// SPDX-License-Identifier: GPL-2.0 /* * linux/fs/hfsplus/attributes.c * * Vyacheslav Dubeyko <slava@dubeyko.com> * * Handling of records in attributes tree */ #include "hfsplus_fs.h" #include "hfsplus_raw.h" static struct kmem_cache *hfsplus_attr_tree_cachep; int __init hfsplus_create_attr_tree_cache(void) { if (hfsplus_attr_tree_cachep) return -EEXIST; hfsplus_attr_tree_cachep = kmem_cache_create("hfsplus_attr_cache", sizeof(hfsplus_attr_entry), 0, SLAB_HWCACHE_ALIGN, NULL); if (!hfsplus_attr_tree_cachep) return -ENOMEM; return 0; } void hfsplus_destroy_attr_tree_cache(void) { kmem_cache_destroy(hfsplus_attr_tree_cachep); } int hfsplus_attr_bin_cmp_key(const hfsplus_btree_key *k1, const hfsplus_btree_key *k2) { __be32 k1_cnid, k2_cnid; k1_cnid = k1->attr.cnid; k2_cnid = k2->attr.cnid; if (k1_cnid != k2_cnid) return be32_to_cpu(k1_cnid) < be32_to_cpu(k2_cnid) ? -1 : 1; return hfsplus_strcmp( (const struct hfsplus_unistr *)&k1->attr.key_name, (const struct hfsplus_unistr *)&k2->attr.key_name); } int hfsplus_attr_build_key(struct super_block *sb, hfsplus_btree_key *key, u32 cnid, const char *name) { int len; memset(key, 0, sizeof(struct hfsplus_attr_key)); key->attr.cnid = cpu_to_be32(cnid); if (name) { int res = hfsplus_asc2uni(sb, (struct hfsplus_unistr *)&key->attr.key_name, HFSPLUS_ATTR_MAX_STRLEN, name, strlen(name)); if (res) return res; len = be16_to_cpu(key->attr.key_name.length); } else { key->attr.key_name.length = 0; len = 0; } /* The length of the key, as stored in key_len field, does not include * the size of the key_len field itself. * So, offsetof(hfsplus_attr_key, key_name) is a trick because * it takes into consideration key_len field (__be16) of * hfsplus_attr_key structure instead of length field (__be16) of * hfsplus_attr_unistr structure. */ key->key_len = cpu_to_be16(offsetof(struct hfsplus_attr_key, key_name) + 2 * len); return 0; } hfsplus_attr_entry *hfsplus_alloc_attr_entry(void) { return kmem_cache_alloc(hfsplus_attr_tree_cachep, GFP_KERNEL); } void hfsplus_destroy_attr_entry(hfsplus_attr_entry *entry) { if (entry) kmem_cache_free(hfsplus_attr_tree_cachep, entry); } #define HFSPLUS_INVALID_ATTR_RECORD -1 static int hfsplus_attr_build_record(hfsplus_attr_entry *entry, int record_type, u32 cnid, const void *value, size_t size) { if (record_type == HFSPLUS_ATTR_FORK_DATA) { /* * Mac OS X supports only inline data attributes. * Do nothing */ memset(entry, 0, sizeof(*entry)); return sizeof(struct hfsplus_attr_fork_data); } else if (record_type == HFSPLUS_ATTR_EXTENTS) { /* * Mac OS X supports only inline data attributes. * Do nothing. */ memset(entry, 0, sizeof(*entry)); return sizeof(struct hfsplus_attr_extents); } else if (record_type == HFSPLUS_ATTR_INLINE_DATA) { u16 len; memset(entry, 0, sizeof(struct hfsplus_attr_inline_data)); entry->inline_data.record_type = cpu_to_be32(record_type); if (size <= HFSPLUS_MAX_INLINE_DATA_SIZE) len = size; else return HFSPLUS_INVALID_ATTR_RECORD; entry->inline_data.length = cpu_to_be16(len); memcpy(entry->inline_data.raw_bytes, value, len); /* * Align len on two-byte boundary. * It needs to add pad byte if we have odd len. */ len = round_up(len, 2); return offsetof(struct hfsplus_attr_inline_data, raw_bytes) + len; } else /* invalid input */ memset(entry, 0, sizeof(*entry)); return HFSPLUS_INVALID_ATTR_RECORD; } int hfsplus_find_attr(struct super_block *sb, u32 cnid, const char *name, struct hfs_find_data *fd) { int err = 0; hfs_dbg(ATTR_MOD, "find_attr: %s,%d\n", name ? name : NULL, cnid); if (!HFSPLUS_SB(sb)->attr_tree) { pr_err("attributes file doesn't exist\n"); return -EINVAL; } if (name) { err = hfsplus_attr_build_key(sb, fd->search_key, cnid, name); if (err) goto failed_find_attr; err = hfs_brec_find(fd, hfs_find_rec_by_key); if (err) goto failed_find_attr; } else { err = hfsplus_attr_build_key(sb, fd->search_key, cnid, NULL); if (err) goto failed_find_attr; err = hfs_brec_find(fd, hfs_find_1st_rec_by_cnid); if (err) goto