FreeRDP/libfreerdp/core/license.c

/**
 * FreeRDP: A Remote Desktop Protocol Implementation
 * RDP Licensing
 *
 * Copyright 2011-2013 Marc-Andre Moreau <marcandre.moreau@gmail.com>
 * Copyright 2014 Norbert Federa <norbert.federa@thincast.com>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <winpr/crt.h>
#include <winpr/crypto.h>
#include <freerdp/log.h>

#include "redirection.h"
#include "certificate.h"

#include "license.h"

#define TAG FREERDP_TAG("core.license")

/* #define LICENSE_NULL_CLIENT_RANDOM		1 */
/* #define LICENSE_NULL_PREMASTER_SECRET		1 */

static wStream* license_send_stream_init(rdpLicense* license);

static void license_generate_randoms(rdpLicense* license);
static BOOL license_generate_keys(rdpLicense* license);
static BOOL license_generate_hwid(rdpLicense* license);
static BOOL license_encrypt_premaster_secret(rdpLicense* license);
static BOOL license_decrypt_platform_challenge(rdpLicense* license);

static LICENSE_PRODUCT_INFO* license_new_product_info(void);
static void license_free_product_info(LICENSE_PRODUCT_INFO* productInfo);
static BOOL license_read_product_info(wStream* s, LICENSE_PRODUCT_INFO* productInfo);

static LICENSE_BLOB* license_new_binary_blob(UINT16 type);
static void license_free_binary_blob(LICENSE_BLOB* blob);
static BOOL license_read_binary_blob(wStream* s, LICENSE_BLOB* blob);
static BOOL license_write_binary_blob(wStream* s, LICENSE_BLOB* blob);

static SCOPE_LIST* license_new_scope_list(void);
static void license_free_scope_list(SCOPE_LIST* scopeList);
static BOOL license_read_scope_list(wStream* s, SCOPE_LIST* scopeList);

static BOOL license_read_license_request_packet(rdpLicense* license, wStream* s);
static BOOL license_read_platform_challenge_packet(rdpLicense* license, wStream* s);
static void license_read_new_license_packet(rdpLicense* license, wStream* s);
static void license_read_upgrade_license_packet(rdpLicense* license, wStream* s);
static BOOL license_read_error_alert_packet(rdpLicense* license, wStream* s);

static BOOL license_write_new_license_request_packet(rdpLicense* license, wStream* s);
static BOOL license_send_new_license_request_packet(rdpLicense* license);

static BOOL license_write_platform_challenge_response_packet(
    rdpLicense* license, wStream* s, BYTE* mac_data);
static BOOL license_send_platform_challenge_response_packet(rdpLicense* license);

#ifdef WITH_DEBUG_LICENSE

static const char* const LICENSE_MESSAGE_STRINGS[] =
{
	"",
	"License Request",
	"Platform Challenge",
	"New License",
	"Upgrade License",
	"", "", "", "", "", "",
	"", "", "", "", "", "",
	"",
	"License Info",
	"New License Request",
	"",
	"Platform Challenge Response",
	"", "", "", "", "", "", "", "", "",
	"Error Alert"
};

static const char* const error_codes[] =
{
	"ERR_UNKNOWN",
	"ERR_INVALID_SERVER_CERTIFICATE",
	"ERR_NO_LICENSE",
	"ERR_INVALID_MAC",
	"ERR_INVALID_SCOPE",
	"ERR_UNKNOWN",
	"ERR_NO_LICENSE_SERVER",
	"STATUS_VALID_CLIENT",
	"ERR_INVALID_CLIENT",
	"ERR_UNKNOWN",
	"ERR_UNKNOWN",
	"ERR_INVALID_PRODUCT_ID",
	"ERR_INVALID_MESSAGE_LENGTH"
};

static const char* const  state_transitions[] =
{
	"ST_UNKNOWN",
	"ST_TOTAL_ABORT",
	"ST_NO_TRANSITION",
	"ST_RESET_PHASE_TO_START",
	"ST_RESEND_LAST_MESSAGE"
};

static void license_print_product_info(LICENSE_PRODUCT_INFO* productInfo)
{
	char* CompanyName = NULL;
	char* ProductId = NULL;
	ConvertFromUnicode(CP_UTF8, 0, (WCHAR*) productInfo->pbCompanyName,
	                   productInfo->cbCompanyName / 2, &CompanyName, 0, NULL, NULL);
	ConvertFromUnicode(CP_UTF8, 0, (WCHAR*) productInfo->pbProductId,
	                   productInfo->cbProductId / 2, &ProductId, 0, NULL, NULL);
	WLog_INFO(TAG, "ProductInfo:");
	WLog_INFO(TAG, "\tdwVersion: 0x%08"PRIX32"", productInfo->dwVersion);
	WLog_INFO(TAG, "\tCompanyName: %s", CompanyName);
	WLog_INFO(TAG, "\tProductId: %s", ProductId);
	free(CompanyName);
	free(ProductId);
}

static void license_print_scope_list(SCOPE_LIST* scopeList)
{
	int index;
	LICENSE_BLOB* scope;
	WLog_INFO(TAG, "ScopeList (%"PRIu32"):", scopeList->count);

	for (index = 0; index < scopeList->count; index++)
	{
		scope = &scopeList->array[index];
		WLog_INFO(TAG, "\t%s", (char*) scope->data);
	}
}

#endif

/**
 * Read a licensing preamble.\n
 * @msdn{cc240480}
 * @param s stream
 * @param bMsgType license message type
 * @param flags message flags
 * @param wMsgSize message size
 * @return if the operation completed successfully
 */

