Added BIKE KEM algorithm

Added getEncapsulationLength() method to EncapsulatedSecretExtractor.

Author: dghgit

core/src/main/java/org/bouncycastle/asn1/bc/BCObjectIdentifiers.java

@@ -358,4 +358,20 @@ public interface BCObjectIdentifiers
     ASN1ObjectIdentifier sntrup953 = pqc_kem_sntruprime.branch("4");
     ASN1ObjectIdentifier sntrup1013 = pqc_kem_sntruprime.branch("5");
     ASN1ObjectIdentifier sntrup1277 = pqc_kem_sntruprime.branch("6");
+    
+    /**
+     * BIKE
+     **/
+    ASN1ObjectIdentifier pqc_kem_bike = bc_kem.branch("8");
+    ASN1ObjectIdentifier bike128 = pqc_kem_bike.branch("1");
+    ASN1ObjectIdentifier bike192 = pqc_kem_bike.branch("2");
+    ASN1ObjectIdentifier bike256 = pqc_kem_bike.branch("3");
+
+    /**
+     * HQC
+     **/
+    ASN1ObjectIdentifier pqc_kem_hqc = bc_kem.branch("9");
+    ASN1ObjectIdentifier hqc128 = pqc_kem_hqc.branch("1");
+    ASN1ObjectIdentifier hqc192 = pqc_kem_hqc.branch("2");
+    ASN1ObjectIdentifier hqc256 = pqc_kem_hqc.branch("3");
 }

core/src/main/java/org/bouncycastle/crypto/EncapsulatedSecretExtractor.java

@@ -8,4 +8,11 @@ public interface EncapsulatedSecretExtractor
      * @param encapsulation the encapsulated secret.
      */
     byte[] extractSecret(byte[] encapsulation);
+
+    /**
+     * Return the length in bytes of the encapsulation.
+     *
+     * @return length in bytes of an encapsulation for this parameter set.
+     */
+    int getEncapsulationLength();
 }

core/src/main/java/org/bouncycastle/crypto/kems/ECIESKEMExtractor.java

@@ -116,4 +116,9 @@ public byte[] extractSecret(byte[] encapsulation)
 
         return ECIESKEMGenerator.deriveKey(SingleHashMode, kdf, keyLen, encapsulation, PEH);
     }
+
+    public int getEncapsulationLength()
+    {
+        return (decKey.getParameters().getCurve().getFieldSize() / 8) * 2 + 1;
+    }
 }

core/src/main/java/org/bouncycastle/crypto/kems/RSAKEMExtractor.java

@@ -58,4 +58,9 @@ public byte[] extractSecret(byte[] encapsulation)
 
         return RSAKEMGenerator.generateKey(kdf, n, r, keyLen);
     }
+
+    public int getEncapsulationLength()
+    {
+        return (privKey.getModulus().bitLength() + 7) / 8;
+    }
 }