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-rw-r--r--tcl8.6/libtommath/bn_s_mp_exptmod.c248
1 files changed, 0 insertions, 248 deletions
diff --git a/tcl8.6/libtommath/bn_s_mp_exptmod.c b/tcl8.6/libtommath/bn_s_mp_exptmod.c
deleted file mode 100644
index ff6bd54..0000000
--- a/tcl8.6/libtommath/bn_s_mp_exptmod.c
+++ /dev/null
@@ -1,248 +0,0 @@
-#include <tommath.h>
-#ifdef BN_S_MP_EXPTMOD_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
- */
-#ifdef MP_LOW_MEM
- #define TAB_SIZE 32
-#else
- #define TAB_SIZE 256
-#endif
-
-int s_mp_exptmod (mp_int * G, mp_int * X, mp_int * P, mp_int * Y, int redmode)
-{
- mp_int M[TAB_SIZE], res, mu;
- mp_digit buf;
- int err, bitbuf, bitcpy, bitcnt, mode, digidx, x, y, winsize;
- int (*redux)(mp_int*,mp_int*,mp_int*);
-
- /* find window size */
- x = mp_count_bits (X);
- if (x <= 7) {
- winsize = 2;
- } else if (x <= 36) {
- winsize = 3;
- } else if (x <= 140) {
- winsize = 4;
- } else if (x <= 450) {
- winsize = 5;
- } else if (x <= 1303) {
- winsize = 6;
- } else if (x <= 3529) {
- winsize = 7;
- } else {
- winsize = 8;
- }
-
-#ifdef MP_LOW_MEM
- if (winsize > 5) {
- winsize = 5;
- }
-#endif
-
- /* init M array */
- /* init first cell */
- if ((err = mp_init(&M[1])) != MP_OKAY) {
- return err;
- }
-
- /* now init the second half of the array */
- for (x = 1<<(winsize-1); x < (1 << winsize); x++) {
- if ((err = mp_init(&M[x])) != MP_OKAY) {
- for (y = 1<<(winsize-1); y < x; y++) {
- mp_clear (&M[y]);
- }
- mp_clear(&M[1]);
- return err;
- }
- }
-
- /* create mu, used for Barrett reduction */
- if ((err = mp_init (&mu)) != MP_OKAY) {
- goto LBL_M;
- }
-
- if (redmode == 0) {
- if ((err = mp_reduce_setup (&mu, P)) != MP_OKAY) {
- goto LBL_MU;
- }
- redux = mp_reduce;
- } else {
- if ((err = mp_reduce_2k_setup_l (P, &mu)) != MP_OKAY) {
- goto LBL_MU;
- }
- redux = mp_reduce_2k_l;
- }
-
- /* create M table
- *
- * The M table contains powers of the base,
- * e.g. M[x] = G**x mod P
- *
- * The first half of the table is not
- * computed though accept for M[0] and M[1]
- */
- if ((err = mp_mod (G, P, &M[1])) != MP_OKAY) {
- goto LBL_MU;
- }
-
- /* compute the value at M[1<<(winsize-1)] by squaring
- * M[1] (winsize-1) times
- */
- if ((err = mp_copy (&M[1], &M[1 << (winsize - 1)])) != MP_OKAY) {
- goto LBL_MU;
- }
-
- for (x = 0; x < (winsize - 1); x++) {
- /* square it */
- if ((err = mp_sqr (&M[1 << (winsize - 1)],
- &M[1 << (winsize - 1)])) != MP_OKAY) {
- goto LBL_MU;
- }
-
- /* reduce modulo P */
- if ((err = redux (&M[1 << (winsize - 1)], P, &mu)) != MP_OKAY) {
- goto LBL_MU;
- }
- }
-
- /* create upper table, that is M[x] = M[x-1] * M[1] (mod P)
- * for x = (2**(winsize - 1) + 1) to (2**winsize - 1)
- */
- for (x = (1 << (winsize - 1)) + 1; x < (1 << winsize); x++) {
