module EventMachine::Socksify::SOCKS5

Public Instance Methods

socks_send_authentication() click to toggle source
# File lib/em-socksify/socks5.rb, line 33
def socks_send_authentication
  @socks_state = :authenticating

  send_data [5,
             @socks_username.length, @socks_username,
             @socks_password.length, @socks_password
             ].pack('CCA*CA*')
end
socks_send_connect_request() click to toggle source
# File lib/em-socksify/socks5.rb, line 15
def socks_send_connect_request
  @socks_state = :connecting

  send_data [5, 1, 0].pack('CCC')

  if matches = @socks_target_host.match(/^(\d+)\.(\d+)\.(\d+)\.(\d+)$/)
    send_data "\x01" + matches.to_a[1 .. -1].map { |s| s.to_i }.pack('CCCC')

  elsif @socks_target_host =~ /^[:0-9a-f]+$/
    raise SOCKSError, 'TCP/IPv6 over SOCKS is not yet supported (inet_pton missing in Ruby & not supported by Tor)'

  else
    send_data [3, @socks_target_host.size, @socks_target_host].pack('CCA*')
  end

  send_data [@socks_target_port].pack('n')
end
socks_send_handshake() click to toggle source
# File lib/em-socksify/socks5.rb, line 5
def socks_send_handshake
  # Method Negotiation as described on
  # http://www.faqs.org/rfcs/rfc1928.html Section 3
  @socks_state = :method_negotiation

  socks_methods.tap do |methods|
    send_data [5, methods.size].pack('CC') + methods.pack('C*')
  end
end

Private Instance Methods

socks_methods() click to toggle source
# File lib/em-socksify/socks5.rb, line 107
def socks_methods
  methods = []
  methods << 2 if !@socks_username.nil? # 2 => Username/Password Authentication
  methods << 0 # 0 => No Authentication Required

  methods
end
socks_parse_response() click to toggle source

parses socks 5 server responses as specified on www.faqs.org/rfcs/rfc1928.html

# File lib/em-socksify/socks5.rb, line 46
def socks_parse_response
  case @socks_state
  when :method_negotiation
    return unless @socks_data.size >= 2

    _, method = @socks_data.slice!(0, 2).unpack('CC')

    if socks_methods.include?(method)
      case method
      when 0 then socks_send_connect_request
      when 2 then socks_send_authentication
      end
    else
      raise SOCKSError, 'proxy did not accept method'
    end

  when :authenticating
    return unless @socks_data.size >= 2

    socks_version, status_code = @socks_data.slice!(0, 2).unpack('CC')

    raise SOCKSError, "SOCKS version 5 not supported" unless socks_version == 5
    raise SOCKSError, 'access denied by proxy'        unless status_code == 0

    send_socks_connect_request

  when :connecting
    return unless @socks_data.size >= 2

    socks_version, status_code = @socks_data.slice(0, 2).unpack('CC')

    raise SOCKSError, "SOCKS version #{socks_version} is not 5" unless socks_version == 5
    raise SOCKSError.for_response_code(status_code)             unless status_code == 0

    min_size = @socks_data[3].ord == 3 ? 5 : 4

    return unless @socks_data.size >= min_size

    size = case @socks_data[3].ord
    when 1 then 4
    when 3 then @socks_data[4].ord
    when 4 then 16
    else raise SOCKSError.for_response_code(@socks_data[3])
    end

    return unless @socks_data.size >= (min_size + size)

    bind_addr = @socks_data.slice(min_size, size)

    ip = case @socks_data[3].ord
    when 1 then bind_addr.bytes.to_a.join('.')
    when 3 then bind_addr
    when 4 then # TODO: ???
    end

    socks_unhook(ip)
  end
rescue Exception => e
  @socks_deferrable.fail(e)
end