[FAB-3549] Peer panic from bad block bytes

This CR fixes two situations that led to peer panics: 1) the block
passed to GetChainIDFromBlock was nil, and 2) the payload header within
the block was nil.

It also tests the path through the CSCC, which resulted in a panic when
the payload header was nil.

Change-Id: Ice827d292823f12fead0756e956d9851770b2566
Signed-off-by: Will Lahti <[email protected]>

Author: wlahti

core/scc/cscc/configure_test.go

@@ -42,6 +42,7 @@ import (
 	"github.com/hyperledger/fabric/msp/mgmt/testtools"
 	peergossip "github.com/hyperledger/fabric/peer/gossip"
 	"github.com/hyperledger/fabric/peer/gossip/mocks"
+	cb "github.com/hyperledger/fabric/protos/common"
 	pb "github.com/hyperledger/fabric/protos/peer"
 	"github.com/hyperledger/fabric/protos/utils"
 	"github.com/spf13/viper"
@@ -214,6 +215,20 @@ func TestConfigerInvokeJoinChainCorrectParams(t *testing.T) {
 	res := stub.MockInvokeWithSignedProposal("2", [][]byte{[]byte("JoinChain"), nil}, sProp)
 	assert.Equal(t, res.Status, int32(shim.ERROR))
 
+	// Try fail path with block and nil payload header
+	payload, _ := proto.Marshal(&cb.Payload{})
+	env, _ := proto.Marshal(&cb.Envelope{
+		Payload: payload,
+	})
+	badBlock := &cb.Block{
+		Data: &cb.BlockData{
+			Data: [][]byte{env},
+		},
+	}
+	badBlockBytes := utils.MarshalOrPanic(badBlock)
+	res = stub.MockInvokeWithSignedProposal("2", [][]byte{[]byte("JoinChain"), badBlockBytes}, sProp)
+	assert.Equal(t, res.Status, int32(shim.ERROR))
+
 	// Now, continue with valid execution path
 	if res := stub.MockInvokeWithSignedProposal("2", args, sProp); res.Status != shim.OK {
 		t.Fatalf("cscc invoke JoinChain failed with: %v", res.Message)

protos/utils/blockutils.go

@@ -35,19 +35,22 @@ func GetChainIDFromBlockBytes(bytes []byte) (string, error) {
 
 // GetChainIDFromBlock returns chain ID in the block
 func GetChainIDFromBlock(block *cb.Block) (string, error) {
-	if block.Data == nil || block.Data.Data == nil || len(block.Data.Data) == 0 {
-		return "", fmt.Errorf("Failed to find chain ID because the block is empty.")
+	if block == nil || block.Data == nil || block.Data.Data == nil || len(block.Data.Data) == 0 {
+		return "", fmt.Errorf("failed to retrieve channel id - block is empty")
 	}
 	var err error
 	envelope := &cb.Envelope{}
 	if err = proto.Unmarshal(block.Data.Data[0], envelope); err != nil {
-		return "", fmt.Errorf("Error reconstructing envelope(%s)", err)
+		return "", fmt.Errorf("error reconstructing envelope(%s)", err)
 	}
 	payload := &cb.Payload{}
 	if err = proto.Unmarshal(envelope.Payload, payload); err != nil {
-		return "", fmt.Errorf("Error reconstructing payload(%s)", err)
+		return "", fmt.Errorf("error reconstructing payload(%s)", err)
 	}
 
+	if payload.Header == nil {
+		return "", fmt.Errorf("failed to retrieve channel id - payload header is empty")
+	}
 	chdr, err := UnmarshalChannelHeader(payload.Header.ChannelHeader)
 	if err != nil {
 		return "", err

protos/utils/blockutils_test.go

@@ -48,6 +48,10 @@ func TestGetChainIDFromBlock(t *testing.T) {
 	var gb *common.Block
 	var cid string
 
+	// nil block
+	_, err = utils.GetChainIDFromBlock(gb)
+	assert.Error(t, err, "Expected error getting channel id from nil block")
+
 	gb, err = configtxtest.MakeGenesisBlock(testChainID)
 	assert.NoError(t, err, "Failed to create test configuration block")
 
@@ -98,6 +102,19 @@ func TestGetChainIDFromBlock(t *testing.T) {
 	}
 	_, err = utils.GetChainIDFromBlock(badBlock)
 	assert.Error(t, err, "Expected error with malformed channel header")
+
+	// nil payload header
+	payload, _ = proto.Marshal(&cb.Payload{})
+	env, _ = proto.Marshal(&cb.Envelope{
+		Payload: payload,
+	})
+	badBlock = &cb.Block{
+		Data: &cb.BlockData{
+			Data: [][]byte{env},
+		},
+	}
+	_, err = utils.GetChainIDFromBlock(badBlock)
+	assert.Error(t, err, "Expected error when payload header is nil")
 }
 
 func TestGetBlockFromBlockBytes(t *testing.T) {