diff options
Diffstat (limited to 'fs/f2fs/acl.c')
| -rw-r--r-- | fs/f2fs/acl.c | 412 |
1 files changed, 412 insertions, 0 deletions
diff --git a/fs/f2fs/acl.c b/fs/f2fs/acl.c new file mode 100644 index 000000000000..137af4255da6 --- /dev/null +++ b/fs/f2fs/acl.c @@ -0,0 +1,412 @@ +/* + * 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" + +#define get_inode_mode(i) ((is_inode_flag_set(F2FS_I(i), FI_ACL_MODE)) ? \ + (F2FS_I(i)->i_acl_mode) : ((i)->i_mode)) + +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) +{ + struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb); + int name_index = F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT; + void *value = NULL; + struct posix_acl *acl; + int retval; + + if (!test_opt(sbi, POSIX_ACL)) + return NULL; + + acl = get_cached_acl(inode, type); + if (acl != ACL_NOT_CACHED) + return acl; + + 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_KERNEL); + 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 f2fs_sb_info *sbi = F2FS_SB(inode->i_sb); + struct f2fs_inode_info *fi = F2FS_I(inode); + int name_index; + void *value = NULL; + size_t size = 0; + int error; + + if (!test_opt(sbi, POSIX_ACL)) + return 0; + if (S_ISLNK(inode->i_mode)) + return -EOPNOTSUPP; + + 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); + + kfree(value); + if (!error) + set_cached_acl(inode, type, acl); + + cond_clear_inode_flag(fi, FI_ACL_MODE); + return error; +} + +int f2fs_init_acl(struct inode *inode, struct inode *dir) +{ + struct posix_acl *acl = NULL; + struct f2fs_sb_info *sbi = F2FS_SB(dir->i_sb); + int error = 0; + + if (!S_ISLNK(inode->i_mode)) { + if (test_opt(sbi, POSIX_ACL)) { + acl = f2fs_get_acl(dir, ACL_TYPE_DEFAULT); + if (IS_ERR(acl)) + return PTR_ERR(acl); + } + if (!acl) + inode->i_mode &= ~current_umask(); + } + + if (test_opt(sbi, POSIX_ACL) && acl) { + + if (S_ISDIR(inode->i_mode)) { + error = f2fs_set_acl(inode, ACL_TYPE_DEFAULT, acl); + if (error) + goto cleanup; + } + error = posix_acl_create(&acl, GFP_KERNEL, &inode->i_mode); + if (error < 0) + return error; + if (error > 0) + error = f2fs_set_acl(inode, ACL_TYPE_ACCESS, acl); + } +cleanup: + posix_acl_release(acl); + return error; +} + +int f2fs_acl_chmod(struct inode *inode) +{ + struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb); + struct posix_acl *acl; + int error; + mode_t mode = get_inode_mode(inode); + + if (!test_opt(sbi, POSIX_ACL)) + return 0; + if (S_ISLNK(mode)) + return -EOPNOTSUPP; + + acl = f2fs_get_acl(inode, ACL_TYPE_ACCESS); + if (IS_ERR(acl) || !acl) + return PTR_ERR(acl); + + error = posix_acl_chmod(&acl, GFP_KERNEL, mode); + if (error) + return error; + error = f2fs_set_acl(inode, ACL_TYPE_ACCESS, acl); + posix_acl_release(acl); + return error; +} + +static size_t f2fs_xattr_list_acl(struct dentry *dentry, char *list, + size_t list_size, const char *name, size_t name_len, int type) +{ + struct f2fs_sb_info *sbi = F2FS_SB(dentry->d_sb); + const char *xname = POSIX_ACL_XATTR_DEFAULT; + size_t size; + + if (!test_opt(sbi, POSIX_ACL)) + return 0; + + if (type == ACL_TYPE_ACCESS) + xname = POSIX_ACL_XATTR_ACCESS; + + size = strlen(xname) + 1; + if (list && size <= list_size) + memcpy(list, xname, size); + return size; +} + +static int f2fs_xattr_get_acl(struct dentry *dentry, const char *name, + void *buffer, size_t size, int type) +{ + struct f2fs_sb_info *sbi = F2FS_SB(dentry->d_sb); + struct posix_acl *acl; + int error; + + if (strcmp(name, "") != 0) + return -EINVAL; + if (!test_opt(sbi, POSIX_ACL)) + return -EOPNOTSUPP; + + acl = f2fs_get_acl(dentry->d_inode, type); + if (IS_ERR(acl)) + return PTR_ERR(acl); + if (!acl) + return -ENODATA; + error = posix_acl_to_xattr(&init_user_ns, acl, buffer, size); + posix_acl_release(acl); + + return error; +} + +static int f2fs_xattr_set_acl(struct dentry *dentry, const char *name, + const void *value, size_t size, int flags, int type) +{ + struct f2fs_sb_info *sbi = F2FS_SB(dentry->d_sb); + struct inode *inode = dentry->d_inode; + struct posix_acl *acl = NULL; + int error; + + if (strcmp(name, "") != 0) + return -EINVAL; + if (!test_opt(sbi, POSIX_ACL)) + return -EOPNOTSUPP; + if (!inode_owner_or_capable(inode)) + return -EPERM; + + if (value) { + acl = posix_acl_from_xattr(&init_user_ns, value, size); + if (IS_ERR(acl)) + return PTR_ERR(acl); + if (acl) { + error = posix_acl_valid(acl); + if (error) + goto release_and_out; + } + } else { + acl = NULL; + } + + error = f2fs_set_acl(inode, type, acl); + +release_and_out: + posix_acl_release(acl); + return error; +} + +const struct xattr_handler f2fs_xattr_acl_default_handler = { + .prefix = POSIX_ACL_XATTR_DEFAULT, + .flags = ACL_TYPE_DEFAULT, + .list = f2fs_xattr_list_acl, + .get = f2fs_xattr_get_acl, + .set = f2fs_xattr_set_acl, +}; + +const struct xattr_handler f2fs_xattr_acl_access_handler = { + .prefix = POSIX_ACL_XATTR_ACCESS, + .flags = ACL_TYPE_ACCESS, + .list = f2fs_xattr_list_acl, + .get = f2fs_xattr_get_acl, + .set = f2fs_xattr_set_acl, +}; |