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Port TcpReassembly example to C++11 (#1229)
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@jpcofr
jpcofr authored Nov 9, 2023
1 parent 3227ad1 commit 813f15b
Showing 1 changed file with 52 additions and 55 deletions.
107 changes: 52 additions & 55 deletions Examples/TcpReassembly/main.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -23,8 +23,7 @@


#include <stdlib.h>
#include <stdio.h>
#include <map>
#include <unordered_map>
#include <iostream>
#include <fstream>
#include <sstream>
Expand Down Expand Up @@ -53,8 +52,7 @@


// unless the user chooses otherwise - default number of concurrent used file descriptors is 500
#define DEFAULT_MAX_NUMBER_OF_CONCURRENT_OPEN_FILES 500

constexpr int DEFAULT_MAX_NUMBER_OF_CONCURRENT_OPEN_FILES = 500;

static struct option TcpAssemblyOptions[] =
{
Expand Down Expand Up @@ -83,7 +81,7 @@ class GlobalConfig
/**
* A private c'tor (as this is a singleton)
*/
GlobalConfig() { writeMetadata = false; writeToConsole = false; separateSides = false; maxOpenFiles = DEFAULT_MAX_NUMBER_OF_CONCURRENT_OPEN_FILES; m_RecentConnsWithActivity = nullptr; }
GlobalConfig() : m_RecentConnsWithActivity(nullptr), writeMetadata(false), writeToConsole(false), separateSides(false), maxOpenFiles(DEFAULT_MAX_NUMBER_OF_CONCURRENT_OPEN_FILES) { }

// A least-recently-used (LRU) list of all connections seen so far. Each connection is represented by its flow key. This LRU list is used to decide which connection was seen least
// recently in case we reached max number of open file descriptors and we need to decide which files to close
Expand Down Expand Up @@ -111,7 +109,7 @@ class GlobalConfig
* A method getting connection parameters as input and returns a filename and file path as output.
* The filename is constructed by the IPs (src and dst) and the TCP ports (src and dst)
*/
std::string getFileName(pcpp::ConnectionData connData, int side, bool separareSides)
std::string getFileName(pcpp::ConnectionData connData, int side, bool useSeparateSides) const
{
std::stringstream stream;

Expand All @@ -127,7 +125,7 @@ class GlobalConfig
std::replace(destIP.begin(), destIP.end(), ':', '_');

// side == 0 means data is sent from client->server
if (side <= 0 || separareSides == false)
if (side <= 0 || !useSeparateSides)
stream << sourceIP << '.' << connData.srcPort << '-' << destIP << '.' << connData.dstPort;
else // side == 1 means data is sent from server->client
stream << destIP << '.' << connData.dstPort << '-' << sourceIP << '.' << connData.srcPort;
Expand All @@ -141,7 +139,7 @@ class GlobalConfig
* Open a file stream. Inputs are the filename to open and a flag indicating whether to append to an existing file or overwrite it.
* Return value is a pointer to the new file stream
*/
std::ostream* openFileStream(const std::string &fileName, bool reopen)
std::ostream* openFileStream(const std::string &fileName, bool reopen) const
{
// if the user chooses to write only to console, don't open anything and return std::cout
if (writeToConsole)
Expand All @@ -158,13 +156,13 @@ class GlobalConfig
/**
* Close a file stream
*/
void closeFileSteam(std::ostream* fileStream)
void closeFileSteam(std::ostream* fileStream) const
{
// if the user chooses to write only to console - do nothing and return
if (!writeToConsole)
{
// close the file stream
std::ofstream* fstream = (std::ofstream*)fileStream;
auto fstream = (std::ofstream*)fileStream;
fstream->close();

// free the memory of the file stream
Expand Down Expand Up @@ -246,7 +244,7 @@ struct TcpReassemblyData
}

