linux/fs/hfsplus/xattr.c
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   1/*
   2 * linux/fs/hfsplus/xattr.c
   3 *
   4 * Vyacheslav Dubeyko <slava@dubeyko.com>
   5 *
   6 * Logic of processing extended attributes
   7 */
   8
   9#include "hfsplus_fs.h"
  10#include <linux/posix_acl_xattr.h>
  11#include <linux/nls.h>
  12#include "xattr.h"
  13#include "acl.h"
  14
  15static int hfsplus_removexattr(struct inode *inode, const char *name);
  16
  17const struct xattr_handler *hfsplus_xattr_handlers[] = {
  18        &hfsplus_xattr_osx_handler,
  19        &hfsplus_xattr_user_handler,
  20        &hfsplus_xattr_trusted_handler,
  21#ifdef CONFIG_HFSPLUS_FS_POSIX_ACL
  22        &posix_acl_access_xattr_handler,
  23        &posix_acl_default_xattr_handler,
  24#endif
  25        &hfsplus_xattr_security_handler,
  26        NULL
  27};
  28
  29static int strcmp_xattr_finder_info(const char *name)
  30{
  31        if (name) {
  32                return strncmp(name, HFSPLUS_XATTR_FINDER_INFO_NAME,
  33                                sizeof(HFSPLUS_XATTR_FINDER_INFO_NAME));
  34        }
  35        return -1;
  36}
  37
  38static int strcmp_xattr_acl(const char *name)
  39{
  40        if (name) {
  41                return strncmp(name, HFSPLUS_XATTR_ACL_NAME,
  42                                sizeof(HFSPLUS_XATTR_ACL_NAME));
  43        }
  44        return -1;
  45}
  46
  47static bool is_known_namespace(const char *name)
  48{
  49        if (strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN) &&
  50            strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN) &&
  51            strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) &&
  52            strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN))
  53                return false;
  54
  55        return true;
  56}
  57
  58static void hfsplus_init_header_node(struct inode *attr_file,
  59                                        u32 clump_size,
  60                                        char *buf, u16 node_size)
  61{
  62        struct hfs_bnode_desc *desc;
  63        struct hfs_btree_header_rec *head;
  64        u16 offset;
  65        __be16 *rec_offsets;
  66        u32 hdr_node_map_rec_bits;
  67        char *bmp;
  68        u32 used_nodes;
  69        u32 used_bmp_bytes;
  70        u64 tmp;
  71
  72        hfs_dbg(ATTR_MOD, "init_hdr_attr_file: clump %u, node_size %u\n",
  73                clump_size, node_size);
  74
  75        /* The end of the node contains list of record offsets */
  76        rec_offsets = (__be16 *)(buf + node_size);
  77
  78        desc = (struct hfs_bnode_desc *)buf;
  79        desc->type = HFS_NODE_HEADER;
  80        desc->num_recs = cpu_to_be16(HFSPLUS_BTREE_HDR_NODE_RECS_COUNT);
  81        offset = sizeof(struct hfs_bnode_desc);
  82        *--rec_offsets = cpu_to_be16(offset);
  83
  84        head = (struct hfs_btree_header_rec *)(buf + offset);
  85        head->node_size = cpu_to_be16(node_size);
  86        tmp = i_size_read(attr_file);
  87        do_div(tmp, node_size);
  88        head->node_count = cpu_to_be32(tmp);
  89        head->free_nodes = cpu_to_be32(be32_to_cpu(head->node_count) - 1);
  90        head->clump_size = cpu_to_be32(clump_size);
  91        head->attributes |= cpu_to_be32(HFS_TREE_BIGKEYS | HFS_TREE_VARIDXKEYS);
  92        head->max_key_len = cpu_to_be16(HFSPLUS_ATTR_KEYLEN - sizeof(u16));
  93        offset += sizeof(struct hfs_btree_header_rec);
  94        *--rec_offsets = cpu_to_be16(offset);
  95        offset += HFSPLUS_BTREE_HDR_USER_BYTES;
  96        *--rec_offsets = cpu_to_be16(offset);
  97
  98        hdr_node_map_rec_bits = 8 * (node_size - offset - (4 * sizeof(u16)));
  99        if (be32_to_cpu(head->node_count) > hdr_node_map_rec_bits) {
 100                u32 map_node_bits;
 101                u32 map_nodes;
 102
 103                desc->next = cpu_to_be32(be32_to_cpu(head->leaf_tail) + 1);
 104                map_node_bits = 8 * (node_size - sizeof(struct hfs_bnode_desc) -
 105                                        (2 * sizeof(u16)) - 2);
 106                map_nodes = (be32_to_cpu(head->node_count) -
 107                                hdr_node_map_rec_bits +
 108                                (map_node_bits - 1)) / map_node_bits;
 109                be32_add_cpu(&head->free_nodes, 0 - map_nodes);
 110        }
 111
 112        bmp = buf + offset;
 113        used_nodes =
 114                be32_to_cpu(head->node_count) - be32_to_cpu(head->free_nodes);
 115        used_bmp_bytes = used_nodes / 8;
 116        if (used_bmp_bytes) {
 117                memset(bmp, 0xFF, used_bmp_bytes);
