[mirror_ubuntu-artful-kernel.git] / crypto / asymmetric_keys / pkcs7_key_type.c

/* Testing module to load key from trusted PKCS#7 message
 *
 * Copyright (C) 2014 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 Licence
 * as published by the Free Software Foundation; either version
 * 2 of the Licence, or (at your option) any later version.
 */

#define pr_fmt(fmt) "PKCS7key: "fmt
#include <linux/key.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/verification.h>
#include <linux/key-type.h>
#include <keys/user-type.h>

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("PKCS#7 testing key type");

static unsigned pkcs7_usage;
module_param_named(usage, pkcs7_usage, uint, S_IWUSR | S_IRUGO);
MODULE_PARM_DESC(pkcs7_usage,
		 "Usage to specify when verifying the PKCS#7 message");

/*
 * Retrieve the PKCS#7 message content.
 */
static int pkcs7_view_content(void *ctx, const void *data, size_t len,
			      size_t asn1hdrlen)
{
	struct key_preparsed_payload *prep = ctx;
	const void *saved_prep_data;
	size_t saved_prep_datalen;
	int ret;

	saved_prep_data = prep->data;
	saved_prep_datalen = prep->datalen;
	prep->data = data;
	prep->datalen = len;

	ret = user_preparse(prep);

	prep->data = saved_prep_data;
	prep->datalen = saved_prep_datalen;
	return ret;
}

/*
 * Preparse a PKCS#7 wrapped and validated data blob.
 */
static int pkcs7_preparse(struct key_preparsed_payload *prep)
{
	enum key_being_used_for usage = pkcs7_usage;

	if (usage >= NR__KEY_BEING_USED_FOR) {
		pr_err("Invalid usage type %d\n", usage);
		return -EINVAL;
	}

	return verify_pkcs7_signature(NULL, 0,
				      prep->data, prep->datalen,
				      (void *)1UL, usage,
				      pkcs7_view_content, prep);
}

/*
 * user defined keys take an arbitrary string as the description and an
 * arbitrary blob of data as the payload
 */
static struct key_type key_type_pkcs7 = {
	.name			= "pkcs7_test",
	.preparse		= pkcs7_preparse,
	.free_preparse		= user_free_preparse,
	.instantiate		= generic_key_instantiate,
	.revoke			= user_revoke,
	.destroy		= user_destroy,
	.describe		= user_describe,
	.read			= user_read,
};

/*
 * Module stuff
 */
static int __init pkcs7_key_init(void)
{
	return register_key_type(&key_type_pkcs7);
}

static void __exit pkcs7_key_cleanup(void)
{
	unregister_key_type(&key_type_pkcs7);
}

module_init(pkcs7_key_init);
module_exit(pkcs7_key_cleanup);
Commit	Line	Data
22d01afb DH	1	/* Testing module to load key from trusted PKCS#7 message
	2	*
	3	* Copyright (C) 2014 Red Hat, Inc. All Rights Reserved.
	4	* Written by David Howells (dhowells@redhat.com)
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public Licence
	8	* as published by the Free Software Foundation; either version
	9	* 2 of the Licence, or (at your option) any later version.
	10	*/
	11
	12	#define pr_fmt(fmt) "PKCS7key: "fmt
	13	#include <linux/key.h>
8f3438cc	14	#include <linux/err.h>
88775588	15	#include <linux/module.h>
e68503bd	16	#include <linux/verification.h>
22d01afb	17	#include <linux/key-type.h>
22d01afb	18	#include <keys/user-type.h>
22d01afb	19
772111ab DH	20	MODULE_LICENSE("GPL");
	21	MODULE_DESCRIPTION("PKCS#7 testing key type");
	22
99db4435 DH	23	static unsigned pkcs7_usage;
	24	module_param_named(usage, pkcs7_usage, uint, S_IWUSR \| S_IRUGO);
	25	MODULE_PARM_DESC(pkcs7_usage,
	26	"Usage to specify when verifying the PKCS#7 message");
	27
22d01afb	28	/*
e68503bd	29	* Retrieve the PKCS#7 message content.
22d01afb	30	*/
e68503bd DH	31	static int pkcs7_view_content(void ctx, const void data, size_t len,
e68503bd DH	32	size_t asn1hdrlen)
22d01afb	33	{
e68503bd DH	34	struct key_preparsed_payload *prep = ctx;
	35	const void *saved_prep_data;
	36	size_t saved_prep_datalen;
22d01afb DH	37	int ret;
22d01afb DH	38
22d01afb DH	39	saved_prep_data = prep->data;
22d01afb DH	40	saved_prep_datalen = prep->datalen;
22d01afb	41	prep->data = data;
e68503bd DH	42	prep->datalen = len;
e68503bd DH	43
1ca72c96	44	ret = user_preparse(prep);
e68503bd	45
22d01afb DH	46	prep->data = saved_prep_data;
22d01afb DH	47	prep->datalen = saved_prep_datalen;
22d01afb DH	48	return ret;
	49	}
	50
e68503bd DH	51	/*
	52	* Preparse a PKCS#7 wrapped and validated data blob.
	53	*/
	54	static int pkcs7_preparse(struct key_preparsed_payload *prep)
	55	{
	56	enum key_being_used_for usage = pkcs7_usage;
	57
	58	if (usage >= NR__KEY_BEING_USED_FOR) {
	59	pr_err("Invalid usage type %d\n", usage);
	60	return -EINVAL;
	61	}
	62
	63	return verify_pkcs7_signature(NULL, 0,
	64	prep->data, prep->datalen,
3c8f2278	65	(void *)1UL, usage,
e68503bd DH	66	pkcs7_view_content, prep);
	67	}
	68
22d01afb DH	69	/*
	70	* user defined keys take an arbitrary string as the description and an
	71	* arbitrary blob of data as the payload
	72	*/
63d2551e	73	static struct key_type key_type_pkcs7 = {
22d01afb	74	.name = "pkcs7_test",
1ca72c96 DH	75	.preparse = pkcs7_preparse,
	76	.free_preparse = user_free_preparse,
	77	.instantiate = generic_key_instantiate,
22d01afb DH	78	.revoke = user_revoke,
	79	.destroy = user_destroy,
	80	.describe = user_describe,
	81	.read = user_read,
	82	};
	83
	84	/*
	85	* Module stuff
	86	*/
	87	static int __init pkcs7_key_init(void)
	88	{
	89	return register_key_type(&key_type_pkcs7);
	90	}
	91
	92	static void __exit pkcs7_key_cleanup(void)
	93	{
	94	unregister_key_type(&key_type_pkcs7);
	95	}
	96
	97	module_init(pkcs7_key_init);
	98	module_exit(pkcs7_key_cleanup);