/* Populates private/public key pair - caller code allocates memory * Parameters: * Return: sgx_status_t - SGX_SUCCESS or failure as defined sgx_error.h * Inputs: sgx_ecc_state_handle_t ecc_handle - Handle to ECC crypto system * Outputs: sgx_ec256_private_t *p_private - Pointer to the private key * sgx_ec256_public_t *p_public - Pointer to the public key */ sgx_status_t sgx_ecc256_create_key_pair(sgx_ec256_private_t *p_private, sgx_ec256_public_t *p_public, sgx_ecc_state_handle_t ecc_handle) { if ((ecc_handle == NULL) || (p_private == NULL) || (p_public == NULL)) { return SGX_ERROR_INVALID_PARAMETER; } IppsBigNumState* dh_priv_BN = NULL; IppsECCPPointState* point_pub = NULL; IppsBigNumState* pub_gx = NULL; IppsBigNumState* pub_gy = NULL; IppStatus ipp_ret = ippStsNoErr; int ecPointSize = 0; IppsECCPState* p_ecc_state = (IppsECCPState*)ecc_handle; do { //init eccp point ipp_ret = ippsECCPPointGetSize(256, &ecPointSize); ERROR_BREAK(ipp_ret); point_pub = (IppsECCPPointState*)(malloc(ecPointSize)); if (!point_pub) { ipp_ret = ippStsNoMemErr; break; } ipp_ret = ippsECCPPointInit(256, point_pub); ERROR_BREAK(ipp_ret); ipp_ret = sgx_ipp_newBN(NULL, SGX_ECP256_KEY_SIZE, &dh_priv_BN); ERROR_BREAK(ipp_ret); // Use the true random number (DRNG) // Notice that IPP ensures the private key generated is non-zero ipp_ret = ippsECCPGenKeyPair(dh_priv_BN, point_pub, p_ecc_state, (IppBitSupplier)sgx_ipp_DRNGen, NULL); ERROR_BREAK(ipp_ret); //convert point_result to oct string ipp_ret = sgx_ipp_newBN(NULL, SGX_ECP256_KEY_SIZE, &pub_gx); ERROR_BREAK(ipp_ret); ipp_ret = sgx_ipp_newBN(NULL, SGX_ECP256_KEY_SIZE, &pub_gy); ERROR_BREAK(ipp_ret); ipp_ret = ippsECCPGetPoint(pub_gx, pub_gy, point_pub, p_ecc_state); ERROR_BREAK(ipp_ret); IppsBigNumSGN sgn = IppsBigNumPOS; Ipp32u *pdata = NULL; // ippsRef_BN is in bits not bytes (versus old ippsGet_BN) int length = 0; ipp_ret = ippsRef_BN(&sgn, &length, &pdata, pub_gx); ERROR_BREAK(ipp_ret); memset(p_public->gx, 0, sizeof(p_public->gx)); ipp_ret = check_copy_size(sizeof(p_public->gx), ROUND_TO(length, 8) / 8); ERROR_BREAK(ipp_ret); memcpy(p_public->gx, pdata, ROUND_TO(length, 8) / 8); ipp_ret = ippsRef_BN(&sgn, &length, &pdata, pub_gy); ERROR_BREAK(ipp_ret); memset(p_public->gy, 0, sizeof(p_public->gy)); ipp_ret = check_copy_size(sizeof(p_public->gy), ROUND_TO(length, 8) / 8); ERROR_BREAK(ipp_ret); memcpy(p_public->gy, pdata, ROUND_TO(length, 8) / 8); ipp_ret = ippsRef_BN(&sgn, &length, &pdata, dh_priv_BN); ERROR_BREAK(ipp_ret); memset(p_private->r, 0, sizeof(p_private->r)); ipp_ret = check_copy_size(sizeof(p_private->r), ROUND_TO(length, 8) / 8); ERROR_BREAK(ipp_ret); memcpy(p_private->r, pdata, ROUND_TO(length, 8) / 8); } while (0); //Clear temp buffer before free. if (point_pub) memset_s(point_pub, ecPointSize, 0, ecPointSize); SAFE_FREE(point_pub); sgx_ipp_secure_free_BN(pub_gx, SGX_ECP256_KEY_SIZE); sgx_ipp_secure_free_BN(pub_gy, SGX_ECP256_KEY_SIZE); sgx_ipp_secure_free_BN(dh_priv_BN, SGX_ECP256_KEY_SIZE); switch (ipp_ret) { case ippStsNoErr: return SGX_SUCCESS; case ippStsNoMemErr: case ippStsMemAllocErr: return SGX_ERROR_OUT_OF_MEMORY; case ippStsNullPtrErr: case ippStsLengthErr: case ippStsOutOfRangeErr: case ippStsSizeErr: case ippStsBadArgErr: return SGX_ERROR_INVALID_PARAMETER; default: return SGX_ERROR_UNEXPECTED; } }
