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windows-nt/Source/XPSP1/NT/ds/dns/dnsapi/query.c
CryptoAlgo Inc b3cac27891 Add source files
2020-09-26 16:20:57 +08:00

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/*++
Copyright (c) 1997-2001 Microsoft Corporation
Module Name:
query.c
Abstract:
Domain Name System (DNS) API
Query routines.
Author:
Jim Gilroy (jamesg) January, 1997
Revision History:
--*/
#include "local.h"
//
// TTL for answering IP string queries
// (use a week)
//
#define IPSTRING_RECORD_TTL (604800)
//
// Max number of server's we'll ever bother to extract from packet
// (much more and you're out of UDP packet space anyway)
//
#define MAX_NAME_SERVER_COUNT (20)
//
// Query utilities
//
// DCR: move to library packet stuff
//
BOOL
IsEmptyDnsResponse(
IN PDNS_RECORD pRecordList
)
/*++
Routine Description:
Check for no-answer response.
Arguments:
pRecordList -- record list to check
Return Value:
TRUE if no-answers
FALSE if answers
--*/
{
PDNS_RECORD prr = pRecordList;
BOOL fempty = TRUE;
while ( prr )
{
if ( prr->Flags.S.Section == DNSREC_ANSWER )
{
fempty = FALSE;
break;
}
prr = prr->pNext;
}
return fempty;
}
BOOL
IsEmptyDnsResponseFromResolver(
IN PDNS_RECORD pRecordList
)
/*++
Routine Description:
Check for no-answer response.
Arguments:
pRecordList -- record list to check
Return Value:
TRUE if no-answers
FALSE if answers
--*/
{
PDNS_RECORD prr = pRecordList;
BOOL fempty = TRUE;
//
// resolver sends every thing back as ANSWER section
// or section==0 for host file
//
//
// DCR: this is lame because the query interface to the
// resolver is lame
//
while ( prr )
{
if ( prr->Flags.S.Section == DNSREC_ANSWER ||
prr->Flags.S.Section == 0 )
{
fempty = FALSE;
break;
}
prr = prr->pNext;
}
return fempty;
}
VOID
FixupNameOwnerPointers(
IN OUT PDNS_RECORD pRecord
)
/*++
Routine Description:
None.
Arguments:
None.
Return Value:
None.
--*/
{
PDNS_RECORD prr = pRecord;
PTSTR pname = pRecord->pName;
DNSDBG( TRACE, ( "FixupNameOwnerPointers()\n" ));
while ( prr )
{
if ( prr->pName == NULL )
{
prr->pName = pname;
}
else
{
pname = prr->pName;
}
prr = prr->pNext;
}
}
BOOL
IsCacheableNameError(
IN PDNS_NETINFO pNetInfo
)
/*++
Routine Description:
Determine if name error is cacheable.
To this is essentially a check that DNS received results on
all networks.
Arguments:
pNetInfo -- pointer to network info used in query
Return Value:
TRUE if name error cacheable.
FALSE otherwise (some network did not respond)
--*/
{
DWORD iter;
PDNS_ADAPTER padapter;
DNSDBG( TRACE, ( "IsCacheableNameError()\n" ));
if ( !pNetInfo )
{
ASSERT( FALSE );
return TRUE;
}
//
// check each adapter
// - any that are capable of responding (have DNS servers)
// MUST have responded in order for response to be
// cacheable
//
// DCR: return flags DCR
// - adapter queried flag
// - got response flag (valid response flag?)
// - explict negative answer flag
//
// DCR: cachable negative should come back directly from query
// perhaps in netinfo as flag -- "negative on all adapters"
//
for ( iter = 0; iter < pNetInfo->AdapterCount; iter++ )
{
padapter = pNetInfo->AdapterArray[iter];
if ( ( padapter->InfoFlags & DNS_FLAG_IGNORE_ADAPTER ) ||
( padapter->RunFlags & RUN_FLAG_STOP_QUERY_ON_ADAPTER ) )
{
continue;
}
// if negative answer on adapter -- fine
if ( padapter->Status == DNS_ERROR_RCODE_NAME_ERROR ||
padapter->Status == DNS_INFO_NO_RECORDS )
{
ASSERT( padapter->RunFlags & RUN_FLAG_STOP_QUERY_ON_ADAPTER );
continue;
}
// note, the above should map one-to-one with query stop
ASSERT( !(padapter->RunFlags & RUN_FLAG_STOP_QUERY_ON_ADAPTER) );
// if adapter has no DNS server -- fine
// in this case PnP before useful, and the PnP event
// will flush the cache
if ( padapter->ServerCount == 0 )
{
continue;
}
// otherwise, this adapter was queried but could not produce a response
DNSDBG( TRACE, (
"IsCacheableNameError() -- FALSE\n"
"\tadapter %d (%S) did not receive response\n"
"\treturn status = %d\n"
"\treturn flags = %08x\n",
iter,
padapter->pszAdapterGuidName,
padapter->Status,
padapter->RunFlags ));
return FALSE;
}
return TRUE;
}
//
// Query name building utils
//
BOOL
ValidateQueryTld(
IN PSTR pTld
)
/*++
Routine Description:
Validate query TLD
Arguments:
pTld -- TLD to validate
Return Value:
TRUE if valid
FALSE otherwise
--*/
{
//
// numeric
//
if ( g_ScreenBadTlds & DNS_TLD_SCREEN_NUMERIC )
{
if ( Dns_IsNameNumeric_A( pTld ) )
{
return FALSE;
}
}
//
// bogus TLDs
//
if ( g_ScreenBadTlds & DNS_TLD_SCREEN_WORKGROUP )
{
if ( Dns_NameCompare_UTF8(
"workgroup",
pTld ))
{
return FALSE;
}
}
// not sure about these
// probably won't turn on screening by default
if ( g_ScreenBadTlds & DNS_TLD_SCREEN_DOMAIN )
{
if ( Dns_NameCompare_UTF8(
"domain",
pTld ))
{
return FALSE;
}
}
if ( g_ScreenBadTlds & DNS_TLD_SCREEN_OFFICE )
{
if ( Dns_NameCompare_UTF8(
"office",
pTld ))
{
return FALSE;
}
}
if ( g_ScreenBadTlds & DNS_TLD_SCREEN_HOME )
{
if ( Dns_NameCompare_UTF8(
"home",
pTld ))
{
return FALSE;
}
}
return TRUE;
}
BOOL
ValidateQueryName(
IN PQUERY_BLOB pBlob,
IN PSTR pName,
IN PSTR pDomain
)
/*++
Routine Description:
Validate name for wire query.
Arguments:
pBlob -- query blob
pName -- name; may be any sort of name
pDomain -- domain name to append
Return Value:
TRUE if name query will be valid.
FALSE otherwise.
--*/
{
WORD wtype;
PSTR pnameTld;
PSTR pdomainTld;
// no screening -- bail
if ( g_ScreenBadTlds == 0 )
{
return TRUE;
}
// only screening for standard types
// - A, AAAA, SRV
wtype = pBlob->wType;
if ( wtype != DNS_TYPE_A &&
wtype != DNS_TYPE_AAAA &&
wtype != DNS_TYPE_SRV )
{
return TRUE;
}
// get name TLD
pnameTld = Dns_GetTldForName( pName );
//
// if no domain appended
// - exclude single label
// - exclude bad TLD (numeric, bogus domain)
// - but allow root queries
//
// DCR: MS DCS screening
// screen
// _msdcs.<name>
// will probably be unappended query
//
if ( !pDomain )
{
if ( !pnameTld ||
!ValidateQueryTld( pnameTld ) )
{
goto Failed;
}
return TRUE;
}
//
// domain appended
// - exclude bad TLD (numeric, bogus domain)
// - exclude matching TLD
//
pdomainTld = Dns_GetTldForName( pDomain );
if ( !pdomainTld )
{
pdomainTld = pDomain;
}
if ( !ValidateQueryTld( pdomainTld ) )
{
goto Failed;
}
// screen repeated TLD
if ( g_ScreenBadTlds & DNS_TLD_SCREEN_REPEATED )
{
if ( Dns_NameCompare_UTF8(
pnameTld,
pdomainTld ) )
{
goto Failed;
}
}
return TRUE;
Failed:
DNSDBG( QUERY, (
"Failed invalid query name:\n"
"\tname %s\n"
"\tdomain %s\n",
pName,
pDomain ));
return FALSE;
}
PSTR
GetNextAdapterDomainName(
IN OUT PDNS_NETINFO pNetInfo
)
/*++
Routine Description:
Get next adapter domain name to query.
Arguments:
pNetInfo -- DNS Network info for query;
adapter data will be modified (InfoFlags field)
to indicate which adapter to query and which
to skip query on
Return Value:
Ptr to domain name (UTF8) to query.
NULL if no more domain names to query.
