community-id 0.2.4

This package provides a Rust implementation of the open Community ID flow hashing standard.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93

use std::net::IpAddr;

use crate::{ipv4, ipv6, IPPROTO_SCTP, IPPROTO_TCP, IPPROTO_UDP};

/// Main function to calculate community id.
///
/// # Arguments
/// * `seed` can be used to enable additional control over "domains" of Community ID usage. Default is 0.
/// * `src_ip` is the source ip of current packet.
/// * `dst_ip` is the dest ip of current packet.
/// * `src_port` is the source port when ip proto is TCP/UDP/SCTP, or icmp type when ip proto is ICMP/ICMPv6, or None otherwise.
/// * `dst_port` is the dest port when ip proto is TCP/UDP/SCTP, or icmp code when ip proto is ICMP/ICMPv6, or None otherwise.
/// * `ip_proto` is the protocol number.
/// * `disable_base64` can be used to disable base64 encoding.
pub fn calculate_community_id(
    seed: u16,
    src_ip: IpAddr,
    dst_ip: IpAddr,
    src_port: Option<u16>,
    dst_port: Option<u16>,
    ip_proto: u8,
    disable_base64: bool,
) -> Result<String, &'static str> {
    match ip_proto {
        IPPROTO_TCP | IPPROTO_UDP | IPPROTO_SCTP => {
            if src_port.is_none() || dst_port.is_none() {
                return Err("src port and dst port should be set when protocol is tcp/udp/sctp");
            }
        }
        _ => {}
    }

    match (src_ip, dst_ip) {
        (IpAddr::V4(src_ip), IpAddr::V4(dst_ip)) => ipv4::calculate_ipv4_community_id(
            seed,
            src_ip,
            dst_ip,
            src_port,
            dst_port,
            ip_proto,
            disable_base64,
        ),
        (IpAddr::V6(src_ip), IpAddr::V6(dst_ip)) => ipv6::calculate_ipv6_community_id(
            seed,
            src_ip,
            dst_ip,
            src_port,
            dst_port,
            ip_proto,
            disable_base64,
        ),
        _ => return Err("src ip and dst ip should be same version!"),
    }
}

#[cfg(test)]
mod tests {
    use std::net::Ipv4Addr;

    use super::*;

    #[test]
    fn test_calc() {
        let id = calculate_community_id(
            0,
            Ipv4Addr::new(1, 2, 3, 4).into(),
            Ipv4Addr::new(5, 6, 7, 8).into(),
            Some(1122),
            Some(3344),
            6,
            Default::default(),
        );
        assert_eq!("1:wCb3OG7yAFWelaUydu0D+125CLM=", id.unwrap());
    }

    #[test]
    fn test_tcp_without_ports() {
        let id = calculate_community_id(
            0,
            Ipv4Addr::new(1, 2, 3, 4).into(),
            Ipv4Addr::new(5, 6, 7, 8).into(),
            None,
            None,
            6,
            Default::default(),
        );
        assert!(id.is_err());
        assert_eq!(
            "src port and dst port should be set when protocol is tcp/udp/sctp",
            id.err().unwrap()
        );
    }
}