How to use the elliptic/lib/elliptic/ec/signature.js function in elliptic

const testSignature = function (msg) {
				const sig = cryptoUtils.sign(key, cryptoUtils.hash(msg));
				if (sig) {
				// test that signatures have low-S
					const halfOrder = halfOrdersForCurve[key._key.ecparams.name];
					const sigObject = new Signature(sig);
					if (sigObject.s.cmp(halfOrder) === 1) {
						t.fail('Invalid signature object: S value larger than N/2');
					} else {
						t.pass('Valid signature object generated from sign()');
					}

					// using internal calls to verify the signature
					const pubKey = cryptoUtils._ecdsa.keyFromPublic(key.getPublicKey()._key.pubKeyHex, 'hex');
					// note that the signature is generated on the hash of the message, not the message itself
					t.equal(pubKey.verify(cryptoUtils.hash(msg), Buffer.from(sig)), true,
						'CryptoSuite_ECDSA_AES function tests: sign() method produced proper signature that was successfully verified');
				} else {
					t.fail('Invalid signature generated by sign()');
				}
			};

var testSignature = function (msg) {
				var sig = cryptoUtils.sign(key, cryptoUtils.hash(msg));
				if (sig) {
					// test that signatures have low-S
					var halfOrder = halfOrdersForCurve[key._key.ecparams.name];
					var sigObject = new Signature(sig);
					if (sigObject.s.cmp(halfOrder) == 1) {
						t.fail('Invalid signature object: S value larger than N/2');
					} else {
						t.pass('Valid signature object generated from sign()');
					}

					// using internal calls to verify the signature
					var pubKey = cryptoUtils._ecdsa.keyFromPublic(key.getPublicKey()._key.pubKeyHex, 'hex');
					// note that the signature is generated on the hash of the message, not the message itself
					t.equal(pubKey.verify(cryptoUtils.hash(msg), new Buffer(sig)), true,
						'CryptoSuite_ECDSA_AES function tests: sign() method produced proper signature that was successfully verified');
				} else {
					t.fail('Invalid signature generated by sign()');
				}
			};

function _checkMalleability(sig, curveParams) {
    const curve = curveParams.name;
    const halfOrder = halfOrdersForCurve[curve];
    if (!halfOrder) {
        throw new Error(`Can not find the half order needed to calculate "s" value for immalleable signatures. Unsupported curve name: ${curve}`);
    }

    // first need to unmarshall the signature bytes into the object with r and s values
    const sigObject = new Signature(sig, 'hex');
    if (!sigObject.r || !sigObject.s) {
        throw new Error('Failed to load the signature object from the bytes.');
    }

    // in order to guarantee 's' falls in the lower range of the order, as explained in the above link,
    // first see if 's' is larger than half of the order, if so, it is considered invalid in this context
    if (sigObject.s.cmp(halfOrder) === 1) { // module 'bn.js', file lib/bn.js, method cmp()
        return false;
    }

    return true;
}

function _checkMalleability(sig, curveParams) {
	var halfOrder = halfOrdersForCurve[curveParams.name];
	if (!halfOrder) {
		throw new Error('Can not find the half order needed to calculate "s" value for immalleable signatures. Unsupported curve name: ' + curve);
	}

	// first need to unmarshall the signature bytes into the object with r and s values
	var sigObject = new Signature(sig, 'hex');
	if (!sigObject.r || !sigObject.s) {
		throw new Error('Failed to load the signature object from the bytes.');
	}

	// in order to guarantee 's' falls in the lower range of the order, as explained in the above link,
	// first see if 's' is larger than half of the order, if so, it is considered invalid in this context
	if (sigObject.s.cmp(halfOrder) == 1) { // module 'bn.js', file lib/bn.js, method cmp()
		return false;
	}

	return true;
}

function _checkMalleability(sig, curveParams) {
	const halfOrder = ordersForCurve[curveParams.name].halfOrder;
	if (!halfOrder) {
		throw new Error('Can not find the half order needed to calculate "s" value for immalleable signatures. Unsupported curve name: ' + curveParams.name);
	}

	// first need to unmarshall the signature bytes into the object with r and s values
	const sigObject = new Signature(sig, 'hex');
	if (!sigObject.r || !sigObject.s) {
		throw new Error('Failed to load the signature object from the bytes.');
	}

	// in order to guarantee 's' falls in the lower range of the order, as explained in the above link,
	// first see if 's' is larger than half of the order, if so, it is considered invalid in this context
	if (sigObject.s.cmp(halfOrder) === 1) { // module 'bn.js', file lib/bn.js, method cmp()
		return false;
	}

	return true;
}

_pkcs11Verify(pkcs11, pkcs11Session, key, digest, signature) {
		try {
			/*
			 * Restore ASN1 DER signature to raw signature.
			 * Error will be thrown if signature is not properly encoded.
			 */
			const rns = new ecsig(signature, 'hex');
			logger.debug(__func() + 'ECDSA R+S signature: ' +
				util.inspect(rns, {depth: null}));
			const sig = Buffer.concat([rns.r.toArrayLike(Buffer, '', 0),
				rns.s.toArrayLike(Buffer, '', 0)]);
			logger.debug(__func() + 'ECDSA RAW signature: ' +
				util.inspect(sig, {depth: null}));
			/*
			 * key can be either a private or a public key.
			 */
			pkcs11.C_VerifyInit(pkcs11Session,
				{mechanism: pkcs11js.CKM_ECDSA},
				key._handle);
			return pkcs11.C_Verify(pkcs11Session, digest, sig);
		} catch (e) {
			/*
			 * Error is thrown when signature verification fails.

/*
			* key has been checked to be an ECDSA private key.
			*/
		pkcs11.C_SignInit(pkcs11Session, {mechanism: pkcs11js.CKM_ECDSA},
			key._handle);
		const sig = pkcs11.C_Sign(pkcs11Session, digest,
			Buffer.alloc(this._keySize));
		logger.debug(__func() + 'ECDSA RAW signature: ' +
			util.inspect(sig, {depth: null}));
		/*
			* ASN1 DER encoding against malleability.
			*/
		const r = new BN(sig.slice(0, sig.length / 2).toString('hex'), 16);
		const s = new BN(sig.slice(sig.length / 2).toString('hex'), 16);
		const signature = _preventMalleability({r: r, s: s}, this._ecdsaCurve);
		const der = (new ecsig({r: signature.r, s: signature.s})).toDER();
		logger.debug(__func() + 'ECDSA DER signature: ' +
			util.inspect(Buffer.from(der), {depth: null}));
		return Buffer.from(der);
	}