feature request: Support OpenBSD

[Pyvonix]

The tun crates is a dependency of the project that I'm trying to build on my OpenBSD.

While compiling it, the compiler crashes with the following errors:

error[E0432]: unresolved import `crate::platform::PlatformConfig`
  --> /root/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tun-0.7.13/src/configuration.rs:20:5
   |
20 | use crate::platform::PlatformConfig;
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ no `PlatformConfig` in `platform`
   |
...
error[E0432]: unresolved import `crate::platform::create`
  --> /home/builder/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tun-0.7.13/src/async/mod.rs:20:5
   |
20 | use crate::platform::create;
   |     ^^^^^^^^^^^^^^^^^^^^^^^ no `create` in `platform`
   |
...
error[E0432]: unresolved import `crate::platform::Device`
  --> /home/builder/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tun-0.7.13/src/async/unix_device.rs:26:5
   |
26 | use crate::platform::Device;
   |     ^^^^^^^^^^^^^^^^^^^^^^^ no `Device` in `platform`
...
error[E0425]: cannot find value `TUN_PROTO_IP6` in this scope
  --> /home/builder/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tun-0.7.13/src/platform/posix/split.rs:58:25
   |
58 |             return Some(TUN_PROTO_IP6);
   |                         ^^^^^^^^^^^^^ not found in this scope
error[E0425]: cannot find value `TUN_PROTO_IP4` in this scope
  --> /home/builder/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tun-0.7.13/src/platform/posix/split.rs:60:25
   |
60 |             return Some(TUN_PROTO_IP4);
   |                         ^^^^^^^^^^^^^ not found in this scope

Some errors have detailed explanations: E0425, E0432.
For more information about an error, try `rustc --explain E0425`.
error: could not compile `tun` (lib) due to 5 previous errors
warning: build failed, waiting for other jobs to finish..

Some information about the system:

• OpenBSD 7.7 amd64
• cargo 1.85.0 (d73d2caf9 2024-12-31)
• rustc 1.85.0 (4d91de4e4 2025-02-17) (built from a source tarball)

Thank you in advance if you have an idea to correct this.

[Pyvonix]

Just build the tun-0.7.13 crates:

   Compiling tun v0.7.13 (/home/builder/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tun-0.7.13)
error[E0432]: unresolved import `crate::platform::PlatformConfig`
  --> src/configuration.rs:20:5
   |
20 | use crate::platform::PlatformConfig;
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ no `PlatformConfig` in `platform`
   |
[...]
error[E0425]: cannot find value `TUN_PROTO_IP6` in this scope
  --> src/platform/posix/split.rs:58:25
   |
58 |             return Some(TUN_PROTO_IP6);
   |                         ^^^^^^^^^^^^^ not found in this scope

error[E0425]: cannot find value `TUN_PROTO_IP4` in this scope
  --> src/platform/posix/split.rs:60:25
   |
60 |             return Some(TUN_PROTO_IP4);
   |                         ^^^^^^^^^^^^^ not found in this scope

Some errors have detailed explanations: E0425, E0432.
For more information about an error, try `rustc --explain E0425`.
error: could not compile `tun` (lib) due to 3 previous errors

[ssrlive]

Not support OpenBSD yet.

[Pyvonix]

Well. Can I change this issue to “feature request: Support OpenBSD” when it will be possible?

[ssrlive]

PRs welcome

[zonyitoo]

https://man.openbsd.org/tun.4

OpenBSD's man didn't provide enough detail about how to use tun/tap devices. But it should work very simimar to FreeBSD:

https://github.com/meh/rust-tun/blob/master/src/platform/freebsd/device.rs

Maybe @Pyvonix you could try to make a local patch and reuse FreeBSD's implementation on OpenBSD and see what has to be changed based on the output.