diff options
Diffstat (limited to 'src/cz/crcs/ectester/common/util/ECUtil.java')
| -rw-r--r-- | src/cz/crcs/ectester/common/util/ECUtil.java | 19 |
1 files changed, 15 insertions, 4 deletions
diff --git a/src/cz/crcs/ectester/common/util/ECUtil.java b/src/cz/crcs/ectester/common/util/ECUtil.java index 9b0949d..d5e8006 100644 --- a/src/cz/crcs/ectester/common/util/ECUtil.java +++ b/src/cz/crcs/ectester/common/util/ECUtil.java @@ -362,11 +362,22 @@ public class ECUtil { public static BigInteger recoverSignatureNonce(byte[] signature, byte[] data, BigInteger privkey, ECParameterSpec params, String hashType) { try { int bitSize = params.getOrder().bitLength(); - MessageDigest md = MessageDigest.getInstance(hashType); - byte[] hash = md.digest(data); + // Hash the data. + byte[] hash; + if (hashType.equals("NONE")) { + hash = data; + } else { + MessageDigest md = MessageDigest.getInstance(hashType); + hash = md.digest(data); + } + // Trim bitSize of rightmost bits. BigInteger hashInt = new BigInteger(1, hash); - hashInt = hashInt.and(BigInteger.ONE.shiftLeft(bitSize + 1).subtract(BigInteger.ONE)); + int hashBits = hashInt.bitLength(); + if (hashBits > bitSize) { + hashInt = hashInt.shiftRight(hashBits - bitSize); + } + // Parse DERSignature BigInteger[] sigPair = fromDERSignature(signature); BigInteger r = sigPair[0]; BigInteger s = sigPair[1]; @@ -420,7 +431,7 @@ public class ECUtil { FileInputStream in = new FileInputStream(file); result.readCSV(in); in.close(); - } else { + } else if (named != null) { if (params == EC_Consts.PARAMETER_W) { result = EC_Store.getInstance().getObject(EC_Key.Public.class, named); } else if (params == EC_Consts.PARAMETER_S) { |