001/*
002 * Copyright 2008-2018 Ping Identity Corporation
003 * All Rights Reserved.
004 */
005/*
006 * Copyright (C) 2008-2018 Ping Identity Corporation
007 *
008 * This program is free software; you can redistribute it and/or modify
009 * it under the terms of the GNU General Public License (GPLv2 only)
010 * or the terms of the GNU Lesser General Public License (LGPLv2.1 only)
011 * as published by the Free Software Foundation.
012 *
013 * This program is distributed in the hope that it will be useful,
014 * but WITHOUT ANY WARRANTY; without even the implied warranty of
015 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
016 * GNU General Public License for more details.
017 *
018 * You should have received a copy of the GNU General Public License
019 * along with this program; if not, see <http://www.gnu.org/licenses>.
020 */
021package com.unboundid.util.ssl;
022
023
024import java.io.BufferedReader;
025import java.io.BufferedWriter;
026import java.io.File;
027import java.io.FileReader;
028import java.io.FileWriter;
029import java.io.InputStream;
030import java.io.InputStreamReader;
031import java.io.IOException;
032import java.io.PrintStream;
033import java.nio.file.Files;
034import java.security.cert.Certificate;
035import java.security.cert.CertificateException;
036import java.security.cert.X509Certificate;
037import java.util.ArrayList;
038import java.util.Collection;
039import java.util.Collections;
040import java.util.List;
041import java.util.concurrent.ConcurrentHashMap;
042import javax.net.ssl.X509TrustManager;
043
044import com.unboundid.util.Debug;
045import com.unboundid.util.NotMutable;
046import com.unboundid.util.ObjectPair;
047import com.unboundid.util.ThreadSafety;
048import com.unboundid.util.ThreadSafetyLevel;
049import com.unboundid.util.ssl.cert.CertException;
050
051import static com.unboundid.util.Debug.*;
052import static com.unboundid.util.StaticUtils.*;
053import static com.unboundid.util.ssl.SSLMessages.*;
054
055
056
057/**
058 * This class provides an SSL trust manager that will interactively prompt the
059 * user to determine whether to trust any certificate that is presented to it.
060 * It provides the ability to cache information about certificates that had been
061 * previously trusted so that the user is not prompted about the same
062 * certificate repeatedly, and it can be configured to store trusted
063 * certificates in a file so that the trust information can be persisted.
064 */
065@NotMutable()
066@ThreadSafety(level=ThreadSafetyLevel.COMPLETELY_THREADSAFE)
067public final class PromptTrustManager
068       implements X509TrustManager
069{
070  /**
071   * A pre-allocated empty certificate array.
072   */
073  private static final X509Certificate[] NO_CERTIFICATES =
074       new X509Certificate[0];
075
076
077
078  // Indicates whether to examine the validity dates for the certificate in
079  // addition to whether the certificate has been previously trusted.
080  private final boolean examineValidityDates;
081
082  // The set of previously-accepted certificates.  The certificates will be
083  // mapped from an all-lowercase hexadecimal string representation of the
084  // certificate signature to a flag that indicates whether the certificate has
085  // already been manually trusted even if it is outside of the validity window.
086  private final ConcurrentHashMap<String,Boolean> acceptedCerts;
087
088  // The input stream from which the user input will be read.
089  private final InputStream in;
090
091  // A list of the addresses that the client is expected to use to connect to
092  // one of the target servers.
093  private final List<String> expectedAddresses;
094
095  // The print stream that will be used to display the prompt.
096  private final PrintStream out;
097
098  // The path to the file to which the set of accepted certificates should be
099  // persisted.
100  private final String acceptedCertsFile;
101
102
103
104  /**
105   * Creates a new instance of this prompt trust manager.  It will cache trust
106   * information in memory but not on disk.
107   */
108  public PromptTrustManager()
109  {
110    this(null, true, null, null);
111  }
112
113
114
115  /**
116   * Creates a new instance of this prompt trust manager.  It may optionally
117   * cache trust information on disk.
118   *
119   * @param  acceptedCertsFile  The path to a file in which the certificates
120   *                            that have been previously accepted will be
121   *                            cached.  It may be {@code null} if the cache
122   *                            should only be maintained in memory.
123   */
124  public PromptTrustManager(final String acceptedCertsFile)
125  {
126    this(acceptedCertsFile, true, null, null);
127  }
128
129
130
131  /**
132   * Creates a new instance of this prompt trust manager.  It may optionally
133   * cache trust information on disk, and may also be configured to examine or
134   * ignore validity dates.
