src/starboard/shared/win32/wrm_header.cc - cobalt - Git at Google

 // Copyright 2017 Google Inc. All Rights Reserved.
 //
 // 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 "starboard/shared/win32/wrm_header.h"

 #include <guiddef.h>
 #include <initguid.h>

 #include <algorithm>

 #include "starboard/byte_swap.h"
 #include "starboard/memory.h"
 #include "starboard/shared/win32/error_utils.h"

 namespace starboard {
 namespace shared {
 namespace win32 {

 using Microsoft::WRL::ComPtr;

 namespace {

 // The playready system id used to create the content header.
 DEFINE_GUID(kPlayreadyContentHeaderCLSID,
             0xF4637010,
             0x03C3,
             0x42CD,
             0xB9,
             0x32,
             0xB4,
             0x8A,
             0xDF,
             0x3A,
             0x6A,
             0x54);

 // The playready system id used to identify the wrm header in the
 // initialization data.
 DEFINE_GUID(kPlayreadyInitializationDataCLSID,
             0x79f0049a,
             0x4098,
             0x8642,
             0xab,
             0x92,
             0xe6,
             0x5b,
             0xe0,
             0x88,
             0x5f,
             0x95);

 const uint16_t kPlayreadyWRMTag = 0x0001;

 class Reader {
  public:
   Reader(const uint8_t* data, size_t length)
       : start_(data), curr_(data), end_(data + length) {}

   size_t GetPosition() const { return curr_ - start_; }
   size_t GetRemaining() const { return end_ - curr_; }

   const uint8_t* curr() const { curr_; }

   bool Skip(size_t distance) {
     if (distance > GetRemaining())
       return false;
     curr_ += distance;
     return true;
   }

   bool ReadGUID(GUID* guid) {
     if (sizeof(*guid) > GetRemaining()) {
       return false;
     }
     SbMemoryCopy(guid, curr_, sizeof(*guid));
     curr_ += sizeof(*guid);
     return true;
   }

   bool ReadBigEndianU32(uint32_t* i) {
     if (sizeof(*i) > GetRemaining())
       return false;
     *i =
         curr_[0] * 0x1000000 + curr_[1] * 0x10000 + curr_[2] * 0x100 + curr_[3];
     curr_ += sizeof(*i);
     return true;
   }

   bool ReadLittleEndianU16(uint16_t* i) {
     if (sizeof(*i) > GetRemaining())
       return false;
     *i = curr_[0] + curr_[1] * 0x100;
     curr_ += sizeof(*i);
     return true;
   }

  private:
   const uint8_t* const start_;
   const uint8_t* curr_;
   const uint8_t* const end_;
 };

 std::vector<uint8_t> ParseWrmHeaderFromInitializationData(
     const void* initialization_data,
     int initialization_data_size) {
   if (initialization_data_size == 0) {
     SB_NOTIMPLEMENTED();
     return std::vector<uint8_t>();
   }

   std::vector<uint8_t> output;
   const uint8_t* data = static_cast<const uint8_t*>(initialization_data);

   Reader reader(data, initialization_data_size);
   while (reader.GetRemaining() > 0) {
     // Parse pssh atom (big endian)
     //
     // 4 bytes -- size
     // 4 bytes -- "pssh"
     // 4 bytes -- flags
     // 16 bytes -- guid
     uint32_t pssh_size;
     if (!reader.ReadBigEndianU32(&pssh_size)) {
       return output;
     }

     // Skipping pssh and flags
     if (!reader.Skip(8)) {
       return output;
     }
     GUID system_id;
     if (!reader.ReadGUID(&system_id)) {
       return output;
     }
     if (system_id != kPlayreadyInitializationDataCLSID) {
       // Skip entire pssh atom
       if (!reader.Skip(pssh_size - 28)) {
         return output;
       }
       continue;
     }

     // 4 bytes -- size of PlayreadyObject
     // followed by PlayreadyObject

     // Skip size, and continue parsing
     if (!reader.Skip(4)) {
       return output;
     }

