From f288e58c8181d3053b5b8aca017f885a812849e9 Mon Sep 17 00:00:00 2001
From: Jae Kwon <jae@tendermint.com>
Date: Sun, 20 Dec 2015 08:18:39 -0800
Subject: [PATCH] Prefix TMSP messages with length

---
 consensus/common_test.go         |  2 +-
 mempool/mempool_test.go          |  2 +-
 node/node_test.go                |  2 +-
 proxy/remote_app_context.go      | 14 +++++++++++---
 proxy/remote_app_context_test.go |  2 +-
 5 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/consensus/common_test.go b/consensus/common_test.go
index 94b30dd68..c0b82c3cf 100644
--- a/consensus/common_test.go
+++ b/consensus/common_test.go
@@ -16,7 +16,7 @@ import (
 	sm "github.com/tendermint/tendermint/state"
 	"github.com/tendermint/tendermint/types"
 
-	"github.com/tendermint/tmsp/example"
+	"github.com/tendermint/tmsp/example/golang"
 )
 
 var chainID string
diff --git a/mempool/mempool_test.go b/mempool/mempool_test.go
index a3c5cff01..bdf326fa4 100644
--- a/mempool/mempool_test.go
+++ b/mempool/mempool_test.go
@@ -6,7 +6,7 @@ import (
 
 	"github.com/tendermint/tendermint/proxy"
 	"github.com/tendermint/tendermint/types"
-	"github.com/tendermint/tmsp/example"
+	"github.com/tendermint/tmsp/example/golang"
 	tmsp "github.com/tendermint/tmsp/types"
 )
 
diff --git a/node/node_test.go b/node/node_test.go
index 49e7d3ddf..135d5444b 100644
--- a/node/node_test.go
+++ b/node/node_test.go
@@ -7,7 +7,7 @@ import (
 	. "github.com/tendermint/go-common"
 	"github.com/tendermint/go-p2p"
 	_ "github.com/tendermint/tendermint/config/tendermint_test"
-	"github.com/tendermint/tmsp/example"
+	"github.com/tendermint/tmsp/example/golang"
 	"github.com/tendermint/tmsp/server"
 )
 
diff --git a/proxy/remote_app_context.go b/proxy/remote_app_context.go
index dd96abe74..df638f3e5 100644
--- a/proxy/remote_app_context.go
+++ b/proxy/remote_app_context.go
@@ -2,6 +2,7 @@ package proxy
 
 import (
 	"bufio"
+	"bytes"
 	"container/list"
 	"errors"
 	"fmt"
@@ -83,7 +84,7 @@ func (app *remoteAppContext) Error() error {
 
 func (app *remoteAppContext) sendRequestsRoutine() {
 	for {
-		var n int
+		var n, n2 int
 		var err error
 		select {
 		case <-app.QuitService.Quit:
@@ -92,7 +93,10 @@ func (app *remoteAppContext) sendRequestsRoutine() {
 
 			app.willSendReq(reqres)
 
-			wire.WriteBinary(reqres.Request, app.bufWriter, &n, &err)
+			buf := new(bytes.Buffer)
+			wire.WriteBinary(reqres.Request, buf, &n2, &err) // Length prefix
+			wire.WriteVarint(buf.Len(), app.bufWriter, &n, &err)
+			wire.WriteTo(buf.Bytes(), app.bufWriter, &n, &err)
 			if err != nil {
 				app.StopForError(err)
 				return
@@ -113,13 +117,17 @@ func (app *remoteAppContext) recvResponseRoutine() {
 	r := bufio.NewReader(app.conn) // Buffer reads
 	for {
 		var res tmsp.Response
-		var n int
+		var n, n2 int
 		var err error
+		size := wire.ReadVarint(r, &n2, &err)
 		wire.ReadBinaryPtr(&res, r, maxResponseSize, &n, &err)
 		if err != nil {
 			app.StopForError(err)
 			return
 		}
+		if size != n {
+			app.StopForError(fmt.Errorf("Prefixed length not equal to actual length. %v vs %v", size, n))
+		}
 		switch res := res.(type) {
 		case tmsp.ResponseException:
 			app.StopForError(errors.New(res.Error))
diff --git a/proxy/remote_app_context_test.go b/proxy/remote_app_context_test.go
index 15e97eee7..1242b6c83 100644
--- a/proxy/remote_app_context_test.go
+++ b/proxy/remote_app_context_test.go
@@ -7,7 +7,7 @@ import (
 
 	. "github.com/tendermint/go-common"
 	"github.com/tendermint/go-logio"
-	example "github.com/tendermint/tmsp/example"
+	"github.com/tendermint/tmsp/example/golang"
 	"github.com/tendermint/tmsp/server"
 )