fs/hfsplus/dir.c

   1 /*
   2  *  linux/fs/hfsplus/dir.c
   3  *
   4  * Copyright (C) 2001
   5  * Brad Boyer (flar@allandria.com)
   6  * (C) 2003 Ardis Technologies <roman@ardistech.com>
   7  *
   8  * Handling of directories
   9  */
  10
  11 #include <linux/errno.h>
  12 #include <linux/fs.h>
  13 #include <linux/slab.h>
  14 #include <linux/random.h>
  15
  16 #include "hfsplus_fs.h"
  17 #include "hfsplus_raw.h"
  18 #include "xattr.h"
  19 #include "acl.h"
  20
  21 static inline void hfsplus_instantiate(struct dentry *dentry,
  22                                        struct inode *inode, u32 cnid)
  23 {
  24         dentry->d_fsdata = (void *)(unsigned long)cnid;
  25         d_instantiate(dentry, inode);
  26 }
  27
  28 /* Find the entry inside dir named dentry->d_name */
  29 static struct dentry *hfsplus_lookup(struct inode *dir, struct dentry *dentry,
  30                                      unsigned int flags)
  31 {
  32         struct inode *inode = NULL;
  33         struct hfs_find_data fd;
  34         struct super_block *sb;
  35         hfsplus_cat_entry entry;
  36         int err;
  37         u32 cnid, linkid = 0;
  38         u16 type;
  39
  40         sb = dir->i_sb;
  41
  42         dentry->d_fsdata = NULL;
  43         err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
  44         if (err)
  45                 return ERR_PTR(err);
  46         hfsplus_cat_build_key(sb, fd.search_key, dir->i_ino, &dentry->d_name);
  47 again:
  48         err = hfs_brec_read(&fd, &entry, sizeof(entry));
  49         if (err) {
  50                 if (err == -ENOENT) {
  51                         hfs_find_exit(&fd);
  52                         /* No such entry */
  53                         inode = NULL;
  54                         goto out;
  55                 }
  56                 goto fail;
  57         }
  58         type = be16_to_cpu(entry.type);
  59         if (type == HFSPLUS_FOLDER) {
  60                 if (fd.entrylength < sizeof(struct hfsplus_cat_folder)) {
  61                         err = -EIO;
  62                         goto fail;
  63                 }
  64                 cnid = be32_to_cpu(entry.folder.id);
  65                 dentry->d_fsdata = (void *)(unsigned long)cnid;
  66         } else if (type == HFSPLUS_FILE) {
  67                 if (fd.entrylength < sizeof(struct hfsplus_cat_file)) {
  68                         err = -EIO;
  69                         goto fail;
  70                 }
  71                 cnid = be32_to_cpu(entry.file.id);
  72                 if (entry.file.user_info.fdType ==
  73                                 cpu_to_be32(HFSP_HARDLINK_TYPE) &&
  74                                 entry.file.user_info.fdCreator ==
  75                                 cpu_to_be32(HFSP_HFSPLUS_CREATOR) &&
  76                                 (entry.file.create_date ==
  77                                         HFSPLUS_I(HFSPLUS_SB(sb)->hidden_dir)->
  78                                                 create_date ||
  79                                 entry.file.create_date ==
  80                                         HFSPLUS_I(sb->s_root->d_inode)->
  81                                                 create_date) &&
  82                                 HFSPLUS_SB(sb)->hidden_dir) {
  83                         struct qstr str;
  84                         char name[32];
  85
  86                         if (dentry->d_fsdata) {
  87                                 /*
  88                                  * We found a link pointing to another link,
  89                                  * so ignore it and treat it as regular file.
