FreeRDP/libfreerdp-sspi/sspi.c
2012-03-05 17:23:22 -05:00

741 lines
18 KiB
C

/**
* FreeRDP: A Remote Desktop Protocol Implementation
* Security Support Provider Interface (SSPI)
*
* Copyright 2012 Marc-Andre Moreau <marcandre.moreau@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.
*/
#include <freerdp/utils/memory.h>
#include <freerdp/sspi/sspi.h>
#include "sspi.h"
/* Authentication Functions: http://msdn.microsoft.com/en-us/library/windows/desktop/aa374731/ */
extern const SEC_PKG_INFO NTLM_SEC_PKG_INFO;
extern const SEC_PKG_INFO CREDSSP_SEC_PKG_INFO;
const SECURITY_FUNCTION_TABLE SSPI_SECURITY_FUNCTION_TABLE;
extern const SECURITY_FUNCTION_TABLE NTLM_SECURITY_FUNCTION_TABLE;
extern const SECURITY_FUNCTION_TABLE CREDSSP_SECURITY_FUNCTION_TABLE;
const SEC_PKG_INFO* SEC_PKG_INFO_LIST[] =
{
&NTLM_SEC_PKG_INFO,
&CREDSSP_SEC_PKG_INFO
};
struct _SECURITY_FUNCTION_TABLE_NAME
{
char* Name;
const SECURITY_FUNCTION_TABLE* security_function_table;
};
typedef struct _SECURITY_FUNCTION_TABLE_NAME SECURITY_FUNCTION_TABLE_NAME;
const SECURITY_FUNCTION_TABLE_NAME SECURITY_FUNCTION_TABLE_NAME_LIST[] =
{
{ "NTLM", &NTLM_SECURITY_FUNCTION_TABLE },
{ "CREDSSP", &CREDSSP_SECURITY_FUNCTION_TABLE }
};
#define SEC_HANDLE_LOWER_MAX 0xFFFFFFFF
#define SEC_HANDLE_UPPER_MAX 0xFFFFFFFE
struct _CONTEXT_BUFFER_ALLOC_ENTRY
{
void* contextBuffer;
uint32 allocatorIndex;
};
typedef struct _CONTEXT_BUFFER_ALLOC_ENTRY CONTEXT_BUFFER_ALLOC_ENTRY;
struct _CONTEXT_BUFFER_ALLOC_TABLE
{
uint32 cEntries;
uint32 cMaxEntries;
CONTEXT_BUFFER_ALLOC_ENTRY* entries;
};
typedef struct _CONTEXT_BUFFER_ALLOC_TABLE CONTEXT_BUFFER_ALLOC_TABLE;
CONTEXT_BUFFER_ALLOC_TABLE ContextBufferAllocTable;
void sspi_ContextBufferAllocTableNew()
{
size_t size;
ContextBufferAllocTable.cEntries = 0;
ContextBufferAllocTable.cMaxEntries = 4;
size = sizeof(CONTEXT_BUFFER_ALLOC_ENTRY) * ContextBufferAllocTable.cMaxEntries;
ContextBufferAllocTable.entries = xzalloc(size);
}
void sspi_ContextBufferAllocTableGrow()
{
size_t size;
ContextBufferAllocTable.cEntries = 0;
ContextBufferAllocTable.cMaxEntries *= 2;
size = sizeof(CONTEXT_BUFFER_ALLOC_ENTRY) * ContextBufferAllocTable.cMaxEntries;
ContextBufferAllocTable.entries = xrealloc(ContextBufferAllocTable.entries, size);
memset((void*) &ContextBufferAllocTable.entries[ContextBufferAllocTable.cMaxEntries / 2], 0, size / 2);
}
void sspi_ContextBufferAllocTableFree()
{
ContextBufferAllocTable.cEntries = ContextBufferAllocTable.cMaxEntries = 0;
xfree(ContextBufferAllocTable.entries);
}
void* sspi_ContextBufferAlloc(uint32 allocatorIndex, size_t size)
{
int index;
void* contextBuffer;
for (index = 0; index < (int) ContextBufferAllocTable.cMaxEntries; index++)
{
if (ContextBufferAllocTable.entries[index].contextBuffer == NULL)
{
contextBuffer = xzalloc(size);
ContextBufferAllocTable.cEntries++;
ContextBufferAllocTable.entries[index].contextBuffer = contextBuffer;
ContextBufferAllocTable.entries[index].allocatorIndex = allocatorIndex;
