FBB::Cidr(3bobcat)						   CIDR matching						FBB::Cidr(3bobcat)

NAME

       FBB::Cidr - Compares IP4 addresses to CIDR specifications

SYNOPSIS

       #include <bobcat/errno>
       Linking option: -lbobcat

DESCRIPTION

       Objects of the class Cidr can be used for testing whether IP4 Internet addresses belong to address ranges defined by Classless Inter-Domain
       Routing (CIDR) address block specifications. CIDR blocks are specified as a.b.c.d/m where a.b.c.d are the four octets of a  dotted  decimal
       IP4 address specification (e.g., 129.125.14.80) and m is a mask-size (ranging from 0 to 32) defining the number of most significant bits to
       remain  as-is.  The  CIDR  specification  129.125.14.80/16  defines  a  class  B  network,  with  addresses  ranging  from  129.125.0.0	to
       129.125.255.255.

       The  mask  size	does  not  have to be a multiple of 8. E.g., when specifying 129.125.14.80/5 only the most significant 5 bits of the first
       octed are fixed, resulting in an address range ranging from 128.0.0.0 to 135.255.255.255.

       CIDR specifications passed to a Cidr object must be of the form a.b.c.d or a.b.c.d/m. If the mask is not specified a  mask-size	of  32	is
       used,  effectively  defining  an  address  range  of  only one address. Mask values of 0 are ignored.  Mask values of 0 are ignored by Cidr
       objects.

       When specifying CIDRs on a stream, empty lines and comment lines (having a hash-character (#)  as  their  first	non-blank  character)  are
       ignored.   Non-empty  lines must start with a CIDR specification, and the Cidr object will ignore all information on a line trailing a CIDR
       specification.

NAMESPACE

       FBB
       All constructors, members, operators and manipulators, mentioned in this man-page, are defined in the namespace FBB.

INHERITS FROM

       -

CONSTRUCTORS

       o      Cidr(std::string const &cidrPattern):
	      The Cidr object is initialized with a single CIDR specification.

       o      Cidr(std::istream &cidrStream):
	      The Cidr object is initialized with CIDR specifications read from the std::istream cidrStream.  The default, copy and move construc-
	      tors are available.

OVERLOADED OPERATORS

       The copy and move assignment operators are available.

MEMBER FUNCTIONS

       The return valuess of the accessors (i.e., the const members) are only defined following a successful match (see below, the match members).

       o      std::string const &address() const:
	      returns the address matching a CIDR.

       o      std::string cidr() const:
	      returns the CIDR containing a specified address.

       o      std::string first() const:
	      returns the first address of the range of addresses defined by the CIDR specification.

       o      std::string last() const:
	      returns  the last address of the range of addresses defined by the CIDR specification. Note that first, last do not define an itera-
	      tor range. The address returned by last still belongs to the CIDR-range.

       o      bool match(std::istream &in):
	      The value true is returned when an IP4 address found in the lines of in belongs to a CIDR range inspected by the	Cidr  object.  The
	      match function returns true at the first matching address.  E.g., if a line contains the text

		  This is address 1.2.3.4 and this is 5.6.7.8

	      and the CIDR specifications

		      5.1.1.1/8
		      1.2.1.1/16

	      were provided to the Cidr object, then the object will report a match for 5.6.7.8.

	      As  soon	as a match is found match returns true. If none of the addresses found in the lines of in matches any of the object's CIDR
	      specifications, false is returned.

       o      std::string mask() const:
	      returns the mask used by the CIDR specification.

       o      bool match(std::string const &line):
	      The value true is returned when an IP4 address found in line belongs to a CIDR range inspected by the Cidr object. The  match  func-
	      tion returns true at the first matching address.

