diff options
Diffstat (limited to 'fs/f2fs/acl.c')
| -rw-r--r-- | fs/f2fs/acl.c | 280 | 
1 files changed, 280 insertions, 0 deletions
diff --git a/fs/f2fs/acl.c b/fs/f2fs/acl.c new file mode 100644 index 00000000000..dbe2141d10a --- /dev/null +++ b/fs/f2fs/acl.c @@ -0,0 +1,280 @@ +/* + * fs/f2fs/acl.c + * + * Copyright (c) 2012 Samsung Electronics Co., Ltd. + *             http://www.samsung.com/ + * + * Portions of this code from linux/fs/ext2/acl.c + * + * Copyright (C) 2001-2003 Andreas Gruenbacher, <agruen@suse.de> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include <linux/f2fs_fs.h> +#include "f2fs.h" +#include "xattr.h" +#include "acl.h" + +static inline size_t f2fs_acl_size(int count) +{ +	if (count <= 4) { +		return sizeof(struct f2fs_acl_header) + +			count * sizeof(struct f2fs_acl_entry_short); +	} else { +		return sizeof(struct f2fs_acl_header) + +			4 * sizeof(struct f2fs_acl_entry_short) + +			(count - 4) * sizeof(struct f2fs_acl_entry); +	} +} + +static inline int f2fs_acl_count(size_t size) +{ +	ssize_t s; +	size -= sizeof(struct f2fs_acl_header); +	s = size - 4 * sizeof(struct f2fs_acl_entry_short); +	if (s < 0) { +		if (size % sizeof(struct f2fs_acl_entry_short)) +			return -1; +		return size / sizeof(struct f2fs_acl_entry_short); +	} else { +		if (s % sizeof(struct f2fs_acl_entry)) +			return -1; +		return s / sizeof(struct f2fs_acl_entry) + 4; +	} +} + +static struct posix_acl *f2fs_acl_from_disk(const char *value, size_t size) +{ +	int i, count; +	struct posix_acl *acl; +	struct f2fs_acl_header *hdr = (struct f2fs_acl_header *)value; +	struct f2fs_acl_entry *entry = (struct f2fs_acl_entry *)(hdr + 1); +	const char *end = value + size; + +	if (hdr->a_version != cpu_to_le32(F2FS_ACL_VERSION)) +		return ERR_PTR(-EINVAL); + +	count = f2fs_acl_count(size); +	if (count < 0) +		return ERR_PTR(-EINVAL); +	if (count == 0) +		return NULL; + +	acl = posix_acl_alloc(count, GFP_KERNEL); +	if (!acl) +		return ERR_PTR(-ENOMEM); + +	for (i = 0; i < count; i++) { + +		if ((char *)entry > end) +			goto fail; + +		acl->a_entries[i].e_tag  = le16_to_cpu(entry->e_tag); +		acl->a_entries[i].e_perm = le16_to_cpu(entry->e_perm); + +		switch (acl->a_entries[i].e_tag) { +		case ACL_USER_OBJ: +		case ACL_GROUP_OBJ: +		case ACL_MASK: +		case ACL_OTHER: +			entry = (struct f2fs_acl_entry *)((char *)entry + +					sizeof(struct f2fs_acl_entry_short)); +			break; + +		case ACL_USER: +			acl->a_entries[i].e_uid = +				make_kuid(&init_user_ns, +						le32_to_cpu(entry->e_id)); +			entry = (struct f2fs_acl_entry *)((char *)entry + +					sizeof(struct f2fs_acl_entry)); +			break; +		case ACL_GROUP: +			acl->a_entries[i].e_gid = +				make_kgid(&init_user_ns, +						le32_to_cpu(entry->e_id)); +			entry = (struct f2fs_acl_entry *)((char *)entry + +					sizeof(struct f2fs_acl_entry)); +			break; +		default: +			goto fail; +		} +	} +	if ((char *)entry != end) +		goto fail; +	return acl; +fail: +	posix_acl_release(acl); +	return ERR_PTR(-EINVAL); +} + +static void *f2fs_acl_to_disk(const struct posix_acl *acl, size_t *size) +{ +	struct f2fs_acl_header *f2fs_acl; +	struct f2fs_acl_entry *entry; +	int i; + +	f2fs_acl = kmalloc(sizeof(struct f2fs_acl_header) + acl->a_count * +			sizeof(struct f2fs_acl_entry), GFP_KERNEL); +	if (!f2fs_acl) +		return ERR_PTR(-ENOMEM); + +	f2fs_acl->a_version = cpu_to_le32(F2FS_ACL_VERSION); +	entry = (struct f2fs_acl_entry *)(f2fs_acl + 1); + +	for (i = 0; i < acl->a_count; i++) { + +		entry->e_tag  = cpu_to_le16(acl->a_entries[i].e_tag); +		