[NOT FOR REVIEW] Ensure contributory behaviour for Web Push encryption.

components/gcm_driver/crypto/p256_key_util_openssl.cc

 // Copyright 2015 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/gcm_driver/crypto/p256_key_util.h"
 
 #include <stdint.h>
 
 #include <openssl/ec.h>
 #include <openssl/ecdh.h>
 #include <openssl/evp.h>
 
+#include "base/base64url.h"
+
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/string_util.h"
 #include "crypto/ec_private_key.h"
 #include "crypto/scoped_openssl_types.h"
 
 namespace gcm {
 
 namespace {
 
@@ skipping 15 matching lines @@
               private_key.data(), private_key.data() + private_key.size()),
           std::vector<uint8_t>(
               public_key_x509.data(),
               public_key_x509.data() + public_key_x509.size())));
 
   if (!local_key_pair) {
     DLOG(ERROR) << "Unable to create the local key pair.";
     return false;
   }
 
+  std::vector<uint8_t> pubkey;
+  local_key_pair->ExportPublicKey(&pubkey);
+
+  std::string res(reinterpret_cast<char*>(pubkey.data()), pubkey.size());
+
+  std::string b;
+  base::Base64UrlEncode(res, base::Base64UrlEncodePolicy::OMIT_PADDING, &b);
+
+  LOG(INFO) << "x509 key: [" << b << "]";
+
   crypto::ScopedEC_KEY ec_private_key(
       EVP_PKEY_get1_EC_KEY(local_key_pair->key()));
 
   if (!ec_private_key || !EC_KEY_check_key(ec_private_key.get())) {
     DLOG(ERROR) << "The private key is invalid.";
     return false;
   }
 
   crypto::ScopedEC_POINT point(
       EC_POINT_new(EC_KEY_get0_group(ec_private_key.get())));
@@ skipping 12 matching lines @@
                        ec_private_key.get(), nullptr) != sizeof(result)) {
     DLOG(ERROR) << "Unable to compute the ECDH shared secret.";
     return false;
   }
 
   out_shared_secret->assign(reinterpret_cast<char*>(result), sizeof(result));
   return true;
 }
 
 }  // namespace gcm