Issue: Authentication failure if Entra username and local username differ in upper and lower case

[adombeck]

Is there an existing issue for this?

• I have searched the existing issues and found none that matched mine

Describe the issue

Login fails with "Authentication failure" if e.g. the username in Entra contains uppercase letters but I'm trying to log in with the username in lowercase.

The log shows

Sep 12 12:14:33 ubuntu login[215574]: pam_unix(login:account): could not identify user (from getpwnam([email protected]))
Sep 12 12:14:33 ubuntu login[215574]: Authentication failure

Steps to reproduce

1. Log in with a username which differs in upper- or lowercase from the username in Entra. For example, let's say the username in Entra is [email protected] and you try to log in with:

   sudo login [email protected]
   

2. Complete the device authentication
3. Set a password
4. Observe that login fails with Authentication failure

System information and logs

authd version

authd	0.3.4~ppa3

authd-msentraid broker version

name:      authd-msentraid
summary:   MS EntraID Broker for authd
publisher: --
store-url: https://snapcraft.io/authd-msentraid
license:   GPL-3.0
description: |
  Broker that enables OIDC authentication with MS EntraID group management
  for authd.
services:
  authd-msentraid: simple, enabled, active
refresh-date: today at 12:03 CEST
channels:
  0.x/stable:    0.1           2024-08-23 (33) 17MB -
  0.x/candidate: ^                                  
  0.x/beta:      ^                                  
  0.x/edge:      0.1           2024-09-10 (44) 17MB -
installed:       main~2182c5f4            (x1) 17MB -

gnome-shell version

gnome-shell:
  Installed: 46.3.1-1ubuntu1~24.04.1authd1
  Candidate: 46.3.1-1ubuntu1~24.04.1authd1
  Version table:
 *** 46.3.1-1ubuntu1~24.04.1authd1 500
        500 https://ppa.launchpadcontent.net/ubuntu-enterprise-desktop/authd-edge/ubuntu noble/main amd64 Packages
        100 /var/lib/dpkg/status
     46.3.1-1ubuntu1~24.04.1 500
        500 https://ppa.launchpadcontent.net/ubuntu-enterprise-desktop/authd/ubuntu noble/main amd64 Packages
     46.0-0ubuntu6~24.04.4 500
        500 http://de.archive.ubuntu.com/ubuntu noble-updates/main amd64 Packages
     46.0-0ubuntu6~24.04.3 500
        500 http://security.ubuntu.com/ubuntu noble-security/main amd64 Packages
     46.0-0ubuntu5 500
        500 http://de.archive.ubuntu.com/ubuntu noble/main amd64 Packages

Distribution

Distributor ID:	Ubuntu
Description:	Ubuntu 24.04.1 LTS
Release:	24.04
Codename:	noble

Logs

[666773.117338] ubuntu authd[215459]: DEBUG User "<username in lowercase>" is unknown
[666794.091449] ubuntu authd[215459]: 2024/09/12 12:14:33 WARN rpc error: code = NotFound desc =
[666794.095322] ubuntu authd[215459]: 2024/09/12 12:14:33 WARN rpc error: code = NotFound desc =
[666794.095322] ubuntu authd[215459]: 2024/09/12 12:14:33 WARN rpc error: code = NotFound desc =

authd broker configuration

/etc/authd/brokers.d/authd-msentraid.conf

[authd]
name = Microsoft Entra ID
brand_icon = /snap/authd-msentraid/current/broker_icon.png
dbus_name = com.ubuntu.authd.MSEntraID
dbus_object = /com/ubuntu/authd/MSEntraID

authd-msentraid configuration

[oidc]
issuer = https://login.microsoftonline.com/<UUID redacted>/v2.0
client_id = <UUID redacted> 
#client_id = <UUID redacted>

Double check your logs

• I have redacted any sensitive information from the logs