X-Git-Url: https://git.openssl.org/gitweb/?p=openssl.git;a=blobdiff_plain;f=crypto%2Fbn%2Fbn_exp2.c;h=2fc71b4e53f7dc446571f3df4de1f53e9b575803;hp=4b41dae07896ccf0f844b03839e0651e67b830ff;hb=dcf6e50f48e6bab92dcd2dacb27fc17c0de34199;hpb=73c2522c7ce821f2c837b58eec7780fb43aa7d4f diff --git a/crypto/bn/bn_exp2.c b/crypto/bn/bn_exp2.c index 4b41dae078..2fc71b4e53 100644 --- a/crypto/bn/bn_exp2.c +++ b/crypto/bn/bn_exp2.c @@ -1,313 +1,201 @@ -/* crypto/bn/bn_exp2.c */ -/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) - * All rights reserved. - * - * This package is an SSL implementation written - * by Eric Young (eay@cryptsoft.com). - * The implementation was written so as to conform with Netscapes SSL. - * - * This library is free for commercial and non-commercial use as long as - * the following conditions are aheared to. The following conditions - * apply to all code found in this distribution, be it the RC4, RSA, - * lhash, DES, etc., code; not just the SSL code. The SSL documentation - * included with this distribution is covered by the same copyright terms - * except that the holder is Tim Hudson (tjh@cryptsoft.com). - * - * Copyright remains Eric Young's, and as such any Copyright notices in - * the code are not to be removed. - * If this package is used in a product, Eric Young should be given attribution - * as the author of the parts of the library used. - * This can be in the form of a textual message at program startup or - * in documentation (online or textual) provided with the package. - * - * 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 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 acknowledgement: - * "This product includes cryptographic software written by - * Eric Young (eay@cryptsoft.com)" - * The word 'cryptographic' can be left out if the rouines from the library - * being used are not cryptographic related :-). - * 4. If you include any Windows specific code (or a derivative thereof) from - * the apps directory (application code) you must include an acknowledgement: - * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" - * - * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND - * ANY EXPRESS 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 AUTHOR OR 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. - * - * The licence and distribution terms for any publically available version or - * derivative of this code cannot be changed. i.e. this code cannot simply be - * copied and put under another distribution licence - * [including the GNU Public Licence.] - */ -/* ==================================================================== - * Copyright (c) 1998-2000 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 1995-2017 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 */ #include -#include "cryptlib.h" +#include "internal/cryptlib.h" #include "bn_lcl.h" -#define TABLE_SIZE 32 +#define TABLE_SIZE 32 int BN_mod_exp2_mont(BIGNUM *rr, const BIGNUM *a1, const BIGNUM *p1, - const BIGNUM *a2, const BIGNUM *p2, const BIGNUM *m, - BN_CTX *ctx, BN_MONT_CTX *in_mont) - { - int i,j,bits,b,bits1,bits2,ret=0,wpos1,wpos2,window1,window2,wvalue1,wvalue2; - int r_is_one=1,ts1=0,ts2=0; - BIGNUM *d,*r; - const BIGNUM *a_mod_m; - BIGNUM val1[TABLE_SIZE], val2[TABLE_SIZE]; - BN_MONT_CTX *mont=NULL; - - bn_check_top(a1); - bn_check_top(p1); - bn_check_top(a2); - bn_check_top(p2); - bn_check_top(m); - - if (!