2007-04-27 00:57:07 +02:00
|
|
|
/* AFS security handling
|
|
|
|
*
|
|
|
|
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
|
|
|
|
* Written by David Howells (dhowells@redhat.com)
|
|
|
|
*
|
|
|
|
* This program is free software; you can redistribute it and/or
|
|
|
|
* modify it under the terms of the GNU General Public License
|
|
|
|
* as published by the Free Software Foundation; either version
|
|
|
|
* 2 of the License, or (at your option) any later version.
|
|
|
|
*/
|
|
|
|
|
|
|
|
#include <linux/init.h>
|
|
|
|
#include <linux/slab.h>
|
|
|
|
#include <linux/fs.h>
|
|
|
|
#include <linux/ctype.h>
|
Detach sched.h from mm.h
First thing mm.h does is including sched.h solely for can_do_mlock() inline
function which has "current" dereference inside. By dealing with can_do_mlock()
mm.h can be detached from sched.h which is good. See below, why.
This patch
a) removes unconditional inclusion of sched.h from mm.h
b) makes can_do_mlock() normal function in mm/mlock.c
c) exports can_do_mlock() to not break compilation
d) adds sched.h inclusions back to files that were getting it indirectly.
e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were
getting them indirectly
Net result is:
a) mm.h users would get less code to open, read, preprocess, parse, ... if
they don't need sched.h
b) sched.h stops being dependency for significant number of files:
on x86_64 allmodconfig touching sched.h results in recompile of 4083 files,
after patch it's only 3744 (-8.3%).
Cross-compile tested on
all arm defconfigs, all mips defconfigs, all powerpc defconfigs,
alpha alpha-up
arm
i386 i386-up i386-defconfig i386-allnoconfig
ia64 ia64-up
m68k
mips
parisc parisc-up
powerpc powerpc-up
s390 s390-up
sparc sparc-up
sparc64 sparc64-up
um-x86_64
x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig
as well as my two usual configs.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-20 23:22:52 +02:00
|
|
|
#include <linux/sched.h>
|
2007-04-27 00:57:07 +02:00
|
|
|
#include <keys/rxrpc-type.h>
|
|
|
|
#include "internal.h"
|
|
|
|
|
|
|
|
/*
|
|
|
|
* get a key
|
|
|
|
*/
|
|
|
|
struct key *afs_request_key(struct afs_cell *cell)
|
|
|
|
{
|
|
|
|
struct key *key;
|
|
|
|
|
|
|
|
_enter("{%x}", key_serial(cell->anonymous_key));
|
|
|
|
|
|
|
|
_debug("key %s", cell->anonymous_key->description);
|
|
|
|
key = request_key(&key_type_rxrpc, cell->anonymous_key->description,
|
|
|
|
NULL);
|
|
|
|
if (IS_ERR(key)) {
|
|
|
|
if (PTR_ERR(key) != -ENOKEY) {
|
|
|
|
_leave(" = %ld", PTR_ERR(key));
|
|
|
|
return key;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* act as anonymous user */
|
|
|
|
_leave(" = {%x} [anon]", key_serial(cell->anonymous_key));
|
|
|
|
return key_get(cell->anonymous_key);
|
|
|
|
} else {
|
|
|
|
/* act as authorised user */
|
|
|
|
_leave(" = {%x} [auth]", key_serial(key));
|
|
|
|
return key;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* dispose of a permits list
|
|
|
|
*/
|
|
|
|
void afs_zap_permits(struct rcu_head *rcu)
|
|
|
|
{
|
|
|
|
struct afs_permits *permits =
|
|
|
|
container_of(rcu, struct afs_permits, rcu);
|
|
|
|
int loop;
|
|
|
|
|
|
|
|
_enter("{%d}", permits->count);
|
|
|
|
|
|
|
|
for (loop = permits->count - 1; loop >= 0; loop--)
|
|
|
|
key_put(permits->permits[loop].key);
|
|
|
|
kfree(permits);
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* dispose of a permits list in which all the key pointers have been copied
|
|
|
|
*/
