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 #ifndef SYSTEM_KEYMASTER_KEYMASTER1_ENGINE_H_
18 #define SYSTEM_KEYMASTER_KEYMASTER1_ENGINE_H_
19 
20 #include <memory>
21 
22 #include <openssl/ec.h>
23 #include <openssl/engine.h>
24 #include <openssl/ex_data.h>
25 #include <openssl/rsa.h>
26 
27 #include <hardware/keymaster1.h>
28 #include <hardware/keymaster_defs.h>
29 
30 #include <keymaster/android_keymaster_utils.h>
31 #include <keymaster/authorization_set.h>
32 #include <keymaster/km_openssl/openssl_utils.h>
33 
34 
35 namespace keymaster {
36 
37 class Keymaster1Engine {
38   public:
39     /**
40      * Create a Keymaster1Engine, wrapping the provided keymaster1_device.  The engine takes
41      * ownership of the device, and will close it during destruction.
42      */
43     explicit Keymaster1Engine(const keymaster1_device_t* keymaster1_device);
44     ~Keymaster1Engine();
45 
46     keymaster_error_t GenerateKey(const AuthorizationSet& key_description,
47                                   KeymasterKeyBlob* key_material, AuthorizationSet* hw_enforced,
48                                   AuthorizationSet* sw_enforced) const;
49 
50     keymaster_error_t ImportKey(const AuthorizationSet& key_description,
51                                 keymaster_key_format_t input_key_material_format,
52                                 const KeymasterKeyBlob& input_key_material,
53                                 KeymasterKeyBlob* output_key_blob, AuthorizationSet* hw_enforced,
54                                 AuthorizationSet* sw_enforced) const;
55     keymaster_error_t DeleteKey(const KeymasterKeyBlob& blob) const;
56     keymaster_error_t DeleteAllKeys() const;
57 
58     struct KeyData {
KeyDataKeyData59         KeyData(const KeymasterKeyBlob& blob, const AuthorizationSet& params)
60             : op_handle(0), begin_params(params), key_material(blob), error(KM_ERROR_OK),
61               expected_openssl_padding(-1) {}
62 
63         keymaster_operation_handle_t op_handle;
64         AuthorizationSet begin_params;
65         AuthorizationSet finish_params;
66         KeymasterKeyBlob key_material;
67         keymaster_error_t error;
68         int expected_openssl_padding;
69     };
70 
71     RSA* BuildRsaKey(const KeymasterKeyBlob& blob, const AuthorizationSet& additional_params,
72                      keymaster_error_t* error) const;
73     EC_KEY* BuildEcKey(const KeymasterKeyBlob& blob, const AuthorizationSet& additional_params,
74                        keymaster_error_t* error) const;
75 
76     KeyData* GetData(EVP_PKEY* key) const;
77     KeyData* GetData(const RSA* rsa) const;
78     KeyData* GetData(const EC_KEY* rsa) const;
79 
device()80     const keymaster1_device_t* device() const { return keymaster1_device_; }
81 
82     EVP_PKEY* GetKeymaster1PublicKey(const KeymasterKeyBlob& blob,
83                                      const AuthorizationSet& additional_params,
84                                      keymaster_error_t* error) const;
85 
86   private:
87     Keymaster1Engine(const Keymaster1Engine&);  // Uncopyable
88     void operator=(const Keymaster1Engine&);    // Unassignable
89 
90     RSA_METHOD BuildRsaMethod();
91     ECDSA_METHOD BuildEcdsaMethod();
92     void ConfigureEngineForRsa();
93     void ConfigureEngineForEcdsa();
94 
95     keymaster_error_t Keymaster1Finish(const KeyData* key_data, const keymaster_blob_t& input,
96                                        keymaster_blob_t* output);
97 
98     static int duplicate_key_data(CRYPTO_EX_DATA* to, const CRYPTO_EX_DATA* from, void** from_d,
99                                   int index, long argl, void* argp);
100     static void free_key_data(void* parent, void* ptr, CRYPTO_EX_DATA* data, int index, long argl,
101                               void* argp);
102 
103     static int rsa_sign_raw(RSA* rsa, size_t* out_len, uint8_t* out, size_t max_out,
104                             const uint8_t* in, size_t in_len, int padding);
105     static int rsa_decrypt(RSA* rsa, size_t* out_len, uint8_t* out, size_t max_out,
106                            const uint8_t* in, size_t in_len, int padding);
107     static int ecdsa_sign(const uint8_t* digest, size_t digest_len, uint8_t* sig,
108                           unsigned int* sig_len, EC_KEY* ec_key);
109 
110     const keymaster1_device_t* const keymaster1_device_;
111     const std::unique_ptr<ENGINE, ENGINE_Delete> engine_;
112     const int rsa_index_;
113     const int ec_key_index_;
114 
115     const RSA_METHOD rsa_method_;
116     const ECDSA_METHOD ecdsa_method_;
117 
118     static Keymaster1Engine* instance_;
119 };
120 
121 }  // namespace keymaster
122 
123 #endif  // SYSTEM_KEYMASTER_KEYMASTER1_ENGINE_H_
124