-/* crypto/bn/bn_ctx.c */
-/* Written by Ulf Moeller for the OpenSSL project. */
-/* ====================================================================
- * Copyright (c) 1998-2004 The OpenSSL Project. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in
- * the documentation and/or other materials provided with the
- * distribution.
- *
- * 3. All advertising materials mentioning features or use of this
- * software must display the following acknowledgment:
- * "This product includes software developed by the OpenSSL Project
- * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
- *
- * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
- * endorse or promote products derived from this software without
- * prior written permission. For written permission, please contact
- * openssl-core@openssl.org.
- *
- * 5. Products derived from this software may not be called "OpenSSL"
- * nor may "OpenSSL" appear in their names without prior written
- * permission of the OpenSSL Project.
- *
- * 6. Redistributions of any form whatsoever must retain the following
- * acknowledgment:
- * "This product includes software developed by the OpenSSL Project
- * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
- *
- * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
- * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
- * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
- * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
- * OF THE POSSIBILITY OF SUCH DAMAGE.
- * ====================================================================
- *
- * This product includes cryptographic software written by Eric Young
- * (eay@cryptsoft.com). This product includes software written by Tim
- * Hudson (tjh@cryptsoft.com).
+/*
+ * Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.
*
+ * Licensed under the OpenSSL license (the "License"). You may not use
+ * this file except in compliance with the License. You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
*/
-#if !defined(BN_CTX_DEBUG) && !defined(BN_DEBUG)
-#ifndef NDEBUG
-#define NDEBUG
-#endif
-#endif
-
-#include <stdio.h>
-#include <assert.h>
-
-#include "cryptlib.h"
+#include "internal/cryptlib.h"
#include "bn_lcl.h"
-/* TODO list
+/*-
+ * TODO list
*
* 1. Check a bunch of "(words+1)" type hacks in various bignum functions and
* check they can be safely removed.
*/
/* How many bignums are in each "pool item"; */
-#define BN_CTX_POOL_SIZE 16
+#define BN_CTX_POOL_SIZE 16
/* The stack frame info is resizing, set a first-time expansion size; */
-#define BN_CTX_START_FRAMES 32
+#define BN_CTX_START_FRAMES 32
/***********/
/* BN_POOL */
/***********/
/* A bundle of bignums that can be linked with other bundles */
-typedef struct bignum_pool_item
- {
- /* The bignum values */
- BIGNUM vals[BN_CTX_POOL_SIZE];
- /* Linked-list admin */
- struct bignum_pool_item *prev, *next;
- } BN_POOL_ITEM;
+typedef struct bignum_pool_item {
+ /* The bignum values */
+ BIGNUM vals[BN_CTX_POOL_SIZE];
+ /* Linked-list admin */
