[0].iov_base = &hdr; |
| 412 | vec[0].iov_len = sizeof(hdr); |
| 413 | vec[1].iov_base = data; |
| 414 | vec[1].iov_len = len; |
| 415 | |
| 416 | res = writev(fuse->fd, vec, 2); |
| 417 | if (res < 0) { |
| 418 | ERROR("*** REPLY FAILED *** %d\n", errno); |
| 419 | } |
| 420 | } |
| 421 | |
| 422 | void lookup_entry(struct fuse *fuse, struct node *node, |
| 423 | const char *name, __u64 unique) |
| 424 | { |
| 425 | struct fuse_entry_out out; |
| 426 | |
| 427 | memset(&out, 0, sizeof(out)); |
| 428 | |
| 429 | node = node_lookup(fuse, node, name, &out.attr); |
| 430 | if (!node) { |
| 431 | fuse_status(fuse, unique, -ENOENT); |
| 432 | return; |
| 433 | } |
| 434 | |
| 435 | node->refcount++; |
| 436 | // fprintf(stderr,"ACQUIRE %p (%s) rc=%d\n", node, node->name, node->refcount); |
| 437 | out.nodeid = node->nid; |
| 438 | out.generation = node->gen; |
| 439 | out.entry_valid = 10; |
| 440 | out.attr_valid = 10; |
| 441 | |
| 442 | fuse_reply(fuse, unique, &out, sizeof(out)); |
| 443 | } |
| 444 | |
| 445 | void handle_fuse_request(struct fuse *fuse, struct fuse_in_header *hdr, void *data, unsigned len) |
| 446 | { |
| 447 | struct node *node; |
| 448 | |
| 449 | if ((len < sizeof(*hdr)) || (hdr->len != len)) { |
| 450 | ERROR("malformed header\n"); |
| 451 | return; |
| 452 | } |
| 453 | |
| 454 | len -= hdr->len; |
| 455 | |
| 456 | if (hdr->nodeid) { |
| 457 | node = lookup_by_inode(fuse, hdr->nodeid); |
| 458 | if (!node) { |
| 459 | fuse_status(fuse, hdr->unique, -ENOENT); |
| 460 | return; |
| 461 | } |
| 462 | } else { |
| 463 | node = 0; |
| 464 | } |
| 465 | |
| 466 | switch (hdr->opcode) { |
| 467 | case FUSE_LOOKUP: { /* bytez[] -> entry_out */ |
| 468 | TRACE("LOOKUP %llx %s\n", hdr->nodeid, (char*) data); |
| 469 | lookup_entry(fuse, node, (char*) data, hdr->unique); |
| 470 | return; |
| 471 | } |
| 472 | case FUSE_FORGET: { |
| 473 | struct fuse_forget_in *req = data; |
| 474 | TRACE("FORGET %llx (%s) #%lld\n", hdr->nodeid, node->name, req->nlookup); |
| 475 | /* no reply */ |
| 476 | while (req->nlookup--) |
| 477 | node_release(node); |
| 478 | return; |
| 479 | } |
| 480 | case FUSE_GETATTR: { /* getattr_in -> attr_out */ |
| 481 | struct fuse_getattr_in *req = data; |
| 482 | struct fuse_attr_out out; |
| 483 | |
Paul Eastham | 11ccdb3 | 2010-10-14 11:04:26 -0700 | [diff] [blame] | 484 | TRACE("GETATTR flags=%x fh=%llx\n", req->getattr_flags, req->fh); |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 485 | |
| 486 | memset(&out, 0, sizeof(out)); |
| 487 | node_get_attr(node, &out.attr); |
| 488 | out.attr_valid = 10; |
| 489 | |
| 490 | fuse_reply(fuse, hdr->unique, &out, sizeof(out)); |
| 491 | return; |
| 492 | } |
| 493 | case FUSE_SETATTR: { /* setattr_in -> attr_out */ |
| 494 | struct fuse_setattr_in *req = data; |
| 495 | struct fuse_attr_out out; |
