Config.java 45.2 KB
Newer Older
D
duke 已提交
1
/*
2
 * Copyright (c) 2000, 2012, Oracle and/or its affiliates. All rights reserved.
D
duke 已提交
3 4 5 6
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
7
 * published by the Free Software Foundation.  Oracle designates this
D
duke 已提交
8
 * particular file as subject to the "Classpath" exception as provided
9
 * by Oracle in the LICENSE file that accompanied this code.
D
duke 已提交
10 11 12 13 14 15 16 17 18 19 20
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
21 22 23
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
D
duke 已提交
24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43
 */

/*
 *
 *  (C) Copyright IBM Corp. 1999 All Rights Reserved.
 *  Copyright 1997 The Open Group Research Institute.  All rights reserved.
 */
package sun.security.krb5;

import java.io.File;
import java.io.FileInputStream;
import java.util.Hashtable;
import java.util.Vector;
import java.util.ArrayList;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.IOException;
import java.util.StringTokenizer;
import java.net.InetAddress;
import java.net.UnknownHostException;
W
weijun 已提交
44 45 46
import java.security.AccessController;
import java.security.PrivilegedExceptionAction;
import java.util.Arrays;
47
import java.util.List;
W
weijun 已提交
48
import java.util.Locale;
49
import sun.net.dns.ResolverConfiguration;
D
duke 已提交
50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
import sun.security.krb5.internal.crypto.EType;
import sun.security.krb5.internal.Krb5;

/**
 * This class maintains key-value pairs of Kerberos configurable constants
 * from configuration file or from user specified system properties.
 */

public class Config {

    /*
     * Only allow a single instance of Config.
     */
    private static Config singleton = null;

    /*
66
     * Hashtable used to store configuration information.
D
duke 已提交
67
     */
W
weijun 已提交
68
    private Hashtable<String,Object> stanzaTable = new Hashtable<>();
D
duke 已提交
69 70 71 72 73 74 75 76

    private static boolean DEBUG = sun.security.krb5.internal.Krb5.DEBUG;

    // these are used for hexdecimal calculation.
    private static final int BASE16_0 = 1;
    private static final int BASE16_1 = 16;
    private static final int BASE16_2 = 16 * 16;
    private static final int BASE16_3 = 16 * 16 * 16;
77 78 79 80 81 82

    /**
     * Specified by system properties. Must be both null or non-null.
     */
    private final String defaultRealm;
    private final String defaultKDC;
D
duke 已提交
83 84

    // used for native interface
85
    private static native String getWindowsDirectory(boolean isSystem);
D
duke 已提交
86 87 88 89 90 91 92


    /**
     * Gets an instance of Config class. One and only one instance (the
     * singleton) is returned.
     *
     * @exception KrbException if error occurs when constructing a Config
93 94
     * instance. Possible causes would be either of java.security.krb5.realm or
     * java.security.krb5.kdc not specified, error reading configuration file.
D
duke 已提交
95 96 97 98 99 100 101 102 103 104 105
     */
    public static synchronized Config getInstance() throws KrbException {
        if (singleton == null) {
            singleton = new Config();
        }
        return singleton;
    }

    /**
     * Refresh and reload the Configuration. This could involve,
     * for example reading the Configuration file again or getting
W
weijun 已提交
106 107 108
     * the java.security.krb5.* system properties again. This method
     * also tries its best to update static fields in other classes
     * that depend on the configuration.
D
duke 已提交
109 110
     *
     * @exception KrbException if error occurs when constructing a Config
111 112
     * instance. Possible causes would be either of java.security.krb5.realm or
     * java.security.krb5.kdc not specified, error reading configuration file.
D
duke 已提交
113 114 115 116
     */

    public static synchronized void refresh() throws KrbException {
        singleton = new Config();
117
        KdcComm.initStatic();
W
weijun 已提交
118 119
        EType.initStatic();
        Checksum.initStatic();
D
duke 已提交
120 121 122
    }


123 124
    private static boolean isMacosLionOrBetter() {
        // split the "10.x.y" version number
125 126 127 128 129 130
        String osname = getProperty("os.name");
        if (!osname.contains("OS X")) {
            return false;
        }

        String osVersion = getProperty("os.version");
131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147
        String[] fragments = osVersion.split("\\.");

        // sanity check the "10." part of the version
        if (!fragments[0].equals("10")) return false;
        if (fragments.length < 2) return false;

        // check if Mac OS X 10.7(.y)
        try {
            int minorVers = Integer.parseInt(fragments[1]);
            if (minorVers >= 7) return true;
        } catch (NumberFormatException e) {
            // was not an integer
        }

        return false;
    }

D
duke 已提交
148 149 150 151 152
    /**
     * Private constructor - can not be instantiated externally.
     */
    private Config() throws KrbException {
        /*
153
         * If either one system property is specified, we throw exception.
D
duke 已提交
154
         */
155
        String tmp = getProperty("java.security.krb5.kdc");
156 157 158 159 160 161
        if (tmp != null) {
            // The user can specify a list of kdc hosts separated by ":"
            defaultKDC = tmp.replace(':', ' ');
        } else {
            defaultKDC = null;
        }
162
        defaultRealm = getProperty("java.security.krb5.realm");
163 164
        if ((defaultKDC == null && defaultRealm != null) ||
            (defaultRealm == null && defaultKDC != null)) {
D
duke 已提交
165 166 167 168 169
            throw new KrbException
                ("System property java.security.krb5.kdc and " +
                 "java.security.krb5.realm both must be set or " +
                 "neither must be set.");
        }
170