BOOL license_read_preamble(wStream* s, BYTE* bMsgType, BYTE* flags, UINT16* wMsgSize)
{
	/* preamble (4 bytes) */
	if (Stream_GetRemainingLength(s) < 4)
		return FALSE;

	Stream_Read_UINT8(s, *bMsgType); /* bMsgType (1 byte) */
	Stream_Read_UINT8(s, *flags); /* flags (1 byte) */
	Stream_Read_UINT16(s, *wMsgSize); /* wMsgSize (2 bytes) */
	return TRUE;
}

/**
 * Write a licensing preamble.\n
 * @msdn{cc240480}
 * @param s stream
 * @param bMsgType license message type
 * @param flags message flags
 * @param wMsgSize message size
 */

static BOOL license_write_preamble(wStream* s, BYTE bMsgType, BYTE flags, UINT16 wMsgSize)
{
	if (!Stream_EnsureRemainingCapacity(s, 4))
		return FALSE;

	/* preamble (4 bytes) */
	Stream_Write_UINT8(s, bMsgType); /* bMsgType (1 byte) */
	Stream_Write_UINT8(s, flags); /* flags (1 byte) */
	Stream_Write_UINT16(s, wMsgSize); /* wMsgSize (2 bytes) */
	return TRUE;
}

/**
 * Initialize a license packet stream.\n
 * @param license license module
 * @return stream
 */

wStream* license_send_stream_init(rdpLicense* license)
{
	wStream* s;
	BOOL do_crypt = license->rdp->do_crypt;
	license->rdp->sec_flags = SEC_LICENSE_PKT;

	/**
	 * Encryption of licensing packets is optional even if the rdp security
	 * layer is used. If the peer has not indicated that it is capable of
	 * processing encrypted licensing packets (rdp->do_crypt_license) we turn
	 * off encryption (via rdp->do_crypt) before initializing the rdp stream
	 * and reenable it afterwards.
	 */

	if (do_crypt)
	{
		license->rdp->sec_flags |= SEC_LICENSE_ENCRYPT_CS;
		license->rdp->do_crypt = license->rdp->do_crypt_license;
	}

	s = rdp_send_stream_init(license->rdp);

	if (!s)
		return NULL;

	license->rdp->do_crypt = do_crypt;
	license->PacketHeaderLength = Stream_GetPosition(s);

	if (!Stream_SafeSeek(s, LICENSE_PREAMBLE_LENGTH))
		goto fail;

	return s;
fail:
	Stream_Release(s);
	return NULL;
}

/**
 * Send an RDP licensing packet.\n
 * @msdn{cc240479}
 * @param license license module
 * @param s stream
 */

static BOOL license_send(rdpLicense* license, BYTE type)
{
	BOOL rc = FALSE;
	size_t length;
	BYTE flags;
	UINT16 wMsgSize;
	rdpRdp* rdp;
	wStream* s = license_send_stream_init(license);

	if (!s)
		return FALSE;

	if (!license || !license->rdp)
		goto fail;

	rdp = license->rdp;
	DEBUG_LICENSE("Sending %s Packet", LICENSE_MESSAGE_STRINGS[type & 0x1F]);

	switch (type)
	{
		case NEW_LICENSE_REQUEST:
			if (!license_write_new_license_request_packet(license, s))
				goto fail;

			break;

		case PLATFORM_CHALLENGE_RESPONSE:
			{
				BYTE mac_data[16];
				size_t length = license->PlatformChallenge->length + HWID_LENGTH;
				BYTE* buffer = (BYTE*) malloc(length);

				if (!buffer)
					goto fail;

				CopyMemory(buffer, license->PlatformChallenge->data, license->PlatformChallenge->length);
				CopyMemory(&buffer[license->PlatformChallenge->length], license->HardwareId, HWID_LENGTH);
				rc = security_mac_data(license->MacSaltKey, buffer, length, mac_data);
				free(buffer);

				if (!rc)
					goto fail;

				if (!license_write_platform_challenge_response_packet(license, s, mac_data))
					goto fail;
			}
			break;

		case ERROR_ALERT:
			{
				if (!Stream_EnsureRemainingCapacity(s, 8))
					goto fail;

				Stream_Write_UINT32(s, STATUS_VALID_CLIENT); /* dwErrorCode */
				Stream_Write_UINT32(s, ST_NO_TRANSITION); /* dwStateTransition */

				if (!license_write_binary_blob(s, license->ErrorInfo))
					goto fail;
			}
			break;

		default:
			goto fail;
	}

	length = Stream_GetPosition(s);
	wMsgSize = length - license->PacketHeaderLength;
	Stream_SetPosition(s, license->PacketHeaderLength);
	flags = PREAMBLE_VERSION_3_0;

	/**
	 * Using EXTENDED_ERROR_MSG_SUPPORTED here would cause mstsc to crash when
	 * running in server mode! This flag seems to be incorrectly documented.
	 */

	if (!rdp->settings->ServerMode)
		flags |= EXTENDED_ERROR_MSG_SUPPORTED;

	if (!license_write_preamble(s, type, flags, wMsgSize))
		goto fail;

#ifdef WITH_DEBUG_LICENSE
	WLog_DBG(TAG, "Sending %s Packet, length %"PRIu16"", LICENSE_MESSAGE_STRINGS[type & 0x1F],
	         wMsgSize);
	winpr_HexDump(TAG, WLOG_DEBUG, Stream_Pointer(s) - LICENSE_PREAMBLE_LENGTH, wMsgSize);
#endif
	Stream_SetPosition(s, length);
	rc = rdp_send(rdp, s, MCS_GLOBAL_CHANNEL_ID);
	rdp->sec_flags = 0;
	return rc;
fail:
	Stream_Release(s);
	return FALSE;
}

