Sanitize headers in Proxy Authentication Required responses

net/http/proxy_client_socket.cc

Index: net/http/proxy_client_socket.cc
diff --git a/net/http/proxy_client_socket.cc b/net/http/proxy_client_socket.cc
index dcfae037ce721c92bd95dfa3aeded77bd2f6bf62..580c2112dd1fff03488e372336bffb7521dd8e92 100644
--- a/net/http/proxy_client_socket.cc
+++ b/net/http/proxy_client_socket.cc
@@ -17,6 +17,20 @@
 
 namespace net {
 
+namespace {
+
+void CopyHeaderValues(scoped_refptr<HttpResponseHeaders> source,
+                      scoped_refptr<HttpResponseHeaders> dest,
+                      const std::string& header_name) {
+  void* iter = NULL;
+  std::string header_value;
+
+  while (source->EnumerateHeader(&iter, header_name, &header_value))
+    dest->AddHeader(header_name + ": " + header_value);
+}
+
+}  // namespace
+
 // static
 void ProxyClientSocket::BuildTunnelRequest(
     const HttpRequestInfo& request_info,
@@ -72,22 +86,39 @@ void ProxyClientSocket::LogBlockedTunnelResponse(int http_status_code,
 }
 
 // static
-bool ProxyClientSocket::SanitizeProxyRedirect(HttpResponseInfo* response,
-                                              const GURL& url) {
+bool ProxyClientSocket::SanitizeProxyAuth(HttpResponseInfo* response) {
+  DCHECK(response && response->headers.get());
+
+  scoped_refptr<HttpResponseHeaders> old_headers = response->headers;
+
+  const char* kHeaders = "HTTP/1.1 407 Proxy Authentication Required\n\n";
+  scoped_refptr<HttpResponseHeaders> new_headers = new HttpResponseHeaders(
+      HttpUtil::AssembleRawHeaders(kHeaders, strlen(kHeaders)));
+
+  new_headers->ReplaceStatusLine(old_headers->GetStatusLine());
+  CopyHeaderValues(old_headers, new_headers, "Connection");

[Ryan Hamilton, 2014/12/19 21:26:59]

I sure would have thought that you'd need both Connection and Content-length (or
a synthetic C-L). Do you understand why Content-Length is not required?

[Ryan Sleevi, 2014/12/19 21:30:25]

Agreed. This is why I have trouble understanding how this doesn't break
something.

If a proxy sends a response along with the initial body, and we're going to
re-use that connection, we need the presence of Keep-Alive (either implicit or
explicit) and the ability to drain the body.

I don't think the tests send dummy bodies, and so it falls under the
"IsConnectedAndIdle" check and decides it doesn't need to drain the body. But we
should.

[Deprecated (see juliatuttle), 2014/12/19 21:50:46]

Content-Length is read by the HttpStreamParser. We never directly examine it in
HttpProxyClientSocket.

[Ryan Hamilton, 2014/12/19 21:53:45]

Ah, I missed the last part. Ok, makes sense.

+  CopyHeaderValues(old_headers, new_headers, "Proxy-Authenticate");
+
+  response->headers = new_headers;
+  return true;
+}
+
+// static
+bool ProxyClientSocket::SanitizeProxyRedirect(HttpResponseInfo* response) {
   DCHECK(response && response->headers.get());
 
   std::string location;
   if (!response->headers->IsRedirect(&location))
     return false;
 
-  // Return minimal headers; set "Content-length: 0" to ignore response body.
-  std::string fake_response_headers =
-      base::StringPrintf("HTTP/1.0 302 Found\n"
-                         "Location: %s\n"
-                         "Content-length: 0\n"
-                         "Connection: close\n"
-                         "\n",
-                         location.c_str());
+  // Return minimal headers; set "Content-Length: 0" to ignore response body.
+  std::string fake_response_headers = base::StringPrintf(
+      "HTTP/1.0 302 Found\n"
+      "Location: %s\n"
+      "Content-Length: 0\n"
+      "Connection: close\n"
+      "\n",
+      location.c_str());
   std::string raw_headers =
       HttpUtil::AssembleRawHeaders(fake_response_headers.data(),
                                    fake_response_headers.length());