Source: ../../bgp/packet.hh
|
|
|
|
// -*- c-basic-offset: 4; tab-width: 8; indent-tabs-mode: t -*-
// Copyright (c) 2001-2004 International Computer Science Institute
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software")
// to deal in the Software without restriction, subject to the conditions
// listed in the XORP LICENSE file. These conditions include: you must
// preserve this copyright notice, and you cannot mention the copyright
// holders in advertising related to the Software without their permission.
// The Software is provided WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED. This
// notice is a summary of the XORP LICENSE file; the license in that file is
// legally binding.
// $XORP: xorp/bgp/packet.hh,v 1.28 2004/06/10 22:40:31 hodson Exp $
#ifndef __BGP_PACKET_HH__
#define __BGP_PACKET_HH__
#include "config.h"
#include <iostream>
#include <string.h>
#include <stdio.h>
#include <inttypes.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/uio.h>
#include <netinet/in.h>
#include <unistd.h>
#include "exceptions.hh"
#include "parameter.hh"
#include "local_data.hh"
#include "peer_data.hh"
#include "path_attribute.hh"
#include "update_attrib.hh"
#include "libxorp/ipv4net.hh"
#include "libxorp/ipv4.hh"
#include "libxorp/debug.h"
enum BgpPacketType {
MESSAGETYPEOPEN = 1,
MESSAGETYPEUPDATE = 2,
MESSAGETYPENOTIFICATION = 3,
MESSAGETYPEKEEPALIVE = 4
};
/**
* Notification message error codes with associated subcodes.
*/
enum Notify {
#define UNSPECIFIED 0 // Unspecified subcode error
MSGHEADERERR = 1, // Message Header Error
#define CONNNOTSYNC 1 // Connection Not Synchronized
#define BADMESSLEN 2 // Bad Message Length
#define BADMESSTYPE 3 // Bad Message Type
OPENMSGERROR = 2, // OPEN Message Error
#define UNSUPVERNUM 1 // Unsupported Version Number
#define BADASPEER 2 // Bad Peer AS
#define BADBGPIDENT 3 // Bad BGP Identifier
#define UNSUPOPTPAR 4 // Unsupported Optional Parameter
#define AUTHFAIL 5 // Authentication Failure
#define UNACCEPTHOLDTIME 6 // Unacceptable Hold Time
#define UNSUPCAPABILITY 7 // Unsupported Capability (RFC 3392)
UPDATEMSGERR = 3, // UPDATE Message Error
#define MALATTRLIST 1 // Malformed Attribute List
#define UNRECOGWATTR 2 // Unrecognized Well-known Attribute
#define MISSWATTR 3 // Missing Well-known Attribute
#define ATTRFLAGS 4 // Attribute Flags Error
#define ATTRLEN 5 // Attribute Length Error
#define INVALORGATTR 6 // Invalid ORIGIN Attribute
//#define
#define INVALNHATTR 8 // Invalid NEXT_HOP Attribute
#define OPTATTR 9 // Optional Attribute Error
#define INVALNETFIELD 10 // Invalid Network Field
#define MALASPATH 11 // Malformed AS_PATH
HOLDTIMEEXP = 4, // Hold Timer Expired
FSMERROR = 5, // Finite State Machine Error
CEASE = 6 // Cease
};
#define MARKER_SIZE 16
/**
* Overlay for the BGP common header (on the wire)
*/
struct fixed_header {
uint8_t marker[MARKER_SIZE]; // normally all bits are ones.
uint16_t length; // this is in network format
uint8_t type; // enum BgpPacketType
};
// size of fixed_header
const size_t BGP_COMMON_HEADER_LEN = 19;
/*
* Various min and max packet size, accounting for the basic
* information in the packet itself
*/
const size_t MINPACKETSIZE = BGP_COMMON_HEADER_LEN;
const size_t MAXPACKETSIZE = 4096;
const size_t MINOPENPACKET = BGP_COMMON_HEADER_LEN + 10;
const size_t MINUPDATEPACKET = BGP_COMMON_HEADER_LEN + 2 + 2;
const size_t MINKEEPALIVEPACKET = BGP_COMMON_HEADER_LEN;
const size_t MINNOTIFICATIONPACKET = BGP_COMMON_HEADER_LEN + 2;
/**
* The main container for BGP messages (packets) which are sent
* back and forth.
