CC3220SF-LAUNCHXL: Enabling ALPN extension for MQTT connection in AWS TI code

Hi Kishore,

If you are using the text ALPN, you should use the SL_SO_SECURE_ALPN_GENERAL option.

Br,

Kobi

Hi Kobi,

As suggested I have added this piece of code to try out

#define SL_SO_SECURE_ALPN_GENERAL                             (44) /* set ALPN protocol name by string - only one protocol name can be set */

sTIRetCode = sl_SetSockOpt( pxSocketContext->sSocketDescriptor, SL_SOL_SOCKET, SL_SO_SECURE_ALPN_GENERAL, "x-amzn-mqtt-ca", strlen( "x-amzn-mqtt-ca" ) );

But sl_SetSockOpt returns -92 in this case which is "Protocol not available".

Regards,

Kishore.

Hi,

What SDK and SP are you using.

I've just tested the command (with your setting) and got successful return code.

If i understand correctly, the error is when you set the option and not when you are connecting.

Br,

Kobi

Hi,

I am using the demo code base downloaded from AWS for CC3220SF LAUNCHXL.

Yes, the error code -92 is returned while setting the socket option and eventually it fails in making MQTT connection too.

Regards,

Kishore.

Hi Kobe,

Hope you are doing well. It's been a long time since my last query. Can I have any update on this?

Regards,

Kishore.

Please show your entire socket handling code (from socket creation to getting the -92). As i said before, I added the SL_SO_SECURE_ALPN_GENERAL successfully, so need to understand the source of your issue.

Are you using the latest SDK and SP? if not, please update.

Br,

Kobi

Hi,

Sorry for a late follow up.

I have added below piece of code in MQTT demo code downloaded from AWS  in the function SOCKETS_SetSocketOpt which is in the file iot_secure_sockets.c by changing clientcredentialMQTT_BROKER_PORT to 443 in aws_clientcredential.h. I have just added a case SOCKETS_SO_ALPN_PROTOCOLS which is previously not present in the code.

#define socketsAWS_IOT_ALPN_MQTT    "x-amzn-mqtt-ca"

switch( lOptionName )
{
case SOCKETS_SO_ALPN_PROTOCOLS:
{

const char * ppcALPNProtos[] = { socketsAWS_IOT_ALPN_MQTT };

sTIRetCode = sl_SetSockOpt( pxSocketContext->sSocketDescriptor,
SL_SOL_SOCKET,
SL_SO_SECURE_ALPN_GENERAL,
ppcALPNProtos,
sizeof( ppcALPNProtos ) );

/* If the above sl_SetSockOpt succeeded, return success to the user. */
if( sTIRetCode >= 0 )
{
lRetCode = SOCKETS_ERROR_NONE;
}
else
{
/* See vendors/ti/SimpleLink_CC32xx/v2_10_00_04/source/ti/drivers/net/wifi/errors.h */
SOCKETS_PRINT( ( "ERROR: %d SockOpt ALPN failed.\r\n", sTIRetCode ) );
}
}

break;

Can I also know which example and SDK are you using?

Regards,

Kishore.