Paul Eastham | f43219e | 2010-09-21 17:14:31 -0700 | [diff] [blame] | 496 | char *path, buffer[PATH_BUFFER_SIZE]; |
| 497 | int res = 0; |
| 498 | |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 499 | TRACE("SETATTR fh=%llx id=%llx valid=%x\n", |
| 500 | req->fh, hdr->nodeid, req->valid); |
| 501 | |
Paul Eastham | f43219e | 2010-09-21 17:14:31 -0700 | [diff] [blame] | 502 | /* XXX: incomplete implementation -- truncate only. chmod/chown |
| 503 | * should NEVER be implemented. */ |
| 504 | |
| 505 | path = node_get_path(node, buffer, 0); |
| 506 | if (req->valid & FATTR_SIZE) |
| 507 | res = truncate(path, req->size); |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 508 | |
| 509 | memset(&out, 0, sizeof(out)); |
| 510 | node_get_attr(node, &out.attr); |
| 511 | out.attr_valid = 10; |
Paul Eastham | f43219e | 2010-09-21 17:14:31 -0700 | [diff] [blame] | 512 | |
| 513 | if (res) |
| 514 | fuse_status(fuse, hdr->unique, -errno); |
| 515 | else |
| 516 | fuse_reply(fuse, hdr->unique, &out, sizeof(out)); |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 517 | return; |
| 518 | } |
| 519 | // case FUSE_READLINK: |
| 520 | // case FUSE_SYMLINK: |
| 521 | case FUSE_MKNOD: { /* mknod_in, bytez[] -> entry_out */ |
| 522 | struct fuse_mknod_in *req = data; |
| 523 | char *path, buffer[PATH_BUFFER_SIZE]; |
| 524 | char *name = ((char*) data) + sizeof(*req); |
| 525 | int res; |
| 526 | TRACE("MKNOD %s @ %llx\n", name, hdr->nodeid); |
| 527 | path = node_get_path(node, buffer, name); |
| 528 | |
| 529 | req->mode = (req->mode & (~0777)) | 0664; |
| 530 | res = mknod(path, req->mode, req->rdev); /* XXX perm?*/ |
| 531 | if (res < 0) { |
| 532 | fuse_status(fuse, hdr->unique, -errno); |
| 533 | } else { |
| 534 | lookup_entry(fuse, node, name, hdr->unique); |
| 535 | } |
| 536 | return; |
| 537 | } |
| 538 | case FUSE_MKDIR: { /* mkdir_in, bytez[] -> entry_out */ |
| 539 | struct fuse_mkdir_in *req = data; |
| 540 | struct fuse_entry_out out; |
| 541 | char *path, buffer[PATH_BUFFER_SIZE]; |
| 542 | char *name = ((char*) data) + sizeof(*req); |
| 543 | int res; |
| 544 | TRACE("MKDIR %s @ %llx 0%o\n", name, hdr->nodeid, req->mode); |
| 545 | path = node_get_path(node, buffer, name); |
| 546 | |
| 547 | req->mode = (req->mode & (~0777)) | 0775; |
| 548 | res = mkdir(path, req->mode); |
| 549 | if (res < 0) { |
| 550 | fuse_status(fuse, hdr->unique, -errno); |
| 551 | } else { |
| 552 | lookup_entry(fuse, node, name, hdr->unique); |
| 553 | } |
| 554 | return; |
| 555 | } |
| 556 | case FUSE_UNLINK: { /* bytez[] -> */ |
| 557 | char *path, buffer[PATH_BUFFER_SIZE]; |
| 558 | int res; |
| 559 | TRACE("UNLINK %s @ %llx\n", (char*) data, hdr->nodeid); |
| 560 | path = node_get_path(node, buffer, (char*) data); |
| 561 | res = unlink(path); |
| 562 | fuse_status(fuse, hdr->unique, res ? -errno : 0); |
| 563 | return; |
| 564 | } |
