Homebrew formula for google-authenticator

google-authenticator.rb

class GoogleAuthenticator < Formula
  desc "Google Authenticator PAM module"
  homepage "https://github.com/google/google-authenticator"
  head "https://github.com/google/google-authenticator.git"

  depends_on "autoconf" => :build
  depends_on "automake" => :build
  depends_on "libtool" => :build

  def install
    cd "libpam" do
      system "./bootstrap.sh"
      system "./configure", "--prefix=#{prefix}"
      system "make", "install"
    end
  end

  def caveats; <<-EOS.undent
    For SSH two-factor authentication, add the following line to /etc/pam.d/sshd:

        auth required /usr/local/lib/security/pam_google_authenticator.so nullok

    Create a token:

        google-authenticator --time-based --disallow-reuse --minimal-window --rate-limit=3 --rate-time=30 -f
    EOS
  end

  test do
    system "#{bin}/google-authenticator", "-h"
  end
end