network: disable libp2p message signing

[nkryuchkov]

Issue Addressed

SSV node rejects messages from Anchor on libp2p level with the unexpected signature error:

{"level":"\u001b[35mDEBUG\u001b[0m","time":"2025-03-20T17:49:22.143585Z","name":"P2PNetwork.PubsubTrace","msg":"pubsub event","selfPeer":"16Uiu2HAkvNzRHEEwS8He6iF7esFCBN4nPWsswjVJRPByPjH4sDdh","type":"REJECT_MESSAGE","receivedFrom":"16Uiu2HAmPamdZidzgF47ZqCTCYQ6Lp6nxHtRs64ccFuu2VAChdiZ","msgID":"baea56cec621b52300000000","topic":"ssv.v2.84","reason":"unexpected signature"}

Proposed Changes

Disable message signing on the libp2p level by setting MessageAuthenticity to Anonymous

Additional Info

SSV node disables signing on the libp2p level because its messages have a payload with signature: https://github.com/ssvlabs/ssv/blob/v2.2.0/network/topics/pubsub.go#L138

This allows choosing a signing scheme that's appropriate in terms of resource consumption.

[diegomrsantos]

@nkryuchkov Thank you for opening this PR. Should we also change the validation to this https://docs.rs/libp2p-gossipsub/latest/libp2p_gossipsub/enum.ValidationMode.html#variant.Anonymous?

[Copilot]

Pull Request Overview

This PR disables libp2p message signing to address unexpected signature errors by configuring the gossipsub behaviour to use anonymous message authenticity rather than signing messages.

• Replace MessageAuthenticity::Signed with MessageAuthenticity::Anonymous
• Update gossipsub configuration in the network component

Comments suppressed due to low confidence (1)

anchor/network/src/network.rs:364

• [nitpick] Since 'local_keypair' is no longer used with the new anonymous configuration, consider removing the cloning or the variable itself if it isn’t required elsewhere.

-        gossipsub::Behaviour::new(MessageAuthenticity::Signed(local_keypair.clone()), config)

[nkryuchkov]

@nkryuchkov Thank you for opening this PR. Should we also change the validation to this https://docs.rs/libp2p-gossipsub/latest/libp2p_gossipsub/enum.ValidationMode.html#variant.Anonymous?

I agree. Although Permissive should work too, Anonymous would match the SSV node behavior. Changed

[diegomrsantos]

LGTM, thanks again!

[jking-aus]

lgtm thanks