The PacketParser should be able to handle old-style signatures
An old-style signature looks like:
A new style signature looks like:
OPS Literal SIG
The PacketParser currently doesn't handle these signatures correctly. Unfortunately, the PacketParser will never be able to handle them fully, because the Signature packet will be returned before the Literal data packet is parsed, which means that the PacketParser can't set the
computed_hash field in the Signature packet without buffering, which we are not going to do. Nevertheless, the PacketParser could recognize these packets, and push/appropriately initialize a HashedReader and make the results available to the user of the packet parser when the container is popped thereby allowing the user to update the
computed_hash field, if desired.
An alternative/complementary approach would be to allow the PacketParser to rewrite these signatures and magically turn them into OnePassSig/Sig packets. This would require buffering some Signature packets, but these are generally small and limited. It should be possible to control this behavior using via the PacketParserBuilder API.