passwordfile.java

linux下建立JAVA虚拟机的源码KAFFE

    final String index = (String) fields.get(CONFIG_FIELD);
    fields.put(VERIFIERS_FIELD, newVerifiers(user, salt, passwd, index));
    entries.put(user, fields);
    savePasswd();
  }

  public synchronized void savePasswd() throws IOException
  {
    final FileOutputStream f1 = new FileOutputStream(passwdFile);
    final FileOutputStream f2 = new FileOutputStream(passwd2File);
    PrintWriter pw1 = null;
    PrintWriter pw2 = null;
    try
      {
        pw1 = new PrintWriter(f1, true);
        pw2 = new PrintWriter(f2, true);
        this.writePasswd(pw1, pw2);
      }
    finally
      {
        if (pw1 != null)
          {
            try
              {
                pw1.flush();
              }
            finally
              {
                pw1.close();
              }
          }
        if (pw2 != null)
          {
            try
              {
                pw2.flush();
              }
            finally
              {
                pw2.close();
              }
          }
        try
          {
            f1.close();
          }
        catch (IOException ignored)
          {
          }
        try
          {
            f2.close();
          }
        catch (IOException ignored)
          {
          }
      }
    lastmodPasswdFile = passwdFile.lastModified();
    lastmodPasswd2File = passwd2File.lastModified();
  }

  /**
   * <p>Returns the triplet: verifier, salt and configuration file index, of a
   * designated user, and a designated message digest algorithm name, as an
   * array of strings.</p>
   *
   * @param user the username.
   * @param mdName the canonical name of the SRP's message digest algorithm.
   * @return a string array containing, in this order, the BASE-64 encodings of
   * the verifier, the salt and the index in the password configuration file of
   * the MPIs N and g of the designated user.
   */
  public synchronized String[] lookup(final String user, final String mdName)
      throws IOException
  {
    checkCurrent();
    if (!entries.containsKey(user))
      {
        throw new NoSuchUserException(user);
      }
    final HashMap fields = (HashMap) entries.get(user);
    final HashMap verifiers = (HashMap) fields.get(VERIFIERS_FIELD);
    final String salt = (String) fields.get(SALT_FIELD);
    final String index = (String) fields.get(CONFIG_FIELD);
    final String verifier = (String) verifiers.get(nameToID(mdName));
    return new String[] { verifier, salt, index };
  }

  // Other instance methods --------------------------------------------------

  private synchronized void readOrCreateConf() throws IOException
  {
    configurations.clear();
    final FileInputStream fis;
    configFile = new File(confName);
    try
      {
        fis = new FileInputStream(configFile);
        readConf(fis);
      }
    catch (FileNotFoundException x)
      { // create a default one
        final String g = Util.toBase64(Util.trim(new BigInteger("2")));
        String index, N;
        for (int i = 0; i < Nsrp.length; i++)
          {
            index = String.valueOf(i + 1);
            N = Util.toBase64(Util.trim(Nsrp[i]));
            configurations.put(index, new String[] { N, g });
          }
        FileOutputStream f0 = null;
        PrintWriter pw0 = null;
        try
          {
            f0 = new FileOutputStream(configFile);
            pw0 = new PrintWriter(f0, true);
            this.writeConf(pw0);
          }
        finally
          {
            if (pw0 != null)
              {
                pw0.close();
              }
            else if (f0 != null)
              {
                f0.close();
              }
          }
      }
  }

  private void readConf(final InputStream in) throws IOException
  {
    final BufferedReader din = new BufferedReader(new InputStreamReader(in));
    String line, index, N, g;
    StringTokenizer st;
    while ((line = din.readLine()) != null)
      {
        st = new StringTokenizer(line, ":");
        try
          {
            index = st.nextToken();
            N = st.nextToken();
            g = st.nextToken();
          }
        catch (NoSuchElementException x)
          {
            throw new IOException("SRP password configuration file corrupt");
          }
        configurations.put(index, new String[] { N, g });
      }
  }

  private void writeConf(final PrintWriter pw)
  {
    String ndx;
    String[] mpi;
    StringBuffer sb;
    for (Iterator it = configurations.keySet().iterator(); it.hasNext();)
      {
        ndx = (String) it.next();
        mpi = (String[]) configurations.get(ndx);
        sb = new StringBuffer(ndx).append(":").append(mpi[0]).append(":").append(
                                                                                 mpi[1]);
        pw.println(sb.toString());
      }
  }

