Module: Rex::Socket

Included in:
Proto::DHCP::Server, Ip, Tcp, TcpServer, Udp
Defined in:
lib/rex/socket.rb,
lib/rex/socket/comm.rb,
lib/rex/socket/range_walker.rb,
lib/rex/socket/switch_board.rb,
lib/rex/socket/subnet_walker.rb

Overview

Base class for all sockets.

Defined Under Namespace

Modules: Comm, Ip, SslTcp, SslTcpServer, Tcp, TcpServer, Udp Classes: Parameters, Range, RangeWalker, SubnetWalker, SwitchBoard, UnitTest

Constant Summary collapse

@@support_ipv6 =

Cache our IPv6 support flag

nil

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#contextObject

Contextual information that describes the source and other instance-specific attributes. This comes from the param.context attribute.



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# File 'lib/rex/socket.rb', line 665

def context
  @context
end

#ipvObject

The IP version of the socket



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# File 'lib/rex/socket.rb', line 659

def ipv
  @ipv
end

#localhostObject

The local host of the connected socket.



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# File 'lib/rex/socket.rb', line 651

def localhost
  @localhost
end

#localportObject

The local port of the connected socket.



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# File 'lib/rex/socket.rb', line 655

def localport
  @localport
end

#peerhostObject

The peer host of the connected socket.



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# File 'lib/rex/socket.rb', line 643

def peerhost
  @peerhost
end

#peerportObject

The peer port of the connected socket.



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# File 'lib/rex/socket.rb', line 647

def peerport
  @peerport
end

Class Method Details

.addr_atoc(mask) ⇒ Object

Converts an ASCII IP address to a CIDR mask. Returns nil if it’s not convertable.



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# File 'lib/rex/socket.rb', line 242

def self.addr_atoc(mask)
	mask_i = resolv_nbo_i(mask)
	cidr = nil
	0.upto(32) do |i|
		if ((1 << i)-1) << (32-i) == mask_i
			cidr = i
			break
		end
	end
	return cidr
end

.addr_atoi(addr) ⇒ Object

Converts a ascii address into an integer



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# File 'lib/rex/socket.rb', line 273

def self.addr_atoi(addr)
	resolv_nbo_i(addr)
end

.addr_aton(addr) ⇒ Object

Converts a ascii address to network byte order



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# File 'lib/rex/socket.rb', line 296

def self.addr_aton(addr)
	resolv_nbo(addr)
end

.addr_ctoa(cidr) ⇒ Object

Resolves a CIDR bitmask into a dotted-quad. Returns nil if it’s not convertable.



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# File 'lib/rex/socket.rb', line 258

def self.addr_ctoa(cidr)
	return nil unless (0..32) === cidr.to_i
	addr_itoa(((1 << cidr)-1) << 32-cidr)
end

.addr_itoa(addr, v6 = false) ⇒ Object

Converts an integer address into ascii



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# File 'lib/rex/socket.rb', line 280

def self.addr_itoa(addr, v6=false)

	nboa = addr_iton(addr, v6)

	# IPv4
	if (addr < 0x100000000 and not v6)
		nboa.unpack('C4').join('.')
	# IPv6
	else
		nboa.unpack('n8').map{ |c| "%.4x" % c }.join(":")
	end
end

.addr_iton(addr, v6 = false) ⇒ Object

Converts an integer into a network byte order address



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# File 'lib/rex/socket.rb', line 341

def self.addr_iton(addr, v6=false)
	if(addr < 0x100000000 and not v6)
		return [addr].pack('N')
	else
		w    = []
		w[0] = (addr >> 96) & 0xffffffff
		w[1] = (addr >> 64) & 0xffffffff
		w[2] = (addr >> 32) & 0xffffffff
		w[3] = addr & 0xffffffff
		return w.pack('N4')
	end
end

.addr_ntoa(addr) ⇒ Object

Converts a network byte order address to ascii

Raises:



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# File 'lib/rex/socket.rb', line 303

def self.addr_ntoa(addr)

