Dart should allow arbitrary network I/O

[Hixie]

Right now Dart allows you to do TCP and UDP networking, but there's no facilities for ARP, ICMP, or other IP protocols.

[komapeb]

ICMP would be super useful for a current project of mine.

[sortie]

Can you elaborate a bit more on the need and priority for this?

ARP is a link layer protocol and is not built on top of the IP protocol. You'd need raw access to the network interface to do this, not just the the IP layer. This is normally handled at the OS level and implementing access would probably require a software network interface.

ICMP is on the IP layer and can be done with a raw raw socket. This is exposed as raw sockets, but is generally something you want the OS to handle for you. The needs you might have can usually be set on the socket with socket options, although Dart does not expose many of those.

These kinds of interfaces require root access or specially set up permissions. They are rare uses that mostly the OS should concern itself with unless one happens to be writing systems software, which isn't really what Dart has been designed for.

[gaetschwartz]

@sortie ICMP can be useful in multiple ways and I think it would be great to expose a way to use it. I tried to do so by using RawSocket as you just mentioned but didn't manage to make it work. Isn't RawSocket TCP only ?

[sortie]

RawSocket is raw in terms of API, not protocol. It's just like Socket in that it also uses TCP.

Please clarify how you find ICMP useful. For some of the use cases, there are socket options you can set on the TCP sockets to change the kernel's behavior, maybe that's what you're looking for. Note that we cannot easily expose low level protocols like ICMP and ARP as this kind of raw access requires the code to run as root and dart:io generally doesn't expose very specific low level OS functionality. It e.g. wouldn't be possible to provide this functionality from a Flutter application because they don't run as root.

[gaetschwartz]

Well I'm not really familiar with how the different platforms use and give access to ICMP but it is really useful for any Internet diagnostic app, ping computing etc. I would agree that ARP wouldn't be useful though.

[sortie]

We don't have any plans for implementing ARP, ICMP, or raw IP sockets in Dart at this point. They're generally low level and unportable facilities that in most cases requires Dart to run with administrative privileges.

If anyone has a well defined use case for these protocols, please comment.

[flukejones]

I was in need of built in ICMP so I can ping a remote machine over TCP.

[ahmtcn123]

I was in need of built in ICMP so I can ping a remote machine over TCP.

Me too, is there any update?

[Ephenodrom]

ICMP would be nice so you can create a traceroute with pure dart. Currently android has build in "ping" command that can be called with

Process.start("ping", ['-c $times', '-i 1', address]);

But there is no traceroute so far. So the only solution would be to build in some C code to run via FFI or some Kotlin code ... Would be much better to be able to do this with Dart.

[vannevar-morgan]

ICMP would be nice so you can create a traceroute with pure dart

Agreed

[Ephenodrom]

Just an update to an usecase. I created a DNS and Network checking App that works quite well on Android and iOS. Now i wanted to create an MacOS App. I am facing now a problem that i am not able to call the ping command line programm from within the App in MacOS.

I would like to recreate the ping tool in pure Dart. No way so far without ICMP.

As Dart and Flutter are considered to be used on many platforms, they should allow to do a lot of basic stuff like ICMP or DNS, due to you can't be sure if this is provided by the platform it runs.

The DNS problem can be solved by using the Google DNS JSON API. But i am not sure if that is available in every country.