663 lines
25 KiB
C++
663 lines
25 KiB
C++
// Copyright 2017 Google Inc. All rights reserved.
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//
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file or at
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// https://developers.google.com/open-source/licenses/bsd
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#include "packager/media/crypto/encryption_handler.h"
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#include <stddef.h>
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#include <stdint.h>
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#include <algorithm>
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#include <limits>
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#include "packager/media/base/aes_encryptor.h"
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#include "packager/media/base/aes_pattern_cryptor.h"
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#include "packager/media/base/key_source.h"
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#include "packager/media/base/media_sample.h"
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#include "packager/media/base/audio_stream_info.h"
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#include "packager/media/base/video_stream_info.h"
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#include "packager/media/codecs/video_slice_header_parser.h"
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#include "packager/media/codecs/vp8_parser.h"
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#include "packager/media/codecs/vp9_parser.h"
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namespace shaka {
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namespace media {
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namespace {
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const size_t kCencBlockSize = 16u;
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// The encryption handler only supports a single output.
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const size_t kStreamIndex = 0;
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// The default KID for key rotation is all 0s.
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const uint8_t kKeyRotationDefaultKeyId[] = {
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0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
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};
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// Adds one or more subsamples to |*decrypt_config|. This may add more than one
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// if one of the values overflows the integer in the subsample.
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void AddSubsample(uint64_t clear_bytes,
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uint64_t cipher_bytes,
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DecryptConfig* decrypt_config) {
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CHECK_LT(cipher_bytes, std::numeric_limits<uint32_t>::max());
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const uint64_t kUInt16Max = std::numeric_limits<uint16_t>::max();
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while (clear_bytes > kUInt16Max) {
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decrypt_config->AddSubsample(kUInt16Max, 0);
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clear_bytes -= kUInt16Max;
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}
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if (clear_bytes > 0 || cipher_bytes > 0)
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decrypt_config->AddSubsample(clear_bytes, cipher_bytes);
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}
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uint8_t GetNaluLengthSize(const StreamInfo& stream_info) {
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if (stream_info.stream_type() != kStreamVideo)
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return 0;
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const VideoStreamInfo& video_stream_info =
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static_cast<const VideoStreamInfo&>(stream_info);
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return video_stream_info.nalu_length_size();
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}
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std::string GetStreamLabelForEncryption(
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const StreamInfo& stream_info,
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const std::function<std::string(
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const EncryptionParams::EncryptedStreamAttributes& stream_attributes)>&
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stream_label_func) {
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EncryptionParams::EncryptedStreamAttributes stream_attributes;
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if (stream_info.stream_type() == kStreamAudio) {
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stream_attributes.stream_type =
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EncryptionParams::EncryptedStreamAttributes::kAudio;
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} else if (stream_info.stream_type() == kStreamVideo) {
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const VideoStreamInfo& video_stream_info =
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static_cast<const VideoStreamInfo&>(stream_info);
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stream_attributes.stream_type =
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EncryptionParams::EncryptedStreamAttributes::kVideo;
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stream_attributes.oneof.video.width = video_stream_info.width();
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stream_attributes.oneof.video.height = video_stream_info.height();
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}
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return stream_label_func(stream_attributes);
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}
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} // namespace
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EncryptionHandler::EncryptionHandler(const EncryptionParams& encryption_params,
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KeySource* key_source)
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: encryption_params_(encryption_params),
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protection_scheme_(
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static_cast<FourCC>(encryption_params.protection_scheme)),
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key_source_(key_source) {}
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EncryptionHandler::~EncryptionHandler() {}
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Status EncryptionHandler::InitializeInternal() {
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if (!encryption_params_.stream_label_func) {
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return Status(error::INVALID_ARGUMENT, "Stream label function not set.");
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}
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if (num_input_streams() != 1 || next_output_stream_index() != 1) {
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return Status(error::INVALID_ARGUMENT,
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"Expects exactly one input and output.");
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}
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return Status::OK;
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}
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Status EncryptionHandler::Process(std::unique_ptr<StreamData> stream_data) {
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switch (stream_data->stream_data_type) {
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case StreamDataType::kStreamInfo:
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return ProcessStreamInfo(*stream_data->stream_info);
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case StreamDataType::kSegmentInfo: {
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std::shared_ptr<SegmentInfo> segment_info(new SegmentInfo(