/**
 * Receive an RDP licensing packet.\n
 * @msdn{cc240479}
 * @param license license module
 * @param s stream
 * @return if the operation completed successfully
 */

int license_recv(rdpLicense* license, wStream* s)
{
	BYTE flags;
	BYTE bMsgType;
	UINT16 wMsgSize;
	UINT16 length;
	UINT16 channelId;
	UINT16 securityFlags = 0;

	if (!rdp_read_header(license->rdp, s, &length, &channelId))
	{
		WLog_ERR(TAG, "Incorrect RDP header.");
		return -1;
	}

	if (!rdp_read_security_header(s, &securityFlags, &length))
		return -1;

	if (securityFlags & SEC_ENCRYPT)
	{
		if (!rdp_decrypt(license->rdp, s, length, securityFlags))
		{
			WLog_ERR(TAG, "rdp_decrypt failed");
			return -1;
		}
	}

	if (!(securityFlags & SEC_LICENSE_PKT))
	{
		int status;

		if (!(securityFlags & SEC_ENCRYPT))
			Stream_Rewind(s, RDP_SECURITY_HEADER_LENGTH);

		status = rdp_recv_out_of_sequence_pdu(license->rdp, s);

		if (status < 0)
		{
			WLog_ERR(TAG, "unexpected license packet.");
			return status;
		}

		return 0;
	}

	if (!license_read_preamble(s, &bMsgType, &flags, &wMsgSize)) /* preamble (4 bytes) */
		return -1;

	DEBUG_LICENSE("Receiving %s Packet", LICENSE_MESSAGE_STRINGS[bMsgType & 0x1F]);

	switch (bMsgType)
	{
		case LICENSE_REQUEST:
			if (!license_read_license_request_packet(license, s))
				return -1;

			if (!license_send_new_license_request_packet(license))
				return -1;

			break;

		case PLATFORM_CHALLENGE:
			if (!license_read_platform_challenge_packet(license, s))
				return -1;

			if (!license_send_platform_challenge_response_packet(license))
				return -1;

			break;

		case NEW_LICENSE:
			license_read_new_license_packet(license, s);
			break;

		case UPGRADE_LICENSE:
			license_read_upgrade_license_packet(license, s);
			break;

		case ERROR_ALERT:
			if (!license_read_error_alert_packet(license, s))
				return -1;

			break;

		default:
			WLog_ERR(TAG, "invalid bMsgType:%"PRIu8"", bMsgType);
			return FALSE;
	}

	return 0;
}

void license_generate_randoms(rdpLicense* license)
{
	ZeroMemory(license->ClientRandom, CLIENT_RANDOM_LENGTH); /* ClientRandom */
	ZeroMemory(license->PremasterSecret, PREMASTER_SECRET_LENGTH); /* PremasterSecret */
#ifndef LICENSE_NULL_CLIENT_RANDOM
	winpr_RAND(license->ClientRandom, CLIENT_RANDOM_LENGTH); /* ClientRandom */
#endif
#ifndef LICENSE_NULL_PREMASTER_SECRET
	winpr_RAND(license->PremasterSecret, PREMASTER_SECRET_LENGTH); /* PremasterSecret */
#endif
}

/**
 * Generate License Cryptographic Keys.
 * @param license license module
 */

BOOL license_generate_keys(rdpLicense* license)
{
	BOOL ret;

	if (
	    /* MasterSecret */
	    !security_master_secret(license->PremasterSecret, license->ClientRandom,
	                            license->ServerRandom, license->MasterSecret) ||
	    /* SessionKeyBlob */
	    !security_session_key_blob(license->MasterSecret, license->ClientRandom,
	                               license->ServerRandom, license->SessionKeyBlob))
	{
		return FALSE;
	}

	security_mac_salt_key(license->SessionKeyBlob, license->ClientRandom,
	                      license->ServerRandom, license->MacSaltKey); /* MacSaltKey */
	ret = security_licensing_encryption_key(license->SessionKeyBlob, license->ClientRandom,
	                                        license->ServerRandom, license->LicensingEncryptionKey); /* LicensingEncryptionKey */
#ifdef WITH_DEBUG_LICENSE
	WLog_DBG(TAG, "ClientRandom:");
	winpr_HexDump(TAG, WLOG_DEBUG, license->ClientRandom, CLIENT_RANDOM_LENGTH);
	WLog_DBG(TAG, "ServerRandom:");
	winpr_HexDump(TAG, WLOG_DEBUG, license->ServerRandom, SERVER_RANDOM_LENGTH);
	WLog_DBG(TAG, "PremasterSecret:");
	winpr_HexDump(TAG, WLOG_DEBUG, license->PremasterSecret, PREMASTER_SECRET_LENGTH);
	WLog_DBG(TAG, "MasterSecret:");
	winpr_HexDump(TAG, WLOG_DEBUG, license->MasterSecret, MASTER_SECRET_LENGTH);
	WLog_DBG(TAG, "SessionKeyBlob:");
	winpr_HexDump(TAG, WLOG_DEBUG, license->SessionKeyBlob, SESSION_KEY_BLOB_LENGTH);
	WLog_DBG(TAG, "MacSaltKey:");
	winpr_HexDump(TAG, WLOG_DEBUG, license->MacSaltKey, MAC_SALT_KEY_LENGTH);
	WLog_DBG(TAG, "LicensingEncryptionKey:");
	winpr_HexDump(TAG, WLOG_DEBUG, license->LicensingEncryptionKey, LICENSING_ENCRYPTION_KEY_LENGTH);
#endif
	return ret;
}

/**
 * Generate Unique Hardware Identifier (CLIENT_HARDWARE_ID).\n
 * @param license license module
 */

