/**
 * WinPR: Windows Portable Runtime
 * Schannel Security Package
 *
 * Copyright 2012-2014 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 <winpr/config.h>

#include <winpr/crt.h>
#include <winpr/sspi.h>

#include "schannel.h"

#include "../sspi.h"
#include "../../log.h"

static char* SCHANNEL_PACKAGE_NAME = "Schannel";

#define TAG WINPR_TAG("sspi.Schannel")

SCHANNEL_CONTEXT* schannel_ContextNew(void)
{
	SCHANNEL_CONTEXT* context = nullptr;
	context = (SCHANNEL_CONTEXT*)calloc(1, sizeof(SCHANNEL_CONTEXT));

	if (!context)
		return nullptr;

	context->openssl = schannel_openssl_new();

	if (!context->openssl)
	{
		free(context);
		return nullptr;
	}

	return context;
}

void schannel_ContextFree(SCHANNEL_CONTEXT* context)
{
	if (!context)
		return;

	schannel_openssl_free(context->openssl);
	free(context);
}

static SCHANNEL_CREDENTIALS* schannel_CredentialsNew(void)
{
	SCHANNEL_CREDENTIALS* credentials = nullptr;
	credentials = (SCHANNEL_CREDENTIALS*)calloc(1, sizeof(SCHANNEL_CREDENTIALS));
	return credentials;
}

static void schannel_CredentialsFree(SCHANNEL_CREDENTIALS* credentials)
{
	free(credentials);
}

static ALG_ID schannel_SupportedAlgs[] = { CALG_AES_128,
	                                       CALG_AES_256,
	                                       CALG_RC4,
	                                       CALG_DES,
	                                       CALG_3DES,
	                                       CALG_MD5,
	                                       CALG_SHA1,
	                                       CALG_SHA_256,
	                                       CALG_SHA_384,
	                                       CALG_SHA_512,
	                                       CALG_RSA_SIGN,
	                                       CALG_DH_EPHEM,
	                                       (ALG_CLASS_KEY_EXCHANGE | ALG_TYPE_RESERVED7 |
	                                        6), /* what is this? */
	                                       CALG_DSS_SIGN,
	                                       CALG_ECDSA };

static SECURITY_STATUS SEC_ENTRY schannel_QueryCredentialsAttributesW(
    WINPR_ATTR_UNUSED PCredHandle phCredential, ULONG ulAttribute, void* pBuffer)
{
	if (ulAttribute == SECPKG_ATTR_SUPPORTED_ALGS)
	{
		PSecPkgCred_SupportedAlgs SupportedAlgs = (PSecPkgCred_SupportedAlgs)pBuffer;
		SupportedAlgs->cSupportedAlgs = sizeof(schannel_SupportedAlgs) / sizeof(ALG_ID);
		SupportedAlgs->palgSupportedAlgs = (ALG_ID*)schannel_SupportedAlgs;
		return SEC_E_OK;
	}
	else if (ulAttribute == SECPKG_ATTR_CIPHER_STRENGTHS)
	{
		PSecPkgCred_CipherStrengths CipherStrengths = (PSecPkgCred_CipherStrengths)pBuffer;
		CipherStrengths->dwMinimumCipherStrength = 40;
		CipherStrengths->dwMaximumCipherStrength = 256;
		return SEC_E_OK;
	}
	else if (ulAttribute == SECPKG_ATTR_SUPPORTED_PROTOCOLS)
	{
		PSecPkgCred_SupportedProtocols SupportedProtocols = (PSecPkgCred_SupportedProtocols)pBuffer;
		/* Observed SupportedProtocols: 0x208A0 */
		SupportedProtocols->grbitProtocol = (SP_PROT_CLIENTS | SP_PROT_SERVERS);
		return SEC_E_OK;
	}