--*/
{
DWORD iter;
PSTR pqueryDomain = NULL;
DNSDBG( TRACE, ( "GetNextAdapterDomainName()\n" ));
if ( ! pNetInfo )
{
ASSERT( FALSE );
return NULL;
}
IF_DNSDBG( OFF )
{
DnsDbg_NetworkInfo(
"Net info to get adapter domain name from: ",
pNetInfo );
}
//
// check each adapter
// - first unqueried adapter with name is chosen
// - other adapters with
// - matching name => included in query
// - non-matching => turned OFF for query
//
// DCR: query on\off should use adapter dynamic flags
//
for ( iter = 0; iter < pNetInfo->AdapterCount; iter++ )
{
PDNS_ADAPTER padapter;
PSTR pdomain;
padapter = pNetInfo->AdapterArray[iter];
// netinfo should come in with name specific flags clean
DNS_ASSERT( !(padapter->RunFlags & RUN_FLAG_SINGLE_NAME_MASK) );
//
// ignore
// - ignored adapter OR
// - previously queried adapter domain
// note: it can't match any "fresh" domain we come up with
// as we always collect all matches
if ( (padapter->InfoFlags & DNS_FLAG_IGNORE_ADAPTER)
||
(padapter->RunFlags & RUN_FLAG_QUERIED_ADAPTER_DOMAIN) )
{
padapter->RunFlags |= RUN_FLAG_STOP_QUERY_ON_ADAPTER;
continue;
}
// no domain name -- always off
pdomain = padapter->pszAdapterDomain;
if ( !pdomain )
{
padapter->RunFlags |= (RUN_FLAG_QUERIED_ADAPTER_DOMAIN |
RUN_FLAG_STOP_QUERY_ON_ADAPTER);
continue;
}
// first "fresh" domain name -- save, turn on and flag as used
if ( !pqueryDomain )
{
pqueryDomain = pdomain;
padapter->RunFlags |= RUN_FLAG_QUERIED_ADAPTER_DOMAIN;
continue;
}
// other "fresh" domain names
// - if matches query domain => on for query
// - no match => off
if ( Dns_NameCompare_UTF8(
pqueryDomain,
pdomain ) )
{
padapter->RunFlags |= RUN_FLAG_QUERIED_ADAPTER_DOMAIN;
continue;
}
else
{
padapter->RunFlags |= RUN_FLAG_STOP_QUERY_ON_ADAPTER;
continue;
}
}
//
// if no adapter domain name -- clear STOP flag
// - all adapters participate in other names (name devolution)
//
if ( !pqueryDomain )
{
for ( iter = 0; iter < pNetInfo->AdapterCount; iter++ )
{
PDNS_ADAPTER padapter = pNetInfo->AdapterArray[iter];
padapter->RunFlags &= (~RUN_FLAG_SINGLE_NAME_MASK );
}
DNSDBG( INIT2, (
"GetNextAdapterDomainName out of adapter names.\n" ));
pNetInfo->ReturnFlags |= RUN_FLAG_QUERIED_ADAPTER_DOMAIN;
}
IF_DNSDBG( INIT2 )
{
if ( pqueryDomain )
{
DnsDbg_NetworkInfo(
"Net info after adapter name select: ",
pNetInfo );
}
}
DNSDBG( INIT2, (
"Leaving GetNextAdapterDomainName() => %s\n",
pqueryDomain ));
return pqueryDomain;
}
PSTR
GetNextDomainNameToAppend(
IN OUT PDNS_NETINFO pNetInfo,
OUT PDWORD pSuffixFlags
)
/*++
Routine Description:
Get next adapter domain name to query.
Arguments:
pNetInfo -- DNS Network info for query;
adapter data will be modified (RunFlags field)
to indicate which adapter to query and which
to skip query on
pSuffixFlags -- flags associated with the use of this suffix
Return Value:
Ptr to domain name (UTF8) to query.
NULL if no more domain names to query.
--*/
{
PSTR psearchName;
PSTR pdomain;
//
// search list if real search list
//
// if suffix flags zero, then this is REAL search list
// or is PDN name
//
psearchName = SearchList_GetNextName(
pNetInfo->pSearchList,
FALSE, // not reset
pSuffixFlags );
if ( psearchName && (*pSuffixFlags == 0) )
{
// found regular search name -- done
DNSDBG( INIT2, (
"getNextDomainName from search list => %s, %d\n",
psearchName,
*pSuffixFlags ));
return( psearchName );
}
//
// try adapter domain names
//
// but ONLY if search list is dummy; if real we only
// use search list entries
//
// DCR_CLEANUP: eliminate bogus search list
//
if ( pNetInfo->InfoFlags & DNS_FLAG_DUMMY_SEARCH_LIST
&&
! (pNetInfo->ReturnFlags & RUN_FLAG_QUERIED_ADAPTER_DOMAIN) )
{
pdomain = GetNextAdapterDomainName( pNetInfo );
if ( pdomain )
{
*pSuffixFlags = DNS_QUERY_USE_QUICK_TIMEOUTS;
DNSDBG( INIT2, (
"getNextDomainName from adapter domain name => %s, %d\n",
pdomain,
*pSuffixFlags ));
// back the search list up one tick
// we queried through it above, so if it was returing
// a name, we need to get that name again on next query
if ( psearchName )
{
ASSERT( pNetInfo->pSearchList->CurrentNameIndex > 0 );
pNetInfo->pSearchList->CurrentNameIndex--;
}
return( pdomain );
}
}
//
// DCR_CLEANUP: remove devolution from search list and do explicitly
// - its cheap (or do it once and save, but store separately)
//
//
// finally use and devolved search names (or other nonsense)
//
*pSuffixFlags = DNS_QUERY_USE_QUICK_TIMEOUTS;
DNSDBG( INIT2, (
"getNextDomainName from devolution\\other => %s, %d\n",
psearchName,
*pSuffixFlags ));
return( psearchName );
}
PSTR
GetNextQueryName(
IN OUT PQUERY_BLOB pBlob
)
/*++
Routine Description:
Get next name to query.
Arguments:
pBlob - blob of query information
Uses:
NameOriginalWire
NameAttributes
QueryCount
pNetworkInfo
Sets:
NameWire -- set with appended wire name
pNetworkInfo -- runtime flags set to indicate which adapters are
queried
NameFlags -- set with properties of name
fAppendedName -- set when name appended
Return Value:
Ptr to name to query with.
- will be orginal name on first query if name is multilabel name
- otherwise will be NameWire buffer which will contain appended name
composed of pszName and some domain name
NULL if no more names to append
--*/
{
PSTR pnameOrig = pBlob->NameOriginalWire;
PSTR pdomainName = NULL;
PSTR pnameBuf;
DWORD queryCount = pBlob->QueryCount;
DWORD nameAttributes = pBlob->NameAttributes;
DNSDBG( TRACE, (
"GetNextQueryName( %p )\n",
pBlob ));
// default suffix flags
pBlob->NameFlags = 0;
//
// FQDN
// - send FQDN only
//
if ( nameAttributes & DNS_NAME_IS_FQDN )
{
if ( queryCount == 0 )
{
#if 0
// currently won't even validate FQDN
if ( ValidateQueryName(
pBlob,
pnameOrig,
NULL ) )
{
return pnameOrig;
}
#endif
return pnameOrig;
}
DNSDBG( QUERY, (
"No append for FQDN name %s -- end query.\n",
pnameOrig ));
return NULL;
}
//
// multilabel
// - first pass on name itself -- if valid
//
// DCR: intelligent choice on multi-label whether append first
// or go to wire first (example foo.ntdev) could append
// first
//
if ( nameAttributes & DNS_NAME_MULTI_LABEL )
{
if ( queryCount == 0 )
{
if ( ValidateQueryName(
pBlob,
pnameOrig,
NULL ) )
{
return pnameOrig;
}
}
if ( !g_AppendToMultiLabelName )
{
DNSDBG( QUERY, (
"No append allowed on multi-label name %s -- end query.\n",
pnameOrig ));
return NULL;
}
// falls through to appending on multi-label names
}
//
// not FQDN -- append a domain name
// - next search name (if available)
// - otherwise next adapter domain name
//
pnameBuf = pBlob->NameWire;
while ( 1 )
{
pdomainName = GetNextDomainNameToAppend(
pBlob->pNetworkInfo,
& pBlob->NameFlags );
if ( !pdomainName )
{
DNSDBG( QUERY, (
"No more domain names to append -- end query\n" ));
return NULL;
}
if ( !ValidateQueryName(
pBlob,
pnameOrig,
pdomainName ) )
{
continue;
}
// append domain name to name
if ( Dns_NameAppend_A(
pnameBuf,
DNS_MAX_NAME_BUFFER_LENGTH,
pnameOrig,
pdomainName ) )
{
pBlob->fAppendedName = TRUE;
break;
}
}
DNSDBG( QUERY, (
"GetNextQueryName() result => %s\n",
pnameBuf ));
return pnameBuf;
}
DNS_STATUS
QueryDirectEx(
IN OUT PDNS_MSG_BUF * ppMsgResponse,
OUT PDNS_RECORD * ppResponseRecords,
IN PDNS_HEADER pHeader,
IN BOOL fNoHeaderCounts,
IN PDNS_NAME pszQuestionName,
IN WORD wQuestionType,
IN PDNS_RECORD pRecords,
IN DWORD dwFlags,
IN PIP_ARRAY aipDnsServers,
IN OUT PDNS_NETINFO pNetInfo
)
/*++
Routine Description:
Query.
Arguments:
ppMsgResponse -- addr to recv ptr to response buffer; caller MUST
free buffer
ppResponseRecord -- address to receive ptr to record list returned from query
pHead -- DNS header to send
fNoHeaderCounts - do NOT include record counts in copying header
pszQuestionName -- DNS name to query;
Unicode string if dwFlags has DNSQUERY_UNICODE_NAME set.
ANSI string otherwise.
wType -- query type
pRecords -- address to receive ptr to record list returned from query
dwFlags -- query flags
aipDnsServers -- specific DNS servers to query;
OPTIONAL, if specified overrides normal list associated with machine
pDnsNetAdapters -- DNS servers to query; if NULL get current list
Return Value:
ERROR_SUCCESS if successful.
Error code on failure.
--*/
{
PDNS_MSG_BUF psendMsg;
DNS_STATUS status = DNS_ERROR_NO_MEMORY;
DNSDBG( QUERY, (
"QueryDirectEx()\n"
"\tname %s\n"
"\ttype %d\n"
"\theader %p\n"
"\t - counts %d\n"
"\trecords %p\n"
"\tflags %08x\n"
"\trecv msg %p\n"
"\trecv records %p\n"
"\tserver IPs %p\n"
"\tadapter list %p\n",
pszQuestionName,
wQuestionType,
pHeader,
fNoHeaderCounts,
pRecords,
dwFlags,
ppMsgResponse,
ppResponseRecords,
aipDnsServers,
pNetInfo ));
//
// build send packet
//
psendMsg = Dns_BuildPacket(
pHeader,
fNoHeaderCounts,
pszQuestionName,
wQuestionType,
pRecords,
dwFlags,
FALSE // query, not an update
);
if ( !psendMsg )
{
status = ERROR_INVALID_NAME;
goto Cleanup;
}
#if MULTICAST_ENABLED
//
// QUESTION: mcast test is not complete here
// - should first test that we actually do it
// including whether we have DNS servers
// FIXME: then when we do do it -- encapsulate it
// ShouldMulicastQuery()
//
// Check to see if name is for something in the multicast local domain.
