X-Git-Url: http://git.euphorik.ch/?a=blobdiff_plain;f=src%2FRsaCrt.cpp;h=869fce549eb57dc64c913a8bcc5601fa2388c843;hb=5b2785dd710151d81e6f6af4fd6ae48521068e41;hp=43f0b972bac7392a8f5b92395417c6bc811fa4f5;hpb=7975d02c6c1ee679a236087e86955c086f1a9a8e;p=crypto_lab3.git diff --git a/src/RsaCrt.cpp b/src/RsaCrt.cpp index 43f0b97..869fce5 100644 --- a/src/RsaCrt.cpp +++ b/src/RsaCrt.cpp @@ -1 +1,56 @@ #include "RsaCrt.h" + +using namespace std; + +#include "Rand.h" +#include "Utils.h" + +pair RsaCrt::generateRSAKeys(uint exponent, uint keySizeBits) +{ + mpz_class phi, d; + Rsa::KeyPub kPub; + KeyPriv kPriv; + + do + { + kPub.e = exponent; + kPriv.p = Rand::randPrime(keySizeBits / 2); + kPriv.q = Rand::randPrime(keySizeBits / 2); + + kPub.n = kPriv.p * kPriv.q; + phi = (kPriv.p - 1) * (kPriv.q - 1); + + // d = e^-1 (mode phi). + } while (mpz_invert(d.get_mpz_t(), kPub.e.get_mpz_t(), phi.get_mpz_t()) == 0); + + kPriv.dp = d % (kPriv.p - 1); + kPriv.dq = d % (kPriv.q - 1); + + // 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; +}