xref: /illumos-gate/usr/src/lib/libslp/javalib/com/sun/slp/SunDATable.java (revision e7cbe64f7a72dae5cb44f100db60ca88f3313c65)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
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18  * information: Portions Copyright [yyyy] [name of copyright owner]
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22 /*
23  * ident	"%Z%%M%	%I%	%E% SMI"
24  *
25  * Copyright 2001,2003 Sun Microsystems, Inc.  All rights reserved.
26  * Use is subject to license terms.
27  *
28  */
29 
30 //  SCCS Status:      %W%	%G%
31 //  SunDATable.java: A DATable implementation that uses the IPC connection.
32 //  Author:           James Kempf
33 //  Created On:       Mon May 11 15:00:23 1998
34 //  Last Modified By: James Kempf
35 //  Last Modified On: Thu Mar 11 15:00:58 1999
36 //  Update Count:     71
37 //
38 
39 package com.sun.slp;
40 
41 import java.util.*;
42 import java.net.*;
43 import java.io.*;
44 
45 /**
46  * The SunDATable class uses the IPC connection to obtain DA information
47  * from the SA server. By convention, the SA server answers service
48  * requests for the service type "directory-agent.sun" and including
49  * a filter for the scopes formatted as:
50  *
51  *   "(&(|(scopes=<scope1>)(scopes=<scope2>)(scopes=<scope3>)...)(version=2))"
52  *
53  * with a collection of URLs that fit the request. The scope of the
54  * request is the hostname of the local machine, which will not be
55  * forwarded to any DAs. The URLs contain the
56  * DA IP address in the host field and a list of scopes in the URL
57  * part in the form of an attribute value assignment, i.e.:
58  *
59  *   service:directory-agent.sun:// 199.200.200.5/scopes=eng, corp, freeb
60  *
61  * The DA/scope table is initially obtained for all scopes in the
62  * useScopes list, then refreshed periodically when the
63  * time stamp runs out. The time stamp is determined as the minimum
64  * expiration time of the service URLs.
65  *
66  * @version %R%.%L% %D%
67  * @author James Kempf
68  */
69 
70 class SunDATable extends DATable {
71 
72     // The scopes identifier.
73 
74     final static String SCOPES_ID = "424242SUN-TABLE-SCOPES424242";
75 
76     // DA version number.
77 
78     final static String VERSION_ID = "424242SUN-TABLE-VERSION424242";
79 
80     // The scopes which reside on the SA only.
81 
82     private Vector saOnlyScopes = new Vector();
83 
84     // The cached vector of DA equivalence classes.
85 
86     private Vector cache = null;
87 
88     // The time when the cache should be refreshed.
89 
90     private long timeStamp = -1;
91 
92     /**
93      * Construct a DATable. We get a cached table of accessable
94      * DAs and scopes and the SA scope names to use for querying.
95      */
96 
97     SunDATable() throws ServiceLocationException {
98 
99 	// Remove the common scopes from the SA scopes. This will leave
100 	//  the private, SA only scopes.
101 
102 	saOnlyScopes = conf.getSAOnlyScopes();
103 
104 	Assert.slpassert(saOnlyScopes.size() > 0,
105 		      "no_sa_scopes",
106 		      new Object[0]);
107 
108 	// Initialize the cache. We want the scopes that can be dynamically
109 	//  discovered. If we have been configured with scopes, then
110 	//  it will be those. If not, then we want whatever we can discovery.
111 	//  we only want the default version for client side.
112 
113 	cache = getWireTable(conf.getConfiguredScopes(), Defaults.version);
114 
115     }
116 
117     /**
118      * Return a hashtable of DA equivalence classes and multicast
119      * scopes. Multicast scopes are stored in the special hashtable
120      * key MULTICAST_KEY. Unicast DA equivalence classes are stored
121      * under the key UNICAST_KEY.
122      *
123      * @param scopes Scope list for DAs needed.
124      * @return Hashtable with DA addresses as keys and scopes to contact
125      *         them with as values. Any scopes not associated with a
126      *         DA come back stored under the key MULTICAST_KEY.
127      *         Unicast DA equivalence classes are stored
128      * 	     under the key UNICAST_KEY.
129      */
130 
131     synchronized Hashtable findDAScopes(Vector scopes)
132 	throws ServiceLocationException {
133 
134 	Hashtable ret = new Hashtable();
135 
136 	Vector equivClasses = null;
137 
138 	// Refresh the local cache if necessary.