 118                bmp += used_bmp_bytes;
 119                used_nodes %= 8;
 120        }
 121        *bmp = ~(0xFF >> used_nodes);
 122        offset += hdr_node_map_rec_bits / 8;
 123        *--rec_offsets = cpu_to_be16(offset);
 124}
 125
 126static int hfsplus_create_attributes_file(struct super_block *sb)
 127{
 128        int err = 0;
 129        struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
 130        struct inode *attr_file;
 131        struct hfsplus_inode_info *hip;
 132        u32 clump_size;
 133        u16 node_size = HFSPLUS_ATTR_TREE_NODE_SIZE;
 134        char *buf;
 135        int index, written;
 136        struct address_space *mapping;
 137        struct page *page;
 138        int old_state = HFSPLUS_EMPTY_ATTR_TREE;
 139
 140        hfs_dbg(ATTR_MOD, "create_attr_file: ino %d\n", HFSPLUS_ATTR_CNID);
 141
 142check_attr_tree_state_again:
 143        switch (atomic_read(&sbi->attr_tree_state)) {
 144        case HFSPLUS_EMPTY_ATTR_TREE:
 145                if (old_state != atomic_cmpxchg(&sbi->attr_tree_state,
 146                                                old_state,
 147                                                HFSPLUS_CREATING_ATTR_TREE))
 148                        goto check_attr_tree_state_again;
 149                break;
 150        case HFSPLUS_CREATING_ATTR_TREE:
 151                /*
 152                 * This state means that another thread is in process
 153                 * of AttributesFile creation. Theoretically, it is
 154                 * possible to be here. But really __setxattr() method
 155                 * first of all calls hfs_find_init() for lookup in
 156                 * B-tree of CatalogFile. This method locks mutex of
 157                 * CatalogFile's B-tree. As a result, if some thread
 158                 * is inside AttributedFile creation operation then
 159                 * another threads will be waiting unlocking of
 160                 * CatalogFile's B-tree's mutex. However, if code will
 161                 * change then we will return error code (-EAGAIN) from
 162                 * here. Really, it means that first try to set of xattr
 163                 * fails with error but second attempt will have success.
 164                 */
 165                return -EAGAIN;
 166        case HFSPLUS_VALID_ATTR_TREE:
 167                return 0;
 168        case HFSPLUS_FAILED_ATTR_TREE:
 169                return -EOPNOTSUPP;
 170        default:
 171                BUG();
 172        }
 173
 174        attr_file = hfsplus_iget(sb, HFSPLUS_ATTR_CNID);
 175        if (IS_ERR(attr_file)) {
 176                pr_err("failed to load attributes file\n");
 177                return PTR_ERR(attr_file);
 178        }
 179
 180        BUG_ON(i_size_read(attr_file) != 0);
 181
 182        hip = HFSPLUS_I(attr_file);
 183
 184        clump_size = hfsplus_calc_btree_clump_size(sb->s_blocksize,
 185                                                    node_size,
 186                                                    sbi->sect_count,
 187                                                    HFSPLUS_ATTR_CNID);
 188
 189        mutex_lock(&hip->extents_lock);
 190        hip->clump_blocks = clump_size >> sbi->alloc_blksz_shift;
 191        mutex_unlock(&hip->extents_lock);
 192
 193        if (sbi->free_blocks <= (hip->clump_blocks << 1)) {
 194                err = -ENOSPC;
 195                goto end_attr_file_creation;
 196        }
 197
 198        while (hip->alloc_blocks < hip->clump_blocks) {
 199                err = hfsplus_file_extend(attr_file, false);
 200                if (unlikely(err)) {
 201                        pr_err("failed to extend attributes file\n");
 202                        goto end_attr_file_creation;
 203                }
 204                hip->phys_size = attr_file->i_size =
 205                        (loff_t)hip->alloc_blocks << sbi->alloc_blksz_shift;
 206                hip->fs_blocks = hip->alloc_blocks << sbi->fs_shift;
 207                inode_set_bytes(attr_file, attr_file->i_size);
 208        }
 209
 210        buf = kzalloc(node_size, GFP_NOFS);
 211        if (!buf) {
 212                pr_err("failed to allocate memory for header node\n");
 213                err = -ENOMEM;
 214                goto end_attr_file_creation;
 215        }
 216
 217        hfsplus_init_header_node(attr_file, clump_size, buf, node_size);
 218
 219        mapping = attr_file->i_mapping;
 220
 221        index = 0;
 222        written = 0;
 223        for (; written < node_size; index++, written += PAGE_SIZE) {
 224                void *kaddr;
