text: /**
   * FreeRDP: A Remote Desktop Protocol Implementation
   * Network Level Authentication (NLA)
   *
   * Copyright 2010-2012 Marc-Andre Moreau <marcandre.moreau@gmail.com>
   * Copyright 2015 Thincast Technologies GmbH
   * Copyright 2015 DI (FH) Martin Haimberger <martin.haimberger@thincast.com>
   * Copyright 2016 Martin Fleisz <martin.fleisz@thincast.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 <time.h>
  
  #ifndef _WIN32
  #include <unistd.h>
  #endif
  
  #include <freerdp/log.h>
  #include <freerdp/crypto/tls.h>
  #include <freerdp/build-config.h>
  #include <freerdp/peer.h>
  
  #include <winpr/crt.h>
  #include <winpr/sam.h>
  #include <winpr/sspi.h>
  #include <winpr/print.h>
  #include <winpr/tchar.h>
  #include <winpr/dsparse.h>
  #include <winpr/library.h>
  #include <winpr/registry.h>
  
  #include "nla.h"
  
  #define TAG FREERDP_TAG("core.nla")
  
  #define SERVER_KEY "Software\\"FREERDP_VENDOR_STRING"\\" \
  	FREERDP_PRODUCT_STRING"\\Server"
  
  /**
   * TSRequest ::= SEQUENCE {
   * 	version    [0] INTEGER,
   * 	negoTokens [1] NegoData OPTIONAL,
   * 	authInfo   [2] OCTET STRING OPTIONAL,
   * 	pubKeyAuth [3] OCTET STRING OPTIONAL,
   * 	errorCode  [4] INTEGER OPTIONAL
   * }
   *
   * NegoData ::= SEQUENCE OF NegoDataItem
   *
   * NegoDataItem ::= SEQUENCE {
   * 	negoToken [0] OCTET STRING
   * }
   *
   * TSCredentials ::= SEQUENCE {
   * 	credType    [0] INTEGER,
   * 	credentials [1] OCTET STRING
   * }
   *
   * TSPasswordCreds ::= SEQUENCE {
   * 	domainName  [0] OCTET STRING,
   * 	userName    [1] OCTET STRING,
   * 	password    [2] OCTET STRING
   * }
   *
   * TSSmartCardCreds ::= SEQUENCE {
   * 	pin        [0] OCTET STRING,
   * 	cspData    [1] TSCspDataDetail,
   * 	userHint   [2] OCTET STRING OPTIONAL,
   * 	domainHint [3] OCTET STRING OPTIONAL
   * }
   *
   * TSCspDataDetail ::= SEQUENCE {
   * 	keySpec       [0] INTEGER,
   * 	cardName      [1] OCTET STRING OPTIONAL,
   * 	readerName    [2] OCTET STRING OPTIONAL,
   * 	containerName [3] OCTET STRING OPTIONAL,
   * 	cspName       [4] OCTET STRING OPTIONAL
   * }
   *
   */
  
  #define NLA_PKG_NAME	NEGO_SSP_NAME
  
  #define TERMSRV_SPN_PREFIX	"TERMSRV/"
  
  static BOOL nla_send(rdpNla* nla);
  static int nla_recv(rdpNla* nla);
  static void nla_buffer_print(rdpNla* nla);
  static void nla_buffer_free(rdpNla* nla);
  static SECURITY_STATUS nla_encrypt_public_key_echo(rdpNla* nla);
  static SECURITY_STATUS nla_encrypt_public_key_hash(rdpNla* nla);
  static SECURITY_STATUS nla_decrypt_public_key_echo(rdpNla* nla);
  static SECURITY_STATUS nla_decrypt_public_key_hash(rdpNla* nla);
  static SECURITY_STATUS nla_encrypt_ts_credentials(rdpNla* nla);
  static SECURITY_STATUS nla_decrypt_ts_credentials(rdpNla* nla);
  static BOOL nla_read_ts_password_creds(rdpNla* nla, wStream* s);
  static void nla_identity_free(SEC_WINNT_AUTH_IDENTITY* identity);
  
  #define ber_sizeof_sequence_octet_string(length) ber_sizeof_contextual_tag(ber_sizeof_octet_string(length)) + ber_sizeof_octet_string(length)
  #define ber_write_sequence_octet_string(stream, context, value, length) ber_write_contextual_tag(stream, context, ber_sizeof_octet_string(length), TRUE) + ber_write_octet_string(stream, value, length)
  
  /* CredSSP Client-To-Server Binding Hash\0 */
  static const BYTE ClientServerHashMagic[] =
  {
  	0x43, 0x72, 0x65, 0x64, 0x53, 0x53, 0x50, 0x20,
  	0x43, 0x6C, 0x69, 0x65, 0x6E, 0x74, 0x2D, 0x54,
  	0x6F, 0x2D, 0x53, 0x65, 0x72, 0x76, 0x65, 0x72,
  	0x20, 0x42, 0x69, 0x6E, 0x64, 0x69, 0x6E, 0x67,
  	0x20, 0x48, 0x61, 0x73, 0x68, 0x00
  };
  
  /* CredSSP Server-To-Client Binding Hash\0 */
  static const BYTE ServerClientHashMagic[] =
  {
  	0x43, 0x72, 0x65, 0x64, 0x53, 0x53, 0x50, 0x20,
  	0x53, 0x65, 0x72, 0x76, 0x65, 0x72, 0x2D, 0x54,
  	0x6F, 0x2D, 0x43, 0x6C, 0x69, 0x65, 0x6E, 0x74,
  	0x20, 0x42, 0x69, 0x6E, 0x64, 0x69, 0x6E, 0x67,
  	0x20, 0x48, 0x61, 0x73, 0x68, 0x00
  };
  
  static const UINT32 NonceLength = 32;
  
  void nla_identity_free(SEC_WINNT_AUTH_IDENTITY* identity)
  {
  	if (identity)
  	{
  		/* Password authentication */
  		if (identity->User)
  		{
  			memset(identity->User, 0, identity->UserLength * 2);
  			free(identity->User);
  		}
  
  		if (identity->Password)
  		{
  			memset(identity->Password, 0, identity->PasswordLength * 2);
  			free(identity->Password);
  		}
  
  		if (identity->Domain)
  		{
  			memset(identity->Domain, 0, identity->DomainLength * 2);
  			free(identity->Domain);
  		}
  	}
  
  	free(identity);
  }
  
  /**
   * Initialize NTLM/Kerberos SSP authentication module (client).
   * @param credssp
   */
  
  static int nla_client_init(rdpNla* nla)
  {
  	char* spn;
  	size_t length;
  	rdpTls* tls = NULL;
  	BOOL PromptPassword = FALSE;
  	freerdp* instance = nla->instance;
  	rdpSettings* settings = nla->settings;
  	WINPR_SAM* sam;
  	WINPR_SAM_ENTRY* entry;
  	nla->state = NLA_STATE_INITIAL;
  
  	if (settings->RestrictedAdminModeRequired)
  		settings->DisableCredentialsDelegation = TRUE;
  
  	if ((!settings->Username) || (!strlen(settings->Username))
  	    || (((!settings->Password) || (!strlen(settings->Password)))
  	        && (!settings->RedirectionPassword)))
  	{
  		PromptPassword = TRUE;
  	}
  
  	if (PromptPassword && settings->Username && strlen(settings->Username))
  	{
  		sam = SamOpen(NULL, TRUE);
  
  		if (sam)
  		{
  			entry = SamLookupUserA(sam, settings->Username, strlen(settings->Username), NULL, 0);
  
  			if (entry)
  			{
  				/**
  				 * The user could be found in SAM database.
  				 * Use entry in SAM database later instead of prompt
  				 */
  				PromptPassword = FALSE;
  				SamFreeEntry(sam, entry);
  			}
  
  			SamClose(sam);
  		}
  	}
  
  #ifndef _WIN32
  
  	if (PromptPassword)
  	{
  		if (settings->RestrictedAdminModeRequired)
  		{
  			if ((settings->PasswordHash) && (strlen(settings->PasswordHash) > 0))
  				PromptPassword = FALSE;
  		}
  	}
  
  #endif
  
  	if (PromptPassword)
  	{
  		if (instance->Authenticate)
  		{
  			BOOL proceed = instance->Authenticate(instance,
  			                                      &settings->Username, &settings->Password, &settings->Domain);
  
  			if (!proceed)
  			{
  				freerdp_set_last_error(instance->context, FREERDP_ERROR_CONNECT_CANCELLED);
  				return 0;
  			}
  		}
  	}
  
  	if (!settings->Username)
  	{
  		nla_identity_free(nla->identity);
  		nla->identity = NULL;
  	}
  	else
  	{
  		if (settings->RedirectionPassword && settings->RedirectionPasswordLength > 0)
  		{
  			if (sspi_SetAuthIdentityWithUnicodePassword(nla->identity, settings->Username, settings->Domain,
  			        (UINT16*) settings->RedirectionPassword,
  			        settings->RedirectionPasswordLength / sizeof(WCHAR) - 1) < 0)
  				return -1;
  		}
  		else
  		{
  			if (sspi_SetAuthIdentity(nla->identity, settings->Username, settings->Domain,
  			                         settings->Password) < 0)
  				return -1;
  		}
  	}
  
  #ifndef _WIN32
  	{
  		SEC_WINNT_AUTH_IDENTITY* identity = nla->identity;
  
  		if (!identity)
  		{
  			WLog_ERR(TAG, "NLA identity=%p", (void*) identity);
  			return -1;
  		}
  
  		if (settings->RestrictedAdminModeRequired)
  		{
  			if (settings->PasswordHash)
  			{
  				if (strlen(settings->PasswordHash) == 32)
  				{
  					free(identity->Password);
  					identity->PasswordLength = ConvertToUnicode(CP_UTF8, 0,
  					                           settings->PasswordHash, -1, &identity->Password, 0) - 1;
  					/**
  					 * Multiply password hash length by 64 to obtain a length exceeding
  					 * the maximum (256) and use it this for hash identification in WinPR.
  					 */
  					identity->PasswordLength = 32 * 64; /* 2048 */
  				}
  			}
  		}
  	}
  #endif
  	tls = nla->transport->tls;
  
  	if (!tls)
  	{
  		WLog_ERR(TAG, "Unknown NLA transport layer");
  		return -1;
  	}
  
  	if (!sspi_SecBufferAlloc(&nla->PublicKey, tls->PublicKeyLength))
  	{
  		WLog_ERR(TAG, "Failed to allocate sspi secBuffer");
  		return -1;
  	}
  
  	CopyMemory(nla->PublicKey.pvBuffer, tls->PublicKey, tls->PublicKeyLength);
  	length = sizeof(TERMSRV_SPN_PREFIX) + strlen(settings->ServerHostname);
  	spn = (SEC_CHAR*) malloc(length + 1);
  
  	if (!spn)
  		return -1;
  
  	sprintf(spn, "%s%s", TERMSRV_SPN_PREFIX, settings->ServerHostname);
  #ifdef UNICODE
  	nla->ServicePrincipalName = NULL;
  	ConvertToUnicode(CP_UTF8, 0, spn, -1, &nla->ServicePrincipalName, 0);
  	free(spn);
  #else
  	nla->ServicePrincipalName = spn;
  #endif
  	nla->table = InitSecurityInterfaceEx(0);
  #ifdef WITH_GSSAPI /* KERBEROS SSP */
  	nla->status = nla->table->QuerySecurityPackageInfo(KERBEROS_SSP_NAME, &nla->pPackageInfo);
  
  	if (nla->status != SEC_E_OK)
  	{
  		WLog_ERR(TAG, "QuerySecurityPackageInfo status %s [0x%08"PRIX32"]",
  		         GetSecurityStatusString(nla->status), nla->status);
  		return -1;
  	}
  
