WSL2-Linux-Kernel/fs/cifs/xattr.c

496 строки
13 KiB
C

// SPDX-License-Identifier: LGPL-2.1
/*
*
* Copyright (c) International Business Machines Corp., 2003, 2007
* Author(s): Steve French (sfrench@us.ibm.com)
*
*/
#include <linux/fs.h>
#include <linux/posix_acl_xattr.h>
#include <linux/slab.h>
#include <linux/xattr.h>
#include "cifsfs.h"
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_debug.h"
#include "cifs_fs_sb.h"
#include "cifs_unicode.h"
#include "cifs_ioctl.h"
#define MAX_EA_VALUE_SIZE CIFSMaxBufSize
#define CIFS_XATTR_CIFS_ACL "system.cifs_acl" /* DACL only */
#define CIFS_XATTR_CIFS_NTSD "system.cifs_ntsd" /* owner plus DACL */
#define CIFS_XATTR_CIFS_NTSD_FULL "system.cifs_ntsd_full" /* owner/DACL/SACL */
#define CIFS_XATTR_ATTRIB "cifs.dosattrib" /* full name: user.cifs.dosattrib */
#define CIFS_XATTR_CREATETIME "cifs.creationtime" /* user.cifs.creationtime */
/*
* Although these three are just aliases for the above, need to move away from
* confusing users and using the 20+ year old term 'cifs' when it is no longer
* secure, replaced by SMB2 (then even more highly secure SMB3) many years ago
*/
#define SMB3_XATTR_CIFS_ACL "system.smb3_acl" /* DACL only */
#define SMB3_XATTR_CIFS_NTSD "system.smb3_ntsd" /* owner plus DACL */
#define SMB3_XATTR_CIFS_NTSD_FULL "system.smb3_ntsd_full" /* owner/DACL/SACL */
#define SMB3_XATTR_ATTRIB "smb3.dosattrib" /* full name: user.smb3.dosattrib */
#define SMB3_XATTR_CREATETIME "smb3.creationtime" /* user.smb3.creationtime */
/* BB need to add server (Samba e.g) support for security and trusted prefix */
enum { XATTR_USER, XATTR_CIFS_ACL, XATTR_ACL_ACCESS, XATTR_ACL_DEFAULT,
XATTR_CIFS_NTSD, XATTR_CIFS_NTSD_FULL };
static int cifs_attrib_set(unsigned int xid, struct cifs_tcon *pTcon,
struct inode *inode, const char *full_path,
const void *value, size_t size)
{
ssize_t rc = -EOPNOTSUPP;
__u32 *pattrib = (__u32 *)value;
__u32 attrib;
FILE_BASIC_INFO info_buf;
if ((value == NULL) || (size != sizeof(__u32)))
return -ERANGE;
memset(&info_buf, 0, sizeof(info_buf));
attrib = *pattrib;
info_buf.Attributes = cpu_to_le32(attrib);
if (pTcon->ses->server->ops->set_file_info)
rc = pTcon->ses->server->ops->set_file_info(inode, full_path,
&info_buf, xid);
if (rc == 0)
CIFS_I(inode)->cifsAttrs = attrib;
return rc;
}
static int cifs_creation_time_set(unsigned int xid, struct cifs_tcon *pTcon,
struct inode *inode, const char *full_path,
const void *value, size_t size)
{
ssize_t rc = -EOPNOTSUPP;
__u64 *pcreation_time = (__u64 *)value;
__u64 creation_time;
FILE_BASIC_INFO info_buf;
if ((value == NULL) || (size != sizeof(__u64)))
return -ERANGE;
memset(&info_buf, 0, sizeof(info_buf));
creation_time = *pcreation_time;
info_buf.CreationTime = cpu_to_le64(creation_time);
if (pTcon->ses->server->ops->set_file_info)
rc = pTcon->ses->server->ops->set_file_info(inode, full_path,
&info_buf, xid);
if (rc == 0)
CIFS_I(inode)->createtime = creation_time;
return rc;
}
static int cifs_xattr_set(const struct xattr_handler *handler,
struct user_namespace *mnt_userns,
struct dentry *dentry, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
{
int rc = -EOPNOTSUPP;
