From c96694237fff7e2558681000f2ea37b1cc9bb3fa Mon Sep 17 00:00:00 2001 From: orignal Date: Wed, 15 Oct 2014 14:04:23 -0400 Subject: [PATCH] use constants instead magic numbers --- Signature.h | 40 ++++++++++++++++++++++++---------------- 1 file changed, 24 insertions(+), 16 deletions(-) diff --git a/Signature.h b/Signature.h index 3bd99744..fbc02c4e 100644 --- a/Signature.h +++ b/Signature.h @@ -31,23 +31,26 @@ namespace crypto virtual void Sign (CryptoPP::RandomNumberGenerator& rnd, const uint8_t * buf, int len, uint8_t * signature) const = 0; }; + const size_t DSA_PUBLIC_KEY_LENGTH = 128; + const size_t DSA_SIGNATURE_LENGTH = 40; + const size_t DSA_PRIVATE_KEY_LENGTH = DSA_SIGNATURE_LENGTH/2; class DSAVerifier: public Verifier { public: DSAVerifier (const uint8_t * signingKey) { - m_PublicKey.Initialize (dsap, dsaq, dsag, CryptoPP::Integer (signingKey, 128)); + m_PublicKey.Initialize (dsap, dsaq, dsag, CryptoPP::Integer (signingKey, DSA_PUBLIC_KEY_LENGTH)); } bool Verify (const uint8_t * buf, size_t len, const uint8_t * signature) const { CryptoPP::DSA::Verifier verifier (m_PublicKey); - return verifier.VerifyMessage (buf, len, signature, 40); + return verifier.VerifyMessage (buf, len, signature, DSA_SIGNATURE_LENGTH); } - size_t GetPublicKeyLen () const { return 128; }; - size_t GetSignatureLen () const { return 40; }; + size_t GetPublicKeyLen () const { return DSA_PUBLIC_KEY_LENGTH; }; + size_t GetSignatureLen () const { return DSA_SIGNATURE_LENGTH; }; private: @@ -60,7 +63,7 @@ namespace crypto DSASigner (const uint8_t * signingPrivateKey) { - m_PrivateKey.Initialize (dsap, dsaq, dsag, CryptoPP::Integer (signingPrivateKey, 20)); + m_PrivateKey.Initialize (dsap, dsaq, dsag, CryptoPP::Integer (signingPrivateKey, DSA_PRIVATE_KEY_LENGTH)); } void Sign (CryptoPP::RandomNumberGenerator& rnd, const uint8_t * buf, int len, uint8_t * signature) const @@ -80,10 +83,15 @@ namespace crypto CryptoPP::DSA::PublicKey publicKey; privateKey.Initialize (rnd, dsap, dsaq, dsag); privateKey.MakePublicKey (publicKey); - privateKey.GetPrivateExponent ().Encode (signingPrivateKey, 20); - publicKey.GetPublicElement ().Encode (signingPublicKey, 128); + privateKey.GetPrivateExponent ().Encode (signingPrivateKey, DSA_PRIVATE_KEY_LENGTH); + publicKey.GetPublicElement ().Encode (signingPublicKey, DSA_PUBLIC_KEY_LENGTH); } + + const size_t ECDSAP256_PUBLIC_KEY_LENGTH = 64; + const size_t ECDSAP256_PUBLIC_KEY_HALF_LENGTH = ECDSAP256_PUBLIC_KEY_LENGTH/2; + const size_t ECDSAP256_SIGNATURE_LENGTH = 64; + const size_t ECDSAP256_PRIVATE_KEY_LENGTH = ECDSAP256_SIGNATURE_LENGTH/2; class ECDSAP256Verifier: public Verifier { public: @@ -91,18 +99,18 @@ namespace crypto ECDSAP256Verifier (const uint8_t * signingKey) { m_PublicKey.Initialize (CryptoPP::ASN1::secp256r1(), - CryptoPP::ECP::Point (CryptoPP::Integer (signingKey, 32), - CryptoPP::Integer (signingKey + 32, 32))); + CryptoPP::ECP::Point (CryptoPP::Integer (signingKey, ECDSAP256_PUBLIC_KEY_HALF_LENGTH), + CryptoPP::Integer (signingKey + ECDSAP256_PUBLIC_KEY_HALF_LENGTH, ECDSAP256_PUBLIC_KEY_HALF_LENGTH))); } bool Verify (const uint8_t * buf, size_t len, const uint8_t * signature) const { CryptoPP::ECDSA::Verifier verifier (m_PublicKey); - return verifier.VerifyMessage (buf, len, signature, 64); + return verifier.VerifyMessage (buf, len, signature, ECDSAP256_SIGNATURE_LENGTH); } - size_t GetPublicKeyLen () const { return 64; }; - size_t GetSignatureLen () const { return 64; }; + size_t GetPublicKeyLen () const { return ECDSAP256_PUBLIC_KEY_LENGTH; }; + size_t GetSignatureLen () const { return ECDSAP256_SIGNATURE_LENGTH; }; private: @@ -115,7 +123,7 @@ namespace crypto ECDSAP256Signer (const uint8_t * signingPrivateKey) { - m_PrivateKey.Initialize (CryptoPP::ASN1::secp256r1(), CryptoPP::Integer (signingPrivateKey, 32)); + m_PrivateKey.Initialize (CryptoPP::ASN1::secp256r1(), CryptoPP::Integer (signingPrivateKey, ECDSAP256_PRIVATE_KEY_LENGTH)); } void Sign (CryptoPP::RandomNumberGenerator& rnd, const uint8_t * buf, int len, uint8_t * signature) const @@ -135,10 +143,10 @@ namespace crypto CryptoPP::ECDSA::PublicKey publicKey; privateKey.Initialize (rnd, CryptoPP::ASN1::secp256r1()); privateKey.MakePublicKey (publicKey); - privateKey.GetPrivateExponent ().Encode (signingPrivateKey, 32); + privateKey.GetPrivateExponent ().Encode (signingPrivateKey, ECDSAP256_PRIVATE_KEY_LENGTH); auto q = publicKey.GetPublicElement (); - q.x.Encode (signingPublicKey, 32); - q.y.Encode (signingPublicKey + 32, 32); + q.x.Encode (signingPublicKey, ECDSAP256_PUBLIC_KEY_HALF_LENGTH); + q.y.Encode (signingPublicKey + ECDSAP256_PUBLIC_KEY_HALF_LENGTH, ECDSAP256_PUBLIC_KEY_HALF_LENGTH); } } }