// If so, set flag to multicast this query only.
//
if ( Dns_NameCompareEx( pszQuestionName,
( dwFlags & DNSQUERY_UNICODE_NAME ) ?
(LPSTR) MULTICAST_DNS_LOCAL_DOMAIN_W :
MULTICAST_DNS_LOCAL_DOMAIN,
0,
( dwFlags & DNSQUERY_UNICODE_NAME ) ?
DnsCharSetUnicode :
DnsCharSetUtf8 ) ==
DnsNameCompareRightParent )
{
dwFlags |= DNS_QUERY_MULTICAST_ONLY;
}
#endif
//
// send query and receive response
//
Trace_LogQueryEvent(
psendMsg,
wQuestionType );
status = Dns_SendAndRecv(
psendMsg,
ppMsgResponse,
ppResponseRecords,
dwFlags,
aipDnsServers,
pNetInfo );
Trace_LogResponseEvent(
psendMsg,
( ppResponseRecords && *ppResponseRecords )
? (*ppResponseRecords)->wType
: 0,
status );
Cleanup:
FREE_HEAP( psendMsg );
DNSDBG( QUERY, (
"Leaving QueryDirectEx(), status = %s (%d)\n",
Dns_StatusString(status),
status ));
return( status );
}
DNS_STATUS
Query_SingleName(
IN OUT PQUERY_BLOB pBlob
)
/*++
Routine Description:
Query single name.
Arguments:
pBlob - query blob
Return Value:
ERROR_SUCCESS if successful.
Error code on failure.
--*/
{
PDNS_MSG_BUF psendMsg = NULL;
DNS_STATUS status = DNS_ERROR_NO_MEMORY;
DWORD flags = pBlob->Flags;
DNSDBG( QUERY, (
"Query_SingleName( %p )\n",
pBlob ));
IF_DNSDBG( QUERY )
{
DnsDbg_QueryBlob(
"Enter Query_SingleName()",
pBlob );
}
//
// cache\hostfile callback on appended name
// - note that queried name was already done
// (in resolver or in Query_Main())
//
if ( pBlob->pfnQueryCache && pBlob->fAppendedName )
{
if ( (pBlob->pfnQueryCache)( pBlob ) )
{
status = pBlob->Status;
goto Cleanup;
}
}
//
// if wire disallowed -- stop here
//
if ( flags & DNS_QUERY_NO_WIRE_QUERY )
{
status = DNS_ERROR_NAME_NOT_FOUND_LOCALLY;
pBlob->Status = status;
goto Cleanup;
}
//
// build send packet
//
psendMsg = Dns_BuildPacket(
NULL, // no header
0, // no header counts
pBlob->pNameWire,
pBlob->wType,
NULL, // no records
flags,
FALSE // query, not an update
);
if ( !psendMsg )
{
status = DNS_ERROR_INVALID_NAME;
goto Cleanup;
}
#if MULTICAST_ENABLED
//
// QUESTION: mcast test is not complete here
// - should first test that we actually do it
// including whether we have DNS servers
// FIXME: then when we do do it -- encapsulate it
// ShouldMulicastQuery()
//
// Check to see if name is for something in the multicast local domain.
// If so, set flag to multicast this query only.
//
if ( Dns_NameCompareEx(
pBlob->pName,
( flags & DNSQUERY_UNICODE_NAME )
? (LPSTR) MULTICAST_DNS_LOCAL_DOMAIN_W
: MULTICAST_DNS_LOCAL_DOMAIN,
0,
( flags & DNSQUERY_UNICODE_NAME )
? DnsCharSetUnicode
: DnsCharSetUtf8 )
== DnsNameCompareRightParent )
{
flags |= DNS_QUERY_MULTICAST_ONLY;
}
#endif
//
// send query and receive response
//
Trace_LogQueryEvent(
psendMsg,
pBlob->wType );
status = Dns_SendAndRecv(
psendMsg,
(flags & DNS_QUERY_RETURN_MESSAGE)
? &pBlob->pRecvMsg
: NULL,
& pBlob->pRecords,
flags,
pBlob->pDnsServers,
pBlob->pNetworkInfo
);
Trace_LogResponseEvent(
psendMsg,
( pBlob->pRecords )
? (pBlob->pRecords)->wType
: 0,
status );
Cleanup:
FREE_HEAP( psendMsg );
DNSDBG( QUERY, (
"Leaving Query_SingleName(), status = %s (%d)\n",
Dns_StatusString(status),
status ));
IF_DNSDBG( QUERY )
{
DnsDbg_QueryBlob(
"Blob leaving Query_SingleName()",
pBlob );
}
return( status );
}
DNS_STATUS
Query_Main(
IN OUT PQUERY_BLOB pBlob
)
/*++
Routine Description:
Main query routine.
Does all the query processing
- local lookup
- name appending
- cache\hostfile lookup on appended name
- query to server
Arguments:
pBlob -- query info blob
Return Value:
ERROR_SUCCESS if successful response.
DNS_INFO_NO_RECORDS on no records for type response.
DNS_ERROR_RCODE_NAME_ERROR on name error.
DNS_ERROR_INVALID_NAME on bad name.
None
--*/
{
DNS_STATUS status = DNS_ERROR_NAME_NOT_FOUND_LOCALLY;
PSTR pdomainName = NULL;
PDNS_RECORD precords;
DWORD queryFlags;
DWORD suffixFlags = 0;
DWORD nameAttributes;
DNS_STATUS bestQueryStatus = ERROR_SUCCESS;
BOOL fcacheNegative = TRUE;
DWORD flagsIn = pBlob->Flags;
PDNS_NETINFO pnetInfo = pBlob->pNetworkInfo;
DWORD nameLength;
DWORD bufLength;
DWORD queryCount;
DNSDBG( TRACE, (
"Query_Main( %p )\n"
"\t%S, f=%08x, type=%d, time = %d\n",
pBlob,
pBlob->pNameOrig,
flagsIn,
pBlob->wType,
Dns_GetCurrentTimeInSeconds()
));
//
// clear out params
//
pBlob->pRecords = NULL;
pBlob->pLocalRecords = NULL;
pBlob->fCacheNegative = FALSE;
pBlob->fNoIpLocal = FALSE;
pBlob->NetFailureStatus = ERROR_SUCCESS;
//
// convert name to wire format
//
bufLength = DNS_MAX_NAME_BUFFER_LENGTH;
nameLength = Dns_NameCopy(
pBlob->NameOriginalWire,
& bufLength,
(PSTR) pBlob->pNameOrig,
0, // name is NULL terminated
DnsCharSetUnicode,
DnsCharSetWire );
if ( nameLength == 0 )
{
return DNS_ERROR_INVALID_NAME;
}
nameLength--;
pBlob->NameLength = nameLength;
pBlob->pNameOrigWire = pBlob->NameOriginalWire;
//
// determine name properties
// - determines number and order of name queries
//
nameAttributes = Dns_GetNameAttributes( pBlob->NameOriginalWire );
if ( flagsIn & DNS_QUERY_TREAT_AS_FQDN )
{
nameAttributes |= DNS_NAME_IS_FQDN;
}
pBlob->NameAttributes = nameAttributes;
//
// hostfile lookup
// - called in process
// - hosts file lookup allowed
// -> then must do hosts file lookup before appending\queries
//
// note: this matches the hostsfile\cache lookup in resolver
// before call; hosts file queries to appended names are
// handled together by callback in Query_SingleName()
//
// we MUST make this callback here, because it must PRECEDE
// the local name call, as some customers specifically direct
// some local mappings in the hosts file
//
if ( pBlob->pfnQueryCache == QueryHostFile
&&
! (flagsIn & DNS_QUERY_NO_HOSTS_FILE) )
{
pBlob->pNameWire = pBlob->pNameOrigWire;
if ( QueryHostFile( pBlob ) )
{
status = pBlob->Status;
goto Done;
}
}
//
// check for local name
// - if successful, skip wire query
//
if ( ! (flagsIn & DNS_QUERY_NO_LOCAL_NAME) )
{
status = GetRecordsForLocalName( pBlob );
if ( status == ERROR_SUCCESS &&
!pBlob->fNoIpLocal )
{
DNS_ASSERT( pBlob->pRecords &&
pBlob->pRecords == pBlob->pLocalRecords );
goto Done;
}
}
//
// query until
// - successfull
// - exhaust names to query with
//
queryCount = 0;
while ( 1 )
{
PSTR pqueryName;
// clean name specific info from list
if ( queryCount != 0 )
{
NetInfo_Clean(
pnetInfo,
CLEAR_LEVEL_SINGLE_NAME );
}
//
// next query name
//
pqueryName = GetNextQueryName( pBlob );
if ( !pqueryName )
{
if ( queryCount == 0 )
{
status = DNS_ERROR_INVALID_NAME;
}
break;
}
pBlob->QueryCount = ++queryCount;
pBlob->pNameWire = pqueryName;
DNSDBG( QUERY, (
"Query %d is for name %s\n",
queryCount,
pqueryName ));
//
// set flags
// - passed in flags
// - unicode results
// - flags for this particular suffix
pBlob->Flags = flagsIn | pBlob->NameFlags;
//
// clear any previously received records (shouldn't be any)
//
if ( pBlob->pRecords )
{
DNS_ASSERT( FALSE );
Dns_RecordListFree( pBlob->pRecords );
pBlob->pRecords = NULL;
}
//
// do the query for name
// includes
// - cache or hostfile lookup
// - wire query
//
status = Query_SingleName( pBlob );
//
// clean out records on "non-response"
//
// DCR: need to fix record return
// - should keep records on any response (best response)
// just make sure NO_RECORDS rcode is mapped
//
// the only time we keep them is FAZ
// - ALLOW_EMPTY_AUTH flag set
// - sending FQDN (or more precisely doing single query)
//
precords = pBlob->pRecords;
if ( precords )
{
if ( IsEmptyDnsResponse( precords ) )
{
if ( (flagsIn & DNS_QUERY_ALLOW_EMPTY_AUTH_RESP)
&&
( (nameAttributes & DNS_NAME_IS_FQDN)
||
((nameAttributes & DNS_NAME_MULTI_LABEL) &&
!g_AppendToMultiLabelName ) ) )
{
// stop here as caller (probably FAZ code)
// wants to get the authority records
DNSDBG( QUERY, (
"Returning empty query response with authority records.\n" ));
break;
}
else
{
Dns_RecordListFree( precords );
pBlob->pRecords = NULL;
if ( status == NO_ERROR )
{
status = DNS_INFO_NO_RECORDS;
}
}
}
}
// successful query -- done
if ( status == ERROR_SUCCESS )
{
RTL_ASSERT( precords );
