Unity_Web/Assets/Best HTTP/Source/SecureProtocol/crypto/engines/Grain128AEADEngine.cs

569 lines
18 KiB
C#

#if !BESTHTTP_DISABLE_ALTERNATE_SSL && (!UNITY_WEBGL || UNITY_EDITOR)
#pragma warning disable
using System;
using System.IO;
using BestHTTP.SecureProtocol.Org.BouncyCastle.Crypto.Modes;
using BestHTTP.SecureProtocol.Org.BouncyCastle.Crypto.Parameters;
using BestHTTP.SecureProtocol.Org.BouncyCastle.Crypto.Utilities;
namespace BestHTTP.SecureProtocol.Org.BouncyCastle.Crypto.Engines
{
public sealed class Grain128AeadEngine
: IAeadCipher
{
/**
* Constants
*/
private static readonly int STATE_SIZE = 4;
/**
* Variables to hold the state of the engine during encryption and
* decryption
*/
private byte[] workingKey;
private byte[] workingIV;
private uint[] lfsr;
private uint[] nfsr;
private uint[] authAcc;
private uint[] authSr;
private bool initialised = false;
private bool aadFinished = false;
private MemoryStream aadData = new MemoryStream();
private byte[] mac;
public string AlgorithmName => "Grain-128AEAD";
/**
* Initialize a Grain-128AEAD cipher.
*
* @param forEncryption Whether or not we are for encryption.
* @param param The parameters required to set up the cipher.
* @throws ArgumentException If the params argument is inappropriate.
*/
public void Init(bool forEncryption, ICipherParameters param)
{
/*
* Grain encryption and decryption is completely symmetrical, so the
* 'forEncryption' is irrelevant.
*/
if (!(param is ParametersWithIV ivParams))
throw new ArgumentException("Grain-128AEAD Init parameters must include an IV");
byte[] iv = ivParams.GetIV();
if (iv == null || iv.Length != 12)
throw new ArgumentException("Grain-128AEAD requires exactly 12 bytes of IV");
if (!(ivParams.Parameters is KeyParameter key))
throw new ArgumentException("Grain-128AEAD Init parameters must include a key");
byte[] keyBytes = key.GetKey();
if (keyBytes.Length != 16)
throw new ArgumentException("Grain-128AEAD key must be 128 bits long");
/*
* Initialize variables.
*/
workingIV = new byte[keyBytes.Length];
workingKey = keyBytes;
lfsr = new uint[STATE_SIZE];
nfsr = new uint[STATE_SIZE];
authAcc = new uint[2];
authSr = new uint[2];
Array.Copy(iv, 0, workingIV, 0, iv.Length);
Reset();
}
/**
* 320 clocks initialization phase.
*/
private void InitGrain()
{
for (int i = 0; i < 320; ++i)
{
uint outputZ = GetOutput();
nfsr = Shift(nfsr, (GetOutputNFSR() ^ lfsr[0] ^ outputZ) & 1);
lfsr = Shift(lfsr, (GetOutputLFSR() ^ outputZ) & 1);
}
for (int quotient = 0; quotient < 8; ++quotient)
{
for (int remainder = 0; remainder < 8; ++remainder)
{
uint outputZ = GetOutput();
nfsr = Shift(nfsr, (GetOutputNFSR() ^ lfsr[0] ^ outputZ ^ (uint)((workingKey[quotient]) >> remainder)) & 1);
lfsr = Shift(lfsr, (GetOutputLFSR() ^ outputZ ^ (uint)((workingKey[quotient + 8]) >> remainder)) & 1);
}
}
for (int quotient = 0; quotient < 2; ++quotient)
{
for (int remainder = 0; remainder < 32; ++remainder)
{
uint outputZ = GetOutput();
nfsr = Shift(nfsr, (GetOutputNFSR() ^ lfsr[0]) & 1);
lfsr = Shift(lfsr, (GetOutputLFSR()) & 1);
authAcc[quotient] |= outputZ << remainder;
}
}
for (int quotient = 0; quotient < 2; ++quotient)
{
for (int remainder = 0; remainder < 32; ++remainder)
{
uint outputZ = GetOutput();
nfsr = Shift(nfsr, (GetOutputNFSR() ^ lfsr[0]) & 1);
lfsr = Shift(lfsr, (GetOutputLFSR()) & 1);
authSr[quotient] |= outputZ << remainder;
}
}
initialised = true;
}
/**
* Get output from non-linear function g(x).
