/* hac 14.61, pp608 */ int mp_invmod(mp_int * a, mp_int * b, mp_int * c) { /* b cannot be negative */ if (b->sign == MP_NEG || mp_iszero(b) == 1) { return MP_VAL; } #ifdef BN_FAST_MP_INVMOD_C /* if the modulus is odd we can use a faster routine instead */ if (mp_isodd(b) == 1) { return fast_mp_invmod(a, b, c); } #endif #ifdef BN_MP_INVMOD_SLOW_C return mp_invmod_slow(a, b, c); #endif return MP_VAL; }
/* hac 14.61, pp608 */ int mp_invmod(const mp_int *a, const mp_int *b, mp_int *c) { /* b cannot be negative and has to be >1 */ if ((b->sign == MP_NEG) || (mp_cmp_d(b, 1uL) != MP_GT)) { return MP_VAL; } #ifdef BN_FAST_MP_INVMOD_C /* if the modulus is odd we can use a faster routine instead */ if ((mp_isodd(b) == MP_YES)) { return fast_mp_invmod(a, b, c); } #endif #ifdef BN_MP_INVMOD_SLOW_C return mp_invmod_slow(a, b, c); #else return MP_VAL; #endif }