171
        // Always read the Kerberos configuration file
172
        try {
W
weijun 已提交
173
            List<String> configFile;
174 175 176
            String fileName = getJavaFileName();
            if (fileName != null) {
                configFile = loadConfigFile(fileName);
177
                stanzaTable = parseStanzaTable(configFile);
178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201
                if (DEBUG) {
                    System.out.println("Loaded from Java config");
                }
            } else {
                boolean found = false;
                if (isMacosLionOrBetter()) {
                    try {
                        stanzaTable = SCDynamicStoreConfig.getConfig();
                        if (DEBUG) {
                            System.out.println("Loaded from SCDynamicStoreConfig");
                        }
                        found = true;
                    } catch (IOException ioe) {
                        // OK. Will go on with file
                    }
                }
                if (!found) {
                    fileName = getNativeFileName();
                    configFile = loadConfigFile(fileName);
                    stanzaTable = parseStanzaTable(configFile);
                    if (DEBUG) {
                        System.out.println("Loaded from native config");
                    }
                }
202
            }
203
        } catch (IOException ioe) {
W
weijun 已提交
204 205
            // I/O error, mostly like krb5.conf missing.
            // No problem. We'll use DNS or system property etc.
D
duke 已提交
206 207 208 209
        }
    }

    /**
W
weijun 已提交
210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226
     * Gets the last-defined string value for the specified keys.
     * @param keys the keys, as an array from section name, sub-section names
     * (if any), to value name.
     * @return the value. When there are multiple values for the same key,
     * returns the last one. {@code null} is returned if not all the keys are
     * defined. For example, {@code get("libdefaults", "forwardable")} will
     * return null if "forwardable" is not defined in [libdefaults], and
     * {@code get("realms", "R", "kdc")} will return null if "R" is not
     * defined in [realms] or "kdc" is not defined for "R".
     * @throws IllegalArgumentException if any of the keys is illegal, either
     * because a key not the last one is not a (sub)section name or the last
     * key is still a section name. For example, {@code get("libdefaults")}
     * throws this exception because [libdefaults] is a section name instead of
     * a value name, and {@code get("libdefaults", "forwardable", "tail")}
     * also throws this exception because "forwardable" is already a value name
     * and has no sub-key at all (given "forwardable" is defined, otherwise,
     * this method has no knowledge if it's a value name or a section name),
D
duke 已提交
227
     */
W
weijun 已提交
228
    public String get(String... keys) {
229
        Vector<String> v = getString0(keys);
W
weijun 已提交
230 231 232 233 234 235
        if (v == null) return null;
        return v.lastElement();
    }

    /**
     * Gets all values for the specified keys.
236 237
     * @throws IllegalArgumentException if any of the keys is illegal
     *         (See {@link #get})
W
weijun 已提交
238 239
     */
    public String getAll(String... keys) {
240
        Vector<String> v = getString0(keys);
W
weijun 已提交
241 242 243 244 245 246 247 248 249
        if (v == null) return null;
        StringBuilder sb = new StringBuilder();
        boolean first = true;
        for (String s: v) {
            if (first) {
                sb.append(s);
                first = false;
            } else {
                sb.append(' ').append(s);
D
duke 已提交
250 251
            }
        }
W
weijun 已提交
252 253 254
        return sb.toString();
    }

255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275
    /**
     * Returns true if keys exists, can be either final string(s) or sub-stanza
     * @throws IllegalArgumentException if any of the keys is illegal
     *         (See {@link #get})
     */
    public boolean exists(String... keys) {
        return get0(keys) != null;
    }

    // Returns final string value(s) for given keys.
    @SuppressWarnings("unchecked")
    private Vector<String> getString0(String... keys) {
        try {
            return (Vector<String>)get0(keys);
        } catch (ClassCastException cce) {
            throw new IllegalArgumentException(cce);
        }
    }

    // Internal method. Returns the value for keys, which can be a sub-stanza
    // or final string value(s).
W
weijun 已提交
276 277
    // The only method (except for toString) that reads stanzaTable directly.
    @SuppressWarnings("unchecked")
278
    private Object get0(String... keys) {
W
weijun 已提交
279 280 281 282 283 284
        Object current = stanzaTable;
        try {
            for (String key: keys) {
                current = ((Hashtable<String,Object>)current).get(key);
                if (current == null) return null;
            }
285
            return current;
W
weijun 已提交
286 287 288
        } catch (ClassCastException cce) {
            throw new IllegalArgumentException(cce);
        }
D
duke 已提交
289 290 291
    }

    /**
W
weijun 已提交
292 293 294 295 296 297
     * Gets the int value for the specified keys.
     * @param keys the keys
     * @return the int value, Integer.MIN_VALUE is returned if it cannot be
     * found or the value is not a legal integer.
     * @throw IllegalArgumentException if any of the keys is illegal
     * @see #get(java.lang.String[])
D
duke 已提交
298
     */
W
weijun 已提交
299 300
    public int getIntValue(String... keys) {
        String result = get(keys);
D
duke 已提交
301 302 303 304 305 306 307
        int value = Integer.MIN_VALUE;
        if (result != null) {
            try {
                value = parseIntValue(result);
            } catch (NumberFormatException e) {
                if (DEBUG) {
                    System.out.println("Exception in getting value of " +
W
weijun 已提交
308 309 310
                                       Arrays.toString(keys) + " " +
                                       e.getMessage());
                    System.out.println("Setting " + Arrays.toString(keys) +
D
duke 已提交
311 312 313 314 315 316 317 318 319
                                       " to minimum value");
                }
                value = Integer.MIN_VALUE;
            }
        }
        return value;
    }

