[![Latest Version]][crates.io] [![Documentation]][docs.rs] ![License]

`asn-db2` is a Rust library that can load and index [ASN] databases (`ip2asn-v4.tsv`, `ip2asn-v6.tsv`, `ip2asn-combined.tsv` files) from [IPtoASN] website.

*This crate is a rewritten fork of Jakub Pastuszek's [asn-db] crate.*

Once loaded it can be used to lookup an IP address for matching [ASN] record that contains:

* network base IP address and mask (e.g. [ipnet::Ipv4Net](https://docs.rs/ipnet/2.3.0/ipnet/struct.Ipv4Net.html) value like `1.1.1.0/24`),
* assigned AS number (e.g. `13335`),
* owner country code (e.g. `US`),
* owner information (e.g. `CLOUDFLARENET - Cloudflare, Inc.`).

Both IPv4 and IPv6 addresses and networks are supported.

# Example

Load database from `ip2asn-v4.tsv` file and lookup `1.1.1.1` IP address.

```rust
use asn_db2::Ipv4Database;
use std::fs::File;
use std::io::BufReader;

let db = Ipv4Database::from_reader(BufReader::new(File::open("ip2asn-v4.tsv").unwrap())).unwrap();
let entry = db.lookup("1.1.1.1".parse().unwrap()).unwrap();

println!("{:#?}", entry);
```

This prints:

```noformat
Entry {
    subnet: 1.1.1.0/24,
    as_number: 13335,
    country: "US",
    owner: "CLOUDFLARENET",
}
```

[asn-db]: https://crates.io/crates/asn-db
[ASN]: https://en.wikipedia.org/wiki/Autonomous_system_%28Internet%29#Assignment
[IPtoASN]: https://iptoasn.com/
[crates.io]: https://crates.io/crates/asn-db2
[Latest Version]: https://img.shields.io/crates/v/asn-db2.svg
[Documentation]: https://docs.rs/asn-db2/badge.svg
[docs.rs]: https://docs.rs/asn-db2
[License]: https://img.shields.io/crates/l/asn-db2.svg