1656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project/* crypto/bn/bn_div.c */ 2656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 3656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * All rights reserved. 4656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * 5656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * This package is an SSL implementation written 6656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * by Eric Young (eay@cryptsoft.com). 7656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * The implementation was written so as to conform with Netscapes SSL. 8656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * 9656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * This library is free for commercial and non-commercial use as long as 10656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * the following conditions are aheared to. The following conditions 11656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * apply to all code found in this distribution, be it the RC4, RSA, 12656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * lhash, DES, etc., code; not just the SSL code. The SSL documentation 13656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * included with this distribution is covered by the same copyright terms 14656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * except that the holder is Tim Hudson (tjh@cryptsoft.com). 15656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * 16656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * Copyright remains Eric Young's, and as such any Copyright notices in 17656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * the code are not to be removed. 18656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * If this package is used in a product, Eric Young should be given attribution 19656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * as the author of the parts of the library used. 20656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * This can be in the form of a textual message at program startup or 21656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * in documentation (online or textual) provided with the package. 22656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * 23656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * Redistribution and use in source and binary forms, with or without 24656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * modification, are permitted provided that the following conditions 25656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * are met: 26656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * 1. Redistributions of source code must retain the copyright 27656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * notice, this list of conditions and the following disclaimer. 28656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * 2. Redistributions in binary form must reproduce the above copyright 29656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * notice, this list of conditions and the following disclaimer in the 30656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * documentation and/or other materials provided with the distribution. 31656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * 3. All advertising materials mentioning features or use of this software 32656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * must display the following acknowledgement: 33656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * "This product includes cryptographic software written by 34656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * Eric Young (eay@cryptsoft.com)" 35656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * The word 'cryptographic' can be left out if the rouines from the library 36656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * being used are not cryptographic related :-). 37656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * 4. If you include any Windows specific code (or a derivative thereof) from 38656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * the apps directory (application code) you must include an acknowledgement: 39656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" 40656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * 41656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 42656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 43656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 44656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 45656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 46656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 47656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 49656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 50656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 51656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * SUCH DAMAGE. 52656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * 53656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * The licence and distribution terms for any publically available version or 54656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * derivative of this code cannot be changed. i.e. this code cannot simply be 55656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * copied and put under another distribution licence 56656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * [including the GNU Public Licence.] 57656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project */ 58656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 59656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#include <stdio.h> 60656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#include <openssl/bn.h> 61656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#include "cryptlib.h" 62656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#include "bn_lcl.h" 63656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 64656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 65656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project/* The old slow way */ 66656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#if 0 67656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Projectint BN_div(BIGNUM *dv, BIGNUM *rem, const BIGNUM *m, const BIGNUM *d, 68656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project BN_CTX *ctx) 69656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project { 70656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project int i,nm,nd; 71656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project int ret = 0; 72656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project BIGNUM *D; 73656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 74656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project bn_check_top(m); 75656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project bn_check_top(d); 76656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (BN_is_zero(d)) 77656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project { 78656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project BNerr(BN_F_BN_DIV,BN_R_DIV_BY_ZERO); 79656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project return(0); 80656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project } 81656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 82656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (BN_ucmp(m,d) < 0) 83656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project { 84656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (rem != NULL) 85656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project { if (BN_copy(rem,m) == NULL) return(0); } 86656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (dv != NULL) BN_zero(dv); 