BOOL license_generate_hwid(rdpLicense* license)
{
	BYTE macAddress[6];
	ZeroMemory(macAddress, sizeof(macAddress));
	ZeroMemory(license->HardwareId, HWID_LENGTH);

	/* Allow FIPS override for use of MD5 here, really this does not have to be MD5 as we are just taking a MD5 hash of the 6 bytes of 0's(macAddress) */
	/* and filling in the Data1-Data4 fields of the CLIENT_HARDWARE_ID structure(from MS-RDPELE section 2.2.2.3.1). This is for RDP licensing packets */
	/* which will already be encrypted under FIPS, so the use of MD5 here is not for sensitive data protection. */
	if (!winpr_Digest_Allow_FIPS(WINPR_MD_MD5, macAddress, sizeof(macAddress),
	                             &license->HardwareId[HWID_PLATFORM_ID_LENGTH], WINPR_MD5_DIGEST_LENGTH))
		return FALSE;

	return TRUE;
}

BOOL license_get_server_rsa_public_key(rdpLicense* license)
{
	BYTE* Exponent;
	BYTE* Modulus;
	int ModulusLength;
	rdpSettings* settings = license->rdp->settings;

	if (license->ServerCertificate->length < 1)
	{
		if (!certificate_read_server_certificate(license->certificate,
		        settings->ServerCertificate, settings->ServerCertificateLength))
			return FALSE;
	}

	Exponent = license->certificate->cert_info.exponent;
	Modulus = license->certificate->cert_info.Modulus;
	ModulusLength = license->certificate->cert_info.ModulusLength;
	CopyMemory(license->Exponent, Exponent, 4);
	license->ModulusLength = ModulusLength;
	license->Modulus = (BYTE*) malloc(ModulusLength);

	if (!license->Modulus)
		return FALSE;

	CopyMemory(license->Modulus, Modulus, ModulusLength);
	return TRUE;
}

BOOL license_encrypt_premaster_secret(rdpLicense* license)
{
	BYTE* EncryptedPremasterSecret;

	if (!license_get_server_rsa_public_key(license))
		return FALSE;

#ifdef WITH_DEBUG_LICENSE
	WLog_DBG(TAG, "Modulus (%"PRIu32" bits):", license->ModulusLength * 8);
	winpr_HexDump(TAG, WLOG_DEBUG, license->Modulus, license->ModulusLength);
	WLog_DBG(TAG, "Exponent:");
	winpr_HexDump(TAG, WLOG_DEBUG, license->Exponent, 4);
#endif
	EncryptedPremasterSecret = (BYTE*) calloc(1, license->ModulusLength);

	if (!EncryptedPremasterSecret)
		return FALSE;

	license->EncryptedPremasterSecret->type = BB_RANDOM_BLOB;
	license->EncryptedPremasterSecret->length = PREMASTER_SECRET_LENGTH;
#ifndef LICENSE_NULL_PREMASTER_SECRET
	license->EncryptedPremasterSecret->length =
	    crypto_rsa_public_encrypt(license->PremasterSecret, PREMASTER_SECRET_LENGTH,
	                              license->ModulusLength, license->Modulus, license->Exponent, EncryptedPremasterSecret);
#endif
	license->EncryptedPremasterSecret->data = EncryptedPremasterSecret;
	return TRUE;
}

BOOL license_decrypt_platform_challenge(rdpLicense* license)
{
	BOOL rc;
	WINPR_RC4_CTX* rc4;
	license->PlatformChallenge->data = (BYTE*)malloc(license->EncryptedPlatformChallenge->length);

	if (!license->PlatformChallenge->data)
		return FALSE;

	license->PlatformChallenge->length = license->EncryptedPlatformChallenge->length;

	/* Allow FIPS override for use of RC4 here, this is only used for decrypting the MACData field of the */
	/* Server Platform Challenge packet (from MS-RDPELE section 2.2.2.4). This is for RDP licensing packets */
	/* which will already be encrypted under FIPS, so the use of RC4 here is not for sensitive data protection. */
	if ((rc4 = winpr_RC4_New_Allow_FIPS(license->LicensingEncryptionKey,
	                                    LICENSING_ENCRYPTION_KEY_LENGTH)) == NULL)
	{
		free(license->PlatformChallenge->data);
		license->PlatformChallenge->data = NULL;
		license->PlatformChallenge->length = 0;
		return FALSE;
	}

	rc = winpr_RC4_Update(rc4, license->EncryptedPlatformChallenge->length,
	                      license->EncryptedPlatformChallenge->data,
	                      license->PlatformChallenge->data);
	winpr_RC4_Free(rc4);
	return rc;
}

/**
 * Read Product Information (PRODUCT_INFO).\n
 * @msdn{cc241915}
 * @param s stream
 * @param productInfo product information
 */

BOOL license_read_product_info(wStream* s, LICENSE_PRODUCT_INFO* productInfo)
{
	if (Stream_GetRemainingLength(s) < 8)
		return FALSE;

	Stream_Read_UINT32(s, productInfo->dwVersion); /* dwVersion (4 bytes) */
	Stream_Read_UINT32(s, productInfo->cbCompanyName); /* cbCompanyName (4 bytes) */

	/* Name must be >0, but there is no upper limit defined, use UINT32_MAX */
	if ((productInfo->cbCompanyName < 2) || (productInfo->cbCompanyName % 2 != 0))
		return FALSE;

	if (Stream_GetRemainingLength(s) < productInfo->cbCompanyName)
		return FALSE;

	productInfo->pbProductId = NULL;
	productInfo->pbCompanyName = (BYTE*) malloc(productInfo->cbCompanyName);

	if (!productInfo->pbCompanyName)
		return FALSE;

