Shuyi Chen | d7955ce | 2013-05-22 14:51:55 -0700 | [diff] [blame] | 1 | // Copyright (c) 1999-2004 Brian Wellington (bwelling@xbill.org) |
| 2 | |
| 3 | package org.xbill.DNS; |
| 4 | |
| 5 | import java.io.*; |
| 6 | import java.util.*; |
| 7 | |
| 8 | /** |
| 9 | * A DNS Zone. This encapsulates all data related to a Zone, and provides |
| 10 | * convenient lookup methods. |
| 11 | * |
| 12 | * @author Brian Wellington |
| 13 | */ |
| 14 | |
| 15 | public class Zone implements Serializable { |
| 16 | |
| 17 | private static final long serialVersionUID = -9220510891189510942L; |
| 18 | |
| 19 | /** A primary zone */ |
| 20 | public static final int PRIMARY = 1; |
| 21 | |
| 22 | /** A secondary zone */ |
| 23 | public static final int SECONDARY = 2; |
| 24 | |
| 25 | private Map data; |
| 26 | private Name origin; |
| 27 | private Object originNode; |
| 28 | private int dclass = DClass.IN; |
| 29 | private RRset NS; |
| 30 | private SOARecord SOA; |
| 31 | private boolean hasWild; |
| 32 | |
| 33 | class ZoneIterator implements Iterator { |
| 34 | private Iterator zentries; |
| 35 | private RRset [] current; |
| 36 | private int count; |
| 37 | private boolean wantLastSOA; |
| 38 | |
| 39 | ZoneIterator(boolean axfr) { |
| 40 | synchronized (Zone.this) { |
| 41 | zentries = data.entrySet().iterator(); |
| 42 | } |
| 43 | wantLastSOA = axfr; |
| 44 | RRset [] sets = allRRsets(originNode); |
| 45 | current = new RRset[sets.length]; |
| 46 | for (int i = 0, j = 2; i < sets.length; i++) { |
| 47 | int type = sets[i].getType(); |
| 48 | if (type == Type.SOA) |
| 49 | current[0] = sets[i]; |
| 50 | else if (type == Type.NS) |
| 51 | current[1] = sets[i]; |
| 52 | else |
| 53 | current[j++] = sets[i]; |
| 54 | } |
| 55 | } |
| 56 | |
| 57 | public boolean |
| 58 | hasNext() { |
| 59 | return (current != null || wantLastSOA); |
| 60 | } |
| 61 | |
| 62 | public Object |
| 63 | next() { |
| 64 | if (!hasNext()) { |
| 65 | throw new NoSuchElementException(); |
| 66 | } |
| 67 | if (current == null) { |
| 68 | wantLastSOA = false; |
| 69 | return oneRRset(originNode, Type.SOA); |
| 70 | } |
| 71 | Object set = current[count++]; |
| 72 | if (count == current.length) { |
| 73 | current = null; |
| 74 | while (zentries.hasNext()) { |
| 75 | Map.Entry entry = (Map.Entry) zentries.next(); |
| 76 | if (entry.getKey().equals(origin)) |
| 77 | continue; |
| 78 | RRset [] sets = allRRsets(entry.getValue()); |
| 79 | if (sets.length == 0) |
| 80 | continue; |
| 81 | current = sets; |
| 82 | count = 0; |
| 83 | break; |
| 84 | } |
| 85 | } |
| 86 | return set; |
| 87 | } |
| 88 | |
| 89 | public void |
| 90 | remove() { |
| 91 | throw new UnsupportedOperationException(); |
| 92 | } |
| 93 | } |
| 94 | |
| 95 | private void |
| 96 | validate() throws IOException { |
| 97 | originNode = exactName(origin); |
| 98 | if (originNode == null) |
| 99 | throw new IOException(origin + ": no data specified"); |
| 100 | |
| 101 | RRset rrset = oneRRset(originNode, Type.SOA); |
| 102 | if (rrset == null || rrset.size() != 1) |
| 103 | throw new IOException(origin + |
| 104 | ": exactly 1 SOA must be specified"); |
| 105 | Iterator it = rrset.rrs(); |
| 106 | SOA = (SOARecord) it.next(); |
| 107 | |
| 108 | NS = oneRRset(originNode, Type.NS); |
| 109 | if (NS == null) |
| 110 | throw new IOException(origin + ": no NS set specified"); |
