[GitHub/mt8127/android_kernel_alcatel_ttab.git] / security / integrity / ima / ima_queue.c

/*
 * Copyright (C) 2005,2006,2007,2008 IBM Corporation
 *
 * Authors:
 * Serge Hallyn <serue@us.ibm.com>
 * Reiner Sailer <sailer@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_queue.c
 *       Implements queues that store template measurements and
 *       maintains aggregate over the stored measurements
 *       in the pre-configured TPM PCR (if available).
 *       The measurement list is append-only. No entry is
 *       ever removed or changed during the boot-cycle.
 */
#include <linux/module.h>
#include <linux/rculist.h>
#include <linux/slab.h>
#include "ima.h"

LIST_HEAD(ima_measurements);	/* list of all measurements */

/* key: inode (before secure-hashing a file) */
struct ima_h_table ima_htable = {
	.len = ATOMIC_LONG_INIT(0),
	.violations = ATOMIC_LONG_INIT(0),
	.queue[0 ... IMA_MEASURE_HTABLE_SIZE - 1] = HLIST_HEAD_INIT
};

/* mutex protects atomicity of extending measurement list
 * and extending the TPM PCR aggregate. Since tpm_extend can take
 * long (and the tpm driver uses a mutex), we can't use the spinlock.
 */
static DEFINE_MUTEX(ima_extend_list_mutex);

/* lookup up the digest value in the hash table, and return the entry */
static struct ima_queue_entry *ima_lookup_digest_entry(u8 *digest_value)
{
	struct ima_queue_entry *qe, *ret = NULL;
	unsigned int key;
	struct hlist_node *pos;
	int rc;

	key = ima_hash_key(digest_value);
	rcu_read_lock();
	hlist_for_each_entry_rcu(qe, pos, &ima_htable.queue[key], hnext) {
		rc = memcmp(qe->entry->digest, digest_value, IMA_DIGEST_SIZE);
		if (rc == 0) {
			ret = qe;
			break;
		}
	}
	rcu_read_unlock();
	return ret;
}

/* ima_add_template_entry helper function:
 * - Add template entry to measurement list and hash table.
 *
 * (Called with ima_extend_list_mutex held.)
 */
static int ima_add_digest_entry(struct ima_template_entry *entry)
{
	struct ima_queue_entry *qe;
	unsigned int key;

	qe = kmalloc(sizeof(*qe), GFP_KERNEL);
	if (qe == NULL) {
		pr_err("OUT OF MEMORY ERROR creating queue entry.\n");
		return -ENOMEM;
	}
	qe->entry = entry;

	INIT_LIST_HEAD(&qe->later);
	list_add_tail_rcu(&qe->later, &ima_measurements);

	atomic_long_inc(&ima_htable.len);
	key = ima_hash_key(entry->digest);
	hlist_add_head_rcu(&qe->hnext, &ima_htable.queue[key]);
	return 0;
}

static int ima_pcr_extend(const u8 *hash)
{
	int result = 0;

	if (!ima_used_chip)
		return result;

	result = tpm_pcr_extend(TPM_ANY_NUM, CONFIG_IMA_MEASURE_PCR_IDX, hash);
	if (result != 0)
		pr_err("Error Communicating to TPM chip\n");
	return result;
}

/* Add template entry to the measurement list and hash table,
 * and extend the pcr.
 */
int ima_add_template_entry(struct ima_template_entry *entry, int violation,
			   const char *op, struct inode *inode)
{
	u8 digest[IMA_DIGEST_SIZE];
	const char *audit_cause = "hash_added";
	int audit_info = 1;
	int result = 0;

	mutex_lock(&ima_extend_list_mutex);
	if (!violation) {
		memcpy(digest, entry->digest, sizeof digest);
		if (ima_lookup_digest_entry(digest)) {
			audit_cause = "hash_exists";
			goto out;
		}
	}

	result = ima_add_digest_entry(entry);
	if (result < 0) {
		audit_cause = "ENOMEM";
		audit_info = 0;
		goto out;
	}

	if (violation)		/* invalidate pcr */
		memset(digest, 0xff, sizeof digest);