	Stream_Read(s, productInfo->pbCompanyName, productInfo->cbCompanyName);

	if (Stream_GetRemainingLength(s) < 4)
		goto out_fail;

	Stream_Read_UINT32(s, productInfo->cbProductId); /* cbProductId (4 bytes) */

	if ((productInfo->cbProductId < 2) || (productInfo->cbProductId % 2 != 0))
		goto out_fail;

	if (Stream_GetRemainingLength(s) < productInfo->cbProductId)
		goto out_fail;

	productInfo->pbProductId = (BYTE*) malloc(productInfo->cbProductId);

	if (!productInfo->pbProductId)
		goto out_fail;

	Stream_Read(s, productInfo->pbProductId, productInfo->cbProductId);
	return TRUE;
out_fail:
	free(productInfo->pbCompanyName);
	free(productInfo->pbProductId);
	productInfo->pbCompanyName = NULL;
	productInfo->pbProductId = NULL;
	return FALSE;
}

/**
 * Allocate New Product Information (LICENSE_PRODUCT_INFO).\n
 * @msdn{cc241915}
 * @return new product information
 */

LICENSE_PRODUCT_INFO* license_new_product_info()
{
	LICENSE_PRODUCT_INFO* productInfo;
	productInfo = (LICENSE_PRODUCT_INFO*) malloc(sizeof(LICENSE_PRODUCT_INFO));

	if (!productInfo)
		return NULL;

	productInfo->dwVersion = 0;
	productInfo->cbCompanyName = 0;
	productInfo->pbCompanyName = NULL;
	productInfo->cbProductId = 0;
	productInfo->pbProductId = NULL;
	return productInfo;
}

/**
 * Free Product Information (LICENSE_PRODUCT_INFO).\n
 * @msdn{cc241915}
 * @param productInfo product information
 */

void license_free_product_info(LICENSE_PRODUCT_INFO* productInfo)
{
	if (productInfo)
	{
		free(productInfo->pbCompanyName);
		free(productInfo->pbProductId);
		free(productInfo);
	}
}

/**
 * Read License Binary Blob (LICENSE_BINARY_BLOB).\n
 * @msdn{cc240481}
 * @param s stream
 * @param blob license binary blob
 */

BOOL license_read_binary_blob(wStream* s, LICENSE_BLOB* blob)
{
	UINT16 wBlobType;

	if (Stream_GetRemainingLength(s) < 4)
		return FALSE;

	Stream_Read_UINT16(s, wBlobType); /* wBlobType (2 bytes) */
	Stream_Read_UINT16(s, blob->length); /* wBlobLen (2 bytes) */

	if (Stream_GetRemainingLength(s) < blob->length)
		return FALSE;

	/*
	 * Server can choose to not send data by setting length to 0.
	 * If so, it may not bother to set the type, so shortcut the warning
	 */
	if ((blob->type != BB_ANY_BLOB) && (blob->length == 0))
		return TRUE;

	if ((blob->type != wBlobType) && (blob->type != BB_ANY_BLOB))
	{
		WLog_ERR(TAG, "license binary blob type (0x%"PRIx16") does not match expected type (0x%"PRIx16").",
		         wBlobType, blob->type);
	}

	blob->type = wBlobType;
	blob->data = (BYTE*) malloc(blob->length);

	if (!blob->data)
		return FALSE;

	Stream_Read(s, blob->data, blob->length); /* blobData */
	return TRUE;
}

/**
 * Write License Binary Blob (LICENSE_BINARY_BLOB).\n
 * @msdn{cc240481}
 * @param s stream
 * @param blob license binary blob
 */

BOOL license_write_binary_blob(wStream* s, LICENSE_BLOB* blob)
{
	if (!Stream_EnsureRemainingCapacity(s, blob->length +  4))
	{
		Stream_Release(s);
		return FALSE;
	}

	Stream_Write_UINT16(s, blob->type); /* wBlobType (2 bytes) */
	Stream_Write_UINT16(s, blob->length); /* wBlobLen (2 bytes) */

	if (blob->length > 0)
		Stream_Write(s, blob->data, blob->length); /* blobData */

	return TRUE;
}

static BOOL license_write_encrypted_premaster_secret_blob(wStream* s, LICENSE_BLOB* blob,
        UINT32 ModulusLength)
{
	UINT32 length;
	length = ModulusLength + 8;

	if (blob->length > ModulusLength)
	{
		WLog_ERR(TAG, "license_write_encrypted_premaster_secret_blob: invalid blob");
		return FALSE;
	}

	if (!Stream_EnsureRemainingCapacity(s, length + 4))
		return FALSE;

	Stream_Write_UINT16(s, blob->type); /* wBlobType (2 bytes) */
	Stream_Write_UINT16(s, length); /* wBlobLen (2 bytes) */

	if (blob->length > 0)
		Stream_Write(s, blob->data, blob->length); /* blobData */

	Stream_Zero(s, length - blob->length);
	return TRUE;
}

/**
 * Allocate New License Binary Blob (LICENSE_BINARY_BLOB).\n
 * @msdn{cc240481}
 * @return new license binary blob
 */

LICENSE_BLOB* license_new_binary_blob(UINT16 type)
{
	LICENSE_BLOB* blob;
	blob = (LICENSE_BLOB*) calloc(1, sizeof(LICENSE_BLOB));

	if (blob)
		blob->type = type;

	return blob;
}

/**
 * Free License Binary Blob (LICENSE_BINARY_BLOB).\n
 * @msdn{cc240481}
 * @param blob license binary blob
 */

void license_free_binary_blob(LICENSE_BLOB* blob)
{
	if (blob)
	{
		free(blob->data);
		free(blob);
	}
}