87656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project return(1); 88656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project } 89656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 90656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project BN_CTX_start(ctx); 91656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project D = BN_CTX_get(ctx); 92656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (dv == NULL) dv = BN_CTX_get(ctx); 93656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (rem == NULL) rem = BN_CTX_get(ctx); 94656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (D == NULL || dv == NULL || rem == NULL) 95656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project goto end; 96656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 97656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project nd=BN_num_bits(d); 98656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project nm=BN_num_bits(m); 99656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (BN_copy(D,d) == NULL) goto end; 100656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (BN_copy(rem,m) == NULL) goto end; 101656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 102656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project /* The next 2 are needed so we can do a dv->d[0]|=1 later 103656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * since BN_lshift1 will only work once there is a value :-) */ 104656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project BN_zero(dv); 10598d58bb80c64b02a33662f0ea80351d4a1535267Brian Carlstrom if(bn_wexpand(dv,1) == NULL) goto end; 106656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project dv->top=1; 107656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 108656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (!BN_lshift(D,D,nm-nd)) goto end; 109656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project for (i=nm-nd; i>=0; i--) 110656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project { 111656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (!BN_lshift1(dv,dv)) goto end; 112656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (BN_ucmp(rem,D) >= 0) 113656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project { 114656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project dv->d[0]|=1; 115656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (!BN_usub(rem,rem,D)) goto end; 116656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project } 117656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project/* CAN IMPROVE (and have now :=) */ 118656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (!BN_rshift1(D,D)) goto end; 119656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project } 120656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project rem->neg=BN_is_zero(rem)?0:m->neg; 121656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project dv->neg=m->neg^d->neg; 122656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project ret = 1; 123656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project end: 124656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project BN_CTX_end(ctx); 125656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project return(ret); 126656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project } 127656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 128656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#else 129656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 130656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#if !defined(OPENSSL_NO_ASM) && !defined(OPENSSL_NO_INLINE_ASM) \ 131656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project && !defined(PEDANTIC) && !defined(BN_DIV3W) 132656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project# if defined(__GNUC__) && __GNUC__>=2 133656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project# if defined(__i386) || defined (__i386__) 134656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project /* 135656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * There were two reasons for implementing this template: 136656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * - GNU C generates a call to a function (__udivdi3 to be exact) 137656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * in reply to ((((BN_ULLONG)n0)<<BN_BITS2)|n1)/d0 (I fail to 138656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * understand why...); 139656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * - divl doesn't only calculate quotient, but also leaves 140656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * remainder in %edx which we can definitely use here:-) 141656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * 142656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * <appro@fy.chalmers.se> 143656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project */ 144656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project# define bn_div_words(n0,n1,d0) \ 145656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project ({ asm volatile ( \ 146656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project "divl %4" \ 147656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project : "=a"(q), "=d"(rem) \ 148656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project : "a"(n1), "d"(n0), "g"(d0) \ 149656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project : "cc"); \ 150656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project q; \ 151656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project }) 152656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project# define REMAINDER_IS_ALREADY_CALCULATED 153656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project# elif defined(__x86_64) && defined(SIXTY_FOUR_BIT_LONG) 154656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project /* 155656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * Same story here, but it's 128-bit by 64-bit division. Wow! 156656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * <appro@fy.chalmers.se> 157656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project */ 158656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project# define bn_div_words(n0,n1,d0) \ 159656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project ({ asm volatile ( \ 160656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project "divq %4" \ 161656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project : "=a"(q), "=d"(rem) \ 162656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project : "a"(n1), "d"(n0), "g"(d0) \ 163656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project : "cc"); \ 164656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project q; \ 165656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project }) 166656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project# define REMAINDER_IS_ALREADY_CALCULATED 167656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project# endif /* __<cpu> */ 168656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project# endif /* __GNUC__ */ 169656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#endif /* OPENSSL_NO_ASM */ 170656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 171656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 172392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom/* BN_div computes dv := num / divisor, rounding towards 173656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * zero, and sets up rm such that dv*divisor + rm = num holds. 