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 #endif
  66   }
  67
  68   ~OpenSSLInitSingleton() {
  69     CRYPTO_set_locking_callback(NULL);
  70     EVP_cleanup();
  71     ERR_free_strings();
  72   }
  73
  74   static void LockingCallback(int mode, int n, const char* file, int line) {
  75     OpenSSLInitSingleton::GetInstance()->OnLockingCallback(mode, n, file, line);
  76   }
  77
  78   void OnLockingCallback(int mode, int n, const char* file, int line) {
  79     CHECK_LT(static_cast<size_t>(n), locks_.size());
  80     if (mode & CRYPTO_LOCK)
  81       locks_[n]->Acquire();
  82     else
  83       locks_[n]->Release();
  84   }
  85
  86   // These locks are used and managed by OpenSSL via LockingCallback().
  87   ScopedVector<base::Lock> locks_;
  88
  89   DISALLOW_COPY_AND_ASSIGN(OpenSSLInitSingleton);
  90 };
  91
  92 // Callback routine for OpenSSL to print error messages. |str| is a
  93 // NULL-terminated string of length |len| containing diagnostic information
  94 // such as the library, function and reason for the error, the file and line
  95 // where the error originated, plus potentially any context-specific
  96 // information about the error. |context| contains a pointer to user-supplied
  97 // data, which is currently unused.
  98 // If this callback returns a value <= 0, OpenSSL will stop processing the
  99 // error queue and return, otherwise it will continue calling this function
 100 // until all errors have been removed from the queue.
 101 int OpenSSLErrorCallback(const char* str, size_t len, void* context) {
 102   DVLOG(1) << "\t" << base::StringPiece(str, len);
 103   return 1;
 104 }
 105
 106 }  // namespace
 107
 108 void EnsureOpenSSLInit() {
 109   (void)OpenSSLInitSingleton::GetInstance();
 110 }
 111
 112 void ClearOpenSSLERRStack(const tracked_objects::Location& location) {
 113   if (logging::DEBUG_MODE && VLOG_IS_ON(1)) {
 114     int error_num = ERR_peek_error();
 115     if (error_num == 0)
 116       return;
 117
 118     std::string message;
 119     location.Write(true, true, &message);
 120     DVLOG(1) << "OpenSSL ERR_get_error stack from " << message;
 121     ERR_print_errors_cb(&OpenSSLErrorCallback, NULL);
 122   } else {
 123     ERR_clear_error();
 124   }
 125 }
 126
 127 }  // namespace crypto