Implement TLS client auth in the OS X OpenSSL port.

net/ssl/openssl_client_key_store.cc

 // Copyright (c) 2013 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/ssl/openssl_client_key_store.h"
 
 #include <openssl/evp.h>
 #include <openssl/x509.h>
 
 #include "base/memory/scoped_ptr.h"
@@ skipping 89 matching lines @@
 
   // Get public key from certificate.
   crypto::ScopedEVP_PKEY pub_key(GetOpenSSLPublicKey(client_cert));
   if (!pub_key.get())
     return false;
 
   AddKeyPair(pub_key.get(), private_key);
   return true;
 }
 
-bool OpenSSLClientKeyStore::FetchClientCertPrivateKey(
-    const X509Certificate* client_cert,
-    crypto::ScopedEVP_PKEY* private_key) {
+crypto::ScopedEVP_PKEY OpenSSLClientKeyStore::FetchClientCertPrivateKey(
+    const X509Certificate* client_cert) {
   if (!client_cert)
-    return false;
+    return crypto::ScopedEVP_PKEY();

[Ryan Sleevi, 2014/07/24 19:13:02]

Random comment: This code prevents NRVO, because it's not using a named
variable.

See http://msdn.microsoft.com/en-us/library/ms364057(v=vs.80).aspx for a bit of
the documentation and limits (in an MSVC context, but also applies largely to
Clang and GCC)

However, because of our move emulation, using a named ScopedEVP_PKEY would
require us to use .Pass() at each return point, which would also violate NRVO.

Turns out, there's no "guaranteed" way to ensure NRVO with a scoped-ptr return
value. Didn't realize it until this code though.

[davidben, 2014/07/24 21:02:25]

(Tangentially, I wish we could spell those lines return NULL or return nullptr.
I suppose C++11 will fix that one.)

 
   crypto::ScopedEVP_PKEY pub_key(GetOpenSSLPublicKey(client_cert));
   if (!pub_key.get())
-    return false;
+    return crypto::ScopedEVP_PKEY();
 
   int index = FindKeyPairIndex(pub_key.get());
   if (index < 0)
-    return false;
+    return crypto::ScopedEVP_PKEY();
 
-  private_key->reset(CopyEVP_PKEY(pairs_[index].private_key));
-  return true;
+  return crypto::ScopedEVP_PKEY(CopyEVP_PKEY(pairs_[index].private_key));
 }
 
 void OpenSSLClientKeyStore::Flush() {
   pairs_.clear();
 }
 
 OpenSSLClientKeyStore* OpenSSLClientKeyStore::GetInstance() {
   return Singleton<OpenSSLClientKeyStore>::get();
 }
 
 }  // namespace net