routingtable.cc

RSA algorithm implementation is given

#include "common.h"
#include "externDec.h"


/* This function does routing table initialization */
int routingTable::init_KRT ()
{
	  rtable_entry	rtEntry;

	  rtEntry.createEntry(g_my_ip,g_my_ip,localSeqNum,0,(getcurrtime()+ROUTE_TIMEOUT),0); 

#ifdef DEBUG
	  cout << "Inside initRT" << endl;
#endif

	  /* Insert entry for the local node in both the routing tables */
	  rTableMap.insert(pair<u_int32_t,rtable_entry>(rtEntry.getDestIP(),rtEntry));

	  /* add this entry to the kernel routing table */
	  add_kroute(rtEntry);
	  return 0;
}

/* This function does routing table initialization */
int routingTable::init_RT ()
{
	  rtable_entry	rtEntry;

	  rtEntry.createEntry(g_my_ip,g_my_ip,localSeqNum,0,(getcurrtime()+ROUTE_TIMEOUT),0); 

#ifdef DEBUG
	  cout << "Inside initRT" << endl;
#endif

	  /* Insert entry for the local node in both the routing tables */
	  rTableMap.insert(pair<u_int32_t,rtable_entry>(rtEntry.getDestIP(),rtEntry));

	  return 0;
}


void	routingTable::incrementLocalSeqNum()
{
	map<u_int32_t,rtable_entry>::iterator	iter;

	iter = rTableMap.find(g_my_ip);
	if(iter != rTableMap.end())
	{
		iter->second.setDestSeqNum(genSeqNum());
	}
}

u_int32_t	routingTable::genSeqNum()
{
	localSeqNum+=2;
	return localSeqNum;
}

void	routingTable::setLocalSeqNum()
{
	map<u_int32_t,rtable_entry>::iterator	iter;

	iter = rTableMap.find(g_my_ip);
	if(iter != rTableMap.end())
	{
		iter->second.setDestSeqNum(localSeqNum);
	}
}

rtable_entry *	routingTable::findRoute(u_int32_t dst)
{

	map<u_int32_t,rtable_entry>::iterator	iter;

	iter = rTableMap.find(dst);
	if(iter != rTableMap.end())
		return &(iter->second);
	else
		return NULL;
}

void	routingTable::insertRoute(rtable_entry rtEntry)
{
	  rTableMap.insert(pair<u_int32_t,rtable_entry>(rtEntry.getDestIP(),rtEntry));
	  //add_kroute(rtEntry);
}

u_int8_t	routingTable::getSize()
{
	return rTableMap.size();
}


void	routingTable::generateUpdateMessage(updateMessage *umsg, bool full_dump)
{

	/* if it is a full dump, reset the chang bit to 0 in the routing flag */

	u_int32_t	temp_flag=0;
	u_int8_t	count=0;

	umsg->setType(DSDV_PERIODIC_UPDATE);

	map<u_int32_t,rtable_entry>::iterator	iter, iter_temp;

#ifdef DEBUG
	cout << "routingTable: generateUpdateMessage: entered" << endl;
#endif

	/* first put the local node entry */
	iter_temp = rTableMap.find(g_my_ip);
	if(iter_temp != rTableMap.end())
	{
		umsg->insertIntoList(iter_temp->second.getDestIP(), iter_temp->second.getDestSeqNum(), iter_temp->second.getRTMetric());
		count++;
		
	}

	iter=rTableMap.begin();

	while(iter!=rTableMap.end())
	{
#ifdef DEBUG
		cout << "routingTable: generateUpdateMessage: inside while" << endl;
#endif

		if(iter->second.getDestIP() != g_my_ip)
		{
#ifdef DEBUG
			cout << "routingTable: generateUpdateMessage: not the local entry" << endl;
			cout << "routingTable: generateUpdateMessage: dest ip is" << getDotIP(iter->second.getDestIP()) << endl;
#endif

			if(full_dump)
			{
				umsg->insertIntoList(iter->second.getDestIP(), iter->second.getDestSeqNum(), iter->second.getRTMetric());
				count++;
				iter->second.setRFlags(0);
			}
			else
			{
				/* check if the change flag is set to 1 */
				temp_flag = iter->second.getRFlags();
				temp_flag = temp_flag >> 31;
				if(temp_flag == 1)
				{
#ifdef DEBUG
					cout << "generateUpdateMessage: change flag is set " << endl;
#endif
					umsg->insertIntoList(iter->second.getDestIP(), iter->second.getDestSeqNum(), iter->second.getRTMetric());
					count++;
				}
			}
		}
		iter++;
	}

