[mirror_ubuntu-bionic-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 <linux/vmalloc.h>

#include "ima.h"

static DEFINE_MUTEX(ima_write_mutex);

bool ima_canonical_fmt;
static int __init default_canonical_fmt_setup(char *str)
{
#ifdef __BIG_ENDIAN
	ima_canonical_fmt = true;
#endif
	return 1;
}
__setup("ima_canonical_fmt", default_canonical_fmt_setup);

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
 */
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;
	u32 pcr, namelen, template_data_len; /* temporary fields */
	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 defaults to the same (config option) in
	 * little-endian format, unless set in policy
	 */
	pcr = !ima_canonical_fmt ? e->pcr : cpu_to_le32(e->pcr);
	ima_putc(m, &pcr, sizeof(e->pcr));

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

	/* 3rd: template name size */
	namelen = !ima_canonical_fmt ? strlen(template_name) :
		cpu_to_le32(strlen(template_name));
	ima_putc(m, &namelen, sizeof(namelen));

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

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

	if (!is_ima_template) {
		template_data_len = !ima_canonical_fmt ? e->template_data_len :
			cpu_to_le32(e->template_data_len);
		ima_putc(m, &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 ", e->pcr);

	/* 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_read_policy(char *path)
{
	void *data;
	char *datap;
	loff_t size;
	int rc, pathlen = strlen(path);

	char *p;

	/* remove \n */
	datap = path;
	strsep(&datap, "\n");

	rc = kernel_read_file_from_path(path, &data, &size, 0, READING_POLICY);
	if (rc < 0) {
		pr_warn("Unable to open file: %s (%d)", path, rc);
		return rc;
	}

	datap = data;
	while (size > 0 && (p = strsep(&datap, "\n"))) {
		pr_debug("rule: %s\n", p);
		rc = ima_parse_add_rule(p);
		if (rc < 0)
			break;
		size -= rc;
	}

	vfree(data);
	if (rc < 0)
		return rc;
	else if (size)
		return -EINVAL;
	else
		return pathlen;
}

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

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

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

	data = memdup_user_nul(buf, datalen);
	if (IS_ERR(data)) {
		result = PTR_ERR(data);
		goto out;
	}

	result = mutex_lock_interruptible(&ima_write_mutex);
	if (result < 0)
		goto out_free;

	if (data[0] == '/') {
		result = ima_read_policy(data);
	} else if (ima_appraise & IMA_APPRAISE_POLICY) {
		pr_err("IMA: signed policy file (specified as an absolute pathname) required\n");
		integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL, NULL,
				    "policy_update", "signed policy required",
				    1, 0);
		if (ima_appraise & IMA_APPRAISE_ENFORCE)
			result = -EACCES;
	} else {
		result = ima_parse_add_rule(data);
	}
	mutex_unlock(&ima_write_mutex);
out_free:
	kfree(data);
out:
	if (result < 0)
		valid_policy = 0;

	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;

#ifdef	CONFIG_IMA_READ_POLICY
static const struct seq_operations ima_policy_seqops = {
		.start = ima_policy_start,
		.next = ima_policy_next,
		.stop = ima_policy_stop,
		.show = ima_policy_show,
};
#endif

/*
 * ima_open_policy: sequentialize access to the policy file
 */
static int ima_open_policy(struct inode *inode, struct file *filp)
{
	if (!(filp->f_flags & O_WRONLY)) {
#ifndef	CONFIG_IMA_READ_POLICY
		return -EACCES;
#else
		if ((filp->f_flags & O_ACCMODE) != O_RDONLY)
			return -EACCES;
		if (!capable(CAP_SYS_ADMIN))
			return -EPERM;
		return seq_open(filp, &ima_policy_seqops);
#endif
	}
	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";

	if ((file->f_flags & O_ACCMODE) == O_RDONLY)
		return seq_release(inode, file);

	if (valid_policy && ima_check_policy() < 0) {
		cause = "failed";
		valid_policy = 0;
	}

