classifier-hash.h

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/* -*-  Mode:C++; c-basic-offset:8; tab-width:8; indent-tabs-mode:t -*- */
/*
 * Copyright (c) 1997 The Regents of the University of California.
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 * 1. Redistributions of source code must retain the above copyright
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 *    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 Network Research
 *      Group at Lawrence Berkeley National 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.
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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 * $Header: /nfs/jade/vint/CVSROOT/ns-2/classifier/classifier-hash.h,v 1.8 2002/01/25 20:22:15 haldar Exp $
 */

#include "classifier.h"
#include "ip.h"

class Flow;

/* class defs for HashClassifier (base), SrcDest, SrcDestFid HashClassifiers */
class HashClassifier : public Classifier {
public:
        HashClassifier(int keylen) : default_(-1), keylen_(keylen) {
                // shift + mask picked up from underlying Classifier object
                bind("default_", &default_);
                Tcl_InitHashTable(&ht_, keylen);
        }               
        ~HashClassifier() {
                Tcl_DeleteHashTable(&ht_);
        };
        virtual int classify(Packet *p);
        virtual int lookup(Packet* p) {
                hdr_ip* h = hdr_ip::access(p);
                return get_hash(mshift(h->saddr()), mshift(h->daddr()), 
                                h->flowid());
        }
        virtual int unknown(Packet* p) {
                hdr_ip* h = hdr_ip::access(p);
                Tcl::instance().evalf("%s unknown-flow %u %u %u",
                                      name(), h->saddr(), h->daddr(),
                                      h->flowid()); 
                return lookup(p);
        };
        void set_default(int slot) { default_ = slot; } 
        int do_set_hash(nsaddr_t src, nsaddr_t dst, int fid, int slot) {
                return (set_hash(src,dst,fid,slot));
        }
        void set_table_size(int nn) {}
protected:
        union hkey {
                struct {
                        int fid;
                } Fid;
                struct {
                        nsaddr_t dst;
                } Dst;
                struct {
                        nsaddr_t src, dst;
                } SrcDst;
                struct {
                        nsaddr_t src, dst;
                        int fid;
                } SrcDstFid;
        };
                
        int lookup(nsaddr_t src, nsaddr_t dst, int fid) {
                return get_hash(src, dst, fid);
        }
        int newflow(Packet* pkt) {
                hdr_ip* h = hdr_ip::access(pkt);
                Tcl::instance().evalf("%s unknown-flow %u %u %u",
                                      name(), h->saddr(), h->daddr(),
                                      h->flowid()); 
                return lookup(pkt);
        };
        void reset() {
                Tcl_DeleteHashTable(&ht_);
                Tcl_InitHashTable(&ht_, keylen_);
        }

        virtual const char* hashkey(nsaddr_t, nsaddr_t, int)=0; 

        int set_hash(nsaddr_t src, nsaddr_t dst, int fid, int slot) {
                int newEntry;
                Tcl_HashEntry *ep= Tcl_CreateHashEntry(&ht_,
                                                       hashkey(src, dst, fid),
                                                       &newEntry); 
                if (ep) {
                        Tcl_SetHashValue(ep, slot);
                        return slot;
                }
                return -1;
        }
        int get_hash(nsaddr_t src, nsaddr_t dst, int fid) {
                Tcl_HashEntry *ep= Tcl_FindHashEntry(&ht_, 
                                                     hashkey(src, dst, fid)); 
                if (ep)
                        return (int)Tcl_GetHashValue(ep);
                return -1;
        }
        
        virtual int command(int argc, const char*const* argv);


        int default_;
        Tcl_HashTable ht_;
        hkey buf_;
        int keylen_;
};

class SrcDestFidHashClassifier : public HashClassifier {
public:
        SrcDestFidHashClassifier() : HashClassifier(3) {
        }
protected:
        const char* hashkey(nsaddr_t src, nsaddr_t dst, int fid) {
                buf_.SrcDstFid.src= mshift(src);
                buf_.SrcDstFid.dst= mshift(dst);
                buf_.SrcDstFid.fid= fid;
                return (const char*) &buf_;
        }
};

class SrcDestHashClassifier : public HashClassifier {
public:
        SrcDestHashClassifier() : HashClassifier(2) {
        int command(int argc, const char*const* argv);
        int classify(Packet *p);
        }
protected:
        const char*  hashkey(nsaddr_t src, nsaddr_t dst, int) {
                buf_.SrcDst.src= mshift(src);
                buf_.SrcDst.dst= mshift(dst);
                return (const char*) &buf_;
        }
};

class FidHashClassifier : public HashClassifier {
public:
        FidHashClassifier() : HashClassifier(TCL_ONE_WORD_KEYS) {
        }
protected:
        const char* hashkey(nsaddr_t, nsaddr_t, int fid) {
                return (const char*) fid;
        }
};

class DestHashClassifier : public HashClassifier {
public:
        DestHashClassifier() : HashClassifier(TCL_ONE_WORD_KEYS) {}
        virtual int command(int argc, const char*const* argv);
        int classify(Packet *p);
        virtual void do_install(char *dst, NsObject *target);
protected:
        const char* hashkey(nsaddr_t, nsaddr_t dst, int) {
                return (const char*) mshift(dst);
        }
};

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