1 /* 2 * Copyright 2015 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include "openssl_utils.h" 18 19 #include <keymaster/android_keymaster_utils.h> 20 21 #include "openssl_err.h" 22 23 namespace keymaster { 24 25 static int convert_to_evp(keymaster_algorithm_t algorithm) { 26 switch (algorithm) { 27 case KM_ALGORITHM_RSA: 28 return EVP_PKEY_RSA; 29 case KM_ALGORITHM_EC: 30 return EVP_PKEY_EC; 31 default: 32 return -1; 33 }; 34 } 35 36 keymaster_error_t convert_pkcs8_blob_to_evp(const uint8_t* key_data, size_t key_length, 37 keymaster_algorithm_t expected_algorithm, 38 UniquePtr<EVP_PKEY, EVP_PKEY_Delete>* pkey) { 39 if (key_data == NULL || key_length <= 0) 40 return KM_ERROR_INVALID_KEY_BLOB; 41 42 UniquePtr<PKCS8_PRIV_KEY_INFO, PKCS8_PRIV_KEY_INFO_Delete> pkcs8( 43 d2i_PKCS8_PRIV_KEY_INFO(NULL, &key_data, key_length)); 44 if (pkcs8.get() == NULL) 45 return TranslateLastOpenSslError(true /* log_message */); 46 47 pkey->reset(EVP_PKCS82PKEY(pkcs8.get())); 48 if (!pkey->get()) 49 return TranslateLastOpenSslError(true /* log_message */); 50 51 if (EVP_PKEY_type((*pkey)->type) != convert_to_evp(expected_algorithm)) { 52 LOG_E("EVP key algorithm was %d, not the expected %d", EVP_PKEY_type((*pkey)->type), 53 convert_to_evp(expected_algorithm)); 54 return KM_ERROR_INVALID_KEY_BLOB; 55 } 56 57 return KM_ERROR_OK; 58 } 59 60 keymaster_error_t KeyMaterialToEvpKey(keymaster_key_format_t key_format, 61 const KeymasterKeyBlob& key_material, 62 keymaster_algorithm_t expected_algorithm, 63 UniquePtr<EVP_PKEY, EVP_PKEY_Delete>* pkey) { 64 if (key_format != KM_KEY_FORMAT_PKCS8) 65 return KM_ERROR_UNSUPPORTED_KEY_FORMAT; 66 67 return convert_pkcs8_blob_to_evp(key_material.key_material, key_material.key_material_size, 68 expected_algorithm, pkey); 69 } 70 71 keymaster_error_t EvpKeyToKeyMaterial(const EVP_PKEY* pkey, KeymasterKeyBlob* key_blob) { 72 int key_data_size = i2d_PrivateKey(pkey, NULL /* key_data*/); 73 if (key_data_size <= 0) 74 return TranslateLastOpenSslError(); 75 76 if (!key_blob->Reset(key_data_size)) 77 return KM_ERROR_MEMORY_ALLOCATION_FAILED; 78 79 uint8_t* tmp = key_blob->writable_data(); 80 i2d_PrivateKey(pkey, &tmp); 81 82 return KM_ERROR_OK; 83 } 84 85 } // namespace keymaster 86
