[mirror_ubuntu-artful-kernel.git] / security / integrity / ima / ima_fs.c

/*
 * Copyright (C) 2005,2006,2007,2008 IBM Corporation
 *
 * Authors:
 * Kylene Hall <kjhall@us.ibm.com>
 * Reiner Sailer <sailer@us.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_fs.c
 *	implemenents security file system for reporting
 *	current measurement list and IMA statistics
 */
#include <linux/fcntl.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/seq_file.h>
#include <linux/rculist.h>
#include <linux/rcupdate.h>
#include <linux/parser.h>

#include "ima.h"

static DEFINE_MUTEX(ima_write_mutex);

static int valid_policy = 1;
#define TMPBUFLEN 12
static ssize_t ima_show_htable_value(char __user *buf, size_t count,
				     loff_t *ppos, atomic_long_t *val)
{
	char tmpbuf[TMPBUFLEN];
	ssize_t len;

	len = scnprintf(tmpbuf, TMPBUFLEN, "%li\n", atomic_long_read(val));
	return simple_read_from_buffer(buf, count, ppos, tmpbuf, len);
}

static ssize_t ima_show_htable_violations(struct file *filp,
					  char __user *buf,
					  size_t count, loff_t *ppos)
{
	return ima_show_htable_value(buf, count, ppos, &ima_htable.violations);
}

static const struct file_operations ima_htable_violations_ops = {
	.read = ima_show_htable_violations,
	.llseek = generic_file_llseek,
};

static ssize_t ima_show_measurements_count(struct file *filp,
					   char __user *buf,
					   size_t count, loff_t *ppos)
{
	return ima_show_htable_value(buf, count, ppos, &ima_htable.len);

}

static const struct file_operations ima_measurements_count_ops = {
	.read = ima_show_measurements_count,
	.llseek = generic_file_llseek,
};

/* returns pointer to hlist_node */
static void *ima_measurements_start(struct seq_file *m, loff_t *pos)
{
	loff_t l = *pos;
	struct ima_queue_entry *qe;

	/* we need a lock since pos could point beyond last element */
	rcu_read_lock();
	list_for_each_entry_rcu(qe, &ima_measurements, later) {
		if (!l--) {
			rcu_read_unlock();
			return qe;
		}
	}
	rcu_read_unlock();
	return NULL;
}

static void *ima_measurements_next(struct seq_file *m, void *v, loff_t *pos)
{
	struct ima_queue_entry *qe = v;

	/* lock protects when reading beyond last element
	 * against concurrent list-extension
	 */
	rcu_read_lock();
	qe = list_entry_rcu(qe->later.next, struct ima_queue_entry, later);
	rcu_read_unlock();
	(*pos)++;

	return (&qe->later == &ima_measurements) ? NULL : qe;
}

static void ima_measurements_stop(struct seq_file *m, void *v)
{
}

void ima_putc(struct seq_file *m, void *data, int datalen)
{
	while (datalen--)
		seq_putc(m, *(char *)data++);
}

/* print format:
 *       32bit-le=pcr#
 *       char[20]=template digest
 *       32bit-le=template name size
 *       char[n]=template name
 *       [eventdata length]
 *       eventdata[n]=template specific data
 */
static int ima_measurements_show(struct seq_file *m, void *v)
{
	/* the list never shrinks, so we don't need a lock here */
	struct ima_queue_entry *qe = v;
	struct ima_template_entry *e;
	char *template_name;
	int namelen;
	u32 pcr = CONFIG_IMA_MEASURE_PCR_IDX;
	bool is_ima_template = false;
	int i;

	/* get entry */
	e = qe->entry;
	if (e == NULL)
		return -1;

	template_name = (e->template_desc->name[0] != '\0') ?
	    e->template_desc->name : e->template_desc->fmt;

	/*
	 * 1st: PCRIndex
	 * PCR used is always the same (config option) in
	 * little-endian format
	 */
	ima_putc(m, &pcr, sizeof(pcr));

	/* 2nd: template digest */
	ima_putc(m, e->digest, TPM_DIGEST_SIZE);

	/* 3rd: template name size */
	namelen = strlen(template_name);
	ima_putc(m, &namelen, sizeof(namelen));

