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jdomnitzjdomnitz
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code cleanup
1 parent e0f0a13 commit b4df0ed

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4 files changed

+33
-146
lines changed

4 files changed

+33
-146
lines changed

‎HomeKitDotNet/Crypto/CryptoBytes.cs‎

Lines changed: 0 additions & 133 deletions
Original file line numberDiff line numberDiff line change
@@ -5,29 +5,6 @@ namespace HomeKitDotNet.Crypto
55
{
66
public static class CryptoBytes
77
{
8-
public static bool ConstantTimeEquals(byte[] x, byte[] y)
9-
{
10-
if (x == null)
11-
throw new ArgumentNullException("x");
12-
if (y == null)
13-
throw new ArgumentNullException("y");
14-
if (x.Length != y.Length)
15-
throw new ArgumentException("x.Length must equal y.Length");
16-
return InternalConstantTimeEquals(x, 0, y, 0, x.Length) != 0;
17-
}
18-
19-
public static bool ConstantTimeEquals(ArraySegment<byte> x, ArraySegment<byte> y)
20-
{
21-
if (x.Array == null)
22-
throw new ArgumentNullException("x.Array");
23-
if (y.Array == null)
24-
throw new ArgumentNullException("y.Array");
25-
if (x.Count != y.Count)
26-
throw new ArgumentException("x.Count must equal y.Count");
27-
28-
return InternalConstantTimeEquals(x.Array, x.Offset, y.Array, y.Offset, x.Count) != 0;
29-
}
30-
318
public static bool ConstantTimeEquals(byte[] x, int xOffset, byte[] y, int yOffset, int length)
329
{
3310
if (x == null)
@@ -63,26 +40,6 @@ public static void Wipe(byte[] data)
6340
InternalWipe(data, 0, data.Length);
6441
}
6542

66-
public static void Wipe(byte[] data, int offset, int count)
67-
{
68-
if (data == null)
69-
throw new ArgumentNullException("data");
70-
if (offset < 0)
71-
throw new ArgumentOutOfRangeException("offset");
72-
if (count < 0)
73-
throw new ArgumentOutOfRangeException("count", "Requires count >= 0");
74-
if ((uint)offset + (uint)count > (uint)data.Length)
75-
throw new ArgumentException("Requires offset + count <= data.Length");
76-
InternalWipe(data, offset, count);
77-
}
78-
79-
public static void Wipe(ArraySegment<byte> data)
80-
{
81-
if (data.Array == null)
82-
throw new ArgumentNullException("data.Array");
83-
InternalWipe(data.Array, data.Offset, data.Count);
84-
}
85-
8643
// Secure wiping is hard
8744
// * the GC can move around and copy memory
8845
// Perhaps this can be avoided by using unmanaged memory or by fixing the position of the array in memory
@@ -96,95 +53,5 @@ internal static void InternalWipe(byte[] data, int offset, int count)
9653
{
9754
Array.Clear(data, offset, count);
9855
}
99-
100-
// shallow wipe of structs
101-
[MethodImpl(MethodImplOptions.NoInlining)]
102-
internal static void InternalWipe<T>(ref T data)
103-
where T : struct
104-
{
105-
data = default;
106-
}
107-
108-
// constant time hex conversion
109-
// see http://stackoverflow.com/a/14333437/445517
110-
//
111-
// An explanation of the weird bit fiddling:
112-
//
113-
// 1. `bytes[i] >> 4` extracts the high nibble of a byte
114-
// `bytes[i] & 0xF` extracts the low nibble of a byte
115-
// 2. `b - 10`
116-
// is `< 0` for values `b < 10`, which will become a decimal digit
117-
// is `>= 0` for values `b > 10`, which will become a letter from `A` to `F`.
118-
// 3. Using `i >> 31` on a signed 32 bit integer extracts the sign, thanks to sign extension.
119-
// It will be `-1` for `i < 0` and `0` for `i >= 0`.
120-
// 4. Combining 2) and 3), shows that `(b-10)>>31` will be `0` for letters and `-1` for digits.
121-
// 5. Looking at the case for letters, the last summand becomes `0`, and `b` is in the range 10 to 15. We want to map it to `A`(65) to `F`(70), which implies adding 55 (`'A'-10`).
122-
// 6. Looking at the case for digits, we want to adapt the last summand so it maps `b` from the range 0 to 9 to the range `0`(48) to `9`(57). This means it needs to become -7 (`'0' - 55`).
123-
// Now we could just multiply with 7. But since -1 is represented by all bits being 1, we can instead use `& -7` since `(0 & -7) == 0` and `(-1 & -7) == -7`.
124-
//
125-
// Some further considerations:
126-
//
127-
// * I didn't use a second loop variable to index into `c`, since measurement shows that calculating it from `i` is cheaper.
128-
// * Using exactly `i < bytes.Length` as upper bound of the loop allows the JITter to eliminate bounds checks on `bytes[i]`, so I chose that variant.
129-
// * Making `b` an int avoids unnecessary conversions from and to byte.
130-
public static string? ToHexStringUpper(byte[] data)
131-
{
132-
if (data == null)
133-
return null;
134-
char[] c = new char[data.Length * 2];
135-
int b;
136-
for (int i = 0; i < data.Length; i++)
137-
{
138-
b = data[i] >> 4;
139-
c[i * 2] = (char)(55 + b + (b - 10 >> 31 & -7));
140-
b = data[i] & 0xF;
141-
c[i * 2 + 1] = (char)(55 + b + (b - 10 >> 31 & -7));
142-
}
143-
return new string(c);
144-
}
145-
146-
// Explanation is similar to ToHexStringUpper
147-
// constant 55 -> 87 and -7 -> -39 to compensate for the offset 32 between lowercase and uppercase letters
148-
public static string? ToHexStringLower(byte[] data)
149-
{
150-
if (data == null)
151-
return null;
152-
char[] c = new char[data.Length * 2];
153-
int b;
154-
for (int i = 0; i < data.Length; i++)
155-
{
156-
b = data[i] >> 4;
157-
c[i * 2] = (char)(87 + b + (b - 10 >> 31 & -39));
158-
b = data[i] & 0xF;
159-
c[i * 2 + 1] = (char)(87 + b + (b - 10 >> 31 & -39));
160-
}
161-
return new string(c);
162-
}
163-
164-
public static byte[]? FromHexString(string hexString)
165-
{
166-
if (hexString == null)
167-
return null;
168-
if (hexString.Length % 2 != 0)
169-
throw new FormatException("The hex string is invalid because it has an odd length");
170-
var result = new byte[hexString.Length / 2];
171-
for (int i = 0; i < result.Length; i++)
172-
result[i] = Convert.ToByte(hexString.Substring(i * 2, 2), 16);
173-
return result;
174-
}
175-
176-
public static string? ToBase64String(byte[] data)
177-
{
178-
if (data == null)
179-
return null;
180-
return Convert.ToBase64String(data);
181-
}
182-
183-
public static byte[]? FromBase64String(string s)
184-
{
185-
if (s == null)
186-
return null;
187-
return Convert.FromBase64String(s);
188-
}
18956
}
19057
}

