From e3d00878b3572aebe5024d7aa10c1512d1c63354 Mon Sep 17 00:00:00 2001
From: Alessandro Ros <aler9.dev@gmail.com>
Date: Thu, 19 Jan 2023 16:03:48 +0100
Subject: [PATCH] rtmp server: fix handshake and compatibility with streamlabs
 (#1244) (#1398)

---
 internal/rtmp/handshake/c2s2.go      |  7 +------
 internal/rtmp/handshake/handshake.go | 16 +++++++++++++---
 2 files changed, 14 insertions(+), 9 deletions(-)

diff --git a/internal/rtmp/handshake/c2s2.go b/internal/rtmp/handshake/c2s2.go
index 639458becc2..31f0c24c0c0 100644
--- a/internal/rtmp/handshake/c2s2.go
+++ b/internal/rtmp/handshake/c2s2.go
@@ -2,7 +2,6 @@ package handshake
 
 import (
 	"bytes"
-	"crypto/rand"
 	"fmt"
 	"io"
 )
@@ -51,11 +50,7 @@ func (c C2S2) Write(w io.Writer) error {
 	buf[6] = byte(c.Time2 >> 8)
 	buf[7] = byte(c.Time2)
 
-	if c.Random == nil {
-		rand.Read(buf[8:])
-	} else {
-		copy(buf[8:], c.Random)
-	}
+	copy(buf[8:], c.Random)
 
 	// signature
 	if c.Digest != nil {
diff --git a/internal/rtmp/handshake/handshake.go b/internal/rtmp/handshake/handshake.go
index a1a068e387b..95225b02578 100644
--- a/internal/rtmp/handshake/handshake.go
+++ b/internal/rtmp/handshake/handshake.go
@@ -29,12 +29,18 @@ func DoClient(rw io.ReadWriter, validateSignature bool) error {
 		return err
 	}
 
-	err = (&C2S2{Digest: c1.Digest}).Read(rw, validateSignature)
+	err = (&C2S2{
+		Digest: c1.Digest,
+	}).Read(rw, validateSignature)
 	if err != nil {
 		return err
 	}
 
-	err = C2S2{Digest: s1.Digest}.Write(rw)
+	err = C2S2{
+		Time:   s1.Time,
+		Random: s1.Random,
+		Digest: s1.Digest,
+	}.Write(rw)
 	if err != nil {
 		return err
 	}
@@ -66,7 +72,11 @@ func DoServer(rw io.ReadWriter, validateSignature bool) error {
 		return err
 	}
 
-	err = C2S2{Digest: c1.Digest}.Write(rw)
+	err = C2S2{
+		Time:   c1.Time,
+		Random: c1.Random,
+		Digest: c1.Digest,
+	}.Write(rw)
 	if err != nil {
 		return err
 	}