cors: allow using regexes to match origins (#3769)

Resolves https://github.com/envoyproxy/envoy/issues/2526

Signed-off-by: Neri Marschik <codesuki@users.noreply.github.com>

Mirrored from https://github.com/envoyproxy/envoy @ 00bb039a78f66b7cd42acedd9b2d3dc52bfb605d

envoy/api/v2/route/route.proto

@@ -282,10 +282,18 @@ message RouteMatch {
   repeated QueryParameterMatcher query_parameters = 7;
 }
 
+// [#comment:next free field: 9]
 message CorsPolicy {
   // Specifies the origins that will be allowed to do CORS requests.
+  //
+  // An origin is allowed if either allow_origin or allow_origin_regex match.
   repeated string allow_origin = 1;
 
+  // Specifies regex patterns that match allowed origins.
+  //
+  // An origin is allowed if either allow_origin or allow_origin_regex match.
+  repeated string allow_origin_regex = 8;
+
   // Specifies the content for the *access-control-allow-methods* header.
   string allow_methods = 2;