linux/fs/afs/xattr.c
Thomas Gleixner b4d0d230cc treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public licence as published by
  the free software foundation either version 2 of the licence or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 114 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520170857.552531963@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:27:11 +02:00

428 lines
9.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/* Extended attribute handling for AFS. We use xattrs to get and set metadata
* instead of providing pioctl().
*
* Copyright (C) 2017 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*/
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/xattr.h>
#include "internal.h"
static const char afs_xattr_list[] =
"afs.acl\0"
"afs.cell\0"
"afs.fid\0"
"afs.volume\0"
"afs.yfs.acl\0"
"afs.yfs.acl_inherited\0"
"afs.yfs.acl_num_cleaned\0"
"afs.yfs.vol_acl";
/*
* Retrieve a list of the supported xattrs.
*/
ssize_t afs_listxattr(struct dentry *dentry, char *buffer, size_t size)
{
if (size == 0)
return sizeof(afs_xattr_list);
if (size < sizeof(afs_xattr_list))
return -ERANGE;
memcpy(buffer, afs_xattr_list, sizeof(afs_xattr_list));
return sizeof(afs_xattr_list);
}
/*
* Get a file's ACL.
*/
static int afs_xattr_get_acl(const struct xattr_handler *handler,
struct dentry *dentry,
struct inode *inode, const char *name,
void *buffer, size_t size)
{
struct afs_fs_cursor fc;
struct afs_status_cb *scb;
struct afs_vnode *vnode = AFS_FS_I(inode);
struct afs_acl *acl = NULL;
struct key *key;
int ret = -ENOMEM;
scb = kzalloc(sizeof(struct afs_status_cb), GFP_NOFS);
if (!scb)
goto error;
key = afs_request_key(vnode->volume->cell);
if (IS_ERR(key)) {
ret = PTR_ERR(key);
goto error_scb;
}
ret = -ERESTARTSYS;
if (afs_begin_vnode_operation(&fc, vnode, key, true)) {
afs_dataversion_t data_version = vnode->status.data_version;
while (afs_select_fileserver(&fc)) {
fc.cb_break = afs_calc_vnode_cb_break(vnode);
acl = afs_fs_fetch_acl(&fc, scb);
}
afs_check_for_remote_deletion(&fc, fc.vnode);
afs_vnode_commit_status(&fc, vnode, fc.cb_break,
&data_version, scb);
ret = afs_end_vnode_operation(&fc);
}
if (ret == 0) {
ret = acl->size;
if (size > 0) {
if (acl->size <= size)
memcpy(buffer, acl->data, acl->size);
else
ret = -ERANGE;
}
kfree(acl);
}
key_put(key);
error_scb:
kfree(scb);
error:
return ret;
}
/*
* Set a file's AFS3 ACL.
*/
static int afs_xattr_set_acl(const struct xattr_handler *handler,
struct dentry *dentry,
struct inode *inode, const char *name,
const void *buffer, size_t size, int flags)
{
struct afs_fs_cursor fc;
struct afs_status_cb *scb;
struct afs_vnode *vnode = AFS_FS_I(inode);
struct afs_acl *acl = NULL;
struct key *key;
int ret = -ENOMEM;
if (flags == XATTR_CREATE)
return -EINVAL;
scb = kzalloc(sizeof(struct afs_status_cb), GFP_NOFS);
if (!scb)
goto error;
acl = kmalloc(sizeof(*acl) + size, GFP_KERNEL);
if (!acl)
goto error_scb;
key = afs_request_key(vnode->volume->cell);
if (IS_ERR(key)) {
ret = PTR_ERR(key);
goto error_acl;
}
acl->size = size;
memcpy(acl->data, buffer, size);
ret = -ERESTARTSYS;
if (afs_begin_vnode_operation(&fc, vnode, key, true)) {
afs_dataversion_t data_version = vnode->status.data_version;
while (afs_select_fileserver(&fc)) {
fc.cb_break = afs_calc_vnode_cb_break(vnode);
afs_fs_store_acl(&fc, acl, scb);
}
afs_check_for_remote_deletion(&fc, fc.vnode);
afs_vnode_commit_status(&fc, vnode, fc.cb_break,
&data_version, scb);
ret = afs_end_vnode_operation(&fc);
}
key_put(key);
error_acl:
kfree(acl);
error_scb:
kfree(scb);
error:
return ret;
}
static const struct xattr_handler afs_xattr_afs_acl_handler = {
.name = "afs.acl",
.get = afs_xattr_get_acl,
.set = afs_xattr_set_acl,
};
/*
* Get a file's YFS ACL.
