libwebsocket server with openSSL not accepting connection

Question

I have written web socket server with the help of (libwebsocket library )which accepts web socket client connection for non SSL. Now I wanted it to accept SSL connection so I have generated the self signed certificate and key, while creating web socket context I have given the key and certificate path and option LWS_SERVER_OPTION_DO_SSL_GLOBAL_INIT as well. But while making https connection using wss://ip:7681 from I am getting connection request callback i.e LWS_CALLBACK_SERVER_NEW_CLIENT_INSTANTIATED and after that LWS_CALLBACK_WSI_DESTROY and in browser getting console error about not able to connect.

  Firefox can’t establish a connection to the server at wss://192.168.4.254:7681/.

Please check the following server side code used for creating openSSL based web socket server.

struct lws_protocols WebSocketCommon::protocols[ 2 ] = { {"wss", WebSocketCommon::callback, 0,    0 },{ NULL, NULL, 0, 0 } };

int callback ( struct lws *wsi, enum lws_callback_reasons reason, void *user, void *in, size_t len ) {
   switch ( reason ) {

    case LWS_CALLBACK_SERVER_NEW_CLIENT_INSTANTIATED:
    {
         //code 
         break;      
    }
    case LWS_CALLBACK_WSI_DESTROY: 
    {
         //code 
         break;
    }  
    case LWS_CALLBACK_OPENSSL_LOAD_EXTRA_SERVER_VERIFY_CERTS: {
        Log::d( m_r_logger, TAG, "LWS_CALLBACK_OPENSSL_LOAD_EXTRA_SERVER_VERIFY_CERTS\n");
        SSL_CTX_load_verify_locations( (SSL_CTX*) user, NULL, getenv(SSL_CERT_FILE_PATH) );
        break;
    }
        default: {
            break;
    }
}

return lws_callback_http_dummy(wsi, reason, user, in, len);
} 

void createContext (bool useSSL) {
    struct lws_context_creation_info info;
    memset( &info, 0, sizeof(struct lws_context_creation_info) );

    info.port = 7681;
    info.uid = -1;
    info.gid = -1;
    info.protocols = protocols;
    info.mounts = &mount;

    info.extensions = exts;
    info.timeout_secs = 5;
    info.ip_limit_ah = 24; /* for testing */
    info.ip_limit_wsi = 400; /* for testing */

    // Following options for openSSL certificate
    if(useSSL){
        info.options = LWS_SERVER_OPTION_DO_SSL_GLOBAL_INIT | LWS_SERVER_OPTION_ALLOW_NON_SSL_ON_SSL_PORT | LWS_SERVER_OPTION_DISABLE_IPV6 | LWS_SERVER_OPTION_PEER_CERT_NOT_REQUIRED | LWS_SERVER_OPTION_IGNORE_MISSING_CERT;
        info.ssl_cert_filepath = SSL_CERT_FILE_PATH;
        info.ssl_private_key_filepath = SSL_PRIVATE_KEY_PATH;
    }
    fContext = lws_create_context( &info );

    }

I am getting following logs while creating web socket context and accepting wss connection.

WebSocket.cpp:638...... :createContext ( ) - begin
WebSocket.cpp:640...... : createContext - fReferenceCount = 0
WebSocket.cpp:324...... : Creating Vhost 'default' port 7681, 1 protocols, IPv6 off
WebSocket.cpp:324...... :  Using SSL mode
WebSocket.cpp:324...... :  SSL ECDH curve 'prime256v1'
WebSocket.cpp:612...... : LWS_CALLBACK_OPENSSL_LOAD_EXTRA_SERVER_VERIFY_CERTS
WebSocket.cpp:324...... : lws_tls_client_create_vhost_context: doing cert filepath /etc/nginx  /ssl/mycert.crt
WebSocket.cpp:324...... : Loaded client cert /etc/nginx/ssl/mycert.crt
WebSocket.cpp:324...... : lws_tls_client_create_vhost_context: doing private key filepath
WebSocket.cpp:324...... : Loaded client cert private key /etc/nginx/ssl/mykey.key
WebSocket.cpp:324...... : created client ssl context for default
WebSocket.cpp:684...... : lws_create_context SUCCEEDED
WebSocket.cpp:759...... : start  Starting Service Thread.
WebSocket.cpp:705...... : createContext - fReferenceCount = 1 
WebSocket.cpp:706...... : createContext - end

Following is library versions I am using.

libwebsocket.so 13
OpenSSL 1.0.2o  27 Mar 2018

Please let me know what is going wrong ?

Better to debug using openssl as a client and connect to your server — Abhishek Chandel, Nov 05 '19 at 14:26

score 0 · Answer 1 · answered Nov 05 '19 at 14:23

The problem is possibly not related to libwebsockets, but rather to do with Firefox being fussy about allowing connections to WSS that have a self signed certificate. Try to connect to your server from some other program, e.g., a simple python program.

Firefox disconnects websockets connection for a self signed certificate

libwebsocket server with openSSL not accepting connection

1 Answers1