J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 1999-2007 Sun Microsystems, Inc. All Rights Reserved. |
| 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 4 | * |
| 5 | * This code is free software; you can redistribute it and/or modify it |
| 6 | * under the terms of the GNU General Public License version 2 only, as |
| 7 | * published by the Free Software Foundation. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun in the LICENSE file that accompanied this code. |
| 10 | * |
| 11 | * This code is distributed in the hope that it will be useful, but WITHOUT |
| 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| 14 | * version 2 for more details (a copy is included in the LICENSE file that |
| 15 | * accompanied this code). |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License version |
| 18 | * 2 along with this work; if not, write to the Free Software Foundation, |
| 19 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| 20 | * |
| 21 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | package com.sun.jmx.snmp.agent; |
| 27 | |
| 28 | // java imports |
| 29 | // |
| 30 | import java.io.Serializable; |
| 31 | import java.util.Hashtable; |
| 32 | import java.util.Enumeration; |
| 33 | import java.util.Vector; |
| 34 | |
| 35 | // jmx imports |
| 36 | // |
| 37 | import com.sun.jmx.snmp.SnmpOid; |
| 38 | import com.sun.jmx.snmp.SnmpValue; |
| 39 | import com.sun.jmx.snmp.SnmpVarBind; |
| 40 | import com.sun.jmx.snmp.SnmpStatusException; |
| 41 | |
| 42 | // SNMP Runtime imports |
| 43 | // |
| 44 | import com.sun.jmx.snmp.agent.SnmpMibOid; |
| 45 | import com.sun.jmx.snmp.agent.SnmpMibNode; |
| 46 | |
| 47 | /** |
| 48 | * Represents a node in an SNMP MIB which corresponds to a group. |
| 49 | * This class allows subnodes to be registered below a group, providing |
| 50 | * support for nested groups. The subnodes are registered at run time |
| 51 | * when registering the nested groups in the global MIB OID tree. |
| 52 | * <P> |
| 53 | * This class is used by the class generated by <CODE>mibgen</CODE>. |
| 54 | * You should not need to use this class directly. |
| 55 | * |
| 56 | * <p><b>This API is a Sun Microsystems internal API and is subject |
| 57 | * to change without notice.</b></p> |
| 58 | */ |
| 59 | |
| 60 | public abstract class SnmpMibGroup extends SnmpMibOid |
| 61 | implements Serializable { |
| 62 | |
| 63 | // We will register the OID arcs leading to subgroups in this hashtable. |
| 64 | // So for each arc in varList, if the arc is also in subgroups, it leads |
| 65 | // to a subgroup, if it is not in subgroup, it leads either to a table |
| 66 | // or to a variable. |
| 67 | protected Hashtable<Long, Long> subgroups = null; |
| 68 | |
| 69 | /** |
| 70 | * Tells whether the given arc identifies a table in this group. |
| 71 | * |
| 72 | * @param arc An OID arc. |
| 73 | * |
| 74 | * @return <CODE>true</CODE> if `arc' leads to a table. |
| 75 | */ |
| 76 | public abstract boolean isTable(long arc); |
| 77 | |
| 78 | /** |
| 79 | * Tells whether the given arc identifies a variable (scalar object) in |
| 80 | * this group. |
| 81 | * |
| 82 | * @param arc An OID arc. |
| 83 | * |
| 84 | * @return <CODE>true</CODE> if `arc' leads to a variable. |
| 85 | */ |
| 86 | public abstract boolean isVariable(long arc); |
| 87 | |
| 88 | /** |
| 89 | * Tells whether the given arc identifies a readable scalar object in |
| 90 | * this group. |
| 91 | * |
| 92 | * @param arc An OID arc. |
| 93 | * |
| 94 | * @return <CODE>true</CODE> if `arc' leads to a readable variable. |
| 95 | */ |
| 96 | public abstract boolean isReadable(long arc); |
| 97 | |
| 98 | |
| 99 | /** |
| 100 | * Gets the table identified by the given `arc'. |
| 101 | * |
| 102 | * @param arc An OID arc. |
| 103 | * |
| 104 | * @return The <CODE>SnmpMibTable</CODE> identified by `arc', or |
| 105 | * <CODE>null</CODE> if `arc' does not identify any table. |
| 106 | */ |
| 107 | public abstract SnmpMibTable getTable(long arc); |
| 108 | |
| 109 | /** |
| 110 | * Checks whether the given OID arc identifies a variable (scalar |
| 111 | * object). |
| 112 | * |
| 113 | * @exception If the given `arc' does not identify any variable in this |
