| /* |
| * 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, NULL); |
| |
| 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; |
| umode_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, |
| }; |