    /**
W
weijun 已提交
320 321 322 323 324 325
     * Gets the boolean value for the specified keys.
     * @param keys the keys
     * @return the boolean value, false is returned if it cannot be
     * found or the value is not "true" (case insensitive).
     * @throw IllegalArgumentException if any of the keys is illegal
     * @see #get(java.lang.String[])
D
duke 已提交
326
     */
W
weijun 已提交
327 328
    public boolean getBooleanValue(String... keys) {
        String val = get(keys);
D
duke 已提交
329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452
        if (val != null && val.equalsIgnoreCase("true")) {
            return true;
        } else {
            return false;
        }
    }

    /**
     * Parses a string to an integer. The convertible strings include the
     * string representations of positive integers, negative integers, and
     * hex decimal integers.  Valid inputs are, e.g., -1234, +1234,
     * 0x40000.
     *
     * @param input the String to be converted to an Integer.
     * @return an numeric value represented by the string
     * @exception NumberFormationException if the String does not contain a
     * parsable integer.
     */
    private int parseIntValue(String input) throws NumberFormatException {
        int value = 0;
        if (input.startsWith("+")) {
            String temp = input.substring(1);
            return Integer.parseInt(temp);
        } else if (input.startsWith("0x")) {
            String temp = input.substring(2);
            char[] chars = temp.toCharArray();
            if (chars.length > 8) {
                throw new NumberFormatException();
            } else {
                for (int i = 0; i < chars.length; i++) {
                    int index = chars.length - i - 1;
                    switch (chars[i]) {
                    case '0':
                        value += 0;
                        break;
                    case '1':
                        value += 1 * getBase(index);
                        break;
                    case '2':
                        value += 2 * getBase(index);
                        break;
                    case '3':
                        value += 3 * getBase(index);
                        break;
                    case '4':
                        value += 4 * getBase(index);
                        break;
                    case '5':
                        value += 5 * getBase(index);
                        break;
                    case '6':
                        value += 6 * getBase(index);
                        break;
                    case '7':
                        value += 7 * getBase(index);
                        break;
                    case '8':
                        value += 8 * getBase(index);
                        break;
                    case '9':
                        value += 9 * getBase(index);
                        break;
                    case 'a':
                    case 'A':
                        value += 10 * getBase(index);
                        break;
                    case 'b':
                    case 'B':
                        value += 11 * getBase(index);
                        break;
                    case 'c':
                    case 'C':
                        value += 12 * getBase(index);
                        break;
                    case 'd':
                    case 'D':
                        value += 13 * getBase(index);
                        break;
                    case 'e':
                    case 'E':
                        value += 14 * getBase(index);
                        break;
                    case 'f':
                    case 'F':
                        value += 15 * getBase(index);
                        break;
                    default:
                        throw new NumberFormatException("Invalid numerical format");
                    }
                }
            }
            if (value < 0) {
                throw new NumberFormatException("Data overflow.");
            }
        } else {
            value = Integer.parseInt(input);
        }
        return value;
    }

    private int getBase(int i) {
        int result = 16;
        switch (i) {
        case 0:
            result = BASE16_0;
            break;
        case 1:
            result = BASE16_1;
            break;
        case 2:
            result = BASE16_2;
            break;
        case 3:
            result = BASE16_3;
            break;
        default:
            for (int j = 1; j < i; j++) {
                result *= 16;
            }
        }
        return result;
    }