return ContextBufferAllocTable.entries[index].contextBuffer;
}
}
/* no available entry was found, the table needs to be grown */
sspi_ContextBufferAllocTableGrow();
/* the next call to sspi_ContextBufferAlloc() should now succeed */
return sspi_ContextBufferAlloc(allocatorIndex, size);
}
void FreeContextBuffer_EnumerateSecurityPackages(void* contextBuffer);
void FreeContextBuffer_QuerySecurityPackageInfo(void* contextBuffer);
void sspi_ContextBufferFree(void* contextBuffer)
{
int index;
uint32 allocatorIndex;
for (index = 0; index < (int) ContextBufferAllocTable.cMaxEntries; index++)
{
if (contextBuffer == ContextBufferAllocTable.entries[index].contextBuffer)
{
contextBuffer = ContextBufferAllocTable.entries[index].contextBuffer;
allocatorIndex = ContextBufferAllocTable.entries[index].allocatorIndex;
ContextBufferAllocTable.cEntries--;
ContextBufferAllocTable.entries[index].allocatorIndex = 0;
ContextBufferAllocTable.entries[index].contextBuffer = NULL;
switch (allocatorIndex)
{
case EnumerateSecurityPackagesIndex:
FreeContextBuffer_EnumerateSecurityPackages(contextBuffer);
break;
case QuerySecurityPackageInfoIndex:
FreeContextBuffer_QuerySecurityPackageInfo(contextBuffer);
break;
}
}
}
}
CREDENTIALS* sspi_CredentialsNew()
{
CREDENTIALS* credentials;
credentials = xnew(CREDENTIALS);
if (credentials != NULL)
{
}
return credentials;
}
void sspi_CredentialsFree(CREDENTIALS* credentials)
{
if (!credentials)
return;
xfree(credentials);
}
void sspi_SecBufferAlloc(SEC_BUFFER* sec_buffer, size_t size)
{
sec_buffer->cbBuffer = size;
sec_buffer->pvBuffer = xzalloc(size);
}
void sspi_SecBufferFree(SEC_BUFFER* sec_buffer)
{
sec_buffer->cbBuffer = 0;
xfree(sec_buffer->pvBuffer);
sec_buffer->pvBuffer = NULL;
}
SEC_HANDLE* sspi_SecureHandleAlloc()
{
SEC_HANDLE* handle = xmalloc(sizeof(SEC_HANDLE));
sspi_SecureHandleInit(handle);
return handle;
}
void sspi_SecureHandleInit(SEC_HANDLE* handle)
{
if (!handle)
return;
memset(handle, 0xFF, sizeof(SEC_HANDLE));
}
void sspi_SecureHandleInvalidate(SEC_HANDLE* handle)
{
if (!handle)
return;
sspi_SecureHandleInit(handle);
}
void* sspi_SecureHandleGetLowerPointer(SEC_HANDLE* handle)
{
void* pointer;
if (!handle)
return NULL;
pointer = (void*) ~((size_t) handle->dwLower);
return pointer;
}
void sspi_SecureHandleSetLowerPointer(SEC_HANDLE* handle, void* pointer)
{
if (!handle)
return;
handle->dwLower = (uint32*) (~((size_t) pointer));
}
void* sspi_SecureHandleGetUpperPointer(SEC_HANDLE* handle)
{
void* pointer;
if (!handle)
return NULL;
pointer = (void*) ~((size_t) handle->dwUpper);
return pointer;
}
void sspi_SecureHandleSetUpperPointer(SEC_HANDLE* handle, void* pointer)
{
if (!handle)
return;
handle->dwUpper = (uint32*) (~((size_t) pointer));
}
void sspi_SecureHandleFree(SEC_HANDLE* handle)
{
if (!handle)
return;
xfree(handle);
}
SECURITY_FUNCTION_TABLE* sspi_GetSecurityFunctionTableByName(const char* Name)
{
int index;
uint32 cPackages;
cPackages = ARRAY_SIZE(SEC_PKG_INFO_LIST);
