metasploit-framework/lib/net/ssh/proxy/socks4.rb

83 lines
2.5 KiB
Ruby

# -*- coding: binary -*-
require 'rex/socket'
require 'resolv'
require 'ipaddr'
require 'net/ssh/proxy/errors'
module Net
module SSH
module Proxy
# An implementation of a SOCKS4 proxy. To use it, instantiate it, then
# pass the instantiated object via the :proxy key to Net::SSH.start:
#
# require 'net/ssh/proxy/socks4'
#
# proxy = Net::SSH::Proxy::SOCKS4.new('proxy.host', proxy_port, :user => 'user')
# Net::SSH.start('host', 'user', :proxy => proxy) do |ssh|
# ...
# end
class SOCKS4
# The SOCKS protocol version used by this class
VERSION = 4
# The packet type for connection requests
CONNECT = 1
# The status code for a successful connection
GRANTED = 90
# The proxy's host name or IP address, as given to the constructor.
attr_reader :proxy_host
# The proxy's port number.
attr_reader :proxy_port
# The additional options that were given to the proxy's constructor.
attr_reader :options
# Create a new proxy connection to the given proxy host and port.
# Optionally, a :user key may be given to identify the username
# with which to authenticate.
def initialize(proxy_host, proxy_port=1080, options={})
@proxy_host = proxy_host
@proxy_port = proxy_port
@options = options
end
# Return a new socket connected to the given host and port via the
# proxy that was requested when the socket factory was instantiated.
def open(host, port)
socket = Rex::Socket::Tcp.create(
'PeerHost' => proxy_host,
'PeerPort' => proxy_port,
'Context' => {
'Msf' => options[:msframework],
'MsfExploit' => options[:msfmodule]
}
)
# Tell MSF to automatically close this socket on error or completion...
# This prevents resource leaks.
options[:msfmodule].add_socket(@socket) if options[:msfmodule]
ip_addr = IPAddr.new(Resolv.getaddress(host))
packet = [VERSION, CONNECT, port.to_i, ip_addr.to_i, options[:user]].pack("CCnNZ*")
socket.send packet, 0
version, status, port, ip = socket.recv(8).unpack("CCnN")
if status != GRANTED
socket.close
raise ConnectError, "error connecting to proxy (#{status})"
end
return socket
end
end
end
end
end