| /* |
| * Copyright 2014 The Android Open Source Project |
| * |
| * Licensed 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. |
| */ |
| |
| #include <keymaster/km_openssl/hmac_key.h> |
| |
| #include <openssl/err.h> |
| #include <openssl/rand.h> |
| |
| #include "hmac_operation.h" |
| |
| namespace keymaster { |
| |
| static HmacSignOperationFactory sign_factory; |
| static HmacVerifyOperationFactory verify_factory; |
| |
| OperationFactory* HmacKeyFactory::GetOperationFactory(keymaster_purpose_t purpose) const { |
| switch (purpose) { |
| case KM_PURPOSE_SIGN: |
| return &sign_factory; |
| case KM_PURPOSE_VERIFY: |
| return &verify_factory; |
| default: |
| return nullptr; |
| } |
| } |
| |
| keymaster_error_t HmacKeyFactory::LoadKey(KeymasterKeyBlob&& key_material, |
| const AuthorizationSet& /* additional_params */, |
| AuthorizationSet&& hw_enforced, |
| AuthorizationSet&& sw_enforced, |
| UniquePtr<Key>* key) const { |
| if (!key) return KM_ERROR_OUTPUT_PARAMETER_NULL; |
| |
| uint32_t min_mac_length; |
| if (!hw_enforced.GetTagValue(TAG_MIN_MAC_LENGTH, &min_mac_length) && |
| !sw_enforced.GetTagValue(TAG_MIN_MAC_LENGTH, &min_mac_length)) { |
| LOG_E("HMAC key must have KM_TAG_MIN_MAC_LENGTH", 0); |
| return KM_ERROR_INVALID_KEY_BLOB; |
| } |
| |
| key->reset(new (std::nothrow) |
| HmacKey(move(key_material), move(hw_enforced), move(sw_enforced), this)); |
| if (!key->get()) return KM_ERROR_MEMORY_ALLOCATION_FAILED; |
| return KM_ERROR_OK; |
| } |
| |
| keymaster_error_t HmacKeyFactory::validate_algorithm_specific_new_key_params( |
| const AuthorizationSet& key_description) const { |
| uint32_t min_mac_length_bits; |
| if (!key_description.GetTagValue(TAG_MIN_MAC_LENGTH, &min_mac_length_bits)) |
| return KM_ERROR_MISSING_MIN_MAC_LENGTH; |
| |
| keymaster_digest_t digest; |
| if (!key_description.GetTagValue(TAG_DIGEST, &digest)) { |
| LOG_E("%d digests specified for HMAC key", key_description.GetTagCount(TAG_DIGEST)); |
| return KM_ERROR_UNSUPPORTED_DIGEST; |
| } |
| |
| size_t hash_size_bits = 0; |
| switch (digest) { |
| case KM_DIGEST_NONE: |
| return KM_ERROR_UNSUPPORTED_DIGEST; |
| case KM_DIGEST_MD5: |
| hash_size_bits = 128; |
| break; |
| case KM_DIGEST_SHA1: |
| hash_size_bits = 160; |
| break; |
| case KM_DIGEST_SHA_2_224: |
| hash_size_bits = 224; |
| break; |
| case KM_DIGEST_SHA_2_256: |
| hash_size_bits = 256; |
| break; |
| case KM_DIGEST_SHA_2_384: |
| hash_size_bits = 384; |
| break; |
| case KM_DIGEST_SHA_2_512: |
| hash_size_bits = 512; |
| break; |
| }; |
| |
| if (hash_size_bits == 0) { |
| // digest was not matched |
| return KM_ERROR_UNSUPPORTED_DIGEST; |
| } |
| |
| if (min_mac_length_bits % 8 != 0 || min_mac_length_bits > hash_size_bits) |
| return KM_ERROR_UNSUPPORTED_MIN_MAC_LENGTH; |
| |
| if (min_mac_length_bits < kMinHmacLengthBits) return KM_ERROR_UNSUPPORTED_MIN_MAC_LENGTH; |
| |
| return KM_ERROR_OK; |
| } |
| |
| } // namespace keymaster |