org.bouncycastle.crypto.bls

Class BLS12_381Aggregation

java.lang.Object

org.bouncycastle.crypto.bls.BLS12_381Aggregation

public class BLS12_381Aggregation
extends java.lang.Object

Helper for aggregating BLS12-381 signatures and verifying aggregates.

Aggregation itself is suite-independent — it is just point addition in G2. The aggregate-verify equation e(G1_gen, sig_agg) == prod_i e(pk_i, H(msg_i)) collapses to a single multi-pairing check multiPair([(-G1_gen, sig_agg), (RK_1, H_1), ...]) == 1, where each H_i is a distinct hashed-message G2 point and RK_i is the sum of all public keys that signed the corresponding message — the "QK_set" aggregation from draft-irtf-cfrg-bls-signature sec. 2.9. Each suite computes its own list of hashed-message G2 points (BasicScheme: H(msg) with NUL DST; MessageAugmentation: H(pk || msg) with AUG DST; ProofOfPossession: H(msg) with POP DST) and then defers to aggregateVerifyHashed(org.bouncycastle.math.ec.ECPoint[], org.bouncycastle.crypto.bls.BLS12_381G2Point[], org.bouncycastle.crypto.bls.BLS12_381G2Point), which performs the message-grouping plus a single final exponentiation regardless of how many signers participated.

Method Summary

Modifier and Type	Method and Description
static BLS12_381G2Point	aggregate(BLS12_381G2Point[] signatures) Aggregate a list of BLS signatures by summing them in G2.

Methods inherited from class java.lang.Object

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

Method Detail

aggregate

public static BLS12_381G2Point aggregate(BLS12_381G2Point[] signatures)

Aggregate a list of BLS signatures by summing them in G2.

Parameters:

signatures - one or more BLS signatures (G2 points). Must be non-empty.

Returns:

sig_1 + sig_2 + ... + sig_n.