	/* 4th:  template name */
	ima_putc(m, template_name, namelen);

	/* 5th:  template length (except for 'ima' template) */
	if (strcmp(template_name, IMA_TEMPLATE_IMA_NAME) == 0)
		is_ima_template = true;

	if (!is_ima_template)
		ima_putc(m, &e->template_data_len,
			 sizeof(e->template_data_len));

	/* 6th:  template specific data */
	for (i = 0; i < e->template_desc->num_fields; i++) {
		enum ima_show_type show = IMA_SHOW_BINARY;
		struct ima_template_field *field = e->template_desc->fields[i];

		if (is_ima_template && strcmp(field->field_id, "d") == 0)
			show = IMA_SHOW_BINARY_NO_FIELD_LEN;
		if (is_ima_template && strcmp(field->field_id, "n") == 0)
			show = IMA_SHOW_BINARY_OLD_STRING_FMT;
		field->field_show(m, show, &e->template_data[i]);
	}
	return 0;
}

static const struct seq_operations ima_measurments_seqops = {
	.start = ima_measurements_start,
	.next = ima_measurements_next,
	.stop = ima_measurements_stop,
	.show = ima_measurements_show
};

static int ima_measurements_open(struct inode *inode, struct file *file)
{
	return seq_open(file, &ima_measurments_seqops);
}

static const struct file_operations ima_measurements_ops = {
	.open = ima_measurements_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = seq_release,
};

void ima_print_digest(struct seq_file *m, u8 *digest, u32 size)
{
	u32 i;

	for (i = 0; i < size; i++)
		seq_printf(m, "%02x", *(digest + i));
}

/* print in ascii */
static int ima_ascii_measurements_show(struct seq_file *m, void *v)
{
	/* the list never shrinks, so we don't need a lock here */
	struct ima_queue_entry *qe = v;
	struct ima_template_entry *e;
	char *template_name;
	int i;

	/* get entry */
	e = qe->entry;
	if (e == NULL)
		return -1;

	template_name = (e->template_desc->name[0] != '\0') ?
	    e->template_desc->name : e->template_desc->fmt;

	/* 1st: PCR used (config option) */
	seq_printf(m, "%2d ", CONFIG_IMA_MEASURE_PCR_IDX);

	/* 2nd: SHA1 template hash */
	ima_print_digest(m, e->digest, TPM_DIGEST_SIZE);

	/* 3th:  template name */
	seq_printf(m, " %s", template_name);

	/* 4th:  template specific data */
	for (i = 0; i < e->template_desc->num_fields; i++) {
		seq_puts(m, " ");
		if (e->template_data[i].len == 0)
			continue;

		e->template_desc->fields[i]->field_show(m, IMA_SHOW_ASCII,
							&e->template_data[i]);
	}
	seq_puts(m, "\n");
	return 0;
}

static const struct seq_operations ima_ascii_measurements_seqops = {
	.start = ima_measurements_start,
	.next = ima_measurements_next,
	.stop = ima_measurements_stop,
	.show = ima_ascii_measurements_show
};

static int ima_ascii_measurements_open(struct inode *inode, struct file *file)
{
	return seq_open(file, &ima_ascii_measurements_seqops);
}

static const struct file_operations ima_ascii_measurements_ops = {
	.open = ima_ascii_measurements_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = seq_release,
};

static ssize_t ima_write_policy(struct file *file, const char __user *buf,
				size_t datalen, loff_t *ppos)
{
	char *data = NULL;
	ssize_t result;
	int res;

	res = mutex_lock_interruptible(&ima_write_mutex);
	if (res)
		return res;

	if (datalen >= PAGE_SIZE)
		datalen = PAGE_SIZE - 1;

	/* No partial writes. */
	result = -EINVAL;
	if (*ppos != 0)
		goto out;

	result = -ENOMEM;
	data = kmalloc(datalen + 1, GFP_KERNEL);
	if (!data)
		goto out;

