keynub_licdongle 1.1.1

Client for the KeyNub USB license dongle: verify that a dongle is genuine, read and write its license records, use its counters and encrypt data so that only a dongle can decrypt it. Pure Dart over th [...]

KeyNub License Dongle — Dart package

import 'package:keynub_licdongle/keynub_licdongle.dart';

final ctx = Context();
final dongle = ctx.open();                    // first dongle, or ctx.open(serial: ...)
dongle.verifyGenuine();                       // throws unless genuine
final data = dongle.withSession((s) =>        // closed on every exit path
    s.appDecrypt(sealed));                    // <- build the licence check on this
dongle.close();
ctx.close();

Pure Dart. The package is dart:ffi over the SDK's C library, and the library is loaded at run time, so there is no build step, no plugin glue and nothing in the path of the check that a customer could substitute. It works in Dart command-line programs and in Flutter desktop applications on Windows, Linux and macOS alike; package:ffi is the one dependency, for memory the C side reads.

Setup

dart pub add keynub_licdongle

The package does not carry the native library. Take keynub_licdongle for your platform from the SDK's natives folder and either put it where the operating system finds libraries (next to the executable, or on PATH, LD_LIBRARY_PATH, DYLD_LIBRARY_PATH), or name it before the first call:

LicDongleLibrary.path = '/opt/keynub/libkeynub_licdongle.so';

KEYNUB_LICDONGLE_LIBRARY in the environment does the same. In a clone of the SDK repository the package finds natives/<platform>/ on its own, from the script's directory and the working directory upwards, so the samples run with nothing set. A process loads the library once; LicDongleLibrary.loadedPath tells which. For a Flutter application, bundle the library with the platform build (the Windows and Linux runners take it as a CMake install target, macOS as a framework or dylib in the bundle) and set LicDongleLibrary.path from Platform.resolvedExecutable. On Linux, install the udev rule described in NATIVES.md so the dongle is accessible without root.

Notes

• Results are plain classes (Info, GenuineResult, DeviceInfo, RecordInfo); byte data is Uint8List, and every call taking bytes also takes a String for its UTF-8. The C structures are dart:ffi Structs whose field types mirror the header, so Dart computes the padding.
• Failures throw LicenseDongleError with status (Status.noDevice, .notGenuine, .authRequired, ...), operation and detail; loading problems throw LibraryLoadError.
• dongle.isGenuine is the non-throwing form for a gate and fails closed.
• dongle.withSession((s) => ...) closes the session afterwards, whatever happens; openSession() gives a Session to close yourself.
• readRecord and writeRecord take progress: (done, total) => bool; returning false cancels. An exception thrown inside the callback cancels the transfer and is rethrown after the C frames have unwound, never through them.
• eraseAllRecords() is deliberately separate from eraseRecord(name): to the C library a null name means "erase every record", and an accidentally empty string must not do that.
• Close what you open: a context closes the dongles still open on it, and a dongle closes when its context does.

Read docs/integration-security.md before writing the check. if (!dongle.isGenuine) exit(1) is one line to delete, and a Dart or Flutter application ships as an AOT snapshot that tools read well enough to find it. Route something the program needs through appEncrypt/appDecrypt, so removing the check removes the data.

Tests

dart test runs without a dongle: it compiles a stand-in for the C ABI (bindings/julia/test/stub/licd_stub.c of the SDK repository) with a C compiler from the path and exercises every call against it.

Links

• KeyNub License Dongle for Dart and Flutter: the product, and how to order one
• Source, samples and issue tracker on GitHub
• Native library for your platform