ssh.exp

#!/usr/bin/env expect

set ERR_UNEXPECTED_OUTPUT 1

set SMALL_TIMEOUT 30
set MEDIUM_TIMEOUT 300
set LONG_TIMEOUT 1800
set LOGIN_RETRY_NUMBER 3

set timeout $SMALL_TIMEOUT

set hostname [lindex $argv 0];
set username [lindex $argv 1];
set password [lindex $argv 2];

# ssh connect
spawn ssh -o UserKnownHostsFile=/dev/null \
          -o StrictHostKeyChecking=no \
          $username@$hostname

expect_after {
    timeout {
        send_user "\n\n*** ERROR: unexpected output\n"
        exit $ERR_UNEXPECTED_OUTPUT
    }
}

set i 1
# login
expect {
    "login:" {
        send "$username\n"
        exp_continue
    }
    
    "password" {
        send "$password\n";
        sleep 1
        incr i
        if { $i > $LOGIN_RETRY_NUMBER } {
            send_user "\n\n*** ERROR: retry login $LOGIN_RETRY_NUMBER fail\n"
            exit $ERR_UNEXPECTED_OUTPUT
        }
        exp_continue
    }

    eof {
        send_user "\n\n*** ERROR: server has closed the connection\n"
        exit $ERR_UNEXPECTED_OUTPUT
    }
}