ISOTrackEncryptionBox.cpp [plain text]
#include "config.h"
#include "ISOTrackEncryptionBox.h"
#include <JavaScriptCore/DataView.h>
using JSC::DataView;
namespace WebCore {
bool ISOTrackEncryptionBox::parse(DataView& view, unsigned& offset)
{
if (!ISOFullBox::parse(view, offset))
return false;
offset += 1;
if (!m_version) {
offset += 1;
} else {
int8_t cryptAndSkip = 0;
if (!checkedRead<int8_t>(cryptAndSkip, view, offset, BigEndian))
return false;
m_defaultCryptByteBlock = cryptAndSkip >> 4;
m_defaultSkipByteBlock = cryptAndSkip & 0xF;
}
if (!checkedRead<int8_t>(m_defaultIsProtected, view, offset, BigEndian))
return false;
if (!checkedRead<int8_t>(m_defaultPerSampleIVSize, view, offset, BigEndian))
return false;
auto buffer = view.possiblySharedBuffer();
if (!buffer)
return false;
auto keyIDBuffer = buffer->slice(offset, offset + 16);
offset += 16;
m_defaultKID.resize(16);
memcpy(m_defaultKID.data(), keyIDBuffer->data(), 16);
if (m_defaultIsProtected == 1 && !m_defaultPerSampleIVSize) {
int8_t defaultConstantIVSize = 0;
if (!checkedRead<int8_t>(defaultConstantIVSize, view, offset, BigEndian))
return false;
Vector<uint8_t> defaultConstantIV;
defaultConstantIV.reserveInitialCapacity(defaultConstantIVSize);
while (defaultConstantIVSize--) {
int8_t character = 0;
if (!checkedRead<int8_t>(character, view, offset, BigEndian))
return false;
defaultConstantIV.uncheckedAppend(character);
}
m_defaultConstantIV = WTFMove(defaultConstantIV);
}
return true;
}
}