linux-stable/security/keys/user_defined.c
Tim Schmielau cd354f1ae7 [PATCH] remove many unneeded #includes of sched.h
After Al Viro (finally) succeeded in removing the sched.h #include in module.h
recently, it makes sense again to remove other superfluous sched.h includes.
There are quite a lot of files which include it but don't actually need
anything defined in there.  Presumably these includes were once needed for
macros that used to live in sched.h, but moved to other header files in the
course of cleaning it up.

To ease the pain, this time I did not fiddle with any header files and only
removed #includes from .c-files, which tend to cause less trouble.

Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha,
arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig,
allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all
configs in arch/arm/configs on arm.  I also checked that no new warnings were
introduced by the patch (actually, some warnings are removed that were emitted
by unnecessarily included header files).

Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-14 08:09:54 -08:00

218 lines
5 KiB
C

/* user_defined.c: user defined key type
*
* Copyright (C) 2004 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/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/seq_file.h>
#include <linux/err.h>
#include <keys/user-type.h>
#include <asm/uaccess.h>
#include "internal.h"
/*
* user defined keys take an arbitrary string as the description and an
* arbitrary blob of data as the payload
*/
struct key_type key_type_user = {
.name = "user",
.instantiate = user_instantiate,
.update = user_update,
.match = user_match,
.revoke = user_revoke,
.destroy = user_destroy,
.describe = user_describe,
.read = user_read,
};
EXPORT_SYMBOL_GPL(key_type_user);
/*****************************************************************************/
/*
* instantiate a user defined key
*/
int user_instantiate(struct key *key, const void *data, size_t datalen)
{
struct user_key_payload *upayload;
int ret;
ret = -EINVAL;
if (datalen <= 0 || datalen > 32767 || !data)
goto error;
ret = key_payload_reserve(key, datalen);
if (ret < 0)
goto error;
ret = -ENOMEM;
upayload = kmalloc(sizeof(*upayload) + datalen, GFP_KERNEL);
if (!upayload)
goto error;
/* attach the data */
upayload->datalen = datalen;
memcpy(upayload->data, data, datalen);
rcu_assign_pointer(key->payload.data, upayload);
ret = 0;
error:
return ret;
} /* end user_instantiate() */
EXPORT_SYMBOL_GPL(user_instantiate);
/*****************************************************************************/
/*
* dispose of the old data from an updated user defined key
*/
static void user_update_rcu_disposal(struct rcu_head *rcu)
{
struct user_key_payload *upayload;
upayload = container_of(rcu, struct user_key_payload, rcu);
kfree(upayload);
} /* end user_update_rcu_disposal() */
/*****************************************************************************/
/*
* update a user defined key
* - the key's semaphore is write-locked
*/
int user_update(struct key *key, const void *data, size_t datalen)
{
struct user_key_payload *upayload, *zap;
int ret;
ret = -EINVAL;
if (datalen <= 0 || datalen > 32767 || !data)
goto error;
/* construct a replacement payload */
ret = -ENOMEM;
upayload = kmalloc(sizeof(*upayload) + datalen, GFP_KERNEL);
if (!upayload)
goto error;
upayload->datalen = datalen;
memcpy(upayload->data, data, datalen);
/* check the quota and attach the new data */
zap = upayload;
ret = key_payload_reserve(key, datalen);
if (ret == 0) {
/* attach the new data, displacing the old */
zap = key->payload.data;
rcu_assign_pointer(key->payload.data, upayload);
key->expiry = 0;
}
call_rcu(&zap->rcu, user_update_rcu_disposal);
error:
return ret;
} /* end user_update() */
EXPORT_SYMBOL_GPL(user_update);
/*****************************************************************************/
/*
* match users on their name
*/
int user_match(const struct key *key, const void *description)
{
return strcmp(key->description, description) == 0;
} /* end user_match() */
EXPORT_SYMBOL_GPL(user_match);
/*****************************************************************************/
/*
* dispose of the links from a revoked keyring
* - called with the key sem write-locked
*/
void user_revoke(struct key *key)
{
struct user_key_payload *upayload = key->payload.data;
/* clear the quota */
key_payload_reserve(key, 0);
if (upayload) {
rcu_assign_pointer(key->payload.data, NULL);
call_rcu(&upayload->rcu, user_update_rcu_disposal);
}
} /* end user_revoke() */
EXPORT_SYMBOL(user_revoke);
/*****************************************************************************/
/*
* dispose of the data dangling from the corpse of a user key
*/
void user_destroy(struct key *key)
{
struct user_key_payload *upayload = key->payload.data;
kfree(upayload);
} /* end user_destroy() */
EXPORT_SYMBOL_GPL(user_destroy);
/*****************************************************************************/
/*
* describe the user key
*/
void user_describe(const struct key *key, struct seq_file *m)
{
seq_puts(m, key->description);
seq_printf(m, ": %u", key->datalen);
} /* end user_describe() */
EXPORT_SYMBOL_GPL(user_describe);
/*****************************************************************************/
/*
* read the key data
* - the key's semaphore is read-locked
*/
long user_read(const struct key *key, char __user *buffer, size_t buflen)
{
struct user_key_payload *upayload;
long ret;
upayload = rcu_dereference(key->payload.data);
ret = upayload->datalen;
/* we can return the data as is */
if (buffer && buflen > 0) {
if (buflen > upayload->datalen)
buflen = upayload->datalen;
if (copy_to_user(buffer, upayload->data, buflen) != 0)
ret = -EFAULT;
}
return ret;
} /* end user_read() */
EXPORT_SYMBOL_GPL(user_read);