*/
static int afs_xattr_get_yfs(const struct xattr_handler *handler,
struct dentry *dentry,
struct inode *inode, const char *name,
void *buffer, size_t size)
{
struct afs_fs_cursor fc;
struct afs_status_cb *scb;
struct afs_vnode *vnode = AFS_FS_I(inode);
struct yfs_acl *yacl = NULL;
struct key *key;
char buf[16], *data;
int which = 0, dsize, ret = -ENOMEM;
if (strcmp(name, "acl") == 0)
which = 0;
else if (strcmp(name, "acl_inherited") == 0)
which = 1;
else if (strcmp(name, "acl_num_cleaned") == 0)
which = 2;
else if (strcmp(name, "vol_acl") == 0)
which = 3;
else
return -EOPNOTSUPP;
yacl = kzalloc(sizeof(struct yfs_acl), GFP_KERNEL);
if (!yacl)
goto error;
if (which == 0)
yacl->flags |= YFS_ACL_WANT_ACL;
else if (which == 3)
yacl->flags |= YFS_ACL_WANT_VOL_ACL;
scb = kzalloc(sizeof(struct afs_status_cb), GFP_NOFS);
if (!scb)
goto error_yacl;
key = afs_request_key(vnode->volume->cell);
if (IS_ERR(key)) {
ret = PTR_ERR(key);
goto error_scb;
}
ret = -ERESTARTSYS;
if (afs_begin_vnode_operation(&fc, vnode, key, true)) {
afs_dataversion_t data_version = vnode->status.data_version;
while (afs_select_fileserver(&fc)) {
fc.cb_break = afs_calc_vnode_cb_break(vnode);
yfs_fs_fetch_opaque_acl(&fc, yacl, scb);
}
afs_check_for_remote_deletion(&fc, fc.vnode);
afs_vnode_commit_status(&fc, vnode, fc.cb_break,
&data_version, scb);
ret = afs_end_vnode_operation(&fc);
}
if (ret < 0)
goto error_key;
switch (which) {
case 0:
data = yacl->acl->data;
dsize = yacl->acl->size;
break;
case 1:
data = buf;
dsize = snprintf(buf, sizeof(buf), "%u", yacl->inherit_flag);
break;
case 2:
data = buf;
dsize = snprintf(buf, sizeof(buf), "%u", yacl->num_cleaned);
break;
case 3:
data = yacl->vol_acl->data;
dsize = yacl->vol_acl->size;
break;
default:
ret = -EOPNOTSUPP;
goto error_key;
}
ret = dsize;
if (size > 0) {
if (dsize > size) {
ret = -ERANGE;
goto error_key;
}
memcpy(buffer, data, dsize);
}
error_key:
key_put(key);
error_scb:
kfree(scb);
error_yacl:
yfs_free_opaque_acl(yacl);
error:
return ret;
}
/*
* Set a file's YFS ACL.
