00001
00002
00003 #include "pch.h"
00004
00005 #ifndef CRYPTOPP_PKCSPAD_CPP // SunCC workaround: compiler could cause this file to be included twice
00006 #define CRYPTOPP_PKCSPAD_CPP
00007
00008 #include "pkcspad.h"
00009 #include <assert.h>
00010
00011 NAMESPACE_BEGIN(CryptoPP)
00012
00013
00014 template<> const byte PKCS_DigestDecoration<MD2>::decoration[] = {0x30,0x20,0x30,0x0c,0x06,0x08,0x2a,0x86,0x48,0x86,0xf7,0x0d,0x02,0x02,0x05,0x00,0x04,0x10};
00015 template<> const unsigned int PKCS_DigestDecoration<MD2>::length = sizeof(PKCS_DigestDecoration<MD2>::decoration);
00016
00017 template<> const byte PKCS_DigestDecoration<MD5>::decoration[] = {0x30,0x20,0x30,0x0c,0x06,0x08,0x2a,0x86,0x48,0x86,0xf7,0x0d,0x02,0x05,0x05,0x00,0x04,0x10};
00018 template<> const unsigned int PKCS_DigestDecoration<MD5>::length = sizeof(PKCS_DigestDecoration<MD5>::decoration);
00019
00020 template<> const byte PKCS_DigestDecoration<RIPEMD160>::decoration[] = {0x30,0x21,0x30,0x09,0x06,0x05,0x2b,0x24,0x03,0x02,0x01,0x05,0x00,0x04,0x14};
00021 template<> const unsigned int PKCS_DigestDecoration<RIPEMD160>::length = sizeof(PKCS_DigestDecoration<RIPEMD160>::decoration);
00022
00023 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};
00024 template<> const unsigned int PKCS_DigestDecoration<Tiger>::length = sizeof(PKCS_DigestDecoration<Tiger>::decoration);
00025
00026 size_t PKCS_EncryptionPaddingScheme::MaxUnpaddedLength(size_t paddedLength) const
00027 {
00028 return SaturatingSubtract(paddedLength/8, 10U);
00029 }
00030
00031 void PKCS_EncryptionPaddingScheme::Pad(RandomNumberGenerator &rng, const byte *input, size_t inputLen, byte *pkcsBlock, size_t pkcsBlockLen, const NameValuePairs ¶meters) const
00032 {
00033 assert (inputLen <= MaxUnpaddedLength(pkcsBlockLen));
00034
00035
00036 if (pkcsBlockLen % 8 != 0)
00037 {
00038 pkcsBlock[0] = 0;
00039 pkcsBlock++;
00040 }
00041 pkcsBlockLen /= 8;
00042
00043 pkcsBlock[0] = 2;
00044
00045
00046 for (unsigned i = 1; i < pkcsBlockLen-inputLen-1; i++)
00047 pkcsBlock[i] = (byte)rng.GenerateWord32(1, 0xff);
00048
00049 pkcsBlock[pkcsBlockLen-inputLen-1] = 0;
00050 memcpy(pkcsBlock+pkcsBlockLen-inputLen, input, inputLen);
00051 }
00052
00053 DecodingResult PKCS_EncryptionPaddingScheme::Unpad(const byte *pkcsBlock, size_t pkcsBlockLen, byte *output, const NameValuePairs ¶meters) const
00054 {
00055 bool invalid = false;
00056 size_t maxOutputLen = MaxUnpaddedLength(pkcsBlockLen);
00057
00058
00059 if (pkcsBlockLen % 8 != 0)
00060 {
00061 invalid = (pkcsBlock[0] != 0) || invalid;
00062 pkcsBlock++;
00063 }
00064 pkcsBlockLen /= 8;
00065
00066
00067 invalid = (pkcsBlock[0] != 2) || invalid;
00068
00069
00070 size_t i=1;
00071 while (i<pkcsBlockLen && pkcsBlock[i++]) {
00072 }
00073 assert(i==pkcsBlockLen || pkcsBlock[i-1]==0);
00074
00075 size_t outputLen = pkcsBlockLen - i;
00076 invalid = (outputLen > maxOutputLen) || invalid;
00077
00078 if (invalid)
00079 return DecodingResult();
00080
00081 memcpy (output, pkcsBlock+i, outputLen);
00082 return DecodingResult(outputLen);
00083 }
00084
00085
00086
00087 #ifndef CRYPTOPP_IMPORTS
00088
00089 void PKCS1v15_SignatureMessageEncodingMethod::ComputeMessageRepresentative(RandomNumberGenerator &rng,
00090 const byte *recoverableMessage, size_t recoverableMessageLength,
00091 HashTransformation &hash, HashIdentifier hashIdentifier, bool messageEmpty,
00092 byte *representative, size_t representativeBitLength) const
00093 {
00094 assert(representativeBitLength >= MinRepresentativeBitLength(hashIdentifier.second, hash.DigestSize()));
00095
00096 size_t pkcsBlockLen = representativeBitLength;
00097
00098 if (pkcsBlockLen % 8 != 0)
00099 {
00100 representative[0] = 0;
00101 representative++;
00102 }
00103 pkcsBlockLen /= 8;
00104
00105 representative[0] = 1;
00106
00107 unsigned int digestSize = hash.DigestSize();
00108 byte *pPadding = representative + 1;
00109 byte *pDigest = representative + pkcsBlockLen - digestSize;
00110 byte *pHashId = pDigest - hashIdentifier.second;
00111 byte *pSeparator = pHashId - 1;
00112
00113
00114 memset(pPadding, 0xff, pSeparator-pPadding);
00115 *pSeparator = 0;
00116 memcpy(pHashId, hashIdentifier.first, hashIdentifier.second);
00117 hash.Final(pDigest);
00118 }
00119
00120 #endif
00121
00122 NAMESPACE_END
00123
00124 #endif