  #else /* NTLM SSP */
  	nla->status = nla->table->QuerySecurityPackageInfo(NLA_PKG_NAME, &nla->pPackageInfo);
  
  	if (nla->status != SEC_E_OK)
  	{
  		WLog_ERR(TAG, "QuerySecurityPackageInfo status %s [0x%08"PRIX32"]",
  		         GetSecurityStatusString(nla->status), nla->status);
  		return -1;
  	}
  
  #endif
  	nla->cbMaxToken = nla->pPackageInfo->cbMaxToken;
  	nla->packageName = nla->pPackageInfo->Name;
  	WLog_DBG(TAG, "%s %"PRIu32" : packageName=%ls ; cbMaxToken=%d", __FUNCTION__, __LINE__,
  	         nla->packageName, nla->cbMaxToken);
  	nla->status = nla->table->AcquireCredentialsHandle(NULL, NLA_PKG_NAME,
  	              SECPKG_CRED_OUTBOUND, NULL, nla->identity, NULL, NULL, &nla->credentials,
  	              &nla->expiration);
  
  	if (nla->status != SEC_E_OK)
  	{
  		WLog_ERR(TAG, "AcquireCredentialsHandle status %s [0x%08"PRIX32"]",
  		         GetSecurityStatusString(nla->status), nla->status);
  		return -1;
  	}
  
  	nla->haveContext = FALSE;
  	nla->haveInputBuffer = FALSE;
  	nla->havePubKeyAuth = FALSE;
  	ZeroMemory(&nla->inputBuffer, sizeof(SecBuffer));
  	ZeroMemory(&nla->outputBuffer, sizeof(SecBuffer));
  	ZeroMemory(&nla->ContextSizes, sizeof(SecPkgContext_Sizes));
  	/*
  	 * from tspkg.dll: 0x00000132
  	 * ISC_REQ_MUTUAL_AUTH
  	 * ISC_REQ_CONFIDENTIALITY
  	 * ISC_REQ_USE_SESSION_KEY
  	 * ISC_REQ_ALLOCATE_MEMORY
  	 */
  	nla->fContextReq = ISC_REQ_MUTUAL_AUTH | ISC_REQ_CONFIDENTIALITY | ISC_REQ_USE_SESSION_KEY;
  	return 1;
  }
  
  int nla_client_begin(rdpNla* nla)
  {
  	if (nla_client_init(nla) < 1)
  		return -1;
  
  	if (nla->state != NLA_STATE_INITIAL)
  		return -1;
  
  	nla->outputBufferDesc.ulVersion = SECBUFFER_VERSION;
  	nla->outputBufferDesc.cBuffers = 1;
  	nla->outputBufferDesc.pBuffers = &nla->outputBuffer;
  	nla->outputBuffer.BufferType = SECBUFFER_TOKEN;
  	nla->outputBuffer.cbBuffer = nla->cbMaxToken;
  	nla->outputBuffer.pvBuffer = malloc(nla->outputBuffer.cbBuffer);
  
  	if (!nla->outputBuffer.pvBuffer)
  		return -1;
  
  	nla->status = nla->table->InitializeSecurityContext(&nla->credentials,
  	              NULL, nla->ServicePrincipalName, nla->fContextReq, 0,
  	              SECURITY_NATIVE_DREP, NULL, 0, &nla->context,
  	              &nla->outputBufferDesc, &nla->pfContextAttr, &nla->expiration);
  	WLog_VRB(TAG, " InitializeSecurityContext status %s [0x%08"PRIX32"]",
  	         GetSecurityStatusString(nla->status), nla->status);
  
  	/* Handle kerberos context initialization failure.
  	 * After kerberos failed initialize NTLM context */
  	if (nla->status == SEC_E_NO_CREDENTIALS)
  	{
  		nla->status = nla->table->InitializeSecurityContext(&nla->credentials,
  		              NULL, nla->ServicePrincipalName, nla->fContextReq, 0,
  		              SECURITY_NATIVE_DREP, NULL, 0, &nla->context,
  		              &nla->outputBufferDesc, &nla->pfContextAttr, &nla->expiration);
  		WLog_VRB(TAG, " InitializeSecurityContext status %s [0x%08"PRIX32"]",
  		         GetSecurityStatusString(nla->status), nla->status);
  
  		if (nla->status)
  		{
  			SECURITY_STATUS status = nla->table->QuerySecurityPackageInfo(NTLM_SSP_NAME, &nla->pPackageInfo);
  
  			if (status != SEC_E_OK)
  			{
  				WLog_ERR(TAG, "QuerySecurityPackageInfo status %s [0x%08"PRIX32"]",
  				         GetSecurityStatusString(nla->status), status);
  				return -1;
  			}
  
  			nla->cbMaxToken = nla->pPackageInfo->cbMaxToken;
  			nla->packageName = nla->pPackageInfo->Name;
  		}
  	}
  
  	if ((nla->status == SEC_I_COMPLETE_AND_CONTINUE) || (nla->status == SEC_I_COMPLETE_NEEDED))
  	{
  		if (nla->table->CompleteAuthToken)
  		{
  			SECURITY_STATUS status;
  			status = nla->table->CompleteAuthToken(&nla->context, &nla->outputBufferDesc);
  
  			if (status != SEC_E_OK)
  			{
  				WLog_WARN(TAG, "CompleteAuthToken status %s [0x%08"PRIX32"]",
  				          GetSecurityStatusString(status), status);
  				return -1;
  			}
  		}
  
  		if (nla->status == SEC_I_COMPLETE_NEEDED)
  			nla->status = SEC_E_OK;
  		else if (nla->status == SEC_I_COMPLETE_AND_CONTINUE)
  			nla->status = SEC_I_CONTINUE_NEEDED;
  	}
  
  	if (nla->status != SEC_I_CONTINUE_NEEDED)
  		return -1;
  
  	if (nla->outputBuffer.cbBuffer < 1)
  		return -1;
  
  	nla->negoToken.pvBuffer = nla->outputBuffer.pvBuffer;
  	nla->negoToken.cbBuffer = nla->outputBuffer.cbBuffer;
  	WLog_DBG(TAG, "Sending Authentication Token");
  	winpr_HexDump(TAG, WLOG_DEBUG, nla->negoToken.pvBuffer, nla->negoToken.cbBuffer);
  
  	if (!nla_send(nla))
  	{
  		nla_buffer_free(nla);
  		return -1;
  	}
  
  	nla_buffer_free(nla);
  	nla->state = NLA_STATE_NEGO_TOKEN;
  	return 1;
  }
  
  static int nla_client_recv(rdpNla* nla)
  {
  	int status = -1;
  
  	if (nla->state == NLA_STATE_NEGO_TOKEN)
  	{
  		nla->inputBufferDesc.ulVersion = SECBUFFER_VERSION;
  		nla->inputBufferDesc.cBuffers = 1;
  		nla->inputBufferDesc.pBuffers = &nla->inputBuffer;
  		nla->inputBuffer.BufferType = SECBUFFER_TOKEN;
  		nla->inputBuffer.pvBuffer = nla->negoToken.pvBuffer;
  		nla->inputBuffer.cbBuffer = nla->negoToken.cbBuffer;
  		nla->outputBufferDesc.ulVersion = SECBUFFER_VERSION;
  		nla->outputBufferDesc.cBuffers = 1;
  		nla->outputBufferDesc.pBuffers = &nla->outputBuffer;
  		nla->outputBuffer.BufferType = SECBUFFER_TOKEN;
  		nla->outputBuffer.cbBuffer = nla->cbMaxToken;
  		nla->outputBuffer.pvBuffer = malloc(nla->outputBuffer.cbBuffer);
  
  		if (!nla->outputBuffer.pvBuffer)
  			return -1;
  
  		nla->status = nla->table->InitializeSecurityContext(&nla->credentials,
  		              &nla->context, nla->ServicePrincipalName, nla->fContextReq, 0,
  		              SECURITY_NATIVE_DREP, &nla->inputBufferDesc,
  		              0, &nla->context, &nla->outputBufferDesc, &nla->pfContextAttr, &nla->expiration);
  		WLog_VRB(TAG, "InitializeSecurityContext  %s [0x%08"PRIX32"]",
  		         GetSecurityStatusString(nla->status), nla->status);
  		free(nla->inputBuffer.pvBuffer);
  		nla->inputBuffer.pvBuffer = NULL;
  
  		if ((nla->status == SEC_I_COMPLETE_AND_CONTINUE) || (nla->status == SEC_I_COMPLETE_NEEDED))
  		{
  			if (nla->table->CompleteAuthToken)
  			{
  				SECURITY_STATUS status;
  				status = nla->table->CompleteAuthToken(&nla->context, &nla->outputBufferDesc);
  
  				if (status != SEC_E_OK)
  				{
  					WLog_WARN(TAG, "CompleteAuthToken status %s [0x%08"PRIX32"]",
  					          GetSecurityStatusString(status), status);
  					return -1;
  				}
  			}
  
  			if (nla->status == SEC_I_COMPLETE_NEEDED)
  				nla->status = SEC_E_OK;
  			else if (nla->status == SEC_I_COMPLETE_AND_CONTINUE)
  				nla->status = SEC_I_CONTINUE_NEEDED;
  		}
  
  		if (nla->status == SEC_E_OK)
  		{
  			nla->havePubKeyAuth = TRUE;
  			nla->status = nla->table->QueryContextAttributes(&nla->context, SECPKG_ATTR_SIZES,
  			              &nla->ContextSizes);
  
  			if (nla->status != SEC_E_OK)
  			{
  				WLog_ERR(TAG, "QueryContextAttributes SECPKG_ATTR_SIZES failure %s [0x%08"PRIX32"]",
  				         GetSecurityStatusString(nla->status), nla->status);
  				return -1;
  			}
  
  			if (nla->peerVersion < 5)
  				nla->status = nla_encrypt_public_key_echo(nla);
  			else
  				nla->status = nla_encrypt_public_key_hash(nla);
  
  			if (nla->status != SEC_E_OK)
  				return -1;
  		}
  
  		nla->negoToken.pvBuffer = nla->outputBuffer.pvBuffer;
  		nla->negoToken.cbBuffer = nla->outputBuffer.cbBuffer;
  		WLog_DBG(TAG, "Sending Authentication Token");
  		winpr_HexDump(TAG, WLOG_DEBUG, nla->negoToken.pvBuffer, nla->negoToken.cbBuffer);
  
  		if (!nla_send(nla))
  		{
  			nla_buffer_free(nla);
  			return -1;
  		}
  
  		nla_buffer_free(nla);
  
  		if (nla->status == SEC_E_OK)
  			nla->state = NLA_STATE_PUB_KEY_AUTH;
  
  		status = 1;
  	}
  	else if (nla->state == NLA_STATE_PUB_KEY_AUTH)
  	{
  		/* Verify Server Public Key Echo */
  		if (nla->peerVersion < 5)
  			nla->status = nla_decrypt_public_key_echo(nla);
  		else
  			nla->status = nla_decrypt_public_key_hash(nla);
  
  		nla_buffer_free(nla);
  
  		if (nla->status != SEC_E_OK)
  		{
  			WLog_ERR(TAG, "Could not verify public key echo %s [0x%08"PRIX32"]",
  			         GetSecurityStatusString(nla->status), nla->status);
  			return -1;
  		}
  