| 114 | * group, throws an SnmpStatusException. |
| 115 | */ |
| 116 | public void validateVarId(long arc, Object userData) |
| 117 | throws SnmpStatusException { |
| 118 | if (isVariable(arc) == false) |
| 119 | throw noSuchObjectException; |
| 120 | } |
| 121 | |
| 122 | |
| 123 | // ------------------------------------------------------------------- |
| 124 | // We use a hashtable (subgroup) in order to determine whether an |
| 125 | // OID arc leads to a subgroup. This implementation can be changed if |
| 126 | // needed... |
| 127 | // For instance, the subclass could provide a generated isNestedArc() |
| 128 | // method in which the subgroup OID arcs would be hardcoded. |
| 129 | // However, the generic approach was prefered because at this time |
| 130 | // groups and subgroups are dynamically registered in the MIB. |
| 131 | // |
| 132 | /** |
| 133 | * Tell whether the given OID arc identifies a sub-tree |
| 134 | * leading to a nested SNMP sub-group. This method is used internally. |
| 135 | * You shouldn't need to call it directly. |
| 136 | * |
| 137 | * @param arc An OID arc. |
| 138 | * |
| 139 | * @return <CODE>true</CODE> if the given OID arc identifies a subtree |
| 140 | * leading to a nested SNMP sub-group. |
| 141 | * |
| 142 | */ |
| 143 | public boolean isNestedArc(long arc) { |
| 144 | if (subgroups == null) return false; |
| 145 | Object obj = subgroups.get(new Long(arc)); |
| 146 | // if the arc is registered in the hashtable, |
| 147 | // it leads to a subgroup. |
| 148 | return (obj != null); |
| 149 | } |
| 150 | |
| 151 | /** |
| 152 | * Generic handling of the <CODE>get</CODE> operation. |
| 153 | * <p>The actual implementation of this method will be generated |
| 154 | * by mibgen. Usually, this implementation only delegates the |
| 155 | * job to some other provided runtime class, which knows how to |
| 156 | * access the MBean. The current toolkit thus provides two |
| 157 | * implementations: |
| 158 | * <ul><li>The standard implementation will directly access the |
| 159 | * MBean through a java reference,</li> |
| 160 | * <li>The generic implementation will access the MBean through |
| 161 | * the MBean server.</li> |
| 162 | * </ul> |
| 163 | * <p>Both implementations rely upon specific - and distinct, set of |
| 164 | * mibgen generated methods. |
| 165 | * <p> You can override this method if you need to implement some |
| 166 | * specific policies for minimizing the accesses made to some remote |
| 167 | * underlying resources. |
| 168 | * <p> |
| 169 | * |
| 170 | * @param req The sub-request that must be handled by this node. |
| 171 | * |
| 172 | * @param depth The depth reached in the OID tree. |
| 173 | * |
| 174 | * @exception SnmpStatusException An error occurred while accessing |
| 175 | * the MIB node. |
| 176 | */ |
| 177 | abstract public void get(SnmpMibSubRequest req, int depth) |
| 178 | throws SnmpStatusException; |
| 179 | |
| 180 | /** |
| 181 | * Generic handling of the <CODE>set</CODE> operation. |
| 182 | * <p>The actual implementation of this method will be generated |
| 183 | * by mibgen. Usually, this implementation only delegates the |
| 184 | * job to some other provided runtime class, which knows how to |
| 185 | * access the MBean. The current toolkit thus provides two |
| 186 | * implementations: |
| 187 | * <ul><li>The standard implementation will directly access the |
| 188 | * MBean through a java reference,</li> |
| 189 | * <li>The generic implementation will access the MBean through |
| 190 | * the MBean server.</li> |
| 191 | * </ul> |
| 192 | * <p>Both implementations rely upon specific - and distinct, set of |
| 193 | * mibgen generated methods. |
| 194 | * <p> You can override this method if you need to implement some |
| 195 | * specific policies for minimizing the accesses made to some remote |
| 196 | * underlying resources. |
| 197 | * <p> |
| 198 | * |
| 199 | * @param req The sub-request that must be handled by this node. |
| 200 | * |
| 201 | * @param depth The depth reached in the OID tree. |
| 202 | * |
| 203 | * @exception SnmpStatusException An error occurred while accessing |
| 204 | * the MIB node. |
| 205 | */ |
