http://xa63tpfoaqt3zru2ehxjjfbpadwj4ha6qsdvtcqtyr3b7hmt4iaq.b32.i2p/spec.html
The authentication signature may be verified against the Author header (either
in the public or encrypted header sets), but not all messages are authenticated. The unencrypted zip archive may contain the following entries: headers.dat [used in: posts, private messages, metadata posts] Optionally contains headers that are not visible to those who cannot decrypt
the message page$n.dat [used in: posts, private messages] Page $n's contents page$n.cfg [used in: posts, private messages]...