|
|
|
|
static void afs_dispose_of_permits(struct rcu_head *rcu)
|
|
|
|
{
|
|
|
|
struct afs_permits *permits =
|
|
|
|
container_of(rcu, struct afs_permits, rcu);
|
|
|
|
|
|
|
|
_enter("{%d}", permits->count);
|
|
|
|
|
|
|
|
kfree(permits);
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* get the authorising vnode - this is the specified inode itself if it's a
|
|
|
|
* directory or it's the parent directory if the specified inode is a file or
|
|
|
|
* symlink
|
|
|
|
* - the caller must release the ref on the inode
|
|
|
|
*/
|
|
|
|
static struct afs_vnode *afs_get_auth_inode(struct afs_vnode *vnode,
|
|
|
|
struct key *key)
|
|
|
|
{
|
|
|
|
struct afs_vnode *auth_vnode;
|
|
|
|
struct inode *auth_inode;
|
|
|
|
|
|
|
|
_enter("");
|
|
|
|
|
|
|
|
if (S_ISDIR(vnode->vfs_inode.i_mode)) {
|
|
|
|
auth_inode = igrab(&vnode->vfs_inode);
|
|
|
|
ASSERT(auth_inode != NULL);
|
|
|
|
} else {
|
|
|
|
auth_inode = afs_iget(vnode->vfs_inode.i_sb, key,
|
2007-04-27 00:59:35 +02:00
|
|
|
&vnode->status.parent, NULL, NULL);
|
2007-04-27 00:57:07 +02:00
|
|
|
if (IS_ERR(auth_inode))
|
2008-02-07 09:15:26 +01:00
|
|
|
return ERR_CAST(auth_inode);
|
2007-04-27 00:57:07 +02:00
|
|
|
}
|
|
|
|
|
|
|
|
auth_vnode = AFS_FS_I(auth_inode);
|
|
|
|
_leave(" = {%x}", auth_vnode->fid.vnode);
|
|
|
|
return auth_vnode;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* clear the permit cache on a directory vnode
|
|
|
|
*/
|
|
|
|
void afs_clear_permits(struct afs_vnode *vnode)
|
|
|
|
{
|
|
|
|
struct afs_permits *permits;
|
|
|
|
|
2007-05-09 11:33:45 +02:00
|
|
|
_enter("{%x:%u}", vnode->fid.vid, vnode->fid.vnode);
|
2007-04-27 00:57:07 +02:00
|
|
|
|
|
|
|
mutex_lock(&vnode->permits_lock);
|
|
|
|
permits = vnode->permits;
|
|
|
|
rcu_assign_pointer(vnode->permits, NULL);
|
|
|
|
mutex_unlock(&vnode->permits_lock);
|
|
|
|
|
|
|
|
if (permits)
|
|
|
|
call_rcu(&permits->rcu, afs_zap_permits);
|
|
|
|
_leave("");
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* add the result obtained for a vnode to its or its parent directory's cache
|
|
|
|
* for the key used to access it
|
|
|
|
*/
|
|
|
|
void afs_cache_permit(struct afs_vnode *vnode, struct key *key, long acl_order)
|
|
|
|
{
|
|
|
|
struct afs_permits *permits, *xpermits;
|
|
|
|
struct afs_permit *permit;
|
|
|
|
struct afs_vnode *auth_vnode;
|
|
|
|
int count, loop;
|
|
|
|
|
2007-05-09 11:33:45 +02:00
|
|
|
_enter("{%x:%u},%x,%lx",
|
|
|
|
vnode->fid.vid, vnode->fid.vnode, key_serial(key), acl_order);
|
2007-04-27 00:57:07 +02:00
|
|
|
|
|
|
|
auth_vnode = afs_get_auth_inode(vnode, key);
|
|
|
|
if (IS_ERR(auth_vnode)) {
|
|
|
|
_leave(" [get error %ld]", PTR_ERR(auth_vnode));
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
mutex_lock(&auth_vnode->permits_lock);
|
|
|
|
|
|
|
|
/* guard against a rename being detected whilst we waited for the
|
|
|
|
* lock */
|
|
|
|
if (memcmp(&auth_vnode->fid, &vnode->status.parent,
|
|
|
|
sizeof(struct afs_fid)) != 0) {
|
|
|
|
_debug("renamed");
|
|
|
|
goto out_unlock;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* have to be careful as the directory's callback may be broken between
|
|
|
|
* us receiving the status we're trying to cache and us getting the
|
|
|
|
* lock to update the cache for the status */
|
|
|
|
if (auth_vnode->acl_order - acl_order > 0) {
|
|
|
|
_debug("ACL changed?");
|
|
|
|
goto out_unlock;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* always update the anonymous mask */