135   *
136   * @param  acceptedCertsFile     The path to a file in which the certificates
137   *                               that have been previously accepted will be
138   *                               cached.  It may be {@code null} if the cache
139   *                               should only be maintained in memory.
140   * @param  examineValidityDates  Indicates whether to reject certificates if
141   *                               the current time is outside the validity
142   *                               window for the certificate.
143   * @param  in                    The input stream that will be used to read
144   *                               input from the user.  If this is {@code null}
145   *                               then {@code System.in} will be used.
146   * @param  out                   The print stream that will be used to display
147   *                               the prompt to the user.  If this is
148   *                               {@code null} then System.out will be used.
149   */
150  public PromptTrustManager(final String acceptedCertsFile,
151                            final boolean examineValidityDates,
152                            final InputStream in, final PrintStream out)
153  {
154    this(acceptedCertsFile, examineValidityDates,
155         Collections.<String>emptyList(), in, out);
156  }
157
158
159
160  /**
161   * Creates a new instance of this prompt trust manager.  It may optionally
162   * cache trust information on disk, and may also be configured to examine or
163   * ignore validity dates.
164   *
165   * @param  acceptedCertsFile     The path to a file in which the certificates
166   *                               that have been previously accepted will be
167   *                               cached.  It may be {@code null} if the cache
168   *                               should only be maintained in memory.
169   * @param  examineValidityDates  Indicates whether to reject certificates if
170   *                               the current time is outside the validity
171   *                               window for the certificate.
172   * @param  expectedAddress       An optional address that the client is
173   *                               expected to use to connect to the target
174   *                               server.  This may be {@code null} if no
175   *                               expected address is available, if this trust
176   *                               manager is only expected to be used to
177   *                               validate client certificates, or if no server
178   *                               address validation should be performed.  If a
179   *                               non-{@code null} value is provided, then the
180   *                               trust manager may issue a warning if the
181   *                               certificate does not contain that address.
182   * @param  in                    The input stream that will be used to read
183   *                               input from the user.  If this is {@code null}
184   *                               then {@code System.in} will be used.
185   * @param  out                   The print stream that will be used to display
186   *                               the prompt to the user.  If this is
187   *                               {@code null} then System.out will be used.
188   */
189  public PromptTrustManager(final String acceptedCertsFile,
190                            final boolean examineValidityDates,
191                            final String expectedAddress, final InputStream in,
192                            final PrintStream out)
193  {
194    this(acceptedCertsFile, examineValidityDates,
195         (expectedAddress == null)
196              ? Collections.<String>emptyList()
197              : Collections.singletonList(expectedAddress),
198         in, out);
199  }
200
201
202
203  /**
204   * Creates a new instance of this prompt trust manager.  It may optionally
205   * cache trust information on disk, and may also be configured to examine or
206   * ignore validity dates.
207   *
208   * @param  acceptedCertsFile     The path to a file in which the certificates
209   *                               that have been previously accepted will be
210   *                               cached.  It may be {@code null} if the cache
211   *                               should only be maintained in memory.
212   * @param  examineValidityDates  Indicates whether to reject certificates if
213   *                               the current time is outside the validity
214   *                               window for the certificate.
215   * @param  expectedAddresses     An optional collection of the addresses that
216   *                               the client is expected to use to connect to
217   *                               one of the target servers.  This may be
218   *                               {@code null} or empty if no expected
219   *                               addresses are available, if this trust
220   *                               manager is only expected to be used to
221   *                               validate client certificates, or if no server
222   *                               address validation should be performed.  If a
223   *                               non-empty collection is provided, then the
224   *                               trust manager may issue a warning if the
225   *                               certificate does not contain any of these
226   *                               addresses.
227   * @param  in                    The input stream that will be used to read
228   *                               input from the user.  If this is {@code null}
229   *                               then {@code System.in} will be used.
230   * @param  out                   The print stream that will be used to display
231   *                               the prompt to the user.  If this is
232   *                               {@code null} then System.out will be used.
