SNMPTCPAgent Component

Properties   Methods   Events   Config Settings   Errors  

The SNMPTCPAgent component is used to implement TCP-based SNMP Agent Applications.

Syntax

nsoftware.IPWorksSNMP.Snmptcpagent

Remarks

The SNMPTCPAgent component implements a TCP-based standard SNMP Agent as specified in the SNMP RFCs. The component supports SNMP v1, v2c, and v3.

The component provides both encoding/decoding and transport capabilities, making the task of developing a custom SNMP agent as simple as setting a few key properties and handling a few events. SNMP data such as SNMP object id-s (OID-s) are exchanged as text strings, thus further simplifying the task of handling them.

The component is activated/deactivated by calling the Activate or Deactivate method. These methods enable or disable sending and receiving. The activation status can be found in the Active property.

The component operates asynchronously. Requests are received through events such as GetRequest, GetBulkRequest, GetNextRequest, etc. and the corresponding responses are automatically sent when the events return. Traps are sent through the SendTrap method.

SNMPv3 USM security passwords are requested through the GetUserPassword event, and event parameters such as User and SecurityLevel provide information about the security attributes of received requests, and enable granular decision capability about what to provide and what not to provide. The SendSecureTrap method is used to send authenticated (secure) SNMPv3 traps.

The AddUser, RemoveUser, ShowCache, and ClearCache methods are used to manage an internal authentication cache. This internal cache can be used as an alternative to the GetUserPassword event, automatically checking the cache against the security parameters provided in the request signature.

SNMP OIDs, types, and values are provided in the Objects collection of SNMP objects for both sent and received packets.

Other packet information is provided through corresponding event parameters, such as Community, or RequestId.

Property List

The following is the full list of the properties of the component with short descriptions. Click on the links for further details.

Method List

The following is the full list of the methods of the component with short descriptions. Click on the links for further details.

Event List

The following is the full list of the events fired by the component with short descriptions. Click on the links for further details.

Config Settings

The following is a list of config settings for the component with short descriptions. Click on the links for further details.

AcceptData Property (SNMPTCPAgent Component)

Enables or disables data reception.

Syntax

• C#
• VB.NET

public bool AcceptData { get; set; }

Public Property AcceptData As Boolean

Default Value

True

Remarks

Setting the property to False temporarily disables data reception. Setting the property to True re-enables data reception.

This property is not available at design time.

Active Property (SNMPTCPAgent Component)

Indicates whether the component is active.

Syntax

• C#
• VB.NET

public bool Active { get; set; }

Public Property Active As Boolean

Default Value

False

Remarks

This property indicates whether the component is currently active and can send or receive data.

The component will be automatically activated if it is not already and you attempt to perform an operation which requires the component to be active.

Note: Use the Activate or Deactivate method to control whether the component is active.

This property is not available at design time.

LocalEngineId Property (SNMPTCPAgent Component)

The Engine Id of the SNMP Agent.

Syntax

• C#
• VB.NET

public string LocalEngineId { get; set; }
public byte[] LocalEngineIdB { get; set; }

Public Property LocalEngineId As String
Public Property LocalEngineIdB As Byte()

Default Value

""

Remarks

This property is only used for SNMPv3 packets (when SNMPVersion is 3).

LocalHost Property (SNMPTCPAgent Component)

The name of the local host or user-assigned IP interface through which connections are initiated or accepted.

Syntax

• C#
• VB.NET

public string LocalHost { get; set; }

Public Property LocalHost As String

Default Value

""

Remarks

The LocalHost property contains the name of the local host as obtained by the gethostname() system call, or if the user has assigned an IP address, the value of that address.

In multi-homed hosts (machines with more than one IP interface) setting LocalHost to the value of an interface will make the component initiate connections (or accept in the case of server components) only through that interface.

If the component is connected, the LocalHost property shows the IP address of the interface through which the connection is made in internet dotted format (aaa.bbb.ccc.ddd). In most cases, this is the address of the local host, except for multi-homed hosts (machines with more than one IP interface).

NOTE: LocalHost is not persistent. You must always set it in code, and never in the property window.

LocalPort Property (SNMPTCPAgent Component)

The port in the local host where the component listens.

Syntax

• C#
• VB.NET

public int LocalPort { get; set; }

Public Property LocalPort As Integer

Default Value

161

Remarks

The LocalPort property must be set before the component is activated (Active is set to True). It instructs the component to bind to a specific port (or communication endpoint) in the local machine (default 161).

