/// <summary>Validate received reply</summary>
/// <param name="packet">Received SNMP packet</param>
/// <returns>True if packet is validated, otherwise false</returns>
public bool ValidateReceivedPacket(SnmpPacket packet)
{
if (packet.Version != version)
{
return(false);
}
if (version == ESnmpVersion.Ver1)
{
SnmpV1Packet pkt = packet as SnmpV1Packet;
if (pkt.Community.Equals(community))
{
return(true);
}
}
if (version == ESnmpVersion.Ver2)
{
SnmpV2Packet pkt = packet as SnmpV2Packet;
if (pkt.Community.Equals(community))
{
return(true);
}
}
return(false);
}
/// <summary>
/// Initialize SNMP packet class with agent parameters. In this class, SNMP community name is
/// set in SNMPv1 and SNMPv2 packets.
/// </summary>
/// <param name="packet">Packet class to initialize</param>
public void InitializePacket(SnmpPacket packet)
{
if (packet is SnmpV1Packet)
{
SnmpV1Packet pkt = (SnmpV1Packet)packet;
pkt.Community.Set(_community);
}
else if (packet is SnmpV2Packet)
{
SnmpV2Packet pkt = (SnmpV2Packet)packet;
pkt.Community.Set(_community);
}
else
{
throw new SnmpInvalidVersionException("Invalid SNMP version.");
}
}
/// <summary>
/// Prepare packet for transmission by filling target specific information in the packet.
/// </summary>
/// <param name="packet">SNMP packet class for the required version</param>
/// <returns>True if packet values are correctly set, otherwise false.</returns>
public bool PreparePacketForTransmission(SnmpPacket packet)
{
if (packet.Version != _version)
{
return(false);
}
if (_version == SnmpVersion.Ver1)
{
SnmpV1Packet pkt = (SnmpV1Packet)packet;
pkt.Community.Set(_community);
return(true);
}
else if (_version == SnmpVersion.Ver2)
{
SnmpV2Packet pkt = (SnmpV2Packet)packet;
pkt.Community.Set(_community);
return(true);
}
return(false);
}
/// <summary>Prepare packet for transmission by filling target specific information in the packet.</summary>
/// <param name="packet">SNMP packet class for the required version</param>
/// <returns>True if packet values are correctly set, otherwise false.</returns>
public bool PreparePacketForTransmission(SnmpPacket packet)
{
if (packet.Version != version)
{
return(false);
}
if (version == ESnmpVersion.Ver1)
{
SnmpV1Packet pkt = packet as SnmpV1Packet;
pkt.Community.Set(community);
return(true);
}
if (version == ESnmpVersion.Ver2)
{
SnmpV2Packet pkt = packet as SnmpV2Packet;
pkt.Community.Set(community);
return(true);
}
return(false);
}
/// <summary>
/// Validate received reply
/// </summary>
/// <param name="packet">Received SNMP packet</param>
/// <returns>True if packet is validated, otherwise false</returns>
public bool ValidateReceivedPacket(SnmpPacket packet)
{
if (packet.Version != _version)
{
return(false);
}
if (_version == SnmpVersion.Ver1)
{
SnmpV1Packet pkt = (SnmpV1Packet)packet;
if (pkt.Community.Equals(_community))
{
return(true);
}
}
else if (_version == SnmpVersion.Ver2)
{
SnmpV2Packet pkt = (SnmpV2Packet)packet;
if (pkt.Community.Equals(_community))
{
return(true);
}
}
return(false);
}
/// <summary>
/// Thread Functions which does all the SNMP Agent job
/// </summary>
public void ListenerThread() {
mSock = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
mSock.ReceiveTimeout = 2000;
IPEndPoint vEndPoint = new IPEndPoint(IPAddress.Any, 16100);
mSock.Bind(vEndPoint);
Debug.Log ("Agent: thread started");
byte[] vBuff = new byte[4096];
