diff --git a/reactos/sdk/include/psdk/windns.h b/reactos/sdk/include/psdk/windns.h
index 742d93b7908..abe7815880f 100644
--- a/reactos/sdk/include/psdk/windns.h
+++ b/reactos/sdk/include/psdk/windns.h
@@ -104,6 +104,8 @@ typedef _Return_type_success_(return == 0) DWORD DNS_STATUS;
 
 #define DNS_ATMA_MAX_ADDR_LENGTH 20
 
+#define DNS_ADDR_MAX_SOCKADDR_LENGTH 32
+
 typedef enum _DNS_CHARSET {
   DnsCharSetUnknown,
   DnsCharSetUnicode,
@@ -165,6 +167,36 @@ typedef struct {
 
 #pragma pack(push, 1)
 
+typedef struct _DnsAddr
+{
+  CHAR MaxSa[DNS_ADDR_MAX_SOCKADDR_LENGTH];
+#if defined(__midl) || defined(__WIDL__)
+  DWORD DnsAddrUserDword[8];
+#else
+  union {
+    DWORD DnsAddrUserDword[8];
+  } Data;
+#endif
+} DNS_ADDR, *PDNS_ADDR;
+
+typedef struct _DnsAddrArray
+{
+  DWORD MaxCount;
+  DWORD AddrCount;
+  DWORD Tag;
+  WORD  Family;
+  WORD  WordReserved;
+  DWORD Flags;
+  DWORD MatchFlag;
+  DWORD Reserved1;
+  DWORD Reserved2;
+#if defined(__midl) || defined(__WIDL__)
+  [size_is(AddrCount)] DNS_ADDR AddrArray[];
+#else
+  DNS_ADDR AddrArray[1];
+#endif
+} DNS_ADDR_ARRAY, *PDNS_ADDR_ARRAY;
+
 typedef struct _DNS_HEADER {
   WORD Xid;
   BYTE RecursionDesired:1;
@@ -447,6 +479,88 @@ typedef struct {
   BYTE BitMask[1];
 } DNS_WKS_DATA, *PDNS_WKS_DATA;
 
+typedef struct {
+  WORD wKeyTag;
+  BYTE chAlgorithm;
+  BYTE chDigestType;
+  WORD wDigestLength;
+  WORD wPad;
+  BYTE Digest[1];
+} DNS_DS_DATA;
+
+typedef struct {
+  LPWSTR pNextDomainName;    
+  WORD wTypeBitMapsLength;
+  WORD wPad;
+  BYTE TypeBitMaps[1];
+} DNS_NSEC_DATAW;
+
+typedef struct {
+  WORD wFlags;
+  BYTE chProtocol;
+  BYTE chAlgorithm;
+  WORD wKeyLength;
+  WORD wPad;
+  BYTE Key[1];
+} DNS_DNSKEY_DATA;
+
+typedef struct {
+  WORD wDataLength;
+  WORD wPad;
+  BYTE Data[1];
+} DNS_OPT_DATA;
+
+typedef struct {
+  WORD wTypeCovered;
+  BYTE chAlgorithm;
+  BYTE chLabelCount;
+  DWORD dwOriginalTtl;
+  DWORD dwExpiration;
+  DWORD dwTimeSigned;
+  WORD wKeyTag;
+  WORD Pad;
+  LPWSTR pNameSigner;
+  BYTE Signature[1];
+} DNS_RRSIG_DATAW;
+
+#if defined(__midl) || defined(__WIDL__)
+typedef [switch_type(unsigned short )] union DNS_DATAW {
+  [case(1)] DNS_A_DATA A;
+  [case(6)] DNS_SOA_DATAW SOA;
+  [case(12)] DNS_PTR_DATAW PTR;
+  [case(2)] DNS_PTR_DATAW NS;
+  [case(5)] DNS_PTR_DATAW CNAME;
+  [case(7)] DNS_PTR_DATAW MB;
+  [case(3)] DNS_PTR_DATAW MD;
+  [case(4)] DNS_PTR_DATAW MF;
+  [case(8)] DNS_PTR_DATAW MG;
+  [case(9)] DNS_PTR_DATAW MR;
+  [case(14)] DNS_MINFO_DATAW MINFO;
+  [case(17)] DNS_MINFO_DATAW RP;
+  [case(15)] DNS_MX_DATAW MX;
+  [case(18)] DNS_MX_DATAW AFSDB;
+  [case(21)] DNS_MX_DATAW RT;
+  [case(28)] DNS_AAAA_DATA AAAA;
+  [case(33)] DNS_SRV_DATAW SRV;
+  [case(34)] DNS_ATMA_DATA ATMA;
+  [case(43)] DNS_DS_DATA DS;
+  [case(46)] DNS_RRSIG_DATAW RRSIG;
+  [case(47)] DNS_NSEC_DATAW NSEC;
+  [case(48)] DNS_DNSKEY_DATA DNSKEY;
+  [case(41)] DNS_OPT_DATA OPT;
+} DNS_DATAW;
+
+typedef struct _DnsRecordW {
+  [unique]struct _DnsRecordW *pNext;
+  [unique][string] LPWSTR  pName;
+  WORD wType;
+  WORD wDataLength;
+  DWORD Flags;
+  DWORD dwTtl;
+  DWORD dwReserved;
+  [switch_is(wType)] DNS_DATAW Data;
+} _DnsRecordW;    
+#else
 typedef struct _DnsRecordA {
   struct _DnsRecordA* pNext;
   LPSTR pName;
@@ -521,6 +635,8 @@ typedef struct _DnsRecordW {
 #define PDNS_RECORD PDNS_RECORDA
 #endif
 
