using System; using System.Runtime.CompilerServices; namespace Renci.SshNet.Security.Chaos.NaCl { internal static class CryptoBytes { internal static bool ConstantTimeEquals(byte[] x, byte[] y) { if (x == null) throw new ArgumentNullException("x"); if (y == null) throw new ArgumentNullException("y"); if (x.Length != y.Length) throw new ArgumentException("x.Length must equal y.Length"); return InternalConstantTimeEquals(x, 0, y, 0, x.Length) != 0; } internal static bool ConstantTimeEquals(ArraySegment<byte> x, ArraySegment<byte> y) { if (x.Array == null) throw new ArgumentNullException("x.Array"); if (y.Array == null) throw new ArgumentNullException("y.Array"); if (x.Count != y.Count) throw new ArgumentException("x.Count must equal y.Count"); return InternalConstantTimeEquals(x.Array, x.Offset, y.Array, y.Offset, x.Count) != 0; } internal static bool ConstantTimeEquals(byte[] x, int xOffset, byte[] y, int yOffset, int length) { if (x == null) throw new ArgumentNullException("x"); if (xOffset < 0) throw new ArgumentOutOfRangeException("xOffset", "xOffset < 0"); if (y == null) throw new ArgumentNullException("y"); if (yOffset < 0) throw new ArgumentOutOfRangeException("yOffset", "yOffset < 0"); if (length < 0) throw new ArgumentOutOfRangeException("length", "length < 0"); if (x.Length - xOffset < length) throw new ArgumentException("xOffset + length > x.Length"); if (y.Length - yOffset < length) throw new ArgumentException("yOffset + length > y.Length"); return InternalConstantTimeEquals(x, xOffset, y, yOffset, length) != 0; } private static uint InternalConstantTimeEquals(byte[] x, int xOffset, byte[] y, int yOffset, int length) { int num = 0; for (int i = 0; i < length; i++) { num |= (x[xOffset + i] ^ y[yOffset + i]); } return 1 & ((uint)(num - 1) >> 8); } internal static void Wipe(byte[] data) { if (data == null) throw new ArgumentNullException("data"); InternalWipe(data, 0, data.Length); } internal static void Wipe(byte[] data, int offset, int count) { if (data == null) throw new ArgumentNullException("data"); if (offset < 0) throw new ArgumentOutOfRangeException("offset"); if (count < 0) throw new ArgumentOutOfRangeException("count", "Requires count >= 0"); if ((uint)(offset + count) > (uint)data.Length) throw new ArgumentException("Requires offset + count <= data.Length"); InternalWipe(data, offset, count); } internal static void Wipe(ArraySegment<byte> data) { if (data.Array == null) throw new ArgumentNullException("data.Array"); InternalWipe(data.Array, data.Offset, data.Count); } [MethodImpl(MethodImplOptions.NoInlining)] internal static void InternalWipe(byte[] data, int offset, int count) { Array.Clear(data, offset, count); } [MethodImpl(MethodImplOptions.NoInlining)] internal static void InternalWipe<T>(ref T data) where T : struct { data = default(T); } internal static string ToHexStringUpper(byte[] data) { if (data == null) return null; char[] array = new char[data.Length * 2]; for (int i = 0; i < data.Length; i++) { int num = data[i] >> 4; array[i * 2] = (char)(55 + num + ((num - 10 >> 31) & -7)); num = (data[i] & 15); array[i * 2 + 1] = (char)(55 + num + ((num - 10 >> 31) & -7)); } return new string(array); } internal static string ToHexStringLower(byte[] data) { if (data == null) return null; char[] array = new char[data.Length * 2]; for (int i = 0; i < data.Length; i++) { int num = data[i] >> 4; array[i * 2] = (char)(87 + num + ((num - 10 >> 31) & -39)); num = (data[i] & 15); array[i * 2 + 1] = (char)(87 + num + ((num - 10 >> 31) & -39)); } return new string(array); } internal static byte[] FromHexString(string hexString) { if (hexString == null) return null; if (hexString.Length % 2 != 0) throw new FormatException("The hex string is invalid because it has an odd length"); byte[] array = new byte[hexString.Length / 2]; for (int i = 0; i < array.Length; i++) { array[i] = Convert.ToByte(hexString.Substring(i * 2, 2), 16); } return array; } internal static string ToBase64String(byte[] data) { if (data == null) return null; return Convert.ToBase64String(data); } internal static byte[] FromBase64String(string s) { if (s == null) return null; return Convert.FromBase64String(s); } } }