233   */
234  public PromptTrustManager(final String acceptedCertsFile,
235                            final boolean examineValidityDates,
236                            final Collection<String> expectedAddresses,
237                            final InputStream in, final PrintStream out)
238  {
239    this.acceptedCertsFile    = acceptedCertsFile;
240    this.examineValidityDates = examineValidityDates;
241
242    if (expectedAddresses == null)
243    {
244      this.expectedAddresses = Collections.emptyList();
245    }
246    else
247    {
248      this.expectedAddresses =
249           Collections.unmodifiableList(new ArrayList<>(expectedAddresses));
250    }
251
252    if (in == null)
253    {
254      this.in = System.in;
255    }
256    else
257    {
258      this.in = in;
259    }
260
261    if (out == null)
262    {
263      this.out = System.out;
264    }
265    else
266    {
267      this.out = out;
268    }
269
270    acceptedCerts = new ConcurrentHashMap<String,Boolean>();
271
272    if (acceptedCertsFile != null)
273    {
274      BufferedReader r = null;
275      try
276      {
277        final File f = new File(acceptedCertsFile);
278        if (f.exists())
279        {
280          r = new BufferedReader(new FileReader(f));
281          while (true)
282          {
283            final String line = r.readLine();
284            if (line == null)
285            {
286              break;
287            }
288            acceptedCerts.put(line, false);
289          }
290        }
291      }
292      catch (final Exception e)
293      {
294        debugException(e);
295      }
296      finally
297      {
298        if (r != null)
299        {
300          try
301          {
302            r.close();
303          }
304          catch (final Exception e)
305          {
306            debugException(e);
307          }
308        }
309      }
310    }
311  }
312
313
314
315  /**
316   * Writes an updated copy of the trusted certificate cache to disk.
317   *
318   * @throws  IOException  If a problem occurs.
319   */
320  private void writeCacheFile()
321          throws IOException
322  {
323    final File tempFile = new File(acceptedCertsFile + ".new");
324
325    BufferedWriter w = null;
326    try
327    {
328      w = new BufferedWriter(new FileWriter(tempFile));
329
330      for (final String certBytes : acceptedCerts.keySet())
331      {
332        w.write(certBytes);
333        w.newLine();
334      }
335    }
336    finally
337    {
338      if (w != null)
339      {
340        w.close();
341      }
342    }
343
344    final File cacheFile = new File(acceptedCertsFile);
345    if (cacheFile.exists())
346    {
347      final File oldFile = new File(acceptedCertsFile + ".previous");
348      if (oldFile.exists())
349      {
350        Files.delete(oldFile.toPath());
351      }
352
353      Files.move(cacheFile.toPath(), oldFile.toPath());
354    }
355
356    Files.move(tempFile.toPath(), cacheFile.toPath());
357  }
358
359
360
361  /**
362   * Indicates whether this trust manager would interactively prompt the user
363   * about whether to trust the provided certificate chain.
364   *
365   * @param  chain  The chain of certificates for which to make the
366   *                determination.
367   *
368   * @return  {@code true} if this trust manger would interactively prompt the
369   *          user about whether to trust the certificate chain, or
370   *          {@code false} if not (e.g., because the certificate is already
371   *          known to be trusted).
372   */
373  public synchronized boolean wouldPrompt(final X509Certificate[] chain)
374  {
375    try
376    {
377      final String cacheKey = getCacheKey(chain[0]);
378      return PromptTrustManagerProcessor.shouldPrompt(cacheKey,
379           convertChain(chain), false, examineValidityDates, acceptedCerts,
380           null).getFirst();
381    }
382    catch (final Exception e)
383    {
384      Debug.debugException(e);
385      return false;
386    }
387  }
388
389
390
391  /**
392   * Performs the necessary validity check for the provided certificate array.
393   *
394   * @param  chain       The chain of certificates for which to make the
395   *                     determination.
396   * @param  serverCert  Indicates whether the certificate was presented as a
397   *                     server certificate or as a client certificate.
398   *
399   * @throws  CertificateException  If the provided certificate chain should not
400   *                                be trusted.
