#if !BESTHTTP_DISABLE_ALTERNATE_SSL && (!UNITY_WEBGL || UNITY_EDITOR) #pragma warning disable using System; using System.Diagnostics; using BestHTTP.SecureProtocol.Org.BouncyCastle.Crypto.Parameters; namespace BestHTTP.SecureProtocol.Org.BouncyCastle.Crypto { /** * A wrapper class that allows block ciphers to be used to process data in * a piecemeal fashion. The BufferedBlockCipher outputs a block only when the * buffer is full and more data is being added, or on a doFinal. *
* Note: in the case where the underlying cipher is either a CFB cipher or an * OFB one the last block may not be a multiple of the block size. *
*/ public class BufferedBlockCipher : BufferedCipherBase { internal byte[] buf; internal int bufOff; internal bool forEncryption; internal IBlockCipher cipher; /** * constructor for subclasses */ protected BufferedBlockCipher() { } /** * Create a buffered block cipher without padding. * * @param cipher the underlying block cipher this buffering object wraps. * false otherwise. */ public BufferedBlockCipher( IBlockCipher cipher) { if (cipher == null) throw new ArgumentNullException("cipher"); this.cipher = cipher; buf = new byte[cipher.GetBlockSize()]; bufOff = 0; } public override string AlgorithmName { get { return cipher.AlgorithmName; } } /** * initialise the cipher. * * @param forEncryption if true the cipher is initialised for * encryption, if false for decryption. * @param param the key and other data required by the cipher. * @exception ArgumentException if the parameters argument is * inappropriate. */ // Note: This doubles as the Init in the event that this cipher is being used as an IWrapper public override void Init( bool forEncryption, ICipherParameters parameters) { this.forEncryption = forEncryption; ParametersWithRandom pwr = parameters as ParametersWithRandom; if (pwr != null) parameters = pwr.Parameters; Reset(); cipher.Init(forEncryption, parameters); } /** * return the blocksize for the underlying cipher. * * @return the blocksize for the underlying cipher. */ public override int GetBlockSize() { return cipher.GetBlockSize(); } /** * return the size of the output buffer required for an update * an input of len bytes. * * @param len the length of the input. * @return the space required to accommodate a call to update * with len bytes of input. */ public override int GetUpdateOutputSize( int length) { int total = length + bufOff; int leftOver = total % buf.Length; return total - leftOver; } /** * return the size of the output buffer required for an update plus a * doFinal with an input of len bytes. * * @param len the length of the input. * @return the space required to accommodate a call to update and doFinal * with len bytes of input. */ public override int GetOutputSize( int length) { // Note: Can assume IsPartialBlockOkay is true for purposes of this calculation return length + bufOff; } /** * process a single byte, producing an output block if necessary. * * @param in the input byte. * @param out the space for any output that might be produced. * @param outOff the offset from which the output will be copied. * @return the number of output bytes copied to out. * @exception DataLengthException if there isn't enough space in out. * @exception InvalidOperationException if the cipher isn't initialised. */ public override int ProcessByte( byte input, byte[] output, int outOff) { buf[bufOff++] = input; if (bufOff == buf.Length) { if ((outOff + buf.Length) > output.Length) throw new DataLengthException("output buffer too short"); bufOff = 0; return cipher.ProcessBlock(buf, 0, output, outOff); } return 0; } public override byte[] ProcessByte( byte input) { int outLength = GetUpdateOutputSize(1); byte[] outBytes = outLength > 0 ? new byte[outLength] : null; int pos = ProcessByte(input, outBytes, 0); if (outLength > 0 && pos < outLength) { byte[] tmp = new byte[pos]; Array.Copy(outBytes, 0, tmp, 0, pos); outBytes = tmp; } return outBytes; } public override byte[] ProcessBytes( byte[] input, int inOff, int length) { if (input == null) throw new ArgumentNullException("input"); if (length < 1) return null; int outLength = GetUpdateOutputSize(length); byte[] outBytes = outLength > 0 ? new byte[outLength] : null; int pos = ProcessBytes(input, inOff, length, outBytes, 0); if (outLength > 0 && pos < outLength) { byte[] tmp = new byte[pos]; Array.Copy(outBytes, 0, tmp, 0, pos); outBytes = tmp; } return outBytes; } /** * process an array of bytes, producing output if necessary. * * @param in the input byte array. * @param inOff the offset at which the input data starts. * @param len the number of bytes to be copied out of the input array. * @param out the space for any output that might be produced. * @param outOff the offset from which the output will be copied. * @return the number of output bytes copied to out. * @exception DataLengthException if there isn't enough space in out. * @exception InvalidOperationException if the cipher isn't initialised. */ public override int ProcessBytes( byte[] input, int inOff, int length, byte[] output, int outOff) { if (length < 1) { if (length < 0) throw new ArgumentException("Can't have a negative input length!"); return 0; } int blockSize = GetBlockSize(); int outLength = GetUpdateOutputSize(length); if (outLength > 0) { Check.OutputLength(output, outOff, outLength, "output buffer too short"); } int resultLen = 0; int gapLen = buf.Length - bufOff; if (length > gapLen) { Array.Copy(input, inOff, buf, bufOff, gapLen); resultLen += cipher.ProcessBlock(buf, 0, output, outOff); bufOff = 0; length -= gapLen; inOff += gapLen; while (length > buf.Length) { resultLen += cipher.ProcessBlock(input, inOff, output, outOff + resultLen); length -= blockSize; inOff += blockSize; } } Array.Copy(input, inOff, buf, bufOff, length); bufOff += length; if (bufOff == buf.Length) { resultLen += cipher.ProcessBlock(buf, 0, output, outOff + resultLen); bufOff = 0; } return resultLen; } public override byte[] DoFinal() { byte[] outBytes = EmptyBuffer; int length = GetOutputSize(0); if (length > 0) { outBytes = new byte[length]; int pos = DoFinal(outBytes, 0); if (pos < outBytes.Length) { byte[] tmp = new byte[pos]; Array.Copy(outBytes, 0, tmp, 0, pos); outBytes = tmp; } } else { Reset(); } return outBytes; } public override byte[] DoFinal( byte[] input, int inOff, int inLen) { if (input == null) throw new ArgumentNullException("input"); int length = GetOutputSize(inLen); byte[] outBytes = EmptyBuffer; if (length > 0) { outBytes = new byte[length]; int pos = (inLen > 0) ? ProcessBytes(input, inOff, inLen, outBytes, 0) : 0; pos += DoFinal(outBytes, pos); if (pos < outBytes.Length) { byte[] tmp = new byte[pos]; Array.Copy(outBytes, 0, tmp, 0, pos); outBytes = tmp; } } else { Reset(); } return outBytes; } /** * Process the last block in the buffer. * * @param out the array the block currently being held is copied into. * @param outOff the offset at which the copying starts. * @return the number of output bytes copied to out. * @exception DataLengthException if there is insufficient space in out for * the output, or the input is not block size aligned and should be. * @exception InvalidOperationException if the underlying cipher is not * initialised. * @exception InvalidCipherTextException if padding is expected and not found. * @exception DataLengthException if the input is not block size * aligned. */ public override int DoFinal( byte[] output, int outOff) { try { if (bufOff != 0) { Check.DataLength(!cipher.IsPartialBlockOkay, "data not block size aligned"); Check.OutputLength(output, outOff, bufOff, "output buffer too short for DoFinal()"); // NB: Can't copy directly, or we may write too much output cipher.ProcessBlock(buf, 0, buf, 0); Array.Copy(buf, 0, output, outOff, bufOff); } return bufOff; } finally { Reset(); } } /** * Reset the buffer and cipher. After resetting the object is in the same * state as it was after the last init (if there was one). */ public override void Reset() { Array.Clear(buf, 0, buf.Length); bufOff = 0; cipher.Reset(); } } } #pragma warning restore #endif