  		/* Send encrypted credentials */
  		nla->status = nla_encrypt_ts_credentials(nla);
  
  		if (nla->status != SEC_E_OK)
  		{
  			WLog_ERR(TAG, "nla_encrypt_ts_credentials status %s [0x%08"PRIX32"]",
  			         GetSecurityStatusString(nla->status), nla->status);
  			return -1;
  		}
  
  		if (!nla_send(nla))
  		{
  			nla_buffer_free(nla);
  			return -1;
  		}
  
  		nla_buffer_free(nla);
  
  		if (SecIsValidHandle(&nla->credentials))
  		{
  			nla->table->FreeCredentialsHandle(&nla->credentials);
  			SecInvalidateHandle(&nla->credentials);
  		}
  
  		if (nla->status != SEC_E_OK)
  		{
  			WLog_ERR(TAG, "FreeCredentialsHandle status %s [0x%08"PRIX32"]",
  			         GetSecurityStatusString(nla->status), nla->status);
  		}
  
  		nla->status = nla->table->FreeContextBuffer(nla->pPackageInfo);
  
  		if (nla->status != SEC_E_OK)
  		{
  			WLog_ERR(TAG, "FreeContextBuffer status %s [0x%08"PRIX32"]",
  			         GetSecurityStatusString(nla->status), nla->status);
  		}
  
  		if (nla->status != SEC_E_OK)
  			return -1;
  
  		nla->state = NLA_STATE_AUTH_INFO;
  		status = 1;
  	}
  
  	return status;
  }
  
  static int nla_client_authenticate(rdpNla* nla)
  {
  	wStream* s;
  	int status;
  	s = Stream_New(NULL, 4096);
  
  	if (!s)
  	{
  		WLog_ERR(TAG, "Stream_New failed!");
  		return -1;
  	}
  
  	if (nla_client_begin(nla) < 1)
  	{
  		Stream_Free(s, TRUE);
  		return -1;
  	}
  
  	while (nla->state < NLA_STATE_AUTH_INFO)
  	{
  		Stream_SetPosition(s, 0);
  		status = transport_read_pdu(nla->transport, s);
  
  		if (status < 0)
  		{
  			WLog_ERR(TAG, "nla_client_authenticate failure");
  			Stream_Free(s, TRUE);
  			return -1;
  		}
  
  		status = nla_recv_pdu(nla, s);
  
  		if (status < 0)
  		{
  			Stream_Free(s, TRUE);
  			return -1;
  		}
  	}
  
  	Stream_Free(s, TRUE);
  	return 1;
  }
  
  /**
   * Initialize NTLMSSP authentication module (server).
   * @param credssp
   */
  
  static int nla_server_init(rdpNla* nla)
  {
  	rdpTls* tls = nla->transport->tls;
  
  	if (!sspi_SecBufferAlloc(&nla->PublicKey, tls->PublicKeyLength))
  	{
  		WLog_ERR(TAG, "Failed to allocate SecBuffer for public key");
  		return -1;
  	}
  
  	CopyMemory(nla->PublicKey.pvBuffer, tls->PublicKey, tls->PublicKeyLength);
  
  	if (nla->SspiModule)
  	{
  		HMODULE hSSPI;
  		INIT_SECURITY_INTERFACE pInitSecurityInterface;
  		hSSPI = LoadLibrary(nla->SspiModule);
  
  		if (!hSSPI)
  		{
  			WLog_ERR(TAG, "Failed to load SSPI module: %s", nla->SspiModule);
  			return -1;
  		}
  
  #ifdef UNICODE
  		pInitSecurityInterface = (INIT_SECURITY_INTERFACE) GetProcAddress(hSSPI, "InitSecurityInterfaceW");
  #else
  		pInitSecurityInterface = (INIT_SECURITY_INTERFACE) GetProcAddress(hSSPI, "InitSecurityInterfaceA");
  #endif
  		nla->table = pInitSecurityInterface();
  	}
  	else
  	{
  		nla->table = InitSecurityInterfaceEx(0);
  	}
  
  	nla->status = nla->table->QuerySecurityPackageInfo(NLA_PKG_NAME, &nla->pPackageInfo);
  
  	if (nla->status != SEC_E_OK)
  	{
  		WLog_ERR(TAG, "QuerySecurityPackageInfo status %s [0x%08"PRIX32"]",
  		         GetSecurityStatusString(nla->status), nla->status);
  		return -1;
  	}
  
  	nla->cbMaxToken = nla->pPackageInfo->cbMaxToken;
  	nla->packageName = nla->pPackageInfo->Name;
  	nla->status = nla->table->AcquireCredentialsHandle(NULL, NLA_PKG_NAME,
  	              SECPKG_CRED_INBOUND, NULL, NULL, NULL, NULL, &nla->credentials, &nla->expiration);
  
  	if (nla->status != SEC_E_OK)
  	{
  		WLog_ERR(TAG, "AcquireCredentialsHandle status %s [0x%08"PRIX32"]",
  		         GetSecurityStatusString(nla->status), nla->status);
  		return -1;
  	}
  
  	nla->haveContext = FALSE;
  	nla->haveInputBuffer = FALSE;
  	nla->havePubKeyAuth = FALSE;
  	ZeroMemory(&nla->inputBuffer, sizeof(SecBuffer));
  	ZeroMemory(&nla->outputBuffer, sizeof(SecBuffer));
  	ZeroMemory(&nla->inputBufferDesc, sizeof(SecBufferDesc));
  	ZeroMemory(&nla->outputBufferDesc, sizeof(SecBufferDesc));
  	ZeroMemory(&nla->ContextSizes, sizeof(SecPkgContext_Sizes));
  	/*
  	 * from tspkg.dll: 0x00000112
  	 * ASC_REQ_MUTUAL_AUTH
  	 * ASC_REQ_CONFIDENTIALITY
  	 * ASC_REQ_ALLOCATE_MEMORY
  	 */
  	nla->fContextReq = 0;
  	nla->fContextReq |= ASC_REQ_MUTUAL_AUTH;
  	nla->fContextReq |= ASC_REQ_CONFIDENTIALITY;
  	nla->fContextReq |= ASC_REQ_CONNECTION;
  	nla->fContextReq |= ASC_REQ_USE_SESSION_KEY;
  	nla->fContextReq |= ASC_REQ_REPLAY_DETECT;
  	nla->fContextReq |= ASC_REQ_SEQUENCE_DETECT;
  	nla->fContextReq |= ASC_REQ_EXTENDED_ERROR;
  	return 1;
  }
  
  /**
   * Authenticate with client using CredSSP (server).
   * @param credssp
   * @return 1 if authentication is successful
   */
  
  static int nla_server_authenticate(rdpNla* nla)
  {
  	if (nla_server_init(nla) < 1)
  		return -1;
  
  	while (TRUE)
  	{
  		/* receive authentication token */
  		nla->inputBufferDesc.ulVersion = SECBUFFER_VERSION;
  		nla->inputBufferDesc.cBuffers = 1;
  		nla->inputBufferDesc.pBuffers = &nla->inputBuffer;
  		nla->inputBuffer.BufferType = SECBUFFER_TOKEN;
  
  		if (nla_recv(nla) < 0)
  			return -1;
  
  		WLog_DBG(TAG, "Receiving Authentication Token");
  		nla_buffer_print(nla);
  		nla->inputBuffer.pvBuffer = nla->negoToken.pvBuffer;
  		nla->inputBuffer.cbBuffer = nla->negoToken.cbBuffer;
  
  		if (nla->negoToken.cbBuffer < 1)
  		{
  			WLog_ERR(TAG, "CredSSP: invalid negoToken!");
  			return -1;
  		}
  
  		nla->outputBufferDesc.ulVersion = SECBUFFER_VERSION;
  		nla->outputBufferDesc.cBuffers = 1;
  		nla->outputBufferDesc.pBuffers = &nla->outputBuffer;
  		nla->outputBuffer.BufferType = SECBUFFER_TOKEN;
  		nla->outputBuffer.cbBuffer = nla->cbMaxToken;
  		nla->outputBuffer.pvBuffer = malloc(nla->outputBuffer.cbBuffer);
  
  		if (!nla->outputBuffer.pvBuffer)
  			return -1;
  
  		nla->status = nla->table->AcceptSecurityContext(&nla->credentials,
  		              nla->haveContext ? &nla->context : NULL,
  		              &nla->inputBufferDesc, nla->fContextReq, SECURITY_NATIVE_DREP, &nla->context,
  		              &nla->outputBufferDesc, &nla->pfContextAttr, &nla->expiration);
  		WLog_VRB(TAG, "AcceptSecurityContext status %s [0x%08"PRIX32"]",
  		         GetSecurityStatusString(nla->status), nla->status);
  		nla->negoToken.pvBuffer = nla->outputBuffer.pvBuffer;
  		nla->negoToken.cbBuffer = nla->outputBuffer.cbBuffer;
  
  		if ((nla->status == SEC_I_COMPLETE_AND_CONTINUE) || (nla->status == SEC_I_COMPLETE_NEEDED))
  		{
  			freerdp_peer* peer = nla->instance->context->peer;
  
  			if (peer->ComputeNtlmHash)
  			{
  				SECURITY_STATUS status;
  				status = nla->table->SetContextAttributes(&nla->context, SECPKG_ATTR_AUTH_NTLM_HASH_CB,
  				         peer->ComputeNtlmHash, 0);
  
  				if (status != SEC_E_OK)
  				{
  					WLog_ERR(TAG, "SetContextAttributesA(hash cb) status %s [0x%08"PRIX32"]",
  					         GetSecurityStatusString(status), status);
  				}
  
  				status = nla->table->SetContextAttributes(&nla->context, SECPKG_ATTR_AUTH_NTLM_HASH_CB_DATA, peer,
  				         0);
  
  				if (status != SEC_E_OK)
  				{
  					WLog_ERR(TAG, "SetContextAttributesA(hash cb data) status %s [0x%08"PRIX32"]",
  					         GetSecurityStatusString(status), status);
  				}
  			}
  			else if (nla->SamFile)
  			{
  				nla->table->SetContextAttributes(&nla->context, SECPKG_ATTR_AUTH_NTLM_SAM_FILE, nla->SamFile,
  				                                 strlen(nla->SamFile) + 1);
  			}
  
  			if (nla->table->CompleteAuthToken)
  			{
  				SECURITY_STATUS status;
  				status = nla->table->CompleteAuthToken(&nla->context, &nla->outputBufferDesc);
  
  				if (status != SEC_E_OK)
  				{
  					WLog_WARN(TAG, "CompleteAuthToken status %s [0x%08"PRIX32"]",
  					          GetSecurityStatusString(status), status);
  					return -1;
  				}
  			}
  
  			if (nla->status == SEC_I_COMPLETE_NEEDED)
  				nla->status = SEC_E_OK;
  			else if (nla->status == SEC_I_COMPLETE_AND_CONTINUE)
  				nla->status = SEC_I_CONTINUE_NEEDED;
  		}
  
  		if (nla->status == SEC_E_OK)
  		{
  			if (nla->outputBuffer.cbBuffer != 0)
  			{
  				if (!nla_send(nla))
  				{
  					nla_buffer_free(nla);
  					return -1;
  				}
  
  				if (nla_recv(nla) < 0)
  					return -1;
  
