======================================================================
README for the scyther-proof security protocol verification tool
======================================================================
Author: Simon Meier <simon.meier@inf.ethz.ch>
Creation Date: 13/05/2011
1. Introduction
===============
Every distribution of the scyther-proof tool contains a copy of the
Isabelle/HOL theories formalizing its verification theory and a copy of the
protocol models that were verified using scyther-proof. In particular, these
examples include models for all of our repaired versions of the protocols
from the ISO/IEC-9798 authentication standard. (In the source distribution
of scyther-proof they can be found at 'data/examples/iso9798'.)
In the following sections, we give step by step instructions to get the
whole system working and we explain the usage of our tools and provide
further information (e.g., building documentation).
2. Installation instructions
============================
2.1 Installing scyther-proof
----------------------------
You need a working Haskell environment that provides GHC 7 and the 'cabal
install' tool. The simplest way to get such an environment is to download and
install the Haskell Platform package for your OS.
http://hackage.haskell.org/platform/
Then call
cabal install
in the root directory of this source code package. This will use the
Haskell's deployment tool 'cabal-install' to download all missing libraries
from Hackage, the central Haskell library repository and install the
'scyther-proof' executable in the default installation location of
cabal-install. The installation location is printed at the end of the build
process.
Call
scyther-proof
without any arguments to get an overview of the arguments supported and the
paths to the examples and the Isabelle/HOL theories.
3.2 Installing the Isabelle/HOL theories
----------------------------------------
Download and install full Isabelle2009-1 according to the installation
instructions at
http://isabelle.in.tum.de/website-Isabelle2009-1/download_x86-linux.html
The first time you call 'scyther-proof' with the '--isabelle' flag it will
build the logic image of the Isabelle/HOL theories formalizing the security
protocol verification theory underlying scyther-proof.
For enabling interactive processing of theory files based using our
extensions to Isabelle's ISAR proof language use one of the following two
variants.
Variant a: Brute Force
----------------------
Overwrite the standard Emacs keywords file
$ISABELLE_HOME/etc/isar-keywords.el
with the Emacs keywords file provided with the ESPL distribution.
$SCYTHER_PROOF_HOME/isabelle/src/isar-keywords.el
This is needed in order to make the new ISAR keywords "role",
"protocol", "sources", and "prefix_close" available in the Emacs
frontend.
Variant b: Elegance
-------------------
A more elegant way is to copy the keywords file provided with our
distribution to
$ISABELLE_HOME/etc/isar-keywords-ESPL.el
and start Isabelle using the -k switch as follows.
isabelle emacs -k ESPL <your-theory-file.thy>
3. Usage
========
3.1 scyther-proof
------------
Usage Example
-------------
You can now execute the 'scyther-proof' binary without any arguments to get a
list of the available flags. A simple example usage is (assuming
'scyther-proof' is in the PATH).
scyther-proof $EXAMPLE_DIR/classic/NS_Public.spthy --shortest
This will parse the NSL protocol modeled in the 'nsl.spthy' file and output
all specified security properties together with the proof with the fewest
number of chain rule applications to stdout.
In order to generate an Isabelle proof script two additional options need to
be added
scyther-proof $EXAMPLE_DIR/classic/NS_Public.spthy --shortest --output=nsl_cert.thy --ASCII
The first one specifies the output file and the second one instructs
scyther-proof to use Isabelle's ASCII notation as the output format.
To build the source code documentation you can use the call
cabal configure; cabal haddock
which will use cabal-install and Haskell's source code documentation tool
'haddock' to build the source code documentation. The location of this
documentation is again output on the command line.
3.2 The Isabelle/HOL theories
-----------------------------
In the directory output by scyther-proof, load the Tutorial on interactive
proof construction using the following commands
cd <theory-dir-output-by-scytherproof>/src
isabelle emacs Tutorial.thy
or if you've chosen the elegant variant
isabelle emacs -k ESPL Tutorial.thy
Note that in many case the easiest way to start with constructing
machine-checked proofs interactively is to use a proof script generated by
scyther-proof.
***
* Happy Proving :-)
*
* In case of questions do not hesistate to contact me at
* simon.meier@inf.ethz.ch
***
