source: trunk/ETSI-Testsuites/ETSI_auto_IOT/adapter/src/Capture/PCAPCapture.cpp @ 27

/**
 * @file PCAPCapture.cpp
 * @author Tomas Urban
 * @version 0.4
 * @date 23/07/2009
 */
#include "PCAPCapture.h"
#include <boost/thread/thread.hpp>
#include <boost/tokenizer.hpp>
#include "Logger/Logger.h"

PCAPCapture::PCAPCapture() :
        m_fp(NULL),
        m_nHandleCount(0),
        m_bRunning(false),
        m_dumpFiles(0),
        m_threadRunning(0)
{
}

PCAPCapture::~PCAPCapture() 
{
        CloseDevice();  
}

pcap_t * PCAPCapture::OpenPcapSource(const std::string sSource)
{
        char errbuf[PCAP_ERRBUF_SIZE];
        return pcap_open(sSource.c_str(), SNAP_LEN, PCAP_OPENFLAG_PROMISCUOUS,
                1000, NULL, errbuf);
}

void PCAPCapture::CloseDevice()
{
        if (m_fp != NULL)
        {
                StopCapture();
                CloseCaptureFile();
                for (int i = 0; i < m_nHandleCount; i++)
                        pcap_close(m_fp[i]);
                delete m_fp;
                m_fp = NULL;
                m_threadRunning = NULL;
                m_nHandleCount = 0;
        }
}
void PCAPCapture::SetPcapHandles(pcap_t ** srcBuf, int nLen)
{
        CloseDevice();
        m_fp = new pcap_t*[nLen];
        m_nHandleCount = nLen;
        memcpy(m_fp, srcBuf, nLen * sizeof(pcap_t*));
        m_threadRunning = new bool[nLen];
        memset(m_threadRunning, 0, nLen * sizeof(bool));
}

void PCAPCapture::DispatcherHandler(u_char *temp1, 
                        const struct pcap_pkthdr *header, const u_char *pkt_data)
{       
        PCAPCapture::CapturingThread * pThread = reinterpret_cast<PCAPCapture::CapturingThread*>(temp1);
        PCAPCapture * pObj = pThread->m_pCapture;
        int nIndex = pThread->m_nHandleIndex;
        if (pObj->m_dumpFiles)
        {
                boost::mutex::scoped_lock lock(pObj->m_mutex);
                pcap_dump(reinterpret_cast <u_char*>(pObj->m_dumpFiles[nIndex]), header, pkt_data);
        }
        CapturedData cd;
        cd.SetData(header->caplen, reinterpret_cast <const char*> (pkt_data));
        cd.SetTimestamp(header->ts);
        if (pObj->m_fp)
                pObj->ProcessCapturedData(&cd);
}

PCAPCapture::CapturingThread::CapturingThread(PCAPCapture * pCapture, int nHandleIndex) :
        m_pCapture(pCapture),
        m_nHandleIndex(nHandleIndex)
{
}

void PCAPCapture::CapturingThread::operator()()
{
        std::string s = "Packet capture started";
        std::string s2 = "";
        if (m_pCapture->m_nHandleCount > 1)
        {
                s2 = " (source #";
                s2 += boost::lexical_cast<std::string>(m_nHandleIndex + 1);
                s2 += ")";
                s += s2;
        }
        Logger::Instance().LogDebug(s);

        pcap_loop(m_pCapture->m_fp[m_nHandleIndex], 0, PCAPCapture::DispatcherHandler, 
                reinterpret_cast <u_char*> (this));

        s = "Packet capture ended";
        s += s2;
        Logger::Instance().LogDebug(s);
        {
                boost::mutex::scoped_lock(m_pCapture->m_mutex);
                m_pCapture->m_threadRunning[m_nHandleIndex] = false;
                if (m_pCapture->m_bRunning)
                        m_pCapture->m_threadClosed.notify_one();
        }
}

