diff --git a/dlls/bcrypt/bcrypt.spec b/dlls/bcrypt/bcrypt.spec
index 9ecd21d767c..f00f55c306a 100644
--- a/dlls/bcrypt/bcrypt.spec
+++ b/dlls/bcrypt/bcrypt.spec
@@ -1,5 +1,5 @@
-@ stub BCryptAddContextFunction
-@ stub BCryptAddContextFunctionProvider
+@ stdcall BCryptAddContextFunction(long wstr long wstr long)
+@ stdcall BCryptAddContextFunctionProvider(long wstr long wstr wstr long)
 @ stdcall BCryptCloseAlgorithmProvider(ptr long)
 @ stub BCryptConfigureContext
 @ stub BCryptConfigureContextFunction
@@ -39,9 +39,9 @@
 @ stub BCryptQueryContextFunctionProperty
 @ stub BCryptQueryProviderRegistration
 @ stub BCryptRegisterConfigChangeNotify
-@ stub BCryptRegisterProvider
-@ stub BCryptRemoveContextFunction
-@ stub BCryptRemoveContextFunctionProvider
+@ stdcall BCryptRegisterProvider(wstr long ptr)
+@ stdcall BCryptRemoveContextFunction(long wstr long wstr)
+@ stdcall BCryptRemoveContextFunctionProvider(long wstr long wstr wstr)
 @ stub BCryptResolveProviders
 @ stub BCryptSecretAgreement
 @ stub BCryptSetAuditingInterface
@@ -49,7 +49,7 @@
 @ stdcall BCryptSetProperty(ptr wstr ptr long long)
 @ stub BCryptSignHash
 @ stub BCryptUnregisterConfigChangeNotify
-@ stub BCryptUnregisterProvider
+@ stdcall BCryptUnregisterProvider(wstr)
 @ stub BCryptVerifySignature
 @ stub GetAsymmetricEncryptionInterface
 @ stub GetCipherInterface
diff --git a/dlls/bcrypt/bcrypt_main.c b/dlls/bcrypt/bcrypt_main.c
index 765f7589bee..3bdc463904e 100644
--- a/dlls/bcrypt/bcrypt_main.c
+++ b/dlls/bcrypt/bcrypt_main.c
@@ -122,6 +122,42 @@ static void gnutls_uninitialize(void)
 }
 #endif /* HAVE_GNUTLS_CIPHER_INIT && !HAVE_COMMONCRYPTO_COMMONCRYPTOR_H */
 
+NTSTATUS WINAPI BCryptAddContextFunction(ULONG table, LPCWSTR context, ULONG iface, LPCWSTR function, ULONG pos)
+{
+    FIXME("%08x, %s, %08x, %s, %u: stub\n", table, debugstr_w(context), iface, debugstr_w(function), pos);
+    return STATUS_SUCCESS;
+}
+
+NTSTATUS WINAPI BCryptAddContextFunctionProvider(ULONG table, LPCWSTR context, ULONG iface, LPCWSTR function, LPCWSTR provider, ULONG pos)
+{
+    FIXME("%08x, %s, %08x, %s, %s, %u: stub\n", table, debugstr_w(context), iface, debugstr_w(function), debugstr_w(provider), pos);
+    return STATUS_SUCCESS;
+}
+
+NTSTATUS WINAPI BCryptRemoveContextFunction(ULONG table, LPCWSTR context, ULONG iface, LPCWSTR function)
+{
+    FIXME("%08x, %s, %08x, %s: stub\n", table, debugstr_w(context), iface, debugstr_w(function));
+    return STATUS_NOT_IMPLEMENTED;
+}
+
+NTSTATUS WINAPI BCryptRemoveContextFunctionProvider(ULONG table, LPCWSTR context, ULONG iface, LPCWSTR function, LPCWSTR provider)
+{
+    FIXME("%08x, %s, %08x, %s, %s: stub\n", table, debugstr_w(context), iface, debugstr_w(function), debugstr_w(provider));
+    return STATUS_NOT_IMPLEMENTED;
+}
+
+NTSTATUS WINAPI BCryptRegisterProvider(LPCWSTR provider, ULONG flags, PCRYPT_PROVIDER_REG reg)
+{
