/** * Copyright (c) 2018 - 2020, Nordic Semiconductor ASA * * All rights reserved. * * Redistribution and use in source and binary forms, with or without modification, * are permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * 2. Redistributions in binary form, except as embedded into a Nordic * Semiconductor ASA integrated circuit in a product or a software update for * such product, 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. * * 3. Neither the name of Nordic Semiconductor ASA nor the names of its * contributors may be used to endorse or promote products derived from this * software without specific prior written permission. * * 4. This software, with or without modification, must only be used with a * Nordic Semiconductor ASA integrated circuit. * * 5. Any software provided in binary form under this license must not be reverse * engineered, decompiled, modified and/or disassembled. * * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA 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 "sdk_config.h" #include "nordic_common.h" #if NRF_MODULE_ENABLED(NRF_CRYPTO) && NRF_MODULE_ENABLED(NRF_CRYPTO_BACKEND_OPTIGA) #include #include #include "nrf_crypto_ecc.h" #include "nrf_crypto_ecdh.h" #include "nrf_crypto_mem.h" #include "nrf_crypto_rng.h" #include "nrf_crypto_shared.h" #include "nrf_assert.h" #include "optiga_backend_ecc.h" /*lint -save -e????*/ #include "optiga/optiga_crypt.h" /*lint -restore*/ int nrf_crypto_backend_optiga_ecc_optiga_rng(void * p_param, unsigned char * p_data, size_t size) { #if NRF_MODULE_ENABLED(NRF_CRYPTO_RNG) return NRF_SUCCESS; #else return NRF_ERROR_CRYPTO_FEATURE_UNAVAILABLE; #endif } static const uint8_t der_pub_key_header[] = { 0x03, // ASN.1 BITSTRING 0x42, // bytes following 0x00, // no unused bits 0x04 // uncompressed key, see https://tools.ietf.org/html/rfc5480#section-2.2 }; #define DER_PUB_KEY_HEADER_LEN (sizeof(der_pub_key_header)/sizeof(der_pub_key_header[0])) // for our purposes we always have 1 byte tag + 1 byte length #define DER_OCTET_STRING_HEADER_LEN 2 // lengths for the ASN.1 DER encoded keys imported and exported by OPTIGA #define OPTIGA_SECP256R1_PRIV_KEY_LEN (DER_OCTET_STRING_HEADER_LEN + NRF_CRYPTO_ECC_SECP256R1_RAW_PRIVATE_KEY_SIZE) #define OPTIGA_SECP256R1_PUBL_KEY_LEN (DER_PUB_KEY_HEADER_LEN + NRF_CRYPTO_ECC_SECP256R1_RAW_PUBLIC_KEY_SIZE) ret_code_t nrf_crypto_backend_optiga_key_pair_generate( void * p_context, void * p_private_key, void * p_public_key) { optiga_lib_status_t res = OPTIGA_LIB_ERROR; nrf_crypto_backend_secp256r1_public_key_t * p_pub = (nrf_crypto_backend_secp256r1_public_key_t *) p_public_key; nrf_crypto_backend_secp256r1_private_key_t * p_priv = (nrf_crypto_backend_secp256r1_private_key_t *) p_private_key; bool export_private_key; if (p_priv->oid == 0) { // OID=0 was implicitly specified when initializising, mostly due to Nordic internal code calling our API p_priv->oid = (optiga_key_id_t)0xE100; export_private_key = false; } else if (p_priv->oid == NRF_CRYPTO_INFINEON_PRIVKEY_HOST_OID) { export_private_key = true; } else // any other value for OID, we assume the OID was purposefully specified by caller { export_private_key = false; } void * priv_key; if (export_private_key) { //lint -save -e611 -e545 (Suspicious cast, Suspicious use of &) priv_key = (void*) &p_priv->raw_privkey; //lint -restore p_priv->oid = (optiga_key_id_t)NRF_CRYPTO_INFINEON_PRIVKEY_HOST_OID; } else { //lint -save -e611 -e545 (Suspicious cast, Suspicious use of &) priv_key = (void*) &p_priv->oid; memset(p_priv->raw_privkey, 0, OPTIGA_SECP256R1_PRIV_KEY_LEN); //lint -restore } // Set all flags because the nrf_crypto API does not allow to specify key use const optiga_key_usage_t key_usage = (optiga_key_usage_t)(OPTIGA_KEY_USAGE_AUTHENTICATION | OPTIGA_KEY_USAGE_SIGN | OPTIGA_KEY_USAGE_KEY_AGREEMENT); uint16_t publ_key_len = OPTIGA_SECP256R1_PUBL_KEY_LEN; res = optiga_crypt_ecc_generate_keypair(OPTIGA_ECC_NIST_P_256, key_usage, export_private_key, priv_key, p_pub->raw_pubkey, &publ_key_len); if(res != OPTIGA_LIB_SUCCESS) { // error in the optiga library return NRF_ERROR_CRYPTO_INTERNAL; } if(publ_key_len != OPTIGA_SECP256R1_PUBL_KEY_LEN) { // unexpected length return NRF_ERROR_CRYPTO_INTERNAL; } // mark the public key as stored in host memory p_pub->oid = (optiga_key_id_t)NRF_CRYPTO_INFINEON_PUBKEY_HOST_OID; return NRF_SUCCESS; } ret_code_t nrf_crypto_backend_optiga_public_key_calculate( void * p_context, void const * p_private_key, void * p_public_key) { return NRF_ERROR_CRYPTO_FEATURE_UNAVAILABLE; } ret_code_t nrf_crypto_backend_optiga_private_key_from_raw( void * p_private_key, uint8_t const * p_raw_data) { return NRF_ERROR_CRYPTO_FEATURE_UNAVAILABLE; } #define DER_TAG_OCTET_STRING 0x04 ret_code_t nrf_crypto_backend_optiga_private_key_to_raw( void const * p_private_key, uint8_t * p_raw_data) { nrf_crypto_backend_secp256r1_private_key_t * p_priv = (nrf_crypto_backend_secp256r1_private_key_t *)p_private_key; nrf_crypto_ecc_curve_info_t const * p_info = p_priv->header.p_info; if(p_priv->oid != NRF_CRYPTO_INFINEON_PRIVKEY_HOST_OID) { // must use magic OID for private key exported to host return NRF_ERROR_CRYPTO_INTERNAL; } uint8_t* p_key = p_priv->raw_privkey; if(*p_key != DER_TAG_OCTET_STRING) { // private key must be encoded as DER OCTET STRING return NRF_ERROR_CRYPTO_INTERNAL; } p_key++; if(p_info == &g_nrf_crypto_ecc_secp256r1_curve_info) { if(*p_key != NRF_CRYPTO_ECC_SECP256R1_RAW_PRIVATE_KEY_SIZE) { // wrong length return NRF_ERROR_CRYPTO_INTERNAL; } p_key++; memcpy(p_raw_data, p_key, NRF_CRYPTO_ECC_SECP256R1_RAW_PRIVATE_KEY_SIZE); return NRF_SUCCESS; } return NRF_ERROR_CRYPTO_FEATURE_UNAVAILABLE; } ret_code_t nrf_crypto_backend_optiga_public_key_from_raw( void * p_public_key, uint8_t const * p_raw_data) { nrf_crypto_backend_secp256r1_public_key_t * p_pub = (nrf_crypto_backend_secp256r1_public_key_t *)p_public_key; nrf_crypto_ecc_curve_info_t const * p_info = p_pub->header.p_info; if (p_info == &g_nrf_crypto_ecc_secp256r1_curve_info) { // copy header memcpy(p_pub->raw_pubkey, der_pub_key_header, DER_PUB_KEY_HEADER_LEN); // copy public key data memcpy(p_pub->raw_pubkey + DER_PUB_KEY_HEADER_LEN, p_raw_data, NRF_CRYPTO_ECC_SECP256R1_RAW_PUBLIC_KEY_SIZE); // Set OID to magic number for host-supplied public key p_pub->oid = (optiga_key_id_t)NRF_CRYPTO_INFINEON_PUBKEY_HOST_OID; return NRF_SUCCESS; } return NRF_ERROR_CRYPTO_FEATURE_UNAVAILABLE; } ret_code_t nrf_crypto_backend_optiga_public_key_to_raw( void const * p_public_key, uint8_t * p_raw_data) { nrf_crypto_backend_secp256r1_public_key_t * p_pub = (nrf_crypto_backend_secp256r1_public_key_t *)p_public_key; nrf_crypto_ecc_curve_info_t const * p_info = p_pub->header.p_info; if(p_pub->oid != NRF_CRYPTO_INFINEON_PUBKEY_HOST_OID) { // must use magic OID for host supplied public key return NRF_ERROR_CRYPTO_INTERNAL; } if (p_info == &g_nrf_crypto_ecc_secp256r1_curve_info) { if(memcmp(p_pub->raw_pubkey, der_pub_key_header, DER_PUB_KEY_HEADER_LEN) != 0) { // public key not correctly encoded return NRF_ERROR_CRYPTO_INTERNAL; } memcpy(p_raw_data, p_pub->raw_pubkey + DER_PUB_KEY_HEADER_LEN, NRF_CRYPTO_ECC_SECP256R1_RAW_PUBLIC_KEY_SIZE); return NRF_SUCCESS; } return NRF_ERROR_CRYPTO_FEATURE_UNAVAILABLE; } ret_code_t nrf_crypto_backend_optiga_private_key_free( void * p_private_key) { return NRF_ERROR_CRYPTO_INTERNAL; } ret_code_t nrf_crypto_backend_optiga_public_key_free( void * p_public_key) { return NRF_ERROR_CRYPTO_INTERNAL; } #if NRF_MODULE_ENABLED(NRF_CRYPTO_BACKEND_OPTIGA_ECC_SECP256R1) const nrf_crypto_ecc_curve_info_t g_nrf_crypto_ecc_secp256r1_curve_info = { .public_key_size = sizeof(nrf_crypto_backend_secp256r1_public_key_t), .private_key_size = sizeof(nrf_crypto_backend_optiga_ecc_private_key_t), .curve_type = NRF_CRYPTO_ECC_SECP256R1_CURVE_TYPE, .raw_private_key_size = NRF_CRYPTO_ECC_SECP256R1_RAW_PRIVATE_KEY_SIZE, .raw_public_key_size = NRF_CRYPTO_ECC_SECP256R1_RAW_PUBLIC_KEY_SIZE, .p_backend_data = (void *)OPTIGA_ECC_NIST_P_256, }; #endif #endif // NRF_MODULE_ENABLED(NRF_CRYPTO) && NRF_MODULE_ENABLED(NRF_CRYPTO_BACKEND_OPTIGA)