	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();
#if !defined(CONFIG_IMA_WRITE_POLICY) && !defined(CONFIG_IMA_READ_POLICY)
	securityfs_remove(ima_policy);
	ima_policy = NULL;
#elif defined(CONFIG_IMA_WRITE_POLICY)
	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,
	.read = seq_read,
	.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", POLICY_FILE_FLAGS,
					    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>
7429b092	25	#include <linux/vmalloc.h>
bab73937 MZ	26
	27	#include "ima.h"
	28
38d859f9 PM	29	static DEFINE_MUTEX(ima_write_mutex);
38d859f9 PM	30
d68a6fe9 MZ	31	bool ima_canonical_fmt;
	32	static int __init default_canonical_fmt_setup(char *str)
	33	{
	34	#ifdef __BIG_ENDIAN
39adb925	35	ima_canonical_fmt = true;
d68a6fe9 MZ	36	#endif
	37	return 1;
	38	}
	39	__setup("ima_canonical_fmt", default_canonical_fmt_setup);
	40
4af4662f	41	static int valid_policy = 1;
bab73937 MZ	42	#define TMPBUFLEN 12
	43	static ssize_t ima_show_htable_value(char __user *buf, size_t count,
	44	loff_t ppos, atomic_long_t val)
	45	{
	46	char tmpbuf[TMPBUFLEN];
	47	ssize_t len;
	48
	49	len = scnprintf(tmpbuf, TMPBUFLEN, "%li\n", atomic_long_read(val));
	50	return simple_read_from_buffer(buf, count, ppos, tmpbuf, len);
	51	}
	52
	53	static ssize_t ima_show_htable_violations(struct file *filp,
	54	char __user *buf,
	55	size_t count, loff_t *ppos)
	56	{
	57	return ima_show_htable_value(buf, count, ppos, &ima_htable.violations);
	58	}
	59
828c0950	60	static const struct file_operations ima_htable_violations_ops = {
cdcd90f9 AB	61	.read = ima_show_htable_violations,
cdcd90f9 AB	62	.llseek = generic_file_llseek,
bab73937 MZ	63	};
	64
	65	static ssize_t ima_show_measurements_count(struct file *filp,
	66	char __user *buf,
	67	size_t count, loff_t *ppos)
	68	{
	69	return ima_show_htable_value(buf, count, ppos, &ima_htable.len);
	70
	71	}
	72
828c0950	73	static const struct file_operations ima_measurements_count_ops = {
cdcd90f9 AB	74	.read = ima_show_measurements_count,
cdcd90f9 AB	75	.llseek = generic_file_llseek,
bab73937 MZ	76	};
	77
	78	/* returns pointer to hlist_node */
	79	static void ima_measurements_start(struct seq_file m, loff_t *pos)
	80	{
	81	loff_t l = *pos;
	82	struct ima_queue_entry *qe;
	83
	84	/* we need a lock since pos could point beyond last element */
	85	rcu_read_lock();
	86	list_for_each_entry_rcu(qe, &ima_measurements, later) {
	87	if (!l--) {
	88	rcu_read_unlock();
	89	return qe;
	90	}
	91	}
	92	rcu_read_unlock();
	93	return NULL;
	94	}
	95
	96	static void ima_measurements_next(struct seq_file m, void v, loff_t pos)
	97	{
	98	struct ima_queue_entry *qe = v;
	99
	100	/* lock protects when reading beyond last element
	101	* against concurrent list-extension
	102	*/
	103	rcu_read_lock();
089bc8e9	104	qe = list_entry_rcu(qe->later.next, struct ima_queue_entry, later);
bab73937 MZ	105	rcu_read_unlock();
	106	(*pos)++;
	107
	108	return (&qe->later == &ima_measurements) ? NULL : qe;
	109	}
	110
	111	static void ima_measurements_stop(struct seq_file m, void v)
	112	{
	113	}
	114
3ce1217d	115	void ima_putc(struct seq_file m, void data, int datalen)