+#endif
+
 typedef struct _DnsRRSet {
   PDNS_RECORD pFirstRR;
   PDNS_RECORD pLastRR;
@@ -547,6 +663,9 @@ typedef struct _DnsRRSet {
     _prrset->pLastRR->pNext = NULL;  \
 }
 
+#ifndef __WIDL__
+// HACK
+
 DNS_STATUS
 WINAPI
 DnsAcquireContextHandle_A(
@@ -608,14 +727,14 @@ DnsModifyRecordsInSet_UTF8(
 BOOL
 WINAPI
 DnsNameCompare_A(
-  _In_ PCSTR,
-  _In_ PCSTR);
+  _In_ PCSTR pszName1,
+  _In_ PCSTR pszName2);
 
 BOOL
 WINAPI
 DnsNameCompare_W(
-  _In_ PCWSTR,
-  _In_ PCWSTR);
+  _In_ PCWSTR pszwName1,
+  _In_ PCWSTR pszwName2);
 
 DNS_STATUS
 WINAPI
@@ -765,6 +884,7 @@ DnsWriteQuestionToBuffer_UTF8(
   _In_ WORD wType,
   _In_ WORD Xid,
   _In_ BOOL fRecursionDesired);
+#endif
 
 #ifdef UNICODE
 
diff --git a/reactos/sdk/include/reactos/idl/dnsrslvr.idl b/reactos/sdk/include/reactos/idl/dnsrslvr.idl
new file mode 100644
index 00000000000..f11fc55a241
--- /dev/null
+++ b/reactos/sdk/include/reactos/idl/dnsrslvr.idl
@@ -0,0 +1,59 @@
+/*
+ * DNS Resolver Service interface definition
+ */
+
+#include <ms-dtyp.idl>
+#include <sal.h>
+#include <windns.h>
+
+typedef [handle, string] LPWSTR DNSRSLVR_HANDLE;
+
+[
+    uuid(45776b01-5956-4485-9f80-f428f7d60129),
+    version(2.0),
+    pointer_default(unique)
+#ifndef __midl
+    ,explicit_handle
+#endif
+] 
+
+interface DnsResolver
+{
+    /* Function: 0x00 */
+    /* CRrReadCache */
+
+    /* Function: 0x01 */
+    /* CRrReadCacheEntry */
+
+    /* Function: 0x02 */
+    /* CRrGetHashTableStats */
+
+    /* Function: 0x03 */
+    /* R_ResolverGetConfig */
+
+    /* Function: 0x04 */
+    DWORD R_ResolverFlushCache(
+        [in][unique][string] DNSRSLVR_HANDLE pwszServerName);
+
+    /* Function: 0x05 */
+    /* R_ResolverFlushCacheEntry */
+
+    /* Function: 0x06 */
+    /* R_ResolverRegisterCluster */
+
+    /* Function: 0x07 */
+    DWORD R_ResolverQuery(
+        [in][unique][string] DNSRSLVR_HANDLE pwszServerName,
+        [in][unique][string] LPCWSTR pwsName, 
+        [in] WORD wType, 
+        [in] DWORD Flags, 
+        [in][out] DWORD *dwRecords, 
+        [out][ref] _DnsRecordW** ppResultRecords);
+
+    /* Function: 0x08 */
+    /* R_ResolverEnumCache */
+
+    /* Function: 0x09 */
+    /* R_ResolverPoke */
+
+}