security/pfe/pfk_ice.c

/* Copyright (c) 2015-2018, The Linux Foundation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 and
 * only version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/io.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/async.h>
#include <linux/mm.h>
#include <linux/of.h>
#include <linux/device-mapper.h>
#include <soc/qcom/scm.h>
#include <soc/qcom/qseecomi.h>
#include <crypto/ice.h>
#include "pfk_ice.h"

/**********************************/
/** global definitions		 **/
/**********************************/

#define TZ_ES_INVALIDATE_ICE_KEY 0x3
#define TZ_ES_CONFIG_SET_ICE_KEY 0x4

/* index 0 and 1 is reserved for FDE */
#define MIN_ICE_KEY_INDEX 2

#define MAX_ICE_KEY_INDEX 31

#define TZ_ES_CONFIG_SET_ICE_KEY_ID \
	TZ_SYSCALL_CREATE_SMC_ID(TZ_OWNER_SIP, TZ_SVC_ES, \
	TZ_ES_CONFIG_SET_ICE_KEY)

#define TZ_ES_INVALIDATE_ICE_KEY_ID \
		TZ_SYSCALL_CREATE_SMC_ID(TZ_OWNER_SIP, \
			TZ_SVC_ES, TZ_ES_INVALIDATE_ICE_KEY)

#define TZ_ES_INVALIDATE_ICE_KEY_PARAM_ID \
	TZ_SYSCALL_CREATE_PARAM_ID_1( \
	TZ_SYSCALL_PARAM_TYPE_VAL)

#define TZ_ES_CONFIG_SET_ICE_KEY_PARAM_ID \
	TZ_SYSCALL_CREATE_PARAM_ID_5( \
	TZ_SYSCALL_PARAM_TYPE_VAL, \
	TZ_SYSCALL_PARAM_TYPE_BUF_RW, TZ_SYSCALL_PARAM_TYPE_VAL, \
	TZ_SYSCALL_PARAM_TYPE_VAL, TZ_SYSCALL_PARAM_TYPE_VAL)

#define CONTEXT_SIZE 0x1000

#define ICE_BUFFER_SIZE 64

static uint8_t ice_buffer[ICE_BUFFER_SIZE];

enum {
	ICE_CIPHER_MODE_XTS_128 = 0,
	ICE_CIPHER_MODE_CBC_128 = 1,
	ICE_CIPHER_MODE_XTS_256 = 3,
	ICE_CIPHER_MODE_CBC_256 = 4
};

static int set_key(uint32_t index, const uint8_t *key, const uint8_t *salt,
		unsigned int data_unit)
{
	struct scm_desc desc = {0};
	int ret = 0;
	uint32_t smc_id = 0;
	char *tzbuf = (char *)ice_buffer;
	uint32_t size = ICE_BUFFER_SIZE / 2;

	if (!tzbuf) {
		pr_err("%s No Memory\n", __func__);
		return -ENOMEM;
	}

	memset(tzbuf, 0, ICE_BUFFER_SIZE);

	memcpy(ice_buffer, key, size);
	memcpy(ice_buffer+size, salt, size);

	dmac_flush_range(tzbuf, tzbuf + ICE_BUFFER_SIZE);

	smc_id = TZ_ES_CONFIG_SET_ICE_KEY_ID;

	desc.arginfo = TZ_ES_CONFIG_SET_ICE_KEY_PARAM_ID;
	desc.args[0] = index;
	desc.args[1] = virt_to_phys(tzbuf);
	desc.args[2] = ICE_BUFFER_SIZE;
	desc.args[3] = ICE_CIPHER_MODE_XTS_256;
	desc.args[4] = data_unit;

	ret = scm_call2_noretry(smc_id, &desc);
	if (ret)
		pr_err("%s:SCM call Error: 0x%x\n", __func__, ret);

	return ret;
}

static int clear_key(uint32_t index)
{
	struct scm_desc desc = {0};
	int ret = 0;
	uint32_t smc_id = 0;

	smc_id = TZ_ES_INVALIDATE_ICE_KEY_ID;

	desc.arginfo = TZ_ES_INVALIDATE_ICE_KEY_PARAM_ID;
	desc.args[0] = index;

	ret = scm_call2_noretry(smc_id, &desc);
	if (ret)
		pr_err("%s:SCM call Error: 0x%x\n", __func__, ret);
	return ret;
}

int qti_pfk_ice_set_key(uint32_t index, uint8_t *key, uint8_t *salt,
			char *storage_type, unsigned int data_unit)
{
	int ret = 0, ret1 = 0;
	char *s_type = storage_type;

	if (index < MIN_ICE_KEY_INDEX || index > MAX_ICE_KEY_INDEX) {
		pr_err("%s Invalid index %d\n", __func__, index);
		return -EINVAL;
	}
	if (!key || !salt) {
		pr_err("%s Invalid key/salt\n", __func__);
		return -EINVAL;
	}

	if (s_type == NULL) {
		pr_err("%s Invalid Storage type\n", __func__);
		return -EINVAL;
	}

	ret = qcom_ice_setup_ice_hw((const char *)s_type, true);
	if (ret) {
		pr_err("%s: could not enable clocks: %d\n", __func__, ret);
		goto out;
	}

	ret = set_key(index, key, salt, data_unit);
	if (ret) {
		pr_err("%s: Set Key Error: %d\n", __func__, ret);
		if (ret == -EBUSY) {
			if (qcom_ice_setup_ice_hw((const char *)s_type, false))
				pr_err("%s: clock disable failed\n", __func__);
				goto out;
		}
		/* Try to invalidate the key to keep ICE in proper state */
		ret1 = clear_key(index);
		if (ret1)
			pr_err("%s: Invalidate key error: %d\n", __func__, ret);
	}

	ret1 = qcom_ice_setup_ice_hw((const char *)s_type, false);
	if (ret)
		pr_err("%s: Error %d disabling clocks\n", __func__, ret);

out:
	return ret;
}

int qti_pfk_ice_invalidate_key(uint32_t index, char *storage_type)
{
	int ret = 0;

	if (index < MIN_ICE_KEY_INDEX || index > MAX_ICE_KEY_INDEX) {
		pr_err("%s Invalid index %d\n", __func__, index);
		return -EINVAL;
	}

	if (storage_type == NULL) {
		pr_err("%s Invalid Storage type\n", __func__);
		return -EINVAL;
	}

	ret = qcom_ice_setup_ice_hw((const char *)storage_type, true);
	if (ret) {
		pr_err("%s: could not enable clocks: 0x%x\n", __func__, ret);
		return ret;
	}

	ret = clear_key(index);
	if (ret)
		pr_err("%s: Invalidate key error: %d\n", __func__, ret);

	if (qcom_ice_setup_ice_hw((const char *)storage_type, false))
		pr_err("%s: could not disable clocks\n", __func__);

	return ret;
}