 225
 226                page = read_mapping_page(mapping, index, NULL);
 227                if (IS_ERR(page)) {
 228                        err = PTR_ERR(page);
 229                        goto failed_header_node_init;
 230                }
 231
 232                kaddr = kmap_atomic(page);
 233                memcpy(kaddr, buf + written,
 234                        min_t(size_t, PAGE_SIZE, node_size - written));
 235                kunmap_atomic(kaddr);
 236
 237                set_page_dirty(page);
 238                put_page(page);
 239        }
 240
 241        hfsplus_mark_inode_dirty(attr_file, HFSPLUS_I_ATTR_DIRTY);
 242
 243        sbi->attr_tree = hfs_btree_open(sb, HFSPLUS_ATTR_CNID);
 244        if (!sbi->attr_tree)
 245                pr_err("failed to load attributes file\n");
 246
 247failed_header_node_init:
 248        kfree(buf);
 249
 250end_attr_file_creation:
 251        iput(attr_file);
 252
 253        if (!err)
 254                atomic_set(&sbi->attr_tree_state, HFSPLUS_VALID_ATTR_TREE);
 255        else if (err == -ENOSPC)
 256                atomic_set(&sbi->attr_tree_state, HFSPLUS_EMPTY_ATTR_TREE);
 257        else
 258                atomic_set(&sbi->attr_tree_state, HFSPLUS_FAILED_ATTR_TREE);
 259
 260        return err;
 261}
 262
 263int __hfsplus_setxattr(struct inode *inode, const char *name,
 264                        const void *value, size_t size, int flags)
 265{
 266        int err = 0;
 267        struct hfs_find_data cat_fd;
 268        hfsplus_cat_entry entry;
 269        u16 cat_entry_flags, cat_entry_type;
 270        u16 folder_finderinfo_len = sizeof(struct DInfo) +
 271                                        sizeof(struct DXInfo);
 272        u16 file_finderinfo_len = sizeof(struct FInfo) +
 273                                        sizeof(struct FXInfo);
 274
 275        if ((!S_ISREG(inode->i_mode) &&
 276                        !S_ISDIR(inode->i_mode)) ||
 277                                HFSPLUS_IS_RSRC(inode))
 278                return -EOPNOTSUPP;
 279
 280        if (value == NULL)
 281                return hfsplus_removexattr(inode, name);
 282
 283        err = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &cat_fd);
 284        if (err) {
 285                pr_err("can't init xattr find struct\n");
 286                return err;
 287        }
 288
 289        err = hfsplus_find_cat(inode->i_sb, inode->i_ino, &cat_fd);
 290        if (err) {
 291                pr_err("catalog searching failed\n");
 292                goto end_setxattr;
 293        }
 294
 295        if (!strcmp_xattr_finder_info(name)) {
 296                if (flags & XATTR_CREATE) {
 297                        pr_err("xattr exists yet\n");
 298                        err = -EOPNOTSUPP;
 299                        goto end_setxattr;
 300                }
 301                hfs_bnode_read(cat_fd.bnode, &entry, cat_fd.entryoffset,
 302                                        sizeof(hfsplus_cat_entry));
 303                if (be16_to_cpu(entry.type) == HFSPLUS_FOLDER) {
 304                        if (size == folder_finderinfo_len) {
 305                                memcpy(&entry.folder.user_info, value,
 306                                                folder_finderinfo_len);
 307                                hfs_bnode_write(cat_fd.bnode, &entry,
 308                                        cat_fd.entryoffset,
 309                                        sizeof(struct hfsplus_cat_folder));
 310                                hfsplus_mark_inode_dirty(inode,
 311                                                HFSPLUS_I_CAT_DIRTY);
 312                        } else {
 313                                err = -ERANGE;
 314                                goto end_setxattr;
 315                        }
 316                } else if (be16_to_cpu(entry.type) == HFSPLUS_FILE) {
 317                        if (size == file_finderinfo_len) {
 318                                memcpy(&entry.file.user_info, value,
 319                                                file_finderinfo_len);
 320                                hfs_bnode_write(cat_fd.bnode, &entry,
 321                                        cat_fd.entryoffset,
 322                                        sizeof(struct hfsplus_cat_file));
 323                                hfsplus_mark_inode_dirty(inode,
 324                                                HFSPLUS_I_CAT_DIRTY);
 325                        } else {
 326                                err = -ERANGE;
 327                                goto end_setxattr;
 328                        }
 329                } else {