    /**
W
weijun 已提交
453
     * Reads lines to the memory from the configuration file.
D
duke 已提交
454 455 456 457 458 459
     *
     * Configuration file contains information about the default realm,
     * ticket parameters, location of the KDC and the admin server for
     * known realms, etc. The file is divided into sections. Each section
     * contains one or more name/value pairs with one pair per line. A
     * typical file would be:
W
weijun 已提交
460
     * <pre>
D
duke 已提交
461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477
     * [libdefaults]
     *          default_realm = EXAMPLE.COM
     *          default_tgs_enctypes = des-cbc-md5
     *          default_tkt_enctypes = des-cbc-md5
     * [realms]
     *          EXAMPLE.COM = {
     *                  kdc = kerberos.example.com
     *                  kdc = kerberos-1.example.com
     *                  admin_server = kerberos.example.com
     *                  }
     *          SAMPLE_COM = {
     *                  kdc = orange.sample.com
     *                  admin_server = orange.sample.com
     *                  }
     * [domain_realm]
     *          blue.sample.com = TEST.SAMPLE.COM
     *          .backup.com     = EXAMPLE.COM
W
weijun 已提交
478 479 480 481 482 483 484 485 486
     * </pre>
     * @return an ordered list of strings representing the config file after
     * some initial processing, including:<ol>
     * <li> Comment lines and empty lines are removed
     * <li> "{" not at the end of a line is appended to the previous line
     * <li> The content of a section is also placed between "{" and "}".
     * <li> Lines are trimmed</ol>
     * @throws IOException if there is an I/O error
     * @throws KrbException if there is a file format error
D
duke 已提交
487
     */
W
weijun 已提交
488 489
    private List<String> loadConfigFile(final String fileName)
            throws IOException, KrbException {
D
duke 已提交
490
        try {
W
weijun 已提交
491 492 493 494 495 496 497 498 499
            List<String> v = new ArrayList<>();
            try (BufferedReader br = new BufferedReader(new InputStreamReader(
                AccessController.doPrivileged(
                    new PrivilegedExceptionAction<FileInputStream> () {
                        public FileInputStream run() throws IOException {
                            return new FileInputStream(fileName);
                        }
                    })))) {
                String line;
D
duke 已提交
500
                String previous = null;
W
weijun 已提交
501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527
                while ((line = br.readLine()) != null) {
                    line = line.trim();
                    if (line.startsWith("#") || line.isEmpty()) {
                        // ignore comments and blank line
                        // Comments start with #.
                        continue;
                    }
                    // In practice, a subsection might look like:
                    //      [realms]
                    //      EXAMPLE.COM =
                    //      {
                    //          kdc = kerberos.example.com
                    //          ...
                    //      }
                    // Before parsed into stanza table, it needs to be
                    // converted into a canonicalized style (no indent):
                    //      realms = {
                    //          EXAMPLE.COM = {
                    //              kdc = kerberos.example.com
                    //              ...
                    //          }
                    //      }
                    //
                    if (line.startsWith("[")) {
                        if (!line.endsWith("]")) {
                            throw new KrbException("Illegal config content:"
                                    + line);
D
duke 已提交
528
                        }
W
weijun 已提交
529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557
                        if (previous != null) {
                            v.add(previous);
                            v.add("}");
                        }
                        String title = line.substring(
                                1, line.length()-1).trim();
                        if (title.isEmpty()) {
                            throw new KrbException("Illegal config content:"
                                    + line);
                        }
                        previous = title + " = {";
                    } else if (line.startsWith("{")) {
                        if (previous == null) {
                            throw new KrbException(
                                "Config file should not start with \"{\"");
                        }
                        previous += " {";
                        if (line.length() > 1) {
                            // { and content on the same line
                            v.add(previous);
                            previous = line.substring(1).trim();
                        }
                    } else {
                        if (previous == null) {
                            throw new KrbException(
                                "Config file must starts with a section");
                        }
                        v.add(previous);
                        previous = line;
D
duke 已提交
558 559 560
                    }
                }
                if (previous != null) {
W
weijun 已提交
561 562
                    v.add(previous);
                    v.add("}");
D
duke 已提交
563 564
                }
            }
W
weijun 已提交
565
            return v;
D
duke 已提交
566 567 568 569 570 571 572 573 574 575
        } catch (java.security.PrivilegedActionException pe) {
            throw (IOException)pe.getException();
        }
    }

    /**
     * Parses stanza names and values from configuration file to
     * stanzaTable (Hashtable). Hashtable key would be stanza names,
     * (libdefaults, realms, domain_realms, etc), and the hashtable value
     * would be another hashtable which contains the key-value pairs under
W
weijun 已提交
576 577 578 579 580 581 582 583 584 585 586 587 588 589 590
     * a stanza name. The value of this sub-hashtable can be another hashtable
     * containing another sub-sub-section or a vector of strings for
     * final values (even if there is only one value defined).
     * <p>
     * For duplicates section names, the latter overwrites the former. For
     * duplicate value names, the values are in a vector in its appearing order.
     * </ol>
     * Please note that this behavior is Java traditional. and it is
     * not the same as the MIT krb5 behavior, where:<ol>
     * <li>Duplicated root sections will be merged
     * <li>For duplicated sub-sections, the former overwrites the latter
     * <li>Duplicate keys for values are always saved in a vector
     * </ol>
     * @param v the strings in the file, never null, might be empty
     * @throws KrbException if there is a file format error
D
duke 已提交
591
     */
W
weijun 已提交
592 593 594 595 596 597 598 599 600 601 602 603 604 605
    @SuppressWarnings("unchecked")
    private Hashtable<String,Object> parseStanzaTable(List<String> v)
            throws KrbException {
        Hashtable<String,Object> current = stanzaTable;
        for (String line: v) {
            // There are 3 kinds of lines
            // 1. a = b
            // 2. a = {
            // 3. }
            if (line.equals("}")) {
                // Go back to parent, see below
                current = (Hashtable<String,Object>)current.remove(" PARENT ");
                if (current == null) {
                    throw new KrbException("Unmatched close brace");
D
duke 已提交
606
                }
W
weijun 已提交
607 608 609 610
            } else {
                int pos = line.indexOf('=');
                if (pos < 0) {
                    throw new KrbException("Illegal config content:" + line);
D
duke 已提交
611
                }
W
weijun 已提交
612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640
                String key = line.substring(0, pos).trim();
                String value = trimmed(line.substring(pos+1));
                if (value.equals("{")) {
                    Hashtable<String,Object> subTable;
                    if (current == stanzaTable) {
                        key = key.toLowerCase(Locale.US);
                    }
                    subTable = new Hashtable<>();
                    current.put(key, subTable);
                    // A special entry for its parent. Put whitespaces around,
                    // so will never be confused with a normal key
                    subTable.put(" PARENT ", current);
                    current = subTable;
                } else {
                    Vector<String> values;
                    if (current.containsKey(key)) {
                        Object obj = current.get(key);
                        // If a key first shows as a section and then a value,
                        // this is illegal. However, we haven't really forbid
                        // first value then section, which the final result
                        // is a section.
                        if (!(obj instanceof Vector)) {
                            throw new KrbException("Key " + key
                                    + "used for both value and section");
                        }
                        values = (Vector<String>)current.get(key);
                    } else {
                        values = new Vector<String>();
                        current.put(key, values);
D
duke 已提交
641
                    }
W
weijun 已提交
642
                    values.add(value);
D
duke 已提交
643 644 645
                }
            }
        }
W
weijun 已提交
646 647 648 649
        if (current != stanzaTable) {
            throw new KrbException("Not closed");
        }
        return current;
D
duke 已提交
650 651 652
    }