for (index = 0; index < (int) cPackages; index++)
{
if (strcmp(Name, SECURITY_FUNCTION_TABLE_NAME_LIST[index].Name) == 0)
{
return (SECURITY_FUNCTION_TABLE*) SECURITY_FUNCTION_TABLE_NAME_LIST[index].security_function_table;
}
}
return NULL;
}
void sspi_GlobalInit()
{
sspi_ContextBufferAllocTableNew();
}
void sspi_GlobalFinish()
{
sspi_ContextBufferAllocTableFree();
}
/* Package Management */
SECURITY_STATUS EnumerateSecurityPackages(uint32* pcPackages, SEC_PKG_INFO** ppPackageInfo)
{
int index;
size_t size;
uint32 cPackages;
SEC_PKG_INFO* pPackageInfo;
cPackages = ARRAY_SIZE(SEC_PKG_INFO_LIST);
size = sizeof(SEC_PKG_INFO) * cPackages;
pPackageInfo = (SEC_PKG_INFO*) sspi_ContextBufferAlloc(EnumerateSecurityPackagesIndex, size);
for (index = 0; index < (int) cPackages; index++)
{
pPackageInfo[index].fCapabilities = SEC_PKG_INFO_LIST[index]->fCapabilities;
pPackageInfo[index].wVersion = SEC_PKG_INFO_LIST[index]->wVersion;
pPackageInfo[index].wRPCID = SEC_PKG_INFO_LIST[index]->wRPCID;
pPackageInfo[index].cbMaxToken = SEC_PKG_INFO_LIST[index]->cbMaxToken;
pPackageInfo[index].Name = xstrdup(SEC_PKG_INFO_LIST[index]->Name);
pPackageInfo[index].Comment = xstrdup(SEC_PKG_INFO_LIST[index]->Comment);
}
*(pcPackages) = cPackages;
*(ppPackageInfo) = pPackageInfo;
return SEC_E_OK;
}
void FreeContextBuffer_EnumerateSecurityPackages(void* contextBuffer)
{
int index;
uint32 cPackages;
SEC_PKG_INFO* pPackageInfo = (SEC_PKG_INFO*) contextBuffer;
cPackages = ARRAY_SIZE(SEC_PKG_INFO_LIST);
for (index = 0; index < (int) cPackages; index++)
{
if (pPackageInfo[index].Name)
xfree(pPackageInfo[index].Name);
if (pPackageInfo[index].Comment)
xfree(pPackageInfo[index].Comment);
}
xfree(pPackageInfo);
}
SECURITY_FUNCTION_TABLE* InitSecurityInterface(void)
{
SECURITY_FUNCTION_TABLE* security_function_table;
security_function_table = xnew(SECURITY_FUNCTION_TABLE);
memcpy((void*) security_function_table, (void*) &SSPI_SECURITY_FUNCTION_TABLE, sizeof(SECURITY_FUNCTION_TABLE));
return security_function_table;
}
SECURITY_STATUS QuerySecurityPackageInfo(char* pszPackageName, SEC_PKG_INFO** ppPackageInfo)
{
int index;
size_t size;
uint32 cPackages;
SEC_PKG_INFO* pPackageInfo;
cPackages = ARRAY_SIZE(SEC_PKG_INFO_LIST);
for (index = 0; index < (int) cPackages; index++)
{
if (strcmp(pszPackageName, SEC_PKG_INFO_LIST[index]->Name) == 0)
{
size = sizeof(SEC_PKG_INFO);
pPackageInfo = (SEC_PKG_INFO*) sspi_ContextBufferAlloc(QuerySecurityPackageInfoIndex, size);
pPackageInfo->fCapabilities = SEC_PKG_INFO_LIST[index]->fCapabilities;
pPackageInfo->wVersion = SEC_PKG_INFO_LIST[index]->wVersion;
pPackageInfo->wRPCID = SEC_PKG_INFO_LIST[index]->wRPCID;
pPackageInfo->cbMaxToken = SEC_PKG_INFO_LIST[index]->cbMaxToken;
pPackageInfo->Name = xstrdup(SEC_PKG_INFO_LIST[index]->Name);
pPackageInfo->Comment = xstrdup(SEC_PKG_INFO_LIST[index]->Comment);
*(ppPackageInfo) = pPackageInfo;
return SEC_E_OK;
}
}
*(ppPackageInfo) = NULL;
