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List:       pgp-keyserver-folk
Subject:    Re: The subkey problem
From:       "Stefan Kelm" <kelm () secorvo ! de>
Date:       2001-07-02 8:33:34
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Folks,

we've been discussing this issue quite a while ago. FYI, I'm
forward one of the mails that Hironobi San sent on that topic.
I don't think there have been updates to the pksd recently.

Cheers,

	Stefan.

------- Forwarded message follows -------
From:           	Hironobu SUZUKI <hironobu@h2np.net>
To:             	pgp-keyserver-folk@flame.org
Subject:        	Re: pks not handling multiple subkeys? 
Date sent:      	Sun, 28 Jan 2001 19:30:53 +0900

FYI.

This weekend, I try to read pksd source codes and I realized this
problem is big problem than I thought. This problem was not fixed by
week-end quick hack.

This is a quick memo for my debugging.  (I'm sorry for this memo is
written by strange English :-)

					--hironobu

-----------------------------------------------------------

WHAT'S WRONG
-------------

1) OpenPGP allows multiple public subkeys.

2) In pksd, only-one subkey is allowed and there is no data type for
subkeys list.

See. kd_types.h
---
  typedef struct _sigs_elem {  <== signature packets
   ...
  } sigs_elem;
  typedef struct _userids_elem { <== user id's packets
   ...
  } userids_elem;

  typedef struct _keys_elem {
   xbuffer pubkey;
   xbuffer subkey;  <== ONLY ONE
   xbuffer subkeysig; <== ONLY ONE
  ....
   llist userids;  <== LIST
   llist words;    <== LIST
  } keys_elem;
----

3) When subkey found in new add key, new subkey is appended
keys_elem's subkey element. It causes many problems.

kd_search.c:315
---
	 } else {				/* subkey packet */
=>	    if (!xbuffer_append(&(s->ke->subkey), packet->data, packet->size)) {
	       s->err->fatal = 1;
	       s->err->str = "Appending subkey to key failed";
	       fail();
	    }
---

WHAT'S HAPPENED
---------------

CASE 1:

If new pubkey has multiple subkeys and is added to pksd, all public
subkeys append to only-one xbuffer(s->ke->subkey). This xbuffer (not
list) become meaningless data because subkey area is assumed for
only-one subkey.
 
CASE 2:

If already pubkey exits in pksd, new submitting pubkey's subkeys are
ignored.

CASE 3:

If a pubkey with one-subkey already exits in pksd database and
submitting pubkey's subkeys has any revoke(s) signature, revoke
signature is effective for a pubkey with one-subkey which already
exits in pksd database.

HOW TO FIX IT
-------------

  NOT YET.

------- End of forwarded message -------

-------------------------------------------------------
Dipl.-Inform. Stefan Kelm
Security Consultant

Secorvo Security Consulting GmbH
Albert-Nestler-Strasse 9, D-76131 Karlsruhe

Tel. +49 721 6105-461, Fax +49 721 6105-455
E-Mail kelm@secorvo.de, http://www.secorvo.de
-------------------------------------------------------
PGP Fingerprint 87AE E858 CCBC C3A2 E633 D139 B0D9 212B

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