	*(data + datalen) = '\0';

	result = -EFAULT;
	if (copy_from_user(data, buf, datalen))
		goto out;

	result = ima_parse_add_rule(data);
out:
	if (result < 0)
		valid_policy = 0;
	kfree(data);
	mutex_unlock(&ima_write_mutex);

	return result;
}

static struct dentry *ima_dir;
static struct dentry *binary_runtime_measurements;
static struct dentry *ascii_runtime_measurements;
static struct dentry *runtime_measurements_count;
static struct dentry *violations;
static struct dentry *ima_policy;

enum ima_fs_flags {
	IMA_FS_BUSY,
};

static unsigned long ima_fs_flags;

/*
 * ima_open_policy: sequentialize access to the policy file
 */
static int ima_open_policy(struct inode *inode, struct file *filp)
{
	/* No point in being allowed to open it if you aren't going to write */
	if (!(filp->f_flags & O_WRONLY))
		return -EACCES;
	if (test_and_set_bit(IMA_FS_BUSY, &ima_fs_flags))
		return -EBUSY;
	return 0;
}

/*
 * ima_release_policy - start using the new measure policy rules.
 *
 * Initially, ima_measure points to the default policy rules, now
 * point to the new policy rules, and remove the securityfs policy file,
 * assuming a valid policy.
 */
static int ima_release_policy(struct inode *inode, struct file *file)
{
	const char *cause = valid_policy ? "completed" : "failed";

	pr_info("IMA: policy update %s\n", cause);
	integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL, NULL,
			    "policy_update", cause, !valid_policy, 0);

	if (!valid_policy) {
		ima_delete_rules();
		valid_policy = 1;
		clear_bit(IMA_FS_BUSY, &ima_fs_flags);
		return 0;
	}
	ima_update_policy();
#ifndef	CONFIG_IMA_WRITE_POLICY
	securityfs_remove(ima_policy);
	ima_policy = NULL;
#else
	clear_bit(IMA_FS_BUSY, &ima_fs_flags);
#endif
	return 0;
}

static const struct file_operations ima_measure_policy_ops = {
	.open = ima_open_policy,
	.write = ima_write_policy,
	.release = ima_release_policy,
	.llseek = generic_file_llseek,
};

int __init ima_fs_init(void)
{
	ima_dir = securityfs_create_dir("ima", NULL);
	if (IS_ERR(ima_dir))
		return -1;

	binary_runtime_measurements =
	    securityfs_create_file("binary_runtime_measurements",
				   S_IRUSR | S_IRGRP, ima_dir, NULL,
				   &ima_measurements_ops);
	if (IS_ERR(binary_runtime_measurements))
		goto out;

	ascii_runtime_measurements =
	    securityfs_create_file("ascii_runtime_measurements",
				   S_IRUSR | S_IRGRP, ima_dir, NULL,
				   &ima_ascii_measurements_ops);
	if (IS_ERR(ascii_runtime_measurements))
		goto out;

	runtime_measurements_count =
	    securityfs_create_file("runtime_measurements_count",
				   S_IRUSR | S_IRGRP, ima_dir, NULL,
				   &ima_measurements_count_ops);
	if (IS_ERR(runtime_measurements_count))
		goto out;

	violations =
	    securityfs_create_file("violations", S_IRUSR | S_IRGRP,
				   ima_dir, NULL, &ima_htable_violations_ops);
	if (IS_ERR(violations))
		goto out;

	ima_policy = securityfs_create_file("policy",
					    S_IWUSR,
					    ima_dir, NULL,
					    &ima_measure_policy_ops);
	if (IS_ERR(ima_policy))
		goto out;