bool PCAPCapture::StartCapture()
{
        if (m_bRunning)
                return true;
        m_bRunning = true;
        if (m_fp)               
        {
                for (int i = 0; i < m_nHandleCount; i++)
                {
                        m_threadRunning[i] = true;
                        boost::thread thread(CapturingThread(this, i));
                }
        }
        return true;
}

bool PCAPCapture::StopCapture()
{       
        if (!m_bRunning)
                return true;
        m_bRunning = false;
        if (m_fp)
        {
                for (int i = 0; i < m_nHandleCount; i++)
                {
                        boost::mutex::scoped_lock cond(m_mutex);
                        if (m_threadRunning[i])
                        {
                                pcap_breakloop(m_fp[i]);
                                m_threadClosed.wait(cond);
                        }
                }
        }
        return true;
}

bool PCAPCapture::SetFilter(const std::string sFilter)
{
        if (!m_fp)
        {
                Logger::Instance().LogWarning("Cannot apply filter; the capture device is not open");
                return false;
        }
        
        std::string sFormattedFilter = sFilter;

        // compile the filter           
        struct bpf_program fcode;
        std::string s = "Setting PCAP filter (";
        s += sFormattedFilter;
        s += ")...";
        Logger::Instance().LogDebug(s);
        bool bRes = true;
        for (int i = 0; i < m_nHandleCount; i++)
        {               
                if (m_nHandleCount > 1)
                {
                        s = "Applying filter to source #";
                        s += boost::lexical_cast<std::string>(i + 1);
                        s += "...";
                        Logger::Instance().LogDebug(s);
                }                               
                if (pcap_compile(m_fp[i], &fcode, sFormattedFilter.c_str(), 1, 0) < 0)
                {
                        Logger::Instance().LogError("Error compiling packet filter");
                        bRes = false;
                        continue;
                }
            
                //set the filter
                int nRes = pcap_setfilter(m_fp[i], &fcode);
                pcap_freecode(&fcode);
                if (nRes < 0)
                {
                        Logger::Instance().LogError("Error setting packet filter");
                        bRes = false;
                        continue;
                }               
                Logger::Instance().LogInfo("Filter applied successfully");
        }
        Logger::Instance().LogDebug("PCAP filter ready");
        return bRes;
}

void PCAPCapture::CloseCaptureFile()
{
        if (m_dumpFiles)
        {
                boost::mutex::scoped_lock lock(m_mutex);
                for (int i = 0; i < m_nHandleCount; i++)
                        pcap_dump_close(m_dumpFiles[i]);
                delete m_dumpFiles;
                m_dumpFiles = 0;
        }
}

bool PCAPCapture::InitCaptureFile(const std::string sFile)
{
        if (!m_nHandleCount)
                return false;
        CloseCaptureFile();
        bool bRes = true;
        if (sFile.length() > 0)
        {
                boost::mutex::scoped_lock lock(m_mutex);
                m_dumpFiles = new pcap_dumper_t * [m_nHandleCount];
                memset(m_dumpFiles, 0, sizeof(pcap_dumper_t*) * m_nHandleCount);

                std::string sName = sFile;
                std::string sExt = "";
                if (m_nHandleCount > 1)
                {
                        size_t nSize = sFile.find_last_of('.');
                        if (nSize < sFile.length())
                        {
                                sName = sFile.substr(0, nSize);
                                sExt = sFile.substr(nSize);
                        }
                }
                
                for (int i = 0; i < m_nHandleCount; i++)
                {
                        std::string sTmp = sFile;
                        if (m_nHandleCount > 1)
                        {
                                sTmp = sName;
                                sTmp += boost::lexical_cast<std::string>(i + 1);
                                sTmp += sExt;
                        }
                        m_dumpFiles[i] = pcap_dump_open(m_fp[i], sTmp.c_str());
                        if (!m_dumpFiles[i])
                        {
                                std::string s = "Failed to create dump file \"";
                                s += sTmp;
                                s += "\"";
                                Logger::Instance().LogError(s);
                                return false;
                        }
                }
                Logger::Instance().LogDebug("PCAP dump file successfully initialized");
        }
        else
                Logger::Instance().LogDebug("Dump file disabled");
        return true;;
}