/* 

                  Firewall Builder Routing add-on

                 Copyright (C) 2004 Compal GmbH, Germany

  Author:  Tidei Maurizio     <fwbuilder-routing at compal.de>
  
  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, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
  of the Software, and to permit persons to whom the Software is furnished to do
  so, subject to the following conditions: 

  The above copyright notice and this permission notice shall be included in all
  copies or substantial portions of the Software. 

  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
  INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
  PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
  OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 

*/

#include <assert.h>

#include "RoutingCompiler.h"

#include "fwbuilder/AddressRange.h"
#include "fwbuilder/RuleElement.h"
#include "fwbuilder/Network.h"
#include "fwbuilder/IPService.h"
#include "fwbuilder/ICMPService.h"
#include "fwbuilder/TCPService.h"
#include "fwbuilder/UDPService.h"
#include "fwbuilder/CustomService.h"
#include "fwbuilder/Routing.h"
#include "fwbuilder/Rule.h"
#include "fwbuilder/Firewall.h"
#include "fwbuilder/RuleSet.h"
#include "fwbuilder/IPAddress.h"
#include "fwbuilder/Interface.h"
#include "fwbuilder/IPv4.h"
#include "fwbuilder/FWObjectDatabase.h"
#include "fwbuilder/XMLTools.h"
#include "fwbuilder/FWException.h"
#include "fwbuilder/Group.h"

#include <iostream>
#include <iomanip>
#include <sstream>
#include <algorithm>
#include <assert.h>

 
using namespace fwcompiler;
using namespace libfwbuilder;
using namespace std;

int RoutingCompiler::prolog()
{
    Compiler::prolog();
    
    FWObject  *routing=fw->getFirstByType(Routing::TYPENAME);
    assert(routing);

    combined_ruleset = new Routing();   // combined ruleset
    fw->add( combined_ruleset );

    temp_ruleset = new Routing();   // working copy of the routing
    fw->add( temp_ruleset );

    
    list<FWObject*> l=routing->getByType(RoutingRule::TYPENAME);
    for (list<FWObject*>::iterator j=l.begin(); j!=l.end(); ++j) 
    {
	Rule *r= Rule::cast(*j);
	if (r->isDisabled()) continue;
	r->setInterfaceId("");
	r->setLabel( createRuleLabel("main", r->getPosition()) );
	combined_ruleset->add( r );
    }

    initialized=true;
    
    return combined_ruleset->size();
}


bool RoutingCompiler::cmpRules(const RoutingRule &r1,
                              const RoutingRule &r2)
{
    if (r1.getRDst()!=r2.getRDst()) return false;
    if (r1.getRGtw()!=r2.getRGtw()) return false;
    if (r1.getRItf()!=r2.getRItf()) return false;

    return true;
}


string RoutingCompiler::debugPrintRule(Rule *r)
{
    RoutingRule *rule=RoutingRule::cast(r);

    FWOptions *ruleopt =rule->getOptionsObject();

    RuleElementRDst *dstrel=rule->getRDst();
    RuleElementRItf *itfrel=rule->getRItf();
    RuleElementRGtw *gtwrel=rule->getRGtw();

    ostringstream str;

//    str << setw(70) << setfill('-') << "-";

    string dst, itf, gtw;
   
    FWObject* obj = itfrel;
    if (FWReference::cast(itfrel)!=NULL) obj=FWReference::cast( obj)->getPointer();
    itf=obj->getName();

    if (FWReference::cast(gtwrel)!=NULL) obj=FWReference::cast( obj)->getPointer();
    gtw=obj->getName();    
     
    
    int no=0;
    FWObject::iterator i1=dstrel->begin();
    while ( i1!=dstrel->end()) {

        str << endl;

        dst=" ";

        if (i1!=dstrel->end()) {
            FWObject *o=*i1;
            if (FWReference::cast(o)!=NULL) o=FWReference::cast(o)->getPointer();
            dst=o->getName();
        }

        int w=0;
        if (no==0) {
            str << rule->getLabel();
            w=rule->getLabel().length();
        }
        
        str <<  setw(10-w)  << setfill(' ') << " ";

        str <<  setw(18) << setfill(' ') << dst.c_str();
        str <<  setw(18) << setfill(' ') << itf.c_str();
        str <<  setw(12) << setfill(' ') << gtw.c_str();
        str <<  setw(18) << setfill(' ') << " ";

