Scripting with "Expect"

Question

I have just started working with "Expect" with hopes of automating password changes. I wanted to know if anyone has any Expect scripts of their own that they could share that would doing something like the following:
1) ssh to remote server A as user jdoe, change the password for jdoe
2) As jdoe, sudo to userB, change userB's password
I want to run an expect script that will do the above from cron so that the script will go out and change both passwords prior to their expiration. Password aging is as follows on the servers:
MAXWEEKS=8
MINWEEKS=0
PASSLENGTH=8
HISTSIZE=10 (remembers last 10 passwords, so they cannot be reused)
I think the mkpasswd utility that comes with Expect could be used, but I could use a good example if someone has one to share.
Thanks for any help !!

Answer 1

I have an update on this that I would like to post in hopes of helping others that may be using Expect to automate password changes. I need some help with the looping if anyone has any suggestions. Here is what I have comeup with so far:
1) The shell script for calling the Expect Script is posted below. Basically, the script will read the old password and new password from pass.old and pass.new. It gets a list of servers, usernames, and sudo accounts from the file servusers which is in the format of:
servername | username | sudo acct
The script then calls the expect script passing.exp and passes information to it required to login, change the password, sudo to a user, and change it's password too. My problem is, the script is not looping. It will read in the first server | user | sudo account from the file and go out and make the change, but when it exits from the first server, it does not move onto the second server in the file which contains a different username and sudo account.
#!/usr/bin/ksh
MYDIR="/scripts/Expect_Scripts/pass_control"
OLDPASS=$(cat ${MYDIR}/pass.old)
NEWPASS=$(cat ${MYDIR}/pass.new)
set -x
for LINE in $(grep -v "^#" ${MYDIR}/servusers);
do
SERVER="$(echo "${LINE}" | awk -F\| '{print $1}')"
LOGINUSER="$(echo "${LINE}" | awk -F\| '{print $2}')"
SUDOACCT="$(echo "${LINE}" | awk -F\| '{print $3}')"
echo "${SERVER},${LOGINUSER},${SUDOACCT}"
${MYDIR}/passing.exp ${LOGINUSER} ${SUDOACCT} ${SERVER} ${OLDPASS} ${NEWPASS}
done
2) Below is the passing.exp Expect script that the Shell script above is calling:
#!/usr/local/bin/expect -f -d
# Script Usage: ./passing.exp user sudoacct host oldpass newpass
set force_conservative 0 ;# set to 1 to force conservative mode even if
;# script wasn't run conservatively originally
if {$force_conservative} {
set send_slow {1 .1}
proc send {ignore arg} {
sleep .1
exp_send -s -- $arg
set progname [lrange [split "$argv0" "/"] end end]
if {$argc < 5} {
send_error "$progname: usage: $progname user sudoacct host oldpass newpass\n"
exit 2
set user [lindex $argv 0]
set sudoacct [lindex $argv 1]
set host [lindex $argv 2]
set oldpass [lindex $argv 3]
set newpass [lindex $argv 4]
set timeout -1
spawn $env(SHELL)
match_max 100000
send -- "ssh $user@$host\r"
expect -exact "ssh $user@$host\r
$user@$host's password: "
send -- "$oldpass\r"
expect -exact "\r
\$ "
send -- "passwd $user\r"
expect "assword:"
send -- "$oldpass\r"
expect "assword:"
send -- "$newpass\r"
expect "assword:"
send -- "$newpass\r"
expect -exact "\r
passwd: password successfully changed for $user\r
\$ "
#### SUDO SECTION ####
send -- "sudo su - $sudoacct\r"
expect -exact "sudo su - $sudoacct\r
Password:"
send -- "$newpass\r"
expect -exact "\r
\$ "
send -- "passwd $sudoacct\r" # Change the password for the sudo account
expect "assword:"
send -- "$oldpass\r"
expect "assword:"
send -- "$newpass\r"
expect "assword:"
send -- "$newpass\r"
expect -exact "\r
passwd: password successfully changed for $sudoacct\r
\$ "
send -- "exit\r"
# expect -exact "exit\r
# \$ "
send -- "exit\r"
expect -exact "exit\r
Connection to $host closed.\r
\r
\$ "
expect eof
Any help on the looping part would be appreciated.