(m->d[0] & 1)) - { - BNerr(BN_F_BN_MOD_EXP2_MONT,BN_R_CALLED_WITH_EVEN_MODULUS); - return(0); - } - bits1=BN_num_bits(p1); - bits2=BN_num_bits(p2); - if ((bits1 == 0) && (bits2 == 0)) - { - ret = BN_one(rr); - return ret; - } - - bits=(bits1 > bits2)?bits1:bits2; - - BN_CTX_start(ctx); - d = BN_CTX_get(ctx); - r = BN_CTX_get(ctx); - if (d == NULL || r == NULL) goto err; - - if (in_mont != NULL) - mont=in_mont; - else - { - if ((mont=BN_MONT_CTX_new()) == NULL) goto err; - if (!BN_MONT_CTX_set(mont,m,ctx)) goto err; - } - - window1 = BN_window_bits_for_exponent_size(bits1); - window2 = BN_window_bits_for_exponent_size(bits2); - - /* - * Build table for a1: val1[i] := a1^(2*i + 1) mod m for i = 0 .. 2^(window1-1) - */ - BN_init(&val1[0]); - ts1=1; - if (a1->neg || BN_ucmp(a1,m) >= 0) - { - if (!BN_mod(&(val1[0]),a1,m,ctx)) - goto err; - a_mod_m = &(val1[0]); - } - else - a_mod_m = a1; - if (BN_is_zero(&(val1[0]))) - { - ret = BN_zero(rr); - goto err; - } - - if (!BN_to_montgomery(&(val1[0]),a_mod_m,mont,ctx)) goto err; - if (window1 > 1) - { - if (!BN_mod_mul_montgomery(d,&(val1[0]),&(val1[0]),mont,ctx)) goto err; - - j=1<<(window1-1); - for (i=1; ineg || BN_ucmp(a2,m) >= 0) - { - if (!BN_mod(&(val2[0]),a2,m,ctx)) - goto err; - a_mod_m = &(val2[0]); - } - else - a_mod_m = a2; - if (BN_is_zero(&(val2[0]))) - { - ret = BN_zero(rr); - goto err; - } - if (!BN_to_montgomery(&(val2[0]),a_mod_m,mont,ctx)) goto err; - if (window2 > 1) - { - if (!BN_mod_mul_montgomery(d,&(val2[0]),&(val2[0]),mont,ctx)) goto err; - - j=1<<(window2-1); - for (i=1; i 0, the bottom bit of the first window */ - wpos2=0; /* If wvalue2 > 0, the bottom bit of the second window */ - - if (!BN_to_montgomery(r,BN_value_one(),mont,ctx)) goto err; - for (b=bits-1; b>=0; b--) - { - if (!r_is_one) - { - if (!BN_mod_mul_montgomery(r,r,r,mont,ctx)) - goto err; - } - - if (!wvalue1) - if (BN_is_bit_set(p1, b)) - { - /* consider bits b-window1+1 .. b for this window */ - i = b-window1+1; - while (!BN_is_bit_set(p1, i)) /* works for i<0 */ - i++; - wpos1 = i; - wvalue1 = 1; - for (i = b-1; i >= wpos1; i--) - { - wvalue1 <<= 1; - if (BN_is_bit_set(p1, i)) - wvalue1++; - } - } - - if (!wvalue2) - if (BN_is_bit_set(p2, b)) - { - /* consider bits b-window2+1 .. b for this window */ - i = b-window2+1; - while (!BN_is_bit_set(p2, i)) - i++; - wpos2 = i; - wvalue2 = 1; - for (i = b-1; i >= wpos2; i--) - { - wvalue2 <<= 1; - if (BN_is_bit_set(p2, i)) - wvalue2++; - } - } - - if (wvalue1 && b == wpos1) - { - /* wvalue1 is odd and < 2^window1 */ - if (!BN_mod_mul_montgomery(r,r,&(val1[wvalue1>>1]),mont,ctx)) - goto err; - wvalue1 = 0; - r_is_one = 0; - } - - if (wvalue2 && b == wpos2) - { - /* wvalue2 is odd and < 2^window2 */ - if (!BN_mod_mul_montgomery(r,r,&(val2[wvalue2>>1]),mont,ctx)) - goto err; - wvalue2 = 0; - r_is_one = 0; - } - } - BN_from_montgomery(rr,r,mont,ctx); - ret=1; -err: - if ((in_mont == NULL) && (mont != NULL)) BN_MONT_CTX_free(mont); - BN_CTX_end(ctx); - for (i=0; id[0] & 1)) { + BNerr(BN_F_BN_MOD_EXP2_MONT, BN_R_CALLED_WITH_EVEN_MODULUS); + return (0); + } + bits1 = BN_num_bits(p1); + bits2 = BN_num_bits(p2); + if ((bits1 == 0) && (bits2 == 0)) { + ret = BN_one(rr); + return ret; + } + + bits = (bits1 > bits2) ? bits1 : bits2; + + BN_CTX_start(ctx); + d = BN_CTX_get(ctx); + r = BN_CTX_get(ctx); + val1[0] = BN_CTX_get(ctx); + val2[0] = BN_CTX_get(ctx); + if (val2[0] == NULL) + goto err; + + if (in_mont != NULL) + mont = in_mont; + else { + if ((mont = BN_MONT_CTX_new()) == NULL) + goto err; + if (!BN_MONT_CTX_set(mont, m, ctx)) + goto err; + } + + window1 = BN_window_bits_for_exponent_size(bits1); + window2 = BN_window_bits_for_exponent_size(bits2); + + /* + * Build table for a1: val1[i] := a1^(2*i + 1) mod m for i = 0 .. 