1 // 2 // Copyright (C) 2020 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 #pragma once 17 18 #include <optional> 19 // 20 #include <keymaster/soft_key_factory.h> 21 // 22 #include "host/commands/secure_env/tpm_resource_manager.h" 23 24 namespace cuttlefish { 25 26 /** 27 * Encrypts key data using a TPM-resident key and signs it with a TPM-resident 28 * key for privacy and integrity. 29 * 30 * This class is used to encrypt KeyMint data when it leaves the secure_env 31 * process, and is sent for storage to Android. When the data comes back, this 32 * class decrypts it again for use in Keymaster and other HAL API calls. 33 */ 34 class TpmKeyBlobMaker : public keymaster::SoftwareKeyBlobMaker { 35 public: 36 TpmKeyBlobMaker(TpmResourceManager& resource_manager); 37 38 keymaster_error_t CreateKeyBlob( 39 const keymaster::AuthorizationSet& key_description, 40 keymaster_key_origin_t origin, 41 const keymaster::KeymasterKeyBlob& key_material, 42 keymaster::KeymasterKeyBlob* blob, 43 keymaster::AuthorizationSet* hw_enforced, 44 keymaster::AuthorizationSet* sw_enforced) const override; 45 46 keymaster_error_t UnvalidatedCreateKeyBlob( 47 const keymaster::KeymasterKeyBlob& key_material, 48 const keymaster::AuthorizationSet& hw_enforced, 49 const keymaster::AuthorizationSet& sw_enforced, 50 const keymaster::AuthorizationSet& hidden, 51 keymaster::KeymasterKeyBlob* blob) const; 52 53 /** 54 * Intermediate function between KeymasterContext::ParseKeyBlob and 55 * KeyFactory::LoadKey, The inputs of this function match the outputs of 56 * KeymasterContext::ParseKeyBlob and the outputs of this function match the 57 * inputs of KeyFactory::LoadKey. 58 * 59 * KeymasterContext::ParseKeyBlob is the common entry point for decoding all 60 * keys, and is expected to delegate to a KeyFactory depending on the type of 61 * the serialized key. This method performs decryption operations shared 62 * between all TPM-Keymaster keys. 63 */ 64 keymaster_error_t UnwrapKeyBlob( 65 const keymaster_key_blob_t& blob, 66 keymaster::AuthorizationSet* hw_enforced, 67 keymaster::AuthorizationSet* sw_enforced, 68 const keymaster::AuthorizationSet& hidden, 69 keymaster::KeymasterKeyBlob* key_material) const; 70 71 keymaster_error_t SetSystemVersion(uint32_t os_version, uint32_t os_patchlevel); 72 keymaster_error_t SetVendorPatchlevel(uint32_t vendor_patchlevel); 73 keymaster_error_t SetBootPatchlevel(uint32_t boot_patchlevel); 74 75 private: 76 TpmResourceManager& resource_manager_; 77 uint32_t os_version_; 78 uint32_t os_patchlevel_; 79 std::optional<uint32_t> vendor_patchlevel_; 80 std::optional<uint32_t> boot_patchlevel_; 81 }; 82 83 } // namespace cuttlefish 84