+ struct bignum_pool_item *prev, *next;
+} BN_POOL_ITEM;
/* A linked-list of bignums grouped in bundles */
-typedef struct bignum_pool
- {
- /* Linked-list admin */
- BN_POOL_ITEM *head, *current, *tail;
- /* Stack depth and allocation size */
- unsigned used, size;
- } BN_POOL;
-static void BN_POOL_init(BN_POOL *);
-static void BN_POOL_finish(BN_POOL *);
-#ifndef OPENSSL_NO_DEPRECATED
-static void BN_POOL_reset(BN_POOL *);
-#endif
-static BIGNUM * BN_POOL_get(BN_POOL *);
-static void BN_POOL_release(BN_POOL *, unsigned int);
+typedef struct bignum_pool {
+ /* Linked-list admin */
+ BN_POOL_ITEM *head, *current, *tail;
+ /* Stack depth and allocation size */
+ unsigned used, size;
+} BN_POOL;
+static void BN_POOL_init(BN_POOL *);
+static void BN_POOL_finish(BN_POOL *);
+static BIGNUM *BN_POOL_get(BN_POOL *, int);
+static void BN_POOL_release(BN_POOL *, unsigned int);
/************/
/* BN_STACK */
/************/
/* A wrapper to manage the "stack frames" */
-typedef struct bignum_ctx_stack
- {
- /* Array of indexes into the bignum stack */
- unsigned int *indexes;
- /* Number of stack frames, and the size of the allocated array */
- unsigned int depth, size;
- } BN_STACK;
-static void BN_STACK_init(BN_STACK *);
-static void BN_STACK_finish(BN_STACK *);
-#ifndef OPENSSL_NO_DEPRECATED
-static void BN_STACK_reset(BN_STACK *);
-#endif
-static int BN_STACK_push(BN_STACK *, unsigned int);
-static unsigned int BN_STACK_pop(BN_STACK *);
+typedef struct bignum_ctx_stack {
+ /* Array of indexes into the bignum stack */
+ unsigned int *indexes;
+ /* Number of stack frames, and the size of the allocated array */
+ unsigned int depth, size;
+} BN_STACK;
+static void BN_STACK_init(BN_STACK *);
+static void BN_STACK_finish(BN_STACK *);
+static int BN_STACK_push(BN_STACK *, unsigned int);
+static unsigned int BN_STACK_pop(BN_STACK *);
/**********/
/* BN_CTX */
/**********/
/* The opaque BN_CTX type */
-struct bignum_ctx
- {
- /* The bignum bundles */
- BN_POOL pool;
- /* The "stack frames", if you will */
- BN_STACK stack;
- /* The number of bignums currently assigned */
- unsigned int used;
- /* Depth of stack overflow */
- int err_stack;
- /* Block "gets" until an "end" (compatibility behaviour) */
- int too_many;
- };
+struct bignum_ctx {
+ /* The bignum bundles */
+ BN_POOL pool;
+ /* The "stack frames", if you will */
+ BN_STACK stack;
+ /* The number of bignums currently assigned */
+ unsigned int used;
+ /* Depth of stack overflow */
+ int err_stack;
+ /* Block "gets" until an "end" (compatibility behaviour) */
+ int too_many;
+ /* Flags. */
+ int flags;
+};
/* Enable this to find BN_CTX bugs */
#ifdef BN_CTX_DEBUG
static const char *ctxdbg_cur = NULL;
static void ctxdbg(BN_CTX *ctx)
- {
- unsigned int bnidx = 0, fpidx = 0;
- BN_POOL_ITEM *item = ctx->pool.head;
- BN_STACK *stack = &ctx->stack;
- fprintf(stderr,"(%08x): ", (unsigned int)ctx);
- while(bnidx < ctx->used)
- {
- fprintf(stderr,"%02x ", item->vals[bnidx++ % BN_CTX_POOL_SIZE].dmax);
- if(!(bnidx % BN_CTX_POOL_SIZE))
- item = item->next;
- }