int vLen = 0;
while (true) {
if (this.mSock.Available > 0) {
EndPoint vSender = (EndPoint)new IPEndPoint(IPAddress.Any, 0);
vLen = mSock.ReceiveFrom(vBuff, ref vSender);
//Debug.Log ("Agent: Data received (bytes): " + vLen);
SnmpPacket vPacket = new SnmpV1Packet("" + "public");
vPacket.decode(vBuff, vLen);
//Debug.Log("Agent: PDU decoded: " + vPacket.Pdu.VbCount);
Oid vOid = null;
responsePacket = new SnmpV1Packet("" + "public");
responsePacket.Pdu.ErrorStatus = 0; // no error
if (vPacket.Pdu != null && vPacket.Pdu.VbList != null) {
foreach (Vb vVb in vPacket.Pdu.VbList) {
Debug.Log(vVb.ToString());
vOid = vVb.Oid;
if (vPacket.Pdu.Type == PduType.Set)
ProcessSetRequest(vOid,vVb);
if (vPacket.Pdu.Type == PduType.GetNext){
GetNext(vOid);
break;
}
ProcessGetRequest(vOid);
}
}
//Debug.Log(vOid.ToString());
responsePacket.Pdu.Type = PduType.Response;
responsePacket.Pdu.RequestId = vPacket.Pdu.RequestId;
byte[] vOutBuff = responsePacket.encode();
mSock.SendTo(vOutBuff, vSender);
callPrint = true;
}
Thread.Sleep(1000);
}
}
internal void AsyncResponse(AsyncRequestResult result, IPEndPoint peer, byte[] buffer, int buflen)
{
if (result != AsyncRequestResult.NoError)
{
_response(result, null);
}
else
{
if (buffer == null || buffer.Length <= 0 || buflen <= 0)
{
_response(AsyncRequestResult.NoDataReceived, null);
return;
}
// verify packet
if (_agentParameters.Version == (int)SnmpVersion.Ver1)
{
SnmpV1Packet packet = new SnmpV1Packet();
try
{
packet.decode(buffer, buflen);
}
catch (Exception ex)
{
ex.GetType();
// Console.WriteLine("Exception while decoding SNMP packet: " + ex.ToString());
_response(AsyncRequestResult.DecodeError, packet);
return;
}
_response(AsyncRequestResult.NoError, packet);
return;
}
else if (_agentParameters.Version == SnmpVersion.Ver2)
{
SnmpV2Packet packet = new SnmpV2Packet();
try
{
packet.decode(buffer, buflen);
}
catch (Exception ex)
{
ex.GetType();
// Console.WriteLine("Exception while decoding SNMP packet: " + ex.ToString());
// MutableByte b = new MutableByte(buffer, buflen);
// Console.WriteLine("Buffer length {0}", buflen);
// SnmpConstants.DumpHex(b);
_response(AsyncRequestResult.DecodeError, packet);
return;
}
_response(AsyncRequestResult.NoError, packet);
}
else if (_agentParameters.Version == SnmpVersion.Ver3)
{
SnmpV3Packet packet = new SnmpV3Packet();
SecureAgentParameters secparams = (SecureAgentParameters)_agentParameters;
secparams.InitializePacket(packet);
try {
if (secparams.HasCachedKeys)
{
packet.decode(buffer, buflen, secparams.AuthenticationKey, secparams.PrivacyKey);
}
else
{
packet.decode(buffer, buflen);
}
}
catch
{
_response(AsyncRequestResult.DecodeError, packet);
return;
}
if (!secparams.ValidateIncomingPacket(packet))
{
_response(AsyncRequestResult.AuthenticationError, packet);
}
else
{
secparams.UpdateDiscoveryValues(packet); // update time, etc. values
_response(AsyncRequestResult.NoError, packet);
}
}
}
}
/// <summary>
/// Make SNMP request. With this method you can make blocked SNMP version 1, 2 and 3 requests of type GET,
/// GET-NEXT, GET-BULK, SET and REPORT (request types have to compatible with the SNMP protocol version you
/// are using).
///
/// This method will pass through any exceptions thrown by parsing classes/methods so see individual packet
/// classes, ASN.1 type classes, authentication, privacy, etc. classes for exceptions thrown.
