Module: Rex::Socket

Included in:
Ip, Sctp, SctpServer, Tcp, TcpServer, Udp
Defined in:
lib/rex/socket.rb,
lib/rex/socket/comm.rb,
lib/rex/socket/version.rb,
lib/rex/socket/ssh_factory.rb,
lib/rex/socket/range_walker.rb,
lib/rex/socket/switch_board.rb,
lib/rex/socket/subnet_walker.rb,
lib/rex/socket/x509_certificate.rb

Overview

Base class for all sockets.

Defined Under Namespace

Modules: Comm, Ip, Sctp, SctpServer, Ssl, SslTcp, SslTcpServer, Tcp, TcpServer, Udp Classes: Host, Parameters, Range, RangeWalker, SSHFactory, SubnetWalker, SwitchBoard, X509Certificate

Constant Summary collapse

LogSource = 
'rex-socket'
MATCH_IPV6 =

Common Regular Expressions

/^\s*((([0-9A-Fa-f]{1,4}:){7}([0-9A-Fa-f]{1,4}|:))|(([0-9A-Fa-f]{1,4}:){6}(:[0-9A-Fa-f]{1,4}|((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3})|:))|(([0-9A-Fa-f]{1,4}:){5}(((:[0-9A-Fa-f]{1,4}){1,2})|:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3})|:))|(([0-9A-Fa-f]{1,4}:){4}(((:[0-9A-Fa-f]{1,4}){1,3})|((:[0-9A-Fa-f]{1,4})?:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(([0-9A-Fa-f]{1,4}:){3}(((:[0-9A-Fa-f]{1,4}){1,4})|((:[0-9A-Fa-f]{1,4}){0,2}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(([0-9A-Fa-f]{1,4}:){2}(((:[0-9A-Fa-f]{1,4}){1,5})|((:[0-9A-Fa-f]{1,4}){0,3}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(([0-9A-Fa-f]{1,4}:){1}(((:[0-9A-Fa-f]{1,4}){1,6})|((:[0-9A-Fa-f]{1,4}){0,4}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(:(((:[0-9A-Fa-f]{1,4}){1,7})|((:[0-9A-Fa-f]{1,4}){0,5}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:)))(%.+)?\s*$/
MATCH_IPV4 = 
/^\s*(?:(?:25[0-5]|2[0-4][0-9]|[0-1]?[0-9]{1,2})[.](?:25[0-5]|2[0-4][0-9]|[0-1]?[0-9]{1,2})[.](?:25[0-5]|2[0-4][0-9]|[0-1]?[0-9]{1,2})[.](?:25[0-5]|2[0-4][0-9]|[0-1]?[0-9]{1,2}))\s*$/
MATCH_IPV4_PRIVATE = 
/^\s*(?:10\.|192\.168|172.(?:1[6-9]|2[0-9]|3[01])\.|169\.254)/
MATCH_MAC_ADDR = 
/^(?:[[:xdigit:]]{2}([-:]))(?:[[:xdigit:]]{2}\1){4}[[:xdigit:]]{2}$/
VERSION = 
"0.1.52"
@@support_ipv6 =

Cache our IPv6 support flag

nil

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#context ⇒ Object

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 839

def context
  @context
end

#ipv ⇒ Object

The IP version of the socket



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# File 'lib/rex/socket.rb', line 833

def ipv
  @ipv
end

#localhost ⇒ Object

The local host of the connected socket.



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# File 'lib/rex/socket.rb', line 825

def localhost
  @localhost
end

#localport ⇒ Object

The local port of the connected socket.



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# File 'lib/rex/socket.rb', line 829

def localport
  @localport
end

#peerhost ⇒ Object

The peer host of the connected socket.



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# File 'lib/rex/socket.rb', line 813

def peerhost
  @peerhost
end

#peerhostname ⇒ Object

The peer hostname of the connected socket.



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# File 'lib/rex/socket.rb', line 817

def peerhostname
  @peerhostname
end

#peerport ⇒ Object

The peer port of the connected socket.



