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