| 111 | } |
| 112 | |
| 113 | private final void |
| 114 | maybeAddRecord(Record record) throws IOException { |
| 115 | int rtype = record.getType(); |
| 116 | Name name = record.getName(); |
| 117 | |
| 118 | if (rtype == Type.SOA && !name.equals(origin)) { |
| 119 | throw new IOException("SOA owner " + name + |
| 120 | " does not match zone origin " + |
| 121 | origin); |
| 122 | } |
| 123 | if (name.subdomain(origin)) |
| 124 | addRecord(record); |
| 125 | } |
| 126 | |
| 127 | /** |
| 128 | * Creates a Zone from the records in the specified master file. |
| 129 | * @param zone The name of the zone. |
| 130 | * @param file The master file to read from. |
| 131 | * @see Master |
| 132 | */ |
| 133 | public |
| 134 | Zone(Name zone, String file) throws IOException { |
| 135 | data = new TreeMap(); |
| 136 | |
| 137 | if (zone == null) |
| 138 | throw new IllegalArgumentException("no zone name specified"); |
| 139 | Master m = new Master(file, zone); |
| 140 | Record record; |
| 141 | |
| 142 | origin = zone; |
| 143 | while ((record = m.nextRecord()) != null) |
| 144 | maybeAddRecord(record); |
| 145 | validate(); |
| 146 | } |
| 147 | |
| 148 | /** |
| 149 | * Creates a Zone from an array of records. |
| 150 | * @param zone The name of the zone. |
| 151 | * @param records The records to add to the zone. |
| 152 | * @see Master |
| 153 | */ |
| 154 | public |
| 155 | Zone(Name zone, Record [] records) throws IOException { |
| 156 | data = new TreeMap(); |
| 157 | |
| 158 | if (zone == null) |
| 159 | throw new IllegalArgumentException("no zone name specified"); |
| 160 | origin = zone; |
| 161 | for (int i = 0; i < records.length; i++) |
| 162 | maybeAddRecord(records[i]); |
| 163 | validate(); |
| 164 | } |
| 165 | |
| 166 | private void |
| 167 | fromXFR(ZoneTransferIn xfrin) throws IOException, ZoneTransferException { |
| 168 | data = new TreeMap(); |
| 169 | |
| 170 | origin = xfrin.getName(); |
| 171 | List records = xfrin.run(); |
| 172 | for (Iterator it = records.iterator(); it.hasNext(); ) { |
| 173 | Record record = (Record) it.next(); |
| 174 | maybeAddRecord(record); |
| 175 | } |
| 176 | if (!xfrin.isAXFR()) |
| 177 | throw new IllegalArgumentException("zones can only be " + |
| 178 | "created from AXFRs"); |
| 179 | validate(); |
| 180 | } |
| 181 | |
| 182 | /** |
| 183 | * Creates a Zone by doing the specified zone transfer. |
| 184 | * @param xfrin The incoming zone transfer to execute. |
| 185 | * @see ZoneTransferIn |
| 186 | */ |
| 187 | public |
| 188 | Zone(ZoneTransferIn xfrin) throws IOException, ZoneTransferException { |
| 189 | fromXFR(xfrin); |
| 190 | } |
| 191 | |
| 192 | /** |
| 193 | * Creates a Zone by performing a zone transfer to the specified host. |
| 194 | * @see ZoneTransferIn |
| 195 | */ |
| 196 | public |
| 197 | Zone(Name zone, int dclass, String remote) |
| 198 | throws IOException, ZoneTransferException |
| 199 | { |
| 200 | ZoneTransferIn xfrin = ZoneTransferIn.newAXFR(zone, remote, null); |
| 201 | xfrin.setDClass(dclass); |
| 202 | fromXFR(xfrin); |
| 203 | } |
| 204 | |
| 205 | /** Returns the Zone's origin */ |
| 206 | public Name |
| 207 | getOrigin() { |
| 208 | return origin; |
| 209 | } |
| 210 | |
| 211 | /** Returns the Zone origin's NS records */ |
| 212 | public RRset |
| 213 | getNS() { |
| 214 | return NS; |
| 215 | } |
| 216 | |
