[mirror_ubuntu-bionic-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");
MODULE_AUTHOR("Red Hat, Inc.");

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");
772111ab DH	21	MODULE_DESCRIPTION("PKCS#7 testing key type");
1e684d38	22	MODULE_AUTHOR("Red Hat, Inc.");
772111ab	23
99db4435 DH	24	static unsigned pkcs7_usage;
	25	module_param_named(usage, pkcs7_usage, uint, S_IWUSR \| S_IRUGO);
	26	MODULE_PARM_DESC(pkcs7_usage,
	27	"Usage to specify when verifying the PKCS#7 message");
	28
22d01afb	29	/*
e68503bd	30	* Retrieve the PKCS#7 message content.
22d01afb	31	*/
e68503bd DH	32	static int pkcs7_view_content(void ctx, const void data, size_t len,
e68503bd DH	33	size_t asn1hdrlen)
22d01afb	34	{
e68503bd DH	35	struct key_preparsed_payload *prep = ctx;
	36	const void *saved_prep_data;
	37	size_t saved_prep_datalen;
22d01afb DH	38	int ret;
22d01afb DH	39
22d01afb DH	40	saved_prep_data = prep->data;
22d01afb DH	41	saved_prep_datalen = prep->datalen;
22d01afb	42	prep->data = data;
e68503bd DH	43	prep->datalen = len;
e68503bd DH	44
1ca72c96	45	ret = user_preparse(prep);
e68503bd	46
22d01afb DH	47	prep->data = saved_prep_data;
22d01afb DH	48	prep->datalen = saved_prep_datalen;
22d01afb DH	49	return ret;
	50	}
	51
e68503bd DH	52	/*
	53	* Preparse a PKCS#7 wrapped and validated data blob.
	54	*/
	55	static int pkcs7_preparse(struct key_preparsed_payload *prep)
	56	{
	57	enum key_being_used_for usage = pkcs7_usage;
	58
	59	if (usage >= NR__KEY_BEING_USED_FOR) {
	60	pr_err("Invalid usage type %d\n", usage);
	61	return -EINVAL;
	62	}
	63
	64	return verify_pkcs7_signature(NULL, 0,
	65	prep->data, prep->datalen,
3c8f2278	66	(void *)1UL, usage,
e68503bd DH	67	pkcs7_view_content, prep);
	68	}
	69
22d01afb DH	70	/*
	71	* user defined keys take an arbitrary string as the description and an
	72	* arbitrary blob of data as the payload
	73	*/
63d2551e	74	static struct key_type key_type_pkcs7 = {
22d01afb	75	.name = "pkcs7_test",
1ca72c96 DH	76	.preparse = pkcs7_preparse,
	77	.free_preparse = user_free_preparse,
	78	.instantiate = generic_key_instantiate,
22d01afb DH	79	.revoke = user_revoke,
	80	.destroy = user_destroy,
	81	.describe = user_describe,
	82	.read = user_read,
	83	};
	84
	85	/*
	86	* Module stuff
	87	*/
	88	static int __init pkcs7_key_init(void)
	89	{
	90	return register_key_type(&key_type_pkcs7);
	91	}
	92
	93	static void __exit pkcs7_key_cleanup(void)
	94	{
	95	unregister_key_type(&key_type_pkcs7);
	96	}
	97
	98	module_init(pkcs7_key_init);
	99	module_exit(pkcs7_key_cleanup);