	WLog_ERR(TAG, "TODO: Implement ulAttribute=%08" PRIx32, ulAttribute);
	return SEC_E_UNSUPPORTED_FUNCTION;
}

static SECURITY_STATUS SEC_ENTRY schannel_QueryCredentialsAttributesA(PCredHandle phCredential,
                                                                      ULONG ulAttribute,
                                                                      void* pBuffer)
{
	return schannel_QueryCredentialsAttributesW(phCredential, ulAttribute, pBuffer);
}

static SECURITY_STATUS SEC_ENTRY schannel_AcquireCredentialsHandleW(
    WINPR_ATTR_UNUSED SEC_WCHAR* pszPrincipal, WINPR_ATTR_UNUSED SEC_WCHAR* pszPackage,
    ULONG fCredentialUse, WINPR_ATTR_UNUSED void* pvLogonID, void* pAuthData,
    WINPR_ATTR_UNUSED SEC_GET_KEY_FN pGetKeyFn, WINPR_ATTR_UNUSED void* pvGetKeyArgument,
    PCredHandle phCredential, WINPR_ATTR_UNUSED PTimeStamp ptsExpiry)
{
	SCHANNEL_CREDENTIALS* credentials = nullptr;

	if (fCredentialUse == SECPKG_CRED_OUTBOUND)
	{
		SCHANNEL_CRED* cred = nullptr;
		credentials = schannel_CredentialsNew();
		credentials->fCredentialUse = fCredentialUse;
		cred = (SCHANNEL_CRED*)pAuthData;

		if (cred)
		{
			CopyMemory(&credentials->cred, cred, sizeof(SCHANNEL_CRED));
		}

		sspi_SecureHandleSetLowerPointer(phCredential, (void*)credentials);
		sspi_SecureHandleSetUpperPointer(phCredential, (void*)SCHANNEL_PACKAGE_NAME);
		return SEC_E_OK;
	}
	else if (fCredentialUse == SECPKG_CRED_INBOUND)
	{
		credentials = schannel_CredentialsNew();
		credentials->fCredentialUse = fCredentialUse;
		sspi_SecureHandleSetLowerPointer(phCredential, (void*)credentials);
		sspi_SecureHandleSetUpperPointer(phCredential, (void*)SCHANNEL_PACKAGE_NAME);
		return SEC_E_OK;
	}

	return SEC_E_OK;
}

static SECURITY_STATUS SEC_ENTRY schannel_AcquireCredentialsHandleA(
    SEC_CHAR* pszPrincipal, SEC_CHAR* pszPackage, ULONG fCredentialUse, void* pvLogonID,
    void* pAuthData, SEC_GET_KEY_FN pGetKeyFn, void* pvGetKeyArgument, PCredHandle phCredential,
    PTimeStamp ptsExpiry)
{
	SECURITY_STATUS status = 0;
	SEC_WCHAR* pszPrincipalW = nullptr;
	SEC_WCHAR* pszPackageW = nullptr;
	if (pszPrincipal)
		pszPrincipalW = ConvertUtf8ToWCharAlloc(pszPrincipal, nullptr);
	if (pszPackage)
		pszPackageW = ConvertUtf8ToWCharAlloc(pszPackage, nullptr);

	status = schannel_AcquireCredentialsHandleW(pszPrincipalW, pszPackageW, fCredentialUse,
	                                            pvLogonID, pAuthData, pGetKeyFn, pvGetKeyArgument,
	                                            phCredential, ptsExpiry);
	free(pszPrincipalW);
	free(pszPackageW);
	return status;
}

static SECURITY_STATUS SEC_ENTRY schannel_FreeCredentialsHandle(PCredHandle phCredential)
{
	if (!phCredential)
		return SEC_E_INVALID_HANDLE;

	SCHANNEL_CREDENTIALS* credentials =
	    (SCHANNEL_CREDENTIALS*)sspi_SecureHandleGetLowerPointer(phCredential);
	sspi_SecureHandleInvalidate(phCredential);
	if (!credentials)
		return SEC_E_INVALID_HANDLE;

	schannel_CredentialsFree(credentials);
	return SEC_E_OK;
}

static SECURITY_STATUS SEC_ENTRY schannel_InitializeSecurityContextW(
    PCredHandle phCredential, PCtxtHandle phContext, WINPR_ATTR_UNUSED SEC_WCHAR* pszTargetName,
    WINPR_ATTR_UNUSED ULONG fContextReq, WINPR_ATTR_UNUSED ULONG Reserved1,
    WINPR_ATTR_UNUSED ULONG TargetDataRep, PSecBufferDesc pInput, WINPR_ATTR_UNUSED ULONG Reserved2,
    PCtxtHandle phNewContext, PSecBufferDesc pOutput, WINPR_ATTR_UNUSED PULONG pfContextAttr,
    WINPR_ATTR_UNUSED PTimeStamp ptsExpiry)
{
	SECURITY_STATUS status = 0;
	SCHANNEL_CONTEXT* context = nullptr;
	SCHANNEL_CREDENTIALS* credentials = nullptr;