You may also set LocalPort to 0. This allows the TCP/IP stack to choose a port at random. The value chosen is provided via the LocalPort property after the component is activated through the Active property.

LocalPort cannot be changed once the component is Active. Any attempt to set the LocalPort property when the component is Active will generate an error.

Note: on macOS and iOS, root permissions are required to set LocalPort to any value below 1024.

Objects Property (SNMPTCPAgent Component)

The objects in the current request.

Syntax

• C#
• VB.NET

public SNMPObjectList Objects { get; }

Public Property Objects As SNMPObjectList

Remarks

The SNMP objects being sent or received in the current request. The collection is first cleared, then populated every time an SNMP packet is received. It is also used to create outgoing SNMP packets.

This collection is indexed from 0 to count -1.

RequestId Property (SNMPTCPAgent Component)

The request-id to mark outgoing packets with.

Syntax

• C#
• VB.NET

public int RequestId { get; set; }

Public Property RequestId As Integer

Default Value

1

Remarks

If a custom value is needed for RequestId, the property must be set before sending the request. The component increments RequestId automatically after sending each packet.

This property is not available at design time.

SNMPVersion Property (SNMPTCPAgent Component)

Version of SNMP used for outgoing requests (traps).

Syntax

• C#
• VB.NET

public SnmptcpagentSNMPVersions SNMPVersion { get; set; }

enum SnmptcpagentSNMPVersions {
  snmpverV1,
  snmpverV2c,
  snmpverV3
}

Public Property SNMPVersion As SnmptcpagentSNMPVersions

Enum SnmptcpagentSNMPVersions
  snmpverV1
  snmpverV2c
  snmpverV3
End Enum

Default Value

2

Remarks

This property takes one of the following values:

SSLAcceptServerCert Property (SNMPTCPAgent Component)

Instructs the component to unconditionally accept the server certificate that matches the supplied certificate.

Syntax

• C#
• VB.NET

public Certificate SSLAcceptServerCert { get; set; }

Public Property SSLAcceptServerCert As Certificate

Remarks

If it finds any issues with the certificate presented by the server, the component will normally terminate the connection with an error.

You may override this behavior by supplying a value for SSLAcceptServerCert. If the certificate supplied in SSLAcceptServerCert is the same as the certificate presented by the server, then the server certificate is accepted unconditionally, and the connection will continue normally.

Please note that this functionality is provided only for cases where you otherwise know that you are communicating with the right server. If used improperly, this property may create a security breach. Use it at your own risk.

SSLAuthenticateClients Property (SNMPTCPAgent Component)

If set to True, the server asks the client(s) for a certificate.

Syntax

• C#
• VB.NET

public bool SSLAuthenticateClients { get; set; }

Public Property SSLAuthenticateClients As Boolean

Default Value

False

Remarks

This property is used in conjunction with the SSLClientAuthentication event. Please refer to the documentation of the SSLClientAuthentication event for details.

SSLCert Property (SNMPTCPAgent Component)

The certificate to be used during SSL negotiation.

Syntax

• C#
• VB.NET

public Certificate SSLCert { get; set; }

Public Property SSLCert As Certificate

Remarks

The digital certificate that the component will use during SSL negotiation. Set this property to a valid certificate before starting SSL negotiation. To set a certificate, you may set the Encoded field to the encoded certificate. To select a certificate, use the store and subject fields.

SSLEnabled Property (SNMPTCPAgent Component)

Whether TLS/SSL is enabled.

Syntax

• C#
• VB.NET

public bool SSLEnabled { get; set; }

Public Property SSLEnabled As Boolean

Default Value

False

Remarks

This setting specifies whether TLS/SSL is enabled in the component. When False (default) the component operates in plaintext mode. When True TLS/SSL is enabled.

Note: SSL is not currently supported in this product. This setting is reserved for future user.

This property is not available at design time.

SSLServerCert Property (SNMPTCPAgent Component)

The server certificate for the last established connection.

Syntax

• C#
• VB.NET

public Certificate SSLServerCert { get; }

Public ReadOnly Property SSLServerCert As Certificate

Remarks

SSLServerCert contains the server certificate for the last established connection.

SSLServerCert is reset every time a new connection is attempted.

This property is read-only.

SysUpTime Property (SNMPTCPAgent Component)

Time passed since the agent was initialized (in hundredths of a second).

Syntax

• C#
• VB.NET

public long SysUpTime { get; set; }

Public Property SysUpTime As Long

Default Value

0

Remarks

This property is used when sending SNMP traps, and it normally provides the time since the system was restarted in 1/100s of a second.

