components: add wifi_sync component

components/wifi_sync/wifi_credential.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/wifi_sync/wifi_credential.h"
+
+#include <limits>
+#include <string>
+
+#include "base/logging.h"
+#include "base/strings/string_number_conversions.h"
+#include "base/strings/stringprintf.h"
+
+namespace wifi_sync {
+
+WifiCredential::WifiCredential(
+    const std::vector<unsigned char>& ssid,
+    WifiSecurityClass security_class,
+    const std::string& passphrase)
+    : ssid_(ssid),
+      security_class_(security_class),
+      passphrase_(passphrase) {
+}
+
+WifiCredential::~WifiCredential() {
+  // Nothing special to do.

[erikwright (departed), 2014/12/08 21:21:36]

remove comment. The reasons for an empty destructor definition are well-known.

[mukesh agrawal, 2014/12/09 01:41:11]

Done.

+}
+
+std::string WifiCredential::ToString() const {
+  DCHECK(ssid_.size() <= std::numeric_limits<size_t>::max() / 2);

[erikwright (departed), 2014/12/08 21:21:36]

Is there not some more reasonable upper limit on an SSID?

Note that I can come up with some SSIDs that would pass this test but still
cause the generated string to exceed size_t chars (because of the boiler-plate
in the string)...

Also, this doesn't actually protect against exploit attempts (if the SSID could
actually be made this long by an attacker) since it's a DCHECK.

I would just remove it, or, if it is meant to be a protection, rethink it.

[mukesh agrawal, 2014/12/09 01:41:11]

Done.

You're quite right on all three counts. After some thought, I've concluded that
the length checking should be done by whoever creates the WifiCredential. E.g.,
when we read data from sync, or the local network configuration back-end.

+  return base::StringPrintf(
+      "[SSID (hex): %s, SecurityClass: %d]",
+      base::HexEncode(ssid_.data(), ssid_.size()).c_str(),
+      security_class_);  // Passphrase deliberately omitted.
+}
+
+// static
+bool WifiCredential::IsLessThan(
+    const WifiCredential& a, const WifiCredential& b) {
+  return a.ssid_ < b.ssid_ ||
+      a.security_class_< b.security_class_ ||
+      a.passphrase_ < b.passphrase_;
+}
+
+// static
+WifiCredential::CredentialSet WifiCredential::MakeSet() {
+  return CredentialSet(WifiCredential::IsLessThan);
+}
+
+}  // namespace wifi_sync