crypto/openssl_util.cc

   1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "crypto/openssl_util.h"
   6
   7 #include <openssl/err.h>
   8 #include <openssl/ssl.h>
   9 #include <openssl/cpu.h>
  10
  11 #include "base/logging.h"
  12 #include "base/memory/scoped_vector.h"
  13 #include "base/memory/singleton.h"
  14 #include "base/strings/string_piece.h"
  15 #include "base/synchronization/lock.h"
  16 #include "build/build_config.h"
  17
  18 #if defined(OS_ANDROID) && defined(ARCH_CPU_ARMEL)
  19 #include <cpu-features.h>
  20 #endif
  21
  22 namespace crypto {
  23
  24 namespace {
  25
  26 void CurrentThreadId(CRYPTO_THREADID* id) {
  27   CRYPTO_THREADID_set_numeric(
  28       id, static_cast<unsigned long>(base::PlatformThread::CurrentId()));
  29 }
  30
  31 // Singleton for initializing and cleaning up the OpenSSL library.
  32 class OpenSSLInitSingleton {
  33  public:
  34   static OpenSSLInitSingleton* GetInstance() {
  35     // We allow the SSL environment to leak for multiple reasons:
  36     //   -  it is used from a non-joinable worker thread that is not stopped on
  37     //      shutdown, hence may still be using OpenSSL library after the AtExit
  38     //      runner has completed.
  39     //   -  There are other OpenSSL related singletons (e.g. the client socket
  40     //      context) who's cleanup depends on the global environment here, but
  41     //      we can't control the order the AtExit handlers will run in so
  42     //      allowing the global environment to leak at least ensures it is
  43     //      available for those other singletons to reliably cleanup.
  44     return Singleton<OpenSSLInitSingleton,
  45                LeakySingletonTraits<OpenSSLInitSingleton> >::get();
  46   }
  47  private:
  48   friend struct DefaultSingletonTraits<OpenSSLInitSingleton>;
  49   OpenSSLInitSingleton() {
  50     SSL_load_error_strings();
  51     SSL_library_init();
  52     OpenSSL_add_all_algorithms();
  53     int num_locks = CRYPTO_num_locks();
  54     locks_.reserve(num_locks);
  55     for (int i = 0; i < num_locks; ++i)
  56       locks_.push_back(new base::Lock());
  57     CRYPTO_set_locking_callback(LockingCallback);
  58     CRYPTO_THREADID_set_callback(CurrentThreadId);
  59
  60 #if defined(OS_ANDROID) && defined(ARCH_CPU_ARMEL)
  61     const bool has_neon =
  62         (android_getCpuFeatures() & ANDROID_CPU_ARM_FEATURE_NEON) != 0;
  63     if (has_neon)
  64       CRYPTO_set_NEON_capable(1);
  65     // In all cases, currently, mark the NEON unit as broken because some
  66     // phones can't execute the Poly1305 code correctly. See
  67     // https://code.google.com/p/chromium/issues/detail?id=341598
  68     CRYPTO_set_NEON_functional(0);
  69 #endif
  70   }
  71
  72   ~OpenSSLInitSingleton() {
  73     CRYPTO_set_locking_callback(NULL);
  74     EVP_cleanup();
  75     ERR_free_strings();
  76   }
  77
  78   static void LockingCallback(int mode, int n, const char* file, int line) {
  79     OpenSSLInitSingleton::GetInstance()->OnLockingCallback(mode, n, file, line);
  80   }
  81
  82   void OnLockingCallback(int mode, int n, const char* file, int line) {
  83     CHECK_LT(static_cast<size_t>(n), locks_.size());
  84     if (mode & CRYPTO_LOCK)
  85       locks_[n]->Acquire();
  86     else
  87       locks_[n]->Release();
  88   }
  89
  90   // These locks are used and managed by OpenSSL via LockingCallback().
  91   ScopedVector<base::Lock> locks_;
  92
  93   DISALLOW_COPY_AND_ASSIGN(OpenSSLInitSingleton);
  94 };
  95
  96 // Callback routine for OpenSSL to print error messages. |str| is a
  97 // NULL-terminated string of length |len| containing diagnostic information
  98 // such as the library, function and reason for the error, the file and line
  99 // where the error originated, plus potentially any context-specific
 100 // information about the error. |context| contains a pointer to user-supplied
 101 // data, which is currently unused.
 102 // If this callback returns a value <= 0, OpenSSL will stop processing the
 103 // error queue and return, otherwise it will continue calling this function
 104 // until all errors have been removed from the queue.
 105 int OpenSSLErrorCallback(const char* str, size_t len, void* context) {
 106   DVLOG(1) << "\t" << base::StringPiece(str, len);
 107   return 1;
 108 }
 109
 110 }  // namespace
 111
 112 void EnsureOpenSSLInit() {
 113   (void)OpenSSLInitSingleton::GetInstance();
 114 }
 115
 116 void ClearOpenSSLERRStack(const tracked_objects::Location& location) {
 117   if (logging::DEBUG_MODE && VLOG_IS_ON(1)) {
 118     int error_num = ERR_peek_error();
 119     if (error_num == 0)
 120       return;
 121
 122     std::string message;
 123     location.Write(true, true, &message);
 124     DVLOG(1) << "OpenSSL ERR_get_error stack from " << message;
 125     ERR_print_errors_cb(&OpenSSLErrorCallback, NULL);
 126   } else {
 127     ERR_clear_error();
 128   }
 129 }
 130
 131 }  // namespace crypto