| #include <linux/capability.h> |
| #include <linux/fs.h> |
| #include <linux/posix_acl.h> |
| #include "reiserfs.h" |
| #include <linux/errno.h> |
| #include <linux/pagemap.h> |
| #include <linux/xattr.h> |
| #include <linux/slab.h> |
| #include <linux/posix_acl_xattr.h> |
| #include "xattr.h" |
| #include "acl.h" |
| #include <linux/uaccess.h> |
| |
| static int __reiserfs_set_acl(struct reiserfs_transaction_handle *th, |
| struct inode *inode, int type, |
| struct posix_acl *acl); |
| |
| |
| int |
| reiserfs_set_acl(struct inode *inode, struct posix_acl *acl, int type) |
| { |
| int error, error2; |
| struct reiserfs_transaction_handle th; |
| size_t jcreate_blocks; |
| int size = acl ? posix_acl_xattr_size(acl->a_count) : 0; |
| |
| |
| /* |
| * Pessimism: We can't assume that anything from the xattr root up |
| * has been created. |
| */ |
| |
| jcreate_blocks = reiserfs_xattr_jcreate_nblocks(inode) + |
| reiserfs_xattr_nblocks(inode, size) * 2; |
| |
| reiserfs_write_lock(inode->i_sb); |
| error = journal_begin(&th, inode->i_sb, jcreate_blocks); |
| reiserfs_write_unlock(inode->i_sb); |
| if (error == 0) { |
| error = __reiserfs_set_acl(&th, inode, type, acl); |
| reiserfs_write_lock(inode->i_sb); |
| error2 = journal_end(&th); |
| reiserfs_write_unlock(inode->i_sb); |
| if (error2) |
| error = error2; |
| } |
| |
| return error; |
| } |
| |
| /* |
| * Convert from filesystem to in-memory representation. |
| */ |
| static struct posix_acl *reiserfs_posix_acl_from_disk(const void *value, size_t size) |
| { |
| const char *end = (char *)value + size; |
| int n, count; |
| struct posix_acl *acl; |
| |
| if (!value) |
| return NULL; |
| if (size < sizeof(reiserfs_acl_header)) |
| return ERR_PTR(-EINVAL); |
| if (((reiserfs_acl_header *) value)->a_version != |
| cpu_to_le32(REISERFS_ACL_VERSION)) |
| return ERR_PTR(-EINVAL); |
| value = (char *)value + sizeof(reiserfs_acl_header); |
| count = reiserfs_acl_count(size); |
| if (count < 0) |
| return ERR_PTR(-EINVAL); |
| if (count == 0) |
| return NULL; |
| acl = posix_acl_alloc(count, GFP_NOFS); |
| if (!acl) |
| return ERR_PTR(-ENOMEM); |
| for (n = 0; n < count; n++) { |
| reiserfs_acl_entry *entry = (reiserfs_acl_entry *) value; |
| if ((char *)value + sizeof(reiserfs_acl_entry_short) > end) |
| goto fail; |
| acl->a_entries[n].e_tag = le16_to_cpu(entry->e_tag); |
| acl->a_entries[n].e_perm = le16_to_cpu(entry->e_perm); |
| switch (acl->a_entries[n].e_tag) { |
| case ACL_USER_OBJ: |
| case ACL_GROUP_OBJ: |
| case ACL_MASK: |
| case ACL_OTHER: |
| value = (char *)value + |
| sizeof(reiserfs_acl_entry_short); |
| break; |
| |
| case ACL_USER: |
| value = (char *)value + sizeof(reiserfs_acl_entry); |
| if ((char *)value > end) |
| goto fail; |
| acl->a_entries[n].e_uid = |
| make_kuid(&init_user_ns, |
| le32_to_cpu(entry->e_id)); |
| break; |
| case ACL_GROUP: |
| value = (char *)value + sizeof(reiserfs_acl_entry); |
| if ((char *)value > end) |
| goto fail; |
| acl->a_entries[n].e_gid = |
| make_kgid(&init_user_ns, |
| le32_to_cpu(entry->e_id)); |
| break; |
| |
| default: |
| goto fail; |
| } |
| } |
| if (value != end) |
| goto fail; |
| return acl; |
| |
| fail: |
| posix_acl_release(acl); |
| return ERR_PTR(-EINVAL); |
| } |
| |
| /* |
| * Convert from in-memory to filesystem representation. |
| */ |
| static void *reiserfs_posix_acl_to_disk(const struct posix_acl *acl, size_t * size) |
| { |
| reiserfs_acl_header *ext_acl; |
| char *e; |
| int n; |
| |
| *size = reiserfs_acl_size(acl->a_count); |
| ext_acl = kmalloc(sizeof(reiserfs_acl_header) + |
| acl->a_count * |
