ext-cryptopp/pkcspad.cpp

155 lines
6.6 KiB
C++

// pkcspad.cpp - written and placed in the public domain by Wei Dai
#include "pch.h"
#ifndef CRYPTOPP_PKCSPAD_CPP // SunCC workaround: compiler could cause this file to be included twice
#define CRYPTOPP_PKCSPAD_CPP
#include "pkcspad.h"
#include "emsa2.h"
#include "misc.h"
#include "trap.h"
NAMESPACE_BEGIN(CryptoPP)
// More in dll.cpp. Typedef/cast change due to Clang, http://github.com/weidai11/cryptopp/issues/300
template<> const byte PKCS_DigestDecoration<Weak1::MD2>::decoration[] = {0x30,0x20,0x30,0x0c,0x06,0x08,0x2a,0x86,0x48,0x86,0xf7,0x0d,0x02,0x02,0x05,0x00,0x04,0x10};
template<> const unsigned int PKCS_DigestDecoration<Weak1::MD2>::length = (unsigned int)sizeof(PKCS_DigestDecoration<Weak1::MD2>::decoration);
template<> const byte PKCS_DigestDecoration<Weak1::MD5>::decoration[] = {0x30,0x20,0x30,0x0c,0x06,0x08,0x2a,0x86,0x48,0x86,0xf7,0x0d,0x02,0x05,0x05,0x00,0x04,0x10};
template<> const unsigned int PKCS_DigestDecoration<Weak1::MD5>::length = (unsigned int)sizeof(PKCS_DigestDecoration<Weak1::MD5>::decoration);
template<> const byte PKCS_DigestDecoration<RIPEMD160>::decoration[] = {0x30,0x21,0x30,0x09,0x06,0x05,0x2b,0x24,0x03,0x02,0x01,0x05,0x00,0x04,0x14};
template<> const unsigned int PKCS_DigestDecoration<RIPEMD160>::length = (unsigned int)sizeof(PKCS_DigestDecoration<RIPEMD160>::decoration);
template<> const byte PKCS_DigestDecoration<Tiger>::decoration[] = {0x30,0x29,0x30,0x0D,0x06,0x09,0x2B,0x06,0x01,0x04,0x01,0xDA,0x47,0x0C,0x02,0x05,0x00,0x04,0x18};
template<> const unsigned int PKCS_DigestDecoration<Tiger>::length = (unsigned int)sizeof(PKCS_DigestDecoration<Tiger>::decoration);
// Inclusion based on DLL due to Clang, http://github.com/weidai11/cryptopp/issues/300
#ifndef CRYPTOPP_IS_DLL
template<> const byte PKCS_DigestDecoration<SHA1>::decoration[] = {0x30,0x21,0x30,0x09,0x06,0x05,0x2B,0x0E,0x03,0x02,0x1A,0x05,0x00,0x04,0x14};
template<> const unsigned int PKCS_DigestDecoration<SHA1>::length = (unsigned int)sizeof(PKCS_DigestDecoration<SHA1>::decoration);
template<> const byte PKCS_DigestDecoration<SHA224>::decoration[] = {0x30,0x2d,0x30,0x0d,0x06,0x09,0x60,0x86,0x48,0x01,0x65,0x03,0x04,0x02,0x04,0x05,0x00,0x04,0x1c};
template<> const unsigned int PKCS_DigestDecoration<SHA224>::length = (unsigned int)sizeof(PKCS_DigestDecoration<SHA224>::decoration);
template<> const byte PKCS_DigestDecoration<SHA256>::decoration[] = {0x30,0x31,0x30,0x0d,0x06,0x09,0x60,0x86,0x48,0x01,0x65,0x03,0x04,0x02,0x01,0x05,0x00,0x04,0x20};
template<> const unsigned int PKCS_DigestDecoration<SHA256>::length = (unsigned int)sizeof(PKCS_DigestDecoration<SHA256>::decoration);
template<> const byte PKCS_DigestDecoration<SHA384>::decoration[] = {0x30,0x41,0x30,0x0d,0x06,0x09,0x60,0x86,0x48,0x01,0x65,0x03,0x04,0x02,0x02,0x05,0x00,0x04,0x30};
template<> const unsigned int PKCS_DigestDecoration<SHA384>::length = (unsigned int)sizeof(PKCS_DigestDecoration<SHA384>::decoration);
template<> const byte PKCS_DigestDecoration<SHA512>::decoration[] = {0x30,0x51,0x30,0x0d,0x06,0x09,0x60,0x86,0x48,0x01,0x65,0x03,0x04,0x02,0x03,0x05,0x00,0x04,0x40};
template<> const unsigned int PKCS_DigestDecoration<SHA512>::length = (unsigned int)sizeof(PKCS_DigestDecoration<SHA512>::decoration);