 330                        err = -EOPNOTSUPP;
 331                        goto end_setxattr;
 332                }
 333                goto end_setxattr;
 334        }
 335
 336        if (!HFSPLUS_SB(inode->i_sb)->attr_tree) {
 337                err = hfsplus_create_attributes_file(inode->i_sb);
 338                if (unlikely(err))
 339                        goto end_setxattr;
 340        }
 341
 342        if (hfsplus_attr_exists(inode, name)) {
 343                if (flags & XATTR_CREATE) {
 344                        pr_err("xattr exists yet\n");
 345                        err = -EOPNOTSUPP;
 346                        goto end_setxattr;
 347                }
 348                err = hfsplus_delete_attr(inode, name);
 349                if (err)
 350                        goto end_setxattr;
 351                err = hfsplus_create_attr(inode, name, value, size);
 352                if (err)
 353                        goto end_setxattr;
 354        } else {
 355                if (flags & XATTR_REPLACE) {
 356                        pr_err("cannot replace xattr\n");
 357                        err = -EOPNOTSUPP;
 358                        goto end_setxattr;
 359                }
 360                err = hfsplus_create_attr(inode, name, value, size);
 361                if (err)
 362                        goto end_setxattr;
 363        }
 364
 365        cat_entry_type = hfs_bnode_read_u16(cat_fd.bnode, cat_fd.entryoffset);
 366        if (cat_entry_type == HFSPLUS_FOLDER) {
 367                cat_entry_flags = hfs_bnode_read_u16(cat_fd.bnode,
 368                                    cat_fd.entryoffset +
 369                                    offsetof(struct hfsplus_cat_folder, flags));
 370                cat_entry_flags |= HFSPLUS_XATTR_EXISTS;
 371                if (!strcmp_xattr_acl(name))
 372                        cat_entry_flags |= HFSPLUS_ACL_EXISTS;
 373                hfs_bnode_write_u16(cat_fd.bnode, cat_fd.entryoffset +
 374                                offsetof(struct hfsplus_cat_folder, flags),
 375                                cat_entry_flags);
 376                hfsplus_mark_inode_dirty(inode, HFSPLUS_I_CAT_DIRTY);
 377        } else if (cat_entry_type == HFSPLUS_FILE) {
 378                cat_entry_flags = hfs_bnode_read_u16(cat_fd.bnode,
 379                                    cat_fd.entryoffset +
 380                                    offsetof(struct hfsplus_cat_file, flags));
 381                cat_entry_flags |= HFSPLUS_XATTR_EXISTS;
 382                if (!strcmp_xattr_acl(name))
 383                        cat_entry_flags |= HFSPLUS_ACL_EXISTS;
 384                hfs_bnode_write_u16(cat_fd.bnode, cat_fd.entryoffset +
 385                                    offsetof(struct hfsplus_cat_file, flags),
 386                                    cat_entry_flags);
 387                hfsplus_mark_inode_dirty(inode, HFSPLUS_I_CAT_DIRTY);
 388        } else {
 389                pr_err("invalid catalog entry type\n");
 390                err = -EIO;
 391                goto end_setxattr;
 392        }
 393
 394end_setxattr:
 395        hfs_find_exit(&cat_fd);
 396        return err;
 397}
 398
 399static int name_len(const char *xattr_name, int xattr_name_len)
 400{
 401        int len = xattr_name_len + 1;
 402
 403        if (!is_known_namespace(xattr_name))
 404                len += XATTR_MAC_OSX_PREFIX_LEN;
 405
 406        return len;
 407}
 408
 409static int copy_name(char *buffer, const char *xattr_name, int name_len)
 410{
 411        int len = name_len;
 412        int offset = 0;
 413
 414        if (!is_known_namespace(xattr_name)) {
 415                strncpy(buffer, XATTR_MAC_OSX_PREFIX, XATTR_MAC_OSX_PREFIX_LEN);
 416                offset += XATTR_MAC_OSX_PREFIX_LEN;
 417                len += XATTR_MAC_OSX_PREFIX_LEN;
 418        }
 419
 420        strncpy(buffer + offset, xattr_name, name_len);
 421        memset(buffer + offset + name_len, 0, 1);
 422        len += 1;
 423
 424        return len;
 425}
 426
 427int hfsplus_setxattr(struct dentry *dentry, const char *name,
 428                     const void *value, size_t size, int flags,
 429                     const char *prefix, size_t prefixlen)
 430{
 431        char *xattr_name;
 432        int res;
 433
 434        xattr_name = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN + 1,
 435                GFP_KERNEL);
 436        if (!xattr_name)
 437                return -ENOMEM;
 438        strcpy(xattr_name, prefix);
 439        strcpy(xattr_name + prefixlen, name);
 440        res = __hfsplus_setxattr(d_inode(dentry), xattr_name, value, size,
