await connection.connect() results in a segfault

• I’ve searched for previous similar issues and didn’t find any solution

Known Issue

• I’m using ATS data type endpoint: the endpoint should look like <prefix>-ats.iot.<region>.amazonaws.com

Describe the bug

await connection.connect(); results in a segfault:

Signal received: -1050417728, errno: 32521
################################################################################
Resolved stacktrace:
################################################################################
0x00007f09c17c40cb: ?? ??:0
0x00000000000b1b03: s_print_stack_trace at module.c:?
0x00000000000153c0: __restore_rt at ??:?
0x00007f09c17a64e1: ?? ??:0
0x00007f09c176e5b4: ?? ??:0
0x00000000001134ac: s_drive_negotiation at s2n_tls_channel_handler.c:?
0x0000000000106b98: s_on_client_channel_on_setup_completed at channel_bootstrap.c:?
0x0000000000105b42: s_on_channel_setup_complete at channel.c:?
0x000000000017b6ee: s_run_all at task_scheduler.c:?
0x000000000010cf88: s_main_loop at epoll_event_loop.c:?
0x00000000001794cb: thread_fn at thread.c:?
0x0000000000009609: start_thread at ??:?
0x00007f09c4536293: ?? ??:0
################################################################################
Raw stacktrace:
################################################################################
/home/ubuntu/persist/code/toolshed/connection-hub-lite/node_modules/aws-crt/dist/bin/linux-x64/aws-crt-nodejs.node(aws_backtrace_print+0x4b) [0x7f09c17c40cb]
/home/ubuntu/persist/code/toolshed/connection-hub-lite/node_modules/aws-crt/dist/bin/linux-x64/aws-crt-nodejs.node(+0xb1b03) [0x7f09c16fcb03]
/lib/x86_64-linux-gnu/libpthread.so.0(+0x153c0) [0x7f09c461b3c0]
/home/ubuntu/persist/code/toolshed/connection-hub-lite/node_modules/aws-crt/dist/bin/linux-x64/aws-crt-nodejs.node(s2n_client_hello_send+0x1e1) [0x7f09c17a64e1]
/home/ubuntu/persist/code/toolshed/connection-hub-lite/node_modules/aws-crt/dist/bin/linux-x64/aws-crt-nodejs.node(s2n_negotiate+0x334) [0x7f09c176e5b4]
/home/ubuntu/persist/code/toolshed/connection-hub-lite/node_modules/aws-crt/dist/bin/linux-x64/aws-crt-nodejs.node(+0x1134ac) [0x7f09c175e4ac]
/home/ubuntu/persist/code/toolshed/connection-hub-lite/node_modules/aws-crt/dist/bin/linux-x64/aws-crt-nodejs.node(+0x106b98) [0x7f09c1751b98]
/home/ubuntu/persist/code/toolshed/connection-hub-lite/node_modules/aws-crt/dist/bin/linux-x64/aws-crt-nodejs.node(+0x105b42) [0x7f09c1750b42]
/home/ubuntu/persist/code/toolshed/connection-hub-lite/node_modules/aws-crt/dist/bin/linux-x64/aws-crt-nodejs.node(+0x17b6ee) [0x7f09c17c66ee]
/home/ubuntu/persist/code/toolshed/connection-hub-lite/node_modules/aws-crt/dist/bin/linux-x64/aws-crt-nodejs.node(+0x10cf88) [0x7f09c1757f88]
/home/ubuntu/persist/code/toolshed/connection-hub-lite/node_modules/aws-crt/dist/bin/linux-x64/aws-crt-nodejs.node(+0x1794cb) [0x7f09c17c44cb]
/lib/x86_64-linux-gnu/libpthread.so.0(+0x9609) [0x7f09c460f609]
/lib/x86_64-linux-gnu/libc.so.6(clone+0x43) [0x7f09c4536293]

SDK version number “aws-crt”: “^1.3.0”, “aws-iot-device-sdk-v2”: “^1.3.1”,

Platform/OS/Hardware/Device Ubuntu 20.04 LTS

To Reproduce (observed behavior)

I’ve adapted the pub/sub example. I’ve verified the option value by using Mqtt.fx to successfully connect with the same configuration.

  const configBuilder = iot.AwsIotMqttConnectionConfigBuilder.new_mtls_builder_from_path(
    options.cert, options.key,
  );
  configBuilder.with_certificate_authority_from_path(undefined, options.ca_file);

  configBuilder.with_clean_session(false);
  configBuilder.with_client_id(options.client_id);
  configBuilder.with_endpoint(options.endpoint);

  const config = configBuilder.build();
  const client = new mqtt.MqttClient(clientBootstrap);
  const connection = client.new_connection(config);

  await connection.connect();

Steps to reproduce the behavior (please share code)

Expected behavior

I’d expect it to connect, but it doesn’t. And the error doesn’t seem to indicate what is causing the segfault to me.

Logs/output

(See report)

[thomasmichaelwallace]

Sure @EyalSi - you can use mqtt for the connection to IoT Core.

/* eslint-disable no-console */
const mqtt = require('mqtt');
const fs = require('fs');

const options = {
  key: fs.readFileSync('path-to-key-file'),
  cert: fs.readFileSync('path-to-cert-file'),
  ca: fs.readFileSync('path-to-ca-file'),
};

async function main() {
  const client = mqtt.connect('mqtt://your-iot-account-ats.iot.region.amazonaws.com', options);

  client.on('connect', () => {
    client.subscribe(['a/topic/here', 'another/topic/+/here'], (err) => {
      if (!err) {
        console.log('connected');
      } else {
        console.error('failed to connect', err);
      }
    });
  });

  client.on('message', async (topic, message) => {
    const event = { topic, message: JSON.parse(message.toString()) };
    console.log(JSON.stringify(event));
  });

  // if/when you need to close:
  // client.end();
}
main()

(You can use the aws-sdk-js IoT namespace, https://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/Iot.html, to do all the service stuff like creating rules, retc.)

[thomasmichaelwallace]

@bharring - probably worth noting that this issue is quite old now and wasn’t ever noticed by the maintainers.

You might have better luck opening a new issue (then again, you might not, who knows with AWS’ open source projects!).

I will say, though, that this SDK doesn’t really add that much, given the amount of confusion and debugging/deployment-difficulty it introduces by using C bindings.

Alternatively, both the node mqtt and aws-sdk libraries are well maintained, are in native javascript, and have larger communities. I suspect you will get more mileage out of using the approach I outlined in my workaround.