From 539364846a89987ac2679988653f50332cb91d26 Mon Sep 17 00:00:00 2001 From: "madmaxoft@gmail.com" Date: Thu, 30 Aug 2012 21:06:13 +0000 Subject: Implemented 1.3.2 protocol encryption using CryptoPP, up to Client Status packet (http://wiki.vg/Protocol_FAQ step 14) git-svn-id: http://mc-server.googlecode.com/svn/trunk@808 0a769ca7-a7f5-676a-18bf-c427514a06d6 --- CryptoPP/dmac.h | 93 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 93 insertions(+) create mode 100644 CryptoPP/dmac.h (limited to 'CryptoPP/dmac.h') diff --git a/CryptoPP/dmac.h b/CryptoPP/dmac.h new file mode 100644 index 000000000..80b54ac2f --- /dev/null +++ b/CryptoPP/dmac.h @@ -0,0 +1,93 @@ +#ifndef CRYPTOPP_DMAC_H +#define CRYPTOPP_DMAC_H + +#include "cbcmac.h" + +NAMESPACE_BEGIN(CryptoPP) + +//! _ +template +class CRYPTOPP_NO_VTABLE DMAC_Base : public SameKeyLengthAs, public MessageAuthenticationCode +{ +public: + static std::string StaticAlgorithmName() {return std::string("DMAC(") + T::StaticAlgorithmName() + ")";} + + CRYPTOPP_CONSTANT(DIGESTSIZE=T::BLOCKSIZE) + + DMAC_Base() {} + + void UncheckedSetKey(const byte *key, unsigned int length, const NameValuePairs ¶ms); + void Update(const byte *input, size_t length); + void TruncatedFinal(byte *mac, size_t size); + unsigned int DigestSize() const {return DIGESTSIZE;} + +private: + byte *GenerateSubKeys(const byte *key, size_t keylength); + + size_t m_subkeylength; + SecByteBlock m_subkeys; + CBC_MAC m_mac1; + typename T::Encryption m_f2; + unsigned int m_counter; +}; + +//! DMAC +/*! Based on "CBC MAC for Real-Time Data Sources" by Erez Petrank + and Charles Rackoff. T should be a class derived from BlockCipherDocumentation. +*/ +template +class DMAC : public MessageAuthenticationCodeFinal > +{ +public: + DMAC() {} + DMAC(const byte *key, size_t length=DMAC_Base::DEFAULT_KEYLENGTH) + {this->SetKey(key, length);} +}; + +template +void DMAC_Base::UncheckedSetKey(const byte *key, unsigned int length, const NameValuePairs ¶ms) +{ + m_subkeylength = T::StaticGetValidKeyLength(T::BLOCKSIZE); + m_subkeys.resize(2*UnsignedMin((unsigned int)T::BLOCKSIZE, m_subkeylength)); + m_mac1.SetKey(GenerateSubKeys(key, length), m_subkeylength, params); + m_f2.SetKey(m_subkeys+m_subkeys.size()/2, m_subkeylength, params); + m_counter = 0; + m_subkeys.resize(0); +} + +template +void DMAC_Base::Update(const byte *input, size_t length) +{ + m_mac1.Update(input, length); + m_counter = (unsigned int)((m_counter + length) % T::BLOCKSIZE); +} + +template +void DMAC_Base::TruncatedFinal(byte *mac, size_t size) +{ + ThrowIfInvalidTruncatedSize(size); + + byte pad[T::BLOCKSIZE]; + byte padByte = byte(T::BLOCKSIZE-m_counter); + memset(pad, padByte, padByte); + m_mac1.Update(pad, padByte); + m_mac1.TruncatedFinal(mac, size); + m_f2.ProcessBlock(mac); + + m_counter = 0; // reset for next message +} + +template +byte *DMAC_Base::GenerateSubKeys(const byte *key, size_t keylength) +{ + typename T::Encryption cipher(key, keylength); + memset(m_subkeys, 0, m_subkeys.size()); + cipher.ProcessBlock(m_subkeys); + m_subkeys[m_subkeys.size()/2 + T::BLOCKSIZE - 1] = 1; + cipher.ProcessBlock(m_subkeys+m_subkeys.size()/2); + return m_subkeys; +} + +NAMESPACE_END + +#endif -- cgit v1.2.3