  /**
   * <p>Compute the new verifiers for the designated username and password.</p>
   *
   * <p><b>IMPORTANT:</b> This method computes the verifiers as described in
   * RFC-2945, which differs from the description given on the web page for
   * SRP-6.</p>
   *
   * @param user the user's name.
   * @param s the user's salt.
   * @param password the user's password
   * @param index the index of the &lt;N, g> pair to use for this user.
   * @return a {@link java.util.Map} of user verifiers.
   * @throws UnsupportedEncodingException if the US-ASCII decoder is not
   * available on this platform.
   */
  private HashMap newVerifiers(final String user, final byte[] s,
                               final String password, final String index)
      throws UnsupportedEncodingException
  {
    // to ensure inter-operability with non-java tools
    final String[] mpi = (String[]) configurations.get(index);
    final BigInteger N = new BigInteger(1, Util.fromBase64(mpi[0]));
    final BigInteger g = new BigInteger(1, Util.fromBase64(mpi[1]));

    final HashMap result = new HashMap(srps.size());
    BigInteger x, v;
    SRP srp;
    for (int i = 0; i < srps.size(); i++)
      {
        final String digestID = String.valueOf(i);
        srp = (SRP) srps.get(digestID);
        x = new BigInteger(1, srp.computeX(s, user, password));
        v = g.modPow(x, N);
        final String verifier = Util.toBase64(v.toByteArray());

        result.put(digestID, verifier);
      }
    return result;
  }

  private synchronized void update() throws IOException
  {
    entries.clear();

    FileInputStream fis;
    passwdFile = new File(pwName);
    lastmodPasswdFile = passwdFile.lastModified();
    try
      {
        fis = new FileInputStream(passwdFile);
        readPasswd(fis);
      }
    catch (FileNotFoundException ignored)
      {
      }
    passwd2File = new File(pw2Name);
    lastmodPasswd2File = passwd2File.lastModified();
    try
      {
        fis = new FileInputStream(passwd2File);
        readPasswd2(fis);
      }
    catch (FileNotFoundException ignored)
      {
      }
  }

  private void checkCurrent() throws IOException
  {
    if (passwdFile.lastModified() > lastmodPasswdFile
        || passwd2File.lastModified() > lastmodPasswd2File)
      {
        update();
      }
  }

  private void readPasswd(final InputStream in) throws IOException
  {
    final BufferedReader din = new BufferedReader(new InputStreamReader(in));
    String line, user, verifier, salt, index;
    StringTokenizer st;
    while ((line = din.readLine()) != null)
      {
        st = new StringTokenizer(line, ":");
        try
          {
            user = st.nextToken();
            verifier = st.nextToken();
            salt = st.nextToken();
            index = st.nextToken();
          }
        catch (NoSuchElementException x)
          {
            throw new IOException("SRP base password file corrupt");
          }

        final HashMap verifiers = new HashMap(6);
        verifiers.put("0", verifier);

        final HashMap fields = new HashMap(4);
        fields.put(USER_FIELD, user);
        fields.put(VERIFIERS_FIELD, verifiers);
        fields.put(SALT_FIELD, salt);
        fields.put(CONFIG_FIELD, index);

        entries.put(user, fields);
      }
  }

  private void readPasswd2(final InputStream in) throws IOException
  {
    final BufferedReader din = new BufferedReader(new InputStreamReader(in));
    String line, digestID, user, verifier;
    StringTokenizer st;
    HashMap fields, verifiers;
    while ((line = din.readLine()) != null)
      {
        st = new StringTokenizer(line, ":");
        try
          {
            digestID = st.nextToken();
            user = st.nextToken();
            verifier = st.nextToken();
          }
        catch (NoSuchElementException x)
          {
            throw new IOException("SRP extended password file corrupt");
          }

        fields = (HashMap) entries.get(user);
        if (fields != null)
          {
            verifiers = (HashMap) fields.get(VERIFIERS_FIELD);
            verifiers.put(digestID, verifier);
          }
      }
  }

  private void writePasswd(final PrintWriter pw1, final PrintWriter pw2)
      throws IOException
  {
    String user, digestID;
    HashMap fields, verifiers;
    StringBuffer sb1, sb2;
    Iterator j;
    final Iterator i = entries.keySet().iterator();
    while (i.hasNext())
      {
        user = (String) i.next();
        fields = (HashMap) entries.get(user);
        if (!user.equals(fields.get(USER_FIELD)))
          {
            throw new IOException("Inconsistent SRP password data");
          }
        verifiers = (HashMap) fields.get(VERIFIERS_FIELD);
        sb1 = new StringBuffer().append(user).append(":").append(
                                                                 (String) verifiers.get("0")).append(
                                                                                                     ":").append(
                                                                                                                 (String) fields.get(SALT_FIELD)).append(
                                                                                                                                                         ":").append(
                                                                                                                                                                     (String) fields.get(CONFIG_FIELD));
        pw1.println(sb1.toString());
        // write extended information
        j = verifiers.keySet().iterator();
        while (j.hasNext())
          {
            digestID = (String) j.next();
            if (!"0".equals(digestID))
              {
                // #0 is the default digest, already present in tpasswd!
                sb2 = new StringBuffer().append(digestID).append(":").append(
                                                                             user).append(
                                                                                          ":").append(
                                                                                                      (String) verifiers.get(digestID));
                pw2.println(sb2.toString());
              }
          }
      }
  }
}