Define NGHTTP2_CLEARTEXT_PROTO_VERSION_ID

This identifier string is used if HTTP/2 is used over cleartext TCP.

lib/includes/nghttp2/nghttp2.h

@@ -38,7 +38,8 @@ extern "C" {
 /**
  * @macro
  *
- * The protocol version identification of this library supports.
+ * The protocol version identification string of this library
+ * supports.  This identifier is used if HTTP/2 is used over TLS.
  */
 #define NGHTTP2_PROTO_VERSION_ID "h2-10"
 /**
@@ -48,6 +49,22 @@ extern "C" {
  */
 #define NGHTTP2_PROTO_VERSION_ID_LEN 5
 
+/**
+ * @macro
+ *
+ * The protocol version identification string of this library
+ * supports.  This identifier is used if HTTP/2 is used over cleartext
+ * TCP.
+ */
+#define NGHTTP2_CLEARTEXT_PROTO_VERSION_ID "h2c-10"
+
+/**
+ * @macro
+ *
+ * The length of :macro:`NGHTTP2_CLEARTEXT_PROTO_VERSION_ID`.
+ */
+#define NGHTTP2_CLEARTEXT_PROTO_VERSION_ID_LEN 6
+
 struct nghttp2_session;
 /**
  * @struct

src/nghttp.cc

@@ -611,7 +611,7 @@ struct HttpClient {
     req += hostport;
     req += "\r\n"
       "Connection: Upgrade, HTTP2-Settings\r\n"
-      "Upgrade: " NGHTTP2_PROTO_VERSION_ID "\r\n"
+      "Upgrade: " NGHTTP2_CLEARTEXT_PROTO_VERSION_ID "\r\n"
       "HTTP2-Settings: ";
     req += token68;
     req += "\r\n"

src/shrpx_client_handler.cc

@@ -542,7 +542,7 @@ int ClientHandler::perform_http2_upgrade(HttpsUpstream *http)
   set_bev_cb(upstream_http2_connhd_readcb, upstream_writecb, upstream_eventcb);
   static char res[] = "HTTP/1.1 101 Switching Protocols\r\n"
     "Connection: Upgrade\r\n"
-    "Upgrade: " NGHTTP2_PROTO_VERSION_ID "\r\n"
+    "Upgrade: " NGHTTP2_CLEARTEXT_PROTO_VERSION_ID "\r\n"
     "\r\n";
   rv = bufferevent_write(bev_, res, sizeof(res) - 1);
   if(rv != 0) {

src/shrpx_downstream.cc

@@ -734,10 +734,12 @@ bool Downstream::http2_upgrade_request() const
   bool upgrade_seen = false;
   bool http2_settings_seen = false;
   for(auto& hd : request_headers_) {
-    // For now just check NGHTTP2_PROTO_VERSION_ID in Upgrade header
-    // field and existence of HTTP2-Settings header field.
+    // For now just check NGHTTP2_CLEARTEXT_PROTO_VERSION_ID in
+    // Upgrade header field and existence of HTTP2-Settings header
+    // field.
     if(util::strieq(hd.first.c_str(), "upgrade")) {
-       if(util::strieq(hd.second.c_str(), NGHTTP2_PROTO_VERSION_ID)) {
+       if(util::strieq(hd.second.c_str(),
+                       NGHTTP2_CLEARTEXT_PROTO_VERSION_ID)) {
         upgrade_seen = true;
       }
     } else if(util::strieq(hd.first.c_str(), "http2-settings")) {