If another value is desired, you may set this property to a custom value. From that point on, SysUpTime will return the value set plus time elapsed.

This property is not available at design time.

Activate Method (SNMPTCPAgent Component)

Activates the component.

Syntax

• C#
• VB.NET

public void Activate();

Async Version
public async Task Activate();
public async Task Activate(CancellationToken cancellationToken);

Public Sub Activate()

Async Version
Public Sub Activate() As Task
Public Sub Activate(cancellationToken As CancellationToken) As Task

Remarks

This method activates the component and will allow it to send or receive data.

The component will be automatically activated if it is not already and you attempt to perform an operation which requires the component to be active.

Note: Use the Active property to check whether the component is active.

AddUser Method (SNMPTCPAgent Component)

Adds a user to the internal authentication cache.

Syntax

• C#
• VB.NET

public void AddUser(string user, int authenticationProtocol, string authenticationPassword, int encryptionAlgorithm, string encryptionPassword);

Async Version
public async Task AddUser(string user, int authenticationProtocol, string authenticationPassword, int encryptionAlgorithm, string encryptionPassword);
public async Task AddUser(string user, int authenticationProtocol, string authenticationPassword, int encryptionAlgorithm, string encryptionPassword, CancellationToken cancellationToken);

Public Sub AddUser(ByVal User As String, ByVal AuthenticationProtocol As Integer, ByVal AuthenticationPassword As String, ByVal EncryptionAlgorithm As Integer, ByVal EncryptionPassword As String)

Async Version
Public Sub AddUser(ByVal User As String, ByVal AuthenticationProtocol As Integer, ByVal AuthenticationPassword As String, ByVal EncryptionAlgorithm As Integer, ByVal EncryptionPassword As String) As Task
Public Sub AddUser(ByVal User As String, ByVal AuthenticationProtocol As Integer, ByVal AuthenticationPassword As String, ByVal EncryptionAlgorithm As Integer, ByVal EncryptionPassword As String, cancellationToken As CancellationToken) As Task

Remarks

The internal authentication cache can be used as an alternative to the GetUserPassword event, automatically checking the cache against the security parameters provided in the request signature.

The ShowCache method is used to show the contents of the internal authentication cache.

The ClearCache method can be used to completely clear the cache.

Valid Authentication Protocols are:

Valid Encryption Algorithms are:

NOTE: Specifying an authentication protocol of 0 is a special case where the component will attempt to verify users with all valid authentication protocols.

ClearCache Method (SNMPTCPAgent Component)

Clears the internal authentication database.

Syntax

• C#
• VB.NET

public void ClearCache();

Async Version
public async Task ClearCache();
public async Task ClearCache(CancellationToken cancellationToken);

Public Sub ClearCache()

Async Version
Public Sub ClearCache() As Task
Public Sub ClearCache(cancellationToken As CancellationToken) As Task

Remarks

All user records are removed from the internal authentication cache as a result of this call.

Config Method (SNMPTCPAgent Component)

Sets or retrieves a configuration setting.

Syntax

• C#
• VB.NET

public string Config(string configurationString);

Async Version
public async Task<string> Config(string configurationString);
public async Task<string> Config(string configurationString, CancellationToken cancellationToken);

Public Function Config(ByVal ConfigurationString As String) As String

Async Version
Public Function Config(ByVal ConfigurationString As String) As Task(Of String)
Public Function Config(ByVal ConfigurationString As String, cancellationToken As CancellationToken) As Task(Of String)

Remarks

Config is a generic method available in every component. It is used to set and retrieve configuration settings for the component.

These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the component, access to these internal properties is provided through the Config method.

To set a configuration setting named PROPERTY, you must call Config("PROPERTY=VALUE"), where VALUE is the value of the setting expressed as a string. For boolean values, use the strings "True", "False", "0", "1", "Yes", or "No" (case does not matter).

To read (query) the value of a configuration setting, you must call Config("PROPERTY"). The value will be returned as a string.

Deactivate Method (SNMPTCPAgent Component)

Deactivates the component.

Syntax

• C#
• VB.NET

public void Deactivate();

Async Version
public async Task Deactivate();
public async Task Deactivate(CancellationToken cancellationToken);

Public Sub Deactivate()

Async Version
Public Sub Deactivate() As Task
Public Sub Deactivate(cancellationToken As CancellationToken) As Task

Remarks

This method deactivates the component and will prohibit it from sending and receiving data.