139 
140 	if (timeStamp <= System.currentTimeMillis()) {
141 	    Vector useScopes = conf.getConfiguredScopes();
142 
143 	    cache = getWireTable(useScopes, Defaults.version);
144 
145 	}
146 
147 	equivClasses = (Vector)cache.clone();
148 	int i;
149 
150 	// Sort through the local cache, matching against the input parameter.
151 	//  Collect multicast scopes.
152 
153 	Vector multicastScopes = (Vector)scopes.clone();
154 
155 	for (i = 0; i < equivClasses.size(); i++) {
156 	    DARecord rec = (DARecord)equivClasses.elementAt(i);
157 	    Vector daScopes = (Vector)rec.scopes.clone();
158 
159 	    // Filter multicast scopes first. Remove any from the multicast
160 	    //  scope list that are in daScopes.
161 
162 	    filterScopes(multicastScopes, daScopes, true);
163 
164 	    // Now filter daScopes. Remove any from the daScopes that are
165 	    // not in the input scopes.
166 
167 	    filterScopes(daScopes, scopes, false);
168 
169 	    // Remove this record if there are none left.
170 
171 	    if (daScopes.size() <= 0) {
172 		/*
173 		 *  Must decrement the index 'i' otherwise the next iteration
174 		 *  around the loop will miss the element immediately after
175 		 *  the element removed.
176 		 *
177 		 *  WARNING: Do not use 'i' again until the loop has
178 		 *           iterated as it may, after decrementing,
179 		 *           be negative.
180 		 */
181 		equivClasses.removeElementAt(i);
182 		i--;
183 		continue;
184 	    }
185 	}
186 
187 	// Install the unicast and multicast scopes if any.
188 
189 	if (multicastScopes.size() > 0) {
190 	    ret.put(MULTICAST_KEY, multicastScopes);
191 
192 	}
193 
194 	if (equivClasses.size() > 0) {
195 	    ret.put(UNICAST_KEY, equivClasses);
196 
197 	}
198 
199 	return ret;
200 
201     }
202 
203     /**
204      * Remove a DA by address. We only remove it from the wire table
205      * so if it's down temporarily, we'll get it back again.
206      *
207      * @param address The host address of the DA.
208      * @param scopes The scopes.
209      * @return True if removed, false if not.
210      */
211 
212     boolean removeDA(InetAddress address, Vector scopes) {
213 
214 	// Sort through the table of equivalence classes in cache.
215 
216 	boolean foundit = false;
217 	int i;
218 
219 	for (i = 0; i < cache.size(); i++) {
220 	    DARecord rec = (DARecord)cache.elementAt(i);
221 	    Vector daAddresses = rec.daAddresses;
222 
223 	    // Ignore scopes, delete if there. Scopes will always be the
224 	    //  ones for which this DA is to be removed.
225 
226 	    int j, m = daAddresses.size();
227 
228 	    for (j = 0; j < m; j++) {
229 		InetAddress daaddr = (InetAddress)daAddresses.elementAt(j);
230 
231 		// If they are equal, remove it, exit loop.
232 
233 		if (address.equals(daaddr)) {
234 		    foundit = true;
235 		    daAddresses.removeElementAt(j);
236 
237 		    // If the cache entry is empty, remove it.
238 
239 		    if (daAddresses.size() <= 0) {
240 			cache.removeElementAt(i);
241 
242 		    }
243 
244 		    break;
245 
246 		}
247 	    }
248 	}
249 
250 	return foundit;
251 
252     }
253 
254     // Return a vector of DARecord equivalence classes by going out to the
255     //  wire for them. Merge any that are in the current process'
256     //  DAAddresses property.
257 
258     private Vector getWireTable(Vector scopes, int version)
259 	throws ServiceLocationException {
260 
261 	Vector ret = new Vector();
262 
263 	// Get replies from the SA server. These will be CSrvMsg replies.
264 
265 	CSrvMsg msg = getSrvReply(scopes, version);
266 
267 	// Process reply into the vector of equivalence classes by adding to
268 	// to those from the preconfigured DAs.
269 
270 	processReply(msg, ret);
271 
272 	// Return vector.
273 
274 	return ret;
275     }
276 
277     private CSrvMsg getSrvReply(Vector scopes, int version)
278 	throws ServiceLocationException {
279 
280 	// Form the query.
