freerdp/winpr/libwinpr/sspi/Negotiate/negotiate.c

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2023-05-09 21:29:50 +00:00
/**
* WinPR: Windows Portable Runtime
* Negotiate Security Package
*
* Copyright 2011-2014 Marc-Andre Moreau <marcandre.moreau@gmail.com>
* Copyright 2017 Dorian Ducournau <dorian.ducournau@gmail.com>
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <winpr/crt.h>
#include <winpr/sspi.h>
#include <winpr/tchar.h>
#include "negotiate.h"
#include "../sspi.h"
#include "../log.h"
#define TAG WINPR_TAG("negotiate")
extern const SecurityFunctionTableA NTLM_SecurityFunctionTableA;
extern const SecurityFunctionTableW NTLM_SecurityFunctionTableW;
extern const SecurityFunctionTableA KERBEROS_SecurityFunctionTableA;
extern const SecurityFunctionTableW KERBEROS_SecurityFunctionTableW;
#ifdef WITH_GSSAPI
static BOOL ErrorInitContextKerberos = FALSE;
#else
static BOOL ErrorInitContextKerberos = TRUE;
#endif
const SecPkgInfoA NEGOTIATE_SecPkgInfoA = {
0x00083BB3, /* fCapabilities */
1, /* wVersion */
0x0009, /* wRPCID */
0x00002FE0, /* cbMaxToken */
"Negotiate", /* Name */
"Microsoft Package Negotiator" /* Comment */
};
static WCHAR NEGOTIATE_SecPkgInfoW_Name[] = { 'N', 'e', 'g', 'o', 't', 'i', 'a', 't', 'e', '\0' };
static WCHAR NEGOTIATE_SecPkgInfoW_Comment[] = { 'M', 'i', 'c', 'r', 'o', 's', 'o', 'f', 't', ' ',
'P', 'a', 'c', 'k', 'a', 'g', 'e', ' ', 'N', 'e',
'g', 'o', 't', 'i', 'a', 't', 'o', 'r', '\0' };
const SecPkgInfoW NEGOTIATE_SecPkgInfoW = {
0x00083BB3, /* fCapabilities */
1, /* wVersion */
0x0009, /* wRPCID */
0x00002FE0, /* cbMaxToken */
NEGOTIATE_SecPkgInfoW_Name, /* Name */
NEGOTIATE_SecPkgInfoW_Comment /* Comment */
};
static void negotiate_SetSubPackage(NEGOTIATE_CONTEXT* context, const TCHAR* name)
{
if (_tcsnccmp(name, KERBEROS_SSP_NAME, ARRAYSIZE(KERBEROS_SSP_NAME)) == 0)
{
context->sspiA = (SecurityFunctionTableA*)&KERBEROS_SecurityFunctionTableA;
context->sspiW = (SecurityFunctionTableW*)&KERBEROS_SecurityFunctionTableW;
context->kerberos = TRUE;
}
else
{
context->sspiA = (SecurityFunctionTableA*)&NTLM_SecurityFunctionTableA;
context->sspiW = (SecurityFunctionTableW*)&NTLM_SecurityFunctionTableW;
context->kerberos = FALSE;
}
}
static NEGOTIATE_CONTEXT* negotiate_ContextNew(void)
{
NEGOTIATE_CONTEXT* context;
context = (NEGOTIATE_CONTEXT*)calloc(1, sizeof(NEGOTIATE_CONTEXT));
if (!context)
return NULL;
context->NegotiateFlags = 0;
context->state = NEGOTIATE_STATE_INITIAL;
SecInvalidateHandle(&(context->SubContext));
negotiate_SetSubPackage(context, KERBEROS_SSP_NAME);
return context;
}
static void negotiate_ContextFree(NEGOTIATE_CONTEXT* context)
{
free(context);
}
static SECURITY_STATUS SEC_ENTRY negotiate_InitializeSecurityContextW(
PCredHandle phCredential, PCtxtHandle phContext, SEC_WCHAR* pszTargetName, ULONG fContextReq,
ULONG Reserved1, ULONG TargetDataRep, PSecBufferDesc pInput, ULONG Reserved2,
PCtxtHandle phNewContext, PSecBufferDesc pOutput, PULONG pfContextAttr, PTimeStamp ptsExpiry)
{
SECURITY_STATUS status;
NEGOTIATE_CONTEXT* context;
context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);