| 565 | case FUSE_RMDIR: { /* bytez[] -> */ |
| 566 | char *path, buffer[PATH_BUFFER_SIZE]; |
| 567 | int res; |
| 568 | TRACE("RMDIR %s @ %llx\n", (char*) data, hdr->nodeid); |
| 569 | path = node_get_path(node, buffer, (char*) data); |
| 570 | res = rmdir(path); |
| 571 | fuse_status(fuse, hdr->unique, res ? -errno : 0); |
| 572 | return; |
| 573 | } |
| 574 | case FUSE_RENAME: { /* rename_in, oldname, newname -> */ |
| 575 | struct fuse_rename_in *req = data; |
| 576 | char *oldname = ((char*) data) + sizeof(*req); |
| 577 | char *newname = oldname + strlen(oldname) + 1; |
| 578 | char *oldpath, oldbuffer[PATH_BUFFER_SIZE]; |
| 579 | char *newpath, newbuffer[PATH_BUFFER_SIZE]; |
Paul Eastham | 11ccdb3 | 2010-10-14 11:04:26 -0700 | [diff] [blame] | 580 | struct node *target; |
| 581 | struct node *newparent; |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 582 | int res; |
| 583 | |
Paul Eastham | 11ccdb3 | 2010-10-14 11:04:26 -0700 | [diff] [blame] | 584 | TRACE("RENAME %s->%s @ %llx\n", oldname, newname, hdr->nodeid); |
| 585 | |
| 586 | target = lookup_child_by_name(node, oldname); |
| 587 | if (!target) { |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 588 | fuse_status(fuse, hdr->unique, -ENOENT); |
| 589 | return; |
| 590 | } |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 591 | oldpath = node_get_path(node, oldbuffer, oldname); |
Paul Eastham | 11ccdb3 | 2010-10-14 11:04:26 -0700 | [diff] [blame] | 592 | |
| 593 | newparent = lookup_by_inode(fuse, req->newdir); |
| 594 | if (!newparent) { |
| 595 | fuse_status(fuse, hdr->unique, -ENOENT); |
| 596 | return; |
| 597 | } |
| 598 | newpath = node_get_path(newparent, newbuffer, newname); |
| 599 | |
| 600 | if (!remove_child(node, target->nid)) { |
| 601 | ERROR("RENAME remove_child not found"); |
| 602 | fuse_status(fuse, hdr->unique, -ENOENT); |
| 603 | return; |
| 604 | } |
| 605 | if (!rename_node(target, newname)) { |
| 606 | fuse_status(fuse, hdr->unique, -ENOMEM); |
| 607 | return; |
| 608 | } |
| 609 | add_node_to_parent(target, newparent); |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 610 | |
| 611 | res = rename(oldpath, newpath); |
Paul Eastham | 11ccdb3 | 2010-10-14 11:04:26 -0700 | [diff] [blame] | 612 | TRACE("RENAME result %d\n", res); |
| 613 | |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 614 | fuse_status(fuse, hdr->unique, res ? -errno : 0); |
| 615 | return; |
| 616 | } |
| 617 | // case FUSE_LINK: |
| 618 | case FUSE_OPEN: { /* open_in -> open_out */ |
| 619 | struct fuse_open_in *req = data; |
| 620 | struct fuse_open_out out; |
| 621 | char *path, buffer[PATH_BUFFER_SIZE]; |
| 622 | struct handle *h; |
| 623 | |
| 624 | h = malloc(sizeof(*h)); |
| 625 | if (!h) { |
| 626 | fuse_status(fuse, hdr->unique, -ENOMEM); |
| 627 | return; |
| 628 | } |
| 629 | |
| 630 | path = node_get_path(node, buffer, 0); |
