[gdm-list] how to "talk" with gdm

[Anderson Goulart <global codekab com>]

Hello all,


I am trying to develop a simple window with one entry (pin code) to authenticate an smartcard on GDM 2.24. I am studying gdm code for a few days trying to find a simple way to do that. I could have some ideas, but I got lost on gobject code and IPC mechanism used. Looking at GdmGreeterLoginWindow object I saw that it register some signals and when the password is captured a "query-answer" signal is emited. But I could not understand how this signal get captured by gdm-slave process and how this information is sent (encapsulated). Could anyone explain how it works?

To avoid modifying gdm source code and making things easier, I wrote a simple binary that reads from dbus the information of insertion/removing the smartcard and show/hide the PIN code window entry. Now what I just need is to send this text_entry to gdm daemon (and obviously, PAM - pam_pkcs11). Any ideas on how can I do that? 

ps: this program is started by gdm autostart (/usr/share/gdm/autostart/LoginWindow/program.desktop). It is working on the sense of appearing and disappearing the window, but not the "talk mechanism" with gdm to verify the pin code.


Thanks in advance,
Global