freebsd-dev/crypto/openssl/README.ENGINE

  ENGINE
  ======

  With OpenSSL 0.9.6, a new component has been added to support external 
  crypto devices, for example accelerator cards.  The component is called
  ENGINE, and has still a pretty experimental status and almost no
  documentation.  It's designed to be fairly easily extensible by the
  calling programs.

  There's currently built-in support for the following crypto devices:

      o CryptoSwift
      o Compaq Atalla
      o nCipher CHIL

  A number of things are still needed and are being worked on:

      o An openssl utility command to handle or at least check available
        engines.
      o A better way of handling the methods that are handled by the
        engines.
      o Documentation!

  What already exists is fairly stable as far as it has been tested, but
  the test base has been a bit small most of the time.

  Because of this experimental status and what's lacking, the ENGINE
  component is not yet part of the default OpenSSL distribution.  However,
  we have made a separate kit for those who want to try this out, to be
  found in the same places as the default OpenSSL distribution, but with
  "-engine-" being part of the kit file name.  For example, version 0.9.6
  is distributed in the following two files:

      openssl-0.9.6.tar.gz
      openssl-engine-0.9.6.tar.gz

  NOTES
  =====

  openssl-engine-0.9.6.tar.gz does not depend on openssl-0.9.6.tar, you do
  not need to download both.

  openssl-engine-0.9.6.tar.gz is usable even if you don't have an external
  crypto device.  The internal OpenSSL functions are contained in the
  engine "openssl", and will be used by default.

  No external crypto device is chosen unless you say so.  You have actively
  tell the openssl utility commands to use it through a new command line
  switch called "-engine".  And if you want to use the ENGINE library to
  do something similar, you must also explicitly choose an external crypto
  device, or the built-in crypto routines will be used, just as in the
  default OpenSSL distribution.


  PROBLEMS
  ========

  It seems like the ENGINE part doesn't work too well with CryptoSwift on
  Win32.  A quick test done right before the release showed that trying
  "openssl speed -engine cswift" generated errors.  If the DSO gets enabled,
  an attempt is made to write at memory address 0x00000002.