  				WLog_DBG(TAG, "Receiving pubkey Token");
  				nla_buffer_print(nla);
  			}
  
  			nla->havePubKeyAuth = TRUE;
  			nla->status = nla->table->QueryContextAttributes(&nla->context, SECPKG_ATTR_SIZES,
  			              &nla->ContextSizes);
  
  			if (nla->status != SEC_E_OK)
  			{
  				WLog_ERR(TAG, "QueryContextAttributes SECPKG_ATTR_SIZES failure %s [0x%08"PRIX32"]",
  				         GetSecurityStatusString(nla->status), nla->status);
  				return -1;
  			}
  
  			if (nla->peerVersion < 5)
  				nla->status = nla_decrypt_public_key_echo(nla);
  			else
  				nla->status = nla_decrypt_public_key_hash(nla);
  
  			if (nla->status != SEC_E_OK)
  			{
  				WLog_ERR(TAG, "Error: could not verify client's public key echo %s [0x%08"PRIX32"]",
  				         GetSecurityStatusString(nla->status), nla->status);
  				return -1;
  			}
  
  			sspi_SecBufferFree(&nla->negoToken);
  			nla->negoToken.pvBuffer = NULL;
  			nla->negoToken.cbBuffer = 0;
  
  			if (nla->peerVersion < 5)
  				nla->status = nla_encrypt_public_key_echo(nla);
  			else
  				nla->status = nla_encrypt_public_key_hash(nla);
  
  			if (nla->status != SEC_E_OK)
  				return -1;
  		}
  
  		if ((nla->status != SEC_E_OK) && (nla->status != SEC_I_CONTINUE_NEEDED))
  		{
  			/* Special handling of these specific error codes as NTSTATUS_FROM_WIN32
  			   unfortunately does not map directly to the corresponding NTSTATUS values
  			 */
  			switch (GetLastError())
  			{
  				case ERROR_PASSWORD_MUST_CHANGE:
  					nla->errorCode = STATUS_PASSWORD_MUST_CHANGE;
  					break;
  
  				case ERROR_PASSWORD_EXPIRED:
  					nla->errorCode = STATUS_PASSWORD_EXPIRED;
  					break;
  
  				case ERROR_ACCOUNT_DISABLED:
  					nla->errorCode = STATUS_ACCOUNT_DISABLED;
  					break;
  
  				default:
  					nla->errorCode = NTSTATUS_FROM_WIN32(GetLastError());
  					break;
  			}
  
  			WLog_ERR(TAG, "AcceptSecurityContext status %s [0x%08"PRIX32"]",
  			         GetSecurityStatusString(nla->status), nla->status);
  			nla_send(nla);
  			return -1; /* Access Denied */
  		}
  
  		/* send authentication token */
  		WLog_DBG(TAG, "Sending Authentication Token");
  		nla_buffer_print(nla);
  
  		if (!nla_send(nla))
  		{
  			nla_buffer_free(nla);
  			return -1;
  		}
  
  		nla_buffer_free(nla);
  
  		if (nla->status != SEC_I_CONTINUE_NEEDED)
  			break;
  
  		nla->haveContext = TRUE;
  	}
  
  	/* Receive encrypted credentials */
  
  	if (nla_recv(nla) < 0)
  		return -1;
  
  	nla->status = nla_decrypt_ts_credentials(nla);
  
  	if (nla->status != SEC_E_OK)
  	{
  		WLog_ERR(TAG, "Could not decrypt TSCredentials status %s [0x%08"PRIX32"]",
  		         GetSecurityStatusString(nla->status), nla->status);
  		return -1;
  	}
  
  	nla->status = nla->table->ImpersonateSecurityContext(&nla->context);
  
  	if (nla->status != SEC_E_OK)
  	{
  		WLog_ERR(TAG, "ImpersonateSecurityContext status %s [0x%08"PRIX32"]",
  		         GetSecurityStatusString(nla->status), nla->status);
  		return -1;
  	}
  	else
  	{
  		nla->status = nla->table->RevertSecurityContext(&nla->context);
  
  		if (nla->status != SEC_E_OK)
  		{
  			WLog_ERR(TAG, "RevertSecurityContext status %s [0x%08"PRIX32"]",
  			         GetSecurityStatusString(nla->status), nla->status);
  			return -1;
  		}
  	}
  
  	nla->status = nla->table->FreeContextBuffer(nla->pPackageInfo);
  
  	if (nla->status != SEC_E_OK)
  	{
  		WLog_ERR(TAG, "DeleteSecurityContext status %s [0x%08"PRIX32"]",
  		         GetSecurityStatusString(nla->status), nla->status);
  		return -1;
  	}
  
  	return 1;
  }
  
  /**
   * Authenticate using CredSSP.
   * @param credssp
   * @return 1 if authentication is successful
   */
  
  int nla_authenticate(rdpNla* nla)
  {
  	if (nla->server)
  		return nla_server_authenticate(nla);
  	else
  		return nla_client_authenticate(nla);
  }
  
  static void ap_integer_increment_le(BYTE* number, int size)
  {
  	int index;
  
  	for (index = 0; index < size; index++)
  	{
  		if (number[index] < 0xFF)
  		{
  			number[index]++;
  			break;
  		}
  		else
  		{
  			number[index] = 0;
  			continue;
  		}
  	}
  }
  
  static void ap_integer_decrement_le(BYTE* number, int size)
  {
  	int index;
  
  	for (index = 0; index < size; index++)
  	{
  		if (number[index] > 0)
  		{
  			number[index]--;
  			break;
  		}
  		else
  		{
  			number[index] = 0xFF;
  			continue;
  		}
  	}
  }
  
  SECURITY_STATUS nla_encrypt_public_key_echo(rdpNla* nla)
  {
  	SecBuffer Buffers[2] = { { 0 } };
  	SecBufferDesc Message;
  	SECURITY_STATUS status;
  	ULONG public_key_length;
  	const BOOL krb = (_tcsncmp(nla->packageName, KERBEROS_SSP_NAME, ARRAYSIZE(KERBEROS_SSP_NAME)) == 0);
  	const BOOL nego = (_tcsncmp(nla->packageName, NEGO_SSP_NAME, ARRAYSIZE(NEGO_SSP_NAME)) == 0);
  	const BOOL ntlm = (_tcsncmp(nla->packageName,  NTLM_SSP_NAME, ARRAYSIZE(NTLM_SSP_NAME)) == 0);
  	public_key_length = nla->PublicKey.cbBuffer;
  
  	if (!sspi_SecBufferAlloc(&nla->pubKeyAuth, public_key_length + nla->ContextSizes.cbSecurityTrailer))
  		return SEC_E_INSUFFICIENT_MEMORY;
  
  	if (krb)
  	{
  		Buffers[0].BufferType = SECBUFFER_DATA; /* TLS Public Key */
  		Buffers[0].cbBuffer = public_key_length;
  		Buffers[0].pvBuffer = nla->pubKeyAuth.pvBuffer;
  		CopyMemory(Buffers[0].pvBuffer, nla->PublicKey.pvBuffer, Buffers[0].cbBuffer);
  	}
  	else if (ntlm || nego)
  	{
  		Buffers[0].BufferType = SECBUFFER_TOKEN; /* Signature */
  		Buffers[0].cbBuffer = nla->ContextSizes.cbSecurityTrailer;
  		Buffers[0].pvBuffer = nla->pubKeyAuth.pvBuffer;
  		Buffers[1].BufferType = SECBUFFER_DATA; /* TLS Public Key */
  		Buffers[1].cbBuffer = public_key_length;
  		Buffers[1].pvBuffer = ((BYTE*) nla->pubKeyAuth.pvBuffer) + nla->ContextSizes.cbSecurityTrailer;
  		CopyMemory(Buffers[1].pvBuffer, nla->PublicKey.pvBuffer, Buffers[1].cbBuffer);
  	}
  
  	if (!krb && nla->server)
  	{
  		/* server echos the public key +1 */
  		ap_integer_increment_le((BYTE*) Buffers[1].pvBuffer, Buffers[1].cbBuffer);
  	}
  
  	Message.cBuffers = 2;
  	Message.ulVersion = SECBUFFER_VERSION;
  	Message.pBuffers = (PSecBuffer) &Buffers;
  	status = nla->table->EncryptMessage(&nla->context, 0, &Message, nla->sendSeqNum++);
  
  	if (status != SEC_E_OK)
  	{
  		WLog_ERR(TAG, "EncryptMessage status %s [0x%08"PRIX32"]",
  		         GetSecurityStatusString(status), status);
  		return status;
  	}
  
  	return status;
  }
  
  SECURITY_STATUS nla_encrypt_public_key_hash(rdpNla* nla)
  {
  	SecBuffer Buffers[2] = { { 0 } };
  	SecBufferDesc Message;
  	SECURITY_STATUS status = SEC_E_INTERNAL_ERROR;
  	WINPR_DIGEST_CTX* sha256 = NULL;
  	const BOOL krb = (_tcsncmp(nla->packageName, KERBEROS_SSP_NAME, ARRAYSIZE(KERBEROS_SSP_NAME)) == 0);
  	const ULONG auth_data_length = krb ? WINPR_SHA256_DIGEST_LENGTH :
  	                               (nla->ContextSizes.cbSecurityTrailer
  	                                + WINPR_SHA256_DIGEST_LENGTH);
  	const BYTE* hashMagic = nla->server ? ServerClientHashMagic : ClientServerHashMagic;
  	const size_t hashSize = nla->server ? sizeof(ServerClientHashMagic) : sizeof(ClientServerHashMagic);
  
  	if (!sspi_SecBufferAlloc(&nla->pubKeyAuth, auth_data_length))
  	{
  		status = SEC_E_INSUFFICIENT_MEMORY;
  		goto out;
  	}
  
  	/* generate SHA256 of following data: ClientServerHashMagic, Nonce, SubjectPublicKey */
  	if (!(sha256 = winpr_Digest_New()))
  		goto out;
  
  	if (!winpr_Digest_Init(sha256, WINPR_MD_SHA256))
  		goto out;
  
  	/* include trailing \0 from hashMagic */
  	if (!winpr_Digest_Update(sha256, hashMagic, hashSize))
  		goto out;
  
  	if (!winpr_Digest_Update(sha256, nla->ClientNonce.pvBuffer, nla->ClientNonce.cbBuffer))
  		goto out;
  
  	/* SubjectPublicKey */
  	if (!winpr_Digest_Update(sha256, nla->PublicKey.pvBuffer, nla->PublicKey.cbBuffer))
  		goto out;
  
  	Message.pBuffers = (PSecBuffer)&Buffers;
  	Message.ulVersion = SECBUFFER_VERSION;
  
  	if (krb)
  	{
  		Message.cBuffers = 1;
  		Buffers[0].BufferType = SECBUFFER_DATA; /* SHA256 hash */
  		Buffers[0].cbBuffer = WINPR_SHA256_DIGEST_LENGTH;
  		Buffers[0].pvBuffer = nla->pubKeyAuth.pvBuffer;
  
  		if (!winpr_Digest_Final(sha256, Buffers[0].pvBuffer, Buffers[0].cbBuffer))
  			goto out;
  	}
  	else
  	{
  		Message.cBuffers = 2;
  		Buffers[0].BufferType = SECBUFFER_TOKEN; /* Signature */
  		Buffers[0].cbBuffer = nla->ContextSizes.cbSecurityTrailer;
  		Buffers[0].pvBuffer = nla->pubKeyAuth.pvBuffer;
  		Buffers[1].BufferType = SECBUFFER_DATA; /* SHA256 hash */
  		Buffers[1].cbBuffer = WINPR_SHA256_DIGEST_LENGTH;
  		Buffers[1].pvBuffer = ((BYTE*)nla->pubKeyAuth.pvBuffer) + nla->ContextSizes.cbSecurityTrailer;
  
  		if (!winpr_Digest_Final(sha256, Buffers[1].pvBuffer, Buffers[1].cbBuffer))
  			goto out;
  	}
  