	/* behave like windows SSPIs that don't want empty context */
	if (phContext && !phContext->dwLower && !phContext->dwUpper)
		return SEC_E_INVALID_HANDLE;

	context = sspi_SecureHandleGetLowerPointer(phContext);

	if (!context)
	{
		context = schannel_ContextNew();

		if (!context)
			return SEC_E_INSUFFICIENT_MEMORY;

		credentials = (SCHANNEL_CREDENTIALS*)sspi_SecureHandleGetLowerPointer(phCredential);
		context->server = FALSE;
		CopyMemory(&context->cred, &credentials->cred, sizeof(SCHANNEL_CRED));
		sspi_SecureHandleSetLowerPointer(phNewContext, context);
		sspi_SecureHandleSetUpperPointer(phNewContext, (void*)SCHANNEL_PACKAGE_NAME);
		schannel_openssl_client_init(context->openssl);
	}

	status = schannel_openssl_client_process_tokens(context->openssl, pInput, pOutput);
	return status;
}

static SECURITY_STATUS SEC_ENTRY schannel_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 = 0;
	SEC_WCHAR* pszTargetNameW = nullptr;

	if (pszTargetName != nullptr)
	{
		pszTargetNameW = ConvertUtf8ToWCharAlloc(pszTargetName, nullptr);
		if (!pszTargetNameW)
			return SEC_E_INSUFFICIENT_MEMORY;
	}

	status = schannel_InitializeSecurityContextW(
	    phCredential, phContext, pszTargetNameW, fContextReq, Reserved1, TargetDataRep, pInput,
	    Reserved2, phNewContext, pOutput, pfContextAttr, ptsExpiry);
	free(pszTargetNameW);
	return status;
}

static SECURITY_STATUS SEC_ENTRY schannel_AcceptSecurityContext(
    WINPR_ATTR_UNUSED PCredHandle phCredential, PCtxtHandle phContext, PSecBufferDesc pInput,
    WINPR_ATTR_UNUSED ULONG fContextReq, WINPR_ATTR_UNUSED ULONG TargetDataRep,
    PCtxtHandle phNewContext, PSecBufferDesc pOutput, WINPR_ATTR_UNUSED PULONG pfContextAttr,
    WINPR_ATTR_UNUSED PTimeStamp ptsTimeStamp)
{
	SECURITY_STATUS status = 0;
	SCHANNEL_CONTEXT* context = nullptr;

	/* behave like windows SSPIs that don't want empty context */
	if (phContext && !phContext->dwLower && !phContext->dwUpper)
		return SEC_E_INVALID_HANDLE;

	context = (SCHANNEL_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);

	if (!context)
	{
		context = schannel_ContextNew();

		if (!context)
			return SEC_E_INSUFFICIENT_MEMORY;

		context->server = TRUE;
		sspi_SecureHandleSetLowerPointer(phNewContext, context);
		sspi_SecureHandleSetUpperPointer(phNewContext, (void*)SCHANNEL_PACKAGE_NAME);
		schannel_openssl_server_init(context->openssl);
	}

	status = schannel_openssl_server_process_tokens(context->openssl, pInput, pOutput);
	return status;
}

static SECURITY_STATUS SEC_ENTRY schannel_DeleteSecurityContext(PCtxtHandle phContext)
{
	SCHANNEL_CONTEXT* context = (SCHANNEL_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);
	sspi_SecureHandleInvalidate(phContext);

	if (!context)
		return SEC_E_INVALID_HANDLE;

	schannel_ContextFree(context);
	return SEC_E_OK;
}

static SECURITY_STATUS SEC_ENTRY schannel_QueryContextAttributes(PCtxtHandle phContext,
                                                                 ULONG ulAttribute, void* pBuffer)
{
	if (!phContext)
		return SEC_E_INVALID_HANDLE;

	if (!pBuffer)
		return SEC_E_INSUFFICIENT_MEMORY;

