From d8e422c9ffc13ecc71e0a1387e6299ab9385abc6 Mon Sep 17 00:00:00 2001
From: Kishan Sagathiya <kishansagathiya@gmail.com>
Date: Fri, 10 Jun 2022 20:23:44 +0530
Subject: [PATCH] Remove checks for equivocatory blocks

---
 lib/babe/errors.go                  |  3 --
 lib/babe/verify.go                  | 29 ------------------
 lib/babe/verify_integration_test.go | 47 -----------------------------
 lib/babe/verify_test.go             | 39 ------------------------
 4 files changed, 118 deletions(-)

diff --git a/lib/babe/errors.go b/lib/babe/errors.go
index 527a0a8915..521007187b 100644
--- a/lib/babe/errors.go
+++ b/lib/babe/errors.go
@@ -33,9 +33,6 @@ var (
 	// ErrBadSignature is returned when a seal is invalid
 	ErrBadSignature = errors.New("could not verify signature")
 
-	// ErrProducerEquivocated is returned when a block producer has produced conflicting blocks
-	ErrProducerEquivocated = errors.New("block producer equivocated")
-
 	// ErrNotAuthorized is returned when the node is not authorized to produce a block
 	ErrNotAuthorized = errors.New("not authorized to produce block")
 
diff --git a/lib/babe/verify.go b/lib/babe/verify.go
index add58392a4..d4b01d26b0 100644
--- a/lib/babe/verify.go
+++ b/lib/babe/verify.go
@@ -340,35 +340,6 @@ func (b *verifier) verifyAuthorshipRight(header *types.Header) error {
 		return ErrBadSignature
 	}
 
-	// check if the producer has equivocated, ie. have they produced a conflicting block?
-	hashes := b.blockState.GetAllBlocksAtDepth(header.ParentHash)
-
-	for _, hash := range hashes {
-		currentHeader, err := b.blockState.GetHeader(hash)
-		if err != nil {
-			continue
-		}
-
-		currentBlockProducerIndex, err := getAuthorityIndex(currentHeader)
-		if err != nil {
-			continue
-		}
-
-		var existingBlockProducerIndex uint32
-		switch d := babePreDigest.(type) {
-		case types.BabePrimaryPreDigest:
-			existingBlockProducerIndex = d.AuthorityIndex
-		case types.BabeSecondaryVRFPreDigest:
-			existingBlockProducerIndex = d.AuthorityIndex
-		case types.BabeSecondaryPlainPreDigest:
-			existingBlockProducerIndex = d.AuthorityIndex
-		}
-
-		if currentBlockProducerIndex == existingBlockProducerIndex && hash != header.Hash() {
-			return ErrProducerEquivocated
-		}
-	}
-
 	return nil
 }
 
diff --git a/lib/babe/verify_integration_test.go b/lib/babe/verify_integration_test.go
index 48cdd864da..5e298ecfcc 100644
--- a/lib/babe/verify_integration_test.go
+++ b/lib/babe/verify_integration_test.go
@@ -386,53 +386,6 @@ func TestVerifyAuthorshipRight(t *testing.T) {
 	require.NoError(t, err)
 }
 
-func TestVerifyAuthorshipRight_Equivocation(t *testing.T) {
-	kp, err := sr25519.GenerateKeypair()
-	require.NoError(t, err)
-
-	cfg := &ServiceConfig{
-		Keypair: kp,
-	}
-
-	babeService := createTestService(t, cfg)
-	epochData, err := babeService.initiateEpoch(testEpochIndex)
-	require.NoError(t, err)
-
-	epochData.threshold = maxThreshold
-	epochData.authorities = []types.Authority{
-		{
-			Key: kp.Public().(*sr25519.PublicKey),
-		},
-	}
-
-	// create and add first block
-	block := createTestBlock(t, babeService, genesisHeader, [][]byte{}, 1, testEpochIndex, epochData)
-	block.Header.Hash()
-
-	err = babeService.blockState.AddBlock(block)
-	require.NoError(t, err)
-
-	verifier, err := newVerifier(babeService.blockState, testEpochIndex, &verifierInfo{
-		authorities: epochData.authorities,
-		threshold:   epochData.threshold,
-		randomness:  epochData.randomness,
-	})
-	require.NoError(t, err)
-
-	err = verifier.verifyAuthorshipRight(&block.Header)
-	require.NoError(t, err)
-
-	// create new block
-	block2 := createTestBlock(t, babeService, genesisHeader, [][]byte{}, 1, testEpochIndex, epochData)
-	block2.Header.Hash()
-
-	err = babeService.blockState.AddBlock(block2)
-	require.NoError(t, err)
-
-	err = verifier.verifyAuthorshipRight(&block2.Header)
-	require.Equal(t, ErrProducerEquivocated, err)
-}
-
 func TestVerifyForkBlocksWithRespectiveEpochData(t *testing.T) {
 	/*
 	* Setup the services: StateService, DigestHandler, EpochState
diff --git a/lib/babe/verify_test.go b/lib/babe/verify_test.go
index f6c106ca7c..739584f03f 100644
--- a/lib/babe/verify_test.go
+++ b/lib/babe/verify_test.go
@@ -612,27 +612,6 @@ func Test_verifier_verifyAuthorshipRight(t *testing.T) {
 	//// Case 8: Get header error
 	babeVerifier6 := newTestVerifier(t, kp, mockBlockStateErr, scale.MaxUint128, false)
 
-	// Case 9: Equivocate case primary
-	babeVerifier7 := newTestVerifier(t, kp, mockBlockStateEquiv1, scale.MaxUint128, false)
-
-	// Case 10: Equivocate case secondary plain
-	babeSecPlainPrd2, err := testBabeSecondaryPlainPreDigest.ToPreRuntimeDigest()
-	assert.NoError(t, err)
-	header8 := newTestHeader(t, *babeSecPlainPrd2)
-
-	hash2 := encodeAndHashHeader(t, header8)
-	signAndAddSeal(t, kp, header8, hash2[:])
-	babeVerifier8 := newTestVerifier(t, kp, mockBlockStateEquiv2, scale.MaxUint128, true)
-
-	// Case 11: equivocation case secondary VRF
-	encVrfDigest := newEncodedBabeDigest(t, testBabeSecondaryVRFPreDigest)
-	assert.NoError(t, err)
-	header9 := newTestHeader(t, *types.NewBABEPreRuntimeDigest(encVrfDigest))
-
-	hash3 := encodeAndHashHeader(t, header9)
-	signAndAddSeal(t, kp, header9, hash3[:])
-	babeVerifier9 := newTestVerifier(t, kp, mockBlockStateEquiv3, scale.MaxUint128, true)
-
 	tests := []struct {
 		name     string
 		verifier verifier
@@ -697,24 +676,6 @@ func Test_verifier_verifyAuthorshipRight(t *testing.T) {
 			verifier: *babeVerifier6,
 			header:   header7,
 		},
-		{
-			name:     "equivocate - primary",
-			verifier: *babeVerifier7,
-			header:   header7,
-			expErr:   ErrProducerEquivocated,
-		},
-		{
-			name:     "equivocate - secondary plain",
-			verifier: *babeVerifier8,
-			header:   header8,
-			expErr:   ErrProducerEquivocated,
-		},
-		{
-			name:     "equivocate - secondary vrf",
-			verifier: *babeVerifier9,
-			header:   header9,
-			expErr:   ErrProducerEquivocated,
-		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {