de.uni_koblenz.aggrimm.icp.crypto.sign.algorithm.algorithm

Class SignatureAlgorithmCarroll2003

java.lang.Object

de.uni_koblenz.aggrimm.icp.crypto.sign.algorithm.algorithm.SignatureAlgorithmCarroll2003

All Implemented Interfaces:

SignatureAlgorithmInterface

public class SignatureAlgorithmCarroll2003
extends Object
implements SignatureAlgorithmInterface

Signature Algorithm "Carroll2003" Ontology Name: carroll-2003 Based on: Carroll, J.J.: Signing RDF graphs. In: ISWC 2003, Springer (2003) 369-384

Author:

Peter Schauß

Constructor Summary

Constructors

Constructor and Description
SignatureAlgorithmCarroll2003()

Method Summary

Modifier and Type	Method and Description
void	addC14NPrefix(GraphCollection gc) Adds c14n prefix to the graph collection (reduces output size)
void	assemble(GraphCollection gc, String signatureGraphName) Assembles a GraphCollection (add signature(s) and a signature graph).
void	canonicalize(GraphCollection gc) Canonicalizes a GraphCollection for a unique representation (commonly blank node removal/labeling and sorting).
String	getName() Gets the name of the signature algorithm (used for identification of the algorithm when signing/verifying)
void	hash(GraphCollection gc, String digestAlgo) Calculates the hash value of a GraphCollection and safes it in its SignatureData.
BigInteger	hashTriples(BigInteger hash, ArrayList<Triple> triples, MessageDigest d) Hash a vector of triples
void	nondeterministicPreCanonicalization(NamedGraph g) Performs nondeterministic pre-canonicalization Use multiple one-step deterministic labeling passes Steps (some may be skipped depending on blank nodes): 1) substituteBlankNodes & oneStepDeterministicLabelling 2) remove all triples with c14n:true predicate 3) substituteBlankNodes & oneStepDeterministicLabelling 4) Add new triples with c14n:true predicate for hard to label blank nodes 5) substituteBlankNodes & oneStepDeterministicLabelling Comments "(Step A)" to "(Step F)" in code below refer to the algorithm description of Carroll
void	postCanonicalize(GraphCollection gc) Executes extra steps after the actual canonicalization of a GraphCollection
void	postHash(GraphCollection gc) Executes extra steps after the actual hash calculation of a GraphCollection
void	sign(GraphCollection gc, Key privateKey, String verificationCertificate) Signs GraphCollection (calculate signature(s) using a certificate/key and the hash value(s)).
boolean	verify(GraphCollection gc, Key publicKey) Verifies a signed graph collection using a public key Involves canonicalization and hashing of the graph collection and a cryptographic signature check

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SignatureAlgorithmCarroll2003

public SignatureAlgorithmCarroll2003()

Method Detail

canonicalize

public void canonicalize(GraphCollection gc)
                  throws Exception

Description copied from interface: SignatureAlgorithmInterface

Canonicalizes a GraphCollection for a unique representation (commonly blank node removal/labeling and sorting). Must set SignatureData.canonicalizationMethod of SignatureData.

Specified by:

canonicalize in interface SignatureAlgorithmInterface

Parameters:

gc - graphCollection which is canonicalized

Throws:

Exception

nondeterministicPreCanonicalization

public void nondeterministicPreCanonicalization(NamedGraph g)
                                         throws Exception

Performs nondeterministic pre-canonicalization Use multiple one-step deterministic labeling passes Steps (some may be skipped depending on blank nodes): 1) substituteBlankNodes & oneStepDeterministicLabelling 2) remove all triples with c14n:true predicate 3) substituteBlankNodes & oneStepDeterministicLabelling 4) Add new triples with c14n:true predicate for hard to label blank nodes 5) substituteBlankNodes & oneStepDeterministicLabelling Comments "(Step A)" to "(Step F)" in code below refer to the algorithm description of Carroll

Parameters:

g - NamedGraph which will be canonicalized

Throws:

Exception

addC14NPrefix

public void addC14NPrefix(GraphCollection gc)

Adds c14n prefix to the graph collection (reduces output size)

Parameters:

gc - GraphCollection to which the C14N prefix will be added

postCanonicalize

public void postCanonicalize(GraphCollection gc)

Description copied from interface: SignatureAlgorithmInterface

Executes extra steps after the actual canonicalization of a GraphCollection

Specified by:

postCanonicalize in interface SignatureAlgorithmInterface

Parameters:

gc - graphCollection which is canonicalized

hash

public void hash(GraphCollection gc,
                 String digestAlgo)
          throws Exception

Description copied from interface: SignatureAlgorithmInterface

Calculates the hash value of a GraphCollection and safes it in its SignatureData. Must set SignatureData.graphDigestMethod and SignatureData.serializationMethod of SignatureData.

Specified by:

hash in interface SignatureAlgorithmInterface

Parameters:

gc - graphCollection which is hashed

digestAlgo - string specifying a digest algorithm

Throws:

Exception

hashTriples

public BigInteger hashTriples(BigInteger hash,
                              ArrayList<Triple> triples,
                              MessageDigest d)
                       throws Exception

Hash a vector of triples

Parameters:

hash - hash to start from as byte array

triples - triples which will be hashed

d - used digest method for hashing

Returns:

resulting hash as byte array

Throws:

Exception

postHash

public void postHash(GraphCollection gc)

Description copied from interface: SignatureAlgorithmInterface

Executes extra steps after the actual hash calculation of a GraphCollection

Specified by:

postHash in interface SignatureAlgorithmInterface

Parameters:

gc - graphCollection which is hashed

sign

public void sign(GraphCollection gc,
                 Key privateKey,
                 String verificationCertificate)
          throws Exception

Description copied from interface: SignatureAlgorithmInterface

Signs GraphCollection (calculate signature(s) using a certificate/key and the hash value(s)). Must set SignatureData.signatureMethod of SignatureData.

Specified by:

sign in interface SignatureAlgorithmInterface

Parameters:

gc - graphCollection which is signed

privateKey - key used to calculate the signature

verificationCertificate - string specifying the certificate which should be used for verification

Throws:

Exception

assemble

public void assemble(GraphCollection gc,
                     String signatureGraphName)
              throws Exception

Description copied from interface: SignatureAlgorithmInterface

Assembles a GraphCollection (add signature(s) and a signature graph).

Specified by:

assemble in interface SignatureAlgorithmInterface

Parameters:

gc - graphCollection which is assembled

signatureGraphName - string name for the signature graph

Throws:

Exception

verify

public boolean verify(GraphCollection gc,
                      Key publicKey)
               throws Exception

Description copied from interface: SignatureAlgorithmInterface

Verifies a signed graph collection using a public key Involves canonicalization and hashing of the graph collection and a cryptographic signature check

Specified by:

verify in interface SignatureAlgorithmInterface

Parameters:

gc - graphCollection which will be verified

publicKey - key for the cryptographic signature check

Returns:

boolean true if verification succeeded, false otherwise

Throws:

Exception

getName

public String getName()

Description copied from interface: SignatureAlgorithmInterface

Gets the name of the signature algorithm (used for identification of the algorithm when signing/verifying)

Specified by:

getName in interface SignatureAlgorithmInterface

Returns:

string name of the algorithm