I need to be able to return a different password after the first one fails which will be the second time the prompt asks for the same expect value "Password:"
(expect -c "
#exp_internal 1
set passwords {PASS1 PASS2}
set index 0
set timeout 20
# Start the session with the input variable and the rest of the hostname
spawn telnet $host
set timeout 3
expect {
-ex \"Password:\" {
send \"[lindex $passwords $index]\r\"
incr index
exp_continue;
}
}
I just can't get it to work. It looks like there is nothing in the lindex send:
-ex "Password:" {
send "[lindex ]\r"
The problem is you're using double quotes to group the expect script -- bash is interpreting the $variables as bash variables. You need to either:
use single quotes to delimit the script, or
escape all the \$expect_variables so bash does not substitute them first.
Related
I'm trying to write a shell function that spawns a ssh process and authentificates with a password. Then, I'd like to use the spawned process to do further stuff with expect.
Here's the function I have so far:
ssh_cmd() {
ssh $USER#$HOST 2>&1 | expect -c "
log_user 0
set timeout 5
expect password: {
send \"$PASS\n\"
sleep 2
log_user 1
}
"
}
And then I'd like to use given function in other places to interact with the ssh process like this:
ssh_cmd | expect -c "
expect '#' {
send pwd\n
send exit\n
}
expect eof
"
However, running the ssh_cmd function with -d option for expect I get the following result:
expect version 5.45.4
expect: does "" (spawn_id exp0) match glob pattern "password:"? no
ubnt#ui1's password: expect: timed out
From what I understand, the output of ssh does not get piped correctly. I know the common way to do this would be to use spawn, but that would mean the process would get killed after expect exits and I could not have a generic function that authentificates ssh sessions and keeps the process alive for further usage.
What you're designing won't work. Expect needs the process to be spawned from within the expect interpreter using the spawn command. Passing the command's stdout into expect is insufficient.
You could try this:
ssh_cmd() {
# a default bit of code if user does not provide one.
# you probably want some checking and emit an error message.
local user_code=${1:-set timeout 1; send "exit\r"; expect eof}
expect -c "
log_user 0
set timeout 5
spawn ssh -l $USER $HOST
expect password: {
send \"$PASS\n\"
sleep 2
log_user 1
}
$user_code
"
}
and then invoke it like:
ssh_cmd '
expect "#" {
send pwd\r
send exit\r
}
expect eof
'
Note that single quotes have no special meaning in expect, they are just plain characters: you probably don't want to expect the prompt to be the 3 character pattern '#'
I'm including simple Expect commands within a Bash script (I know I could be just writing a pure Expect script, but I would like to get it to work from within Bash).
The script is below:
#!/bin/bash
OUTPUT=$(expect -c '
spawn ssh mihail911#blah.org
expect "password:"
send "dog\r"
')
Upon ssh'ing to the above address, it will return something of the form mihail911's password: on the prompt, so I think my expect line is valid.
When I run this my script does not print anything. It does not even show the password: prompt. In general, even if I manually provide an incorrect password, I will receive a Incorrect password-type response prompt. Why is nothing printing and how can I get my script to execute properly?
I have tried debugging by using the -d flag and it seems to show that at least the first expect prompt is being matched properly.
In addition, what values should I expect in the OUTPUT variable? When I echo this variable, it simply prints the first the first command of the expect portion of the script and then mihail911's password:. Is this what it's supposed to be printing?
Use:
#!/bin/bash
OUTPUT=$(expect -c '
# To suppress any other form of output generated by spawned process
log_user 0
spawn ssh dinesh#xxx.xxx.xx.xxx
# To match some common prompts. Update it as per your needs.
# To match literal dollar, it is escaped with backslash
set prompt "#|>|\\$"
expect {
eof {puts "Connection rejected by the host"; exit 0}
timeout {puts "Unable to access the host"; exit 0;}
"password:"
}
send "root\r"
expect {
timeout {puts "Unable to access the host"; exit 0;}
-re $prompt
}
send "date\r"
# Matching only the date cmd output alone
expect {
timeout { puts "Unable to access the host";exit 0}
-re "\n(\[^\r]*)\r"
}
send_user "$expect_out(1,string)\n"
exit 1
')
echo "Expect's return value: $?"; # Printing value returned from 'Expect'
echo "Expect Output: $OUTPUT"
Output:
dinesh#MyPC:~/stackoverflow$ ./Meric
Expect's return value: 1
Expect Output: Wed Sep 2 09:35:14 IST 2015
dinesh#MyPC:~/stackoverflow$
I am trying to call a shell script and store the result in an expect variable. get_pw.sh accepts 2 args and decrypts the file using the provided md5hash. If I execute ./get_pw.sh file.test md5hash from the bash prompt it returns the password string as expected. When called from expect, the password does not get returned. The expect debug shows:
expect: does "" (spawn_id exp0) match regular expression "[^\s]"?
