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 #include <linux/nls.h>
  16
  17 #include "hfsplus_fs.h"
  18 #include "hfsplus_raw.h"
  19 #include "xattr.h"
  20 #include "acl.h"
  21
  22 static inline void hfsplus_instantiate(struct dentry *dentry,
  23                                        struct inode *inode, u32 cnid)
  24 {
  25         dentry->d_fsdata = (void *)(unsigned long)cnid;
  26         d_instantiate(dentry, inode);
  27 }
  28
  29 /* Find the entry inside dir named dentry->d_name */
  30 static struct dentry *hfsplus_lookup(struct inode *dir, struct dentry *dentry,
  31                                      unsigned int flags)
  32 {
  33         struct inode *inode = NULL;
  34         struct hfs_find_data fd;
  35         struct super_block *sb;
  36         hfsplus_cat_entry entry;
  37         int err;
  38         u32 cnid, linkid = 0;
  39         u16 type;
  40
  41         sb = dir->i_sb;
  42
  43         dentry->d_fsdata = NULL;
  44         err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
  45         if (err)
  46                 return ERR_PTR(err);
  47         hfsplus_cat_build_key(sb, fd.search_key, dir->i_ino, &dentry->d_name);
  48 again:
  49         err = hfs_brec_read(&fd, &entry, sizeof(entry));
  50         if (err) {
  51                 if (err == -ENOENT) {
  52                         hfs_find_exit(&fd);
  53                         /* No such entry */
  54                         inode = NULL;
  55                         goto out;
  56                 }
  57                 goto fail;
  58         }
  59         type = be16_to_cpu(entry.type);
  60         if (type == HFSPLUS_FOLDER) {
  61                 if (fd.entrylength < sizeof(struct hfsplus_cat_folder)) {
  62                         err = -EIO;
  63                         goto fail;
  64                 }
  65                 cnid = be32_to_cpu(entry.folder.id);
  66                 dentry->d_fsdata = (void *)(unsigned long)cnid;
  67         } else if (type == HFSPLUS_FILE) {
  68                 if (fd.entrylength < sizeof(struct hfsplus_cat_file)) {
  69                         err = -EIO;
  70                         goto fail;
  71                 }
  72                 cnid = be32_to_cpu(entry.file.id);
  73                 if (entry.file.user_info.fdType ==
  74                                 cpu_to_be32(HFSP_HARDLINK_TYPE) &&
  75                                 entry.file.user_info.fdCreator ==
  76                                 cpu_to_be32(HFSP_HFSPLUS_CREATOR) &&
  77                                 (entry.file.create_date ==
  78                                         HFSPLUS_I(HFSPLUS_SB(sb)->hidden_dir)->
  79                                                 create_date ||
  80                                 entry.file.create_date ==
  81                                         HFSPLUS_I(sb->s_root->d_inode)->
  82                                                 create_date) &&
  83                                 HFSPLUS_SB(sb)->hidden_dir) {
  84                         struct qstr str;
  85                         char name[32];
  86
  87                         if (dentry->d_fsdata) {
  88                                 /*
  89                                  * We found a link pointing to another link,
  90                                  * so ignore it and treat it as regular file.