| sizeof(reiserfs_acl_entry), |
| GFP_NOFS); |
| if (!ext_acl) |
| return ERR_PTR(-ENOMEM); |
| ext_acl->a_version = cpu_to_le32(REISERFS_ACL_VERSION); |
| e = (char *)ext_acl + sizeof(reiserfs_acl_header); |
| for (n = 0; n < acl->a_count; n++) { |
| const struct posix_acl_entry *acl_e = &acl->a_entries[n]; |
| reiserfs_acl_entry *entry = (reiserfs_acl_entry *) e; |
| entry->e_tag = cpu_to_le16(acl->a_entries[n].e_tag); |
| entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm); |
| switch (acl->a_entries[n].e_tag) { |
| case ACL_USER: |
| entry->e_id = cpu_to_le32( |
| from_kuid(&init_user_ns, acl_e->e_uid)); |
| e += sizeof(reiserfs_acl_entry); |
| break; |
| case ACL_GROUP: |
| entry->e_id = cpu_to_le32( |
| from_kgid(&init_user_ns, acl_e->e_gid)); |
| e += sizeof(reiserfs_acl_entry); |
| break; |
| |
| case ACL_USER_OBJ: |
| case ACL_GROUP_OBJ: |
| case ACL_MASK: |
| case ACL_OTHER: |
| e += sizeof(reiserfs_acl_entry_short); |
| break; |
| |
| default: |
| goto fail; |
| } |
| } |
| return (char *)ext_acl; |
| |
| fail: |
| kfree(ext_acl); |
| return ERR_PTR(-EINVAL); |
| } |
| |
| /* |
| * Inode operation get_posix_acl(). |
| * |
| * inode->i_mutex: down |
| * BKL held [before 2.5.x] |
| */ |
| struct posix_acl *reiserfs_get_acl(struct inode *inode, int type) |
| { |
| char *name, *value; |
| struct posix_acl *acl; |
| int size; |
| int retval; |
| |
| switch (type) { |
| case ACL_TYPE_ACCESS: |
| name = XATTR_NAME_POSIX_ACL_ACCESS; |
| break; |
| case ACL_TYPE_DEFAULT: |
| name = XATTR_NAME_POSIX_ACL_DEFAULT; |
| break; |
| default: |
| BUG(); |
| } |
| |
| size = reiserfs_xattr_get(inode, name, NULL, 0); |
| if (size < 0) { |
| if (size == -ENODATA || size == -ENOSYS) { |
| set_cached_acl(inode, type, NULL); |
| return NULL; |
| } |
| return ERR_PTR(size); |
| } |
| |
| value = kmalloc(size, GFP_NOFS); |
| if (!value) |
| return ERR_PTR(-ENOMEM); |
| |
| retval = reiserfs_xattr_get(inode, name, value, size); |
| if (retval == -ENODATA || retval == -ENOSYS) { |
| /* |
| * This shouldn't actually happen as it should have |
| * been caught above.. but just in case |
| */ |
| acl = NULL; |
| } else if (retval < 0) { |
| acl = ERR_PTR(retval); |
| } else { |
| acl = reiserfs_posix_acl_from_disk(value, retval); |
| } |
| if (!IS_ERR(acl)) |
| set_cached_acl(inode, type, acl); |
| |
| kfree(value); |
| return acl; |
| } |
| |
| /* |
| * Inode operation set_posix_acl(). |
| * |
| * inode->i_mutex: down |
| * BKL held [before 2.5.x] |
| */ |
| static int |
| __reiserfs_set_acl(struct reiserfs_transaction_handle *th, struct inode *inode, |
| int type, struct posix_acl *acl) |
| { |
| char *name; |
| void *value = NULL; |
| size_t size = 0; |
| int error; |
| |
| switch (type) { |
| case ACL_TYPE_ACCESS: |
| name = XATTR_NAME_POSIX_ACL_ACCESS; |
| if (acl) { |
| error = posix_acl_equiv_mode(acl, &inode->i_mode); |
| if (error < 0) |
| return error; |
| else { |
| if (error == 0) |
| acl = NULL; |
| } |
| } |
| break; |
| case ACL_TYPE_DEFAULT: |
| name = XATTR_NAME_POSIX_ACL_DEFAULT; |
| if (!S_ISDIR(inode->i_mode)) |
| return acl ? -EACCES : 0; |
| break; |
| default: |
| return -EINVAL; |
| } |
| |
| if (acl) { |
| value = reiserfs_posix_acl_to_disk(acl, &size); |
| if (IS_ERR(value)) |
| return (int)PTR_ERR(value); |
| } |
| |
| error = reiserfs_xattr_set_handle(th, inode, name, value, size, 0); |
| |
| /* |
| * Ensure that the inode gets dirtied if we're only using |
| * the mode bits and an old ACL didn't exist. We don't need |
| * to check if the inode is hashed here since we won't get |
| * called by reiserfs_inherit_default_acl(). |
