packet.h

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/* -*-  Mode:C++; c-basic-offset:8; tab-width:8; indent-tabs-mode:t -*- */
/*
 * Copyright (c) 1997 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the Computer Systems
 *      Engineering Group at Lawrence Berkeley Laboratory.
 * 4. Neither the name of the University nor of the Laboratory may be used
 *    to endorse or promote products derived from this software without
 *    specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * @(#) $Header: /nfs/jade/vint/CVSROOT/ns-2/common/packet.h,v 1.93 2003/02/02 22:33:53 xuanc Exp $ (LBL)
 */

#ifndef ns_packet_h
#define ns_packet_h

#include <string.h>
#include <assert.h>

#include "config.h"
#include "scheduler.h"
#include "object.h"
#include "lib/bsd-list.h"
#include "packet-stamp.h"
#include "ns-process.h"

// Used by wireless routing code to attach routing agent
#define RT_PORT         255     /* port that all route msgs are sent to */

#define HDR_CMN(p)      (hdr_cmn::access(p))
#define HDR_ARP(p)      (hdr_arp::access(p))
#define HDR_MAC(p)      (hdr_mac::access(p))
#define HDR_MAC802_11(p) ((hdr_mac802_11 *)hdr_mac::access(p))
#define HDR_MAC_TDMA(p) ((hdr_mac_tdma *)hdr_mac::access(p))
#define HDR_SMAC(p)     ((hdr_smac *)hdr_mac::access(p))
#define HDR_LL(p)       (hdr_ll::access(p))
#define HDR_IP(p)       (hdr_ip::access(p))
#define HDR_RTP(p)      (hdr_rtp::access(p))
#define HDR_TCP(p)      (hdr_tcp::access(p))
#define HDR_SR(p)       (hdr_sr::access(p))
#define HDR_TFRC(p)     (hdr_tfrc::access(p))
#define HDR_TORA(p)     (hdr_tora::access(p))
#define HDR_IMEP(p)     (hdr_imep::access(p))
#define HDR_CDIFF(p)    (hdr_cdiff::access(p))  /* chalermak's diffusion*/
//#define HDR_DIFF(p)     (hdr_diff::access(p))  /* SCADD's diffusion ported into ns */
#define HDR_LMS(p)              (hdr_lms::access(p))

/* --------------------------------------------------------------------*/

enum packet_t {
        PT_TCP,
        PT_UDP,
        PT_CBR,
        PT_AUDIO,
        PT_VIDEO,
        PT_ACK,
        PT_START,
        PT_STOP,
        PT_PRUNE,
        PT_GRAFT,
        PT_GRAFTACK,
        PT_JOIN,
        PT_ASSERT,
        PT_MESSAGE,
        PT_RTCP,
        PT_RTP,
        PT_RTPROTO_DV,
        PT_CtrMcast_Encap,
        PT_CtrMcast_Decap,
        PT_SRM,
        /* simple signalling messages */
        PT_REQUEST,     
        PT_ACCEPT,      
        PT_CONFIRM,     
        PT_TEARDOWN,    
        PT_LIVE,        // packet from live network
        PT_REJECT,

        PT_TELNET,      // not needed: telnet use TCP
        PT_FTP,
        PT_PARETO,
        PT_EXP,
        PT_INVAL,
        PT_HTTP,

        /* new encapsulator */
        PT_ENCAPSULATED,
        PT_MFTP,

        /* CMU/Monarch's extnsions */
        PT_ARP,
        PT_MAC,
        PT_TORA,
        PT_DSR,
        PT_AODV,
        PT_IMEP,

        // RAP packets
        PT_RAP_DATA,
        PT_RAP_ACK,

        PT_TFRC,
        PT_TFRC_ACK,
        PT_PING,

        // Diffusion packets - Chalermek
        PT_DIFF,

        // LinkState routing update packets
        PT_RTPROTO_LS,

        // MPLS LDP header
        PT_LDP,

        // GAF packet
        PT_GAF,  

        // ReadAudio traffic
        PT_REALAUDIO,

        // Pushback Messages
        PT_PUSHBACK,

#ifdef HAVE_STL
        // Pragmatic General Multicast
        PT_PGM,
#endif //STL

