platform: msm_shared: Add support for verified boot

Add support for verified boot

Change-Id: I466d62ef745ab1af121ff588334020d447d02541
diff --git a/platform/msm_shared/boot_verifier.c b/platform/msm_shared/boot_verifier.c
new file mode 100644
index 0000000..234f06a
--- /dev/null
+++ b/platform/msm_shared/boot_verifier.c
@@ -0,0 +1,612 @@
+/*
+ * Copyright (c) 2014-2015, The Linux Foundation. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above
+ *    copyright notice, this list of conditions and the following
+ *    disclaimer in the documentation and/or other materials provided
+ *    with the distribution.
+ *  * Neither the name of The Linux Foundation nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+
+ * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+ * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
+ * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <stdlib.h>
+#include <stdint.h>
+#include <crypto_hash.h>
+#include <boot_verifier.h>
+#include <image_verify.h>
+#include <mmc.h>
+#include <oem_keystore.h>
+#include <openssl/asn1t.h>
+#include <openssl/x509.h>
+#include <partition_parser.h>
+#include <rsa.h>
+#include <string.h>
+#include <openssl/err.h>
+#include <qseecom_lk_api.h>
+#include <secapp_loader.h>
+#include <target.h>
+
+static KEYSTORE *oem_keystore;
+static KEYSTORE *user_keystore;
+static uint32_t dev_boot_state = RED;
+char KEYSTORE_PTN_NAME[] = "keystore";
+RSA *rsa_from_cert = NULL;
+
+ASN1_SEQUENCE(AUTH_ATTR) ={
+	ASN1_SIMPLE(AUTH_ATTR, target, ASN1_PRINTABLESTRING),
+	ASN1_SIMPLE(AUTH_ATTR, len, ASN1_INTEGER)
+} ASN1_SEQUENCE_END(AUTH_ATTR)
+IMPLEMENT_ASN1_FUNCTIONS(AUTH_ATTR)
+
+	ASN1_SEQUENCE(VERIFIED_BOOT_SIG) = {
+		ASN1_SIMPLE(VERIFIED_BOOT_SIG, version, ASN1_INTEGER),
+		ASN1_SIMPLE(VERIFIED_BOOT_SIG, certificate, X509),
+		ASN1_SIMPLE(VERIFIED_BOOT_SIG, algor, X509_ALGOR),
+		ASN1_SIMPLE(VERIFIED_BOOT_SIG, auth_attr, AUTH_ATTR),
+		ASN1_SIMPLE(VERIFIED_BOOT_SIG, sig, ASN1_OCTET_STRING)
+	} ASN1_SEQUENCE_END(VERIFIED_BOOT_SIG)
+IMPLEMENT_ASN1_FUNCTIONS(VERIFIED_BOOT_SIG)
+
+	ASN1_SEQUENCE(KEY) = {
+		ASN1_SIMPLE(KEY, algorithm_id, X509_ALGOR),
+		ASN1_SIMPLE(KEY, key_material, RSAPublicKey)
+	}ASN1_SEQUENCE_END(KEY)
+IMPLEMENT_ASN1_FUNCTIONS(KEY);
+
+ASN1_SEQUENCE(KEYBAG) = {
+	ASN1_SIMPLE(KEYBAG, mykey, KEY)
+}ASN1_SEQUENCE_END(KEYBAG)
+IMPLEMENT_ASN1_FUNCTIONS(KEYBAG)
+
+	ASN1_SEQUENCE(KEYSTORE_INNER) = {
+		ASN1_SIMPLE(KEYSTORE_INNER, version, ASN1_INTEGER),
+		ASN1_SIMPLE(KEYSTORE_INNER, mykeybag, KEYBAG)
+	} ASN1_SEQUENCE_END(KEYSTORE_INNER)
+IMPLEMENT_ASN1_FUNCTIONS(KEYSTORE_INNER)
+
+	ASN1_SEQUENCE(KEYSTORE) = {
+		ASN1_SIMPLE(KEYSTORE, version, ASN1_INTEGER),
+		ASN1_SIMPLE(KEYSTORE, mykeybag, KEYBAG),
+		ASN1_SIMPLE(KEYSTORE, sig, VERIFIED_BOOT_SIG)
+	} ASN1_SEQUENCE_END(KEYSTORE)
+IMPLEMENT_ASN1_FUNCTIONS(KEYSTORE)
+
+static uint32_t read_der_message_length(unsigned char* input)
+{
+	uint32_t len = 0;
+	int pos = 0;
+	uint8_t len_bytes = 1;
+
+	/* Check if input starts with Sequence id (0X30) */
+	if(input[pos] != 0x30)
+		return len;
+	pos++;
+
+	/* A length of 0xAABBCCDD in DER encoded messages would be sequence of
+	   following octets 0xAA, 0xBB, 0XCC, 0XDD.
