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diff --git a/core/src/main/java/org/spongycastle/pqc/crypto/mceliece/McElieceCCA2Primitives.java b/core/src/main/java/org/spongycastle/pqc/crypto/mceliece/McElieceCCA2Primitives.java
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+++ b/core/src/main/java/org/spongycastle/pqc/crypto/mceliece/McElieceCCA2Primitives.java
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+package org.spongycastle.pqc.crypto.mceliece;
+
+import org.spongycastle.pqc.math.linearalgebra.GF2Matrix;
+import org.spongycastle.pqc.math.linearalgebra.GF2Vector;
+import org.spongycastle.pqc.math.linearalgebra.GF2mField;
+import org.spongycastle.pqc.math.linearalgebra.GoppaCode;
+import org.spongycastle.pqc.math.linearalgebra.Permutation;
+import org.spongycastle.pqc.math.linearalgebra.PolynomialGF2mSmallM;
+import org.spongycastle.pqc.math.linearalgebra.Vector;
+
+/**
+ * Core operations for the CCA-secure variants of McEliece.
+ */
+public final class McElieceCCA2Primitives
+{
+
+    /**
+     * Default constructor (private).
+     */
+    private McElieceCCA2Primitives()
+    {
+    }
+
+    /**
+     * The McEliece encryption primitive.
+     *
+     * @param pubKey the public key
+     * @param m      the message vector
+     * @param z      the error vector
+     * @return <tt>m*G + z</tt>
+     */
+
+
+    public static GF2Vector encryptionPrimitive(McElieceCCA2PublicKeyParameters pubKey,
+                                                GF2Vector m, GF2Vector z)
+    {
+
+        GF2Matrix matrixG = pubKey.getMatrixG();
+        Vector mG = matrixG.leftMultiplyLeftCompactForm(m);
+        return (GF2Vector)mG.add(z);
+    }
+
+    /**
+     * The McEliece decryption primitive.
+     *
+     * @param privKey the private key
+     * @param c       the ciphertext vector <tt>c = m*G + z</tt>
+     * @return the message vector <tt>m</tt> and the error vector <tt>z</tt>
+     */
+    public static GF2Vector[] decryptionPrimitive(
+        McElieceCCA2PrivateKeyParameters privKey, GF2Vector c)
+    {
+
+        // obtain values from private key
+        int k = privKey.getK();
+        Permutation p = privKey.getP();
+        GF2mField field = privKey.getField();
+        PolynomialGF2mSmallM gp = privKey.getGoppaPoly();
+        GF2Matrix h = privKey.getH();
+        PolynomialGF2mSmallM[] q = privKey.getQInv();
+
+        // compute inverse permutation P^-1
+        Permutation pInv = p.computeInverse();
+
+        // multiply c with permutation P^-1
+        GF2Vector cPInv = (GF2Vector)c.multiply(pInv);
+
+        // compute syndrome of cP^-1
+        GF2Vector syndVec = (GF2Vector)h.rightMultiply(cPInv);
+
+        // decode syndrome
+        GF2Vector errors = GoppaCode.syndromeDecode(syndVec, field, gp, q);
+        GF2Vector mG = (GF2Vector)cPInv.add(errors);
+
+        // multiply codeword and error vector with P
+        mG = (GF2Vector)mG.multiply(p);
+        errors = (GF2Vector)errors.multiply(p);
+
+        // extract plaintext vector (last k columns of mG)
+        GF2Vector m = mG.extractRightVector(k);
+
+        // return vectors
+        return new GF2Vector[]{m, errors};
+    }
+
+}