|
|
|
|
_debug("anon access %x", vnode->status.anon_access);
|
|
|
|
auth_vnode->status.anon_access = vnode->status.anon_access;
|
|
|
|
if (key == vnode->volume->cell->anonymous_key)
|
|
|
|
goto out_unlock;
|
|
|
|
|
|
|
|
xpermits = auth_vnode->permits;
|
|
|
|
count = 0;
|
|
|
|
if (xpermits) {
|
|
|
|
/* see if the permit is already in the list
|
|
|
|
* - if it is then we just amend the list
|
|
|
|
*/
|
|
|
|
count = xpermits->count;
|
|
|
|
permit = xpermits->permits;
|
|
|
|
for (loop = count; loop > 0; loop--) {
|
|
|
|
if (permit->key == key) {
|
|
|
|
permit->access_mask =
|
|
|
|
vnode->status.caller_access;
|
|
|
|
goto out_unlock;
|
|
|
|
}
|
|
|
|
permit++;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
permits = kmalloc(sizeof(*permits) + sizeof(*permit) * (count + 1),
|
|
|
|
GFP_NOFS);
|
|
|
|
if (!permits)
|
|
|
|
goto out_unlock;
|
|
|
|
|
|
|
|
memcpy(permits->permits, xpermits->permits,
|
|
|
|
count * sizeof(struct afs_permit));
|
|
|
|
|
|
|
|
_debug("key %x access %x",
|
|
|
|
key_serial(key), vnode->status.caller_access);
|
|
|
|
permits->permits[count].access_mask = vnode->status.caller_access;
|
|
|
|
permits->permits[count].key = key_get(key);
|
|
|
|
permits->count = count + 1;
|
|
|
|
|
|
|
|
rcu_assign_pointer(auth_vnode->permits, permits);
|
|
|
|
if (xpermits)
|
|
|
|
call_rcu(&xpermits->rcu, afs_dispose_of_permits);
|
|
|
|
|
|
|
|
out_unlock:
|
|
|
|
mutex_unlock(&auth_vnode->permits_lock);
|
|
|
|
iput(&auth_vnode->vfs_inode);
|
|
|
|
_leave("");
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* check with the fileserver to see if the directory or parent directory is
|
|
|
|
* permitted to be accessed with this authorisation, and if so, what access it
|
|
|
|
* is granted
|
|
|
|
*/
|
|
|
|
static int afs_check_permit(struct afs_vnode *vnode, struct key *key,
|
|
|
|
afs_access_t *_access)
|
|
|
|
{
|
|
|
|
struct afs_permits *permits;
|
|
|
|
struct afs_permit *permit;
|
|
|
|
struct afs_vnode *auth_vnode;
|
|
|
|
bool valid;
|
|
|
|
int loop, ret;
|
|
|
|
|
2007-05-09 11:33:45 +02:00
|
|
|
_enter("{%x:%u},%x",
|
|
|
|
vnode->fid.vid, vnode->fid.vnode, key_serial(key));
|
2007-04-27 00:57:07 +02:00
|
|
|
|
|
|
|
auth_vnode = afs_get_auth_inode(vnode, key);
|
|
|
|
if (IS_ERR(auth_vnode)) {
|
|
|
|
*_access = 0;
|
|
|
|
_leave(" = %ld", PTR_ERR(auth_vnode));
|
|
|
|
return PTR_ERR(auth_vnode);
|
|
|
|
}
|
|
|
|
|
|
|
|
ASSERT(S_ISDIR(auth_vnode->vfs_inode.i_mode));
|
|
|
|
|
|
|
|
/* check the permits to see if we've got one yet */
|
|
|
|
if (key == auth_vnode->volume->cell->anonymous_key) {
|
|
|
|
_debug("anon");
|
|
|
|
*_access = auth_vnode->status.anon_access;
|
|
|
|
valid = true;
|
|
|
|
} else {
|
|
|
|
valid = false;
|
|
|
|
rcu_read_lock();
|
|
|
|
permits = rcu_dereference(auth_vnode->permits);
|
|
|
|
if (permits) {
|
|
|
|
permit = permits->permits;
|
|
|
|
for (loop = permits->count; loop > 0; loop--) {
|
|
|
|
if (permit->key == key) {
|
|
|
|
_debug("found in cache");
|
|
|
|
*_access = permit->access_mask;
|
|
|
|
valid = true;
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
permit++;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
rcu_read_unlock();
|
|
|
|
}
|
|
|
|
|
|
|
|
if (!valid) {
|
|
|
|
/* check the status on the file we're actually interested in
|
|
|
|
* (the post-processing will cache the result on auth_vnode) */
|
|
|
|
_debug("no valid permit");
|
|
|