174656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * Thus: 175656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * dv->neg == num->neg ^ divisor->neg (unless the result is zero) 176656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * rm->neg == num->neg (unless the remainder is zero) 177656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * If 'dv' or 'rm' is NULL, the respective value is not returned. 178656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project */ 179656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Projectint BN_div(BIGNUM *dv, BIGNUM *rm, const BIGNUM *num, const BIGNUM *divisor, 180656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project BN_CTX *ctx) 181656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project { 182656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project int norm_shift,i,loop; 183656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project BIGNUM *tmp,wnum,*snum,*sdiv,*res; 184656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project BN_ULONG *resp,*wnump; 185656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project BN_ULONG d0,d1; 186656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project int num_n,div_n; 187392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom int no_branch=0; 188656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 189e45f106cb6b47af1f21efe76e933bdea2f5dd1caNagendra Modadugu /* Invalid zero-padding would have particularly bad consequences 190e45f106cb6b47af1f21efe76e933bdea2f5dd1caNagendra Modadugu * in the case of 'num', so don't just rely on bn_check_top() for this one 191e45f106cb6b47af1f21efe76e933bdea2f5dd1caNagendra Modadugu * (bn_check_top() works only for BN_DEBUG builds) */ 192e45f106cb6b47af1f21efe76e933bdea2f5dd1caNagendra Modadugu if (num->top > 0 && num->d[num->top - 1] == 0) 193e45f106cb6b47af1f21efe76e933bdea2f5dd1caNagendra Modadugu { 194e45f106cb6b47af1f21efe76e933bdea2f5dd1caNagendra Modadugu BNerr(BN_F_BN_DIV,BN_R_NOT_INITIALIZED); 195e45f106cb6b47af1f21efe76e933bdea2f5dd1caNagendra Modadugu return 0; 196e45f106cb6b47af1f21efe76e933bdea2f5dd1caNagendra Modadugu } 197e45f106cb6b47af1f21efe76e933bdea2f5dd1caNagendra Modadugu 198e45f106cb6b47af1f21efe76e933bdea2f5dd1caNagendra Modadugu bn_check_top(num); 199e45f106cb6b47af1f21efe76e933bdea2f5dd1caNagendra Modadugu 200656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if ((BN_get_flags(num, BN_FLG_CONSTTIME) != 0) || (BN_get_flags(divisor, BN_FLG_CONSTTIME) != 0)) 201656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project { 202392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom no_branch=1; 203656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project } 204656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 205656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project bn_check_top(dv); 206656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project bn_check_top(rm); 207e45f106cb6b47af1f21efe76e933bdea2f5dd1caNagendra Modadugu /* bn_check_top(num); */ /* 'num' has been checked already */ 208656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project bn_check_top(divisor); 209656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 210656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (BN_is_zero(divisor)) 211656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project { 212656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project BNerr(BN_F_BN_DIV,BN_R_DIV_BY_ZERO); 213656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project return(0); 214656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project } 215656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 216392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom if (!no_branch && BN_ucmp(num,divisor) < 0) 217656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project { 218656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (rm != NULL) 219656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project { if (BN_copy(rm,num) == NULL) return(0); } 220656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (dv != NULL) BN_zero(dv); 221656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project return(1); 222656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project } 223656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 224656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project BN_CTX_start(ctx); 225656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project tmp=BN_CTX_get(ctx); 226656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project snum=BN_CTX_get(ctx); 227656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project sdiv=BN_CTX_get(ctx); 228656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (dv == NULL) 229656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project res=BN_CTX_get(ctx); 230656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project else res=dv; 23198d58bb80c64b02a33662f0ea80351d4a1535267Brian Carlstrom if (sdiv == NULL || res == NULL || tmp == NULL || snum == NULL) 23298d58bb80c64b02a33662f0ea80351d4a1535267Brian Carlstrom goto err; 233656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 234656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project /* First we normalise the numbers */ 235656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project norm_shift=BN_BITS2-((BN_num_bits(divisor))%BN_BITS2); 236656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (!(BN_lshift(sdiv,divisor,norm_shift))) goto err; 237656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project sdiv->neg=0; 238656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project norm_shift+=BN_BITS2; 239656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (!(BN_lshift(snum,num,norm_shift))) goto err; 240656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project snum->neg=0; 241656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 242392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom if (no_branch) 243656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project { 244392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom /* Since we don't know whether snum is larger than sdiv, 245392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom * we pad snum with enough zeroes without changing its 246392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom * value. 247392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom */ 248392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom if (snum->top <= sdiv->top+1) 249221304ee937bc0910948a8be1320cb8cc4eb6d36Brian Carlstrom { 250392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom if (bn_wexpand(snum, sdiv->top + 2) == NULL) goto err; 251392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom for (i = snum->top; i < sdiv->top + 2; i++) snum->d[i] = 0; 252392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom snum->top = sdiv->top + 2; 253221304ee937bc0910948a8be1320cb8cc4eb6d36Brian Carlstrom } 254392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom else 255656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project { 256392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom if (bn_wexpand(snum, snum->top + 1) == NULL) goto err; 257392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom snum->d[snum->top] = 0; 258392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom snum->top ++; 259656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project } 260656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project } 261656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 262656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project div_n=sdiv->top; 263656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project num_n=snum->top; 264656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project loop=num_n-div_n; 265656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project /* Lets setup a 'window' into snum 266656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * This is the part that corresponds to the current 267656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * 'area' being divided */ 268656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project wnum.neg = 0; 269656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project wnum.d = &(snum->d[loop]); 270656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project wnum.top = div_n; 271656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project /* only needed when BN_ucmp messes up the values between top and max */ 272656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project wnum.dmax = snum->dmax - loop; /* so we don't step out of bounds */ 273656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 274656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project /* Get the top 2 words of sdiv */ 275656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project /* div_n=sdiv->top; */ 276656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project d0=sdiv->d[div_n-1]; 277656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project d1=(div_n == 1)?0:sdiv->d[div_n-2]; 278656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 279656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project /* pointer to the 'top' of snum */ 280656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project wnump= &(snum->d[num_n-1]); 281656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 282656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project /* Setup to 'res' */ 283656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project res->neg= (num->neg^divisor->neg); 284656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (!bn_wexpand(res,(loop+1))) goto err; 285392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom res->top=loop-no_branch; 286656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project resp= &(res->d[loop-1]); 287656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 288656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project /* space for temp */ 289656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (!bn_wexpand(tmp,(div_n+1))) goto err; 290656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 291392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom if (!no_branch) 292392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom { 293392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom if (BN_ucmp(&wnum,sdiv) >= 0) 294392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom { 295392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom /* If BN_DEBUG_RAND is defined BN_ucmp changes (via 296392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom * bn_pollute) the const bignum arguments => 297392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom * clean the values between top and max again */ 298392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom bn_clear_top2max(&wnum); 299392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom bn_sub_words(wnum.d, wnum.d, sdiv->d, div_n); 300392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom *resp=1; 301392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom } 302392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom else 303392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom res->top--; 304392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom } 305392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom 306656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project /* if res->top == 0 then clear the neg value otherwise decrease 307656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * the resp pointer */ 308656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (res->top == 0) 309656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project res->neg = 0; 310656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project else 311656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project resp--; 312656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 313656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project for (i=0; i<loop-1; i++, wnump--, resp--) 314656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project { 315656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project BN_ULONG q,l0; 316656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project /* the first part of the loop uses the top two words of 317656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * snum and sdiv to calculate a BN_ULONG q such that 318656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * | wnum - sdiv * q | < sdiv */ 319656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#if defined(BN_DIV3W) && !defined(OPENSSL_NO_ASM) 320656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project BN_ULONG bn_div_3_words(BN_ULONG*,BN_ULONG,BN_ULONG); 321656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project q=bn_div_3_words(wnump,d1,d0); 322656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#else 323656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project BN_ULONG n0,n1,rem=0; 324656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 325656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project n0=wnump[0]; 326656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project n1=wnump[-1]; 327656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (n0 == d0) 328656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project q=BN_MASK2; 329656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project else /* n0 < d0 */ 330656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project { 331656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#ifdef BN_LLONG 332656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project BN_ULLONG t2; 333656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 334656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#if defined(BN_LLONG) && defined(BN_DIV2W) && !defined(bn_div_words) 335656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project q=(BN_ULONG)(((((BN_ULLONG)n0)<<BN_BITS2)|n1)/d0); 336656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#else 337656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project q=bn_div_words(n0,n1,d0); 338656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#ifdef BN_DEBUG_LEVITTE 339656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project fprintf(stderr,"DEBUG: bn_div_words(0x%08X,0x%08X,0x%08\ 340656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source ProjectX) -> 0x%08X\n", 341656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project n0, n1, d0, q); 342656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#endif 343656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#endif 344656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 345656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#ifndef REMAINDER_IS_ALREADY_CALCULATED 346656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project /* 347656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * rem doesn't have to be BN_ULLONG. The least we 348656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * know it's less that d0, isn't it? 349656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project */ 350656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project rem=(n1-q*d0)&BN_MASK2; 351656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#endif 352656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project t2=(BN_ULLONG)d1*q; 353656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 354656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project for (;;) 