*/
static int afs_xattr_set_yfs(const struct xattr_handler *handler,
struct dentry *dentry,
struct inode *inode, const char *name,
const void *buffer, size_t size, int flags)
{
struct afs_fs_cursor fc;
struct afs_status_cb *scb;
struct afs_vnode *vnode = AFS_FS_I(inode);
struct afs_acl *acl = NULL;
struct key *key;
int ret = -ENOMEM;
if (flags == XATTR_CREATE ||
strcmp(name, "acl") != 0)
return -EINVAL;
scb = kzalloc(sizeof(struct afs_status_cb), GFP_NOFS);
if (!scb)
goto error;
acl = kmalloc(sizeof(*acl) + size, GFP_KERNEL);
if (!acl)
goto error_scb;
acl->size = size;
memcpy(acl->data, buffer, size);
key = afs_request_key(vnode->volume->cell);
if (IS_ERR(key)) {
ret = PTR_ERR(key);
goto error_acl;
}
ret = -ERESTARTSYS;
if (afs_begin_vnode_operation(&fc, vnode, key, true)) {
afs_dataversion_t data_version = vnode->status.data_version;
while (afs_select_fileserver(&fc)) {
fc.cb_break = afs_calc_vnode_cb_break(vnode);
yfs_fs_store_opaque_acl2(&fc, acl, scb);
}
afs_check_for_remote_deletion(&fc, fc.vnode);
afs_vnode_commit_status(&fc, vnode, fc.cb_break,
&data_version, scb);
ret = afs_end_vnode_operation(&fc);
}
error_acl:
kfree(acl);
key_put(key);
error_scb:
kfree(scb);
error:
return ret;
}
static const struct xattr_handler afs_xattr_yfs_handler = {
.prefix = "afs.yfs.",
.get = afs_xattr_get_yfs,
.set = afs_xattr_set_yfs,
};
/*
* Get the name of the cell on which a file resides.
*/
static int afs_xattr_get_cell(const struct xattr_handler *handler,
struct dentry *dentry,
struct inode *inode, const char *name,
void *buffer, size_t size)
{
struct afs_vnode *vnode = AFS_FS_I(inode);
struct afs_cell *cell = vnode->volume->cell;
size_t namelen;
namelen = cell->name_len;
if (size == 0)
return namelen;
if (namelen > size)
return -ERANGE;
memcpy(buffer, cell->name, namelen);
return namelen;
}
static const struct xattr_handler afs_xattr_afs_cell_handler = {
.name = "afs.cell",
.get = afs_xattr_get_cell,
};
/*
* Get the volume ID, vnode ID and vnode uniquifier of a file as a sequence of
* hex numbers separated by colons.
*/
static int afs_xattr_get_fid(const struct xattr_handler *handler,
struct dentry *dentry,
struct inode *inode, const char *name,
void *buffer, size_t size)
{
struct afs_vnode *vnode = AFS_FS_I(inode);
char text[16 + 1 + 24 + 1 + 8 + 1];
size_t len;
/* The volume ID is 64-bit, the vnode ID is 96-bit and the
* uniquifier is 32-bit.
*/
len = sprintf(text, "%llx:", vnode->fid.vid);
if (vnode->fid.vnode_hi)
len += sprintf(text + len, "%x%016llx",
vnode->fid.vnode_hi, vnode->fid.vnode);
else
len += sprintf(text + len, "%llx", vnode->fid.vnode);
len += sprintf(text + len, ":%x", vnode->fid.unique);
if (size == 0)
return len;
if (len > size)
return -ERANGE;
memcpy(buffer, text, len);
return len;
}
static const struct xattr_handler afs_xattr_afs_fid_handler = {
.name = "afs.fid",
.get = afs_xattr_get_fid,
};
/*
* Get the name of the volume on which a file resides.
*/
static int afs_xattr_get_volume(const struct xattr_handler *handler,
struct dentry *dentry,
struct inode *inode, const char *name,
void *buffer, size_t size)
{
struct afs_vnode *vnode = AFS_FS_I(inode);
const char *volname = vnode->volume->name;
size_t namelen;
namelen = strlen(volname);
if (size == 0)
return namelen;
if (namelen > size)
return -ERANGE;
memcpy(buffer, volname, namelen);
return namelen;
}
static const struct xattr_handler afs_xattr_afs_volume_handler = {
.name = "afs.volume",
.get = afs_xattr_get_volume,
};
const struct xattr_handler *afs_xattr_handlers[] = {
&afs_xattr_afs_acl_handler,
&afs_xattr_afs_cell_handler,
&afs_xattr_afs_fid_handler,
&afs_xattr_afs_volume_handler,
&afs_xattr_yfs_handler, /* afs.yfs. prefix */
NULL
};