kPriv.dp = d % (kPriv.p - 1);
kPriv.dq = d % (kPriv.q - 1);
- // qInv = q^-1 (mod p)
+ // qInv = q^-1 (mod p).
mpz_invert(kPriv.qInv.get_mpz_t(), kPriv.q.get_mpz_t(), kPriv.p.get_mpz_t());
return make_pair(kPub, kPriv);
}
mpz_class RsaCrt::sign(const mpz_class& m, const KeyPriv& kPriv)
+{
+ return sign(m, kPriv, false);
+}
+
+mpz_class RsaCrt::signWithFaultySp(const mpz_class& m, const KeyPriv& kPriv)
+{
+ return sign(m, kPriv, true);
+}
+
+mpz_class RsaCrt::sign(const mpz_class& m, const KeyPriv& kPriv, bool withError)
{
mpz_class sp, sq;
mpz_powm_sec(sp.get_mpz_t(), m.get_mpz_t(), kPriv.dp.get_mpz_t(), kPriv.p.get_mpz_t());
mpz_powm_sec(sq.get_mpz_t(), m.get_mpz_t(), kPriv.dq.get_mpz_t(), kPriv.q.get_mpz_t());
+ if (withError)
+ mpz_combit(sp.get_mpz_t(), 42); // Flip the fourty second bit.
+
return sq + ((kPriv.qInv * (sp - sq)) % kPriv.p) * kPriv.q;
}