Prevote nil if proposal is not timely (#7415)

* Prevote nil if not timely

* William's suggestion to get the proposal from the proposer instead of
generating it.

* Don't check rhs for genesis block

* Update IsTimely to match the specification

* Fix proposal tests

* Add more timely tests and check votes

* Mark proposal invalid in SetProposal, fix in the future test

* save proposal time on roundstate

* received -> receive

* always reset proposal time

* Add IsTimely test for genesis proposal

* Check timely before ValidateBlock

* Review comments from Daniel

Co-authored-by: William Banfield <wbanfield@gmail.com>

types/params.go

@@ -129,8 +129,8 @@ func DefaultTimingParams() TimingParams {
 	// TODO(@wbanfield): Determine experimental values for these defaults
 	// https://github.com/tendermint/tendermint/issues/7202
 	return TimingParams{
-		Precision:    1 * time.Nanosecond,
-		MessageDelay: 1 * time.Nanosecond,
+		Precision:    10 * time.Millisecond,
+		MessageDelay: 500 * time.Millisecond,
 	}
 }
 

types/proposal.go

@@ -84,18 +84,24 @@ func (p *Proposal) ValidateBasic() error {
 // configured Precision and MsgDelay parameters.
 // Specifically, a proposed block timestamp is considered timely if it is satisfies the following inequalities:
 //
-// proposedBlockTime > validatorLocaltime - Precision && proposedBlockTime < validatorLocalTime + Precision + MsgDelay.
+// localtime >= proposedBlockTime - Precision
+// localtime <= proposedBlockTime + MsgDelay + Precision
 //
+// Note: If the proposal is for the `initialHeight` the second inequality is not checked. This is because
+// the timestamp in this case is set to the preconfigured genesis time.
 // For more information on the meaning of 'timely', see the proposer-based timestamp specification:
 // https://github.com/tendermint/spec/tree/master/spec/consensus/proposer-based-timestamp
-func (p *Proposal) IsTimely(clock tmtime.Source, tp TimingParams) bool {
-	lt := clock.Now()
-	lhs := lt.Add(-tp.Precision)
-	rhs := lt.Add(tp.Precision).Add(tp.MessageDelay)
-	if lhs.Before(p.Timestamp) && rhs.After(p.Timestamp) {
-		return true
+func (p *Proposal) IsTimely(recvTime time.Time, tp TimingParams, initialHeight int64) bool {
+	// lhs is `proposedBlockTime - Precision` in the first inequality
+	lhs := p.Timestamp.Add(-tp.Precision)
+	// rhs is `proposedBlockTime + MsgDelay + Precision` in the second inequality
+	rhs := p.Timestamp.Add(tp.MessageDelay).Add(tp.Precision)
+
+	if recvTime.Before(lhs) || (p.Height != initialHeight && recvTime.After(rhs)) {
+		return false
 	}
-	return false
+
+	return true
 }
 
 // String returns a string representation of the Proposal.

types/proposal_test.go

@@ -14,7 +14,6 @@ import (
 	"github.com/tendermint/tendermint/internal/libs/protoio"
 	tmrand "github.com/tendermint/tendermint/libs/rand"
 	tmtime "github.com/tendermint/tendermint/libs/time"
-	tmtimemocks "github.com/tendermint/tendermint/libs/time/mocks"
 	tmproto "github.com/tendermint/tendermint/proto/tendermint/types"
 )
 