- fprintf(stderr,"\n");
- bnidx = 0;
- fprintf(stderr," : ");
- while(fpidx < stack->depth)
- {
- while(bnidx++ < stack->indexes[fpidx])
- fprintf(stderr," ");
- fprintf(stderr,"^^ ");
- bnidx++;
- fpidx++;
- }
- fprintf(stderr,"\n");
- }
-#define CTXDBG_ENTRY(str, ctx) do { \
- ctxdbg_cur = (str); \
- fprintf(stderr,"Starting %s\n", ctxdbg_cur); \
- ctxdbg(ctx); \
- } while(0)
-#define CTXDBG_EXIT(ctx) do { \
- fprintf(stderr,"Ending %s\n", ctxdbg_cur); \
- ctxdbg(ctx); \
- } while(0)
-#define CTXDBG_RET(ctx,ret)
+{
+ unsigned int bnidx = 0, fpidx = 0;
+ BN_POOL_ITEM *item = ctx->pool.head;
+ BN_STACK *stack = &ctx->stack;
+ fprintf(stderr, "(%16p): ", ctx);
+ while (bnidx < ctx->used) {
+ fprintf(stderr, "%03x ", item->vals[bnidx++ % BN_CTX_POOL_SIZE].dmax);
+ if (!(bnidx % BN_CTX_POOL_SIZE))
+ item = item->next;
+ }
+ fprintf(stderr, "\n");
+ bnidx = 0;
+ fprintf(stderr, " : ");
+ while (fpidx < stack->depth) {
+ while (bnidx++ < stack->indexes[fpidx])
+ fprintf(stderr, " ");
+ fprintf(stderr, "^^^ ");
+ bnidx++;
+ fpidx++;
+ }
+ fprintf(stderr, "\n");
+}
+
+# define CTXDBG_ENTRY(str, ctx) do { \
+ ctxdbg_cur = (str); \
+ fprintf(stderr,"Starting %s\n", ctxdbg_cur); \
+ ctxdbg(ctx); \
+ } while(0)
+# define CTXDBG_EXIT(ctx) do { \
+ fprintf(stderr,"Ending %s\n", ctxdbg_cur); \
+ ctxdbg(ctx); \
+ } while(0)
+# define CTXDBG_RET(ctx,ret)
#else
-#define CTXDBG_ENTRY(str, ctx)
-#define CTXDBG_EXIT(ctx)
-#define CTXDBG_RET(ctx,ret)
+# define CTXDBG_ENTRY(str, ctx)
+# define CTXDBG_EXIT(ctx)
+# define CTXDBG_RET(ctx,ret)
#endif
-/* This function is an evil legacy and should not be used. This implementation
- * is WYSIWYG, though I've done my best. */
-#ifndef OPENSSL_NO_DEPRECATED
-void BN_CTX_init(BN_CTX *ctx)
- {
- /* Assume the caller obtained the context via BN_CTX_new() and so is
- * trying to reset it for use. Nothing else makes sense, least of all
- * binary compatibility from a time when they could declare a static
- * variable. */
- BN_POOL_reset(&ctx->pool);
- BN_STACK_reset(&ctx->stack);
- ctx->used = 0;
- ctx->err_stack = 0;
- ctx->too_many = 0;
- }
-#endif
BN_CTX *BN_CTX_new(void)
- {
- BN_CTX *ret = OPENSSL_malloc(sizeof(BN_CTX));
- if(!ret)
- {
- BNerr(BN_F_BN_CTX_NEW,ERR_R_MALLOC_FAILURE);
- return NULL;
- }
- /* Initialise the structure */
- BN_POOL_init(&ret->pool);
- BN_STACK_init(&ret->stack);
- ret->used = 0;
- ret->err_stack = 0;
- ret->too_many = 0;
- return ret;
- }
+{
+ BN_CTX *ret;
+
+ if ((ret = OPENSSL_zalloc(sizeof(*ret))) == NULL) {
+ BNerr(BN_F_BN_CTX_NEW, ERR_R_MALLOC_FAILURE);
+ return NULL;
+ }
+ /* Initialise the structure */
+ BN_POOL_init(&ret->pool);
+ BN_STACK_init(&ret->stack);
+ return ret;
+}
+
+BN_CTX *BN_CTX_secure_new(void)
+{
+ BN_CTX *ret = BN_CTX_new();
+
+ if (ret != NULL)
+ ret->flags = BN_FLG_SECURE;
+ return ret;
+}
void BN_CTX_free(BN_CTX *ctx)
- {
- if (ctx == NULL)
- return;
+{
#ifdef BN_CTX_DEBUG
- {
- BN_POOL_ITEM *pool = ctx->pool.head;
- fprintf(stderr,"BN_CTX_free, stack-size=%d, pool-bignums=%d\n",
- ctx->stack.size, ctx->pool.size);
