pam_ssh_agent_auth is a PAM module which permits PAM authentication via your keyring in a forwarded ssh-agent.

Release 0.10.3 is stable, and has been tested on FreeBSD, Solaris 10, Solaris 11, RHEL5, RHEL6, Debian Wheezy, Ubuntu 12.04 (LTS), Ubuntu 13.10, Ubuntu 14.04 and Mac OS-X 10.10, 10.11, and macos 10.12.

This module can be used to provide authentication for anything run locally that supports PAM. It was written specifically with the intention of permitting authentication for sudo without password entry, and also has been proven useful for use with su as an alternative to wheel.

It serves as middle ground between the two most common, and suboptimal alternatives for large-scale system administration: allowing rootlogin via ssh, or using NOPASSWD in sudoers. This module allows for ssh public-key authentication, and it does this by leveraging an authentication mechanism you are probably already using, ssh-agent.

There are caveats of course, ssh-agent forwarding has it’s own security risks which must be carefully considered for your environment. In cases where there are not untrustworthy intermediate servers, and you wish to retain traceability, accountability, and required authentication for privileged command invocation, the benefits should outweigh the risks. Release 0.10.3 can be downloaded from SourceForge: https://sourceforge.net/project/showfiles.php?group_id=249556 And from github: https://github.com/jbeverly/pam_ssh_agent_auth

If you encounter any issues with usability or security, please github issues https://github.com/jbeverly/pam_ssh_agent_auth/issues to report problems.

Note that if you wish to use this for sudo, you will need a version of sudo that preserves the env_keep environment during authentication; and ideally a version incorporating my minor patch which ensures RUSER is set during PAM authentication.

If building from github, ensure you populate the submodules with 'git submodule init; git submodule update'

Also note that future development of this pam module is moving to a 2.0 repo located here: https://github.com/jbeverly/pam_ssh_agent_auth-2.0, which will remain based on openssh portable upstream, to hopefully avoid the kind of drift this module experienced over the many years.

LEGACY NOTICE: (very old) sudo 1.6.8p12 does not work correctly with this PAM module, because it clears the environment (even env_keep variables) prior to attempting PAM authentication.

sudo 1.7.2p1 or later is preferred, as it correctly sets PAM_RUSER for authentication.