/** Create an ECC public key based on a given ECC private key. * * Parameters: * Return: sgx_status_t - SGX_SUCCESS or failure as defined in sgx_error.h * Input: p_att_priv_key - Input private key * Output: p_att_pub_key - Output public key - LITTLE ENDIAN * */ sgx_status_t sgx_ecc256_calculate_pub_from_priv(const sgx_ec256_private_t *p_att_priv_key, sgx_ec256_public_t *p_att_pub_key) { if ((p_att_priv_key == NULL) || (p_att_pub_key == NULL)) { return SGX_ERROR_INVALID_PARAMETER; } IppsECCPState* p_ecc_state = NULL; sgx_status_t ret = SGX_ERROR_UNEXPECTED; int ctx_size = 0; int point_size = 0; IppsECCPPointState* public_key = NULL; IppsBigNumState* bn_o = NULL; IppsBigNumState* bn_x = NULL; IppsBigNumState* bn_y = NULL; sgx_ec256_private_t att_priv_key_be; uint8_t* p_temp; int size = 0; IppsBigNumSGN sgn; do { //get the size of the IppsECCPState context // if (ippsECCPGetSize(ECC_FIELD_SIZE, &ctx_size) != ippStsNoErr) { break; } //allocate ecc ctx // p_ecc_state = (IppsECCPState*)(malloc(ctx_size)); if (NULL == p_ecc_state) { ret = SGX_ERROR_OUT_OF_MEMORY; break; } //init ecc ctx // if (ippsECCPInit(ECC_FIELD_SIZE, p_ecc_state) != ippStsNoErr) { break; } //set up elliptic curve domain parameters over GF(p) // if (ippsECCPSetStd(IppECCPStd256r1, p_ecc_state) != ippStsNoErr) { break; } //get point (public key) size // if (ippsECCPPointGetSize(ECC_FIELD_SIZE, &point_size) != ippStsNoErr) { break; } //allocate point of point_size size // public_key = (IppsECCPPointState*)(malloc(point_size)); if (NULL == public_key) { ret = SGX_ERROR_OUT_OF_MEMORY; break; } //init point // if (ippsECCPPointInit(ECC_FIELD_SIZE, public_key) != ippStsNoErr) { break; } //allocate bn_o, will be used for private key // if (sgx_ipp_newBN(NULL, sizeof(sgx_ec256_private_t), &bn_o) != ippStsNoErr) { break; } //convert private key into big endian // p_temp = (uint8_t*)p_att_priv_key; for (uint32_t i = 0; i<sizeof(att_priv_key_be); i++) { att_priv_key_be.r[i] = *(p_temp + sizeof(att_priv_key_be) - 1 - i); } //assign private key into bn_o // if (ippsSetOctString_BN(reinterpret_cast<Ipp8u *>(&att_priv_key_be), sizeof(sgx_ec256_private_t), bn_o) != ippStsNoErr) { break; } //compute public key from the given private key (bn_o) of the elliptic cryptosystem (p_ecc_state) over GF(p). // if (ippsECCPPublicKey(bn_o, public_key, p_ecc_state) != ippStsNoErr) { break; } //allocate BNs // if (sgx_ipp_newBN(NULL, sizeof(sgx_ec256_private_t), &bn_x) != ippStsNoErr) { break; } if (sgx_ipp_newBN(NULL, sizeof(sgx_ec256_private_t), &bn_y) != ippStsNoErr) { break; } //assign public key into BNs // if (ippsECCPGetPoint(bn_x, bn_y, public_key, p_ecc_state) != ippStsNoErr) { break; } //output key in little endian order // //gx value if (ippsGetSize_BN(bn_x, &size) != ippStsNoErr) { break; } if (ippsGet_BN(&sgn, &size, reinterpret_cast<Ipp32u *>(p_att_pub_key->gx), bn_x) != ippStsNoErr) { break; } //gy value // if (ippsGetSize_BN(bn_y, &size) != ippStsNoErr) { break; } if (ippsGet_BN(&sgn, &size, reinterpret_cast<Ipp32u *>(p_att_pub_key->gy), bn_y) != ippStsNoErr) { break; } ret = SGX_SUCCESS; } while (0); //in case of failure clear public key // if (ret != SGX_SUCCESS) { (void)memset_s(p_att_pub_key, sizeof(sgx_ec256_public_t), 0, sizeof(sgx_ec256_public_t)); } CLEAR_FREE_MEM(p_ecc_state, ctx_size); CLEAR_FREE_MEM(public_key, point_size); sgx_ipp_secure_free_BN(bn_o, sizeof(sgx_ec256_private_t)); sgx_ipp_secure_free_BN(bn_x, sizeof(sgx_ec256_private_t)); sgx_ipp_secure_free_BN(bn_y, sizeof(sgx_ec256_private_t)); return ret; }