snmputils.php

<?php
class snmp_querier {
    private $ip;
    private $community;
    private $type;
    private $version;
    
    function __construct($ip, $community, $version) {
        $this->ip = $ip;
        $this->community = $community;
        $this->version = $version;
    }

    function walk($oid) {
        // we're using realwalk so that we can build iterators with map_oids(), see:
        // walk     [0] => eth0
        // realwalk [IF-MIB::ifDescr.2] => eth0
        if($this->version == "1") {
            $snmp_result = snmprealwalk($this->ip, $this->community, $oid);
        } else if($this->version == "2c") {
            $snmp_result = snmp2_real_walk($this->ip, $this->community, $oid);
        }
        $result = $this->clear_snmp_string($snmp_result);
        return $result;
    }

    function get($oid) {
        if($this->version == "1") {
            $snmp_result = snmpget($this->ip, $this->community, $oid);
        } else if($this->version == "2c") {
            $snmp_result = snmp2_get($this->ip, $this->community, $oid);
        }
        $result = $this->clear_snmp_string($snmp_result);
        return $result;
    }

    function get_oids($query) {
        // this function builds iterators for snmp gets starting from a walk, e.g.
        // IF-MIB::ifDescr.1 and IF-MIB::ifDescr.3 --> [0] => 1, [1] => 3
        foreach($query as $oid=>$value) {
            $oid_split = explode(".", $oid);
            $oidlist[] = $oid_split[count($oid_split)-1];
        }
        return $oidlist;
    }

    function map_oids($query) {
        // this function maps the name to the last OID digit, e.g.:
        // [IF-MIB::ifDescr.1] => eth0, [IF-MIB::ifDescr.3] => eth1
        // [eth0] => 1, [eth1] => 3
        // just like get_oids() this turns useful for iterating over items
        // we're swapping keys with their values and doing some cleanup..
        $oidmap = array_flip($query);
        foreach($oidmap as $item=>&$oid) {
            $oid_split = explode(".", $oid);
            $oid = $oid_split[count($oid_split)-1];
        }
        return $oidmap;
    }

    function get_uptime_from_timeticks($str) {
        $re = "/Timeticks: \\((.*)\\) (.*)\\./";
        preg_match_all($re, $str, $matches);
        return $matches[2][0];
    }
    
    function clear_snmp_string($data) {
        // clean this all up (filter?)
        if(is_array($data)) {
            foreach($data as $key=>&$val) {
                $val = str_replace('STRING: ', '', $val);
                $val = str_replace('Counter32: ', '', $val);
                $val = str_replace('"', '', $val);
                $val = trim($val);
            }
        }
        else {
            $data = str_replace('STRING: ', '', $data);
            $data = str_replace('INTEGER: ', '', $data);
            $data = str_replace('Counter32: ', '', $data);
            $data = str_replace('"', '', $data);
            $data = trim($data);
        }
        return $data;
    }
}

?>