New Crypto "HAL" API.

/*

 * 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 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;

    virtual status_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) = 0;

private:

    CryptoPlugin(const CryptoPlugin &);

    CryptoPlugin &operator=(const CryptoPlugin &);

};

}  // namespace android

extern "C" {

    extern android::CryptoFactory *createCryptoFactory();

}

#endif  // CRYPTO_API_H_