diff options
Diffstat (limited to 'crypto')
| -rw-r--r-- | crypto/src/math/BigInteger.cs | 93 |
1 files changed, 77 insertions, 16 deletions
diff --git a/crypto/src/math/BigInteger.cs b/crypto/src/math/BigInteger.cs index d6c43cdc0..fc4e15486 100644 --- a/crypto/src/math/BigInteger.cs +++ b/crypto/src/math/BigInteger.cs @@ -538,24 +538,21 @@ namespace Org.BouncyCastle.Math } } - private static int[] MakeMagnitude( - byte[] bytes, - int offset, - int length) + private static int[] MakeMagnitude(byte[] bytes, int offset, int length) { +#if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER + return MakeMagnitude(bytes.AsSpan(offset, length)); +#else int end = offset + length; // strip leading zeros int firstSignificant; - for (firstSignificant = offset; firstSignificant < end - && bytes[firstSignificant] == 0; firstSignificant++) + for (firstSignificant = offset; firstSignificant < end && bytes[firstSignificant] == 0; firstSignificant++) { } if (firstSignificant >= end) - { return ZeroMagnitude; - } int nInts = (end - firstSignificant + 3) / BytesPerInt; int bCount = (end - firstSignificant) % BytesPerInt; @@ -565,10 +562,59 @@ namespace Org.BouncyCastle.Math } if (nInts < 1) + return ZeroMagnitude; + + int[] mag = new int[nInts]; + + int v = 0; + int magnitudeIndex = 0; + for (int i = firstSignificant; i < end; ++i) { + v <<= 8; + v |= bytes[i] & 0xff; + bCount--; + if (bCount <= 0) + { + mag[magnitudeIndex] = v; + magnitudeIndex++; + bCount = BytesPerInt; + v = 0; + } + } + + if (magnitudeIndex < mag.Length) + { + mag[magnitudeIndex] = v; + } + + return mag; +#endif + } + +#if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER + private static int[] MakeMagnitude(ReadOnlySpan<byte> bytes) + { + int end = bytes.Length; + + // strip leading zeros + int firstSignificant; + for (firstSignificant = 0; firstSignificant < end && bytes[firstSignificant] == 0; firstSignificant++) + { + } + + if (firstSignificant >= end) return ZeroMagnitude; + + int nInts = (end - firstSignificant + 3) / BytesPerInt; + int bCount = (end - firstSignificant) % BytesPerInt; + if (bCount == 0) + { + bCount = BytesPerInt; } + if (nInts < 1) + return ZeroMagnitude; + int[] mag = new int[nInts]; int v = 0; @@ -594,19 +640,14 @@ namespace Org.BouncyCastle.Math return mag; } +#endif - public BigInteger( - int sign, - byte[] bytes) + public BigInteger(int sign, byte[] bytes) : this(sign, bytes, 0, bytes.Length) { } - public BigInteger( - int sign, - byte[] bytes, - int offset, - int length) + public BigInteger(int sign, byte[] bytes, int offset, int length) { if (sign < -1 || sign > 1) throw new FormatException("Invalid sign value"); @@ -624,6 +665,26 @@ namespace Org.BouncyCastle.Math } } +#if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER + public BigInteger(int sign, ReadOnlySpan<byte> bytes) + { + if (sign < -1 || sign > 1) + throw new FormatException("Invalid sign value"); + + if (sign == 0) + { + this.sign = 0; + this.magnitude = ZeroMagnitude; + } + else + { + // copy bytes + this.magnitude = MakeMagnitude(bytes); + this.sign = this.magnitude.Length < 1 ? 0 : sign; + } + } +#endif + public BigInteger( int sizeInBits, Random random) |