api: Validate header names fields (#21162)

Signed-off-by: Andre Vehreschild <vehre@x41-dsec.de>

Mirrored from https://github.com/envoyproxy/envoy @ 90fe16cda2b5d20f77775f86176571d6c13ce94d

envoy/extensions/filters/http/bandwidth_limit/v3/bandwidth_limit.proto

@@ -81,5 +81,6 @@ message BandwidthLimit {
   bool enable_response_trailers = 6;
 
   // Optional The prefix for the response trailers.
-  string response_trailer_prefix = 7;
+  string response_trailer_prefix = 7
+      [(validate.rules).string = {well_known_regex: HTTP_HEADER_NAME strict: false}];
 }

envoy/extensions/filters/http/grpc_http1_reverse_bridge/v3/config.proto

@@ -47,7 +47,8 @@ message FilterConfig {
   //
   // Envoy will treat the upstream response as an error if this option is specified and the header
   // is missing or if the value does not match the actual response body size.
-  string response_size_header = 3;
+  string response_size_header = 3
+      [(validate.rules).string = {well_known_regex: HTTP_HEADER_NAME strict: false}];
 }
 
 // gRPC reverse bridge filter configuration per virtualhost/route/weighted-cluster level.