| 217 | /** Returns the Zone's SOA record */ |
| 218 | public SOARecord |
| 219 | getSOA() { |
| 220 | return SOA; |
| 221 | } |
| 222 | |
| 223 | /** Returns the Zone's class */ |
| 224 | public int |
| 225 | getDClass() { |
| 226 | return dclass; |
| 227 | } |
| 228 | |
| 229 | private synchronized Object |
| 230 | exactName(Name name) { |
| 231 | return data.get(name); |
| 232 | } |
| 233 | |
| 234 | private synchronized RRset [] |
| 235 | allRRsets(Object types) { |
| 236 | if (types instanceof List) { |
| 237 | List typelist = (List) types; |
| 238 | return (RRset []) typelist.toArray(new RRset[typelist.size()]); |
| 239 | } else { |
| 240 | RRset set = (RRset) types; |
| 241 | return new RRset [] {set}; |
| 242 | } |
| 243 | } |
| 244 | |
| 245 | private synchronized RRset |
| 246 | oneRRset(Object types, int type) { |
| 247 | if (type == Type.ANY) |
| 248 | throw new IllegalArgumentException("oneRRset(ANY)"); |
| 249 | if (types instanceof List) { |
| 250 | List list = (List) types; |
| 251 | for (int i = 0; i < list.size(); i++) { |
| 252 | RRset set = (RRset) list.get(i); |
| 253 | if (set.getType() == type) |
| 254 | return set; |
| 255 | } |
| 256 | } else { |
| 257 | RRset set = (RRset) types; |
| 258 | if (set.getType() == type) |
| 259 | return set; |
| 260 | } |
| 261 | return null; |
| 262 | } |
| 263 | |
| 264 | private synchronized RRset |
| 265 | findRRset(Name name, int type) { |
| 266 | Object types = exactName(name); |
| 267 | if (types == null) |
| 268 | return null; |
| 269 | return oneRRset(types, type); |
| 270 | } |
| 271 | |
| 272 | private synchronized void |
| 273 | addRRset(Name name, RRset rrset) { |
| 274 | if (!hasWild && name.isWild()) |
| 275 | hasWild = true; |
| 276 | Object types = data.get(name); |
| 277 | if (types == null) { |
| 278 | data.put(name, rrset); |
| 279 | return; |
| 280 | } |
| 281 | int rtype = rrset.getType(); |
| 282 | if (types instanceof List) { |
| 283 | List list = (List) types; |
| 284 | for (int i = 0; i < list.size(); i++) { |
| 285 | RRset set = (RRset) list.get(i); |
| 286 | if (set.getType() == rtype) { |
| 287 | list.set(i, rrset); |
| 288 | return; |
| 289 | } |
| 290 | } |
| 291 | list.add(rrset); |
| 292 | } else { |
| 293 | RRset set = (RRset) types; |
| 294 | if (set.getType() == rtype) |
| 295 | data.put(name, rrset); |
| 296 | else { |
| 297 | LinkedList list = new LinkedList(); |
| 298 | list.add(set); |
| 299 | list.add(rrset); |
| 300 | data.put(name, list); |
| 301 | } |
| 302 | } |
| 303 | } |
| 304 | |
| 305 | private synchronized void |
| 306 | removeRRset(Name name, int type) { |
| 307 | Object types = data.get(name); |
| 308 | if (types == null) { |
| 309 | return; |
| 310 | } |
| 311 | if (types instanceof List) { |
| 312 | List list = (List) types; |
| 313 | for (int i = 0; i < list.size(); i++) { |
| 314 | RRset set = (RRset) list.get(i); |
| 315 | if (set.getType() == type) { |
| 316 | list.remove(i); |
| 317 | if (list.size() == 0) |
| 318 | data.remove(name); |
| 319 | return; |
| 320 | } |
| 321 | } |
| 322 | } else { |
| 323 | RRset set = (RRset) types; |
| 324 | if (set.getType() != type) |
| 325 | return; |
| 326 | data.remove(name); |
| 327 | } |
| 328 | } |
| 329 | |
| 330 | private synchronized SetResponse |
| 331 | lookup(Name name, int type) { |
| 332 | int labels; |
| 333 | int olabels; |
| 334 | int tlabels; |
| 335 | RRset rrset; |