|
|
|
|
|
set_bit(AFS_VNODE_CB_BROKEN, &vnode->flags);
|
|
|
|
ret = afs_vnode_fetch_status(vnode, auth_vnode, key);
|
|
|
|
if (ret < 0) {
|
|
|
|
iput(&auth_vnode->vfs_inode);
|
|
|
|
*_access = 0;
|
|
|
|
_leave(" = %d", ret);
|
|
|
|
return ret;
|
|
|
|
}
|
2007-05-09 11:33:45 +02:00
|
|
|
*_access = vnode->status.caller_access;
|
2007-04-27 00:57:07 +02:00
|
|
|
}
|
|
|
|
|
|
|
|
iput(&auth_vnode->vfs_inode);
|
|
|
|
_leave(" = 0 [access %x]", *_access);
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* check the permissions on an AFS file
|
|
|
|
* - AFS ACLs are attached to directories only, and a file is controlled by its
|
|
|
|
* parent directory's ACL
|
|
|
|
*/
|
2008-07-16 03:03:57 +02:00
|
|
|
int afs_permission(struct inode *inode, int mask)
|
2007-04-27 00:57:07 +02:00
|
|
|
{
|
|
|
|
struct afs_vnode *vnode = AFS_FS_I(inode);
|
2008-02-08 13:20:53 +01:00
|
|
|
afs_access_t uninitialized_var(access);
|
2007-04-27 00:57:07 +02:00
|
|
|
struct key *key;
|
|
|
|
int ret;
|
|
|
|
|
2007-05-09 11:33:45 +02:00
|
|
|
_enter("{{%x:%u},%lx},%x,",
|
2007-04-27 00:59:35 +02:00
|
|
|
vnode->fid.vid, vnode->fid.vnode, vnode->flags, mask);
|
2007-04-27 00:57:07 +02:00
|
|
|
|
|
|
|
key = afs_request_key(vnode->volume->cell);
|
|
|
|
if (IS_ERR(key)) {
|
|
|
|
_leave(" = %ld [key]", PTR_ERR(key));
|
|
|
|
return PTR_ERR(key);
|
|
|
|
}
|
|
|
|
|
2007-04-27 00:59:35 +02:00
|
|
|
/* if the promise has expired, we need to check the server again */
|
|
|
|
if (!vnode->cb_promised) {
|
|
|
|
_debug("not promised");
|
|
|
|
ret = afs_vnode_fetch_status(vnode, NULL, key);
|
|
|
|
if (ret < 0)
|
|
|
|
goto error;
|
|
|
|
_debug("new promise [fl=%lx]", vnode->flags);
|
|
|
|
}
|
|
|
|
|
2007-04-27 00:57:07 +02:00
|
|
|
/* check the permits to see if we've got one yet */
|
|
|
|
ret = afs_check_permit(vnode, key, &access);
|
2007-04-27 00:59:35 +02:00
|
|
|
if (ret < 0)
|
|
|
|
goto error;
|
2007-04-27 00:57:07 +02:00
|
|
|
|
|
|
|
/* interpret the access mask */
|
|
|
|
_debug("REQ %x ACC %x on %s",
|
|
|
|
mask, access, S_ISDIR(inode->i_mode) ? "dir" : "file");
|
|
|
|
|
|
|
|
if (S_ISDIR(inode->i_mode)) {
|
|
|
|
if (mask & MAY_EXEC) {
|
|
|
|
if (!(access & AFS_ACE_LOOKUP))
|
|
|
|
goto permission_denied;
|
|
|
|
} else if (mask & MAY_READ) {
|
|
|
|
if (!(access & AFS_ACE_READ))
|
|
|
|
goto permission_denied;
|
|
|
|
} else if (mask & MAY_WRITE) {
|
|
|
|
if (!(access & (AFS_ACE_DELETE | /* rmdir, unlink, rename from */
|
|
|
|
AFS_ACE_INSERT | /* create, mkdir, symlink, rename to */
|
|
|
|
AFS_ACE_WRITE))) /* chmod */
|
|
|
|
goto permission_denied;
|
|
|
|
} else {
|
|
|
|
BUG();
|
|
|
|
}
|
|
|
|
} else {
|
|
|
|
if (!(access & AFS_ACE_LOOKUP))
|
|
|
|
goto permission_denied;
|
|
|
|
if (mask & (MAY_EXEC | MAY_READ)) {
|
|
|
|
if (!(access & AFS_ACE_READ))
|
|
|
|
goto permission_denied;
|
|
|
|
} else if (mask & MAY_WRITE) {
|
|
|
|
if (!(access & AFS_ACE_WRITE))
|
|
|
|
goto permission_denied;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
key_put(key);
|
2007-04-27 00:59:35 +02:00
|
|
|
ret = generic_permission(inode, mask, NULL);
|
|
|
|
_leave(" = %d", ret);
|
|
|
|
return ret;
|
2007-04-27 00:57:07 +02:00
|
|
|
|
|
|
|
permission_denied:
|
2007-04-27 00:59:35 +02:00
|
|
|
ret = -EACCES;
|
|
|
|
error:
|
2007-04-27 00:57:07 +02:00
|
|
|
key_put(key);
|
2007-04-27 00:59:35 +02:00
|
|
|
_leave(" = %d", ret);
|
|
|
|
return ret;
|
2007-04-27 00:57:07 +02:00
|
|
|
}
|