/// </summary>
/// <param name="pdu">Pdu class (do not pass ScopedPdu)</param>
/// <param name="agentParameters">Security information for the request. Use <see cref="AgentParameters"/>
/// for SNMP versions 1 and 2 requests. Use <see cref="SecureAgentParameters"/> for SNMP version 3
/// requests.</param>
/// <param name="responseCallback">Callback that receives the result of the async operation.</param>
/// <returns>True if async request was successfully initiated, otherwise false.</returns>
public bool RequestAsync(Pdu pdu, IAgentParameters agentParameters, SnmpAsyncResponse responseCallback)
{
if (IsBusy)
{
return(false); // class is busy
}
_response = null;
_response += responseCallback;
_agentParameters = agentParameters;
byte[] outPacket;
if (agentParameters.Version == SnmpVersion.Ver3)
{
SecureAgentParameters secparams = (SecureAgentParameters)agentParameters;
if (secparams.Authentication != AuthenticationDigests.None && secparams.AuthenticationSecret.Length <= 0)
{
// _response(AsyncRequestResult.AuthenticationError, null);
return(false);
}
if (secparams.Privacy != PrivacyProtocols.None && secparams.PrivacySecret.Length <= 0)
{
// _response(AsyncRequestResult.PrivacyError, null);
return(false);
}
_noSourceCheck = false; // this option is not valid for SNMP v3 requests
ScopedPdu outPdu = new ScopedPdu(pdu);
outPdu.ContextEngineId.Set(secparams.EngineId);
outPdu.ContextName.Set(secparams.ContextName);
SnmpV3Packet packet = new SnmpV3Packet(outPdu);
secparams.InitializePacket(packet);
try
{
if (secparams.HasCachedKeys)
{
outPacket = packet.encode(secparams.AuthenticationKey, secparams.PrivacyKey);
}
else
{
outPacket = packet.encode();
}
}
catch (Exception ex)
{
ex.GetType();
_response(AsyncRequestResult.EncodeError, packet);
return(false);
}
}
else if (agentParameters.Version == (int)SnmpVersion.Ver1)
{
AgentParameters param = (AgentParameters)agentParameters;
_noSourceCheck = param.DisableReplySourceCheck;
SnmpV1Packet packet = new SnmpV1Packet();
packet.Pdu.Set(pdu);
packet.Community.Set(param.Community);
try
{
outPacket = packet.encode();
}
catch (Exception ex)
{
ex.GetType();
_response(AsyncRequestResult.EncodeError, packet);
return(false);
}
}
else if (agentParameters.Version == SnmpVersion.Ver2)
{
AgentParameters param = (AgentParameters)agentParameters;
_noSourceCheck = param.DisableReplySourceCheck;
SnmpV2Packet packet = new SnmpV2Packet();
packet.Pdu.Set(pdu);
packet.Community.Set(param.Community);
try
{
outPacket = packet.encode();
}
catch (Exception ex)
{
ex.GetType();
_response(AsyncRequestResult.EncodeError, packet);
return(false);
}
}
else
{
throw new SnmpInvalidVersionException("Unsupported SNMP version.");
}
if (!base.RequestAsync(_address, _port, outPacket, outPacket.Length, _timeout, _retry, new SnmpAsyncCallback(AsyncResponse)))
{
return(false);
}
return(true);
}
/// <summary>Make SNMP Request</summary>
/// <remarks>
/// Make SNMP request. With this method you can make blocked SNMP version 1, 2 and 3 requests of type GET,
/// GET-NEXT, GET-BULK, SET and REPORT (request types have to compatible with the SNMP protocol version you
/// are using).
///
/// This method will pass through any exceptions thrown by parsing classes/methods so see individual packet
/// classes, ASN.1 type classes, authentication, privacy, etc. classes for exceptions thrown.
/// </remarks>
/// <param name="pdu">Pdu class (do not pass ScopedPdu)</param>
/// <param name="agentParameters">Security information for the request. Use <see cref="AgentParameters"/>
/// for SNMP versions 1 and 2 requests. Use <see cref="SecureAgentParameters"/> for SNMP version 3
/// requests.</param>
/// <returns>Appropriate SNMP packet class for the reply received (<see cref="SnmpV1Packet"/>,
/// <see cref="SnmpV2Packet"/>, or <see cref="SnmpV3Packet"/>. Null value if there was an error
/// with the request.</returns>
/// <exception cref="SnmpAuthenticationException">Thrown on SNMPv3 requests when authentication password
/// is not specified on authNoPriv or authPriv requests in SecureAgentParameters or if incoming packet
/// authentication check failed.
