1 // Copyright 2015 The Android Open Source Project
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 //      http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 
15 #ifndef KEYSTORE_KEYSTORE_CLIENT_IMPL_H_
16 #define KEYSTORE_KEYSTORE_CLIENT_IMPL_H_
17 
18 #include "keystore_client.h"
19 
20 #include <future>
21 #include <map>
22 #include <optional>
23 #include <string>
24 #include <vector>
25 
26 #include <android/security/keystore/IKeystoreService.h>
27 #include <binder/IBinder.h>
28 #include <binder/IServiceManager.h>
29 #include <utils/StrongPointer.h>
30 
31 namespace keystore {
32 
33 class KeystoreClientImpl : public KeystoreClient {
34   public:
35     KeystoreClientImpl();
36     ~KeystoreClientImpl() override = default;
37 
38     // KeystoreClient methods.
39     bool encryptWithAuthentication(const std::string& key_name, const std::string& data,
40                                    int32_t flags, std::string* encrypted_data) override;
41     bool decryptWithAuthentication(const std::string& key_name, const std::string& encrypted_data,
42                                    std::string* data) override;
43     bool oneShotOperation(KeyPurpose purpose, const std::string& key_name,
44                           const keystore::AuthorizationSet& input_parameters,
45                           const std::string& input_data, const std::string& signature_to_verify,
46                           keystore::AuthorizationSet* output_parameters,
47                           std::string* output_data) override;
48     KeyStoreNativeReturnCode addRandomNumberGeneratorEntropy(const std::string& entropy,
49                                                              int32_t flags) override;
50     KeyStoreNativeReturnCode
51     generateKey(const std::string& key_name, const keystore::AuthorizationSet& key_parameters,
52                 int32_t flags, keystore::AuthorizationSet* hardware_enforced_characteristics,
53                 keystore::AuthorizationSet* software_enforced_characteristics) override;
54     KeyStoreNativeReturnCode
55     getKeyCharacteristics(const std::string& key_name,
56                           keystore::AuthorizationSet* hardware_enforced_characteristics,
57                           keystore::AuthorizationSet* software_enforced_characteristics) override;
58     KeyStoreNativeReturnCode
59     importKey(const std::string& key_name, const keystore::AuthorizationSet& key_parameters,
60               KeyFormat key_format, const std::string& key_data,
61               keystore::AuthorizationSet* hardware_enforced_characteristics,
62               keystore::AuthorizationSet* software_enforced_characteristics) override;
63     KeyStoreNativeReturnCode exportKey(KeyFormat export_format, const std::string& key_name,
64                                        std::string* export_data) override;
65     KeyStoreNativeReturnCode deleteKey(const std::string& key_name) override;
66     KeyStoreNativeReturnCode deleteAllKeys() override;
67     KeyStoreNativeReturnCode beginOperation(KeyPurpose purpose, const std::string& key_name,
68                                             const keystore::AuthorizationSet& input_parameters,
69                                             keystore::AuthorizationSet* output_parameters,
70                                             uint64_t* handle) override;
71     KeyStoreNativeReturnCode updateOperation(uint64_t handle,
72                                              const keystore::AuthorizationSet& input_parameters,
73                                              const std::string& input_data,
74                                              size_t* num_input_bytes_consumed,
75                                              keystore::AuthorizationSet* output_parameters,
76                                              std::string* output_data) override;
77     KeyStoreNativeReturnCode finishOperation(uint64_t handle,
78                                              const keystore::AuthorizationSet& input_parameters,
79                                              const std::string& input_data,
80                                              const std::string& signature_to_verify,
81                                              keystore::AuthorizationSet* output_parameters,
82                                              std::string* output_data) override;
83     KeyStoreNativeReturnCode abortOperation(uint64_t handle) override;
84     bool doesKeyExist(const std::string& key_name) override;
85     bool listKeys(const std::string& prefix, std::vector<std::string>* key_name_list) override;
86     bool listKeysOfUid(const std::string& prefix, int uid,
87                        std::vector<std::string>* key_name_list) override;
88     std::optional<std::vector<uint8_t>> getKey(const std::string& alias, int uid) override;
89 
90   private:
91     // Returns an available virtual operation handle.
92     uint64_t getNextVirtualHandle();
93 
94     // Maps a keystore error code to a code where all success cases use
95     // KM_ERROR_OK (not keystore's NO_ERROR).
96     //    int32_t mapKeystoreError(int32_t keystore_error);
97 
98     // Creates an encryption key suitable for EncryptWithAuthentication or
99     // verifies attributes if the key already exists. Returns true on success.
100     bool createOrVerifyEncryptionKey(const std::string& key_name, int32_t flags);
101 
102     // Creates an authentication key suitable for EncryptWithAuthentication or
103     // verifies attributes if the key already exists. Returns true on success.
104     bool createOrVerifyAuthenticationKey(const std::string& key_name, int32_t flags);
105 
106     // Verifies attributes of an encryption key suitable for
107     // EncryptWithAuthentication. Returns true on success and populates |verified|
108     // with the result of the verification.
109     bool verifyEncryptionKeyAttributes(const std::string& key_name, bool* verified);
110 
111     // Verifies attributes of an authentication key suitable for
112     // EncryptWithAuthentication. Returns true on success and populates |verified|
113     // with the result of the verification.
114     bool verifyAuthenticationKeyAttributes(const std::string& key_name, bool* verified);
115 
116     android::sp<android::IServiceManager> service_manager_;
117     android::sp<android::IBinder> keystore_binder_;
118     android::sp<android::security::keystore::IKeystoreService> keystore_;
119     uint64_t next_virtual_handle_ = 1;
120     std::map<uint64_t, android::sp<android::IBinder>> active_operations_;
121 
122     DISALLOW_COPY_AND_ASSIGN(KeystoreClientImpl);
123 };
124 
125 }  // namespace keystore
126 
127 #endif  // KEYSTORE_KEYSTORE_CLIENT_IMPL_H_
128