/// <summary>
/// SNMP GET request
/// </summary>
/// <example>SNMP GET request:
/// <code>
/// String snmpAgent = "10.10.10.1";
/// String snmpCommunity = "public";
/// SimpleSnmp snmp = new SimpleSnmp(snmpAgent, snmpCommunity);
/// // Create a request Pdu
/// Pdu pdu = new Pdu();
/// pdu.Type = SnmpConstants.GET; // type GET
/// pdu.VbList.Add("1.3.6.1.2.1.1.1.0");
/// Dictionary<Oid, AsnType> result = snmp.GetNext(SnmpVersion.Ver1, pdu);
/// if( result == null ) {
/// Console.WriteLine("Request failed.");
/// } else {
/// foreach (KeyValuePair<Oid, AsnType> entry in result)
/// {
/// Console.WriteLine("{0} = {1}: {2}", entry.Key.ToString(), SnmpConstants.GetTypeName(entry.Value.Type),
/// entry.Value.ToString());
/// }
/// }
/// </code>
/// Will return:
/// <code>
/// 1.3.6.1.2.1.1.1.0 = OctetString: "Dual core Intel notebook"
/// </code>
/// </example>
/// <param name="version">SNMP protocol version. Acceptable values are SnmpVersion.Ver1 and SnmpVersion.Ver2</param>
/// <param name="pdu">Request Protocol Data Unit</param>
/// <returns>Result of the SNMP request in a dictionary format with Oid => AsnType values</returns>
public Dictionary <Oid, AsnType> Get(SnmpVersion version, Pdu pdu)
{
if (!Valid)
{
if (!_suppressExceptions)
{
throw new SnmpException("SimpleSnmp class is not valid.");
}
return(null); // class is not fully initialized.
}
// function only works on SNMP version 1 and SNMP version 2 requests
if (version != SnmpVersion.Ver1 && version != SnmpVersion.Ver2)
{
if (!_suppressExceptions)
{
throw new SnmpInvalidVersionException("SimpleSnmp support SNMP version 1 and 2 only.");
}
return(null);
}
try
{
_target = new UdpTarget(_peerIP, _peerPort, _timeout, _retry);
}
catch (Exception ex)
{
_target = null;
if (!_suppressExceptions)
{
throw ex;
}
}
if (_target == null)
{
return(null);
}
try
{
AgentParameters param = new AgentParameters(version, new OctetString(_community));
SnmpPacket result = _target.Request(pdu, param);
if (result != null)
{
if (result.Pdu.ErrorStatus == 0)
{
Dictionary <Oid, AsnType> res = new Dictionary <Oid, AsnType>();
foreach (Vb v in result.Pdu.VbList)
{
if (version == SnmpVersion.Ver2 && (v.Value.Type == SnmpConstants.SMI_NOSUCHINSTANCE ||
v.Value.Type == SnmpConstants.SMI_NOSUCHOBJECT))
{
if (!res.ContainsKey(v.Oid))
{
res.Add(v.Oid, new Null());
}
else
{
res.Add(Oid.NullOid(), v.Value);
}
}
else
{
if (!res.ContainsKey(v.Oid))
{
res.Add(v.Oid, v.Value);
}
else
{
if (res[v.Oid].Type == v.Value.Type)
{
res[v.Oid] = v.Value; // update value of the existing Oid entry
}
else
{
throw new SnmpException(SnmpException.OidValueTypeChanged, string.Format("Value type changed from {0} to {1}", res[v.Oid].Type, v.Value.Type));
}
}
}
}
_target.Close();
_target = null;
return(res);
}
else
{
if (!_suppressExceptions)
{
throw new SnmpErrorStatusException("Agent responded with an error", result.Pdu.ErrorStatus, result.Pdu.ErrorIndex);
}
}
}
}
catch (Exception ex)
{
if (!_suppressExceptions)
{
_target.Close();
_target = null;
throw ex;
}
}
_target.Close();
_target = null;
return(null);
}