///
/// With SNMP ver1 and ver2c, authentication check fails when invalid community name is parsed in the reply.</exception>
/// <exception cref="SnmpPrivacyException">Thrown on SNMPv3 requests when privacy password is not
/// specified in SecureAgentParameters on authPriv requests.</exception>
/// <exception cref="SnmpException">Thrown in following cases:
///
/// * IAgentParameters.Valid() returned false. SnmpException.ErrorCode is set to SnmpException.InvalidIAgentParameters
/// * No data received on request. SnmpException.ErrorCode is set to SnmpException.NoDataReceived
/// * Invalid RequestId in reply. SnmpException.ErrorCode is set to SnmpException.InvalidRequestId
/// </exception>
public SnmpPacket Request(Pdu pdu, IAgentParameters agentParameters)
{
byte[] outPacket;
if (agentParameters.Version == SnmpVersion.Ver3)
{
SecureAgentParameters secparams = (SecureAgentParameters)agentParameters;
if (secparams.Authentication != AuthenticationDigests.None && secparams.AuthenticationSecret.Length <= 0)
{
throw new SnmpAuthenticationException("Authentication password not specified.");
}
if (secparams.Privacy != PrivacyProtocols.None && secparams.PrivacySecret.Length <= 0)
{
throw new SnmpPrivacyException("Privacy password not specified.");
}
_noSourceCheck = false; // this option is not valid for SNMP v3 requests
ScopedPdu outPdu = new ScopedPdu(pdu);
SnmpV3Packet packet = new SnmpV3Packet(outPdu);
secparams.InitializePacket(packet);
if (secparams.HasCachedKeys)
{
outPacket = packet.encode(secparams.AuthenticationKey, secparams.PrivacyKey);
}
else
{
outPacket = packet.encode();
}
}
else if (agentParameters.Version == SnmpVersion.Ver1)
{
AgentParameters param = (AgentParameters)agentParameters;
if (!param.Valid())
{
throw new SnmpException(SnmpException.InvalidIAgentParameters, "Invalid AgentParameters. Unable to process request.");
}
SnmpV1Packet packet = new SnmpV1Packet();
packet.Pdu.Set(pdu);
packet.Community.Set(param.Community);
outPacket = packet.encode();
_noSourceCheck = param.DisableReplySourceCheck;
}
else if (agentParameters.Version == SnmpVersion.Ver2)
{
AgentParameters param = (AgentParameters)agentParameters;
if (!param.Valid())
{
throw new SnmpException(SnmpException.InvalidIAgentParameters, "Invalid AgentParameters. Unable to process request.");
}
SnmpV2Packet packet = new SnmpV2Packet();
packet.Pdu.Set(pdu);
packet.Community.Set(param.Community);
_noSourceCheck = param.DisableReplySourceCheck;
outPacket = packet.encode();
}
else
{
throw new SnmpInvalidVersionException("Unsupported SNMP version.");
}
byte[] inBuffer = base.Request(_address, _port, outPacket, outPacket.Length, _timeout, _retry);
if (inBuffer == null || inBuffer.Length <= 0)
{
throw new SnmpException(SnmpException.NoDataReceived, "No data received on request.");
}
// verify packet
if (agentParameters.Version == SnmpVersion.Ver1)
{
SnmpV1Packet packet = new SnmpV1Packet();
AgentParameters param = (AgentParameters)agentParameters;
packet.decode(inBuffer, inBuffer.Length);
if (packet.Community != param.Community)
{
// invalid community name received. Ignore the rest of the packet
throw new SnmpAuthenticationException("Invalid community name in reply.");
}
if (packet.Pdu.RequestId != pdu.RequestId)
{
// invalid request id. unmatched response ignored
throw new SnmpException(SnmpException.InvalidRequestId, "Invalid request id in reply.");
}
return(packet);
}
else if (agentParameters.Version == SnmpVersion.Ver2)
