net: don't crash when processing a certificate with an unknown public key.

net/base/x509_certificate_openssl.cc

 // Copyright (c) 2012 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/base/x509_certificate.h"
 
 #include <openssl/asn1.h>
 #include <openssl/crypto.h>
 #include <openssl/obj_mac.h>
 #include <openssl/pem.h>
@@ skipping 422 matching lines @@
 
   return pickle->WriteData(
       reinterpret_cast<const char*>(der_cache.data),
       der_cache.data_length);
 }
 
 // static
 void X509Certificate::GetPublicKeyInfo(OSCertHandle cert_handle,
                                        size_t* size_bits,
                                        PublicKeyType* type) {
+  *type = kPublicKeyTypeUnknown;
+  *size_bits = 0;
+
   crypto::ScopedOpenSSL<EVP_PKEY, EVP_PKEY_free> scoped_key(
       X509_get_pubkey(cert_handle));
+  if (!scoped_key.get())
+    return;
+
   CHECK(scoped_key.get());
   EVP_PKEY* key = scoped_key.get();
 
   switch (key->type) {
     case EVP_PKEY_RSA:
       *type = kPublicKeyTypeRSA;
       *size_bits = EVP_PKEY_size(key) * 8;
       break;
     case EVP_PKEY_DSA:
       *type = kPublicKeyTypeDSA;
       *size_bits = EVP_PKEY_size(key) * 8;
       break;
     case EVP_PKEY_EC:
       *type = kPublicKeyTypeECDSA;
       *size_bits = EVP_PKEY_size(key);
       break;
     case EVP_PKEY_DH:
       *type = kPublicKeyTypeDH;
       *size_bits = EVP_PKEY_size(key) * 8;
       break;
-    default:
-      *type = kPublicKeyTypeUnknown;
-      *size_bits = 0;
-      break;
   }
 }
 
 }  // namespace net