listen address: 0.0.0.0:2022 doesn't listen on tcp4, only tpc6

[erjoalgo]

Not sure what has changed but by default my sshesame instance is only listening on ipv6 despite being configured with a listen address of 0.0.0.0:2022:

# using listen_address: 127.0.0.1:2022
Sep 24 23:42:53 my-hostname sshesame[1950846]: INFO 2023/09/24 23:42:53 Listening on 127.0.0.1:2022
Sep 24 23:43:26 my-hostname systemd[1]: Stopping sshesame.service - sshesame...
Sep 24 23:43:26 my-hostname systemd[1]: sshesame.service: Deactivated successfully.
Sep 24 23:43:26 my-hostname systemd[1]: Stopped sshesame.service - sshesame.
Sep 24 23:43:26 my-hostname systemd[1]: Started sshesame.service - sshesame.
Sep 24 23:43:26 my-hostname sshesame[1951085]: INFO 2023/09/24 23:43:26 No host keys configured, using keys at "/home/USER/.local/share/sshesame"


# using listen_address: 0.0.0.0:2022
Sep 24 23:43:26 my-hostname sshesame[1951085]: INFO 2023/09/24 23:43:26 Listening on [::]:2022

go version
go version go1.20.7 linux/amd64

[email protected]/

[erjoalgo]

I modified github.com/jaksi/[email protected]/conn.go to use tcp4 instead of tcp and now the service is listening on the intended address, 0.0.0.0:2022:

l, err := net.Listen("tcp4", address)

Not sure if there has been a change in go to default to ipv6, the go contributor's comment in the bug below appears to suggest that using net: Listen("tcp", "0.0.0.0:1234") would bind to both ipv4 and ipv6 addresses, but on my system nothing was listening on ipv4:

golang/go#48723 (comment)