        // LMS packets
        PT_LMS,
        PT_LMS_SETUP,

        // insert new packet types here
        PT_NTYPE // This MUST be the LAST one
};

class p_info {
public:
        p_info() {
                name_[PT_TCP]= "tcp";
                name_[PT_UDP]= "udp";
                name_[PT_CBR]= "cbr";
                name_[PT_AUDIO]= "audio";
                name_[PT_VIDEO]= "video";
                name_[PT_ACK]= "ack";
                name_[PT_START]= "start";
                name_[PT_STOP]= "stop";
                name_[PT_PRUNE]= "prune";
                name_[PT_GRAFT]= "graft";
                name_[PT_GRAFTACK]= "graftAck";
                name_[PT_JOIN]= "join";
                name_[PT_ASSERT]= "assert";
                name_[PT_MESSAGE]= "message";
                name_[PT_RTCP]= "rtcp";
                name_[PT_RTP]= "rtp";
                name_[PT_RTPROTO_DV]= "rtProtoDV";
                name_[PT_CtrMcast_Encap]= "CtrMcast_Encap";
                name_[PT_CtrMcast_Decap]= "CtrMcast_Decap";
                name_[PT_SRM]= "SRM";

                name_[PT_REQUEST]= "sa_req";    
                name_[PT_ACCEPT]= "sa_accept";
                name_[PT_CONFIRM]= "sa_conf";
                name_[PT_TEARDOWN]= "sa_teardown";
                name_[PT_LIVE]= "live"; 
                name_[PT_REJECT]= "sa_reject";

                name_[PT_TELNET]= "telnet";
                name_[PT_FTP]= "ftp";
                name_[PT_PARETO]= "pareto";
                name_[PT_EXP]= "exp";
                name_[PT_INVAL]= "httpInval";
                name_[PT_HTTP]= "http";
                name_[PT_ENCAPSULATED]= "encap";
                name_[PT_MFTP]= "mftp";
                name_[PT_ARP]= "ARP";
                name_[PT_MAC]= "MAC";
                name_[PT_TORA]= "TORA";
                name_[PT_DSR]= "DSR";
                name_[PT_AODV]= "AODV";
                name_[PT_IMEP]= "IMEP";

                name_[PT_RAP_DATA] = "rap_data";
                name_[PT_RAP_ACK] = "rap_ack";

                name_[PT_TFRC]= "tcpFriend";
                name_[PT_TFRC_ACK]= "tcpFriendCtl";
                name_[PT_PING]="ping";

                /* For diffusion : Chalermek */
                name_[PT_DIFF] = "diffusion";

                // Link state routing updates
                name_[PT_RTPROTO_LS] = "rtProtoLS";

                // MPLS LDP packets
                name_[PT_LDP] = "LDP";

                // for GAF
                name_[PT_GAF] = "gaf";      

                // RealAudio packets
                name_[PT_REALAUDIO] = "ra";

                //pushback 
                name_[PT_PUSHBACK] = "pushback";

#ifdef HAVE_STL
                // for PGM
                name_[PT_PGM] = "PGM";
#endif //STL

                // LMS entries
                name_[PT_LMS]="LMS";
                name_[PT_LMS_SETUP]="LMS_SETUP";

                name_[PT_NTYPE]= "undefined";
        }
        const char* name(packet_t p) const { 
                if ( p <= PT_NTYPE ) return name_[p];
                return 0;
        }
        static bool data_packet(packet_t type) {
                return ( (type) == PT_TCP || \
                         (type) == PT_TELNET || \
                         (type) == PT_CBR || \
                         (type) == PT_AUDIO || \
                         (type) == PT_VIDEO || \
                         (type) == PT_ACK \
                         );
        }
private:
        static char* name_[PT_NTYPE+1];
};
extern p_info packet_info; /* map PT_* to string name */
//extern char* p_info::name_[];


