[net.mail] reading of other people's mail

mark@cbosgd.UUCP (Mark Horton) (06/29/86)

In article <380@nitrex.UUCP> rob@nitrex.UUCP (rob robertson) writes:
>In article <62@houligan.UUCP> dave@smaug.UUCP (Dave Cornutt) writes:
>If your on a unix system sending to a unix system, try mark horton's
>uuencode/uudecode, along with crypt.  Takes a little longer, and is
>a bit of a hastle, but it works.

Thanks for the plug, Rob, although of course uuencode/uudecode are
in the public domain, so it's not like it personally matters to me.

I'd like to mention that RFC 822 has a hook in it specifically for
this.  If you put a header "Encrypted: foo, bar" in there, this
tells the receiving user interface that the mail was encrypted with
method "foo", and it should go invoke the method "foo" decrypter.
"bar" is a hint telling it which key to use for decryption (although
not the key itself, more like an index into a table of keys that has
been agreed upon in advance.)

At the time, I was hoping people would write some enhancements to
popular EMail user interfaces (e.g. Mail/mailx, MH, etc) that would
support this.  So far I haven't seen any.  But given the UNIX crypt,
compress, and uuencode/uudecode, it shouldn't be hard to write one.
(A bit more work and it could be made into a subroutine, possibly
without compressing, so it would be fast.)

If somebody out there would implement this, perhaps we could render
this whole subject moot.

	Mark

ks@svo.UUCP (07/07/86)

Okay, so I am a little slow in reading notes sometimes...

/* Written  8:56 pm  Jun 28, 1986 by mark@cbosgd.UUCP in svo.UUCP:net.mail */
/* ---------- "Re: reading of other people's mail" ---------- */
[...]
I'd like to mention that RFC 822 has a hook in it specifically for
this.  If you put a header "Encrypted: foo, bar" in there, this
tells the receiving user interface that the mail was encrypted with
method "foo" ...

At the time, I was hoping people would write some enhancements to
popular EMail user interfaces (e.g. Mail/mailx, MH, etc) that would
support this.  So far I haven't seen any. ...

If somebody out there would implement this, perhaps we could render
this whole subject moot.

	Mark
/* End of text from svo.UUCP:net.mail */

I'm considering how to write a specification for code which would
transform a plaintext message into a cryptogram and back, and to
provide sufficient 'hooks' to tie it into a mailer (probably MH or
directly to MMDF-II).

I'm semi-convinced to use a vanilla NBS-DES implementation, but I
really have an aversion to block-mode ciphers.  Perhaps someone
can suggest something else (NOT RSA, please).  I'm most interested
in a classic cryptosystem which requires prior exchange of keys.

If anyone is interested in this sufficiently, I can begin to put
together SPECIFICATION suggestions, and a mailing list of interested
individuals.  Writing the code comes after writing the spec.

Cheers.

		Kurt F. Sauer
		Tulsa, Oklahoma
      Internet: ks@a.cs.okstate.EDU
          UUCP: ks@svo.UUCP

"Remember, '01 FE 01 FE 01 FE 01 FE' is a semi-weak DES key."
					-- John B. Boute'