| 18 | } |
| 19 | |
| 20 | void OAEP_Base::Pad(RandomNumberGenerator &rng, const byte *input, size_t inputLength, byte *oaepBlock, size_t oaepBlockLen, const NameValuePairs ¶meters) const |
| 21 | { |
| 22 | CRYPTOPP_ASSERT (inputLength <= MaxUnpaddedLength(oaepBlockLen)); |
| 23 | |
| 24 | // convert from bit length to byte length |
| 25 | if (oaepBlockLen % 8 != 0) |
| 26 | { |
| 27 | oaepBlock[0] = 0; |
| 28 | oaepBlock++; |
| 29 | } |
| 30 | oaepBlockLen /= 8; |
| 31 | |
| 32 | member_ptr<HashTransformation> pHash(NewHash()); |
| 33 | const size_t hLen = pHash->DigestSize(); |
| 34 | const size_t seedLen = hLen, dbLen = oaepBlockLen-seedLen; |
| 35 | byte *const maskedSeed = oaepBlock; |
| 36 | byte *const maskedDB = oaepBlock+seedLen; |
| 37 | |
| 38 | ConstByteArrayParameter encodingParameters; |
| 39 | parameters.GetValue(Name::EncodingParameters(), encodingParameters); |
| 40 | |
| 41 | // DB = pHash || 00 ... || 01 || M |
| 42 | pHash->CalculateDigest(maskedDB, encodingParameters.begin(), encodingParameters.size()); |
| 43 | memset(maskedDB+hLen, 0, dbLen-hLen-inputLength-1); |
| 44 | maskedDB[dbLen-inputLength-1] = 0x01; |
| 45 | memcpy(maskedDB+dbLen-inputLength, input, inputLength); |
| 46 | |
| 47 | rng.GenerateBlock(maskedSeed, seedLen); |
| 48 | member_ptr<MaskGeneratingFunction> pMGF(NewMGF()); |
| 49 | pMGF->GenerateAndMask(*pHash, maskedDB, dbLen, maskedSeed, seedLen); |
| 50 | pMGF->GenerateAndMask(*pHash, maskedSeed, seedLen, maskedDB, dbLen); |
| 51 | } |
| 52 | |
| 53 | DecodingResult OAEP_Base::Unpad(const byte *oaepBlock, size_t oaepBlockLen, byte *output, const NameValuePairs ¶meters) const |
| 54 | { |
no test coverage detected