From 5ac03256db0fe4ca7e3ad1117d096c3a76368b76 Mon Sep 17 00:00:00 2001 From: Andreas Baumann Date: Fri, 9 Jan 2015 09:46:07 +0100 Subject: backported CyaSSL/OpenSSL support for internal webserver instead of MatrixSSL --- release/src/router/cyassl/ctaocrypt/src/tfm.c | 2430 +++++++++++++++++++++++++ 1 file changed, 2430 insertions(+) create mode 100644 release/src/router/cyassl/ctaocrypt/src/tfm.c (limited to 'release/src/router/cyassl/ctaocrypt/src/tfm.c') diff --git a/release/src/router/cyassl/ctaocrypt/src/tfm.c b/release/src/router/cyassl/ctaocrypt/src/tfm.c new file mode 100644 index 00000000..d14bcb6c --- /dev/null +++ b/release/src/router/cyassl/ctaocrypt/src/tfm.c @@ -0,0 +1,2430 @@ +/* tfm.c + * + * Copyright (C) 2006-2011 Sawtooth Consulting Ltd. + * + * This file is part of CyaSSL. + * + * CyaSSL is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * CyaSSL is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA + */ + +/* + * Based on public domain TomsFastMath 0.10 by Tom St Denis, tomstdenis@iahu.ca, + * http://math.libtomcrypt.com + */ + +/** + * Edited by Moisés Guimarães (moises.guimaraes@phoebus.com.br) + * to fit CyaSSL's needs. + */ + +#include "os_settings.h" /* in case user set USE_FAST_MATH there */ + +#ifdef USE_FAST_MATH + +#include "tfm.h" +#include "asm.c" /* will define asm MACROS or C ones */ + + + +/* Functions */ + +void fp_add(fp_int *a, fp_int *b, fp_int *c) +{ + int sa, sb; + + /* get sign of both inputs */ + sa = a->sign; + sb = b->sign; + + /* handle two cases, not four */ + if (sa == sb) { + /* both positive or both negative */ + /* add their magnitudes, copy the sign */ + c->sign = sa; + s_fp_add (a, b, c); + } else { + /* one positive, the other negative */ + /* subtract the one with the greater magnitude from */ + /* the one of the lesser magnitude. The result gets */ + /* the sign of the one with the greater magnitude. */ + if (fp_cmp_mag (a, b) == FP_LT) { + c->sign = sb; + s_fp_sub (b, a, c); + } else { + c->sign = sa; + s_fp_sub (a, b, c); + } + } +} + +/* unsigned addition */ +void s_fp_add(fp_int *a, fp_int *b, fp_int *c) +{ + int x, y, oldused; + register fp_word t; + + y = MAX(a->used, b->used); + oldused = c->used; + c->used = y; + + t = 0; + for (x = 0; x < y; x++) { + t += ((fp_word)a->dp[x]) + ((fp_word)b->dp[x]); + c->dp[x] = (fp_digit)t; + t >>= DIGIT_BIT; + } + if (t != 0 && x < FP_SIZE) { + c->dp[c->used++] = (fp_digit)t; + ++x; + } + + c->used = x; + for (; x < oldused; x++) { + c->dp[x] = 0; + } + fp_clamp(c); +} + +/* c = a - b */ +void fp_sub(fp_int *a, fp_int *b, fp_int *c) +{ + int sa, sb; + + sa = a->sign; + sb = b->sign; + + if (sa != sb) { + /* subtract a negative from a positive, OR */ + /* subtract a positive from a negative. */ + /* In either case, ADD their magnitudes, */ + /* and use the sign of the first number. */ + c->sign = sa; + s_fp_add (a, b, c); + } else { + /* subtract a positive from a positive, OR */ + /* subtract a negative from a negative. */ + /* First, take the difference between their */ + /* magnitudes, then... */ + if (fp_cmp_mag (a, b) != FP_LT) { + /* Copy the sign from the first */ + c->sign = sa; + /* The first has a larger or equal magnitude */ + s_fp_sub (a, b, c); + } else { + /* The result has the *opposite* sign from */ + /* the first number. */ + c->sign = (sa == FP_ZPOS) ? FP_NEG : FP_ZPOS; + /* The second has a larger magnitude */ + s_fp_sub (b, a, c); + } + } +} + +/* unsigned subtraction ||a|| >= ||b|| ALWAYS! */ +void s_fp_sub(fp_int *a, fp_int *b, fp_int *c) +{ + int x, oldbused, oldused; + fp_word t; + + oldused = c->used; + oldbused = b->used; + c->used = a->used; + t = 0; + for (x = 0; x < oldbused; x++) { + t = ((fp_word)a->dp[x]) - (((fp_word)b->dp[x]) + t); + c->dp[x] = (fp_digit)t; + t = (t >> DIGIT_BIT)&1; + } + for (; x < a->used; x++) { + t = ((fp_word)a->dp[x]) - t; + c->dp[x] = (fp_digit)t; + t = (t >> DIGIT_BIT); + } + for (; x < oldused; x++) { + c->dp[x] = 0; + } + fp_clamp(c); +} + +/* c = a * b */ +void fp_mul(fp_int *A, fp_int *B, fp_int *C) +{ + int y, yy; + + y = MAX(A->used, B->used); + yy = MIN(A->used, B->used); + + /* call generic if we're out of range */ + if (y + yy > FP_SIZE) { + fp_mul_comba(A, B, C); + return ; + } + + /* pick a comba (unrolled 4/8/16/32 x or rolled) based on the size + of the largest input. We also want to avoid doing excess mults if the + inputs are not close to the next power of two. That is, for example, + if say y=17 then we would do (32-17)^2 = 225 unneeded multiplications + */ + +#ifdef TFM_MUL3 + if (y <= 3) { + fp_mul_comba3(A,B,C); + return; + } +#endif +#ifdef TFM_MUL4 + if (y == 4) { + fp_mul_comba4(A,B,C); + return; + } +#endif +#ifdef TFM_MUL6 + if (y <= 6) { + fp_mul_comba6(A,B,C); + return; + } +#endif +#ifdef TFM_MUL7 + if (y == 7) { + fp_mul_comba7(A,B,C); + return; + } +#endif +#ifdef TFM_MUL8 + if (y == 8) { + fp_mul_comba8(A,B,C); + return; + } +#endif +#ifdef TFM_MUL9 + if (y == 9) { + fp_mul_comba9(A,B,C); + return; + } +#endif +#ifdef TFM_MUL12 + if (y <= 12) { + fp_mul_comba12(A,B,C); + return; + } +#endif +#ifdef TFM_MUL17 + if (y <= 17) { + fp_mul_comba17(A,B,C); + return; + } +#endif + +#ifdef TFM_SMALL_SET + if (y <= 16) { + fp_mul_comba_small(A,B,C); + return; + } +#endif +#if defined(TFM_MUL20) + if (y <= 20) { + fp_mul_comba20(A,B,C); + return; + } +#endif +#if defined(TFM_MUL24) + if (yy >= 16 && y <= 24) { + fp_mul_comba24(A,B,C); + return; + } +#endif +#if defined(TFM_MUL28) + if (yy >= 20 && y <= 28) { + fp_mul_comba28(A,B,C); + return; + } +#endif +#if defined(TFM_MUL32) + if (yy >= 24 && y <= 32) { + fp_mul_comba32(A,B,C); + return; + } +#endif +#if defined(TFM_MUL48) + if (yy >= 40 && y <= 48) { + fp_mul_comba48(A,B,C); + return; + } +#endif +#if defined(TFM_MUL64) + if (yy >= 56 && y <= 64) { + fp_mul_comba64(A,B,C); + return; + } +#endif + fp_mul_comba(A,B,C); +} + +void fp_mul_2(fp_int * a, fp_int * b) +{ + int x, oldused; + + oldused = b->used; + b->used = a->used; + + { + register fp_digit r, rr, *tmpa, *tmpb; + + /* alias for source */ + tmpa = a->dp; + + /* alias for dest */ + tmpb = b->dp; + + /* carry */ + r = 0; + for (x = 0; x < a->used; x++) { + + /* get what will be the *next* carry bit from the + * MSB of the current digit + */ + rr = *tmpa >> ((fp_digit)(DIGIT_BIT - 1)); + + /* now shift up this digit, add in the carry [from the previous] */ + *tmpb++ = ((*tmpa++ << ((fp_digit)1)) | r); + + /* copy the carry that would be from the source + * digit into the next iteration + */ + r = rr; + } + + /* new leading digit? */ + if (r != 0 && b->used != (FP_SIZE-1)) { + /* add a MSB which is always 1 at this point */ + *tmpb = 1; + ++(b->used); + } + + /* now zero any excess digits on the destination + * that we didn't write to + */ + tmpb = b->dp + b->used; + for (x = b->used; x < oldused; x++) { + *tmpb++ = 0; + } + } + b->sign = a->sign; +} + +/* c = a * b */ +void fp_mul_d(fp_int *a, fp_digit b, fp_int *c) +{ + fp_word w; + int x, oldused; + + oldused = c->used; + c->used = a->used; + c->sign = a->sign; + w = 0; + for (x = 0; x < a->used; x++) { + w = ((fp_word)a->dp[x]) * ((fp_word)b) + w; + c->dp[x] = (fp_digit)w; + w = w >> DIGIT_BIT; + } + if (w != 0 && (a->used != FP_SIZE)) { + c->dp[c->used++] = (fp_digit) w; + ++x; + } + for (; x < oldused; x++) { + c->dp[x] = 0; + } + fp_clamp(c); +} + +/* c = a * 2**d */ +void fp_mul_2d(fp_int *a, int b, fp_int *c) +{ + fp_digit carry, carrytmp, shift; + int x; + + /* copy it */ + fp_copy(a, c); + + /* handle whole digits */ + if (b >= DIGIT_BIT) { + fp_lshd(c, b/DIGIT_BIT); + } + b %= DIGIT_BIT; + + /* shift the digits */ + if (b != 0) { + carry = 0; + shift = DIGIT_BIT - b; + for (x = 0; x < c->used; x++) { + carrytmp = c->dp[x] >> shift; + c->dp[x] = (c->dp[x] << b) + carry; + carry = carrytmp; + } + /* store last carry if room */ + if (carry && x < FP_SIZE) { + c->dp[c->used++] = carry; + } + } + fp_clamp(c); +} + +/* generic PxQ multiplier */ +void fp_mul_comba(fp_int *A, fp_int *B, fp_int *C) +{ + int ix, iy, iz, tx, ty, pa; + fp_digit c0, c1, c2, *tmpx, *tmpy; + fp_int tmp, *dst; + + COMBA_START; + COMBA_CLEAR; + + /* get size of output and trim */ + pa = A->used + B->used; + if (pa >= FP_SIZE) { + pa = FP_SIZE-1; + } + + if (A == C || B == C) { + fp_zero(&tmp); + dst = &tmp; + } else { + fp_zero(C); + dst = C; + } + + for (ix = 0; ix < pa; ix++) { + /* get offsets into the two bignums */ + ty = MIN(ix, B->used-1); + tx = ix - ty; + + /* setup temp aliases */ + tmpx = A->dp + tx; + tmpy = B->dp + ty; + + /* this is the number of times the loop will iterrate, essentially its + while (tx++ < a->used && ty-- >= 0) { ... } + */ + iy = MIN(A->used-tx, ty+1); + + /* execute loop */ + COMBA_FORWARD; + for (iz = 0; iz < iy; ++iz) { + /* TAO change COMBA_ADD back to MULADD */ + MULADD(*tmpx++, *tmpy--); + } + + /* store term */ + COMBA_STORE(dst->dp[ix]); + } + COMBA_FINI; + + dst->used = pa; + dst->sign = A->sign ^ B->sign; + fp_clamp(dst); + fp_copy(dst, C); +} + +/* a/b => cb + d == a */ +int fp_div(fp_int *a, fp_int *b, fp_int *c, fp_int *d) +{ + fp_int q, x, y, t1, t2; + int n, t, i, norm, neg; + + /* is divisor zero ? */ + if (fp_iszero (b) == 1) { + return FP_VAL; + } + + /* if a < b then q=0, r = a */ + if (fp_cmp_mag (a, b) == FP_LT) { + if (d != NULL) { + fp_copy (a, d); + } + if (c != NULL) { + fp_zero (c); + } + return FP_OKAY; + } + + fp_init(&q); + q.used = a->used + 2; + + fp_init(&t1); + fp_init(&t2); + fp_init_copy(&x, a); + fp_init_copy(&y, b); + + /* fix the sign */ + neg = (a->sign == b->sign) ? FP_ZPOS : FP_NEG; + x.sign = y.sign = FP_ZPOS; + + /* normalize both x and y, ensure that y >= b/2, [b == 2**DIGIT_BIT] */ + norm = fp_count_bits(&y) % DIGIT_BIT; + if (norm < (int)(DIGIT_BIT-1)) { + norm = (DIGIT_BIT-1) - norm; + fp_mul_2d (&x, norm, &x); + fp_mul_2d (&y, norm, &y); + } else { + norm = 0; + } + + /* note hac does 0 based, so if used==5 then its 0,1,2,3,4, e.g. use 4 */ + n = x.used - 1; + t = y.used - 1; + + /* while (x >= y*b**n-t) do { q[n-t] += 1; x -= y*b**{n-t} } */ + fp_lshd (&y, n - t); /* y = y*b**{n-t} */ + + while (fp_cmp (&x, &y) != FP_LT) { + ++(q.dp[n - t]); + fp_sub (&x, &y, &x); + } + + /* reset y by shifting it back down */ + fp_rshd (&y, n - t); + + /* step 3. for i from n down to (t + 1) */ + for (i = n; i >= (t + 1); i--) { + if (i > x.used) { + continue; + } + + /* step 3.1 if xi == yt then set q{i-t-1} to b-1, + * otherwise set q{i-t-1} to (xi*b + x{i-1})/yt */ + if (x.dp[i] == y.dp[t]) { + q.dp[i - t - 1] = ((((fp_word)1) << DIGIT_BIT) - 1); + } else { + fp_word tmp; + tmp = ((fp_word) x.dp[i]) << ((fp_word) DIGIT_BIT); + tmp |= ((fp_word) x.dp[i - 1]); + tmp /= ((fp_word)y.dp[t]); + q.dp[i - t - 1] = (fp_digit) (tmp); + } + + /* while (q{i-t-1} * (yt * b + y{t-1})) > + xi * b**2 + xi-1 * b + xi-2 + + do q{i-t-1} -= 1; + */ + q.dp[i - t - 1] = (q.dp[i - t - 1] + 1); + do { + q.dp[i - t - 1] = (q.dp[i - t - 1] - 1); + + /* find left hand */ + fp_zero (&t1); + t1.dp[0] = (t - 1 < 0) ? 0 : y.dp[t - 1]; + t1.dp[1] = y.dp[t]; + t1.used = 2; + fp_mul_d (&t1, q.dp[i - t - 1], &t1); + + /* find right hand */ + t2.dp[0] = (i - 2 < 0) ? 0 : x.dp[i - 2]; + t2.dp[1] = (i - 1 < 0) ? 