/**
* Clear all data (put 0, false or NULL - whatever relevant for each field)
* Clear all data (put 0, false or nullptr - whatever relevant for each field)
*/
void clear()
{
Expand Down Expand Up @@ -276,9 +274,8 @@ struct TcpReassemblyData
};


// typedef representing the connection manager and its iterator
typedef std::map<uint32_t, TcpReassemblyData> TcpReassemblyConnMgr;
typedef std::map<uint32_t, TcpReassemblyData>::iterator TcpReassemblyConnMgrIter;
// typedef representing the connection manager
typedef std::unordered_map<uint32_t, TcpReassemblyData> TcpReassemblyConnMgr;


/**
Expand Down Expand Up @@ -326,12 +323,13 @@ void printAppVersion()
*/
void listInterfaces()
{
const std::vector<pcpp::PcapLiveDevice*>& devList = pcpp::PcapLiveDeviceList::getInstance().getPcapLiveDevicesList();
auto const& devList = pcpp::PcapLiveDeviceList::getInstance().getPcapLiveDevicesList();

std::cout << std::endl << "Network interfaces:" << std::endl;
for (std::vector<pcpp::PcapLiveDevice*>::const_iterator iter = devList.begin(); iter != devList.end(); iter++)

for (auto dev : devList)
{
std::cout << " -> Name: '" << (*iter)->getName() << "' IP address: " << (*iter)->getIPv4Address().toString() << std::endl;
std::cout << " -> Name: '" << dev->getName() << "' IP address: " << dev->getIPv4Address().toString() << std::endl;
}
exit(0);
}
Expand All @@ -340,17 +338,17 @@ void listInterfaces()
/**
* The callback being called by the TCP reassembly module whenever new data arrives on a certain connection
*/
static void tcpReassemblyMsgReadyCallback(int8_t sideIndex, const pcpp::TcpStreamData& tcpData, void* userCookie)
static void tcpReassemblyMsgReadyCallback(const int8_t sideIndex, const pcpp::TcpStreamData& tcpData, void* userCookie)
{
// extract the connection manager from the user cookie
TcpReassemblyConnMgr* connMgr = (TcpReassemblyConnMgr*)userCookie;
auto connMgr = (TcpReassemblyConnMgr*)userCookie;

// check if this flow already appears in the connection manager. If not add it
TcpReassemblyConnMgrIter iter = connMgr->find(tcpData.getConnectionData().flowKey);
if (iter == connMgr->end())
auto flow = connMgr->find(tcpData.getConnectionData().flowKey);
if (flow == connMgr->end())
{
connMgr->insert(std::make_pair(tcpData.getConnectionData().flowKey, TcpReassemblyData()));
iter = connMgr->find(tcpData.getConnectionData().flowKey);
flow = connMgr->find(tcpData.getConnectionData().flowKey);
}

int8_t side;
Expand All @@ -362,9 +360,9 @@ static void tcpReassemblyMsgReadyCallback(int8_t sideIndex, const pcpp::TcpStrea
side = 0;

// if the file stream on the relevant side isn't open yet (meaning it's the first data on this connection)
if (iter->second.fileStreams[side] == nullptr)
if (flow->second.fileStreams[side] == nullptr)
{
// add the flow key of this connection to the list of open connections. If the return value isn't NULL it means that there are too many open files
// add the flow key of this connection to the list of open connections. If the return value isn't nullptr it means that there are too many open files
// and we need to close the connection with least recently used file(s) in order to open a new one.
// The connection with the least recently used file is the return value
uint32_t flowKeyToCloseFiles;
Expand All @@ -374,20 +372,20 @@ static void tcpReassemblyMsgReadyCallback(int8_t sideIndex, const pcpp::TcpStrea
if (result == 1)
{
// find the connection from the flow key
TcpReassemblyConnMgrIter iter2 = connMgr->find(flowKeyToCloseFiles);
if (iter2 != connMgr->end())
auto flow2 = connMgr->find(flowKeyToCloseFiles);
if (flow2 != connMgr->end())
{
// close files on both sides (if they're open)
for (int index = 0; index < 2; index++)
{
if (iter2->second.fileStreams[index] != nullptr)
if (flow2->second.fileStreams[index] != nullptr)
{
// close the file
GlobalConfig::getInstance().closeFileSteam(iter2->second.fileStreams[index]);
iter2->second.fileStreams[index] = nullptr;
GlobalConfig::getInstance().closeFileSteam(flow2->second.fileStreams[index]);
flow2->second.fileStreams[index] = nullptr;