#define DATA_PACKET(type) ( (type) == PT_TCP || \
                            (type) == PT_TELNET || \
                            (type) == PT_CBR || \
                            (type) == PT_AUDIO || \
                            (type) == PT_VIDEO || \
                            (type) == PT_ACK \
                            )


#define OFFSET(type, field)     ((int) &((type *)0)->field)

class PacketData : public AppData {
public:
        PacketData(int sz) : AppData(PACKET_DATA) {
                datalen_ = sz;
                if (datalen_ > 0)
                        data_ = new unsigned char[datalen_];
                else
                        data_ = NULL;
        }
        PacketData(PacketData& d) : AppData(d) {
                datalen_ = d.datalen_;
                if (datalen_ > 0) {
                        data_ = new unsigned char[datalen_];
                        memcpy(data_, d.data_, datalen_);
                } else
                        data_ = NULL;
        }
        virtual ~PacketData() { 
                if (data_ != NULL) 
                        delete []data_; 
        }
        unsigned char* data() { return data_; }

        virtual int size() const { return datalen_; }
        virtual AppData* copy() { return new PacketData(*this); }
private:
        unsigned char* data_;
        int datalen_;
};

//Monarch ext
typedef void (*FailureCallback)(Packet *,void *);

class Packet : public Event {
private:
        unsigned char* bits_;   // header bits
//      unsigned char* data_;   // variable size buffer for 'data'
//      unsigned int datalen_;  // length of variable size buffer
        AppData* data_;         // variable size buffer for 'data'
        static void init(Packet*);     // initialize pkt hdr 
        bool fflag_;
protected:
        static Packet* free_;   // packet free list
        int     ref_count_;     // free the pkt until count to 0
public:
        Packet* next_;          // for queues and the free list
        static int hdrlen_;

        Packet() : bits_(0), data_(0), ref_count_(0), next_(0) { }
        inline unsigned char* const bits() { return (bits_); }
        inline Packet* copy() const;
        inline Packet* refcopy() { ++ref_count_; return this; }
        inline int& ref_count() { return (ref_count_); }
        static inline Packet* alloc();
        static inline Packet* alloc(int);
        inline void allocdata(int);
        // dirty hack for diffusion data
        inline void initdata() { data_  = 0;}
        static inline void free(Packet*);
        inline unsigned char* access(int off) const {
                if (off < 0)
                        abort();
                return (&bits_[off]);
        }
        // This is used for backward compatibility, i.e., assuming user data
        // is PacketData and return its pointer.
        inline unsigned char* accessdata() const { 
                if (data_ == 0)
                        return 0;
                assert(data_->type() == PACKET_DATA);
                return (((PacketData*)data_)->data()); 
        }
        // This is used to access application-specific data, not limited 
        // to PacketData.
        inline AppData* userdata() const {
                return data_;
        }
        inline void setdata(AppData* d) { 
                if (data_ != NULL)
                        delete data_;
                data_ = d; 
        }
        inline int datalen() const { return data_ ? data_->size() : 0; }

        // Monarch extn

        static void dump_header(Packet *p, int offset, int length);

        // the pkt stamp carries all info about how/where the pkt
        // was sent needed for a receiver to determine if it correctly
        // receives the pkt
        PacketStamp     txinfo_;  

        /*
         * According to cmu code:
         * This flag is set by the MAC layer on an incoming packet
         * and is cleared by the link layer.  It is an ugly hack, but
         * there's really no other way because NS always calls
         * the recv() function of an object.
         * 
         */
        u_int8_t        incoming;

        //monarch extns end;
};

