GNUnet++ - High level C++ wrapper for GNUnet

Why GNUnet++?

IMO GNUnet is a cool project which shows what decentralized systems could look like. However the time to first hello world is way too long, API is not well documented and everything is written GNU style C. Which are all factors against it's adoption. GNUnet++ wraps all the C-ness into a (more or less) modern C++ style highlevel API. Provides proper lifetime management and an easier learning path. Hopefully leading to a better development experience.

IMPORTAN: This is not a part of the GNUnet project. The author created it because he wants to use GNUnet in C++.

ALSO IMPORTANT: Don't expect the code base be clean. GNUnet is a very C project. Lifetime managment is all over the place. I did my best to create a sane API out of it. Nor it is production ready. The API might go through major changes in the future. Nor ABI stability is guaranteed.

Show me some code!

The DHT class provides easy access to GNUnet's DHT. It's API is designed to look like OpenDHT's for more familiarity to potential users. Note that need GNUnet running on your system before running the samples.

// Max 32 simultaneous operations
auto dht = std::make_shared<DHT>(cfg, 32);

...
dht->put("Answer", "42");
dht->get("some_super_secret", [](const std::string_view data) {
   std::cout << "super secret info: " << data << std::endl;
   return true; // keep on searching after the current one.
   // return false to cancel futher lookups.
}, std::chrono::seconds(30)); // Max searching for 30 seconds

Makes CADET much easier to use.

auto cadet = std::make_shared<CADET>(cfg);
auto channel = cadet->connect("SOME_PEER_ID", "PORT_NAME");
channel->setReceiveCallback([](const std::string_view data, uint16_t type) {
   std::cout << "Received: " << data << std::endl;
});
channel->send("Hello World!", GNUNET_MESSAGE_TYPE_CADET_CLI);

Search and download files from the GNUnet File Sharing service.

FS::search({"jpg"}, [](const std::string_view uri, const std::string_view name) {
   std::cout << "Found " << filename << " at " << uri << std::endl;
   return true;
}, std::chrono::seconds(30));

FS::downlad("gnunet://fs/...", "foobar.jpg", [](DownloadStatus status) {
    if(status == DownloadStatus::Completed)
      // yay! we're done
});

Wich generates the following output

Found IMG_20220528_134243_161.jpg at gnunet://fs/chk/N59XZ8KPMQ0975JBTPV9AGEAD5T7V694QYWNK21683Q74TTRMQB2CHW4AZVTM3A5NFC57K0N6PD5EGCGMJABTZ6HKMV9ZC1T52FTVSG.2RJ19QYFPBJ2TBMZSNECXP9KHDTX90B6ZCTBSJYQKPK016156HNCPE5RJMNEM3A1NTRHMVWK8GCJ1MVG4S25F8A4TW1S70PCDMSG94R.2778934

Found 1651945314526m.jpg at gnunet://fs/chk/R4MCF6MTQDR4VKKKMD1H8PD9THRKGV1ER0BXP57BKVT2580KW7S25HFSW7MK0BM1JBPBEHG6P0SHDHDERX7MTPFA5YE68E7Q43H8Z78.4J604CQR9AESPQ3X894PE2P56X3P21QJWBBQQXH4SR07X4KXX5TBH62BHSDT6HWY70XP5DZB5S5FADDJ7TDYENEX67H4JN6Q1KP725G.91907

Found ball.jpg at gnunet://fs/chk/3ZJRZJRDD6V6R54TG9VAC4G3ZQ4WGZ5ZVSP5BZ12X004CYTGDNTB9P8STZ0P1Y2REB28EA8FZ3JZ4900V5FVEMYAESDWVGATZ37WJAR.46BHSJS8BXTT6KN4NTBS66VAYSDKRFST71439H6RAAKPT294T3ECY6AEQCN726ZQXW039YD7Z0Q17385HMH8RQWT92AR8AQ4B47X60R.241099
...

Examples with comments can be found in the examples directory.

Requirments

First you need the dependencies

• C++20 capable compiler
  • Tested with GCC 12.1 and Clang 14.0
• A installation of GNUnet 0.19 (or likely the latest version)
• libidn

(For examples)

• CLI11

(For tests)

• Drogon (for the async test framework)

Roadmap

This project aims to create a easy to use wapper for the commonly used part of GNUnet.

• General

  • Move applicable APIs to C++ coroutines
  • Primitives to support multithreading
    • Allow other threads to wake GNUnet scheduler
  • Replace cppcoro
  • Port to C++ modules when CMake supports it

• CMake

  • Locate GNUnet installation path (currently use the expected path)
  • Find libidn

• DHT

  • Basic operations (put/get)
  • Monitor

• File Sharing

  • Download
  • Publish
  • Search
  • Unindex

• Crypto

  • Hash
  • HMAC
  • ECDSA/EDDSA
  • to_string
  • RSA
  • Signatures

• CADET

  • Server
  • Client

• GNS

  • Resolve

• Namestore

  • Register/modify record
  • Lookup record in zone

• Identity

  • Create
  • Delte
  • Get Ego
  • List

• NSE (Network Size Estimatior)

  • Get value
  • Watch value

• PeerInfo

  • List peers
  • Add peer
  • Hello message to URI
    • Partially done. Current method depends on ABI of transport plugins not changing.
    • However, it is memory safe.
  • Parse HELLO URI

• Scheduler

  • Delayed run
  • Run on exit
  • Run immidately

• Messenger

  • Send/receive basic messages
  • Joining via doors
  • Send/receive files
  • API to send non-text messages

• Overall cleanup

  • Enforce memory safety and track all raw pointers