| Index: crypto/openssl_util.h
|
| diff --git a/crypto/openssl_util.h b/crypto/openssl_util.h
|
| new file mode 100644
|
| index 0000000000000000000000000000000000000000..2743883dc17b4dadcdc4402bb2c59ce64095c493
|
| --- /dev/null
|
| +++ b/crypto/openssl_util.h
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| @@ -0,0 +1,90 @@
|
| +// Copyright (c) 2012 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 CRYPTO_OPENSSL_UTIL_H_
|
| +#define CRYPTO_OPENSSL_UTIL_H_
|
| +
|
| +#include "base/basictypes.h"
|
| +#include "base/location.h"
|
| +#include "crypto/crypto_export.h"
|
| +
|
| +namespace crypto {
|
| +
|
| +// 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 its 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 though it is safe and cheap to call this
|
| +// multiple times.
|
| +// This function is thread-safe, and OpenSSL will only ever be initialized once.
|
| +// OpenSSL will be properly shut down on program exit.
|
| +void CRYPTO_EXPORT 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 CRYPTO_EXPORT 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 crypto
|
| +
|
| +#endif // CRYPTO_OPENSSL_UTIL_H_
|
|
|