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1
17
18 package org.apache.geronimo.util.asn1;
19
20 import java.io.ByteArrayInputStream  ;
21 import java.io.ByteArrayOutputStream ;
22 import java.io.EOFException ;
23 import java.io.FilterInputStream ;
24 import java.io.IOException ;
25 import java.io.InputStream ;
26 import java.util.Vector ;
27
28
34 public class ASN1InputStream
35 extends FilterInputStream
36 implements DERTags
37 {
38 private DERObject END_OF_STREAM = new DERObject() {
39 void encode(
40 DEROutputStream out)
41 throws IOException
42 {
43 throw new IOException ("Eeek!");
44 }
45 public int hashCode()
46 {
47 return 0;
48 }
49 public boolean equals(
50 Object o)
51 {
52 return o == this;
53 }
54 };
55 boolean eofFound = false;
56
57 public ASN1InputStream(
58 InputStream is)
59 {
60 super(is);
61 }
62
63 public ASN1InputStream(
64 byte[] input)
65 {
66 super(new ByteArrayInputStream (input));
67 }
68
69 protected int readLength()
70 throws IOException
71 {
72 int length = read();
73 if (length < 0)
74 {
75 throw new IOException ("EOF found when length expected");
76 }
77
78 if (length == 0x80)
79 {
80 return -1; }
82
83 if (length > 127)
84 {
85 int size = length & 0x7f;
86
87 if (size > 4)
88 {
89 throw new IOException ("DER length more than 4 bytes");
90 }
91
92 length = 0;
93 for (int i = 0; i < size; i++)
94 {
95 int next = read();
96
97 if (next < 0)
98 {
99 throw new IOException ("EOF found reading length");
100 }
101
102 length = (length << 8) + next;
103 }
104
105 if (length < 0)
106 {
107 throw new IOException ("corrupted steam - negative length found");
108 }
109 }
110
111 return length;
112 }
113
114 protected void readFully(
115 byte[] bytes)
116 throws IOException
117 {
118 int left = bytes.length;
119 int len;
120
121 if (left == 0)
122 {
123 return;
124 }
125
126 while ((len = read(bytes, bytes.length - left, left)) > 0)
127 {
128 if ((left -= len) == 0)
129 {
130 return;
131 }
132 }
133
134 if (left != 0)
135 {
136 throw new EOFException ("EOF encountered in middle of object");
137 }
138 }
139
140
144 protected DERObject buildObject(
145 int tag,
146 byte[] bytes)
147 throws IOException
148 {
149 if ((tag & APPLICATION) != 0)
150 {
151 return new DERApplicationSpecific(tag, bytes);
152 }
153
154 switch (tag)
155 {
156 case NULL:
157 return new DERNull();
158 case SEQUENCE | CONSTRUCTED:
159 ByteArrayInputStream bIn = new ByteArrayInputStream (bytes);
160 ASN1InputStream aIn = new ASN1InputStream(bIn);
161 ASN1EncodableVector v = new ASN1EncodableVector();
162
163 DERObject obj = aIn.readObject();
164
165 while (obj != null)
166 {
167 v.add(obj);
168 obj = aIn.readObject();
169 }
170
171 return new DERSequence(v);
172 case SET | CONSTRUCTED:
173 bIn = new ByteArrayInputStream (bytes);
174 aIn = new ASN1InputStream(bIn);
175 v = new ASN1EncodableVector();
176
177 obj = aIn.readObject();
178
179 while (obj != null)
180 {
181 v.add(obj);
182 obj = aIn.readObject();
183 }
184
185 return new DERSet(v, false);
186 case BOOLEAN:
187 return new DERBoolean(bytes);
188 case INTEGER:
189 return new DERInteger(bytes);
190 case ENUMERATED:
191 return new DEREnumerated(bytes);
192 case OBJECT_IDENTIFIER:
193 return new DERObjectIdentifier(bytes);
194 case BIT_STRING:
195 int padBits = bytes[0];
196 byte[] data = new byte[bytes.length - 1];
197
198 System.arraycopy(bytes, 1, data, 0, bytes.length - 1);
199
200 return new DERBitString(data, padBits);
201 case NUMERIC_STRING:
202 return new DERNumericString(bytes);
203 case UTF8_STRING:
204 return new DERUTF8String(bytes);
205 case PRINTABLE_STRING:
206 return new DERPrintableString(bytes);
207 case IA5_STRING:
208 return new DERIA5String(bytes);
209 case T61_STRING:
210 return new DERT61String(bytes);
211 case VISIBLE_STRING:
212 return new DERVisibleString(bytes);
213 case GENERAL_STRING:
214 return new DERGeneralString(bytes);
215 case UNIVERSAL_STRING:
216 return new DERUniversalString(bytes);
217 case BMP_STRING:
218 return new DERBMPString(bytes);
219 case OCTET_STRING:
220 return new DEROctetString(bytes);
221 case UTC_TIME:
222 return new DERUTCTime(bytes);
223 case GENERALIZED_TIME:
224 return new DERGeneralizedTime(bytes);
225 default:
226 if ((tag & TAGGED) != 0)
230 {
231 int tagNo = tag & 0x1f;
232
233 if (tagNo == 0x1f)
234 {
235 int idx = 0;
236
237 tagNo = 0;
238
239 while ((bytes[idx] & 0x80) != 0)
240 {
241 tagNo |= (bytes[idx++] & 0x7f);
242 tagNo <<= 7;
243 }
244
245 tagNo |= (bytes[idx] & 0x7f);
246
247 byte[] tmp = bytes;
248
249 bytes = new byte[tmp.length - (idx + 1)];
250 System.arraycopy(tmp, idx + 1, bytes, 0, bytes.length);
251 }
252
253 if (bytes.length == 0) {
255 if ((tag & CONSTRUCTED) == 0)
256 {
257 return new DERTaggedObject(false, tagNo, new DERNull());
258 }
259 else
260 {
261 return new DERTaggedObject(false, tagNo, new DERSequence());
262 }
263 }
264
265 if ((tag & CONSTRUCTED) == 0)
269 {
270 return new DERTaggedObject(false, tagNo, new DEROctetString(bytes));
271 }
272
273 bIn = new ByteArrayInputStream (bytes);
274 aIn = new ASN1InputStream(bIn);
275
276 DEREncodable dObj = aIn.readObject();
277
278 if (aIn.available() == 0)
283 {
284 return new DERTaggedObject(tagNo, dObj);
285 }
286
287 v = new ASN1EncodableVector();
291
292 while (dObj != null)
293 {
294 v.add(dObj);
295 dObj = aIn.readObject();
296 }
297
298 return new DERTaggedObject(false, tagNo, new DERSequence(v));
299 }
300
301 return new DERUnknownTag(tag, bytes);
302 }
303 }
304
305
308 private byte[] readIndefiniteLengthFully()
309 throws IOException
310 {
311 ByteArrayOutputStream bOut = new ByteArrayOutputStream ();
312 int b, b1;
313
314 b1 = read();
315
316 while ((b = read()) >= 0)
317 {
318 if (b1 == 0 && b == 0)
319 {
320 break;
321 }
322
323 bOut.write(b1);
324 b1 = b;
325 }
326
327 return bOut.toByteArray();
328 }
329
330 private BERConstructedOctetString buildConstructedOctetString()
331 throws IOException
332 {
333 Vector octs = new Vector ();
334
335 for (;;)
336 {
337 DERObject o = readObject();
338
339 if (o == END_OF_STREAM)
340 {
341 break;
342 }
343
344 octs.addElement(o);
345 }
346
347 return new BERConstructedOctetString(octs);
348 }
349
350 public DERObject readObject()
351 throws IOException
352 {
353 int tag = read();
354 if (tag == -1)
355 {
356 if (eofFound)
357 {
358 throw new EOFException ("attempt to read past end of file.");
359 }
360
361 eofFound = true;
362
363 return null;
364 }
365
366 int length = readLength();
367
368 if (length < 0) {
370 switch (tag)
371 {
372 case NULL:
373 return new BERNull();
374 case SEQUENCE | CONSTRUCTED:
375 ASN1EncodableVector v = new ASN1EncodableVector();
376
377 for (;;)
378 {
379 DERObject obj = readObject();
380
381 if (obj == END_OF_STREAM)
382 {
383 break;
384 }
385
386 v.add(obj);
387 }
388 return new BERSequence(v);
389 case SET | CONSTRUCTED:
390 v = new ASN1EncodableVector();
391
392 for (;;)
393 {
394 DERObject obj = readObject();
395
396 if (obj == END_OF_STREAM)
397 {
398 break;
399 }
400
401 v.add(obj);
402 }
403 return new BERSet(v, false);
404 case OCTET_STRING | CONSTRUCTED:
405 return buildConstructedOctetString();
406 default:
407 if ((tag & TAGGED) != 0)
411 {
412 int tagNo = tag & 0x1f;
413
414 if (tagNo == 0x1f)
415 {
416 int b = read();
417
418 tagNo = 0;
419
420 while ((b >= 0) && ((b & 0x80) != 0))
421 {
422 tagNo |= (b & 0x7f);
423 tagNo <<= 7;
424 b = read();
425 }
426
427 tagNo |= (b & 0x7f);
428 }
429
430 if ((tag & CONSTRUCTED) == 0)
434 {
435 byte[] bytes = readIndefiniteLengthFully();
436
437 return new BERTaggedObject(false, tagNo, new DEROctetString(bytes));
438 }
439
440 DERObject dObj = readObject();
444
445 if (dObj == END_OF_STREAM) {
447 return new DERTaggedObject(tagNo);
448 }
449
450 DERObject next = readObject();
451
452 if (next == END_OF_STREAM)
457 {
458 return new BERTaggedObject(tagNo, dObj);
459 }
460
461 v = new ASN1EncodableVector();
465
466 v.add(dObj);
467
468 do
469 {
470 v.add(next);
471 next = readObject();
472 }
473 while (next != END_OF_STREAM);
474
475 return new BERTaggedObject(false, tagNo, new BERSequence(v));
476 }
477
478 throw new IOException ("unknown BER object encountered");
479 }
480 }
481 else
482 {
483 if (tag == 0 && length == 0) {
485 return END_OF_STREAM;
486 }
487
488 byte[] bytes = new byte[length];
489
490 readFully(bytes);
491
492 return buildObject(tag, bytes);
493 }
494 }
495 }
496 |
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