| // Licensed to the Apache Software Foundation (ASF) under one |
| // or more contributor license agreements. See the NOTICE file |
| // distributed with this work for additional information |
| // regarding copyright ownership. The ASF licenses this file |
| // to you under the Apache License, Version 2.0 (the |
| // "License"); you may not use this file except in compliance |
| // with the License. You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, |
| // software distributed under the License is distributed on an |
| // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| // KIND, either express or implied. See the License for the |
| // specific language governing permissions and limitations |
| // under the License.. |
| |
| use sgx_tcrypto::*; |
| use sgx_types::*; |
| |
| pub const EC_LABEL_LENGTH: usize = 3; |
| pub const EC_SMK_LABEL: [u8; EC_LABEL_LENGTH] = [0x53, 0x4D, 0x4B]; |
| pub const EC_AEK_LABEL: [u8; EC_LABEL_LENGTH] = [0x41, 0x45, 0x4B]; |
| pub const EC_DERIVATION_BUFFER_SIZE: usize = 7; |
| |
| #[allow(clippy::trivially_copy_pass_by_ref)] |
| pub fn derive_key( |
| shared_key: &sgx_ec256_dh_shared_t, |
| label: &[u8; EC_LABEL_LENGTH], |
| ) -> SgxResult<sgx_align_key_128bit_t> { |
| let cmac_key = sgx_cmac_128bit_key_t::default(); |
| let mut key_derive_key = rsgx_rijndael128_cmac_msg(&cmac_key, shared_key).map_err(set_error)?; |
| |
| //derivation_buffer = counter(0x01) || label || 0x00 || output_key_len(0x0080) |
| let mut derivation_buffer = [0_u8; EC_DERIVATION_BUFFER_SIZE]; |
| derivation_buffer[0] = 0x01; |
| derivation_buffer[1] = label[0]; |
| derivation_buffer[2] = label[1]; |
| derivation_buffer[3] = label[2]; |
| derivation_buffer[4] = 0x00; |
| derivation_buffer[5] = 0x80; |
| derivation_buffer[6] = 0x00; |
| |
| let result = rsgx_rijndael128_align_cmac_slice(&key_derive_key, &derivation_buffer) |
| .map(|align_mac| { |
| let mut align_key = sgx_align_key_128bit_t::default(); |
| align_key.key = align_mac.mac; |
| align_key |
| }) |
| .map_err(set_error); |
| key_derive_key = Default::default(); |
| result |
| } |
| |
| fn set_error(sgx_ret: sgx_status_t) -> sgx_status_t { |
| match sgx_ret { |
| sgx_status_t::SGX_ERROR_OUT_OF_MEMORY => sgx_status_t::SGX_ERROR_OUT_OF_MEMORY, |
| _ => sgx_status_t::SGX_ERROR_UNEXPECTED, |
| } |
| } |