#! /usr/bin/env expect

#+
# NAME:
#	hammer_ssh.exp
# PURPOSE:
#	"Expect" wrapper for single command for passphrase request
# CATEGORY:
#	caida/gen/expect
# CALLING SEQUENCE:
#	hammer_ssh.exp pwd_file cmd
# INPUTS:
#	pwd_file	name of file containing passphrase
#	cmd		command that needs access to remote machines over ssh
# PROCEDURE:
#	The passphrase is used to load all needed keys into ssh-agent.
#	The agent process is killed upon completion.
#	The assumption is that public key access is set up with all remote
#	machines.
# MODIFICATION HISTORY:
#	SEP-2009, Paul Hick (UCSD/CAIDA)
#	SEP-2010, Paul Hick (UCSD/CAIDA; pphick@caida.org)
#		First arg is now the name of a file containing the passphrase,
#		instead of the passphrase itself.
#-

# set Variables
set passwd_file [lrange $argv 0 0]
set command [lrange $argv 1 end]

set fp [open "$passwd_file" r]
set passwd [read $fp]
close $fp

set timeout -1
#puts "cmd: $command"
# now connect to remote UNIX box (ipaddr) with given script to execute
spawn bash --login -c "eval `ssh-agent -s`; ssh-add; $command; ssh-agent -k"
match_max 100000
# Look for password prompt
expect "*?assphrase*"
# Send password aka $passwd
send -- "$passwd\r"
# send blank line (\r) to make sure we get back to gui
send -- "\r"
expect eof