From 929fb014e041c6572c5e8c3686f1e32742b5b953 Mon Sep 17 00:00:00 2001 From: Tiger Yang Date: Fri, 14 Nov 2008 11:17:04 +0800 Subject: ocfs2: add POSIX ACL API This patch adds POSIX ACL(access control lists) APIs in ocfs2. We convert struct posix_acl to many ocfs2_acl_entry and regard them as an extended attribute entry. Signed-off-by: Tiger Yang Signed-off-by: Mark Fasheh --- fs/ocfs2/acl.c | 378 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 378 insertions(+) create mode 100644 fs/ocfs2/acl.c (limited to 'fs/ocfs2/acl.c') diff --git a/fs/ocfs2/acl.c b/fs/ocfs2/acl.c new file mode 100644 index 000000000000..62d0faad600b --- /dev/null +++ b/fs/ocfs2/acl.c @@ -0,0 +1,378 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * acl.c + * + * Copyright (C) 2004, 2008 Oracle. All rights reserved. + * + * CREDITS: + * Lots of code in this file is copy from linux/fs/ext3/acl.c. + * Copyright (C) 2001-2003 Andreas Gruenbacher, + * + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + */ + +#include +#include +#include + +#define MLOG_MASK_PREFIX ML_INODE +#include + +#include "ocfs2.h" +#include "alloc.h" +#include "dlmglue.h" +#include "file.h" +#include "ocfs2_fs.h" + +#include "xattr.h" +#include "acl.h" + +/* + * Convert from xattr value to acl struct. + */ +static struct posix_acl *ocfs2_acl_from_xattr(const void *value, size_t size) +{ + int n, count; + struct posix_acl *acl; + + if (!value) + return NULL; + if (size < sizeof(struct posix_acl_entry)) + return ERR_PTR(-EINVAL); + + count = size / sizeof(struct posix_acl_entry); + 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++) { + struct ocfs2_acl_entry *entry = + (struct ocfs2_acl_entry *)value; + + acl->a_entries[n].e_tag = le16_to_cpu(entry->e_tag); + acl->a_entries[n].e_perm = le16_to_cpu(entry->e_perm); + acl->a_entries[n].e_id = le32_to_cpu(entry->e_id); + value += sizeof(struct posix_acl_entry); + + } + return acl; +} + +/* + * Convert acl struct to xattr value. + */ +static void *ocfs2_acl_to_xattr(const struct posix_acl *acl, size_t *size) +{ + struct ocfs2_acl_entry *entry = NULL; + char *ocfs2_acl; + size_t n; + + *size = acl->a_count * sizeof(struct posix_acl_entry); + + ocfs2_acl = kmalloc(*size, GFP_NOFS); + if (!ocfs2_acl) + return ERR_PTR(-ENOMEM); + + entry = (struct ocfs2_acl_entry *)ocfs2_acl; + for (n = 0; n < acl->a_count; n++, entry++) { + entry->e_tag = cpu_to_le16(acl->a_entries[n].e_tag); + entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm); + entry->e_id = cpu_to_le32(acl->a_entries[n].e_id); + } + return ocfs2_acl; +} + +static struct posix_acl *ocfs2_get_acl_nolock(struct inode *inode, + int type, + struct buffer_head *di_bh) +{ + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); + int name_index; + char *value = NULL; + struct posix_acl *acl; + int retval; + + if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL)) + return NULL; + + switch (type) { + case ACL_TYPE_ACCESS: + name_index = OCFS2_XATTR_INDEX_POSIX_ACL_ACCESS; + break; + case ACL_TYPE_DEFAULT: + name_index = OCFS2_XATTR_INDEX_POSIX_ACL_DEFAULT; + break; + default: + return ERR_PTR(-EINVAL); + } + + retval = ocfs2_xattr_get_nolock(inode, di_bh, name_index, "", NULL, 0); + if (retval > 0) { + value = kmalloc(retval, GFP_NOFS); + if (!value) + return ERR_PTR(-ENOMEM); + retval = ocfs2_xattr_get_nolock(inode, di_bh, name_index, + "", value, retval); + } + + if (retval > 0) + acl = ocfs2_acl_from_xattr(value, retval); + else if (retval == -ENODATA || retval == 0) + acl = NULL; + else + acl = ERR_PTR(retval); + + kfree(value); + + return acl; +} + + +/* + * Get posix acl. + */ +static struct posix_acl *ocfs2_get_acl(struct inode *inode, int type) +{ + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); + struct buffer_head *di_bh = NULL; + struct posix_acl *acl; + int ret; + + if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL)) + return NULL; + + ret = ocfs2_inode_lock(inode, &di_bh, 0); + if (ret < 0) { + mlog_errno(ret); + acl = ERR_PTR(ret); + return acl; + } + + acl = ocfs2_get_acl_nolock(inode, type, di_bh); + + ocfs2_inode_unlock(inode, 0); + + brelse(di_bh); + + return acl; +} + +/* + * Set the access or default ACL of an inode. + */ +static int ocfs2_set_acl(handle_t *handle, + struct inode *inode, + struct buffer_head *di_bh, + int type, + struct posix_acl *acl, + struct ocfs2_alloc_context *meta_ac, + struct