if (!context)
{
context = negotiate_ContextNew();
if (!context)
return SEC_E_INTERNAL_ERROR;
sspi_SecureHandleSetLowerPointer(phNewContext, context);
sspi_SecureHandleSetUpperPointer(phNewContext, (void*)NEGO_SSP_NAME);
}
/* if Kerberos has previously failed or WITH_GSSAPI is not defined, we use NTLM directly */
if (ErrorInitContextKerberos == FALSE)
{
if (!pInput)
{
negotiate_SetSubPackage(context, KERBEROS_SSP_NAME);
}
status = context->sspiW->InitializeSecurityContextW(
phCredential, &(context->SubContext), pszTargetName, fContextReq, Reserved1,
TargetDataRep, pInput, Reserved2, &(context->SubContext), pOutput, pfContextAttr,
ptsExpiry);
if (status == SEC_E_NO_CREDENTIALS)
{
WLog_WARN(TAG, "No Kerberos credentials. Retry with NTLM");
ErrorInitContextKerberos = TRUE;
context->sspiA->DeleteSecurityContext(&(context->SubContext));
negotiate_ContextFree(context);
return status;
}
}
else
{
if (!pInput)
{
context->sspiA->DeleteSecurityContext(&(context->SubContext));
negotiate_SetSubPackage(context, NTLM_SSP_NAME);
}
status = context->sspiW->InitializeSecurityContextW(
phCredential, &(context->SubContext), pszTargetName, fContextReq, Reserved1,
TargetDataRep, pInput, Reserved2, &(context->SubContext), pOutput, pfContextAttr,
ptsExpiry);
}
return status;
}
static SECURITY_STATUS SEC_ENTRY negotiate_InitializeSecurityContextA(
PCredHandle phCredential, PCtxtHandle phContext, SEC_CHAR* pszTargetName, ULONG fContextReq,
ULONG Reserved1, ULONG TargetDataRep, PSecBufferDesc pInput, ULONG Reserved2,
PCtxtHandle phNewContext, PSecBufferDesc pOutput, PULONG pfContextAttr, PTimeStamp ptsExpiry)
{
SECURITY_STATUS status;
NEGOTIATE_CONTEXT* context;
context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);
if (!context)
{
context = negotiate_ContextNew();
if (!context)
return SEC_E_INTERNAL_ERROR;
sspi_SecureHandleSetLowerPointer(phNewContext, context);
sspi_SecureHandleSetUpperPointer(phNewContext, (void*)NEGO_SSP_NAME);
}
/* if Kerberos has previously failed or WITH_GSSAPI is not defined, we use NTLM directly */
if (ErrorInitContextKerberos == FALSE)
{
if (!pInput)
{
negotiate_SetSubPackage(context, KERBEROS_SSP_NAME);
}
status = context->sspiA->InitializeSecurityContextA(
phCredential, &(context->SubContext), pszTargetName, fContextReq, Reserved1,
TargetDataRep, pInput, Reserved2, &(context->SubContext), pOutput, pfContextAttr,
ptsExpiry);
if (status == SEC_E_NO_CREDENTIALS)
{
WLog_WARN(TAG, "No Kerberos credentials. Retry with NTLM");
ErrorInitContextKerberos = TRUE;
context->sspiA->DeleteSecurityContext(&(context->SubContext));
negotiate_ContextFree(context);
return status;
}
}
else
{
if (!pInput)
{
context->sspiA->DeleteSecurityContext(&(context->SubContext));
negotiate_SetSubPackage(context, NTLM_SSP_NAME);
}
status = context->sspiA->InitializeSecurityContextA(
phCredential, &(context->SubContext), pszTargetName, fContextReq, Reserved1,
TargetDataRep, pInput, Reserved2, &(context->SubContext), pOutput, pfContextAttr,
ptsExpiry);
}
return status;
}
static SECURITY_STATUS SEC_ENTRY negotiate_AcceptSecurityContext(
