14 11 | 2012

Upcoming signing parties in France

Written by Tanguy

Classified in : Homepage, Debian

A seal

I am organizing two signing parties in France:

  • Saturday, November 17th at 12:15 at the JDLL in Lyon;
  • Sunday, November 25th at 11:45 at the Mini-DebConf in Paris.

Read more Upcoming signing parties in France

12 05 | 2012

Signing-party and crypto conference in Paris

Written by Tanguy

Classified in : Homepage, Debian

Statue of Saint Peter holding the heaven's key

Monday 21st during at 18:45, in Paris, there will be a conference organized by Parinux, where I will explain the principles of cryptography and their application in the SSL and PGP systems. This conference will be followed at 20:30 by a signing-party PGP et CAcert.

For the signing-party, I will ask participants to:

  1. generate a key pair if you do not already have one;
  2. send me you public key and register;
  3. print some copies of your key fingerprint;
  4. print the list of participants I will send you;
  5. come with all that stuff and one or two identity documents.

This is a partial translation of the full article I wrote in French, in case foreigners could attend. Sorry for the very late notice…

20 02 | 2012

Opportunistic SSH agent

Written by Tanguy

Classified in : Homepage, Debian, Command line, Lazyweb

To use an SSH agent, one usually has to:

  1. launch the agent;
  2. add his key to it.

The first step can be automated in the desktop or shell startup script (this is a typical use case for login shell-only startup scripts, by the way), but the second one cannot if your private key is protected by a passphrase.

Read more Opportunistic SSH agent

02 09 | 2011

rxvt-unicode: generate key symbols

Written by Tanguy

Classified in : Homepage, Debian, Command line

rxvt-unicode is a terminal emulator with some interesting features. Here is one of them I find most amazing and elegant: it can generate the symbol characters corresponding to keyboard keys.

It works by pressing and releasing ⎈ + ⇧ (⎈ is the symbol for the Control key, and ⇧ is Shift, of course), then the key which symbol you want to get.

For instance, to get the Caps lock symbol, you type ⎈ + ⇧, ⇬, which gives you the following symbol: ⇬. Here are some other nice examples: ↵ (Return) ⇮ (AltGr aka Level3 Shift) ⌫ (BackSpace) ⎀ (Insert) ⌦ (Delete) ⇱ (Home) ⇲ (End) ⇞ (Prior) ⇟ (Next).

Beware that this will not cancel the effect of {Caps, Num} lock keys: you will get their symbols but also enter the corresponding mode.

27 05 | 2011

PGP signatures with trust and verification level

Written by Tanguy

Classified in : Homepage, Debian, To remember

Identity checks and trust

Saint Peter's key, detail from a stone statue

The OpenPGP web of trust is composed of keys linked to each other by two things:

  • identity checks: signing a key means that you verified the link between a key with user IDs, an official identity document with a photograph, and a person with a face;
  • trust: on your public key ring, you manually decide who you trust to correctly check other people's identity.

With these two pieces of information, GnuPG is able to determine whether or not the key of someone you never met can trusted to belong to its alleged owner.


Signing a key is usually a binary action: either you sign it or you do not sign it. Thus your signature on a key will give other people a rough identity check information and no trust information at all.

In fact, the OpenPGP standard does allow to publish precise identity check and trust information on signatures, but unfortunately this is now enabled with GnuPG by default. These features are called certification level and trust signatures.

Read more PGP signatures with trust and verification level