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*stream_data->segment_info));
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segment_info->is_encrypted = remaining_clear_lead_ <= 0;
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const bool key_rotation_enabled = crypto_period_duration_ != 0;
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if (key_rotation_enabled)
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segment_info->key_rotation_encryption_config = encryption_config_;
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if (!segment_info->is_subsegment) {
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if (key_rotation_enabled)
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check_new_crypto_period_ = true;
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if (remaining_clear_lead_ > 0)
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remaining_clear_lead_ -= segment_info->duration;
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}
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return DispatchSegmentInfo(kStreamIndex, segment_info);
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}
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case StreamDataType::kMediaSample:
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return ProcessMediaSample(std::move(stream_data->media_sample));
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default:
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VLOG(3) << "Stream data type "
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<< static_cast<int>(stream_data->stream_data_type) << " ignored.";
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return Dispatch(std::move(stream_data));
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}
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}
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Status EncryptionHandler::ProcessStreamInfo(const StreamInfo& clear_info) {
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if (clear_info.is_encrypted()) {
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return Status(error::INVALID_ARGUMENT,
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"Input stream is already encrypted.");
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}
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DCHECK_NE(kStreamUnknown, clear_info.stream_type());
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DCHECK_NE(kStreamText, clear_info.stream_type());
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std::shared_ptr<StreamInfo> stream_info = clear_info.Clone();
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remaining_clear_lead_ =
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encryption_params_.clear_lead_in_seconds * stream_info->time_scale();
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crypto_period_duration_ =
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encryption_params_.crypto_period_duration_in_seconds *
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stream_info->time_scale();
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codec_ = stream_info->codec();
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nalu_length_size_ = GetNaluLengthSize(*stream_info);
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stream_label_ = GetStreamLabelForEncryption(
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*stream_info, encryption_params_.stream_label_func);
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switch (codec_) {
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case kCodecVP9:
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if (encryption_params_.vp9_subsample_encryption)
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vpx_parser_.reset(new VP9Parser);
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break;
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case kCodecH264:
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header_parser_.reset(new H264VideoSliceHeaderParser);
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break;
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case kCodecH265:
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header_parser_.reset(new H265VideoSliceHeaderParser);
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break;
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default:
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// Other codecs should have nalu length size == 0.
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if (nalu_length_size_ > 0) {
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LOG(WARNING) << "Unknown video codec '" << codec_ << "'";
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return Status(error::ENCRYPTION_FAILURE, "Unknown video codec.");
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}
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}
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if (header_parser_) {
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CHECK_NE(nalu_length_size_, 0u) << "AnnexB stream is not supported yet";
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if (!header_parser_->Initialize(stream_info->codec_config())) {
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return Status(error::ENCRYPTION_FAILURE,
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"Fail to read SPS and PPS data.");
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}
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}
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Status status = SetupProtectionPattern(stream_info->stream_type());
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if (!status.ok())
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return status;
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EncryptionKey encryption_key;
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const bool key_rotation_enabled = crypto_period_duration_ != 0;
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if (key_rotation_enabled) {
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check_new_crypto_period_ = true;
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// Setup dummy key id and key to signal encryption for key rotation.
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encryption_key.key_id.assign(
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kKeyRotationDefaultKeyId,
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kKeyRotationDefaultKeyId + sizeof(kKeyRotationDefaultKeyId));
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// The key is not really used to encrypt any data. It is there just for
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// convenience.
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encryption_key.key = encryption_key.key_id;
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} else {
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status = key_source_->GetKey(stream_label_, &encryption_key);
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if (!status.ok())
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return status;
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}
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if (!CreateEncryptor(encryption_key))
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return Status(error::ENCRYPTION_FAILURE, "Failed to create encryptor");
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stream_info->set_is_encrypted(true);
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stream_info->set_has_clear_lead(encryption_params_.clear_lead_in_seconds > 0);
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stream_info->set_encryption_config(*encryption_config_);
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return DispatchStreamInfo(kStreamIndex, stream_info);
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}
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Status EncryptionHandler::ProcessMediaSample(
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std::shared_ptr<const MediaSample> clear_sample) {
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DCHECK(clear_sample);
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// We need to parse the frame (which also updates the vpx parser) even if the
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// frame is not encrypted as the next (encrypted) frame may be dependent on
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// this clear frame.
