[Rust] - SNMPを使って指定IPの機器から複数のOIDをGET/WALKする

main.rs

use encoding_rs::SHIFT_JIS;
use snmp::{SyncSession, Value};
use std::{error::Error, net::ToSocketAddrs, time::Duration};

fn main() -> Result<(), Box<dyn Error>> {
    let target = "10.200.32.27:161".to_socket_addrs()?.next().unwrap();
    let community = b"public";
    let mut session = SyncSession::new(target, community, Some(Duration::from_secs(2)), 0)?;

    let oid_get_list: Vec<Vec<u32>> = vec![
        vec![1, 3, 6, 1, 2, 1, 25, 3, 5, 1, 1, 1],     // hrPrinterStatus
        vec![1, 3, 6, 1, 2, 1, 25, 3, 2, 1, 5, 1],     // hrDeviceStatus
        vec![1, 3, 6, 1, 2, 1, 43, 10, 2, 1, 4, 1, 1], // prtMarkerLifeCount
    ];

    let oid_walks: Vec<Vec<u32>> = vec![
        vec![1, 3, 6, 1, 2, 1, 43, 11, 1, 1, 9, 1],
        vec![1, 3, 6, 1, 2, 1, 43, 8, 2, 1, 10, 1],
        vec![1, 3, 6, 1, 2, 1, 43, 11, 1, 1, 6, 1],
        vec![1, 3, 6, 1, 2, 1, 43, 11, 1, 1, 8, 1],
        vec![1, 3, 6, 1, 2, 1, 43, 8, 2, 1, 4, 1],
        vec![1, 3, 6, 1, 2, 1, 43, 16, 5, 1, 2, 1],
        vec![1, 3, 6, 1, 2, 1, 43, 8, 2, 1, 9, 1],
        vec![1, 3, 6, 1, 2, 1, 43, 18, 1, 1, 8, 1],
    ];

    println!("=== SNMP GET ===");

    for oid in oid_get_list.iter() {
        match session.get(&oid) {
            Ok(pdu) => {
                let mut varbinds = pdu.varbinds;
                if let Some((oid, val)) = varbinds.next() {
                    match val {
                        Value::Integer(v) => println!("  {:?}: {}", oid, v),
                        Value::OctetString(bytes) => {
                            // Try UTF-8 first
                            match String::from_utf8(bytes.to_vec()) {
                                Ok(utf8_str) => println!("  {:?}: {}", oid, utf8_str),
                                Err(_) => {
                                    // Fallback: Shift_JIS
                                    let (cow, _, _) = SHIFT_JIS.decode(&bytes);
                                    println!("  {:?}: {}", oid, cow);
                                }
                            }
                        }
                        v => println!("  {:?}: {:?}", oid, v),
                    }
                } else {
                    println!("No response (empty varbind) for OID: {:?}", oid);
                }
            }
            Err(e) => {
                eprintln!("Error during SNMP get for {:?}: {:?}", oid, e);
            }
        }
    }

    println!("=== SNMP WALK (manual via getnext) ===");

    for base_oid in oid_walks.iter() {
        let mut current_oid = base_oid.clone();

        loop {
            let pdu = match session.getnext(&current_oid) {
                Ok(pdu) => pdu,
                Err(e) => {
                    eprintln!("Error during SNMP getnext: {:?}", e);
                    break;
                }
            };
            if let Some((oid, val)) = pdu.varbinds.into_iter().next() {
                let mut buf = [0u32; 128];
                let oid_vec = match oid.read_name(&mut buf) {
                    Ok(slice) => slice.to_vec(),
                    Err(e) => {
                        eprintln!("Failed to decode OID: {:?}", e);
                        break;
                    }
                };

                if !oid_vec.starts_with(base_oid) {
                    break;
                }

                match val {
                    Value::Integer(v) => println!("  {:?}: {}", oid, v),
                    Value::OctetString(bytes) => {
                        match String::from_utf8(bytes.to_vec()) {
                            Ok(utf8_str) => println!("  {:?}: {}", oid, utf8_str),
                            Err(_) => {
                                let (cow, _, _) = SHIFT_JIS.decode(&bytes);
                                println!("  {:?}: {}", oid, cow);
                            }
                        }
                    }
                    v => println!("  {:?}: {:?}", oid, v),
                }

                current_oid = oid_vec;
            }
        }
    }

    Ok(())
}