diff options
Diffstat (limited to 'prov/src/main/java/org/spongycastle/pqc/jcajce/provider/mceliece/BCMcEliecePublicKey.java')
| -rw-r--r-- | prov/src/main/java/org/spongycastle/pqc/jcajce/provider/mceliece/BCMcEliecePublicKey.java | 231 |
1 files changed, 231 insertions, 0 deletions
diff --git a/prov/src/main/java/org/spongycastle/pqc/jcajce/provider/mceliece/BCMcEliecePublicKey.java b/prov/src/main/java/org/spongycastle/pqc/jcajce/provider/mceliece/BCMcEliecePublicKey.java new file mode 100644 index 00000000..25c6fd14 --- /dev/null +++ b/prov/src/main/java/org/spongycastle/pqc/jcajce/provider/mceliece/BCMcEliecePublicKey.java @@ -0,0 +1,231 @@ +package org.spongycastle.pqc.jcajce.provider.mceliece; + +import java.io.IOException; +import java.security.PublicKey; + +import org.spongycastle.asn1.ASN1ObjectIdentifier; +import org.spongycastle.asn1.ASN1Primitive; +import org.spongycastle.asn1.DERNull; +import org.spongycastle.asn1.x509.AlgorithmIdentifier; +import org.spongycastle.asn1.x509.SubjectPublicKeyInfo; +import org.spongycastle.crypto.CipherParameters; +import org.spongycastle.pqc.asn1.McEliecePublicKey; +import org.spongycastle.pqc.crypto.mceliece.McElieceKeyPairGenerator; +import org.spongycastle.pqc.crypto.mceliece.McElieceParameters; +import org.spongycastle.pqc.crypto.mceliece.McEliecePublicKeyParameters; +import org.spongycastle.pqc.jcajce.spec.McEliecePublicKeySpec; +import org.spongycastle.pqc.math.linearalgebra.GF2Matrix; + +/** + * This class implements a McEliece public key and is usually instantiated by + * the {@link McElieceKeyPairGenerator} or {@link McElieceKeyFactorySpi}. + */ +public class BCMcEliecePublicKey + implements CipherParameters, PublicKey +{ + + /** + * + */ + private static final long serialVersionUID = 1L; + + // the OID of the algorithm + private String oid; + + /** + * the length of the code + */ + private int n; + + /** + * the error correction capability of the code + */ + private int t; + + /** + * the generator matrix + */ + private GF2Matrix g; + + private McElieceParameters McElieceParams; + + /** + * Constructor (used by the {@link McElieceKeyPairGenerator}). + * + * @param oid + * @param n the length of the code + * @param t the error correction capability of the code + * @param g the generator matrix + */ + public BCMcEliecePublicKey(String oid, int n, int t, GF2Matrix g) + { + this.oid = oid; + this.n = n; + this.t = t; + this.g = g; + } + + /** + * Constructor (used by the {@link McElieceKeyFactorySpi}). + * + * @param keySpec a {@link McEliecePublicKeySpec} + */ + public BCMcEliecePublicKey(McEliecePublicKeySpec keySpec) + { + this(keySpec.getOIDString(), keySpec.getN(), keySpec.getT(), keySpec.getG()); + } + + public BCMcEliecePublicKey(McEliecePublicKeyParameters params) + { + this(params.getOIDString(), params.getN(), params.getT(), params.getG()); + this.McElieceParams = params.getParameters(); + } + + /** + * Return the name of the algorithm. + * + * @return "McEliece" + */ + public String getAlgorithm() + { + return "McEliece"; + } + + /** + * @return the length of the code + */ + public int getN() + { + return n; + } + + /** + * @return the dimension of the code + */ + public int getK() + { + return g.getNumRows(); + } + + /** + * @return the error correction capability of the code + */ + public int getT() + { + return t; + } + + /** + * @return the generator matrix + */ + public GF2Matrix getG() + { + return g; + } + + /** + * @return a human readable form of the key + */ + public String toString() + { + String result = "McEliecePublicKey:\n"; + result += " length of the code : " + n + "\n"; + result += " error correction capability: " + t + "\n"; + result += " generator matrix : " + g.toString(); + return result; + } + + /** + * Compare this key with another object. + * + * @param other the other object + * @return the result of the comparison + */ + public boolean equals(Object other) + { + if (!(other instanceof BCMcEliecePublicKey)) + { + return false; + } + BCMcEliecePublicKey otherKey = (BCMcEliecePublicKey)other; + + return (n == otherKey.n) && (t == otherKey.t) && g.equals(otherKey.g); + } + + /** + * @return the hash code of this key + */ + public int hashCode() + { + return n + t + g.hashCode(); + } + + + /** + * @return the OID of the algorithm + */ + public String getOIDString() + { + return oid; + } + + /** + * @return the OID to encode in the SubjectPublicKeyInfo structure + */ + protected ASN1ObjectIdentifier getOID() + { + return new ASN1ObjectIdentifier(McElieceKeyFactorySpi.OID); + } + + /** + * @return the algorithm parameters to encode in the SubjectPublicKeyInfo + * structure + */ + protected ASN1Primitive getAlgParams() + { + return null; // FIXME: needed at all? + } + + + /** + * Return the keyData to encode in the SubjectPublicKeyInfo structure. + * <p/> + * The ASN.1 definition of the key structure is + * <p/> + * <pre> + * McEliecePublicKey ::= SEQUENCE { + * n Integer -- length of the code + * t Integer -- error correcting capability + * matrixG OctetString -- generator matrix as octet string + * } + * </pre> + * + * @return the keyData to encode in the SubjectPublicKeyInfo structure + */ + public byte[] getEncoded() + { + McEliecePublicKey key = new McEliecePublicKey(new ASN1ObjectIdentifier(oid), n, t, g); + AlgorithmIdentifier algorithmIdentifier = new AlgorithmIdentifier(this.getOID(), DERNull.INSTANCE); + + try + { + SubjectPublicKeyInfo subjectPublicKeyInfo = new SubjectPublicKeyInfo(algorithmIdentifier, key); + + return subjectPublicKeyInfo.getEncoded(); + } + catch (IOException e) + { + return null; + } + } + + public String getFormat() + { + return null; + } + + public McElieceParameters getMcElieceParameters() + { + return McElieceParams; + } +} |