  	/* encrypt message */
  	status = nla->table->EncryptMessage(&nla->context, 0, &Message, nla->sendSeqNum++);
  
  	if (status != SEC_E_OK)
  	{
  		WLog_ERR(TAG, "EncryptMessage status %s [0x%08"PRIX32"]",
  		         GetSecurityStatusString(status), status);
  	}
  
  out:
  	winpr_Digest_Free(sha256);
  	return status;
  }
  
  SECURITY_STATUS nla_decrypt_public_key_echo(rdpNla* nla)
  {
  	ULONG length;
  	BYTE* buffer = NULL;
  	ULONG pfQOP = 0;
  	BYTE* public_key1 = NULL;
  	BYTE* public_key2 = NULL;
  	ULONG public_key_length = 0;
  	int signature_length;
  	SecBuffer Buffers[2] = { { 0 } };
  	SecBufferDesc Message;
  	BOOL krb, ntlm, nego;
  	SECURITY_STATUS status = SEC_E_INVALID_TOKEN;
  
  	if (!nla)
  		goto fail;
  
  	krb = (_tcsncmp(nla->packageName, KERBEROS_SSP_NAME, ARRAYSIZE(KERBEROS_SSP_NAME)) == 0);
  	nego = (_tcsncmp(nla->packageName, NEGO_SSP_NAME, ARRAYSIZE(NEGO_SSP_NAME)) == 0);
  	ntlm = (_tcsncmp(nla->packageName,  NTLM_SSP_NAME, ARRAYSIZE(NTLM_SSP_NAME)) == 0);
  	signature_length = nla->pubKeyAuth.cbBuffer - nla->PublicKey.cbBuffer;
  
  	if ((signature_length < 0) || (signature_length > nla->ContextSizes.cbSecurityTrailer))
  	{
  		WLog_ERR(TAG, "unexpected pubKeyAuth buffer size: %"PRIu32"", nla->pubKeyAuth.cbBuffer);
  		goto fail;
  	}
  
  	if ((nla->PublicKey.cbBuffer + nla->ContextSizes.cbSecurityTrailer) != nla->pubKeyAuth.cbBuffer)
  	{
  		WLog_ERR(TAG, "unexpected pubKeyAuth buffer size: %"PRIu32"", nla->pubKeyAuth.cbBuffer);
  		goto fail;
  	}
  
  	length = nla->pubKeyAuth.cbBuffer;
  	buffer = (BYTE*) malloc(length);
  
  	if (!buffer)
  	{
  		status = SEC_E_INSUFFICIENT_MEMORY;
  		goto fail;
  	}
  
  	if (krb)
  	{
  		CopyMemory(buffer, nla->pubKeyAuth.pvBuffer, length);
  		Buffers[0].BufferType = SECBUFFER_DATA; /* Wrapped and encrypted TLS Public Key */
  		Buffers[0].cbBuffer = length;
  		Buffers[0].pvBuffer = buffer;
  		Message.cBuffers = 1;
  		Message.ulVersion = SECBUFFER_VERSION;
  		Message.pBuffers = (PSecBuffer) &Buffers;
  	}
  	else if (ntlm || nego)
  	{
  		CopyMemory(buffer, nla->pubKeyAuth.pvBuffer, length);
  		public_key_length = nla->PublicKey.cbBuffer;
  		Buffers[0].BufferType = SECBUFFER_TOKEN; /* Signature */
  		Buffers[0].cbBuffer = signature_length;
  		Buffers[0].pvBuffer = buffer;
  		Buffers[1].BufferType = SECBUFFER_DATA; /* Encrypted TLS Public Key */
  		Buffers[1].cbBuffer = length - signature_length;
  		Buffers[1].pvBuffer = buffer + signature_length;
  		Message.cBuffers = 2;
  		Message.ulVersion = SECBUFFER_VERSION;
  		Message.pBuffers = (PSecBuffer) &Buffers;
  	}
  
  	status = nla->table->DecryptMessage(&nla->context, &Message, nla->recvSeqNum++, &pfQOP);
  
  	if (status != SEC_E_OK)
  	{
  		WLog_ERR(TAG, "DecryptMessage failure %s [%08"PRIX32"]",
  		         GetSecurityStatusString(status), status);
  		goto fail;
  	}
  
  	if (krb)
  	{
  		public_key1 = public_key2 = (BYTE*) nla->pubKeyAuth.pvBuffer ;
  		public_key_length = length;
  	}
  	else if (ntlm || nego)
  	{
  		public_key1 = (BYTE*) nla->PublicKey.pvBuffer;
  		public_key2 = (BYTE*) Buffers[1].pvBuffer;
  	}
  
  	if (!nla->server)
  	{
  		/* server echos the public key +1 */
  		ap_integer_decrement_le(public_key2, public_key_length);
  	}
  
  	if (!public_key1 || !public_key2 || memcmp(public_key1, public_key2, public_key_length) != 0)
  	{
  		WLog_ERR(TAG, "Could not verify server's public key echo");
  		WLog_ERR(TAG, "Expected (length = %d):", public_key_length);
  		winpr_HexDump(TAG, WLOG_ERROR, public_key1, public_key_length);
  		WLog_ERR(TAG, "Actual (length = %d):", public_key_length);
  		winpr_HexDump(TAG, WLOG_ERROR, public_key2, public_key_length);
  		status = SEC_E_MESSAGE_ALTERED; /* DO NOT SEND CREDENTIALS! */
  		goto fail;
  	}
  
  	status = SEC_E_OK;
  fail:
  	free(buffer);
  	return status;
  }
  
  SECURITY_STATUS nla_decrypt_public_key_hash(rdpNla* nla)
  {
  	unsigned long length;
  	BYTE* buffer = NULL;
  	ULONG pfQOP = 0;
  	int signature_length;
  	SecBuffer Buffers[2] = { { 0 } };
  	SecBufferDesc Message;
  	WINPR_DIGEST_CTX* sha256 = NULL;
  	BYTE serverClientHash[WINPR_SHA256_DIGEST_LENGTH];
  	SECURITY_STATUS status = SEC_E_INVALID_TOKEN;
  	const BOOL krb = (_tcsncmp(nla->packageName, KERBEROS_SSP_NAME, ARRAYSIZE(KERBEROS_SSP_NAME)) == 0);
  	const BYTE* hashMagic = nla->server ? ClientServerHashMagic : ServerClientHashMagic;
  	const size_t hashSize = nla->server ? sizeof(ClientServerHashMagic) : sizeof(ServerClientHashMagic);
  	signature_length = nla->pubKeyAuth.cbBuffer - WINPR_SHA256_DIGEST_LENGTH;
  
  	if ((signature_length < 0) || (signature_length > (int)nla->ContextSizes.cbSecurityTrailer))
  	{
  		WLog_ERR(TAG, "unexpected pubKeyAuth buffer size: %"PRIu32"", nla->pubKeyAuth.cbBuffer);
  		goto fail;
  	}
  
  	if ((nla->ContextSizes.cbSecurityTrailer + WINPR_SHA256_DIGEST_LENGTH) != nla->pubKeyAuth.cbBuffer)
  	{
  		WLog_ERR(TAG, "unexpected pubKeyAuth buffer size: %"PRIu32"", (int)nla->pubKeyAuth.cbBuffer);
  		goto fail;
  	}
  
  	length = nla->pubKeyAuth.cbBuffer;
  	buffer = (BYTE*)malloc(length);
  
  	if (!buffer)
  	{
  		status = SEC_E_INSUFFICIENT_MEMORY;
  		goto fail;
  	}
  
  	if (krb)
  	{
  		CopyMemory(buffer, nla->pubKeyAuth.pvBuffer, length);
  		Buffers[0].BufferType = SECBUFFER_DATA; /* Encrypted Hash */
  		Buffers[0].cbBuffer = length;
  		Buffers[0].pvBuffer = buffer;
  		Message.cBuffers = 1;
  		Message.ulVersion = SECBUFFER_VERSION;
  		Message.pBuffers = (PSecBuffer)&Buffers;
  	}
  	else
  	{
  		CopyMemory(buffer, nla->pubKeyAuth.pvBuffer, length);
  		Buffers[0].BufferType = SECBUFFER_TOKEN; /* Signature */
  		Buffers[0].cbBuffer = signature_length;
  		Buffers[0].pvBuffer = buffer;
  		Buffers[1].BufferType = SECBUFFER_DATA; /* Encrypted Hash */
  		Buffers[1].cbBuffer = WINPR_SHA256_DIGEST_LENGTH;
  		Buffers[1].pvBuffer = buffer + signature_length;
  		Message.cBuffers = 2;
  		Message.ulVersion = SECBUFFER_VERSION;
  		Message.pBuffers = (PSecBuffer)&Buffers;
  	}
  
  	status = nla->table->DecryptMessage(&nla->context, &Message, nla->recvSeqNum++, &pfQOP);
  
  	if (status != SEC_E_OK)
  	{
  		WLog_ERR(TAG, "DecryptMessage failure %s [%08"PRIX32"]",
  		         GetSecurityStatusString(status), status);
  		goto fail;
  	}
  
  	/* generate SHA256 of following data: ServerClientHashMagic, Nonce, SubjectPublicKey */
  	if (!(sha256 = winpr_Digest_New()))
  		goto fail;
  
  	if (!winpr_Digest_Init(sha256, WINPR_MD_SHA256))
  		goto fail;
  
  	/* include trailing \0 from hashMagic */
  	if (!winpr_Digest_Update(sha256, hashMagic, hashSize))
  		goto fail;
  
  	if (!winpr_Digest_Update(sha256, nla->ClientNonce.pvBuffer, nla->ClientNonce.cbBuffer))
  		goto fail;
  
  	/* SubjectPublicKey */
  	if (!winpr_Digest_Update(sha256, nla->PublicKey.pvBuffer, nla->PublicKey.cbBuffer))
  		goto fail;
  
  	if (!winpr_Digest_Final(sha256, serverClientHash, sizeof(serverClientHash)))
  		goto fail;
  
  	/* verify hash */
  	if (memcmp(serverClientHash, Buffers[krb ? 0 : 1].pvBuffer, WINPR_SHA256_DIGEST_LENGTH) != 0)
  	{
  		WLog_ERR(TAG, "Could not verify server's hash");
  		status = SEC_E_MESSAGE_ALTERED; /* DO NOT SEND CREDENTIALS! */
  		goto fail;
  	}
  
  	status = SEC_E_OK;
  fail:
  	free(buffer);
  	winpr_Digest_Free(sha256);
  	return status;
  }
  
  static size_t nla_sizeof_ts_password_creds(rdpNla* nla)
  {
  	size_t length = 0;
  
  	if (nla->identity)
  	{
  		length += ber_sizeof_sequence_octet_string(nla->identity->DomainLength * 2);
  		length += ber_sizeof_sequence_octet_string(nla->identity->UserLength * 2);
  		length += ber_sizeof_sequence_octet_string(nla->identity->PasswordLength * 2);
  	}
  
  	return length;
  }
  
  static size_t nla_sizeof_ts_credentials(rdpNla* nla)
  {
  	size_t size = 0;
  	size += ber_sizeof_integer(1);
  	size += ber_sizeof_contextual_tag(ber_sizeof_integer(1));
  	size += ber_sizeof_sequence_octet_string(ber_sizeof_sequence(nla_sizeof_ts_password_creds(nla)));
  	return size;
  }
  
  BOOL nla_read_ts_password_creds(rdpNla* nla, wStream* s)
  {
  	size_t length;
  
  	if (!nla->identity)
  	{
  		WLog_ERR(TAG, "nla->identity is NULL!");
  		return FALSE;
  	}
  
