Disable Poly1305 code only on bad chips.

crypto/openssl_util.cc

 // Copyright (c) 2011 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 "crypto/openssl_util.h"
 
 #include <openssl/err.h>
 #include <openssl/ssl.h>
 #include <openssl/cpu.h>
 
 #include "base/logging.h"
 #include "base/memory/scoped_vector.h"
 #include "base/memory/singleton.h"
 #include "base/strings/string_piece.h"
 #include "base/synchronization/lock.h"
 #include "build/build_config.h"
 
 #if defined(OS_ANDROID) && defined(ARCH_CPU_ARMEL)
 #include <cpu-features.h>
+#include "base/cpu.h"
 #endif
 
 namespace crypto {
 
 namespace {
 
 void CurrentThreadId(CRYPTO_THREADID* id) {
   CRYPTO_THREADID_set_numeric(
       id, static_cast<unsigned long>(base::PlatformThread::CurrentId()));
 }
@@ skipping 25 matching lines @@
     for (int i = 0; i < num_locks; ++i)
       locks_.push_back(new base::Lock());
     CRYPTO_set_locking_callback(LockingCallback);
     CRYPTO_THREADID_set_callback(CurrentThreadId);
 
 #if defined(OS_ANDROID) && defined(ARCH_CPU_ARMEL)
     const bool has_neon =
         (android_getCpuFeatures() & ANDROID_CPU_ARM_FEATURE_NEON) != 0;
     if (has_neon)
       CRYPTO_set_NEON_capable(1);
-    // In all cases, currently, mark the NEON unit as broken because some
-    // phones can't execute the Poly1305 code correctly. See
-    // https://code.google.com/p/chromium/issues/detail?id=341598
-    CRYPTO_set_NEON_functional(0);
+    // See https://code.google.com/p/chromium/issues/detail?id=341598
+    base::CPU cpu;
+    CRYPTO_set_NEON_functional(!cpu.has_broken_neon());
 #endif
   }
 
   ~OpenSSLInitSingleton() {
     CRYPTO_set_locking_callback(NULL);
     EVP_cleanup();
     ERR_free_strings();
   }
 
   static void LockingCallback(int mode, int n, const char* file, int line) {
@@ skipping 43 matching lines @@
     std::string message;
     location.Write(true, true, &message);
     DVLOG(1) << "OpenSSL ERR_get_error stack from " << message;
     ERR_print_errors_cb(&OpenSSLErrorCallback, NULL);
   } else {
     ERR_clear_error();
   }
 }
 
 }  // namespace crypto