| 206 | abstract public void set(SnmpMibSubRequest req, int depth) |
| 207 | throws SnmpStatusException; |
| 208 | |
| 209 | /** |
| 210 | * Generic handling of the <CODE>check</CODE> operation. |
| 211 | * |
| 212 | * <p>The actual implementation of this method will be generated |
| 213 | * by mibgen. Usually, this implementation only delegates the |
| 214 | * job to some other provided runtime class, which knows how to |
| 215 | * access the MBean. The current toolkit thus provides two |
| 216 | * implementations: |
| 217 | * <ul><li>The standard implementation will directly access the |
| 218 | * MBean through a java reference,</li> |
| 219 | * <li>The generic implementation will access the MBean through |
| 220 | * the MBean server.</li> |
| 221 | * </ul> |
| 222 | * <p>Both implementations rely upon specific - and distinct, set of |
| 223 | * mibgen generated methods. |
| 224 | * <p> You can override this method if you need to implement some |
| 225 | * specific policies for minimizing the accesses made to some remote |
| 226 | * underlying resources, or if you need to implement some consistency |
| 227 | * checks between the different values provided in the varbind list. |
| 228 | * <p> |
| 229 | * |
| 230 | * @param req The sub-request that must be handled by this node. |
| 231 | * |
| 232 | * @param depth The depth reached in the OID tree. |
| 233 | * |
| 234 | * @exception SnmpStatusException An error occurred while accessing |
| 235 | * the MIB node. |
| 236 | */ |
| 237 | abstract public void check(SnmpMibSubRequest req, int depth) |
| 238 | throws SnmpStatusException; |
| 239 | |
| 240 | // -------------------------------------------------------------------- |
| 241 | // If we reach this node, we are below the root OID, so we just |
| 242 | // return. |
| 243 | // -------------------------------------------------------------------- |
| 244 | public void getRootOid(Vector result) { |
| 245 | return; |
| 246 | } |
| 247 | |
| 248 | // ------------------------------------------------------------------- |
| 249 | // PACKAGE METHODS |
| 250 | // ------------------------------------------------------------------- |
| 251 | |
| 252 | // ------------------------------------------------------------------- |
| 253 | // This method can also be overriden in a subclass to provide a |
| 254 | // different implementation of the isNestedArc() method. |
| 255 | // => if isNestedArc() is hardcoded, then registerSubArc() becomes |
| 256 | // useless and can become empty. |
| 257 | /** |
| 258 | * Register an OID arc that identifies a sub-tree |
| 259 | * leading to a nested SNMP sub-group. This method is used internally. |
| 260 | * You shouldn't ever call it directly. |
| 261 | * |
| 262 | * @param arc An OID arc. |
| 263 | * |
| 264 | */ |
| 265 | void registerNestedArc(long arc) { |
| 266 | Long obj = new Long(arc); |
| 267 | if (subgroups == null) subgroups = new Hashtable<Long, Long>(); |
| 268 | // registers the arc in the hashtable. |
| 269 | subgroups.put(obj,obj); |
| 270 | } |
| 271 | |
| 272 | // ------------------------------------------------------------------- |
| 273 | // The SnmpMibOid algorithm relies on the fact that for every arc |
| 274 | // registered in varList, there is a corresponding node at the same |
| 275 | // position in children. |
| 276 | // So the trick is to register a null node in children for each variable |
| 277 | // in varList, so that the real subgroup nodes can be inserted at the |
| 278 | // correct location. |
| 279 | // registerObject() should be called for each scalar object and each |
| 280 | // table arc by the generated subclass. |
| 281 | /** |
| 282 | * Register an OID arc that identifies a scalar object or a table. |
| 283 | * This method is used internally. You shouldn't ever call it directly. |
| 284 | * |
| 285 | * @param arc An OID arc. |
| 286 | * |
| 287 | */ |
| 288 | protected void registerObject(long arc) |
| 289 | throws IllegalAccessException { |
| 290 | |
| 291 | // this will register the variable in both varList and children |
| 292 | // The node registered in children will be null, so that the parent |
| 293 | // algorithm will behave as if no node were registered. This is a |