0 : x.dp[i - 1]; + t2.dp[2] = x.dp[i]; + t2.used = 3; + } while (fp_cmp_mag(&t1, &t2) == FP_GT); + + /* step 3.3 x = x - q{i-t-1} * y * b**{i-t-1} */ + fp_mul_d (&y, q.dp[i - t - 1], &t1); + fp_lshd (&t1, i - t - 1); + fp_sub (&x, &t1, &x); + + /* if x < 0 then { x = x + y*b**{i-t-1}; q{i-t-1} -= 1; } */ + if (x.sign == FP_NEG) { + fp_copy (&y, &t1); + fp_lshd (&t1, i - t - 1); + fp_add (&x, &t1, &x); + q.dp[i - t - 1] = q.dp[i - t - 1] - 1; + } + } + + /* now q is the quotient and x is the remainder + * [which we have to normalize] + */ + + /* get sign before writing to c */ + x.sign = x.used == 0 ? FP_ZPOS : a->sign; + + if (c != NULL) { + fp_clamp (&q); + fp_copy (&q, c); + c->sign = neg; + } + + if (d != NULL) { + fp_div_2d (&x, norm, &x, NULL); + +/* the following is a kludge, essentially we were seeing the right remainder but + with excess digits that should have been zero + */ + for (i = b->used; i < x.used; i++) { + x.dp[i] = 0; + } + fp_clamp(&x); + fp_copy (&x, d); + } + + return FP_OKAY; +} + +/* b = a/2 */ +void fp_div_2(fp_int * a, fp_int * b) +{ + int x, oldused; + + oldused = b->used; + b->used = a->used; + { + register fp_digit r, rr, *tmpa, *tmpb; + + /* source alias */ + tmpa = a->dp + b->used - 1; + + /* dest alias */ + tmpb = b->dp + b->used - 1; + + /* carry */ + r = 0; + for (x = b->used - 1; x >= 0; x--) { + /* get the carry for the next iteration */ + rr = *tmpa & 1; + + /* shift the current digit, add in carry and store */ + *tmpb-- = (*tmpa-- >> 1) | (r << (DIGIT_BIT - 1)); + + /* forward carry to next iteration */ + r = rr; + } + + /* zero excess digits */ + tmpb = b->dp + b->used; + for (x = b->used; x < oldused; x++) { + *tmpb++ = 0; + } + } + b->sign = a->sign; + fp_clamp (b); +} + +/* c = a / 2**b */ +void fp_div_2d(fp_int *a, int b, fp_int *c, fp_int *d) +{ + fp_digit D, r, rr; + int x; + fp_int t; + + /* if the shift count is <= 0 then we do no work */ + if (b <= 0) { + fp_copy (a, c); + if (d != NULL) { + fp_zero (d); + } + return; + } + + fp_init(&t); + + /* get the remainder */ + if (d != NULL) { + fp_mod_2d (a, b, &t); + } + + /* copy */ + fp_copy(a, c); + + /* shift by as many digits in the bit count */ + if (b >= (int)DIGIT_BIT) { + fp_rshd (c, b / DIGIT_BIT); + } + + /* shift any bit count < DIGIT_BIT */ + D = (fp_digit) (b % DIGIT_BIT); + if (D != 0) { + register fp_digit *tmpc, mask, shift; + + /* mask */ + mask = (((fp_digit)1) << D) - 1; + + /* shift for lsb */ + shift = DIGIT_BIT - D; + + /* alias */ + tmpc = c->dp + (c->used - 1); + + /* carry */ + r = 0; + for (x = c->used - 1; x >= 0; x--) { + /* get the lower bits of this word in a temp */ + rr = *tmpc & mask; + + /* shift the current word and mix in the carry bits from the previous word */ + *tmpc = (*tmpc >> D) | (r << shift); + --tmpc; + + /* set the carry to the carry bits of the current word found above */ + r = rr; + } + } + fp_clamp (c); + if (d != NULL) { + fp_copy (&t, d); + } +} + +/* c = a mod b, 0 <= c < b */ +int fp_mod(fp_int *a, fp_int *b, fp_int *c) +{ + fp_int t; + int err; + + fp_zero(&t); + if ((err = fp_div(a, b, NULL, &t)) != FP_OKAY) { + return err; + } + if (t.sign != b->sign) { + fp_add(&t, b, c); + } else { + fp_copy(&t, c); + } + return FP_OKAY; +} + +/* c = a mod 2**d */ +void fp_mod_2d(fp_int *a, int b, fp_int *c) +{ + int x; + + /* zero if count less than or equal to zero */ + if (b <= 0) { + fp_zero(c); + return; + } + + /* get copy of input */ + fp_copy(a, c); + + /* if 2**d is larger than we just return */ + if (b >= (DIGIT_BIT * a->used)) { + return; + } + + /* zero digits above the last digit of the modulus */ + for (x = (b / DIGIT_BIT) + ((b % DIGIT_BIT) == 0 ? 0 : 1); x < c->used; x++) { + c->dp[x] = 0; + } + /* clear the digit that is not completely outside/inside the modulus */ + c->dp[b / DIGIT_BIT] &= ~((fp_digit)0) >> (DIGIT_BIT - b); + fp_clamp (c); +} + +static int fp_invmod_slow (fp_int * a, fp_int * b, fp_int * c) +{ + fp_int x, y, u, v, A, B, C, D; + int res; + + /* b cannot be negative */ + if (b->sign == FP_NEG || fp_iszero(b) == 1) { + return FP_VAL; + } + + /* init temps */ + fp_init(&x); fp_init(&y); + fp_init(&u); fp_init(&v); + fp_init(&A); fp_init(&B); + fp_init(&C); fp_init(&D); + + /* x = a, y = b */ + if ((res = fp_mod(a, b, &x)) != FP_OKAY) { + return res; + } + fp_copy(b, &y); + + /* 2. [modified] if x,y are both even then return an error! */ + if (fp_iseven (&x) == 1 && fp_iseven (&y) == 1) { + return FP_VAL; + } + + /* 3. u=x, v=y, A=1, B=0, C=0,D=1 */ + fp_copy (&x, &u); + fp_copy (&y, &v); + fp_set (&A, 1); + fp_set (&D, 1); + +top: + /* 4. while u is even do */ + while (fp_iseven (&u) == 1) { + /* 4.1 u = u/2 */ + fp_div_2 (&u, &u); + + /* 4.2 if A or B is odd then */ + if (fp_isodd (&A) == 1 || fp_isodd (&B) == 1) { + /* A = (A+y)/2, B = (B-x)/2 */ + fp_add (&A, &y, &A); + fp_sub (&B, &x, &B); + } + /* A = A/2, B = B/2 */ + fp_div_2 (&A, &A); + fp_div_2 (&B, &B); + } + + /* 5. while v is even do */ + while (fp_iseven (&v) == 1) { + /* 5.1 v = v/2 */ + fp_div_2 (&v, &v); + + /* 5.2 if C or D is odd then */ + if (fp_isodd (&C) == 1 || fp_isodd (&D) == 1) { + /* C = (C+y)/2, D = (D-x)/2 */ + fp_add (&C, &y, &C); + fp_sub (&D, &x, &D); + } + /* C = C/2, D = D/2 */ + fp_div_2 (&C, &C); + fp_div_2 (&D, &D); + } + + /* 6. if u >= v then */ + if (fp_cmp (&u, &v) != FP_LT) { + /* u = u - v, A = A - C, B = B - D */ + fp_sub (&u, &v, &u); + fp_sub (&A, &C, &A); + fp_sub (&B, &D, &B); + } else { + /* v - v - u, C = C - A, D = D - B */ + fp_sub (&v, &u, &v); + fp_sub (&C, &A, &C); + fp_sub (&D, &B, &D); + } + + /* if not zero goto step 4 */ + if (fp_iszero (&u) == 0) + goto top; + + /* now a = C, b = D, gcd == g*v */ + + /* if v != 1 then there is no inverse */ + if (fp_cmp_d (&v, 1) != FP_EQ) { + return FP_VAL; + } + + /* if its too low */ + while (fp_cmp_d(&C, 0) == FP_LT) { + fp_add(&C, b, &C); + } + + /* too big */ + while (fp_cmp_mag(&C, b) != FP_LT) { + fp_sub(&C, b, &C); + } + + /* C is now the inverse */ + fp_copy(&C, c); + return FP_OKAY; +} + +/* c = 1/a (mod b) for odd b only */ +int fp_invmod(fp_int *a, fp_int *b, fp_int *c) +{ + fp_int x, y, u, v, B, D; + int neg; + + /* 2. [modified] b must be odd */ + if (fp_iseven (b) == FP_YES) { + return fp_invmod_slow(a,b,c); + } + + /* init all our temps */ + fp_init(&x); fp_init(&y); + fp_init(&u); fp_init(&v); + fp_init(&B); fp_init(&D); + + /* x == modulus, y == value to invert */ + fp_copy(b, &x); + + /* we need y = |a| */ + fp_abs(a, &y); + + /* 3. u=x, v=y, A=1, B=0, C=0,D=1 */ + fp_copy(&x, &u); + fp_copy(&y, &v); + fp_set (&D, 1); + +top: + /* 4. while u is even do */ + while (fp_iseven (&u) == FP_YES) { + /* 4.1 u = u/2 */ + fp_div_2 (&u, &u); + + /* 4.2 if B is odd then */ + if (fp_isodd (&B) == FP_YES) { + fp_sub (&B, &x, &B); + } + /* B = B/2 */ + fp_div_2 (&B, &B); + } + + /* 5. while v is even do */ + while (fp_iseven (&v) == FP_YES) { + /* 5.1 v = v/2 */ + fp_div_2 (&v, &v); + + /* 5.2 if D is odd then */ + if (fp_isodd (&D) == FP_YES) { + /* D = (D-x)/2 */ + fp_sub (&D, &x, &D); + } + /* D = D/2 */ + fp_div_2 (&D, &D); + } + + /* 6. if u >= v then */ + if (fp_cmp (&u, &v) != FP_LT) { + /* u = u - v, B = B - D */ + fp_sub (&u, &v, &u); + fp_sub (&B, &D, &B); + } else { + /* v - v - u, D = D - B */ + fp_sub (&v, &u, &v); + fp_sub (&D, &B, &D); + } + + /* if not zero goto step 4 */ + if (fp_iszero (&u) == FP_NO) { + goto top; + } + + /* now a = C, b = D, gcd == g*v */ + + /* if v != 1 then there is no inverse */ + if (fp_cmp_d (&v, 1) != FP_EQ) { + return FP_VAL; + } + + /* b is now the inverse */ + neg = a->sign; + while (D.sign == FP_NEG) { + fp_add (&D, b, &D); + } + fp_copy (&D, c); + c->sign = neg; + return FP_OKAY; +} + +/* d = a * b (mod c) */ +int fp_mulmod(fp_int *a, fp_int *b, fp_int *c, fp_int *d) +{ + fp_int tmp; + fp_zero(&tmp); + fp_mul(a, b, &tmp); + return fp_mod(&tmp, c, d); +} + +#ifdef TFM_TIMING_RESISTANT + +/* timing resistant montgomery ladder based exptmod + + Based on work by Marc Joye, Sung-Ming Yen, "The Montgomery Powering Ladder", Cryptographic Hardware and Embedded Systems, CHES 2002 +*/ +static int _fp_exptmod(fp_int * G, fp_int * X, fp_int * P, fp_int * Y) +{ + fp_int R[2]; + fp_digit buf, mp; + int err, bitcnt, digidx, y; + + /* now setup montgomery */ + if ((err = fp_montgomery_setup (P, &mp)) != FP_OKAY) { + return err; + } + + fp_init(&R[0]); + fp_init(&R[1]); + + /* now we need R mod m */ + fp_montgomery_calc_normalization (&R[0], P); + + /* now set R[0][1] to G * R mod m */ + if (fp_cmp_mag(P, G) != FP_GT) { + /* G > P so we reduce it first */ + fp_mod(G, P, &R[1]); + } else { + fp_copy(G, &R[1]); + } + fp_mulmod (&R[1], &R[0], P, &R[1]); + + /* for j = t-1 downto 0 do + r_!k = R0*R1; r_k = r_k^2 + */ + + /* set initial mode and bit cnt */ + bitcnt = 1; + buf = 0; + digidx = X->used - 1; + + for (;;) { + /* grab next digit as required */ + if (--bitcnt == 0) { + /* if digidx == -1 we are out of digits so break */ + if (digidx == -1) { + break; + } + /* read next digit and reset bitcnt */ + buf = X->dp[digidx--]; + bitcnt = (int)DIGIT_BIT; + } + + /* grab the next msb from the exponent */ + y = (fp_digit)(buf >> (DIGIT_BIT - 1)) & 1; + buf <<= (fp_digit)1; + + /* do ops */ + fp_mul(&R[0], &R[1], &R[y^1]); fp_montgomery_reduce(&R[y^1], P, mp); + fp_sqr(&R[y], &R[y]); fp_montgomery_reduce(&R[y], P, mp); + } + + fp_montgomery_reduce(&R[0], P, mp); + fp_copy(&R[0], Y); + return FP_OKAY; +} + +#else + +/* y = g**x (mod b) + * Some restrictions... x must be positive and < b + */ +static int _fp_exptmod(fp_int * G, fp_int * X, fp_int * P, fp_int * Y) +{ + fp_int M[64], res; + fp_digit buf, mp; + int err, bitbuf, bitcpy, bitcnt, mode, digidx, x, y, winsize; + + /* find window size */ + x = fp_count_bits (X); + if (x <= 21) { + winsize = 1; + } else if (x <= 36) { + winsize = 3; + } else if (x <= 140) { + winsize = 4; + } else if (x <= 450) { + winsize = 5; + } else { + winsize = 6; + } + + /* init M array */ + XMEMSET(M, 0, sizeof(M)); + + /* now setup montgomery */ + if ((err = fp_montgomery_setup (P, &mp)) != FP_OKAY) { + return err; + } + + /* setup result */ + fp_init(&res); + + /* create M table + * + * The M table contains powers of the input 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] + */ + + /* now we need R mod m */ + fp_montgomery_calc_normalization (&res, P); + + /* now set M[1] to G * R mod m */ + if (fp_cmp_mag(P, G) != FP_GT) { + /* G > P so we reduce it first */ + fp_mod(G, P, &M[1]); + } else { + fp_copy(G, &M[1]); + } + fp_mulmod (&M[1], &res, P, &M[1]); + + /* compute the value at M[1<<(winsize-1)] by squaring M[1] (winsize-1) times */ + fp_copy (&M[1], &M[1 << (winsize - 1)]); + for (x = 0; x < (winsize - 1); x++) { + fp_sqr (&M[1 << (winsize - 1)], &M[1 << (winsize - 1)]); + fp_montgomery_reduce (&M[1 << (winsize - 1)], P, mp); + } + + /* create upper table */ + for (x = (1 << (winsize - 1)) + 1; x < (1 << winsize); x++) { + fp_mul(&M[x - 1], &M[1], &M[x]); + fp_montgomery_reduce(&M[x], P, mp); + } + + /* 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 so break */ + if (digidx == -1) { + break; + } + /* read next digit and reset bitcnt */ + buf = X->dp[digidx--]; + bitcnt = (int)DIGIT_BIT; + } + + /* grab the next msb from the exponent */ + y = (fp_digit)(buf >> (DIGIT_BIT - 1)) & 1; + buf <<= (fp_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) { + fp_sqr(&res, &res); + fp_montgomery_reduce(&res, P, mp); + 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++) { + fp_sqr(&res, &res); + fp_montgomery_reduce(&res, P, mp); + } + + /* then multiply */ + fp_mul(&res, &M[bitbuf], &res); + fp_montgomery_reduce(&res, P, mp); + + /* 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++) { + fp_sqr(&res, &res); + fp_montgomery_reduce(&res, P, mp); + + /* get next bit of the window */ + bitbuf <<= 1; + if ((bitbuf & (1 << winsize)) != 0) { + /* then multiply */ + fp_mul(&res, &M[1], &res); + fp_montgomery_reduce(&res, P, mp); + } + } + } + + /* fixup result if Montgomery reduction is used + * recall that any value in a Montgomery system is + * actually multiplied by R mod n. So we have + * to reduce one more time to cancel out the factor + * of R. + */ + fp_montgomery_reduce(&res, P, mp); + + /* swap res with Y */ + fp_copy (&res, Y); + return FP_OKAY; +} + +#endif + +int fp_exptmod(fp_int * G, fp_int * X, fp_int * P, fp_int * Y) +{ + fp_int tmp; + int err; + + /* prevent overflows */ + if (P->used > (FP_SIZE/2)) { + return FP_VAL; + } + + /* is