     // Parse Playready object (little endian)
     // 4 bytes -- size
     // 2 bytes -- record count
     //
     // Playready Record
     // 2 bytes -- type
     // 2 bytes -- size of record
     // n bytes -- record
     if (!reader.Skip(4)) {
       return output;
     }
     uint16_t num_records;
     if (!reader.ReadLittleEndianU16(&num_records)) {
       return output;
     }

     for (int i = 0; i < num_records; i++) {
       uint16_t record_type;
       if (!reader.ReadLittleEndianU16(&record_type)) {
         return output;
       }
       uint16_t record_size;
       if (!reader.ReadLittleEndianU16(&record_size)) {
         return output;
       }
       if ((record_type & kPlayreadyWRMTag) == kPlayreadyWRMTag) {
         std::copy(data + reader.GetPosition(),
                   data + reader.GetPosition() + record_size,
                   std::back_inserter(output));
         return output;
       }
       if (!reader.Skip(record_size)) {
         return output;
       }
     }
   }

   return output;
 }

 uint32_t Base64ToValue(uint8_t byte) {
   if (byte >= 'A' && byte <= 'Z') {
     return byte - 'A';
   }
   if (byte >= 'a' && byte <= 'z') {
     return byte - 'a' + 26;
   }
   if (byte >= '0' && byte <= '9') {
     return byte - '0' + 52;
   }
   if (byte == '+') {
     return 62;
   }
   if (byte == '/') {
     return 63;
   }
   SB_DCHECK(byte == '=');
   return 0;
 }

 std::string Base64Decode(const std::wstring& input) {
   SB_DCHECK(input.size() % 4 == 0);

   std::string output;

   output.reserve(input.size() / 4 * 3);
   for (size_t i = 0; i < input.size() - 3; i += 4) {
     uint32_t decoded =
         Base64ToValue(input[i]) * 4 + Base64ToValue(input[i + 1]) / 16;
     output += static_cast<char>(decoded);
     if (input[i + 2] != '=') {
       decoded = Base64ToValue(input[i + 1]) % 16 * 16 +
                 Base64ToValue(input[i + 2]) / 4;
       output += static_cast<char>(decoded);
       if (input[i + 3] != '=') {
         decoded =
             Base64ToValue(input[i + 2]) % 4 * 64 + Base64ToValue(input[i + 3]);
         output += static_cast<char>(decoded);
       }
     }
   }

   return output;
 }

 GUID ParseKeyIdFromWrmHeader(const std::vector<uint8_t>& wrm_header) {
   // The wrm_header is an XML in wchar_t that contains the base64 encoded key
   // id in <KID> node in base64.  The original key id should be 16 characters,
   // so it is 24 characters after based64 encoded.
   const size_t kEncodedKeyIdLength = 24;

   SB_DCHECK(wrm_header.size() % 2 == 0);
   std::wstring wrm_header_copy(
       reinterpret_cast<const wchar_t*>(wrm_header.data()),
       wrm_header.size() / 2);
   std::wstring::size_type begin = wrm_header_copy.find(L"<KID>");
   if (begin == wrm_header_copy.npos) {
     return WrmHeader::kInvalidKeyId;
   }
   std::wstring::size_type end = wrm_header_copy.find(L"</KID>", begin);
   if (end == wrm_header_copy.npos) {
     return WrmHeader::kInvalidKeyId;
   }
   begin += 5;
   if (end - begin != kEncodedKeyIdLength) {
     return WrmHeader::kInvalidKeyId;
   }

   std::string key_id_in_string =
       Base64Decode(wrm_header_copy.substr(begin, kEncodedKeyIdLength));
   if (key_id_in_string.size() != sizeof(GUID)) {
     return WrmHeader::kInvalidKeyId;
   }