/* 
 * static constant associations between interface special (negative) 
 * values and their c-string representations that are used from tcl
 */
class iface_literal {
public:
        enum iface_constant { 
                UNKN_IFACE= -1, /* 
                                 * iface value for locally originated packets 
                                 */
                ANY_IFACE= -2   /* 
                                 * hashnode with iif == ANY_IFACE_   
                                 * matches any pkt iface (imported from TCL);
                                 * this value should be different from 
                                 * hdr_cmn::UNKN_IFACE (packet.h)
                                 */ 
        };
        iface_literal(const iface_constant i, const char * const n) : 
                value_(i), name_(n) {}
        inline int value() const { return value_; }
        inline const char * const name() const { return name_; }
private:
        const iface_constant value_;
        /* strings used in TCL to access those special values */
        const char * const name_; 
};

static const iface_literal UNKN_IFACE(iface_literal::UNKN_IFACE, "?");
static const iface_literal ANY_IFACE(iface_literal::ANY_IFACE, "*");

/*
 * Note that NS_AF_* doesn't necessarily correspond with
 * the constants used in your system (because many
 * systems don't have NONE or ILINK).
 */
enum ns_af_enum { NS_AF_NONE, NS_AF_ILINK, NS_AF_INET };

struct hdr_cmn {
        enum dir_t { DOWN= -1, NONE= 0, UP= 1 };
        packet_t ptype_;        // packet type (see above)
        int     size_;          // simulated packet size
        int     uid_;           // unique id
        int     error_;         // error flag
        int     errbitcnt_;     // # of corrupted bits jahn
        int     fecsize_;
        double  ts_;            // timestamp: for q-delay measurement
        int     iface_;         // receiving interface (label)
        dir_t   direction_;     // direction: 0=none, 1=up, -1=down
        // source routing 
        char src_rt_valid;
        double ts_arr_; // Required by Marker of JOBS 

        //Monarch extn begins
        nsaddr_t prev_hop_;     // IP addr of forwarding hop
        nsaddr_t next_hop_;     // next hop for this packet
        int      addr_type_;    // type of next_hop_ addr
        nsaddr_t last_hop_;     // for tracing on multi-user channels

        // called if pkt can't obtain media or isn't ack'd. not called if
        // droped by a queue
        FailureCallback xmit_failure_; 
        void *xmit_failure_data_;

        /*
         * MONARCH wants to know if the MAC layer is passing this back because
         * it could not get the RTS through or because it did not receive
         * an ACK.
         */
        int     xmit_reason_;
#define XMIT_REASON_RTS 0x01
#define XMIT_REASON_ACK 0x02

        // filled in by GOD on first transmission, used for trace analysis
        int num_forwards_;      // how many times this pkt was forwarded
        int opt_num_forwards_;   // optimal #forwards
        // Monarch extn ends;

        // tx time for this packet in sec
        double txtime_;
        inline double& txtime() { return(txtime_); }

        static int offset_;     // offset for this header
        inline static int& offset() { return offset_; }
        inline static hdr_cmn* access(const Packet* p) {
                return (hdr_cmn*) p->access(offset_);
        }
        
        /* per-field member functions */
        inline packet_t& ptype() { return (ptype_); }
        inline int& size() { return (size_); }
        inline int& uid() { return (uid_); }
        inline int& error() { return error_; }
        inline int& errbitcnt() {return errbitcnt_; }
        inline int& fecsize() {return fecsize_; }
        inline double& timestamp() { return (ts_); }
        inline int& iface() { return (iface_); }
        inline dir_t& direction() { return (direction_); }
        // monarch_begin
        inline nsaddr_t& next_hop() { return (next_hop_); }
        inline int& addr_type() { return (addr_type_); }
        inline int& num_forwards() { return (num_forwards_); }
        inline int& opt_num_forwards() { return (opt_num_forwards_); }
        //monarch_end
};