X negative? */ + if (X->sign == FP_NEG) { + /* yes, copy G and invmod it */ + fp_copy(G, &tmp); + if ((err = fp_invmod(&tmp, P, &tmp)) != FP_OKAY) { + return err; + } + X->sign = FP_ZPOS; + err = _fp_exptmod(&tmp, X, P, Y); + if (X != Y) { + X->sign = FP_NEG; + } + return err; + } else { + /* Positive exponent so just exptmod */ + return _fp_exptmod(G, X, P, Y); + } +} + +/* computes a = 2**b */ +void fp_2expt(fp_int *a, int b) +{ + int z; + + /* zero a as per default */ + fp_zero (a); + + if (b < 0) { + return; + } + + z = b / DIGIT_BIT; + if (z >= FP_SIZE) { + return; + } + + /* set the used count of where the bit will go */ + a->used = z + 1; + + /* put the single bit in its place */ + a->dp[z] = ((fp_digit)1) << (b % DIGIT_BIT); +} + +/* b = a*a */ +void fp_sqr(fp_int *A, fp_int *B) +{ + int y = A->used; + + /* call generic if we're out of range */ + if (y + y > FP_SIZE) { + fp_sqr_comba(A, B); + return ; + } + +#if defined(TFM_SQR3) + if (y <= 3) { + fp_sqr_comba3(A,B); + return; + } +#endif +#if defined(TFM_SQR4) + if (y == 4) { + fp_sqr_comba4(A,B); + return; + } +#endif +#if defined(TFM_SQR6) + if (y <= 6) { + fp_sqr_comba6(A,B); + return; + } +#endif +#if defined(TFM_SQR7) + if (y == 7) { + fp_sqr_comba7(A,B); + return; + } +#endif +#if defined(TFM_SQR8) + if (y == 8) { + fp_sqr_comba8(A,B); + return; + } +#endif +#if defined(TFM_SQR9) + if (y == 9) { + fp_sqr_comba9(A,B); + return; + } +#endif +#if defined(TFM_SQR12) + if (y <= 12) { + fp_sqr_comba12(A,B); + return; + } +#endif +#if defined(TFM_SQR17) + if (y <= 17) { + fp_sqr_comba17(A,B); + return; + } +#endif +#if defined(TFM_SMALL_SET) + if (y <= 16) { + fp_sqr_comba_small(A,B); + return; + } +#endif +#if defined(TFM_SQR20) + if (y <= 20) { + fp_sqr_comba20(A,B); + return; + } +#endif +#if defined(TFM_SQR24) + if (y <= 24) { + fp_sqr_comba24(A,B); + return; + } +#endif +#if defined(TFM_SQR28) + if (y <= 28) { + fp_sqr_comba28(A,B); + return; + } +#endif +#if defined(TFM_SQR32) + if (y <= 32) { + fp_sqr_comba32(A,B); + return; + } +#endif +#if defined(TFM_SQR48) + if (y <= 48) { + fp_sqr_comba48(A,B); + return; + } +#endif +#if defined(TFM_SQR64) + if (y <= 64) { + fp_sqr_comba64(A,B); + return; + } +#endif + fp_sqr_comba(A, B); +} + +/* generic comba squarer */ +void fp_sqr_comba(fp_int *A, fp_int *B) +{ + int pa, ix, iz; + fp_digit c0, c1, c2; + fp_int tmp, *dst; +#ifdef TFM_ISO + fp_word tt; +#endif + + /* get size of output and trim */ + pa = A->used + A->used; + if (pa >= FP_SIZE) { + pa = FP_SIZE-1; + } + + /* number of output digits to produce */ + COMBA_START; + COMBA_CLEAR; + + if (A == B) { + fp_zero(&tmp); + dst = &tmp; + } else { + fp_zero(B); + dst = B; + } + + for (ix = 0; ix < pa; ix++) { + int tx, ty, iy; + fp_digit *tmpy, *tmpx; + + /* get offsets into the two bignums */ + ty = MIN(A->used-1, ix); + tx = ix - ty; + + /* setup temp aliases */ + tmpx = A->dp + tx; + tmpy = A->dp + ty; + + /* this is the number of times the loop will iterrate, + while (tx++ < a->used && ty-- >= 0) { ... } + */ + iy = MIN(A->used-tx, ty+1); + + /* now for squaring tx can never equal ty + * we halve the distance since they approach + * at a rate of 2x and we have to round because + * odd cases need to be executed + */ + iy = MIN(iy, (ty-tx+1)>>1); + + /* forward carries */ + COMBA_FORWARD; + + /* execute loop */ + for (iz = 0; iz < iy; iz++) { + SQRADD2(*tmpx++, *tmpy--); + } + + /* even columns have the square term in them */ + if ((ix&1) == 0) { + /* TAO change COMBA_ADD back to SQRADD */ + SQRADD(A->dp[ix>>1], A->dp[ix>>1]); + } + + /* store it */ + COMBA_STORE(dst->dp[ix]); + } + + COMBA_FINI; + + /* setup dest */ + dst->used = pa; + fp_clamp (dst); + if (dst != B) { + fp_copy(dst, B); + } +} + +int fp_cmp(fp_int *a, fp_int *b) +{ + if (a->sign == FP_NEG && b->sign == FP_ZPOS) { + return FP_LT; + } else if (a->sign == FP_ZPOS && b->sign == FP_NEG) { + return FP_GT; + } else { + /* compare digits */ + if (a->sign == FP_NEG) { + /* if negative compare opposite direction */ + return fp_cmp_mag(b, a); + } else { + return fp_cmp_mag(a, b); + } + } +} + +/* compare against a single digit */ +int fp_cmp_d(fp_int *a, fp_digit b) +{ + /* compare based on sign */ + if ((b && a->used == 0) || a->sign == FP_NEG) { + return FP_LT; + } + + /* compare based on magnitude */ + if (a->used > 1) { + return FP_GT; + } + + /* compare the only digit of a to b */ + if (a->dp[0] > b) { + return FP_GT; + } else if (a->dp[0] < b) { + return FP_LT; + } else { + return FP_EQ; + } + +} + +int fp_cmp_mag(fp_int *a, fp_int *b) +{ + int x; + + if (a->used > b->used) { + return FP_GT; + } else if (a->used < b->used) { + return FP_LT; + } else { + for (x = a->used - 1; x >= 0; x--) { + if (a->dp[x] > b->dp[x]) { + return FP_GT; + } else if (a->dp[x] < b->dp[x]) { + return FP_LT; + } + } + } + return FP_EQ; +} + +/* setups the montgomery reduction */ +int fp_montgomery_setup(fp_int *a, fp_digit *rho) +{ + fp_digit x, b; + +/* fast inversion mod 2**k + * + * Based on the fact that + * + * XA = 1 (mod 2**n) => (X(2-XA)) A = 1 (mod 2**2n) + * => 2*X*A - X*X*A*A = 1 + * => 2*(1) - (1) = 1 + */ + b = a->dp[0]; + + if ((b & 1) == 0) { + return FP_VAL; + } + + x = (((b + 2) & 4) << 1) + b; /* here x*a==1 mod 2**4 */ + x *= 2 - b * x; /* here x*a==1 mod 2**8 */ + x *= 2 - b * x; /* here x*a==1 mod 2**16 */ + x *= 2 - b * x; /* here x*a==1 mod 2**32 */ +#ifdef FP_64BIT + x *= 2 - b * x; /* here x*a==1 mod 2**64 */ +#endif + + /* rho = -1/m mod b */ + *rho = (fp_digit) (((fp_word) 1 << ((fp_word) DIGIT_BIT)) - ((fp_word)x)); + + return FP_OKAY; +} + +/* computes a = B**n mod b without division or multiplication useful for + * normalizing numbers in a Montgomery system. + */ +void fp_montgomery_calc_normalization(fp_int *a, fp_int *b) +{ + int x, bits; + + /* how many bits of last digit does b use */ + bits = fp_count_bits (b) % DIGIT_BIT; + if (!bits) bits = DIGIT_BIT; + + /* compute