Mercurial > 510Connectbot
annotate src/ch/ethz/ssh2/crypto/cipher/CBCMode.java @ 326:97da8c5fb40a ganymed
pickup compression from trilead
| author | Carl Byington <carl@five-ten-sg.com> |
|---|---|
| date | Thu, 31 Jul 2014 11:15:15 -0700 |
| parents | 071eccdff8ea |
| children |
| rev | line source |
|---|---|
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
1 /* |
|
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
2 * Copyright (c) 2006-2011 Christian Plattner. All rights reserved. |
|
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
3 * Please refer to the LICENSE.txt for licensing details. |
|
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
4 */ |
|
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
5 package ch.ethz.ssh2.crypto.cipher; |
|
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
6 |
|
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
7 /** |
|
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
8 * CBCMode. |
| 307 | 9 * |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
10 * @author Christian Plattner |
|
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
11 * @version 2.50, 03/15/10 |
|
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
12 */ |
| 307 | 13 public class CBCMode implements BlockCipher { |
| 14 BlockCipher tc; | |
| 15 int blockSize; | |
| 16 boolean doEncrypt; | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
17 |
| 307 | 18 byte[] cbc_vector; |
| 19 byte[] tmp_vector; | |
| 20 | |
| 21 public void init(boolean forEncryption, byte[] key) { | |
| 22 } | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
23 |
| 307 | 24 public CBCMode(BlockCipher tc, byte[] iv, boolean doEncrypt) |
| 25 throws IllegalArgumentException { | |
| 26 this.tc = tc; | |
| 27 this.blockSize = tc.getBlockSize(); | |
| 28 this.doEncrypt = doEncrypt; | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
29 |
| 307 | 30 if (this.blockSize != iv.length) |
| 31 throw new IllegalArgumentException("IV must be " + blockSize | |
| 32 + " bytes long! (currently " + iv.length + ")"); | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
33 |
| 307 | 34 this.cbc_vector = new byte[blockSize]; |
| 35 this.tmp_vector = new byte[blockSize]; | |
| 36 System.arraycopy(iv, 0, cbc_vector, 0, blockSize); | |
| 37 } | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
38 |
| 307 | 39 public int getBlockSize() { |
| 40 return blockSize; | |
| 41 } | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
42 |
| 307 | 43 private void encryptBlock(byte[] src, int srcoff, byte[] dst, int dstoff) { |
| 44 for (int i = 0; i < blockSize; i++) | |
| 45 cbc_vector[i] ^= src[srcoff + i]; | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
46 |
| 307 | 47 tc.transformBlock(cbc_vector, 0, dst, dstoff); |
| 48 System.arraycopy(dst, dstoff, cbc_vector, 0, blockSize); | |
| 49 } | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
50 |
| 307 | 51 private void decryptBlock(byte[] src, int srcoff, byte[] dst, int dstoff) { |
| 52 /* Assume the worst, src and dst are overlapping... */ | |
| 53 System.arraycopy(src, srcoff, tmp_vector, 0, blockSize); | |
| 54 tc.transformBlock(src, srcoff, dst, dstoff); | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
55 |
| 307 | 56 for (int i = 0; i < blockSize; i++) |
| 57 dst[dstoff + i] ^= cbc_vector[i]; | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
58 |
| 307 | 59 /* ...that is why we need a tmp buffer. */ |
| 60 byte[] swap = cbc_vector; | |
| 61 cbc_vector = tmp_vector; | |
| 62 tmp_vector = swap; | |
| 63 } | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
64 |
| 307 | 65 public void transformBlock(byte[] src, int srcoff, byte[] dst, int dstoff) { |
| 66 if (doEncrypt) | |
| 67 encryptBlock(src, srcoff, dst, dstoff); | |
| 68 else | |
| 69 decryptBlock(src, srcoff, dst, dstoff); | |
| 70 } | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
71 } |