| 631 | TRACE("OPEN %llx '%s' 0%o fh=%p\n", hdr->nodeid, path, req->flags, h); |
| 632 | h->fd = open(path, req->flags); |
| 633 | if (h->fd < 0) { |
| 634 | ERROR("ERROR\n"); |
| 635 | fuse_status(fuse, hdr->unique, errno); |
| 636 | free(h); |
| 637 | return; |
| 638 | } |
| 639 | out.fh = ptr_to_id(h); |
| 640 | out.open_flags = 0; |
| 641 | out.padding = 0; |
| 642 | fuse_reply(fuse, hdr->unique, &out, sizeof(out)); |
| 643 | return; |
| 644 | } |
| 645 | case FUSE_READ: { /* read_in -> byte[] */ |
| 646 | char buffer[128 * 1024]; |
| 647 | struct fuse_read_in *req = data; |
| 648 | struct handle *h = id_to_ptr(req->fh); |
| 649 | int res; |
| 650 | TRACE("READ %p(%d) %u@%llu\n", h, h->fd, req->size, req->offset); |
| 651 | if (req->size > sizeof(buffer)) { |
| 652 | fuse_status(fuse, hdr->unique, -EINVAL); |
| 653 | return; |
| 654 | } |
| 655 | res = pread(h->fd, buffer, req->size, req->offset); |
| 656 | if (res < 0) { |
| 657 | fuse_status(fuse, hdr->unique, errno); |
| 658 | return; |
| 659 | } |
| 660 | fuse_reply(fuse, hdr->unique, buffer, res); |
| 661 | return; |
| 662 | } |
| 663 | case FUSE_WRITE: { /* write_in, byte[write_in.size] -> write_out */ |
| 664 | struct fuse_write_in *req = data; |
| 665 | struct fuse_write_out out; |
| 666 | struct handle *h = id_to_ptr(req->fh); |
| 667 | int res; |
| 668 | TRACE("WRITE %p(%d) %u@%llu\n", h, h->fd, req->size, req->offset); |
| 669 | res = pwrite(h->fd, ((char*) data) + sizeof(*req), req->size, req->offset); |
| 670 | if (res < 0) { |
| 671 | fuse_status(fuse, hdr->unique, errno); |
| 672 | return; |
| 673 | } |
| 674 | out.size = res; |
| 675 | fuse_reply(fuse, hdr->unique, &out, sizeof(out)); |
| 676 | goto oops; |
| 677 | } |
Mike Lockwood | 4553b08 | 2010-08-16 14:14:44 -0400 | [diff] [blame] | 678 | case FUSE_STATFS: { /* getattr_in -> attr_out */ |
| 679 | struct statfs stat; |
| 680 | struct fuse_statfs_out out; |
| 681 | int res; |
| 682 | |
| 683 | TRACE("STATFS\n"); |
| 684 | |
| 685 | if (statfs(fuse->root.name, &stat)) { |
| 686 | fuse_status(fuse, hdr->unique, -errno); |
| 687 | return; |
| 688 | } |
| 689 | |
| 690 | memset(&out, 0, sizeof(out)); |
| 691 | out.st.blocks = stat.f_blocks; |
| 692 | out.st.bfree = stat.f_bfree; |
| 693 | out.st.bavail = stat.f_bavail; |
| 694 | out.st.files = stat.f_files; |
| 695 | out.st.ffree = stat.f_ffree; |
| 696 | out.st.bsize = stat.f_bsize; |
| 697 | out.st.namelen = stat.f_namelen; |
| 698 | out.st.frsize = stat.f_frsize; |
| 699 | fuse_reply(fuse, hdr->unique, &out, sizeof(out)); |
| 700 | return; |
| 701 | } |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 702 | case FUSE_RELEASE: { /* release_in -> */ |
| 703 | struct fuse_release_in *req = data; |
| 704 | struct handle *h = id_to_ptr(req->fh); |
| 705 | TRACE("RELEASE %p(%d)\n", h, h->fd); |
| 706 | close(h->fd); |
| 707 | free(h); |
| 708 | fuse_status(fuse, hdr->unique, 0); |