PCredHandle phCredential, PCtxtHandle phContext, PSecBufferDesc pInput, ULONG fContextReq,
ULONG TargetDataRep, PCtxtHandle phNewContext, PSecBufferDesc pOutput, PULONG pfContextAttr,
PTimeStamp ptsTimeStamp)
{
SECURITY_STATUS status;
NEGOTIATE_CONTEXT* context;
context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);
if (!context)
{
context = negotiate_ContextNew();
if (!context)
return SEC_E_INTERNAL_ERROR;
sspi_SecureHandleSetLowerPointer(phNewContext, context);
sspi_SecureHandleSetUpperPointer(phNewContext, (void*)NEGO_SSP_NAME);
}
negotiate_SetSubPackage(context, NTLM_SSP_NAME); /* server-side Kerberos not yet implemented */
status = context->sspiA->AcceptSecurityContext(
phCredential, &(context->SubContext), pInput, fContextReq, TargetDataRep,
&(context->SubContext), pOutput, pfContextAttr, ptsTimeStamp);
if (status != SEC_E_OK)
{
WLog_WARN(TAG, "AcceptSecurityContext status %s [0x%08" PRIX32 "]",
GetSecurityStatusString(status), status);
}
return status;
}
static SECURITY_STATUS SEC_ENTRY negotiate_CompleteAuthToken(PCtxtHandle phContext,
PSecBufferDesc pToken)
{
NEGOTIATE_CONTEXT* context;
SECURITY_STATUS status = SEC_E_OK;
context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);
if (!context)
return SEC_E_INVALID_HANDLE;
if (context->sspiW->CompleteAuthToken)
status = context->sspiW->CompleteAuthToken(&(context->SubContext), pToken);
return status;
}
static SECURITY_STATUS SEC_ENTRY negotiate_DeleteSecurityContext(PCtxtHandle phContext)
{
NEGOTIATE_CONTEXT* context;
SECURITY_STATUS status = SEC_E_OK;
context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);
if (!context)
return SEC_E_INVALID_HANDLE;
if (context->sspiW->DeleteSecurityContext)
status = context->sspiW->DeleteSecurityContext(&(context->SubContext));
negotiate_ContextFree(context);
return status;
}
static SECURITY_STATUS SEC_ENTRY negotiate_ImpersonateSecurityContext(PCtxtHandle phContext)
{
NEGOTIATE_CONTEXT* context;
SECURITY_STATUS status = SEC_E_OK;
context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);
if (!phContext)
return SEC_E_INVALID_HANDLE;
if (context->sspiW->ImpersonateSecurityContext)
status = context->sspiW->ImpersonateSecurityContext(&(context->SubContext));
return status;
}
static SECURITY_STATUS SEC_ENTRY negotiate_RevertSecurityContext(PCtxtHandle phContext)
{
NEGOTIATE_CONTEXT* context;
SECURITY_STATUS status = SEC_E_OK;
context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);
if (!phContext)
return SEC_E_INVALID_HANDLE;
if (context->sspiW->RevertSecurityContext)
status = context->sspiW->RevertSecurityContext(&(context->SubContext));
return status;
}
static SECURITY_STATUS SEC_ENTRY negotiate_QueryContextAttributesW(PCtxtHandle phContext,
ULONG ulAttribute, void* pBuffer)
{
NEGOTIATE_CONTEXT* context;
SECURITY_STATUS status = SEC_E_OK;
context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);
if (!phContext)
return SEC_E_INVALID_HANDLE;
if (!pBuffer)
return SEC_E_INSUFFICIENT_MEMORY;
if (context->sspiW->QueryContextAttributesW)
status =
