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author | William Joye <wjoye@cfa.harvard.edu> | 2018-01-02 20:34:49 (GMT) |
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committer | William Joye <wjoye@cfa.harvard.edu> | 2018-01-02 20:34:49 (GMT) |
commit | 89c1ac99d375fbd73892aa659f06ef5e2c5ea56e (patch) | |
tree | e76ce80d68d11f1ea137bc33a42f71a1d1f32028 /tcl8.6/libtommath/bn_mp_dr_reduce.c | |
parent | 01e4cd2ef2ff59418766b2259fbc99771646aba6 (diff) | |
download | blt-89c1ac99d375fbd73892aa659f06ef5e2c5ea56e.zip blt-89c1ac99d375fbd73892aa659f06ef5e2c5ea56e.tar.gz blt-89c1ac99d375fbd73892aa659f06ef5e2c5ea56e.tar.bz2 |
upgrade to tcl/tk 8.6.8
Diffstat (limited to 'tcl8.6/libtommath/bn_mp_dr_reduce.c')
-rw-r--r-- | tcl8.6/libtommath/bn_mp_dr_reduce.c | 90 |
1 files changed, 0 insertions, 90 deletions
diff --git a/tcl8.6/libtommath/bn_mp_dr_reduce.c b/tcl8.6/libtommath/bn_mp_dr_reduce.c deleted file mode 100644 index 8337591..0000000 --- a/tcl8.6/libtommath/bn_mp_dr_reduce.c +++ /dev/null @@ -1,90 +0,0 @@ -#include <tommath.h> -#ifdef BN_MP_DR_REDUCE_C -/* LibTomMath, multiple-precision integer library -- Tom St Denis - * - * LibTomMath is a library that provides multiple-precision - * integer arithmetic as well as number theoretic functionality. - * - * The library was designed directly after the MPI library by - * Michael Fromberger but has been written from scratch with - * additional optimizations in place. - * - * The library is free for all purposes without any express - * guarantee it works. - * - * Tom St Denis, tomstdenis@gmail.com, http://math.libtomcrypt.com - */ - -/* reduce "x" in place modulo "n" using the Diminished Radix algorithm. - * - * Based on algorithm from the paper - * - * "Generating Efficient Primes for Discrete Log Cryptosystems" - * Chae Hoon Lim, Pil Joong Lee, - * POSTECH Information Research Laboratories - * - * The modulus must be of a special format [see manual] - * - * Has been modified to use algorithm 7.10 from the LTM book instead - * - * Input x must be in the range 0 <= x <= (n-1)**2 - */ -int -mp_dr_reduce (mp_int * x, mp_int * n, mp_digit k) -{ - int err, i, m; - mp_word r; - mp_digit mu, *tmpx1, *tmpx2; - - /* m = digits in modulus */ - m = n->used; - - /* ensure that "x" has at least 2m digits */ - if (x->alloc < m + m) { - if ((err = mp_grow (x, m + m)) != MP_OKAY) { - return err; - } - } - -/* top of loop, this is where the code resumes if - * another reduction pass is required. - */ -top: - /* aliases for digits */ - /* alias for lower half of x */ - tmpx1 = x->dp; - - /* alias for upper half of x, or x/B**m */ - tmpx2 = x->dp + m; - - /* set carry to zero */ - mu = 0; - - /* compute (x mod B**m) + k * [x/B**m] inline and inplace */ - for (i = 0; i < m; i++) { - r = ((mp_word)*tmpx2++) * ((mp_word)k) + *tmpx1 + mu; - *tmpx1++ = (mp_digit)(r & MP_MASK); - mu = (mp_digit)(r >> ((mp_word)DIGIT_BIT)); - } - - /* set final carry */ - *tmpx1++ = mu; - - /* zero words above m */ - for (i = m + 1; i < x->used; i++) { - *tmpx1++ = 0; - } - - /* clamp, sub and return */ - mp_clamp (x); - - /* if x >= n then subtract and reduce again - * Each successive "recursion" makes the input smaller and smaller. - */ - if (mp_cmp_mag (x, n) != MP_LT) { - s_mp_sub(x, n, x); - goto top; - } - return MP_OKAY; -} -#endif |