// NULL name will always match
static DNSRR* DNSFindRR(DNSDG * pDNSDG, void * pRRCur, uint32_t rrr, uint16_t type, uint16_t _class, uint8_t * pName, uint8_t * pEnd)
{
uint8_t * pRR = DNSSkipToRRSection(pDNSDG, rrr, pEnd);
uint32_t cRR = ((uint16_t *) &pDNSDG->dnsHdr.QDCOUNT)[rrr-DNSRRQD];
uint32_t cbDNSRR = (rrr == DNSRRQD) ? sizeof(DNSQRR) : sizeof(DNSRR);
uint32_t i = 0;
// if we have indexed in
for(i=0; i<cRR && pRR < pEnd; i++)
{
DNSRR * pDNSRR = (DNSRR *) DNSSkipName(pRR, pEnd);
// compare the names
if( pRR >= (uint8_t *) pRRCur &&
pDNSRR->TYPE == type &&
pDNSRR->CLASS == _class &&
(pName == NULL || DNSCompareRRName((uint8_t *) pDNSDG, pName, pRR, pEnd)))
{
// we found a matching CName, so lets use the new CName and see if we find another CName
return(pDNSRR);
}
pRR = ((uint8_t *) pDNSRR) + pDNSRR->RDLENGTH + cbDNSRR;
}
return(NULL);
}
static DNSRR * DNSFindNSARR(DNSDG * pDNSDG, uint8_t * pName, uint8_t * pEnd, uint16_t dnsType)
{
DNSRR * pDNSRRNS = NULL;
DNSRR * pDNSRRA = NULL;
uint32_t i = 0;
uint32_t cBestMatch = 0;
DNSRR * pDNSRRABest = NULL;
uint8_t * pRR = DNSSkipToRRSection(pDNSDG, DNSRRNS, pEnd);
uint16_t rgLL[DNScLL];
uint32_t crgLL = DNSGetNameLabelList((uint8_t *) pDNSDG, pName, pEnd, 0, rgLL, DNScLL);
if(crgLL == 0)
{
return(NULL);
}
// now walk all of the name servers looking for the best match
for(i=0; i < pDNSDG->dnsHdr.NSCOUNT && ((uint8_t *) pDNSDG) <= pRR && pRR < pEnd; i++)
{
uint32_t cLabelMatches = 0;
pDNSRRNS = (DNSRR *) DNSSkipName(pRR, pEnd);
// see if this is a NS and that there is a dnsType in Additional records
if(pDNSRRNS != NULL && pDNSRRNS->TYPE == DNSTYPENS && (pDNSRRA = DNSFindRR(pDNSDG, NULL, DNSRRAR, dnsType, DNSCLASSIN, pDNSRRNS->RDATA, pEnd)) != NULL)
{
// now lets see how well this name matches to what we are looking for
cLabelMatches = DNSCompareLabelListAndName((uint8_t *) pDNSDG, pRR, pEnd, 0, rgLL, crgLL);
if(cLabelMatches > cBestMatch || pDNSRRABest == NULL)
{
pDNSRRABest = pDNSRRA;
}
}
pRR = ((uint8_t *) pDNSRRNS) + sizeof(DNSRR) + pDNSRRNS->RDLENGTH;
}
return(pDNSRRABest);
}
return(NULL);
}
// skip up to the record in question
for(i=0; i<cRRSkip && pRR < pEnd; i++)
{
pRR = DNSSkipRRecord(pRR, (i < pDNSDG->dnsHdr.QDCOUNT), pEnd);
}
return(pRR);
}
// NULL name will always match
static DNSRR * DNSFindRR(DNSDG * pDNSDG, void * pRRCur, uint32_t rrr, uint16_t type, uint16_t class, uint8_t * pName, uint8_t * pEnd)
{
uint8_t * pRR = DNSSkipToRRSection(pDNSDG, rrr, pEnd);
uint32_t cRR = ((uint16_t *) &pDNSDG->dnsHdr.QDCOUNT)[rrr-DNSRRQD];
uint32_t cbDNSRR = (rrr == DNSRRQD) ? sizeof(DNSQRR) : sizeof(DNSRR);
int i = 0;
// if we have indexed in
for(i=0; i<cRR && pRR < pEnd; i++)
{
DNSRR * pDNSRR = (DNSRR *) DNSSkipName(pRR, pEnd);
// compare the names
if( pRR >= (uint8_t *) pRRCur &&
pDNSRR->TYPE == type &&
pDNSRR->CLASS == class &&
(pName == NULL || DNSCompareRRName((uint8_t *) pDNSDG, pName, pRR, pEnd)))
{