  91                                  */
  92                                 cnid = (unsigned long)dentry->d_fsdata;
  93                                 linkid = 0;
  94                         } else {
  95                                 dentry->d_fsdata = (void *)(unsigned long)cnid;
  96                                 linkid =
  97                                         be32_to_cpu(entry.file.permissions.dev);
  98                                 str.len = sprintf(name, "iNode%d", linkid);
  99                                 str.name = name;
 100                                 hfsplus_cat_build_key(sb, fd.search_key,
 101                                         HFSPLUS_SB(sb)->hidden_dir->i_ino,
 102                                         &str);
 103                                 goto again;
 104                         }
 105                 } else if (!dentry->d_fsdata)
 106                         dentry->d_fsdata = (void *)(unsigned long)cnid;
 107         } else {
 108                 pr_err("invalid catalog entry type in lookup\n");
 109                 err = -EIO;
 110                 goto fail;
 111         }
 112         hfs_find_exit(&fd);
 113         inode = hfsplus_iget(dir->i_sb, cnid);
 114         if (IS_ERR(inode))
 115                 return ERR_CAST(inode);
 116         if (S_ISREG(inode->i_mode))
 117                 HFSPLUS_I(inode)->linkid = linkid;
 118 out:
 119         d_add(dentry, inode);
 120         return NULL;
 121 fail:
 122         hfs_find_exit(&fd);
 123         return ERR_PTR(err);
 124 }
 125
 126 static int hfsplus_readdir(struct file *file, struct dir_context *ctx)
 127 {
 128         struct inode *inode = file_inode(file);
 129         struct super_block *sb = inode->i_sb;
 130         int len, err;
 131         char *strbuf;
 132         hfsplus_cat_entry entry;
 133         struct hfs_find_data fd;
 134         struct hfsplus_readdir_data *rd;
 135         u16 type;
 136
 137         if (file->f_pos >= inode->i_size)
 138                 return 0;
 139
 140         err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
 141         if (err)
 142                 return err;
 143         strbuf = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_MAX_STRLEN + 1, GFP_KERNEL);
 144         if (!strbuf) {
 145                 err = -ENOMEM;
 146                 goto out;
 147         }
 148         hfsplus_cat_build_key(sb, fd.search_key, inode->i_ino, NULL);
 149         err = hfs_brec_find(&fd, hfs_find_rec_by_key);
 150         if (err)
 151                 goto out;
 152
 153         if (ctx->pos == 0) {
 154                 /* This is completely artificial... */
 155                 if (!dir_emit_dot(file, ctx))
 156                         goto out;
 157                 ctx->pos = 1;
 158         }
 159         if (ctx->pos == 1) {
 160                 if (fd.entrylength > sizeof(entry) || fd.entrylength < 0) {
 161                         err = -EIO;
 162                         goto out;
 163                 }
 164
 165                 hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
 166                         fd.entrylength);
 167                 if (be16_to_cpu(entry.type) != HFSPLUS_FOLDER_THREAD) {
 168                         pr_err("bad catalog folder thread\n");
 169                         err = -EIO;
 170                         goto out;
 171                 }
 172                 if (fd.entrylength < HFSPLUS_MIN_THREAD_SZ) {
 173                         pr_err("truncated catalog thread\n");
 174                         err = -EIO;
 175                         goto out;
 176                 }
 177                 if (!dir_emit(ctx, "..", 2,
 178                             be32_to_cpu(entry.thread.parentID), DT_DIR))
 179                         goto out;
 180                 ctx->pos = 2;
 181         }
 182         if (ctx->pos >= inode->i_size)
 183                 goto out;
 184         err = hfs_brec_goto(&fd, ctx->pos - 1);
 185         if (err)
 186                 goto out;
 187         for (;;) {
 188                 if (be32_to_cpu(fd.key->cat.parent) != inode->i_ino) {
 189                         pr_err("walked past end of dir\n");
 190                         err = -EIO;
 191                         goto out;
 192                 }
 193
 194                 if (fd.entrylength > sizeof(entry) || fd.entrylength < 0) {
 195                         err = -EIO;
 196                         goto out;
 197                 }
 198
 199                 hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
 200                         fd.entrylength);
 201                 type = be16_to_cpu(entry.type);
 202                 len = NLS_MAX_CHARSET_SIZE * HFSPLUS_MAX_STRLEN;
 203                 err = hfsplus_uni2asc(sb, &fd.key->cat.name, strbuf, &len);
 204                 if (err)
 205                         goto out;
 206                 if (type == HFSPLUS_FOLDER) {