	if (ulAttribute == SECPKG_ATTR_SIZES)
	{
		SecPkgContext_Sizes* Sizes = (SecPkgContext_Sizes*)pBuffer;
		Sizes->cbMaxToken = 0x6000;
		Sizes->cbMaxSignature = 16;
		Sizes->cbBlockSize = 0;
		Sizes->cbSecurityTrailer = 16;
		return SEC_E_OK;
	}
	else if (ulAttribute == SECPKG_ATTR_STREAM_SIZES)
	{
		SecPkgContext_StreamSizes* StreamSizes = (SecPkgContext_StreamSizes*)pBuffer;
		StreamSizes->cbHeader = 5;
		StreamSizes->cbTrailer = 36;
		StreamSizes->cbMaximumMessage = 0x4000;
		StreamSizes->cBuffers = 4;
		StreamSizes->cbBlockSize = 16;
		return SEC_E_OK;
	}

	WLog_ERR(TAG, "TODO: Implement ulAttribute=%08" PRIx32, ulAttribute);
	return SEC_E_UNSUPPORTED_FUNCTION;
}

static SECURITY_STATUS SEC_ENTRY schannel_MakeSignature(WINPR_ATTR_UNUSED PCtxtHandle phContext,
                                                        WINPR_ATTR_UNUSED ULONG fQOP,
                                                        WINPR_ATTR_UNUSED PSecBufferDesc pMessage,
                                                        WINPR_ATTR_UNUSED ULONG MessageSeqNo)
{
	return SEC_E_OK;
}

static SECURITY_STATUS SEC_ENTRY schannel_VerifySignature(WINPR_ATTR_UNUSED PCtxtHandle phContext,
                                                          WINPR_ATTR_UNUSED PSecBufferDesc pMessage,
                                                          WINPR_ATTR_UNUSED ULONG MessageSeqNo,
                                                          WINPR_ATTR_UNUSED ULONG* pfQOP)
{
	return SEC_E_OK;
}

static SECURITY_STATUS SEC_ENTRY schannel_EncryptMessage(WINPR_ATTR_UNUSED PCtxtHandle phContext,
                                                         WINPR_ATTR_UNUSED ULONG fQOP,
                                                         PSecBufferDesc pMessage,
                                                         WINPR_ATTR_UNUSED ULONG MessageSeqNo)
{
	SECURITY_STATUS status = 0;
	SCHANNEL_CONTEXT* context = nullptr;
	context = (SCHANNEL_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);

	if (!context)
		return SEC_E_INVALID_HANDLE;

	status = schannel_openssl_encrypt_message(context->openssl, pMessage);
	return status;
}

static SECURITY_STATUS SEC_ENTRY schannel_DecryptMessage(PCtxtHandle phContext,
                                                         PSecBufferDesc pMessage,
                                                         WINPR_ATTR_UNUSED ULONG MessageSeqNo,
                                                         WINPR_ATTR_UNUSED ULONG* pfQOP)
{
	SECURITY_STATUS status = 0;
	SCHANNEL_CONTEXT* context = nullptr;
	context = (SCHANNEL_CONTEXT*)sspi_SecureHandleGetLowerPointer(phContext);

	if (!context)
		return SEC_E_INVALID_HANDLE;

	status = schannel_openssl_decrypt_message(context->openssl, pMessage);
	return status;
}

const SecurityFunctionTableA SCHANNEL_SecurityFunctionTableA = {
	3,                                    /* dwVersion */
	nullptr,                              /* EnumerateSecurityPackages */
	schannel_QueryCredentialsAttributesA, /* QueryCredentialsAttributes */
	schannel_AcquireCredentialsHandleA,   /* AcquireCredentialsHandle */
	schannel_FreeCredentialsHandle,       /* FreeCredentialsHandle */
	nullptr,                              /* Reserved2 */
	schannel_InitializeSecurityContextA,  /* InitializeSecurityContext */
	schannel_AcceptSecurityContext,       /* AcceptSecurityContext */
	nullptr,                              /* CompleteAuthToken */
	schannel_DeleteSecurityContext,       /* DeleteSecurityContext */
	nullptr,                              /* ApplyControlToken */
	schannel_QueryContextAttributes,      /* QueryContextAttributes */
	nullptr,                              /* ImpersonateSecurityContext */
	nullptr,                              /* RevertSecurityContext */
	schannel_MakeSignature,               /* MakeSignature */
	schannel_VerifySignature,             /* VerifySignature */
	nullptr,                              /* FreeContextBuffer */
	nullptr,                              /* QuerySecurityPackageInfo */
	nullptr,                              /* Reserved3 */
	nullptr,                              /* Reserved4 */
	nullptr,                              /* ExportSecurityContext */
	nullptr,                              /* ImportSecurityContext */
	nullptr,                              /* AddCredentials */
	nullptr,                              /* Reserved8 */
	nullptr,                              /* QuerySecurityContextToken */
	schannel_EncryptMessage,              /* EncryptMessage */
	schannel_DecryptMessage,              /* DecryptMessage */
	nullptr,                              /* SetContextAttributes */
	nullptr,                              /* SetCredentialsAttributes */
};

