classifier-hash.h

Go to the documentation of this file.

/* -*-  Mode:C++; c-basic-offset:8; tab-width:8; indent-tabs-mode:t -*- */
/*
 * Copyright (c) 1997 The 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 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.
 * 
 * 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/classifier/classifier-hash.h,v 1.9 2005/09/18 23:33:31 tomh 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 long lookup(Packet* p) {
        hdr_ip* h = hdr_ip::access(p);
        return get_hash(mshift(h->saddr()), mshift(h->daddr()), 
                h->flowid());
    }
    virtual long 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;
    };
        
    long 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, long slot) {
        int newEntry;
        Tcl_HashEntry *ep= Tcl_CreateHashEntry(&ht_,
                               hashkey(src, dst, fid),
                               &newEntry); 
        if (ep) {
            Tcl_SetHashValue(ep, slot);
            return slot;
        }
        return -1;
    }
    long get_hash(nsaddr_t src, nsaddr_t dst, int fid) {
        Tcl_HashEntry *ep= Tcl_FindHashEntry(&ht_, 
                             hashkey(src, dst, fid)); 
        if (ep)
            return (long)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) {
        long key = fid;
        return (const char*) key;
    }
};

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) {
        long key = mshift(dst);
        return (const char*) key;
    }
};

---