*
* @return Output from NFSR.
*/
private uint GetOutputNFSR()
{
uint b0 = nfsr[0];
uint b3 = nfsr[0] >> 3;
uint b11 = nfsr[0] >> 11;
uint b13 = nfsr[0] >> 13;
uint b17 = nfsr[0] >> 17;
uint b18 = nfsr[0] >> 18;
uint b22 = nfsr[0] >> 22;
uint b24 = nfsr[0] >> 24;
uint b25 = nfsr[0] >> 25;
uint b26 = nfsr[0] >> 26;
uint b27 = nfsr[0] >> 27;
uint b40 = nfsr[1] >> 8;
uint b48 = nfsr[1] >> 16;
uint b56 = nfsr[1] >> 24;
uint b59 = nfsr[1] >> 27;
uint b61 = nfsr[1] >> 29;
uint b65 = nfsr[2] >> 1;
uint b67 = nfsr[2] >> 3;
uint b68 = nfsr[2] >> 4;
uint b70 = nfsr[2] >> 6;
uint b78 = nfsr[2] >> 14;
uint b82 = nfsr[2] >> 18;
uint b84 = nfsr[2] >> 20;
uint b88 = nfsr[2] >> 24;
uint b91 = nfsr[2] >> 27;
uint b92 = nfsr[2] >> 28;
uint b93 = nfsr[2] >> 29;
uint b95 = nfsr[2] >> 31;
uint b96 = nfsr[3];
return (b0 ^ b26 ^ b56 ^ b91 ^ b96 ^ b3 & b67 ^ b11 & b13 ^ b17 & b18
^ b27 & b59 ^ b40 & b48 ^ b61 & b65 ^ b68 & b84 ^ b22 & b24 & b25 ^ b70 & b78 & b82 ^ b88 & b92 & b93 & b95) & 1;
}
/**
* Get output from linear function f(x).
*
* @return Output from LFSR.
*/
private uint GetOutputLFSR()
{
uint s0 = lfsr[0];
uint s7 = lfsr[0] >> 7;
uint s38 = lfsr[1] >> 6;
uint s70 = lfsr[2] >> 6;
uint s81 = lfsr[2] >> 17;
uint s96 = lfsr[3];
return (s0 ^ s7 ^ s38 ^ s70 ^ s81 ^ s96) & 1;
}
/**
* Get output from output function h(x).
*
* @return y_t.
*/
private uint GetOutput()
{
uint b2 = nfsr[0] >> 2;
uint b12 = nfsr[0] >> 12;
uint b15 = nfsr[0] >> 15;
uint b36 = nfsr[1] >> 4;
uint b45 = nfsr[1] >> 13;
uint b64 = nfsr[2];
uint b73 = nfsr[2] >> 9;
uint b89 = nfsr[2] >> 25;
uint b95 = nfsr[2] >> 31;
uint s8 = lfsr[0] >> 8;
uint s13 = lfsr[0] >> 13;
uint s20 = lfsr[0] >> 20;
uint s42 = lfsr[1] >> 10;
uint s60 = lfsr[1] >> 28;
uint s79 = lfsr[2] >> 15;
uint s93 = lfsr[2] >> 29;
uint s94 = lfsr[2] >> 30;
return ((b12 & s8) ^ (s13 & s20) ^ (b95 & s42) ^ (s60 & s79) ^ (b12 & b95 & s94) ^ s93
^ b2 ^ b15 ^ b36 ^ b45 ^ b64 ^ b73 ^ b89) & 1;
}
/**
* Shift array 1 bit and add val to index.Length - 1.
*
* @param array The array to shift.
* @param val The value to shift in.
* @return The shifted array with val added to index.Length - 1.
*/
private uint[] Shift(uint[] array, uint val)
{
array[0] = (array[0] >> 1) | (array[1] << 31);
array[1] = (array[1] >> 1) | (array[2] << 31);
array[2] = (array[2] >> 1) | (array[3] << 31);
array[3] = (array[3] >> 1) | (val << 31);
return array;
}
/**
* Set keys, reset cipher.
*
* @param keyBytes The key.
* @param ivBytes The IV.
