1 files changed, 68 insertions, 0 deletions
diff --git a/core/src/main/java/org/spongycastle/crypto/agreement/jpake/JPAKERound2Payload.java b/core/src/main/java/org/spongycastle/crypto/agreement/jpake/JPAKERound2Payload.java
new file mode 100644
index 00000000..3df5c7b9
--- /dev/null
+++ b/core/src/main/java/org/spongycastle/crypto/agreement/jpake/JPAKERound2Payload.java
@@ -0,0 +1,68 @@
+package org.spongycastle.crypto.agreement.jpake;
+
+import java.math.BigInteger;
+
+import org.spongycastle.util.Arrays;
+
+/**
+ * The payload sent/received during the second round of a J-PAKE exchange.
+ * <p>
+ * Each {@link JPAKEParticipant} creates and sends an instance
+ * of this payload to the other {@link JPAKEParticipant}.
+ * The payload to send should be created via
+ * {@link JPAKEParticipant#createRound2PayloadToSend()}
+ * <p>
+ * Each {@link JPAKEParticipant} must also validate the payload
+ * received from the other {@link JPAKEParticipant}.
+ * The received payload should be validated via
+ * {@link JPAKEParticipant#validateRound2PayloadReceived(JPAKERound2Payload)}
+ */
+public class JPAKERound2Payload
+{
+    /**
+     * The id of the {@link JPAKEParticipant} who created/sent this payload.
+     */
+    private final String participantId;
+
+    /**
+     * The value of A, as computed during round 2.
+     */
+    private final BigInteger a;
+
+    /**
+     * The zero knowledge proof for x2 * s.
+     * <p/>
+     * This is a two element array, containing {g^v, r} for x2 * s.
+     */
+    private final BigInteger[] knowledgeProofForX2s;
+
+    public JPAKERound2Payload(
+        String participantId,
+        BigInteger a,
+        BigInteger[] knowledgeProofForX2s)
+    {
+        JPAKEUtil.validateNotNull(participantId, "participantId");
+        JPAKEUtil.validateNotNull(a, "a");
+        JPAKEUtil.validateNotNull(knowledgeProofForX2s, "knowledgeProofForX2s");
+
+        this.participantId = participantId;
+        this.a = a;
+        this.knowledgeProofForX2s = Arrays.copyOf(knowledgeProofForX2s, knowledgeProofForX2s.length);
+    }
+
+    public String getParticipantId()
+    {
+        return participantId;
+    }
+
+    public BigInteger getA()
+    {
+        return a;
+    }
+
+    public BigInteger[] getKnowledgeProofForX2s()
+    {
+        return Arrays.copyOf(knowledgeProofForX2s, knowledgeProofForX2s.length);
+    }
+
+}