    /**
653
     * Gets the default Java configuration file name.
654 655
     *
     * If the system property "java.security.krb5.conf" is defined, we'll
656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679
     * use its value, no matter if the file exists or not. Otherwise, we
     * will look at $JAVA_HOME/lib/security directory with "krb5.conf" name,
     * and return it if the file exists.
     *
     * The method returns null if it cannot find a Java config file.
     */
    private String getJavaFileName() {
        String name = getProperty("java.security.krb5.conf");
        if (name == null) {
            name = getProperty("java.home") + File.separator +
                                "lib" + File.separator + "security" +
                                File.separator + "krb5.conf";
            if (!fileExists(name)) {
                name = null;
            }
        }
        if (DEBUG) {
            System.out.println("Java config name: " + name);
        }
        return name;
    }

    /**
     * Gets the default native configuration file name.
680
     *
681 682 683 684
     * Depending on the OS type, the method returns the default native
     * kerberos config file name, which is at windows directory with
     * the name of "krb5.ini" for Windows, /etc/krb5/krb5.conf for Solaris,
     * /etc/krb5.conf otherwise. Mac OSX X has a different file name.
685 686 687 688 689 690
     *
     * Note: When the Terminal Service is started in Windows (from 2003),
     * there are two kinds of Windows directories: A system one (say,
     * C:\Windows), and a user-private one (say, C:\Users\Me\Windows).
     * We will first look for krb5.ini in the user-private one. If not
     * found, try the system one instead.
691 692 693
     *
     * This method will always return a non-null non-empty file name,
     * even if that file does not exist.
D
duke 已提交
694
     */
695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710
    private String getNativeFileName() {
        String name = null;
        String osname = getProperty("os.name");
        if (osname.startsWith("Windows")) {
            try {
                Credentials.ensureLoaded();
            } catch (Exception e) {
                // ignore exceptions
            }
            if (Credentials.alreadyLoaded) {
                String path = getWindowsDirectory(false);
                if (path != null) {
                    if (path.endsWith("\\")) {
                        path = path + "krb5.ini";
                    } else {
                        path = path + "\\krb5.ini";
D
duke 已提交
711
                    }
712 713
                    if (fileExists(path)) {
                        name = path;
714
                    }
715 716 717 718 719 720 721 722 723 724
                }
                if (name == null) {
                    path = getWindowsDirectory(true);
                    if (path != null) {
                        if (path.endsWith("\\")) {
                            path = path + "krb5.ini";
                        } else {
                            path = path + "\\krb5.ini";
                        }
                        name = path;
D
duke 已提交
725 726 727
                    }
                }
            }
728 729 730 731 732 733 734 735 736
            if (name == null) {
                name = "c:\\winnt\\krb5.ini";
            }
        } else if (osname.startsWith("SunOS")) {
            name =  "/etc/krb5/krb5.conf";
        } else if (osname.contains("OS X")) {
            name = findMacosConfigFile();
        } else {
            name =  "/etc/krb5.conf";
D
duke 已提交
737 738
        }
        if (DEBUG) {
739
            System.out.println("Native config name: " + name);
D
duke 已提交
740 741 742 743
        }
        return name;
    }

744 745 746
    private static String getProperty(String property) {
        return java.security.AccessController.doPrivileged(
                new sun.security.action.GetPropertyAction(property));
747 748 749 750 751
    }

    private String findMacosConfigFile() {
        String userHome = getProperty("user.home");
        final String PREF_FILE = "/Library/Preferences/edu.mit.Kerberos";
752
        String userPrefs = userHome + PREF_FILE;
753 754 755 756 757 758 759 760 761

        if (fileExists(userPrefs)) {
            return userPrefs;
        }

        if (fileExists(PREF_FILE)) {
            return PREF_FILE;
        }

762
        return "/etc/krb5.conf";
763 764
    }

765 766
    private static String trimmed(String s) {
        s = s.trim();
W
weijun 已提交
767
        if (s.isEmpty()) return s;
768 769 770 771 772 773
        if (s.charAt(0) == '"' && s.charAt(s.length()-1) == '"' ||
                s.charAt(0) == '\'' && s.charAt(s.length()-1) == '\'') {
            s = s.substring(1, s.length()-1).trim();
        }
        return s;
    }
D
duke 已提交
774 775 776 777 778 779

    /**
     * For testing purpose. This method lists all information being parsed from
     * the configuration file to the hashtable.
     */
    public void listTable() {
W
weijun 已提交
780
        System.out.println(this);
D
duke 已提交
781 782 783
    }

    /**
784 785 786
     * Returns all etypes specified in krb5.conf for the given configName,
     * or all the builtin defaults. This result is always non-empty.
     * If no etypes are found, an exception is thrown.
D
duke 已提交
787
     */
788
    public int[] defaultEtype(String configName) throws KrbException {
D
duke 已提交
789
        String default_enctypes;
790
        default_enctypes = get("libdefaults", configName);
D
duke 已提交
791 792 793 794
        int[] etype;
        if (default_enctypes == null) {
            if (DEBUG) {
                System.out.println("Using builtin default etypes for " +
795
                    configName);
D
duke 已提交
796 797 798
            }
            etype = EType.getBuiltInDefaults();
        } else {
799 800
            String delim = " ";
            StringTokenizer st;
D
duke 已提交
801 802 803 804 805 806 807 808 809 810
            for (int j = 0; j < default_enctypes.length(); j++) {
                if (default_enctypes.substring(j, j + 1).equals(",")) {
                    // only two delimiters are allowed to use
                    // according to Kerberos DCE doc.
                    delim = ",";
                    break;
                }
            }
            st = new StringTokenizer(default_enctypes, delim);
            int len = st.countTokens();
811
            ArrayList<Integer> ls = new ArrayList<>(len);
D
duke 已提交
812 813
            int type;
            for (int i = 0; i < len; i++) {
W
weijun 已提交
814
                type = Config.getType(st.nextToken());
815
                if (type != -1 && EType.isSupported(type)) {
D
duke 已提交
816 817 818
                    ls.add(type);
                }
            }
819
            if (ls.isEmpty()) {
820 821
                throw new KrbException("no supported default etypes for "
                        + configName);
D
duke 已提交
822 823 824 825 826 827 828 829 830
            } else {
                etype = new int[ls.size()];
                for (int i = 0; i < etype.length; i++) {
                    etype[i] = ls.get(i);
                }
            }
        }