	      If none of the addresses found in line matches any of the object's CIDR specifications, false is returned.

       o      void setCidr(std::istream &cidrStream):
	      A new set of CIDR specification is loaded into the Cidr object, reading the specifications from cidrStream.

       o      void setCidr(std::string const &cidrPattern):
	      A  new CIDR specification is loaded into the Cidr object, using the specification found in cidrPattern.  The Cidr object is initial-
	      ized with a single CIDR specification which must be of the form a.b.c.d or a.b.c.d/m. If the mask is not specified a mask-size of 32
	      is used, effectively defining an address range of only one address. Mask values of 0 are ignored.

STATIC MEMBERS

       o      size_t dotted2binary(std::string const &dotted):
	      Converts "a.b.c.d" to a 32-bits value

       o      std::string binary2dotted(size_t binary):
	      Converts a 32-bits value to a dotted decimal IP4 address

EXAMPLE

       #include <fstream>
       #include <iostream>

       #include <bobcat/errno>
       #ifdef BOBCAT
	   #include <bobcat/cidr>
       #else
	   #include "cidr"
       #endif

       using namespace std;
       using namespace FBB;

       int main(int argc, char **argv)
       {
	   enum Spec
	   {
	       NONE,
	       FILE,
	       CIN
	   };

	   Spec spec = CIN;
	   ifstream in;

	   if (argc > 1)
	   {
	       Errno::open(in, argv[1]);       // file containing cidr-specs
	       spec = FILE;
	   }

	   while (true)
	   {
	       string cidrSpec;
	       if (spec == CIN)
	       {
		   cout << "Specify cidr (empty to quit): ";
		   if (!getline(cin, cidrSpec) || cidrSpec.empty())
		       break;
	       }
	       try
	       {
		   Cidr cidr;

		   switch (spec)
		   {
		       case NONE:
		       return 0;

		       case FILE:
			   cidr.setCidr(in);
			   spec = NONE;
		       break;

		       case CIN:
			   cidr.setCidr(cidrSpec);
		   }

		   while (true)
		   {
		       cout << "Specify address to test (empty to " <<
			   (spec == CIN ? "respec. CIDR" : "quit") << "): ";
		       string address;
		       if (!getline(cin, address) || address.empty())
			   break;

		       if (!cidr.match(address))
		       {
			   cout << "Address " << address << " not in ";
			   if (spec == CIN)
			       cout << cidrSpec << '
';
			   else
			       cout << "specifications in " << argv[1] << '
';
		       }
		       else
			   cout << "Address " << address << " in " << cidr.cidr() <<
									       "
"
			       "Lowest address: " << cidr.first() << "
"
			       "Highest address: " << cidr.last() << "
"
			       "CIDR mask: " << cidr.mask() << "
"
			       "Address: " << cidr.address() << '
';
		   }
	       }
	       catch (Errno const &err)
	       {
		   cout << "Oops... " << err.why() << "
"
			   "Try again...
";
	       }
	   }
       }

FILES

       bobcat/cidr - defines the class interface

SEE ALSO

       bobcat(7)

BUGS

       Members of Cidr use static data. The current implementation of Cidr is therefore not thread-safe.

DISTRIBUTION FILES

       o      bobcat_3.01.00-x.dsc: detached signature;

       o      bobcat_3.01.00-x.tar.gz: source archive;

       o      bobcat_3.01.00-x_i386.changes: change log;

       o      libbobcat1_3.01.00-x_*.deb: debian package holding the libraries;

       o      libbobcat1-dev_3.01.00-x_*.deb: debian package holding the libraries, headers and manual pages;

       o      http://sourceforge.net/projects/bobcat: public archive location;

BOBCAT

       Bobcat is an acronym of `Brokken's Own Base Classes And Templates'.

COPYRIGHT

       This is free software, distributed under the terms of the GNU General Public License (GPL).

AUTHOR

       Frank B. Brokken (f.b.brokken@rug.nl).

libbobcat1-dev_3.01.00-x.tar.gz 				     2005-2012							FBB::Cidr(3bobcat)