Loopback connection is considered insecure

[htdvisser]

Summary

The loopback connection is not considered secure by gRPC, resulting in errors when sending credentials on it (transport: cannot send secure credentials on an insecure connection).

Steps to Reproduce

1. Start the stack
2. Connect an authenticated gateway to the GS

What do you see now?

Reported by Matthew Dean on Slack:

stack_1      |   WARN Finished unary call                      duration=48.909µs error=rpc error: code = Unauthenticated desc = transport: cannot send secure credentials on an insecure connection grpc_code=Unauthenticated grpc_method=Get grpc_service=ttn.lorawan.v3.GatewayRegistry namespace=grpc
stack_1      |   WARN Failed to setup connection               error=error:unknown:unknown (transport: cannot send secure credentials on an insecure connection) namespace=gatewayserver/io/mqtt remote_addr=X.X.X.X:35175

What do you want to see instead?

It shouldn't complain about this

Environment

v3.0.3

How do you propose to implement this?

• either we make the loopback connection use transport security, or
• we tell gRPC to consider the loopback connection secure

Can you do this yourself and submit a Pull Request?

Sure.

Until this is resolved the recommended workaround is using the grpc.allow-insecure-for-credentials flag.

[htdvisser]

With #739 and #755 merged this issue should now be resolved (in master, or the next patch release)