        if (DEBUG) {
831
            System.out.print("default etypes for " + configName + ":");
D
duke 已提交
832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850
            for (int i = 0; i < etype.length; i++) {
                System.out.print(" " + etype[i]);
            }
            System.out.println(".");
        }
        return etype;
    }


    /**
     * Get the etype and checksum value for the specified encryption and
     * checksum type.
     *
     */
    /*
     * This method converts the string representation of encryption type and
     * checksum type to int value that can be later used by EType and
     * Checksum classes.
     */
W
weijun 已提交
851
    public static int getType(String input) {
D
duke 已提交
852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916
        int result = -1;
        if (input == null) {
            return result;
        }
        if (input.startsWith("d") || (input.startsWith("D"))) {
            if (input.equalsIgnoreCase("des-cbc-crc")) {
                result = EncryptedData.ETYPE_DES_CBC_CRC;
            } else if (input.equalsIgnoreCase("des-cbc-md5")) {
                result = EncryptedData.ETYPE_DES_CBC_MD5;
            } else if (input.equalsIgnoreCase("des-mac")) {
                result = Checksum.CKSUMTYPE_DES_MAC;
            } else if (input.equalsIgnoreCase("des-mac-k")) {
                result = Checksum.CKSUMTYPE_DES_MAC_K;
            } else if (input.equalsIgnoreCase("des-cbc-md4")) {
                result = EncryptedData.ETYPE_DES_CBC_MD4;
            } else if (input.equalsIgnoreCase("des3-cbc-sha1") ||
                input.equalsIgnoreCase("des3-hmac-sha1") ||
                input.equalsIgnoreCase("des3-cbc-sha1-kd") ||
                input.equalsIgnoreCase("des3-cbc-hmac-sha1-kd")) {
                result = EncryptedData.ETYPE_DES3_CBC_HMAC_SHA1_KD;
            }
        } else if (input.startsWith("a") || (input.startsWith("A"))) {
            // AES
            if (input.equalsIgnoreCase("aes128-cts") ||
                input.equalsIgnoreCase("aes128-cts-hmac-sha1-96")) {
                result = EncryptedData.ETYPE_AES128_CTS_HMAC_SHA1_96;
            } else if (input.equalsIgnoreCase("aes256-cts") ||
                input.equalsIgnoreCase("aes256-cts-hmac-sha1-96")) {
                result = EncryptedData.ETYPE_AES256_CTS_HMAC_SHA1_96;
            // ARCFOUR-HMAC
            } else if (input.equalsIgnoreCase("arcfour-hmac") ||
                   input.equalsIgnoreCase("arcfour-hmac-md5")) {
                result = EncryptedData.ETYPE_ARCFOUR_HMAC;
            }
        // RC4-HMAC
        } else if (input.equalsIgnoreCase("rc4-hmac")) {
            result = EncryptedData.ETYPE_ARCFOUR_HMAC;
        } else if (input.equalsIgnoreCase("CRC32")) {
            result = Checksum.CKSUMTYPE_CRC32;
        } else if (input.startsWith("r") || (input.startsWith("R"))) {
            if (input.equalsIgnoreCase("rsa-md5")) {
                result = Checksum.CKSUMTYPE_RSA_MD5;
            } else if (input.equalsIgnoreCase("rsa-md5-des")) {
                result = Checksum.CKSUMTYPE_RSA_MD5_DES;
            }
        } else if (input.equalsIgnoreCase("hmac-sha1-des3-kd")) {
            result = Checksum.CKSUMTYPE_HMAC_SHA1_DES3_KD;
        } else if (input.equalsIgnoreCase("hmac-sha1-96-aes128")) {
            result = Checksum.CKSUMTYPE_HMAC_SHA1_96_AES128;
        } else if (input.equalsIgnoreCase("hmac-sha1-96-aes256")) {
            result = Checksum.CKSUMTYPE_HMAC_SHA1_96_AES256;
        } else if (input.equalsIgnoreCase("hmac-md5-rc4") ||
                input.equalsIgnoreCase("hmac-md5-arcfour") ||
                input.equalsIgnoreCase("hmac-md5-enc")) {
            result = Checksum.CKSUMTYPE_HMAC_MD5_ARCFOUR;
        } else if (input.equalsIgnoreCase("NULL")) {
            result = EncryptedData.ETYPE_NULL;
        }

        return result;
    }

    /**
     * Resets the default kdc realm.
     * We do not need to synchronize these methods since assignments are atomic
917 918
     *
     * This method was useless. Kept here in case some class still calls it.
D
duke 已提交
919 920 921
     */
    public void resetDefaultRealm(String realm) {
        if (DEBUG) {
922
            System.out.println(">>> Config try resetting default kdc " + realm);
D
duke 已提交
923 924 925 926 927 928 929 930 931 932
        }
    }