+
+	   To read length - read each octet and shift left by 1 octect before
+	   reading next octet.
+	*/
+	/* check if short or long length form */
+	if(input[pos] & 0x80)
+	{
+		len_bytes = (input[pos] & ~(0x80));
+		pos++;
+	}
+	while(len_bytes)
+	{
+		/* Shift len by 1 octet */
+		len = len << 8;
+
+		/* Read next octet */
+		len = len | input[pos];
+		pos++; len_bytes--;
+	}
+
+	/* Add number of octets representing sequence id and length  */
+	len += pos;
+
+	return len;
+}
+
+static int verify_digest(unsigned char* input, unsigned char *digest, int hash_size)
+{
+	int ret = -1;
+	X509_SIG *sig = NULL;
+	uint32_t len = read_der_message_length(input);
+	if(!len)
+	{
+		dprintf(CRITICAL, "boot_verifier: Signature length is invalid.\n");
+		return ret;
+	}
+
+	sig = d2i_X509_SIG(NULL, (const unsigned char **) &input, len);
+	if(sig == NULL)
+	{
+		dprintf(CRITICAL, "boot_verifier: Reading digest failed\n");
+		return ret;
+	}
+
+	if(sig->digest->length != SHA256_SIZE)
+	{
+		dprintf(CRITICAL, "boot_verifier: Digest length error.\n");
+		goto verify_digest_error;
+	}
+
+	if(memcmp(sig->digest->data, digest, hash_size) == 0)
+		ret = 0;
+
+verify_digest_error:
+	if(sig != NULL)
+		X509_SIG_free(sig);
+
+	return ret;
+}
+
+static int add_attribute_to_img(unsigned char *ptr, AUTH_ATTR *input)
+{
+	return i2d_AUTH_ATTR(input, &ptr);
+}
+
+static bool boot_verify_compare_sha256(unsigned char *image_ptr,
+		unsigned int image_size, unsigned char *signature_ptr, RSA *rsa)
+{
+	int ret = -1;
+	bool auth = false;
+	unsigned char *plain_text = NULL;
+	unsigned int digest[8];
+
+	plain_text = (unsigned char *)calloc(sizeof(char), SIGNATURE_SIZE);
+	if (plain_text == NULL) {
+		dprintf(CRITICAL, "boot_verifier: Calloc failed during verification\n");
+		goto cleanup;
+	}
+
+	/* Calculate SHA256sum */
+	image_find_digest(image_ptr, image_size, CRYPTO_AUTH_ALG_SHA256,
+			(unsigned char *)&digest);
+
+	/* Find digest from the image */
+	ret = image_decrypt_signature_rsa(signature_ptr, plain_text, rsa);
+
+	dprintf(SPEW, "boot_verifier: Return of RSA_public_decrypt = %d\n",
+			ret);
+
+	ret = verify_digest(plain_text, (unsigned char*)digest, SHA256_SIZE);
+	if(ret == 0)
+	{
+		auth = true;
+#ifdef TZ_SAVE_KERNEL_HASH
+		save_kernel_hash((unsigned char *) &digest, CRYPTO_AUTH_ALG_SHA256);
+#endif
+	}
+
+cleanup:
+	if (plain_text != NULL)
+		free(plain_text);
+	EVP_cleanup();
+	CRYPTO_cleanup_all_ex_data();
+	ERR_remove_thread_state(NULL);
+	return auth;
+
+}
+
+static bool verify_image_with_sig(unsigned char* img_addr, uint32_t img_size,
+		char *pname, VERIFIED_BOOT_SIG *sig, KEYSTORE *ks)
+{
+	bool ret = false;
+	uint32_t len;
+	int shift_bytes;
+	RSA *rsa = NULL;
+	bool keystore_verification = false;
+	EVP_PKEY* key = NULL;
+
+	if(!strcmp(pname, "keystore"))
+		keystore_verification = true;
+
+	/* Verify target name */
+	if(strncmp((char*)(sig->auth_attr->target->data), pname,
+				sig->auth_attr->target->length) ||
+				(strlen(pname) != (unsigned long) sig->auth_attr->target->length))
+	{
+		dprintf(CRITICAL,
+				"boot_verifier: verification failure due to target name mismatch\n");
+		goto verify_image_with_sig_error;
+	}
+	/* Read image size from signature */
+	/* A len = 0xAABBCC (represented by 3 octets) would be stored in
+	   len->data as 0X00CCBBAA and len->length as 3(octets).