 441                                 flags);
 442        kfree(xattr_name);
 443        return res;
 444}
 445
 446static ssize_t hfsplus_getxattr_finder_info(struct inode *inode,
 447                                                void *value, size_t size)
 448{
 449        ssize_t res = 0;
 450        struct hfs_find_data fd;
 451        u16 entry_type;
 452        u16 folder_rec_len = sizeof(struct DInfo) + sizeof(struct DXInfo);
 453        u16 file_rec_len = sizeof(struct FInfo) + sizeof(struct FXInfo);
 454        u16 record_len = max(folder_rec_len, file_rec_len);
 455        u8 folder_finder_info[sizeof(struct DInfo) + sizeof(struct DXInfo)];
 456        u8 file_finder_info[sizeof(struct FInfo) + sizeof(struct FXInfo)];
 457
 458        if (size >= record_len) {
 459                res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &fd);
 460                if (res) {
 461                        pr_err("can't init xattr find struct\n");
 462                        return res;
 463                }
 464                res = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
 465                if (res)
 466                        goto end_getxattr_finder_info;
 467                entry_type = hfs_bnode_read_u16(fd.bnode, fd.entryoffset);
 468
 469                if (entry_type == HFSPLUS_FOLDER) {
 470                        hfs_bnode_read(fd.bnode, folder_finder_info,
 471                                fd.entryoffset +
 472                                offsetof(struct hfsplus_cat_folder, user_info),
 473                                folder_rec_len);
 474                        memcpy(value, folder_finder_info, folder_rec_len);
 475                        res = folder_rec_len;
 476                } else if (entry_type == HFSPLUS_FILE) {
 477                        hfs_bnode_read(fd.bnode, file_finder_info,
 478                                fd.entryoffset +
 479                                offsetof(struct hfsplus_cat_file, user_info),
 480                                file_rec_len);
 481                        memcpy(value, file_finder_info, file_rec_len);
 482                        res = file_rec_len;
 483                } else {
 484                        res = -EOPNOTSUPP;
 485                        goto end_getxattr_finder_info;
 486                }
 487        } else
 488                res = size ? -ERANGE : record_len;
 489
 490end_getxattr_finder_info:
 491        if (size >= record_len)
 492                hfs_find_exit(&fd);
 493        return res;
 494}
 495
 496ssize_t __hfsplus_getxattr(struct inode *inode, const char *name,
 497                         void *value, size_t size)
 498{
 499        struct hfs_find_data fd;
 500        hfsplus_attr_entry *entry;
 501        __be32 xattr_record_type;
 502        u32 record_type;
 503        u16 record_length = 0;
 504        ssize_t res = 0;
 505
 506        if ((!S_ISREG(inode->i_mode) &&
 507                        !S_ISDIR(inode->i_mode)) ||
 508                                HFSPLUS_IS_RSRC(inode))
 509                return -EOPNOTSUPP;
 510
 511        if (!strcmp_xattr_finder_info(name))
 512                return hfsplus_getxattr_finder_info(inode, value, size);
 513
 514        if (!HFSPLUS_SB(inode->i_sb)->attr_tree)
 515                return -EOPNOTSUPP;
 516
 517        entry = hfsplus_alloc_attr_entry();
 518        if (!entry) {
 519                pr_err("can't allocate xattr entry\n");
 520                return -ENOMEM;
 521        }
 522
 523        res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->attr_tree, &fd);
 524        if (res) {
 525                pr_err("can't init xattr find struct\n");
 526                goto failed_getxattr_init;
 527        }
 528
 529        res = hfsplus_find_attr(inode->i_sb, inode->i_ino, name, &fd);
 530        if (res) {
 531                if (res == -ENOENT)
 532                        res = -ENODATA;
 533                else
 534                        pr_err("xattr searching failed\n");
 535                goto out;
 536        }
 537
 538        hfs_bnode_read(fd.bnode, &xattr_record_type,
 539                        fd.entryoffset, sizeof(xattr_record_type));
 540        record_type = be32_to_cpu(xattr_record_type);
 541        if (record_type == HFSPLUS_ATTR_INLINE_DATA) {
 542                record_length = hfs_bnode_read_u16(fd.bnode,
 543                                fd.entryoffset +
 544                                offsetof(struct hfsplus_attr_inline_data,
 545                                length));
 546                if (record_length > HFSPLUS_MAX_INLINE_DATA_SIZE) {
