+++ /dev/null
-/*
- * Copyright (c) 2000-2001 Apple Computer, Inc. All Rights Reserved.
- *
- * The contents of this file constitute Original Code as defined in and are
- * subject to the Apple Public Source License Version 1.2 (the 'License').
- * You may not use this file except in compliance with the License. Please obtain
- * a copy of the License at http://www.apple.com/publicsource and read it before
- * using this file.
- *
- * This Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS
- * OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, INCLUDING WITHOUT
- * LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
- * PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. Please see the License for the
- * specific language governing rights and limitations under the License.
- */
-
-
-/* crypto/bn/bn_gcd.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.]
- */
-
-#include <stdio.h>
-#include "cryptlib.h"
-#include "bn_lcl.h"
-
-static BIGNUM *euclid(BIGNUM *a, BIGNUM *b);
-
-int BN_gcd(BIGNUM *r, BIGNUM *in_a, BIGNUM *in_b, BN_CTX *ctx)
- {
- BIGNUM *a,*b,*t;
- int ret=0;
-
- bn_check_top(in_a);
- bn_check_top(in_b);
-
- BN_CTX_start(ctx);
- a = BN_CTX_get(ctx);
- b = BN_CTX_get(ctx);
- if (a == NULL || b == NULL) goto err;
-
- if (BN_copy(a,in_a) == NULL) goto err;
- if (BN_copy(b,in_b) == NULL) goto err;
-
- if (BN_cmp(a,b) < 0) { t=a; a=b; b=t; }
- t=euclid(a,b);
- if (t == NULL) goto err;
-
- if (BN_copy(r,t) == NULL) goto err;
- ret=1;
-err:
- BN_CTX_end(ctx);
- return(ret);
- }
-
-static BIGNUM *euclid(BIGNUM *a, BIGNUM *b)
- {
- BIGNUM *t;
- int shifts=0;
-
- bn_check_top(a);
- bn_check_top(b);
-
- for (;;)
- {
- if (BN_is_zero(b))
- break;
-
- if (BN_is_odd(a))
- {
- if (BN_is_odd(b))
- {
- if (!BN_sub(a,a,b)) goto err;
- if (!BN_rshift1(a,a)) goto err;
- if (BN_cmp(a,b) < 0)
- { t=a; a=b; b=t; }
- }
- else /* a odd - b even */
- {
- if (!BN_rshift1(b,b)) goto err;
- if (BN_cmp(a,b) < 0)
- { t=a; a=b; b=t; }
- }
- }
- else /* a is even */
- {
- if (BN_is_odd(b))
- {
- if (!BN_rshift1(a,a)) goto err;
- if (BN_cmp(a,b) < 0)
- { t=a; a=b; b=t; }
- }
- else /* a even - b even */
- {
- if (!BN_rshift1(a,a)) goto err;
- if (!BN_rshift1(b,b)) goto err;
- shifts++;
- }
- }
- }
- if (shifts)
- {
- if (!BN_lshift(a,a,shifts)) goto err;
- }
- return(a);
-err:
- return(NULL);
- }
-
-/* solves ax == 1 (mod n) */
-BIGNUM *BN_mod_inverse(BIGNUM *in, BIGNUM *a, const BIGNUM *n, BN_CTX *ctx)
- {
- BIGNUM *A,*B,*X,*Y,*M,*D,*R=NULL;
- BIGNUM *T,*ret=NULL;
- int sign;
-
- bn_check_top(a);
- bn_check_top(n);
-
- BN_CTX_start(ctx);
- A = BN_CTX_get(ctx);
- B = BN_CTX_get(ctx);
- X = BN_CTX_get(ctx);
- D = BN_CTX_get(ctx);
- M = BN_CTX_get(ctx);
- Y = BN_CTX_get(ctx);
- if (Y == NULL) goto err;
-
- if (in == NULL)
- R=BN_new();
- else
- R=in;
- if (R == NULL) goto err;
-
- BN_zero(X);
- BN_one(Y);
- if (BN_copy(A,a) == NULL) goto err;
- if (BN_copy(B,n) == NULL) goto err;
- sign=1;
-
- while (!BN_is_zero(B))
- {
- if (!BN_div(D,M,A,B,ctx)) goto err;
- T=A;
- A=B;
- B=M;
- /* T has a struct, M does not */
-
- if (!BN_mul(T,D,X,ctx)) goto err;
- if (!BN_add(T,T,Y)) goto err;
- M=Y;
- Y=X;
- X=T;
- sign= -sign;
- }
- if (sign < 0)
- {
- if (!BN_sub(Y,n,Y)) goto err;
- }
-
- if (BN_is_one(A))
- { if (!BN_mod(R,Y,n,ctx)) goto err; }
- else
- {
- BNerr(BN_F_BN_MOD_INVERSE,BN_R_NO_INVERSE);
- goto err;
- }
- ret=R;
-err:
- if ((ret == NULL) && (in == NULL)) BN_free(R);
- BN_CTX_end(ctx);
- return(ret);
- }
-
projects / apple / security.git / blobdiff