return SEC_E_SECPKG_NOT_FOUND;
}
void FreeContextBuffer_QuerySecurityPackageInfo(void* contextBuffer)
{
SEC_PKG_INFO* pPackageInfo = (SEC_PKG_INFO*) contextBuffer;
if (pPackageInfo->Name)
xfree(pPackageInfo->Name);
if (pPackageInfo->Comment)
xfree(pPackageInfo->Comment);
xfree(pPackageInfo);
}
/* Credential Management */
SECURITY_STATUS AcquireCredentialsHandle(char* pszPrincipal, char* pszPackage,
uint32 fCredentialUse, void* pvLogonID, void* pAuthData, void* pGetKeyFn,
void* pvGetKeyArgument, CRED_HANDLE* phCredential, SEC_TIMESTAMP* ptsExpiry)
{
SECURITY_STATUS status;
SECURITY_FUNCTION_TABLE* table = sspi_GetSecurityFunctionTableByName(pszPackage);
if (!table)
return SEC_E_SECPKG_NOT_FOUND;
if (table->AcquireCredentialsHandle == NULL)
return SEC_E_UNSUPPORTED_FUNCTION;
status = table->AcquireCredentialsHandle(pszPrincipal, pszPackage, fCredentialUse,
pvLogonID, pAuthData, pGetKeyFn, pvGetKeyArgument, phCredential, ptsExpiry);
return status;
}
SECURITY_STATUS ExportSecurityContext(CTXT_HANDLE* phContext, uint32 fFlags, SEC_BUFFER* pPackedContext, void* pToken)
{
return SEC_E_OK;
}
SECURITY_STATUS FreeCredentialsHandle(CRED_HANDLE* phCredential)
{
char* Name;
SECURITY_STATUS status;
SECURITY_FUNCTION_TABLE* table;
Name = (char*) sspi_SecureHandleGetUpperPointer(phCredential);
if (!Name)
return SEC_E_SECPKG_NOT_FOUND;
table = sspi_GetSecurityFunctionTableByName(Name);
if (!table)
return SEC_E_SECPKG_NOT_FOUND;
if (table->FreeCredentialsHandle == NULL)
return SEC_E_UNSUPPORTED_FUNCTION;
status = table->FreeCredentialsHandle(phCredential);
return status;
}
SECURITY_STATUS ImportSecurityContext(char* pszPackage, SEC_BUFFER* pPackedContext, void* pToken, CTXT_HANDLE* phContext)
{
return SEC_E_OK;
}
SECURITY_STATUS QueryCredentialsAttributes(CRED_HANDLE* phCredential, uint32 ulAttribute, void* pBuffer)
{
char* Name;
SECURITY_STATUS status;
SECURITY_FUNCTION_TABLE* table;
Name = (char*) sspi_SecureHandleGetUpperPointer(phCredential);
if (!Name)
return SEC_E_SECPKG_NOT_FOUND;
table = sspi_GetSecurityFunctionTableByName(Name);
if (!table)
return SEC_E_SECPKG_NOT_FOUND;
if (table->QueryCredentialsAttributes == NULL)
return SEC_E_UNSUPPORTED_FUNCTION;
status = table->QueryCredentialsAttributes(phCredential, ulAttribute, pBuffer);
return status;
}
/* Context Management */
SECURITY_STATUS AcceptSecurityContext(CRED_HANDLE* phCredential, CTXT_HANDLE* phContext,
SEC_BUFFER_DESC* pInput, uint32 fContextReq, uint32 TargetDataRep, CTXT_HANDLE* phNewContext,
SEC_BUFFER_DESC* pOutput, uint32* pfContextAttr, SEC_TIMESTAMP* ptsTimeStamp)
{
char* Name;
SECURITY_STATUS status;
SECURITY_FUNCTION_TABLE* table;
Name = (char*) sspi_SecureHandleGetUpperPointer(phCredential);
if (!Name)
return SEC_E_SECPKG_NOT_FOUND;
table = sspi_GetSecurityFunctionTableByName(Name);
if (!table)
return SEC_E_SECPKG_NOT_FOUND;
if (table->AcceptSecurityContext == NULL)
return SEC_E_UNSUPPORTED_FUNCTION;
status = table->AcceptSecurityContext(phCredential, phContext, pInput, fContextReq,
