Componentize renderer side of DNS prefetching.

components/dns_prefetch/common/prefetch_messages.cc

+// Copyright 2014 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 "components/dns_prefetch/common/prefetch_messages.h"
+
+#include "base/strings/string_number_conversions.h"
+#include "components/dns_prefetch/common/prefetch_common.h"
+
+namespace IPC {
+
+void ParamTraits<dns_prefetch::LookupRequest>::Write(
+    Message* m, const dns_prefetch::LookupRequest& request) {
+  IPC::WriteParam(m, request.hostname_list);
+}
+
+bool ParamTraits<dns_prefetch::LookupRequest>::Read(
+    const Message* m,
+    PickleIterator* iter,
+    dns_prefetch::LookupRequest* request) {
+  // Verify the hostname limits after deserialization success.
+  if (IPC::ReadParam(m, iter, &request->hostname_list)) {
+    dns_prefetch::NameList& hostnames = request->hostname_list;
+    if (hostnames.size() > dns_prefetch::kMaxDnsHostnamesPerRequest)
+      return false;
+
+    for (const auto& hostname : hostnames) {
+      if (hostname.length() > dns_prefetch::kMaxDnsHostnameLength)

[palmer, 2014/10/31 18:46:23]

There's more to a hostname's validity than its length. Max length, max length
per label, max # of labels, valid characters.

Ultimately, this should be enforced by the type system: a class Hostname whose
constructor enforces the RFC.

+        return false;
+    }
+  }
+  return true;
+}
+
+void ParamTraits<dns_prefetch::LookupRequest>::Log(
+    const dns_prefetch::LookupRequest& p, std::string* l) {
+  l->append("<dns_prefetch::LookupRequest: ");
+  l->append(base::UintToString(p.hostname_list.size()));
+  l->append(" hostnames>");
+}
+
+}  // namespace IPC