Subject: Packets sequences

From: "Hasnain Mujtaba" <[email-masked]>
Date: Tue, 9 Mar 2004 19:58:18 -0500

Hi all, 

RFC 2440 states:

   5.7. Symmetrically Encrypted Data Packet (Tag 9)   
   The Symmetrically Encrypted Data packet contains data encrypted with
   a symmetric-key algorithm. When it has been decrypted, it will
   typically contain other packets (often literal data packets or
   compressed data packets).

Just to be sure that I understand this properly, does this mean that an
encrypted message can contain a variable length sequence of literal data
packets and/or compressed data packets, e.g, is this sequence possible?

Encrypted data packet = {literal data packet1, compressed data packet1,
literal data packet2}, where the compressed data packet1 can itself hold
a sequence of literal data packets. 

Thanks
Hasnain.

---

From: David Shaw <[email-masked]>
Date: Tue, 9 Mar 2004 21:43:59 -0500

> a sequence of literal data packets. 

You know, I don't think it is.  Encrypted(literal1, literal2) is
legal, and Encrypted(compressed(literal1, literal2)) is legal, but
mixing the literals and compressed packets at the same "level" of
encapsulation isn't.  Anyone read the grammar otherwise?

Legal or not, I suspect most parsers would handle it.

David