Note: Use the Active property to check whether the component is active.

DoEvents Method (SNMPTCPAgent Component)

Processes events from the internal message queue.

Syntax

• C#
• VB.NET

public void DoEvents();

Async Version
public async Task DoEvents();
public async Task DoEvents(CancellationToken cancellationToken);

Public Sub DoEvents()

Async Version
Public Sub DoEvents() As Task
Public Sub DoEvents(cancellationToken As CancellationToken) As Task

Remarks

When DoEvents is called, the component processes any available events. If no events are available, it waits for a preset period of time, and then returns.

HashPasswords Method (SNMPTCPAgent Component)

Hashes all passwords in the cache.

Syntax

• C#
• VB.NET

public void HashPasswords();

Async Version
public async Task HashPasswords();
public async Task HashPasswords(CancellationToken cancellationToken);

Public Sub HashPasswords()

Async Version
Public Sub HashPasswords() As Task
Public Sub HashPasswords(cancellationToken As CancellationToken) As Task

Remarks

Forces computation of all passwords hashes in the cache. Used together with the HashPassword event to enable implementations of external password hash storage.

RemoveUser Method (SNMPTCPAgent Component)

Removes the user specified by User from the internal authentication cache.

Syntax

• C#
• VB.NET

public void RemoveUser(string user);

Async Version
public async Task RemoveUser(string user);
public async Task RemoveUser(string user, CancellationToken cancellationToken);

Public Sub RemoveUser(ByVal User As String)

Async Version
Public Sub RemoveUser(ByVal User As String) As Task
Public Sub RemoveUser(ByVal User As String, cancellationToken As CancellationToken) As Task

Remarks

The internal authentication cache can be used as an alternative to the GetUserPassword event, automatically checking the cache against the security parameters provided in the request signature.

The ShowCache method is used to show the contents of the internal authentication cache.

The ClearCache method can be used to completely clear the cache.

Reset Method (SNMPTCPAgent Component)

Clears the object arrays.

Syntax

• C#
• VB.NET

public void Reset();

Async Version
public async Task Reset();
public async Task Reset(CancellationToken cancellationToken);

Public Sub Reset()

Async Version
Public Sub Reset() As Task
Public Sub Reset(cancellationToken As CancellationToken) As Task

Remarks

Clears the object arrays, and sets the trap and error properties to their default values. This is useful for reinitializing all the properties that are used to create outgoing packets before building a new packet.

Note: SNMPVersion will be reset to snmpverV2c (2).

SendResponse Method (SNMPTCPAgent Component)

Sends a response packet to a Get, Get-Next, Get-Bulk, or Set request.

Syntax

• C#
• VB.NET

public void SendResponse(string remoteHost, int remotePort, int requestId, string community, int errorStatus, int errorIndex);

Async Version
public async Task SendResponse(string remoteHost, int remotePort, int requestId, string community, int errorStatus, int errorIndex);
public async Task SendResponse(string remoteHost, int remotePort, int requestId, string community, int errorStatus, int errorIndex, CancellationToken cancellationToken);

Public Sub SendResponse(ByVal RemoteHost As String, ByVal RemotePort As Integer, ByVal RequestId As Integer, ByVal Community As String, ByVal ErrorStatus As Integer, ByVal ErrorIndex As Integer)

Async Version
Public Sub SendResponse(ByVal RemoteHost As String, ByVal RemotePort As Integer, ByVal RequestId As Integer, ByVal Community As String, ByVal ErrorStatus As Integer, ByVal ErrorIndex As Integer) As Task
Public Sub SendResponse(ByVal RemoteHost As String, ByVal RemotePort As Integer, ByVal RequestId As Integer, ByVal Community As String, ByVal ErrorStatus As Integer, ByVal ErrorIndex As Integer, cancellationToken As CancellationToken) As Task

Remarks

Use this method to send asynchronous response packets. A valid RequestId must be specified. SendResponse sends an unauthenticated response packet. Depending upon the value of the SNMPVersion property, the packet is constructed as an SNMPv1, SNMPv2c, or SNMPv3 (unauthenticated) response PDU. To send authenticated or encrypted SNMPv3 responses, use SendSecureResponse

The RemoteHost and RemotePort parameters are used to determine where the response is to be sent. The object identifiers, types, and values for the request are taken from the Objects collection. The RequestId, Community, ErrorStatus, and ErrorIndex parameters are used to specify other properties of the response.

SendSecureResponse Method (SNMPTCPAgent Component)

Sends an authenticated and/or encrypted SNMPv3 response.