| 294 | // trick that makes the parent algorithm behave as if only subgroups |
| 295 | // were registered in varList and children. |
| 296 | long[] oid = new long[1]; |
| 297 | oid[0] = arc; |
| 298 | super.registerNode(oid,0,null); |
| 299 | } |
| 300 | |
| 301 | // ------------------------------------------------------------------- |
| 302 | // registerNode() will be called at runtime when nested groups are |
| 303 | // registered in the MIB. So we do know that this method will only |
| 304 | // be called to register nested-groups. |
| 305 | // We trap registerNode() in order to call registerSubArc() |
| 306 | /** |
| 307 | * Register a child node of this node in the OID tree. |
| 308 | * This method is used internally. You shouldn't ever call it directly. |
| 309 | * |
| 310 | * @param oid The oid of the node being registered. |
| 311 | * @param cursor The position reached in the oid. |
| 312 | * @param node The node being registered. |
| 313 | * |
| 314 | */ |
| 315 | void registerNode(long[] oid, int cursor ,SnmpMibNode node) |
| 316 | throws IllegalAccessException { |
| 317 | super.registerNode(oid,cursor,node); |
| 318 | if (cursor < 0) return; |
| 319 | if (cursor >= oid.length) return; |
| 320 | // if we get here, then it means we are registering a subgroup. |
| 321 | // We will thus register the sub arc in the subgroups hashtable. |
| 322 | registerNestedArc(oid[cursor]); |
| 323 | } |
| 324 | |
| 325 | // ------------------------------------------------------------------- |
| 326 | // see comments in SnmpMibNode |
| 327 | // ------------------------------------------------------------------- |
| 328 | void findHandlingNode(SnmpVarBind varbind, |
| 329 | long[] oid, int depth, |
| 330 | SnmpRequestTree handlers) |
| 331 | throws SnmpStatusException { |
| 332 | |
| 333 | int length = oid.length; |
| 334 | SnmpMibNode node = null; |
| 335 | |
| 336 | if (handlers == null) |
| 337 | throw new SnmpStatusException(SnmpStatusException.snmpRspGenErr); |
| 338 | |
| 339 | final Object data = handlers.getUserData(); |
| 340 | |
| 341 | if (depth >= length) { |
| 342 | // Nothing is left... the oid is not valid |
| 343 | throw new SnmpStatusException(SnmpStatusException.noAccess); |
| 344 | } |
| 345 | |
| 346 | long arc = oid[depth]; |
| 347 | |
| 348 | if (isNestedArc(arc)) { |
| 349 | // This arc leads to a subgroup: delegates the search to the |
| 350 | // method defined in SnmpMibOid |
| 351 | super.findHandlingNode(varbind,oid,depth,handlers); |
| 352 | return; |
| 353 | } else if (isTable(arc)) { |
| 354 | // This arc leads to a table: forward the search to the table. |
| 355 | |
| 356 | // Gets the table |
| 357 | SnmpMibTable table = getTable(arc); |
| 358 | |
| 359 | // Forward the search to the table |
| 360 | table.findHandlingNode(varbind,oid,depth+1,handlers); |
| 361 | |
| 362 | } else { |
| 363 | // If it's not a variable, throws an exception |
| 364 | validateVarId(arc, data); |
| 365 | |
| 366 | // The trailing .0 is missing in the OID |
| 367 | if (depth+2 > length) |
| 368 | throw noSuchInstanceException; |
| 369 | |
| 370 | // There are too many arcs left in the OID (there should remain |
| 371 | // a single trailing .0) |
| 372 | if (depth+2 < length) |
| 373 | throw noSuchInstanceException; |
| 374 | |
| 375 | // The last trailing arc is not .0 |
| 376 | if (oid[depth+1] != 0L) |
| 377 | throw noSuchInstanceException; |
| 378 | |
| 379 | // It's one of our variable, register this node. |
| 380 | handlers.add(this,depth,varbind); |
| 381 | } |
| 382 | } |
| 383 | |
| 384 | // ------------------------------------------------------------------- |
| 385 | // See comments in SnmpMibNode. |
| 386 | // ------------------------------------------------------------------- |
| 387 | long[] findNextHandlingNode(SnmpVarBind varbind, |
| 388 | long[] oid, int pos, int depth, |
| 389 | SnmpRequestTree handlers, AcmChecker checker) |
| 390 | throws SnmpStatusException { |
| 391 | |
| 392 | int length = oid.length; |
| 393 | SnmpMibNode node = null; |
| 394 | |
| 395 | if (handlers == null) |
| 396 | // This should be considered as a genErr, but we do not want to |
| 397 | // abort the whole request, so we're going to throw |