@@ -217,47 +216,84 @@ func TestIsTimely(t *testing.T) {
 	genesisTime, err := time.Parse(time.RFC3339, "2019-03-13T23:00:00Z")
 	require.NoError(t, err)
 	testCases := []struct {
-		name         string
-		proposalTime time.Time
-		localTime    time.Time
-		precision    time.Duration
-		msgDelay     time.Duration
-		expectTimely bool
+		name           string
+		genesisHeight  int64
+		proposalHeight int64
+		proposalTime   time.Time
+		recvTime       time.Time
+		precision      time.Duration
+		msgDelay       time.Duration
+		expectTimely   bool
 	}{
+		// proposalTime - precision <= localTime <= proposalTime + msgDelay + precision
 		{
 			// Checking that the following inequality evaluates to true:
-			// 1 - 2 < 0 < 1 + 2 + 1
-			name:         "basic timely",
-			proposalTime: genesisTime,
-			localTime:    genesisTime.Add(1 * time.Nanosecond),
-			precision:    time.Nanosecond * 2,
-			msgDelay:     time.Nanosecond,
-			expectTimely: true,
+			// 0 - 2 <= 1 <= 0 + 1 + 2
+			name:           "basic timely",
+			genesisHeight:  1,
+			proposalHeight: 2,
+			proposalTime:   genesisTime,
+			recvTime:       genesisTime.Add(1 * time.Nanosecond),
+			precision:      time.Nanosecond * 2,
+			msgDelay:       time.Nanosecond,
+			expectTimely:   true,
 		},
 		{
 			// Checking that the following inequality evaluates to false:
-			// 3 - 2 < 0 < 3 + 2 + 1
-			name:         "local time too large",
-			proposalTime: genesisTime,
-			localTime:    genesisTime.Add(3 * time.Nanosecond),
-			precision:    time.Nanosecond * 2,
-			msgDelay:     time.Nanosecond,
-			expectTimely: false,
+			// 0 - 2 <= 4 <= 0 + 1 + 2
+			name:           "local time too large",
+			genesisHeight:  1,
+			proposalHeight: 2,
+			proposalTime:   genesisTime,
+			recvTime:       genesisTime.Add(4 * time.Nanosecond),
+			precision:      time.Nanosecond * 2,
+			msgDelay:       time.Nanosecond,
+			expectTimely:   false,
 		},
 		{
 			// Checking that the following inequality evaluates to false:
-			// 0 - 2 < 2 < 2 + 1
-			name:         "proposal time too large",
-			proposalTime: genesisTime.Add(4 * time.Nanosecond),
-			localTime:    genesisTime,
-			precision:    time.Nanosecond * 2,
-			msgDelay:     time.Nanosecond,
-			expectTimely: false,
+			// 4 - 2 <= 0 <= 4 + 2 + 1
+			name:           "proposal time too large",
+			genesisHeight:  1,
+			proposalHeight: 2,
+			proposalTime:   genesisTime.Add(4 * time.Nanosecond),
+			recvTime:       genesisTime,
+			precision:      time.Nanosecond * 2,
+			msgDelay:       time.Nanosecond,
+			expectTimely:   false,
+		},
+		{
+			// Checking that the following inequality evaluates to true:
+			// 0 - 2 <= 4
+			// and the following check is skipped
+			// 4 <= 0 + 1 + 2
+			name:           "local time too large but proposal is for genesis",
+			genesisHeight:  1,
+			proposalHeight: 1,
+			proposalTime:   genesisTime,
+			recvTime:       genesisTime.Add(4 * time.Nanosecond),
+			precision:      time.Nanosecond * 2,
+			msgDelay:       time.Nanosecond,
+			expectTimely:   true,
+		},
+		{
+			// Checking that the following inequality evaluates to false:
+			// 4 - 2 <= 0
+			name:           "proposal time too large for genesis block proposal",
+			genesisHeight:  1,
+			proposalHeight: 1,
+			proposalTime:   genesisTime.Add(4 * time.Nanosecond),
+			recvTime:       genesisTime,
+			precision:      time.Nanosecond * 2,
+			msgDelay:       time.Nanosecond,
+			expectTimely:   false,
 		},
 	}
+
 	for _, testCase := range testCases {
 		t.Run(testCase.name, func(t *testing.T) {
 			p := Proposal{
+				Height:    testCase.proposalHeight,
 				Timestamp: testCase.proposalTime,
 			}
 
@@ -266,10 +302,7 @@ func TestIsTimely(t *testing.T) {
 				MessageDelay: testCase.msgDelay,
 			}
 
-			mockSource := new(tmtimemocks.Source)
-			mockSource.On("Now").Return(testCase.localTime)
-
-			ti := p.IsTimely(mockSource, tp)
+			ti := p.IsTimely(testCase.recvTime, tp, testCase.genesisHeight)
 			assert.Equal(t, testCase.expectTimely, ti)
 		})
 	}