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Retail products

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Traffic interception SDK

Control every TCP/IP network connection

• Route connections via proxy
• Redirect connections and modify the data
• Block connections and applications

Learn More

SSL interception SDK

View SSL in plaintext and modify it

• View the SSL stream decrypted in plaintext
• Redirect SSL connection and modify decrypted data
• Browser shows "SSL lock" without warnings

Learn More

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Documentation

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DNSAnswers.cpp Go to the documentation of this file. /* * Copyright (c) 2000-2003 Barak Weichselbaum <barak@komodia.com> * 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. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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. * * Contact info: * ------------- * * Site: http://www.komodia.com * Main contact: barak@komodia.com * For custom projects, * consulting, or other * paid services: sales@komodia.com */ #include "stdafx.h" #include "DNSAnswers.h" #include "ErrorHandlerMacros.h" #include "Array_ptr.h" #include "SpoofBase.h" #include "DNSParser.h" #ifdef _MEMORY_DEBUG #define new DEBUG_NEW #define malloc DEBUG_MALLOC static char THIS_FILE[] = __FILE__; #endif namespace KomodiaDNS { #define CDNSAnswers_Class "CDNSAnswers" CDNSAnswers::CDNSAnswers() : CErrorHandler(), m_pDNSQuery(NULL) { try { //Set our name SetName(CDNSAnswers_Class); } ERROR_HANDLER("CDNSAnswers") } CDNSAnswers::CDNSAnswers(const CDNSAnswers& rAnswers) : CErrorHandler(), m_pDNSQuery(NULL), m_aAnswers(rAnswers.m_aAnswers) { try { //Set our name SetName(CDNSAnswers_Class); //Do we have a query? if (rAnswers.m_pDNSQuery) //Copy it m_pDNSQuery=new CDNSQuery(*rAnswers.m_pDNSQuery); } ERROR_HANDLER("CDNSAnswers") } CDNSAnswers::~CDNSAnswers() { try { //Delete the query delete m_pDNSQuery; } ERROR_HANDLER("~CDNSAnswers") } const CDNSAnswer& CDNSAnswers::GetAnswer(unsigned short usIndex)const { return m_aAnswers[usIndex]; } int CDNSAnswers::Parse(const char *pBuffer, int iLength) { try { //Delete previous data UnInitialize(); if (iLength<=DnsHeaderHeaderLength) { //Report it ReportError("Parse","Buffer size too small!"); //Exit return 0; } //Start parsing the dude const char* pBackupBuffer=pBuffer; //Let's start with the answer memcpy(&m_aDNSHeader, pBackupBuffer, DnsHeaderHeaderLength); //Reverse the header ReverseHeader(); //Increase the buffer pBackupBuffer+=DnsHeaderHeaderLength; //OK now we can continue m_pDNSQuery=new CDNSQuery; //Get the number of data the query parsed ! unsigned short usParseLength; //Parse it usParseLength=m_pDNSQuery->Parse(pBackupBuffer, m_aDNSHeader.usQDCount); //Check for errors if (!usParseLength) { //Report it ReportError("Parse","Received zero length!"); //Exit return 0; } //Increase the buffer pBackupBuffer+=usParseLength; //Parse the rest of the headers return ParseAnswers(pBackupBuffer, pBuffer); } ERROR_HANDLER_RETURN("Parse",0) } void CDNSAnswers::UnInitialize() { try { //Delete the query delete m_pDNSQuery; m_pDNSQuery=NULL; //Clear the vector m_aAnswers.clear(); } ERROR_HANDLER("UnInitialize") } void CDNSAnswers::ReverseHeader() { try { //Everything is reversed, change it m_aDNSHeader.usANCount=htons(m_aDNSHeader.usANCount); m_aDNSHeader.usARCount=htons(m_aDNSHeader.usARCount); m_aDNSHeader.usID=htons(m_aDNSHeader.usID); m_aDNSHeader.usNSCount=htons(m_aDNSHeader.usNSCount); m_aDNSHeader.usQDCount=htons(m_aDNSHeader.usQDCount); } ERROR_HANDLER("ReverseHeader") } unsigned