{
SnmpV2Packet packet = new SnmpV2Packet();
AgentParameters param = (AgentParameters)agentParameters;
packet.decode(inBuffer, inBuffer.Length);
if (packet.Community != param.Community)
{
// invalid community name received. Ignore the rest of the packet
throw new SnmpAuthenticationException("Invalid community name in reply.");
}
if (packet.Pdu.RequestId != pdu.RequestId)
{
// invalid request id. unmatched response ignored
throw new SnmpException(SnmpException.InvalidRequestId, "Invalid request id in reply.");
}
return(packet);
}
else if (agentParameters.Version == SnmpVersion.Ver3)
{
SnmpV3Packet packet = new SnmpV3Packet();
SecureAgentParameters secparams = (SecureAgentParameters)agentParameters;
secparams.InitializePacket(packet);
if (secparams.HasCachedKeys)
{
packet.decode(inBuffer, inBuffer.Length, secparams.AuthenticationKey, secparams.PrivacyKey);
}
else
{
packet.decode(inBuffer, inBuffer.Length);
}
// first check if packet is a discovery response and process it
if (packet.Pdu.Type == PduType.Report && packet.Pdu.VbCount > 0 && packet.Pdu.VbList[0].Oid.Equals(SnmpConstants.usmStatsUnknownEngineIDs))
{
secparams.UpdateDiscoveryValues(packet);
return(packet);
}
else
{
if (!secparams.ValidateIncomingPacket(packet))
{
return(null);
}
else
{
secparams.UpdateDiscoveryValues(packet); // update time, etc. values
return(packet);
}
}
}
return(null);
}
private static bool WalkGetNext(IPAddress agent, string community, string oid, Func <Vb, bool> handleValue)
{
// SNMP community name
OctetString communityString = new OctetString(community);
// Define agent parameters class
AgentParameters param = new AgentParameters(communityString)
{
// Set SNMP version to 1
Version = SnmpVersion.Ver1
};
// Construct target
UdpTarget target = new UdpTarget(agent, 161, 2000, 1);
// Define Oid that is the root of the MIB
// tree you wish to retrieve
Oid rootOid = new Oid(oid); // ifDescr
// This Oid represents last Oid returned by
// the SNMP agent
Oid lastOid = (Oid)rootOid.Clone();
// Pdu class used for all requests
Pdu pdu = new Pdu(PduType.GetNext);
// Loop through results
while (lastOid != null)
{
// When Pdu class is first constructed, RequestId is set to a random value
// that needs to be incremented on subsequent requests made using the
// same instance of the Pdu class.
if (pdu.RequestId != 0)
{
pdu.RequestId += 1;
}
// Clear Oids from the Pdu class.
pdu.VbList.Clear();
// Initialize request PDU with the last retrieved Oid
pdu.VbList.Add(lastOid);
// Make SNMP request
SnmpV1Packet result = (SnmpV1Packet)target.Request(pdu, param);
// You should catch exceptions in the Request if using in real application.
// If result is null then agent didn't reply or we couldn't parse the reply.
if (result != null)
{
// ErrorStatus other then 0 is an error returned by
// the Agent - see SnmpConstants for error definitions
if (result.Pdu.ErrorStatus != 0)
{
// agent reported an error with the request
//System.Diagnostics.Debug.WriteLine("Error in SNMP reply. Error {0} index {1}",
// result.Pdu.ErrorStatus,
// result.Pdu.ErrorIndex);
lastOid = null;
break;
}
else
{
// Walk through returned variable bindings
foreach (Vb v in result.Pdu.VbList)
{
// Check that retrieved Oid is "child" of the root OID
if (rootOid.IsRootOf(v.Oid))
{
//System.Diagnostics.Debug.WriteLine("{0} ({1}): {2}",
// v.Oid.ToString(),
// SnmpConstants.GetTypeName(v.Value.Type),
// v.Value.ToString());
handleValue(v);
lastOid = v.Oid;