+
+	   To read len we need to left shift data to number of missing octets and
+	   then change it to host long
+	 */
+	len = *((uint32_t*)sig->auth_attr->len->data);
+	shift_bytes = sizeof(uint32_t) - sig->auth_attr->len->length;
+	if(shift_bytes > 0) {
+		len = len << (shift_bytes*8);
+	}
+	len = ntohl(len);
+
+	/* Verify image size*/
+	if(len != img_size)
+	{
+		dprintf(CRITICAL,
+				"boot_verifier: image length is different. (%d vs %d)\n",
+				len, img_size);
+		goto verify_image_with_sig_error;
+	}
+
+	/* append attribute to image */
+	if(!keystore_verification)
+	{
+		// verifying a non keystore partition
+		img_size += add_attribute_to_img((unsigned char*)(img_addr + img_size),
+				sig->auth_attr);
+	}
+
+	/* compare SHA256SUM of image with value in signature */
+	if(ks != NULL)
+	{
+		// use rsa from keystore
+		rsa = ks->mykeybag->mykey->key_material;
+	}
+	else
+	{
+		dprintf(CRITICAL, "%s:%d: Keystore is null\n", __func__, __LINE__);
+		ASSERT(0);
+	}
+
+	// verify boot.img with rsa from oem keystore
+	if((ret = boot_verify_compare_sha256(img_addr, img_size,
+			(unsigned char*)sig->sig->data, rsa)))
+
+	{
+		dprintf(SPEW, "Verified boot.img with oem keystore\n");
+		boot_verify_send_event(BOOTIMG_KEYSTORE_VERIFICATION_PASS);
+		goto verify_image_with_sig_done;
+	}
+	else
+	{
+		dprintf(INFO, "Verification with oem keystore failed. Use embedded certificate for verification\n");
+		// get the public key from certificate in boot.img
+		if ((key = X509_get_pubkey(sig->certificate)))
+		{
+			// convert to rsa key format
+			dprintf(INFO, "RSA KEY found from the embedded certificate\n");
+			rsa = EVP_PKEY_get1_RSA(key);
+			rsa_from_cert = rsa;
+		}
+		else
+		{
+			dprintf(CRITICAL, "Unable to extract public key from certificate\n");
+			ASSERT(0);
+		}
+	}
+
+	// verify boot.img with rsa from embedded certificate
+	if ((ret = boot_verify_compare_sha256(img_addr, img_size,
+			(unsigned char*)sig->sig->data, rsa)))
+	{
+		dprintf(SPEW, "Verified boot.img with embedded certificate in boot image\n");
+		boot_verify_send_event(BOOTIMG_EMBEDDED_CERT_VERIFICATION_PASS);
+		goto verify_image_with_sig_done;
+	}
+	else
+	{
+		dprintf(INFO, "verified for red state\n");
+		boot_verify_send_event(BOOTIMG_VERIFICATION_FAIL);
+		goto verify_image_with_sig_done;
+	}
+
+verify_image_with_sig_error:
+verify_image_with_sig_done:
+	return ret;
+}
+
+static int encode_inner_keystore(unsigned char *ptr, KEYSTORE *ks)
+{
+	int ret = 0;
+	KEYSTORE_INNER  *ks_inner = KEYSTORE_INNER_new();
+	if (ks_inner == NULL)
+		return ret;
+	ASN1_INTEGER *tmp_version = ks_inner->version;