context->sspiW->QueryContextAttributesW(&(context->SubContext), ulAttribute, pBuffer);
return status;
}
static SECURITY_STATUS SEC_ENTRY negotiate_QueryContextAttributesA(PCtxtHandle phContext,
ULONG ulAttribute, void* pBuffer)
{
NEGOTIATE_CONTEXT* context;
SECURITY_STATUS status = SEC_E_OK;
context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);
if (!phContext)
return SEC_E_INVALID_HANDLE;
if (!pBuffer)
return SEC_E_INSUFFICIENT_MEMORY;
if (context->sspiA->QueryContextAttributesA)
status =
context->sspiA->QueryContextAttributesA(&(context->SubContext), ulAttribute, pBuffer);
return status;
}
static SECURITY_STATUS SEC_ENTRY negotiate_SetContextAttributesW(PCtxtHandle phContext,
ULONG ulAttribute, void* pBuffer,
ULONG cbBuffer)
{
NEGOTIATE_CONTEXT* context;
SECURITY_STATUS status = SEC_E_OK;
context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);
if (!phContext)
return SEC_E_INVALID_HANDLE;
if (!pBuffer)
return SEC_E_INSUFFICIENT_MEMORY;
if (context->sspiW->SetContextAttributesW)
status = context->sspiW->SetContextAttributesW(&(context->SubContext), ulAttribute, pBuffer,
cbBuffer);
return status;
}
static SECURITY_STATUS SEC_ENTRY negotiate_SetContextAttributesA(PCtxtHandle phContext,
ULONG ulAttribute, void* pBuffer,
ULONG cbBuffer)
{
NEGOTIATE_CONTEXT* context;
SECURITY_STATUS status = SEC_E_OK;
context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);
if (!phContext)
return SEC_E_INVALID_HANDLE;
if (!pBuffer)
return SEC_E_INSUFFICIENT_MEMORY;
if (context->sspiA->SetContextAttributesA)
status = context->sspiA->SetContextAttributesA(&(context->SubContext), ulAttribute, pBuffer,
cbBuffer);
return status;
}
static SECURITY_STATUS SEC_ENTRY negotiate_AcquireCredentialsHandleW(
SEC_WCHAR* pszPrincipal, SEC_WCHAR* pszPackage, ULONG fCredentialUse, void* pvLogonID,
void* pAuthData, SEC_GET_KEY_FN pGetKeyFn, void* pvGetKeyArgument, PCredHandle phCredential,
PTimeStamp ptsExpiry)
{
SSPI_CREDENTIALS* credentials;
SEC_WINNT_AUTH_IDENTITY* identity;
if ((fCredentialUse != SECPKG_CRED_OUTBOUND) && (fCredentialUse != SECPKG_CRED_INBOUND) &&
(fCredentialUse != SECPKG_CRED_BOTH))
{
return SEC_E_INVALID_PARAMETER;
}
credentials = sspi_CredentialsNew();
if (!credentials)
return SEC_E_INTERNAL_ERROR;
credentials->fCredentialUse = fCredentialUse;
credentials->pGetKeyFn = pGetKeyFn;
credentials->pvGetKeyArgument = pvGetKeyArgument;
identity = (SEC_WINNT_AUTH_IDENTITY*)pAuthData;
if (identity)
sspi_CopyAuthIdentity(&(credentials->identity), identity);
sspi_SecureHandleSetLowerPointer(phCredential, (void*)credentials);
sspi_SecureHandleSetUpperPointer(phCredential, (void*)NEGO_SSP_NAME);
return SEC_E_OK;
}
static SECURITY_STATUS SEC_ENTRY negotiate_AcquireCredentialsHandleA(
SEC_CHAR* pszPrincipal, SEC_CHAR* pszPackage, ULONG fCredentialUse, void* pvLogonID,
void* pAuthData, SEC_GET_KEY_FN pGetKeyFn, void* pvGetKeyArgument, PCredHandle phCredential,
PTimeStamp ptsExpiry)
{
SSPI_CREDENTIALS* credentials;
SEC_WINNT_AUTH_IDENTITY* identity;
if ((fCredentialUse != SECPKG_CRED_OUTBOUND) && (fCredentialUse != SECPKG_CRED_INBOUND) &&
(fCredentialUse != SECPKG_CRED_BOTH))
