1 /* 2 * Copyright (C) 2012 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 <utils/Errors.h> 18 19 #ifndef CRYPTO_API_H_ 20 21 #define CRYPTO_API_H_ 22 23 namespace android { 24 25 struct AString; 26 struct CryptoPlugin; 27 28 struct CryptoFactory { CryptoFactoryCryptoFactory29 CryptoFactory() {} ~CryptoFactoryCryptoFactory30 virtual ~CryptoFactory() {} 31 32 virtual bool isCryptoSchemeSupported(const uint8_t uuid[16]) const = 0; 33 34 virtual status_t createPlugin( 35 const uint8_t uuid[16], const void *data, size_t size, 36 CryptoPlugin **plugin) = 0; 37 38 private: 39 CryptoFactory(const CryptoFactory &); 40 CryptoFactory &operator=(const CryptoFactory &); 41 }; 42 43 struct CryptoPlugin { 44 enum Mode { 45 kMode_Unencrypted = 0, 46 kMode_AES_CTR = 1, 47 48 // Neither key nor iv are being used in this mode. 49 // Each subsample is encrypted w/ an iv of all zeroes. 50 kMode_AES_WV = 2, // FIX constant 51 }; 52 53 struct SubSample { 54 uint32_t mNumBytesOfClearData; 55 uint32_t mNumBytesOfEncryptedData; 56 }; 57 CryptoPluginCryptoPlugin58 CryptoPlugin() {} ~CryptoPluginCryptoPlugin59 virtual ~CryptoPlugin() {} 60 61 // If this method returns false, a non-secure decoder will be used to 62 // decode the data after decryption. The decrypt API below will have 63 // to support insecure decryption of the data (secure = false) for 64 // media data of the given mime type. 65 virtual bool requiresSecureDecoderComponent(const char *mime) const = 0; 66 67 // To implement resolution constraints, the crypto plugin needs to know 68 // the resolution of the video being decrypted. The media player should 69 // call this method when the resolution is determined and any time it 70 // is subsequently changed. notifyResolutionCryptoPlugin71 virtual void notifyResolution(uint32_t width, uint32_t height) {} 72 73 // If the error returned falls into the range 74 // ERROR_DRM_VENDOR_MIN..ERROR_DRM_VENDOR_MAX, errorDetailMsg should be 75 // filled in with an appropriate string. 76 // At the java level these special errors will then trigger a 77 // MediaCodec.CryptoException that gives clients access to both 78 // the error code and the errorDetailMsg. 79 // Returns a non-negative result to indicate the number of bytes written 80 // to the dstPtr, or a negative result to indicate an error. 81 virtual ssize_t decrypt( 82 bool secure, 83 const uint8_t key[16], 84 const uint8_t iv[16], 85 Mode mode, 86 const void *srcPtr, 87 const SubSample *subSamples, size_t numSubSamples, 88 void *dstPtr, 89 AString *errorDetailMsg) = 0; 90 91 private: 92 CryptoPlugin(const CryptoPlugin &); 93 CryptoPlugin &operator=(const CryptoPlugin &); 94 }; 95 96 } // namespace android 97 98 extern "C" { 99 extern android::CryptoFactory *createCryptoFactory(); 100 } 101 102 #endif // CRYPTO_API_H_ 103