@prefix : <#> .
@prefix log: <http://www.w3.org/2000/10/swap/log#> .
@prefix crypto: <http://www.w3.org/2000/10/swap/crypto#> .
@prefix string: <http://www.w3.org/2000/10/swap/string#> .

this log:forAll :x , :y , :z , :q .

# The rules

# Get my file contents, and hash it

{ <MyFile.txt> log:content [ crypto:md5 :x ] } 
   log:implies { <MyFile.txt> :md5 :x } .

# Get my key from a local key file

# { <MyKeyPair.rsa> log:content :x } log:implies { :Bob :keyPair :x } .
# { <MyPubKey.rsa> log:content :x } log:implies { :Bob :pubKey :x } .
{ :x crypto:keyLength "1024" } log:implies { :Bob :keyPair :x } .

{ :Bob :keyPair :x . :x crypto:publicKey :y } 
   log:implies { :Bob :pubKey :y } .

# Sign the hash of my document with my key

{ <MyFile.txt> :md5 :x . :Bob :keyPair :y . 
  (:x :y) crypto:sign :z } log:implies { :z a :Signature } .

# Verify the signature... once against the file, and once against some junk

{ :Bob :pubKey :x . <MyFile.txt> :md5 :y . :z a :Signature . 
  (:x :y :z) crypto:verifyBoolean :q } log:implies { :q :shouldBeEqualTo "1" } .

{ :Bob :pubKey :x . :z a :Signature . 
  (:x "garbage" :z) crypto:verifyBoolean :q } 
   log:implies { :q :shouldBeEqualTo "0" } .

{ :Bob :pubKey :x . <MyFile.txt> :md5 :y . :z a :Signature . 
  :x crypto:verify (:y :z) } log:implies { :Test a :Pass } .
{ :Bob :pubKey :x . :z a :Signature . 
  :x crypto:verify ("garbage" :z) } log:implies { :Test a :Fail } .

{ :Bob :keyPair [ crypto:keyLength :x ] } log:implies 
   { :Bob :keyPairLength :x } .

# For purging

log:implies a log:Chaff .
log:forAll a log:Chaff .