        ++no;

        if ( i1!=dstrel->end() ) ++i1;
    }
    return str.str();
}


bool RoutingCompiler::ExpandMultipleAddresses::processNext()
{
    RoutingRule *rule=getNext(); if (rule==NULL) return false;

    tmp_queue.push_back(rule);

    RuleElementRDst *dst=rule->getRDst();    assert(dst);
    RuleElementRGtw *gtw=rule->getRGtw();    assert(gtw);
    
    compiler->_expandAddr(rule,dst);
    compiler->_expandAddr(rule,gtw);

    return true;
}


bool RoutingCompiler::ConvertToAtomicForDST::processNext()
{
    RoutingRule *rule=getNext(); if (rule==NULL) return false;

    //RuleElementSrc *src=rule->getSrc();    assert(src);
    RuleElementRDst *dst=rule->getRDst();    assert(dst);


    for (FWObject::iterator it=dst->begin(); it!=dst->end(); ++it) {

        RoutingRule *r = RoutingRule::cast(
            compiler->dbcopy->create(RoutingRule::TYPENAME) );
        r->duplicate(rule);
        compiler->temp_ruleset->add(r);

        FWObject *s;
        //s=r->getSrc();	assert(s);
        //s->clearChildren();
        //s->add( *i1 );

        s=r->getRDst();	assert(s);
        s->clearChildren();
        s->add( *it );

        tmp_queue.push_back(r);
    }

    return true;
}


bool RoutingCompiler::ExpandGroups::processNext()
{
    RoutingRule *rule=getNext(); if (rule==NULL) return false;

    tmp_queue.push_back(rule);

    RuleElementRDst *dst=rule->getRDst();   assert(dst);
    
    compiler->expandGroupsInRuleElement(dst);

    return true;
}


bool RoutingCompiler::emptyRDstAndRItf::processNext()
{
    RoutingRule *rule=getNext(); if (rule==NULL) return false;
    
    tmp_queue.push_back(rule);
    
    
    RuleElementRGtw *gtwrel=rule->getRGtw();
    RuleElementRItf *itfrel=rule->getRItf();

    if ( (FWReference::cast(itfrel->front())->getPointer())->getStr("name")=="Any" &&\
         (FWReference::cast(gtwrel->front())->getPointer())->getStr("name")=="Any") {
        
        string msg;
        msg = "Gateway and interface are both empty in the rule " + rule->getLabel();
        compiler->abort( msg.c_str() );
    }

    return true;
}


bool RoutingCompiler::singleAdressInRGtw::processNext()
{
    RoutingRule *rule=getNext(); if (rule==NULL) return false;
    
    tmp_queue.push_back(rule);
    
    
    RuleElementRGtw *gtwrel=rule->getRGtw();
    FWObject *o = FWReference::cast(gtwrel->front())->getPointer();
              
    if( gtwrel->checkSingleIPAdress(o) == false) {
        
        string msg;
        msg = "The object \"" + o->getStr("name") + "\" used as gateway in the routing rule "\
            + rule->getLabel() + " has more than one interface resp. IP adress!";
        compiler->abort( msg.c_str() );
        
    }
    return true;
}

// recursive network validity check
bool RoutingCompiler::validateNetwork::checkValidNetwork(FWObject *o) {
    
    if( Network::cast(o) != NULL) {
        return ((Network *)o)->isValidRoutingNet();
    }
    
    /* if we have a group containing networks and groups, we want to check them too */
    if( ObjectGroup::cast(o) != NULL) {
        
        FWObjectTypedChildIterator child_i = o->findByType(FWObjectReference::TYPENAME);
        for ( ; child_i != child_i.end(); ++child_i) {
            FWObjectReference *child_r = FWObjectReference::cast(*child_i);
            assert(child_r);
            FWObject *child = child_r->getPointer();
            
            Network *network;
            ObjectGroup *group;
            
