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author | James <> | 2013-03-17 12:16:37 +0000 |
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committer | James <> | 2013-03-17 12:16:37 +0000 |
commit | 27b76ab0671089c47506615a796a261e993896a7 (patch) | |
tree | 61213d67e7fa87b20356b23798558e2c4212c42f /package/network/services/ead/src/tinysrp/bn_div.c | |
download | trunk-36060-master.tar.gz trunk-36060-master.tar.bz2 trunk-36060-master.zip |
Diffstat (limited to 'package/network/services/ead/src/tinysrp/bn_div.c')
-rw-r--r-- | package/network/services/ead/src/tinysrp/bn_div.c | 378 |
1 files changed, 378 insertions, 0 deletions
diff --git a/package/network/services/ead/src/tinysrp/bn_div.c b/package/network/services/ead/src/tinysrp/bn_div.c new file mode 100644 index 0000000..fd21913 --- /dev/null +++ b/package/network/services/ead/src/tinysrp/bn_div.c @@ -0,0 +1,378 @@ +/* crypto/bn/bn_div.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 "bn_lcl.h" + +#define NO_ASM + +/* The old slow way */ +#if 0 +int BN_div(BIGNUM *dv, BIGNUM *rem, const BIGNUM *m, const BIGNUM *d, + BN_CTX *ctx) + { + int i,nm,nd; + int ret = 0; + BIGNUM *D; + + bn_check_top(m); + bn_check_top(d); + if (BN_is_zero(d)) + { + return(0); + } + + if (BN_ucmp(m,d) < 0) + { + if (rem != NULL) + { if (BN_copy(rem,m) == NULL) return(0); } + if (dv != NULL) BN_zero(dv); + return(1); + } + + BN_CTX_start(ctx); + D = BN_CTX_get(ctx); + if (dv == NULL) dv = BN_CTX_get(ctx); + if (rem == NULL) rem = BN_CTX_get(ctx); + if (D == NULL || dv == NULL || rem == NULL) + goto end; + + nd=BN_num_bits(d); + nm=BN_num_bits(m); + if (BN_copy(D,d) == NULL) goto end; + if (BN_copy(rem,m) == NULL) goto end; + + /* The next 2 are needed so we can do a dv->d[0]|=1 later + * since BN_lshift1 will only work once there is a value :-) */ + BN_zero(dv); + bn_wexpand(dv,1); + dv->top=1; + + if (!BN_lshift(D,D,nm-nd)) goto end; + for (i=nm-nd; i>=0; i--) + { + if (!BN_lshift1(dv,dv)) goto end; + if (BN_ucmp(rem,D) >= 0) + { + dv->d[0]|=1; + if (!BN_usub(rem,rem,D)) goto end; + } +/* CAN IMPROVE (and have now :=) */ + if (!BN_rshift1(D,D)) goto end; + } + rem->neg=BN_is_zero(rem)?0:m->neg; + dv->neg=m->neg^d->neg; + ret = 1; + end: + BN_CTX_end(ctx); + return(ret); + } + +#else + +#if !defined(NO_ASM) && !defined(NO_INLINE_ASM) && !defined(PEDANTIC) && !defined(BN_DIV3W) +# if defined(__GNUC__) && __GNUC__>=2 +# if defined(__i386) + /* + * There were two reasons for implementing this template: + * - GNU C generates a call to a function (__udivdi3 to be exact) + * in reply to ((((BN_ULLONG)n0)<<BN_BITS2)|n1)/d0 (I fail to + * understand why...); + * - divl doesn't only calculate quotient, but also leaves + * remainder in %edx which we can definitely use here:-) + * + * <appro@fy.chalmers.se> + */ +# define bn_div_words(n0,n1,d0) \ + ({ asm volatile ( \ + "divl %4" \ + : "=a"(q), "=d"(rem) \ + : "a"(n1), "d"(n0), "g"(d0) \ + : "cc"); \ + q; \ + }) +# define REMAINDER_IS_ALREADY_CALCULATED +# endif /* __<cpu> */ +# endif /* __GNUC__ */ +#endif /* NO_ASM */ + +int BN_div(BIGNUM *dv, BIGNUM *rm, const BIGNUM *num, const BIGNUM *divisor, + BN_CTX *ctx) + { + int norm_shift,i,j,loop; + BIGNUM *tmp,wnum,*snum,*sdiv,*res; + BN_ULONG *resp,*wnump; + BN_ULONG d0,d1; + int num_n,div_n; + + bn_check_top(num); + bn_check_top(divisor); + + if (BN_is_zero(divisor)) + { + return(0); + } + + if (BN_ucmp(num,divisor) < 0) + { + if (rm != NULL) + { if (BN_copy(rm,num) == NULL) return(0); } + if (dv != NULL) BN_zero(dv); + return(1); + } + + BN_CTX_start(ctx); + tmp=BN_CTX_get(ctx); + tmp->neg=0; + snum=BN_CTX_get(ctx); + sdiv=BN_CTX_get(ctx); + if (dv == NULL) + res=BN_CTX_get(ctx); + else