Move crypto files out of base, to a top level directory.

base/openssl_util.h

-// Copyright (c) 2010 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.
-
-#ifndef BASE_OPENSSL_UTIL_H_
-#define BASE_OPENSSL_UTIL_H_
-#pragma once
-
-#include "base/basictypes.h"
-#include "base/tracked.h"
-
-namespace base {
-
-// A helper class that takes care of destroying OpenSSL objects when it goes out
-// of scope.
-template <typename T, void (*destructor)(T*)>
-class ScopedOpenSSL {
- public:
-  ScopedOpenSSL() : ptr_(NULL) { }
-  explicit ScopedOpenSSL(T* ptr) : ptr_(ptr) { }
-  ~ScopedOpenSSL() {
-    reset(NULL);
-  }
-
-  T* get() const { return ptr_; }
-  void reset(T* ptr) {
-    if (ptr != ptr_) {
-      if (ptr_) (*destructor)(ptr_);
-      ptr_ = ptr;
-    }
-  }
-
- private:
-  T* ptr_;
-
-  DISALLOW_COPY_AND_ASSIGN(ScopedOpenSSL);
-};
-
-// Provides a buffer of at least MIN_SIZE bytes, for use when calling OpenSSL's
-// SHA256, HMAC, etc functions, adapting the buffer sizing rules to meet those
-// of the our base wrapper APIs.
-// This allows the library to write directly to the caller's buffer if it is of
-// sufficient size, but if not it will write to temporary |min_sized_buffer_|
-// of required size and then its content is automatically copied out on
-// destruction, with truncation as appropriate.
-template<int MIN_SIZE>
-class ScopedOpenSSLSafeSizeBuffer {
- public:
-  ScopedOpenSSLSafeSizeBuffer(unsigned char* output, size_t output_len)
-      : output_(output),
-        output_len_(output_len) {
-  }
-
-  ~ScopedOpenSSLSafeSizeBuffer() {
-    if (output_len_ < MIN_SIZE) {
-      // Copy the temporary buffer out, truncating as needed.
-      memcpy(output_, min_sized_buffer_, output_len_);
-    }
-    // else... any writing already happened directly into |output_|.
-  }
-
-  unsigned char* safe_buffer() {
-    return output_len_ < MIN_SIZE ? min_sized_buffer_ : output_;
-  }
-
- private:
-  // Pointer to the caller's data area and it's associated size, where data
-  // written via safe_buffer() will [eventually] end up.
-  unsigned char* output_;
-  size_t output_len_;
-
-  // Temporary buffer writen into in the case where the caller's
-  // buffer is not of sufficient size.
-  unsigned char min_sized_buffer_[MIN_SIZE];
-
-  DISALLOW_COPY_AND_ASSIGN(ScopedOpenSSLSafeSizeBuffer);
-};
-
-// Initialize OpenSSL if it isn't already initialized. This must be called
-// before any other OpenSSL functions.
-// This function is thread-safe, and OpenSSL will only ever be initialized once.
-// OpenSSL will be properly shut down on program exit.
-void EnsureOpenSSLInit();
-
-// Drains the OpenSSL ERR_get_error stack. On a debug build the error codes
-// are send to VLOG(1), on a release build they are disregarded. In most
-// cases you should pass FROM_HERE as the |location|.
-void ClearOpenSSLERRStack(const tracked_objects::Location& location);
-
-// Place an instance of this class on the call stack to automatically clear
-// the OpenSSL error stack on function exit.
-class OpenSSLErrStackTracer {
- public:
-  // Pass FROM_HERE as |location|, to help track the source of OpenSSL error
-  // messages. Note any diagnostic emitted will be tagged with the location of
-  // the constructor call as it's not possible to trace a destructor's callsite.
-  explicit OpenSSLErrStackTracer(const tracked_objects::Location& location)
-      : location_(location) {
-    EnsureOpenSSLInit();
-  }
-  ~OpenSSLErrStackTracer() {
-    ClearOpenSSLERRStack(location_);
-  }
-
- private:
-  const tracked_objects::Location location_;
-
-  DISALLOW_IMPLICIT_CONSTRUCTORS(OpenSSLErrStackTracer);
-};
-
-}  // namespace base
-
-#endif  // BASE_OPENSSL_UTIL_H_