TargetDataRep, phNewContext, pOutput, pfContextAttr, ptsTimeStamp);
return status;
}
SECURITY_STATUS ApplyControlToken(CTXT_HANDLE* phContext, SEC_BUFFER_DESC* pInput)
{
return SEC_E_OK;
}
SECURITY_STATUS CompleteAuthToken(CTXT_HANDLE* phContext, SEC_BUFFER_DESC* pToken)
{
return SEC_E_OK;
}
SECURITY_STATUS DeleteSecurityContext(CTXT_HANDLE* phContext)
{
return SEC_E_OK;
}
SECURITY_STATUS FreeContextBuffer(void* pvContextBuffer)
{
if (!pvContextBuffer)
return SEC_E_INVALID_HANDLE;
sspi_ContextBufferFree(pvContextBuffer);
return SEC_E_OK;
}
SECURITY_STATUS ImpersonateSecurityContext(CTXT_HANDLE* phContext)
{
return SEC_E_OK;
}
SECURITY_STATUS InitializeSecurityContext(CRED_HANDLE* phCredential, CTXT_HANDLE* phContext,
char* pszTargetName, uint32 fContextReq, uint32 Reserved1, uint32 TargetDataRep,
SEC_BUFFER_DESC* pInput, uint32 Reserved2, CTXT_HANDLE* phNewContext,
SEC_BUFFER_DESC* pOutput, uint32* pfContextAttr, SEC_TIMESTAMP* ptsExpiry)
{
char* Name;
SECURITY_STATUS status;
SECURITY_FUNCTION_TABLE* table;
Name = (char*) sspi_SecureHandleGetUpperPointer(phCredential);
if (!Name)
return SEC_E_SECPKG_NOT_FOUND;
table = sspi_GetSecurityFunctionTableByName(Name);
if (!table)
return SEC_E_SECPKG_NOT_FOUND;
if (table->InitializeSecurityContext == NULL)
return SEC_E_UNSUPPORTED_FUNCTION;
status = table->InitializeSecurityContext(phCredential, phContext,
pszTargetName, fContextReq, Reserved1, TargetDataRep,
pInput, Reserved2, phNewContext, pOutput, pfContextAttr, ptsExpiry);
return status;
}
SECURITY_STATUS QueryContextAttributes(CTXT_HANDLE* phContext, uint32 ulAttribute, void* pBuffer)
{
char* Name;
SECURITY_STATUS status;
SECURITY_FUNCTION_TABLE* table;
Name = (char*) sspi_SecureHandleGetUpperPointer(phContext);
if (!Name)
return SEC_E_SECPKG_NOT_FOUND;
table = sspi_GetSecurityFunctionTableByName(Name);
if (!table)
return SEC_E_SECPKG_NOT_FOUND;
if (table->QueryContextAttributes == NULL)
return SEC_E_UNSUPPORTED_FUNCTION;
status = table->QueryContextAttributes(phContext, ulAttribute, pBuffer);
return status;
}
SECURITY_STATUS QuerySecurityContextToken(CTXT_HANDLE* phContext, void* phToken)
{
return SEC_E_OK;
}
SECURITY_STATUS SetContextAttributes(CTXT_HANDLE* phContext, uint32 ulAttribute, void* pBuffer, uint32 cbBuffer)
{
return SEC_E_OK;
}
SECURITY_STATUS RevertSecurityContext(CTXT_HANDLE* phContext)
{
return SEC_E_OK;
}
/* Message Support */
SECURITY_STATUS DecryptMessage(CTXT_HANDLE* phContext, SEC_BUFFER_DESC* pMessage, uint32 MessageSeqNo, uint32* pfQOP)
{
char* Name;
SECURITY_STATUS status;
SECURITY_FUNCTION_TABLE* table;
Name = (char*) sspi_SecureHandleGetUpperPointer(phContext);
if (!Name)
return SEC_E_SECPKG_NOT_FOUND;
table = sspi_GetSecurityFunctionTableByName(Name);
if (!table)
return SEC_E_SECPKG_NOT_FOUND;
if (table->DecryptMessage == NULL)
return SEC_E_UNSUPPORTED_FUNCTION;
status = table->DecryptMessage(phContext, pMessage, MessageSeqNo, pfQOP);
return status;