+	KEYBAG *tmp_mykeybag = ks_inner->mykeybag;
+
+	ks_inner->version = ks->version;
+	ks_inner->mykeybag = ks->mykeybag;
+	ret = i2d_KEYSTORE_INNER(ks_inner, &ptr);
+
+	ks_inner->version = tmp_version;
+	ks_inner->mykeybag = tmp_mykeybag;
+
+	if(ks_inner != NULL)
+		KEYSTORE_INNER_free(ks_inner);
+	return ret;
+}
+
+static bool verify_keystore(unsigned char * ks_addr, KEYSTORE *ks)
+{
+	bool ret = false;
+	unsigned char * ptr = ks_addr;
+	uint32_t inner_len = encode_inner_keystore(ptr, ks);
+	ret = verify_image_with_sig(ks_addr, inner_len, "keystore", ks->sig,
+			oem_keystore);
+	return ret;
+}
+
+static void read_oem_keystore()
+{
+	KEYSTORE *ks = NULL;
+	uint32_t len = 0;
+	const unsigned char *input = OEM_KEYSTORE;
+
+	if(oem_keystore != NULL)
+		return;
+
+	len = read_der_message_length((unsigned char *)input);
+	if(!len)
+	{
+		dprintf(CRITICAL, "boot_verifier: oem keystore length is invalid.\n");
+		return;
+	}
+
+	ks = d2i_KEYSTORE(NULL, (const unsigned char **) &input, len);
+	if(ks != NULL)
+	{
+		oem_keystore = ks;
+		user_keystore = ks;
+	}
+}
+
+uint32_t boot_verify_keystore_init()
+{
+	/* Read OEM Keystore */
+	read_oem_keystore();
+
+	return dev_boot_state;
+}
+
+bool send_rot_command(uint32_t is_unlocked)
+{
+	int ret = 0;
+	unsigned char *input = NULL;
+	char *rot_input = NULL;
+	unsigned int digest[9] = {0}, final_digest[8] = {0};
+	uint32_t auth_algo = CRYPTO_AUTH_ALG_SHA256;
+	uint32_t boot_device_state = boot_verify_get_state();
+	int app_handle = 0;
+	uint32_t len_oem_rsa = 0, len_from_cert = 0;
+	km_set_rot_req_t *read_req;
+	km_set_rot_rsp_t read_rsp;
+	app_handle = get_secapp_handle();
+	int n = 0, e = 0;
+	switch (boot_device_state)
+	{
+		case GREEN:
+			// Locked device and boot.img verified against OEM keystore.
+			// n is length of modulus and e is length exponent
+			n = BN_num_bytes(oem_keystore->mykeybag->mykey->key_material->n);
+			e = BN_num_bytes(oem_keystore->mykeybag->mykey->key_material->e);
+			len_oem_rsa = n + e;
+			if(!(input = malloc(len_oem_rsa)))
+			{
+				dprintf(CRITICAL, "Failed to allocate memory for ROT structure\n");
+				ASSERT(0);
+			}
+			// convert the absolute value on n, e to big endian form
+			BN_bn2bin(oem_keystore->mykeybag->mykey->key_material->n, input);
+			BN_bn2bin(oem_keystore->mykeybag->mykey->key_material->e, input+n);
+			// Hash of key from OEM KEYSTORE
+			hash_find((unsigned char *)input, len_oem_rsa, (unsigned char *) &digest, auth_algo);
+			digest[8] = is_unlocked;
+			break;
+		case YELLOW:
+		case RED:
+			// Locked device and boot.img passed (yellow) or failed (red) verification with the certificate embedded to the boot.img.