    /**
     * Check to use addresses in tickets
     * use addresses if "no_addresses" or "noaddresses" is set to false
     */
    public boolean useAddresses() {
        boolean useAddr = false;
        // use addresses if "no_addresses" is set to false
W
weijun 已提交
933
        String value = get("libdefaults", "no_addresses");
D
duke 已提交
934 935 936
        useAddr = (value != null && value.equalsIgnoreCase("false"));
        if (useAddr == false) {
            // use addresses if "noaddresses" is set to false
W
weijun 已提交
937
            value = get("libdefaults", "noaddresses");
D
duke 已提交
938 939 940 941 942 943 944 945
            useAddr = (value != null && value.equalsIgnoreCase("false"));
        }
        return useAddr;
    }

    /**
     * Check if need to use DNS to locate Kerberos services
     */
W
weijun 已提交
946 947
    private boolean useDNS(String name) {
        String value = get("libdefaults", name);
W
weijun 已提交
948
        if (value == null) {
W
weijun 已提交
949
            value = get("libdefaults", "dns_fallback");
950 951 952 953 954
            if ("false".equalsIgnoreCase(value)) {
                return false;
            } else {
                return true;
            }
W
weijun 已提交
955 956
        } else {
            return value.equalsIgnoreCase("true");
D
duke 已提交
957 958 959 960 961 962
        }
    }

    /**
     * Check if need to use DNS to locate the KDC
     */
W
weijun 已提交
963
    private boolean useDNS_KDC() {
D
duke 已提交
964 965 966 967 968 969
        return useDNS("dns_lookup_kdc");
    }

    /*
     * Check if need to use DNS to locate the Realm
     */
W
weijun 已提交
970
    private boolean useDNS_Realm() {
D
duke 已提交
971 972 973 974 975
        return useDNS("dns_lookup_realm");
    }

    /**
     * Gets default realm.
976 977
     * @throws KrbException where no realm can be located
     * @return the default realm, always non null
D
duke 已提交
978 979
     */
    public String getDefaultRealm() throws KrbException {
980 981 982
        if (defaultRealm != null) {
            return defaultRealm;
        }
983
        Exception cause = null;
W
weijun 已提交
984
        String realm = get("libdefaults", "default_realm");
D
duke 已提交
985 986
        if ((realm == null) && useDNS_Realm()) {
            // use DNS to locate Kerberos realm
987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011
            try {
                realm = getRealmFromDNS();
            } catch (KrbException ke) {
                cause = ke;
            }
        }
        if (realm == null) {
            realm = java.security.AccessController.doPrivileged(
                    new java.security.PrivilegedAction<String>() {
                @Override
                public String run() {
                    String osname = System.getProperty("os.name");
                    if (osname.startsWith("Windows")) {
                        return System.getenv("USERDNSDOMAIN");
                    }
                    return null;
                }
            });
        }
        if (realm == null) {
            KrbException ke = new KrbException("Cannot locate default realm");
            if (cause != null) {
                ke.initCause(cause);
            }
            throw ke;
D
duke 已提交
1012 1013 1014 1015 1016 1017 1018
        }
        return realm;
    }

    /**
     * Returns a list of KDC's with each KDC separated by a space
     *
1019 1020 1021
     * @param realm the realm for which the KDC list is desired
     * @throws KrbException if there's no way to find KDC for the realm
     * @return the list of KDCs separated by a space, always non null
D
duke 已提交
1022 1023 1024 1025 1026
     */
    public String getKDCList(String realm) throws KrbException {
        if (realm == null) {
            realm = getDefaultRealm();
        }
1027 1028 1029
        if (realm.equalsIgnoreCase(defaultRealm)) {
            return defaultKDC;
        }
1030
        Exception cause = null;
W
weijun 已提交
1031
        String kdcs = getAll("realms", realm, "kdc");
D
duke 已提交
1032 1033
        if ((kdcs == null) && useDNS_KDC()) {
            // use DNS to locate KDC
1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058
            try {
                kdcs = getKDCFromDNS(realm);
            } catch (KrbException ke) {
                cause = ke;
            }
        }
        if (kdcs == null) {
            kdcs = java.security.AccessController.doPrivileged(
                    new java.security.PrivilegedAction<String>() {
                @Override
                public String run() {
                    String osname = System.getProperty("os.name");
                    if (osname.startsWith("Windows")) {
                        String logonServer = System.getenv("LOGONSERVER");
                        if (logonServer != null
                                && logonServer.startsWith("\\\\")) {
                            logonServer = logonServer.substring(2);
                        }
                        return logonServer;
                    }
                    return null;
                }
            });
        }
        if (kdcs == null) {
1059 1060 1061
            if (defaultKDC != null) {
                return defaultKDC;
            }
1062 1063 1064 1065 1066
            KrbException ke = new KrbException("Cannot locate KDC");
            if (cause != null) {
                ke.initCause(cause);
            }
            throw ke;
D
duke 已提交
1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080
        }
        return kdcs;
    }

