You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
302 lines
9.0 KiB
302 lines
9.0 KiB
11 months ago
|
#if !BESTHTTP_DISABLE_ALTERNATE_SSL && (!UNITY_WEBGL || UNITY_EDITOR)
|
||
|
|
#pragma warning disable
|
||
|
|
using System;
|
||
|
|
|
||
|
|
#if UNITY_WSA && !UNITY_EDITOR && !ENABLE_IL2CPP
|
||
|
|
using System.TypeFix;
|
||
|
|
#endif
|
||
|
|
using BestHTTP.SecureProtocol.Org.BouncyCastle.Crypto.Parameters;
|
||
|
|
using BestHTTP.SecureProtocol.Org.BouncyCastle.Utilities;
|
||
|
|
|
||
|
|
namespace BestHTTP.SecureProtocol.Org.BouncyCastle.Crypto.Engines
|
||
|
|
{
|
||
|
|
/**
|
||
|
|
* The specification for RC5 came from the <code>RC5 Encryption Algorithm</code>
|
||
|
|
* publication in RSA CryptoBytes, Spring of 1995.
|
||
|
|
* <em>http://www.rsasecurity.com/rsalabs/cryptobytes</em>.
|
||
|
|
* <p>
|
||
|
|
* This implementation has a word size of 32 bits.</p>
|
||
|
|
*/
|
||
|
|
public class RC532Engine
|
||
|
|
: IBlockCipher
|
||
|
|
{
|
||
|
|
/*
|
||
|
|
* the number of rounds to perform
|
||
|
|
*/
|
||
|
|
private int _noRounds;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* the expanded key array of size 2*(rounds + 1)
|
||
|
|
*/
|
||
|
|
private int [] _S;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* our "magic constants" for 32 32
|
||
|
|
*
|
||
|
|
* Pw = Odd((e-2) * 2^wordsize)
|
||
|
|
* Qw = Odd((o-2) * 2^wordsize)
|
||
|
|
*
|
||
|
|
* where e is the base of natural logarithms (2.718281828...)
|
||
|
|
* and o is the golden ratio (1.61803398...)
|
||
|
|
*/
|
||
|
|
private static readonly int P32 = unchecked((int) 0xb7e15163);
|
||
|
|
private static readonly int Q32 = unchecked((int) 0x9e3779b9);
|
||
|
|
|
||
|
|
private bool forEncryption;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Create an instance of the RC5 encryption algorithm
|
||
|
|
* and set some defaults
|
||
|
|
*/
|
||
|
|
public RC532Engine()
|
||
|
|
{
|
||
|
|
_noRounds = 12; // the default
|
||
|
|
// _S = null;
|
||
|
|
}
|
||
|
|
|
||
|
|
public virtual string AlgorithmName
|
||
|
|
{
|
||
|
|
get { return "RC5-32"; }
|
||
|
|
}
|
||
|
|
|
||
|
|
public virtual bool IsPartialBlockOkay
|
||
|
|
{
|
||
|
|
get { return false; }
|
||
|
|
}
|
||
|
|
|
||
|
|
public virtual int GetBlockSize()
|
||
|
|
{
|
||
|
|
return 2 * 4;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* initialise a RC5-32 cipher.
|
||
|
|
*
|
||
|
|
* @param forEncryption whether or not we are for encryption.
|
||
|
|
* @param parameters the parameters required to set up the cipher.
|
||
|
|
* @exception ArgumentException if the parameters argument is
|
||
|
|
* inappropriate.
|
||
|
|
*/
|
||
|
|
public virtual void Init(
|
||
|
|
bool forEncryption,
|
||
|
|
ICipherParameters parameters)
|
||
|
|
{
|
||
|
|
if (typeof(RC5Parameters).IsInstanceOfType(parameters))
|
||
|
|
{
|
||
|
|
RC5Parameters p = (RC5Parameters)parameters;
|
||
|
|
|
||
|
|
_noRounds = p.Rounds;
|
||
|
|
|
||
|
|
SetKey(p.GetKey());
|
||
|
|
}
|
||
|
|
else if (typeof(KeyParameter).IsInstanceOfType(parameters))
|
||
|
|
{
|
||
|
|
KeyParameter p = (KeyParameter)parameters;
|
||
|
|
|
||
|
|
SetKey(p.GetKey());
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
throw new ArgumentException("invalid parameter passed to RC532 init - " + BestHTTP.SecureProtocol.Org.BouncyCastle.Utilities.Platform.GetTypeName(parameters));
|
||
|
|
}
|
||
|
|
|
||
|
|
this.forEncryption = forEncryption;
|
||
|
|
}
|
||
|
|
|
||
|
|
public virtual int ProcessBlock(
|
||
|
|
byte[] input,
|
||
|
|
int inOff,
|
||
|
|
byte[] output,
|
||
|
|
int outOff)
|
||
|
|
{
|
||
|
|
return (forEncryption)
|
||
|
|
? EncryptBlock(input, inOff, output, outOff)
|
||
|
|
: DecryptBlock(input, inOff, output, outOff);
|
||
|
|
}
|
||
|
|
|
||
|
|
public virtual void Reset()
|
||
|
|
{
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Re-key the cipher.