   GUID key_id = *reinterpret_cast<const GUID*>(key_id_in_string.data());

   key_id.Data1 = SbByteSwap(key_id.Data1);
   key_id.Data2 = SbByteSwap(key_id.Data2);
   key_id.Data3 = SbByteSwap(key_id.Data3);

   return key_id;
 }

 ComPtr<IStream> CreateWrmHeaderStream(const std::vector<uint8_t>& wrm_header) {
   ComPtr<IStream> stream;
   HRESULT hr = CreateStreamOnHGlobal(NULL, TRUE, &stream);
   if (FAILED(hr)) {
     return NULL;
   }

   DWORD wrm_header_size = static_cast<DWORD>(wrm_header.size());
   ULONG bytes_written = 0;

   if (wrm_header_size != 0) {
     hr = stream->Write(wrm_header.data(), wrm_header_size, &bytes_written);
     if (FAILED(hr)) {
       return NULL;
     }
   }

   return stream;
 }

 ComPtr<IStream> CreateContentHeaderFromWrmHeader(
     const std::vector<uint8_t>& wrm_header) {
   ComPtr<IStream> content_header;
   // Assume we use one license for one stream.
   const DWORD kNumStreams = 1;
   const DWORD kNextStreamId = static_cast<DWORD>(-1);

   HRESULT hr = CreateStreamOnHGlobal(NULL, TRUE, &content_header);
   if (FAILED(hr)) {
     return NULL;
   }

   // Initialize spInitStm with the required data
   // Format: (All DWORD values are serialized in little-endian order)
   // [GUID (content protection system guid, see msprita.idl)]
   // [DWORD (stream count, use the actual stream count even if all streams are
   // encrypted using the same data, note that zero is invalid)] [DWORD (next
   // stream ID, use -1 if all remaining streams are encrypted using the same
   // data)] [DWORD (next stream's binary data size)] [BYTE* (next stream's
   // binary data)] { Repeat from "next stream ID" above for each stream }
   DWORD wrm_header_size = static_cast<DWORD>(wrm_header.size());
   ULONG bytes_written = 0;
   hr = content_header->Write(&kPlayreadyContentHeaderCLSID,
                              sizeof(kPlayreadyContentHeaderCLSID),
                              &bytes_written);
   if (FAILED(hr)) {
     return NULL;
   }

   hr = content_header->Write(&kNumStreams, sizeof(kNumStreams), &bytes_written);
   if (FAILED(hr)) {
     return NULL;
   }

   hr = content_header->Write(&kNextStreamId, sizeof(kNextStreamId),
                              &bytes_written);
   if (FAILED(hr)) {
     return NULL;
   }

   hr = content_header->Write(&wrm_header_size, sizeof(wrm_header_size),
                              &bytes_written);
   if (FAILED(hr)) {
     return NULL;
   }

   if (0 != wrm_header_size) {
     hr = content_header->Write(wrm_header.data(), wrm_header_size,
                                &bytes_written);
     if (FAILED(hr)) {
       return NULL;
     }
   }

   return content_header;
 }

 ComPtr<IStream> ResetStreamPosition(const ComPtr<IStream>& stream) {
   if (stream == NULL) {
     return NULL;
   }
   LARGE_INTEGER seek_position = {0};
   HRESULT hr = stream->Seek(seek_position, STREAM_SEEK_SET, NULL);
   CheckResult(hr);
   return stream;
 }

 }  // namespace.

 // static
 GUID WrmHeader::kInvalidKeyId;

 WrmHeader::WrmHeader(const void* initialization_data,
                      int initialization_data_size) {
   wrm_header_ = ParseWrmHeaderFromInitializationData(initialization_data,
                                                      initialization_data_size);
   key_id_ = ParseKeyIdFromWrmHeader(wrm_header_);
 }

 ComPtr<IStream> WrmHeader::content_header() const {
   SB_DCHECK(is_valid());

   if (key_id_ == kInvalidKeyId) {
     return NULL;
   }
   return ResetStreamPosition(CreateContentHeaderFromWrmHeader(wrm_header_));
 }

