Reject unadvertised encodings

net/url_request/url_request_http_job.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/url_request/url_request_http_job.h"
 
 #include <vector>
 
 #include "base/base_switches.h"
 #include "base/bind.h"
@@ skipping 1059 matching lines @@
       types.push_back(SourceStream::TYPE_DEFLATE);
     } else if (base::LowerCaseEqualsASCII(type, kGZip) ||
                base::LowerCaseEqualsASCII(type, kXGZip)) {
       types.push_back(SourceStream::TYPE_GZIP);
     } else if (base::LowerCaseEqualsASCII(type, kSdch)) {
       // If SDCH support is not configured, pass through raw response.
       if (!request()->context()->sdch_manager())
         return upstream;
       types.push_back(SourceStream::TYPE_SDCH);
     } else {
       // Unknown encoding type. Pass through raw response body.

[Randy Smith (Not in Mondays), 2017/03/21 21:23:20]

Would you be willing to put an entry in here for the unknown content encoding
(in a separate comment I'm advocating for using YA new entry in the enum,
REJECTED, in HttpNetworkTransaction, so this would be the only use of the
unknown type)?  This isn't needed for this CL, but it's simple to add, and would
aid in the work I'm trying to do to figure out if we can deprecate passing
through unknown encodings.

[eustas, 2017/03/27 10:27:11]

Yup, but I didn't get what item should be added...
Report UNKNOWN to UMA and return nullptr?

[Randy Smith (Not in Mondays), 2017/03/28 19:55:36]

Just report UNKNOWN--we can't change the behavior.  

       return upstream;
     }
   }
 
   // Sdch specific hacks:
   std::string mime_type;
   bool success = GetMimeType(&mime_type);
   DCHECK(success || mime_type.empty());
   SdchPolicyDelegate::FixUpSdchContentEncodings(
       request()->net_log(), mime_type, dictionaries_advertised_.get(), &types);
@@ skipping 21 matching lines @@
         }
         break;
       }
       case SourceStream::TYPE_GZIP:
       case SourceStream::TYPE_DEFLATE:
       case SourceStream::TYPE_GZIP_FALLBACK:
         downstream = GzipSourceStream::Create(std::move(upstream), type);
         break;
       case SourceStream::TYPE_NONE:
       case SourceStream::TYPE_INVALID:
+      case SourceStream::TYPE_UNKNOWN:
       case SourceStream::TYPE_MAX:
         NOTREACHED();
         return nullptr;
     }
     if (downstream == nullptr)
       return nullptr;
     upstream = std::move(downstream);
   }
 
   return upstream;
@@ skipping 419 matching lines @@
   awaiting_callback_ = false;
 
   // Notify NetworkQualityEstimator.
   NetworkQualityEstimator* network_quality_estimator =
       request()->context()->network_quality_estimator();
   if (network_quality_estimator)
     network_quality_estimator->NotifyURLRequestDestroyed(*request());
 }
 
 }  // namespace net