break;
}
#if 0
//
// DCR_FIX0: lost adapter timeout from early in multi-name query
// - callback here or some other approach
//
// this is resolver version
//
// reset server priorities on failures
// do here to avoid washing out info in retry with new name
//
if ( status != ERROR_SUCCESS &&
(pnetInfo->ReturnFlags & DNS_FLAG_RESET_SERVER_PRIORITY) )
{
if ( g_AdapterTimeoutCacheTime &&
Dns_DisableTimedOutAdapters( pnetInfo ) )
{
fadapterTimedOut = TRUE;
SetKnownTimedOutAdapter();
}
}
//
// DCR_CLEANUP: lost intermediate timed out adapter deal
//
if ( status != NO_ERROR &&
(pnetInfo->ReturnFlags & DNS_FLAG_RESET_SERVER_PRIORITY) )
{
Dns_DisableTimedOutAdapters( pnetInfo );
}
#endif
//
// save first query error (for some errors)
//
if ( queryCount == 1 &&
( status == DNS_ERROR_RCODE_NAME_ERROR ||
status == DNS_INFO_NO_RECORDS ||
status == DNS_ERROR_INVALID_NAME ||
status == DNS_ERROR_RCODE_SERVER_FAILURE ||
status == DNS_ERROR_RCODE_FORMAT_ERROR ) )
{
DNSDBG( QUERY, (
"Saving bestQueryStatus %d\n",
status ));
bestQueryStatus = status;
}
//
// continue with other queries on some errors
//
// on NAME_ERROR or NO_RECORDS response
// - check if this negative result will be
// cacheable, if it holds up
//
// note: the reason we check every time is that when the
// query involves several names, one or more may fail
// with one network timing out, YET the final name
// queried indeed is a NAME_ERROR everywhere; hence
// we can not do the check just once on the final
// negative response;
// in short, every negative response must be determinative
// in order for us to cache
//
if ( status == DNS_ERROR_RCODE_NAME_ERROR ||
status == DNS_INFO_NO_RECORDS )
{
if ( fcacheNegative )
{
fcacheNegative = IsCacheableNameError( pnetInfo );
}
if ( status == DNS_INFO_NO_RECORDS )
{
DNSDBG( QUERY, (
"Saving bestQueryStatus %d\n",
status ));
bestQueryStatus = status;
}
continue;
}
// server failure may indicate intermediate or remote
// server timeout and hence also makes any final
// name error determination uncacheable
else if ( status == DNS_ERROR_RCODE_SERVER_FAILURE )
{
fcacheNegative = FALSE;
continue;
}
// busted name errors
// - just continue with next query
else if ( status == DNS_ERROR_INVALID_NAME ||
status == DNS_ERROR_RCODE_FORMAT_ERROR )
{
continue;
}
//
// other errors -- ex. timeout and winsock -- are terminal
//
else
{
fcacheNegative = FALSE;
break;
}
}
DNSDBG( QUERY, (
"Query_Main() -- name loop termination\n"
"\tstatus = %d\n"
"\tquery count = %d\n",
status,
queryCount ));
//
// if no queries then invalid name
// - either name itself is invalid
// OR
// - single part name and don't have anything to append
//
DNS_ASSERT( queryCount != 0 ||
status == DNS_ERROR_INVALID_NAME );
//
// success -- prioritize record data
//
// to prioritize
// - prioritize is set
// - have more than one A record
// - can get IP list
//
// note: need the callback because resolver uses directly
// local copy of IP address info, whereas direct query
// RPC's a copy over from the resolver
//
// alternative would be some sort of "set IP source"
// function that resolver would call when there's a
// new list; then could have common function that
// picks up source if available or does RPC
//
if ( status == ERROR_SUCCESS )
{
if ( g_PrioritizeRecordData &&
Dns_RecordListCount( precords, DNS_TYPE_A ) > 1 &&
pBlob->pfnGetAddrArray )
{
PDNS_ADDR_ARRAY paddrArray = (pBlob->pfnGetAddrArray)();
if ( paddrArray )
{
pBlob->pRecords = Dns_PrioritizeRecordSetEx(
precords,
paddrArray );
FREE_HEAP( paddrArray );
}
}
}
//
// no-op common negative response
// doing this for perf to skip extensive status code check below
//
else if ( status == DNS_ERROR_RCODE_NAME_ERROR ||
status == DNS_INFO_NO_RECORDS )
{
// no-op
}
//
// timeout indicates possible network problem
// winsock errors indicate definite network problem
//
else if (
status == ERROR_TIMEOUT ||
status == WSAEFAULT ||
status == WSAENOTSOCK ||
status == WSAENETDOWN ||
status == WSAENETUNREACH ||
status == WSAEPFNOSUPPORT ||
status == WSAEAFNOSUPPORT ||
status == WSAEHOSTDOWN ||
status == WSAEHOSTUNREACH )
{
pBlob->NetFailureStatus = status;
}
#if 0
//
// DCR: not sure when to free message buffer
//
// - it is reused in Dns_QueryLib call, so no leak
// - point is when to return it
// - old QuickQueryEx() would dump when going around again?
// not sure of the point of that
//
//
// going around again -- free up message buffer
//
if ( ppMsgResponse && *ppMsgResponse )
{
FREE_HEAP( *ppMsgResponse );
*ppMsgResponse = NULL;
}
#endif
//
// use NO-IP local name?
//
// if matched local name but had no IPs (IP6 currently)
// then use default here if not successful wire query
//
if ( pBlob->fNoIpLocal )
{
if ( status != ERROR_SUCCESS )
{
Dns_RecordListFree( pBlob->pRecords );
pBlob->pRecords = pBlob->pLocalRecords;
status = ERROR_SUCCESS;
pBlob->Status = status;
}
else
{
Dns_RecordListFree( pBlob->pLocalRecords );
pBlob->pLocalRecords = NULL;
}
}
//
// if error, use "best" error
// this is either
// - original query response
// - or NO_RECORDS response found later
//
if ( status != ERROR_SUCCESS && bestQueryStatus )
{
status = bestQueryStatus;
pBlob->Status = status;
}
//
// set negative response cacheability
//
pBlob->fCacheNegative = fcacheNegative;
Done:
DNS_ASSERT( !pBlob->pLocalRecords ||
pBlob->pLocalRecords == pBlob->pRecords );
DNSDBG( TRACE, (
"Leave Query_Main()\n"
"\tstatus = %d\n"
"\ttime = %d\n",
status,
Dns_GetCurrentTimeInSeconds()
));
IF_DNSDBG( QUERY )
{
DnsDbg_QueryBlob(
"Blob leaving Query_Main()",
pBlob );
}
//
// DCR_HACK: remove me
//
// must return some records on success query
//
// not sure this is true on referral -- if so it's because we flag
// as referral
//
ASSERT( status != ERROR_SUCCESS || pBlob->pRecords != NULL );
return status;
}
DNS_STATUS
Query_InProcess(
IN OUT PQUERY_BLOB pBlob
)
/*++
Routine Description:
Main direct in-process query routine.
Arguments:
pBlob -- query info blob
Return Value:
ERROR_SUCCESS if successful.
DNS RCODE error for RCODE response.
DNS_INFO_NO_RECORDS for no records response.
ERROR_TIMEOUT on complete lookup failure.
ErrorCode on local failure.
--*/
{
DNS_STATUS status = NO_ERROR;
PDNS_NETINFO pnetInfo;
PDNS_NETINFO pnetInfoLocal = NULL;
PDNS_NETINFO pnetInfoOriginal;
DNS_STATUS statusNetFailure = NO_ERROR;
DNSDBG( TRACE, (
"Query_InProcess( %p )\n",
pBlob ));
//
// skip queries in "net down" situation
//
if ( IsKnownNetFailure() )
{
status = GetLastError();
goto Cleanup;
}
//
// get network info
//
pnetInfo = pnetInfoOriginal = pBlob->pNetworkInfo;
//
// explicit DNS server list -- build into network info
// - requires info from current list for search list or PDN
// - then dump current list and use private version
//
if ( pBlob->pDnsServers )
{
pnetInfo = NetInfo_CreateFromIpArray(
pBlob->pDnsServers,
0, // no specific server
TRUE, // build search info
pnetInfo // use existing netinfo
);
if ( !pnetInfo )
{
status = DNS_ERROR_NO_MEMORY;
goto Cleanup;
}
pnetInfoLocal = pnetInfo;
}
//
// no network info -- get it
//
else if ( !pnetInfo )
{
pnetInfoLocal = pnetInfo = GetNetworkInfo();
if ( ! pnetInfo )
{
status = DNS_ERROR_NO_DNS_SERVERS;
goto Cleanup;
}
}
pBlob->pNetworkInfo = pnetInfo;
//
// make actual query to DNS servers
//
pBlob->pfnQueryCache = QueryHostFile;
pBlob->pfnGetAddrArray = DnsGetLocalAddrArray;
status = Query_Main( pBlob );
//
// save net failure
// - but not if passed in network info
// only meaningful if its standard info
//
// DCR: fix statusNetFailure mess
//
if ( statusNetFailure )
{
if ( !pBlob->pDnsServers )
{
SetKnownNetFailure( status );
}
}
//
// cleanup
//
Cleanup:
NetInfo_Free( pnetInfoLocal );
pBlob->pNetworkInfo = pnetInfoOriginal;
GUI_MODE_SETUP_WS_CLEANUP( g_InNTSetupMode );
return status;
}
//
// Query utilities
//
DNS_STATUS
GetDnsServerRRSet(
OUT PDNS_RECORD * ppRecord,
IN BOOLEAN fUnicode
)
/*++
Routine Description:
Create record list of None.