+			if (!rsa_from_cert)
+			{
+				dprintf(CRITICAL, "RSA is null from the embedded certificate\n");
+				ASSERT(0);
+			}
+			// n is length of modulus and e is length exponent
+			n = BN_num_bytes(rsa_from_cert->n);
+			e = BN_num_bytes(rsa_from_cert->e);
+			len_from_cert = n + e;
+			if(!(input = malloc(len_from_cert)))
+			{
+				dprintf(CRITICAL, "Failed to allocate memory for ROT structure\n");
+				ASSERT(0);
+			}
+			// convert the absolute value on n, e to big endian form
+			BN_bn2bin(rsa_from_cert->n, input);
+			BN_bn2bin(rsa_from_cert->e, input+n);
+			// Hash of key from certificate in boot image
+			hash_find((unsigned char *)input, len_from_cert, (unsigned char *) &digest, auth_algo);
+			digest[8] = is_unlocked;
+			break;
+		case ORANGE:
+			// Unlocked device and no verification done.
+			// Send the hash of boot device state
+			input = NULL;
+			digest[0] = is_unlocked;
+			break;
+	}
+	// Hash of hash(key) + device state (locked/unlocked)
+	hash_find((unsigned char *) digest, sizeof(digest), (unsigned char *)&final_digest, auth_algo);
+	dprintf(SPEW, "Digest: ");
+	for(uint8_t i = 0; i < 8; i++)
+		dprintf(SPEW, "0x%x ", final_digest[i]);
+	dprintf(SPEW, "\n");
+	if(!(read_req = malloc(sizeof(km_set_rot_req_t) + sizeof(final_digest))))
+	{
+		dprintf(CRITICAL, "Failed to allocate memory for ROT structure\n");
+		ASSERT(0);
+	}
+
+	void *cpy_ptr = (uint8_t *) read_req + sizeof(km_set_rot_req_t);
+	// set ROT stucture
+	read_req->cmd_id = KEYMASTER_SET_ROT;
+	read_req->rot_ofset = (uint32_t) sizeof(km_set_rot_req_t);
+	read_req->rot_size  = sizeof(final_digest);
+	// copy the digest
+	memcpy(cpy_ptr, (void *) &final_digest, sizeof(final_digest));
+	dprintf(SPEW, "Sending Root of Trust to trustzone: start\n");
+
+	ret = qseecom_send_command(app_handle, (void*) read_req, sizeof(km_set_rot_req_t) + sizeof(final_digest), (void*) &read_rsp, sizeof(read_rsp));
+	if (ret < 0 || read_rsp.status < 0)
+	{
+		dprintf(CRITICAL, "QSEEcom command for Sending Root of Trust returned error: %d\n", read_rsp.status);
+		if(input)
+			free(input);
+		free(read_req);
+		free(rot_input);
+		return false;
+	}
+	dprintf(SPEW, "Sending Root of Trust to trustzone: end\n");
+	if(input)
+		free(input);
+	free(read_req);
+	free(rot_input);
+	return true;
+}
+
+bool boot_verify_image(unsigned char* img_addr, uint32_t img_size, char *pname)
+{
+	bool ret = false;
+	VERIFIED_BOOT_SIG *sig = NULL;
+	unsigned char* sig_addr = (unsigned char*)(img_addr + img_size);
+	uint32_t sig_len = read_der_message_length(sig_addr);
+
+	if(dev_boot_state == ORANGE)
+	{
+		dprintf(INFO, "boot_verifier: Device is in ORANGE boot state.\n");
+		dprintf(INFO, "boot_verifier: Skipping boot verification.\n");
+		return false;
+	}
+
+	if(!sig_len)
+	{
+		dprintf(CRITICAL, "boot_verifier: Error while reading signature length.\n");
+		ASSERT(0);
+	}
+
+	if((sig = d2i_VERIFIED_BOOT_SIG(NULL, (const unsigned char **) &sig_addr, sig_len)) == NULL)
+	{
+		dprintf(CRITICAL,
+				"boot_verifier: verification failure due to target name mismatch\n");
+		ASSERT(0);
+	}
+