	return 0;
out:
	securityfs_remove(violations);
	securityfs_remove(runtime_measurements_count);
	securityfs_remove(ascii_runtime_measurements);
	securityfs_remove(binary_runtime_measurements);
	securityfs_remove(ima_dir);
	securityfs_remove(ima_policy);
	return -1;
}
Commit	Line	Data
bab73937 MZ	1	/*
	2	* Copyright (C) 2005,2006,2007,2008 IBM Corporation
	3	*
	4	* Authors:
	5	* Kylene Hall <kjhall@us.ibm.com>
	6	* Reiner Sailer <sailer@us.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_fs.c
	15	* implemenents security file system for reporting
	16	* current measurement list and IMA statistics
	17	*/
f850a7c0	18	#include <linux/fcntl.h>
5a0e3ad6	19	#include <linux/slab.h>
bab73937 MZ	20	#include <linux/module.h>
	21	#include <linux/seq_file.h>
	22	#include <linux/rculist.h>
	23	#include <linux/rcupdate.h>
4af4662f	24	#include <linux/parser.h>
bab73937 MZ	25
	26	#include "ima.h"
	27
38d859f9 PM	28	static DEFINE_MUTEX(ima_write_mutex);
38d859f9 PM	29
4af4662f	30	static int valid_policy = 1;
bab73937 MZ	31	#define TMPBUFLEN 12
	32	static ssize_t ima_show_htable_value(char __user *buf, size_t count,
	33	loff_t ppos, atomic_long_t val)
	34	{
	35	char tmpbuf[TMPBUFLEN];
	36	ssize_t len;
	37
	38	len = scnprintf(tmpbuf, TMPBUFLEN, "%li\n", atomic_long_read(val));
	39	return simple_read_from_buffer(buf, count, ppos, tmpbuf, len);
	40	}
	41
	42	static ssize_t ima_show_htable_violations(struct file *filp,
	43	char __user *buf,
	44	size_t count, loff_t *ppos)
	45	{
	46	return ima_show_htable_value(buf, count, ppos, &ima_htable.violations);
	47	}
	48
828c0950	49	static const struct file_operations ima_htable_violations_ops = {
cdcd90f9 AB	50	.read = ima_show_htable_violations,
cdcd90f9 AB	51	.llseek = generic_file_llseek,
bab73937 MZ	52	};
	53
	54	static ssize_t ima_show_measurements_count(struct file *filp,
	55	char __user *buf,
	56	size_t count, loff_t *ppos)
	57	{
	58	return ima_show_htable_value(buf, count, ppos, &ima_htable.len);
	59
	60	}
	61
828c0950	62	static const struct file_operations ima_measurements_count_ops = {
cdcd90f9 AB	63	.read = ima_show_measurements_count,
cdcd90f9 AB	64	.llseek = generic_file_llseek,
bab73937 MZ	65	};
	66
	67	/* returns pointer to hlist_node */
	68	static void ima_measurements_start(struct seq_file m, loff_t *pos)
	69	{
	70	loff_t l = *pos;
	71	struct ima_queue_entry *qe;
	72
	73	/* we need a lock since pos could point beyond last element */
	74	rcu_read_lock();
	75	list_for_each_entry_rcu(qe, &ima_measurements, later) {
	76	if (!l--) {
	77	rcu_read_unlock();
	78	return qe;
	79	}
	80	}
	81	rcu_read_unlock();
	82	return NULL;
	83	}
	84
	85	static void ima_measurements_next(struct seq_file m, void v, loff_t pos)
	86	{
	87	struct ima_queue_entry *qe = v;
	88
	89	/* lock protects when reading beyond last element
	90	* against concurrent list-extension
	91	*/
	92	rcu_read_lock();
089bc8e9	93	qe = list_entry_rcu(qe->later.next, struct ima_queue_entry, later);
bab73937 MZ	94	rcu_read_unlock();
	95	(*pos)++;
	96
	97	return (&qe->later == &ima_measurements) ? NULL : qe;
	98	}
	99
	100	static void ima_measurements_stop(struct seq_file m, void v)
	101	{
	102	}
	103
3ce1217d	104	void ima_putc(struct seq_file m, void data, int datalen)
bab73937 MZ	105	{
	106	while (datalen--)
	107	seq_putc(m, (char )data++);
	108	}
	109
	110	/* print format:
	111	* 32bit-le=pcr#
	112	* char[20]=template digest
	113	* 32bit-le=template name size
	114	* char[n]=template name
a71dc65d	115	* [eventdata length]
bab73937 MZ	116	* eventdata[n]=template specific data
	117	*/
	118	static int ima_measurements_show(struct seq_file m, void v)
	119	{
	120	/* the list never shrinks, so we don't need a lock here */
	121	struct ima_queue_entry *qe = v;
	122	struct ima_template_entry *e;
7dbdb420	123	char *template_name;
bab73937 MZ	124	int namelen;
bab73937 MZ	125	u32 pcr = CONFIG_IMA_MEASURE_PCR_IDX;
3e8e5503	126	bool is_ima_template = false;
a71dc65d	127	int i;
bab73937 MZ	128
	129	/* get entry */
	130	e = qe->entry;
	131	if (e == NULL)
	132	return -1;
	133
7dbdb420 RS	134	template_name = (e->template_desc->name[0] != '\0') ?
	135	e->template_desc->name : e->template_desc->fmt;
	136
bab73937 MZ	137	/*
	138	* 1st: PCRIndex
	139	* PCR used is always the same (config option) in
	140	* little-endian format
	141	*/
2bb930ab	142	ima_putc(m, &pcr, sizeof(pcr));
bab73937 MZ	143
bab73937 MZ	144	/* 2nd: template digest */
140d8022	145	ima_putc(m, e->digest, TPM_DIGEST_SIZE);
bab73937 MZ	146
bab73937 MZ	147	/* 3rd: template name size */
7dbdb420	148	namelen = strlen(template_name);
2bb930ab	149	ima_putc(m, &namelen, sizeof(namelen));
bab73937 MZ	150
bab73937 MZ	151	/* 4th: template name */
7dbdb420	152	ima_putc(m, template_name, namelen);
a71dc65d RS	153
a71dc65d RS	154	/* 5th: template length (except for 'ima' template) */
7dbdb420	155	if (strcmp(template_name, IMA_TEMPLATE_IMA_NAME) == 0)
3e8e5503 RS	156	is_ima_template = true;
	157
	158	if (!is_ima_template)
a71dc65d RS	159	ima_putc(m, &e->template_data_len,
a71dc65d RS	160	sizeof(e->template_data_len));
bab73937	161
a71dc65d RS	162	/* 6th: template specific data */
a71dc65d RS	163	for (i = 0; i < e->template_desc->num_fields; i++) {
3e8e5503 RS	164	enum ima_show_type show = IMA_SHOW_BINARY;
	165	struct ima_template_field *field = e->template_desc->fields[i];
	166
	167	if (is_ima_template && strcmp(field->field_id, "d") == 0)
	168	show = IMA_SHOW_BINARY_NO_FIELD_LEN;
c019e307 RS	169	if (is_ima_template && strcmp(field->field_id, "n") == 0)
c019e307 RS	170	show = IMA_SHOW_BINARY_OLD_STRING_FMT;
3e8e5503	171	field->field_show(m, show, &e->template_data[i]);
a71dc65d	172	}
bab73937 MZ	173	return 0;
	174	}
	175
88e9d34c	176	static const struct seq_operations ima_measurments_seqops = {
bab73937 MZ	177	.start = ima_measurements_start,
	178	.next = ima_measurements_next,
	179	.stop = ima_measurements_stop,
	180	.show = ima_measurements_show
	181	};
	182
	183	static int ima_measurements_open(struct inode inode, struct file file)
	184	{
	185	return seq_open(file, &ima_measurments_seqops);
	186	}
	187
828c0950	188	static const struct file_operations ima_measurements_ops = {
bab73937 MZ	189	.open = ima_measurements_open,
	190	.read = seq_read,
	191	.llseek = seq_lseek,
	192	.release = seq_release,
	193	};
	194
45b26133	195	void ima_print_digest(struct seq_file m, u8 digest, u32 size)
bab73937	196	{
45b26133	197	u32 i;
bab73937	198
140d8022	199	for (i = 0; i < size; i++)
bab73937 MZ	200	seq_printf(m, "%02x", *(digest + i));
	201	}
	202
bab73937 MZ	203	/* print in ascii */
	204	static int ima_ascii_measurements_show(struct seq_file m, void v)
	205	{
	206	/* the list never shrinks, so we don't need a lock here */