401   */
402  private synchronized void checkCertificateChain(final X509Certificate[] chain,
403                                                  final boolean serverCert)
404          throws CertificateException
405  {
406    final com.unboundid.util.ssl.cert.X509Certificate[] convertedChain =
407         convertChain(chain);
408
409    final String cacheKey = getCacheKey(chain[0]);
410    final ObjectPair<Boolean,List<String>> shouldPromptResult =
411         PromptTrustManagerProcessor.shouldPrompt(cacheKey, convertedChain,
412              serverCert, examineValidityDates, acceptedCerts,
413              expectedAddresses);
414
415    if (! shouldPromptResult.getFirst())
416    {
417      return;
418    }
419
420    if (serverCert)
421    {
422      out.println(INFO_PROMPT_SERVER_HEADING.get());
423    }
424    else
425    {
426      out.println(INFO_PROMPT_CLIENT_HEADING.get());
427    }
428
429    out.println();
430    out.println("     " +
431         INFO_PROMPT_SUBJECT.get(convertedChain[0].getSubjectDN()));
432    out.println("     " +
433         INFO_PROMPT_VALID_FROM.get(PromptTrustManagerProcessor.formatDate(
434              convertedChain[0].getNotBeforeDate())));
435    out.println("     " +
436         INFO_PROMPT_VALID_TO.get(PromptTrustManagerProcessor.formatDate(
437              convertedChain[0].getNotAfterDate())));
438
439    try
440    {
441      final byte[] sha1Fingerprint = convertedChain[0].getSHA1Fingerprint();
442      final StringBuilder buffer = new StringBuilder();
443      toHex(sha1Fingerprint, ":", buffer);
444      out.println("     " + INFO_PROMPT_SHA1_FINGERPRINT.get(buffer));
445    }
446    catch (final Exception e)
447    {
448      Debug.debugException(e);
449    }
450    try
451    {
452      final byte[] sha256Fingerprint = convertedChain[0].getSHA256Fingerprint();
453      final StringBuilder buffer = new StringBuilder();
454      toHex(sha256Fingerprint, ":", buffer);
455      out.println("     " + INFO_PROMPT_SHA256_FINGERPRINT.get(buffer));
456    }
457    catch (final Exception e)
458    {
459      Debug.debugException(e);
460    }
461
462
463    for (int i=1; i < chain.length; i++)
464    {
465      out.println("     -");
466      out.println("     " +
467           INFO_PROMPT_ISSUER_SUBJECT.get(i, convertedChain[i].getSubjectDN()));
468      out.println("     " +
469           INFO_PROMPT_VALID_FROM.get(PromptTrustManagerProcessor.formatDate(
470                convertedChain[i].getNotBeforeDate())));
471      out.println("     " +
472           INFO_PROMPT_VALID_TO.get(PromptTrustManagerProcessor.formatDate(
473                convertedChain[i].getNotAfterDate())));
474
475      try
476      {
477        final byte[] sha1Fingerprint = convertedChain[i].getSHA1Fingerprint();
478        final StringBuilder buffer = new StringBuilder();
479        toHex(sha1Fingerprint, ":", buffer);
480        out.println("     " + INFO_PROMPT_SHA1_FINGERPRINT.get(buffer));
481      }
482      catch (final Exception e)
483      {
484        Debug.debugException(e);
485      }
486      try
487      {
488        final byte[] sha256Fingerprint =
489             convertedChain[i].getSHA256Fingerprint();
490        final StringBuilder buffer = new StringBuilder();
491        toHex(sha256Fingerprint, ":", buffer);
492        out.println("     " + INFO_PROMPT_SHA256_FINGERPRINT.get(buffer));
493      }
494      catch (final Exception e)
495      {
496        Debug.debugException(e);
497      }
498    }
499
500    for (final String warningMessage : shouldPromptResult.getSecond())
501    {
502      out.println();
503      for (final String line :
504           wrapLine(warningMessage, (TERMINAL_WIDTH_COLUMNS - 1)))
505      {
506        out.println(line);
507      }
508    }
509
510    final BufferedReader reader = new BufferedReader(new InputStreamReader(in));
511    while (true)
512    {
513      try
514      {
515        out.println();
516        out.print(INFO_PROMPT_MESSAGE.get() + ' ');
517        out.flush();
518        final String line = reader.readLine();
519        if (line == null)
520        {
521          // The input stream has been closed, so we can't prompt for trust,
522          // and should assume it is not trusted.
523          throw new CertificateException(
524               ERR_CERTIFICATE_REJECTED_BY_END_OF_STREAM.get(
525                    SSLUtil.certificateToString(chain[0])));
526        }
527        else if (line.equalsIgnoreCase("y") || line.equalsIgnoreCase("yes"))
528        {
529          // The certificate should be considered trusted.
530          break;
531        }
532        else if (line.equalsIgnoreCase("n") || line.equalsIgnoreCase("no"))
533        {
534          // The certificate should not be trusted.