short CDNSAnswers::ParseAnswers(const char *pBuffer, const char* pOriginalBuffer) { try { //Let's start //Get number of answers int iAnswers; iAnswers=m_aDNSHeader.usARCount+ m_aDNSHeader.usANCount+ m_aDNSHeader.usNSCount; for (int iCount=0;iCount<iAnswers;++iCount) { //Our answer CDNSAnswer aAnswer; //Try to parse it unsigned short usParseSize; usParseSize=aAnswer.ParseBuffer(pBuffer, pOriginalBuffer); if (!usParseSize) { //Report it ReportError("ParseAnswers","Failed to parse answer!"); //Exit return 0; } //Set the answer type CDNSAnswer::DnsHeaderType aAnswerType; if (iCount<m_aDNSHeader.usANCount) aAnswerType=CDNSAnswer::dhAnswer; else if (iCount<m_aDNSHeader.usANCount+ m_aDNSHeader.usNSCount) aAnswerType=CDNSAnswer::dhAuthoritive; else aAnswerType=CDNSAnswer::dhAdditional; //Set it at the class aAnswer.SetAnswerType(aAnswerType); //Add it to the vector m_aAnswers.push_back(aAnswer); //Increase the buffer size pBuffer+=usParseSize; } //Done return pBuffer-pOriginalBuffer; } ERROR_HANDLER_RETURN("ParseAnswers",0) } unsigned long CDNSAnswers::GetAddress(unsigned short usIndex)const { try { if (!m_aDNSHeader.usARCount || !m_aDNSHeader.usANCount) { //Report it ReportError("GetAddress","No answers!"); //Exit return 0; } //Get to the actual answer unsigned short usPrior; usPrior=m_aDNSHeader.usANCount+ m_aDNSHeader.usNSCount; for (unsigned short usCounter=usIndex; usCounter<m_aDNSHeader.usARCount-usIndex; ++usCounter) if (m_aAnswers[usPrior+usCounter].GetResourceType()==CDNSQuery::A) { //Get the data std::string sData; sData=m_aAnswers[usPrior+usCounter].GetData(); //Convert it to long return atol(sData.c_str()); } //Nothing return 0; } ERROR_HANDLER_RETURN("GetAddress",0) } BOOL CDNSAnswers::IsResolved()const { return !(m_aDNSHeader.usOptions & DNS_SERVER_FAILURE); } unsigned short CDNSAnswers::GetDNSID() const { return m_aDNSHeader.usID; } unsigned long CDNSAnswers::GetAIPAnswer()const { try { //Do we have an answer ? if (!m_aDNSHeader.usANCount || m_aAnswers.empty()) return 0; //Get the answer const CDNSAnswer& rAnswer=m_aAnswers[0]; //Check what type is it ? if (rAnswer.GetResourceType()==CDNSQuery::A) { //Get the data std::string sData; sData=rAnswer.GetData(); //Convert it to long return atol(sData.c_str()); } else if (rAnswer.GetResourceType()==CDNSQuery::MX && m_aDNSHeader.usARCount) { //Look for the additional resources int iPos; iPos=m_aDNSHeader.usANCount+ m_aDNSHeader.usNSCount; //Our data std::string sData; sData=rAnswer.GetData(); //Loop them for (int iCount=0; iCount<m_aDNSHeader.usARCount; iCount++) { //Get the answer const CDNSAnswer& rARAnswer=m_aAnswers[iCount+iPos]; //Is it an A record? if (rARAnswer.GetResourceType()==CDNSQuery::A && rARAnswer.GetName()==sData) //This is us return atol(rARAnswer.GetData().c_str()); } //Not found return 0; } else return 0; } ERROR_HANDLER_RETURN("GetAIPAnswer",0) } CDNSAnswers::IPAnswersVector CDNSAnswers::GetAIPAnswers()const { //Empty vector static IPAnswersVector aEmptyVector; try { //Our vector IPAnswersVector aVector; //Do we have an answer ? if (!m_aDNSHeader.usANCount || m_aAnswers.empty()) return aVector; //Iterate the answers for (int iCount=0; iCount<m_aDNSHeader.usANCount; ++iCount) { //Get the answer const CDNSAnswer& rAnswer=m_aAnswers[iCount]; //Check what type is it ? if (rAnswer.GetResourceType()==CDNSQuery::A) { //Get the data std::string sData; sData=rAnswer.GetData(); //Convert it to long aVector.push_back(atol(sData.c_str())); } else if (rAnswer.GetResourceType()==CDNSQuery::MX && m_aDNSHeader.usARCount) { //Look for the additional resources int