1/*
2 * Copyright (C) 2017 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 CLEARKEY_SESSION_LIBRARY_H_
18#define CLEARKEY_SESSION_LIBRARY_H_
19
20#include <media/cas/CasAPI.h>
21#include <media/cas/DescramblerAPI.h>
22#include <openssl/aes.h>
23#include <utils/KeyedVector.h>
24#include <utils/Mutex.h>
25#include <utils/RefBase.h>
26
27namespace android {
28struct ABuffer;
29
30namespace clearkeycas {
31class KeyFetcher;
32
33class ClearKeyCasSession : public RefBase {
34public:
35    ssize_t decrypt(
36            bool secure,
37            DescramblerPlugin::ScramblingControl scramblingControl,
38            size_t numSubSamples,
39            const DescramblerPlugin::SubSample *subSamples,
40            const void *srcPtr,
41            void *dstPtr,
42            AString * /* errorDetailMsg */);
43
44    status_t updateECM(KeyFetcher *keyFetcher, void *ecm, size_t size);
45
46private:
47    enum {
48        kNumKeys = 2,
49    };
50    struct KeyInfo {
51        bool valid;
52        AES_KEY contentKey;
53    };
54    sp<ABuffer> mEcmBuffer;
55    Mutex mKeyLock;
56    CasPlugin* mPlugin;
57    KeyInfo mKeyInfo[kNumKeys];
58
59    friend class ClearKeySessionLibrary;
60
61    explicit ClearKeyCasSession(CasPlugin *plugin);
62    virtual ~ClearKeyCasSession();
63    CasPlugin* getPlugin() const { return mPlugin; }
64    status_t decryptPayload(
65            const AES_KEY& key, size_t length, size_t offset, char* buffer) const;
66
67    DISALLOW_EVIL_CONSTRUCTORS(ClearKeyCasSession);
68};
69
70class ClearKeySessionLibrary {
71public:
72    static ClearKeySessionLibrary* get();
73
74    status_t addSession(CasPlugin *plugin, CasSessionId *sessionId);
75
76    sp<ClearKeyCasSession> findSession(const CasSessionId& sessionId);
77
78    void destroySession(const CasSessionId& sessionId);
79
80    void destroyPlugin(CasPlugin *plugin);
81
82private:
83    static Mutex sSingletonLock;
84    static ClearKeySessionLibrary* sSingleton;
85
86    Mutex mSessionsLock;
87    uint32_t mNextSessionId;
88    KeyedVector<CasSessionId, sp<ClearKeyCasSession>> mIDToSessionMap;
89
90    ClearKeySessionLibrary();
91    DISALLOW_EVIL_CONSTRUCTORS(ClearKeySessionLibrary);
92};
93
94} // namespace clearkeycas
95} // namespace android
96
97#endif // CLEARKEY_SESSION_LIBRARY_H_
98