/* * IF Scheme * (C) 1999-2007 Jack Lloyd * * Distributed under the terms of the Botan license */ #include <botan/if_algo.h> #include <botan/numthry.h> #include <botan/der_enc.h> #include <botan/ber_dec.h> namespace Botan { AlgorithmIdentifier IF_Scheme_PublicKey::algorithm_identifier() const { return AlgorithmIdentifier(get_oid(), AlgorithmIdentifier::USE_NULL_PARAM); } MemoryVector<byte> IF_Scheme_PublicKey::x509_subject_public_key() const { return DER_Encoder() .start_cons(SEQUENCE) .encode(n) .encode(e) .end_cons() .get_contents(); } IF_Scheme_PublicKey::IF_Scheme_PublicKey(const AlgorithmIdentifier&, const MemoryRegion<byte>& key_bits) { BER_Decoder(key_bits) .start_cons(SEQUENCE) .decode(n) .decode(e) .verify_end() .end_cons(); } /* * Check IF Scheme Public Parameters */ bool IF_Scheme_PublicKey::check_key(RandomNumberGenerator&, bool) const { if(n < 35 || n.is_even() || e < 2) return false; return true; } MemoryVector<byte> IF_Scheme_PrivateKey::pkcs8_private_key() const { return DER_Encoder() .start_cons(SEQUENCE) .encode(static_cast<u32bit>(0)) .encode(n) .encode(e) .encode(d) .encode(p) .encode(q) .encode(d1) .encode(d2) .encode(c) .end_cons() .get_contents(); } IF_Scheme_PrivateKey::IF_Scheme_PrivateKey(RandomNumberGenerator& rng, const AlgorithmIdentifier&, const MemoryRegion<byte>& key_bits) { BER_Decoder(key_bits) .start_cons(SEQUENCE) .decode_and_check<u32bit>(0, "Unknown PKCS #1 key format version") .decode(n) .decode(e) .decode(d) .decode(p) .decode(q) .decode(d1) .decode(d2) .decode(c) .end_cons(); load_check(rng); } IF_Scheme_PrivateKey::IF_Scheme_PrivateKey(RandomNumberGenerator& rng, const BigInt& prime1, const BigInt& prime2, const BigInt& exp, const BigInt& d_exp, const BigInt& mod) { p = prime1; q = prime2; e = exp; d = d_exp; n = mod.is_nonzero() ? mod : p * q; if(d == 0) { BigInt inv_for_d = lcm(p - 1, q - 1); if(e.is_even()) inv_for_d >>= 1; d = inverse_mod(e, inv_for_d); } d1 = d % (p - 1); d2 = d % (q - 1); c = inverse_mod(q, p); load_check(rng); } /* * Check IF Scheme Private Parameters */ bool IF_Scheme_PrivateKey::check_key(RandomNumberGenerator& rng, bool strong) const { if(n < 35 || n.is_even() || e < 2 || d < 2 || p < 3 || q < 3 || p*q != n) return false; if(!strong) return true; if(d1 != d % (p - 1) || d2 != d % (q - 1) || c != inverse_mod(q, p)) return false; if(!check_prime(p, rng) || !check_prime(q, rng)) return false; return true; } }