Gnus crypto interoperability matrix (or whatever)

[Raymond Scholz <ray-2001@zonix.de>]

* Background

  I was a happy user of PGP 2.6.3i for years and moved on to PGP 5.0i
  one year ago.  MailCrypt was my companion, later on the Gnus
  PGP/MIME stuff.

  Yesterday I decided to switch to gnupg (1.0.4 with RSA) for the
  obvious reasons.  Knowing that there was gpg.el in Gnus' contrib
  directory I read the documentation and installed gpg-2comp.  I had

  (mc-setversion "gpg")
  (setq mml2015-use 'mailcrypt)

  in my .gnus.

* Frustration

  It didn't work at all.  Signing failed, decrypting failed etc.
  Listened to loud music, got moral support from Matthias W.

* Next morning

  Decided to do a systematic approach to see what's wrong with my
  setup.  Below you can see my attempt to test all setups for gnupg I
  could imagine.  The test mail contained 8-bit characters.  My
  key pair is 1024bit RSA, generated with PGP 2.6.3i:
  pub  1024R/8F926461 1997-03-31 Raymond Scholz <rscholz@tzi.de>

* Signing / Encrypting
    
  Message-MML menu PGP/MIME with (setq mml2015-use 'gpg)  

    0. Sign          OK
    1. Encrypt       OK
    2. Sign+Encrypt  FAIL [1]  

  Message-MML menu PGP/MIME with (setq mml2015-use 'mailcrypt)  

    3. Sign          FAIL [2]
    4. Encrypt       OK
    5. Sign+Encrypt  OK

  MailCrypt menu

    6. Sign          OK
    7. Encrypt       OK
    8. Sign+Encrypt  OK


* Verifying / Decrypting, referring to the test case numbers above
  
  `W s' with (setq mml2015-use 'gpg)  
  
   0.      OK
   1.      OK
   2.      --
   3.      --  
   4.      OK
   5.      OK
   6.      OK
   7.      OK
   8.      OK

  `W s' with (setq mml2015-use 'mailcrypt)  
  
   0.      FAIL [3]
   1.      FAIL [4]
   2.      --
   3.      --  
   4.      FAIL [5]
   5.      FAIL [5]
   6.      OK
   7.      FAIL [6]
   8.      FAIL [6]


  MailCrypt menu
  
   0.      FAIL [7]
   1.      FAIL [7]
   2.      --
   3.      --  
   4.      FAIL [7]
   5.      FAIL [7]
   6.      FAIL [7]
   7.      OK
   8.      OK

* Conclusion

  Use gpg.el with gnupg.  


____________
[1] Doesn't ask to sign or not when encrypting.  Why?

[2]
Signaling: (error "Cannot not find PGP hash.")
  signal(error ("Cannot not find PGP hash."))
  error("Cannot not find PGP hash.")
  mml2015-mailcrypt-sign((part (sign . "pgpmime") (tag-location . 416) (contents . "\n\x8f6\x8e4\x8fc\n\nGr\x8fc\x8df\ e, Ray\n-- \nRaymond Scholz - rscholz@zonix.de - PGP - http://www.zonix.de/\n")))
  mml2015-sign((part (sign . "pgpmime") (tag-location . 416) (contents . "\n\x8f6\x8e4\x8fc\n\nGr\x8fc\x8df\ e, Ray\n-- \nRaymond Scholz - rscholz@zonix.de - PGP - http://www.zonix.de/\n")))
  mml-pgpmime-sign-buffer((part (sign . "pgpmime") (tag-location . 416) (contents . "\n\x8f6\x8e4\x8fc\n\nGr\x8fc\x8df\ e, Ray\n-- \nRaymond Scholz - rscholz@zonix.de - PGP - http://www.zonix.de/\n")))
  mml-generate-mime-1((part (sign . "pgpmime") (tag-location . 416) (contents . "\n\x8f6\x8e4\x8fc\n\nGr\x8fc\x8df\ e, Ray\n-- \nRaymond Scholz - rscholz@zonix.de - PGP - http://www.zonix.de/\n")))
  mml-generate-mime()
  message-encode-message-body()
  message-send-mail(nil)
  message-send-via-mail(nil)
  message-send(nil)
  message-send-and-exit(nil)
  call-interactively(message-send-and-exit)

[3] Complains about a bad signature?!

[4] \201's in front of 8-bit characters.

[5] quoted-printable in the decrypted part (`W q' helps)

[6] decrypts but leaves some encrypted fuzz below the message

[7] Message: Found no signed message in this buffer.  Plain MailCrypt
    doesn't understand PGP/MIME.

Cheers, Ray
-- 
http://my.gnus.org/ - To frobly boldnicate what no grobi has nuked before.