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std::vector<VPxFrameInfo> vpx_frames;
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if (vpx_parser_ && !vpx_parser_->Parse(clear_sample->data(),
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clear_sample->data_size(),
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&vpx_frames)) {
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return Status(error::ENCRYPTION_FAILURE, "Failed to parse vpx frame.");
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}
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// Need to setup the encryptor for new segments even if this segment does not
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// need to be encrypted, so we can signal encryption metadata earlier to
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// allows clients to prefetch the keys.
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if (check_new_crypto_period_) {
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const int64_t current_crypto_period_index =
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clear_sample->dts() / crypto_period_duration_;
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if (current_crypto_period_index != prev_crypto_period_index_) {
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EncryptionKey encryption_key;
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Status status = key_source_->GetCryptoPeriodKey(
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current_crypto_period_index, stream_label_, &encryption_key);
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if (!status.ok())
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return status;
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if (!CreateEncryptor(encryption_key))
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return Status(error::ENCRYPTION_FAILURE, "Failed to create encryptor");
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prev_crypto_period_index_ = current_crypto_period_index;
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}
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check_new_crypto_period_ = false;
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}
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// Since there is no encryption needed right now, send the clear copy
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// downstream so we can save the costs of copying it.
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if (remaining_clear_lead_ > 0) {
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return DispatchMediaSample(kStreamIndex, std::move(clear_sample));
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}
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std::unique_ptr<DecryptConfig> decrypt_config(new DecryptConfig(
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encryption_config_->key_id,
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encryptor_->iv(),
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std::vector<SubsampleEntry>(),
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protection_scheme_,
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crypt_byte_block_,
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skip_byte_block_));
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// Now that we know that this sample must be encrypted, make a copy of
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// the sample first so that all the encryption operations can be done
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// in-place.
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std::shared_ptr<MediaSample> cipher_sample(clear_sample->Clone());
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// |cipher_sample| above still contains the old clear sample data. We will
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// use |cipher_sample_data| to hold cipher sample data then transfer it to
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// |cipher_sample| after encryption.
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std::shared_ptr<uint8_t> cipher_sample_data(
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new uint8_t[clear_sample->data_size()], std::default_delete<uint8_t[]>());
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if (vpx_parser_) {
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if (!EncryptVpxFrame(vpx_frames, clear_sample->data(),
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clear_sample->data_size(),
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&cipher_sample_data.get()[0], decrypt_config.get())) {
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return Status(error::ENCRYPTION_FAILURE, "Failed to encrypt VPX frame.");
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}
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DCHECK_EQ(decrypt_config->GetTotalSizeOfSubsamples(),
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clear_sample->data_size());
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} else if (header_parser_) {
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if (!EncryptNalFrame(clear_sample->data(), clear_sample->data_size(),
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&cipher_sample_data.get()[0], decrypt_config.get())) {
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return Status(error::ENCRYPTION_FAILURE, "Failed to encrypt NAL frame.");
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}
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DCHECK_EQ(decrypt_config->GetTotalSizeOfSubsamples(),
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clear_sample->data_size());
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} else if (codec_ == kCodecEAC3 &&
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protection_scheme_ == kAppleSampleAesProtectionScheme) {
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if (!SampleAesEncryptEac3Frame(clear_sample->data(),
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clear_sample->data_size(),
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&cipher_sample_data.get()[0])) {
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return Status(error::ENCRYPTION_FAILURE,
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"Failed to encrypt E-AC3 frame.");
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}
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} else {
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memcpy(&cipher_sample_data.get()[0], clear_sample->data(),
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std::min(clear_sample->data_size(), leading_clear_bytes_size_));
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if (clear_sample->data_size() > leading_clear_bytes_size_) {
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// The residual block is left unecrypted (copied without encryption). No
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// need to do special handling here.
