This is a Kotlin Multiplatform line-by-line transliteration port of keeperofdakeys/dns-lookup.

Original Project: This port is based on keeperofdakeys/dns-lookup. All design credit and project intent belong to the upstream authors; this repository is a faithful port to Kotlin Multiplatform with no behavioural changes intended.

This is an in-progress port. The goal is feature parity with the upstream Rust crate while providing a native Kotlin Multiplatform API. Every Kotlin file carries a // port-lint: source <path> header naming its upstream Rust counterpart so the AST-distance tool can track provenance.

The text below is reproduced and lightly edited from https://github.com/keeperofdakeys/dns-lookup/. It is the upstream project's own description and remains under the upstream authors' authorship; links have been rewritten to absolute upstream URLs so they continue to resolve from this repository.

A small wrapper for libc to perform simple DNS lookups.

You can use the lookup_host function to get a list of IP Addresses for a given hostname, and the lookup_name function to get the reverse dns entry for the given IP Address.

PS: If you only need a single result, consider ToSocketAddrs in libstd.

The library also includes a safe wrapper for getaddrinfo and getnameinfo.

Documentation

use dns_lookup::{lookup_host, lookup_addr};

{
  let hostname = "localhost";
  let ips: Vec<std::net::IpAddr> = lookup_host(hostname).unwrap().collect::<Vec<_>>();
  assert!(ips.contains(&"127.0.0.1".parse().unwrap()));
}

{
  let ip: std::net::IpAddr = "127.0.0.1".parse().unwrap();
  let host = lookup_addr(&ip).unwrap();

  // The string "localhost" on unix, and the hostname on Windows.
}

{
  extern crate dns_lookup;

  use dns_lookup::{getaddrinfo, AddrInfoHints, SockType};

  fn main() {
    let hostname = "localhost";
    let service = "ssh";
    let hints = AddrInfoHints {
      socktype: SockType::Stream.into(),
      .. AddrInfoHints::default()
    };
    let sockets =
      getaddrinfo(Some(hostname), Some(service), Some(hints))
        .unwrap().collect::<std::io::Result<Vec<_>>>().unwrap();

    for socket in sockets {
      // Try connecting to socket
      println!("{:?}", socket);
    }
  }
}

{
  use dns_lookup::getnameinfo;
  use std::net::{IpAddr, SocketAddr};

  let ip: IpAddr = "127.0.0.1".parse().unwrap();
  let port = 22;
  let socket: SocketAddr = (ip, port).into();

  let (name, service) = match getnameinfo(&socket, 0) {
    Ok((n, s)) => (n, s),
    Err(e) => panic!("Failed to lookup socket {:?}", e),
  };

  println!("{:?} {:?}", name, service);
  let _ = (name, service);
}

{
  use dns_lookup::gethostname;

  let hostname = gethostname().unwrap();
}

dependencies {
    implementation("io.github.kotlinmania:dns-lookup-kotlin:0.1.4")
}

./gradlew build
./gradlew test

• macOS arm64
• Linux x64
• Windows mingw-x64
• iOS arm64 / simulator-arm64 (Swift export + XCFramework)
• JS (browser + Node.js)
• Wasm-JS (browser + Node.js)
• Android (API 24+)

See AGENTS.md for translator discipline, port-lint header convention, and Rust → Kotlin idiom mapping.

This Kotlin port is distributed under the same MIT license as the upstream keeperofdakeys/dns-lookup. See LICENSE (and any sibling LICENSE-* / NOTICE files mirrored from upstream) for the full text.

Original work copyrighted by the dns-lookup authors.
Kotlin port: Copyright (c) 2026 Sydney Renee and The Solace Project.

Thanks to the keeperofdakeys/dns-lookup maintainers and contributors for the original Rust implementation. This port reproduces their work in Kotlin Multiplatform; bug reports about upstream design or behavior should go to the upstream repository.