add option to validate messages against expected tipset

chain/exchange/client.go

@@ -215,6 +215,22 @@ func (c *client) processResponse(req *Request, res *Response) (*validatedRespons
 				return nil, err
 			}
 		}
+
+		if options.ValidateMessages {
+			chain := make([]*BSTipSet, 0, resLength)
+			for i, resChain := range res.Chain {
+				next := &BSTipSet{
+					Blocks:   req.TipSets[i].Blocks(),
+					Messages: resChain.Messages,
+				}
+				chain = append(chain, next)
+			}
+
+			err := c.validateCompressedIndices(chain)
+			if err != nil {
+				return nil, err
+			}
+		}
 	}
 
 	return validRes, nil

chain/exchange/protocol.go

@@ -57,6 +57,8 @@ type Request struct {
 	// Request options, see `Options` type for more details. Compressed
 	// in a single `uint64` to save space.
 	Options uint64
+	// Request tipsets for validation
+	TipSets []*types.TipSet
 }
 
 // `Request` processed and validated to query the tipsets needed.
@@ -71,6 +73,7 @@ type validatedRequest struct {
 const (
 	Headers = 1 << iota
 	Messages
+	Validate
 )
 
 // Decompressed options into separate struct members for easy access
@@ -78,6 +81,7 @@ const (
 type parsedOptions struct {
 	IncludeHeaders   bool
 	IncludeMessages  bool
+	ValidateMessages bool
 }
 
 func (options *parsedOptions) noOptionsSet() bool {
@@ -89,6 +93,7 @@ func parseOptions(optfield uint64) *parsedOptions {
 	return &parsedOptions{
 		IncludeHeaders:   optfield&(uint64(Headers)) != 0,
 		IncludeMessages:  optfield&(uint64(Messages)) != 0,
+		ValidateMessages: optfield&(uint64(Validate)) != 0,
 	}
 }