 207                         if (fd.entrylength <
 208                                         sizeof(struct hfsplus_cat_folder)) {
 209                                 pr_err("small dir entry\n");
 210                                 err = -EIO;
 211                                 goto out;
 212                         }
 213                         if (HFSPLUS_SB(sb)->hidden_dir &&
 214                             HFSPLUS_SB(sb)->hidden_dir->i_ino ==
 215                                         be32_to_cpu(entry.folder.id))
 216                                 goto next;
 217                         if (!dir_emit(ctx, strbuf, len,
 218                                     be32_to_cpu(entry.folder.id), DT_DIR))
 219                                 break;
 220                 } else if (type == HFSPLUS_FILE) {
 221                         u16 mode;
 222                         unsigned type = DT_UNKNOWN;
 223
 224                         if (fd.entrylength < sizeof(struct hfsplus_cat_file)) {
 225                                 pr_err("small file entry\n");
 226                                 err = -EIO;
 227                                 goto out;
 228                         }
 229
 230                         mode = be16_to_cpu(entry.file.permissions.mode);
 231                         if (S_ISREG(mode))
 232                                 type = DT_REG;
 233                         else if (S_ISLNK(mode))
 234                                 type = DT_LNK;
 235                         else if (S_ISFIFO(mode))
 236                                 type = DT_FIFO;
 237                         else if (S_ISCHR(mode))
 238                                 type = DT_CHR;
 239                         else if (S_ISBLK(mode))
 240                                 type = DT_BLK;
 241                         else if (S_ISSOCK(mode))
 242                                 type = DT_SOCK;
 243
 244                         if (!dir_emit(ctx, strbuf, len,
 245                                       be32_to_cpu(entry.file.id), type))
 246                                 break;
 247                 } else {
 248                         pr_err("bad catalog entry type\n");
 249                         err = -EIO;
 250                         goto out;
 251                 }
 252 next:
 253                 ctx->pos++;
 254                 if (ctx->pos >= inode->i_size)
 255                         goto out;
 256                 err = hfs_brec_goto(&fd, 1);
 257                 if (err)
 258                         goto out;
 259         }
 260         rd = file->private_data;
 261         if (!rd) {
 262                 rd = kmalloc(sizeof(struct hfsplus_readdir_data), GFP_KERNEL);
 263                 if (!rd) {
 264                         err = -ENOMEM;
 265                         goto out;
 266                 }
 267                 file->private_data = rd;
 268                 rd->file = file;
 269                 list_add(&rd->list, &HFSPLUS_I(inode)->open_dir_list);
 270         }
 271         memcpy(&rd->key, fd.key, sizeof(struct hfsplus_cat_key));
 272 out:
 273         kfree(strbuf);
 274         hfs_find_exit(&fd);
 275         return err;
 276 }
 277
 278 static int hfsplus_dir_release(struct inode *inode, struct file *file)
 279 {
 280         struct hfsplus_readdir_data *rd = file->private_data;
 281         if (rd) {
 282                 mutex_lock(&inode->i_mutex);
 283                 list_del(&rd->list);
 284                 mutex_unlock(&inode->i_mutex);
 285                 kfree(rd);
 286         }
 287         return 0;
 288 }
 289
 290 static int hfsplus_link(struct dentry *src_dentry, struct inode *dst_dir,
 291                         struct dentry *dst_dentry)
 292 {
 293         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dst_dir->i_sb);
 294         struct inode *inode = src_dentry->d_inode;
 295         struct inode *src_dir = src_dentry->d_parent->d_inode;
 296         struct qstr str;
 297         char name[32];
 298         u32 cnid, id;
 299         int res;
 300
 301         if (HFSPLUS_IS_RSRC(inode))
 302                 return -EPERM;
 303         if (!S_ISREG(inode->i_mode))
 304                 return -EPERM;
 305
 306         mutex_lock(&sbi->vh_mutex);
 307         if (inode->i_ino == (u32)(unsigned long)src_dentry->d_fsdata) {
 308                 for (;;) {
 309                         get_random_bytes(&id, sizeof(cnid));
 310                         id &= 0x3fffffff;
 311                         str.name = name;
 312                         str.len = sprintf(name, "iNode%d", id);
 313                         res = hfsplus_rename_cat(inode->i_ino,
 314                                                  src_dir, &src_dentry->d_name,
 315                                                  sbi->hidden_dir, &str);
 316                         if (!res)
 317                                 break;