ocfs2_alloc_context *data_ac) +{ + int name_index; + void *value = NULL; + size_t size = 0; + int ret; + + if (S_ISLNK(inode->i_mode)) + return -EOPNOTSUPP; + + switch (type) { + case ACL_TYPE_ACCESS: + name_index = OCFS2_XATTR_INDEX_POSIX_ACL_ACCESS; + if (acl) { + mode_t mode = inode->i_mode; + ret = posix_acl_equiv_mode(acl, &mode); + if (ret < 0) + return ret; + else { + inode->i_mode = mode; + if (ret == 0) + acl = NULL; + } + } + break; + case ACL_TYPE_DEFAULT: + name_index = OCFS2_XATTR_INDEX_POSIX_ACL_DEFAULT; + if (!S_ISDIR(inode->i_mode)) + return acl ? -EACCES : 0; + break; + default: + return -EINVAL; + } + + if (acl) { + value = ocfs2_acl_to_xattr(acl, &size); + if (IS_ERR(value)) + return (int)PTR_ERR(value); + } + + if (handle) + ret = ocfs2_xattr_set_handle(handle, inode, di_bh, name_index, + "", value, size, 0, + meta_ac, data_ac); + else + ret = ocfs2_xattr_set(inode, name_index, "", value, size, 0); + + kfree(value); + + return ret; +} + +static size_t ocfs2_xattr_list_acl_access(struct inode *inode, + char *list, + size_t list_len, + const char *name, + size_t name_len) +{ + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); + const size_t size = sizeof(POSIX_ACL_XATTR_ACCESS); + + if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL)) + return 0; + + if (list && size <= list_len) + memcpy(list, POSIX_ACL_XATTR_ACCESS, size); + return size; +} + +static size_t ocfs2_xattr_list_acl_default(struct inode *inode, + char *list, + size_t list_len, + const char *name, + size_t name_len) +{ + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); + const size_t size = sizeof(POSIX_ACL_XATTR_DEFAULT); + + if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL)) + return 0; + + if (list && size <= list_len) + memcpy(list, POSIX_ACL_XATTR_DEFAULT, size); + return size; +} + +static int ocfs2_xattr_get_acl(struct inode *inode, + int type, + void *buffer, + size_t size) +{ + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); + struct posix_acl *acl; + int ret; + + if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL)) + return -EOPNOTSUPP; + + acl = ocfs2_get_acl(inode, type); + if (IS_ERR(acl)) + return PTR_ERR(acl); + if (acl == NULL) + return -ENODATA; + ret = posix_acl_to_xattr(acl, buffer, size); + posix_acl_release(acl); + + return ret; +} + +static int ocfs2_xattr_get_acl_access(struct inode *inode, + const char *name, + void *buffer, + size_t size) +{ + if (strcmp(name, "") != 0) + return -EINVAL; + return ocfs2_xattr_get_acl(inode, ACL_TYPE_ACCESS, buffer, size); +} + +static int ocfs2_xattr_get_acl_default(struct inode *inode, + const char *name, + void *buffer, + size_t size) +{ + if (strcmp(name, "") != 0) + return -EINVAL; + return ocfs2_xattr_get_acl(inode, ACL_TYPE_DEFAULT, buffer, size); +} + +static int ocfs2_xattr_set_acl(struct inode *inode, + int type, + const void *value, + size_t size) +{ + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); + struct posix_acl *acl; + int ret = 0; + + if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL)) + return -EOPNOTSUPP; + + if (!is_owner_or_cap(inode)) + return -EPERM; + + if (value) { + acl = posix_acl_from_xattr(value, size); + if (IS_ERR(acl)) + return PTR_ERR(acl); + else if (acl) { + ret = posix_acl_valid(acl); + if (ret) + goto cleanup; + } + } else + acl = NULL; + + ret = ocfs2_set_acl(NULL, inode, NULL, type, acl, NULL, NULL); + +cleanup: + posix_acl_release(acl); + return ret; +} + +static int ocfs2_xattr_set_acl_access(struct inode *inode, + const char *name, + const void *value, + size_t size, + int flags) +{ + if (strcmp(name, "") != 0) + return -EINVAL; + return ocfs2_xattr_set_acl(inode, ACL_TYPE_ACCESS, value, size); +} + +static int ocfs2_xattr_set_acl_default(struct inode *inode, + const char *name, + const void *value, + size_t size, + int flags) +{ + if (strcmp(name, "") != 0) + return -EINVAL; + return ocfs2_xattr_set_acl(inode, ACL_TYPE_DEFAULT, value, size); +} + +struct xattr_handler ocfs2_xattr_acl_access_handler = { + .prefix = POSIX_ACL_XATTR_ACCESS, + .list = ocfs2_xattr_list_acl_access, + .get = ocfs2_xattr_get_acl_access, + .set = ocfs2_xattr_set_acl_access, +}; + +struct xattr_handler ocfs2_xattr_acl_default_handler = { + .prefix = POSIX_ACL_XATTR_DEFAULT, + .list = ocfs2_xattr_list_acl_default, + .get = ocfs2_xattr_get_acl_default, + .set = ocfs2_xattr_set_acl_default, +}; -- cgit