}
SECURITY_STATUS EncryptMessage(CTXT_HANDLE* phContext, uint32 fQOP, SEC_BUFFER_DESC* pMessage, uint32 MessageSeqNo)
{
char* Name;
SECURITY_STATUS status;
SECURITY_FUNCTION_TABLE* table;
Name = (char*) sspi_SecureHandleGetUpperPointer(phContext);
if (!Name)
return SEC_E_SECPKG_NOT_FOUND;
table = sspi_GetSecurityFunctionTableByName(Name);
if (!table)
return SEC_E_SECPKG_NOT_FOUND;
if (table->EncryptMessage == NULL)
return SEC_E_UNSUPPORTED_FUNCTION;
status = table->EncryptMessage(phContext, fQOP, pMessage, MessageSeqNo);
return status;
}
SECURITY_STATUS MakeSignature(CTXT_HANDLE* phContext, uint32 fQOP, SEC_BUFFER_DESC* pMessage, uint32 MessageSeqNo)
{
char* Name;
SECURITY_STATUS status;
SECURITY_FUNCTION_TABLE* table;
Name = (char*) sspi_SecureHandleGetUpperPointer(phContext);
if (!Name)
return SEC_E_SECPKG_NOT_FOUND;
table = sspi_GetSecurityFunctionTableByName(Name);
if (!table)
return SEC_E_SECPKG_NOT_FOUND;
if (table->MakeSignature == NULL)
return SEC_E_UNSUPPORTED_FUNCTION;
status = table->MakeSignature(phContext, fQOP, pMessage, MessageSeqNo);
return status;
}
SECURITY_STATUS VerifySignature(CTXT_HANDLE* phContext, SEC_BUFFER_DESC* pMessage, uint32 MessageSeqNo, uint32* pfQOP)
{
char* Name;
SECURITY_STATUS status;
SECURITY_FUNCTION_TABLE* table;
Name = (char*) sspi_SecureHandleGetUpperPointer(phContext);
if (!Name)
return SEC_E_SECPKG_NOT_FOUND;
table = sspi_GetSecurityFunctionTableByName(Name);
if (!table)
return SEC_E_SECPKG_NOT_FOUND;
if (table->VerifySignature == NULL)
return SEC_E_UNSUPPORTED_FUNCTION;
status = table->VerifySignature(phContext, pMessage, MessageSeqNo, pfQOP);
return status;
}
const SECURITY_FUNCTION_TABLE SSPI_SECURITY_FUNCTION_TABLE =
{
1, /* dwVersion */
EnumerateSecurityPackages, /* EnumerateSecurityPackages */
NULL, /* Reserved1 */
QueryCredentialsAttributes, /* QueryCredentialsAttributes */
AcquireCredentialsHandle, /* AcquireCredentialsHandle */
FreeCredentialsHandle, /* FreeCredentialsHandle */
NULL, /* Reserved2 */
InitializeSecurityContext, /* InitializeSecurityContext */
AcceptSecurityContext, /* AcceptSecurityContext */
CompleteAuthToken, /* CompleteAuthToken */
DeleteSecurityContext, /* DeleteSecurityContext */
ApplyControlToken, /* ApplyControlToken */
QueryContextAttributes, /* QueryContextAttributes */
ImpersonateSecurityContext, /* ImpersonateSecurityContext */
RevertSecurityContext, /* RevertSecurityContext */
MakeSignature, /* MakeSignature */
VerifySignature, /* VerifySignature */
FreeContextBuffer, /* FreeContextBuffer */
QuerySecurityPackageInfo, /* QuerySecurityPackageInfo */
NULL, /* Reserved3 */
NULL, /* Reserved4 */
ExportSecurityContext, /* ExportSecurityContext */
ImportSecurityContext, /* ImportSecurityContext */
NULL, /* AddCredentials */
NULL, /* Reserved8 */
QuerySecurityContextToken, /* QuerySecurityContextToken */
EncryptMessage, /* EncryptMessage */
DecryptMessage, /* DecryptMessage */
SetContextAttributes, /* SetContextAttributes */
};