  90                                  */
  91                                 cnid = (unsigned long)dentry->d_fsdata;
  92                                 linkid = 0;
  93                         } else {
  94                                 dentry->d_fsdata = (void *)(unsigned long)cnid;
  95                                 linkid =
  96                                         be32_to_cpu(entry.file.permissions.dev);
  97                                 str.len = sprintf(name, "iNode%d", linkid);
  98                                 str.name = name;
  99                                 hfsplus_cat_build_key(sb, fd.search_key,
 100                                         HFSPLUS_SB(sb)->hidden_dir->i_ino,
 101                                         &str);
 102                                 goto again;
 103                         }
 104                 } else if (!dentry->d_fsdata)
 105                         dentry->d_fsdata = (void *)(unsigned long)cnid;
 106         } else {
 107                 pr_err("invalid catalog entry type in lookup\n");
 108                 err = -EIO;
 109                 goto fail;
 110         }
 111         hfs_find_exit(&fd);
 112         inode = hfsplus_iget(dir->i_sb, cnid);
 113         if (IS_ERR(inode))
 114                 return ERR_CAST(inode);
 115         if (S_ISREG(inode->i_mode))
 116                 HFSPLUS_I(inode)->linkid = linkid;
 117 out:
 118         d_add(dentry, inode);
 119         return NULL;
 120 fail:
 121         hfs_find_exit(&fd);
 122         return ERR_PTR(err);
 123 }
 124
 125 static int hfsplus_readdir(struct file *file, struct dir_context *ctx)
 126 {
 127         struct inode *inode = file_inode(file);
 128         struct super_block *sb = inode->i_sb;
 129         int len, err;
 130         char strbuf[HFSPLUS_MAX_STRLEN + 1];
 131         hfsplus_cat_entry entry;
 132         struct hfs_find_data fd;
 133         struct hfsplus_readdir_data *rd;
 134         u16 type;
 135
 136         if (file->f_pos >= inode->i_size)
 137                 return 0;
 138
 139         err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
 140         if (err)
 141                 return err;
 142         hfsplus_cat_build_key(sb, fd.search_key, inode->i_ino, NULL);
 143         err = hfs_brec_find(&fd, hfs_find_rec_by_key);
 144         if (err)
 145                 goto out;
 146
 147         if (ctx->pos == 0) {
 148                 /* This is completely artificial... */
 149                 if (!dir_emit_dot(file, ctx))
 150                         goto out;
 151                 ctx->pos = 1;
 152         }
 153         if (ctx->pos == 1) {
 154                 if (fd.entrylength > sizeof(entry) || fd.entrylength < 0) {
 155                         err = -EIO;
 156                         goto out;
 157                 }
 158
 159                 hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
 160                         fd.entrylength);
 161                 if (be16_to_cpu(entry.type) != HFSPLUS_FOLDER_THREAD) {
 162                         pr_err("bad catalog folder thread\n");
 163                         err = -EIO;
 164                         goto out;
 165                 }
 166                 if (fd.entrylength < HFSPLUS_MIN_THREAD_SZ) {
 167                         pr_err("truncated catalog thread\n");
 168                         err = -EIO;
 169                         goto out;
 170                 }
 171                 if (!dir_emit(ctx, "..", 2,
 172                             be32_to_cpu(entry.thread.parentID), DT_DIR))
 173                         goto out;
 174                 ctx->pos = 2;
 175         }
 176         if (ctx->pos >= inode->i_size)
 177                 goto out;
 178         err = hfs_brec_goto(&fd, ctx->pos - 1);
 179         if (err)
 180                 goto out;
 181         for (;;) {
 182                 if (be32_to_cpu(fd.key->cat.parent) != inode->i_ino) {
 183                         pr_err("walked past end of dir\n");
 184                         err = -EIO;
 185                         goto out;
 186                 }
 187
 188                 if (fd.entrylength > sizeof(entry) || fd.entrylength < 0) {
 189                         err = -EIO;
 190                         goto out;
 191                 }
 192
 193                 hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
 194                         fd.entrylength);
 195                 type = be16_to_cpu(entry.type);
 196                 len = HFSPLUS_MAX_STRLEN;
 197                 err = hfsplus_uni2asc(sb, &fd.key->cat.name, strbuf, &len);
 198                 if (err)