iPos; iPos=m_aDNSHeader.usANCount+ m_aDNSHeader.usNSCount; //Our data std::string sData; sData=rAnswer.GetData(); //Loop them for (int iCount=0; iCount<m_aDNSHeader.usARCount; iCount++) { //Get the answer const CDNSAnswer& rARAnswer=m_aAnswers[iCount+iPos]; //Is it an A record? (may have more then one A record per type) if (rARAnswer.GetResourceType()==CDNSQuery::A && rARAnswer.GetName()==sData) //This is us aVector.push_back(atol(rARAnswer.GetData().c_str())); } } } //Done return aVector; } ERROR_HANDLER_RETURN("GetAIPAnswers",aEmptyVector) } std::string CDNSAnswers::GetAnswer()const { try { //Do we have an answer ? if (!m_aDNSHeader.usANCount || m_aAnswers.empty()) return ""; //Get the answer const CDNSAnswer& rAnswer=m_aAnswers[0]; //Check what type is it ? if (rAnswer.GetResourceType()==CDNSQuery::PTR || rAnswer.GetResourceType()==CDNSQuery::MX) { //Get the data std::string sData; sData=rAnswer.GetData(); //Convert it to long return sData; } else if (rAnswer.GetResourceType()==CDNSQuery::A) { //Get the data std::string sData; sData=rAnswer.GetData(); //Convert to DWORD DWORD dwIP; dwIP=atof(sData.c_str()); //Convert to string return CSpoofBase::LongToStdString(dwIP); } else return ""; } ERROR_HANDLER_RETURN("GetAnswer","") } CDNSAnswers::StringAnswersVector CDNSAnswers::GetAnswers()const { //Empty vector static StringAnswersVector aEmptyVector; try { //Our vector StringAnswersVector aVector; //Do we have an answer ? if (!m_aDNSHeader.usANCount || m_aAnswers.empty()) return aEmptyVector; //Iterate the answers for (int iCount=0; iCount<m_aDNSHeader.usANCount; ++iCount) { //Get the answer const CDNSAnswer& rAnswer=m_aAnswers[iCount]; //Check what type is it ? if (rAnswer.GetResourceType()==CDNSQuery::PTR || rAnswer.GetResourceType()==CDNSQuery::MX) { //Get the data std::string sData; sData=rAnswer.GetData(); //Add it aVector.push_back(sData); } else if (rAnswer.GetResourceType()==CDNSQuery::A) { //Get the data std::string sData; sData=rAnswer.GetData(); //Convert to DWORD DWORD dwIP; dwIP=atof(sData.c_str()); //Convert to string //Add it aVector.push_back(CSpoofBase::LongToStdString(dwIP)); } } //Done return aVector; } ERROR_HANDLER_RETURN("GetAnswers",aEmptyVector) } const CDNSQuery* CDNSAnswers::GetQuery()const { return m_pDNSQuery; } std::string CDNSAnswers::GetAnswerParsed(BOOL bWindowsLines, BOOL bBrief, BOOL bExtraLine)const { try { //Line terminator //End of line char aEndOfLine[3]; //Which is it if (bWindowsLines) { aEndOfLine[0]=13; aEndOfLine[1]=10; aEndOfLine[2]=0; } else { aEndOfLine[0]='\n'; aEndOfLine[1]=0; } //Our string std::string sAnswer; //Iterate answers for (int iCount=0; iCount<m_aAnswers.size(); iCount++) { //What are we if (iCount<m_aDNSHeader.usANCount && !iCount) { //Answer sAnswer+="Non-authoritative answer:"; sAnswer+=aEndOfLine; } else if ((iCount<m_aDNSHeader.usANCount+ m_aDNSHeader.usNSCount) && iCount==m_aDNSHeader.usANCount) { //Authority servers sAnswer+=aEndOfLine; sAnswer+="Authoritive servers:"; sAnswer+=aEndOfLine; } else if (iCount==m_aDNSHeader.usANCount+ m_aDNSHeader.usNSCount) { //Additional records sAnswer+=aEndOfLine; sAnswer+="Additional records:"; sAnswer+=aEndOfLine; } //Add the answer sAnswer+=m_aAnswers[iCount].GetAnswerParsed(bWindowsLines, bBrief); sAnswer+=aEndOfLine; } //Do we need another line? if (bExtraLine) sAnswer+=aEndOfLine; //Done return sAnswer; } ERROR_HANDLER_RETURN("GetAnswerParsed","") } BOOL CDNSAnswers::IsReverseAnswer()const { return IsResolved() && m_pDNSQuery->GetFirstQueryType()==CDNSQuery::PTR; } //of namespace }

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