sctp-socket: A C repository from djberg96

Description

A Ruby interface for SCTP sockets.

Prerequisites

You will need the sctp development headers installed.

On some systems, such as RHEL8 or later, you may need to enable the sctp module.

Installation

gem install sctp-socket

Installing the Trusted Cert

gem cert --add <(curl -Ls https://raw.githubusercontent.com/djberg96/sctp-socket/main/certs/djberg96_pub.pem)

About SCTP

The Stream Control Transmission Protocol (SCTP) is a message oriented, reliable transport protocol with direct support for multihoming that runs on top of ip, and supports both v4 and v6 versions.

Like TCP, SCTP provides reliable, connection oriented data delivery with congestion control. Unlike TCP, SCTP also provides message boundary preservation, ordered and unordered message delivery, multi-streaming and multi-homing.

Detection of data corruption, loss of data and duplication of data is achieved by using checksums and sequence numbers. A selective retransmission mechanism is applied to correct loss or corruption of data.

Synopsis

# sample_server.rb
require 'sctp/socket'

begin
  port = 62324
  socket = SCTP::Socket.new
  socket.bindx(:port => port, :addresses => ['10.0.5.4', '10.0.6.4'])
  socket.set_initmsg(:output_streams => 5, :input_streams => 5, :max_attempts => 4)
  socket.subscribe(:data_io => true)
  socket.listen

  while true
    data = socket.recvmsg
    puts data
  end
ensure
  socket.close
end

Future Plans

Add more specs.
Subclass the Socket class (but see known issues below).
Create a wrapper for the usrlibsctp implementation using FFI.

Known Issues

Currently this has only been developed and tested on Linux. Other platforms will probably only be supported via community contributions.

The sendv and recvv methods may not be available. Use the sendmsg and recvmsg methods instead.

I am currently unable to subclass the Socket class from Ruby's standard library. For whatever reason the call to rb_call_super works, but the fileno is always set to nil. I think it's getting confused by the IPPROTO_SCTP value for the protocol, but I haven't nailed it down yet.

Please report any issues on the github project page.

https://github.com/djberg96/sctp-socket

More Information on SCTP

https://www.linuxjournal.com/article/9748
https://www.linuxjournal.com/article/9749
https://www.linuxjournal.com/article/9784
SCTP in Theory and Practice - Svetomir Dimitrov
Stream Control Transmission Protocol (A Reference Guide) - Randall Stewart and Qiaobing Xie

djberg96/sctp-socket