I was looking at this image about OAEP:
..and was wondering what was happening here.
We have a data block
DBwhich consists of:
lHash: What is this and where does this come from?
PS: A string of zeros, but how much zeros?
M: clearly our message.
We have a
seedwhich , is some random number. We put this seed into a
MGF, a Mask Generating Function, and XOR the outcome with the
MB. This is our
We put the
MGFagain and XOR it with the
seed. This is our
For the final
EM(encrypted message) we prepend some zeros. What do we do with