entry->e_perm = cpu_to_le16(acl->a_entries[i].e_perm); + +		switch (acl->a_entries[i].e_tag) { +		case ACL_USER: +			entry->e_id = cpu_to_le32( +					from_kuid(&init_user_ns, +						acl->a_entries[i].e_uid)); +			entry = (struct f2fs_acl_entry *)((char *)entry + +					sizeof(struct f2fs_acl_entry)); +			break; +		case ACL_GROUP: +			entry->e_id = cpu_to_le32( +					from_kgid(&init_user_ns, +						acl->a_entries[i].e_gid)); +			entry = (struct f2fs_acl_entry *)((char *)entry + +					sizeof(struct f2fs_acl_entry)); +			break; +		case ACL_USER_OBJ: +		case ACL_GROUP_OBJ: +		case ACL_MASK: +		case ACL_OTHER: +			entry = (struct f2fs_acl_entry *)((char *)entry + +					sizeof(struct f2fs_acl_entry_short)); +			break; +		default: +			goto fail; +		} +	} +	*size = f2fs_acl_size(acl->a_count); +	return (void *)f2fs_acl; + +fail: +	kfree(f2fs_acl); +	return ERR_PTR(-EINVAL); +} + +struct posix_acl *f2fs_get_acl(struct inode *inode, int type) +{ +	int name_index = F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT; +	void *value = NULL; +	struct posix_acl *acl; +	int retval; + +	if (type == ACL_TYPE_ACCESS) +		name_index = F2FS_XATTR_INDEX_POSIX_ACL_ACCESS; + +	retval = f2fs_getxattr(inode, name_index, "", NULL, 0); +	if (retval > 0) { +		value = kmalloc(retval, GFP_F2FS_ZERO); +		if (!value) +			return ERR_PTR(-ENOMEM); +		retval = f2fs_getxattr(inode, name_index, "", value, retval); +	} + +	if (retval > 0) +		acl = f2fs_acl_from_disk(value, retval); +	else if (retval == -ENODATA) +		acl = NULL; +	else +		acl = ERR_PTR(retval); +	kfree(value); + +	if (!IS_ERR(acl)) +		set_cached_acl(inode, type, acl); + +	return acl; +} + +static int __f2fs_set_acl(struct inode *inode, int type, +			struct posix_acl *acl, struct page *ipage) +{ +	struct f2fs_inode_info *fi = F2FS_I(inode); +	int name_index; +	void *value = NULL; +	size_t size = 0; +	int error; + +	if (acl) { +		error = posix_acl_valid(acl); +		if (error < 0) +			return error; +	} + +	switch (type) { +	case ACL_TYPE_ACCESS: +		name_index = F2FS_XATTR_INDEX_POSIX_ACL_ACCESS; +		if (acl) { +			error = posix_acl_equiv_mode(acl, &inode->i_mode); +			if (error < 0) +				return error; +			set_acl_inode(fi, inode->i_mode); +			if (error == 0) +				acl = NULL; +		} +		break; + +	case ACL_TYPE_DEFAULT: +		name_index = F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT; +		if (!S_ISDIR(inode->i_mode)) +			return acl ? -EACCES : 0; +		break; + +	default: +		return -EINVAL; +	} + +	if (acl) { +		value = f2fs_acl_to_disk(acl, &size); +		if (IS_ERR(value)) { +			cond_clear_inode_flag(fi, FI_ACL_MODE); +			return (int)PTR_ERR(value); +		} +	} + +	error = f2fs_setxattr(inode, name_index, "", value, size, ipage, 0); + +	kfree(value); +	if (!error) +		set_cached_acl(inode, type, acl); + +	cond_clear_inode_flag(fi, FI_ACL_MODE); +	return error; +} + +int f2fs_set_acl(struct inode *inode, struct posix_acl *acl, int type) +{ +	return __f2fs_set_acl(inode, type, acl, NULL); +} + +int f2fs_init_acl(struct inode *inode, struct inode *dir, struct page *ipage) +{ +	struct posix_acl *default_acl, *acl; +	int error = 0; + +	error = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl); +	if (error) +		return error; + +	if (default_acl) { +		error = __f2fs_set_acl(inode, ACL_TYPE_DEFAULT, default_acl, +				       ipage); +		posix_acl_release(default_acl); +	} +	if (acl) { +		if (error) +			error = __f2fs_set_acl(inode, ACL_TYPE_ACCESS, acl, +					       ipage); +		posix_acl_release(acl); +	} + +	return error; +}  | 