2^(window1-1) + */ + if (a1->neg || BN_ucmp(a1, m) >= 0) { + if (!BN_mod(val1[0], a1, m, ctx)) + goto err; + a_mod_m = val1[0]; + } else + a_mod_m = a1; + if (BN_is_zero(a_mod_m)) { + BN_zero(rr); + ret = 1; + goto err; + } + + if (!BN_to_montgomery(val1[0], a_mod_m, mont, ctx)) + goto err; + if (window1 > 1) { + if (!BN_mod_mul_montgomery(d, val1[0], val1[0], mont, ctx)) + goto err; + + j = 1 << (window1 - 1); + for (i = 1; i < j; i++) { + if (((val1[i] = BN_CTX_get(ctx)) == NULL) || + !BN_mod_mul_montgomery(val1[i], val1[i - 1], d, mont, ctx)) + goto err; + } + } + + /* + * Build table for a2: val2[i] := a2^(2*i + 1) mod m for i = 0 .. 2^(window2-1) + */ + if (a2->neg || BN_ucmp(a2, m) >= 0) { + if (!BN_mod(val2[0], a2, m, ctx)) + goto err; + a_mod_m = val2[0]; + } else + a_mod_m = a2; + if (BN_is_zero(a_mod_m)) { + BN_zero(rr); + ret = 1; + goto err; + } + if (!BN_to_montgomery(val2[0], a_mod_m, mont, ctx)) + goto err; + if (window2 > 1) { + if (!BN_mod_mul_montgomery(d, val2[0], val2[0], mont, ctx)) + goto err; + + j = 1 << (window2 - 1); + for (i = 1; i < j; i++) { + if (((val2[i] = BN_CTX_get(ctx)) == NULL) || + !BN_mod_mul_montgomery(val2[i], val2[i - 1], d, mont, ctx)) + goto err; + } + } + + /* Now compute the power product, using independent windows. */ + r_is_one = 1; + wvalue1 = 0; /* The 'value' of the first window */ + wvalue2 = 0; /* The 'value' of the second window */ + wpos1 = 0; /* If wvalue1 > 0, the bottom bit of the + * first window */ + wpos2 = 0; /* If wvalue2 > 0, the bottom bit of the + * second window */ + + if (!BN_to_montgomery(r, BN_value_one(), mont, ctx)) + goto err; + for (b = bits - 1; b >= 0; b--) { + if (!r_is_one) { + if (!BN_mod_mul_montgomery(r, r, r, mont, ctx)) + goto err; + } + + if (!wvalue1) + if (BN_is_bit_set(p1, b)) { + /* + * consider bits b-window1+1 .. b for this window + */ + i = b - window1 + 1; + while (!BN_is_bit_set(p1, i)) /* works for i<0 */ + i++; + wpos1 = i; + wvalue1 = 1; + for (i = b - 1; i >= wpos1; i--) { + wvalue1 <<= 1; + if (BN_is_bit_set(p1, i)) + wvalue1++; + } + } + + if (!wvalue2) + if (BN_is_bit_set(p2, b)) { + /* + * consider bits b-window2+1 .. b for this window + */ + i = b - window2 + 1; + while (!BN_is_bit_set(p2, i)) + i++; + wpos2 = i; + wvalue2 = 1; + for (i = b - 1; i >= wpos2; i--) { + wvalue2 <<= 1; + if (BN_is_bit_set(p2, i)) + wvalue2++; + } + } + + if (wvalue1 && b == wpos1) { + /* wvalue1 is odd and < 2^window1 */ + if (!BN_mod_mul_montgomery(r, r, val1[wvalue1 >> 1], mont, ctx)) + goto err; + wvalue1 = 0; + r_is_one = 0; + } + + if (wvalue2 && b == wpos2) { + /* wvalue2 is odd and < 2^window2 */ + if (!BN_mod_mul_montgomery(r, r, val2[wvalue2 >> 1], mont, ctx)) + goto err; + wvalue2 = 0; + r_is_one = 0; + } + } + if (!BN_from_montgomery(rr, r, mont, ctx)) + goto err; + ret = 1; + err: + if (in_mont == NULL) + BN_MONT_CTX_free(mont); + BN_CTX_end(ctx); + bn_check_top(rr); + return (ret); +}