535          throw new CertificateException(
536               ERR_CERTIFICATE_REJECTED_BY_USER.get(
537                    SSLUtil.certificateToString(chain[0])));
538        }
539      }
540      catch (final CertificateException ce)
541      {
542        throw ce;
543      }
544      catch (final Exception e)
545      {
546        debugException(e);
547      }
548    }
549
550    boolean isOutsideValidityWindow = false;
551    for (final com.unboundid.util.ssl.cert.X509Certificate c : convertedChain)
552    {
553      if (! c.isWithinValidityWindow())
554      {
555        isOutsideValidityWindow = true;
556        break;
557      }
558    }
559
560    acceptedCerts.put(cacheKey, isOutsideValidityWindow);
561
562    if (acceptedCertsFile != null)
563    {
564      try
565      {
566        writeCacheFile();
567      }
568      catch (final Exception e)
569      {
570        debugException(e);
571      }
572    }
573  }
574
575
576
577  /**
578   * Indicate whether to prompt about certificates contained in the cache if the
579   * current time is outside the validity window for the certificate.
580   *
581   * @return  {@code true} if the certificate validity time should be examined
582   *          for cached certificates and the user should be prompted if they
583   *          are expired or not yet valid, or {@code false} if cached
584   *          certificates should be accepted even outside of the validity
585   *          window.
586   */
587  public boolean examineValidityDates()
588  {
589    return examineValidityDates;
590  }
591
592
593
594  /**
595   * Retrieves a list of the addresses that the client is expected to use to
596   * communicate with the server, if available.
597   *
598   * @return  A list of the addresses that the client is expected to use to
599   *          communicate with the server, or an empty list if this is not
600   *          available or applicable.
601   */
602  public List<String> getExpectedAddresses()
603  {
604    return expectedAddresses;
605  }
606
607
608
609  /**
610   * Checks to determine whether the provided client certificate chain should be
611   * trusted.
612   *
613   * @param  chain     The client certificate chain for which to make the
614   *                   determination.
615   * @param  authType  The authentication type based on the client certificate.
616   *
617   * @throws  CertificateException  If the provided client certificate chain
618   *                                should not be trusted.
619   */
620  @Override()
621  public void checkClientTrusted(final X509Certificate[] chain,
622                                 final String authType)
623         throws CertificateException
624  {
625    checkCertificateChain(chain, false);
626  }
627
628
629
630  /**
631   * Checks to determine whether the provided server certificate chain should be
632   * trusted.
633   *
634   * @param  chain     The server certificate chain for which to make the
635   *                   determination.
636   * @param  authType  The key exchange algorithm used.
637   *
638   * @throws  CertificateException  If the provided server certificate chain
639   *                                should not be trusted.
640   */
641  @Override()
642  public void checkServerTrusted(final X509Certificate[] chain,
643                                 final String authType)
644         throws CertificateException
645  {
646    checkCertificateChain(chain, true);
647  }
648
649
650
651  /**
652   * Retrieves the accepted issuer certificates for this trust manager.  This
653   * will always return an empty array.
654   *
655   * @return  The accepted issuer certificates for this trust manager.
656   */
657  @Override()
658  public X509Certificate[] getAcceptedIssuers()
659  {
660    return NO_CERTIFICATES;
661  }
662
663
664
665  /**
666   * Retrieves the cache key used to identify the provided certificate in the
667   * map of accepted certificates.
668   *
669   * @param  certificate  The certificate for which to get the cache key.
670   *
671   * @return  The generated cache key.
672   */
673  static String getCacheKey(final Certificate certificate)
674  {
675    final X509Certificate x509Certificate = (X509Certificate) certificate;
676    return toLowerCase(toHex(x509Certificate.getSignature()));
677  }
678
679
680
681  /**
682   * Converts the provided certificate chain from Java's representation of
683   * X.509 certificates to the LDAP SDK's version.
684   *
685   * @param  chain  The chain to be converted.
686   *
687   * @return  The converted certificate chain.
688   *
689   * @throws  CertificateException  If a problem occurs while performing the
690   *                                conversion.
691   */
692  static com.unboundid.util.ssl.cert.X509Certificate[]
693             convertChain(final Certificate[] chain)
694         throws CertificateException
695  {
696    final com.unboundid.util.ssl.cert.X509Certificate[] convertedChain =
697         new com.unboundid.util.ssl.cert.X509Certificate[chain.length];
698    for (int i=0; i < chain.length; i++)
699    {
700      try
701      {
702        convertedChain[i] = new com.unboundid.util.ssl.cert.X509Certificate(
703             chain[i].getEncoded());
704      }
705      catch (final CertException ce)
706      {
707        Debug.debugException(ce);
708        throw new CertificateException(ce.getMessage(), ce);
709      }
710    }
711
712    return convertedChain;
713  }
714}