 318                         if (res != -EEXIST)
 319                                 goto out;
 320                 }
 321                 HFSPLUS_I(inode)->linkid = id;
 322                 cnid = sbi->next_cnid++;
 323                 src_dentry->d_fsdata = (void *)(unsigned long)cnid;
 324                 res = hfsplus_create_cat(cnid, src_dir,
 325                         &src_dentry->d_name, inode);
 326                 if (res)
 327                         /* panic? */
 328                         goto out;
 329                 sbi->file_count++;
 330         }
 331         cnid = sbi->next_cnid++;
 332         res = hfsplus_create_cat(cnid, dst_dir, &dst_dentry->d_name, inode);
 333         if (res)
 334                 goto out;
 335
 336         inc_nlink(inode);
 337         hfsplus_instantiate(dst_dentry, inode, cnid);
 338         ihold(inode);
 339         inode->i_ctime = CURRENT_TIME_SEC;
 340         mark_inode_dirty(inode);
 341         sbi->file_count++;
 342         hfsplus_mark_mdb_dirty(dst_dir->i_sb);
 343 out:
 344         mutex_unlock(&sbi->vh_mutex);
 345         return res;
 346 }
 347
 348 static int hfsplus_unlink(struct inode *dir, struct dentry *dentry)
 349 {
 350         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 351         struct inode *inode = dentry->d_inode;
 352         struct qstr str;
 353         char name[32];
 354         u32 cnid;
 355         int res;
 356
 357         if (HFSPLUS_IS_RSRC(inode))
 358                 return -EPERM;
 359
 360         mutex_lock(&sbi->vh_mutex);
 361         cnid = (u32)(unsigned long)dentry->d_fsdata;
 362         if (inode->i_ino == cnid &&
 363             atomic_read(&HFSPLUS_I(inode)->opencnt)) {
 364                 str.name = name;
 365                 str.len = sprintf(name, "temp%lu", inode->i_ino);
 366                 res = hfsplus_rename_cat(inode->i_ino,
 367                                          dir, &dentry->d_name,
 368                                          sbi->hidden_dir, &str);
 369                 if (!res) {
 370                         inode->i_flags |= S_DEAD;
 371                         drop_nlink(inode);
 372                 }
 373                 goto out;
 374         }
 375         res = hfsplus_delete_cat(cnid, dir, &dentry->d_name);
 376         if (res)
 377                 goto out;
 378
 379         if (inode->i_nlink > 0)
 380                 drop_nlink(inode);
 381         if (inode->i_ino == cnid)
 382                 clear_nlink(inode);
 383         if (!inode->i_nlink) {
 384                 if (inode->i_ino != cnid) {
 385                         sbi->file_count--;
 386                         if (!atomic_read(&HFSPLUS_I(inode)->opencnt)) {
 387                                 res = hfsplus_delete_cat(inode->i_ino,
 388                                                          sbi->hidden_dir,
 389                                                          NULL);
 390                                 if (!res)
 391                                         hfsplus_delete_inode(inode);
 392                         } else
 393                                 inode->i_flags |= S_DEAD;
 394                 } else
 395                         hfsplus_delete_inode(inode);
 396         } else
 397                 sbi->file_count--;
 398         inode->i_ctime = CURRENT_TIME_SEC;
 399         mark_inode_dirty(inode);
 400 out:
 401         mutex_unlock(&sbi->vh_mutex);
 402         return res;
 403 }
 404
 405 static int hfsplus_rmdir(struct inode *dir, struct dentry *dentry)
 406 {
 407         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 408         struct inode *inode = dentry->d_inode;
 409         int res;
 410
 411         if (inode->i_size != 2)
 412                 return -ENOTEMPTY;
 413
 414         mutex_lock(&sbi->vh_mutex);
 415         res = hfsplus_delete_cat(inode->i_ino, dir, &dentry->d_name);
 416         if (res)
 417                 goto out;
 418         clear_nlink(inode);
 419         inode->i_ctime = CURRENT_TIME_SEC;
 420         hfsplus_delete_inode(inode);
 421         mark_inode_dirty(inode);
 422 out:
 423         mutex_unlock(&sbi->vh_mutex);
 424         return res;
 425 }
 426
 427 static int hfsplus_symlink(struct inode *dir, struct dentry *dentry,
 428                            const char *symname)
 429 {
 430         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 431         struct inode *inode;
 432         int res = -ENOSPC;
 433
 434         mutex_lock(&sbi->vh_mutex);
 435         inode = hfsplus_new_inode(dir->i_sb, S_IFLNK | S_IRWXUGO);
 436         if (!inode)
 437                 goto out;
 438
 439         res = page_symlink(inode, symname, strlen(symname) + 1);
 440         if (res)
 441                 goto out_err;
 442
 443         res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
 444         if (res)
 445                 goto out_err;
