BFT Block Puller: verify attestation

Signed-off-by: Yoav Tock <tock@il.ibm.com>
Change-Id: Ia34ff4536453581895c4f13b2d73f0e7066ce125

gossip/api/crypto.go

@@ -37,6 +37,11 @@ type MessageCryptoService interface {
 	// else returns error
 	VerifyBlock(channelID common.ChannelID, seqNum uint64, block *cb.Block) error
 
+	// VerifyBlockAttestation does the same as VerifyBlock, except it assumes block.Data = nil. It therefore does not
+	// compute the block.Data.Hash() and compare it to the block.Header.DataHash. This is used when the orderer
+	// delivers a block with header & metadata only, as an attestation of block existence.
+	VerifyBlockAttestation(channelID string, block *cb.Block) error
+
 	// Sign signs msg with this peer's signing key and outputs
 	// the signature if no error occurred.
 	Sign(msg []byte) ([]byte, error)

gossip/comm/comm_test.go

@@ -97,6 +97,12 @@ func (*naiveSecProvider) VerifyBlock(channelID common.ChannelID, seqNum uint64,
 	return nil
 }
 
+// VerifyBlockAttestation returns nil if the block attestation is properly signed,
+// else returns error
+func (*naiveSecProvider) VerifyBlockAttestation(channelID string, signedBlock *cb.Block) error {
+	return nil
+}
+
 // Sign signs msg with this peer's signing key and outputs
 // the signature if no error occurred.
 func (*naiveSecProvider) Sign(msg []byte) ([]byte, error) {

gossip/gossip/channel/channel_test.go

@@ -146,6 +146,10 @@ func (cs *cryptoService) VerifyBlock(channelID common.ChannelID, seqNum uint64,
 	return args.Get(0).(error)
 }
 
+func (*cryptoService) VerifyBlockAttestation(channelID string, signedBlock *cb.Block) error {
+	panic("Should not be called in this test")
+}
+
 func (cs *cryptoService) Sign(msg []byte) ([]byte, error) {
 	panic("Should not be called in this test")
 }

gossip/gossip/gossip_test.go

@@ -177,6 +177,12 @@ func (*naiveCryptoService) VerifyBlock(channelID common.ChannelID, seqNum uint64
 	return nil
 }
 
+// VerifyBlockAttestation returns nil if the block attestation is properly signed,
+// else returns error
+func (*naiveCryptoService) VerifyBlockAttestation(channelID string, signedBlock *cb.Block) error {
+	return nil
+}
+
 // Sign signs msg with this peer's signing key and outputs
 // the signature if no error occurred.
 func (*naiveCryptoService) Sign(msg []byte) ([]byte, error) {

gossip/gossip/orgs_test.go

@@ -81,6 +81,12 @@ func (*configurableCryptoService) VerifyBlock(channelID common.ChannelID, seqNum
 	return nil
 }
 
+// VerifyBlockAttestation returns nil if the block attestation is properly signed,
+// else returns error
+func (*configurableCryptoService) VerifyBlockAttestation(channelID string, signedBlock *cb.Block) error {
+	return nil
+}
+
 // Sign signs msg with this peer's signing key and outputs
 // the signature if no error occurred.
 func (*configurableCryptoService) Sign(msg []byte) ([]byte, error) {

gossip/identity/identity_test.go

@@ -82,6 +82,12 @@ func (*naiveCryptoService) VerifyBlock(channelID common.ChannelID, seqNum uint64
 	return nil
 }
 
+// VerifyBlockAttestation returns nil if the block attestation is properly signed,
+// else returns error
+func (*naiveCryptoService) VerifyBlockAttestation(channelID string, signedBlock *cb.Block) error {
+	return nil
+}
+
 // VerifyByChannel verifies a peer's signature on a message in the context
 // of a specific channel
 func (*naiveCryptoService) VerifyByChannel(_ common.ChannelID, _ api.PeerIdentityType, _, _ []byte) error {

gossip/service/gossip_service_test.go

@@ -843,6 +843,12 @@ func (*naiveCryptoService) VerifyBlock(chainID gossipcommon.ChannelID, seqNum ui
 	return nil
 }
 
+// VerifyBlockAttestation returns nil if the block attestation is properly signed,
+// else returns error
+func (*naiveCryptoService) VerifyBlockAttestation(channelID string, signedBlock *common.Block) error {
+	return nil
+}
+
 // Sign signs msg with this peer's signing key and outputs
 // the signature if no error occurred.
 func (*naiveCryptoService) Sign(msg []byte) ([]byte, error) {

gossip/state/state_test.go

@@ -121,6 +121,12 @@ func (*cryptoServiceMock) VerifyBlock(channelID common.ChannelID, seqNum uint64,
 	return nil
 }
 
