win32

Windows dynamic libraries, calling conventions, and transmute Sep 28, 2019 18 minute read networking protocols icmp win32 rust ffi

So, how does ping.exe actually send a ping? It seems unrealistic that ping.exe itself implements all the protocols involved in sending a ping. So it must be calling some sort of library. Also, since it ends up talking to the outside world via a NIC (network interface...

FFI-safe types in Rust, newtypes, MaybeUninit, and references vs pointers Sep 30, 2019 14 minute read networking protocols icmp win32 rust ffi

It’s time to make sup, our own take on ping, use the Win32 APIs to send an ICMP echo. Earlier we discovered that Windows’s ping.exe used IcmpSendEcho2Ex. But for our purposes, the simpler IcmpSendEcho will do just fine.

As we mentioned earlier, it’s provided...

Designing and implementing a safer API on top of LoadLibrary Oct 4, 2019 17 minute read networking protocols icmp win32 rust ffi dns

It’s refactor time!

Our complete program is now about a hundred lines, counting blank lines (see the end of part 3 for a complete listing).

While this is pretty good for a zero-dependency project (save for pretty-hex), we can do better.

First off, concerns are mixed...

A simple ping library, parsing strings into IPv4 address Oct 12, 2019 13 minute read networking protocols icmp rust ffi win32

We’ve just spent a lot of time abstracting over LoadLibrary, but we still have all the gory details of the Win32 ICMP API straight in our main.rs file! That won’t do.

This time will be much quicker, since we already learned about carefully designing an API, hiding...

The builder pattern, and a macro that keeps FFI code DRY Oct 12, 2019 12 minute read networking protocols icmp rust ffi win32

Our ping API is simple, but it’s also very limited:

pub fn ping(dest: ipv4::Addr) -> Result<(), String>

// called as:
ping(ipv4::Addr([8, 8, 8, 8])).unwrap();

It doesn’t allow specifying the TTL (time to live) of packets, it doesn’t allow...

amos loves to tinker

It’s refactor time!