// set the reopen flag to true to indicate that next time this file will be opened it will be opened in append mode (and not overwrite mode)
iter2->second.reopenFileStreams[index] = true;
flow2->second.reopenFileStreams[index] = true;
}
}
}
Expand All @@ -397,25 +395,25 @@ static void tcpReassemblyMsgReadyCallback(int8_t sideIndex, const pcpp::TcpStrea
std::string fileName = GlobalConfig::getInstance().getFileName(tcpData.getConnectionData(), sideIndex, GlobalConfig::getInstance().separateSides) + ".txt";

// open the file in overwrite mode (if this is the first time the file is opened) or in append mode (if it was already opened before)
iter->second.fileStreams[side] = GlobalConfig::getInstance().openFileStream(fileName, iter->second.reopenFileStreams[side]);
flow->second.fileStreams[side] = GlobalConfig::getInstance().openFileStream(fileName, flow->second.reopenFileStreams[side]);
}

// if this messages comes on a different side than previous message seen on this connection
if (sideIndex != iter->second.curSide)
if (sideIndex != flow->second.curSide)
{
// count number of message in each side
iter->second.numOfMessagesFromSide[sideIndex]++;
flow->second.numOfMessagesFromSide[sideIndex]++;

// set side index as the current active side
iter->second.curSide = sideIndex;
flow->second.curSide = sideIndex;
}

// count number of packets and bytes in each side of the connection
iter->second.numOfDataPackets[sideIndex]++;
iter->second.bytesFromSide[sideIndex] += (int)tcpData.getDataLength();
flow->second.numOfDataPackets[sideIndex]++;
flow->second.bytesFromSide[sideIndex] += (int)tcpData.getDataLength();

// write the new data to the file
iter->second.fileStreams[side]->write((char*)tcpData.getData(), tcpData.getDataLength());
flow->second.fileStreams[side]->write((char*)tcpData.getData(), tcpData.getDataLength());
}


Expand All @@ -425,13 +423,13 @@ static void tcpReassemblyMsgReadyCallback(int8_t sideIndex, const pcpp::TcpStrea
static void tcpReassemblyConnectionStartCallback(const pcpp::ConnectionData& connectionData, void* userCookie)
{
// get a pointer to the connection manager
TcpReassemblyConnMgr* connMgr = (TcpReassemblyConnMgr*)userCookie;
auto connMgr = (TcpReassemblyConnMgr*)userCookie;

// look for the connection in the connection manager
TcpReassemblyConnMgrIter iter = connMgr->find(connectionData.flowKey);
auto connectionMngr = connMgr->find(connectionData.flowKey);

// assuming it's a new connection
if (iter == connMgr->end())
if (connectionMngr == connMgr->end())
{
// add it to the connection manager
connMgr->insert(std::make_pair(connectionData.flowKey, TcpReassemblyData()));
Expand All @@ -446,35 +444,35 @@ static void tcpReassemblyConnectionStartCallback(const pcpp::ConnectionData& con
static void tcpReassemblyConnectionEndCallback(const pcpp::ConnectionData& connectionData, pcpp::TcpReassembly::ConnectionEndReason reason, void* userCookie)
{
// get a pointer to the connection manager
TcpReassemblyConnMgr* connMgr = (TcpReassemblyConnMgr*)userCookie;
auto connMgr = (TcpReassemblyConnMgr*)userCookie;

