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1
11 package org.eclipse.team.internal.ccvs.ssh;
12
13 import java.io.FilterInputStream  ;
14 import java.io.IOException ;
15 import java.io.InputStream ;
16
17 class ServerPacket extends Packet {
18 private PacketInputStream pis = null;
19
20 private static class PacketInputStream extends FilterInputStream {
21 private static int MAX_BUFFER_SIZE = 1024;
22
23 private byte[] buffer = new byte[MAX_BUFFER_SIZE];
24 private int bufpos = 0;
25 private int buflen = 0;
26 private int bufrem = 0;
27
28 private long remaining = 0;
29 private Cipher cipher = null;
30
31 private long crc = 0;
32 private boolean closed = false;
33
34 public PacketInputStream(InputStream in, long length, Cipher cipher) {
35 super(in);
36
37 this.remaining = length;
38 this.cipher = cipher;
39 }
40
41 public int available() throws IOException {
42 if (closed) {
43 throw new IOException (CVSSSHMessages.closed);
44 }
45
46 return (int) Math.min(remaining - 4, Integer.MAX_VALUE);
47 }
48
49 public void close() throws IOException {
50 close(true);
51 }
52
53 public void close(boolean doCrcCheck) throws IOException {
54 if (!closed) {
55 try {
56 long toRead = doCrcCheck ? remaining - 4 : remaining;
57
58 try {
59 Misc.skipFully(this, toRead);
60 } catch(IOException e) {
61 }
63
64 if(doCrcCheck) {
65 if ((int) crc != Misc.readInt(buffer, bufpos)) {
66 throw new IOException (CVSSSHMessages.ServerPacket_crc);
67 }
68 }
69 } finally {
70 closed = true;
71 }
72 }
73 }
74
75 private void fill() throws IOException {
76 if (bufrem > 0) {
77 System.arraycopy(buffer, bufpos, buffer, 0, bufrem);
78 }
79
80 int totalBytesRead = bufrem;
81 int read = 0;
82 int toRead = (int)Math.min(remaining - totalBytesRead, MAX_BUFFER_SIZE - totalBytesRead);
83
84 while (toRead > 0) {
85 read = in.read(buffer, totalBytesRead, toRead);
86
87 if (read == -1) {
88 throw new IOException (CVSSSHMessages.stream);
89 }
90
91 totalBytesRead += read;
92 toRead -= read;
93 }
94
95 bufpos = 0;
96
97 buflen = (totalBytesRead / 8) * 8;
98 bufrem = totalBytesRead - buflen;
99
100 if (cipher != null) {
101 cipher.decipher(buffer, 0, buffer, 0, buflen);
102 }
103
104 crc = Misc.crc32(buffer, 0, buflen == remaining ? buflen - 4 : buflen, crc);
105 }
106
107 public int read() throws IOException {
108 if (closed) {
109 throw new IOException (CVSSSHMessages.closed);
110 }
111
112 if (remaining - 4 == 0) {
113 return -1;
114 }
115
116 if (bufpos == buflen) {
117 fill();
118 }
119
120 int b = buffer[bufpos] & 0xff;
121
122 ++bufpos;
123 --remaining;
124
125 return b;
126 }
127
128 public int read(byte b[], int off, int len) throws IOException {
129 if (closed) {
130 throw new IOException (CVSSSHMessages.closed);
131 }
132
133 if (remaining - 4 == 0) {
134 return -1;
135 }
136
137 if (bufpos == buflen) {
138 fill();
139 }
140
141 len = Math.min(len, (buflen == remaining + bufpos ? buflen - 4 : buflen) - bufpos);
142
143 System.arraycopy(buffer, bufpos, b, off, len);
144
145 bufpos += len;
146 remaining -= len;
147
148 return len;
149 }
150 }
151 public ServerPacket(InputStream is, Cipher cipher) throws java.io.IOException {
152 packetLength = Misc.readInt(is);
153 paddingLength = 8 - (packetLength % 8);
154 pis = new PacketInputStream(is, packetLength + paddingLength, cipher);
155 Misc.skipFully(pis, paddingLength);
156 packetType = (byte) pis.read();
157 }
158 public void close(boolean doCrcCheck) throws IOException {
159 pis.close(doCrcCheck);
160 }
161 public InputStream getInputStream() {
162 return pis;
163 }
164 }
165 |
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