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EncryptBytes(clear_sample->data() + leading_clear_bytes_size_,
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clear_sample->data_size() - leading_clear_bytes_size_,
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&cipher_sample_data.get()[leading_clear_bytes_size_]);
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}
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}
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cipher_sample->TransferData(std::move(cipher_sample_data),
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clear_sample->data_size());
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// Finish initializing the sample before sending it downstream. We must
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// wait until now to finish the initialization as we will lose access to
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// |decrypt_config| once we set it.
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cipher_sample->set_is_encrypted(true);
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cipher_sample->set_decrypt_config(std::move(decrypt_config));
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encryptor_->UpdateIv();
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return DispatchMediaSample(kStreamIndex, std::move(cipher_sample));
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}
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Status EncryptionHandler::SetupProtectionPattern(StreamType stream_type) {
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switch (protection_scheme_) {
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case kAppleSampleAesProtectionScheme: {
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const size_t kH264LeadingClearBytesSize = 32u;
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const size_t kSmallNalUnitSize = 32u + 16u;
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const size_t kAudioLeadingClearBytesSize = 16u;
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switch (codec_) {
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case kCodecH264:
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// Apple Sample AES uses 1:9 pattern for video.
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crypt_byte_block_ = 1u;
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skip_byte_block_ = 9u;
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leading_clear_bytes_size_ = kH264LeadingClearBytesSize;
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min_protected_data_size_ = kSmallNalUnitSize + 1u;
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break;
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case kCodecAAC:
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FALLTHROUGH_INTENDED;
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case kCodecAC3:
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case kCodecEAC3:
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// Audio is whole sample encrypted. We could not use a
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// crypto_byte_block_ of 1 here as if there is one crypto block
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// remaining, it need not be encrypted for video but it needs to be
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// encrypted for audio.
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crypt_byte_block_ = 0u;
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skip_byte_block_ = 0u;
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leading_clear_bytes_size_ = kAudioLeadingClearBytesSize;
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min_protected_data_size_ = leading_clear_bytes_size_ + 15u;
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break;
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default:
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return Status(
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error::ENCRYPTION_FAILURE,
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"Only AAC/AC3/EAC3 and H264 are supported in Sample AES.");
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}
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break;
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}
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case FOURCC_cbcs:
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FALLTHROUGH_INTENDED;
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case FOURCC_cens:
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if (stream_type == kStreamVideo) {
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// Use 1:9 pattern for video.
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crypt_byte_block_ = 1u;
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skip_byte_block_ = 9u;
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} else {
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// Tracks other than video are protected using whole-block full-sample
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// encryption, which is essentially a pattern of 1:0. Note that this may
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// not be the same as the non-pattern based encryption counterparts,
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// e.g. in 'cens' for full sample encryption, the whole sample is
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// encrypted up to the last 16-byte boundary, see 23001-7:2016(E) 9.7;
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// while in 'cenc' for full sample encryption, the last partial 16-byte
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// block is also encrypted, see 23001-7:2016(E) 9.4.2. Another
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// difference is the use of constant iv.
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crypt_byte_block_ = 1u;
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skip_byte_block_ = 0u;
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}
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break;
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default:
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// Not using pattern encryption.
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crypt_byte_block_ = 0u;
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skip_byte_block_ = 0u;
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}
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return Status::OK;
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}
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bool EncryptionHandler::CreateEncryptor(const EncryptionKey& encryption_key) {
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std::unique_ptr<AesCryptor> encryptor;
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switch (protection_scheme_) {
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case FOURCC_cenc:
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encryptor.reset(new AesCtrEncryptor);
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break;
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case FOURCC_cbc1:
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encryptor.reset(new AesCbcEncryptor(kNoPadding));
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break;
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case FOURCC_cens:
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encryptor.reset(new AesPatternCryptor(
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crypt_byte_block_, skip_byte_block_,
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AesPatternCryptor::kEncryptIfCryptByteBlockRemaining,
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AesCryptor::kDontUseConstantIv,
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std::unique_ptr<AesCryptor>(new AesCtrEncryptor())));
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break;
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case FOURCC_cbcs:
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encryptor.reset(new AesPatternCryptor(
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crypt_byte_block_, skip_byte_block_,
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AesPatternCryptor::kEncryptIfCryptByteBlockRemaining,
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AesCryptor::kUseConstantIv,
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std::unique_ptr<AesCryptor>(new AesCbcEncryptor(kNoPadding))));
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break;
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case kAppleSampleAesProtectionScheme:
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if (crypt_byte_block_ == 0 && skip_byte_block_ == 0) {
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auto constant_iv_flag = AesCryptor::kUseConstantIv;
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if (codec_ == kCodecEAC3) {
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// MPEG-2 Stream Encryption Format for HTTP Live Streaming 2.3.1.3
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// Enhanced AC-3: Within an Enhanced AC-3 audio frame, the AES-128
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// cipher block chaining (CBC) initialization vector (IV) is not reset
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// at syncframe boundaries. The IV is reset at the beginning of each
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// audio frame.