 547                        pr_err("invalid xattr record size\n");
 548                        res = -EIO;
 549                        goto out;
 550                }
 551        } else if (record_type == HFSPLUS_ATTR_FORK_DATA ||
 552                        record_type == HFSPLUS_ATTR_EXTENTS) {
 553                pr_err("only inline data xattr are supported\n");
 554                res = -EOPNOTSUPP;
 555                goto out;
 556        } else {
 557                pr_err("invalid xattr record\n");
 558                res = -EIO;
 559                goto out;
 560        }
 561
 562        if (size) {
 563                hfs_bnode_read(fd.bnode, entry, fd.entryoffset,
 564                                offsetof(struct hfsplus_attr_inline_data,
 565                                        raw_bytes) + record_length);
 566        }
 567
 568        if (size >= record_length) {
 569                memcpy(value, entry->inline_data.raw_bytes, record_length);
 570                res = record_length;
 571        } else
 572                res = size ? -ERANGE : record_length;
 573
 574out:
 575        hfs_find_exit(&fd);
 576
 577failed_getxattr_init:
 578        hfsplus_destroy_attr_entry(entry);
 579        return res;
 580}
 581
 582ssize_t hfsplus_getxattr(struct dentry *dentry, const char *name,
 583                         void *value, size_t size,
 584                         const char *prefix, size_t prefixlen)
 585{
 586        int res;
 587        char *xattr_name;
 588
 589        xattr_name = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN + 1,
 590                             GFP_KERNEL);
 591        if (!xattr_name)
 592                return -ENOMEM;
 593
 594        strcpy(xattr_name, prefix);
 595        strcpy(xattr_name + prefixlen, name);
 596
 597        res = __hfsplus_getxattr(d_inode(dentry), xattr_name, value, size);
 598        kfree(xattr_name);
 599        return res;
 600
 601}
 602
 603static inline int can_list(const char *xattr_name)
 604{
 605        if (!xattr_name)
 606                return 0;
 607
 608        return strncmp(xattr_name, XATTR_TRUSTED_PREFIX,
 609                        XATTR_TRUSTED_PREFIX_LEN) ||
 610                                capable(CAP_SYS_ADMIN);
 611}
 612
 613static ssize_t hfsplus_listxattr_finder_info(struct dentry *dentry,
 614                                                char *buffer, size_t size)
 615{
 616        ssize_t res = 0;
 617        struct inode *inode = d_inode(dentry);
 618        struct hfs_find_data fd;
 619        u16 entry_type;
 620        u8 folder_finder_info[sizeof(struct DInfo) + sizeof(struct DXInfo)];
 621        u8 file_finder_info[sizeof(struct FInfo) + sizeof(struct FXInfo)];
 622        unsigned long len, found_bit;
 623        int xattr_name_len, symbols_count;
 624
 625        res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &fd);
 626        if (res) {
 627                pr_err("can't init xattr find struct\n");
 628                return res;
 629        }
 630
 631        res = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
 632        if (res)
 633                goto end_listxattr_finder_info;
 634
 635        entry_type = hfs_bnode_read_u16(fd.bnode, fd.entryoffset);
 636        if (entry_type == HFSPLUS_FOLDER) {
 637                len = sizeof(struct DInfo) + sizeof(struct DXInfo);
 638                hfs_bnode_read(fd.bnode, folder_finder_info,
 639                                fd.entryoffset +
 640                                offsetof(struct hfsplus_cat_folder, user_info),
 641                                len);
 642                found_bit = find_first_bit((void *)folder_finder_info, len*8);
 643        } else if (entry_type == HFSPLUS_FILE) {
 644                len = sizeof(struct FInfo) + sizeof(struct FXInfo);
 645                hfs_bnode_read(fd.bnode, file_finder_info,
 646                                fd.entryoffset +
 647                                offsetof(struct hfsplus_cat_file, user_info),
 648                                len);
 649                found_bit = find_first_bit((void *)file_finder_info, len*8);
 650        } else {
 651                res = -EOPNOTSUPP;
 652                goto end_listxattr_finder_info;
 653        }
 654
 655        if (found_bit >= (len*8))
 656                res = 0;
 657        else {
 658                symbols_count = sizeof(HFSPLUS_XATTR_FINDER_INFO_NAME) - 1;
 659                xattr_name_len =
 660                        name_len(HFSPLUS_XATTR_FINDER_INFO_NAME, symbols_count);
 661                if (!buffer || !size) {
 662                        if (can_list(HFSPLUS_XATTR_FINDER_INFO_NAME))
