Support verifyAdjacent

[danwt]

Hi

It seems that the relayer cannot handle val set changes between H and H+1 of more than trustLevel voting power, because it does not properly pass adjacent headers to be routed through verifyAdjacent. As far as I can tell, this is not supported.

This is causing problems for our use case where we have validator sets of size 1 (100% voting power change, 1/1 trust level). I would be keen to hear more about this ASAP and work to get it solved

Thanks

[danwt]

In fact, from looking v2.5.2 there doesn't seem to be any support for updating with concern about voting power changes. The relayer just always tries to update the light client with the latest header of the counterparty, using the last trusted height.

[danwt]

Side note:

What is this code doing?

relayer/relayer/processor/path_processor_internal.go

Lines 702 to 710 in 3b9ec00

	if ibcHeaderCurrent, ok := dst.ibcHeaderCache[src.clientState.ConsensusHeight.RevisionHeight]; ok &&
	dst.clientTrustedState.IBCHeader != nil &&
	bytes.Equal(dst.clientTrustedState.IBCHeader.NextValidatorsHash(), ibcHeaderCurrent.NextValidatorsHash()) {
	src.clientTrustedState = provider.ClientTrustedState{
	ClientState: src.clientState,
	IBCHeader: ibcHeaderCurrent,
	}
	return
	}

Seems it's wrong, it checks bytes.Equal(dst.clientTrustedState.IBCHeader.NextValidatorsHash(), ibcHeaderCurrent.NextValidatorsHash()) on 704 which doesn't make sense