Blob
1 #include "os.h"2 #include <mp.h>4 #define iseven(a) (((a)->p[0] & 1) == 0)6 /* use extended gcd to find the multiplicative inverse */7 /* res = b**-1 mod m */8 void9 mpinvert(mpint *b, mpint *m, mpint *res)10 {11 mpint *dc1, *dc2; /* don't care */13 dc1 = mpnew(0);14 dc2 = mpnew(0);15 mpextendedgcd(b, m, dc1, res, dc2);16 if(mpcmp(dc1, mpone) != 0)17 abort();18 mpmod(res, m, res);19 mpfree(dc1);20 mpfree(dc2);21 }