}
else
{
// we have reached the end of the requested
// MIB tree. Set lastOid to null and exit loop
lastOid = null;
}
}
}
}
else
{
//System.Diagnostics.Debug.WriteLine("No response received from SNMP agent.");
}
}
target.Close();
return(true);
}
/// <summary>
/// Prints the packets
/// </summary>
/// <param name="result"></param>
public void PrintPacketRecv(SnmpV1Packet result)
{
// ErrorStatus other then 0 is an error returned by
// the Agent - see SnmpConstants for error definitions
if (result.Pdu.Type == PduType.Set)
{
PacketPrinterRcv.text = "Set ";
}
if (result.Pdu.Type == PduType.Get)
{
PacketPrinterRcv.text = "Get ";
}
if (result.Pdu.ErrorStatus != 0)
{
// agent reported an error with the request
PacketPrinterRcv.text = "Error: status " + result.Pdu.ErrorStatus + " Index " + result.Pdu.ErrorIndex;
}
else
{
// Reply variables are returned in the same order as they were added
// to the VbList
foreach (Vb VarBind in result.Pdu.VbList)
{
PacketPrinterRcv.text = "Request OID: " + VarBind.Oid.ToString() + " Type " + SnmpConstants.GetTypeName(VarBind.Value.Type) + " Value " + VarBind.Value.ToString();
}
}
}
internal void AsyncResponse(AsyncRequestResult result, IPEndPoint peer, byte[] buffer, int buflen)
{
if (result != AsyncRequestResult.NoError)
{
_response(result, null);
}
else
{
if (buffer == null || buffer.Length <= 0 || buflen <= 0)
{
_response(AsyncRequestResult.NoDataReceived, null);
return;
}
// verify packet
if (_agentParameters.Version == (int)SnmpVersion.Ver1)
{
SnmpV1Packet packet = new SnmpV1Packet();
try
{
packet.decode(buffer, buflen);
}
catch(Exception ex)
{
ex.GetType();
// Console.WriteLine("Exception while decoding SNMP packet: " + ex.ToString());
_response(AsyncRequestResult.DecodeError, packet);
return;
}
_response(AsyncRequestResult.NoError, packet);
return;
}
else if (_agentParameters.Version == SnmpVersion.Ver2)
{
SnmpV2Packet packet = new SnmpV2Packet();
try
{
packet.decode(buffer, buflen);
}
catch (Exception ex)
{
ex.GetType();
// Console.WriteLine("Exception while decoding SNMP packet: " + ex.ToString());
// MutableByte b = new MutableByte(buffer, buflen);
// Console.WriteLine("Buffer length {0}", buflen);
// SnmpConstants.DumpHex(b);
_response(AsyncRequestResult.DecodeError, packet);
return;
}
_response(AsyncRequestResult.NoError, packet);
}
else if (_agentParameters.Version == SnmpVersion.Ver3)
{
SnmpV3Packet packet = new SnmpV3Packet();
SecureAgentParameters secparams = (SecureAgentParameters)_agentParameters;
secparams.InitializePacket(packet);
try {
if (secparams.HasCachedKeys)
packet.decode(buffer, buflen, secparams.AuthenticationKey, secparams.PrivacyKey);
else
packet.decode(buffer, buflen);
}
catch
{
_response(AsyncRequestResult.DecodeError, packet);
return;
}
if (!secparams.ValidateIncomingPacket(packet))
{
_response(AsyncRequestResult.AuthenticationError, packet);
}
else
{
secparams.UpdateDiscoveryValues(packet); // update time, etc. values
_response(AsyncRequestResult.NoError, packet);
}
}
}
}
/// <summary>
/// Make SNMP request. With this method you can make blocked SNMP version 1, 2 and 3 requests of type GET,
/// GET-NEXT, GET-BULK, SET and REPORT (request types have to compatible with the SNMP protocol version you
/// are using).
///
/// This method will pass through any exceptions thrown by parsing classes/methods so see individual packet
/// classes, ASN.1 type classes, authentication, privacy, etc. classes for exceptions thrown.
