David's requests for clarifications leads me to ask a historical
question... why were the constants in the hash material chosen to be
the old-style packet headers with length-of-length set inconsistently
with their use here? In the following excerpt, the natural
length-of-length would be 2 (4-byte length to follow) rather than 0
(1-byte length to follow). Was this a mistake, an intentional
deviation to prevent some perceived attack, a strange artifact of the
PGP5 implementation, or something else? (This is just a curiosity,
not a request that it be documented.)
without any header. A V4 certification hashes the constant 0xb4 for
user ID certifications or the constant 0xd1 for User Attribute
certifications (which are old-style packet headers with the
length-of-length set to zero), followed by a four-octet number