	umsg->setEntriesCnt(count);
	return;
}

u_int8_t	routingTable::getChangedEntriesCnt()
{
	u_int32_t	temp_flag=0;
	u_int8_t	temp_cnt=0;

	map<u_int32_t,rtable_entry>::iterator	iter;
	iter=rTableMap.begin();

	while(iter!=rTableMap.end())
	{
		temp_flag = iter->second.getRFlags();
		temp_flag = temp_flag >> 31;
		if(temp_flag == 1)
		{
			temp_cnt++;
		}
		iter++;
	}
	return temp_cnt;
}


void	routingTable::syncRTables(u_int32_t dst)
{
	map<u_int32_t,rtable_entry>::iterator	iterFw;

	iterFw = rTableMap.find(dst);

	if(iterFw != rTableMap.end())
	{
		rtable_entry	*rtEntry;
		rtEntry = rTableBroadcast.findRoute(dst);

		if(rtEntry != NULL)
		{
			rtEntry->updateEntry(iterFw->second);
		}
		else
		{
			rTableBroadcast.addEntry(iterFw->second);
		}
	}
	return;
}

void	routingTable::addEntry(rtable_entry rtEntry)
{
	rTableMap.insert(pair<u_int32_t,rtable_entry>(rtEntry.getDestIP(),rtEntry));
	return;
}

void	routingTable::deleteEntry(u_int32_t dst)
{
	map<u_int32_t,rtable_entry>::iterator	iter;

	iter = rTableMap.find(dst);
	if(iter != rTableMap.end())
	{
#ifdef DEBUG
		cout << "routingTable:: deleteEntry: delete entry " << getDotIP(dst) << endl;
#endif
		rTableMap.erase(iter);
	}
	return;
}

bool	routingTable::refreshEntries()
{
	bool	doBroadcast=false;

	u_int64_t	currtime=getcurrtime();
	u_int32_t	prevMetric;

	map<u_int32_t,rtable_entry>::iterator	iter, temp_iter, iter_new;
	iter=rTableMap.begin();

	while(iter!=rTableMap.end())
	{
		iter++;
		temp_iter=iter;
		iter--;

		if(iter->second.getDestIP() != g_my_ip)
		{
			if(iter->second.getLifeTime() <= currtime)
			{
#ifdef DEBUG
				cout << "routingTable: expire the entry " << endl;
#endif

				if(iter->second.getRTMetric() == INFINITY)
				{
					rTableBroadcast.deleteEntry(iter->second.getDestIP());
					rTableMap.erase(iter);
				}
				else
				{
					/* delete entry from the kernel */
					del_kroute(iter->second);

					stlTable.deleteEntry(iter->second.getDestIP());

					doBroadcast=true;

					prevMetric = iter->second.getRTMetric();

					/* set metric to infinity and increment the sequence number */
					iter->second.setRTMetric(INFINITY);
					iter->second.setDestSeqNum(iter->second.getDestSeqNum()+1);

					/* set the change bit in the routing flag */
					u_int32_t	temp_flag=1;
					temp_flag = temp_flag << 31;
					iter->second.setRFlags(temp_flag);

					syncRTables(iter->second.getDestIP());

					if(prevMetric == 1)
					{
#ifdef DEBUG
						cout << "routingTable: refreshEntries: one hop heighbor " << endl;
#endif

						iter_new = rTableMap.begin();
						while(iter_new != rTableMap.end())
						{
							if((iter_new->second.getRTMetric()!= INFINITY) &&
							(iter_new->second.getNextHop() == iter->second.getDestIP()))
							{
								del_kroute(iter_new->second);
								

								/* set metric to infinity and increment 
								 * the sequence number */
								iter_new->second.setRTMetric(INFINITY);
								iter_new->second.setDestSeqNum(iter_new->second.getDestSeqNum()+1);

								/* set the change bit in the routing flag */
								u_int32_t	temp_flag=1;
								temp_flag = temp_flag << 31;
								iter_new->second.setRFlags(temp_flag);

								syncRTables(iter_new->second.getDestIP());
							}
							iter_new++;
						}
					}
				}
			}
		}
		else
		{
#ifdef DEBUG
			cout << "routingTable: local entry expires, reset lifetime " << endl;
#endif
			iter->second.setLifeTime(ROUTE_TIMEOUT);
		}
		iter=temp_iter;
	}
	return doBroadcast;
}