 663                                res = xattr_name_len;
 664                } else if (can_list(HFSPLUS_XATTR_FINDER_INFO_NAME)) {
 665                        if (size < xattr_name_len)
 666                                res = -ERANGE;
 667                        else {
 668                                res = copy_name(buffer,
 669                                                HFSPLUS_XATTR_FINDER_INFO_NAME,
 670                                                symbols_count);
 671                        }
 672                }
 673        }
 674
 675end_listxattr_finder_info:
 676        hfs_find_exit(&fd);
 677
 678        return res;
 679}
 680
 681ssize_t hfsplus_listxattr(struct dentry *dentry, char *buffer, size_t size)
 682{
 683        ssize_t err;
 684        ssize_t res = 0;
 685        struct inode *inode = d_inode(dentry);
 686        struct hfs_find_data fd;
 687        u16 key_len = 0;
 688        struct hfsplus_attr_key attr_key;
 689        char *strbuf;
 690        int xattr_name_len;
 691
 692        if ((!S_ISREG(inode->i_mode) &&
 693                        !S_ISDIR(inode->i_mode)) ||
 694                                HFSPLUS_IS_RSRC(inode))
 695                return -EOPNOTSUPP;
 696
 697        res = hfsplus_listxattr_finder_info(dentry, buffer, size);
 698        if (res < 0)
 699                return res;
 700        else if (!HFSPLUS_SB(inode->i_sb)->attr_tree)
 701                return (res == 0) ? -EOPNOTSUPP : res;
 702
 703        err = hfs_find_init(HFSPLUS_SB(inode->i_sb)->attr_tree, &fd);
 704        if (err) {
 705                pr_err("can't init xattr find struct\n");
 706                return err;
 707        }
 708
 709        strbuf = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN +
 710                        XATTR_MAC_OSX_PREFIX_LEN + 1, GFP_KERNEL);
 711        if (!strbuf) {
 712                res = -ENOMEM;
 713                goto out;
 714        }
 715
 716        err = hfsplus_find_attr(inode->i_sb, inode->i_ino, NULL, &fd);
 717        if (err) {
 718                if (err == -ENOENT) {
 719                        if (res == 0)
 720                                res = -ENODATA;
 721                        goto end_listxattr;
 722                } else {
 723                        res = err;
 724                        goto end_listxattr;
 725                }
 726        }
 727
 728        for (;;) {
 729                key_len = hfs_bnode_read_u16(fd.bnode, fd.keyoffset);
 730                if (key_len == 0 || key_len > fd.tree->max_key_len) {
 731                        pr_err("invalid xattr key length: %d\n", key_len);
 732                        res = -EIO;
 733                        goto end_listxattr;
 734                }
 735
 736                hfs_bnode_read(fd.bnode, &attr_key,
 737                                fd.keyoffset, key_len + sizeof(key_len));
 738
 739                if (be32_to_cpu(attr_key.cnid) != inode->i_ino)
 740                        goto end_listxattr;
 741
 742                xattr_name_len = NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN;
 743                if (hfsplus_uni2asc(inode->i_sb,
 744                        (const struct hfsplus_unistr *)&fd.key->attr.key_name,
 745                                        strbuf, &xattr_name_len)) {
 746                        pr_err("unicode conversion failed\n");
 747                        res = -EIO;
 748                        goto end_listxattr;
 749                }
 750
 751                if (!buffer || !size) {
 752                        if (can_list(strbuf))
 753                                res += name_len(strbuf, xattr_name_len);
 754                } else if (can_list(strbuf)) {
 755                        if (size < (res + name_len(strbuf, xattr_name_len))) {
 756                                res = -ERANGE;
 757                                goto end_listxattr;
 758                        } else
 759                                res += copy_name(buffer + res,
 760                                                strbuf, xattr_name_len);
 761                }
 762
 763                if (hfs_brec_goto(&fd, 1))
 764                        goto end_listxattr;
 765        }
 766
 767end_listxattr:
 768        kfree(strbuf);
 769out:
 770        hfs_find_exit(&fd);
 771        return res;
 772}
 773
 774static int hfsplus_removexattr(struct inode *inode, const char *name)
 775{
 776        int err = 0;
 777        struct hfs_find_data cat_fd;
 778        u16 flags;
 779        u16 cat_entry_type;
 780        int is_xattr_acl_deleted = 0;
 781        int is_all_xattrs_deleted = 0;
 782
