pgp

OpenPGP and Sequoia for Dart, backed by the pgp-ffi Rust crate.

package:pgp is the Flutter-free, pure-Dart dart:ffi binding over a prebuilt native library (libpgp_ffi.{so,dylib,dll}). It does not ship or build the binary for you; build the crate first (see Building the native library). A separate pgp_flutter package will build and bundle it via cargokit for Flutter apps.

Getting started

Add the package:

dart pub add pgp

Generate a certificate, share its public key, encrypt/decrypt, sign/verify, and export the secret key for storage:

import 'package:pgp/pgp.dart';

void main() {
  final pgp = PGP();
  final cert = pgp.generateKey('someone@example.org');
  final publicCert = pgp.certificateFromArmored(cert.exportPublicArmored());

  final encrypted = publicCert.encrypt('hello');
  print(cert.decrypt(encrypted));

  final signed = cert.sign('hello');
  print(publicCert.verify(signed));

  print(cert.exportSecretArmored());
  publicCert.dispose();
  cert.dispose();
}

The package intentionally exposes common certificate and message workflows, not the full OpenPGP packet/keyserver surface:

• generate certificates with encryption and signing subkeys
• import and export ASCII-armored public and secret certificates
• encrypt/decrypt ASCII-armored text messages
• sign/verify ASCII-armored text messages
• add/revoke user IDs, add/revoke subkeys, and revoke certificates

See example/pgp_example.dart for the supported operations in one program. Build the native library first, then run it from the package root:

dart run example/pgp_example.dart

Building the native library

The package loads libpgp_ffi at runtime via DynamicLibrary.open. The crate lives in the pgp-ffi git submodule; build it with cargo:

git submodule update --init   # fetch pgp-ffi if needed
cargo build --release --manifest-path pgp-ffi/Cargo.toml

The artifact lands in pgp-ffi/target/release/: libpgp_ffi.so (Linux), libpgp_ffi.dylib (macOS), or pgp_ffi.dll (Windows).

The loader searches that directory relative to the current directory, so running from the package root works without copying anything. For a compiled executable, put the library on the dynamic library search path: next to the executable (or its lib/), in the working directory (or its lib/), or on LD_LIBRARY_PATH / DYLD_LIBRARY_PATH / PATH. If loading fails, the package throws an ArgumentError listing every path it tried.

Development

• To generate the lib/src/pgp-ffi_bindings_generated.dart bindings for the pgp-ffi C header:

  dart run ffigen --config ffigen.yaml
  

• New bindings expose opaque pointers and status codes. Each native function needs a hand-written wrapper in lib/src/pgp_base.dart (see generateKey).