| 336 | Name tname; |
| 337 | Object types; |
| 338 | SetResponse sr; |
| 339 | |
| 340 | if (!name.subdomain(origin)) |
| 341 | return SetResponse.ofType(SetResponse.NXDOMAIN); |
| 342 | |
| 343 | labels = name.labels(); |
| 344 | olabels = origin.labels(); |
| 345 | |
| 346 | for (tlabels = olabels; tlabels <= labels; tlabels++) { |
| 347 | boolean isOrigin = (tlabels == olabels); |
| 348 | boolean isExact = (tlabels == labels); |
| 349 | |
| 350 | if (isOrigin) |
| 351 | tname = origin; |
| 352 | else if (isExact) |
| 353 | tname = name; |
| 354 | else |
| 355 | tname = new Name(name, labels - tlabels); |
| 356 | |
| 357 | types = exactName(tname); |
| 358 | if (types == null) |
| 359 | continue; |
| 360 | |
| 361 | /* If this is a delegation, return that. */ |
| 362 | if (!isOrigin) { |
| 363 | RRset ns = oneRRset(types, Type.NS); |
| 364 | if (ns != null) |
| 365 | return new SetResponse(SetResponse.DELEGATION, |
| 366 | ns); |
| 367 | } |
| 368 | |
| 369 | /* If this is an ANY lookup, return everything. */ |
| 370 | if (isExact && type == Type.ANY) { |
| 371 | sr = new SetResponse(SetResponse.SUCCESSFUL); |
| 372 | RRset [] sets = allRRsets(types); |
| 373 | for (int i = 0; i < sets.length; i++) |
| 374 | sr.addRRset(sets[i]); |
| 375 | return sr; |
| 376 | } |
| 377 | |
| 378 | /* |
| 379 | * If this is the name, look for the actual type or a CNAME. |
| 380 | * Otherwise, look for a DNAME. |
| 381 | */ |
| 382 | if (isExact) { |
| 383 | rrset = oneRRset(types, type); |
| 384 | if (rrset != null) { |
| 385 | sr = new SetResponse(SetResponse.SUCCESSFUL); |
| 386 | sr.addRRset(rrset); |
| 387 | return sr; |
| 388 | } |
| 389 | rrset = oneRRset(types, Type.CNAME); |
| 390 | if (rrset != null) |
| 391 | return new SetResponse(SetResponse.CNAME, |
| 392 | rrset); |
| 393 | } else { |
| 394 | rrset = oneRRset(types, Type.DNAME); |
| 395 | if (rrset != null) |
| 396 | return new SetResponse(SetResponse.DNAME, |
| 397 | rrset); |
| 398 | } |
| 399 | |
| 400 | /* We found the name, but not the type. */ |
| 401 | if (isExact) |
| 402 | return SetResponse.ofType(SetResponse.NXRRSET); |
| 403 | } |
| 404 | |
| 405 | if (hasWild) { |
| 406 | for (int i = 0; i < labels - olabels; i++) { |
| 407 | tname = name.wild(i + 1); |
| 408 | |
| 409 | types = exactName(tname); |
| 410 | if (types == null) |
| 411 | continue; |
| 412 | |
| 413 | rrset = oneRRset(types, type); |
| 414 | if (rrset != null) { |
| 415 | sr = new SetResponse(SetResponse.SUCCESSFUL); |
| 416 | sr.addRRset(rrset); |
| 417 | return sr; |
| 418 | } |
| 419 | } |
| 420 | } |
| 421 | |
| 422 | return SetResponse.ofType(SetResponse.NXDOMAIN); |
| 423 | } |
| 424 | |
| 425 | /** |
| 426 | * Looks up Records in the Zone. This follows CNAMEs and wildcards. |
| 427 | * @param name The name to look up |
| 428 | * @param type The type to look up |
| 429 | * @return A SetResponse object |
| 430 | * @see SetResponse |
| 431 | */ |
| 432 | public SetResponse |
| 433 | findRecords(Name name, int type) { |
| 434 | return lookup(name, type); |
| 435 | } |
| 436 | |
| 437 | /** |
| 438 | * Looks up Records in the zone, finding exact matches only. |
| 439 | * @param name The name to look up |
| 440 | * @param type The type to look up |
| 441 | * @return The matching RRset |
| 442 | * @see RRset |
| 443 | */ |
| 444 | public RRset |
| 445 | findExactMatch(Name name, int type) { |