 }  // namespace win32
 }  // namespace shared
 }  // namespace starboard
	// Copyright 2017 Google Inc. All Rights Reserved.
	//
	// 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 "starboard/shared/win32/wrm_header.h"

	#include <guiddef.h>
	#include <initguid.h>

	#include <algorithm>

	#include "starboard/byte_swap.h"
	#include "starboard/memory.h"
	#include "starboard/shared/win32/error_utils.h"

	namespace starboard {
	namespace shared {
	namespace win32 {

	using Microsoft::WRL::ComPtr;

	namespace {

	// The playready system id used to create the content header.
	DEFINE_GUID(kPlayreadyContentHeaderCLSID,
	0xF4637010,
	0x03C3,
	0x42CD,
	0xB9,
	0x32,
	0xB4,
	0x8A,
	0xDF,
	0x3A,
	0x6A,
	0x54);

	// The playready system id used to identify the wrm header in the
	// initialization data.
	DEFINE_GUID(kPlayreadyInitializationDataCLSID,
	0x79f0049a,
	0x4098,
	0x8642,
	0xab,
	0x92,
	0xe6,
	0x5b,
	0xe0,
	0x88,
	0x5f,
	0x95);

	const uint16_t kPlayreadyWRMTag = 0x0001;

	class Reader {
	public:
	Reader(const uint8_t* data, size_t length)
	: start_(data), curr_(data), end_(data + length) {}

	size_t GetPosition() const { return curr_ - start_; }
	size_t GetRemaining() const { return end_ - curr_; }

	const uint8_t* curr() const { curr_; }

	bool Skip(size_t distance) {
	if (distance > GetRemaining())
	return false;
	curr_ += distance;
	return true;
	}

	bool ReadGUID(GUID* guid) {
	if (sizeof(*guid) > GetRemaining()) {
	return false;
	}
	SbMemoryCopy(guid, curr_, sizeof(*guid));
	curr_ += sizeof(*guid);
	return true;
	}

	bool ReadBigEndianU32(uint32_t* i) {
	if (sizeof(*i) > GetRemaining())
	return false;
	*i =
	curr_[0] * 0x1000000 + curr_[1] * 0x10000 + curr_[2] * 0x100 + curr_[3];
	curr_ += sizeof(*i);
	return true;
	}

	bool ReadLittleEndianU16(uint16_t* i) {
	if (sizeof(*i) > GetRemaining())
	return false;
	i = curr_[0] + curr_[1] 0x100;
	curr_ += sizeof(*i);
	return true;
	}

	private:
	const uint8_t* const start_;
	const uint8_t* curr_;
	const uint8_t* const end_;
	};

	std::vector<uint8_t> ParseWrmHeaderFromInitializationData(
	const void* initialization_data,
	int initialization_data_size) {
	if (initialization_data_size == 0) {
	SB_NOTIMPLEMENTED();
	return std::vector<uint8_t>();
	}

	std::vector<uint8_t> output;
	const uint8_t* data = static_cast<const uint8_t*>(initialization_data);

	Reader reader(data, initialization_data_size);
	while (reader.GetRemaining() > 0) {
	// Parse pssh atom (big endian)
	//
	// 4 bytes -- size
	// 4 bytes -- "pssh"
	// 4 bytes -- flags
	// 16 bytes -- guid
	uint32_t pssh_size;
	if (!reader.ReadBigEndianU32(&pssh_size)) {
	return output;
	}

	// Skipping pssh and flags
	if (!reader.Skip(8)) {
	return output;
	}
	GUID system_id;
	if (!reader.ReadGUID(&system_id)) {
	return output;
	}
	if (system_id != kPlayreadyInitializationDataCLSID) {
	// Skip entire pssh atom
	if (!reader.Skip(pssh_size - 28)) {
	return output;
	}
	continue;
	}