  	/* TSPasswordCreds (SEQUENCE)
  	 * Initialise to default values. */
  	nla->identity->Flags = SEC_WINNT_AUTH_IDENTITY_UNICODE;
  	nla->identity->UserLength = (UINT32) 0;
  	nla->identity->User = NULL;
  	nla->identity->DomainLength = (UINT32) 0;
  	nla->identity->Domain = NULL;
  	nla->identity->Password = NULL;
  	nla->identity->PasswordLength = (UINT32) 0;
  
  	if (!ber_read_sequence_tag(s, &length))
  		return FALSE;
  
  	/* The sequence is empty, return early,
  	 * TSPasswordCreds (SEQUENCE) is optional. */
  	if (length == 0)
  		return TRUE;
  
  	/* [0] domainName (OCTET STRING) */
  	if (!ber_read_contextual_tag(s, 0, &length, TRUE) ||
  	    !ber_read_octet_string_tag(s, &length))
  	{
  		return FALSE;
  	}
  
  	nla->identity->DomainLength = (UINT32) length;
  
  	if (nla->identity->DomainLength > 0)
  	{
  		nla->identity->Domain = (UINT16*) malloc(length);
  
  		if (!nla->identity->Domain)
  			return FALSE;
  
  		CopyMemory(nla->identity->Domain, Stream_Pointer(s), nla->identity->DomainLength);
  		Stream_Seek(s, nla->identity->DomainLength);
  		nla->identity->DomainLength /= 2;
  	}
  
  	/* [1] userName (OCTET STRING) */
  	if (!ber_read_contextual_tag(s, 1, &length, TRUE) ||
  	    !ber_read_octet_string_tag(s, &length))
  	{
  		return FALSE;
  	}
  
  	nla->identity->UserLength = (UINT32) length;
  
  	if (nla->identity->UserLength > 0)
  	{
  		nla->identity->User = (UINT16*) malloc(length);
  
  		if (!nla->identity->User)
  			return FALSE;
  
  		CopyMemory(nla->identity->User, Stream_Pointer(s), nla->identity->UserLength);
  		Stream_Seek(s, nla->identity->UserLength);
  		nla->identity->UserLength /= 2;
  	}
  
  	/* [2] password (OCTET STRING) */
  	if (!ber_read_contextual_tag(s, 2, &length, TRUE) ||
  	    !ber_read_octet_string_tag(s, &length))
  	{
  		return FALSE;
  	}
  
  	nla->identity->PasswordLength = (UINT32) length;
  
  	if (nla->identity->PasswordLength > 0)
  	{
  		nla->identity->Password = (UINT16*) malloc(length);
  
  		if (!nla->identity->Password)
  			return FALSE;
  
  		CopyMemory(nla->identity->Password, Stream_Pointer(s), nla->identity->PasswordLength);
  		Stream_Seek(s, nla->identity->PasswordLength);
  		nla->identity->PasswordLength /= 2;
  	}
  
  	return TRUE;
  }
  
  static size_t nla_write_ts_password_creds(rdpNla* nla, wStream* s)
  {
  	size_t size = 0;
  	size_t innerSize = nla_sizeof_ts_password_creds(nla);
  	/* TSPasswordCreds (SEQUENCE) */
  	size += ber_write_sequence_tag(s, innerSize);
  
  	if (nla->identity)
  	{
  		/* [0] domainName (OCTET STRING) */
  		size += ber_write_sequence_octet_string(
  		            s, 0, (BYTE*) nla->identity->Domain,
  		            nla->identity->DomainLength * 2);
  		/* [1] userName (OCTET STRING) */
  		size += ber_write_sequence_octet_string(
  		            s, 1, (BYTE*) nla->identity->User,
  		            nla->identity->UserLength * 2);
  		/* [2] password (OCTET STRING) */
  		size += ber_write_sequence_octet_string(
  		            s, 2, (BYTE*) nla->identity->Password,
  		            nla->identity->PasswordLength * 2);
  	}
  
  	return size;
  }
  
  static BOOL nla_read_ts_credentials(rdpNla* nla, PSecBuffer ts_credentials)
  {
  	wStream* s;
  	size_t length;
  	size_t ts_password_creds_length = 0;
  	BOOL ret;
  
  	if (!ts_credentials || !ts_credentials->pvBuffer)
  		return FALSE;
  
  	s = Stream_New(ts_credentials->pvBuffer, ts_credentials->cbBuffer);
  
  	if (!s)
  	{
  		WLog_ERR(TAG, "Stream_New failed!");
  		return FALSE;
  	}
  
  	/* TSCredentials (SEQUENCE) */
  	ret = ber_read_sequence_tag(s, &length) &&
  	      /* [0] credType (INTEGER) */
  	      ber_read_contextual_tag(s, 0, &length, TRUE) &&
  	      ber_read_integer(s, NULL) &&
  	      /* [1] credentials (OCTET STRING) */
  	      ber_read_contextual_tag(s, 1, &length, TRUE) &&
  	      ber_read_octet_string_tag(s, &ts_password_creds_length) &&
  	      nla_read_ts_password_creds(nla, s);
  	Stream_Free(s, FALSE);
  	return ret;
  }
  
  static size_t nla_write_ts_credentials(rdpNla* nla, wStream* s)
  {
  	size_t size = 0;
  	size_t passwordSize;
  	size_t innerSize = nla_sizeof_ts_credentials(nla);
  	/* TSCredentials (SEQUENCE) */
  	size += ber_write_sequence_tag(s, innerSize);
  	/* [0] credType (INTEGER) */
  	size += ber_write_contextual_tag(s, 0, ber_sizeof_integer(1), TRUE);
  	size += ber_write_integer(s, 1);
  	/* [1] credentials (OCTET STRING) */
  	passwordSize = ber_sizeof_sequence(nla_sizeof_ts_password_creds(nla));
  	size += ber_write_contextual_tag(s, 1, ber_sizeof_octet_string(passwordSize), TRUE);
  	size += ber_write_octet_string_tag(s, passwordSize);
  	size += nla_write_ts_password_creds(nla, s);
  	return size;
  }
  
  /**
   * Encode TSCredentials structure.
   * @param credssp
   */
  
  static BOOL nla_encode_ts_credentials(rdpNla* nla)
  {
  	wStream* s;
  	size_t length;
  	int DomainLength = 0;
  	int UserLength = 0;
  	int PasswordLength = 0;
  
  	if (nla->identity)
  	{
  		/* TSPasswordCreds */
  		DomainLength = nla->identity->DomainLength;
  		UserLength = nla->identity->UserLength;
  		PasswordLength = nla->identity->PasswordLength;
  	}
  
  	if (nla->settings->DisableCredentialsDelegation && nla->identity)
  	{
  		/* TSPasswordCreds */
  		nla->identity->DomainLength = 0;
  		nla->identity->UserLength = 0;
  		nla->identity->PasswordLength = 0;
  	}
  
  	length = ber_sizeof_sequence(nla_sizeof_ts_credentials(nla));
  
  	if (!sspi_SecBufferAlloc(&nla->tsCredentials, length))
  	{
  		WLog_ERR(TAG, "sspi_SecBufferAlloc failed!");
  		return FALSE;
  	}
  
  	s = Stream_New((BYTE*) nla->tsCredentials.pvBuffer, length);
  
  	if (!s)
  	{
  		sspi_SecBufferFree(&nla->tsCredentials);
  		WLog_ERR(TAG, "Stream_New failed!");
  		return FALSE;
  	}
  
  	nla_write_ts_credentials(nla, s);
  
  	if (nla->settings->DisableCredentialsDelegation && nla->identity)
  	{
  		/* TSPasswordCreds */
  		nla->identity->DomainLength = DomainLength;
  		nla->identity->UserLength = UserLength;
  		nla->identity->PasswordLength = PasswordLength;
  	}
  
  	Stream_Free(s, FALSE);
  	return TRUE;
  }
  
  static SECURITY_STATUS nla_encrypt_ts_credentials(rdpNla* nla)
  {
  	SecBuffer Buffers[2] = { { 0 } };
  	SecBufferDesc Message;
  	SECURITY_STATUS status;
  	const BOOL krb = (_tcsncmp(nla->packageName, KERBEROS_SSP_NAME, ARRAYSIZE(KERBEROS_SSP_NAME)) == 0);
  	const BOOL nego = (_tcsncmp(nla->packageName, NEGO_SSP_NAME, ARRAYSIZE(NEGO_SSP_NAME)) == 0);
  	const BOOL ntlm = (_tcsncmp(nla->packageName,  NTLM_SSP_NAME, ARRAYSIZE(NTLM_SSP_NAME)) == 0);
  
  	if (!nla_encode_ts_credentials(nla))
  		return SEC_E_INSUFFICIENT_MEMORY;
  
  	if (!sspi_SecBufferAlloc(&nla->authInfo,
  	                         nla->tsCredentials.cbBuffer + nla->ContextSizes.cbSecurityTrailer))
  		return SEC_E_INSUFFICIENT_MEMORY;
  
  	if (krb)
  	{
  		Buffers[0].BufferType = SECBUFFER_DATA; /* TSCredentials */
  		Buffers[0].cbBuffer = nla->tsCredentials.cbBuffer;
  		Buffers[0].pvBuffer = nla->authInfo.pvBuffer;
  		CopyMemory(Buffers[0].pvBuffer, nla->tsCredentials.pvBuffer, Buffers[0].cbBuffer);
  		Message.cBuffers = 1;
  		Message.ulVersion = SECBUFFER_VERSION;
  		Message.pBuffers = (PSecBuffer) &Buffers;
  	}
  	else if (ntlm || nego)
  	{
  		Buffers[0].BufferType = SECBUFFER_TOKEN; /* Signature */
  		Buffers[0].cbBuffer = nla->ContextSizes.cbSecurityTrailer;
  		Buffers[0].pvBuffer = nla->authInfo.pvBuffer;
  		MoveMemory(Buffers[0].pvBuffer, nla->authInfo.pvBuffer, Buffers[0].cbBuffer);
  		Buffers[1].BufferType = SECBUFFER_DATA; /* TSCredentials */
  		Buffers[1].cbBuffer = nla->tsCredentials.cbBuffer;
  		Buffers[1].pvBuffer = &((BYTE*) nla->authInfo.pvBuffer)[Buffers[0].cbBuffer];
  		CopyMemory(Buffers[1].pvBuffer, nla->tsCredentials.pvBuffer, Buffers[1].cbBuffer);
  		Message.cBuffers = 2;
  		Message.ulVersion = SECBUFFER_VERSION;
  		Message.pBuffers = (PSecBuffer) &Buffers;
  	}
  
  	status = nla->table->EncryptMessage(&nla->context, 0, &Message, nla->sendSeqNum++);
  
  	if (status != SEC_E_OK)
  	{
  		WLog_ERR(TAG, "EncryptMessage failure %s [0x%08"PRIX32"]",
  		         GetSecurityStatusString(status), status);
  		return status;
  	}
  
  	return SEC_E_OK;
  }
  
  static SECURITY_STATUS nla_decrypt_ts_credentials(rdpNla* nla)
  {
  	int length;
  	BYTE* buffer;
  	ULONG pfQOP;
  	SecBuffer Buffers[2] = { { 0 } };
  	SecBufferDesc Message;
  	SECURITY_STATUS status;
  	const BOOL krb = (_tcsncmp(nla->packageName, KERBEROS_SSP_NAME, ARRAYSIZE(KERBEROS_SSP_NAME)) == 0);
  	const BOOL nego = (_tcsncmp(nla->packageName, NEGO_SSP_NAME, ARRAYSIZE(NEGO_SSP_NAME)) == 0);
  	const BOOL ntlm = (_tcsncmp(nla->packageName,  NTLM_SSP_NAME, ARRAYSIZE(NTLM_SSP_NAME)) == 0);
  