| 446 | Object types = exactName(name); |
| 447 | if (types == null) |
| 448 | return null; |
| 449 | return oneRRset(types, type); |
| 450 | } |
| 451 | |
| 452 | /** |
| 453 | * Adds an RRset to the Zone |
| 454 | * @param rrset The RRset to be added |
| 455 | * @see RRset |
| 456 | */ |
| 457 | public void |
| 458 | addRRset(RRset rrset) { |
| 459 | Name name = rrset.getName(); |
| 460 | addRRset(name, rrset); |
| 461 | } |
| 462 | |
| 463 | /** |
| 464 | * Adds a Record to the Zone |
| 465 | * @param r The record to be added |
| 466 | * @see Record |
| 467 | */ |
| 468 | public void |
| 469 | addRecord(Record r) { |
| 470 | Name name = r.getName(); |
| 471 | int rtype = r.getRRsetType(); |
| 472 | synchronized (this) { |
| 473 | RRset rrset = findRRset(name, rtype); |
| 474 | if (rrset == null) { |
| 475 | rrset = new RRset(r); |
| 476 | addRRset(name, rrset); |
| 477 | } else { |
| 478 | rrset.addRR(r); |
| 479 | } |
| 480 | } |
| 481 | } |
| 482 | |
| 483 | /** |
| 484 | * Removes a record from the Zone |
| 485 | * @param r The record to be removed |
| 486 | * @see Record |
| 487 | */ |
| 488 | public void |
| 489 | removeRecord(Record r) { |
| 490 | Name name = r.getName(); |
| 491 | int rtype = r.getRRsetType(); |
| 492 | synchronized (this) { |
| 493 | RRset rrset = findRRset(name, rtype); |
| 494 | if (rrset == null) |
| 495 | return; |
| 496 | if (rrset.size() == 1 && rrset.first().equals(r)) |
| 497 | removeRRset(name, rtype); |
| 498 | else |
| 499 | rrset.deleteRR(r); |
| 500 | } |
| 501 | } |
| 502 | |
| 503 | /** |
| 504 | * Returns an Iterator over the RRsets in the zone. |
| 505 | */ |
| 506 | public Iterator |
| 507 | iterator() { |
| 508 | return new ZoneIterator(false); |
| 509 | } |
| 510 | |
| 511 | /** |
| 512 | * Returns an Iterator over the RRsets in the zone that can be used to |
| 513 | * construct an AXFR response. This is identical to {@link #iterator} except |
| 514 | * that the SOA is returned at the end as well as the beginning. |
| 515 | */ |
| 516 | public Iterator |
| 517 | AXFR() { |
| 518 | return new ZoneIterator(true); |
| 519 | } |
| 520 | |
| 521 | private void |
| 522 | nodeToString(StringBuffer sb, Object node) { |
| 523 | RRset [] sets = allRRsets(node); |
| 524 | for (int i = 0; i < sets.length; i++) { |
| 525 | RRset rrset = sets[i]; |
| 526 | Iterator it = rrset.rrs(); |
| 527 | while (it.hasNext()) |
| 528 | sb.append(it.next() + "\n"); |
| 529 | it = rrset.sigs(); |
| 530 | while (it.hasNext()) |
| 531 | sb.append(it.next() + "\n"); |
| 532 | } |
| 533 | } |
| 534 | |
| 535 | /** |
| 536 | * Returns the contents of the Zone in master file format. |
| 537 | */ |
| 538 | public synchronized String |
| 539 | toMasterFile() { |
| 540 | Iterator zentries = data.entrySet().iterator(); |
| 541 | StringBuffer sb = new StringBuffer(); |
| 542 | nodeToString(sb, originNode); |
| 543 | while (zentries.hasNext()) { |
| 544 | Map.Entry entry = (Map.Entry) zentries.next(); |
| 545 | if (!origin.equals(entry.getKey())) |
| 546 | nodeToString(sb, entry.getValue()); |
| 547 | } |
| 548 | return sb.toString(); |
| 549 | } |
| 550 | |
| 551 | /** |
| 552 | * Returns the contents of the Zone as a string (in master file format). |
| 553 | */ |
| 554 | public String |
| 555 | toString() { |
| 556 | return toMasterFile(); |
| 557 | } |
| 558 | |
| 559 | } |