remctl Java Implementation

OVERVIEW

  This directory contains a remctl implementation written in Java.  Both a
  client and a server are included, and the implementation supports
  version two of the remctl protocol.  Both client and server are written
  natively in Java and are entirely independent of the C implementation.

  This implementation is not as mature or as well-tested as the C
  implementation.  Any feedback and bug reports are gratefully accepted.

REQUIREMENTS

  This implementation works with the Sun Java JDK 1.4.2, 5, and 6.  It
  will not build with gcj; it could be ported, but wouldn't be useful
  until gcj has com.sun.security.auth.module.Krb5LoginModule or an
  equivalent.

  You can use either the provided simple Makefile or ant to build the JAR
  file.  This source tree will also build in Eclipse and includes an
  Eclipse .project and .classpath file.

  To use 256-bit AES keys, you will need to get the "Java Cryptography
  Extension (ECE) Unlimited Strength Jurisdiction Policy Files 6"
  (filename jce_policy-6.zip), which is available (at least to US
  residents) from <http://java.sun.com/javase/downloads/index.jsp>.

BUILDING

  If you have ant available, it's the easiest way to build the JAR file.
  Running ant dist will build the JAR file and put it in dist/lib.  You
  may have to set ANT_HOME and JAVA_HOME to point ant at the appropriate
  directories.

  If you do not have ant, you can use the provided Makefile, which will
  create the JAR file in the current directory.  If your JDK isn't at
  /usr/lib/jvm/java-6-sun, either edit the Makefile to change JAVA_HOME
  and then run make, set the JAVA_HOME variable on the command line with:

      make JAVA_HOME=/path/to/jdk

  or set JAVA_HOME in the environment.

  However you do the build, create a k5.conf file by copying your
  /etc/krb5.conf file and then adding these lines to the [libdefaults]
  section:

      default_tgs_enctypes = des3-hmac-sha1 des-cbc-crc des-cbc-md5
      default_tkt_enctypes = des3-hmac-sha1 des-cbc-crc des-cbc-md5
      permitted_enctypes = des3-hmac-sha1 des-cbc-crc des-cbc-md5

  MIT Kerberos and Heimdal do not need this configuration and it is wrong
  for them, but the built-in list for Sun Java is limited and it will
  break if it encounters encryption types that it doesn't understand.  The
  sample k5.conf in this directory can be used, but change the default
  realm.

  You can remove the DES enctypes if your realm doesn't support DES.  If
  you are using Java 6, you can add aes128-cts to the beginning of each
  list.  If you have the jce_policy-6.zip file installed, you can also add
  aes256-cts to the beginning of each line.

RUNNING

  You can now run the client from the JAR file:

      java -Djava.security.krb5.conf=k5.conf \
          -Djava.security.auth.login.config=j3.conf -jar remctl-*.jar \
          <host> <command> <subcommand> [<parameter> ...]

  This connects to the remctld on <host> and sends the command <type>
  <service> <parameter>.  If you're using ant, the JAR file will be in
  dist/lib instead.  You can also run the client from the class files:

      java -Djava.security.krb5.conf=k5.conf \
          -Djava.security.auth.login.config=j3.conf \
          -cp build:. org.eyrie.eagle.remctl.RemctlClient \
          <host> <command> <subcommand> [<parameter> ...]

  Also look at t5.java for an example of how to use the class in a Java
  program.

  To run the server, create a keytab that the server will use for
  authentication and revise bcsKeytab.conf to match (you will need to
  change the principal at least).  Then, start the server with:

      java -Djavax.security.auth.useSubjectCredsOnly=false \
          -Djava.security.auth.login.config=bcsKeytab.conf -cp build:. \
          t7 4373 <principal>

  This will start the server defined in t7.java, which just returns
  information about what command it received.  4373 is the port to listen
  to (4373 is the default value for remctl).  Replace <principal> for the
  principal you created a keytab for.

  To run this from Eclipse, select from the Run, Run..., "java
  application", make an instance for the selected Main Class.  Under
  Arguments, set VM arguments to be those above for "java", and set the
  program arguments to be everything past the jar file or main class.

CREATING A DISTRIBUTION

  The java directory of the remctl distribution is not structured like a
  conventional Java distribution.  However, you can generate an
  independent source distribution that looks much more like a standard
  Java distribution using ant.  Optionally first run ant dist to build the
  JAR file and then run ant tar to generate the distribution (which will
  then be found in dist).  This generated distribution will be structured
  like an Apache Jakarta project:

      dist/lib          The built JAR file with the version in its name
      doc               This documentation and the sample configuration
      src               The JAR file source

  The running instructions above will be slightly different if you use
  this distribution, since the configuration files will be in doc instead
  of at the top level and the test Java files will be in bin.

HISTORY

  This Java remctl implementation was written by Marcus Watts, based
  somewhat on the original remctl Java implementation by Anton Ushakov.
  The build system and this documentation is based on the build system and
  documentation provided by Marcus.