Module: Rex::Socket::Udp

Includes:
Rex::Socket
Included in:
Post::Meterpreter::Extensions::Stdapi::Net::SocketSubsystem::UdpChannel
Defined in:
lib/rex/socket/udp.rb

Overview

This class provides methods for interacting with a UDP socket.

Constant Summary

Constants included from Rex::Socket

MATCH_IPV4, MATCH_IPV4_PRIVATE, MATCH_IPV6

Instance Attribute Summary

Attributes included from Rex::Socket

#context, #ipv, #localhost, #localport, #peerhost, #peerport

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Rex::Socket

addr_atoc, addr_atoi, addr_atoi_list, addr_aton, addr_ctoa, addr_itoa, addr_iton, addr_ntoa, addr_ntoi, bit2netmask, cidr_crack, compress_address, create_ip, create_tcp, create_tcp_server, create_udp, dotted_ip?, eth_aton, eth_ntoa, #fd, from_sockaddr, getaddress, getaddresses, gethostbyname, #getlocalname, #getpeername, #getsockname, #initsock, ipv6_link_address, ipv6_mac, is_internal?, is_ipv4?, is_ipv6?, net2bitmask, portlist_to_portspec, portspec_crack, portspec_to_portlist, resolv_nbo, resolv_nbo_i, resolv_nbo_i_list, resolv_nbo_list, resolv_to_dotted, source_address, support_ipv6?, tcp_socket_pair, to_sockaddr, udp_socket_pair

Class Method Details

.create(hash = {}) ⇒ Object

Creates the client using the supplied hash.


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# File 'lib/rex/socket/udp.rb', line 22

def self.create(hash = {})
  hash['Proto'] = 'udp'
  # If we have are to bind to a LocalHost we must be a Server to avail of pivoting.
  # Rex::Socket::Parameters will subsequently turn off the sever flag after the correct
  # comm has been chosen.
  if( hash['LocalHost'] )
    hash['Server'] = true
  end
  self.create_param(Rex::Socket::Parameters.from_hash(hash))
end

.create_param(param) ⇒ Object

Wrapper around the base socket class' creation method that automatically sets the parameter's protocol to UDP.


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# File 'lib/rex/socket/udp.rb', line 37

def self.create_param(param)
  param.proto = 'udp'
  Rex::Socket.create_param(param)
end

Instance Method Details

#def_read_timeoutObject

The default number of seconds to wait for a read operation to timeout.


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# File 'lib/rex/socket/udp.rb', line 156

def def_read_timeout
  10
end

#get(timeout = nil) ⇒ Object

Calls recvfrom and only returns the data


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# File 'lib/rex/socket/udp.rb', line 148

def get(timeout=nil)
  data, saddr, sport = recvfrom(65535, timeout)
  return data
end

#read(length = 65535) ⇒ Object

Read a datagram from the UDP socket.


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# File 'lib/rex/socket/udp.rb', line 64

def read(length = 65535)
  if length < 0
    length = 65535
  end
  return sysread(length)
end

#recvfrom(length = 65535, timeout = def_read_timeout) ⇒ Object

Receives a datagram and returns the data and host:port of the requestor as [ data, host, port ].


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# File 'lib/rex/socket/udp.rb', line 123

def recvfrom(length = 65535, timeout=def_read_timeout)

  begin
    if ((rv = ::IO.select([ fd ], nil, nil, timeout)) and
        (rv[0]) and (rv[0][0] == fd)
       )
        data, saddr    = recvfrom_nonblock(length)
        af, host, port = Rex::Socket.from_sockaddr(saddr)

        return [ data, host, port ]
    else
      return [ '', nil, nil ]
    end
  rescue ::Timeout::Error
    return [ '', nil, nil ]
  rescue ::Interrupt
    raise $!
  rescue ::Exception
    return [ '', nil, nil ]
  end
end

#sendto(gram, peerhost, peerport, flags = 0) ⇒ Object

Sends a datagram to the supplied host:port with optional flags.


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# File 'lib/rex/socket/udp.rb', line 100

def sendto(gram, peerhost, peerport, flags = 0)

  # Catch unconnected IPv6 sockets talking to IPv4 addresses
  peer = Rex::Socket.resolv_nbo(peerhost)
  if (peer.length == 4 and self.ipv == 6)
    peerhost = Rex::Socket.getaddress(peerhost, true)
    if peerhost[0,7].downcase != '::ffff:'
      peerhost = '::ffff:' + peerhost
    end
  end

  begin
    send(gram, flags, Rex::Socket.to_sockaddr(peerhost, peerport))
  rescue  ::Errno::EHOSTUNREACH,::Errno::ENETDOWN,::Errno::ENETUNREACH,::Errno::ENETRESET,::Errno::EHOSTDOWN,::Errno::EACCES,::Errno::EINVAL,::Errno::EADDRNOTAVAIL
    return nil
  end

end

#timed_read(length = 65535, timeout = def_read_timeout) ⇒ Object

Read a datagram from the UDP socket with a timeout


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# File 'lib/rex/socket/udp.rb', line 74

def timed_read(length = 65535, timeout=def_read_timeout)
  begin
    if ((rv = ::IO.select([ fd ], nil, nil, timeout)) and
        (rv[0]) and (rv[0][0] == fd)
       )
        return read(length)
    else
      return ''
    end
  rescue Exception
    return ''
  end
end

#type?Boolean

Returns:

  • (Boolean)

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# File 'lib/rex/socket/udp.rb', line 160

def type?
  return 'udp'
end

#write(gram) ⇒ Object Also known as: put

Write the supplied datagram to the connected UDP socket.


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# File 'lib/rex/socket/udp.rb', line 51

def write(gram)
  begin
    return syswrite(gram)
  rescue  ::Errno::EHOSTUNREACH,::Errno::ENETDOWN,::Errno::ENETUNREACH,::Errno::ENETRESET,::Errno::EHOSTDOWN,::Errno::EACCES,::Errno::EINVAL,::Errno::EADDRNOTAVAIL
    return nil
  end
end