ykpamcfg - Manage user settings for the Yubico PAM module

NAME SYNOPSIS OPTIONS ACTIONS add_hmac_chalresp EXAMPLES BUGS SEE ALSO

NAME

ykpamcfg − Manage user settings for the Yubico PAM module

SYNOPSIS

ykpamcfg [−1 | −2] [−A] [−p] [−i] [−v] [−V] [−h]

OPTIONS

−1

Use slot 1. This is the default.

−2

Use slot 2.

−A action

Choose action to perform. See ACTIONS below.

−p path

Specify output file, default is ˜/.yubico/challenge.

−i iterations

Number of iterations to use for PBKDF2 of expected response.

−v

Enable verbose mode.

−V

Display version and exit.

−h

Display help and exit.

The PAM module can utilize the HMAC−SHA1 Challenge−response (C/R) mode found in YubiKeys starting with version 2.2 for offline authentication. This action creates the initial state information with the C/R to be issued at the next logon.

The utility currently outputs the state information to a file in the current user’s home directory (˜/.yubico/challenge−123456 for a YubiKey with serial number API readout enabled, and ˜/.yubico/challenge for one without).

The PAM module supports a system−wide directory for these state files (in case the user’s home directories are encrypted), but in a system−wide directory, the challenge part should be replaced with the username. Example: /var/yubico/challenges/alice−123456

To use the system−wide mode, you currently have to move the generated state files manually and configure the PAM module accordingly.

EXAMPLES

First, program a YubiKey for challenge−response on slot 2:

$ ykpersonalize −2 −ochal−resp −ochal−hmac −ohmac−lt64 −oserial−api−visible
...
Commit? (y/n) [n]: y

Now, set the current user to require this YubiKey for logon:

$ ykpamcfg −2 −v
...
Stored initial challenge and expected response in '/home/alice/.yubico/challenge−123456'.

Then, configure authentication with PAM for example like this (make a backup first):

/etc/pam.d/common−auth (from Ubuntu 10.10):

auth required pam_unix.so nullok_secure try_first_pass
auth [success=1 new_authtok_reqd=ok ignore=ignore default=die] pam_yubico.so mode=challenge−response
auth requisite pam_deny.so
auth required pam_permit.so
auth optional pam_ecryptfs.so unwrap

BUGS

Report ykpamcfg bugs in the issue tracker: https://github.com/Yubico/yubico−pam/issues