/// </summary>
/// <param name="pdu">Pdu class (do not pass ScopedPdu)</param>
/// <param name="agentParameters">Security information for the request. Use <see cref="AgentParameters"/>
/// for SNMP versions 1 and 2 requests. Use <see cref="SecureAgentParameters"/> for SNMP version 3
/// requests.</param>
/// <param name="responseCallback">Callback that receives the result of the async operation.</param>
/// <returns>True if async request was successfully initiated, otherwise false.</returns>
public bool RequestAsync(Pdu pdu, IAgentParameters agentParameters, SnmpAsyncResponse responseCallback)
{
if (IsBusy)
{
return false; // class is busy
}
_response = null;
_response += responseCallback;
_agentParameters = agentParameters;
byte[] outPacket;
if (agentParameters.Version == SnmpVersion.Ver3)
{
SecureAgentParameters secparams = (SecureAgentParameters)agentParameters;
if (secparams.Authentication != AuthenticationDigests.None && secparams.AuthenticationSecret.Length <= 0)
{
// _response(AsyncRequestResult.AuthenticationError, null);
return false;
}
if (secparams.Privacy != PrivacyProtocols.None && secparams.PrivacySecret.Length <= 0)
{
// _response(AsyncRequestResult.PrivacyError, null);
return false;
}
_noSourceCheck = false; // this option is not valid for SNMP v3 requests
ScopedPdu outPdu = new ScopedPdu(pdu);
outPdu.ContextEngineId.Set(secparams.EngineId);
outPdu.ContextName.Set(secparams.ContextName);
SnmpV3Packet packet = new SnmpV3Packet(outPdu);
secparams.InitializePacket(packet);
try
{
if (secparams.HasCachedKeys)
outPacket = packet.encode(secparams.AuthenticationKey, secparams.PrivacyKey);
else
outPacket = packet.encode();
}
catch( Exception ex )
{
ex.GetType();
_response(AsyncRequestResult.EncodeError, packet);
return false;
}
}
else if (agentParameters.Version == (int)SnmpVersion.Ver1)
{
AgentParameters param = (AgentParameters)agentParameters;
_noSourceCheck = param.DisableReplySourceCheck;
SnmpV1Packet packet = new SnmpV1Packet();
packet.Pdu.Set(pdu);
packet.Community.Set(param.Community);
try
{
outPacket = packet.encode();
}
catch( Exception ex)
{
ex.GetType();
_response(AsyncRequestResult.EncodeError, packet);
return false;
}
}
else if (agentParameters.Version == SnmpVersion.Ver2)
{
AgentParameters param = (AgentParameters)agentParameters;
_noSourceCheck = param.DisableReplySourceCheck;
SnmpV2Packet packet = new SnmpV2Packet();
packet.Pdu.Set(pdu);
packet.Community.Set(param.Community);
try
{
outPacket = packet.encode();
}
catch( Exception ex )
{
ex.GetType();
_response(AsyncRequestResult.EncodeError, packet);
return false;
}
}
else
{
throw new SnmpInvalidVersionException("Unsupported SNMP version.");
}
if( ! base.RequestAsync(_address, _port, outPacket, outPacket.Length, _timeout, _retry, new SnmpAsyncCallback(AsyncResponse) ) ) {
return false;
}
return true;
}
/// <summary>Make SNMP Request</summary>
/// <remarks>
/// Make SNMP request. With this method you can make blocked SNMP version 1, 2 and 3 requests of type GET,
/// GET-NEXT, GET-BULK, SET and REPORT (request types have to compatible with the SNMP protocol version you
/// are using).
///
/// This method will pass through any exceptions thrown by parsing classes/methods so see individual packet
/// classes, ASN.1 type classes, authentication, privacy, etc. classes for exceptions thrown.
/// </remarks>
/// <param name="pdu">Pdu class (do not pass ScopedPdu)</param>
/// <param name="agentParameters">Security information for the request. Use <see cref="AgentParameters"/>
/// for SNMP versions 1 and 2 requests. Use <see cref="SecureAgentParameters"/> for SNMP version 3
/// requests.</param>
/// <returns>Appropriate SNMP packet class for the reply received (<see cref="SnmpV1Packet"/>,
/// <see cref="SnmpV2Packet"/>, or <see cref="SnmpV3Packet"/>. Null value if there was an error
/// with the request.</returns>
/// <exception cref="SnmpAuthenticationException">Thrown on SNMPv3 requests when authentication password
/// is not specified on authNoPriv or authPriv requests in SecureAgentParameters or if incoming packet
/// authentication check failed.