|
||
|
|
*
|
||
|
|
* @param key the key to be used
|
||
|
|
*/
|
||
|
|
private void SetKey(
|
||
|
|
byte[] key)
|
||
|
|
{
|
||
|
|
//
|
||
|
|
// KEY EXPANSION:
|
||
|
|
//
|
||
|
|
// There are 3 phases to the key expansion.
|
||
|
|
//
|
||
|
|
// Phase 1:
|
||
|
|
// Copy the secret key K[0...b-1] into an array L[0..c-1] of
|
||
|
|
// c = ceil(b/u), where u = 32/8 in little-endian order.
|
||
|
|
// In other words, we fill up L using u consecutive key bytes
|
||
|
|
// of K. Any unfilled byte positions in L are zeroed. In the
|
||
|
|
// case that b = c = 0, set c = 1 and L[0] = 0.
|
||
|
|
//
|
||
|
|
int[] L = new int[(key.Length + (4 - 1)) / 4];
|
||
|
|
|
||
|
|
for (int i = 0; i != key.Length; i++)
|
||
|
|
{
|
||
|
|
L[i / 4] += (key[i] & 0xff) << (8 * (i % 4));
|
||
|
|
}
|
||
|
|
|
||
|
|
//
|
||
|
|
// Phase 2:
|
||
|
|
// Initialize S to a particular fixed pseudo-random bit pattern
|
||
|
|
// using an arithmetic progression modulo 2^wordsize determined
|
||
|
|
// by the magic numbers, Pw & Qw.
|
||
|
|
//
|
||
|
|
_S = new int[2*(_noRounds + 1)];
|
||
|
|
|
||
|
|
_S[0] = P32;
|
||
|
|
for (int i=1; i < _S.Length; i++)
|
||
|
|
{
|
||
|
|
_S[i] = (_S[i-1] + Q32);
|
||
|
|
}
|
||
|
|
|
||
|
|
//
|
||
|
|
// Phase 3:
|
||
|
|
// Mix in the user's secret key in 3 passes over the arrays S & L.
|
||
|
|
// The max of the arrays sizes is used as the loop control
|
||
|
|
//
|
||
|
|
int iter;
|
||
|
|
|
||
|
|
if (L.Length > _S.Length)
|
||
|
|
{
|
||
|
|
iter = 3 * L.Length;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
iter = 3 * _S.Length;
|
||
|
|
}
|
||
|
|
|
||
|
|
int A = 0, B = 0;
|
||
|
|
int ii = 0, jj = 0;
|
||
|
|
|
||
|
|
for (int k = 0; k < iter; k++)
|
||
|
|
{
|
||
|
|
A = _S[ii] = RotateLeft(_S[ii] + A + B, 3);
|
||
|
|
B = L[jj] = RotateLeft( L[jj] + A + B, A+B);
|
||
|
|
ii = (ii+1) % _S.Length;
|
||
|
|
jj = (jj+1) % L.Length;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Encrypt the given block starting at the given offset and place
|
||
|
|
* the result in the provided buffer starting at the given offset.