failed_find_attr; } failed_find_attr: return err; } int hfsplus_attr_exists(struct inode *inode, const char *name) { int err = 0; struct super_block *sb = inode->i_sb; struct hfs_find_data fd; if (!HFSPLUS_SB(sb)->attr_tree) return 0; err = hfs_find_init(HFSPLUS_SB(sb)->attr_tree, &fd); if (err) return 0; err = hfsplus_find_attr(sb, inode->i_ino, name, &fd); if (err) goto attr_not_found; hfs_find_exit(&fd); return 1; attr_not_found: hfs_find_exit(&fd); return 0; } int hfsplus_create_attr(struct inode *inode, const char *name, const void *value, size_t size) { struct super_block *sb = inode->i_sb; struct hfs_find_data fd; hfsplus_attr_entry *entry_ptr; int entry_size; int err; hfs_dbg(ATTR_MOD, "create_attr: %s,%ld\n", name ? name : NULL, inode->i_ino); if (!HFSPLUS_SB(sb)->attr_tree) { pr_err("attributes file doesn't exist\n"); return -EINVAL; } entry_ptr = hfsplus_alloc_attr_entry(); if (!entry_ptr) return -ENOMEM; err = hfs_find_init(HFSPLUS_SB(sb)->attr_tree, &fd); if (err) goto failed_init_create_attr; if (name) { err = hfsplus_attr_build_key(sb, fd.search_key, inode->i_ino, name); if (err) goto failed_create_attr; } else { err = -EINVAL; goto failed_create_attr; } /* Mac OS X supports only inline data attributes. */ entry_size = hfsplus_attr_build_record(entry_ptr, HFSPLUS_ATTR_INLINE_DATA, inode->i_ino, value, size); if (entry_size == HFSPLUS_INVALID_ATTR_RECORD) { err = -EINVAL; goto failed_create_attr; } err = hfs_brec_find(&fd, hfs_find_rec_by_key); if (err != -ENOENT) { if (!err) err = -EEXIST; goto failed_create_attr; } err = hfs_brec_insert(&fd, entry_ptr, entry_size); if (err) goto failed_create_attr; hfsplus_mark_inode_dirty(inode, HFSPLUS_I_ATTR_DIRTY); failed_create_attr: hfs_find_exit(&fd); failed_init_create_attr: hfsplus_destroy_attr_entry(entry_ptr); return err; } static int __hfsplus_delete_attr(struct inode *inode, u32 cnid, struct hfs_find_data *fd) { int err = 0; __be32 found_cnid, record_type; hfs_bnode_read(fd->bnode, &found_cnid, fd->keyoffset + offsetof(struct hfsplus_attr_key, cnid), sizeof(__be32)); if (cnid != be32_to_cpu(found_cnid)) return -ENOENT; hfs_bnode_read(fd->bnode, &record_type, fd->entryoffset, sizeof(record_type)); switch (be32_to_cpu(record_type)) { case HFSPLUS_ATTR_INLINE_DATA: /* All is OK. Do nothing. */ break; case HFSPLUS_ATTR_FORK_DATA: case HFSPLUS_ATTR_EXTENTS: pr_err("only inline data xattr are supported\n"); return -EOPNOTSUPP; default: pr_err("invalid extended attribute record\n"); return -ENOENT; } err = hfs_brec_remove(fd); if (err) return err; hfsplus_mark_inode_dirty(inode, HFSPLUS_I_ATTR_DIRTY); return err; } int hfsplus_delete_attr(struct inode *inode, const char *name) { int err = 0; struct super_block *sb = inode->i_sb; struct hfs_find_data fd; hfs_dbg(ATTR_MOD, "delete_attr: %s,%ld\n", name ? name : NULL, inode->i_ino); if (!HFSPLUS_SB(sb)->attr_tree) { pr_err("attributes file doesn't exist\n"); return -EINVAL; } err = hfs_find_init(HFSPLUS_SB(sb)->attr_tree, &fd); if (err) return err; if (name) { err = hfsplus_attr_build_key(sb, fd.search_key, inode->i_ino, name); if (err) goto out; } else { pr_err("invalid extended attribute name\n"); err = -EINVAL; goto out; } err = hfs_brec_find(&fd, hfs_find_rec_by_key); if (err) goto out; err = __hfsplus_delete_attr(inode, inode->i_ino, &fd); if (err) goto out; out: hfs_find_exit(&fd); return err; } int hfsplus_delete_all_attrs(struct inode *dir, u32 cnid) { int err = 0; struct hfs_find_data fd; hfs_dbg(ATTR_MOD, "delete_all_attrs: %d\n", cnid); if (!HFSPLUS_SB(dir->i_sb)->attr_tree) { pr_err("attributes file doesn't exist\n"); return -EINVAL; } err = hfs_find_init(HFSPLUS_SB(dir->i_sb)->attr_tree, &fd); if (err) return err; for (;;) { err = hfsplus_find_attr(dir->i_sb, cnid, NULL, &fd); if (err) { if (err != -ENOENT) pr_err("xattr search failed\n"); goto end_delete_all; } err = __hfsplus_delete_attr(dir, cnid, &fd); if (err) goto end_delete_all; } end_delete_all: hfs_find_exit(&fd); return err; }