bab73937 MZ	116	{
	117	while (datalen--)
	118	seq_putc(m, (char )data++);
	119	}
	120
	121	/* print format:
	122	* 32bit-le=pcr#
	123	* char[20]=template digest
	124	* 32bit-le=template name size
	125	* char[n]=template name
a71dc65d	126	* [eventdata length]
bab73937 MZ	127	* eventdata[n]=template specific data
bab73937 MZ	128	*/
7b8589cc	129	int ima_measurements_show(struct seq_file m, void v)
bab73937 MZ	130	{
	131	/* the list never shrinks, so we don't need a lock here */
	132	struct ima_queue_entry *qe = v;
	133	struct ima_template_entry *e;
7dbdb420	134	char *template_name;
d68a6fe9	135	u32 pcr, namelen, template_data_len; /* temporary fields */
3e8e5503	136	bool is_ima_template = false;
a71dc65d	137	int i;
bab73937 MZ	138
	139	/* get entry */
	140	e = qe->entry;
	141	if (e == NULL)
	142	return -1;
	143
7dbdb420 RS	144	template_name = (e->template_desc->name[0] != '\0') ?
	145	e->template_desc->name : e->template_desc->fmt;
	146
bab73937 MZ	147	/*
bab73937 MZ	148	* 1st: PCRIndex
5f6f027b ER	149	* PCR used defaults to the same (config option) in
5f6f027b ER	150	* little-endian format, unless set in policy
bab73937	151	*/
d68a6fe9 MZ	152	pcr = !ima_canonical_fmt ? e->pcr : cpu_to_le32(e->pcr);
d68a6fe9 MZ	153	ima_putc(m, &pcr, sizeof(e->pcr));
bab73937 MZ	154
bab73937 MZ	155	/* 2nd: template digest */
140d8022	156	ima_putc(m, e->digest, TPM_DIGEST_SIZE);
bab73937 MZ	157
bab73937 MZ	158	/* 3rd: template name size */
d68a6fe9 MZ	159	namelen = !ima_canonical_fmt ? strlen(template_name) :
d68a6fe9 MZ	160	cpu_to_le32(strlen(template_name));
2bb930ab	161	ima_putc(m, &namelen, sizeof(namelen));
bab73937 MZ	162
bab73937 MZ	163	/* 4th: template name */
d68a6fe9	164	ima_putc(m, template_name, strlen(template_name));
a71dc65d RS	165
a71dc65d RS	166	/* 5th: template length (except for 'ima' template) */
7dbdb420	167	if (strcmp(template_name, IMA_TEMPLATE_IMA_NAME) == 0)
3e8e5503 RS	168	is_ima_template = true;
3e8e5503 RS	169
d68a6fe9 MZ	170	if (!is_ima_template) {
	171	template_data_len = !ima_canonical_fmt ? e->template_data_len :
	172	cpu_to_le32(e->template_data_len);
	173	ima_putc(m, &template_data_len, sizeof(e->template_data_len));
	174	}
bab73937	175
a71dc65d RS	176	/* 6th: template specific data */
a71dc65d RS	177	for (i = 0; i < e->template_desc->num_fields; i++) {
3e8e5503 RS	178	enum ima_show_type show = IMA_SHOW_BINARY;
	179	struct ima_template_field *field = e->template_desc->fields[i];
	180
	181	if (is_ima_template && strcmp(field->field_id, "d") == 0)
	182	show = IMA_SHOW_BINARY_NO_FIELD_LEN;
c019e307 RS	183	if (is_ima_template && strcmp(field->field_id, "n") == 0)
c019e307 RS	184	show = IMA_SHOW_BINARY_OLD_STRING_FMT;
3e8e5503	185	field->field_show(m, show, &e->template_data[i]);
a71dc65d	186	}
bab73937 MZ	187	return 0;
	188	}
	189
88e9d34c	190	static const struct seq_operations ima_measurments_seqops = {
bab73937 MZ	191	.start = ima_measurements_start,
	192	.next = ima_measurements_next,
	193	.stop = ima_measurements_stop,
	194	.show = ima_measurements_show
	195	};
	196
	197	static int ima_measurements_open(struct inode inode, struct file file)