Arguments:
None.
Return Value:
None.
--*/
{
PDNS_NETINFO pnetInfo;
DWORD iter;
PDNS_RECORD prr;
DNS_RRSET rrSet;
DNS_CHARSET charSet = fUnicode ? DnsCharSetUnicode : DnsCharSetUtf8;
DNSDBG( QUERY, (
"GetDnsServerRRSet()\n" ));
DNS_RRSET_INIT( rrSet );
pnetInfo = GetNetworkInfo();
if ( !pnetInfo )
{
goto Done;
}
//
// loop through all adapters build record for each DNS server
//
for ( iter = 0;
iter < pnetInfo->AdapterCount;
iter++ )
{
PDNS_ADAPTER padapter = pnetInfo->AdapterArray[iter];
PSTR pname;
DWORD jiter;
if ( !padapter )
{
continue;
}
// DCR: goofy way to expose aliases
//
// if register the adapter's domain name, make it record name
// this
pname = padapter->pszAdapterDomain;
if ( !pname ||
!( padapter->InfoFlags & DNS_FLAG_REGISTER_DOMAIN_NAME ) )
{
pname = ".";
}
for ( jiter = 0; jiter < padapter->ServerCount; jiter++ )
{
// DCR: IP6 DNS servers
IP_UNION ipUnion;
IPUNION_SET_IP4( &ipUnion, padapter->ServerArray[jiter].IpAddress );
prr = Dns_CreateForwardRecord(
pname,
& ipUnion,
0, // no TTL
DnsCharSetUtf8, // name is UTF8
charSet // result set
);
if ( prr )
{
prr->Flags.S.Section = DNSREC_ANSWER;
DNS_RRSET_ADD( rrSet, prr );
}
}
}
Done:
NetInfo_Free( pnetInfo );
*ppRecord = prr = rrSet.pFirstRR;
DNSDBG( QUERY, (
"Leave GetDnsServerRRSet() => %d\n",
(prr ? ERROR_SUCCESS : DNS_ERROR_NO_DNS_SERVERS) ));
return (prr ? ERROR_SUCCESS : DNS_ERROR_NO_DNS_SERVERS);
}
//
// DNS Query API
//
DNS_STATUS
WINAPI
privateNarrowToWideQuery(
IN PCSTR pszName,
IN WORD wType,
IN DWORD Options,
IN PIP_ARRAY pDnsServers OPTIONAL,
OUT PDNS_RECORD * ppResultSet OPTIONAL,
IN OUT PDNS_MSG_BUF * ppMessageResponse OPTIONAL,
IN DNS_CHARSET CharSet
)
/*++
Routine Description:
Convert narrow to wide query.
This routine simple avoids duplicate code in ANSI
and UTF8 query routines.
Arguments:
pszName -- name to query
wType -- type of query
Options -- flags to query
pDnsServers -- array of DNS servers to use in query
ppResultSet -- addr to receive result DNS records
ppMessageResponse -- addr to receive response message
CharSet -- char set of original query
Return Value:
ERROR_SUCCESS on success.
DNS RCODE error on query with RCODE
DNS_INFO_NO_RECORDS on no records response.
ErrorCode on failure.
--*/
{
DNS_STATUS status = NO_ERROR;
PDNS_RECORD prrList = NULL;
PWSTR pwideName = NULL;
WORD nameLength;
if ( !pszName )
{
return ERROR_INVALID_PARAMETER;
}
nameLength = (WORD) strlen( pszName );
pwideName = ALLOCATE_HEAP( (nameLength + 1) * sizeof(WCHAR) );
if ( !pwideName )
{
return DNS_ERROR_NO_MEMORY;
}
if ( !Dns_NameCopy(
(PSTR) pwideName,
NULL,
(PSTR) pszName,
nameLength,
CharSet,
DnsCharSetUnicode ) )
{
status = ERROR_INVALID_NAME;
goto Done;
}
status = DnsQuery_W(
pwideName,
wType,
Options,
pDnsServers,
ppResultSet ? &prrList : NULL,
ppMessageResponse
);
//
// convert result records back to ANSI (or UTF8)
//
if ( ppResultSet && prrList )
{
*ppResultSet = Dns_RecordSetCopyEx(
prrList,
DnsCharSetUnicode,
CharSet
);
if ( ! *ppResultSet )
{
status = DNS_ERROR_NO_MEMORY;
}
Dns_RecordListFree( prrList );
}
//
// cleanup
//
Done:
FREE_HEAP( pwideName );
return status;
}
DNS_STATUS
WINAPI
DnsQuery_UTF8(
IN PCSTR pszName,
IN WORD wType,
IN DWORD Options,
IN PIP_ARRAY pDnsServers OPTIONAL,
OUT PDNS_RECORD * ppResultSet OPTIONAL,
IN OUT PDNS_MSG_BUF * ppMessageResponse OPTIONAL
)
/*++
Routine Description:
Public UTF8 query.
Arguments:
pszName -- name to query
wType -- type of query
Options -- flags to query
pDnsServers -- array of DNS servers to use in query
ppResultSet -- addr to receive result DNS records
ppMessageResponse -- addr to receive response message
Return Value:
ERROR_SUCCESS on success.
DNS RCODE error on query with RCODE
DNS_INFO_NO_RECORDS on no records response.
ErrorCode on failure.
--*/
{
return privateNarrowToWideQuery(
pszName,
wType,
Options,
pDnsServers,
ppResultSet,
ppMessageResponse,
DnsCharSetUtf8
);
}
DNS_STATUS
WINAPI
DnsQuery_A(
IN PCSTR pszName,
IN WORD wType,
IN DWORD Options,
IN PIP_ARRAY pDnsServers OPTIONAL,
OUT PDNS_RECORD * ppResultSet OPTIONAL,
IN OUT PDNS_MSG_BUF * ppMessageResponse OPTIONAL
)
/*++
Routine Description:
Public ANSI query.
Arguments:
pszName -- name to query
wType -- type of query
Options -- flags to query
pDnsServers -- array of DNS servers to use in query
ppResultSet -- addr to receive result DNS records
ppMessageResponse -- addr to receive resulting message
Return Value:
ERROR_SUCCESS on success.
DNS RCODE error on query with RCODE
DNS_INFO_NO_RECORDS on no records response.
ErrorCode on failure.
--*/
{
return privateNarrowToWideQuery(
pszName,
wType,
Options,
pDnsServers,
ppResultSet,
ppMessageResponse,
DnsCharSetAnsi
);
}
DNS_STATUS
WINAPI
DnsQuery_W(
IN PCWSTR pwsName,
IN WORD wType,
IN DWORD Options,
IN PIP_ARRAY pDnsServers OPTIONAL,
IN OUT PDNS_RECORD * ppResultSet OPTIONAL,
IN OUT PDNS_MSG_BUF * ppMessageResponse OPTIONAL
)
/*++
Routine Description:
Public unicode query API
Note, this unicode version is the main routine.
The other public API call back through it.
Arguments:
pszName -- name to query
wType -- type of query
Options -- flags to query
pDnsServers -- array of DNS servers to use in query
ppResultSet -- addr to receive result DNS records
ppMessageResponse -- addr to receive resulting message
Return Value:
ERROR_SUCCESS on success.
DNS RCODE error on query with RCODE
DNS_INFO_NO_RECORDS on no records response.
ErrorCode on failure.
--*/
{
DNS_STATUS status = NO_ERROR;
PDNS_NETINFO pnetInfo = NULL;
PDNS_RECORD prpcRecord = NULL;
DWORD rpcStatus = NO_ERROR;
PQUERY_BLOB pblob;
PWSTR pnameLocal = NULL;
DNSDBG( TRACE, (
"\n\nDnsQuery_W()\n"
"\tName = %S\n"
"\twType = %d\n"
"\tOptions = %08x\n"
"\tpDnsServers = %p\n"
"\tppMessage = %p\n",
pwsName,
wType,
Options,
pDnsServers,
ppMessageResponse ));
//
// must ask for some kind of results
//
if ( !ppResultSet && !ppMessageResponse )
{
return ERROR_INVALID_PARAMETER;
}
//
// NULL name indicates localhost lookup
//
// DCR: NULL name lookup for localhost could be improved
// - support NULL all the way through to wire
// - have local IP routines just accept it
//
if ( !pwsName )
{
pnameLocal = (PWSTR) Reg_GetHostName( DnsCharSetUnicode );
if ( !pnameLocal )
{
return DNS_ERROR_NAME_NOT_FOUND_LOCALLY;
}
pwsName = (PCWSTR) pnameLocal;
Options |= DNS_QUERY_CACHE_ONLY;
}
// clear OUT params
if ( ppResultSet )
{
*ppResultSet = NULL;
}
if ( ppMessageResponse )
{
*ppMessageResponse = NULL;
}
//
// IP string queries
//
if ( ppResultSet )
{
PDNS_RECORD prr;
prr = Dns_CreateRecordForIpString_W(
pwsName,
wType,
IPSTRING_RECORD_TTL );
if ( prr )
{
*ppResultSet = prr;
status = ERROR_SUCCESS;
goto Done;
}
}
//
// empty type A query get DNS servers
//
// DCR_CLEANUP: DnsQuery empty name query for DNS servers?