	// 4 bytes -- size of PlayreadyObject
	// followed by PlayreadyObject

	// Skip size, and continue parsing
	if (!reader.Skip(4)) {
	return output;
	}

	// Parse Playready object (little endian)
	// 4 bytes -- size
	// 2 bytes -- record count
	//
	// Playready Record
	// 2 bytes -- type
	// 2 bytes -- size of record
	// n bytes -- record
	if (!reader.Skip(4)) {
	return output;
	}
	uint16_t num_records;
	if (!reader.ReadLittleEndianU16(&num_records)) {
	return output;
	}

	for (int i = 0; i < num_records; i++) {
	uint16_t record_type;
	if (!reader.ReadLittleEndianU16(&record_type)) {
	return output;
	}
	uint16_t record_size;
	if (!reader.ReadLittleEndianU16(&record_size)) {
	return output;
	}
	if ((record_type & kPlayreadyWRMTag) == kPlayreadyWRMTag) {
	std::copy(data + reader.GetPosition(),
	data + reader.GetPosition() + record_size,
	std::back_inserter(output));
	return output;
	}
	if (!reader.Skip(record_size)) {
	return output;
	}
	}
	}

	return output;
	}

	uint32_t Base64ToValue(uint8_t byte) {
	if (byte >= 'A' && byte <= 'Z') {
	return byte - 'A';
	}
	if (byte >= 'a' && byte <= 'z') {
	return byte - 'a' + 26;
	}
	if (byte >= '0' && byte <= '9') {
	return byte - '0' + 52;
	}
	if (byte == '+') {
	return 62;
	}
	if (byte == '/') {
	return 63;
	}
	SB_DCHECK(byte == '=');
	return 0;
	}

	std::string Base64Decode(const std::wstring& input) {
	SB_DCHECK(input.size() % 4 == 0);

	std::string output;

	output.reserve(input.size() / 4 * 3);
	for (size_t i = 0; i < input.size() - 3; i += 4) {
	uint32_t decoded =
	Base64ToValue(input[i]) * 4 + Base64ToValue(input[i + 1]) / 16;
	output += static_cast<char>(decoded);
	if (input[i + 2] != '=') {
	decoded = Base64ToValue(input[i + 1]) % 16 * 16 +
	Base64ToValue(input[i + 2]) / 4;
	output += static_cast<char>(decoded);
	if (input[i + 3] != '=') {
	decoded =
	Base64ToValue(input[i + 2]) % 4 * 64 + Base64ToValue(input[i + 3]);
	output += static_cast<char>(decoded);
	}
	}
	}

	return output;
	}

	GUID ParseKeyIdFromWrmHeader(const std::vector<uint8_t>& wrm_header) {
	// The wrm_header is an XML in wchar_t that contains the base64 encoded key
	// id in <KID> node in base64. The original key id should be 16 characters,
	// so it is 24 characters after based64 encoded.
	const size_t kEncodedKeyIdLength = 24;

	SB_DCHECK(wrm_header.size() % 2 == 0);
	std::wstring wrm_header_copy(
	reinterpret_cast<const wchar_t*>(wrm_header.data()),
	wrm_header.size() / 2);
	std::wstring::size_type begin = wrm_header_copy.find(L"<KID>");
	if (begin == wrm_header_copy.npos) {
	return WrmHeader::kInvalidKeyId;
	}
	std::wstring::size_type end = wrm_header_copy.find(L"</KID>", begin);
	if (end == wrm_header_copy.npos) {
	return WrmHeader::kInvalidKeyId;
	}
	begin += 5;
	if (end - begin != kEncodedKeyIdLength) {
	return WrmHeader::kInvalidKeyId;
	}

	std::string key_id_in_string =
	Base64Decode(wrm_header_copy.substr(begin, kEncodedKeyIdLength));
	if (key_id_in_string.size() != sizeof(GUID)) {
	return WrmHeader::kInvalidKeyId;
	}

