#230 RAR decryptionError bug

[Nathan]

I came across this issue while dealing with a specific .RAR archive and password combination. I don't know that it would be reproducible without such an edge case. I can provide the needed files, but I rather not attach them to this ticket for privacy concerns.

In RarIn.cpp @ line 404:

if (m_BlockHeader.Type == NHeader::NBlockType::kEndOfArchive)
return S_FALSE;

That statement I believe should be moved down below the if (m_CryptoMode && m_BlockHeader.HeadSize > (1 << 10)) statement like so:

if (m_CryptoMode && m_BlockHeader.HeadSize > (1 << 10))
{
decryptionError = true;
errorMessage = k_DecryptionError;
return S_FALSE;
}
if (m_BlockHeader.Type == NHeader::NBlockType::kEndOfArchive)
return S_FALSE;

In other words, I think what is happening is being compared before we validate the HeadSize. If the HeadSize is greater than 1024 and the type so happens to be NHeader::NBlockType::kEndOfArchive it can be uninterrupted.

Perhaps you have a better way of doing it. I haven't dived into the whole code, but I believe the HeadSize should be evaluated first.

[Igor Pavlov]

I'll fix it in next version.
Thanks!!!