const SecurityFunctionTableW SCHANNEL_SecurityFunctionTableW = {
	3,                                    /* dwVersion */
	nullptr,                              /* EnumerateSecurityPackages */
	schannel_QueryCredentialsAttributesW, /* QueryCredentialsAttributes */
	schannel_AcquireCredentialsHandleW,   /* AcquireCredentialsHandle */
	schannel_FreeCredentialsHandle,       /* FreeCredentialsHandle */
	nullptr,                              /* Reserved2 */
	schannel_InitializeSecurityContextW,  /* InitializeSecurityContext */
	schannel_AcceptSecurityContext,       /* AcceptSecurityContext */
	nullptr,                              /* CompleteAuthToken */
	schannel_DeleteSecurityContext,       /* DeleteSecurityContext */
	nullptr,                              /* ApplyControlToken */
	schannel_QueryContextAttributes,      /* QueryContextAttributes */
	nullptr,                              /* ImpersonateSecurityContext */
	nullptr,                              /* RevertSecurityContext */
	schannel_MakeSignature,               /* MakeSignature */
	schannel_VerifySignature,             /* VerifySignature */
	nullptr,                              /* FreeContextBuffer */
	nullptr,                              /* QuerySecurityPackageInfo */
	nullptr,                              /* Reserved3 */
	nullptr,                              /* Reserved4 */
	nullptr,                              /* ExportSecurityContext */
	nullptr,                              /* ImportSecurityContext */
	nullptr,                              /* AddCredentials */
	nullptr,                              /* Reserved8 */
	nullptr,                              /* QuerySecurityContextToken */
	schannel_EncryptMessage,              /* EncryptMessage */
	schannel_DecryptMessage,              /* DecryptMessage */
	nullptr,                              /* SetContextAttributes */
	nullptr,                              /* SetCredentialsAttributes */
};

const SecPkgInfoA SCHANNEL_SecPkgInfoA = {
	0x000107B3,                 /* fCapabilities */
	1,                          /* wVersion */
	0x000E,                     /* wRPCID */
	SCHANNEL_CB_MAX_TOKEN,      /* cbMaxToken */
	"Schannel",                 /* Name */
	"Schannel Security Package" /* Comment */
};

static WCHAR SCHANNEL_SecPkgInfoW_NameBuffer[32] = WINPR_C_ARRAY_INIT;
static WCHAR SCHANNEL_SecPkgInfoW_CommentBuffer[32] = WINPR_C_ARRAY_INIT;

const SecPkgInfoW SCHANNEL_SecPkgInfoW = {
	0x000107B3,                        /* fCapabilities */
	1,                                 /* wVersion */
	0x000E,                            /* wRPCID */
	SCHANNEL_CB_MAX_TOKEN,             /* cbMaxToken */
	SCHANNEL_SecPkgInfoW_NameBuffer,   /* Name */
	SCHANNEL_SecPkgInfoW_CommentBuffer /* Comment */
};

BOOL SCHANNEL_init(void)
{
	InitializeConstWCharFromUtf8(SCHANNEL_SecPkgInfoA.Name, SCHANNEL_SecPkgInfoW_NameBuffer,
	                             ARRAYSIZE(SCHANNEL_SecPkgInfoW_NameBuffer));
	InitializeConstWCharFromUtf8(SCHANNEL_SecPkgInfoA.Comment, SCHANNEL_SecPkgInfoW_CommentBuffer,
	                             ARRAYSIZE(SCHANNEL_SecPkgInfoW_CommentBuffer));
	return TRUE;
}
