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/* crypto/bn/bn_ctx.c */ |
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/* Written by Ulf Moeller for the OpenSSL project. */ |
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/* ==================================================================== |
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* Copyright (c) 1998-2000 The OpenSSL Project. All rights reserved. |
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* |
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* Redistribution and use in source and binary forms, with or without |
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* modification, are permitted provided that the following conditions |
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* are met: |
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* |
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* 1. Redistributions of source code must retain the above copyright |
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* notice, this list of conditions and the following disclaimer. |
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* |
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* 2. Redistributions in binary form must reproduce the above copyright |
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* notice, this list of conditions and the following disclaimer in |
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* the documentation and/or other materials provided with the |
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* distribution. |
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* |
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* 3. All advertising materials mentioning features or use of this |
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* software must display the following acknowledgment: |
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* "This product includes software developed by the OpenSSL Project |
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* for use in the OpenSSL Toolkit. (http://www.openssl.org/)" |
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* |
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* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to |
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* endorse or promote products derived from this software without |
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* prior written permission. For written permission, please contact |
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* openssl-core@openssl.org. |
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* |
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* 5. Products derived from this software may not be called "OpenSSL" |
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* nor may "OpenSSL" appear in their names without prior written |
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* permission of the OpenSSL Project. |
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* |
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* 6. Redistributions of any form whatsoever must retain the following |
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* acknowledgment: |
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* "This product includes software developed by the OpenSSL Project |
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* for use in the OpenSSL Toolkit (http://www.openssl.org/)" |
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* |
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* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY |
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* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
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* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR |
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* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
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* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
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* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
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* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED |
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* OF THE POSSIBILITY OF SUCH DAMAGE. |
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* ==================================================================== |
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* |
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* This product includes cryptographic software written by Eric Young |
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* (eay@cryptsoft.com). This product includes software written by Tim |
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* Hudson (tjh@cryptsoft.com). |
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* |
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*/ |
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|
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#ifndef BN_CTX_DEBUG |
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# undef NDEBUG /* avoid conflicting definitions */ |
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# define NDEBUG |
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#endif |
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|
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#include <stdio.h> |
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#include <assert.h> |
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#include "bn.h" |
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|
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BN_CTX *BN_CTX_new(void) |
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{ |
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BN_CTX *ret; |
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|
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ret=(BN_CTX *)OPENSSL_malloc(sizeof(BN_CTX)); |
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if (ret == NULL) |
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{ |
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BNerr(BN_F_BN_CTX_NEW,ERR_R_MALLOC_FAILURE); |
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return(NULL); |
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} |
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|
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BN_CTX_init(ret); |
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ret->flags=BN_FLG_MALLOCED; |
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return(ret); |
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} |
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|
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void BN_CTX_init(BN_CTX *ctx) |
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{ |
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int i; |
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ctx->tos = 0; |
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ctx->flags = 0; |
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ctx->depth = 0; |
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ctx->too_many = 0; |
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for (i = 0; i < BN_CTX_NUM; i++) |
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BN_init(&(ctx->bn[i])); |
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} |
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|
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void BN_CTX_free(BN_CTX *ctx) |
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{ |
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int i; |
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|
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if (ctx == NULL) return; |
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assert(ctx->depth == 0); |
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|
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for (i=0; i < BN_CTX_NUM; i++) |
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BN_clear_free(&(ctx->bn[i])); |
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if (ctx->flags & BN_FLG_MALLOCED) |
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OPENSSL_free(ctx); |
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} |
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|
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void BN_CTX_start(BN_CTX *ctx) |
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{ |
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if (ctx->depth < BN_CTX_NUM_POS) |
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ctx->pos[ctx->depth] = ctx->tos; |
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ctx->depth++; |
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} |
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|
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BIGNUM *BN_CTX_get(BN_CTX *ctx) |
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{ |
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if (ctx->depth > BN_CTX_NUM_POS || ctx->tos >= BN_CTX_NUM) |
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{ |
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if (!ctx->too_many) |
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{ |
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BNerr(BN_F_BN_CTX_GET,BN_R_TOO_MANY_TEMPORARY_VARIABLES); |
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/* disable error code until BN_CTX_end is called: */ |
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ctx->too_many = 1; |
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} |
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return NULL; |
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} |
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return (&(ctx->bn[ctx->tos++])); |
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} |
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|
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void BN_CTX_end(BN_CTX *ctx) |
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{ |
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if (ctx == NULL) return; |
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assert(ctx->depth > 0); |
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if (ctx->depth == 0) |
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/* should never happen, but we can tolerate it if not in |
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* debug mode (could be a 'goto err' in the calling function |
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* before BN_CTX_start was reached) */ |
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BN_CTX_start(ctx); |
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|
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ctx->too_many = 0; |
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ctx->depth--; |
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if (ctx->depth < BN_CTX_NUM_POS) |
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ctx->tos = ctx->pos[ctx->depth]; |
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} |