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// We'll manage the reset of IV outside of AesCryptor.
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constant_iv_flag = AesCryptor::kDontUseConstantIv;
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}
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encryptor.reset(new AesCbcEncryptor(kNoPadding, constant_iv_flag));
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} else {
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encryptor.reset(new AesPatternCryptor(
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crypt_byte_block_, skip_byte_block_,
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AesPatternCryptor::kSkipIfCryptByteBlockRemaining,
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AesCryptor::kUseConstantIv,
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std::unique_ptr<AesCryptor>(new AesCbcEncryptor(kNoPadding))));
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}
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break;
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default:
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LOG(ERROR) << "Unsupported protection scheme.";
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return false;
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}
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std::vector<uint8_t> iv = encryption_key.iv;
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if (iv.empty()) {
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if (!AesCryptor::GenerateRandomIv(protection_scheme_, &iv)) {
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LOG(ERROR) << "Failed to generate random iv.";
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return false;
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}
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}
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const bool initialized =
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encryptor->InitializeWithIv(encryption_key.key, iv);
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encryptor_ = std::move(encryptor);
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encryption_config_.reset(new EncryptionConfig);
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encryption_config_->protection_scheme = protection_scheme_;
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encryption_config_->crypt_byte_block = crypt_byte_block_;
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encryption_config_->skip_byte_block = skip_byte_block_;
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if (encryptor_->use_constant_iv()) {
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encryption_config_->per_sample_iv_size = 0;
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encryption_config_->constant_iv = iv;
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} else {
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encryption_config_->per_sample_iv_size = static_cast<uint8_t>(iv.size());
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}
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encryption_config_->key_id = encryption_key.key_id;
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encryption_config_->key_system_info = encryption_key.key_system_info;
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return initialized;
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}
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bool EncryptionHandler::EncryptVpxFrame(
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const std::vector<VPxFrameInfo>& vpx_frames,
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const uint8_t* source,
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size_t source_size,
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uint8_t* dest,
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DecryptConfig* decrypt_config) {
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const uint8_t* data = source;
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for (const VPxFrameInfo& frame : vpx_frames) {
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uint16_t clear_bytes =
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static_cast<uint16_t>(frame.uncompressed_header_size);
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uint32_t cipher_bytes = static_cast<uint32_t>(
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|
frame.frame_size - frame.uncompressed_header_size);
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|
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// "VP Codec ISO Media File Format Binding" document requires that the
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// encrypted bytes of each frame within the superframe must be block
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// aligned so that the counter state can be computed for each frame
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// within the superframe.
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// ISO/IEC 23001-7:2016 10.2 'cbc1' 10.3 'cens'
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// The BytesOfProtectedData size SHALL be a multiple of 16 bytes to
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// avoid partial blocks in Subsamples.
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// For consistency, apply block alignment to all frames.
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const uint16_t misalign_bytes = cipher_bytes % kCencBlockSize;
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clear_bytes += misalign_bytes;
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cipher_bytes -= misalign_bytes;
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|
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decrypt_config->AddSubsample(clear_bytes, cipher_bytes);
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memcpy(dest, data, clear_bytes);
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if (cipher_bytes > 0)
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EncryptBytes(data + clear_bytes, cipher_bytes, dest + clear_bytes);
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data += frame.frame_size;
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dest += frame.frame_size;
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}
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// Add subsample for the superframe index if exists.