+	ret = verify_image_with_sig(img_addr, img_size, pname, sig, user_keystore);
+
+	if(sig != NULL)
+		VERIFIED_BOOT_SIG_free(sig);
+	return ret;
+}
+
+void boot_verify_send_event(uint32_t event)
+{
+	switch(event)
+	{
+		case BOOT_INIT:
+			dev_boot_state = GREEN;
+			break;
+		case BOOTIMG_KEYSTORE_VERIFICATION_PASS:
+			dev_boot_state = GREEN;
+			break;
+		case BOOTIMG_EMBEDDED_CERT_VERIFICATION_PASS:
+			if(dev_boot_state == GREEN)
+				dev_boot_state = YELLOW;
+			break;
+		case BOOTIMG_VERIFICATION_FAIL:
+			if(dev_boot_state == GREEN || dev_boot_state == YELLOW)
+				dev_boot_state = RED;
+			break;
+		case DEV_UNLOCK:
+			dev_boot_state = ORANGE;
+			break;
+		case USER_DENIES:
+			if(dev_boot_state == YELLOW || dev_boot_state == ORANGE)
+				dev_boot_state = RED;
+			break;
+	}
+}
+
+uint32_t boot_verify_get_state()
+{
+	return dev_boot_state;
+}
+
+void boot_verify_print_state()
+{
+	switch(dev_boot_state)
+	{
+		case GREEN:
+			dprintf(INFO, "boot_verifier: Device is in GREEN boot state.\n");
+			break;
+		case ORANGE:
+			dprintf(INFO, "boot_verifier: Device is in ORANGE boot state.\n");
+			break;
+		case YELLOW:
+			dprintf(INFO, "boot_verifier: Device is in YELLOW boot state.\n");
+			break;
+		case RED:
+			dprintf(INFO, "boot_verifier: Device is in RED boot state.\n");
+			break;
+	}
+}
+
+bool boot_verify_validate_keystore(unsigned char * user_addr)
+{
+	bool ret = false;
+	unsigned char *input = user_addr;
+	KEYSTORE *ks = NULL;
+	uint32_t len = read_der_message_length(input);
+	if(!len)
+	{
+		dprintf(CRITICAL, "boot_verifier: keystore length is invalid.\n");
+		return ret;
+	}
+
+	ks = d2i_KEYSTORE(NULL, (const unsigned char **)&input, len);
+	if(ks != NULL)
+	{
+		ret = true;
+	}
+	return ret;
+}
+
+static bool check_list(const char **list, const char* entry)
+{
+	if(list == NULL || entry == NULL)
+		return false;
+
+	while(*list != NULL)
+	{
+		if(!strcmp(entry, *list))
+			return true;
+
+		list++;
+	}
+
+	return false;
+}
diff --git a/platform/msm_shared/include/boot_verifier.h b/platform/msm_shared/include/boot_verifier.h
new file mode 100644
index 0000000..fe816ec
--- /dev/null
+++ b/platform/msm_shared/include/boot_verifier.h
@@ -0,0 +1,180 @@
+/*
+ * Copyright (c) 2014-2015, The Linux Foundation. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above
+ *    copyright notice, this list of conditions and the following
+ *    disclaimer in the documentation and/or other materials provided
+ *    with the distribution.
+ *  * Neither the name of The Linux Foundation nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+
+ * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+ * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
+ * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __BOOT_VERIFIER_H
+#define __BOOT_VERIFIER_H
+
+#include <asn1.h>
+#include <rsa.h>
+
+/**
+ *    AndroidVerifiedBootSignature DEFINITIONS ::=
+ *    BEGIN
+ *        FormatVersion ::= INTEGER
+ *        Certificate ::= Certificate
+ *        AlgorithmIdentifier ::=  SEQUENCE {
+ *            algorithm OBJECT IDENTIFIER,
+ *            parameters ANY DEFINED BY algorithm OPTIONAL
+ *        }