	198	{
	199	return seq_open(file, &ima_measurments_seqops);
	200	}
	201
828c0950	202	static const struct file_operations ima_measurements_ops = {
bab73937 MZ	203	.open = ima_measurements_open,
	204	.read = seq_read,
	205	.llseek = seq_lseek,
	206	.release = seq_release,
	207	};
	208
45b26133	209	void ima_print_digest(struct seq_file m, u8 digest, u32 size)
bab73937	210	{
45b26133	211	u32 i;
bab73937	212
140d8022	213	for (i = 0; i < size; i++)
bab73937 MZ	214	seq_printf(m, "%02x", *(digest + i));
	215	}
	216
bab73937 MZ	217	/* print in ascii */
	218	static int ima_ascii_measurements_show(struct seq_file m, void v)
	219	{
	220	/* the list never shrinks, so we don't need a lock here */
	221	struct ima_queue_entry *qe = v;
	222	struct ima_template_entry *e;
7dbdb420	223	char *template_name;
a71dc65d	224	int i;
bab73937 MZ	225
	226	/* get entry */
	227	e = qe->entry;
	228	if (e == NULL)
	229	return -1;
	230
7dbdb420 RS	231	template_name = (e->template_desc->name[0] != '\0') ?
	232	e->template_desc->name : e->template_desc->fmt;
	233
bab73937	234	/* 1st: PCR used (config option) */
5f6f027b	235	seq_printf(m, "%2d ", e->pcr);
bab73937 MZ	236
bab73937 MZ	237	/* 2nd: SHA1 template hash */
140d8022	238	ima_print_digest(m, e->digest, TPM_DIGEST_SIZE);
bab73937 MZ	239
bab73937 MZ	240	/* 3th: template name */
7dbdb420	241	seq_printf(m, " %s", template_name);
bab73937 MZ	242
bab73937 MZ	243	/* 4th: template specific data */
a71dc65d RS	244	for (i = 0; i < e->template_desc->num_fields; i++) {
	245	seq_puts(m, " ");
	246	if (e->template_data[i].len == 0)
	247	continue;
	248
	249	e->template_desc->fields[i]->field_show(m, IMA_SHOW_ASCII,
	250	&e->template_data[i]);
	251	}
	252	seq_puts(m, "\n");
bab73937 MZ	253	return 0;
	254	}
	255
88e9d34c	256	static const struct seq_operations ima_ascii_measurements_seqops = {
bab73937 MZ	257	.start = ima_measurements_start,
	258	.next = ima_measurements_next,
	259	.stop = ima_measurements_stop,
	260	.show = ima_ascii_measurements_show
	261	};
	262
	263	static int ima_ascii_measurements_open(struct inode inode, struct file file)
	264	{
	265	return seq_open(file, &ima_ascii_measurements_seqops);
	266	}
	267
828c0950	268	static const struct file_operations ima_ascii_measurements_ops = {
bab73937 MZ	269	.open = ima_ascii_measurements_open,
	270	.read = seq_read,
	271	.llseek = seq_lseek,
	272	.release = seq_release,
	273	};
	274
7429b092 DK	275	static ssize_t ima_read_policy(char *path)
	276	{
	277	void *data;
	278	char *datap;
	279	loff_t size;
	280	int rc, pathlen = strlen(path);
	281
	282	char *p;
	283
	284	/* remove \n */
	285	datap = path;
	286	strsep(&datap, "\n");
	287
	288	rc = kernel_read_file_from_path(path, &data, &size, 0, READING_POLICY);
	289	if (rc < 0) {
58441dc8	290	pr_warn("Unable to open file: %s (%d)", path, rc);
7429b092 DK	291	return rc;
	292	}
	293
	294	datap = data;
	295	while (size > 0 && (p = strsep(&datap, "\n"))) {
	296	pr_debug("rule: %s\n", p);
	297	rc = ima_parse_add_rule(p);
	298	if (rc < 0)
	299	break;
	300	size -= rc;
	301	}
	302
	303	vfree(data);
	304	if (rc < 0)
	305	return rc;
	306	else if (size)