- fprintf(stderr,"dmaxs: ");
- while(pool) {
- unsigned loop = 0;
- while(loop < BN_CTX_POOL_SIZE)
- fprintf(stderr,"%02x ", pool->vals[loop++].dmax);
- pool = pool->next;
- }
- fprintf(stderr,"\n");
- }
+ {
+ BN_POOL_ITEM *pool = ctx->pool.head;
+ fprintf(stderr, "BN_CTX_free, stack-size=%d, pool-bignums=%d\n",
+ ctx->stack.size, ctx->pool.size);
+ fprintf(stderr, "dmaxs: ");
+ while (pool) {
+ unsigned loop = 0;
+ while (loop < BN_CTX_POOL_SIZE)
+ fprintf(stderr, "%02x ", pool->vals[loop++].dmax);
+ pool = pool->next;
+ }
+ fprintf(stderr, "\n");
+ }
#endif
- BN_STACK_finish(&ctx->stack);
- BN_POOL_finish(&ctx->pool);
- OPENSSL_free(ctx);
- }
+ BN_STACK_finish(&ctx->stack);
+ BN_POOL_finish(&ctx->pool);
+ OPENSSL_free(ctx);
+}
void BN_CTX_start(BN_CTX *ctx)
- {
- CTXDBG_ENTRY("BN_CTX_start", ctx);
- /* If we're already overflowing ... */
- if(ctx->err_stack || ctx->too_many)
- ctx->err_stack++;
- /* (Try to) get a new frame pointer */
- else if(!BN_STACK_push(&ctx->stack, ctx->used))
- {
- BNerr(BN_F_BN_CTX_START,BN_R_TOO_MANY_TEMPORARY_VARIABLES);
- ctx->err_stack++;
- }
- CTXDBG_EXIT(ctx);
- }
+{
+ CTXDBG_ENTRY("BN_CTX_start", ctx);
+ /* If we're already overflowing ... */
+ if (ctx->err_stack || ctx->too_many)
+ ctx->err_stack++;
+ /* (Try to) get a new frame pointer */
+ else if (!BN_STACK_push(&ctx->stack, ctx->used)) {
+ BNerr(BN_F_BN_CTX_START, BN_R_TOO_MANY_TEMPORARY_VARIABLES);
+ ctx->err_stack++;
+ }
+ CTXDBG_EXIT(ctx);
+}
void BN_CTX_end(BN_CTX *ctx)
- {
- CTXDBG_ENTRY("BN_CTX_end", ctx);
- if(ctx->err_stack)
- ctx->err_stack--;
- else
- {
- unsigned int fp = BN_STACK_pop(&ctx->stack);
- /* Does this stack frame have anything to release? */
- if(fp < ctx->used)
- BN_POOL_release(&ctx->pool, ctx->used - fp);
- ctx->used = fp;
- /* Unjam "too_many" in case "get" had failed */
- ctx->too_many = 0;
- }
- CTXDBG_EXIT(ctx);
- }
+{
+ CTXDBG_ENTRY("BN_CTX_end", ctx);
+ if (ctx->err_stack)
+ ctx->err_stack--;
+ else {
+ unsigned int fp = BN_STACK_pop(&ctx->stack);
+ /* Does this stack frame have anything to release? */
+ if (fp < ctx->used)
+ BN_POOL_release(&ctx->pool, ctx->used - fp);
+ ctx->used = fp;
+ /* Unjam "too_many" in case "get" had failed */
+ ctx->too_many = 0;
+ }
+ CTXDBG_EXIT(ctx);
+}
BIGNUM *BN_CTX_get(BN_CTX *ctx)
- {
- BIGNUM *ret;
- CTXDBG_ENTRY("BN_CTX_get", ctx);
- if(ctx->err_stack || ctx->too_many) return NULL;
- if((ret = BN_POOL_get(&ctx->pool)) == NULL)
- {
- /* Setting too_many prevents repeated "get" attempts from
- * cluttering the error stack. */
- ctx->too_many = 1;
- BNerr(BN_F_BN_CTX_GET,BN_R_TOO_MANY_TEMPORARY_VARIABLES);
- return NULL;
- }
- /* OK, make sure the returned bignum is "zero" */
- BN_zero(ret);
- ctx->used++;
- CTXDBG_RET(ctx, ret);
- return ret;
- }
+{
+ BIGNUM *ret;
+
+ CTXDBG_ENTRY("BN_CTX_get", ctx);
+ if (ctx->err_stack || ctx->too_many)
+ return NULL;
+ if ((ret = BN_POOL_get(&ctx->pool, ctx->flags)) == NULL) {
+ /*
+ * Setting too_many prevents repeated "get" attempts from cluttering
+ * the error stack.