 783        if (!HFSPLUS_SB(inode->i_sb)->attr_tree)
 784                return -EOPNOTSUPP;
 785
 786        if (!strcmp_xattr_finder_info(name))
 787                return -EOPNOTSUPP;
 788
 789        err = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &cat_fd);
 790        if (err) {
 791                pr_err("can't init xattr find struct\n");
 792                return err;
 793        }
 794
 795        err = hfsplus_find_cat(inode->i_sb, inode->i_ino, &cat_fd);
 796        if (err) {
 797                pr_err("catalog searching failed\n");
 798                goto end_removexattr;
 799        }
 800
 801        err = hfsplus_delete_attr(inode, name);
 802        if (err)
 803                goto end_removexattr;
 804
 805        is_xattr_acl_deleted = !strcmp_xattr_acl(name);
 806        is_all_xattrs_deleted = !hfsplus_attr_exists(inode, NULL);
 807
 808        if (!is_xattr_acl_deleted && !is_all_xattrs_deleted)
 809                goto end_removexattr;
 810
 811        cat_entry_type = hfs_bnode_read_u16(cat_fd.bnode, cat_fd.entryoffset);
 812
 813        if (cat_entry_type == HFSPLUS_FOLDER) {
 814                flags = hfs_bnode_read_u16(cat_fd.bnode, cat_fd.entryoffset +
 815                                offsetof(struct hfsplus_cat_folder, flags));
 816                if (is_xattr_acl_deleted)
 817                        flags &= ~HFSPLUS_ACL_EXISTS;
 818                if (is_all_xattrs_deleted)
 819                        flags &= ~HFSPLUS_XATTR_EXISTS;
 820                hfs_bnode_write_u16(cat_fd.bnode, cat_fd.entryoffset +
 821                                offsetof(struct hfsplus_cat_folder, flags),
 822                                flags);
 823                hfsplus_mark_inode_dirty(inode, HFSPLUS_I_CAT_DIRTY);
 824        } else if (cat_entry_type == HFSPLUS_FILE) {
 825                flags = hfs_bnode_read_u16(cat_fd.bnode, cat_fd.entryoffset +
 826                                offsetof(struct hfsplus_cat_file, flags));
 827                if (is_xattr_acl_deleted)
 828                        flags &= ~HFSPLUS_ACL_EXISTS;
 829                if (is_all_xattrs_deleted)
 830                        flags &= ~HFSPLUS_XATTR_EXISTS;
 831                hfs_bnode_write_u16(cat_fd.bnode, cat_fd.entryoffset +
 832                                offsetof(struct hfsplus_cat_file, flags),
 833                                flags);
 834                hfsplus_mark_inode_dirty(inode, HFSPLUS_I_CAT_DIRTY);
 835        } else {
 836                pr_err("invalid catalog entry type\n");
 837                err = -EIO;
 838                goto end_removexattr;
 839        }
 840
 841end_removexattr:
 842        hfs_find_exit(&cat_fd);
 843        return err;
 844}
 845
 846static int hfsplus_osx_getxattr(const struct xattr_handler *handler,
 847                                struct dentry *dentry, const char *name,
 848                                void *buffer, size_t size)
 849{
 850        /*
 851         * Don't allow retrieving properly prefixed attributes
 852         * by prepending them with "osx."
 853         */
 854        if (is_known_namespace(name))
 855                return -EOPNOTSUPP;
 856
 857        /*
 858         * osx is the namespace we use to indicate an unprefixed
 859         * attribute on the filesystem (like the ones that OS X
 860         * creates), so we pass the name through unmodified (after
 861         * ensuring it doesn't conflict with another namespace).
 862         */
 863        return __hfsplus_getxattr(d_inode(dentry), name, buffer, size);
 864}
 865
 866static int hfsplus_osx_setxattr(const struct xattr_handler *handler,
 867                                struct dentry *dentry, const char *name,
 868                                const void *buffer, size_t size, int flags)
 869{
 870        /*
 871         * Don't allow setting properly prefixed attributes
 872         * by prepending them with "osx."
 873         */
 874        if (is_known_namespace(name))
 875                return -EOPNOTSUPP;
 876
 877        /*
 878         * osx is the namespace we use to indicate an unprefixed
 879         * attribute on the filesystem (like the ones that OS X
 880         * creates), so we pass the name through unmodified (after
 881         * ensuring it doesn't conflict with another namespace).
 882         */
 883        return __hfsplus_setxattr(d_inode(dentry), name, buffer, size, flags);
 884}
 885
 886const struct xattr_handler hfsplus_xattr_osx_handler = {
 887        .prefix = XATTR_MAC_OSX_PREFIX,
 888        .get    = hfsplus_osx_getxattr,
 889        .set    = hfsplus_osx_setxattr,
 890};
 891