unsigned int xid;
struct super_block *sb = dentry->d_sb;
struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
struct tcon_link *tlink;
struct cifs_tcon *pTcon;
const char *full_path;
void *page;
tlink = cifs_sb_tlink(cifs_sb);
if (IS_ERR(tlink))
return PTR_ERR(tlink);
pTcon = tlink_tcon(tlink);
xid = get_xid();
page = alloc_dentry_path();
full_path = build_path_from_dentry(dentry, page);
if (IS_ERR(full_path)) {
rc = PTR_ERR(full_path);
goto out;
}
/* return dos attributes as pseudo xattr */
/* return alt name if available as pseudo attr */
/* if proc/fs/cifs/streamstoxattr is set then
search server for EAs or streams to
returns as xattrs */
if (size > MAX_EA_VALUE_SIZE) {
cifs_dbg(FYI, "size of EA value too large\n");
rc = -EOPNOTSUPP;
goto out;
}
switch (handler->flags) {
case XATTR_USER:
cifs_dbg(FYI, "%s:setting user xattr %s\n", __func__, name);
if ((strcmp(name, CIFS_XATTR_ATTRIB) == 0) ||
(strcmp(name, SMB3_XATTR_ATTRIB) == 0)) {
rc = cifs_attrib_set(xid, pTcon, inode, full_path,
value, size);
if (rc == 0) /* force revalidate of the inode */
CIFS_I(inode)->time = 0;
break;
} else if ((strcmp(name, CIFS_XATTR_CREATETIME) == 0) ||
(strcmp(name, SMB3_XATTR_CREATETIME) == 0)) {
rc = cifs_creation_time_set(xid, pTcon, inode,
full_path, value, size);
if (rc == 0) /* force revalidate of the inode */
CIFS_I(inode)->time = 0;
break;
}
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
goto out;
if (pTcon->ses->server->ops->set_EA)
rc = pTcon->ses->server->ops->set_EA(xid, pTcon,
full_path, name, value, (__u16)size,
cifs_sb->local_nls, cifs_sb);
break;
case XATTR_CIFS_ACL:
case XATTR_CIFS_NTSD:
case XATTR_CIFS_NTSD_FULL: {
struct cifs_ntsd *pacl;
if (!value)
goto out;
pacl = kmalloc(size, GFP_KERNEL);
if (!pacl) {
rc = -ENOMEM;
} else {
memcpy(pacl, value, size);
if (pTcon->ses->server->ops->set_acl) {
int aclflags = 0;
rc = 0;
switch (handler->flags) {
case XATTR_CIFS_NTSD_FULL:
aclflags = (CIFS_ACL_OWNER |
CIFS_ACL_GROUP |
CIFS_ACL_DACL |
CIFS_ACL_SACL);
break;
case XATTR_CIFS_NTSD:
aclflags = (CIFS_ACL_OWNER |
CIFS_ACL_GROUP |
CIFS_ACL_DACL);
break;
case XATTR_CIFS_ACL:
default:
aclflags = CIFS_ACL_DACL;
}
rc = pTcon->ses->server->ops->set_acl(pacl,
size, inode, full_path, aclflags);
} else {
rc = -EOPNOTSUPP;
}
if (rc == 0) /* force revalidate of the inode */
CIFS_I(inode)->time = 0;
kfree(pacl);
}
break;
}
}
out:
free_dentry_path(page);
free_xid(xid);
cifs_put_tlink(tlink);
return rc;
}
static int cifs_attrib_get(struct dentry *dentry,
struct inode *inode, void *value,
size_t size)
{
ssize_t rc;
__u32 *pattribute;
rc = cifs_revalidate_dentry_attr(dentry);
if (rc)
return rc;
if ((value == NULL) || (size == 0))
return sizeof(__u32);
else if (size < sizeof(__u32))
return -ERANGE;
/* return dos attributes as pseudo xattr */
pattribute = (__u32 *)value;
*pattribute = CIFS_I(inode)->cifsAttrs;
return sizeof(__u32);
}
static int cifs_creation_time_get(struct dentry *dentry, struct inode *inode,
void *value, size_t size)
{
ssize_t rc;
__u64 *pcreatetime;
rc = cifs_revalidate_dentry_attr(dentry);
if (rc)
return rc;
if ((value == NULL) || (size == 0))
return sizeof(__u64);