*/
private void SetKey(byte[] keyBytes, byte[] ivBytes)
{
ivBytes[12] = 0xFF;
ivBytes[13] = 0xFF;
ivBytes[14] = 0xFF;
ivBytes[15] = 0x7F;
workingKey = keyBytes;
workingIV = ivBytes;
/*
* Load NFSR and LFSR
*/
Pack.LE_To_UInt32(workingKey, 0, nfsr);
Pack.LE_To_UInt32(workingIV, 0, lfsr);
}
public int ProcessBytes(byte[] input, int inOff, int len, byte[] output, int outOff)
{
Check.DataLength(input, inOff, len, "input buffer too short");
Check.OutputLength(output, outOff, len, "output buffer too short");
#if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || _UNITY_2021_2_OR_NEWER_
return ProcessBytes(input.AsSpan(inOff, len), output.AsSpan(outOff));
#else
if (!initialised)
throw new ArgumentException(AlgorithmName + " not initialised");
if (!aadFinished)
{
DoProcessAADBytes(aadData.GetBuffer(), 0, (int)aadData.Length);
aadFinished = true;
}
GetKeyStream(input, inOff, len, output, outOff);
return len;
#endif
}
#if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || _UNITY_2021_2_OR_NEWER_
public int ProcessBytes(ReadOnlySpan<byte> input, Span<byte> output)
{
Check.OutputLength(output, input.Length, "output buffer too short");
if (!initialised)
throw new ArgumentException(AlgorithmName + " not initialised");
if (!aadFinished)
{
DoProcessAADBytes(aadData.GetBuffer(), 0, (int)aadData.Length);
aadFinished = true;
}
GetKeyStream(input, output);
return input.Length;
}
#endif
public void Reset()
{
Reset(true);
}
private void Reset(bool clearMac)
{
if (clearMac)
{
this.mac = null;
}
this.aadData.SetLength(0);
this.aadFinished = false;
SetKey(workingKey, workingIV);
InitGrain();
}
#if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || _UNITY_2021_2_OR_NEWER_
private void GetKeyStream(ReadOnlySpan<byte> input, Span<byte> output)
{
int len = input.Length;
for (int i = 0; i < len; ++i)
{
uint cc = 0, input_i = input[i];
for (int j = 0; j < 8; ++j)
{
uint outputZ = GetOutput();
nfsr = Shift(nfsr, (GetOutputNFSR() ^ lfsr[0]) & 1);
lfsr = Shift(lfsr, (GetOutputLFSR()) & 1);
uint input_i_j = (input_i >> j) & 1U;
cc |= (input_i_j ^ outputZ) << j;
//if (input_i_j != 0)
//{
// Accumulate();
//}
uint mask = 0U - input_i_j;
authAcc[0] ^= authSr[0] & mask;
authAcc[1] ^= authSr[1] & mask;
AuthShift(GetOutput());
nfsr = Shift(nfsr, (GetOutputNFSR() ^ lfsr[0]) & 1);
lfsr = Shift(lfsr, (GetOutputLFSR()) & 1);
}
output[i] = (byte)cc;
}
}
#else
private void GetKeyStream(byte[] input, int inOff, int len, byte[] ciphertext, int outOff)
{
for (int i = 0; i < len; ++i)
{
uint cc = 0, input_i = input[inOff + i];
for (int j = 0; j < 8; ++j)
{
uint outputZ = GetOutput();
nfsr = Shift(nfsr, (GetOutputNFSR() ^ lfsr[0]) & 1);
lfsr = Shift(lfsr, (GetOutputLFSR()) & 1);
uint input_i_j = (input_i >> j) & 1U;
cc |= (input_i_j ^ outputZ) << j;
//if (input_i_j != 0)
//{
// Accumulate();
//}
uint mask = 0U - input_i_j;
authAcc[0] ^= authSr[0] & mask;
authAcc[1] ^= authSr[1] & mask;
AuthShift(GetOutput());
nfsr = Shift(nfsr, (GetOutputNFSR() ^ lfsr[0]) & 1);
lfsr = Shift(lfsr, (GetOutputLFSR()) & 1);
}
ciphertext[outOff + i] = (byte)cc;
}
}
#endif
public byte ReturnByte(byte input)
{
if (!initialised)
throw new ArgumentException(AlgorithmName + " not initialised");
#if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || _UNITY_2021_2_OR_NEWER_
Span<byte> plaintext = stackalloc byte[1]{ input };
Span<byte> ciphertext = stackalloc byte[1];
GetKeyStream(plaintext, ciphertext);
return ciphertext[0];
#else