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# File 'lib/rex/socket.rb', line 821

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 314

def self.addr_atoc(mask)
  bits = is_ipv6?(mask) ? 128 : 32
  mask_i = resolv_nbo_i(mask)
  cidr = nil
  0.upto(bits) do |i|
    if ((1 << i)-1) << (bits - 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 348

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

.addr_atoi_list(addr) ⇒ Object

Converts a ascii address into a list of addresses



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# File 'lib/rex/socket.rb', line 355

def self.addr_atoi_list(addr)
  resolv_nbo_i_list(addr)
end

.addr_aton(addr) ⇒ Object

Converts a ascii address to network byte order



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# File 'lib/rex/socket.rb', line 373

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

.addr_ctoa(cidr, v6: false) ⇒ 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 331

def self.addr_ctoa(cidr, v6: false)
  bits = v6 ? 128 : 32
  cidr = cidr.to_i
  return nil unless (0..bits) === cidr
  addr_itoa(((1 << cidr)-1) << bits-cidr, v6)
end

.addr_itoa(addr, v6 = false) ⇒ Object

Converts an integer address into ascii



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# File 'lib/rex/socket.rb', line 364

def self.addr_itoa(addr, v6=false)
  nboa = addr_iton(addr, v6)

  addr_ntoa(nboa)
end

.addr_iton(addr, v6 = false) ⇒ Object

Converts an integer into a network byte order address

Parameters:

  • addr (Numeric) —

    The address as a number

  • v6 (Boolean) (defaults to: false) —

    Whether addr is IPv6



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# File 'lib/rex/socket.rb', line 445

def self.addr_iton(addr, v6=false)
  if(addr < 0x100000000 && !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) ⇒ String

Converts a network byte order address to ascii

Parameters:

  • addr (String) —

    Packed network-byte-order address

Returns:

  • (String) —

    Human readable IP address.

Raises:

  • (RuntimeError) 


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# File 'lib/rex/socket.rb', line 382

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

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

  raise RuntimeError, "Invalid address format"
end

.addr_ntoi(addr) ⇒ Object

Converts a network byte order address to an integer

Raises:

  • (RuntimeError) 


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# File 'lib/rex/socket.rb', line 423

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, ipv6 = false) ⇒ Object

Converts a bitmask (28) into a netmask (255.255.255.240)



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# File 'lib/rex/socket.rb', line 524

def self.bit2netmask(bitmask, ipv6=false)
  if bitmask > 32 or ipv6
    i = ((~((2 ** (128 - bitmask)) - 1)) & (2**128-1))
    n = Rex::Socket.addr_iton(i, true)
    return Rex::Socket.addr_ntoa(n)
  else
    [ (~((2 ** (32 - bitmask)) - 1)) & 0xffffffff ].pack('N').unpack('CCCC').join('.')
  end
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 475

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

.compress_address(addr) ⇒ String

Implement zero compression for IPv6 addresses. Uses the compression method from Marco Ceresa’s IPAddress GEM

Parameters:

  • addr (String) —

    Human readable IPv6 address

Returns:

  • (String) —

    Human readable IPv6 address with runs of 0s removed

See Also:



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# File 'lib/rex/socket.rb', line 404

def self.compress_address(addr)
  return addr unless is_ipv6?(addr)
  addr = addr.dup
  while true
    break if addr.sub!(/\A0:0:0:0:0:0:0:0\Z/, '::')
    break if addr.sub!(/\b0:0:0:0:0:0:0\b/, ':')
    break if addr.sub!(/\b0:0:0:0:0:0\b/, ':')
    break if addr.sub!(/\b0:0:0:0:0\b/, ':')
    break if addr.sub!(/\b0:0:0:0\b/, ':')
    break if addr.sub!(/\b0:0:0\b/, ':')
    break if addr.sub!(/\b0:0\b/, ':')
    break
  end
  addr.sub(/:{3,}/, '::')
end

.create(opts = {}) ⇒ Object

Create a socket instance using the supplied parameter hash.



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# File 'lib/rex/socket.rb', line 43

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 78

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 50

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 57

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 64

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 71

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 in “dotted” form

Returns:

  • (Boolean) 


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

def self.dotted_ip?(addr)
  (support_ipv6? && addr =~ MATCH_IPV6) || (addr =~ MATCH_IPV4)
end

.eth_aton(mac) ⇒ Object

Converts a colon-delimited MAC address into a 6-byte binary string



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# File 'lib/rex/socket.rb', line 461

def self.eth_aton(mac)
  mac.split(":").map{|c| c.to_i(16) }.pack("C*")
end

.eth_ntoa(bin) ⇒ Object

Converts a 6-byte binary string into a colon-delimited MAC address



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# File 'lib/rex/socket.rb', line 468

def self.eth_ntoa(bin)
  bin.unpack("C6").map{|x| "%.2x" % x }.join(":").upcase
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 270

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

.getaddress(hostname, accept_ipv6 = true) ⇒ String

Get the first address returned by a DNS lookup for hostname.