355656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project { 356656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (t2 <= ((((BN_ULLONG)rem)<<BN_BITS2)|wnump[-2])) 357656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project break; 358656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project q--; 359656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project rem += d0; 360656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (rem < d0) break; /* don't let rem overflow */ 361656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project t2 -= d1; 362656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project } 363656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#else /* !BN_LLONG */ 364221304ee937bc0910948a8be1320cb8cc4eb6d36Brian Carlstrom BN_ULONG t2l,t2h; 365656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 366656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project q=bn_div_words(n0,n1,d0); 367656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#ifdef BN_DEBUG_LEVITTE 368656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project fprintf(stderr,"DEBUG: bn_div_words(0x%08X,0x%08X,0x%08\ 369656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source ProjectX) -> 0x%08X\n", 370656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project n0, n1, d0, q); 371656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#endif 372656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#ifndef REMAINDER_IS_ALREADY_CALCULATED 373656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project rem=(n1-q*d0)&BN_MASK2; 374656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#endif 375656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 376656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#if defined(BN_UMULT_LOHI) 377656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project BN_UMULT_LOHI(t2l,t2h,d1,q); 378656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#elif defined(BN_UMULT_HIGH) 379656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project t2l = d1 * q; 380656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project t2h = BN_UMULT_HIGH(d1,q); 381656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#else 382221304ee937bc0910948a8be1320cb8cc4eb6d36Brian Carlstrom { 383221304ee937bc0910948a8be1320cb8cc4eb6d36Brian Carlstrom BN_ULONG ql, qh; 384656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project t2l=LBITS(d1); t2h=HBITS(d1); 385656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project ql =LBITS(q); qh =HBITS(q); 386656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project mul64(t2l,t2h,ql,qh); /* t2=(BN_ULLONG)d1*q; */ 387221304ee937bc0910948a8be1320cb8cc4eb6d36Brian Carlstrom } 388656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#endif 389656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 390656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project for (;;) 391656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project { 392656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if ((t2h < rem) || 393656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project ((t2h == rem) && (t2l <= wnump[-2]))) 394656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project break; 395656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project q--; 396656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project rem += d0; 397656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (rem < d0) break; /* don't let rem overflow */ 398656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (t2l < d1) t2h--; t2l -= d1; 399656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project } 400656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#endif /* !BN_LLONG */ 401656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project } 402656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#endif /* !BN_DIV3W */ 403656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project 404656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project l0=bn_mul_words(tmp->d,sdiv->d,div_n,q); 405656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project tmp->d[div_n]=l0; 406656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project wnum.d--; 407656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project /* ingore top values of the bignums just sub the two 408656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * BN_ULONG arrays with bn_sub_words */ 409656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (bn_sub_words(wnum.d, wnum.d, tmp->d, div_n+1)) 410656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project { 411656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project /* Note: As we have considered only the leading 412656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * two BN_ULONGs in the calculation of q, sdiv * q 413656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * might be greater than wnum (but then (q-1) * sdiv 414656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * is less or equal than wnum) 415656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project */ 416656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project q--; 417656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (bn_add_words(wnum.d, wnum.d, sdiv->d, div_n)) 418656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project /* we can't have an overflow here (assuming 419656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * that q != 0, but if q == 0 then tmp is 420656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * zero anyway) */ 421656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project (*wnump)++; 422656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project } 423656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project /* store part of the result */ 424656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project *resp = q; 425656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project } 426656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project bn_correct_top(snum); 427656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (rm != NULL) 428656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project { 429656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project /* Keep a copy of the neg flag in num because if rm==num 430656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project * BN_rshift() will overwrite it. 431656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project */ 432656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project int neg = num->neg; 433656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project BN_rshift(rm,snum,norm_shift); 434656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project if (!BN_is_zero(rm)) 435656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project rm->neg = neg; 436656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project bn_check_top(rm); 437656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project } 438392aa7cc7d2b122614c5393c3e357da07fd07af3Brian Carlstrom if (no_branch) bn_correct_top(res); 439656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project BN_CTX_end(ctx); 440656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project return(1); 441656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Projecterr: 442656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project bn_check_top(rm); 443656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project BN_CTX_end(ctx); 444656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project return(0); 445656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project } 446656d9c7f52f88b3a3daccafa7655dec086c4756eThe Android Open Source Project#endif 447