A = B^(n-1) * 2^(bits-1) */ + if (b->used > 1) { + fp_2expt (a, (b->used - 1) * DIGIT_BIT + bits - 1); + } else { + fp_set(a, 1); + bits = 1; + } + + /* now compute C = A * B mod b */ + for (x = bits - 1; x < (int)DIGIT_BIT; x++) { + fp_mul_2 (a, a); + if (fp_cmp_mag (a, b) != FP_LT) { + s_fp_sub (a, b, a); + } + } +} + + +#ifdef TFM_SMALL_MONT_SET + #include "fp_mont_small.i" +#endif + +/* computes x/R == x (mod N) via Montgomery Reduction */ +void fp_montgomery_reduce(fp_int *a, fp_int *m, fp_digit mp) +{ + fp_digit c[FP_SIZE], *_c, *tmpm, mu; + int oldused, x, y, pa; + + /* bail if too large */ + if (m->used > (FP_SIZE/2)) { + (void)mu; /* shut up compiler */ + return; + } + +#ifdef TFM_SMALL_MONT_SET + if (m->used <= 16) { + fp_montgomery_reduce_small(a, m, mp); + return; + } +#endif + + +#if defined(USE_MEMSET) + /* now zero the buff */ + XMEMSET(c, 0, sizeof c); +#endif + pa = m->used; + + /* copy the input */ + oldused = a->used; + for (x = 0; x < oldused; x++) { + c[x] = a->dp[x]; + } +#if !defined(USE_MEMSET) + for (; x < 2*pa+1; x++) { + c[x] = 0; + } +#endif + MONT_START; + + for (x = 0; x < pa; x++) { + fp_digit cy = 0; + /* get Mu for this round */ + LOOP_START; + _c = c + x; + tmpm = m->dp; + y = 0; + #if (defined(TFM_SSE2) || defined(TFM_X86_64)) + for (; y < (pa & ~7); y += 8) { + INNERMUL8; + _c += 8; + tmpm += 8; + } + #endif + + for (; y < pa; y++) { + INNERMUL; + ++_c; + } + LOOP_END; + while (cy) { + PROPCARRY; + ++_c; + } + } + + /* now copy out */ + _c = c + pa; + tmpm = a->dp; + for (x = 0; x < pa+1; x++) { + *tmpm++ = *_c++; + } + + for (; x < oldused; x++) { + *tmpm++ = 0; + } + + MONT_FINI; + + a->used = pa+1; + fp_clamp(a); + + /* if A >= m then A = A - m */ + if (fp_cmp_mag (a, m) != FP_LT) { + s_fp_sub (a, m, a); + } +} + +void fp_read_unsigned_bin(fp_int *a, unsigned char *b, int c) +{ + /* zero the int */ + fp_zero (a); + + /* If we know the endianness of this architecture, and we're using + 32-bit fp_digits, we can optimize this */ +#if (defined(ENDIAN_LITTLE) || defined(ENDIAN_BIG)) && !defined(FP_64BIT) + /* But not for both simultaneously */ +#if defined(ENDIAN_LITTLE) && defined(ENDIAN_BIG) +#error Both ENDIAN_LITTLE and ENDIAN_BIG defined. +#endif + { + unsigned char *pd = (unsigned char *)a->dp; + + if ((unsigned)c > (FP_SIZE * sizeof(fp_digit))) { + int excess = c - (FP_SIZE * sizeof(fp_digit)); + c -= excess; + b += excess; + } + a->used = (c + sizeof(fp_digit) - 1)/sizeof(fp_digit); + /* read the bytes in */ +#ifdef ENDIAN_BIG + { + /* Use Duff's device to unroll the loop. */ + int idx = (c - 1) & ~3; + switch (c % 4) { + case 0: do { pd[idx+0] = *b++; + case 3: pd[idx+1] = *b++; + case 2: pd[idx+2] = *b++; + case 1: pd[idx+3] = *b++; + idx -= 4; + } while ((c -= 4) > 0); + } + } +#else + for (c -= 1; c >= 0; c -= 1) { + pd[c] = *b++; + } +#endif + } +#else + /* read the bytes in */ + for (; c > 0; c--) { + fp_mul_2d (a, 8, a); + a->dp[0] |= *b++; + a->used += 1; + } +#endif + fp_clamp (a); +} + +void fp_to_unsigned_bin(fp_int *a, unsigned char *b) +{ + int x; + fp_int t; + + fp_init_copy(&t, a); + + x = 0; + while (fp_iszero (&t) == FP_NO) { + b[x++] = (unsigned char) (t.dp[0] & 255); + fp_div_2d (&t, 8, &t, NULL); + } + fp_reverse (b, x); +} + +int fp_unsigned_bin_size(fp_int *a) +{ + int size = fp_count_bits (a); + return (size / 8 + ((size & 7) != 0 ? 1 : 0)); +} + +void fp_set(fp_int *a, fp_digit b) +{ + fp_zero(a); + a->dp[0] = b; + a->used = a->dp[0] ? 1 : 0; +} + +int fp_count_bits (fp_int * a) +{ + int r; + fp_digit q; + + /* shortcut */ + if (a->used == 0) { + return 0; + } + + /* get number of digits and add that */ + r = (a->used - 1) * DIGIT_BIT; + + /* take the last digit and count the bits in it */ + q = a->dp[a->used - 1]; + while (q > ((fp_digit) 0)) { + ++r; + q >>= ((fp_digit) 1); + } + return r; +} + +void fp_lshd(fp_int *a, int x) +{ + int y; + + /* move up and truncate as required */ + y = MIN(a->used + x - 1, (int)(FP_SIZE-1)); + + /* store new size */ + a->used = y + 1; + + /* move digits */ + for (; y >= x; y--) { + a->dp[y] = a->dp[y-x]; + } + + /* zero lower digits */ + for (; y >= 0; y--) { + a->dp[y] = 0; + } + + /* clamp digits */ + fp_clamp(a); +} + +void fp_rshd(fp_int *a, int x) +{ + int y; + + /* too many digits just zero and return */ + if (x >= a->used) { + fp_zero(a); + return; + } + + /* shift */ + for (y = 0; y < a->used - x; y++) { + a->dp[y] = a->dp[y+x]; + } + + /* zero rest */ + for (; y < a->used; y++) { + a->dp[y] = 0; + } + + /* decrement count */ + a->used -= x; + fp_clamp(a); +} + +/* reverse an array, used for radix code */ +void fp_reverse (unsigned char *s, int len) +{ + int ix, iy; + unsigned char t; + + ix = 0; + iy = len - 1; + while (ix < iy) { + t = s[ix]; + s[ix] = s[iy]; + s[iy] = t; + ++ix; + --iy; + } +} + + +/* CyaSSL callers from normal lib */ + +/* init a new mp_int */ +int mp_init (mp_int * a) +{ + if (a) + fp_init(a); + return MP_OKAY; +} + +/* clear one (frees) */ +void mp_clear (mp_int * a) +{ + fp_zero(a); +} + +/* handle up to 6 inits */ +int mp_init_multi(mp_int* a, mp_int* b, mp_int* c, mp_int* d, mp_int* e, mp_int* f) +{ + if (a) + fp_init(a); + if (b) + fp_init(b); + if (c) + fp_init(c); + if (d) + fp_init(d); + if (e) + fp_init(e); + if (f) + fp_init(f); + + return MP_OKAY; +} + +/* high level addition (handles signs) */ +int mp_add (mp_int * a, mp_int * b, mp_int * c) +{ + fp_add(a, b, c); + return MP_OKAY; +} + +/* high level subtraction (handles signs) */ +int mp_sub (mp_int * a, mp_int * b, mp_int * c) +{ + fp_sub(a, b, c); + return MP_OKAY; +} + +/* high level multiplication (handles sign) */ +int mp_mul (mp_int * a, mp_int * b, mp_int * c) +{ + fp_mul(a, b, c); + return MP_OKAY; +} + +/* d = a * b (mod c) */ +int mp_mulmod (mp_int * a, mp_int * b, mp_int * c, mp_int * d) +{ + return fp_mulmod(a, b, c, d); +} + +/* c = a mod b, 0 <= c < b */ +int mp_mod (mp_int * a, mp_int * b, mp_int * c) +{ + return fp_mod (a, b, c); +} + +/* hac 14.61, pp608 */ +int mp_invmod (mp_int * a, mp_int * b, mp_int * c) +{ + return fp_invmod(a, b, c); +} + +/* this is a shell function that calls either the normal or Montgomery + * exptmod functions. Originally the call to the montgomery code was + * embedded in the normal function but that wasted alot of stack space + * for nothing (since 99% of the time the Montgomery code would be called) + */ +int mp_exptmod (mp_int * G, mp_int * X, mp_int * P, mp_int * Y) +{ + return fp_exptmod(G, X, P, Y); +} + +/* compare two ints (signed)*/ +int mp_cmp (mp_int * a, mp_int * b) +{ + return fp_cmp(a, b); +} + +/* compare a digit */ +int mp_cmp_d(mp_int * a, mp_digit b) +{ + return fp_cmp_d(a, b); +} + +/* get the size for an unsigned equivalent */ +int mp_unsigned_bin_size (mp_int * a) +{ + return fp_unsigned_bin_size(a); +} + +/* store in unsigned [big endian] format */ +int mp_to_unsigned_bin (mp_int * a, unsigned char *b) +{ + fp_to_unsigned_bin(a,b); + return MP_OKAY; +} + +/* reads a unsigned char array, assumes the msb is stored first [big endian] */ +int mp_read_unsigned_bin (mp_int * a, const unsigned char *b, int c) +{ + fp_read_unsigned_bin(a, (unsigned char *)b, c); + return MP_OKAY; +} + + +#if defined(CYASSL_KEY_GEN) || defined (HAVE_ECC) + +/* c = a * a (mod b) */ +int fp_sqrmod(fp_int *a, fp_int *b, fp_int *c) +{ + fp_int tmp; + fp_zero(&tmp); + fp_sqr(a, &tmp); + return fp_mod(&tmp, b, c); +} + +/* fast math conversion */ +int mp_sqrmod(mp_int *a, mp_int *b, mp_int *c) +{ + return fp_sqrmod(a, b, c); +} + +/* fast math conversion */ +int mp_montgomery_calc_normalization(mp_int *a, mp_int *b) +{ + fp_montgomery_calc_normalization(a, b); + return MP_OKAY; +} + +/* fast math conversion */ +int mp_copy(fp_int* a, fp_int* b) +{ + fp_copy(a, b); + return MP_OKAY; +} + + +#endif /* CYASSL_KEYGEN || HAVE_ECC */ + + +#ifdef CYASSL_KEY_GEN + +void fp_gcd(fp_int *a, fp_int *b, fp_int *c); +void fp_lcm(fp_int *a, fp_int *b, fp_int *c); +void fp_sub_d(fp_int *a, fp_digit b, fp_int *c); +int fp_isprime(fp_int *a); +int fp_cnt_lsb(fp_int *a); + +/* fast math wrappers */ +int mp_set_int(fp_int *a, fp_digit b) +{ + fp_set(a, b); + return MP_OKAY; +} + + +int mp_gcd(fp_int *a, fp_int *b, fp_int *c) +{ + fp_gcd(a, b, c); + return MP_OKAY; +} + + +int mp_lcm(fp_int *a, fp_int *b, fp_int *c) +{ + fp_lcm(a, b, c); + return MP_OKAY; +} + + +int mp_sub_d(fp_int *a, fp_digit b, fp_int *c) +{ + fp_sub_d(a, b, c); + return MP_OKAY; +} + + +int mp_prime_is_prime(mp_int* a, int t, int* result) +{ + *result = fp_isprime(a); + return MP_OKAY; +} + + + +/* c = a - b */ +void fp_sub_d(fp_int *a, fp_digit b, fp_int *c) +{ + fp_int tmp; + fp_set(&tmp, b); + fp_sub(a, &tmp, c); +} + + +static int s_is_power_of_two(fp_digit b, int *p) +{ + int x; + + /* fast return if no power of two */ + if ((b==0) || (b & (b-1))) { + return 0; + } + + for (x = 0; x < DIGIT_BIT; x++) { + if (b == (((fp_digit)1)< cb + d == a */ +int fp_div_d(fp_int *a, fp_digit b, fp_int *c, fp_digit *d) +{ + fp_int q; + fp_word w; + fp_digit t; + int ix; + + /* cannot divide by zero */ + if (b == 0) { + return FP_VAL; + } + + /* quick outs */ + if (b == 1 || fp_iszero(a) == 1) { + if (d != NULL) { + *d = 0; + } + if (c != NULL) { + fp_copy(a, c); + } + return FP_OKAY; + } + + /* power of two ? */ + if (s_is_power_of_two(b, &ix) == 1) { + if (d != NULL) { + *d = a->dp[0] & ((((fp_digit)1)<used; + q.sign = a->sign; + w = 0; + for (ix = a->used - 1; ix >= 0; ix--) { + w = (w << ((fp_word)DIGIT_BIT)) | ((fp_word)a->dp[ix]); + + if (w >= b) { + t = (fp_digit)(w / b); + w -= ((fp_word)t) * ((fp_word)b); + } else { + t = 0; + } + q.dp[ix] = (fp_digit)t; + } + + if (d != NULL) { + *d = (fp_digit)w; + } + + if (c != NULL) { + fp_clamp(&q); + fp_copy(&q, c); + } + + return FP_OKAY; +} + + +/* c = a mod b, 0 <= c < b */ +int fp_mod_d(fp_int *a, fp_digit b, fp_digit *c) +{ + return fp_div_d(a, b, NULL, c); +} + + +/* Miller-Rabin test of "a" to the base of "b" as described in + * HAC pp. 139 Algorithm 4.24 + * + * Sets result to 0 if definitely composite or 1 if probably prime. + * Randomly the chance of error is no more than 1/4 and often + * very much lower. + */ +void fp_prime_miller_rabin (fp_int * a, fp_int * b, int *result) +{ + fp_int n1, y, r; + int s, j; + + /* default */ + *result = FP_NO; + + /* ensure b > 1 */ + if (fp_cmp_d(b, 1) != FP_GT) { + return; + } + + /* get n1 = a - 1 */ + fp_init_copy(&n1, a); + fp_sub_d(&n1, 1, &n1); + + /* set 2**s * r = n1 */ + fp_init_copy(&r, &n1); + + /* count the number of least significant bits + * which are zero + */ + s = fp_cnt_lsb(&r); + + /* now divide n - 1 by 2**s */ + fp_div_2d (&r, s, &r, NULL); + + /* compute y = b**r mod a */ + fp_init(&y); + fp_exptmod(b, &r, a, &y); + + /* if y != 1 and y != n1 do */ + if (fp_cmp_d (&y, 1) != FP_EQ && fp_cmp (&y, &n1) != FP_EQ) { + j = 1; + /* while j <= s-1 and y != n1 */ + while ((j <= (s - 1)) && fp_cmp (&y, &n1) != FP_EQ) { + fp_sqrmod (&y, a, &y); + + /* if y == 1 then composite */ + if (fp_cmp_d (&y, 1) == FP_EQ) { + return; + } + ++j; + } + + /* if y != n1 then composite */ + if (fp_cmp (&y, &n1) != FP_EQ) { + return; + } + } + + /* probably prime now */ + *result = FP_YES; +} + + +/* a few primes */ +static const fp_digit primes[256] = { + 0x0002, 0x0003, 0x0005, 0x0007, 0x000B, 0x000D, 0x0011, 0x0013, + 0x0017, 0x001D, 0x001F, 0x0025, 0x0029, 0x002B, 0x002F, 0x0035, + 0x003B, 0x003D, 0x0043, 0x0047, 0x0049, 0x004F, 0x0053, 0x0059, + 0x0061, 0x0065, 0x0067, 0x006B, 0x006D, 0x0071, 0x007F, 0x0083, + 0x0089, 0x008B, 0x0095, 0x0097, 0x009D, 0x00A3, 0x00A7, 0x00AD, + 0x00B3, 0x00B5, 0x00BF, 0x00C1, 0x00C5, 0x00C7, 0x00D3, 0x00DF, + 0x00E3, 0x00E5, 0x00E9, 0x00EF, 0x00F1, 0x00FB, 0x0101, 0x0107, + 0x010D, 0x010F, 0x0115, 0x0119, 0x011B, 0x0125, 0x0133, 0x0137, + + 0x0139, 0x013D, 0x014B, 0x0151, 0x015B, 0x015D, 