| */ |
| if (error == -ENODATA) { |
| error = 0; |
| if (type == ACL_TYPE_ACCESS) { |
| inode->i_ctime = CURRENT_TIME_SEC; |
| mark_inode_dirty(inode); |
| } |
| } |
| |
| kfree(value); |
| |
| if (!error) |
| set_cached_acl(inode, type, acl); |
| |
| return error; |
| } |
| |
| /* |
| * dir->i_mutex: locked, |
| * inode is new and not released into the wild yet |
| */ |
| int |
| reiserfs_inherit_default_acl(struct reiserfs_transaction_handle *th, |
| struct inode *dir, struct dentry *dentry, |
| struct inode *inode) |
| { |
| struct posix_acl *default_acl, *acl; |
| int err = 0; |
| |
| /* ACLs only get applied to files and directories */ |
| if (S_ISLNK(inode->i_mode)) |
| return 0; |
| |
| /* |
| * ACLs can only be used on "new" objects, so if it's an old object |
| * there is nothing to inherit from |
| */ |
| if (get_inode_sd_version(dir) == STAT_DATA_V1) |
| goto apply_umask; |
| |
| /* |
| * Don't apply ACLs to objects in the .reiserfs_priv tree.. This |
| * would be useless since permissions are ignored, and a pain because |
| * it introduces locking cycles |
| */ |
| if (IS_PRIVATE(dir)) { |
| inode->i_flags |= S_PRIVATE; |
| goto apply_umask; |
| } |
| |
| err = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl); |
| if (err) |
| return err; |
| |
| if (default_acl) { |
| err = __reiserfs_set_acl(th, inode, ACL_TYPE_DEFAULT, |
| default_acl); |
| posix_acl_release(default_acl); |
| } |
| if (acl) { |
| if (!err) |
| err = __reiserfs_set_acl(th, inode, ACL_TYPE_ACCESS, |
| acl); |
| posix_acl_release(acl); |
| } |
| |
| return err; |
| |
| apply_umask: |
| /* no ACL, apply umask */ |
| inode->i_mode &= ~current_umask(); |
| return err; |
| } |
| |
| /* This is used to cache the default acl before a new object is created. |
| * The biggest reason for this is to get an idea of how many blocks will |
| * actually be required for the create operation if we must inherit an ACL. |
| * An ACL write can add up to 3 object creations and an additional file write |
| * so we'd prefer not to reserve that many blocks in the journal if we can. |
| * It also has the advantage of not loading the ACL with a transaction open, |
| * this may seem silly, but if the owner of the directory is doing the |
| * creation, the ACL may not be loaded since the permissions wouldn't require |
| * it. |
| * We return the number of blocks required for the transaction. |
| */ |
| int reiserfs_cache_default_acl(struct inode *inode) |
| { |
| struct posix_acl *acl; |
| int nblocks = 0; |
| |
| if (IS_PRIVATE(inode)) |
| return 0; |
| |
| acl = get_acl(inode, ACL_TYPE_DEFAULT); |
| |
| if (acl && !IS_ERR(acl)) { |
| int size = reiserfs_acl_size(acl->a_count); |
| |
| /* Other xattrs can be created during inode creation. We don't |
| * want to claim too many blocks, so we check to see if we |
| * we need to create the tree to the xattrs, and then we |
| * just want two files. */ |
| nblocks = reiserfs_xattr_jcreate_nblocks(inode); |
| nblocks += JOURNAL_BLOCKS_PER_OBJECT(inode->i_sb); |
| |
| REISERFS_I(inode)->i_flags |= i_has_xattr_dir; |
| |
| /* We need to account for writes + bitmaps for two files */ |
| nblocks += reiserfs_xattr_nblocks(inode, size) * 4; |
| posix_acl_release(acl); |
| } |
| |
| return nblocks; |
| } |
| |
| /* |
| * Called under i_mutex |
| */ |
| int reiserfs_acl_chmod(struct inode *inode) |
| { |
| if (IS_PRIVATE(inode)) |
| return 0; |
| if (get_inode_sd_version(inode) == STAT_DATA_V1 || |
| !reiserfs_posixacl(inode->i_sb)) |
| return 0; |
| |
| return posix_acl_chmod(inode, inode->i_mode); |
| } |