/**
 * Read License Scope List (SCOPE_LIST).\n
 * @msdn{cc241916}
 * @param s stream
 * @param scopeList scope list
 */

BOOL license_read_scope_list(wStream* s, SCOPE_LIST* scopeList)
{
	UINT32 i;
	UINT32 scopeCount;

	if (Stream_GetRemainingLength(s) < 4)
		return FALSE;

	Stream_Read_UINT32(s, scopeCount); /* ScopeCount (4 bytes) */

	if (scopeCount > Stream_GetRemainingLength(s) / 4)  /* every blob is at least 4 bytes */
		return FALSE;

	scopeList->count = scopeCount;
	scopeList->array = (LICENSE_BLOB*) calloc(scopeCount, sizeof(LICENSE_BLOB));

	if (!scopeList->array)
		return FALSE;

	/* ScopeArray */
	for (i = 0; i < scopeCount; i++)
	{
		scopeList->array[i].type = BB_SCOPE_BLOB;

		if (!license_read_binary_blob(s, &scopeList->array[i]))
			return FALSE;
	}

	return TRUE;
}

/**
 * Allocate New License Scope List (SCOPE_LIST).\n
 * @msdn{cc241916}
 * @return new scope list
 */

SCOPE_LIST* license_new_scope_list()
{
	return (SCOPE_LIST*) calloc(1, sizeof(SCOPE_LIST));
}

/**
 * Free License Scope List (SCOPE_LIST).\n
 * @msdn{cc241916}
 * @param scopeList scope list
 */

void license_free_scope_list(SCOPE_LIST* scopeList)
{
	UINT32 i;

	if (!scopeList)
		return;

	/*
	 * We must NOT call license_free_binary_blob() on each scopelist->array[i] element,
	 * because scopelist->array was allocated at once, by a single call to malloc. The elements
	 * it contains cannot be deallocated separately then.
	 * To make things clean, we must deallocate each scopelist->array[].data,
	 * and finish by deallocating scopelist->array with a single call to free().
	 */
	for (i = 0; i < scopeList->count; i++)
	{
		free(scopeList->array[i].data);
	}

	free(scopeList->array);
	free(scopeList);
}

/**
 * Read a LICENSE_REQUEST packet.\n
 * @msdn{cc241914}
 * @param license license module
 * @param s stream
 */

BOOL license_read_license_request_packet(rdpLicense* license, wStream* s)
{
	/* ServerRandom (32 bytes) */
	if (Stream_GetRemainingLength(s) < 32)
		return FALSE;

	Stream_Read(s, license->ServerRandom, 32);

	/* ProductInfo */
	if (!license_read_product_info(s, license->ProductInfo))
		return FALSE;

	/* KeyExchangeList */
	if (!license_read_binary_blob(s, license->KeyExchangeList))
		return FALSE;

	/* ServerCertificate */
	if (!license_read_binary_blob(s, license->ServerCertificate))
		return FALSE;

	/* ScopeList */
	if (!license_read_scope_list(s, license->ScopeList))
		return FALSE;

	/* Parse Server Certificate */
	if (!certificate_read_server_certificate(license->certificate,
	        license->ServerCertificate->data, license->ServerCertificate->length))
		return FALSE;

	if (!license_generate_keys(license) || !license_generate_hwid(license) ||
	    !license_encrypt_premaster_secret(license))
		return FALSE;

#ifdef WITH_DEBUG_LICENSE
	WLog_DBG(TAG, "ServerRandom:");
	winpr_HexDump(TAG, WLOG_DEBUG, license->ServerRandom, 32);
	license_print_product_info(license->ProductInfo);
	license_print_scope_list(license->ScopeList);
#endif
	return TRUE;
}

/**
 * Read a PLATFORM_CHALLENGE packet.\n
 * @msdn{cc241921}
 * @param license license module
 * @param s stream
 */

BOOL license_read_platform_challenge_packet(rdpLicense* license, wStream* s)
{
	BYTE MacData[16];
	UINT32 ConnectFlags = 0;
	DEBUG_LICENSE("Receiving Platform Challenge Packet");

	if (Stream_GetRemainingLength(s) < 4)
		return FALSE;

	Stream_Read_UINT32(s, ConnectFlags); /* ConnectFlags, Reserved (4 bytes) */
	/* EncryptedPlatformChallenge */
	license->EncryptedPlatformChallenge->type = BB_ANY_BLOB;

	if (!license_read_binary_blob(s, license->EncryptedPlatformChallenge))
		return FALSE;

	license->EncryptedPlatformChallenge->type = BB_ENCRYPTED_DATA_BLOB;

	if (Stream_GetRemainingLength(s) < 16)
		return FALSE;

	Stream_Read(s, MacData, 16); /* MACData (16 bytes) */

	if (!license_decrypt_platform_challenge(license))
		return FALSE;

#ifdef WITH_DEBUG_LICENSE
	WLog_DBG(TAG, "ConnectFlags: 0x%08"PRIX32"", ConnectFlags);
	WLog_DBG(TAG, "EncryptedPlatformChallenge:");
	winpr_HexDump(TAG, WLOG_DEBUG, license->EncryptedPlatformChallenge->data,
	              license->EncryptedPlatformChallenge->length);
	WLog_DBG(TAG, "PlatformChallenge:");
	winpr_HexDump(TAG, WLOG_DEBUG, license->PlatformChallenge->data,
	              license->PlatformChallenge->length);
	WLog_DBG(TAG, "MacData:");
	winpr_HexDump(TAG, WLOG_DEBUG, MacData, 16);
#endif
	return TRUE;
}

/**
 * Read a NEW_LICENSE packet.\n
 * @msdn{cc241926}
 * @param license license module
 * @param s stream
 */

void license_read_new_license_packet(rdpLicense* license, wStream* s)
{
	DEBUG_LICENSE("Receiving New License Packet");
	license->state = LICENSE_STATE_COMPLETED;
}