 199                         goto out;
 200                 if (type == HFSPLUS_FOLDER) {
 201                         if (fd.entrylength <
 202                                         sizeof(struct hfsplus_cat_folder)) {
 203                                 pr_err("small dir entry\n");
 204                                 err = -EIO;
 205                                 goto out;
 206                         }
 207                         if (HFSPLUS_SB(sb)->hidden_dir &&
 208                             HFSPLUS_SB(sb)->hidden_dir->i_ino ==
 209                                         be32_to_cpu(entry.folder.id))
 210                                 goto next;
 211                         if (!dir_emit(ctx, strbuf, len,
 212                                     be32_to_cpu(entry.folder.id), DT_DIR))
 213                                 break;
 214                 } else if (type == HFSPLUS_FILE) {
 215                         if (fd.entrylength < sizeof(struct hfsplus_cat_file)) {
 216                                 pr_err("small file entry\n");
 217                                 err = -EIO;
 218                                 goto out;
 219                         }
 220                         if (!dir_emit(ctx, strbuf, len,
 221                                     be32_to_cpu(entry.file.id), DT_REG))
 222                                 break;
 223                 } else {
 224                         pr_err("bad catalog entry type\n");
 225                         err = -EIO;
 226                         goto out;
 227                 }
 228 next:
 229                 ctx->pos++;
 230                 if (ctx->pos >= inode->i_size)
 231                         goto out;
 232                 err = hfs_brec_goto(&fd, 1);
 233                 if (err)
 234                         goto out;
 235         }
 236         rd = file->private_data;
 237         if (!rd) {
 238                 rd = kmalloc(sizeof(struct hfsplus_readdir_data), GFP_KERNEL);
 239                 if (!rd) {
 240                         err = -ENOMEM;
 241                         goto out;
 242                 }
 243                 file->private_data = rd;
 244                 rd->file = file;
 245                 list_add(&rd->list, &HFSPLUS_I(inode)->open_dir_list);
 246         }
 247         memcpy(&rd->key, fd.key, sizeof(struct hfsplus_cat_key));
 248 out:
 249         hfs_find_exit(&fd);
 250         return err;
 251 }
 252
 253 static int hfsplus_dir_release(struct inode *inode, struct file *file)
 254 {
 255         struct hfsplus_readdir_data *rd = file->private_data;
 256         if (rd) {
 257                 mutex_lock(&inode->i_mutex);
 258                 list_del(&rd->list);
 259                 mutex_unlock(&inode->i_mutex);
 260                 kfree(rd);
 261         }
 262         return 0;
 263 }
 264
 265 static int hfsplus_link(struct dentry *src_dentry, struct inode *dst_dir,
 266                         struct dentry *dst_dentry)
 267 {
 268         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dst_dir->i_sb);
 269         struct inode *inode = src_dentry->d_inode;
 270         struct inode *src_dir = src_dentry->d_parent->d_inode;
 271         struct qstr str;
 272         char name[32];
 273         u32 cnid, id;
 274         int res;
 275
 276         if (HFSPLUS_IS_RSRC(inode))
 277                 return -EPERM;
 278         if (!S_ISREG(inode->i_mode))
 279                 return -EPERM;
 280
 281         mutex_lock(&sbi->vh_mutex);
 282         if (inode->i_ino == (u32)(unsigned long)src_dentry->d_fsdata) {
 283                 for (;;) {
 284                         get_random_bytes(&id, sizeof(cnid));
 285                         id &= 0x3fffffff;
 286                         str.name = name;
 287                         str.len = sprintf(name, "iNode%d", id);
 288                         res = hfsplus_rename_cat(inode->i_ino,
 289                                                  src_dir, &src_dentry->d_name,
 290                                                  sbi->hidden_dir, &str);
 291                         if (!res)
 292                                 break;
 293                         if (res != -EEXIST)
 294                                 goto out;
 295                 }
 296                 HFSPLUS_I(inode)->linkid = id;
 297                 cnid = sbi->next_cnid++;
 298                 src_dentry->d_fsdata = (void *)(unsigned long)cnid;
 299                 res = hfsplus_create_cat(cnid, src_dir,
 300                         &src_dentry->d_name, inode);
 301                 if (res)
 302                         /* panic? */
