PAM ssh_agent sudo auth

pam_ssh_agent_auth

in sudoers:
Defaults  env_keep += "SSH_CLIENT SSH_CONNECTION SSH_TTY SSH_AUTH_SOCK", timestamp_timeout=0

pam configuration:
/etc/pam.d/sudo

pam rules:
auth, account, session, password


auth required pam_unix.so no_warn try_first_pass nullok

auth sufficient pam_ssh_agent_auth.so file=~/.ssh/authorized_keys