- if ((err = mp_mul (&M[x - 1], &M[1], &M[x])) != MP_OKAY) {
- goto LBL_MU;
- }
- if ((err = redux (&M[x], P, &mu)) != MP_OKAY) {
- goto LBL_MU;
- }
- }
-
- /* setup result */
- if ((err = mp_init (&res)) != MP_OKAY) {
- goto LBL_MU;
- }
- mp_set (&res, 1);
-
- /* set initial mode and bit cnt */
- mode = 0;
- bitcnt = 1;
- buf = 0;
- digidx = X->used - 1;
- bitcpy = 0;
- bitbuf = 0;
-
- for (;;) {
- /* grab next digit as required */
- if (--bitcnt == 0) {
- /* if digidx == -1 we are out of digits */
- if (digidx == -1) {
- break;
- }
- /* read next digit and reset the bitcnt */
- buf = X->dp[digidx--];
- bitcnt = (int) DIGIT_BIT;
- }
-
- /* grab the next msb from the exponent */
- y = (buf >> (mp_digit)(DIGIT_BIT - 1)) & 1;
- buf <<= (mp_digit)1;
-
- /* if the bit is zero and mode == 0 then we ignore it
- * These represent the leading zero bits before the first 1 bit
- * in the exponent. Technically this opt is not required but it
- * does lower the # of trivial squaring/reductions used
- */
- if (mode == 0 && y == 0) {
- continue;
- }
-
- /* if the bit is zero and mode == 1 then we square */
- if (mode == 1 && y == 0) {
- if ((err = mp_sqr (&res, &res)) != MP_OKAY) {
- goto LBL_RES;
- }
- if ((err = redux (&res, P, &mu)) != MP_OKAY) {
- goto LBL_RES;
- }
- continue;
- }
-
- /* else we add it to the window */
- bitbuf |= (y << (winsize - ++bitcpy));
- mode = 2;
-
- if (bitcpy == winsize) {
- /* ok window is filled so square as required and multiply */
- /* square first */
- for (x = 0; x < winsize; x++) {
- if ((err = mp_sqr (&res, &res)) != MP_OKAY) {
- goto LBL_RES;
- }
- if ((err = redux (&res, P, &mu)) != MP_OKAY) {
- goto LBL_RES;
- }
- }
-
- /* then multiply */
- if ((err = mp_mul (&res, &M[bitbuf], &res)) != MP_OKAY) {
- goto LBL_RES;
- }
- if ((err = redux (&res, P, &mu)) != MP_OKAY) {
- goto LBL_RES;
- }
-
- /* empty window and reset */
- bitcpy = 0;
- bitbuf = 0;
- mode = 1;
- }
- }
-
- /* if bits remain then square/multiply */
- if (mode == 2 && bitcpy > 0) {
- /* square then multiply if the bit is set */
- for (x = 0; x < bitcpy; x++) {
- if ((err = mp_sqr (&res, &res)) != MP_OKAY) {
- goto LBL_RES;
- }
- if ((err = redux (&res, P, &mu)) != MP_OKAY) {
- goto LBL_RES;
- }
-
- bitbuf <<= 1;
- if ((bitbuf & (1 << winsize)) != 0) {
- /* then multiply */
- if ((err = mp_mul (&res, &M[1], &res)) != MP_OKAY) {
- goto LBL_RES;
- }
- if ((err = redux (&res, P, &mu)) != MP_OKAY) {
- goto LBL_RES;
- }
- }
- }
- }
-
- mp_exch (&res, Y);
- err = MP_OKAY;
-LBL_RES:mp_clear (&res);
-LBL_MU:mp_clear (&mu);
-LBL_M:
- mp_clear(&M[1]);
- for (x = 1<<(winsize-1); x < (1 << winsize); x++) {
- mp_clear (&M[x]);
- }
- return err;
-}
-#endif
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