 446
 447         res = hfsplus_init_inode_security(inode, dir, &dentry->d_name);
 448         if (res == -EOPNOTSUPP)
 449                 res = 0; /* Operation is not supported. */
 450         else if (res) {
 451                 /* Try to delete anyway without error analysis. */
 452                 hfsplus_delete_cat(inode->i_ino, dir, &dentry->d_name);
 453                 goto out_err;
 454         }
 455
 456         hfsplus_instantiate(dentry, inode, inode->i_ino);
 457         mark_inode_dirty(inode);
 458         goto out;
 459
 460 out_err:
 461         clear_nlink(inode);
 462         hfsplus_delete_inode(inode);
 463         iput(inode);
 464 out:
 465         mutex_unlock(&sbi->vh_mutex);
 466         return res;
 467 }
 468
 469 static int hfsplus_mknod(struct inode *dir, struct dentry *dentry,
 470                          umode_t mode, dev_t rdev)
 471 {
 472         struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb);
 473         struct inode *inode;
 474         int res = -ENOSPC;
 475
 476         mutex_lock(&sbi->vh_mutex);
 477         inode = hfsplus_new_inode(dir->i_sb, mode);
 478         if (!inode)
 479                 goto out;
 480
 481         if (S_ISBLK(mode) || S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode))
 482                 init_special_inode(inode, mode, rdev);
 483
 484         res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode);
 485         if (res)
 486                 goto failed_mknod;
 487
 488         res = hfsplus_init_inode_security(inode, dir, &dentry->d_name);
 489         if (res == -EOPNOTSUPP)
 490                 res = 0; /* Operation is not supported. */
 491         else if (res) {
 492                 /* Try to delete anyway without error analysis. */
 493                 hfsplus_delete_cat(inode->i_ino, dir, &dentry->d_name);
 494                 goto failed_mknod;
 495         }
 496
 497         hfsplus_instantiate(dentry, inode, inode->i_ino);
 498         mark_inode_dirty(inode);
 499         goto out;
 500
 501 failed_mknod:
 502         clear_nlink(inode);
 503         hfsplus_delete_inode(inode);
 504         iput(inode);
 505 out:
 506         mutex_unlock(&sbi->vh_mutex);
 507         return res;
 508 }
 509
 510 static int hfsplus_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 511                           bool excl)
 512 {
 513         return hfsplus_mknod(dir, dentry, mode, 0);
 514 }
 515
 516 static int hfsplus_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 517 {
 518         return hfsplus_mknod(dir, dentry, mode | S_IFDIR, 0);
 519 }
 520
 521 static int hfsplus_rename(struct inode *old_dir, struct dentry *old_dentry,
 522                           struct inode *new_dir, struct dentry *new_dentry)
 523 {
 524         int res;
 525
 526         /* Unlink destination if it already exists */
 527         if (new_dentry->d_inode) {
 528                 if (S_ISDIR(new_dentry->d_inode->i_mode))
 529                         res = hfsplus_rmdir(new_dir, new_dentry);
 530                 else
 531                         res = hfsplus_unlink(new_dir, new_dentry);
 532                 if (res)
 533                         return res;
 534         }
 535
 536         res = hfsplus_rename_cat((u32)(unsigned long)old_dentry->d_fsdata,
 537                                  old_dir, &old_dentry->d_name,
 538                                  new_dir, &new_dentry->d_name);
 539         if (!res)
 540                 new_dentry->d_fsdata = old_dentry->d_fsdata;
 541         return res;
 542 }
 543
 544 const struct inode_operations hfsplus_dir_inode_operations = {
 545         .lookup                 = hfsplus_lookup,
 546         .create                 = hfsplus_create,
 547         .link                   = hfsplus_link,
 548         .unlink                 = hfsplus_unlink,
 549         .mkdir                  = hfsplus_mkdir,
 550         .rmdir                  = hfsplus_rmdir,
 551         .symlink                = hfsplus_symlink,
 552         .mknod                  = hfsplus_mknod,
 553         .rename                 = hfsplus_rename,
 554         .setxattr               = generic_setxattr,
 555         .getxattr               = generic_getxattr,
 556         .listxattr              = hfsplus_listxattr,
 557         .removexattr            = generic_removexattr,
 558 #ifdef CONFIG_HFSPLUS_FS_POSIX_ACL
 559         .get_acl                = hfsplus_get_posix_acl,
 560         .set_acl                = hfsplus_set_posix_acl,
 561 #endif
 562 };
 563
 564 const struct file_operations hfsplus_dir_operations = {
 565         .fsync          = hfsplus_file_fsync,
 566         .read           = generic_read_dir,
 567         .iterate        = hfsplus_readdir,
 568         .unlocked_ioctl = hfsplus_ioctl,
 569         .llseek         = generic_file_llseek,
 570         .release        = hfsplus_dir_release,
 571 };