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const bool is_superframe = vpx_frames.size() > 1;
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if (is_superframe) {
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size_t index_size = source + source_size - data;
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DCHECK_LE(index_size, 2 + vpx_frames.size() * 4);
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DCHECK_GE(index_size, 2 + vpx_frames.size() * 1);
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uint16_t clear_bytes = static_cast<uint16_t>(index_size);
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uint32_t cipher_bytes = 0;
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decrypt_config->AddSubsample(clear_bytes, cipher_bytes);
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memcpy(dest, data, clear_bytes);
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|
}
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|
return true;
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|
}
|
|
|
|
bool EncryptionHandler::EncryptNalFrame(const uint8_t* source,
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|
size_t source_size,
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|
uint8_t* dest,
|
|
DecryptConfig* decrypt_config) {
|
|
DCHECK_NE(nalu_length_size_, 0u);
|
|
DCHECK(header_parser_);
|
|
const Nalu::CodecType nalu_type =
|
|
(codec_ == kCodecH265) ? Nalu::kH265 : Nalu::kH264;
|
|
NaluReader reader(nalu_type, nalu_length_size_, source, source_size);
|
|
|
|
// Store the current length of clear data. This is used to squash
|
|
// multiple unencrypted NAL units into fewer subsample entries.
|
|
uint64_t accumulated_clear_bytes = 0;
|
|
|
|
Nalu nalu;
|
|
NaluReader::Result result;
|
|
while ((result = reader.Advance(&nalu)) == NaluReader::kOk) {
|
|
const uint64_t nalu_total_size = nalu.header_size() + nalu.payload_size();
|
|
if (nalu.is_video_slice() && nalu_total_size >= min_protected_data_size_) {
|
|
uint64_t current_clear_bytes = leading_clear_bytes_size_;
|
|
if (current_clear_bytes == 0) {
|
|
// For video-slice NAL units, encrypt the video slice. This skips
|
|
// the frame header.
|
|
const int64_t video_slice_header_size =
|
|
header_parser_->GetHeaderSize(nalu);
|
|
if (video_slice_header_size < 0) {
|
|
LOG(ERROR) << "Failed to read slice header.";
|
|
return false;
|
|
}
|
|
current_clear_bytes = nalu.header_size() + video_slice_header_size;
|
|
}
|
|
uint64_t cipher_bytes = nalu_total_size - current_clear_bytes;
|
|
|
|
// ISO/IEC 23001-7:2016 10.2 'cbc1' 10.3 'cens'
|
|
// The BytesOfProtectedData size SHALL be a multiple of 16 bytes to
|
|
// avoid partial blocks in Subsamples.
|
|
// CMAF requires 'cenc' scheme BytesOfProtectedData SHALL be a multiple
|
|
// of 16 bytes; while 'cbcs' scheme BytesOfProtectedData SHALL start on
|
|
// the first byte of video data following the slice header.
|
|
if (protection_scheme_ == FOURCC_cbc1 ||
|
|
protection_scheme_ == FOURCC_cens ||
|
|
protection_scheme_ == FOURCC_cenc) {
|
|
const uint16_t misalign_bytes = cipher_bytes % kCencBlockSize;
|
|
current_clear_bytes += misalign_bytes;
|
|
cipher_bytes -= misalign_bytes;
|
|
}
|
|
|
|
accumulated_clear_bytes += nalu_length_size_ + current_clear_bytes;
|
|
AddSubsample(accumulated_clear_bytes, cipher_bytes, decrypt_config);
|
|
memcpy(dest, source, accumulated_clear_bytes);
|
|
source += accumulated_clear_bytes;
|
|
dest += accumulated_clear_bytes;
|
|
accumulated_clear_bytes = 0;
|
|
|
|
DCHECK_EQ(nalu.data() + current_clear_bytes, source);
|
|
EncryptBytes(source, cipher_bytes, dest);
|
|
source += cipher_bytes;
|
|
dest += cipher_bytes;
|
|
} else {
|
|
// For non-video-slice or small NAL units, don't encrypt.