{
return SEC_E_INVALID_PARAMETER;
}
credentials = sspi_CredentialsNew();
if (!credentials)
return SEC_E_INTERNAL_ERROR;
credentials->fCredentialUse = fCredentialUse;
credentials->pGetKeyFn = pGetKeyFn;
credentials->pvGetKeyArgument = pvGetKeyArgument;
identity = (SEC_WINNT_AUTH_IDENTITY*)pAuthData;
if (identity)
sspi_CopyAuthIdentity(&(credentials->identity), identity);
sspi_SecureHandleSetLowerPointer(phCredential, (void*)credentials);
sspi_SecureHandleSetUpperPointer(phCredential, (void*)NEGO_SSP_NAME);
return SEC_E_OK;
}
static SECURITY_STATUS SEC_ENTRY negotiate_QueryCredentialsAttributesW(PCredHandle phCredential,
ULONG ulAttribute,
void* pBuffer)
{
WLog_ERR(TAG, "[%s]: TODO: Implement", __FUNCTION__);
return SEC_E_UNSUPPORTED_FUNCTION;
}
static SECURITY_STATUS SEC_ENTRY negotiate_QueryCredentialsAttributesA(PCredHandle phCredential,
ULONG ulAttribute,
void* pBuffer)
{
WLog_ERR(TAG, "[%s]: TODO: Implement", __FUNCTION__);
return SEC_E_UNSUPPORTED_FUNCTION;
}
static SECURITY_STATUS SEC_ENTRY negotiate_FreeCredentialsHandle(PCredHandle phCredential)
{
SSPI_CREDENTIALS* credentials;
if (!phCredential)
return SEC_E_INVALID_HANDLE;
credentials = (SSPI_CREDENTIALS*)sspi_SecureHandleGetLowerPointer(phCredential);
if (!credentials)
return SEC_E_INVALID_HANDLE;
sspi_CredentialsFree(credentials);
sspi_SecureHandleInvalidate(phCredential);
return SEC_E_OK;
}
static SECURITY_STATUS SEC_ENTRY negotiate_EncryptMessage(PCtxtHandle phContext, ULONG fQOP,
PSecBufferDesc pMessage,
ULONG MessageSeqNo)
{
NEGOTIATE_CONTEXT* context;
SECURITY_STATUS status = SEC_E_UNSUPPORTED_FUNCTION;
context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);
if (context->sspiW->EncryptMessage)
status =
context->sspiW->EncryptMessage(&(context->SubContext), fQOP, pMessage, MessageSeqNo);
else
WLog_WARN(TAG, "[%s] SSPI implementation of function is missing", __FUNCTION__);
return status;
}
static SECURITY_STATUS SEC_ENTRY negotiate_DecryptMessage(PCtxtHandle phContext,
PSecBufferDesc pMessage,
ULONG MessageSeqNo, ULONG* pfQOP)
{
NEGOTIATE_CONTEXT* context;
SECURITY_STATUS status = SEC_E_UNSUPPORTED_FUNCTION;
context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);
if (context->sspiW->DecryptMessage)
status =
context->sspiW->DecryptMessage(&(context->SubContext), pMessage, MessageSeqNo, pfQOP);
else
WLog_WARN(TAG, "[%s] SSPI implementation of function is missing", __FUNCTION__);
return status;
}
static SECURITY_STATUS SEC_ENTRY negotiate_MakeSignature(PCtxtHandle phContext, ULONG fQOP,
PSecBufferDesc pMessage,
ULONG MessageSeqNo)
{
NEGOTIATE_CONTEXT* context;
SECURITY_STATUS status = SEC_E_UNSUPPORTED_FUNCTION;
context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);
if (context->sspiW->MakeSignature)
status =
context->sspiW->MakeSignature(&(context->SubContext), fQOP, pMessage, MessageSeqNo);
else
WLog_WARN(TAG, "[%s] SSPI implementation of function is missing", __FUNCTION__);
return status;
}
static SECURITY_STATUS SEC_ENTRY negotiate_VerifySignature(PCtxtHandle phContext,
PSecBufferDesc pMessage,
ULONG MessageSeqNo, ULONG* pfQOP)
