[linux-2.6-block.git] / security / integrity / ima / ima_init.c

/*
 * Copyright (C) 2005,2006,2007,2008 IBM Corporation
 *
 * Authors:
 * Reiner Sailer      <sailer@watson.ibm.com>
 * Leendert van Doorn <leendert@watson.ibm.com>
 * Mimi Zohar         <zohar@us.ibm.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, version 2 of the
 * License.
 *
 * File: ima_init.c
 *             initialization and cleanup functions
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/scatterlist.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <crypto/hash_info.h>
#include "ima.h"

/* name for boot aggregate entry */
static const char *boot_aggregate_name = "boot_aggregate";
int ima_used_chip;

/* Add the boot aggregate to the IMA measurement list and extend
 * the PCR register.
 *
 * Calculate the boot aggregate, a SHA1 over tpm registers 0-7,
 * assuming a TPM chip exists, and zeroes if the TPM chip does not
 * exist.  Add the boot aggregate measurement to the measurement
 * list and extend the PCR register.
 *
 * If a tpm chip does not exist, indicate the core root of trust is
 * not hardware based by invalidating the aggregate PCR value.
 * (The aggregate PCR value is invalidated by adding one value to
 * the measurement list and extending the aggregate PCR value with
 * a different value.) Violations add a zero entry to the measurement
 * list and extend the aggregate PCR value with ff...ff's.
 */
static void __init ima_add_boot_aggregate(void)
{
	static const char op[] = "add_boot_aggregate";
	const char *audit_cause = "ENOMEM";
	struct ima_template_entry *entry;
	struct integrity_iint_cache tmp_iint, *iint = &tmp_iint;
	int result = -ENOMEM;
	int violation = 0;
	struct {
		struct ima_digest_data hdr;
		char digest[TPM_DIGEST_SIZE];
	} hash;

	memset(iint, 0, sizeof(*iint));
	memset(&hash, 0, sizeof(hash));
	iint->ima_hash = &hash.hdr;
	iint->ima_hash->algo = HASH_ALGO_SHA1;
	iint->ima_hash->length = SHA1_DIGEST_SIZE;

	if (ima_used_chip) {
		result = ima_calc_boot_aggregate(&hash.hdr);
		if (result < 0) {
			audit_cause = "hashing_error";
			goto err_out;
		}
	}

	result = ima_alloc_init_template(iint, NULL, boot_aggregate_name,
					 NULL, 0, &entry);
	if (result < 0)
		return;

	result = ima_store_template(entry, violation, NULL,
				    boot_aggregate_name);
	if (result < 0)
		ima_free_template_entry(entry);
	return;
err_out:
	integrity_audit_msg(AUDIT_INTEGRITY_PCR, NULL, boot_aggregate_name, op,
			    audit_cause, result, 0);
}

int __init ima_init(void)
{
	u8 pcr_i[TPM_DIGEST_SIZE];
	int rc;

	ima_used_chip = 0;
	rc = tpm_pcr_read(TPM_ANY_NUM, 0, pcr_i);
	if (rc == 0)
		ima_used_chip = 1;

	if (!ima_used_chip)
		pr_info("No TPM chip found, activating TPM-bypass!\n");

	rc = ima_init_crypto();
	if (rc)
		return rc;
	rc = ima_init_template();
	if (rc != 0)
		return rc;

	ima_add_boot_aggregate();	/* boot aggregate must be first entry */
	ima_init_policy();

