Example #1
0
func (t *AssetManagementChaincode) init(stub *shim.ChaincodeStub, args []string) ([]byte, error) {
	myLogger.Info("[AssetManagementChaincode] Init")
	if len(args) != 0 {
		return nil, errors.New("Incorrect number of arguments. Expecting 0")
	}

	// Create ownership table
	err := stub.CreateTable("AssetsOwnership", []*shim.ColumnDefinition{
		&shim.ColumnDefinition{"Asset", shim.ColumnDefinition_STRING, true},
		&shim.ColumnDefinition{"Owner", shim.ColumnDefinition_BYTES, false},
	})
	if err != nil {
		return nil, errors.New("Failed creating AssetsOnwership table.")
	}

	// Set the admin
	// The metadata will contain the certificate of the administrator
	adminCert, err := stub.GetCallerMetadata()
	if err != nil {
		return nil, errors.New("Failed getting metadata.")
	}
	if len(adminCert) == 0 {
		return nil, errors.New("Invalid admin certificate. Empty.")
	}

	stub.PutState("admin", adminCert)

	return nil, nil
}
Example #2
0
func (t *AssetManagementChaincode) isCaller(stub *shim.ChaincodeStub, certificate []byte) (bool, error) {
	// In order to enforce access control, we require that the
	// metadata contains the signature under the signing key corresponding
	// to the verification key inside certificate of
	// the payload of the transaction (namely, function name and args) and
	// the transaction binding (to avoid copying attacks)

	// Verify \sigma=Sign(certificate.sk, tx.Payload||tx.Binding) against certificate.vk
	// \sigma is in the metadata

	sigma, err := stub.GetCallerMetadata()
	if err != nil {
		return false, errors.New("Failed getting metadata")
	}
	payload, err := stub.GetPayload()
	if err != nil {
		return false, errors.New("Failed getting payload")
	}
	binding, err := stub.GetBinding()
	if err != nil {
		return false, errors.New("Failed getting binding")
	}

	myLogger.Debug("passed certificate [% x]", certificate)
	myLogger.Debug("passed sigma [% x]", sigma)
	myLogger.Debug("passed payload [% x]", payload)
	myLogger.Debug("passed binding [% x]", binding)

	return stub.VerifySignature(
		certificate,
		sigma,
		append(payload, binding...),
	)
}