diff --git a/crypto/src/math/ec/ECCurve.cs b/crypto/src/math/ec/ECCurve.cs
index 38e05991e..905ddb247 100644
--- a/crypto/src/math/ec/ECCurve.cs
+++ b/crypto/src/math/ec/ECCurve.cs
@@ -436,67 +436,143 @@ namespace Org.BouncyCastle.Math.EC
*/
public virtual ECPoint DecodePoint(byte[] encoded)
{
- ECPoint p = null;
+#if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER
+ return DecodePoint(encoded.AsSpan());
+#else
+ ECPoint p;
int expectedLength = (FieldSize + 7) / 8;
byte type = encoded[0];
switch (type)
{
- case 0x00: // infinity
- {
- if (encoded.Length != 1)
- throw new ArgumentException("Incorrect length for infinity encoding", "encoded");
+ case 0x00: // infinity
+ {
+ if (encoded.Length != 1)
+ throw new ArgumentException("Incorrect length for infinity encoding", "encoded");
- p = Infinity;
- break;
- }
+ p = Infinity;
+ break;
+ }
- case 0x02: // compressed
- case 0x03: // compressed
- {
- if (encoded.Length != (expectedLength + 1))
- throw new ArgumentException("Incorrect length for compressed encoding", "encoded");
+ case 0x02: // compressed
+ case 0x03: // compressed
+ {
+ if (encoded.Length != (expectedLength + 1))
+ throw new ArgumentException("Incorrect length for compressed encoding", "encoded");
- int yTilde = type & 1;
- BigInteger X = new BigInteger(1, encoded, 1, expectedLength);
+ int yTilde = type & 1;
+ BigInteger X = new BigInteger(1, encoded, 1, expectedLength);
- p = DecompressPoint(yTilde, X);
- if (!p.ImplIsValid(true, true))
- throw new ArgumentException("Invalid point");
+ p = DecompressPoint(yTilde, X);
+ if (!p.ImplIsValid(true, true))
+ throw new ArgumentException("Invalid point");
- break;
- }
+ break;
+ }
- case 0x04: // uncompressed
- {
- if (encoded.Length != (2 * expectedLength + 1))
- throw new ArgumentException("Incorrect length for uncompressed encoding", "encoded");
+ 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);
+ BigInteger X = new BigInteger(1, encoded, 1, expectedLength);
+ BigInteger Y = new BigInteger(1, encoded, 1 + expectedLength, expectedLength);
- p = ValidatePoint(X, Y);
- break;
- }
+ p = ValidatePoint(X, Y);
+ break;
+ }
- case 0x06: // hybrid
- case 0x07: // hybrid
- {
- if (encoded.Length != (2 * expectedLength + 1))
- throw new ArgumentException("Incorrect length for hybrid encoding", "encoded");
+ case 0x06: // hybrid
+ case 0x07: // hybrid
+ {
+ if (encoded.Length != (2 * expectedLength + 1))
+ 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 X = new BigInteger(1, encoded, 1, expectedLength);
+ BigInteger Y = new BigInteger(1, encoded, 1 + expectedLength, expectedLength);
- if (Y.TestBit(0) != (type == 0x07))
- throw new ArgumentException("Inconsistent Y coordinate in hybrid encoding", "encoded");
+ if (Y.TestBit(0) != (type == 0x07))
+ throw new ArgumentException("Inconsistent Y coordinate in hybrid encoding", "encoded");
- p = ValidatePoint(X, Y);
- break;
- }
+ p = ValidatePoint(X, Y);
+ break;
+ }
- default:
- throw new FormatException("Invalid point encoding " + type);
+ default:
+ throw new FormatException("Invalid point encoding " + type);
+ }
+
+ if (type != 0x00 && p.IsInfinity)
+ throw new ArgumentException("Invalid infinity encoding", "encoded");
+
+ return p;
+#endif
+ }
+
+#if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER
+ public virtual ECPoint DecodePoint(ReadOnlySpan<byte> encodedX)
+ {
+ ECPoint p;
+ int expectedLength = (FieldSize + 7) / 8;
+
+ byte type = encodedX[0];
+ switch (type)
+ {
+ case 0x00: // infinity
+ {
+ if (encodedX.Length != 1)
+ throw new ArgumentException("Incorrect length for infinity encoding", "encoded");
+
+ p = Infinity;
+ break;
+ }
+
+ case 0x02: // compressed
+ case 0x03: // compressed
+ {
+ if (encodedX.Length != (expectedLength + 1))
+ throw new ArgumentException("Incorrect length for compressed encoding", "encoded");
+
+ int yTilde = type & 1;
+ BigInteger X = new BigInteger(1, encodedX[1..]);
+
+ p = DecompressPoint(yTilde, X);
+ if (!p.ImplIsValid(true, true))
+ throw new ArgumentException("Invalid point");
+
+ break;
+ }
+
+ case 0x04: // uncompressed
+ {
+ if (encodedX.Length != (2 * expectedLength + 1))
+ throw new ArgumentException("Incorrect length for uncompressed encoding", "encoded");
+
+ BigInteger X = new BigInteger(1, encodedX[1..(1 + expectedLength)]);
+ BigInteger Y = new BigInteger(1, encodedX[(1 + expectedLength)..]);
+
+ p = ValidatePoint(X, Y);
+ break;
+ }
+
+ case 0x06: // hybrid
+ case 0x07: // hybrid
+ {
+ if (encodedX.Length != (2 * expectedLength + 1))
+ throw new ArgumentException("Incorrect length for hybrid encoding", "encoded");
+
+ BigInteger X = new BigInteger(1, encodedX[1..(1 + expectedLength)]);
+ BigInteger Y = new BigInteger(1, encodedX[(1 + expectedLength)..]);
+
+ if (Y.TestBit(0) != (type == 0x07))
+ throw new ArgumentException("Inconsistent Y coordinate in hybrid encoding", "encoded");
+
+ p = ValidatePoint(X, Y);
+ break;
+ }
+
+ default:
+ throw new FormatException("Invalid point encoding " + type);
}
if (type != 0x00 && p.IsInfinity)
@@ -504,6 +580,7 @@ namespace Org.BouncyCastle.Math.EC
return p;
}
+#endif
private class DefaultLookupTable
: AbstractECLookupTable
|
