On Thu, 23 Apr 1998, Jon Callas wrote:
At 02:16 PM 4/23/98 -0400, dontspam-tzeruch(_at_)ceddec(_dot_)com wrote:
5.1 PKESKPs
"An implementation should accept, but not generate a version of 2, which
is equivalent to V3 in all other respects".
Isn't V2 the old format using "1 [16 byte session key] [cksum]" instead
of the PKCS-1 block type 02 for the ESK. PGP 2.3?
As I understand it, the only difference between V2 and V3 was version
number change; it was part of the shift to the RSAREF-based code, and the
version number shift was to force an upgrade to the RSAREF version.
Jon
The internal format of what is RSAen/decrypted changed from 2.2 to 2.3,
but not the version number. I don't know what the RFC says.
So I can get a version with 2 and the old (pre RSAREF) format DEK.
http://www.chem.swin.edu.au/~graeme/pgformat/pgformat_1.html
Note: packets that contain a version byte of 2 will contain a version
byte of 3 when using versions of PGP >= 2.6 after 9/1/94.
Page 7 has the version (==2) byte.
Page 10 describes the DEK...
The DEK has no CTB packet framing. The DEK is stored packetless and naked,
with padding, encrypted inside the MPI in the RSA public-key-encrypted
packet.
[in the following it says "message digest", but means DEK]
PGP versions 2.3 and later use a new format for encoding the message
digest into the MPI in the signature packet. (This format is not presently
based on any RFCs due to the use of the IDEA encryption system.) This
format is accepted but not written by version 2.2. The older format used
by versions 2.2 and earlier is also accepted by versions up to 2.4, but
the RSAREF code in 2.5 is unable to cope with it.
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