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author | Matthieu Patou <mat@matws.net> | 2010-08-15 18:31:28 +0400 |
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committer | Andrew Bartlett <abartlet@samba.org> | 2010-10-03 01:15:04 +0000 |
commit | ab6e3fce040f9ad27cbce44e9038a24f15b601c8 (patch) | |
tree | ab99a431c9610927b5d0d26335d2712b509fd6dc /source4/heimdal/lib/hcrypto/libtommath/bn_mp_toom_mul.c | |
parent | 197a1514d62494cc8b862d169c841a26e04b8925 (diff) | |
download | samba-ab6e3fce040f9ad27cbce44e9038a24f15b601c8.tar.gz samba-ab6e3fce040f9ad27cbce44e9038a24f15b601c8.tar.bz2 samba-ab6e3fce040f9ad27cbce44e9038a24f15b601c8.zip |
s4:heimdal: import lorikeet-heimdal-201009250123 (commit 42cabfb5b683dbcb97d583c397b897507689e382)
I based this on Matthieu's import of lorikeet-heimdal, and then
updated it to this commit.
Andrew Bartlett
Diffstat (limited to 'source4/heimdal/lib/hcrypto/libtommath/bn_mp_toom_mul.c')
-rw-r--r-- | source4/heimdal/lib/hcrypto/libtommath/bn_mp_toom_mul.c | 284 |
1 files changed, 284 insertions, 0 deletions
diff --git a/source4/heimdal/lib/hcrypto/libtommath/bn_mp_toom_mul.c b/source4/heimdal/lib/hcrypto/libtommath/bn_mp_toom_mul.c new file mode 100644 index 0000000000..ad5d9e9b64 --- /dev/null +++ b/source4/heimdal/lib/hcrypto/libtommath/bn_mp_toom_mul.c @@ -0,0 +1,284 @@ +#include <tommath.h> +#ifdef BN_MP_TOOM_MUL_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://libtom.org + */ + +/* multiplication using the Toom-Cook 3-way algorithm + * + * Much more complicated than Karatsuba but has a lower + * asymptotic running time of O(N**1.464). This algorithm is + * only particularly useful on VERY large inputs + * (we're talking 1000s of digits here...). +*/ +int mp_toom_mul(mp_int *a, mp_int *b, mp_int *c) +{ + mp_int w0, w1, w2, w3, w4, tmp1, tmp2, a0, a1, a2, b0, b1, b2; + int res, B; + + /* init temps */ + if ((res = mp_init_multi(&w0, &w1, &w2, &w3, &w4, + &a0, &a1, &a2, &b0, &b1, + &b2, &tmp1, &tmp2, NULL)) != MP_OKAY) { + return res; + } + + /* B */ + B = MIN(a->used, b->used) / 3; + + /* a = a2 * B**2 + a1 * B + a0 */ + if ((res = mp_mod_2d(a, DIGIT_BIT * B, &a0)) != MP_OKAY) { + goto ERR; + } + + if ((res = mp_copy(a, &a1)) != MP_OKAY) { + goto ERR; + } + mp_rshd(&a1, B); + mp_mod_2d(&a1, DIGIT_BIT * B, &a1); + + if ((res = mp_copy(a, &a2)) != MP_OKAY) { + goto ERR; + } + mp_rshd(&a2, B*2); + + /* b = b2 * B**2 + b1 * B + b0 */ + if ((res = mp_mod_2d(b, DIGIT_BIT * B, &b0)) != MP_OKAY) { + goto ERR; + } + + if ((res = mp_copy(b, &b1)) != MP_OKAY) { + goto ERR; + } + mp_rshd(&b1, B); + mp_mod_2d(&b1, DIGIT_BIT * B, &b1); + + if ((res = mp_copy(b, &b2)) != MP_OKAY) { + goto ERR; + } + mp_rshd(&b2, B*2); + + /* w0 = a0*b0 */ + if ((res = mp_mul(&a0, &b0, &w0)) != MP_OKAY) { + goto ERR; + } + + /* w4 = a2 * b2 */ + if ((res = mp_mul(&a2, &b2, &w4)) != MP_OKAY) { + goto ERR; + } + + /* w1 = (a2 + 2(a1 + 2a0))(b2 + 2(b1 + 2b0)) */ + if ((res = mp_mul_2(&a0, &tmp1)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_add(&tmp1, &a1, &tmp1)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_mul_2(&tmp1, &tmp1)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_add(&tmp1, &a2, &tmp1)) != MP_OKAY) { + goto ERR; + } + + if ((res = mp_mul_2(&b0, &tmp2)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_add(&tmp2, &b1, &tmp2)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_mul_2(&tmp2, &tmp2)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_add(&tmp2, &b2, &tmp2)) != MP_OKAY) { + goto ERR; + } + + if ((res = mp_mul(&tmp1, &tmp2, &w1)) != MP_OKAY) { + goto ERR; + } + + /* w3 = (a0 + 2(a1 + 2a2))(b0 + 2(b1 + 2b2)) */ + if ((res = mp_mul_2(&a2, &tmp1)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_add(&tmp1, &a1, &tmp1)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_mul_2(&tmp1, &tmp1)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_add(&tmp1, &a0, &tmp1)) != MP_OKAY) { + goto ERR; + } + + if ((res = mp_mul_2(&b2, &tmp2)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_add(&tmp2, &b1, &tmp2)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_mul_2(&tmp2, &tmp2)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_add(&tmp2, &b0, &tmp2)) != MP_OKAY) { + goto ERR; + } + + if ((res = mp_mul(&tmp1, &tmp2, &w3)) != MP_OKAY) { + goto ERR; + } + + + /* w2 = (a2 + a1 + a0)(b2 + b1 + b0) */ + if ((res = mp_add(&a2, &a1, &tmp1)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_add(&tmp1, &a0, &tmp1)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_add(&b2, &b1, &tmp2)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_add(&tmp2, &b0, &tmp2)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_mul(&tmp1, &tmp2, &w2)) != MP_OKAY) { + goto ERR; + } + + /* now solve the matrix + + 0 0 0 0 1 + 1 2 4 8 16 + 1 1 1 1 1 + 16 8 4 2 1 + 1 0 0 0 0 + + using 12 subtractions, 4 shifts, + 2 small divisions and 1 small multiplication + */ + + /* r1 - r4 */ + if ((res = mp_sub(&w1, &w4, &w1)) != MP_OKAY) { + goto ERR; + } + /* r3 - r0 */ + if ((res = mp_sub(&w3, &w0, &w3)) != MP_OKAY) { + goto ERR; + } + /* r1/2 */ + if ((res = mp_div_2(&w1, &w1)) != MP_OKAY) { + goto ERR; + } + /* r3/2 */ + if ((res = mp_div_2(&w3, &w3)) != MP_OKAY) { + goto ERR; + } + /* r2 - r0 - r4 */ + if ((res = mp_sub(&w2, &w0, &w2)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_sub(&w2, &w4, &w2)) != MP_OKAY) { + goto ERR; + } + /* r1 - r2 */ + if ((res = mp_sub(&w1, &w2, &w1)) != MP_OKAY) { + goto ERR; + } + /* r3 - r2 */ + if ((res = mp_sub(&w3, &w2, &w3)) != MP_OKAY) { + goto ERR; + } + /* r1 - 8r0 */ + if ((res = mp_mul_2d(&w0, 3, &tmp1)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_sub(&w1, &tmp1, &w1)) != MP_OKAY) { + goto ERR; + } + /* r3 - 8r4 */ + if ((res = mp_mul_2d(&w4, 3, &tmp1)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_sub(&w3, &tmp1, &w3)) != MP_OKAY) { + goto ERR; + } + /* 3r2 - r1 - r3 */ + if ((res = mp_mul_d(&w2, 3, &w2)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_sub(&w2, &w1, &w2)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_sub(&w2, &w3, &w2)) != MP_OKAY) { + goto ERR; + } + /* r1 - r2 */ + if ((res = mp_sub(&w1, &w2, &w1)) != MP_OKAY) { + goto ERR; + } + /* r3 - r2 */ + if ((res = mp_sub(&w3, &w2, &w3)) != MP_OKAY) { + goto ERR; + } + /* r1/3 */ + if ((res = mp_div_3(&w1, &w1, NULL)) != MP_OKAY) { + goto ERR; + } + /* r3/3 */ + if ((res = mp_div_3(&w3, &w3, NULL)) != MP_OKAY) { + goto ERR; + } + + /* at this point shift W[n] by B*n */ + if ((res = mp_lshd(&w1, 1*B)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_lshd(&w2, 2*B)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_lshd(&w3, 3*B)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_lshd(&w4, 4*B)) != MP_OKAY) { + goto ERR; + } + + if ((res = mp_add(&w0, &w1, c)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_add(&w2, &w3, &tmp1)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_add(&w4, &tmp1, &tmp1)) != MP_OKAY) { + goto ERR; + } + if ((res = mp_add(&tmp1, c, c)) != MP_OKAY) { + goto ERR; + } + +ERR: + mp_clear_multi(&w0, &w1, &w2, &w3, &w4, + &a0, &a1, &a2, &b0, &b1, + &b2, &tmp1, &tmp2, NULL); + return res; +} + +#endif + +/* $Source: /cvs/libtom/libtommath/bn_mp_toom_mul.c,v $ */ +/* $Revision: 1.4 $ */ +/* $Date: 2006/12/28 01:25:13 $ */ |