‎HomeKitDotNet/Crypto/SRP.cs‎

Lines changed: 12 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -1,4 +1,15 @@
1-
using System.Globalization;
1+
// HomeKitDotNet Copyright (C) 2024
2+
//
3+
// This program is free software: you can redistribute it and/or modify
4+
// it under the terms of the GNU Affero General Public License as published by
5+
// the Free Software Foundation, either version 3 of the License, or any later version.
6+
// This program is distributed in the hope that it will be useful,
7+
// but WITHOUT ANY WARRANTY, without even the implied warranty of
8+
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
9+
// See the GNU Affero General Public License for more details.
10+
// You should have received a copy of the GNU Affero General Public License
11+
// along with this program. If not, see <http://www.gnu.org/licenses/>.
12+
213
using System.Numerics;
314
using System.Security.Cryptography;
415
using System.Text;

‎HomeKitDotNet/Crypto/Sha512.cs‎

Lines changed: 0 additions & 12 deletions
Original file line numberDiff line numberDiff line change
@@ -26,13 +26,6 @@ public void Init()
2626
_totalBytes = 0;
2727
}
2828

29-
public void Update(ArraySegment<byte> data)
30-
{
31-
if (data.Array == null)
32-
throw new ArgumentNullException("data.Array");
33-
Update(data.Array, data.Offset, data.Count);
34-
}
35-
3629
public void Update(byte[] data, int offset, int count)
3730
{
3831
if (data == null)
@@ -119,11 +112,6 @@ public byte[] Finish()
119112
return result;
120113
}
121114

122-
public static byte[] Hash(byte[] data)
123-
{
124-
return Hash(data, 0, data.Length);
125-
}
126-
127115
public static byte[] Hash(byte[] data, int offset, int count)
128116
{
129117
var hasher = new Sha512();

‎HomeKitDotNet/TLV/Enums/FeatureFlags.cs‎

Lines changed: 21 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,21 @@
1+
// HomeKitDotNet Copyright (C) 2024
2+
//
3+
// This program is free software: you can redistribute it and/or modify
4+
// it under the terms of the GNU Affero General Public License as published by
5+
// the Free Software Foundation, either version 3 of the License, or any later version.
6+
// This program is distributed in the hope that it will be useful,
7+
// but WITHOUT ANY WARRANTY, without even the implied warranty of
8+
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
9+
// See the GNU Affero General Public License for more details.
10+
// You should have received a copy of the GNU Affero General Public License
11+
// along with this program. If not, see <http://www.gnu.org/licenses/>.
12+
13+
namespace HomeKitDotNet.TLV.Enums
14+
{
15+
public enum FeatureFlags
16+
{
17+
SUPPORTS_APPLE_AUTHENTICATION_COPROCESSOR = 1,
18+
SUPPORTS_SOFTWARE_AUTHENTICATION = 2,
19+
SUPPORTS_UNKNOWN_TV_AUTHENTICATION = 8,
20+
}
21+
}

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