byte[] plaintext = new byte[1]{ input };
byte[] ciphertext = new byte[1];
GetKeyStream(plaintext, 0, 1, ciphertext, 0);
return ciphertext[0];
#endif
}
public void ProcessAadByte(byte input)
{
if (aadFinished)
throw new ArgumentException("associated data must be added before plaintext/ciphertext");
aadData.WriteByte(input);
}
public void ProcessAadBytes(byte[] input, int inOff, int len)
{
if (aadFinished)
throw new ArgumentException("associated data must be added before plaintext/ciphertext");
aadData.Write(input, inOff, len);
}
#if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || _UNITY_2021_2_OR_NEWER_
public void ProcessAadBytes(ReadOnlySpan<byte> input)
{
if (aadFinished)
throw new ArgumentException("associated data must be added before plaintext/ciphertext");
aadData.Write(input);
}
#endif
private void Accumulate()
{
authAcc[0] ^= authSr[0];
authAcc[1] ^= authSr[1];
}
private void AuthShift(uint val)
{
authSr[0] = (authSr[0] >> 1) | (authSr[1] << 31);
authSr[1] = (authSr[1] >> 1) | (val << 31);
}
public int ProcessByte(byte input, byte[] output, int outOff)
{
return ProcessBytes(new byte[]{ input }, 0, 1, output, outOff);
}
#if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || _UNITY_2021_2_OR_NEWER_
public int ProcessByte(byte input, Span<byte> output)
{
return ProcessBytes(stackalloc byte[1]{ input }, output);
}
#endif
private void DoProcessAADBytes(byte[] input, int inOff, int len)
{
byte[] ader;
int aderlen;
//encodeDer
if (len < 128)
{
ader = new byte[1 + len];
ader[0] = (byte)len;
aderlen = 0;
}
else
{
// aderlen is the highest bit position divided by 8
aderlen = LenLength(len);
ader = new byte[aderlen + 1 + len];
ader[0] = (byte)(0x80 | (uint)aderlen);
uint tmp = (uint)len;
for (int i = 0; i < aderlen; ++i)
{
ader[1 + i] = (byte)tmp;
tmp >>= 8;
}
}
for (int i = 0; i < len; ++i)
{
ader[1 + aderlen + i] = input[inOff + i];
}
for (int i = 0; i < ader.Length; ++i)
{
uint ader_i = ader[i];
for (int j = 0; j < 8; ++j)
{
nfsr = Shift(nfsr, (GetOutputNFSR() ^ lfsr[0]) & 1);
lfsr = Shift(lfsr, (GetOutputLFSR()) & 1);
uint ader_i_j = (ader_i >> j) & 1U;
//if (ader_i_j != 0)
//{
// Accumulate();
//}
uint mask = 0U - ader_i_j;
authAcc[0] ^= authSr[0] & mask;
authAcc[1] ^= authSr[1] & mask;
AuthShift(GetOutput());
nfsr = Shift(nfsr, (GetOutputNFSR() ^ lfsr[0]) & 1);
lfsr = Shift(lfsr, (GetOutputLFSR()) & 1);
}
}
}
public int DoFinal(byte[] output, int outOff)
{
#if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || _UNITY_2021_2_OR_NEWER_
return DoFinal(output.AsSpan(outOff));
#else
if (!aadFinished)
{
DoProcessAADBytes(aadData.GetBuffer(), 0, (int)aadData.Length);
aadFinished = true;
}
Accumulate();
this.mac = Pack.UInt32_To_LE(authAcc);
Array.Copy(mac, 0, output, outOff, mac.Length);
Reset(false);
return mac.Length;
#endif
}
#if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || _UNITY_2021_2_OR_NEWER_
public int DoFinal(Span<byte> output)
{
if (!aadFinished)
{
DoProcessAADBytes(aadData.GetBuffer(), 0, (int)aadData.Length);
aadFinished = true;
}
Accumulate();
this.mac = Pack.UInt32_To_LE(authAcc);
mac.CopyTo(output);
Reset(false);
return mac.Length;
}
#endif
public byte[] GetMac()
{
return mac;
}
public int GetUpdateOutputSize(int len)
{
return len;
}
public int GetOutputSize(int len)
{
return len + 8;
}
private static int LenLength(int v)
{
if ((v & 0xff) == v)
return 1;
if ((v & 0xffff) == v)
return 2;
if ((v & 0xffffff) == v)
return 3;
return 4;
}
}
}
#pragma warning restore
#endif