chainsafe-bls/test/unit/index.test.ts

import {expect} from "chai";
import {IBls} from "../../src/interface";
import {getN, randomMessage} from "../util";
import {hexToBytes} from "../../src/helpers";
import {maliciousVerifyMultipleSignaturesData} from "../data/malicious-signature-test-data";

export function runIndexTests(bls: IBls): void {
  // eslint-disable-next-line @typescript-eslint/explicit-function-return-type
  function getRandomData() {
    const sk = bls.SecretKey.fromKeygen();
    const pk = sk.toPublicKey();
    const msg = randomMessage();
    const sig = sk.sign(msg);
    return {sk, pk, msg, sig};
  }

  describe("verify", () => {
    it("should verify signature", () => {
      const {pk, msg, sig} = getRandomData();
      const pkHex = pk.toHex();
      const isValid = bls.verify(pk.toBytes(), msg, sig.toBytes());
      expect(isValid, "fail verify").to.be.true;

      // Make sure to not modify original pubkey when verifying
      expect(pk.toHex()).to.be.equal(pkHex, "pubkey modified when verifying");
    });

    it("should fail verify empty signature", () => {
      const {pk, msg} = getRandomData();
      const emptySig = Buffer.alloc(96);
      const isValid = bls.verify(pk.toBytes(), msg, emptySig);
      expect(isValid).to.be.false;
    });

    it("should fail verify signature of different message", () => {
      const {pk, sig} = getRandomData();
      const msg2 = randomMessage();
      const isValid = bls.verify(pk.toBytes(), msg2, sig.toBytes());
      expect(isValid).to.be.false;
    });

    it("should fail verify signature signed by different key", () => {
      const {msg, sig} = getRandomData();
      const {pk: pk2} = getRandomData();
      const isValid = bls.verify(pk2.toBytes(), msg, sig.toBytes());
      expect(isValid).to.be.false;
    });
  });

  describe("verify multiple", () => {
    it("should verify aggregated signatures", () => {
      const sks = getN(4, () => bls.SecretKey.fromKeygen());
      const msgs = getN(2, () => randomMessage());
      const pks = sks.map((sk) => sk.toPublicKey());

      const sigs = [sks[0].sign(msgs[0]), sks[1].sign(msgs[0]), sks[2].sign(msgs[1]), sks[3].sign(msgs[1])];

      const aggPubkeys = [
        bls.aggregatePublicKeys([pks[0], pks[1]].map((pk) => pk.toBytes())),
        bls.aggregatePublicKeys([pks[2], pks[3]].map((pk) => pk.toBytes())),
      ];

      const aggSig = bls.aggregateSignatures(sigs.map((sig) => sig.toBytes()));

      expect(bls.verifyMultiple(aggPubkeys, msgs, aggSig), "should be valid").to.be.true;
      expect(bls.verifyMultiple(aggPubkeys.reverse(), msgs, aggSig), "should fail - swaped pubkeys").to.be.false;
    });

    it("should verify aggregated signatures - same message", () => {
      const n = 4;
      const msg = randomMessage();
      const sks = getN(n, () => bls.SecretKey.fromKeygen());
      const pks = sks.map((sk) => sk.toPublicKey());
      const sigs = sks.map((sk) => sk.sign(msg));

      const aggregateSignature = bls.aggregateSignatures(sigs.map((sig) => sig.toBytes()));

      const isValid = bls.verifyMultiple(
        pks.map((pk) => pk.toBytes()),
        getN(4, () => msg), // Same message n times
        aggregateSignature
      );
      expect(isValid).to.be.true;
    });

    it("should fail to verify aggregated signatures - no public keys", () => {
      const sig = Buffer.alloc(96);
      const msg1 = randomMessage();
      const msg2 = randomMessage();

      const isValid = bls.verifyMultiple([], [msg2, msg1], sig);
      expect(isValid).to.be.false;
    });
  });

  describe("verifyMultipleSignatures", () => {
    it("Should verify multiple signatures", () => {
      const n = 4;
      const dataArr = getN(n, () => {
        const sk = bls.SecretKey.fromKeygen();
        const pk = sk.toPublicKey();
        const msg = randomMessage();
        const sig = sk.sign(msg);
        return {pk, msg, sig};
      });
      const pks = dataArr.map((data) => data.pk);
      const msgs = dataArr.map((data) => data.msg);
      const sigs = dataArr.map((data) => data.sig);

      expect(bls.Signature.verifyMultipleSignatures(pks, msgs, sigs)).to.equal(true, "class interface failed");

      expect(
        bls.verifyMultipleSignatures(
          pks.map((pk) => pk.toBytes()),
          msgs,
          sigs.map((sig) => sig.toBytes())
        )
      ).to.equal(true, "functional (bytes serialized) interface failed");
    });

    it("Test fails correctly against a malicous signature", async () => {
      const pks = maliciousVerifyMultipleSignaturesData.pks.map(bls.PublicKey.fromHex);
      const msgs = maliciousVerifyMultipleSignaturesData.msgs.map(hexToBytes);
      const sigs = maliciousVerifyMultipleSignaturesData.sigs.map(bls.Signature.fromHex);

      maliciousVerifyMultipleSignaturesData.manipulated.forEach((isManipulated, i) => {
        expect(sigs[i].verify(pks[i], msgs[i])).to.equal(
          !isManipulated,
          isManipulated ? "Manipulated signature should not verify" : "Ok signature should verify"
        );
      });

      // This method (AggregateVerify in BLS spec lingo) should verify

      const dangerousAggSig = bls.Signature.aggregate(sigs);
      expect(dangerousAggSig.verifyMultiple(pks, msgs)).to.equal(
        true,
        "Malicious signature should be validated with bls.verifyMultiple"
      );

      // This method is expected to catch the malicious signature and not verify
      expect(bls.Signature.verifyMultipleSignatures(pks, msgs, sigs)).to.equal(
        false,
        "Malicous signature should not validate with bls.verifyMultipleSignatures"
      );
    });
  });
}