  	if (nla->authInfo.cbBuffer < 1)
  	{
  		WLog_ERR(TAG, "nla_decrypt_ts_credentials missing authInfo buffer");
  		return SEC_E_INVALID_TOKEN;
  	}
  
  	length = nla->authInfo.cbBuffer;
  	buffer = (BYTE*) malloc(length);
  
  	if (!buffer)
  		return SEC_E_INSUFFICIENT_MEMORY;
  
  	if (krb)
  	{
  		CopyMemory(buffer, nla->authInfo.pvBuffer, length);
  		Buffers[0].BufferType = SECBUFFER_DATA; /* Wrapped and encrypted TSCredentials */
  		Buffers[0].cbBuffer = length;
  		Buffers[0].pvBuffer = buffer;
  		Message.cBuffers = 1;
  		Message.ulVersion = SECBUFFER_VERSION;
  		Message.pBuffers = (PSecBuffer) &Buffers;
  	}
  	else if (ntlm || nego)
  	{
  		CopyMemory(buffer, nla->authInfo.pvBuffer, length);
  		Buffers[0].BufferType = SECBUFFER_TOKEN; /* Signature */
  		Buffers[0].cbBuffer = nla->ContextSizes.cbSecurityTrailer;
  		Buffers[0].pvBuffer = buffer;
  		Buffers[1].BufferType = SECBUFFER_DATA; /* TSCredentials */
  		Buffers[1].cbBuffer = length - nla->ContextSizes.cbSecurityTrailer;
  		Buffers[1].pvBuffer = &buffer[ Buffers[0].cbBuffer ];
  		Message.cBuffers = 2;
  		Message.ulVersion = SECBUFFER_VERSION;
  		Message.pBuffers = (PSecBuffer) &Buffers;
  	}
  
  	status = nla->table->DecryptMessage(&nla->context, &Message, nla->recvSeqNum++, &pfQOP);
  
  	if (status != SEC_E_OK)
  	{
  		WLog_ERR(TAG, "DecryptMessage failure %s [0x%08"PRIX32"]",
  		         GetSecurityStatusString(status), status);
  		free(buffer);
  		return status;
  	}
  
  	if (!nla_read_ts_credentials(nla, &Buffers[1]))
  	{
  		free(buffer);
  		return SEC_E_INSUFFICIENT_MEMORY;
  	}
  
  	free(buffer);
  	return SEC_E_OK;
  }
  
  static size_t nla_sizeof_nego_token(size_t length)
  {
  	length = ber_sizeof_octet_string(length);
  	length += ber_sizeof_contextual_tag(length);
  	return length;
  }
  
  static size_t nla_sizeof_nego_tokens(size_t length)
  {
  	length = nla_sizeof_nego_token(length);
  	length += ber_sizeof_sequence_tag(length);
  	length += ber_sizeof_sequence_tag(length);
  	length += ber_sizeof_contextual_tag(length);
  	return length;
  }
  
  static size_t nla_sizeof_pub_key_auth(size_t length)
  {
  	length = ber_sizeof_octet_string(length);
  	length += ber_sizeof_contextual_tag(length);
  	return length;
  }
  
  static size_t nla_sizeof_auth_info(size_t length)
  {
  	length = ber_sizeof_octet_string(length);
  	length += ber_sizeof_contextual_tag(length);
  	return length;
  }
  
  static size_t nla_sizeof_client_nonce(size_t length)
  {
  	length = ber_sizeof_octet_string(length);
  	length += ber_sizeof_contextual_tag(length);
  	return length;
  }
  
  static size_t nla_sizeof_ts_request(size_t length)
  {
  	length += ber_sizeof_integer(2);
  	length += ber_sizeof_contextual_tag(3);
  	return length;
  }
  
  /**
   * Send CredSSP message.
   * @param credssp
   */
  
  BOOL nla_send(rdpNla* nla)
  {
  	wStream* s;
  	size_t length;
  	size_t ts_request_length;
  	size_t nego_tokens_length = 0;
  	size_t pub_key_auth_length = 0;
  	size_t auth_info_length = 0;
  	size_t error_code_context_length = 0;
  	size_t error_code_length = 0;
  	size_t client_nonce_length = 0;
  	nego_tokens_length = (nla->negoToken.cbBuffer > 0) ? nla_sizeof_nego_tokens(
  	                         nla->negoToken.cbBuffer) : 0;
  	pub_key_auth_length = (nla->pubKeyAuth.cbBuffer > 0) ? nla_sizeof_pub_key_auth(
  	                          nla->pubKeyAuth.cbBuffer) : 0;
  	auth_info_length = (nla->authInfo.cbBuffer > 0) ? nla_sizeof_auth_info(nla->authInfo.cbBuffer) : 0;
  	client_nonce_length = (nla->ClientNonce.cbBuffer > 0) ? nla_sizeof_client_nonce(
  	                          nla->ClientNonce.cbBuffer) : 0;
  
  	if (nla->peerVersion >= 3 && nla->peerVersion != 5 && nla->errorCode != 0)
  	{
  		error_code_length = ber_sizeof_integer(nla->errorCode);
  		error_code_context_length = ber_sizeof_contextual_tag(error_code_length);
  	}
  
  	length = nego_tokens_length + pub_key_auth_length + auth_info_length + error_code_context_length +
  	         error_code_length + client_nonce_length;
  	ts_request_length = nla_sizeof_ts_request(length);
  	s = Stream_New(NULL, ber_sizeof_sequence(ts_request_length));
  
  	if (!s)
  	{
  		WLog_ERR(TAG, "Stream_New failed!");
  		return FALSE;
  	}
  
  	/* TSRequest */
  	ber_write_sequence_tag(s, ts_request_length); /* SEQUENCE */
  	/* [0] version */
  	ber_write_contextual_tag(s, 0, 3, TRUE);
  	ber_write_integer(s, nla->version); /* INTEGER */
  
  	/* [1] negoTokens (NegoData) */
  	if (nego_tokens_length > 0)
  	{
  		length = ber_write_contextual_tag(s, 1,
  		                                  ber_sizeof_sequence(ber_sizeof_sequence(ber_sizeof_sequence_octet_string(nla->negoToken.cbBuffer))),
  		                                  TRUE); /* NegoData */
  		length += ber_write_sequence_tag(s,
  		                                 ber_sizeof_sequence(ber_sizeof_sequence_octet_string(
  		                                         nla->negoToken.cbBuffer))); /* SEQUENCE OF NegoDataItem */
  		length += ber_write_sequence_tag(s,
  		                                 ber_sizeof_sequence_octet_string(nla->negoToken.cbBuffer)); /* NegoDataItem */
  		length += ber_write_sequence_octet_string(s, 0, (BYTE*) nla->negoToken.pvBuffer,
  		          nla->negoToken.cbBuffer);  /* OCTET STRING */
  
  		if (length != nego_tokens_length)
  			return FALSE;
  	}
  
  	/* [2] authInfo (OCTET STRING) */
  	if (auth_info_length > 0)
  	{
  		if (ber_write_sequence_octet_string(s, 2, nla->authInfo.pvBuffer,
  		                                    nla->authInfo.cbBuffer) != auth_info_length)
  			return FALSE;
  	}
  
  	/* [3] pubKeyAuth (OCTET STRING) */
  	if (pub_key_auth_length > 0)
  	{
  		if (ber_write_sequence_octet_string(s, 3, nla->pubKeyAuth.pvBuffer,
  		                                    nla->pubKeyAuth.cbBuffer) != pub_key_auth_length)
  			return FALSE;
  	}
  
  	/* [4] errorCode (INTEGER) */
  	if (error_code_length > 0)
  	{
  		ber_write_contextual_tag(s, 4, error_code_length, TRUE);
  		ber_write_integer(s, nla->errorCode);
  	}
  
  	/* [5] clientNonce (OCTET STRING) */
  	if (client_nonce_length > 0)
  	{
  		if (ber_write_sequence_octet_string(s, 5, nla->ClientNonce.pvBuffer,
  		                                    nla->ClientNonce.cbBuffer) != client_nonce_length)
  			return FALSE;
  	}
  
  	Stream_SealLength(s);
  	transport_write(nla->transport, s);
  	Stream_Free(s, TRUE);
  	return TRUE;
  }
  
  static int nla_decode_ts_request(rdpNla* nla, wStream* s)
  {
  	size_t length;
  	UINT32 version = 0;
  
  	/* TSRequest */
  	if (!ber_read_sequence_tag(s, &length) ||
  	    !ber_read_contextual_tag(s, 0, &length, TRUE) ||
  	    !ber_read_integer(s, &version))
  	{
  		return -1;
  	}
  
  	if (nla->peerVersion == 0)
  	{
  		WLog_DBG(TAG, "CredSSP protocol support %"PRIu32", peer supports %"PRIu32,
  				 nla->version, version);
  		nla->peerVersion = version;
  	}
  
  	/* if the peer suddenly changed its version - kick it */
  	if (nla->peerVersion != version)
  	{
  		WLog_ERR(TAG, "CredSSP peer changed protocol version from %"PRIu32" to %"PRIu32,
  				 nla->peerVersion, version);
  		return -1;
  	}
  
  	/* [1] negoTokens (NegoData) */
  	if (ber_read_contextual_tag(s, 1, &length, TRUE) != FALSE)
  	{
  		if (!ber_read_sequence_tag(s, &length) || /* SEQUENCE OF NegoDataItem */
  		    !ber_read_sequence_tag(s, &length) || /* NegoDataItem */
  		    !ber_read_contextual_tag(s, 0, &length, TRUE) || /* [0] negoToken */
  		    !ber_read_octet_string_tag(s, &length) || /* OCTET STRING */
  		    Stream_GetRemainingLength(s) < length)
  		{
  			return -1;
  		}
  
  		if (!sspi_SecBufferAlloc(&nla->negoToken, length))
  			return -1;
  
  		Stream_Read(s, nla->negoToken.pvBuffer, length);
  		nla->negoToken.cbBuffer = length;
  	}
  
  	/* [2] authInfo (OCTET STRING) */
  	if (ber_read_contextual_tag(s, 2, &length, TRUE) != FALSE)
  	{
  		if (!ber_read_octet_string_tag(s, &length) || /* OCTET STRING */
  		    Stream_GetRemainingLength(s) < length)
  			return -1;
  
  		if (!sspi_SecBufferAlloc(&nla->authInfo, length))
  			return -1;
  
  		Stream_Read(s, nla->authInfo.pvBuffer, length);
  		nla->authInfo.cbBuffer = length;
  	}
  
  	/* [3] pubKeyAuth (OCTET STRING) */
  	if (ber_read_contextual_tag(s, 3, &length, TRUE) != FALSE)
  	{
  		if (!ber_read_octet_string_tag(s, &length) || /* OCTET STRING */
  		    Stream_GetRemainingLength(s) < length)
  			return -1;
  
  		if (!sspi_SecBufferAlloc(&nla->pubKeyAuth, length))
  			return -1;
  
  		Stream_Read(s, nla->pubKeyAuth.pvBuffer, length);
  		nla->pubKeyAuth.cbBuffer = length;
  	}
  