	# IPv4
	if (addr.length == 4)
		return addr.unpack('C4').join('.')
	end

	# IPv6
	if (addr.length == 16)
		return addr.unpack('n8').map{ |c| "%.4x" % c }.join(":")
	end

	raise RuntimeError, "Invalid address format"
end

.addr_ntoi(addr) ⇒ Object

Converts a network byte order address to an integer

Raises:



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# File 'lib/rex/socket.rb', line 321

def self.addr_ntoi(addr)

	bits = addr.unpack("N*")

	if (bits.length == 1)
		return bits[0]
	end

	if (bits.length == 4)
		val = 0
		bits.each_index { |i| val += (  bits[i] << (96 - (i * 32)) ) }
		return val
	end

	raise RuntimeError, "Invalid address format"
end

.bit2netmask(bitmask) ⇒ Object

Converts a bitmask (28) into a netmask (255.255.255.240) TODO: IPv6 (use is ambiguous right now)



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# File 'lib/rex/socket.rb', line 408

def self.bit2netmask(bitmask)
	[ (~((2 ** (32 - bitmask)) - 1)) & 0xffffffff ].pack('N').unpack('CCCC').join('.')
end

.cidr_crack(cidr, v6 = false) ⇒ Object

Converts a CIDR subnet into an array (base, bcast)



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# File 'lib/rex/socket.rb', line 357

def self.cidr_crack(cidr, v6=false)
	tmp = cidr.split('/')

	tst,scope = tmp[0].split("%",2)
	scope     = "%" + scope if scope
	scope   ||= ""

	addr = addr_atoi(tst)

	bits = 32
	mask = 0
	use6 = false

	if (addr > 0xffffffff or v6 or cidr =~ /:/)
		use6 = true
		bits = 128
	end

	mask = (2 ** bits) - (2 ** (bits - tmp[1].to_i))
	base = addr & mask

	stop = base + (2 ** (bits - tmp[1].to_i)) - 1
	return [self.addr_itoa(base, use6) + scope, self.addr_itoa(stop, use6) + scope]
end

.create(opts = {}) ⇒ Object

Create a socket instance using the supplied parameter hash.



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# File 'lib/rex/socket.rb', line 38

def self.create(opts = {})
	return create_param(Rex::Socket::Parameters.from_hash(opts))
end

.create_ip(opts = {}) ⇒ Object

Create a IP socket using the supplied parameter hash.



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# File 'lib/rex/socket.rb', line 73

def self.create_ip(opts = {})
	return create_param(Rex::Socket::Parameters.from_hash(opts.merge('Proto' => 'ip')))
end

.create_param(param) ⇒ Object

Create a socket using the supplied Rex::Socket::Parameter instance.



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# File 'lib/rex/socket.rb', line 45

def self.create_param(param)
	return param.comm.create(param)
end

.create_tcp(opts = {}) ⇒ Object

Create a TCP socket using the supplied parameter hash.



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# File 'lib/rex/socket.rb', line 52

def self.create_tcp(opts = {})
	return create_param(Rex::Socket::Parameters.from_hash(opts.merge('Proto' => 'tcp')))
end

.create_tcp_server(opts = {}) ⇒ Object

Create a TCP server socket using the supplied parameter hash.



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# File 'lib/rex/socket.rb', line 59

def self.create_tcp_server(opts = {})
	return create_tcp(opts.merge('Server' => true))
end

.create_udp(opts = {}) ⇒ Object

Create a UDP socket using the supplied parameter hash.



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# File 'lib/rex/socket.rb', line 66

def self.create_udp(opts = {})
	return create_param(Rex::Socket::Parameters.from_hash(opts.merge('Proto' => 'udp')))
end

.dotted_ip?(addr) ⇒ Boolean

Checks to see if the supplied address is a dotted quad.