+ */
+ ctx->too_many = 1;
+ BNerr(BN_F_BN_CTX_GET, BN_R_TOO_MANY_TEMPORARY_VARIABLES);
+ return NULL;
+ }
+ /* OK, make sure the returned bignum is "zero" */
+ BN_zero(ret);
+ ctx->used++;
+ CTXDBG_RET(ctx, ret);
+ return ret;
+}
/************/
/* BN_STACK */
/************/
static void BN_STACK_init(BN_STACK *st)
- {
- st->indexes = NULL;
- st->depth = st->size = 0;
- }
+{
+ st->indexes = NULL;
+ st->depth = st->size = 0;
+}
static void BN_STACK_finish(BN_STACK *st)
- {
- if(st->size) OPENSSL_free(st->indexes);
- }
-
-#ifndef OPENSSL_NO_DEPRECATED
-static void BN_STACK_reset(BN_STACK *st)
- {
- st->depth = 0;
- }
-#endif
+{
+ OPENSSL_free(st->indexes);
+ st->indexes = NULL;
+}
+
static int BN_STACK_push(BN_STACK *st, unsigned int idx)
- {
- if(st->depth == st->size)
- /* Need to expand */
- {
- unsigned int newsize = (st->size ?
- (st->size * 3 / 2) : BN_CTX_START_FRAMES);
- unsigned int *newitems = OPENSSL_malloc(newsize *
- sizeof(unsigned int));
- if(!newitems) return 0;
- if(st->depth)
- memcpy(newitems, st->indexes, st->depth *
- sizeof(unsigned int));
- if(st->size) OPENSSL_free(st->indexes);
- st->indexes = newitems;
- st->size = newsize;
- }
- st->indexes[(st->depth)++] = idx;
- return 1;
- }
+{
+ if (st->depth == st->size) {
+ /* Need to expand */
+ unsigned int newsize =
+ st->size ? (st->size * 3 / 2) : BN_CTX_START_FRAMES;
+ unsigned int *newitems = OPENSSL_malloc(sizeof(*newitems) * newsize);
+ if (newitems == NULL)
+ return 0;
+ if (st->depth)
+ memcpy(newitems, st->indexes, sizeof(*newitems) * st->depth);
+ OPENSSL_free(st->indexes);
+ st->indexes = newitems;
+ st->size = newsize;
+ }
+ st->indexes[(st->depth)++] = idx;
+ return 1;
+}
static unsigned int BN_STACK_pop(BN_STACK *st)
- {
- return st->indexes[--(st->depth)];
- }
+{
+ return st->indexes[--(st->depth)];
+}
/***********/
/* BN_POOL */
/***********/
static void BN_POOL_init(BN_POOL *p)
- {
- p->head = p->current = p->tail = NULL;
- p->used = p->size = 0;
- }
+{
+ p->head = p->current = p->tail = NULL;
+ p->used = p->size = 0;
+}
static void BN_POOL_finish(BN_POOL *p)
- {
- while(p->head)
- {
- unsigned int loop = 0;
- BIGNUM *bn = p->head->vals;
- while(loop++ < BN_CTX_POOL_SIZE)
- {
- if(bn->d) BN_clear_free(bn);
- bn++;
- }
- p->current = p->head->next;
- OPENSSL_free(p->head);
- p->head = p->current;
- }
- }
-
-#ifndef OPENSSL_NO_DEPRECATED
-static void BN_POOL_reset(BN_POOL *p)
- {
- BN_POOL_ITEM *item = p->head;
- while(item)
- {
- unsigned int loop = 0;
- BIGNUM *bn = item->vals;
- while(loop++ < BN_CTX_POOL_SIZE)
- {
- if(bn->d) BN_clear(bn);
- bn++;
- }
- item = item->next;
- }
- p->current = p->head;