|
|
accumulated_clear_bytes += nalu_length_size_ + nalu_total_size;
|
|
}
|
|
}
|
|
if (result != NaluReader::kEOStream) {
|
|
LOG(ERROR) << "Failed to parse NAL units.";
|
|
return false;
|
|
}
|
|
AddSubsample(accumulated_clear_bytes, 0, decrypt_config);
|
|
memcpy(dest, source, accumulated_clear_bytes);
|
|
return true;
|
|
}
|
|
|
|
bool EncryptionHandler::SampleAesEncryptEac3Frame(const uint8_t* source,
|
|
size_t source_size,
|
|
uint8_t* dest) {
|
|
DCHECK(source);
|
|
DCHECK(dest);
|
|
|
|
std::vector<size_t> syncframe_sizes;
|
|
if (!ExtractEac3SyncframeSizes(source, source_size, &syncframe_sizes))
|
|
return false;
|
|
|
|
// MPEG-2 Stream Encryption Format for HTTP Live Streaming 2.3.1.3 Enhanced
|
|
// AC-3: The IV is reset at the beginning of each audio frame.
|
|
encryptor_->SetIv(encryptor_->iv());
|
|
|
|
for (size_t syncframe_size : syncframe_sizes) {
|
|
memcpy(dest, source, std::min(syncframe_size, leading_clear_bytes_size_));
|
|
if (syncframe_size > leading_clear_bytes_size_) {
|
|
// The residual block is left unecrypted (copied without encryption). No
|
|
// need to do special handling here.
|
|
EncryptBytes(source + leading_clear_bytes_size_,
|
|
syncframe_size - leading_clear_bytes_size_,
|
|
dest + leading_clear_bytes_size_);
|
|
}
|
|
source += syncframe_size;
|
|
dest += syncframe_size;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
void EncryptionHandler::EncryptBytes(const uint8_t* source,
|
|
size_t source_size,
|
|
uint8_t* dest) {
|
|
DCHECK(source);
|
|
DCHECK(dest);
|
|
DCHECK(encryptor_);
|
|
CHECK(encryptor_->Crypt(source, source_size, dest));
|
|
}
|
|
|
|
bool EncryptionHandler::ExtractEac3SyncframeSizes(
|
|
const uint8_t* source,
|
|
size_t source_size,
|
|
std::vector<size_t>* syncframe_sizes) {
|
|
DCHECK(source);
|
|
DCHECK(syncframe_sizes);
|
|
|
|
syncframe_sizes->clear();
|
|
BufferReader frame(source, source_size);
|
|
// ASTC Standard A/52:2012 Annex E: Enhanced AC-3.
|
|
while (frame.HasBytes(1)) {
|
|
uint16_t syncword;
|
|
if (!frame.Read2(&syncword)) {
|
|
LOG(ERROR) << "Not enough bytes for syncword.";
|
|
return false;
|
|
}
|
|
if (syncword != 0x0B77) {
|
|
LOG(ERROR) << "Invalid E-AC3 frame. Seeing 0x" << std::hex << syncword
|
|
<< std::dec
|
|
<< ". The sync frame does not start with "
|
|
"the valid syncword 0x0B77.";
|
|
return false;
|
|
}
|
|
uint16_t stream_type_and_syncframe_size;
|
|
if (!frame.Read2(&stream_type_and_syncframe_size)) {
|
|
LOG(ERROR) << "Not enough bytes for syncframe size.";
|
|
return false;
|
|
}
|
|
// frmsiz = least significant 11 bits. syncframe_size is (frmsiz + 1) * 2.
|
|
const size_t syncframe_size =
|
|
((stream_type_and_syncframe_size & 0x7FF) + 1) * 2;
|
|
if (!frame.SkipBytes(syncframe_size - sizeof(syncword) -
|
|
sizeof(stream_type_and_syncframe_size))) {
|
|
LOG(ERROR) << "Not enough bytes for syncframe. Expecting "
|
|
<< syncframe_size << " bytes.";
|
|
return false;
|
|
}
|
|
syncframe_sizes->push_back(syncframe_size);
|
|
}
|
|
return true;
|
|
}
|
|
|
|
void EncryptionHandler::InjectVpxParserForTesting(
|
|
std::unique_ptr<VPxParser> vpx_parser) {
|
|
vpx_parser_ = std::move(vpx_parser);
|
|
}
|
|
|
|
void EncryptionHandler::InjectVideoSliceHeaderParserForTesting(
|
|
std::unique_ptr<VideoSliceHeaderParser> header_parser) {
|
|
header_parser_ = std::move(header_parser);
|
|
}
|
|
|
|
} // namespace media
|
|
} // namespace shaka
|