class PacketHeaderClass : public TclClass {
protected:
        PacketHeaderClass(const char* classname, int hdrsize);
        virtual int method(int argc, const char*const* argv);
        void field_offset(const char* fieldname, int offset);
        inline void bind_offset(int* off) { offset_ = off; }
        inline void offset(int* off) {offset_= off;}
        int hdrlen_;            // # of bytes for this header
        int* offset_;           // offset for this header
public:
        virtual void bind();
        virtual void export_offsets();
        TclObject* create(int argc, const char*const* argv);
};


inline void Packet::init(Packet* p)
{
        bzero(p->bits_, hdrlen_);
}

inline Packet* Packet::alloc()
{
        Packet* p = free_;
        if (p != 0) {
                assert(p->fflag_ == FALSE);
                free_ = p->next_;
                assert(p->data_ == 0);
                p->uid_ = 0;
                p->time_ = 0;
        } else {
                p = new Packet;
                p->bits_ = new unsigned char[hdrlen_];
                if (p == 0 || p->bits_ == 0)
                        abort();
        }
        init(p); // Initialize bits_[]
        (HDR_CMN(p))->next_hop_ = -2; // -1 reserved for IP_BROADCAST
        (HDR_CMN(p))->last_hop_ = -2; // -1 reserved for IP_BROADCAST
        p->fflag_ = TRUE;
        (HDR_CMN(p))->direction() = hdr_cmn::DOWN;
        /* setting all direction of pkts to be downward as default; 
           until channel changes it to +1 (upward) */
        p->next_ = 0;
        return (p);
}

/* 
 * Allocate an n byte data buffer to an existing packet 
 * 
 * To set application-specific AppData, use Packet::setdata()
 */
inline void Packet::allocdata(int n)
{
        assert(data_ == 0);
        data_ = new PacketData(n);
        if (data_ == 0)
                abort();
}

/* allocate a packet with an n byte data buffer */
inline Packet* Packet::alloc(int n)
{
        Packet* p = alloc();
        if (n > 0) 
                p->allocdata(n);
        return (p);
}


inline void Packet::free(Packet* p)
{
        if (p->fflag_) {
                if (p->ref_count_ == 0) {
                        /*
                         * A packet's uid may be < 0 (out of a event queue), or
                         * == 0 (newed but never gets into the event queue.
                         */
                        assert(p->uid_ <= 0);
                        // Delete user data because we won't need it any more.
                        if (p->data_ != 0) {
                                delete p->data_;
                                p->data_ = 0;
                        }
                        init(p);
                        p->next_ = free_;
                        free_ = p;
                        p->fflag_ = FALSE;
                } else {
                        --p->ref_count_;
                }
        }
}

inline Packet* Packet::copy() const
{
        
        Packet* p = alloc();
        memcpy(p->bits(), bits_, hdrlen_);
        if (data_) 
                p->data_ = data_->copy();
        p->txinfo_.init(&txinfo_);
 
        return (p);
}

inline void
Packet::dump_header(Packet *p, int offset, int length)
{
        assert(offset + length <= p->hdrlen_);
        struct hdr_cmn *ch = HDR_CMN(p);

        fprintf(stderr, "\nPacket ID: %d\n", ch->uid());

        for(int i = 0; i < length ; i+=16) {
                fprintf(stderr, "%02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
                        p->bits_[offset + i],     p->bits_[offset + i + 1],
                        p->bits_[offset + i + 2], p->bits_[offset + i + 3],
                        p->bits_[offset + i + 4], p->bits_[offset + i + 5],
                        p->bits_[offset + i + 6], p->bits_[offset + i + 7],
                        p->bits_[offset + i + 8], p->bits_[offset + i + 9],
                        p->bits_[offset + i + 10], p->bits_[offset + i + 11],
                        p->bits_[offset + i + 12], p->bits_[offset + i + 13],
                        p->bits_[offset + i + 14], p->bits_[offset + i + 15]);
        }
}

#endif

---