Parameters:

  • hostname (String) —

    A hostname or ASCII IP address

Returns:

  • (String) —

    ASCII IP address

See Also:



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# File 'lib/rex/socket.rb', line 200

def self.getaddress(hostname, accept_ipv6 = true)
  getaddresses(hostname, accept_ipv6).first
end

.getaddresses(hostname, accept_ipv6 = true) ⇒ Array<String>

Wrapper for ::Addrinfo.getaddrinfo that takes special care to see if the supplied address is already an ASCII IP address. This is necessary to prevent blocking while waiting on a DNS reverse lookup when we already have what we need.

Parameters:

  • hostname (String) —

    A hostname or ASCII IP address

Returns:

  • (Array<String>)

Raises:

  • (::SocketError) 


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# File 'lib/rex/socket.rb', line 212

def self.getaddresses(hostname, accept_ipv6 = true)
  raise ::SocketError, 'getaddrinfo: nodename nor servname provided, or not known' if hostname.nil?

  if hostname =~ MATCH_IPV4 || (accept_ipv6 && hostname =~ MATCH_IPV6)
    return [hostname]
  end

  res = ::Addrinfo.getaddrinfo(hostname, 0, ::Socket::AF_UNSPEC, ::Socket::SOCK_STREAM)

  res.map! do |address_info|
    address_info.ip_address
  end

  unless accept_ipv6
    res.reject! { |ascii| ascii =~ MATCH_IPV6 }
  end

  res
end

.gethostbyname(host) ⇒ Object

Deprecated.

Please use #getaddress, #resolv_nbo, or similar instead.

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 239

def self.gethostbyname(host)
  warn "NOTE: #{self}.#{__method__} is deprecated, use getaddress, resolv_nbo, or similar instead. It will be removed in the next Major version"
  if is_ipv4?(host)
    return [ host, [], 2, host.split('.').map{ |c| c.to_i }.pack("C4") ]
  end

  if is_ipv6?(host)
    # pop off the scopeid since gethostbyname isn't smart enough to
    # deal with it.
    host, _ = host.split('%', 2)
  end

  ::Socket.gethostbyname(host)
end

.ipv6_link_address(intf) ⇒ Object

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



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# File 'lib/rex/socket.rb', line 641

def self.ipv6_link_address(intf)
  r = source_address("FF02::1%#{intf}")
  return nil if r.nil? || 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 650

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 190

def self.is_internal?(addr)
  self.dotted_ip?(addr) && addr =~ MATCH_IPV4_PRIVATE
end

.is_ip_addr?(addr) ⇒ Boolean

Determine whether this is an IP address at all Check for v4 (less expensive), v6, else false

Returns:

  • (Boolean) 


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# File 'lib/rex/socket.rb', line 149

def self.is_ip_addr?(addr)
  self.is_ipv4?(addr) || self.is_ipv6?(addr)
end

.is_ipv4?(addr) ⇒ Boolean

Determine whether this is an IPv4 address

Returns:

  • (Boolean) 


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# File 'lib/rex/socket.rb', line 127

def self.is_ipv4?(addr)
  addr =~ MATCH_IPV4 ? true : false
end

.is_ipv6?(addr) ⇒ Boolean

Determine whether this is an IPv6 address

Returns:

  • (Boolean) 


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# File 'lib/rex/socket.rb', line 134

def self.is_ipv6?(addr)
  addr =~ MATCH_IPV6 ? true : false
end

.is_mac_addr?(addr) ⇒ Boolean

Determine whether this is a MAC address

Returns:

  • (Boolean) 


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# File 'lib/rex/socket.rb', line 141

def self.is_mac_addr?(addr)
  !(addr =~ MATCH_MAC_ADDR).nil?
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 504

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 580

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 535

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

.portspec_to_portlist(pspec) ⇒ Object

Converts a port specification like “80,21-25,!24,443” into a sorted, unique array of valid port numbers like [21,22,23,25,80,443]



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# File 'lib/rex/socket.rb', line 543

def self.portspec_to_portlist(pspec)
  ports = []
  remove = []

  # Build ports array from port specification
  pspec.split(/,/).each do |item|
    target = ports

    item.strip!

    if item.start_with? '!'
      item.delete! '!'
      target = remove
    end

    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| target << p }
  end

  if ports.empty? and not remove.empty? then
    ports = 1.upto 65535
  end

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

.resolv_nbo(host, accepts_ipv6 = true) ⇒ Object

Resolves a host to raw network-byte order.



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# File 'lib/rex/socket.rb', line 282

def self.resolv_nbo(host, accepts_ipv6 = true)
  ip_address = Rex::Socket.getaddress(host, accepts_ipv6)
  IPAddr.new(ip_address).hton
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 299

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

.resolv_nbo_i_list(host) ⇒ Object

Resolves a host to a list of network-byte order ruby integers.



