1 /*
2 * Copyright (C) 2021 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 "AndroidRemotelyProvisionedComponentDevice.h"
18
19 #include <assert.h>
20 #include <variant>
21
22 #include <cppbor.h>
23 #include <cppbor_parse.h>
24
25 #include <KeyMintUtils.h>
26 #include <keymaster/cppcose/cppcose.h>
27 #include <keymaster/keymaster_configuration.h>
28
29 #include <openssl/bn.h>
30 #include <openssl/ec.h>
31 #include <openssl/rand.h>
32 #include <openssl/x509.h>
33
34 namespace aidl::android::hardware::security::keymint {
35
36 using keymaster::GenerateCsrRequest;
37 using keymaster::GenerateCsrResponse;
38 using keymaster::GenerateRkpKeyRequest;
39 using keymaster::GenerateRkpKeyResponse;
40 using keymaster::KeymasterBlob;
41 using ::std::string;
42 using ::std::unique_ptr;
43 using ::std::vector;
44 using bytevec = ::std::vector<uint8_t>;
45
46 namespace {
47
48 constexpr auto STATUS_FAILED = IRemotelyProvisionedComponent::STATUS_FAILED;
49
50 struct AStatusDeleter {
operator ()aidl::android::hardware::security::keymint::__anon6e7f3adf0111::AStatusDeleter51 void operator()(AStatus* p) { AStatus_delete(p); }
52 };
53
54 class Status {
55 public:
Status()56 Status() : status_(AStatus_newOk()) {}
Status(int32_t errCode,const std::string & errMsg)57 Status(int32_t errCode, const std::string& errMsg)
58 : status_(AStatus_fromServiceSpecificErrorWithMessage(errCode, errMsg.c_str())) {}
Status(const std::string & errMsg)59 explicit Status(const std::string& errMsg)
60 : status_(AStatus_fromServiceSpecificErrorWithMessage(STATUS_FAILED, errMsg.c_str())) {}
Status(AStatus * status)61 explicit Status(AStatus* status) : status_(status ? status : AStatus_newOk()) {}
62
63 Status(Status&&) = default;
64 Status(const Status&) = delete;
65
operator ::ndk::ScopedAStatus()66 operator ::ndk::ScopedAStatus() && { // NOLINT(google-explicit-constructor)
67 return ndk::ScopedAStatus(status_.release());
68 }
69
isOk() const70 bool isOk() const { return AStatus_isOk(status_.get()); }
71
getMessage() const72 const char* getMessage() const { return AStatus_getMessage(status_.get()); }
73
74 private:
75 std::unique_ptr<AStatus, AStatusDeleter> status_;
76 };
77
78 } // namespace
79
AndroidRemotelyProvisionedComponentDevice(const std::shared_ptr<AndroidKeyMintDevice> & keymint)80 AndroidRemotelyProvisionedComponentDevice::AndroidRemotelyProvisionedComponentDevice(
81 const std::shared_ptr<AndroidKeyMintDevice>& keymint) {
82 impl_ = keymint->getKeymasterImpl();
83 }
84
getHardwareInfo(RpcHardwareInfo * info)85 ScopedAStatus AndroidRemotelyProvisionedComponentDevice::getHardwareInfo(RpcHardwareInfo* info) {
86 info->versionNumber = 2;
87 info->rpcAuthorName = "Google";
88 info->supportedEekCurve = RpcHardwareInfo::CURVE_25519;
89 info->uniqueId = "default keymint";
90 return ScopedAStatus::ok();
91 }
92
generateEcdsaP256KeyPair(bool testMode,MacedPublicKey * macedPublicKey,bytevec * privateKeyHandle)93 ScopedAStatus AndroidRemotelyProvisionedComponentDevice::generateEcdsaP256KeyPair(
94 bool testMode, MacedPublicKey* macedPublicKey, bytevec* privateKeyHandle) {
95 GenerateRkpKeyRequest request(impl_->message_version());
96 request.test_mode = testMode;
97 GenerateRkpKeyResponse response(impl_->message_version());
98 impl_->GenerateRkpKey(request, &response);
99 if (response.error != KM_ERROR_OK) {
100 return Status(-static_cast<int32_t>(response.error), "Failure in key generation.");
101 }
102
103 macedPublicKey->macedKey = km_utils::kmBlob2vector(response.maced_public_key);
104 *privateKeyHandle = km_utils::kmBlob2vector(response.key_blob);
105 return ScopedAStatus::ok();
106 }
107
generateCertificateRequest(bool testMode,const vector<MacedPublicKey> & keysToSign,const bytevec & endpointEncCertChain,const bytevec & challenge,DeviceInfo * deviceInfo,ProtectedData * protectedData,bytevec * keysToSignMac)108 ScopedAStatus AndroidRemotelyProvisionedComponentDevice::generateCertificateRequest(
109 bool testMode, const vector<MacedPublicKey>& keysToSign, const bytevec& endpointEncCertChain,
110 const bytevec& challenge, DeviceInfo* deviceInfo, ProtectedData* protectedData,
111 bytevec* keysToSignMac) {
112 GenerateCsrRequest request(impl_->message_version());
113 request.test_mode = testMode;
114 request.num_keys = keysToSign.size();
115 request.keys_to_sign_array = new (std::nothrow) KeymasterBlob[keysToSign.size()];
116 if (request.keys_to_sign_array == nullptr) {
117 return km_utils::kmError2ScopedAStatus(KM_ERROR_MEMORY_ALLOCATION_FAILED);
118 }
119 for (size_t i = 0; i < keysToSign.size(); i++) {
120 request.SetKeyToSign(i, keysToSign[i].macedKey.data(), keysToSign[i].macedKey.size());
121 }
122 request.SetEndpointEncCertChain(endpointEncCertChain.data(), endpointEncCertChain.size());
123 request.SetChallenge(challenge.data(), challenge.size());
124 GenerateCsrResponse response(impl_->message_version());
125 impl_->GenerateCsr(request, &response);
126
127 if (response.error != KM_ERROR_OK) {
128 return Status(-static_cast<int32_t>(response.error), "Failure in CSR Generation.");
129 }
130 deviceInfo->deviceInfo = km_utils::kmBlob2vector(response.device_info_blob);
131 protectedData->protectedData = km_utils::kmBlob2vector(response.protected_data_blob);
132 *keysToSignMac = km_utils::kmBlob2vector(response.keys_to_sign_mac);
133 return ScopedAStatus::ok();
134 }
135
136 } // namespace aidl::android::hardware::security::keymint
137