diff options
Diffstat (limited to 'crypto/bn/bn_sqr.c')
-rw-r--r-- | crypto/bn/bn_sqr.c | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/crypto/bn/bn_sqr.c b/crypto/bn/bn_sqr.c new file mode 100644 index 0000000000..4c3f0a0986 --- /dev/null +++ b/crypto/bn/bn_sqr.c @@ -0,0 +1,161 @@ +/* crypto/bn/bn_sqr.c */ +/* Copyright (C) 1995-1997 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" + +/* r must not be a */ +/* I've just gone over this and it is now %20 faster on x86 - eay - 27 Jun 96 */ +int BN_sqr(r, a, ctx) +BIGNUM *r; +BIGNUM *a; +BN_CTX *ctx; + { + int i,j,max,al; + BIGNUM *tmp; + BN_ULONG *ap,*rp,c; + + tmp=ctx->bn[ctx->tos]; + + al=a->top; + if (al == 0) + { + r->top=0; + return(1); + } + + max=(al*2); + if (bn_expand(r,max*BN_BITS2) == NULL) return(0); + if (bn_expand(tmp,max*BN_BITS2) == NULL) return(0); + + r->neg=0; + + ap=a->d; + rp=r->d; + rp[0]=rp[max-1]=0; + rp++; + j=al; + + if (--j > 0) + { + ap++; + rp[j]=bn_mul_word(rp,ap,j,ap[-1]); + rp+=2; + } + + for (i=2; i<al; i++) + { + j--; + ap++; + rp[j]=bn_mul_add_word(rp,ap,j,ap[-1]); + rp+=2; + } + + /* inlined shift, 2 words at once */ + j=max; + rp=r->d; + c=0; + for (i=0; i<j; i++) + { + BN_ULONG t; + + t= *rp; + *(rp++)=((t<<1)|c)&BN_MASK2; + c=(t & BN_TBIT)?1:0; + +#if 0 + t= *rp; + *(rp++)=((t<<1)|c)&BN_MASK2; + c=(t & BN_TBIT)?1:0; +#endif + } + /* there will not be a carry */ + + bn_sqr_words(tmp->d,a->d,al); + + /* inlined add */ + ap=tmp->d; + rp=r->d; + c=0; + j=max; + for (i=0; i<j; i++) + { + BN_ULONG t1,t2; + + t1= *(ap++); + t2= *rp; + if (c) + { + c=(t2 >= ((~t1)&BN_MASK2)); + t2=(t1+t2+1)&BN_MASK2; + } + else + { + t2=(t1+t2)&BN_MASK2; + c=(t2<t1); + } + *(rp++)=t2; + } + /* there will be no carry */ + + r->top=max; + if (r->d[max-1] == 0) r->top--; + return(1); + } + |