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author | jan.nijtmans <nijtmans@users.sourceforge.net> | 2017-09-15 14:44:00 (GMT) |
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committer | jan.nijtmans <nijtmans@users.sourceforge.net> | 2017-09-15 14:44:00 (GMT) |
commit | 30f7e69b182d1267056ee2628a860891f6555aa3 (patch) | |
tree | 4598f9d64ea232476fcf18bbef6bd413444c0c07 /libtommath/bn_mp_jacobi.c | |
parent | b167e2845e3a2d5b2ffe3a877cb19c3f430aeacf (diff) | |
download | tcl-30f7e69b182d1267056ee2628a860891f6555aa3.zip tcl-30f7e69b182d1267056ee2628a860891f6555aa3.tar.gz tcl-30f7e69b182d1267056ee2628a860891f6555aa3.tar.bz2 |
re-format everything through astyle. Taken from libtom/libtommath (pull request [https://github.com/libtom/libtommath/pull/85|85])
Diffstat (limited to 'libtommath/bn_mp_jacobi.c')
-rw-r--r-- | libtommath/bn_mp_jacobi.c | 152 |
1 files changed, 77 insertions, 75 deletions
diff --git a/libtommath/bn_mp_jacobi.c b/libtommath/bn_mp_jacobi.c index 5fc8593..8981393 100644 --- a/libtommath/bn_mp_jacobi.c +++ b/libtommath/bn_mp_jacobi.c @@ -20,95 +20,97 @@ * HAC is wrong here, as the special case of (0 | 1) is not * handled correctly. */ -int mp_jacobi (mp_int * a, mp_int * n, int *c) +int mp_jacobi(mp_int *a, mp_int *n, int *c) { - mp_int a1, p1; - int k, s, r, res; - mp_digit residue; + mp_int a1, p1; + int k, s, r, res; + mp_digit residue; - /* if a < 0 return MP_VAL */ - if (mp_isneg(a) == MP_YES) { - return MP_VAL; - } + /* if a < 0 return MP_VAL */ + if (mp_isneg(a) == MP_YES) { + return MP_VAL; + } - /* if n <= 0 return MP_VAL */ - if (mp_cmp_d(n, 0) != MP_GT) { - return MP_VAL; - } + /* if n <= 0 return MP_VAL */ + if (mp_cmp_d(n, 0) != MP_GT) { + return MP_VAL; + } - /* step 1. handle case of a == 0 */ - if (mp_iszero (a) == MP_YES) { - /* special case of a == 0 and n == 1 */ - if (mp_cmp_d (n, 1) == MP_EQ) { - *c = 1; - } else { - *c = 0; - } - return MP_OKAY; - } + /* step 1. handle case of a == 0 */ + if (mp_iszero(a) == MP_YES) { + /* special case of a == 0 and n == 1 */ + if (mp_cmp_d(n, 1) == MP_EQ) { + *c = 1; + } else { + *c = 0; + } + return MP_OKAY; + } - /* step 2. if a == 1, return 1 */ - if (mp_cmp_d (a, 1) == MP_EQ) { - *c = 1; - return MP_OKAY; - } + /* step 2. if a == 1, return 1 */ + if (mp_cmp_d(a, 1) == MP_EQ) { + *c = 1; + return MP_OKAY; + } - /* default */ - s = 0; + /* default */ + s = 0; - /* step 3. write a = a1 * 2**k */ - if ((res = mp_init_copy (&a1, a)) != MP_OKAY) { - return res; - } + /* step 3. write a = a1 * 2**k */ + if ((res = mp_init_copy(&a1, a)) != MP_OKAY) { + return res; + } - if ((res = mp_init (&p1)) != MP_OKAY) { - goto LBL_A1; - } + if ((res = mp_init(&p1)) != MP_OKAY) { + goto LBL_A1; + } - /* divide out larger power of two */ - k = mp_cnt_lsb(&a1); - if ((res = mp_div_2d(&a1, k, &a1, NULL)) != MP_OKAY) { - goto LBL_P1; - } - - /* step 4. if e is even set s=1 */ - if ((k & 1) == 0) { - s = 1; - } else { - /* else set s=1 if p = 1/7 (mod 8) or s=-1 if p = 3/5 (mod 8) */ - residue = n->dp[0] & 7; + /* divide out larger power of two */ + k = mp_cnt_lsb(&a1); + if ((res = mp_div_2d(&a1, k, &a1, NULL)) != MP_OKAY) { + goto LBL_P1; + } - if ((residue == 1) || (residue == 7)) { + /* step 4. if e is even set s=1 */ + if ((k & 1) == 0) { s = 1; - } else if ((residue == 3) || (residue == 5)) { - s = -1; - } - } + } else { + /* else set s=1 if p = 1/7 (mod 8) or s=-1 if p = 3/5 (mod 8) */ + residue = n->dp[0] & 7; - /* step 5. if p == 3 (mod 4) *and* a1 == 3 (mod 4) then s = -s */ - if ( ((n->dp[0] & 3) == 3) && ((a1.dp[0] & 3) == 3)) { - s = -s; - } + if ((residue == 1) || (residue == 7)) { + s = 1; + } else if ((residue == 3) || (residue == 5)) { + s = -1; + } + } - /* if a1 == 1 we're done */ - if (mp_cmp_d (&a1, 1) == MP_EQ) { - *c = s; - } else { - /* n1 = n mod a1 */ - if ((res = mp_mod (n, &a1, &p1)) != MP_OKAY) { - goto LBL_P1; - } - if ((res = mp_jacobi (&p1, &a1, &r)) != MP_OKAY) { - goto LBL_P1; - } - *c = s * r; - } + /* step 5. if p == 3 (mod 4) *and* a1 == 3 (mod 4) then s = -s */ + if (((n->dp[0] & 3) == 3) && ((a1.dp[0] & 3) == 3)) { + s = -s; + } + + /* if a1 == 1 we're done */ + if (mp_cmp_d(&a1, 1) == MP_EQ) { + *c = s; + } else { + /* n1 = n mod a1 */ + if ((res = mp_mod(n, &a1, &p1)) != MP_OKAY) { + goto LBL_P1; + } + if ((res = mp_jacobi(&p1, &a1, &r)) != MP_OKAY) { + goto LBL_P1; + } + *c = s * r; + } - /* done */ - res = MP_OKAY; -LBL_P1:mp_clear (&p1); -LBL_A1:mp_clear (&a1); - return res; + /* done */ + res = MP_OKAY; +LBL_P1: + mp_clear(&p1); +LBL_A1: + mp_clear(&a1); + return res; } #endif |