Example of monitoring SSH running reverse forward

Run it as another user. For example, the user name is "user"

#! /Bin/KSh
Su-user-S/bin/KSh "/home/ssh_monitor.sh $ *"

 

Ssh_monitor.sh:

#! /Bin/KSh

###### Config ########
Logfile = "./ssh_admin.log"
Known_hosts = "/home/user/. Ssh/known_hosts"
Ssh_pid = '0'
Break_out = 'n'

State_key_string = 'established'
Hasuserconnected = 0

########## SSH forward ##########
Ssh_port = '22'
Remote_host = '192. 168.1.142'
Remote_http_port = '123'
User_name = 'user'
Total_seconds = 600
############ End ################

Isclientexit ()
{
# Echo "Enter isclientexit"

# Is the tunnel up? Perform Two tests:

#1. Check for relevant process ($ command)
# Pgrep-F-X "$ command">/dev/null 2> & 1 | $ command

#2. Test Tunnel by looking at "netstat" output on $ remote_host

Echo "ssh-p $ ssh_port $ user_name @ $ remote_host netstat-an | egrep \" TCP. *: $ remote_http_port. * $ state_key_string \ "| WC-l"

Num = $ (ssh-p $ ssh_port $ user_name @ $ remote_host netstat-an | egrep "TCP. *: $ remote_http_port. * $ state_key_string" | WC-l )\

>/Dev/null 2> & 1

If (hasuserconnected = 1 & num = 0 ))
Then
Echo "client has exited." >>$ logfile
Break_out = 'y'

Elif (num! = 0 & hasuserconnected = 0 ))
Then

Echo "client has connected." >>$ logfile
Hasuserconnected = 1

Fi
}

Trap_exit ()
{
Print "Enter trap_exit" >>$ logfile
# Post_event_script
Break_out = 'y'
}

Post_event_script ()
{
Print "Enter post_event_script"> $ logfile
# Ps-Ef | grep "ssh" | grep-V grep | awk '{print $2}' | read kill_pids
# Echo $ kill_pids
Echo "Kill-9 $ {ssh_pid}" >>$ logfile
Kill-9 "$ ssh_pid"
Ssh-keygen-r $ remote_host
Return 0
}

################
# Start of main #
################

Trap 'trap _ exit '1 2 3 15

[[! -S $ logfile] & touch $ logfile
[[! -S $ known_hosts] & touch $ known_hosts

Echo "###################################### ########### "> $ logfile
Echo "ssh tunnel start." >>$ logfile
Echo "Wait..." >>$ logfile

######### Process paramter ############
Echo $ *
While getopts ": P: U: R: O:" Arg # The colon following the option indicates that parameters are required for this option.
Do
Case $ ARG in
P)
Remote_http_port = $ optarg
;;
U)
User_name = $ optarg
;;
R)
Remote_host = $ optarg
;;

O)
Total_seconds = $ optarg
;;
?) # When there are unrecognized options, What Is Arg?
Echo "unkonw argument"
Exit 1
;;
Esac
Done

Echo "++"
Echo $ remote_host
Echo $ user_name
Echo $ remote_http_port
Echo $ total_seconds
Echo "++"

Echo $ Shell

# Ssh-P 22003 user@127.0.0.1
# Echo "ssh-r 2200:127. 0.0.1: 22-N user@192.168.1.142"
# $ Command is the command used to create the reverse SSH Tunnel
Command = "ssh-o" \ '"stricthostkeychecking no" \' "-p $ ssh_port-Q-n-r $ remote_host: $ remote_http_port: 127.0.0.1: $ ssh_port $ user_name @ $ remote_host"
Echo $ command
Ksh "$ command" | & amp &#????? 'Stricthostkeychecking no' has no method to make it legal.
# Ssh-O 'stricthostkeychecking no'-p $ ssh_port-Q-n-r $ remote_host: $ remote_http_port: 127.0.0.1: $ ssh_port $ user_name @ $ remote_host &
Ssh_pid = $!
Echo "ssh PID: $ {ssh_pid}" >>$ logfile

Until (total_seconds = 0 ))
Do
Isclientexit
Echo $ break_out
If [[$ break_out = 'y']
Then
Break
Fi

(Total_seconds = total_seconds-1 ))
Sleep 1
# Echo "after sleep 1 s"
# Echo "$ total_seconds"
Done

# Kill all SSH and-R;
Post_event_script

Exit 0