Reset pushed stream unless using GET or HEAD method.

net/spdy/chromium/spdy_session.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/spdy/chromium/spdy_session.h"
 
 #include <algorithm>
 #include <limits>
 #include <map>
 #include <utility>
@@ skipping 1647 matching lines @@
   UnclaimedPushedStreamContainer::const_iterator pushed_it =
       unclaimed_pushed_streams_.lower_bound(gurl);
   if (pushed_it != unclaimed_pushed_streams_.end() &&
       pushed_it->first == gurl) {
     EnqueueResetStreamFrame(
         stream_id, request_priority, ERROR_CODE_REFUSED_STREAM,
         "Received duplicate pushed stream with url: " + gurl.spec());
     return;
   }
 
+  // "Promised requests MUST be cacheable and MUST be safe [...]" (RFC7540
+  // Section 8.2).  Only cacheable safe request methods are GET and HEAD.
+  SpdyHeaderBlock::const_iterator it = headers.find(":method");
+  if (it == headers.end() ||
+      (it->second.compare("GET") != 0 && it->second.compare("HEAD") != 0)) {
+    EnqueueResetStreamFrame(
+        stream_id, request_priority, ERROR_CODE_REFUSED_STREAM,
+        SpdyStringPrintf(
+            "Rejected push stream %d due to inadequate request method",
+            associated_stream_id));
+    return;
+  }
+
   auto stream = base::MakeUnique<SpdyStream>(
       SPDY_PUSH_STREAM, GetWeakPtr(), gurl, request_priority,
       stream_initial_send_window_size_, stream_max_recv_window_size_, net_log_);
   stream->set_stream_id(stream_id);
 
   // Convert RequestPriority to a SpdyPriority to send in a PRIORITY frame.
   SpdyPriority spdy_priority =
       ConvertRequestPriorityToSpdyPriority(request_priority);
   SpdyStreamId dependency_id = 0;
   bool exclusive = false;
@@ skipping 1539 matching lines @@
     if (!queue->empty()) {
       SpdyStreamId stream_id = queue->front();
       queue->pop_front();
       return stream_id;
     }
   }
   return 0;
 }
 
 }  // namespace net