    /**
     * Locate Kerberos realm using DNS
     *
     * @return the Kerberos realm
     */
    private String getRealmFromDNS() throws KrbException {
        // use DNS to locate Kerberos realm
        String realm = null;
        String hostName = null;
        try {
1081
            hostName = InetAddress.getLocalHost().getCanonicalHostName();
D
duke 已提交
1082 1083 1084 1085 1086 1087 1088 1089
        } catch (UnknownHostException e) {
            KrbException ke = new KrbException(Krb5.KRB_ERR_GENERIC,
                "Unable to locate Kerberos realm: " + e.getMessage());
            ke.initCause(e);
            throw (ke);
        }
        // get the domain realm mapping from the configuration
        String mapRealm = PrincipalName.mapHostToRealm(hostName);
1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116
        if (mapRealm == null) {
            // No match. Try search and/or domain in /etc/resolv.conf
            List<String> srchlist = ResolverConfiguration.open().searchlist();
            for (String domain: srchlist) {
                realm = checkRealm(domain);
                if (realm != null) {
                    break;
                }
            }
        } else {
            realm = checkRealm(mapRealm);
        }
        if (realm == null) {
            throw new KrbException(Krb5.KRB_ERR_GENERIC,
                                "Unable to locate Kerberos realm");
        }
        return realm;
    }

    /**
     * Check if the provided realm is the correct realm
     * @return the realm if correct, or null otherwise
     */
    private static String checkRealm(String mapRealm) {
        if (DEBUG) {
            System.out.println("getRealmFromDNS: trying " + mapRealm);
        }
D
duke 已提交
1117 1118 1119 1120 1121 1122 1123 1124
        String[] records = null;
        String newRealm = mapRealm;
        while ((records == null) && (newRealm != null)) {
            // locate DNS TXT record
            records = KrbServiceLocator.getKerberosService(newRealm);
            newRealm = Realm.parseRealmComponent(newRealm);
            // if no DNS TXT records found, try again using sub-realm
        }
1125 1126 1127 1128 1129
        if (records != null) {
            for (int i = 0; i < records.length; i++) {
                if (records[i].equalsIgnoreCase(mapRealm)) {
                    return records[i];
                }
D
duke 已提交
1130 1131
            }
        }
1132
        return null;
D
duke 已提交
1133 1134 1135 1136 1137 1138 1139 1140 1141 1142
    }

    /**
     * Locate KDC using DNS
     *
     * @param realm the realm for which the master KDC is desired
     * @return the KDC
     */
    private String getKDCFromDNS(String realm) throws KrbException {
        // use DNS to locate KDC
1143
        String kdcs = "";
D
duke 已提交
1144 1145
        String[] srvs = null;
        // locate DNS SRV record using UDP
1146 1147 1148 1149
        if (DEBUG) {
            System.out.println("getKDCFromDNS using UDP");
        }
        srvs = KrbServiceLocator.getKerberosService(realm, "_udp");
D
duke 已提交
1150 1151
        if (srvs == null) {
            // locate DNS SRV record using TCP
1152
            if (DEBUG) {
1153
                System.out.println("getKDCFromDNS using TCP");
1154 1155
            }
            srvs = KrbServiceLocator.getKerberosService(realm, "_tcp");
D
duke 已提交
1156 1157 1158 1159 1160 1161
        }
        if (srvs == null) {
            // no DNS SRV records
            throw new KrbException(Krb5.KRB_ERR_GENERIC,
                "Unable to locate KDC for realm " + realm);
        }
1162 1163 1164
        if (srvs.length == 0) {
            return null;
        }
D
duke 已提交
1165
        for (int i = 0; i < srvs.length; i++) {
1166 1167 1168 1169 1170
            kdcs += srvs[i].trim() + " ";
        }
        kdcs = kdcs.trim();
        if (kdcs.equals("")) {
            return null;
D
duke 已提交
1171 1172 1173 1174
        }
        return kdcs;
    }

1175 1176 1177 1178 1179
    private boolean fileExists(String name) {
        return java.security.AccessController.doPrivileged(
                                new FileExistsAction(name));
    }

D
duke 已提交
1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193
    static class FileExistsAction
        implements java.security.PrivilegedAction<Boolean> {

        private String fileName;

        public FileExistsAction(String fileName) {
            this.fileName = fileName;
        }

        public Boolean run() {
            return new File(fileName).exists();
        }
    }

1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206
    // Shows the content of the Config object for debug purpose.
    //
    // {
    //      libdefaults = {
    //          default_realm = R
    //      }
    //      realms = {
    //          R = {
    //              kdc = [k1,k2]
    //          }
    //      }
    // }

1207 1208 1209
    @Override
    public String toString() {
        StringBuffer sb = new StringBuffer();
1210
        toStringInternal("", stanzaTable, sb);
1211 1212
        return sb.toString();
    }
1213
    private static void toStringInternal(String prefix, Object obj,
1214 1215
            StringBuffer sb) {
        if (obj instanceof String) {
1216 1217
            // A string value, just print it
            sb.append(obj).append('\n');
1218
        } else if (obj instanceof Hashtable) {
1219
            // A table, start a new sub-section...
1220
            Hashtable<?, ?> tab = (Hashtable<?, ?>)obj;
1221
            sb.append("{\n");
1222
            for (Object o: tab.keySet()) {
1223 1224 1225 1226
                // ...indent, print "key = ", and
                sb.append(prefix).append("    ").append(o).append(" = ");
                // ...go recursively into value
                toStringInternal(prefix + "    ", tab.get(o), sb);
1227
            }
1228
            sb.append(prefix).append("}\n");
1229
        } else if (obj instanceof Vector) {
1230
            // A vector of strings, print them inside [ and ]
1231
            Vector<?> v = (Vector<?>)obj;
1232 1233
            sb.append("[");
            boolean first = true;
1234
            for (Object o: v.toArray()) {
1235 1236 1237
                if (!first) sb.append(",");
                sb.append(o);
                first = false;
1238
            }
1239
            sb.append("]\n");
1240 1241
        }
    }
D
duke 已提交
1242
}