| 398 | // a noSuchObject... |
| 399 | // |
| 400 | throw noSuchObjectException; |
| 401 | |
| 402 | final Object data = handlers.getUserData(); |
| 403 | final int pduVersion = handlers.getRequestPduVersion(); |
| 404 | |
| 405 | |
| 406 | // The generic case where the end of the OID has been reached is |
| 407 | // handled in the superclass |
| 408 | // XXX Revisit: this works but it is somewhat convoluted. Just setting |
| 409 | // arc to -1 would work too. |
| 410 | if (pos >= length) |
| 411 | return super.findNextHandlingNode(varbind,oid,pos,depth, |
| 412 | handlers, checker); |
| 413 | |
| 414 | // Ok, we've got the arc. |
| 415 | long arc = oid[pos]; |
| 416 | |
| 417 | long[] result = null; |
| 418 | |
| 419 | // We have a recursive logic. Should we have a loop instead? |
| 420 | try { |
| 421 | |
| 422 | if (isTable(arc)) { |
| 423 | // If the arc identifies a table, then we need to forward |
| 424 | // the search to the table. |
| 425 | |
| 426 | // Gets the table identified by `arc' |
| 427 | SnmpMibTable table = getTable(arc); |
| 428 | |
| 429 | // Forward to the table |
| 430 | checker.add(depth, arc); |
| 431 | try { |
| 432 | result = table.findNextHandlingNode(varbind,oid,pos+1, |
| 433 | depth+1,handlers, |
| 434 | checker); |
| 435 | }catch(SnmpStatusException ex) { |
| 436 | throw noSuchObjectException; |
| 437 | } finally { |
| 438 | checker.remove(depth); |
| 439 | } |
| 440 | // Build up the leaf OID |
| 441 | result[depth] = arc; |
| 442 | return result; |
| 443 | } else if (isReadable(arc)) { |
| 444 | // If the arc identifies a readable variable, then two cases: |
| 445 | |
| 446 | if (pos == (length - 1)) { |
| 447 | // The end of the OID is reached, so we return the leaf |
| 448 | // corresponding to the variable identified by `arc' |
| 449 | |
| 450 | // Build up the OID |
| 451 | // result = new SnmpOid(0); |
| 452 | // result.insert((int)arc); |
| 453 | result = new long[depth+2]; |
| 454 | result[depth+1] = 0L; |
| 455 | result[depth] = arc; |
| 456 | |
| 457 | checker.add(depth, result, depth, 2); |
| 458 | try { |
| 459 | checker.checkCurrentOid(); |
| 460 | } catch(SnmpStatusException e) { |
| 461 | throw noSuchObjectException; |
| 462 | } finally { |
| 463 | checker.remove(depth,2); |
| 464 | } |
| 465 | |
| 466 | // Registers this node |
| 467 | handlers.add(this,depth,varbind); |
| 468 | return result; |
| 469 | } |
| 470 | |
| 471 | // The end of the OID is not yet reached, so we must return |
| 472 | // the next leaf following the variable identified by `arc'. |
| 473 | // We cannot return the variable because whatever follows in |
| 474 | // the OID will be greater or equals to 0, and 0 identifies |
| 475 | // the variable itself - so we have indeed to return the |
| 476 | // next object. |
| 477 | // So we do nothing, because this case is handled at the |
| 478 | // end of the if ... else if ... else ... block. |
| 479 | |
| 480 | } else if (isNestedArc(arc)) { |
| 481 | // Now if the arc leads to a subgroup, we delegate the |
| 482 | // search to the child, just as done in SnmpMibNode. |
| 483 | // |
| 484 | |
| 485 | // get the child ( = nested arc node). |
| 486 | // |
| 487 | final SnmpMibNode child = getChild(arc); |
| 488 | |
| 489 | if (child != null) { |
| 490 | checker.add(depth, arc); |
| 491 | try { |
| 492 | result = child.findNextHandlingNode(varbind,oid,pos+1, |
| 493 | depth+1,handlers, |
| 494 | checker); |
| 495 | result[depth] = arc; |
| 496 | return result; |
| 497 | } finally { |
| 498 | checker.remove(depth); |
| 499 | } |
| 500 | } |
| 501 | } |
| 502 | |
| 503 | // The oid is not valid, we will throw an exception in order |
| 504 | // to try with the next valid identifier... |
| 505 | // |
| 506 | throw noSuchObjectException; |
| 507 | |
| 508 | } catch (SnmpStatusException e) { |
| 509 | // We didn't find anything at the given arc, so we're going |
| 510 | // to try with the next valid arc |
| 511 | // |
| 512 | long[] newOid = new long[1]; |
| 513 | newOid[0] = getNextVarId(arc,data,pduVersion); |
| 514 | return findNextHandlingNode(varbind,newOid,0,depth, |
| 515 | handlers,checker); |
| 516 | } |
| 517 | } |
| 518 | |
| 519 | } |