/**
 * Read an UPGRADE_LICENSE packet.\n
 * @msdn{cc241924}
 * @param license license module
 * @param s stream
 */

void license_read_upgrade_license_packet(rdpLicense* license, wStream* s)
{
	DEBUG_LICENSE("Receiving Upgrade License Packet");
	license->state = LICENSE_STATE_COMPLETED;
}

/**
 * Read an ERROR_ALERT packet.\n
 * @msdn{cc240482}
 * @param license license module
 * @param s stream
 */

BOOL license_read_error_alert_packet(rdpLicense* license, wStream* s)
{
	UINT32 dwErrorCode;
	UINT32 dwStateTransition;

	if (Stream_GetRemainingLength(s) < 8)
		return FALSE;

	Stream_Read_UINT32(s, dwErrorCode); /* dwErrorCode (4 bytes) */
	Stream_Read_UINT32(s, dwStateTransition); /* dwStateTransition (4 bytes) */

	if (!license_read_binary_blob(s, license->ErrorInfo)) /* bbErrorInfo */
		return FALSE;

#ifdef WITH_DEBUG_LICENSE
	WLog_DBG(TAG, "dwErrorCode: %s, dwStateTransition: %s",
	         error_codes[dwErrorCode], state_transitions[dwStateTransition]);
#endif

	if (dwErrorCode == STATUS_VALID_CLIENT)
	{
		license->state = LICENSE_STATE_COMPLETED;
		return TRUE;
	}

	switch (dwStateTransition)
	{
		case ST_TOTAL_ABORT:
			license->state = LICENSE_STATE_ABORTED;
			break;

		case ST_NO_TRANSITION:
			license->state = LICENSE_STATE_COMPLETED;
			break;

		case ST_RESET_PHASE_TO_START:
			license->state = LICENSE_STATE_AWAIT;
			break;

		case ST_RESEND_LAST_MESSAGE:
			break;

		default:
			break;
	}

	return TRUE;
}

/**
 * Write a NEW_LICENSE_REQUEST packet.\n
 * @msdn{cc241918}
 * @param license license module
 * @param s stream
 */

BOOL license_write_new_license_request_packet(rdpLicense* license, wStream* s)
{
	UINT32 PlatformId;
	UINT32 PreferredKeyExchangeAlg = KEY_EXCHANGE_ALG_RSA;
	PlatformId = CLIENT_OS_ID_WINNT_POST_52 | CLIENT_IMAGE_ID_MICROSOFT;
	Stream_Write_UINT32(s, PreferredKeyExchangeAlg); /* PreferredKeyExchangeAlg (4 bytes) */
	Stream_Write_UINT32(s, PlatformId); /* PlatformId (4 bytes) */
	Stream_Write(s, license->ClientRandom, 32); /* ClientRandom (32 bytes) */

	/* EncryptedPremasterSecret */
	if (!license_write_encrypted_premaster_secret_blob(s, license->EncryptedPremasterSecret,
	        license->ModulusLength) ||
	    /* ClientUserName */
	    !license_write_binary_blob(s, license->ClientUserName) ||
	    /* ClientMachineName */
	    !license_write_binary_blob(s, license->ClientMachineName))
	{
		Stream_Release(s);
		return FALSE;
	}

#ifdef WITH_DEBUG_LICENSE
	WLog_DBG(TAG, "PreferredKeyExchangeAlg: 0x%08"PRIX32"", PreferredKeyExchangeAlg);
	WLog_DBG(TAG, "ClientRandom:");
	winpr_HexDump(TAG, WLOG_DEBUG, license->ClientRandom, 32);
	WLog_DBG(TAG, "EncryptedPremasterSecret");
	winpr_HexDump(TAG, WLOG_DEBUG, license->EncryptedPremasterSecret->data,
	              license->EncryptedPremasterSecret->length);
	WLog_DBG(TAG, "ClientUserName (%"PRIu16"): %s", license->ClientUserName->length,
	         (char*) license->ClientUserName->data);
	WLog_DBG(TAG, "ClientMachineName (%"PRIu16"): %s", license->ClientMachineName->length,
	         (char*) license->ClientMachineName->data);
#endif
	return TRUE;
}

/**
 * Send a NEW_LICENSE_REQUEST packet.\n
 * @msdn{cc241918}
 * @param license license module
 */

BOOL license_send_new_license_request_packet(rdpLicense* license)
{
	char* username;
	DEBUG_LICENSE("Sending New License Packet");

	if (license->rdp->settings->Username != NULL)
		username = license->rdp->settings->Username;
	else
		username = "username";

	license->ClientUserName->data = (BYTE*) username;
	license->ClientUserName->length = strlen(username) + 1;
	license->ClientMachineName->data = (BYTE*) license->rdp->settings->ClientHostname;
	license->ClientMachineName->length = strlen(license->rdp->settings->ClientHostname) + 1;

	if (!license_send(license, NEW_LICENSE_REQUEST))
		return FALSE;

	license->ClientUserName->data = NULL;
	license->ClientUserName->length = 0;
	license->ClientMachineName->data = NULL;
	license->ClientMachineName->length = 0;
	return TRUE;
}

/**
 * Write Client Challenge Response Packet.\n
 * @msdn{cc241922}
 * @param license license module
 * @param s stream
 * @param mac_data signature
 */