|
||
|
|
*
|
||
|
|
* @param in in byte buffer containing data to encrypt
|
||
|
|
* @param inOff offset into src buffer
|
||
|
|
* @param out out buffer where encrypted data is written
|
||
|
|
* @param outOff offset into out buffer
|
||
|
|
*/
|
||
|
|
private int EncryptBlock(
|
||
|
|
byte[] input,
|
||
|
|
int inOff,
|
||
|
|
byte[] outBytes,
|
||
|
|
int outOff)
|
||
|
|
{
|
||
|
|
int A = BytesToWord(input, inOff) + _S[0];
|
||
|
|
int B = BytesToWord(input, inOff + 4) + _S[1];
|
||
|
|
|
||
|
|
for (int i = 1; i <= _noRounds; i++)
|
||
|
|
{
|
||
|
|
A = RotateLeft(A ^ B, B) + _S[2*i];
|
||
|
|
B = RotateLeft(B ^ A, A) + _S[2*i+1];
|
||
|
|
}
|
||
|
|
|
||
|
|
WordToBytes(A, outBytes, outOff);
|
||
|
|
WordToBytes(B, outBytes, outOff + 4);
|
||
|
|
|
||
|
|
return 2 * 4;
|
||
|
|
}
|
||
|
|
|
||
|
|
private int DecryptBlock(
|
||
|
|
byte[] input,
|
||
|
|
int inOff,
|
||
|
|
byte[] outBytes,
|
||
|
|
int outOff)
|
||
|
|
{
|
||
|
|
int A = BytesToWord(input, inOff);
|
||
|
|
int B = BytesToWord(input, inOff + 4);
|
||
|
|
|
||
|
|
for (int i = _noRounds; i >= 1; i--)
|
||
|
|
{
|
||
|
|
B = RotateRight(B - _S[2*i+1], A) ^ A;
|
||
|
|
A = RotateRight(A - _S[2*i], B) ^ B;
|
||
|
|
}
|
||
|
|
|
||
|
|
WordToBytes(A - _S[0], outBytes, outOff);
|
||
|
|
WordToBytes(B - _S[1], outBytes, outOff + 4);
|
||
|
|
|
||
|
|
return 2 * 4;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
//////////////////////////////////////////////////////////////
|
||
|
|
//
|
||
|
|
// PRIVATE Helper Methods
|
||
|
|
//
|
||
|
|
//////////////////////////////////////////////////////////////
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Perform a left "spin" of the word. The rotation of the given
|
||
|
|
* word <em>x</em> is rotated left by <em>y</em> bits.
|
||
|
|
* Only the <em>lg(32)</em> low-order bits of <em>y</em>
|
||
|
|
* are used to determine the rotation amount. Here it is
|
||
|
|
* assumed that the wordsize used is a power of 2.
|
||
|
|
*
|
||
|
|
* @param x word to rotate
|
||
|
|
* @param y number of bits to rotate % 32
|
||
|
|
*/
|
||
|
|
private int RotateLeft(int x, int y) {
|
||
|
|
return ((int) ( (uint) (x << (y & (32-1))) |
|
||
|
|
((uint) x >> (32 - (y & (32-1)))) )
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Perform a right "spin" of the word. The rotation of the given
|
||
|
|
* word <em>x</em> is rotated left by <em>y</em> bits.
|
||
|
|
* Only the <em>lg(32)</em> low-order bits of <em>y</em>
|
||
|
|
* are used to determine the rotation amount. Here it is
|
||
|
|
* assumed that the wordsize used is a power of 2.
|
||
|
|
*
|
||
|
|
* @param x word to rotate
|
||
|
|
* @param y number of bits to rotate % 32
|
||
|
|
*/
|
||
|
|
private int RotateRight(int x, int y) {
|
||
|
|
return ((int) ( ((uint) x >> (y & (32-1))) |
|
||
|
|
(uint) (x << (32 - (y & (32-1)))) )
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
private int BytesToWord(
|
||
|
|
byte[] src,
|
||
|
|
int srcOff)
|
||
|
|
{
|
||
|
|
return (src[srcOff] & 0xff) | ((src[srcOff + 1] & 0xff) << 8)
|
||
|
|
| ((src[srcOff + 2] & 0xff) << 16) | ((src[srcOff + 3] & 0xff) << 24);
|
||
|
|
}
|
||
|
|
|
||
|
|
private void WordToBytes(
|
||
|
|
int word,
|
||
|
|
byte[] dst,
|
||
|
|
int dstOff)
|
||
|
|
{
|
||
|
|
dst[dstOff] = (byte)word;
|
||
|
|
dst[dstOff + 1] = (byte)(word >> 8);
|
||
|
|
dst[dstOff + 2] = (byte)(word >> 16);
|
||
|
|
dst[dstOff + 3] = (byte)(word >> 24);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
#pragma warning restore
|
||
|
|
#endif
|