// need better\safer approach to this
// is this SDK doc'd
//
if ( ppResultSet &&
!ppMessageResponse &&
wType == DNS_TYPE_A &&
( !wcscmp( pwsName, L"" ) ||
!wcscmp( pwsName, DNS_SERVER_QUERY_NAME ) ) )
{
status = GetDnsServerRRSet(
ppResultSet,
TRUE // unicode
);
goto Done;
}
//
// BYPASS_CACHE
// - required if want message buffer or specify server
// list -- just set flag
// - incompatible with CACHE_ONLY
// - required to get EMPTY_AUTH_RESPONSE
//
if ( ppMessageResponse ||
pDnsServers ||
(Options & DNS_QUERY_ALLOW_EMPTY_AUTH_RESP) )
{
Options |= DNS_QUERY_BYPASS_CACHE;
//Options |= DNS_QUERY_NO_CACHE_DATA;
}
//
// do direct query?
// - not RPC-able type
// - want message buffer
// - specifying DNS servers
// - want EMPTY_AUTH response records
//
// DCR: currently by-passing for type==ALL
// this may be too common to do that; may want to
// go to cache then determine if security records
// or other stuff require us to query in process
//
// DCR: not clear what the EMPTY_AUTH benefit is
//
// DCR: currently BYPASSing whenever BYPASS is set
// because otherwise we miss the hosts file
// if fix so lookup in cache, but screen off non-hosts
// data, then could resume going to cache
//
if ( !Dns_IsRpcRecordType(wType) &&
!(Options & DNS_QUERY_CACHE_ONLY) )
{
goto InProcessQuery;
}
if ( Options & DNS_QUERY_BYPASS_CACHE )
#if 0
if ( (Options & DNS_QUERY_BYPASS_CACHE) &&
( ppMessageResponse ||
pDnsServers ||
(Options & DNS_QUERY_ALLOW_EMPTY_AUTH_RESP) ) )
#endif
{
if ( Options & DNS_QUERY_CACHE_ONLY )
{
status = ERROR_INVALID_PARAMETER;
goto Done;
}
goto InProcessQuery;
}
//
// querying through cache
// - get cluster-filtering info
//
if ( g_IsServer )
{
ENVAR_DWORD_INFO filterInfo;
Reg_ReadDwordEnvar(
RegIdFilterClusterIp,
&filterInfo );
if ( filterInfo.fFound && filterInfo.Value )
{
Options |= DNSP_QUERY_FILTER_CLUSTER;
}
}
rpcStatus = NO_ERROR;
RpcTryExcept
{
status = R_ResolverQuery(
NULL,
(PWSTR) pwsName,
wType,
Options,
&prpcRecord );
}
RpcExcept( DNS_RPC_EXCEPTION_FILTER )
{
rpcStatus = RpcExceptionCode();
}
RpcEndExcept
//
// cache unavailable
// - bail if just querying cache
// - otherwise query direct
if ( rpcStatus != NO_ERROR )
{
DNSDBG( TRACE, (
"DnsQuery_W() RPC failed status = %d\n",
rpcStatus ));
goto InProcessQuery;
}
if ( status == DNS_ERROR_NO_TCPIP )
{
DNSDBG( TRACE, (
"DnsQuery_W() NO_TCPIP error!\n"
"\tassume resolver security problem -- query in process!\n"
));
RTL_ASSERT( !prpcRecord );
goto InProcessQuery;
}
//
// return records
// - screen out empty-auth responses
//
// DCR_FIX1: cache should convert and return NO_RECORDS response
// directly (no need to do this here)
//
// DCR: UNLESS we allow return of these records
//
if ( prpcRecord )
{
FixupNameOwnerPointers( prpcRecord );
if ( IsEmptyDnsResponseFromResolver( prpcRecord ) )
{
Dns_RecordListFree( prpcRecord );
prpcRecord = NULL;
if ( status == NO_ERROR )
{
status = DNS_INFO_NO_RECORDS;
}
}
*ppResultSet = prpcRecord;
}
RTL_ASSERT( status!=NO_ERROR || prpcRecord );
goto Done;
//
// query directly -- either skipping cache or it's unavailable
//
InProcessQuery:
DNSDBG( TRACE, (
"DnsQuery_W() -- doing in process query\n"
"\tpname = %S\n"
"\ttype = %d\n",
pwsName,
wType ));
//
// load query blob
//
// DCR: set some sort of "want message buffer" flag if ppMessageResponse
// exists
//
pblob = ALLOCATE_HEAP_ZERO( sizeof(*pblob) );
if ( !pblob )
{
status = DNS_ERROR_NO_MEMORY;
goto Done;
}
pblob->pNameOrig = (PWSTR) pwsName;
pblob->wType = wType;
pblob->Flags = Options | DNSQUERY_UNICODE_OUT;
pblob->pDnsServers = pDnsServers;
//
// query
// - then set OUT params
status = Query_InProcess( pblob );
if ( ppResultSet )
{
*ppResultSet = pblob->pRecords;
RTL_ASSERT( status!=NO_ERROR || *ppResultSet );
}
else
{
Dns_RecordListFree( pblob->pRecords );
}
if ( ppMessageResponse )
{
*ppMessageResponse = pblob->pRecvMsg;
}
FREE_HEAP( pblob );
Done:
// sanity check
if ( status==NO_ERROR &&
ppResultSet &&
!*ppResultSet )
{
RTL_ASSERT( FALSE );
status = DNS_INFO_NO_RECORDS;
}
if ( pnameLocal )
{
FREE_HEAP( pnameLocal );
}
DNSDBG( TRACE, (
"Leave DnsQuery_W()\n"
"\tstatus = %d\n"
"\tresult set = %p\n\n\n",
status,
*ppResultSet ));
return( status );
}
//
// DnsQueryEx() routines
//
DNS_STATUS
WINAPI
ShimDnsQueryEx(
IN OUT PDNS_QUERY_INFO pQueryInfo
)
/*++
Routine Description:
Query DNS -- shim for main SDK query routine.
Arguments:
pQueryInfo -- blob describing query
Return Value:
ERROR_SUCCESS if successful query.
Error code on failure.
--*/
{
PDNS_RECORD prrResult;
WORD type = pQueryInfo->Type;
DNS_STATUS status;
DNS_LIST listAnswer;
DNS_LIST listAlias;
DNS_LIST listAdditional;
DNS_LIST listAuthority;
DNSDBG( TRACE, ( "ShimDnsQueryEx()\n" ));
//
// DCR: temp hack is to pass this to DNSQuery
//
status = DnsQuery_W(
(PWSTR) pQueryInfo->pName,
type,
pQueryInfo->Flags,
pQueryInfo->pDnsServers,
& prrResult,
NULL );
pQueryInfo->Status = status;
//
// cut result records appropriately
//
pQueryInfo->pAnswerRecords = NULL;
pQueryInfo->pAliasRecords = NULL;
pQueryInfo->pAdditionalRecords = NULL;
pQueryInfo->pAuthorityRecords = NULL;
if ( prrResult )
{
PDNS_RECORD prr;
PDNS_RECORD pnextRR;
DNS_LIST_STRUCT_INIT( listAnswer );
DNS_LIST_STRUCT_INIT( listAlias );
DNS_LIST_STRUCT_INIT( listAdditional );
DNS_LIST_STRUCT_INIT( listAuthority );
//
// break list into section specific lists
// - section 0 for hostfile records
// - note, this does pull RR sets apart, but
// they, being in same section, should immediately
// be rejoined
//
pnextRR = prrResult;
while ( prr = pnextRR )
{
pnextRR = prr->pNext;
prr->pNext = NULL;
if ( prr->Flags.S.Section == 0 ||
prr->Flags.S.Section == DNSREC_ANSWER )
{
if ( prr->wType == DNS_TYPE_CNAME &&
type != DNS_TYPE_CNAME )
{
DNS_LIST_STRUCT_ADD( listAlias, prr );
continue;
}
else
{
DNS_LIST_STRUCT_ADD( listAnswer, prr );
continue;
}
}
else if ( prr->Flags.S.Section == DNSREC_ADDITIONAL )
{
DNS_LIST_STRUCT_ADD( listAdditional, prr );
continue;
}
else
{
DNS_LIST_STRUCT_ADD( listAuthority, prr );
continue;
}
}
// pack stuff back into blob
pQueryInfo->pAnswerRecords = listAnswer.pFirst;
pQueryInfo->pAliasRecords = listAlias.pFirst;
pQueryInfo->pAuthorityRecords = listAuthority.pFirst;
pQueryInfo->pAdditionalRecords = listAdditional.pFirst;
//pQueryInfo->pSigRecords = listSig.pFirst;
//
// convert result records back to ANSI (or UTF8)
// - convert each result set
// - then paste back into query blob
//
// DCR_FIX0: handle issue of failure on conversion
//
if ( pQueryInfo->CharSet != DnsCharSetUnicode )
{
PDNS_RECORD prr;
PDNS_RECORD * prrSetPtr;
prrSetPtr = & pQueryInfo->pAnswerRecords;
for ( prrSetPtr = & pQueryInfo->pAnswerRecords;
prrSetPtr <= & pQueryInfo->pAdditionalRecords;
prrSetPtr++ )
{
prr = *prrSetPtr;
*prrSetPtr = Dns_RecordSetCopyEx(
prr,
DnsCharSetUnicode,
pQueryInfo->CharSet
);
Dns_RecordListFree( prr );
}
}
}
//
// replace name for originally narrow queries
//
if ( pQueryInfo->CharSet != DnsCharSetUnicode )
{
ASSERT( pQueryInfo->CharSet != 0 );
ASSERT( pQueryInfo->pReservedName != NULL );
FREE_HEAP( pQueryInfo->pName );
pQueryInfo->pName = (LPTSTR) pQueryInfo->pReservedName;
pQueryInfo->pReservedName = NULL;
}
//
// indicate return if async
//
if ( pQueryInfo->hEvent )
{
SetEvent( pQueryInfo->hEvent );
}
return( status );
}
DNS_STATUS
WINAPI
CombinedQueryEx(
IN OUT PDNS_QUERY_INFO pQueryInfo,
IN DNS_CHARSET CharSet
)
/*++
Routine Description:
Convert narrow to wide query.