// find the connection in the connection manager by the flow key
TcpReassemblyConnMgrIter iter = connMgr->find(connectionData.flowKey);
auto connection = connMgr->find(connectionData.flowKey);

// connection wasn't found - shouldn't get here
if (iter == connMgr->end())
if (connection == connMgr->end())
return;

// write a metadata file if required by the user
if (GlobalConfig::getInstance().writeMetadata)
{
std::string fileName = GlobalConfig::getInstance().getFileName(connectionData, 0, false) + "-metadata.txt";
std::ofstream metadataFile(fileName.c_str());
metadataFile << "Number of data packets in side 0: " << iter->second.numOfDataPackets[0] << std::endl;
metadataFile << "Number of data packets in side 1: " << iter->second.numOfDataPackets[1] << std::endl;
metadataFile << "Total number of data packets: " << (iter->second.numOfDataPackets[0] + iter->second.numOfDataPackets[1]) << std::endl;
metadataFile << "Number of data packets in side 0: " << connection->second.numOfDataPackets[0] << std::endl;
metadataFile << "Number of data packets in side 1: " << connection->second.numOfDataPackets[1] << std::endl;
metadataFile << "Total number of data packets: " << (connection->second.numOfDataPackets[0] + connection->second.numOfDataPackets[1]) << std::endl;
metadataFile << std::endl;
metadataFile << "Number of bytes in side 0: " << iter->second.bytesFromSide[0] << std::endl;
metadataFile << "Number of bytes in side 1: " << iter->second.bytesFromSide[1] << std::endl;
metadataFile << "Total number of bytes: " << (iter->second.bytesFromSide[0] + iter->second.bytesFromSide[1]) << std::endl;
metadataFile << "Number of bytes in side 0: " << connection->second.bytesFromSide[0] << std::endl;
metadataFile << "Number of bytes in side 1: " << connection->second.bytesFromSide[1] << std::endl;
metadataFile << "Total number of bytes: " << (connection->second.bytesFromSide[0] + connection->second.bytesFromSide[1]) << std::endl;
metadataFile << std::endl;
metadataFile << "Number of messages in side 0: " << iter->second.numOfMessagesFromSide[0] << std::endl;
metadataFile << "Number of messages in side 1: " << iter->second.numOfMessagesFromSide[1] << std::endl;
metadataFile << "Number of messages in side 0: " << connection->second.numOfMessagesFromSide[0] << std::endl;
metadataFile << "Number of messages in side 1: " << connection->second.numOfMessagesFromSide[1] << std::endl;
metadataFile.close();
}

// remove the connection from the connection manager
connMgr->erase(iter);
connMgr->erase(connection);
}


Expand All @@ -494,7 +492,7 @@ static void onApplicationInterrupted(void* cookie)
static void onPacketArrives(pcpp::RawPacket* packet, pcpp::PcapLiveDevice* dev, void* tcpReassemblyCookie)
{
// get a pointer to the TCP reassembly instance and feed the packet arrived to it
pcpp::TcpReassembly* tcpReassembly = (pcpp::TcpReassembly*)tcpReassemblyCookie;
auto tcpReassembly = (pcpp::TcpReassembly*)tcpReassemblyCookie;
tcpReassembly->reassemblePacket(packet);
}

Expand Down Expand Up @@ -598,7 +596,7 @@ int main(int argc, char* argv[])
size_t maxOpenFiles = DEFAULT_MAX_NUMBER_OF_CONCURRENT_OPEN_FILES;

int optionIndex = 0;
int opt = 0;
int opt;

while((opt = getopt_long(argc, argv, "i:r:o:e:f:mcsvhl", TcpAssemblyOptions, &optionIndex)) != -1)
{
Expand Down Expand Up @@ -633,7 +631,6 @@ int main(int argc, char* argv[])
case 'h':
printUsage();
exit(0);
break;
case 'v':
printAppVersion();
break;
Expand Down

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