 303                         goto out;
 304                 sbi->file_count++;
 305         }
 306         cnid = sbi->next_cnid++;
 307         res = hfsplus_create_cat(cnid, dst_dir, &dst_dentry->d_name, inode);
 308         if (res)
 309                 goto out;
 310
 311         inc_nlink(inode);
 312         hfsplus_instantiate(dst_dentry, inode, cnid);
 313         ihold(inode);
 314         inode->i_ctime = CURRENT_TIME_SEC;
 315         mark_inode_dirty(inode);
 316         sbi->file_count++;
 317         hfsplus_mark_mdb_dirty(dst_dir->i_sb);
 318 out:
 319         mutex_unlock(&sbi->vh_mutex);
 320         return res;
 321 }
 322
 323 static int hfsplus_unlink(struct inode *dir, struct dentry *dentry)
 324 {
 325         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 326         struct inode *inode = dentry->d_inode;
 327         struct qstr str;
 328         char name[32];
 329         u32 cnid;
 330         int res;
 331
 332         if (HFSPLUS_IS_RSRC(inode))
 333                 return -EPERM;
 334
 335         mutex_lock(&sbi->vh_mutex);
 336         cnid = (u32)(unsigned long)dentry->d_fsdata;
 337         if (inode->i_ino == cnid &&
 338             atomic_read(&HFSPLUS_I(inode)->opencnt)) {
 339                 str.name = name;
 340                 str.len = sprintf(name, "temp%lu", inode->i_ino);
 341                 res = hfsplus_rename_cat(inode->i_ino,
 342                                          dir, &dentry->d_name,
 343                                          sbi->hidden_dir, &str);
 344                 if (!res) {
 345                         inode->i_flags |= S_DEAD;
 346                         drop_nlink(inode);
 347                 }
 348                 goto out;
 349         }
 350         res = hfsplus_delete_cat(cnid, dir, &dentry->d_name);
 351         if (res)
 352                 goto out;
 353
 354         if (inode->i_nlink > 0)
 355                 drop_nlink(inode);
 356         if (inode->i_ino == cnid)
 357                 clear_nlink(inode);
 358         if (!inode->i_nlink) {
 359                 if (inode->i_ino != cnid) {
 360                         sbi->file_count--;
 361                         if (!atomic_read(&HFSPLUS_I(inode)->opencnt)) {
 362                                 res = hfsplus_delete_cat(inode->i_ino,
 363                                                          sbi->hidden_dir,
 364                                                          NULL);
 365                                 if (!res)
 366                                         hfsplus_delete_inode(inode);
 367                         } else
 368                                 inode->i_flags |= S_DEAD;
 369                 } else
 370                         hfsplus_delete_inode(inode);
 371         } else
 372                 sbi->file_count--;
 373         inode->i_ctime = CURRENT_TIME_SEC;
 374         mark_inode_dirty(inode);
 375 out:
 376         mutex_unlock(&sbi->vh_mutex);
 377         return res;
 378 }
 379
 380 static int hfsplus_rmdir(struct inode *dir, struct dentry *dentry)
 381 {
 382         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 383         struct inode *inode = dentry->d_inode;
 384         int res;
 385
 386         if (inode->i_size != 2)
 387                 return -ENOTEMPTY;
 388
 389         mutex_lock(&sbi->vh_mutex);
 390         res = hfsplus_delete_cat(inode->i_ino, dir, &dentry->d_name);
 391         if (res)
 392                 goto out;
 393         clear_nlink(inode);
 394         inode->i_ctime = CURRENT_TIME_SEC;
 395         hfsplus_delete_inode(inode);
 396         mark_inode_dirty(inode);
 397 out:
 398         mutex_unlock(&sbi->vh_mutex);
 399         return res;
 400 }
 401
 402 static int hfsplus_symlink(struct inode *dir, struct dentry *dentry,
 403                            const char *symname)
 404 {
 405         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 406         struct inode *inode;
 407         int res = -ENOSPC;
 408
 409         mutex_lock(&sbi->vh_mutex);
 410         inode = hfsplus_new_inode(dir->i_sb, S_IFLNK | S_IRWXUGO);
 411         if (!inode)
 412                 goto out;
 413
 414         res = page_symlink(inode, symname, strlen(symname) + 1);
 415         if (res)
 416                 goto out_err;
 417
 418         res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
 419         if (res)
 420                 goto out_err;
 421
 422         res = hfsplus_init_inode_security(inode, dir, &dentry->d_name);
 423         if (res == -EOPNOTSUPP)
 424                 res = 0; /* Operation is not supported. */