This routine simple avoids duplicate code in ANSI
and UTF8 query routines.
Arguments:
pQueryInfo -- query info blob
CharSet -- char set of original query
Return Value:
ERROR_SUCCESS on success.
DNS RCODE error on query with RCODE
DNS_INFO_NO_RECORDS on no records response.
ErrorCode on failure.
--*/
{
DNS_STATUS status = NO_ERROR;
PWSTR pwideName = NULL;
HANDLE hthread;
DWORD threadId;
DNSDBG( TRACE, (
"CombinedQueryEx( %S%s, type=%d, flag=%08x, event=%p )\n",
PRINT_STRING_WIDE_CHARSET( pQueryInfo->pName, CharSet ),
PRINT_STRING_ANSI_CHARSET( pQueryInfo->pName, CharSet ),
pQueryInfo->Type,
pQueryInfo->Flags,
pQueryInfo->hEvent ));
//
// set CharSet
//
pQueryInfo->CharSet = CharSet;
if ( CharSet == DnsCharSetUnicode )
{
pQueryInfo->pReservedName = 0;
}
//
// if narrow name
// - allocate wide name copy
// - swap in wide name and make query wide
//
// DCR: allow NULL name? for local machine name?
//
else if ( CharSet == DnsCharSetAnsi ||
CharSet == DnsCharSetUtf8 )
{
WORD nameLength;
PSTR pnameNarrow;
pnameNarrow = pQueryInfo->pName;
if ( !pnameNarrow )
{
return ERROR_INVALID_PARAMETER;
}
nameLength = (WORD) strlen( pnameNarrow );
pwideName = ALLOCATE_HEAP( (nameLength + 1) * sizeof(WCHAR) );
if ( !pwideName )
{
return DNS_ERROR_NO_MEMORY;
}
if ( !Dns_NameCopy(
(PSTR) pwideName,
NULL,
pnameNarrow,
nameLength,
CharSet,
DnsCharSetUnicode ) )
{
status = ERROR_INVALID_NAME;
goto Failed;
}
pQueryInfo->pName = (LPTSTR) pwideName;
pQueryInfo->pReservedName = pnameNarrow;
}
//
// async?
// - if event exists we are async
// - spin up thread and call it
//
if ( pQueryInfo->hEvent )
{
hthread = CreateThread(
NULL, // no security
0, // default stack
ShimDnsQueryEx,
pQueryInfo, // param
0, // run immediately
& threadId
);
if ( !hthread )
{
DNS_STATUS status = GetLastError();
DNSDBG( ANY, (
"Failed to create thread = %d\n",
status ));
if ( status == ERROR_SUCCESS )
{
status = DNS_ERROR_NO_MEMORY;
}
goto Failed;
}
CloseHandle( hthread );
return( ERROR_IO_PENDING );
}
//
// otherwise make direct async call
//
return ShimDnsQueryEx( pQueryInfo );
Failed:
FREE_HEAP( pwideName );
return( status );
}
DNS_STATUS
WINAPI
DnsQueryExW(
IN OUT PDNS_QUERY_INFO pQueryInfo
)
/*++
Routine Description:
Query DNS -- main SDK query routine.
Arguments:
pQueryInfo -- blob describing query
Return Value:
ERROR_SUCCESS if successful query.
ERROR_IO_PENDING if successful async start.
Error code on failure.
--*/
{
DNSDBG( TRACE, (
"DnsQueryExW( %S, type=%d, flag=%08x, event=%p )\n",
pQueryInfo->pName,
pQueryInfo->Type,
pQueryInfo->Flags,
pQueryInfo->hEvent ));
return CombinedQueryEx( pQueryInfo, DnsCharSetUnicode );
}
DNS_STATUS
WINAPI
DnsQueryExA(
IN OUT PDNS_QUERY_INFO pQueryInfo
)
/*++
Routine Description:
Query DNS -- main SDK query routine.
Arguments:
pQueryInfo -- blob describing query
Return Value:
ERROR_SUCCESS if successful query.
ERROR_IO_PENDING if successful async start.
Error code on failure.
--*/
{
DNSDBG( TRACE, (
"DnsQueryExA( %s, type=%d, flag=%08x, event=%p )\n",
pQueryInfo->pName,
pQueryInfo->Type,
pQueryInfo->Flags,
pQueryInfo->hEvent ));
return CombinedQueryEx( pQueryInfo, DnsCharSetAnsi );
}
DNS_STATUS
WINAPI
DnsQueryExUTF8(
IN OUT PDNS_QUERY_INFO pQueryInfo
)
/*++
Routine Description:
Query DNS -- main SDK query routine.
Arguments:
pQueryInfo -- blob describing query
Return Value:
ERROR_SUCCESS if successful query.
ERROR_IO_PENDING if successful async start.
Error code on failure.
--*/
{
DNSDBG( TRACE, (
"DnsQueryExUTF8( %s, type=%d, flag=%08x, event=%p )\n",
pQueryInfo->pName,
pQueryInfo->Type,
pQueryInfo->Flags,
pQueryInfo->hEvent ));
return CombinedQueryEx( pQueryInfo, DnsCharSetUtf8 );
}
//
// Name collision API
//
// DCR_QUESTION: name collision -- is there any point to this?
//
DNS_STATUS
WINAPI
DnsCheckNameCollision_UTF8(
IN PCSTR pszName,
IN DWORD Options
)
/*++
Routine Description:
None.
Arguments:
None.
Return Value:
None.
--*/
{
DNS_STATUS status = NO_ERROR;
PDNS_RECORD prrList = NULL;
PDNS_RECORD prr = NULL;
DWORD iter;
BOOL fmatch = FALSE;
WORD wtype = DNS_TYPE_A;
if ( !pszName )
{
return ERROR_INVALID_PARAMETER;
}
if ( Options & DNS_CHECK_AGAINST_HOST_ANY )
{
wtype = DNS_TYPE_ANY;
}
status = DnsQuery_UTF8( pszName,
wtype,
DNS_QUERY_BYPASS_CACHE,
NULL,
&prrList,
NULL );
if ( status == DNS_ERROR_RCODE_NAME_ERROR ||
status == DNS_INFO_NO_RECORDS )
{
Dns_RecordListFree( prrList );
return NO_ERROR;
}
if ( status == NO_ERROR &&
Options == DNS_CHECK_AGAINST_HOST_ANY )
{
Dns_RecordListFree( prrList );
return DNS_ERROR_RCODE_YXRRSET;
}
if ( status == NO_ERROR &&
Options == DNS_CHECK_AGAINST_HOST_DOMAIN_NAME )
{
char TestName[DNS_MAX_NAME_LENGTH * 2];
PSTR pszHostName = Reg_GetHostName( DnsCharSetUtf8 );
PSTR pszPrimaryDomain = Reg_GetPrimaryDomainName( DnsCharSetUtf8 );
fmatch = TRUE;
strcpy( TestName, pszHostName );
if ( pszPrimaryDomain )
{
strcat( TestName, "." );
strcat( TestName, pszPrimaryDomain );
}
if ( Dns_NameCompare_UTF8( pszHostName, (PSTR)pszName ) )
{
fmatch = TRUE;
}
if ( !fmatch &&
pszPrimaryDomain &&
Dns_NameCompare_UTF8( TestName, (PSTR)pszName ) )
{
fmatch = TRUE;
}
if ( !fmatch )
{
PDNS_NETINFO pNetInfo = GetNetworkInfo();
if ( pNetInfo )
{
for ( iter = 0; iter < pNetInfo->AdapterCount; iter++ )
{
PSTR pszDomain = pNetInfo->AdapterArray[iter]->
pszAdapterDomain;
if ( pszDomain )
{
strcpy( TestName, pszHostName );
strcat( TestName, "." );
strcat( TestName, pszDomain );
if ( Dns_NameCompare_UTF8( TestName, (PSTR)pszName ) )
fmatch = TRUE;
}
}
}
NetInfo_Free( pNetInfo );
}
FREE_HEAP( pszHostName );
FREE_HEAP( pszPrimaryDomain );
if ( fmatch )
{
Dns_RecordListFree( prrList );
return DNS_ERROR_RCODE_YXRRSET;
}
}
if ( status == NO_ERROR )
{
PDNS_ADDRESS_INFO pAddressInfo = NULL;
DWORD Count = DnsGetIpAddressInfoList( &pAddressInfo );
if ( Count == 0 )
{
Dns_RecordListFree( prrList );
return DNS_ERROR_RCODE_YXRRSET;
}
prr = prrList;
while ( prr )
{
fmatch = FALSE;
if ( prr->Flags.S.Section != DNSREC_ANSWER )
{
prr = prr->pNext;
continue;
}
if ( prr->wType == DNS_TYPE_CNAME )
{
FREE_HEAP( pAddressInfo );
Dns_RecordListFree( prrList );
return DNS_ERROR_RCODE_YXRRSET;
}
for ( iter = 0; iter < Count; iter++ )
{
if ( prr->Data.A.IpAddress == pAddressInfo[iter].ipAddress )
{
fmatch = TRUE;
}
}
if ( !fmatch )
{
FREE_HEAP( pAddressInfo );
Dns_RecordListFree( prrList );
return DNS_ERROR_RCODE_YXRRSET;
}
prr = prr->pNext;
}
FREE_HEAP( pAddressInfo );
Dns_RecordListFree( prrList );
return NO_ERROR;
}
return status;
}
DNS_STATUS
WINAPI
DnsCheckNameCollision_A(
IN PCSTR pszName,
IN DWORD Options
)
/*++
Routine Description:
None.