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# File 'lib/rex/socket.rb', line 306

def self.resolv_nbo_i_list(host)
  resolv_nbo_list(host).map{|addr| addr_ntoi(addr) }
end

.resolv_nbo_list(host) ⇒ Object

Resolves a host to raw network-byte order.



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# File 'lib/rex/socket.rb', line 290

def self.resolv_nbo_list(host)
  Rex::Socket.getaddresses(host).map do |addresses|
    IPAddr.new(addresses).hton
  end
end

.resolv_to_dotted(host) ⇒ Object

Resolves a host to a dotted address.



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

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 620

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]

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

.support_ipv6? ⇒ Boolean

Determine whether we support IPv6

Returns:

  • (Boolean) 


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# File 'lib/rex/socket.rb', line 107

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_pair ⇒ Object

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 666

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, _ = server.accept
    server.close
  }

  threads.each { |t| t.join }

  return [lsock, rsock]
end

.to_authority(host, port = nil) ⇒ String

Checks to see if an address is an IPv6 address and if so, converts it into its square bracket format for addressing as noted in RFC 6874 which states that an IPv6 address literal in a URL is always embedded between [ and ]. Please also refer to RFC5952, RFC3986, and RFC6874 for more info.

RFC3986 section 3.2.2 specifically notes “A host identified by an Internet Protocol literal address, version 6

RFC3513

or later, is distinguished by enclosing the IP literal

within square brackets (“[” and “]”). This is the only place where square bracket characters are allowed in the URI syntax.“

RFC6874 reinforces this in section 2 where it notes “In a URI, a literal IPv6 address is always embedded between ‘[’ and ‘]’”.

Parameters:

  • host (String) —

    IP address or hostname to convert to a URI authority.

  • port (Integer) (defaults to: nil) —

    Port number to include within the URI authority.

Returns:

  • (String) —

    Returns the URI authority string.

Raises:

  • (ArgumentError) —

    This function will raise an ArgumentError if the host parameter is not a String.



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# File 'lib/rex/socket.rb', line 177

def self.to_authority(host, port=nil)
  unless host.kind_of?(String)
    raise ArgumentError.new("Expected a string for the host parameter!")
  end
  host = "[#{host}]" if is_ipv6?(host)
  host += ":#{port}" if port
  host
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 258

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_pair ⇒ Object

Create a UDP socket pair using native ruby UDP sockets.



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# File 'lib/rex/socket.rb', line 706

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

#fd ⇒ Object

By default, all sockets are themselves selectable file descriptors.



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# File 'lib/rex/socket.rb', line 747

def fd
  self
end

#getlocalname ⇒ Object

Wrapper around getsockname that stores the local address and local port values.



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# File 'lib/rex/socket.rb', line 761

def getlocalname
  if [nil, '0.0.0.0', '::'].include?(self.localhost) && [nil, 0].include?(self.localport)
    _, self.localhost, self.localport = getsockname
  end

  family = Socket.is_ipv4?(self.localhost) ? ::Socket::AF_INET : ::Socket::AF_INET6
  [family, self.localhost, self.localport]
end

#getpeername_as_array ⇒ Object

Returns peer connection information as an array.



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# File 'lib/rex/socket.rb', line 773

def getpeername_as_array
  peer_name = nil
  begin
    peer_name = Socket.from_sockaddr(self.getpeername)
  rescue ::Errno::EINVAL => e
    # Ruby's getpeername method may call rb_sys_fail("getpeername(2)")
    elog("#{e.message} (#{e.class})#{e.backtrace * "\n"}\n", LogSource, LEV_3)
  end

  return peer_name
end

#getsockname ⇒ Object

Returns local connection information.



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# File 'lib/rex/socket.rb', line 754

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 732

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

#localinfo ⇒ Object

Returns local information (host + port) in host:port format.



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# File 'lib/rex/socket.rb', line 797

def localinfo
  if (pi = getlocalname)
    return pi[1] + ':' + pi[2].to_s
  end
end

#peerinfo ⇒ Object

Returns peer information (host + port) in host:port format.



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# File 'lib/rex/socket.rb', line 788

def peerinfo
  if (pi = getpeername_as_array)
    return pi[1] + ':' + pi[2].to_s
  end
end

#type? ⇒ Boolean

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

Returns:

  • (Boolean)

Raises:

  • (NotImplementedError) 


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# File 'lib/rex/socket.rb', line 806

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