| /* |
| * Copyright 2015 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 "auth_encrypted_key_blob.h" |
| |
| #include <keymaster/android_keymaster_utils.h> |
| #include <keymaster/authorization_set.h> |
| #include <keymaster/logger.h> |
| |
| #include "ocb_utils.h" |
| |
| namespace keymaster { |
| |
| const uint32_t CURRENT_BLOB_VERSION = 0; |
| |
| keymaster_error_t SerializeAuthEncryptedBlob(const KeymasterKeyBlob& encrypted_key_material, |
| const AuthorizationSet& hw_enforced, |
| const AuthorizationSet& sw_enforced, |
| |
| const Buffer& nonce, const Buffer& tag, |
| KeymasterKeyBlob* key_blob) { |
| size_t size = 1 /* version byte */ + nonce.SerializedSize() + |
| encrypted_key_material.SerializedSize() + tag.SerializedSize() + |
| hw_enforced.SerializedSize() + sw_enforced.SerializedSize(); |
| |
| if (!key_blob->Reset(size)) |
| return KM_ERROR_MEMORY_ALLOCATION_FAILED; |
| |
| uint8_t* buf = key_blob->writable_data(); |
| const uint8_t* end = key_blob->key_material + key_blob->key_material_size; |
| |
| *buf++ = CURRENT_BLOB_VERSION; |
| buf = nonce.Serialize(buf, end); |
| buf = encrypted_key_material.Serialize(buf, end); |
| buf = tag.Serialize(buf, end); |
| buf = hw_enforced.Serialize(buf, end); |
| buf = sw_enforced.Serialize(buf, end); |
| if (buf != key_blob->key_material + key_blob->key_material_size) |
| return KM_ERROR_UNKNOWN_ERROR; |
| |
| return KM_ERROR_OK; |
| } |
| |
| keymaster_error_t DeserializeAuthEncryptedBlob(const KeymasterKeyBlob& key_blob, |
| KeymasterKeyBlob* encrypted_key_material, |
| AuthorizationSet* hw_enforced, |
| AuthorizationSet* sw_enforced, Buffer* nonce, |
| Buffer* tag) { |
| const uint8_t* tmp = key_blob.key_material; |
| const uint8_t** buf_ptr = &tmp; |
| const uint8_t* end = tmp + key_blob.key_material_size; |
| |
| uint8_t version = *(*buf_ptr)++; |
| if (version != CURRENT_BLOB_VERSION || // |
| !nonce->Deserialize(buf_ptr, end) || nonce->available_read() != OCB_NONCE_LENGTH || |
| !encrypted_key_material->Deserialize(buf_ptr, end) || // |
| !tag->Deserialize(buf_ptr, end) || tag->available_read() != OCB_TAG_LENGTH || |
| !hw_enforced->Deserialize(buf_ptr, end) || // |
| !sw_enforced->Deserialize(buf_ptr, end)) |
| return KM_ERROR_INVALID_KEY_BLOB; |
| return KM_ERROR_OK; |
| } |
| |
| } // namespace keymaster |