/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*- */

/* egg-secure-memory.h - library for allocating memory that is non-pageable

   Copyright (C) 2007 Stefan Walter

   The Gnome Keyring Library is free software; you can redistribute it and/or

   modify it under the terms of the GNU Library General Public License as

   published by the Free Software Foundation; either version 2 of the

   License, or (at your option) any later version.

   The Gnome Keyring Library is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public

   License along with the Gnome Library; see the file COPYING.LIB.  If not,

   see <http://www.gnu.org/licenses/>.

   Author: Stef Walter <stef@memberwebs.com>

*/

#ifndef EGG_SECURE_MEMORY_H

#define EGG_SECURE_MEMORY_H

#include <stdlib.h>

/* -------------------------------------------------------------------

 * Low Level Secure Memory

 *

 * IMPORTANT: This is pure vanila standard C, no glib. We need this

 * because certain consumers of this protocol need to be built

 * without linking in any special libraries. ie: the PKCS#11 module.

 *

 * Thread locking

 *

 * In order to use these functions in a module the following functions

 * must be defined somewhere, and provide appropriate locking for

 * secure memory between threads:

 */

typedef struct {

	void       (* lock)        (void);

	void       (* unlock)      (void);

	void *     (* fallback)    (void *pointer,

	                            size_t length);

	void *        pool_data;

	const char *  pool_version;

} egg_secure_glob;

#define EGG_SECURE_POOL_VER_STR             "1.0"

#define EGG_SECURE_GLOBALS SECMEM_pool_data_v1_0

#define EGG_SECURE_DEFINE_GLOBALS(lock, unlock, fallback) \

	egg_secure_glob EGG_SECURE_GLOBALS = { \

		lock, unlock, fallback, NULL, EGG_SECURE_POOL_VER_STR };

#define EGG_SECURE_DEFINE_GLIB_GLOBALS() \

	static GMutex memory_mutex = { 0, }; \

	static void egg_memory_lock (void) \

		{ g_mutex_lock (&memory_mutex); } \

	static void egg_memory_unlock (void) \

		{ g_mutex_unlock (&memory_mutex); } \

	EGG_SECURE_DEFINE_GLOBALS (egg_memory_lock, egg_memory_unlock, g_realloc);

extern egg_secure_glob EGG_SECURE_GLOBALS;

/*

 * Main functionality

 *

 * Allocations return NULL on failure.

 */

#define EGG_SECURE_USE_FALLBACK     0x0001

#define EGG_SECURE_DECLARE(tag) \

	static inline void* egg_secure_alloc (size_t length) { \

		return egg_secure_alloc_full (G_STRINGIFY (tag), length, EGG_SECURE_USE_FALLBACK); \

	} \

	static inline void* egg_secure_realloc (void *p, size_t length) { \

		return egg_secure_realloc_full (G_STRINGIFY (tag), p, length, EGG_SECURE_USE_FALLBACK); \

	} \

	static inline void* egg_secure_strdup (const char *str) { \

		return egg_secure_strdup_full (G_STRINGIFY (tag), str, EGG_SECURE_USE_FALLBACK); \

	} \

	static inline void* egg_secure_strndup (const char *str, size_t length) { \

		return egg_secure_strndup_full (G_STRINGIFY (tag), str, length, EGG_SECURE_USE_FALLBACK); \

	}

void*  egg_secure_alloc_full   (const char *tag, size_t length, int options);

void*  egg_secure_realloc_full (const char *tag, void *p, size_t length, int options);

void   egg_secure_free         (void* p);

void   egg_secure_free_full    (void* p, int fallback);

void   egg_secure_clear        (void *p, size_t length);

int    egg_secure_check        (const void* p);

void   egg_secure_validate     (void);

char*  egg_secure_strdup_full  (const char *tag, const char *str, int options);

char*  egg_secure_strndup_full (const char *tag, const char *str, size_t length, int options);

void   egg_secure_strclear     (char *str);

void   egg_secure_strfree      (char *str);

typedef struct {

	const char *tag;

	size_t request_length;

	size_t block_length;

} egg_secure_rec;

egg_secure_rec *   egg_secure_records    (unsigned int *count);

#endif /* EGG_SECURE_MEMORY_H */