diff options
Diffstat (limited to 'crypto/src/math/ec/ECCurve.cs')
| -rw-r--r-- | crypto/src/math/ec/ECCurve.cs | 39 |
1 files changed, 20 insertions, 19 deletions
diff --git a/crypto/src/math/ec/ECCurve.cs b/crypto/src/math/ec/ECCurve.cs index ae0d5d69e..c4a4691d5 100644 --- a/crypto/src/math/ec/ECCurve.cs +++ b/crypto/src/math/ec/ECCurve.cs @@ -110,6 +110,16 @@ namespace Org.BouncyCastle.Math.EC return new Config(this, this.m_coord, this.m_endomorphism, this.m_multiplier); } + public virtual int FieldElementEncodingLength => (FieldSize + 7) / 8; + + public virtual int GetAffinePointEncodingLength(bool compressed) + { + int fieldLength = FieldElementEncodingLength; + return compressed + ? 1 + fieldLength + : 1 + fieldLength * 2; + } + public virtual ECPoint ValidatePoint(BigInteger x, BigInteger y) { ECPoint p = CreatePoint(x, y); @@ -362,24 +372,15 @@ namespace Org.BouncyCastle.Math.EC */ public virtual ECLookupTable CreateCacheSafeLookupTable(ECPoint[] points, int off, int len) { - int FE_BYTES = (FieldSize + 7) / 8; + int FE_BYTES = FieldElementEncodingLength; byte[] table = new byte[len * FE_BYTES * 2]; + int pos = 0; + for (int i = 0; i < len; ++i) { - int pos = 0; - for (int i = 0; i < len; ++i) - { - ECPoint p = points[off + i]; - byte[] px = p.RawXCoord.ToBigInteger().ToByteArray(); - byte[] py = p.RawYCoord.ToBigInteger().ToByteArray(); - - int pxStart = px.Length > FE_BYTES ? 1 : 0, pxLen = px.Length - pxStart; - int pyStart = py.Length > FE_BYTES ? 1 : 0, pyLen = py.Length - pyStart; - - Array.Copy(px, pxStart, table, pos + FE_BYTES - pxLen, pxLen); pos += FE_BYTES; - Array.Copy(py, pyStart, table, pos + FE_BYTES - pyLen, pyLen); pos += FE_BYTES; - } + ECPoint p = points[off + i]; + p.RawXCoord.EncodeTo(table, pos); pos += FE_BYTES; + p.RawYCoord.EncodeTo(table, pos); pos += FE_BYTES; } - return new DefaultLookupTable(this, table, len); } @@ -465,7 +466,7 @@ namespace Org.BouncyCastle.Math.EC return DecodePoint(encoded.AsSpan()); #else ECPoint p; - int expectedLength = (FieldSize + 7) / 8; + int expectedLength = FieldElementEncodingLength; byte type = encoded[0]; switch (type) @@ -538,7 +539,7 @@ namespace Org.BouncyCastle.Math.EC public virtual ECPoint DecodePoint(ReadOnlySpan<byte> encoded) { ECPoint p; - int expectedLength = (FieldSize + 7) / 8; + int expectedLength = FieldElementEncodingLength; byte type = encoded[0]; switch (type) @@ -635,7 +636,7 @@ namespace Org.BouncyCastle.Math.EC public override ECPoint Lookup(int index) { - int FE_BYTES = (m_outer.FieldSize + 7) / 8; + int FE_BYTES = m_outer.FieldElementEncodingLength; byte[] x = new byte[FE_BYTES], y = new byte[FE_BYTES]; int pos = 0; @@ -657,7 +658,7 @@ namespace Org.BouncyCastle.Math.EC public override ECPoint LookupVar(int index) { - int FE_BYTES = (m_outer.FieldSize + 7) / 8; + int FE_BYTES = m_outer.FieldElementEncodingLength; byte[] x = new byte[FE_BYTES], y = new byte[FE_BYTES]; int pos = index * FE_BYTES * 2; |