diff options
| -rw-r--r-- | crypto/src/math/ec/ECCurve.cs | 26 |
1 files changed, 20 insertions, 6 deletions
diff --git a/crypto/src/math/ec/ECCurve.cs b/crypto/src/math/ec/ECCurve.cs index 50ff88e82..9c16375e6 100644 --- a/crypto/src/math/ec/ECCurve.cs +++ b/crypto/src/math/ec/ECCurve.cs @@ -362,23 +362,37 @@ namespace Org.BouncyCastle.Math.EC throw new ArgumentException("Incorrect length for compressed encoding", "encoded"); int yTilde = encoded[0] & 1; - BigInteger X1 = new BigInteger(1, encoded, 1, expectedLength); + BigInteger X = new BigInteger(1, encoded, 1, expectedLength); - p = DecompressPoint(yTilde, X1); + p = DecompressPoint(yTilde, X); break; } case 0x04: // uncompressed + { + if (encoded.Length != (2 * expectedLength + 1)) + throw new ArgumentException("Incorrect length for uncompressed encoding", "encoded"); + + BigInteger X = new BigInteger(1, encoded, 1, expectedLength); + BigInteger Y = new BigInteger(1, encoded, 1 + expectedLength, expectedLength); + + p = CreatePoint(X, Y); + break; + } + case 0x06: // hybrid case 0x07: // hybrid { if (encoded.Length != (2 * expectedLength + 1)) - throw new ArgumentException("Incorrect length for uncompressed/hybrid encoding", "encoded"); + throw new ArgumentException("Incorrect length for hybrid encoding", "encoded"); + + BigInteger X = new BigInteger(1, encoded, 1, expectedLength); + BigInteger Y = new BigInteger(1, encoded, 1 + expectedLength, expectedLength); - BigInteger X1 = new BigInteger(1, encoded, 1, expectedLength); - BigInteger Y1 = new BigInteger(1, encoded, 1 + expectedLength, expectedLength); + if (Y.TestBit(0) != (encoded[0] == 0x07)) + throw new ArgumentException("Inconsistent Y coordinate in hybrid encoding", "encoded"); - p = CreatePoint(X1, Y1); + p = CreatePoint(X, Y); break; } |