add sections LIMITATIONS, AUTHOR and COPYRIGHT to the docs

README.rst

@@ -164,11 +164,30 @@ against versions through 5.0.0.
 
 Perl 5 is required for the build.
 
+LIMITATIONS
+===========
+
+The VMOD allocates memory for BLOBs in Varnish workspace.  If its
+methods or functions fail, as indicated by "out of space" messages in
+the Varnish log (with the ``VCL_Error`` tag), then you will need to
+increase the varnishd parameters ``workspace_client`` and/or
+``workspace_backend``.
+
 INSTALLATION
 ============
 
 See `INSTALL.rst <INSTALL.rst>`_ in the source repository.
 
+AUTHOR
+======
+
+* Geoffrey Simmons <geoff@uplex.de>
+
+UPLEX Nils Goroll Systemoptimierung
+
+Cryptographic code is adapted from librhash by Aleksey Kravchenko,
+which is in the public domain (see `LICENSE <LICENSE>`_).
+
 CONTRIBUTING
 ============
 
@@ -184,3 +203,14 @@ SEE ALSO
 * source repository: https://code.uplex.de/uplex-varnish/libvmod-blobdigest
 * VMOD blobcode: https://code.uplex.de/uplex-varnish/libvmod-blobcode
 * VMOD blob: https://code.uplex.de/uplex-varnish/libvmod-blob
+* RHash:
+  * https://github.com/rhash/RHash
+  * http://rhash.anz.ru/
+
+COPYRIGHT
+=========
+
+This document is licensed under the same conditions as the
+libvmod-blobcode project. See `LICENSE <LICENSE>`_ for details.
+
+* Copyright (c) 2016 UPLEX Nils Goroll Systemoptimierung

src/vmod_blobdigest.vcc

@@ -121,11 +121,30 @@ against versions through 5.0.0.
 
 Perl 5 is required for the build.
 
+LIMITATIONS
+===========
+
+The VMOD allocates memory for BLOBs in Varnish workspace.  If its
+methods or functions fail, as indicated by "out of space" messages in
+the Varnish log (with the ``VCL_Error`` tag), then you will need to
+increase the varnishd parameters ``workspace_client`` and/or
+``workspace_backend``.
+
 INSTALLATION
 ============
 
 See `INSTALL.rst <INSTALL.rst>`_ in the source repository.
 
+AUTHOR
+======
+
+* Geoffrey Simmons <geoff@uplex.de>
+
+UPLEX Nils Goroll Systemoptimierung
+
+Cryptographic code is adapted from librhash by Aleksey Kravchenko,
+which is in the public domain (see `LICENSE <LICENSE>`_).
+
 CONTRIBUTING
 ============
 
@@ -141,3 +160,14 @@ SEE ALSO
 * source repository: https://code.uplex.de/uplex-varnish/libvmod-blobdigest
 * VMOD blobcode: https://code.uplex.de/uplex-varnish/libvmod-blobcode
 * VMOD blob: https://code.uplex.de/uplex-varnish/libvmod-blob
+* RHash:
+  * https://github.com/rhash/RHash
+  * http://rhash.anz.ru/
+
+COPYRIGHT
+=========
+
+This document is licensed under the same conditions as the
+libvmod-blobcode project. See `LICENSE <LICENSE>`_ for details.
+
+* Copyright (c) 2016 UPLEX Nils Goroll Systemoptimierung