 425         else if (res) {
 426                 /* Try to delete anyway without error analysis. */
 427                 hfsplus_delete_cat(inode->i_ino, dir, &dentry->d_name);
 428                 goto out_err;
 429         }
 430
 431         hfsplus_instantiate(dentry, inode, inode->i_ino);
 432         mark_inode_dirty(inode);
 433         goto out;
 434
 435 out_err:
 436         clear_nlink(inode);
 437         hfsplus_delete_inode(inode);
 438         iput(inode);
 439 out:
 440         mutex_unlock(&sbi->vh_mutex);
 441         return res;
 442 }
 443
 444 static int hfsplus_mknod(struct inode *dir, struct dentry *dentry,
 445                          umode_t mode, dev_t rdev)
 446 {
 447         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 448         struct inode *inode;
 449         int res = -ENOSPC;
 450
 451         mutex_lock(&sbi->vh_mutex);
 452         inode = hfsplus_new_inode(dir->i_sb, mode);
 453         if (!inode)
 454                 goto out;
 455
 456         if (S_ISBLK(mode) || S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode))
 457                 init_special_inode(inode, mode, rdev);
 458
 459         res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
 460         if (res)
 461                 goto failed_mknod;
 462
 463         res = hfsplus_init_inode_security(inode, dir, &dentry->d_name);
 464         if (res == -EOPNOTSUPP)
 465                 res = 0; /* Operation is not supported. */
 466         else if (res) {
 467                 /* Try to delete anyway without error analysis. */
 468                 hfsplus_delete_cat(inode->i_ino, dir, &dentry->d_name);
 469                 goto failed_mknod;
 470         }
 471
 472         hfsplus_instantiate(dentry, inode, inode->i_ino);
 473         mark_inode_dirty(inode);
 474         goto out;
 475
 476 failed_mknod:
 477         clear_nlink(inode);
 478         hfsplus_delete_inode(inode);
 479         iput(inode);
 480 out:
 481         mutex_unlock(&sbi->vh_mutex);
 482         return res;
 483 }
 484
 485 static int hfsplus_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 486                           bool excl)
 487 {
 488         return hfsplus_mknod(dir, dentry, mode, 0);
 489 }
 490
 491 static int hfsplus_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 492 {
 493         return hfsplus_mknod(dir, dentry, mode | S_IFDIR, 0);
 494 }
 495
 496 static int hfsplus_rename(struct inode *old_dir, struct dentry *old_dentry,
 497                           struct inode *new_dir, struct dentry *new_dentry)
 498 {
 499         int res;
 500
 501         /* Unlink destination if it already exists */
 502         if (new_dentry->d_inode) {
 503                 if (S_ISDIR(new_dentry->d_inode->i_mode))
 504                         res = hfsplus_rmdir(new_dir, new_dentry);
 505                 else
 506                         res = hfsplus_unlink(new_dir, new_dentry);
 507                 if (res)
 508                         return res;
 509         }
 510
 511         res = hfsplus_rename_cat((u32)(unsigned long)old_dentry->d_fsdata,
 512                                  old_dir, &old_dentry->d_name,
 513                                  new_dir, &new_dentry->d_name);
 514         if (!res)
 515                 new_dentry->d_fsdata = old_dentry->d_fsdata;
 516         return res;
 517 }
 518
 519 const struct inode_operations hfsplus_dir_inode_operations = {
 520         .lookup                 = hfsplus_lookup,
 521         .create                 = hfsplus_create,
 522         .link                   = hfsplus_link,
 523         .unlink                 = hfsplus_unlink,
 524         .mkdir                  = hfsplus_mkdir,
 525         .rmdir                  = hfsplus_rmdir,
 526         .symlink                = hfsplus_symlink,
 527         .mknod                  = hfsplus_mknod,
 528         .rename                 = hfsplus_rename,
 529         .setxattr               = generic_setxattr,
 530         .getxattr               = generic_getxattr,
 531         .listxattr              = hfsplus_listxattr,
 532         .removexattr            = hfsplus_removexattr,
 533 #ifdef CONFIG_HFSPLUS_FS_POSIX_ACL
 534         .get_acl                = hfsplus_get_posix_acl,
 535 #endif
 536 };
 537
 538 const struct file_operations hfsplus_dir_operations = {
 539         .fsync          = hfsplus_file_fsync,
 540         .read           = generic_read_dir,
 541         .iterate        = hfsplus_readdir,
 542         .unlocked_ioctl = hfsplus_ioctl,
 543         .llseek         = generic_file_llseek,
 544         .release        = hfsplus_dir_release,
 545 };