else if (size < sizeof(__u64))
return -ERANGE;
/* return dos attributes as pseudo xattr */
pcreatetime = (__u64 *)value;
*pcreatetime = CIFS_I(inode)->createtime;
return sizeof(__u64);
}
static int cifs_xattr_get(const struct xattr_handler *handler,
struct dentry *dentry, struct inode *inode,
const char *name, void *value, size_t size)
{
ssize_t rc = -EOPNOTSUPP;
unsigned int xid;
struct super_block *sb = dentry->d_sb;
struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
struct tcon_link *tlink;
struct cifs_tcon *pTcon;
const char *full_path;
void *page;
tlink = cifs_sb_tlink(cifs_sb);
if (IS_ERR(tlink))
return PTR_ERR(tlink);
pTcon = tlink_tcon(tlink);
xid = get_xid();
page = alloc_dentry_path();
full_path = build_path_from_dentry(dentry, page);
if (IS_ERR(full_path)) {
rc = PTR_ERR(full_path);
goto out;
}
/* return alt name if available as pseudo attr */
switch (handler->flags) {
case XATTR_USER:
cifs_dbg(FYI, "%s:querying user xattr %s\n", __func__, name);
if ((strcmp(name, CIFS_XATTR_ATTRIB) == 0) ||
(strcmp(name, SMB3_XATTR_ATTRIB) == 0)) {
rc = cifs_attrib_get(dentry, inode, value, size);
break;
} else if ((strcmp(name, CIFS_XATTR_CREATETIME) == 0) ||
(strcmp(name, SMB3_XATTR_CREATETIME) == 0)) {
rc = cifs_creation_time_get(dentry, inode, value, size);
break;
}
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
goto out;
if (pTcon->ses->server->ops->query_all_EAs)
rc = pTcon->ses->server->ops->query_all_EAs(xid, pTcon,
full_path, name, value, size, cifs_sb);
break;
case XATTR_CIFS_ACL:
case XATTR_CIFS_NTSD:
case XATTR_CIFS_NTSD_FULL: {
/*
* fetch owner, DACL, and SACL if asked for full descriptor,
* fetch owner and DACL otherwise
*/
u32 acllen, extra_info;
struct cifs_ntsd *pacl;
if (pTcon->ses->server->ops->get_acl == NULL)
goto out; /* rc already EOPNOTSUPP */
if (handler->flags == XATTR_CIFS_NTSD_FULL) {
extra_info = SACL_SECINFO;
} else {
extra_info = 0;
}
pacl = pTcon->ses->server->ops->get_acl(cifs_sb,
inode, full_path, &acllen, extra_info);
if (IS_ERR(pacl)) {
rc = PTR_ERR(pacl);
cifs_dbg(VFS, "%s: error %zd getting sec desc\n",
__func__, rc);
} else {
if (value) {
if (acllen > size)
acllen = -ERANGE;
else
memcpy(value, pacl, acllen);
}
rc = acllen;
kfree(pacl);
}
break;
}
}
/* We could add an additional check for streams ie
if proc/fs/cifs/streamstoxattr is set then
search server for EAs or streams to
returns as xattrs */
if (rc == -EINVAL)
rc = -EOPNOTSUPP;
out:
free_dentry_path(page);
free_xid(xid);
cifs_put_tlink(tlink);
return rc;
}
ssize_t cifs_listxattr(struct dentry *direntry, char *data, size_t buf_size)
{
ssize_t rc = -EOPNOTSUPP;
unsigned int xid;
struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
struct tcon_link *tlink;
struct cifs_tcon *pTcon;
const char *full_path;
void *page;
if (unlikely(cifs_forced_shutdown(cifs_sb)))
return -EIO;
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
return -EOPNOTSUPP;
tlink = cifs_sb_tlink(cifs_sb);
if (IS_ERR(tlink))
return PTR_ERR(tlink);
pTcon = tlink_tcon(tlink);
xid = get_xid();
page = alloc_dentry_path();
full_path = build_path_from_dentry(direntry, page);
if (IS_ERR(full_path)) {
rc = PTR_ERR(full_path);