	307	return -EINVAL;
	308	else
	309	return pathlen;
	310	}
	311
4af4662f MZ	312	static ssize_t ima_write_policy(struct file file, const char __user buf,
	313	size_t datalen, loff_t *ppos)
	314	{
6427e6c7	315	char *data;
6ccd0456	316	ssize_t result;
4af4662f MZ	317
4af4662f MZ	318	if (datalen >= PAGE_SIZE)
6ccd0456 EP	319	datalen = PAGE_SIZE - 1;
	320
	321	/* No partial writes. */
	322	result = -EINVAL;
	323	if (*ppos != 0)
	324	goto out;
	325
b4e28030 GT	326	data = memdup_user_nul(buf, datalen);
	327	if (IS_ERR(data)) {
	328	result = PTR_ERR(data);
6ccd0456	329	goto out;
b4e28030	330	}
6ccd0456	331
6427e6c7 PM	332	result = mutex_lock_interruptible(&ima_write_mutex);
	333	if (result < 0)
	334	goto out_free;
6427e6c7	335
19f8a847	336	if (data[0] == '/') {
7429b092	337	result = ima_read_policy(data);
19f8a847 MZ	338	} else if (ima_appraise & IMA_APPRAISE_POLICY) {
	339	pr_err("IMA: signed policy file (specified as an absolute pathname) required\n");
	340	integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL, NULL,
	341	"policy_update", "signed policy required",
	342	1, 0);
	343	if (ima_appraise & IMA_APPRAISE_ENFORCE)
	344	result = -EACCES;
	345	} else {
7429b092	346	result = ima_parse_add_rule(data);
19f8a847	347	}
7429b092	348	mutex_unlock(&ima_write_mutex);
6427e6c7 PM	349	out_free:
6427e6c7 PM	350	kfree(data);
6ccd0456 EP	351	out:
	352	if (result < 0)
	353	valid_policy = 0;
38d859f9	354
6ccd0456	355	return result;
4af4662f MZ	356	}
4af4662f MZ	357
bab73937 MZ	358	static struct dentry *ima_dir;
	359	static struct dentry *binary_runtime_measurements;
	360	static struct dentry *ascii_runtime_measurements;
	361	static struct dentry *runtime_measurements_count;
	362	static struct dentry *violations;
4af4662f MZ	363	static struct dentry *ima_policy;
4af4662f MZ	364
0716abbb DK	365	enum ima_fs_flags {
	366	IMA_FS_BUSY,
	367	};
	368
	369	static unsigned long ima_fs_flags;
	370
80eae209 PM	371	#ifdef CONFIG_IMA_READ_POLICY
	372	static const struct seq_operations ima_policy_seqops = {
	373	.start = ima_policy_start,
	374	.next = ima_policy_next,
	375	.stop = ima_policy_stop,
	376	.show = ima_policy_show,
	377	};
	378	#endif
	379
f4bd857b MZ	380	/*
	381	* ima_open_policy: sequentialize access to the policy file
	382	*/
2bb930ab	383	static int ima_open_policy(struct inode inode, struct file filp)
f4bd857b	384	{
80eae209 PM	385	if (!(filp->f_flags & O_WRONLY)) {
80eae209 PM	386	#ifndef CONFIG_IMA_READ_POLICY
f850a7c0	387	return -EACCES;
80eae209 PM	388	#else
	389	if ((filp->f_flags & O_ACCMODE) != O_RDONLY)
	390	return -EACCES;
	391	if (!capable(CAP_SYS_ADMIN))
	392	return -EPERM;
	393	return seq_open(filp, &ima_policy_seqops);
	394	#endif
	395	}
0716abbb DK	396	if (test_and_set_bit(IMA_FS_BUSY, &ima_fs_flags))
	397	return -EBUSY;
	398	return 0;
f4bd857b MZ	399	}
f4bd857b MZ	400
4af4662f MZ	401	/*
	402	* ima_release_policy - start using the new measure policy rules.
	403	*
	404	* Initially, ima_measure points to the default policy rules, now
f4bd857b MZ	405	* point to the new policy rules, and remove the securityfs policy file,
f4bd857b MZ	406	* assuming a valid policy.