| 709 | return; |
| 710 | } |
| 711 | // case FUSE_FSYNC: |
| 712 | // case FUSE_SETXATTR: |
| 713 | // case FUSE_GETXATTR: |
| 714 | // case FUSE_LISTXATTR: |
| 715 | // case FUSE_REMOVEXATTR: |
| 716 | case FUSE_FLUSH: |
| 717 | fuse_status(fuse, hdr->unique, 0); |
| 718 | return; |
| 719 | case FUSE_OPENDIR: { /* open_in -> open_out */ |
| 720 | struct fuse_open_in *req = data; |
| 721 | struct fuse_open_out out; |
| 722 | char *path, buffer[PATH_BUFFER_SIZE]; |
| 723 | struct dirhandle *h; |
| 724 | |
| 725 | h = malloc(sizeof(*h)); |
| 726 | if (!h) { |
| 727 | fuse_status(fuse, hdr->unique, -ENOMEM); |
| 728 | return; |
| 729 | } |
| 730 | |
| 731 | path = node_get_path(node, buffer, 0); |
| 732 | TRACE("OPENDIR %llx '%s'\n", hdr->nodeid, path); |
| 733 | h->d = opendir(path); |
| 734 | if (h->d == 0) { |
| 735 | ERROR("ERROR\n"); |
| 736 | fuse_status(fuse, hdr->unique, -errno); |
| 737 | free(h); |
| 738 | return; |
| 739 | } |
| 740 | out.fh = ptr_to_id(h); |
| 741 | fuse_reply(fuse, hdr->unique, &out, sizeof(out)); |
| 742 | return; |
| 743 | } |
| 744 | case FUSE_READDIR: { |
| 745 | struct fuse_read_in *req = data; |
| 746 | char buffer[8192]; |
| 747 | struct fuse_dirent *fde = (struct fuse_dirent*) buffer; |
| 748 | struct dirent *de; |
| 749 | struct dirhandle *h = id_to_ptr(req->fh); |
| 750 | TRACE("READDIR %p\n", h); |
| 751 | de = readdir(h->d); |
| 752 | if (!de) { |
| 753 | fuse_status(fuse, hdr->unique, 0); |
| 754 | return; |
| 755 | } |
| 756 | fde->ino = FUSE_UNKNOWN_INO; |
| 757 | fde->off = 0; |
| 758 | fde->type = de->d_type; |
| 759 | fde->namelen = strlen(de->d_name); |
| 760 | memcpy(fde->name, de->d_name, fde->namelen + 1); |
| 761 | fuse_reply(fuse, hdr->unique, fde, |
| 762 | FUSE_DIRENT_ALIGN(sizeof(struct fuse_dirent) + fde->namelen)); |
| 763 | return; |
| 764 | } |
| 765 | case FUSE_RELEASEDIR: { /* release_in -> */ |
| 766 | struct fuse_release_in *req = data; |
| 767 | struct dirhandle *h = id_to_ptr(req->fh); |
| 768 | TRACE("RELEASEDIR %p\n",h); |
| 769 | closedir(h->d); |
| 770 | free(h); |
| 771 | fuse_status(fuse, hdr->unique, 0); |
| 772 | return; |
| 773 | } |
| 774 | // case FUSE_FSYNCDIR: |
| 775 | case FUSE_INIT: { /* init_in -> init_out */ |
| 776 | struct fuse_init_in *req = data; |
| 777 | struct fuse_init_out out; |
| 778 | |
| 779 | TRACE("INIT ver=%d.%d maxread=%d flags=%x\n", |
| 780 | req->major, req->minor, req->max_readahead, req->flags); |
| 781 | |
| 782 | out.major = FUSE_KERNEL_VERSION; |
| 783 | out.minor = FUSE_KERNEL_MINOR_VERSION; |
| 784 | out.max_readahead = req->max_readahead; |
Mike Lockwood | fc1a13b | 2010-08-20 10:29:29 -0400 | [diff] [blame] | 785 | out.flags = FUSE_ATOMIC_O_TRUNC; |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 786 | out.max_background = 32; |
| 787 | out.congestion_threshold = 32; |