goto list_ea_exit;
}
/* return dos attributes as pseudo xattr */
/* return alt name if available as pseudo attr */
/* if proc/fs/cifs/streamstoxattr is set then
search server for EAs or streams to
returns as xattrs */
if (pTcon->ses->server->ops->query_all_EAs)
rc = pTcon->ses->server->ops->query_all_EAs(xid, pTcon,
full_path, NULL, data, buf_size, cifs_sb);
list_ea_exit:
free_dentry_path(page);
free_xid(xid);
cifs_put_tlink(tlink);
return rc;
}
static const struct xattr_handler cifs_user_xattr_handler = {
.prefix = XATTR_USER_PREFIX,
.flags = XATTR_USER,
.get = cifs_xattr_get,
.set = cifs_xattr_set,
};
/* os2.* attributes are treated like user.* attributes */
static const struct xattr_handler cifs_os2_xattr_handler = {
.prefix = XATTR_OS2_PREFIX,
.flags = XATTR_USER,
.get = cifs_xattr_get,
.set = cifs_xattr_set,
};
static const struct xattr_handler cifs_cifs_acl_xattr_handler = {
.name = CIFS_XATTR_CIFS_ACL,
.flags = XATTR_CIFS_ACL,
.get = cifs_xattr_get,
.set = cifs_xattr_set,
};
/*
* Although this is just an alias for the above, need to move away from
* confusing users and using the 20 year old term 'cifs' when it is no
* longer secure and was replaced by SMB2/SMB3 a long time ago, and
* SMB3 and later are highly secure.
*/
static const struct xattr_handler smb3_acl_xattr_handler = {
.name = SMB3_XATTR_CIFS_ACL,
.flags = XATTR_CIFS_ACL,
.get = cifs_xattr_get,
.set = cifs_xattr_set,
};
static const struct xattr_handler cifs_cifs_ntsd_xattr_handler = {
.name = CIFS_XATTR_CIFS_NTSD,
.flags = XATTR_CIFS_NTSD,
.get = cifs_xattr_get,
.set = cifs_xattr_set,
};
/*
* Although this is just an alias for the above, need to move away from
* confusing users and using the 20 year old term 'cifs' when it is no
* longer secure and was replaced by SMB2/SMB3 a long time ago, and
* SMB3 and later are highly secure.
*/
static const struct xattr_handler smb3_ntsd_xattr_handler = {
.name = SMB3_XATTR_CIFS_NTSD,
.flags = XATTR_CIFS_NTSD,
.get = cifs_xattr_get,
.set = cifs_xattr_set,
};
static const struct xattr_handler cifs_cifs_ntsd_full_xattr_handler = {
.name = CIFS_XATTR_CIFS_NTSD_FULL,
.flags = XATTR_CIFS_NTSD_FULL,
.get = cifs_xattr_get,
.set = cifs_xattr_set,
};
/*
* Although this is just an alias for the above, need to move away from
* confusing users and using the 20 year old term 'cifs' when it is no
* longer secure and was replaced by SMB2/SMB3 a long time ago, and
* SMB3 and later are highly secure.
*/
static const struct xattr_handler smb3_ntsd_full_xattr_handler = {
.name = SMB3_XATTR_CIFS_NTSD_FULL,
.flags = XATTR_CIFS_NTSD_FULL,
.get = cifs_xattr_get,
.set = cifs_xattr_set,
};
const struct xattr_handler *cifs_xattr_handlers[] = {
&cifs_user_xattr_handler,
&cifs_os2_xattr_handler,
&cifs_cifs_acl_xattr_handler,
&smb3_acl_xattr_handler, /* alias for above since avoiding "cifs" */
&cifs_cifs_ntsd_xattr_handler,
&smb3_ntsd_xattr_handler, /* alias for above since avoiding "cifs" */
&cifs_cifs_ntsd_full_xattr_handler,
&smb3_ntsd_full_xattr_handler, /* alias for above since avoiding "cifs" */
#ifdef CONFIG_FS_POSIX_ACL
&posix_acl_access_xattr_handler,
&posix_acl_default_xattr_handler,
#endif
NULL
};