Mercurial > 510Connectbot
annotate src/ch/ethz/ssh2/crypto/cipher/CipherInputStream.java @ 381:95188bd4badb
cleanup help pages
| author | Carl Byington <carl@five-ten-sg.com> |
|---|---|
| date | Wed, 06 Aug 2014 10:38:50 -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 import java.io.IOException; |
|
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
8 import java.io.InputStream; |
|
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
9 |
|
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
10 /** |
|
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
11 * CipherInputStream. |
|
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
12 * |
|
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
13 * @author Christian Plattner |
|
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
14 * @version $Id: CipherInputStream.java 11 2011-05-27 14:14:06Z dkocher@sudo.ch $ |
|
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
15 */ |
| 307 | 16 public class CipherInputStream { |
| 17 BlockCipher currentCipher; | |
| 18 InputStream bi; | |
| 19 byte[] buffer; | |
| 20 byte[] enc; | |
| 21 int blockSize; | |
| 22 int pos; | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
23 |
| 307 | 24 /* |
| 25 * We cannot use java.io.BufferedInputStream, since that is not available in | |
| 26 * J2ME. Everything could be improved alot here. | |
| 27 */ | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
28 |
| 307 | 29 private static final int BUFF_SIZE = 8192; |
| 30 byte[] input_buffer = new byte[BUFF_SIZE]; | |
| 31 int input_buffer_pos = 0; | |
| 32 int input_buffer_size = 0; | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
33 |
| 307 | 34 public CipherInputStream(BlockCipher tc, InputStream bi) { |
| 35 this.bi = bi; | |
| 36 changeCipher(tc); | |
| 37 } | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
38 |
| 307 | 39 private int fill_buffer() throws IOException { |
| 40 input_buffer_pos = 0; | |
| 41 input_buffer_size = 0; | |
| 42 input_buffer_size = bi.read(input_buffer, 0, BUFF_SIZE); | |
| 43 return input_buffer_size; | |
| 44 } | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
45 |
| 307 | 46 private int internal_read(byte[] b, int off, int len) throws IOException { |
| 47 if (input_buffer_size < 0) { | |
| 48 return -1; | |
| 49 } | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
50 |
| 307 | 51 if (input_buffer_pos >= input_buffer_size) { |
| 52 if (fill_buffer() <= 0) { | |
| 53 return -1; | |
| 54 } | |
| 55 } | |
| 56 | |
| 57 int avail = input_buffer_size - input_buffer_pos; | |
| 58 int thiscopy = (len > avail) ? avail : len; | |
| 59 System.arraycopy(input_buffer, input_buffer_pos, b, off, thiscopy); | |
| 60 input_buffer_pos += thiscopy; | |
| 61 return thiscopy; | |
| 62 } | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
63 |
| 307 | 64 public void changeCipher(BlockCipher bc) { |
| 65 this.currentCipher = bc; | |
| 66 blockSize = bc.getBlockSize(); | |
| 67 buffer = new byte[blockSize]; | |
| 68 enc = new byte[blockSize]; | |
| 69 pos = blockSize; | |
| 70 } | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
71 |
| 307 | 72 private void getBlock() throws IOException { |
| 73 int n = 0; | |
| 74 | |
| 75 while (n < blockSize) { | |
| 76 int len = internal_read(enc, n, blockSize - n); | |
| 77 | |
| 78 if (len < 0) { | |
| 79 throw new IOException("Cannot read full block, EOF reached."); | |
| 80 } | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
81 |
| 307 | 82 n += len; |
| 83 } | |
| 84 | |
| 85 try { | |
| 86 currentCipher.transformBlock(enc, 0, buffer, 0); | |
| 87 } | |
| 88 catch (Exception e) { | |
| 89 throw new IOException("Error while decrypting block."); | |
| 90 } | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
91 |
| 307 | 92 pos = 0; |
| 93 } | |
| 94 | |
| 95 public int read(byte[] dst) throws IOException { | |
| 96 return read(dst, 0, dst.length); | |
| 97 } | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
98 |
| 307 | 99 public int read(byte[] dst, int off, int len) throws IOException { |
| 100 int count = 0; | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
101 |
| 307 | 102 while (len > 0) { |
| 103 if (pos >= blockSize) { | |
| 104 getBlock(); | |
| 105 } | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
106 |
| 307 | 107 int avail = blockSize - pos; |
| 108 int copy = Math.min(avail, len); | |
| 109 System.arraycopy(buffer, pos, dst, off, copy); | |
| 110 pos += copy; | |
| 111 off += copy; | |
| 112 len -= copy; | |
| 113 count += copy; | |
| 114 } | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
115 |
| 307 | 116 return count; |
| 117 } | |
| 118 | |
| 119 public int read() throws IOException { | |
| 120 if (pos >= blockSize) { | |
| 121 getBlock(); | |
| 122 } | |
| 123 | |
| 124 return buffer[pos++] & 0xff; | |
| 125 } | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
126 |
| 307 | 127 public int readPlain(byte[] b, int off, int len) throws IOException { |
| 128 if (pos != blockSize) { | |
| 129 throw new IOException("Cannot read plain since crypto buffer is not aligned."); | |
| 130 } | |
| 131 | |
| 132 int n = 0; | |
| 133 | |
| 134 while (n < len) { | |
| 135 int cnt = internal_read(b, off + n, len - n); | |
| 136 | |
| 137 if (cnt < 0) { | |
| 138 throw new IOException("Cannot fill buffer, EOF reached."); | |
| 139 } | |
| 140 | |
| 141 n += cnt; | |
| 142 } | |
| 143 | |
| 144 return n; | |
| 145 } | |
|
273
91a31873c42a
start conversion from trilead to ganymed
Carl Byington <carl@five-ten-sg.com>
parents:
diff
changeset
|
146 } |