Returns:

  • (Boolean)


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# File 'lib/rex/socket.rb', line 126

def self.dotted_ip?(addr)
	# Assume anything with a colon is IPv6
	return true if (support_ipv6? and addr =~ /:/)

	# Otherwise assume this is IPv4
	(addr =~ /^(?:(?:25[0-5]|2[0-4][0-9]|[0-1]?[0-9]{1,2})[.](?:25[0-5]|2[0-4][0-9]|[0-1]?[0-9]{1,2})[.](?:25[0-5]|2[0-4][0-9]|[0-1]?[0-9]{1,2})[.](?:25[0-5]|2[0-4][0-9]|[0-1]?[0-9]{1,2}))$/) ? true : false
end

.from_sockaddr(saddr) ⇒ Object

Returns the address family, host, and port of the supplied sockaddr as

af, host, port


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# File 'lib/rex/socket.rb', line 215

def self.from_sockaddr(saddr)
	port, host = ::Socket::unpack_sockaddr_in(saddr)
	af = ::Socket::AF_INET
	if (support_ipv6?() and is_ipv6?(host))
		af = ::Socket::AF_INET6
	end
	return [ af, host, port ]
end

.getaddress(addr, accept_ipv6 = true) ⇒ Object

Wrapper for Resolv.getaddress that takes special care to see if the supplied address is already a dotted quad, for instance. This is necessary to prevent calls to gethostbyaddr (which occurs on windows). These calls can be quite slow. This also fixes an issue with the Resolv.getaddress() call being non-functional on Ruby 1.9.1 (Win32).



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# File 'lib/rex/socket.rb', line 153

def self.getaddress(addr, accept_ipv6 = true)
	begin
		if dotted_ip?(addr)
			return addr
		end

		res = ::Socket.gethostbyname(addr)
		return nil if not res

		# Shift the first three elements out
		rname  = res.shift
		ralias = res.shift
		rtype  = res.shift

		# Reject IPv6 addresses if we don't accept them
		if not accept_ipv6
			res.reject!{|nbo| nbo.length != 4}
		end

		# Make sure we have at least one name
		return nil if res.length == 0

		# Return the first address of the result
		self.addr_ntoa( res[0] )
	rescue ::ArgumentError # Win32 bug
		nil
	end
end

.gethostbyname(host) ⇒ Object

Wrapper for Socket.gethostbyname which takes into account whether or not an IP address is supplied. If it is, then reverse DNS resolution does not occur. This is done in order to prevent delays, such as would occur on Windows.



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# File 'lib/rex/socket.rb', line 188

def self.gethostbyname(host)
	if (dotted_ip?(host))
		if (is_ipv4?(host))
			return [ host, host, 2, host.split('.').map{ |c| c.to_i }.pack("C4") ]
		end
	end

	::Socket.gethostbyname(host)
end

Identifies the link-local address of a given interface (if IPv6 is enabled)



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# File 'lib/rex/socket.rb', line 504

def self.ipv6_link_address(intf)
	r = source_address("FF02::1%#{intf}")
	return if not (r and r =~ /^fe80/i)
	r
end

.ipv6_mac(intf) ⇒ Object

Identifies the mac address of a given interface (if IPv6 is enabled)



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# File 'lib/rex/socket.rb', line 513

def self.ipv6_mac(intf)
	r = ipv6_link_address(intf)
	return if not r
	raw = addr_aton(r)[-8, 8]
	(raw[0,3] + raw[5,3]).unpack("C*").map{|c| "%.2x" % c}.join(":")
end

.is_internal?(addr) ⇒ Boolean

Return true if addr is within the ranges specified in RFC1918, or RFC5735/RFC3927

Returns:

  • (Boolean)


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# File 'lib/rex/socket.rb', line 138

def self.is_internal?(addr)
	if self.dotted_ip?(addr)
		addr =~ /^(?:10\.|192\.168|172.(?:1[6-9]|2[0-9]|3[01])\.|169\.254)/
	else
		false
	end
end

.is_ipv4?(addr) ⇒ Boolean

Determine whether this is an IPv4 address

Returns:

  • (Boolean)


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# File 'lib/rex/socket.rb', line 110

def self.is_ipv4?(addr)
	res = Rex::Socket.getaddress(addr)
	res.match(/:/) ? false : true
end

.is_ipv6?(addr) ⇒ Boolean

Determine whether this is an IPv6 address

Returns:

  • (Boolean)


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# File 'lib/rex/socket.rb', line 118

def self.is_ipv6?(addr)
	res = Rex::Socket.getaddress(addr)
	res.match(/:/) ? true : false
end

.net2bitmask(netmask) ⇒ Object

Converts a netmask (255.255.255.240) into a bitmask (28). This is the lame kid way of doing it.



