cryptlib is distributed under a dual license that allows free, open-source use
under a GPL-compatible license and closed-source use under a standard
commercial license.  The GPL-compatible license (a.k.a. the Sleepycat license)
is given below.

  Copyright 1992-2026 Peter Gutmann. All rights reserved.

  Redistribution and use in source and binary forms, with or without
  modification, are permitted provided that the following conditions are met:

  1. Redistributions of source code must retain the above copyright notice, this
     list of conditions and the following disclaimer.

  2. Redistributions in binary form must reproduce the above copyright notice,
     this list of conditions and the following disclaimer in the documentation
     and/or other materials provided with the distribution.

  3. Redistributions in any form must be accompanied by information on how to
     obtain complete source code for the cryptlib software and any accompanying
     software that uses the cryptlib software.  The source code must either be
     included in the distribution or be available for no more than the cost of
     distribution, and must be freely redistributable under reasonable
     conditions.  For an executable file, complete source code means the source
     code for all modules it contains or uses.  It does not include source code
     for modules or files that typically accompany the major components of the
     operating system on which the executable file runs.

  THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
  INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT, ARE DISCLAIMED.  IN NO
  EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
  OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
  OF SUCH DAMAGE.

Note that decoupling the software from the user, for example by running in a
SaaS configuration, does not exempt you from these requirements.

If you're unable to comply with the above license then the following,
alternate usage conditions apply:

  Any large-scale commercial use of cryptlib requires a license.  "Large-scale
  commercial use" means any revenue-generating purpose such as use for
  company-internal purposes, or use of cryptlib in an application or product,
  with a total gross revenue of over US$5,000.  This allows cryptlib to be
  used in freeware and shareware applications, for evaluation and research
  purposes, and for non-revenue-generating or personal use without charge.  In
  addition the author reserves the right to grant free licenses for commercial
  use in special cases (for example where there is a general benefit to the
  public), contact the author for details if you think you qualify.