+// VerifyBlockAttestation returns nil if the block attestation is properly signed,
+// else returns error
+func (*cryptoServiceMock) VerifyBlockAttestation(channelID string, signedBlock *pcomm.Block) error {
+	return nil
+}
+
 // Sign signs msg with this peer's signing key and outputs
 // the signature if no error occurred.
 func (*cryptoServiceMock) Sign(msg []byte) ([]byte, error) {

internal/peer/gossip/mcs.go

@@ -122,6 +122,8 @@ func (s *MSPMessageCryptoService) GetPKIidOfCert(peerIdentity api.PeerIdentityTy
 	return digest
 }
 
+// TODO BP
+
 // VerifyBlock returns nil if the block is properly signed, and the claimed seqNum is the
 // sequence number that the block's header contains.
 // else returns error
@@ -156,6 +158,10 @@ func (s *MSPMessageCryptoService) VerifyBlock(chainID common.ChannelID, seqNum u
 		return fmt.Errorf("Header.DataHash is different from Hash(block.Data) for block with id [%d] on channel [%s]", block.Header.Number, chainID)
 	}
 
+	return s.verifyHeaderAndMetadata(channelID, block)
+}
+
+func (s *MSPMessageCryptoService) verifyHeaderAndMetadata(channelID string, block *pcommon.Block) error {
 	// Get the policy manager for channelID
 	cpm := s.channelPolicyManagerGetter.Manager(channelID)
 	if cpm == nil {
@@ -184,6 +190,25 @@ func (s *MSPMessageCryptoService) VerifyBlock(chainID common.ChannelID, seqNum u
 	return verifier(block.Header, block.Metadata)
 }
 
+// VerifyBlockAttestation returns nil when the header matches the metadata signature. It assumed the block.Data is nil
+// and therefore does not verify that Header.DataHash is equal to the hash of block.Data. This is used when the orderer
+// delivers a block with header & metadata only, as an attestation of block existence.
+func (s *MSPMessageCryptoService) VerifyBlockAttestation(chainID string, block *pcommon.Block) error {
+	if block == nil {
+		return fmt.Errorf("Invalid Block on channel [%s]. Block is nil.", chainID)
+	}
+	if block.Header == nil {
+		return fmt.Errorf("Invalid Block on channel [%s]. Header must be different from nil.", chainID)
+	}
+
+	// - Unmarshal medatada
+	if block.Metadata == nil || len(block.Metadata.Metadata) == 0 {
+		return fmt.Errorf("Block with id [%d] on channel [%s] does not have metadata. Block not valid.", block.Header.Number, chainID)
+	}
+
+	return s.verifyHeaderAndMetadata(chainID, block)
+}
+
 // Sign signs msg with this peer's signing key and outputs
 // the signature if no error occurred.
 func (s *MSPMessageCryptoService) Sign(msg []byte) ([]byte, error) {

internal/peer/gossip/mcs_test.go

@@ -28,6 +28,7 @@ import (
 	"github.com/hyperledger/fabric/msp"
 	"github.com/hyperledger/fabric/msp/mgmt"
 	"github.com/hyperledger/fabric/protoutil"
+	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/mock"
 	"github.com/stretchr/testify/require"
 )
@@ -289,28 +290,68 @@ func TestVerifyBlock(t *testing.T) {
 	blockRaw2, msg2 := mockBlock(t, "D", 42, aliceSigner, nil)
 	policyManagerGetter.Managers["D"].(*mocks.ChannelPolicyManager).Policy.(*mocks.Policy).Deserializer.(*mocks.IdentityDeserializer).Msg = msg2
 
