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1
2 package ch.ethz.ssh2.packets;
3
4 import java.io.IOException  ;
5 import java.math.BigInteger ;
6
7 import ch.ethz.ssh2.util.Tokenizer;
8
9
15 public class TypesReader
16 {
17 byte[] arr;
18 int pos = 0;
19 int max = 0;
20
21 public TypesReader(byte[] arr)
22 {
23 this.arr = arr;
24 pos = 0;
25 max = arr.length;
26 }
27
28 public TypesReader(byte[] arr, int off)
29 {
30 this.arr = arr;
31 this.pos = off;
32 this.max = arr.length;
33
34 if ((pos < 0) || (pos > arr.length))
35 throw new IllegalArgumentException ("Illegal offset.");
36 }
37
38 public TypesReader(byte[] arr, int off, int len)
39 {
40 this.arr = arr;
41 this.pos = off;
42 this.max = off + len;
43
44 if ((pos < 0) || (pos > arr.length))
45 throw new IllegalArgumentException ("Illegal offset.");
46
47 if ((max < 0) || (max > arr.length))
48 throw new IllegalArgumentException ("Illegal length.");
49 }
50
51 public int readByte() throws IOException
52 {
53 if (pos >= max)
54 throw new IOException ("Packet too short.");
55
56 return (arr[pos++] & 0xff);
57 }
58
59 public byte[] readBytes(int len) throws IOException
60 {
61 if ((pos + len) > max)
62 throw new IOException ("Packet too short.");
63
64 byte[] res = new byte[len];
65
66 System.arraycopy(arr, pos, res, 0, len);
67 pos += len;
68
69 return res;
70 }
71
72 public void readBytes(byte[] dst, int off, int len) throws IOException
73 {
74 if ((pos + len) > max)
75 throw new IOException ("Packet too short.");
76
77 System.arraycopy(arr, pos, dst, off, len);
78 pos += len;
79 }
80
81 public boolean readBoolean() throws IOException
82 {
83 if (pos >= max)
84 throw new IOException ("Packet too short.");
85
86 return (arr[pos++] != 0);
87 }
88
89 public int readUINT32() throws IOException
90 {
91 if ((pos + 4) > max)
92 throw new IOException ("Packet too short.");
93
94 return ((arr[pos++] & 0xff) << 24) | ((arr[pos++] & 0xff) << 16) | ((arr[pos++] & 0xff) << 8)
95 | (arr[pos++] & 0xff);
96 }
97
98 public long readUINT64() throws IOException
99 {
100 if ((pos + 8) > max)
101 throw new IOException ("Packet too short.");
102
103 long high = ((arr[pos++] & 0xff) << 24) | ((arr[pos++] & 0xff) << 16) | ((arr[pos++] & 0xff) << 8)
104 | (arr[pos++] & 0xff);
105
106 long low = ((arr[pos++] & 0xff) << 24) | ((arr[pos++] & 0xff) << 16) | ((arr[pos++] & 0xff) << 8)
107 | (arr[pos++] & 0xff);
108
109 return (high << 32) | (low & 0xffffffffl);
110 }
111
112 public BigInteger readMPINT() throws IOException
113 {
114 BigInteger b;
115
116 byte raw[] = readByteString();
117
118 if (raw.length == 0)
119 b = BigInteger.ZERO;
120 else
121 b = new BigInteger (raw);
122
123 return b;
124 }
125
126 public byte[] readByteString() throws IOException
127 {
128 int len = readUINT32();
129
130 if ((len + pos) > max)
131 throw new IOException ("Malformed SSH byte string.");
132
133 byte[] res = new byte[len];
134 System.arraycopy(arr, pos, res, 0, len);
135 pos += len;
136 return res;
137 }
138
139 public String readString(String charsetName) throws IOException
140 {
141 int len = readUINT32();
142
143 if ((len + pos) > max)
144 throw new IOException ("Malformed SSH string.");
145
146 String res = (charsetName == null) ? new String (arr, pos, len) : new String (arr, pos, len, charsetName);
147 pos += len;
148
149 return res;
150 }
151
152 public String readString() throws IOException
153 {
154 int len = readUINT32();
155
156 if ((len + pos) > max)
157 throw new IOException ("Malformed SSH string.");
158
159 String res = new String (arr, pos, len);
160 pos += len;
161
162 return res;
163 }
164
165 public String [] readNameList() throws IOException
166 {
167 return Tokenizer.parseTokens(readString(), ',');
168 }
169
170 public int remain()
171 {
172 return max - pos;
173 }
174
175 }
176 |
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