Differential D7608 Diff 23902 src/secp256k1/src/scratch_impl.h

Changeset View

Standalone View

src/secp256k1/src/scratch_impl.h

/**********************************************************************		/**********************************************************************
* Copyright (c) 2017 Andrew Poelstra *		* Copyright (c) 2017 Andrew Poelstra *
* Distributed under the MIT software license, see the accompanying *		* Distributed under the MIT software license, see the accompanying *
* file COPYING or http://www.opensource.org/licenses/mit-license.php.*		* file COPYING or http://www.opensource.org/licenses/mit-license.php.*
**********************************************************************/		**********************************************************************/

#ifndef _SECP256K1_SCRATCH_IMPL_H_		#ifndef _SECP256K1_SCRATCH_IMPL_H_
#define _SECP256K1_SCRATCH_IMPL_H_		#define _SECP256K1_SCRATCH_IMPL_H_

#include "util.h"		#include "util.h"
#include "scratch.h"		#include "scratch.h"

static secp256k1_scratch* secp256k1_scratch_create(const secp256k1_callback* error_callback, size_t size) {		static secp256k1_scratch* secp256k1_scratch_create(const secp256k1_callback* error_callback, size_t size) {
const size_t base_alloc = ((sizeof(secp256k1_scratch) + ALIGNMENT - 1) / ALIGNMENT) * ALIGNMENT;		const size_t base_alloc = ROUND_TO_ALIGN(sizeof(secp256k1_scratch));
void *alloc = checked_malloc(error_callback, base_alloc + size);		void *alloc = checked_malloc(error_callback, base_alloc + size);
secp256k1_scratch* ret = (secp256k1_scratch *)alloc;		secp256k1_scratch* ret = (secp256k1_scratch *)alloc;
if (ret != NULL) {		if (ret != NULL) {
memset(ret, 0, sizeof(*ret));		memset(ret, 0, sizeof(*ret));
memcpy(ret->magic, "scratch", 8);		memcpy(ret->magic, "scratch", 8);
ret->data = (void ) ((char ) alloc + base_alloc);		ret->data = (void ) ((char ) alloc + base_alloc);
ret->max_size = size;		ret->max_size = size;
}		}
Show All 32 Lines	static void secp256k1_scratch_apply_checkpoint(const secp256k1_callback* error_callback, secp256k1_scratch* scratch, size_t checkpoint) {
scratch->alloc_size = checkpoint;		scratch->alloc_size = checkpoint;
}		}

static size_t secp256k1_scratch_max_allocation(const secp256k1_callback* error_callback, const secp256k1_scratch* scratch, size_t objects) {		static size_t secp256k1_scratch_max_allocation(const secp256k1_callback* error_callback, const secp256k1_scratch* scratch, size_t objects) {
if (memcmp(scratch->magic, "scratch", 8) != 0) {		if (memcmp(scratch->magic, "scratch", 8) != 0) {
secp256k1_callback_call(error_callback, "invalid scratch space");		secp256k1_callback_call(error_callback, "invalid scratch space");
return 0;		return 0;
}		}
		/* Ensure that multiplication will not wrap around */
		if (ALIGNMENT > 1 && objects > SIZE_MAX/(ALIGNMENT - 1)) {
		return 0;
		}
if (scratch->max_size - scratch->alloc_size <= objects * (ALIGNMENT - 1)) {		if (scratch->max_size - scratch->alloc_size <= objects * (ALIGNMENT - 1)) {
return 0;		return 0;
}		}
return scratch->max_size - scratch->alloc_size - objects * (ALIGNMENT - 1);		return scratch->max_size - scratch->alloc_size - objects * (ALIGNMENT - 1);
}		}

static void secp256k1_scratch_alloc(const secp256k1_callback error_callback, secp256k1_scratch* scratch, size_t size) {		static void secp256k1_scratch_alloc(const secp256k1_callback error_callback, secp256k1_scratch* scratch, size_t size) {
void *ret;		void *ret;
size = ROUND_TO_ALIGN(size);		size_t rounded_size;

		rounded_size = ROUND_TO_ALIGN(size);
		/* Check that rounding did not wrap around */
		if (rounded_size < size) {
		return NULL;
		}
		size = rounded_size;

if (memcmp(scratch->magic, "scratch", 8) != 0) {		if (memcmp(scratch->magic, "scratch", 8) != 0) {
secp256k1_callback_call(error_callback, "invalid scratch space");		secp256k1_callback_call(error_callback, "invalid scratch space");
return NULL;		return NULL;
}		}

if (size > scratch->max_size - scratch->alloc_size) {		if (size > scratch->max_size - scratch->alloc_size) {
return NULL;		return NULL;
Show All 9 Lines