	207	struct ima_queue_entry *qe = v;
	208	struct ima_template_entry *e;
7dbdb420	209	char *template_name;
a71dc65d	210	int i;
bab73937 MZ	211
	212	/* get entry */
	213	e = qe->entry;
	214	if (e == NULL)
	215	return -1;
	216
7dbdb420 RS	217	template_name = (e->template_desc->name[0] != '\0') ?
	218	e->template_desc->name : e->template_desc->fmt;
	219
bab73937 MZ	220	/* 1st: PCR used (config option) */
	221	seq_printf(m, "%2d ", CONFIG_IMA_MEASURE_PCR_IDX);
	222
	223	/* 2nd: SHA1 template hash */
140d8022	224	ima_print_digest(m, e->digest, TPM_DIGEST_SIZE);
bab73937 MZ	225
bab73937 MZ	226	/* 3th: template name */
7dbdb420	227	seq_printf(m, " %s", template_name);
bab73937 MZ	228
bab73937 MZ	229	/* 4th: template specific data */
a71dc65d RS	230	for (i = 0; i < e->template_desc->num_fields; i++) {
	231	seq_puts(m, " ");
	232	if (e->template_data[i].len == 0)
	233	continue;
	234
	235	e->template_desc->fields[i]->field_show(m, IMA_SHOW_ASCII,
	236	&e->template_data[i]);
	237	}
	238	seq_puts(m, "\n");
bab73937 MZ	239	return 0;
	240	}
	241
88e9d34c	242	static const struct seq_operations ima_ascii_measurements_seqops = {
bab73937 MZ	243	.start = ima_measurements_start,
	244	.next = ima_measurements_next,
	245	.stop = ima_measurements_stop,
	246	.show = ima_ascii_measurements_show
	247	};
	248
	249	static int ima_ascii_measurements_open(struct inode inode, struct file file)
	250	{
	251	return seq_open(file, &ima_ascii_measurements_seqops);
	252	}
	253
828c0950	254	static const struct file_operations ima_ascii_measurements_ops = {
bab73937 MZ	255	.open = ima_ascii_measurements_open,
	256	.read = seq_read,
	257	.llseek = seq_lseek,
	258	.release = seq_release,
	259	};
	260
4af4662f MZ	261	static ssize_t ima_write_policy(struct file file, const char __user buf,
	262	size_t datalen, loff_t *ppos)
	263	{
6ccd0456 EP	264	char *data = NULL;
6ccd0456 EP	265	ssize_t result;
38d859f9 PM	266	int res;
	267
	268	res = mutex_lock_interruptible(&ima_write_mutex);
	269	if (res)
	270	return res;
4af4662f MZ	271
4af4662f MZ	272	if (datalen >= PAGE_SIZE)
6ccd0456 EP	273	datalen = PAGE_SIZE - 1;
	274
	275	/* No partial writes. */
	276	result = -EINVAL;
	277	if (*ppos != 0)
	278	goto out;
	279
	280	result = -ENOMEM;
4af4662f MZ	281	data = kmalloc(datalen + 1, GFP_KERNEL);
4af4662f MZ	282	if (!data)
6ccd0456	283	goto out;
4af4662f	284
4af4662f	285	*(data + datalen) = '\0';
4af4662f	286
6ccd0456 EP	287	result = -EFAULT;
	288	if (copy_from_user(data, buf, datalen))
	289	goto out;
	290
	291	result = ima_parse_add_rule(data);
	292	out:
	293	if (result < 0)
	294	valid_policy = 0;
4af4662f	295	kfree(data);
38d859f9 PM	296	mutex_unlock(&ima_write_mutex);
38d859f9 PM	297
6ccd0456	298	return result;
4af4662f MZ	299	}
4af4662f MZ	300
bab73937 MZ	301	static struct dentry *ima_dir;
	302	static struct dentry *binary_runtime_measurements;
	303	static struct dentry *ascii_runtime_measurements;
	304	static struct dentry *runtime_measurements_count;
	305	static struct dentry *violations;
4af4662f MZ	306	static struct dentry *ima_policy;
4af4662f MZ	307
0716abbb DK	308	enum ima_fs_flags {
	309	IMA_FS_BUSY,
	310	};
	311
	312	static unsigned long ima_fs_flags;
	313
f4bd857b MZ	314	/*
	315	* ima_open_policy: sequentialize access to the policy file
	316	*/
2bb930ab	317	static int ima_open_policy(struct inode inode, struct file filp)