BOOL license_write_platform_challenge_response_packet(rdpLicense* license, wStream* s,
        BYTE* macData)
{
	if (!license_write_binary_blob(s, license->EncryptedPlatformChallenge) ||
	    /* EncryptedPlatformChallengeResponse */
	    !license_write_binary_blob(s, license->EncryptedHardwareId) || /* EncryptedHWID */
	    !Stream_EnsureRemainingCapacity(s, 16))
	{
		Stream_Release(s);
		return FALSE;
	}

	Stream_Write(s, macData, 16); /* MACData */
	return TRUE;
}

/**
 * Send Client Challenge Response Packet.\n
 * @msdn{cc241922}
 * @param license license module
 */

BOOL license_send_platform_challenge_response_packet(rdpLicense* license)
{
	BYTE* buffer;
	WINPR_RC4_CTX* rc4;
	BOOL status;
	DEBUG_LICENSE("Sending Platform Challenge Response Packet");
	license->EncryptedPlatformChallenge->type = BB_DATA_BLOB;
	/* Allow FIPS override for use of RC4 here, this is only used for encrypting the EncryptedHWID field of the */
	/* Client Platform Challenge Response packet (from MS-RDPELE section 2.2.2.5). This is for RDP licensing packets */
	/* which will already be encrypted under FIPS, so the use of RC4 here is not for sensitive data protection. */
	rc4 = winpr_RC4_New_Allow_FIPS(license->LicensingEncryptionKey,
	                               LICENSING_ENCRYPTION_KEY_LENGTH);

	if (!rc4)
		return FALSE;

	buffer = (BYTE*) malloc(HWID_LENGTH);

	if (!buffer)
		return FALSE;

	status = winpr_RC4_Update(rc4, HWID_LENGTH, license->HardwareId, buffer);
	winpr_RC4_Free(rc4);

	if (!status)
	{
		free(buffer);
		return FALSE;
	}

	license->EncryptedHardwareId->type = BB_DATA_BLOB;
	license->EncryptedHardwareId->data = buffer;
	license->EncryptedHardwareId->length = HWID_LENGTH;
#ifdef WITH_DEBUG_LICENSE
	WLog_DBG(TAG, "LicensingEncryptionKey:");
	winpr_HexDump(TAG, WLOG_DEBUG, license->LicensingEncryptionKey, 16);
	WLog_DBG(TAG, "HardwareId:");
	winpr_HexDump(TAG, WLOG_DEBUG, license->HardwareId, HWID_LENGTH);
	WLog_DBG(TAG, "EncryptedHardwareId:");
	winpr_HexDump(TAG, WLOG_DEBUG, license->EncryptedHardwareId->data, HWID_LENGTH);
#endif
	return license_send(license, PLATFORM_CHALLENGE_RESPONSE);
}

/**
 * Send Server License Error - Valid Client Packet.\n
 * @msdn{cc241922}
 * @param license license module
 */

BOOL license_send_valid_client_error_packet(rdpLicense* license)
{
	wStream* s = license_send_stream_init(license);

	if (!s)
		return FALSE;

	DEBUG_LICENSE("Sending Error Alert Packet");
	return license_send(license, ERROR_ALERT);
}

/**
 * Instantiate new license module.
 * @param rdp RDP module
 * @return new license module
 */

rdpLicense* license_new(rdpRdp* rdp)
{
	rdpLicense* license;
	license = (rdpLicense*) calloc(1, sizeof(rdpLicense));

	if (!license)
		return NULL;

	license->rdp = rdp;
	license->state = LICENSE_STATE_AWAIT;

	if (!(license->certificate = certificate_new()))
		goto out_error;

	if (!(license->ProductInfo = license_new_product_info()))
		goto out_error;

	if (!(license->ErrorInfo = license_new_binary_blob(BB_ERROR_BLOB)))
		goto out_error;

	if (!(license->KeyExchangeList = license_new_binary_blob(BB_KEY_EXCHG_ALG_BLOB)))
		goto out_error;

	if (!(license->ServerCertificate = license_new_binary_blob(BB_CERTIFICATE_BLOB)))
		goto out_error;

	if (!(license->ClientUserName = license_new_binary_blob(BB_CLIENT_USER_NAME_BLOB)))
		goto out_error;

	if (!(license->ClientMachineName = license_new_binary_blob(BB_CLIENT_MACHINE_NAME_BLOB)))
		goto out_error;

	if (!(license->PlatformChallenge = license_new_binary_blob(BB_ANY_BLOB)))
		goto out_error;

	if (!(license->EncryptedPlatformChallenge = license_new_binary_blob(BB_ANY_BLOB)))
		goto out_error;

	if (!(license->EncryptedPremasterSecret = license_new_binary_blob(BB_ANY_BLOB)))
		goto out_error;

	if (!(license->EncryptedHardwareId = license_new_binary_blob(BB_ENCRYPTED_DATA_BLOB)))
		goto out_error;

	if (!(license->ScopeList = license_new_scope_list()))
		goto out_error;

	license_generate_randoms(license);
	return license;
out_error:
	license_free(license);
	return NULL;
}

/**
 * Free license module.
 * @param license license module to be freed
 */

void license_free(rdpLicense* license)
{
	if (license)
	{
		free(license->Modulus);
		certificate_free(license->certificate);
		license_free_product_info(license->ProductInfo);
		license_free_binary_blob(license->ErrorInfo);
		license_free_binary_blob(license->KeyExchangeList);
		license_free_binary_blob(license->ServerCertificate);
		license_free_binary_blob(license->ClientUserName);
		license_free_binary_blob(license->ClientMachineName);
		license_free_binary_blob(license->PlatformChallenge);
		license_free_binary_blob(license->EncryptedPlatformChallenge);
		license_free_binary_blob(license->EncryptedPremasterSecret);
		license_free_binary_blob(license->EncryptedHardwareId);
		license_free_scope_list(license->ScopeList);
		free(license);
	}
}