  	/* [4] errorCode (INTEGER) */
  	if (nla->peerVersion >= 3)
  	{
  		if (ber_read_contextual_tag(s, 4, &length, TRUE) != FALSE)
  		{
  			if (!ber_read_integer(s, &nla->errorCode))
  				return -1;
  		}
  
  		if (nla->peerVersion >= 5)
  		{
  			if (ber_read_contextual_tag(s, 5, &length, TRUE) != FALSE)
  			{
  				if (!ber_read_octet_string_tag(s, &length) || /* OCTET STRING */
  				    Stream_GetRemainingLength(s) < length)
  					return -1;
  
  				if (!sspi_SecBufferAlloc(&nla->ClientNonce, length))
  					return -1;
  
  				Stream_Read(s, nla->ClientNonce.pvBuffer, length);
  				nla->ClientNonce.cbBuffer = length;
  			}
  		}
  	}
  
  	return 1;
  }
  
  int nla_recv_pdu(rdpNla* nla, wStream* s)
  {
  	if (nla_decode_ts_request(nla, s) < 1)
  		return -1;
  
  	if (nla->errorCode)
  	{
  		UINT32 code;
  
  		switch (nla->errorCode)
  		{
  			case STATUS_PASSWORD_MUST_CHANGE:
  				code = FREERDP_ERROR_CONNECT_PASSWORD_MUST_CHANGE;
  				break;
  
  			case STATUS_PASSWORD_EXPIRED:
  				code = FREERDP_ERROR_CONNECT_PASSWORD_EXPIRED;
  				break;
  
  			case STATUS_ACCOUNT_DISABLED:
  				code = FREERDP_ERROR_CONNECT_ACCOUNT_DISABLED;
  				break;
  
  			case STATUS_LOGON_FAILURE:
  				code = FREERDP_ERROR_CONNECT_LOGON_FAILURE;
  				break;
  
  			case STATUS_WRONG_PASSWORD:
  				code = FREERDP_ERROR_CONNECT_WRONG_PASSWORD;
  				break;
  
  			case STATUS_ACCESS_DENIED:
  				code = FREERDP_ERROR_CONNECT_ACCESS_DENIED;
  				break;
  
  			case STATUS_ACCOUNT_RESTRICTION:
  				code = FREERDP_ERROR_CONNECT_ACCOUNT_RESTRICTION;
  				break;
  
  			case STATUS_ACCOUNT_LOCKED_OUT:
  				code = FREERDP_ERROR_CONNECT_ACCOUNT_LOCKED_OUT;
  				break;
  
  			case STATUS_ACCOUNT_EXPIRED:
  				code = FREERDP_ERROR_CONNECT_ACCOUNT_EXPIRED;
  				break;
  
  			case STATUS_LOGON_TYPE_NOT_GRANTED:
  				code = FREERDP_ERROR_CONNECT_LOGON_TYPE_NOT_GRANTED;
  				break;
  
  			default:
  				WLog_ERR(TAG, "SPNEGO failed with NTSTATUS: 0x%08"PRIX32"", nla->errorCode);
  				code = FREERDP_ERROR_AUTHENTICATION_FAILED;
  				break;
  		}
  
  		freerdp_set_last_error(nla->instance->context, code);
  		return -1;
  	}
  
  	if (nla_client_recv(nla) < 1)
  		return -1;
  
  	return 1;
  }
  
  int nla_recv(rdpNla* nla)
  {
  	wStream* s;
  	int status;
  	s = Stream_New(NULL, 4096);
  
  	if (!s)
  	{
  		WLog_ERR(TAG, "Stream_New failed!");
  		return -1;
  	}
  
  	status = transport_read_pdu(nla->transport, s);
  
  	if (status < 0)
  	{
  		WLog_ERR(TAG, "nla_recv() error: %d", status);
  		Stream_Free(s, TRUE);
  		return -1;
  	}
  
  	if (nla_decode_ts_request(nla, s) < 1)
  	{
  		Stream_Free(s, TRUE);
  		return -1;
  	}
  
  	Stream_Free(s, TRUE);
  	return 1;
  }
  
  void nla_buffer_print(rdpNla* nla)
  {
  	if (nla->negoToken.cbBuffer > 0)
  	{
  		WLog_DBG(TAG, "NLA.negoToken (length = %"PRIu32"):", nla->negoToken.cbBuffer);
  		winpr_HexDump(TAG, WLOG_DEBUG, nla->negoToken.pvBuffer, nla->negoToken.cbBuffer);
  	}
  
  	if (nla->pubKeyAuth.cbBuffer > 0)
  	{
  		WLog_DBG(TAG, "NLA.pubKeyAuth (length = %"PRIu32"):", nla->pubKeyAuth.cbBuffer);
  		winpr_HexDump(TAG, WLOG_DEBUG, nla->pubKeyAuth.pvBuffer, nla->pubKeyAuth.cbBuffer);
  	}
  
  	if (nla->authInfo.cbBuffer > 0)
  	{
  		WLog_DBG(TAG, "NLA.authInfo (length = %"PRIu32"):", nla->authInfo.cbBuffer);
  		winpr_HexDump(TAG, WLOG_DEBUG, nla->authInfo.pvBuffer, nla->authInfo.cbBuffer);
  	}
  }
  
  void nla_buffer_free(rdpNla* nla)
  {
  	sspi_SecBufferFree(&nla->negoToken);
  	sspi_SecBufferFree(&nla->pubKeyAuth);
  	sspi_SecBufferFree(&nla->authInfo);
  }
  
  LPTSTR nla_make_spn(const char* ServiceClass, const char* hostname)
  {
  	DWORD status;
  	DWORD SpnLength;
  	LPTSTR hostnameX = NULL;
  	LPTSTR ServiceClassX = NULL;
  	LPTSTR ServicePrincipalName = NULL;
  #ifdef UNICODE
  	ConvertToUnicode(CP_UTF8, 0, hostname, -1, &hostnameX, 0);
  	ConvertToUnicode(CP_UTF8, 0, ServiceClass, -1, &ServiceClassX, 0);
  #else
  	hostnameX = _strdup(hostname);
  	ServiceClassX = _strdup(ServiceClass);
  #endif
  
  	if (!hostnameX || !ServiceClassX)
  	{
  		free(hostnameX);
  		free(ServiceClassX);
  		return NULL;
  	}
  
  	if (!ServiceClass)
  	{
  		ServicePrincipalName = (LPTSTR) _tcsdup(hostnameX);
  		free(ServiceClassX);
  		free(hostnameX);
  		return ServicePrincipalName;
  	}
  
  	SpnLength = 0;
  	status = DsMakeSpn(ServiceClassX, hostnameX, NULL, 0, NULL, &SpnLength, NULL);
  
  	if (status != ERROR_BUFFER_OVERFLOW)
  	{
  		free(ServiceClassX);
  		free(hostnameX);
  		return NULL;
  	}
  
  	ServicePrincipalName = (LPTSTR) calloc(SpnLength, sizeof(TCHAR));
  
  	if (!ServicePrincipalName)
  	{
  		free(ServiceClassX);
  		free(hostnameX);
  		return NULL;
  	}
  
  	status = DsMakeSpn(ServiceClassX, hostnameX, NULL, 0, NULL, &SpnLength, ServicePrincipalName);
  
  	if (status != ERROR_SUCCESS)
  	{
  		free(ServicePrincipalName);
  		free(ServiceClassX);
  		free(hostnameX);
  		return NULL;
  	}
  
  	free(ServiceClassX);
  	free(hostnameX);
  	return ServicePrincipalName;
  }
  
  /**
   * Create new CredSSP state machine.
   * @param transport
   * @return new CredSSP state machine.
   */
  
  rdpNla* nla_new(freerdp* instance, rdpTransport* transport, rdpSettings* settings)
  {
  	rdpNla* nla = (rdpNla*) calloc(1, sizeof(rdpNla));
  
  	if (!nla)
  		return NULL;
  
  	nla->identity = calloc(1, sizeof(SEC_WINNT_AUTH_IDENTITY));
  
  	if (!nla->identity)
  	{
  		free(nla);
  		return NULL;
  	}
  
  	nla->instance = instance;
  	nla->settings = settings;
  	nla->server = settings->ServerMode;
  	nla->transport = transport;
  	nla->sendSeqNum = 0;
  	nla->recvSeqNum = 0;
  	nla->version = 6;
  
  	ZeroMemory(&nla->ClientNonce, sizeof(SecBuffer));
  	ZeroMemory(&nla->negoToken, sizeof(SecBuffer));
  	ZeroMemory(&nla->pubKeyAuth, sizeof(SecBuffer));
  	ZeroMemory(&nla->authInfo, sizeof(SecBuffer));
  	SecInvalidateHandle(&nla->context);
  
  	if (settings->NtlmSamFile)
  	{
  		nla->SamFile = _strdup(settings->NtlmSamFile);
  
  		if (!nla->SamFile)
  			goto cleanup;
  	}
  
  	/* init to 0 or we end up freeing a bad pointer if the alloc fails */
  	if (!sspi_SecBufferAlloc(&nla->ClientNonce, NonceLength))
  		goto cleanup;
  
  	/* generate random 32-byte nonce */
  	if (winpr_RAND(nla->ClientNonce.pvBuffer, NonceLength) < 0)
  		goto cleanup;
  
  	if (nla->server)
  	{
  		LONG status;
  		HKEY hKey;
  		DWORD dwType;
  		DWORD dwSize;
  		status = RegOpenKeyExA(HKEY_LOCAL_MACHINE, SERVER_KEY,
  		                       0, KEY_READ | KEY_WOW64_64KEY, &hKey);
  
  		if (status != ERROR_SUCCESS)
  			return nla;
  
  		status = RegQueryValueEx(hKey, _T("SspiModule"), NULL, &dwType, NULL, &dwSize);
  
  		if (status != ERROR_SUCCESS)
  		{
  			RegCloseKey(hKey);
  			return nla;
  		}
  
  		nla->SspiModule = (LPTSTR) malloc(dwSize + sizeof(TCHAR));
  
  		if (!nla->SspiModule)
  		{
  			RegCloseKey(hKey);
  			goto cleanup;
  		}
  
  		status = RegQueryValueEx(hKey, _T("SspiModule"), NULL, &dwType,
  		                         (BYTE*) nla->SspiModule, &dwSize);
  
  		if (status == ERROR_SUCCESS)
  			WLog_INFO(TAG, "Using SSPI Module: %s", nla->SspiModule);
  
  		RegCloseKey(hKey);
  	}
  
  	return nla;
  
  cleanup:
  	nla_free(nla);
  	return NULL;
  }
  
  /**
   * Free CredSSP state machine.
   * @param credssp
   */
  
  void nla_free(rdpNla* nla)
  {
  	if (!nla)
  		return;
  
  	if (nla->table)
  	{
  		SECURITY_STATUS status;
  
  		if (SecIsValidHandle(&nla->credentials))
  		{
  			status = nla->table->FreeCredentialsHandle(&nla->credentials);
  
  			if (status != SEC_E_OK)
  			{
  				WLog_WARN(TAG, "FreeCredentialsHandle status %s [0x%08"PRIX32"]",
  				          GetSecurityStatusString(status), status);
  			}
  
  			SecInvalidateHandle(&nla->credentials);
  		}
  
  		status = nla->table->DeleteSecurityContext(&nla->context);
  
  		if (status != SEC_E_OK)
  		{
  			WLog_WARN(TAG, "DeleteSecurityContext status %s [0x%08"PRIX32"]",
  			          GetSecurityStatusString(status), status);
  		}
  	}
  
  	free(nla->SamFile);
  	nla->SamFile = NULL;
  	sspi_SecBufferFree(&nla->ClientNonce);
  	sspi_SecBufferFree(&nla->PublicKey);
  	sspi_SecBufferFree(&nla->tsCredentials);
  	free(nla->ServicePrincipalName);
  	nla_identity_free(nla->identity);
  	free(nla);
  }
  