	GUID key_id = reinterpret_cast<const GUID>(key_id_in_string.data());

	key_id.Data1 = SbByteSwap(key_id.Data1);
	key_id.Data2 = SbByteSwap(key_id.Data2);
	key_id.Data3 = SbByteSwap(key_id.Data3);

	return key_id;
	}

	ComPtr<IStream> CreateWrmHeaderStream(const std::vector<uint8_t>& wrm_header) {
	ComPtr<IStream> stream;
	HRESULT hr = CreateStreamOnHGlobal(NULL, TRUE, &stream);
	if (FAILED(hr)) {
	return NULL;
	}

	DWORD wrm_header_size = static_cast<DWORD>(wrm_header.size());
	ULONG bytes_written = 0;

	if (wrm_header_size != 0) {
	hr = stream->Write(wrm_header.data(), wrm_header_size, &bytes_written);
	if (FAILED(hr)) {
	return NULL;
	}
	}

	return stream;
	}

	ComPtr<IStream> CreateContentHeaderFromWrmHeader(
	const std::vector<uint8_t>& wrm_header) {
	ComPtr<IStream> content_header;
	// Assume we use one license for one stream.
	const DWORD kNumStreams = 1;
	const DWORD kNextStreamId = static_cast<DWORD>(-1);

	HRESULT hr = CreateStreamOnHGlobal(NULL, TRUE, &content_header);
	if (FAILED(hr)) {
	return NULL;
	}

	// Initialize spInitStm with the required data
	// Format: (All DWORD values are serialized in little-endian order)
	// [GUID (content protection system guid, see msprita.idl)]
	// [DWORD (stream count, use the actual stream count even if all streams are
	// encrypted using the same data, note that zero is invalid)] [DWORD (next
	// stream ID, use -1 if all remaining streams are encrypted using the same
	// data)] [DWORD (next stream's binary data size)] [BYTE* (next stream's
	// binary data)] { Repeat from "next stream ID" above for each stream }
	DWORD wrm_header_size = static_cast<DWORD>(wrm_header.size());
	ULONG bytes_written = 0;
	hr = content_header->Write(&kPlayreadyContentHeaderCLSID,
	sizeof(kPlayreadyContentHeaderCLSID),
	&bytes_written);
	if (FAILED(hr)) {
	return NULL;
	}

	hr = content_header->Write(&kNumStreams, sizeof(kNumStreams), &bytes_written);
	if (FAILED(hr)) {
	return NULL;
	}

	hr = content_header->Write(&kNextStreamId, sizeof(kNextStreamId),
	&bytes_written);
	if (FAILED(hr)) {
	return NULL;
	}

	hr = content_header->Write(&wrm_header_size, sizeof(wrm_header_size),
	&bytes_written);
	if (FAILED(hr)) {
	return NULL;
	}

	if (0 != wrm_header_size) {
	hr = content_header->Write(wrm_header.data(), wrm_header_size,
	&bytes_written);
	if (FAILED(hr)) {
	return NULL;
	}
	}

	return content_header;
	}

	ComPtr<IStream> ResetStreamPosition(const ComPtr<IStream>& stream) {
	if (stream == NULL) {
	return NULL;
	}
	LARGE_INTEGER seek_position = {0};
	HRESULT hr = stream->Seek(seek_position, STREAM_SEEK_SET, NULL);
	CheckResult(hr);
	return stream;
	}

	} // namespace.

	// static
	GUID WrmHeader::kInvalidKeyId;

	WrmHeader::WrmHeader(const void* initialization_data,
	int initialization_data_size) {
	wrm_header_ = ParseWrmHeaderFromInitializationData(initialization_data,
	initialization_data_size);
	key_id_ = ParseKeyIdFromWrmHeader(wrm_header_);
	}

	ComPtr<IStream> WrmHeader::content_header() const {
	SB_DCHECK(is_valid());

	if (key_id_ == kInvalidKeyId) {
	return NULL;
	}
	return ResetStreamPosition(CreateContentHeaderFromWrmHeader(wrm_header_));
	}

	} // namespace win32
	} // namespace shared
	} // namespace starboard