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# File 'lib/rex/socket.rb', line 386

def self.net2bitmask(netmask)

	nmask = resolv_nbo(netmask)
	imask = addr_ntoi(nmask)
	bits  = 32

	if (imask > 0xffffffff)
		bits = 128
	end

	0.upto(bits-1) do |bit|
		p = 2 ** bit
		return (bits - bit) if ((imask & p) == p)
	end

	0
end

.portlist_to_portspec(parr) ⇒ Object

Converts a port list like [1,2,3,4,5,100] into a range specification like “1-5,100”



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# File 'lib/rex/socket.rb', line 444

def self.portlist_to_portspec(parr)
	ranges = []
	range  = []
	lastp  = nil

	parr.uniq.sort{|a,b| a<=>b}.map{|a| a.to_i}.each do |n|
		next if (n < 1 or n > 65535)
		if not lastp
			range = [n]
			lastp = n
			next
		end

		if lastp == n - 1
			range << n
		else
			ranges << range
			range = [n]
		end
		lastp = n
	end

	ranges << range
	ranges.delete(nil)
	ranges.uniq.map{|x| x.length == 1 ? "#{x[0]}" : "#{x[0]}-#{x[-1]}"}.join(",")
end

.portspec_crack(pspec) ⇒ Object



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# File 'lib/rex/socket.rb', line 413

def self.portspec_crack(pspec)
	portspec_to_portlist(pspec)
end

.portspec_to_portlist(pspec) ⇒ Object

Converts a port specification like “80,21-23,443” into a sorted, unique array of valid port numbers like [21,22,23,80,443]



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# File 'lib/rex/socket.rb', line 421

def self.portspec_to_portlist(pspec)
	ports = []

	# Build ports array from port specification
	pspec.split(/,/).each do |item|
		start, stop = item.split(/-/).map { |p| p.to_i }

		start ||= 0
		stop ||= item.match(/-/) ? 65535 : start

		start, stop = stop, start if stop < start

		start.upto(stop) { |p| ports << p }
	end

	# Sort, and remove dups and invalid ports
	ports.sort.uniq.delete_if { |p| p < 1 or p > 65535 }
end

.resolv_nbo(host) ⇒ Object

Resolves a host to raw network-byte order.



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# File 'lib/rex/socket.rb', line 227

def self.resolv_nbo(host)
	self.gethostbyname(Rex::Socket.getaddress(host))[3]
end

.resolv_nbo_i(host) ⇒ Object

Resolves a host to a network-byte order ruby integer.



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# File 'lib/rex/socket.rb', line 234

def self.resolv_nbo_i(host)
	addr_ntoi(resolv_nbo(host))
end

.resolv_to_dotted(host) ⇒ Object

Resolves a host to a dotted address.



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# File 'lib/rex/socket.rb', line 266

def self.resolv_to_dotted(host)
	addr_ntoa(addr_aton(host))
end

.source_address(dest = '8.8.8.8', comm = ::Rex::Socket::Comm::Local) ⇒ Object

This method does NOT send any traffic to the destination, instead, it uses a “bound” UDP socket to determine what source address we would use to communicate with the specified destination. The destination defaults to Google’s DNS server to make the standard behavior determine which IP we would use to communicate with the internet.



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# File 'lib/rex/socket.rb', line 484

def self.source_address(dest='8.8.8.8', comm = ::Rex::Socket::Comm::Local)
	begin
		s = self.create_udp(
			'PeerHost' => dest,
			'PeerPort' => 31337,
			'Comm'     => comm
		)
		r = s.getsockname[1]
		s.close

		# Trim off the trailing interface ID for link-local IPv6
		return r.split('%').first
	rescue ::Exception
		return '127.0.0.1'
	end
end

.support_ipv6?Boolean

Determine whether we support IPv6

Returns:

  • (Boolean)


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# File 'lib/rex/socket.rb', line 90

def self.support_ipv6?
	return @@support_ipv6 if not @@support_ipv6.nil?