*
* This base class only contains the standard fields (length, type)
* leaving other information to be stored in the derived objects.
*/
class BGPPacket {
public:
/**
* Status returned by message reader.
*/
enum Status {
GOOD_MESSAGE,
ILLEGAL_MESSAGE_LENGTH,
CONNECTION_CLOSED,
};
// The default marker.
static const uint8_t Marker[MARKER_SIZE];
BGPPacket() {}
virtual ~BGPPacket() {}
uint8_t type() const { return _Type; }
virtual string str() const = 0;
virtual const uint8_t *encode(size_t &len, uint8_t *buf = 0) const = 0;
protected:
/*
* Return the external representation of the packet into a buffer.
* If the caller supplies the buffer it is its responsibility to make
* sure that it has the correct size, otherwise the routine will
* allocate it with new uint8_t[len].
* It is responsibility of the caller to dispose of the buffer.
* Note that this routine will only copy the fixed_header part.
* The derived-class methods are in charge of filling up any
* additional data past it.
*/
uint8_t *basic_encode(size_t len, uint8_t *buf) const;
// don't allow the use of the default copy constructor
BGPPacket(const BGPPacket& BGPPacket);
uint8_t _Type;
private:
};
/* **************** OpenPacket *********************** */
class OpenPacket : public BGPPacket {
public:
OpenPacket(const uint8_t *d, uint16_t l)
throw(CorruptMessage);
OpenPacket(const AsNum& as, const IPv4& bgpid, const uint16_t holdtime);
~OpenPacket() {}
const uint8_t *encode(size_t& len, uint8_t *buf = 0) const;
string str() const;
const uint8_t Version() const { return _Version; }
const AsNum as() const { return _as; }
const uint16_t HoldTime() const { return _HoldTime; }
const IPv4 id() const { return _id; }
const uint8_t OptParmLen() const { return _OptParmLen; }
bool operator==(const OpenPacket& him) const;
void add_parameter(const ParameterNode& p);
const ParameterList& parameter_list() const { return _parameter_list; }
protected:
private:
OpenPacket();
// don't allow the use of the default copy constructor
OpenPacket(const OpenPacket& OpenPacket);
IPv4 _id;
AsNum _as;
uint16_t _HoldTime;
uint8_t _OptParmLen;
uint8_t _Version;
ParameterList _parameter_list;
};
/* **************** UpdatePacket *********************** */
class UpdatePacket : public BGPPacket {
public:
UpdatePacket();
UpdatePacket(const uint8_t *d, uint16_t l)
throw(CorruptMessage);
~UpdatePacket();
void add_withdrawn(const BGPUpdateAttrib& wdr);
void add_pathatt(const PathAttribute& pa);
void add_pathatt(PathAttribute *pa);
void add_nlri(const BGPUpdateAttrib& nlri);
const BGPUpdateAttribList& wr_list() const { return _wr_list; }
const PathAttributeList<IPv4>& pa_list() const { return _pa_list; }
const BGPUpdateAttribList& nlri_list() const { return _nlri_list; }
template <typename A> MPReachNLRIAttribute<A> *mpreach(Safi) const;
template <typename A> MPUNReachNLRIAttribute<A> *mpunreach(Safi) const;
const uint8_t *encode(size_t& len, uint8_t *buf = 0) const;
bool big_enough() const;
string str() const;
bool operator==(const UpdatePacket& him) const;
protected:
private:
// don't allow the use of the default copy constructor
UpdatePacket(const UpdatePacket& UpdatePacket);
BGPUpdateAttribList _wr_list;