	result = ima_pcr_extend(digest);
	if (result != 0) {
		audit_cause = "TPM error";
		audit_info = 0;
	}
out:
	mutex_unlock(&ima_extend_list_mutex);
	integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode,
			    entry->template.file_name,
			    op, audit_cause, result, audit_info);
	return result;
}
Commit	Line	Data
3323eec9 MZ	1	/*
	2	* Copyright (C) 2005,2006,2007,2008 IBM Corporation
	3	*
	4	* Authors:
	5	* Serge Hallyn <serue@us.ibm.com>
	6	* Reiner Sailer <sailer@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_queue.c
	15	* Implements queues that store template measurements and
	16	* maintains aggregate over the stored measurements
	17	* in the pre-configured TPM PCR (if available).
	18	* The measurement list is append-only. No entry is
	19	* ever removed or changed during the boot-cycle.
	20	*/
	21	#include <linux/module.h>
	22	#include <linux/rculist.h>
5a0e3ad6	23	#include <linux/slab.h>
3323eec9 MZ	24	#include "ima.h"
	25
	26	LIST_HEAD(ima_measurements); /* list of all measurements */
	27
	28	/* key: inode (before secure-hashing a file) */
	29	struct ima_h_table ima_htable = {
	30	.len = ATOMIC_LONG_INIT(0),
	31	.violations = ATOMIC_LONG_INIT(0),
	32	.queue[0 ... IMA_MEASURE_HTABLE_SIZE - 1] = HLIST_HEAD_INIT
	33	};
	34
	35	/* mutex protects atomicity of extending measurement list
	36	* and extending the TPM PCR aggregate. Since tpm_extend can take
	37	* long (and the tpm driver uses a mutex), we can't use the spinlock.
	38	*/
	39	static DEFINE_MUTEX(ima_extend_list_mutex);
	40
	41	/* lookup up the digest value in the hash table, and return the entry */
	42	static struct ima_queue_entry ima_lookup_digest_entry(u8 digest_value)
	43	{
	44	struct ima_queue_entry qe, ret = NULL;
	45	unsigned int key;
	46	struct hlist_node *pos;
	47	int rc;
	48
	49	key = ima_hash_key(digest_value);
	50	rcu_read_lock();
	51	hlist_for_each_entry_rcu(qe, pos, &ima_htable.queue[key], hnext) {
	52	rc = memcmp(qe->entry->digest, digest_value, IMA_DIGEST_SIZE);
	53	if (rc == 0) {
	54	ret = qe;
	55	break;
	56	}
	57	}
	58	rcu_read_unlock();
	59	return ret;
	60	}
	61
	62	/* ima_add_template_entry helper function:
	63	* - Add template entry to measurement list and hash table.
	64	*
	65	* (Called with ima_extend_list_mutex held.)
	66	*/
	67	static int ima_add_digest_entry(struct ima_template_entry *entry)
	68	{
	69	struct ima_queue_entry *qe;
	70	unsigned int key;
	71
	72	qe = kmalloc(sizeof(*qe), GFP_KERNEL);
	73	if (qe == NULL) {
	74	pr_err("OUT OF MEMORY ERROR creating queue entry.\n");
	75	return -ENOMEM;
	76	}
	77	qe->entry = entry;
	78
	79	INIT_LIST_HEAD(&qe->later);
	80	list_add_tail_rcu(&qe->later, &ima_measurements);
	81
	82	atomic_long_inc(&ima_htable.len);
	83	key = ima_hash_key(entry->digest);
	84	hlist_add_head_rcu(&qe->hnext, &ima_htable.queue[key]);
	85	return 0;
	86	}
	87
88	static int ima_pcr_extend(const u8 *hash)
89	{
90	int result = 0;
91
92	if (!ima_used_chip)
93	return result;
94
95	result = tpm_pcr_extend(TPM_ANY_NUM, CONFIG_IMA_MEASURE_PCR_IDX, hash);
96	if (result != 0)
97	pr_err("Error Communicating to TPM chip\n");
98	return result;
99	}
100
101	/* Add template entry to the measurement list and hash table,
102	* and extend the pcr.
103	*/
104	int ima_add_template_entry(struct ima_template_entry *entry, int violation,
105	const char op, struct inode inode)
106	{
107	u8 digest[IMA_DIGEST_SIZE];
108	const char *audit_cause = "hash_added";
109	int audit_info = 1;
110	int result = 0;
111
112	mutex_lock(&ima_extend_list_mutex);
113	if (!violation) {
114	memcpy(digest, entry->digest, sizeof digest);
115	if (ima_lookup_digest_entry(digest)) {
116	audit_cause = "hash_exists";
117	goto out;
118	}
119	}
120
121	result = ima_add_digest_entry(entry);
122	if (result < 0) {
123	audit_cause = "ENOMEM";
124	audit_info = 0;
125	goto out;
126	}
127
128	if (violation) /* invalidate pcr */
129	memset(digest, 0xff, sizeof digest);
130
131	result = ima_pcr_extend(digest);
132	if (result != 0) {
133	audit_cause = "TPM error";
134	audit_info = 0;
135	}
136	out:
137	mutex_unlock(&ima_extend_list_mutex);
79b854c5 MZ	138	integrity_audit_msg(AUDIT_INTEGRITY_PCR, inode,
79b854c5 MZ	139	entry->template.file_name,
3323eec9 MZ	140	op, audit_cause, result, audit_info);
	141	return result;
	142	}