So it looks like the script is not returning the password string when called from expect. Relevant code:
#!/usr/bin/expect
send "./get_pw.sh file.test md5hash \r"
expect -re {[^\s]} {
set password $expect_out(0,string)
}
puts "The password is: $password"
You need to spawn a command first before you can send input and expect output from it.
To set an expect variable to the output of a command, use
set varname [exec command]
If you must do this with expect,
log_user 0
spawn -noecho get_pw.sh file hash
expect eof
set passwd [string trimright $expect_out(buffer) "\r\n"]
puts $passwd
Jens's answer looks pretty good by now ...
I have a bash+expect script which has to connect via ssh to the remote comp (and i can't use ssh keys, need password identification in here), read the file there, find specific line with the "hostname" (like "hostname aaaa1111") and store this hostname into the variable to be used after while. How can i get the value of the "hostname" parameter? I thought that line content will be in $expect_out(buffer) variable (so i can scan it and analyze), but it's not. My script is:
#!/bin/bash
----bash part----
/usr/bin/expect << ENDOFEXPECT
spawn bash -c "ssh root#$IP"
expect "password:"
send "xxxx\r"
expect ":~#"
send "cat /etc/rc.d/rc.local |grep hostname \r"
expect ":~#"
set line $expect_out(buffer)
puts "line = $line, expect_out(buffer) = $expect_out(buffer)"
...more script...
ENDOFEXPECT
When i try to see line variable, i see only this: line = , expect_out(buffer) = (buffer) What is the right way to get the line from the file into the variable?
Or is it possible to open the file on the remote computer with expect, scan the file and get what i need to the variable?
Here http://en.wikipedia.org/wiki/Expect there is an example:
# Send the prebuilt command, and then wait for another shell prompt.
send "$my_command\r"
expect "%"
# Capture the results of the command into a variable. This can be displayed,
set results $expect_out(buffer)
seems that it doesn't work in this case?
You might just want to try and do it all from expect, as expect can control bash.
The following should do what you've described. Not sure if this is exactly what you are trying to do.
#!/bin/sh
# the next line restarts using tclsh \
exec expect "$0" "$#"
spawn bash
send "ssh root#$IP\r"
expect "password:"
send "xxxx\r"
expect ":~#"
send "cat /etc/rc.d/rc.local |grep hostname \n"
expect ":~#"
set extractedOutput $expect_out(buffer)
set list [split $extractedOutput "\n"]
foreach line $list {
set re {(?x)
.*
(*)
-S.*
}
regexp $re $line total extractedValue
if {[info exists extractedValue] && [string length $extractedValue] > 1} {
set exportValue $extractedValue
break # We've got a match!
}
send "exit\r" # disconnect from the ssh session
if {[info exists exportValue] && [string length $exportValue] > 1}{
send "export VARIABLE $exportValue\r"
} else {
send_user "No exportValue was found - exiting\n"
send "exit\r"
close
exit 1
}
# now you can do more things in bash if you like
I am using expect within bash. I want my script to telnet into a box, expect a prompt, send a command. If there is a different prompt now, it has to proceed or else it has to send that command again.
My script goes like this:
\#!bin/bash
//I am filling up IP and PORT1 here
expect -c "
set timeout -1
spawn telnet $IP $PORT1
sleep 1
send \"\r\"
send \"\r\"
set temp 1
while( $temp == 1){
expect {
Prompt1 { send \"command\" }
Prompt2 {send \"Yes\"; set done 0}
}
}
"
Output:
invalid command name "while("
while executing
"while( == 1){"
Kindly help me.
I tried to change it to while [ $temp == 1] {
I am still facing the error below:
Output:
invalid command name "=="
while executing
"== 1"
invoked from within
"while [ == 1] {
expect {
This is how I'd implement this:
expect -c '
set timeout -1
spawn telnet [lindex $argv 0] [lindex $argv 1]
send "\r"
send "\r"
expect {
Prompt1 {
send "command"
exp_continue
}
Prompt2 {
send "Yes\r"
}
}
}
' $IP $PORT1
use single quotes around the expect script to protect expect variables
pass the shell variables as arguments to the script.
use "exp_continue" to loop instead of an explicit while loop (you had the wrong terminating variable name anyway)
The syntax for while is "while test body". There must be a spce between each of those parts which is why you get the error "no such command while)"
Also, because of tcl quoting rules, 99.99% of the time the test needs to be in curly braces. So, the syntax is:
while {$temp == 1} {
For more information see http://tcl.tk/man/tcl8.5/TclCmd/while.htm
(you probably have other problems related to your choice of shell quotes; this answer addresses your specific question about the while statement)