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1
17
18 package org.apache.geronimo.util.asn1;
19
20 import java.io.ByteArrayInputStream  ;
21 import java.io.EOFException ;
22 import java.io.FilterInputStream ;
23 import java.io.IOException ;
24 import java.io.InputStream ;
25
26
32 public class DERInputStream
33 extends FilterInputStream implements DERTags
34 {
35
38 public DERInputStream(
39 InputStream is)
40 {
41 super(is);
42 }
43
44 protected int readLength()
45 throws IOException
46 {
47 int length = read();
48 if (length < 0)
49 {
50 throw new IOException ("EOF found when length expected");
51 }
52
53 if (length == 0x80)
54 {
55 return -1; }
57
58 if (length > 127)
59 {
60 int size = length & 0x7f;
61
62 if (size > 4)
63 {
64 throw new IOException ("DER length more than 4 bytes");
65 }
66
67 length = 0;
68 for (int i = 0; i < size; i++)
69 {
70 int next = read();
71
72 if (next < 0)
73 {
74 throw new IOException ("EOF found reading length");
75 }
76
77 length = (length << 8) + next;
78 }
79
80 if (length < 0)
81 {
82 throw new IOException ("corrupted steam - negative length found");
83 }
84 }
85
86 return length;
87 }
88
89 protected void readFully(
90 byte[] bytes)
91 throws IOException
92 {
93 int left = bytes.length;
94
95 if (left == 0)
96 {
97 return;
98 }
99
100 while (left > 0)
101 {
102 int l = read(bytes, bytes.length - left, left);
103
104 if (l < 0)
105 {
106 throw new EOFException ("unexpected end of stream");
107 }
108
109 left -= l;
110 }
111 }
112
113
117 protected DERObject buildObject(
118 int tag,
119 byte[] bytes)
120 throws IOException
121 {
122 switch (tag)
123 {
124 case NULL:
125 return null;
126 case SEQUENCE | CONSTRUCTED:
127 ByteArrayInputStream bIn = new ByteArrayInputStream (bytes);
128 BERInputStream dIn = new BERInputStream(bIn);
129 DERConstructedSequence seq = new DERConstructedSequence();
130
131 try
132 {
133 for (;;)
134 {
135 DERObject obj = dIn.readObject();
136
137 seq.addObject(obj);
138 }
139 }
140 catch (EOFException ex)
141 {
142 return seq;
143 }
144 case SET | CONSTRUCTED:
145 bIn = new ByteArrayInputStream (bytes);
146 dIn = new BERInputStream(bIn);
147
148 ASN1EncodableVector v = new ASN1EncodableVector();
149
150 try
151 {
152 for (;;)
153 {
154 DERObject obj = dIn.readObject();
155
156 v.add(obj);
157 }
158 }
159 catch (EOFException ex)
160 {
161 return new DERConstructedSet(v);
162 }
163 case BOOLEAN:
164 return new DERBoolean(bytes);
165 case INTEGER:
166 return new DERInteger(bytes);
167 case ENUMERATED:
168 return new DEREnumerated(bytes);
169 case OBJECT_IDENTIFIER:
170 return new DERObjectIdentifier(bytes);
171 case BIT_STRING:
172 int padBits = bytes[0];
173 byte[] data = new byte[bytes.length - 1];
174
175 System.arraycopy(bytes, 1, data, 0, bytes.length - 1);
176
177 return new DERBitString(data, padBits);
178 case UTF8_STRING:
179 return new DERUTF8String(bytes);
180 case PRINTABLE_STRING:
181 return new DERPrintableString(bytes);
182 case IA5_STRING:
183 return new DERIA5String(bytes);
184 case T61_STRING:
185 return new DERT61String(bytes);
186 case VISIBLE_STRING:
187 return new DERVisibleString(bytes);
188 case UNIVERSAL_STRING:
189 return new DERUniversalString(bytes);
190 case GENERAL_STRING:
191 return new DERGeneralString(bytes);
192 case BMP_STRING:
193 return new DERBMPString(bytes);
194 case OCTET_STRING:
195 return new DEROctetString(bytes);
196 case UTC_TIME:
197 return new DERUTCTime(bytes);
198 case GENERALIZED_TIME:
199 return new DERGeneralizedTime(bytes);
200 default:
201 if ((tag & TAGGED) != 0)
205 {
206 if ((tag & 0x1f) == 0x1f)
207 {
208 throw new IOException ("unsupported high tag encountered");
209 }
210
211 if (bytes.length == 0) {
213 if ((tag & CONSTRUCTED) == 0)
214 {
215 return new DERTaggedObject(false, tag & 0x1f, new DERNull());
216 }
217 else
218 {
219 return new DERTaggedObject(false, tag & 0x1f, new DERConstructedSequence());
220 }
221 }
222
223 if ((tag & CONSTRUCTED) == 0)
227 {
228 return new DERTaggedObject(false, tag & 0x1f, new DEROctetString(bytes));
229 }
230
231 bIn = new ByteArrayInputStream (bytes);
232 dIn = new BERInputStream(bIn);
233
234 DEREncodable dObj = dIn.readObject();
235
236 if (dIn.available() == 0)
241 {
242 return new DERTaggedObject(tag & 0x1f, dObj);
243 }
244
245 seq = new DERConstructedSequence();
249
250 seq.addObject(dObj);
251
252 try
253 {
254 for (;;)
255 {
256 dObj = dIn.readObject();
257
258 seq.addObject(dObj);
259 }
260 }
261 catch (EOFException ex)
262 {
263 }
265
266 return new DERTaggedObject(false, tag & 0x1f, seq);
267 }
268
269 return new DERUnknownTag(tag, bytes);
270 }
271 }
272
273 public DERObject readObject()
274 throws IOException
275 {
276 int tag = read();
277 if (tag == -1)
278 {
279 throw new EOFException ();
280 }
281
282 int length = readLength();
283 byte[] bytes = new byte[length];
284
285 readFully(bytes);
286
287 return buildObject(tag, bytes);
288 }
289 }
290 |
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