281 
282 	StringBuffer buf = new StringBuffer();
283 	int i, n = scopes.size();
284 
285 	for (i = 0; i < n; i++) {
286 	    buf.append("(");
287 	    buf.append(SCOPES_ID);
288 	    buf.append("=");
289 	    buf.append((String)scopes.elementAt(i));
290 	    buf.append(")");
291 	}
292 
293 	// Add logical disjunction if there is more than one scope.
294 
295 	if (i > 1) {
296 	    buf.insert(0, "(|");
297 	    buf.append(")");
298 
299 	}
300 
301 	// Add version number restriction.
302 
303 	if (i > 0) {
304 	    buf.insert(0, "(&");
305 
306 	}
307 
308 	buf.append("(");
309 	buf.append(VERSION_ID);
310 	buf.append("=");
311 	buf.append((new Integer(version)).toString());
312 	buf.append(")");
313 
314 	// Add closing paren if there were any scopes.
315 
316 	if (i > 0) {
317 	    buf.append(")");
318 
319 	}
320 
321 	// Create the message object. Note that if scope vector is
322 	//  empty, the query is the null string, and so all DAs
323 	//  will be returned.
324 
325 	CSrvMsg msg = new CSrvMsg(Defaults.locale,
326 				  Defaults.SUN_DA_SERVICE_TYPE,
327 				  saOnlyScopes,
328 				  buf.toString());
329 
330 	// Send it down the pipe to the IPC process. It's a bad bug
331 	//  if the reply comes back as not a CSrvMsg.
332 
333 	SrvLocMsg rply =
334 	    Transact.transactTCPMsg(conf.getLoopback(), msg, true);
335 
336 	// Check error code.
337 
338 	if (rply == null ||
339 	    rply.getErrorCode() != ServiceLocationException.OK) {
340 	    short errCode =
341 		(rply == null ?
342 		 ServiceLocationException.INTERNAL_SYSTEM_ERROR :
343 		 rply.getErrorCode());
344 	    throw
345 		new ServiceLocationException(errCode,
346 					     "loopback_error",
347 					     new Object[] {
348 		    new Short(errCode)});
349 
350 	}
351 
352 	return (CSrvMsg)rply;
353     }
354 
355     // Process CSrvMsg reply into DA equivalence class vector
356 
357     private void processReply(CSrvMsg msg, Vector ret)
358 	throws ServiceLocationException {
359 
360 	int shortTimer = Integer.MAX_VALUE;
361 
362 	// Get the URLs.
363 
364 	Vector serviceURLs = msg.serviceURLs;
365 
366 	// Process each service URL.
367 
368 	int i, n = serviceURLs.size();
369 
370 	for (i = 0; i < n; i++) {
371 	    ServiceURL url = (ServiceURL)serviceURLs.elementAt(i);
372 
373 	    // If the time to live is less than the current minimum,
374 	    //  save it.
375 
376 	    int lifetime = url.getLifetime();
377 
378 	    if (lifetime < shortTimer) {
379 		shortTimer = lifetime;
380 
381 	    }
382 
383 	    // Get the host name and URL part.
384 
385 	    String daaddr = url.getHost();
386 	    String urlpart = url.getURLPath();
387 
388 	    // Parse URL part into scope list. Be
389 	    //  sure not to include the initial `/' in the parse.
390 
391 	    StringTokenizer tk =
392 		new StringTokenizer(urlpart.substring(1,
393 						      urlpart.length()),
394 				    ";");
395 	    Vector daScopes = null;
396 
397 	    while (tk.hasMoreElements()) {
398 		String attrExp = tk.nextToken();
399 
400 		// Convert to an SLP attribute.
401 
402 		ServiceLocationAttribute attr =
403 		    new ServiceLocationAttribute("(" + attrExp + ")", false);
404 
405 		// Depending on the attribute id, do something.
406 
407 		String id = attr.getId();
408 		Vector vals = attr.getValues();
409 
410 		if (id.equals(SCOPES_ID)) {
411 		    daScopes = vals;
412 
413 		} else {
414 		    throw
415 			new ServiceLocationException(
416 				ServiceLocationException.PARSE_ERROR,
417 				"loopback_parse_error",
418 				new Object[] {url});
419 		}
420 	    }
421 
422 	    // Add it to the equivalence class.
423 
424 	    addToEquivClass(daaddr, daScopes, ret);
425 
426 	}
427 
428 	// Reset the timestamp.
429 
430 	timeStamp = System.currentTimeMillis() + (long)(shortTimer * 1000);
431 
432     }
433 
434 }
435