res=dv; + if (res == NULL) goto err; + + /* First we normalise the numbers */ + norm_shift=BN_BITS2-((BN_num_bits(divisor))%BN_BITS2); + BN_lshift(sdiv,divisor,norm_shift); + sdiv->neg=0; + norm_shift+=BN_BITS2; + BN_lshift(snum,num,norm_shift); + snum->neg=0; + div_n=sdiv->top; + num_n=snum->top; + loop=num_n-div_n; + + /* Lets setup a 'window' into snum + * This is the part that corresponds to the current + * 'area' being divided */ + BN_init(&wnum); + wnum.d= &(snum->d[loop]); + wnum.top= div_n; + wnum.dmax= snum->dmax+1; /* a bit of a lie */ + + /* Get the top 2 words of sdiv */ + /* i=sdiv->top; */ + d0=sdiv->d[div_n-1]; + d1=(div_n == 1)?0:sdiv->d[div_n-2]; + + /* pointer to the 'top' of snum */ + wnump= &(snum->d[num_n-1]); + + /* Setup to 'res' */ + res->neg= (num->neg^divisor->neg); + if (!bn_wexpand(res,(loop+1))) goto err; + res->top=loop; + resp= &(res->d[loop-1]); + + /* space for temp */ + if (!bn_wexpand(tmp,(div_n+1))) goto err; + + if (BN_ucmp(&wnum,sdiv) >= 0) + { + if (!BN_usub(&wnum,&wnum,sdiv)) goto err; + *resp=1; + res->d[res->top-1]=1; + } + else + res->top--; + resp--; + + for (i=0; i<loop-1; i++) + { + BN_ULONG q,l0; +#ifdef BN_DIV3W + q=bn_div_3_words(wnump,d1,d0); +#else + BN_ULONG n0,n1,rem=0; + + n0=wnump[0]; + n1=wnump[-1]; + if (n0 == d0) + q=BN_MASK2; + else /* n0 < d0 */ + { +#ifdef BN_LLONG + BN_ULLONG t2; + +#if defined(BN_LLONG) && defined(BN_DIV2W) && !defined(bn_div_words) + q=(BN_ULONG)(((((BN_ULLONG)n0)<<BN_BITS2)|n1)/d0); +#else + q=bn_div_words(n0,n1,d0); +#endif + +#ifndef REMAINDER_IS_ALREADY_CALCULATED + /* + * rem doesn't have to be BN_ULLONG. The least we + * know it's less that d0, isn't it? + */ + rem=(n1-q*d0)&BN_MASK2; +#endif + t2=(BN_ULLONG)d1*q; + + for (;;) + { + if (t2 <= ((((BN_ULLONG)rem)<<BN_BITS2)|wnump[-2])) + break; + q--; + rem += d0; + if (rem < d0) break; /* don't let rem overflow */ + t2 -= d1; + } +#else /* !BN_LLONG */ + BN_ULONG t2l,t2h,ql,qh; + + q=bn_div_words(n0,n1,d0); +#ifndef REMAINDER_IS_ALREADY_CALCULATED + rem=(n1-q*d0)&BN_MASK2; +#endif + +#ifdef BN_UMULT_HIGH + t2l = d1 * q; + t2h = BN_UMULT_HIGH(d1,q); +#else + t2l=LBITS(d1); t2h=HBITS(d1); + ql =LBITS(q); qh =HBITS(q); + mul64(t2l,t2h,ql,qh); /* t2=(BN_ULLONG)d1*q; */ +#endif + + for (;;) + { + if ((t2h < rem) || + ((t2h == rem) && (t2l <= wnump[-2]))) + break; + q--; + rem += d0; + if (rem < d0) break; /* don't let rem overflow */ + if (t2l < d1) t2h--; t2l -= d1; + } +#endif /* !BN_LLONG */ + } +#endif /* !BN_DIV3W */ + + l0=bn_mul_words(tmp->d,sdiv->d,div_n,q); + wnum.d--; wnum.top++; + tmp->d[div_n]=l0; + for (j=div_n+1; j>0; j--) + if (tmp->d[j-1]) break; + tmp->top=j; + + j=wnum.top; + BN_sub(&wnum,&wnum,tmp); + + snum->top=snum->top+wnum.top-j; + + if (wnum.neg) + { + q--; + j=wnum.top; + BN_add(&wnum,&wnum,sdiv); + snum->top+=wnum.top-j; + } + *(resp--)=q; + wnump--; + } + if (rm != NULL) + { + BN_rshift(rm,snum,norm_shift); + rm->neg=num->neg; + } + BN_CTX_end(ctx); + return(1); +err: + BN_CTX_end(ctx); + return(0); + } + +#endif + +/* rem != m */ +int BN_mod(BIGNUM *rem, const BIGNUM *m, const BIGNUM *d, BN_CTX *ctx) + { +#if 0 /* The old slow way */ + int i,nm,nd; + BIGNUM *dv; + + if (BN_ucmp(m,d) < 0) + return((BN_copy(rem,m) == NULL)?0:1); + + BN_CTX_start(ctx); + dv=BN_CTX_get(ctx); + + if (!BN_copy(rem,m)) goto err; + + nm=BN_num_bits(rem); + nd=BN_num_bits(d); + if (!BN_lshift(dv,d,nm-nd)) goto err; + for (i=nm-nd; i>=0; i--) + { + if (BN_cmp(rem,dv) >= 0) + { + if (!BN_sub(rem,rem,dv)) goto err; + } + if (!BN_rshift1(dv,dv)) goto err; + } + BN_CTX_end(ctx); + return(1); + err: + BN_CTX_end(ctx); + return(0); +#else + return(BN_div(NULL,rem,m,d,ctx)); +#endif + } + |