text: /*
   * Copyright (C) 2012 The Android Open Source Project
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  #include <utils/Errors.h>
  
  #ifndef CRYPTO_API_H_
  
  #define CRYPTO_API_H_
  
  namespace android {
  
  struct AString;
  struct CryptoPlugin;
  
  struct CryptoFactory {
      CryptoFactory() {}
      virtual ~CryptoFactory() {}
  
      virtual bool isCryptoSchemeSupported(const uint8_t uuid[16]) const = 0;
  
      virtual status_t createPlugin(
              const uint8_t uuid[16], const void *data, size_t size,
              CryptoPlugin **plugin) = 0;
  
  private:
      CryptoFactory(const CryptoFactory &);
      CryptoFactory &operator=(const CryptoFactory &);
  };
  
  struct CryptoPlugin {
      enum Mode {
          kMode_Unencrypted = 0,
          kMode_AES_CTR     = 1,
  
          // Neither key nor iv are being used in this mode.
          // Each subsample is encrypted w/ an iv of all zeroes.
          kMode_AES_WV      = 2,  // FIX constant
      };
  
      struct SubSample {
          size_t mNumBytesOfClearData;
          size_t mNumBytesOfEncryptedData;
      };
  
      CryptoPlugin() {}
      virtual ~CryptoPlugin() {}
  
      // If this method returns false, a non-secure decoder will be used to
      // decode the data after decryption. The decrypt API below will have
      // to support insecure decryption of the data (secure = false) for
      // media data of the given mime type.
      virtual bool requiresSecureDecoderComponent(const char *mime) const = 0;
  
      // If the error returned falls into the range
      // ERROR_DRM_VENDOR_MIN..ERROR_DRM_VENDOR_MAX, errorDetailMsg should be
      // filled in with an appropriate string.
      // At the java level these special errors will then trigger a
      // MediaCodec.CryptoException that gives clients access to both
      // the error code and the errorDetailMsg.
      // Returns a non-negative result to indicate the number of bytes written
      // to the dstPtr, or a negative result to indicate an error.
      virtual ssize_t decrypt(
              bool secure,
              const uint8_t key[16],
              const uint8_t iv[16],
              Mode mode,
              const void *srcPtr,
              const SubSample *subSamples, size_t numSubSamples,
              void *dstPtr,
              AString *errorDetailMsg) = 0;
  
  private:
      CryptoPlugin(const CryptoPlugin &);
      CryptoPlugin &operator=(const CryptoPlugin &);
  };
  
  }  // namespace android
  
  extern "C" {
      extern android::CryptoFactory *createCryptoFactory();
  }
  
  #endif  // CRYPTO_API_H_
  