diff options
Diffstat (limited to 'mDNSResponder/mDNSMacOSX/BonjourTop/source/DNSFrame.cpp')
| -rw-r--r-- | mDNSResponder/mDNSMacOSX/BonjourTop/source/DNSFrame.cpp | 384 |
1 files changed, 384 insertions, 0 deletions
diff --git a/mDNSResponder/mDNSMacOSX/BonjourTop/source/DNSFrame.cpp b/mDNSResponder/mDNSMacOSX/BonjourTop/source/DNSFrame.cpp new file mode 100644 index 00000000..1e8586a0 --- /dev/null +++ b/mDNSResponder/mDNSMacOSX/BonjourTop/source/DNSFrame.cpp @@ -0,0 +1,384 @@ +// +// DNSFrame.cpp +// TestTB +// +// Created by Terrin Eager on 9/26/12. +// +// + +#include "DNSFrame.h" + +#define DNS_LABEL_MAX_LENGTH 63 +#define DNS_NAME_MAX_LENGTH 255 + +void CDNSRecord::GetDnsRecordName(BJString& ReturnString,int nLabelToSkip,int nMaxLabel) +{ + GetDnsRecordNameFromBuffer(m_pStartofRec, ReturnString, nLabelToSkip, nMaxLabel); +} + +void CDNSRecord::GetDnsRecordNameFromBuffer(BJ_UINT8* pBuffer,BJString& ReturnString,int nLabelToSkip,int nMaxLabel) +{ + BJ_UINT8* pNameBuffer = NULL; + int nOffset = 0; + // char* pTemp = pReturnBuffer; + int nCharCount = 0; + int nSkippedLabels = 0; + int nLabelProcessed = 0; + ReturnString.Set(NULL,255); + + if (ReturnString.GetBuffer() == NULL) + return; + + pNameBuffer = pBuffer; + if (pNameBuffer == NULL) + { + return; + } + + while (ReturnString.GetBufferLength() < 1024) + { + nCharCount = *pNameBuffer++; + if (nCharCount == 0) + break; + + if ((nCharCount&(DNS_NAME_OFFSET_MASK)) == DNS_NAME_OFFSET_MASK) + { + nOffset = *pNameBuffer++; + nOffset |= (nCharCount&(~DNS_NAME_OFFSET_MASK)) << 8; + pNameBuffer = m_pDNSFrame->GetBuffer() + nOffset; + continue; + } + + if (nCharCount > DNS_LABEL_MAX_LENGTH) + { + printf("label too long %d\n",nCharCount); + break; + } + + if (ReturnString.GetLength() + nCharCount + 1 > DNS_NAME_MAX_LENGTH) // + 1 is for the '.' added later on + { + printf("Name exceeded limit allowed for DNS: %d\n", ReturnString.GetLength() + nCharCount + 1); + break; + } + + if (nLabelToSkip > nSkippedLabels) + { + nSkippedLabels++; + pNameBuffer += nCharCount; + continue; + } + ReturnString.Append((char*)pNameBuffer, nCharCount); + pNameBuffer+= nCharCount; + nLabelProcessed++; + + if (nLabelProcessed >= nMaxLabel) + return; + + ReturnString += "."; + } +} + + + + +CDNSFrame::CDNSFrame() +{ + + for(int nIndex=0; nIndex < MAX_DNS_RECORDS_PER_FRAME; nIndex++) + m_dnsItems[nIndex].m_pDNSFrame = this; + +} + +CDNSRecord* CDNSFrame::GetDnsRecord(int nIndex) +{ + if (nIndex > m_nMaxItems) + return NULL; + return &m_dnsItems[nIndex]; +} + +bool CDNSFrame::ParseDNSFrame(BJ_UINT8* pBuffer,BJ_INT32 nLength, BJ_UINT64 frameTime) +{ + if (pBuffer == NULL) + return false; + + int nIndex = 0; + + m_Servicev4Address.Empty(); + m_Servicev6Address.Empty(); + + m_pStartBuffer = pBuffer; + m_nFrameLen = (BJ_UINT32) nLength; + + m_pCurrentBuffer = m_pStartBuffer; + m_pEndBuffer = m_pStartBuffer + m_nFrameLen; + m_Time = frameTime; + + m_nId = PF_GET_UINT16(m_pStartBuffer,0); + m_nFlags = PF_GET_UINT16(m_pStartBuffer,2); + m_nQuestionCount = PF_GET_UINT16(m_pStartBuffer,4); + m_nAnswersCount = PF_GET_UINT16(m_pStartBuffer,6); + m_NSCOUNT = PF_GET_UINT16(m_pStartBuffer,8); + m_ARCOUNT = PF_GET_UINT16(m_pStartBuffer,10); + + m_nMaxItems = 0; + + + + // printf("FrameNum= %d,nQuestionCount= %d nAnswersCount= %d NSCOUNT= %d ARCOUNT= %d\n",nFrameCount++,m_nQuestionCount, m_nAnswersCount,m_NSCOUNT, m_ARCOUNT); + + m_pCurrentBuffer = m_pStartBuffer + 12; + + + for (nIndex =0; nIndex < m_nQuestionCount;nIndex++) + { + // printf("FramePosition= %ld ",m_pCurrentBuffer); + ParseDnsRecord(CDNSRecord::Question); + + } + for (nIndex =0; nIndex < m_nAnswersCount;nIndex++) + { + // printf("FramePosition= %ld ",m_pCurrentBuffer); + ParseDnsRecord(CDNSRecord::Answer); + } + for (nIndex =0; nIndex < m_NSCOUNT;nIndex++) + { + // printf("FramePosition= %ld ",m_pCurrentBuffer); + ParseDnsRecord(CDNSRecord::Answer); + } + for (nIndex =0; nIndex < m_ARCOUNT;nIndex++) + { + // printf("FramePosition= %ld ",m_pCurrentBuffer); + ParseDnsRecord(CDNSRecord::Answer); + CDNSRecord* pRecord = &m_dnsItems[m_nMaxItems-1]; + if (pRecord->m_RecType == DNS_TYPE_AAAA && m_Servicev6Address.IsEmpty()) + { + m_Servicev6Address.Setv6Raw(pRecord->GetStartofRdata()); + } + if (pRecord->m_RecType == DNS_TYPE_A && m_Servicev4Address.IsEmpty()) + { + m_Servicev4Address.Setv4Raw(pRecord->GetStartofRdata()); + } + } + // + /// for (dnsItemsIndex =0; dnsItemsIndex < m_nQuestionCount+m_nAnswersCount;dnsItemsIndex++) + /// { + /// printf("Name = %s\n", GetDnsRecordName(&Frame,dnsItemsIndex,tempBuffer,sizeof(tempBuffer))); + // } + return true; +} + +BJ_BOOL CDNSFrame::ParseDnsRecord(CDNSRecord::dnsItemType eItemType) +{ + unsigned char nCharCount = 0; + BJ_UINT8* pTemp = m_pCurrentBuffer; + CDNSRecord* pRecord = &m_dnsItems[m_nMaxItems++]; + + //temp + BJ_UINT16 nRdataLen = 0; + BJ_UINT16 nRdataLen2 = 0; + + if (pTemp > m_pEndBuffer) + { + printf("Error in ParseDnsRecord pBuffer > pEndBuffer\n"); + pRecord->m_pStartofRec = NULL; + pRecord->m_nNameLength = 0; + return false; + } + + + pRecord->m_pStartofRec = pTemp; + pRecord->m_nNameLength = 0; + pRecord->m_nRdataLen = 0; + + + // Skip over Name; + while (pTemp < m_pEndBuffer) + { + nCharCount = *pTemp; + pTemp++; + + if (nCharCount == 0) + break; + + if ((nCharCount&(DNS_NAME_OFFSET_MASK)) == DNS_NAME_OFFSET_MASK) + { // offset string + pTemp++; + break; + } + + if (nCharCount > DNS_LABEL_MAX_LENGTH) + { + printf("%d. label too long %d\n",m_nMaxItems-1,nCharCount); + } + + if (pTemp + nCharCount < m_pEndBuffer) + pTemp += nCharCount; + else + pTemp = m_pEndBuffer; + } + + pRecord->m_nNameLength = (BJ_UINT32)(pTemp - pRecord->m_pStartofRec); + + if (eItemType == CDNSRecord::Question) + { + pRecord->m_RecType = PF_GET_UINT16(pTemp,0); + pRecord->m_RecClass = PF_GET_UINT16(pTemp,2); + pRecord->m_nTTL = PF_GET_UINT16(pTemp,4); + + // printf("Namelen=%u, Type=%u, class=%u, TTL=%u, RDLength=%u\n", m_dnsItems[ndnsIndex].nNameLength,nType,nClass,nTTL,nRdataLen); + + pTemp += 4; + } + else + { + + pRecord->m_RecType = PF_GET_UINT16(pTemp,0); + pRecord->m_RecClass = PF_GET_UINT16(pTemp,2); + + pRecord->m_nTTL = PF_GET_UINT32(pTemp,4); + pRecord->m_nRdataLen = PF_GET_UINT16(pTemp,8); + if (nRdataLen > 1024*10) + { + printf("large Rdata ??"); + nRdataLen2 = (pTemp[8] << 8) | pTemp[9]; + + } + // printf("Namelen=%u, Type=%u, class=%u, TTL=%u, RDLength=%u\n", m_dnsItems[ndnsIndex].nNameLength,m_dnsItems[ndnsIndex].RecType,nClass,nTTL,m_dnsItems[ndnsIndex].nRdataLen); + pTemp += 10 + pRecord->m_nRdataLen; + } + + m_pCurrentBuffer = pTemp; + + return true; +} + +BJ_BOOL CDNSFrame::IsQueryFrame() +{ + return !(m_nFlags&0x8000); +} + +#define UNICAST_RESPONDS_REQUESTED 0x8000 +BJ_BOOL CDNSFrame::IsWakeFrame() +{ + + for (int i=0; i < m_nQuestionCount; i++) + { + if (m_dnsItems[i].m_RecType == DNS_TYPE_PTR && m_dnsItems[i].m_RecClass & UNICAST_RESPONDS_REQUESTED) + return true; + } + + return false; +} +#define DNS_HEADER_TRUNCATEED 0x0200 +BJ_BOOL CDNSFrame::IsTruncatedFrame() +{ + return (m_nFlags&DNS_HEADER_TRUNCATEED); +} + + +BJ_BOOL CDNSFrame::HasOnlyService(BJString sName, BJ_INT16 nRecType) +{ + /* if (IsQueryFrame()) + { + for (int i=0; i < m_nQuestionCount; i++) + { + CBJString sRecordName; + m_dnsItems[i].GetDnsRecordName(sRecordName, 0); + if (m_dnsItems[i].m_RecType != nRecType && nRecType != -1) + return false; + + if (!sRecordName.Contains(sName.GetBuffer())) + return false; + } + } + else*/ + { + for (int i=0; i < m_nQuestionCount+m_nAnswersCount; i++) + { + BJString sRecordName; + m_dnsItems[i].GetDnsRecordName(sRecordName, 0,99); + if (m_dnsItems[i].m_RecType != nRecType && nRecType != -1) + return false; + + if (!sRecordName.Contains(sName.GetBuffer())) + return false; + } + + + } + + + return true; +} + +CDNSRecord* CDNSFrame::FindAdditionRecord(BJString& sName,BJ_INT16 nRecType) +{ + for (int i = 0; i < m_nMaxItems; i++) + { + if (m_dnsItems[i].m_RecType != nRecType && nRecType != -1) + continue; + BJString sRecordName; + m_dnsItems[i].GetDnsRecordName(sRecordName, 0,99); + if (sRecordName == sName) + return &m_dnsItems[i]; + } + return NULL; +} + +void CDNSFrame::SetAddress(BJIPAddr *pSourceIPAddress,BJMACAddr *pSourceMACAddress) +{ + m_SourceIPAddress = *pSourceIPAddress; + m_SourceMACAddress = *pSourceMACAddress; + + +} + + +bool CDNSFrame::GetTracingInfo(BJ_UINT8 &platform, BJ_UINT32 &version, BJMACAddr &) +{ + // Find OPT record + for (int i = m_nQuestionCount + m_nAnswersCount + m_NSCOUNT; i < m_nMaxItems; i++) + { + if (m_dnsItems[i].m_RecType == DNS_TYPE_OPT) + { + BJ_UINT8* rdata = m_dnsItems[i].GetStartofRdata(); + + BJ_UINT8* rdataEnd = rdata + m_dnsItems[i].m_nRdataLen; + + while (rdata < rdataEnd) + { + BJ_UINT16 type = PF_GET_UINT16(rdata,0); + BJ_UINT16 len = PF_GET_UINT16(rdata,2); + + if (type == DNS_EDNS0_TRACE) + { + platform = PF_GET_UINT8(rdata,4); + if (len == 3) // EDNS field of length 3 <rdar://15101783> + { + version = static_cast<BJ_UINT32>(PF_GET_UINT16(rdata,5)); + } + else if (len == 5) // EDNS field of length 5 <rdar://15235603> + { + version = static_cast<BJ_UINT32>(PF_GET_UINT32(rdata, 5)); + } + else + { + return false; + } + return true; + } + + + rdata += sizeof(BJ_UINT16)*2 + len; + } + + } + } + return false; + +} + + + + + |