/*

* Copyright (C) 2021 Yee Young Han <[email protected]> (http://blog.naver.com/websearch)

*

* This program is free software; you can redistribute it and/or modify

* it under the terms of the GNU General Public License as published by

* the Free Software Foundation; either version 3 of the License, or

* (at your option) any later version.

*

* This program is distributed in the hope that it will be useful,

* but WITHOUT ANY WARRANTY; without even the implied warranty of

* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

* GNU General Public License for more details.

*

* You should have received a copy of the GNU General Public License

* along with this program; if not, write to the Free Software

* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

*/

/**

* @ingroup HttpStack

* @brief WebSocket 클라이언트로 데이터를 전송한다.

* @param pszClientIp WebSocket 클라이언트 IP 주소

* @param iClientPort WebSocket 클라이언트 포트 번호

* @param pszData WebSocket 으로 전송할 payload 데이터

* @param iDataLen WebSocket 으로 전송할 payload 데이터 길이

* @returns 성공하면 true 를 리턴하고 그렇지 않으면 false 를 리턴한다.

*/

bool CHttpStack::SendWebSocketPacket( const char * pszClientIp, int iClientPort, const char * pszData, int iDataLen )

{

int iPacketLen = 0;

if( iDataLen > 65536 )

{

iPacketLen = 2 + 8 + iDataLen;

}

else if( iDataLen > 125 )

{

iPacketLen = 2 + 2 + iDataLen;

}

else

{

iPacketLen = 2 + iDataLen;

}

char * pszPacket = (char *)malloc( iPacketLen );

if( pszPacket == NULL )

{

CLog::Print( LOG_ERROR, "%s malloc error", __FUNCTION__ );

return false;

}

pszPacket[0] = (uint8_t)0x81;

int iPayLoadPos = 2;

if( iDataLen > 65536 )

{

pszPacket[1] = 127;

uint64_t lDataLen = iDataLen;

lDataLen = htonll( lDataLen );

memcpy( pszPacket + 2, &lDataLen, 8 );

iPayLoadPos = 2 + 8;

}

else if( iDataLen > 125 )

{

pszPacket[1] = 126;

uint16_t sDataLen = iDataLen;

sDataLen = htons( sDataLen );

memcpy( pszPacket + 2, &sDataLen, 2 );

iPayLoadPos = 2 + 2;

}

else

{

pszPacket[1] = iDataLen;

}

memcpy( pszPacket + iPayLoadPos, pszData, iDataLen );

bool bRes = m_clsTcpStack.Send( pszClientIp, iClientPort, pszPacket, iPacketLen, false );

free( pszPacket );

return bRes;

}

bool CHttpStack::RecvPacketWebSocket( char * pszPacket, int iPacketLen, CTcpSessionInfo * pclsSessionInfo, CHttpStackSession * pclsApp )

{

// WebSocket 프로토콜

CWebSocketPacketHeader clsHeader;

std::string strData;

pclsApp->m_clsWsPacket.AddPacket( pszPacket, iPacketLen );

while( pclsApp->m_clsWsPacket.GetData( clsHeader, strData ) )

{

if( clsHeader.m_iOpCode == 1 || clsHeader.m_iOpCode == 2 )

{

if( m_pclsCallBack->WebSocketData( pclsSessionInfo->m_strIp.c_str(), pclsSessionInfo->m_iPort, strData ) == false )

{

return false;

}

}

else if( clsHeader.m_iOpCode == 8 )

{

char szPacket[255];

memset( szPacket, 0, sizeof(szPacket) );

szPacket[0] = (uint8_t)0x88;

iPacketLen = 2;

if( pclsSessionInfo->Send( szPacket, iPacketLen ) == false )

{

CLog::Print( LOG_ERROR, "%s Send error", __FUNCTION__ );

return false;

}

}

else if( clsHeader.m_iOpCode == 9 )

{

char szPacket[255];

memset( szPacket, 0, sizeof(szPacket) );

szPacket[0] = (uint8_t)0x8A;

iPacketLen = 2;

if( strData.empty() == false && strData.length() < 125 )

{

szPacket[1] = (uint8_t)strData.length();

memcpy( szPacket + 2, strData.c_str(), strData.length() );

iPacketLen += strData.length();

}

if( pclsSessionInfo->Send( szPacket, iPacketLen ) == false )

{

CLog::Print( LOG_ERROR, "%s Send error", __FUNCTION__ );

return false;

}

}

}

return true;

}

/**

* @ingroup HttpStack

* @brief WebSocket 연결을 위한 HTTP 요청 메시지에 대한 HTTP 응답 메시지를 생성한다.

* @param pclsRecv 수신된 HTTP 요청 메시지

* @param pclsSend 전송할 HTTP 응답 메시지

* @returns 성공하면 true 를 리턴하고 실패하면 false 를 리턴한다.

*/

bool CHttpStack::MakeWebSocketResponse( CHttpMessage * pclsRecv, CHttpMessage * pclsSend )

{

CHttpHeader * pclsHeader = pclsRecv->GetHeader( "Sec-WebSocket-Key" );

if( pclsHeader == NULL )

{

CLog::Print( LOG_ERROR, "%s Sec-WebSocket-Key is not found", __FUNCTION__ );

return false;

}

std::string strKey = pclsHeader->m_strValue;

pclsSend->m_iStatusCode = HTTP_SWITCHING_PROTOCOLS;

pclsSend->AddHeader( "Upgrade", "websocket" );

pclsSend->AddHeader( "Connection", "Upgrade" );

EVP_MD_CTX sttCtx;

uint8_t szDigest[EVP_MAX_MD_SIZE];

char szOutput[EVP_MAX_MD_SIZE*2+1];

uint32_t iDigestLen;

memset( szDigest, 0, sizeof(szDigest) );

memset( szOutput, 0, sizeof(szOutput) );

EVP_DigestInit( &sttCtx, m_psttMd );

EVP_DigestUpdate( &sttCtx, strKey.c_str(), strKey.length() );

EVP_DigestUpdate( &sttCtx, "258EAFA5-E914-47DA-95CA-C5AB0DC85B11", 36 );

EVP_DigestFinal( &sttCtx, szDigest, &iDigestLen );

Base64Encode( (char *)szDigest, iDigestLen, szOutput, sizeof(szOutput) );

pclsSend->AddHeader( "Sec-WebSocket-Accept", szOutput );

return true;

}