f4bd857b	318	{
f850a7c0 EP	319	/* No point in being allowed to open it if you aren't going to write */
	320	if (!(filp->f_flags & O_WRONLY))
	321	return -EACCES;
0716abbb DK	322	if (test_and_set_bit(IMA_FS_BUSY, &ima_fs_flags))
	323	return -EBUSY;
	324	return 0;
f4bd857b MZ	325	}
f4bd857b MZ	326
4af4662f MZ	327	/*
	328	* ima_release_policy - start using the new measure policy rules.
	329	*
	330	* Initially, ima_measure points to the default policy rules, now
f4bd857b MZ	331	* point to the new policy rules, and remove the securityfs policy file,
f4bd857b MZ	332	* assuming a valid policy.
4af4662f MZ	333	*/
	334	static int ima_release_policy(struct inode inode, struct file file)
	335	{
0716abbb DK	336	const char *cause = valid_policy ? "completed" : "failed";
	337
	338	pr_info("IMA: policy update %s\n", cause);
	339	integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL, NULL,
	340	"policy_update", cause, !valid_policy, 0);
	341
4af4662f MZ	342	if (!valid_policy) {
4af4662f MZ	343	ima_delete_rules();
f4bd857b	344	valid_policy = 1;
0716abbb	345	clear_bit(IMA_FS_BUSY, &ima_fs_flags);
4af4662f MZ	346	return 0;
	347	}
	348	ima_update_policy();
38d859f9	349	#ifndef CONFIG_IMA_WRITE_POLICY
4af4662f MZ	350	securityfs_remove(ima_policy);
4af4662f MZ	351	ima_policy = NULL;
38d859f9 PM	352	#else
	353	clear_bit(IMA_FS_BUSY, &ima_fs_flags);
	354	#endif
4af4662f MZ	355	return 0;
	356	}
	357
828c0950	358	static const struct file_operations ima_measure_policy_ops = {
f4bd857b	359	.open = ima_open_policy,
4af4662f	360	.write = ima_write_policy,
cdcd90f9 AB	361	.release = ima_release_policy,
cdcd90f9 AB	362	.llseek = generic_file_llseek,
4af4662f	363	};
bab73937	364
932995f0	365	int __init ima_fs_init(void)
bab73937 MZ	366	{
	367	ima_dir = securityfs_create_dir("ima", NULL);
	368	if (IS_ERR(ima_dir))
	369	return -1;
	370
	371	binary_runtime_measurements =
	372	securityfs_create_file("binary_runtime_measurements",
	373	S_IRUSR \| S_IRGRP, ima_dir, NULL,
	374	&ima_measurements_ops);
	375	if (IS_ERR(binary_runtime_measurements))
	376	goto out;
	377
	378	ascii_runtime_measurements =
	379	securityfs_create_file("ascii_runtime_measurements",
	380	S_IRUSR \| S_IRGRP, ima_dir, NULL,
	381	&ima_ascii_measurements_ops);
	382	if (IS_ERR(ascii_runtime_measurements))
	383	goto out;
	384
	385	runtime_measurements_count =
	386	securityfs_create_file("runtime_measurements_count",
	387	S_IRUSR \| S_IRGRP, ima_dir, NULL,
	388	&ima_measurements_count_ops);
	389	if (IS_ERR(runtime_measurements_count))
	390	goto out;
	391
	392	violations =
	393	securityfs_create_file("violations", S_IRUSR \| S_IRGRP,
	394	ima_dir, NULL, &ima_htable_violations_ops);
	395	if (IS_ERR(violations))
	396	goto out;
	397
4af4662f	398	ima_policy = securityfs_create_file("policy",
f850a7c0	399	S_IWUSR,
4af4662f MZ	400	ima_dir, NULL,
	401	&ima_measure_policy_ops);
	402	if (IS_ERR(ima_policy))
	403	goto out;
bab73937	404
4af4662f	405	return 0;
bab73937	406	out:
0ea4f8ae	407	securityfs_remove(violations);
bab73937 MZ	408	securityfs_remove(runtime_measurements_count);
	409	securityfs_remove(ascii_runtime_measurements);
	410	securityfs_remove(binary_runtime_measurements);
	411	securityfs_remove(ima_dir);
4af4662f	412	securityfs_remove(ima_policy);
bab73937 MZ	413	return -1;
bab73937 MZ	414	}