template<> const byte EMSA2HashId<SHA1>::id = 0x33;
template<> const byte EMSA2HashId<SHA224>::id = 0x38;
template<> const byte EMSA2HashId<SHA256>::id = 0x34;
template<> const byte EMSA2HashId<SHA384>::id = 0x36;
template<> const byte EMSA2HashId<SHA512>::id = 0x35;
#endif
size_t PKCS_EncryptionPaddingScheme::MaxUnpaddedLength(size_t paddedLength) const
{
return SaturatingSubtract(paddedLength/8, 10U);
}
void PKCS_EncryptionPaddingScheme::Pad(RandomNumberGenerator& rng, const byte *input, size_t inputLen, byte *pkcsBlock, size_t pkcsBlockLen, const NameValuePairs& parameters) const
{
CRYPTOPP_UNUSED(parameters);
CRYPTOPP_ASSERT (inputLen <= MaxUnpaddedLength(pkcsBlockLen)); // this should be checked by caller
// convert from bit length to byte length
if (pkcsBlockLen % 8 != 0)
{
pkcsBlock[0] = 0;
pkcsBlock++;
}
pkcsBlockLen /= 8;
pkcsBlock[0] = 2; // block type 2
// pad with non-zero random bytes
for (unsigned i = 1; i < pkcsBlockLen-inputLen-1; i++)
pkcsBlock[i] = (byte)rng.GenerateWord32(1, 0xff);
pkcsBlock[pkcsBlockLen-inputLen-1] = 0; // separator
memcpy(pkcsBlock+pkcsBlockLen-inputLen, input, inputLen);
}
DecodingResult PKCS_EncryptionPaddingScheme::Unpad(const byte *pkcsBlock, size_t pkcsBlockLen, byte *output, const NameValuePairs& parameters) const
{
CRYPTOPP_UNUSED(parameters);
bool invalid = false;
size_t maxOutputLen = MaxUnpaddedLength(pkcsBlockLen);
// convert from bit length to byte length
if (pkcsBlockLen % 8 != 0)
{
invalid = (pkcsBlock[0] != 0) || invalid;
pkcsBlock++;
}
pkcsBlockLen /= 8;
// Require block type 2.
invalid = (pkcsBlock[0] != 2) || invalid;
// skip past the padding until we find the separator
size_t i=1;
while (i<pkcsBlockLen && pkcsBlock[i++]) { // null body
}
CRYPTOPP_ASSERT(i==pkcsBlockLen || pkcsBlock[i-1]==0);
size_t outputLen = pkcsBlockLen - i;
invalid = (outputLen > maxOutputLen) || invalid;
if (invalid)
return DecodingResult();
memcpy (output, pkcsBlock+i, outputLen);
return DecodingResult(outputLen);
}
// ********************************************************
#ifndef CRYPTOPP_IMPORTS
void PKCS1v15_SignatureMessageEncodingMethod::ComputeMessageRepresentative(RandomNumberGenerator &rng,
const byte *recoverableMessage, size_t recoverableMessageLength,
HashTransformation &hash, HashIdentifier hashIdentifier, bool messageEmpty,
byte *representative, size_t representativeBitLength) const
{
CRYPTOPP_UNUSED(rng), CRYPTOPP_UNUSED(recoverableMessage), CRYPTOPP_UNUSED(recoverableMessageLength);
CRYPTOPP_UNUSED(messageEmpty), CRYPTOPP_UNUSED(hashIdentifier);
CRYPTOPP_ASSERT(representativeBitLength >= MinRepresentativeBitLength(hashIdentifier.second, hash.DigestSize()));
size_t pkcsBlockLen = representativeBitLength;
// convert from bit length to byte length
if (pkcsBlockLen % 8 != 0)
{
representative[0] = 0;
representative++;
}
pkcsBlockLen /= 8;
representative[0] = 1; // block type 1
unsigned int digestSize = hash.DigestSize();
byte *pPadding = representative + 1;
byte *pDigest = representative + pkcsBlockLen - digestSize;
byte *pHashId = pDigest - hashIdentifier.second;
byte *pSeparator = pHashId - 1;
// pad with 0xff
memset(pPadding, 0xff, pSeparator-pPadding);
*pSeparator = 0;
memcpy(pHashId, hashIdentifier.first, hashIdentifier.second);
hash.Final(pDigest);
}
#endif
NAMESPACE_END
#endif