Arguments:
None.
Return Value:
None.
--*/
{
PSTR pUtf8Name = NULL;
DNS_STATUS status = NO_ERROR;
//
// DCR_CLEANUP: fix unnecessary alloc
// DCR_PERF: eliminate alloc
//
if ( !pszName )
{
return ERROR_INVALID_PARAMETER;
}
pUtf8Name = Dns_NameCopyAllocate(
(PSTR) pszName,
0,
DnsCharSetAnsi,
DnsCharSetUtf8 );
if ( !pUtf8Name )
{
return DNS_ERROR_NO_MEMORY;
}
status = DnsCheckNameCollision_UTF8( pUtf8Name, Options );
FREE_HEAP( pUtf8Name );
return status;
}
DNS_STATUS
WINAPI
DnsCheckNameCollision_W(
IN PCWSTR pszName,
IN DWORD Options
)
/*++
Routine Description:
None.
Arguments:
None.
Return Value:
None.
--*/
{
//
// DCR_CLEANUP: fix unnecessary alloc
// DCR_PERF: eliminate alloc
//
DNS_STATUS status = NO_ERROR;
PSTR lpTempName = NULL;
WORD nameLength;
if ( !pszName )
{
return ERROR_INVALID_PARAMETER;
}
nameLength = (WORD)wcslen( pszName );
lpTempName = ALLOCATE_HEAP( (nameLength + 1) * sizeof(WCHAR) );
if ( lpTempName == NULL )
{
return DNS_ERROR_NO_MEMORY;
}
Dns_NameCopy( lpTempName,
NULL,
(PSTR) pszName,
0,
DnsCharSetUnicode,
DnsCharSetUtf8 );
status = DnsCheckNameCollision_UTF8( lpTempName, Options );
FREE_HEAP( lpTempName );
return status;
}
//
// Roll your own query utilities
//
BOOL
WINAPI
DnsWriteQuestionToBuffer_W(
IN OUT PDNS_MESSAGE_BUFFER pDnsBuffer,
IN OUT LPDWORD pdwBufferSize,
IN PWSTR pszName,
IN WORD wType,
IN WORD Xid,
IN BOOL fRecursionDesired
)
/*++
Routine Description:
None.
Arguments:
None.
Return Value:
None.
--*/
{
//
// DCR_CLEANUP: duplicate code with routine below ... surprise!
// - eliminate duplicate
// - probably can just pick up library routine
//
PCHAR pch;
PCHAR pbufferEnd = NULL;
if ( *pdwBufferSize >= DNS_MAX_UDP_PACKET_BUFFER_LENGTH )
{
pbufferEnd = (PCHAR)pDnsBuffer + *pdwBufferSize;
// clear header
RtlZeroMemory( pDnsBuffer, sizeof(DNS_HEADER) );
// set for rewriting
pch = pDnsBuffer->MessageBody;
// write question name
pch = Dns_WriteDottedNameToPacket(
pch,
pbufferEnd,
(PCHAR) pszName,
NULL,
0,
TRUE );
if ( !pch )
{
return FALSE;
}
// write question structure
*(UNALIGNED WORD *) pch = htons( wType );
pch += sizeof(WORD);
*(UNALIGNED WORD *) pch = DNS_RCLASS_INTERNET;
pch += sizeof(WORD);
// set question RR section count
pDnsBuffer->MessageHead.QuestionCount = htons( 1 );
pDnsBuffer->MessageHead.RecursionDesired = (BOOLEAN)fRecursionDesired;
pDnsBuffer->MessageHead.Xid = htons( Xid );
*pdwBufferSize = (DWORD)(pch - (PCHAR)pDnsBuffer);
return TRUE;
}
else
{
*pdwBufferSize = DNS_MAX_UDP_PACKET_BUFFER_LENGTH;
return FALSE;
}
}
BOOL
WINAPI
DnsWriteQuestionToBuffer_UTF8(
IN OUT PDNS_MESSAGE_BUFFER pDnsBuffer,
IN OUT PDWORD pdwBufferSize,
IN PSTR pszName,
IN WORD wType,
IN WORD Xid,
IN BOOL fRecursionDesired
)
/*++
Routine Description:
None.
Arguments:
None.
Return Value:
None.
--*/
{
PCHAR pch;
PCHAR pbufferEnd = NULL;
if ( *pdwBufferSize >= DNS_MAX_UDP_PACKET_BUFFER_LENGTH )
{
pbufferEnd = (PCHAR)pDnsBuffer + *pdwBufferSize;
// clear header
RtlZeroMemory( pDnsBuffer, sizeof(DNS_HEADER) );
// set for rewriting
pch = pDnsBuffer->MessageBody;
// write question name
pch = Dns_WriteDottedNameToPacket(
pch,
pbufferEnd,
pszName,
NULL,
0,
FALSE );
if ( !pch )
{
return FALSE;
}
// write question structure
*(UNALIGNED WORD *) pch = htons( wType );
pch += sizeof(WORD);
*(UNALIGNED WORD *) pch = DNS_RCLASS_INTERNET;
pch += sizeof(WORD);
// set question RR section count
pDnsBuffer->MessageHead.QuestionCount = htons( 1 );
pDnsBuffer->MessageHead.RecursionDesired = (BOOLEAN)fRecursionDesired;
pDnsBuffer->MessageHead.Xid = htons( Xid );
*pdwBufferSize = (DWORD)(pch - (PCHAR)pDnsBuffer);
return TRUE;
}
else
{
*pdwBufferSize = DNS_MAX_UDP_PACKET_BUFFER_LENGTH;
return FALSE;
}
}
//
// Record list to\from results
//
VOID
CombineRecordsInBlob(
IN PDNS_RESULTS pResults,
OUT PDNS_RECORD * ppRecords
)
/*++
Routine Description:
Query DNS -- shim for main SDK query routine.
Arguments:
pQueryInfo -- blob describing query
Return Value:
ERROR_SUCCESS if successful query.
Error code on failure.
--*/
{
PDNS_RECORD prr;
DNSDBG( TRACE, ( "CombineRecordsInBlob()\n" ));
//
// combine records back into one list
//
// note, working backwards so only touch records once
//
prr = Dns_RecordListAppend(
pResults->pAuthorityRecords,
pResults->pAdditionalRecords
);
prr = Dns_RecordListAppend(
pResults->pAnswerRecords,
prr
);
prr = Dns_RecordListAppend(
pResults->pAliasRecords,
prr
);
*ppRecords = prr;
}
VOID
BreakRecordsIntoBlob(
OUT PDNS_RESULTS pResults,
IN PDNS_RECORD pRecords,
IN WORD wType
)
/*++
Routine Description:
Break single record list into results pblob->
Arguments:
pResults -- results to fill in
pRecords -- record list
Return Value:
None
--*/
{
PDNS_RECORD prr;
PDNS_RECORD pnextRR;
DNS_LIST listAnswer;
DNS_LIST listAlias;
DNS_LIST listAdditional;
DNS_LIST listAuthority;
DNSDBG( TRACE, ( "BreakRecordsIntoBlob()\n" ));
//
// clear blob
//
RtlZeroMemory(
pResults,
sizeof(*pResults) );
//
// init building lists
//
DNS_LIST_STRUCT_INIT( listAnswer );
DNS_LIST_STRUCT_INIT( listAlias );
DNS_LIST_STRUCT_INIT( listAdditional );
DNS_LIST_STRUCT_INIT( listAuthority );
//
// break list into section specific lists
// - note, this does pull RR sets apart, but
// they, being in same section, should immediately
// be rejoined
//
// - note, hostfile records made have section=0
// this is no longer the case but preserve until
// know this is solid and determine what section==0
// means
//
pnextRR = pRecords;
while ( prr = pnextRR )
{
pnextRR = prr->pNext;
prr->pNext = NULL;
if ( prr->Flags.S.Section == 0 ||
prr->Flags.S.Section == DNSREC_ANSWER )
{
if ( prr->wType == DNS_TYPE_CNAME &&
wType != DNS_TYPE_CNAME )
{
DNS_LIST_STRUCT_ADD( listAlias, prr );
continue;
}
else
{
DNS_LIST_STRUCT_ADD( listAnswer, prr );
continue;
}
}
else if ( prr->Flags.S.Section == DNSREC_ADDITIONAL )
{
DNS_LIST_STRUCT_ADD( listAdditional, prr );
continue;
}
else
{
DNS_LIST_STRUCT_ADD( listAuthority, prr );
continue;
}
}
// pack stuff into blob
pResults->pAnswerRecords = listAnswer.pFirst;
pResults->pAliasRecords = listAlias.pFirst;
pResults->pAuthorityRecords = listAuthority.pFirst;
pResults->pAdditionalRecords = listAdditional.pFirst;
}
//
// Random discontinued
//
#if 0
IP_ADDRESS
findHostIpInRecordList(
IN PDNS_RECORD pRecord,
IN PDNS_NAME pszHostName
)
/*++
Routine Description:
Find IP for hostname, if its A record is in list.
Arguments:
pRecord - incoming RR set
pszHostName - hostname to find
Return Value:
IP address matching hostname, if A record for hostname found.
Zero if not found.
--*/
{
//
// DCR: find best A record for name
// currently only finds first; this is harmless but in
// disjoint net situation would need sorted to find best
//
while ( pRecord )
{
if ( pRecord->wType == DNS_TYPE_A &&
Dns_NameCompare(
pRecord->pName,
pszHostName ) )
{
return( pRecord->Data.A.IpAddress );
}
pRecord = pRecord->pNext;
}
return( 0 );
}
#endif
//
// End query.c
//
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