Unix-Expect:Capture the output of a command as a expect variable - shell

I am trying to capture the output of a program in unix, and use it as a variable in the expect script. When I excecute the program, I will get something like this:
[user#svr]# ./passwdgenerator
1234*&^^[user#svr]#
As you can see, the "1234*&^^" is the password I want to capture and put it into the expect script:
set user user1
set password [open ./passwdgenerator]
spawn ssh $user#server1.com
expect "password:"
send "$password\r"
Obviously it's not working currently, just wonder how I should write this. Have tried this on the txt file before, worked. but when it is a program output, and for security reason we don't want to store password in the text file, so it doesn't work. Any expert could give me a hand? Greatly greatly appreciated.!

This line
set password [open ./passwdgenerator]
change to
set password [exec ./passwdgenerator]

Related

Sending password with expect in shell script

I have a small problem. I'm trying to scp to a remote server and have the script enter my password for me. In short, I'm trying to automate the password entry process in the prompt. However, every time I run my code I keep receiving the prompt to enter my password. Please help. Thank you.
#!bin/expect
for dest in $(<destinations.txt); do
set pass "password"
scp -r ${dest}:/home/car02fv/QATest.txt /home/car02fv/
expect "car02fv#goxsd1703's password:"
send pass
interact
done

Set OS X password using expect

I'm trying to write a script to update the password of an OS X account to a rotating, centrally-stored value. As a prelude to learning to use tclcurl, I just want to get this prototype script working:
#!/usr/bin/expect
set mgrpassword "newpassword" # this will become a tclcurl command later
spawn passwd manager
expect "New password:"
send "$mgrpassword\n"
expect "Retype new password:"
send "$mgrpassword\n"
puts "\nManager password changed."
exit 0
It runs without errors, but it does nothing; the password for the manager account remains unchanged. I've tried it with both \r and \n but that didn't make any difference. Can anyone see what I'm doing wrong or what steps I'm omitting?
(It will always run with admin rights; that's why there is no 'expect "Old password:"' line.)
Just add one more expect statement at the end, like as follows,
send "$mgrpassword\r"
expect eof
Basically, Expect will work with two feasible commands such as send and expect. If send is used, then it is mandatory to have expect (in most of the cases) afterwards. (while the vice-versa is not required to be mandatory)
This is because without that we will be missing out what is happening in the spawned process as Expect will assume that you simply need to send one string value and not expecting anything else from the session.
Your script can be written in the following way as well which makes it robust with the use of exp_continue. It will make the Expect to run again.
set mgrpassword "newpassword"
spawn passwd manager
expect {
timeout { puts "Timeout happened";exit 0}
"password:" {send "$mgrpassword \r";exp_continue}
eof {puts "Manager password changed"; exit 1}
}
So it turns out that
dscl . passwd /Users/manager [passwordstring]
works a lot better/easier than trying to combine passwd with expect. Hope this helps someone else.

Exporting data from expect script

so i've written a short expect script which logs into a APC Power Distribution Unit interface via telnet and polls the current ampage.
#!/usr/bin/expect
set ip "192.168.0.1"
set username "myusername"
set password "mypassword"
spawn "/bin/bash"
send "telnet $ip\r"
expect "*User Name*"
send "$username\r"
expect "*Password*"
send "$password\r"
expect "*APC*"
send -- "phReading all current\r"
expect "*Success*"
send "quit\r"
expect eof
The script does its job and I see the amps on screen, displayed like this:
apc>phReading all current
E000: Success
1: 7.5 A
apc>quit
What i need to do is 'export' that 7.5 figure, either to a text file or pass it to a bash script as a variable.
Any ideas on how i can do this?
Thank you!
Expect is an extension of TCL, so you have access to all of TCL's constructs.
If I were you I would have the expect script write directly to a file.
See the section "Writing a file" here: http://wiki.tcl.tk/367. It has a simple example for just that. In your case, you will want to open the file for append (a) instead of write (w).
open command documentation at: http://www.tcl.tk/man/tcl8.6/TclCmd/open.htm
Let me know how that works for you.

BASH scripting for username/password constructs

I want to write a simple bash script using ncat to open a connection to a ISP and its port.
The first command would be:
nc address port
Upon doing this, I am prompted first to provide a username. I must hit ENTER, and then I will be prompted to provide a password and then I must hit ENTER again.
After this, I want to open a Terminal process window. Can anyone point me to sufficient resources for this type of scripting?
I know the username and password already, but I'm not too sure how to work around the fact that I must provide it and then hit enter. I'm also unsure how to open a new Terminal proceses.
Thanks in advance!
Check out expect script
Expect
Example:
# Assume $remote_server, $my_user_id, $my_password, and $my_command were read in earlier
# in the script.
# Open a telnet session to a remote server, and wait for a username prompt.
spawn telnet $remote_server
expect "username:"
# Send the username, and then wait for a password prompt.
send "$my_user_id\r"
expect "password:"
# Send the password, and then wait for a shell prompt.
send "$my_password\r"
expect "%"
# Send the prebuilt command, and then wait for another shell prompt.
send "$my_command\r"
expect "%"
# Capture the results of the command into a variable. This can be displayed, or written to disk.
set results $expect_out(buffer)
# Exit the telnet session, and wait for a special end-of-file character.
send "exit\r"
expect eof
The secret lies in the HEREDOC
You can solve this problem with something akin to:
$ command-that-needs-input <<EOF
authenticate here
issue a command
issue another command
EOF
Look at the link I provided for here documents - it includes support for variable substitution and lots of other useful things. Enjoy!

Writing strings to standard input in bash script

I'm trying to automate a startup of a specific service with bash
When the service is started with init.d (/etc/init.d/openvpn.custom) it is promting for username and then password - and then it connects
The auth-user-pass from-file is not possible with the installed version, and it cannot be upgraded because of dependencies
So i'm trying to write a simple bash scripts that executes the init.d script, sleeps for a bit, inputs the username, returns, sleeping a bit, inputting the password - you'll get the flow.
like http://pastebin.com/qWHX7Di5
I've experimented with echo, but it doesent seem to work
This is for a rather legacy firewall i'm asked to keep connected.
Is this even possible?
I would use expect instead of bash. You can still call it from within bash if you need to do other tasks as well.
In expect, the script would be something like the following (untested):
#!/usr/bin/expect -f
set username "username"
set password "password"
spawn /etc/init.d/openvpn.custom start
expect "Username:"
send "$username\r"
expect "Password:"
send "$password\r"
expect eof
You'd want to change the expect "Username:" & expect "Password:" lines to match the actual login prompts that are output by your init.d script.
See the expect man page for further details.
You can try using a here-doc:
/path/to/init.d << END
$username
$password
END

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