0x0161, 0x0167, + 0x016F, 0x0175, 0x017B, 0x017F, 0x0185, 0x018D, 0x0191, 0x0199, + 0x01A3, 0x01A5, 0x01AF, 0x01B1, 0x01B7, 0x01BB, 0x01C1, 0x01C9, + 0x01CD, 0x01CF, 0x01D3, 0x01DF, 0x01E7, 0x01EB, 0x01F3, 0x01F7, + 0x01FD, 0x0209, 0x020B, 0x021D, 0x0223, 0x022D, 0x0233, 0x0239, + 0x023B, 0x0241, 0x024B, 0x0251, 0x0257, 0x0259, 0x025F, 0x0265, + 0x0269, 0x026B, 0x0277, 0x0281, 0x0283, 0x0287, 0x028D, 0x0293, + 0x0295, 0x02A1, 0x02A5, 0x02AB, 0x02B3, 0x02BD, 0x02C5, 0x02CF, + + 0x02D7, 0x02DD, 0x02E3, 0x02E7, 0x02EF, 0x02F5, 0x02F9, 0x0301, + 0x0305, 0x0313, 0x031D, 0x0329, 0x032B, 0x0335, 0x0337, 0x033B, + 0x033D, 0x0347, 0x0355, 0x0359, 0x035B, 0x035F, 0x036D, 0x0371, + 0x0373, 0x0377, 0x038B, 0x038F, 0x0397, 0x03A1, 0x03A9, 0x03AD, + 0x03B3, 0x03B9, 0x03C7, 0x03CB, 0x03D1, 0x03D7, 0x03DF, 0x03E5, + 0x03F1, 0x03F5, 0x03FB, 0x03FD, 0x0407, 0x0409, 0x040F, 0x0419, + 0x041B, 0x0425, 0x0427, 0x042D, 0x043F, 0x0443, 0x0445, 0x0449, + 0x044F, 0x0455, 0x045D, 0x0463, 0x0469, 0x047F, 0x0481, 0x048B, + + 0x0493, 0x049D, 0x04A3, 0x04A9, 0x04B1, 0x04BD, 0x04C1, 0x04C7, + 0x04CD, 0x04CF, 0x04D5, 0x04E1, 0x04EB, 0x04FD, 0x04FF, 0x0503, + 0x0509, 0x050B, 0x0511, 0x0515, 0x0517, 0x051B, 0x0527, 0x0529, + 0x052F, 0x0551, 0x0557, 0x055D, 0x0565, 0x0577, 0x0581, 0x058F, + 0x0593, 0x0595, 0x0599, 0x059F, 0x05A7, 0x05AB, 0x05AD, 0x05B3, + 0x05BF, 0x05C9, 0x05CB, 0x05CF, 0x05D1, 0x05D5, 0x05DB, 0x05E7, + 0x05F3, 0x05FB, 0x0607, 0x060D, 0x0611, 0x0617, 0x061F, 0x0623, + 0x062B, 0x062F, 0x063D, 0x0641, 0x0647, 0x0649, 0x064D, 0x0653 +}; + +int fp_isprime(fp_int *a) +{ + fp_int b; + fp_digit d; + int r, res; + + /* do trial division */ + for (r = 0; r < 256; r++) { + fp_mod_d(a, primes[r], &d); + if (d == 0) { + return FP_NO; + } + } + + /* now do 8 miller rabins */ + fp_init(&b); + for (r = 0; r < 8; r++) { + fp_set(&b, primes[r]); + fp_prime_miller_rabin(a, &b, &res); + if (res == FP_NO) { + return FP_NO; + } + } + return FP_YES; +} + + +/* c = [a, b] */ +void fp_lcm(fp_int *a, fp_int *b, fp_int *c) +{ + fp_int t1, t2; + + fp_init(&t1); + fp_init(&t2); + fp_gcd(a, b, &t1); + if (fp_cmp_mag(a, b) == FP_GT) { + fp_div(a, &t1, &t2, NULL); + fp_mul(b, &t2, c); + } else { + fp_div(b, &t1, &t2, NULL); + fp_mul(a, &t2, c); + } +} + + +static const int lnz[16] = { + 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0 +}; + +/* Counts the number of lsbs which are zero before the first zero bit */ +int fp_cnt_lsb(fp_int *a) +{ + int x; + fp_digit q, qq; + + /* easy out */ + if (fp_iszero(a) == 1) { + return 0; + } + + /* scan lower digits until non-zero */ + for (x = 0; x < a->used && a->dp[x] == 0; x++); + q = a->dp[x]; + x *= DIGIT_BIT; + + /* now scan this digit until a 1 is found */ + if ((q & 1) == 0) { + do { + qq = q & 15; + x += lnz[qq]; + q >>= 4; + } while (qq == 0); + } + return x; +} + + +/* c = (a, b) */ +void fp_gcd(fp_int *a, fp_int *b, fp_int *c) +{ + fp_int u, v, r; + + /* either zero than gcd is the largest */ + if (fp_iszero (a) == 1 && fp_iszero (b) == 0) { + fp_abs (b, c); + return; + } + if (fp_iszero (a) == 0 && fp_iszero (b) == 1) { + fp_abs (a, c); + return; + } + + /* optimized. At this point if a == 0 then + * b must equal zero too + */ + if (fp_iszero (a) == 1) { + fp_zero(c); + return; + } + + /* sort inputs */ + if (fp_cmp_mag(a, b) != FP_LT) { + fp_init_copy(&u, a); + fp_init_copy(&v, b); + } else { + fp_init_copy(&u, b); + fp_init_copy(&v, a); + } + + fp_zero(&r); + while (fp_iszero(&v) == FP_NO) { + fp_mod(&u, &v, &r); + fp_copy(&v, &u); + fp_copy(&r, &v); + } + fp_copy(&u, c); +} + +#endif /* CYASSL_KEY_GEN */ + + +#ifdef HAVE_ECC + +/* chars used in radix conversions */ +const char *fp_s_rmap = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz+/"; + +/* c = a + b */ +void fp_add_d(fp_int *a, fp_digit b, fp_int *c) +{ + fp_int tmp; + fp_set(&tmp, b); + fp_add(a,&tmp,c); +} + + +int fp_read_radix(fp_int *a, const char *str, int radix) +{ + int y, neg; + char ch; + + /* make sure the radix is ok */ + if (radix < 2 || radix > 64) { + return FP_VAL; + } + + /* if the leading digit is a + * minus set the sign to negative. + */ + if (*str == '-') { + ++str; + neg = FP_NEG; + } else { + neg = FP_ZPOS; + } + + /* set the integer to the default of zero */ + fp_zero (a); + + /* process each digit of the string */ + while (*str) { + /* if the radix < 36 the conversion is case insensitive + * this allows numbers like 1AB and 1ab to represent the same value + * [e.g. in hex] + */ + ch = (char) ((radix < 36) ? XTOUPPER(*str) : *str); + for (y = 0; y < 64; y++) { + if (ch == fp_s_rmap[y]) { + break; + } + } + + /* if the char was found in the map + * and is less than the given radix add it + * to the number, otherwise exit the loop. + */ + if (y < radix) { + fp_mul_d (a, (fp_digit) radix, a); + fp_add_d (a, (fp_digit) y, a); + } else { + break; + } + ++str; + } + + /* set the sign only if a != 0 */ + if (fp_iszero(a) != FP_YES) { + a->sign = neg; + } + return FP_OKAY; +} + +/* fast math conversion */ +int mp_read_radix(mp_int *a, const char *str, int radix) +{ + return fp_read_radix(a, str, radix); +} + +/* fast math conversion */ +int mp_iszero(mp_int* a) +{ + return fp_iszero(a); +} + +/* fast math conversion */ +int mp_set(fp_int *a, fp_digit b) +{ + fp_set(a,b); + return MP_OKAY; +} + +/* fast math conversion */ +int mp_sqr(fp_int *A, fp_int *B) +{ + fp_sqr(A, B); + return MP_OKAY; +} + +/* fast math conversion */ +int mp_montgomery_reduce(fp_int *a, fp_int *m, fp_digit mp) +{ + fp_montgomery_reduce(a, m, mp); + return MP_OKAY; +} + + +/* fast math conversion */ +int mp_montgomery_setup(fp_int *a, fp_digit *rho) +{ + return fp_montgomery_setup(a, rho); +} + +/* fast math conversion */ +int mp_isodd(mp_int* a) +{ + return fp_isodd(a); +} + + +int mp_div_2(fp_int * a, fp_int * b) +{ + fp_div_2(a, b); + return MP_OKAY; +} + +#endif /* HAVE_ECC */ + +#endif /* USE_FAST_MATH */ -- cgit v1.2.3-54-g00ecf