	return ima_fs_init();
}
Commit	Line	Data
3323eec9 MZ	1	/*
	2	* Copyright (C) 2005,2006,2007,2008 IBM Corporation
	3	*
	4	* Authors:
	5	* Reiner Sailer <sailer@watson.ibm.com>
	6	* Leendert van Doorn <leendert@watson.ibm.com>
	7	* Mimi Zohar <zohar@us.ibm.com>
	8	*
	9	* This program is free software; you can redistribute it and/or
	10	* modify it under the terms of the GNU General Public License as
	11	* published by the Free Software Foundation, version 2 of the
	12	* License.
	13	*
	14	* File: ima_init.c
	15	* initialization and cleanup functions
	16	*/
20ee451f JP	17
	18	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
	19
3323eec9 MZ	20	#include <linux/module.h>
3323eec9 MZ	21	#include <linux/scatterlist.h>
5a0e3ad6	22	#include <linux/slab.h>
3323eec9	23	#include <linux/err.h>
09ef5435	24	#include <crypto/hash_info.h>
3323eec9 MZ	25	#include "ima.h"
	26
	27	/* name for boot aggregate entry */
523979ad	28	static const char *boot_aggregate_name = "boot_aggregate";
3323eec9 MZ	29	int ima_used_chip;
	30
	31	/* Add the boot aggregate to the IMA measurement list and extend
	32	* the PCR register.
	33	*
	34	* Calculate the boot aggregate, a SHA1 over tpm registers 0-7,
	35	* assuming a TPM chip exists, and zeroes if the TPM chip does not
	36	* exist. Add the boot aggregate measurement to the measurement
	37	* list and extend the PCR register.
	38	*
	39	* If a tpm chip does not exist, indicate the core root of trust is
	40	* not hardware based by invalidating the aggregate PCR value.
	41	* (The aggregate PCR value is invalidated by adding one value to
	42	* the measurement list and extending the aggregate PCR value with
	43	* a different value.) Violations add a zero entry to the measurement
	44	* list and extend the aggregate PCR value with ff...ff's.
	45	*/
932995f0	46	static void __init ima_add_boot_aggregate(void)
3323eec9	47	{
52a13284 MZ	48	static const char op[] = "add_boot_aggregate";
52a13284 MZ	49	const char *audit_cause = "ENOMEM";
3323eec9	50	struct ima_template_entry *entry;
7bc5f447	51	struct integrity_iint_cache tmp_iint, *iint = &tmp_iint;
3323eec9	52	int result = -ENOMEM;
7bc5f447	53	int violation = 0;
09ef5435 DK	54	struct {
	55	struct ima_digest_data hdr;
	56	char digest[TPM_DIGEST_SIZE];
	57	} hash;
3323eec9	58
7bc5f447 RS	59	memset(iint, 0, sizeof(*iint));
	60	memset(&hash, 0, sizeof(hash));
	61	iint->ima_hash = &hash.hdr;
	62	iint->ima_hash->algo = HASH_ALGO_SHA1;
	63	iint->ima_hash->length = SHA1_DIGEST_SIZE;
3323eec9	64
3323eec9	65	if (ima_used_chip) {
09ef5435	66	result = ima_calc_boot_aggregate(&hash.hdr);
3323eec9 MZ	67	if (result < 0) {
3323eec9 MZ	68	audit_cause = "hashing_error";
3323eec9 MZ	69	goto err_out;
	70	}
	71	}
7bc5f447 RS	72
7bc5f447 RS	73	result = ima_alloc_init_template(iint, NULL, boot_aggregate_name,
bcbc9b0c	74	NULL, 0, &entry);
7bc5f447 RS	75	if (result < 0)
	76	return;
	77
9803d413 RS	78	result = ima_store_template(entry, violation, NULL,
9803d413 RS	79	boot_aggregate_name);
3323eec9	80	if (result < 0)
a7ed7c60	81	ima_free_template_entry(entry);
3323eec9 MZ	82	return;
	83	err_out:
	84	integrity_audit_msg(AUDIT_INTEGRITY_PCR, NULL, boot_aggregate_name, op,
	85	audit_cause, result, 0);
	86	}
	87
932995f0	88	int __init ima_init(void)
3323eec9	89	{
140d8022	90	u8 pcr_i[TPM_DIGEST_SIZE];
3323eec9 MZ	91	int rc;
	92
	93	ima_used_chip = 0;
	94	rc = tpm_pcr_read(TPM_ANY_NUM, 0, pcr_i);
	95	if (rc == 0)
	96	ima_used_chip = 1;
	97
	98	if (!ima_used_chip)
20ee451f	99	pr_info("No TPM chip found, activating TPM-bypass!\n");
3323eec9	100
76bb28f6 DK	101	rc = ima_init_crypto();
	102	if (rc)
	103	return rc;
adf53a77 RS	104	rc = ima_init_template();
	105	if (rc != 0)
	106	return rc;
	107
3323eec9 MZ	108	ima_add_boot_aggregate(); /* boot aggregate must be first entry */
3323eec9 MZ	109	ima_init_policy();
bab73937 MZ	110
	111	return ima_fs_init();
	112	}