This is a linux PAM implementation of the BitID protocol. Linux system access is granted using just a bitcoin address.
It currently supports pam.d configuration for console or telnet login.
Github: https://github.com/angrycod/libpam-bitid
Example output:
Code:
$ telnet localhost
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
Ubuntu 13.10
bitcoin address: 1DvRd44mD8EuCcym8zymYzabvmozwZ5r8G
challenge message: dbcbd542b29a3c4298651035ae6eaed3
signature: HE8DDp4eAEy61417XTPAQTOqPBcLP2h0Y0sTB9hfFILCv8ZpLzdH6dh/z6+o7A4VwwjM1Qq2SFVcgyf7U51JhdE=
Last login: Wed May 21 18:42:01 PDT 2014 from localhost on pts/17
Welcome to Ubuntu 13.10 (GNU/Linux 3.11.0-12-generic x86_64)
btctest:~$