///
/// With SNMP ver1 and ver2c, authentication check fails when invalid community name is parsed in the reply.</exception>
/// <exception cref="SnmpPrivacyException">Thrown on SNMPv3 requests when privacy password is not
/// specified in SecureAgentParameters on authPriv requests.</exception>
/// <exception cref="SnmpException">Thrown in following cases:
///
/// * IAgentParameters.Valid() returned false. SnmpException.ErrorCode is set to SnmpException.InvalidIAgentParameters
/// * No data received on request. SnmpException.ErrorCode is set to SnmpException.NoDataReceived
/// * Invalid RequestId in reply. SnmpException.ErrorCode is set to SnmpException.InvalidRequestId
/// </exception>
public SnmpPacket Request(Pdu pdu, IAgentParameters agentParameters)
{
byte[] outPacket;
if (agentParameters.Version == SnmpVersion.Ver3)
{
SecureAgentParameters secparams = (SecureAgentParameters)agentParameters;
if (secparams.Authentication != AuthenticationDigests.None && secparams.AuthenticationSecret.Length <= 0)
throw new SnmpAuthenticationException("Authentication password not specified.");
if (secparams.Privacy != PrivacyProtocols.None && secparams.PrivacySecret.Length <= 0)
throw new SnmpPrivacyException("Privacy password not specified.");
_noSourceCheck = false; // this option is not valid for SNMP v3 requests
ScopedPdu outPdu = new ScopedPdu(pdu);
SnmpV3Packet packet = new SnmpV3Packet(outPdu);
secparams.InitializePacket(packet);
if (secparams.HasCachedKeys)
outPacket = packet.encode(secparams.AuthenticationKey, secparams.PrivacyKey);
else
outPacket = packet.encode();
}
else if (agentParameters.Version == SnmpVersion.Ver1)
{
AgentParameters param = (AgentParameters)agentParameters;
if (!param.Valid())
throw new SnmpException(SnmpException.InvalidIAgentParameters,"Invalid AgentParameters. Unable to process request.");
SnmpV1Packet packet = new SnmpV1Packet();
packet.Pdu.Set(pdu);
packet.Community.Set(param.Community);
outPacket = packet.encode();
_noSourceCheck = param.DisableReplySourceCheck;
}
else if (agentParameters.Version == SnmpVersion.Ver2)
{
AgentParameters param = (AgentParameters)agentParameters;
if (!param.Valid())
throw new SnmpException(SnmpException.InvalidIAgentParameters, "Invalid AgentParameters. Unable to process request.");
SnmpV2Packet packet = new SnmpV2Packet();
packet.Pdu.Set(pdu);
packet.Community.Set(param.Community);
_noSourceCheck = param.DisableReplySourceCheck;
outPacket = packet.encode();
}
else
{
throw new SnmpInvalidVersionException("Unsupported SNMP version.");
}
byte[] inBuffer = base.Request(_address, _port, outPacket, outPacket.Length, _timeout, _retry);
if (inBuffer == null || inBuffer.Length <= 0)
{
return null;
}
// verify packet
if (agentParameters.Version == SnmpVersion.Ver1)
{
SnmpV1Packet packet = new SnmpV1Packet();
AgentParameters param = (AgentParameters)agentParameters;
packet.decode(inBuffer, inBuffer.Length);
if (packet.Community != param.Community)
{
// invalid community name received. Ignore the rest of the packet
throw new SnmpAuthenticationException("Invalid community name in reply.");
}
if (packet.Pdu.RequestId != pdu.RequestId)
{
// invalid request id. unmatched response ignored
throw new SnmpException(SnmpException.InvalidRequestId, "Invalid request id in reply.");
}
return packet;
}
else if (agentParameters.Version == SnmpVersion.Ver2)
{
SnmpV2Packet packet = new SnmpV2Packet();
AgentParameters param = (AgentParameters)agentParameters;
packet.decode(inBuffer, inBuffer.Length);
if (packet.Community != param.Community)
{
// invalid community name received. Ignore the rest of the packet
throw new SnmpAuthenticationException("Invalid community name in reply.");
}
if (packet.Pdu.RequestId != pdu.RequestId)
{
// invalid request id. unmatched response ignored
throw new SnmpException(SnmpException.InvalidRequestId, "Invalid request id in reply.");
}
return packet;
}
else if (agentParameters.Version == SnmpVersion.Ver3)
{
SnmpV3Packet packet = new SnmpV3Packet();
SecureAgentParameters secparams = (SecureAgentParameters)agentParameters;
secparams.InitializePacket(packet);
if (secparams.HasCachedKeys)
packet.decode(inBuffer, inBuffer.Length, secparams.AuthenticationKey, secparams.PrivacyKey);
else
packet.decode(inBuffer, inBuffer.Length);
// first check if packet is a discovery response and process it
if (packet.Pdu.Type == PduType.Report && packet.Pdu.VbCount > 0 && packet.Pdu.VbList[0].Oid.Equals(SnmpConstants.usmStatsUnknownEngineIDs))
{
secparams.UpdateDiscoveryValues(packet);
return packet;
}
else
{
if (!secparams.ValidateIncomingPacket(packet))
{
return null;
}
else
{
secparams.UpdateDiscoveryValues(packet); // update time, etc. values
return packet;
}
}
}
return null;
}