4af4662f MZ	407	*/
	408	static int ima_release_policy(struct inode inode, struct file file)
	409	{
0716abbb DK	410	const char *cause = valid_policy ? "completed" : "failed";
0716abbb DK	411
80eae209	412	if ((file->f_flags & O_ACCMODE) == O_RDONLY)
9a11a189	413	return seq_release(inode, file);
80eae209	414
0112721d SL	415	if (valid_policy && ima_check_policy() < 0) {
	416	cause = "failed";
	417	valid_policy = 0;
	418	}
	419
0716abbb DK	420	pr_info("IMA: policy update %s\n", cause);
	421	integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL, NULL,
	422	"policy_update", cause, !valid_policy, 0);
	423
4af4662f MZ	424	if (!valid_policy) {
4af4662f MZ	425	ima_delete_rules();
f4bd857b	426	valid_policy = 1;
0716abbb	427	clear_bit(IMA_FS_BUSY, &ima_fs_flags);
4af4662f MZ	428	return 0;
4af4662f MZ	429	}
80eae209	430
4af4662f	431	ima_update_policy();
2068626d	432	#if !defined(CONFIG_IMA_WRITE_POLICY) && !defined(CONFIG_IMA_READ_POLICY)
4af4662f MZ	433	securityfs_remove(ima_policy);
4af4662f MZ	434	ima_policy = NULL;
2068626d	435	#elif defined(CONFIG_IMA_WRITE_POLICY)
38d859f9 PM	436	clear_bit(IMA_FS_BUSY, &ima_fs_flags);
38d859f9 PM	437	#endif
4af4662f MZ	438	return 0;
	439	}
	440
828c0950	441	static const struct file_operations ima_measure_policy_ops = {
f4bd857b	442	.open = ima_open_policy,
4af4662f	443	.write = ima_write_policy,
80eae209	444	.read = seq_read,
cdcd90f9 AB	445	.release = ima_release_policy,
cdcd90f9 AB	446	.llseek = generic_file_llseek,
4af4662f	447	};
bab73937	448
932995f0	449	int __init ima_fs_init(void)
bab73937 MZ	450	{
	451	ima_dir = securityfs_create_dir("ima", NULL);
	452	if (IS_ERR(ima_dir))
	453	return -1;
	454
	455	binary_runtime_measurements =
	456	securityfs_create_file("binary_runtime_measurements",
	457	S_IRUSR \| S_IRGRP, ima_dir, NULL,
	458	&ima_measurements_ops);
	459	if (IS_ERR(binary_runtime_measurements))
	460	goto out;
	461
	462	ascii_runtime_measurements =
	463	securityfs_create_file("ascii_runtime_measurements",
	464	S_IRUSR \| S_IRGRP, ima_dir, NULL,
	465	&ima_ascii_measurements_ops);
	466	if (IS_ERR(ascii_runtime_measurements))
	467	goto out;
	468
	469	runtime_measurements_count =
	470	securityfs_create_file("runtime_measurements_count",
	471	S_IRUSR \| S_IRGRP, ima_dir, NULL,
	472	&ima_measurements_count_ops);
	473	if (IS_ERR(runtime_measurements_count))
	474	goto out;
	475
	476	violations =
	477	securityfs_create_file("violations", S_IRUSR \| S_IRGRP,
	478	ima_dir, NULL, &ima_htable_violations_ops);
	479	if (IS_ERR(violations))
	480	goto out;
	481
80eae209	482	ima_policy = securityfs_create_file("policy", POLICY_FILE_FLAGS,
4af4662f MZ	483	ima_dir, NULL,
	484	&ima_measure_policy_ops);
	485	if (IS_ERR(ima_policy))
	486	goto out;
bab73937	487
4af4662f	488	return 0;
bab73937	489	out:
0ea4f8ae	490	securityfs_remove(violations);
bab73937 MZ	491	securityfs_remove(runtime_measurements_count);
	492	securityfs_remove(ascii_runtime_measurements);
	493	securityfs_remove(binary_runtime_measurements);
	494	securityfs_remove(ima_dir);
4af4662f	495	securityfs_remove(ima_policy);
bab73937 MZ	496	return -1;
bab73937 MZ	497	}