From 16dfdcff6e4bb025220b88d5fc132ae48e7cb437 Mon Sep 17 00:00:00 2001 From: "John \"Juce\" Bruce" Date: Tue, 10 Jun 2014 21:12:37 -0700 Subject: Implement OpenSSL-Based Decryptor Implements an object that does AES-CTR-128 by invoking OpenSSL. Change-Id: I8457899ec8b69bd8f0d727029985c9580911cf99 --- drm/mediadrm/plugins/clearkey/AesCtrDecryptor.cpp | 67 +++++++++++++++++++++++ drm/mediadrm/plugins/clearkey/AesCtrDecryptor.h | 44 +++++++++++++++ drm/mediadrm/plugins/clearkey/Android.mk | 13 +++++ drm/mediadrm/plugins/clearkey/ClearKeyTypes.h | 3 +- 4 files changed, 126 insertions(+), 1 deletion(-) create mode 100644 drm/mediadrm/plugins/clearkey/AesCtrDecryptor.cpp create mode 100644 drm/mediadrm/plugins/clearkey/AesCtrDecryptor.h (limited to 'drm') diff --git a/drm/mediadrm/plugins/clearkey/AesCtrDecryptor.cpp b/drm/mediadrm/plugins/clearkey/AesCtrDecryptor.cpp new file mode 100644 index 0000000..01f8d65 --- /dev/null +++ b/drm/mediadrm/plugins/clearkey/AesCtrDecryptor.cpp @@ -0,0 +1,67 @@ +/* + * Copyright (C) 2014 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. + */ + +//#define LOG_NDEBUG 0 +#define LOG_TAG "ClearKeyCryptoPlugin" +#include + +#include + +#include "AesCtrDecryptor.h" + +namespace clearkeydrm { + +static const size_t kBlockBitCount = kBlockSize * 8; + +android::status_t AesCtrDecryptor::decrypt(const android::Vector& key, + const Iv iv, const uint8_t* source, + uint8_t* destination, + const SubSample* subSamples, + size_t numSubSamples, + size_t* bytesDecryptedOut) { + uint32_t blockOffset = 0; + uint8_t previousEncryptedCounter[kBlockSize]; + memset(previousEncryptedCounter, 0, kBlockSize); + + size_t offset = 0; + AES_KEY opensslKey; + AES_set_encrypt_key(key.array(), kBlockBitCount, &opensslKey); + Iv opensslIv; + memcpy(opensslIv, iv, sizeof(opensslIv)); + + for (size_t i = 0; i < numSubSamples; ++i) { + const SubSample& subSample = subSamples[i]; + + if (subSample.mNumBytesOfClearData > 0) { + memcpy(destination + offset, source + offset, + subSample.mNumBytesOfClearData); + offset += subSample.mNumBytesOfClearData; + } + + if (subSample.mNumBytesOfEncryptedData > 0) { + AES_ctr128_encrypt(source + offset, destination + offset, + subSample.mNumBytesOfEncryptedData, &opensslKey, + opensslIv, previousEncryptedCounter, + &blockOffset); + offset += subSample.mNumBytesOfEncryptedData; + } + } + + *bytesDecryptedOut = offset; + return android::OK; +} + +} // namespace clearkeydrm diff --git a/drm/mediadrm/plugins/clearkey/AesCtrDecryptor.h b/drm/mediadrm/plugins/clearkey/AesCtrDecryptor.h new file mode 100644 index 0000000..b416266 --- /dev/null +++ b/drm/mediadrm/plugins/clearkey/AesCtrDecryptor.h @@ -0,0 +1,44 @@ +/* + * Copyright (C) 2014 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. + */ + +#ifndef CLEARKEY_AES_CTR_DECRYPTOR_H_ +#define CLEARKEY_AES_CTR_DECRYPTOR_H_ + +#include +#include +#include +#include + +#include "ClearKeyTypes.h" + +namespace clearkeydrm { + +class AesCtrDecryptor { +public: + AesCtrDecryptor() {} + + android::status_t decrypt(const android::Vector& key, const Iv iv, + const uint8_t* source, uint8_t* destination, + const SubSample* subSamples, size_t numSubSamples, + size_t* bytesDecryptedOut); + +private: + DISALLOW_EVIL_CONSTRUCTORS(AesCtrDecryptor); +}; + +} // namespace clearkeydrm + +#endif // CLEARKEY_AES_CTR_DECRYPTOR_H_ diff --git a/drm/mediadrm/plugins/clearkey/Android.mk b/drm/mediadrm/plugins/clearkey/Android.mk index 22613cc..59e992b 100644 --- a/drm/mediadrm/plugins/clearkey/Android.mk +++ b/drm/mediadrm/plugins/clearkey/Android.mk @@ -17,10 +17,14 @@ LOCAL_PATH:= $(call my-dir) include $(CLEAR_VARS) LOCAL_SRC_FILES := \ + AesCtrDecryptor.cpp \ + JsonWebKey.cpp \ Utils.cpp \ LOCAL_C_INCLUDES := \ bionic \ + external/jsmn \ + external/openssl/include \ frameworks/av/drm/mediadrm/plugins/clearkey \ frameworks/av/include \ frameworks/native/include \ @@ -30,10 +34,19 @@ LOCAL_MODULE := libdrmclearkeyplugin LOCAL_MODULE_PATH := $(TARGET_OUT_VENDOR_SHARED_LIBRARIES)/mediadrm LOCAL_SHARED_LIBRARIES := \ + libcrypto \ liblog \ libstagefright_foundation \ libutils \ +LOCAL_STATIC_LIBRARIES := \ + libjsmn \ + LOCAL_MODULE_TAGS := optional include $(BUILD_SHARED_LIBRARY) + +######################################################################### +# Build unit tests + +include $(LOCAL_PATH)/tests/Android.mk diff --git a/drm/mediadrm/plugins/clearkey/ClearKeyTypes.h b/drm/mediadrm/plugins/clearkey/ClearKeyTypes.h index 65b434f..a28959a 100644 --- a/drm/mediadrm/plugins/clearkey/ClearKeyTypes.h +++ b/drm/mediadrm/plugins/clearkey/ClearKeyTypes.h @@ -18,12 +18,13 @@ #define CLEARKEY_TYPES_H_ #include +#include #include #include namespace clearkeydrm { -const uint8_t kBlockSize = 16; +const uint8_t kBlockSize = AES_BLOCK_SIZE; typedef uint8_t KeyId[kBlockSize]; typedef uint8_t Iv[kBlockSize]; -- cgit v1.1