+ *        AuthenticatedAttributes ::= SEQUENCE {
+ *            target CHARACTER STRING,
+ *            length INTEGER
+ *        }
+ *        Signature ::= OCTET STRING
+ *     END
+ */
+
+typedef struct auth_attr_st
+{
+	ASN1_PRINTABLESTRING *target;
+	ASN1_INTEGER *len;
+}AUTH_ATTR;
+
+DECLARE_STACK_OF(AUTH_ATTR)
+DECLARE_ASN1_SET_OF(AUTH_ATTR)
+DECLARE_ASN1_FUNCTIONS(AUTH_ATTR)
+
+typedef struct verif_boot_sig_st
+{
+	ASN1_INTEGER *version;
+	X509 *certificate;
+	X509_ALGOR *algor;
+	AUTH_ATTR *auth_attr;
+	ASN1_OCTET_STRING *sig;
+}VERIFIED_BOOT_SIG;
+
+DECLARE_STACK_OF(VERIFIED_BOOT_SIG)
+DECLARE_ASN1_SET_OF(VERIFIED_BOOT_SIG)
+DECLARE_ASN1_FUNCTIONS(VERIFIED_BOOT_SIG)
+
+/**
+ * AndroidVerifiedBootKeystore DEFINITIONS ::=
+ * BEGIN
+ *     FormatVersion ::= INTEGER
+ *     KeyBag ::= SEQUENCE {
+ *         Key  ::= SEQUENCE {
+ *             AlgorithmIdentifier  ::=  SEQUENCE {
+ *                 algorithm OBJECT IDENTIFIER,
+ *                 parameters ANY DEFINED BY algorithm OPTIONAL
+ *             }
+ *             KeyMaterial ::= RSAPublicKey
+ *         }
+ *     }
+ *     Signature ::= AndroidVerifiedBootSignature
+ * END
+ */
+
+typedef struct key_st
+{
+	X509_ALGOR *algorithm_id;
+	RSA *key_material;
+}KEY;
+
+DECLARE_STACK_OF(KEY)
+DECLARE_ASN1_SET_OF(KEY)
+DECLARE_ASN1_FUNCTIONS(KEY)
+
+typedef struct keybag_st
+{
+	KEY *mykey;
+}KEYBAG;
+
+DECLARE_STACK_OF(KEYBAG)
+DECLARE_ASN1_SET_OF(KEYBAG)
+DECLARE_ASN1_FUNCTIONS(KEYBAG)
+
+typedef struct keystore_inner_st
+{
+	ASN1_INTEGER *version;
+	KEYBAG *mykeybag;
+}KEYSTORE_INNER;
+
+DECLARE_STACK_OF(KEYSTORE_INNER)
+DECLARE_ASN1_SET_OF(KEYSTORE_INNER)
+DECLARE_ASN1_FUNCTIONS(KEYSTORE_INNER)
+
+typedef struct keystore_st
+{
+	ASN1_INTEGER *version;
+	KEYBAG *mykeybag;
+	VERIFIED_BOOT_SIG *sig;
+}KEYSTORE;
+
+DECLARE_STACK_OF(KEYSTORE)
+DECLARE_ASN1_SET_OF(KEYSTORE)
+DECLARE_ASN1_FUNCTIONS(KEYSTORE)
+
+enum boot_state
+{
+	GREEN,
+	ORANGE,
+	YELLOW,
+	RED,
+};
+
+struct verified_boot_verity_mode
+{
+	bool verity_mode_enforcing;
+	char *name;
+};
+
+struct verified_boot_state_name
+{
+	uint32_t boot_state;
+	char *name;
+};
+
+enum boot_verfiy_event
+{
+	BOOT_INIT,
+	DEV_UNLOCK,
+	BOOTIMG_EMBEDDED_CERT_VERIFICATION_PASS,
+	BOOTIMG_KEYSTORE_VERIFICATION_PASS,
+	BOOTIMG_VERIFICATION_FAIL,
+	USER_DENIES,
+};
+
+extern char KEYSTORE_PTN_NAME[];
+/* Function to initialize keystore */
+uint32_t boot_verify_keystore_init();
+/* Function to verify boot/recovery image */
+bool boot_verify_image(unsigned char* img_addr, uint32_t img_size, char *pname);
+/* Function to send event to boot state machine */
+void boot_verify_send_event(uint32_t event);
+/* Read current boot state */
+uint32_t boot_verify_get_state();
+/* Print current boot state */
+void boot_verify_print_state();
+/* Function to validate keystore */
+bool boot_verify_validate_keystore(unsigned char * user_addr);
+/* Function to check if partition is allowed to flash in verified mode */
+bool boot_verify_flash_allowed(const char * entry);
+/* Function to send root of trust to trust zone */
+bool send_rot_command(uint32_t is_unlocked);
+#endif