diff --git a/src/Rtmp/RtmpProtocol.cpp b/src/Rtmp/RtmpProtocol.cpp
index 686b389b..a5ee61c1 100644
--- a/src/Rtmp/RtmpProtocol.cpp
+++ b/src/Rtmp/RtmpProtocol.cpp
@@ -433,17 +433,19 @@ static u_int8_t FPKey[] = {
 //发送复杂握手c0c1
 void RtmpHandshake::create_complex_c0c1() {
     memcpy(zero, "\x80\x00\x07\x02", 4);
-    string str((char *) this, sizeof(*this));
+    //digest随机偏移长度
     auto offset_value = rand() % (C1_SCHEMA_SIZE - C1_OFFSET_SIZE - C1_DIGEST_SIZE);
-    str.erase(8 + C1_SCHEMA_SIZE + C1_OFFSET_SIZE + offset_value, C1_DIGEST_SIZE);
-
-    auto offset_ptr = (uint8_t *) str.data() + 8 + C1_SCHEMA_SIZE;
+    //设置digest偏移长度
+    auto offset_ptr = random + C1_SCHEMA_SIZE;
     offset_ptr[0] = offset_ptr[1] = offset_ptr[2] = offset_value / 4;
     offset_ptr[3] = offset_value - 3 * (offset_value / 4);
-
+    //去除digest后的剩余随机数据
+    string str((char *) this, sizeof(*this));
+    str.erase(8 + C1_SCHEMA_SIZE + C1_OFFSET_SIZE + offset_value, C1_DIGEST_SIZE);
+    //获取摘要
     auto digest_value = openssl_HMACsha256(FPKey, C1_FPKEY_SIZE, str.data(), str.size());
-    str.insert(8 + C1_SCHEMA_SIZE + C1_OFFSET_SIZE + offset_value, digest_value);
-    memcpy(this, str.data(), sizeof(*this));
+    //插入摘要
+    memcpy(random + C1_SCHEMA_SIZE + C1_OFFSET_SIZE + offset_value, digest_value.data(), digest_value.size());
 }
 
 void RtmpProtocol::check_C1_Digest(const string &digest,const string &data){