- p->used = 0;
- }
-#endif
+{
+ unsigned int loop;
+ BIGNUM *bn;
+
+ while (p->head) {
+ for (loop = 0, bn = p->head->vals; loop++ < BN_CTX_POOL_SIZE; bn++)
+ if (bn->d)
+ BN_clear_free(bn);
+ p->current = p->head->next;
+ OPENSSL_free(p->head);
+ p->head = p->current;
+ }
+}
+
+
+static BIGNUM *BN_POOL_get(BN_POOL *p, int flag)
+{
+ BIGNUM *bn;
+ unsigned int loop;
+
+ /* Full; allocate a new pool item and link it in. */
+ if (p->used == p->size) {
+ BN_POOL_ITEM *item = OPENSSL_malloc(sizeof(*item));
+ if (item == NULL)
+ return NULL;
+ for (loop = 0, bn = item->vals; loop++ < BN_CTX_POOL_SIZE; bn++) {
+ bn_init(bn);
+ if ((flag & BN_FLG_SECURE) != 0)
+ BN_set_flags(bn, BN_FLG_SECURE);
+ }
+ item->prev = p->tail;
+ item->next = NULL;
+
+ if (p->head == NULL)
+ p->head = p->current = p->tail = item;
+ else {
+ p->tail->next = item;
+ p->tail = item;
+ p->current = item;
+ }
+ p->size += BN_CTX_POOL_SIZE;
+ p->used++;
+ /* Return the first bignum from the new pool */
+ return item->vals;
+ }
-static BIGNUM *BN_POOL_get(BN_POOL *p)
- {
- if(p->used == p->size)
- {
- BIGNUM *bn;
- unsigned int loop = 0;
- BN_POOL_ITEM *item = OPENSSL_malloc(sizeof(BN_POOL_ITEM));
- if(!item) return NULL;
- /* Initialise the structure */
- bn = item->vals;
- while(loop++ < BN_CTX_POOL_SIZE)
- BN_init(bn++);
- item->prev = p->tail;
- item->next = NULL;
- /* Link it in */
- if(!p->head)
- p->head = p->current = p->tail = item;
- else
- {
- p->tail->next = item;
- p->tail = item;
- p->current = item;
- }
- p->size += BN_CTX_POOL_SIZE;
- p->used++;
- /* Return the first bignum from the new pool */
- return item->vals;
- }
- if(!p->used)
- p->current = p->head;
- else if((p->used % BN_CTX_POOL_SIZE) == 0)
- p->current = p->current->next;
- return p->current->vals + ((p->used++) % BN_CTX_POOL_SIZE);
- }
+ if (!p->used)
+ p->current = p->head;
+ else if ((p->used % BN_CTX_POOL_SIZE) == 0)
+ p->current = p->current->next;
+ return p->current->vals + ((p->used++) % BN_CTX_POOL_SIZE);
+}
static void BN_POOL_release(BN_POOL *p, unsigned int num)
- {
- unsigned int offset = (p->used - 1) % BN_CTX_POOL_SIZE;
- p->used -= num;
- while(num--)
- {
- bn_check_top(p->current->vals + offset);
- if(!offset)
- {
- offset = BN_CTX_POOL_SIZE - 1;
- p->current = p->current->prev;
- }
- else
- offset--;
- }
- }
+{
+ unsigned int offset = (p->used - 1) % BN_CTX_POOL_SIZE;
+ p->used -= num;
+ while (num--) {
+ bn_check_top(p->current->vals + offset);
+ if (offset == 0) {
+ offset = BN_CTX_POOL_SIZE - 1;
+ p->current = p->current->prev;
+ } else
+ offset--;
+ }
+}
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