            // Network
            if ((network=Network::cast(child)) != NULL) {
                if (checkValidNetwork(network) == false) {
                    return false;
                }
            } else if ((group=ObjectGroup::cast(child)) != NULL) { // Group
                if (checkValidNetwork(group) == false) {
                    return false;
                }
            }
        }
    }
    
    return true;    
}

// Invalid routing destination network: network address and netmask mismatch. 
bool RoutingCompiler::validateNetwork::processNext()
{
    RoutingRule *rule=getNext(); if (rule==NULL) return false;
    
    tmp_queue.push_back(rule);
    
    RuleElementRDst *dstrel=rule->getRDst();
    FWObject *o = FWReference::cast(dstrel->front())->getPointer();
     
    if( checkValidNetwork(o) == false) {
    
        string msg;
        msg = "The object \"" + o->getStr("name") + "\" used as destination in the routing rule "\
            + rule->getLabel() + " has an invalid netmask!";
        compiler->abort( msg.c_str() );
        
    }
    return true;
    
}

//  the IP address of the gateway has to be in a local network of the firewall
bool RoutingCompiler::reachableAdressInRGtw::processNext()
{
    RoutingRule *rule=getNext(); if (rule==NULL) return false;
    
    tmp_queue.push_back(rule);
    
    
    RuleElementRGtw *gtwrel=rule->getRGtw();
    FWObject *o = FWReference::cast(gtwrel->front())->getPointer();
              
    if( gtwrel->checkReachableIPAdress(o) == false) {
        
        string msg;
        msg = "The object \"" + o->getStr("name") + "\" used as gateway in the routing rule "\
            + rule->getLabel() + " is not reachable, since not in any local network of the firewall!";
        compiler->abort( msg.c_str() );
        
    }
    return true;
}

// the IP address of the gateway RGtw has to be in a network of the interface RItf
bool RoutingCompiler::contradictionRGtwAndRItf::processNext()
{
    RoutingRule *rule=getNext(); if (rule==NULL) return false;
    
    tmp_queue.push_back(rule);
    
    RuleElementRGtw *gtwrel=rule->getRGtw();
    RuleElementRItf *itfrel=rule->getRItf();
    
    FWObject *oRGtw = FWReference::cast(gtwrel->front())->getPointer();
    FWObject *oRItf = FWReference::cast(itfrel->front())->getPointer();
    
    if (oRItf->getStr("name") == "Any") { return true; }
    
    
    if( Host::cast(oRGtw) != NULL || Interface::cast(oRGtw) != NULL || IPv4::cast(oRGtw) != NULL) {

        IPAddress ip_interface;

        if ( Host::cast(oRGtw) != NULL) {
            Host *host=Host::cast(oRGtw);
            ip_interface= host->getAddress();
        } else if (Interface::cast(oRGtw) != NULL) {
            Interface *intf=Interface::cast(oRGtw);
            ip_interface= intf->getAddress();
        } else if (IPv4::cast(oRGtw) != NULL) {
            IPv4 *ipv4=IPv4::cast(oRGtw);
            ip_interface= ipv4->getAddress();
        }

        
        list<FWObject*> obj_list = oRItf->getByType("IPv4");
        for (list<FWObject*>::iterator i=obj_list.begin(); i!=obj_list.end(); ++i) 
        {
            IPv4 *firewall=IPv4::cast(*i); 
            Netmask n_firewall = firewall->getNetmask();
            IPAddress ip_firewall = firewall->getAddress();
             
            if ((n_firewall.to32BitInt() & ip_firewall.to32BitInt()) == (n_firewall.to32BitInt() & ip_interface.to32BitInt())) {
                return true;
            }
        }

        string msg;
        msg = "The object \"" + oRGtw->getStr("name") + "\" used as gateway in the routing rule "\
            + rule->getLabel() + " is not in the same local network as the interface " + oRItf->getStr("name") + "!";
        compiler->abort( msg.c_str() );

    }

    return true;

}

bool RoutingCompiler::rItfChildOfFw::processNext()
{
    RoutingRule *rule=getNext(); if (rule==NULL) return false;
    
    tmp_queue.push_back(rule);
    