	@@support_ipv6 = false

	if (::Socket.const_defined?('AF_INET6'))
		begin
			s = ::Socket.new(::Socket::AF_INET6, ::Socket::SOCK_DGRAM, ::Socket::IPPROTO_UDP)
			s.close
			@@support_ipv6 = true
		rescue
		end
	end

	return @@support_ipv6
end

.tcp_socket_pairObject

Create a TCP socket pair.

sf: This create a socket pair using native ruby sockets and will work on Windows where ::Socket.pair is not implemented. Note: OpenSSL requires native ruby sockets for its io.

Note: Even though sub-threads are smashing the parent threads local, there

is no concurrent use of the same locals and this is safe.


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# File 'lib/rex/socket.rb', line 529

def self.tcp_socket_pair
	lsock   = nil
	rsock   = nil
	laddr   = '127.0.0.1'
	lport   = 0
	threads = []
	mutex   = ::Mutex.new

	threads << Rex::ThreadFactory.spawn('TcpSocketPair', false) {
		server = nil
		mutex.synchronize {
			threads << Rex::ThreadFactory.spawn('TcpSocketPairClient', false) {
				mutex.synchronize {
					rsock = ::TCPSocket.new( laddr, lport )
				}
			}
			server = ::TCPServer.new(laddr, 0)
			if (server.getsockname =~ /127\.0\.0\.1:/)
				# JRuby ridiculousness
				caddr, lport = server.getsockname.split(":")
				caddr = caddr[1,caddr.length]
				lport = lport.to_i
			else
				# Sane implementations where Socket#getsockname returns a
				# sockaddr
				lport, caddr = ::Socket.unpack_sockaddr_in( server.getsockname )
			end
		}
		lsock, saddr = server.accept
		server.close
	}

	threads.each { |t| t.join }

	return [lsock, rsock]
end

.to_sockaddr(ip, port) ⇒ Object

Create a sockaddr structure using the supplied IP address, port, and address family



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# File 'lib/rex/socket.rb', line 202

def self.to_sockaddr(ip, port)

	if (ip == '::ffff:0.0.0.0')
		ip = support_ipv6?() ? '::' : '0.0.0.0'
	end

	return ::Socket.pack_sockaddr_in(port, ip)
end

.udp_socket_pairObject

Create a UDP socket pair using native ruby UDP sockets.



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# File 'lib/rex/socket.rb', line 569

def self.udp_socket_pair
	laddr = '127.0.0.1'

	lsock = ::UDPSocket.new
	lsock.bind( laddr, 0 )

	rsock = ::UDPSocket.new
	rsock.bind( laddr, 0 )

	rsock.connect( *lsock.addr.values_at(3,1) )

	lsock.connect( *rsock.addr.values_at(3,1) )

	return [lsock, rsock]
end

Instance Method Details

#fdObject

By default, all sockets are themselves selectable file descriptors.



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# File 'lib/rex/socket.rb', line 608

def fd
	self
end

#getlocalnameObject

Wrapper around getsockname



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# File 'lib/rex/socket.rb', line 622

def getlocalname
	getsockname
end

#getpeernameObject

Return peer connection information.



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# File 'lib/rex/socket.rb', line 629

def getpeername
	return Socket.from_sockaddr(super)
end

#getsocknameObject

Returns local connection information.



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# File 'lib/rex/socket.rb', line 615

def getsockname
	Socket.from_sockaddr(super)
end

#initsock(params = nil) ⇒ Object

Initialize general socket parameters.



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# File 'lib/rex/socket.rb', line 594

def initsock(params = nil)
	if (params)
		self.peerhost  = params.peerhost
		self.peerport  = params.peerport
		self.localhost = params.localhost
		self.localport = params.localport
		self.context   = params.context || {}
		self.ipv       = params.v6 ? 6 : 4
	end
end

#type?Boolean

Returns a string that indicates the type of the socket, such as ‘tcp’.

Returns:

  • (Boolean)

Raises:



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# File 'lib/rex/socket.rb', line 636

def type?
	raise NotImplementedError, "Socket type is not supported."
end