diff --git a/dlls/crypt32/crypt32.spec b/dlls/crypt32/crypt32.spec
index 5a54d685fb7..1e09b8e0d6c 100644
--- a/dlls/crypt32/crypt32.spec
+++ b/dlls/crypt32/crypt32.spec
@@ -137,10 +137,10 @@ name crypt32
 @ stub CryptRegisterDefaultOIDFunction
 @ stub CryptRegisterOIDFunction
 @ stub CryptRegisterOIDInfo
-@ stub CryptSIPAddProvider
-@ stub CryptSIPLoad
-@ stub CryptSIPRemoveProvider
-@ stub CryptSIPRetrieveSubjectGuid
+@ stdcall CryptSIPAddProvider(ptr) CryptSIPAddProvider
+@ stdcall CryptSIPLoad(ptr long ptr) CryptSIPLoad
+@ stdcall CryptSIPRemoveProvider(ptr) CryptSIPRemoveProvider
+@ stdcall CryptSIPRetrieveSubjectGuid(wstr long ptr) CryptSIPRetrieveSubjectGuid
 @ stub CryptSetAsyncParam
 @ stub CryptSetOIDFunctionValue
 @ stub CryptSetProviderU
diff --git a/dlls/crypt32/main.c b/dlls/crypt32/main.c
index 78d00e770ec..bb232beb6fa 100644
--- a/dlls/crypt32/main.c
+++ b/dlls/crypt32/main.c
@@ -18,6 +18,11 @@
 
 #include "config.h"
 #include "winbase.h"
+#include "wincrypt.h"
+/* #include "mssip.h" */
+
+typedef struct SIP_DISPATCH_INFO_ SIP_DISPATCH_INFO, *LPSIP_DISPATCH_INFO;
+typedef struct SIP_ADD_NEWPROVIDER_ SIP_ADD_NEWPROVIDER, *PSIP_ADD_NEWPROVIDER;
 
 /* this function is called by Internet Explorer when it is about to verify a downloaded component */
 BOOL WINAPI I_CryptCreateLruCache(DWORD x, DWORD y)
@@ -40,3 +45,25 @@ BOOL WINAPI I_CryptFreeLruCache(DWORD x)
 {
     return FALSE;
 }
+
+BOOL WINAPI CryptSIPRemoveProvider(GUID *pgProv)
+{
+    return FALSE;
+}
+
+BOOL WINAPI CryptSIPAddProvider(SIP_ADD_NEWPROVIDER *psNewProv)
+{
+    return FALSE;
+}
+
+BOOL WINAPI CryptSIPRetrieveSubjectGuid
+      (LPCWSTR FileName, OPTIONAL HANDLE hFileIn, GUID *pgSubject)
+{
+    return FALSE;
+}
+
+BOOL WINAPI CryptSIPLoad
+       (const GUID *pgSubject, DWORD dwFlags, SIP_DISPATCH_INFO *pSipDispatch)
+{
+    return FALSE;
+}