{
NEGOTIATE_CONTEXT* context;
SECURITY_STATUS status = SEC_E_UNSUPPORTED_FUNCTION;
context = (NEGOTIATE_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);
if (context->sspiW->VerifySignature)
status =
context->sspiW->VerifySignature(&(context->SubContext), pMessage, MessageSeqNo, pfQOP);
else
WLog_WARN(TAG, "[%s] SSPI implementation of function is missing", __FUNCTION__);
return status;
}
const SecurityFunctionTableA NEGOTIATE_SecurityFunctionTableA = {
1, /* dwVersion */
NULL, /* EnumerateSecurityPackages */
negotiate_QueryCredentialsAttributesA, /* QueryCredentialsAttributes */
negotiate_AcquireCredentialsHandleA, /* AcquireCredentialsHandle */
negotiate_FreeCredentialsHandle, /* FreeCredentialsHandle */
NULL, /* Reserved2 */
negotiate_InitializeSecurityContextA, /* InitializeSecurityContext */
negotiate_AcceptSecurityContext, /* AcceptSecurityContext */
negotiate_CompleteAuthToken, /* CompleteAuthToken */
negotiate_DeleteSecurityContext, /* DeleteSecurityContext */
NULL, /* ApplyControlToken */
negotiate_QueryContextAttributesA, /* QueryContextAttributes */
negotiate_ImpersonateSecurityContext, /* ImpersonateSecurityContext */
negotiate_RevertSecurityContext, /* RevertSecurityContext */
negotiate_MakeSignature, /* MakeSignature */
negotiate_VerifySignature, /* VerifySignature */
NULL, /* FreeContextBuffer */
NULL, /* QuerySecurityPackageInfo */
NULL, /* Reserved3 */
NULL, /* Reserved4 */
NULL, /* ExportSecurityContext */
NULL, /* ImportSecurityContext */
NULL, /* AddCredentials */
NULL, /* Reserved8 */
NULL, /* QuerySecurityContextToken */
negotiate_EncryptMessage, /* EncryptMessage */
negotiate_DecryptMessage, /* DecryptMessage */
negotiate_SetContextAttributesA, /* SetContextAttributes */
};
const SecurityFunctionTableW NEGOTIATE_SecurityFunctionTableW = {
1, /* dwVersion */
NULL, /* EnumerateSecurityPackages */
negotiate_QueryCredentialsAttributesW, /* QueryCredentialsAttributes */
negotiate_AcquireCredentialsHandleW, /* AcquireCredentialsHandle */
negotiate_FreeCredentialsHandle, /* FreeCredentialsHandle */
NULL, /* Reserved2 */
negotiate_InitializeSecurityContextW, /* InitializeSecurityContext */
negotiate_AcceptSecurityContext, /* AcceptSecurityContext */
negotiate_CompleteAuthToken, /* CompleteAuthToken */
negotiate_DeleteSecurityContext, /* DeleteSecurityContext */
NULL, /* ApplyControlToken */
negotiate_QueryContextAttributesW, /* QueryContextAttributes */
negotiate_ImpersonateSecurityContext, /* ImpersonateSecurityContext */
negotiate_RevertSecurityContext, /* RevertSecurityContext */
negotiate_MakeSignature, /* MakeSignature */
negotiate_VerifySignature, /* VerifySignature */
NULL, /* FreeContextBuffer */
NULL, /* QuerySecurityPackageInfo */
NULL, /* Reserved3 */
NULL, /* Reserved4 */
NULL, /* ExportSecurityContext */
NULL, /* ImportSecurityContext */
NULL, /* AddCredentials */
NULL, /* Reserved8 */
NULL, /* QuerySecurityContextToken */
negotiate_EncryptMessage, /* EncryptMessage */
negotiate_DecryptMessage, /* DecryptMessage */
negotiate_SetContextAttributesW, /* SetContextAttributes */
};