// Decides on the next proposal and sets them onto cs.Proposal*
func (cs *ConsensusState) decideProposal(height int, round int) {
var block *types.Block
var blockParts *types.PartSet
// Decide on block
if cs.LockedBlock != nil {
// If we're locked onto a block, just choose that.
block, blockParts = cs.LockedBlock, cs.LockedBlockParts
} else {
// Create a new proposal block from state/txs from the mempool.
block, blockParts = cs.createProposalBlock()
}
// Make proposal
proposal := types.NewProposal(height, round, blockParts.Header(), cs.Votes.POLRound())
err := cs.privValidator.SignProposal(cs.state.ChainID, proposal)
if err == nil {
log.Notice("Signed and set proposal", "height", height, "round", round, "proposal", proposal)
log.Debug(Fmt("Signed and set proposal block: %v", block))
// Set fields
cs.Proposal = proposal
cs.ProposalBlock = block
cs.ProposalBlockParts = blockParts
} else {
log.Warn("EnterPropose: Error signing proposal", "height", height, "round", round, "error", err)
}
}
func TestBadProposal(t *testing.T) {
css, privVals := simpleConsensusState(2)
cs1, cs2 := css[0], css[1]
cs1.newStepCh = make(chan *RoundState) // so it blocks
timeoutChan := make(chan struct{})
evsw := events.NewEventSwitch()
evsw.OnStart()
evsw.AddListenerForEvent("tester", types.EventStringTimeoutPropose(), func(data types.EventData) {
timeoutChan <- struct{}{}
})
evsw.AddListenerForEvent("tester", types.EventStringTimeoutWait(), func(data types.EventData) {
timeoutChan <- struct{}{}
})
cs1.SetFireable(evsw)
// make the second validator the proposer
propBlock := changeProposer(t, cs1, cs2)
// make the block bad by tampering with statehash
stateHash := propBlock.StateHash
stateHash[0] = byte((stateHash[0] + 1) % 255)
propBlock.StateHash = stateHash
propBlockParts := propBlock.MakePartSet()
proposal := types.NewProposal(cs2.Height, cs2.Round, propBlockParts.Header(), cs2.Votes.POLRound())
if err := cs2.privValidator.SignProposal(cs2.state.ChainID, proposal); err != nil {
t.Fatal("failed to sign bad proposal", err)
}
// start round
cs1.EnterNewRound(cs1.Height, 0, false)
// now we're on a new round and not the proposer
<-cs1.NewStepCh()
// so set the proposal block (and fix voting power)
cs1.mtx.Lock()
cs1.Proposal, cs1.ProposalBlock, cs1.ProposalBlockParts = proposal, propBlock, propBlockParts
fixVotingPower(t, cs1, privVals[1].Address)
cs1.mtx.Unlock()
// and wait for timeout
<-timeoutChan
// go to prevote, prevote for nil (proposal is bad)
<-cs1.NewStepCh()
validatePrevote(t, cs1, 0, privVals[0], nil)
// add bad prevote from cs2. we should precommit nil
signAddVoteToFrom(types.VoteTypePrevote, cs1, cs2, propBlock.Hash(), propBlock.MakePartSet().Header())
_, _, _ = <-cs1.NewStepCh(), <-timeoutChan, <-cs1.NewStepCh()
validatePrecommit(t, cs1, 0, 0, privVals[0], nil, nil)
signAddVoteToFrom(types.VoteTypePrecommit, cs1, cs2, propBlock.Hash(), propBlock.MakePartSet().Header())
}
