Keysigning 2008

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Kultiges Zusammensitzen und gemeinsames Murmeln magischer Zahlen.
-- Gert Döring, FdI 95

What, where & when?

At LinuxTag in Berlin there will be an OpenPGP (pgp/gpg) keysigning party.
The party will be on Friday, May 30th, at 14:00 (sharp), Workshop-Room 1.
The event organizer is Karlheinz Geyer.


Why keysigning?

Please read Chapter 2: "Why should I hold a Keysigning Party?" of the GnuPG Keysigning Party HOWTO.


The party will be conducted using Len Sassaman's Efficient Group Key Signing Method:

  • If you intend to participate please send your key to our keyserver:
 user@computer > gpg --keyserver hkp:// --send-key KEYID
until Sunday, May 25th 2008 21.30 GMT Thank you for your key submissions. No more uploads possible!.
If your entry is not listed at 30 minutes after submission, please send me an email.
  • By Tuesday, May 27th 2008, you can fetch the complete keyring with all the keys submitted and a text file ksp-lt2k8.txt containing the fingerprint of each key on the ring. For downloading the files later, please visit our keyserver at
  • At home, verify that the fingerprint of your key in ksp-lt2k8.txt is correct. Also compute the MD5 and SHA1 hashes of ksp-lt2k8.txt. One way to do this is:
user@computer > md5sum ksp-lt2k8.txt
user@computer > sha1sum ksp-lt2k8.txt
user@computer > gpg --print-md md5 ksp-lt2k8.txt
user@computer > gpg --print-md sha1 ksp-lt2k8.txt
  • Use a pen and write the calculated hashes into the corresponding fields in ksp-lt2k8.txt. You'll find the fields in the top section of the list.
  • Bring a completed hardcopy of ksp-lt2k8.txt with you to LinuxTag.
  • We will recite both the MD5 and SHA1 hashes from ksp-lt2k8.txt. Verify that the recited hash matches what you computed. This guarantees that all participants possess the same list of keys.
  • In turn, each participant will stand and acknowledge that the fingerprint of his/her key listed is correct. Mark the key as verified on your hardcopy. Since we already ensured everyone has the same copy a simple statement like "Yes, this is correct" should be sufficient.
  • The next step is to verify each participant's identity by checking his/her passport or similar identification.
  • When you get home, sign the keys which you were able to check during the party. After you sign a key, send it to its owner together with your signature. You can use caff to automate this if you wish.

Fair play, please! A keysigning party is good for meeting others, sharing interests, and having fun; but the major goal behind the event is to strengthen the "WEB-OF-TRUST" (WoT).
That's why we ask that you finish your signing-work no later than Monday, September 1st 2008.


Prior to the keysigning party, you should have already downloaded the following files from

List of participants
Keyring (compressed using bzip2)
Graphfile (optional)


This is what you have to bring with you:

  • A printout of ksp-lt2k8.txt incl. filled-in MD5 and SHA1 hashes, check that your fingerprint is correct!
  • Some sort of valid(!) government-issued ID-Card (passport or similar).
  • Think about creating a nametag or printing a piece of paper (DIN-A4, landscape) with your listnumber (from ksp-lt2k8.txt) on it. This will save time lining up by allowing you to find your place in line easier.

If you have questions, please do not hesitate to drop me a line: Karlheinz Geyer "streng"

Additional Information


The only keyservers you should use are either or, if you insist. Any of the keyservers in these clusters are fine.

Please do not use other keyservers, like or They all mangle keys in various ways including, but not limited to: dropping subkeys, moving binding sigs around between subkeys, duplicating user ids, modifying signature subpackets (dropping non-hashed data), calculating KeyIDs wrong (for v4 RSA keys), rejecting keys with attribute UIDs (such as photo ids), or they don't sync with the rest of the network.

Therefore please use It's a good idea to upload your key(s) to this keyserver prior to the keysigningparty, use this to do so:

user@computer > gpg --keyserver --send-key KEYID


CA Fire and Forget is a script that helps you with keysigning. It takes a list of keyids on the command line, fetches them from a keyserver and calls GnuPG so that you can sign it. It then mails each key to all its email addresses - only including the one UID that we send to in each mail, pruned from all but self sigs and sigs done by you.

Download: caff (Rev. 365 2008-03-05). Homepage:

If you have Debian you can also install the signing-party package. FreeBSD users can install the signing-party port. For NetBSD users, caff has its own port.
Caff dependencies: gnupg (>= 1.3.92), perl, libgnupg-interface-perl, libmime-perl, libmailtools-perl (>= 1.62)


Uli Martens wrote a small perl script that, given a key ID and ksp-lt2k8.txt, tells you which keys (UIDs) you already signed by annotating the UID with (S).

153  [ ] Fingerprint OK        [ ] ID OK
(S)  pub  1024D/52698E9F 2001-11-07 Uli Martens <>
     Key fingerprint = A48F 8894 37A0 FDE9 60D5  212A 2A58 CEAA 5269 8E9F
(S)  uid     Uli Martens <>
( )  uid     Uli Martens <>
(S)  uid     Uli Martens <>

Download: gpgsigs (Rev. 373 2008-03-16). Homepage:

It requires perl, gnupg (>=1.2.x) and either Locale::Recode (in Debian Package libintl-perl, in testing and unstable) or recode (Debian Package recode).

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