+    FIXME("%s, %08x, %p: stub\n", debugstr_w(provider), flags, reg);
+    return STATUS_SUCCESS;
+}
+
+NTSTATUS WINAPI BCryptUnregisterProvider(LPCWSTR provider)
+{
+    FIXME("%s: stub\n", debugstr_w(provider));
+    return STATUS_NOT_IMPLEMENTED;
+}
+
 NTSTATUS WINAPI BCryptEnumAlgorithms(ULONG dwAlgOperations, ULONG *pAlgCount,
                                      BCRYPT_ALGORITHM_IDENTIFIER **ppAlgList, ULONG dwFlags)
 {
diff --git a/dlls/ncrypt/ncrypt.spec b/dlls/ncrypt/ncrypt.spec
index 1a78853bf49..5d371210d9e 100644
--- a/dlls/ncrypt/ncrypt.spec
+++ b/dlls/ncrypt/ncrypt.spec
@@ -1,5 +1,5 @@
-@ stub BCryptAddContextFunction
-@ stub BCryptAddContextFunctionProvider
+@ stdcall BCryptAddContextFunction(long wstr long wstr long) bcrypt.BCryptAddContextFunction
+@ stdcall BCryptAddContextFunctionProvider(long wstr long wstr wstr long) bcrypt.BCryptAddContextFunctionProvider
 @ stdcall BCryptCloseAlgorithmProvider(ptr long) bcrypt.BCryptCloseAlgorithmProvider
 @ stub BCryptConfigureContext
 @ stub BCryptConfigureContextFunction
@@ -42,9 +42,9 @@
 @ stub BCryptQueryContextFunctionProperty
 @ stub BCryptQueryProviderRegistration
 @ stub BCryptRegisterConfigChangeNotify
-@ stub BCryptRegisterProvider
-@ stub BCryptRemoveContextFunction
-@ stub BCryptRemoveContextFunctionProvider
+@ stdcall BCryptRegisterProvider(wstr long ptr) bcrypt.BCryptRegisterProvider
+@ stdcall BCryptRemoveContextFunction(long wstr long wstr) bcrypt.BCryptRemoveContextFunction
+@ stdcall BCryptRemoveContextFunctionProvider(long wstr long wstr wstr) bcrypt.BCryptRemoveContextFunctionProvider
 @ stub BCryptResolveProviders
 @ stub BCryptSecretAgreement
 @ stub BCryptSetAuditingInterface
@@ -52,7 +52,7 @@
 @ stdcall BCryptSetProperty(ptr wstr ptr long long) bcrypt.BCryptSetProperty
 @ stub BCryptSignHash
 @ stub BCryptUnregisterConfigChangeNotify
-@ stub BCryptUnregisterProvider
+@ stdcall BCryptUnregisterProvider(wstr) bcrypt.BCryptUnregisterProvider
 @ stub BCryptVerifySignature
 @ stub GetIsolationServerInterface
 @ stub GetKeyStorageInterface
diff --git a/include/bcrypt.h b/include/bcrypt.h
index 7c3c8d0744d..1f7093c25a3 100644
--- a/include/bcrypt.h
+++ b/include/bcrypt.h
@@ -94,6 +94,29 @@ typedef struct __BCRYPT_KEY_LENGTHS_STRUCT
     ULONG dwIncrement;
 } BCRYPT_KEY_LENGTHS_STRUCT;
 
+typedef struct _CRYPT_INTERFACE_REG
+{
+    ULONG dwInterface;
+    ULONG dwFlags;
+    ULONG cFunctions;
+    PWSTR *rgpszFunctions;
+} CRYPT_INTERFACE_REG, *PCRYPT_INTERFACE_REG;
+
+typedef struct _CRYPT_IMAGE_REG
+{
+    PWSTR pszImage;
+    ULONG cInterfaces;
+    PCRYPT_INTERFACE_REG *rgpInterfaces;
+} CRYPT_IMAGE_REG, *PCRYPT_IMAGE_REG;
+
+typedef struct _CRYPT_PROVIDER_REG
+{
+    ULONG cAliases;
+    PWSTR *rgpszAliases;
+    PCRYPT_IMAGE_REG pUM;
+    PCRYPT_IMAGE_REG pKM;
+} CRYPT_PROVIDER_REG, *PCRYPT_PROVIDER_REG;
+
 typedef PVOID BCRYPT_ALG_HANDLE;
 typedef PVOID BCRYPT_KEY_HANDLE;
 typedef PVOID BCRYPT_HANDLE;