-	// - Verify block
-	require.NoError(t, msgCryptoService.VerifyBlock([]byte("C"), 42, blockRaw))
-	// Wrong sequence number claimed
-	err = msgCryptoService.VerifyBlock([]byte("C"), 43, blockRaw)
-	require.Error(t, err)
-	require.Contains(t, err.Error(), "but actual seqNum inside block is")
-	delete(policyManagerGetter.Managers, "D")
-	nilPolMgrErr := msgCryptoService.VerifyBlock([]byte("D"), 42, blockRaw2)
-	require.Contains(t, nilPolMgrErr.Error(), "Could not acquire policy manager")
-	require.Error(t, nilPolMgrErr)
-	require.Error(t, msgCryptoService.VerifyBlock([]byte("A"), 42, blockRaw))
-	require.Error(t, msgCryptoService.VerifyBlock([]byte("B"), 42, blockRaw))
-
-	// - Prepare testing invalid block (wrong data has), Alice signs it.
-	blockRaw, msg = mockBlock(t, "C", 42, aliceSigner, []byte{0})
-	policyManagerGetter.Managers["C"].(*mocks.ChannelPolicyManager).Policy.(*mocks.Policy).Deserializer.(*mocks.IdentityDeserializer).Msg = msg
-
-	// - Verify block
-	require.Error(t, msgCryptoService.VerifyBlock([]byte("C"), 42, blockRaw))
+	t.Run("verify block", func(t *testing.T) {
+		require.NoError(t, msgCryptoService.VerifyBlock([]byte("C"), 42, blockRaw))
+		// Wrong sequence number claimed
+		err = msgCryptoService.VerifyBlock([]byte("C"), 43, blockRaw)
+		require.Error(t, err)
+		require.Contains(t, err.Error(), "but actual seqNum inside block is")
+		delete(policyManagerGetter.Managers, "D")
+		nilPolMgrErr := msgCryptoService.VerifyBlock([]byte("D"), 42, blockRaw2)
+		require.Contains(t, nilPolMgrErr.Error(), "Could not acquire policy manager")
+		require.Error(t, nilPolMgrErr)
+		require.Error(t, msgCryptoService.VerifyBlock([]byte("A"), 42, blockRaw))
+		require.Error(t, msgCryptoService.VerifyBlock([]byte("B"), 42, blockRaw))
+
+		// - Prepare testing invalid block (wrong data has), Alice signs it.
+		blockRawInvalid, msgInvalid := mockBlock(t, "C", 42, aliceSigner, []byte{0})
+		policyManagerGetter.Managers["C"].(*mocks.ChannelPolicyManager).Policy.(*mocks.Policy).Deserializer.(*mocks.IdentityDeserializer).Msg = msgInvalid
+		defer func() {
+			policyManagerGetter.Managers["C"].(*mocks.ChannelPolicyManager).Policy.(*mocks.Policy).Deserializer.(*mocks.IdentityDeserializer).Msg = msg
+		}()
+
+		// - Verify block
+		require.Error(t, msgCryptoService.VerifyBlock([]byte("C"), 42, blockRawInvalid))
+
+		// Check invalid args
+		require.Error(t, msgCryptoService.VerifyBlock([]byte("C"), 42, &common.Block{}))
+	})
 
-	// Check invalid args
-	require.Error(t, msgCryptoService.VerifyBlock([]byte("C"), 42, &common.Block{}))
+	t.Run("verify block attestation", func(t *testing.T) {
+		// An attestation is a signed block with block.Data = nil
+		attestation := blockRaw
+		attestation.Data = nil
+		attestation2 := blockRaw2
+		attestation2.Data = nil
+
+		assert.NoError(t, msgCryptoService.VerifyBlockAttestation("C", attestation))
+		delete(policyManagerGetter.Managers, "D")
+		nilPolMgrErr := msgCryptoService.VerifyBlockAttestation("D", attestation2)
+		assert.Contains(t, nilPolMgrErr.Error(), "Could not acquire policy manager")
+		assert.Error(t, nilPolMgrErr)
+		assert.Error(t, msgCryptoService.VerifyBlockAttestation("A", attestation))
+		assert.Error(t, msgCryptoService.VerifyBlockAttestation("B", attestation))
+
+		// - Prepare testing invalid attestation (wrong data has), Alice signs it.
+		// - Prepare testing invalid attestation (wrong data has), Alice signs it.
+		_, msgInvalid := mockBlock(t, "C", 42, aliceSigner, []byte{0})
+		policyManagerGetter.Managers["C"].(*mocks.ChannelPolicyManager).Policy.(*mocks.Policy).Deserializer.(*mocks.IdentityDeserializer).Msg = msgInvalid
+		defer func() {
+			policyManagerGetter.Managers["C"].(*mocks.ChannelPolicyManager).Policy.(*mocks.Policy).Deserializer.(*mocks.IdentityDeserializer).Msg = msg
+		}()
+
+		// - Verify attestation
+		assert.Error(t, msgCryptoService.VerifyBlockAttestation("C", attestation))
+
+		// Check invalid args
+		attestation.Header.DataHash = []byte{0, 1, 2, 3, 4}
+		assert.Error(t, msgCryptoService.VerifyBlockAttestation("C", attestation))
+		attestation.Metadata = nil
+		assert.Error(t, msgCryptoService.VerifyBlockAttestation("C", attestation))
+		attestation.Header = nil
+		assert.Error(t, msgCryptoService.VerifyBlockAttestation("C", attestation))
+		assert.Error(t, msgCryptoService.VerifyBlockAttestation("C", nil))
+	})
 }
 
 func TestVerifyBlockBFT(t *testing.T) {

internal/pkg/peer/blocksprovider/blocksprovider.go

@@ -66,6 +66,11 @@ type GossipServiceAdapter interface {
 //go:generate counterfeiter -o fake/block_verifier.go --fake-name BlockVerifier . BlockVerifier
 type BlockVerifier interface {
 	VerifyBlock(channelID gossipcommon.ChannelID, blockNum uint64, block *common.Block) error
+
+	// VerifyBlockAttestation does the same as VerifyBlock, except it assumes block.Data = nil. It therefore does not
+	// compute the block.Data.Hash() and compare it to the block.Header.DataHash. This is used when the orderer
+	// delivers a block with header & metadata only, as an attestation of block existence.
+	VerifyBlockAttestation(channelID string, block *common.Block) error
 }
 
 //go:generate counterfeiter -o fake/orderer_connection_source.go --fake-name OrdererConnectionSource . OrdererConnectionSource