    
    RuleElementRItf *itfrel=rule->getRItf();
    FWObject *o = FWReference::cast(itfrel->front())->getPointer();
              
    if( itfrel->checkItfChildOfThisFw(o) == false) {
        
        string msg;
        msg = "The object \"" + o->getStr("name") + "\" used as interface in the routing rule "\
            + rule->getLabel() + " is not a child of the firewall the rule belongs to!";
        compiler->abort( msg.c_str() );
        
    } 
    return true;
}


bool RoutingCompiler::competingRules::processNext()
{
    RoutingRule *rule=getNext(); if (rule==NULL) return false;

        
    RuleElementRItf *itfrel=rule->getRItf();
    FWObject *itf = FWReference::cast(itfrel->front())->getPointer();
    
    RuleElementRGtw *gtwrel=rule->getRGtw();
    FWObject *gtw = FWReference::cast(gtwrel->front())->getPointer();
     
    RuleElementRDst *dstrel=rule->getRDst();
    
    string metric = rule->getMetricAsString();
    string label  = rule->getSortedDstIds();
    string combiId = gtw->getStr("id") + itf->getStr("id");
    
    if( label == "") compiler->abort("Place 'createSortedDstIdsLabel()' before 'competingRules()' in the rule processor chain!");
    
    dest_it = rules_seen_so_far.find(label);
    if( dest_it != rules_seen_so_far.end()) {
        
        // a rule with the same destination was already seen
        ///std::cout << "NO NEW DEST" << std::endl;
        
        gtwitf_it = dest_it->second.find(combiId);
        if( gtwitf_it != dest_it->second.end() ) {
            
            // ... this gateway and interface combination were already seen for this destination
            ///std::cout << "NO NEW GTWITF" << std::endl;
            
            if( gtwitf_it->second.first == metric) {
                
                // ... and same metric => rule already exists, skip
                ///std::cout << "SAME METRIC" << std::endl;
                
                string msg;
                msg = "The routing rules " + gtwitf_it->second.second + " and " + rule->getLabel() +
                      "are identical,\n skipping the second. Please delete one of them to avoid this warning!";
                compiler->warning( msg.c_str() );
            
            } else {
                
                // ... but different metric => what metric should I use? => abort
                ///std::cout << "DIFFERENT METRIC" << std::endl;
                
                string msg;
                msg = "The routing rules " + gtwitf_it->second.second + " and " + rule->getLabel() +
                      "are identical\n except the metric, please delete one of them!";
                compiler->abort( msg.c_str() );
            }
        
        } else {

            // ... this gateway and interface combination is new for this destination
            ///std::cout << "NEW GTWITF" << std::endl;///
            
            if(false) {
                // TODO_lowPrio: if ( !compiler->fw->getOptionsObject()->getBool ("equal_cost_multi_path") ) ...If multipath is turned off, perform this check.
                //               iterate all gtwitf combis in the map dest_it->second and search for the current metric
                
                // ... but has the same metric => what route should I use for this destination? => abort
                
                
                    
                string msg;
                msg = "The routing rules " + gtwitf_it->second.second + " and " + rule->getLabel() + " have the same destination,\
                    \na different gateway and interface combination, but the same metric.\
                    \nPlease set the metrics to different values or enable ECMP (Equal Cost MultiPath) routing!";
                compiler->abort( msg.c_str() );
            
            } else {
                
                // ... and different metric OR equal_cost_multi_path enabled => OK
                
                tmp_queue.push_back(rule);
            }
            
            dest_it->second[combiId] = pair< string, string>( metric, rule->getLabel());
        }
        
    } else {
        
        // this destination is new
        //std::cout << "NEW DEST" << std::endl;
        ///
        
        //ruleinfo tmpRuleInfo = { gtw->getStr("id") + itf->getStr("id"), metric, rule->getLabel()};
        //rules_seen_so_far[label] = tmpRuleInfo;
        
        map< string, pair< string, string> > gtw_itf_tmp;
        gtw_itf_tmp[combiId] = pair< string, string>( metric, rule->getLabel());
        
        rules_seen_so_far[label] = gtw_itf_tmp;
        
        
        tmp_queue.push_back(rule);
    }

    return true;
}


bool RoutingCompiler::classifyRoutingRules::processNext()
{

    assert(compiler!=NULL);
    assert(prev_processor!=NULL);

    slurp();

    if (tmp_queue.size()==0) return false;
    
    
    for (std::deque<libfwbuilder::Rule *>::iterator tmp_queue_it=tmp_queue.begin(); tmp_queue_it!=tmp_queue.end(); ++tmp_queue_it) {
        
        RoutingRule *rule = RoutingRule::cast( *tmp_queue_it);
        rule->setRuleType( RoutingRule::SinglePath);
        
        RuleElementRItf *itfrel=rule->getRItf();
        FWObject *itf = FWReference::cast(itfrel->front())->getPointer();
        
        RuleElementRGtw *gtwrel=rule->getRGtw();
        FWObject *gtw = FWReference::cast(gtwrel->front())->getPointer();
        
        RuleElementRDst *dstrel=rule->getRDst();
        
        string metric  = rule->getMetricAsString();
        string label   = rule->getSortedDstIds();
        string combiId = gtw->getStr("id") + itf->getStr("id");
        
        if( label == "") compiler->abort("Place 'createSortedDstIdsLabel()' right before 'classifyRoutingRules()' in the rule processor chain!");
        
        dest_it = rules_seen_so_far.find(label);
        if( dest_it != rules_seen_so_far.end()) {
            
            // a rule with the same destination was already seen
            //std::cout << "classifyRoutingRules:NO NEW DEST" << std::endl;///
            
            gtwitf_it = dest_it->second.find(combiId);
            if( gtwitf_it == dest_it->second.end() ) {
                
                // ... this gateway and interface combination is new for this destination
                //std::cout << "classifyRoutingRules:NEW GTWITF" << std::endl;///
                
                
                for( gtwitf_it = dest_it->second.begin(); gtwitf_it != dest_it->second.end(); gtwitf_it++) {
                    
                    if( gtwitf_it->second.first == metric) {
                        // ... but has the same metric as another rule with this Dst => multipath or abort
                        //std::cout << "classifyRoutingRules:SAME METRIC" << std::endl;///
                        
                        if(true) { //TODO: if ( compiler->fw->getOptionsObject()->getBool ("equal_cost_multi_path") )
                            
                            rule->setRuleType( RoutingRule::MultiPath);
                            gtwitf_it->second.second->setRuleType( RoutingRule::MultiPath);
                            
                            //std::cout << "classifyRoutingRules:the rules " << rule->getLabel() << " and " << gtwitf_it->second.second->getLabel() << " were set to multipath." << std::endl;///
                        }
                    }
                }
                
                dest_it->second[combiId] = pair< string, RoutingRule*>( metric, rule);
            }
            
        } else {
            
            // this destination is new
            //std::cout << "classifyRoutingRules:NEW DEST" << std::endl;///
             
            map< string, pair< string, RoutingRule*> > gtw_itf_tmp;
            gtw_itf_tmp[combiId] = pair< string, RoutingRule*>( metric, rule);
            rules_seen_so_far[label] = gtw_itf_tmp;
        }
    }
    
    return true;
}


bool RoutingCompiler::createSortedDstIdsLabel::processNext()
{
    RoutingRule *rule=getNext(); if (rule==NULL) return false;
    
    tmp_queue.push_back(rule);
    
    // create a label with a sorted dst-id-list, to find identical destinations even if the order 
    // of the dst objects differs within one rule
    
    RuleElementRDst *dstrel=rule->getRDst();
              
    string label = rule->getLabel();
    int bracepos = label.find("(");
    label.erase(0, bracepos);   
             
    std::list<string> idList;
    for (FWObject::iterator it=dstrel->begin(); it!=dstrel->end(); ++it) {
        
        idList.insert(idList.end(), (FWReference::cast(*it)->getPointer())->getStr("id"));
    }
    idList.sort();
    for (std::list<string>::iterator it=idList.begin(); it!=idList.end(); ++it) {
        
        label += " " + *it;
    }
    ///std::cout << "createDstLabel:LABEL: '" << label << "'" << endl;
    
    rule->setSortedDstIds( label);
    
    return true;
}