| 788 | out.max_write = 256 * 1024; |
| 789 | |
| 790 | fuse_reply(fuse, hdr->unique, &out, sizeof(out)); |
| 791 | return; |
| 792 | } |
| 793 | default: { |
| 794 | struct fuse_out_header h; |
| 795 | ERROR("NOTIMPL op=%d uniq=%llx nid=%llx\n", |
| 796 | hdr->opcode, hdr->unique, hdr->nodeid); |
| 797 | |
| 798 | oops: |
| 799 | h.len = sizeof(h); |
| 800 | h.error = -ENOSYS; |
| 801 | h.unique = hdr->unique; |
| 802 | write(fuse->fd, &h, sizeof(h)); |
| 803 | break; |
| 804 | } |
| 805 | } |
| 806 | } |
| 807 | |
| 808 | void handle_fuse_requests(struct fuse *fuse) |
| 809 | { |
| 810 | unsigned char req[256 * 1024 + 128]; |
| 811 | int len; |
| 812 | |
| 813 | for (;;) { |
| 814 | len = read(fuse->fd, req, 8192); |
| 815 | if (len < 0) { |
| 816 | if (errno == EINTR) |
| 817 | continue; |
| 818 | ERROR("handle_fuse_requests: errno=%d\n", errno); |
| 819 | return; |
| 820 | } |
| 821 | handle_fuse_request(fuse, (void*) req, (void*) (req + sizeof(struct fuse_in_header)), len); |
| 822 | } |
| 823 | } |
| 824 | |
| 825 | int main(int argc, char **argv) |
| 826 | { |
| 827 | struct fuse fuse; |
| 828 | char opts[256]; |
| 829 | int fd; |
| 830 | int res; |
| 831 | unsigned uid; |
| 832 | unsigned gid; |
| 833 | const char *path; |
| 834 | |
| 835 | if (argc != 4) { |
| 836 | ERROR("usage: sdcard <path> <uid> <gid>\n"); |
| 837 | return -1; |
| 838 | } |
| 839 | |
| 840 | uid = strtoul(argv[2], 0, 10); |
| 841 | gid = strtoul(argv[3], 0, 10); |
| 842 | if (!uid || !gid) { |
| 843 | ERROR("uid and gid must be nonzero\n"); |
| 844 | return -1; |
| 845 | } |
| 846 | |
| 847 | path = argv[1]; |
| 848 | |
| 849 | /* cleanup from previous instance, if necessary */ |
Mike Lockwood | 4553b08 | 2010-08-16 14:14:44 -0400 | [diff] [blame] | 850 | umount2(MOUNT_POINT, 2); |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 851 | |
| 852 | fd = open("/dev/fuse", O_RDWR); |
| 853 | if (fd < 0){ |
| 854 | ERROR("cannot open fuse device (%d)\n", errno); |
| 855 | return -1; |
| 856 | } |
| 857 | |
| 858 | sprintf(opts, "fd=%i,rootmode=40000,default_permissions,allow_other," |
| 859 | "user_id=%d,group_id=%d", fd, uid, gid); |
| 860 | |
Mike Lockwood | 4553b08 | 2010-08-16 14:14:44 -0400 | [diff] [blame] | 861 | res = mount("/dev/fuse", MOUNT_POINT, "fuse", MS_NOSUID | MS_NODEV, opts); |
Brian Swetland | 03ee947 | 2010-08-12 18:01:08 -0700 | [diff] [blame] | 862 | if (res < 0) { |
| 863 | ERROR("cannot mount fuse filesystem (%d)\n", errno); |
| 864 | return -1; |
| 865 | } |
| 866 | |
| 867 | if (setgid(gid) < 0) { |
| 868 | ERROR("cannot setgid!\n"); |
| 869 | return -1; |
| 870 | } |
| 871 | if (setuid(uid) < 0) { |
| 872 | ERROR("cannot setuid!\n"); |
| 873 | return -1; |
| 874 | } |
| 875 | |
| 876 | fuse_init(&fuse, fd, path); |
| 877 | |
| 878 | umask(0); |
| 879 | handle_fuse_requests(&fuse); |
| 880 | |
| 881 | return 0; |
| 882 | } |