PathAttributeList<IPv4> _pa_list;
BGPUpdateAttribList _nlri_list;
};
template <typename A>
MPReachNLRIAttribute<A> *
UpdatePacket::mpreach(Safi safi) const
{
XLOG_ASSERT(!(A::ip_version() == 4 && SAFI_UNICAST == safi));
typename PathAttributeList<A>::const_iterator i;
for( i = _pa_list.begin(); i != _pa_list.end(); i++) {
MPReachNLRIAttribute<A> *mpreach =
dynamic_cast<MPReachNLRIAttribute<A> *>((*i));
if (mpreach && mpreach->safi() == safi) {
return mpreach;
}
}
return 0;
}
template <typename A>
MPUNReachNLRIAttribute<A> *
UpdatePacket::mpunreach(Safi safi) const
{
XLOG_ASSERT(!(A::ip_version() == 4 && SAFI_UNICAST == safi));
typename PathAttributeList<A>::const_iterator i;
for( i = _pa_list.begin(); i != _pa_list.end(); i++) {
MPUNReachNLRIAttribute<A> *mpunreach =
dynamic_cast<MPUNReachNLRIAttribute<A> *>((*i));
if (mpunreach && mpunreach->safi() == safi) {
return mpunreach;
}
}
return 0;
}
/* **************** BGPNotificationPacket *********************** */
class NotificationPacket : public BGPPacket {
public:
NotificationPacket(const uint8_t *d, uint16_t l) throw(InvalidPacket);
NotificationPacket(uint8_t ec, uint8_t esc = 0,
const uint8_t *d = 0, size_t l=0);
NotificationPacket();
~NotificationPacket() { delete[] _error_data; }
uint8_t error_code() const { return _error_code; }
uint8_t error_subcode() const { return _error_subcode; }
/**
* Verify that the supplied error code and subcode are legal.
*/
static bool validate_error_code(const int error, const int subcode);
/**
* Generate a human readable error string.
*/
static string pretty_print_error_code(const int error, const int subcode,
const uint8_t* error_data = 0);
const uint8_t* error_data() const { return _error_data; }
const uint8_t *encode(size_t &len, uint8_t *buf = 0) const;
string str() const;
bool operator==(const NotificationPacket& him) const;
protected:
private:
// don't allow the use of the default copy constructor
NotificationPacket(const NotificationPacket& Notificationpacket);
size_t _Length; // total size incl. header
const uint8_t* _error_data;
uint8_t _error_code;
uint8_t _error_subcode;
};
/**
* KeepAlivePacket are extremely simple, being made only of a header.
* with the appropriate type and length.
*/
class KeepAlivePacket : public BGPPacket {
public:
/**
* need nothing to parse incoming data
*/
KeepAlivePacket(const uint8_t *, uint16_t l)
throw(CorruptMessage) {
if (l != MINKEEPALIVEPACKET)
xorp_throw(CorruptMessage,
c_format("KeepAlivePacket length %d instead of %u",
l, (uint32_t)MINKEEPALIVEPACKET),
MSGHEADERERR, UNSPECIFIED);
_Type = MESSAGETYPEKEEPALIVE;
}
KeepAlivePacket() {
_Type = MESSAGETYPEKEEPALIVE;
}
~KeepAlivePacket() {}
const uint8_t *encode(size_t &len, uint8_t *buf = 0) const {
len = MINKEEPALIVEPACKET;
return basic_encode(len, buf);
}
virtual string str() const { return "Keepalive Packet\n"; }
bool operator==(const KeepAlivePacket&) const { return true; }
protected:
private:
// don't allow the use of the default copy constructor
KeepAlivePacket(const KeepAlivePacket& KeepAlivePacket);
};
#endif // __BGP_PACKET_HH__
Generated by: pavlin on possum.icir.org on Thu Jul 8 23:48:33 2004, using kdoc $.