Syntax

• C#
• VB.NET

public void SendSecureResponse(string remoteHost, int remotePort, int requestId, int messageId, int errorStatus, int errorIndex, string user, int authenticationProtocol, string authenticationPassword, int encryptionAlgorithm, string encryptionPassword);

Async Version
public async Task SendSecureResponse(string remoteHost, int remotePort, int requestId, int messageId, int errorStatus, int errorIndex, string user, int authenticationProtocol, string authenticationPassword, int encryptionAlgorithm, string encryptionPassword);
public async Task SendSecureResponse(string remoteHost, int remotePort, int requestId, int messageId, int errorStatus, int errorIndex, string user, int authenticationProtocol, string authenticationPassword, int encryptionAlgorithm, string encryptionPassword, CancellationToken cancellationToken);

Public Sub SendSecureResponse(ByVal RemoteHost As String, ByVal RemotePort As Integer, ByVal RequestId As Integer, ByVal MessageId As Integer, ByVal ErrorStatus As Integer, ByVal ErrorIndex As Integer, ByVal User As String, ByVal AuthenticationProtocol As Integer, ByVal AuthenticationPassword As String, ByVal EncryptionAlgorithm As Integer, ByVal EncryptionPassword As String)

Async Version
Public Sub SendSecureResponse(ByVal RemoteHost As String, ByVal RemotePort As Integer, ByVal RequestId As Integer, ByVal MessageId As Integer, ByVal ErrorStatus As Integer, ByVal ErrorIndex As Integer, ByVal User As String, ByVal AuthenticationProtocol As Integer, ByVal AuthenticationPassword As String, ByVal EncryptionAlgorithm As Integer, ByVal EncryptionPassword As String) As Task
Public Sub SendSecureResponse(ByVal RemoteHost As String, ByVal RemotePort As Integer, ByVal RequestId As Integer, ByVal MessageId As Integer, ByVal ErrorStatus As Integer, ByVal ErrorIndex As Integer, ByVal User As String, ByVal AuthenticationProtocol As Integer, ByVal AuthenticationPassword As String, ByVal EncryptionAlgorithm As Integer, ByVal EncryptionPassword As String, cancellationToken As CancellationToken) As Task

Remarks

Similar to the SendResponse method except that User, Authentication Protocol, and AuthenticationPassword are used to authenticate the response. EncryptionAlgorithm and EncryptionPassword (if not empty) are used to encrypt the response.

The MessageId argument must match the MessageId parameter obtained from the GetRequest, GetNextRequest, SetRequest, or GetBulkRequest event.

The user and password arguments used to send the response will be added to the internal user cache. If the user is already in the cache, its passwords will be updated with those supplied.

Valid Authentication Protocols are:

Valid Encryption Algorithms are:

SendSecureTrap Method (SNMPTCPAgent Component)

Sends an authenticated and/or encrypted SNMPv3 trap.

Syntax

• C#
• VB.NET

public void SendSecureTrap(string remoteHost, string trapOID, string user, int authenticationProtocol, string authenticationPassword, int encryptionAlgorithm, string encryptionPassword);

Async Version
public async Task SendSecureTrap(string remoteHost, string trapOID, string user, int authenticationProtocol, string authenticationPassword, int encryptionAlgorithm, string encryptionPassword);
public async Task SendSecureTrap(string remoteHost, string trapOID, string user, int authenticationProtocol, string authenticationPassword, int encryptionAlgorithm, string encryptionPassword, CancellationToken cancellationToken);

Public Sub SendSecureTrap(ByVal RemoteHost As String, ByVal TrapOID As String, ByVal User As String, ByVal AuthenticationProtocol As Integer, ByVal AuthenticationPassword As String, ByVal EncryptionAlgorithm As Integer, ByVal EncryptionPassword As String)

Async Version
Public Sub SendSecureTrap(ByVal RemoteHost As String, ByVal TrapOID As String, ByVal User As String, ByVal AuthenticationProtocol As Integer, ByVal AuthenticationPassword As String, ByVal EncryptionAlgorithm As Integer, ByVal EncryptionPassword As String) As Task
Public Sub SendSecureTrap(ByVal RemoteHost As String, ByVal TrapOID As String, ByVal User As String, ByVal AuthenticationProtocol As Integer, ByVal AuthenticationPassword As String, ByVal EncryptionAlgorithm As Integer, ByVal EncryptionPassword As String, cancellationToken As CancellationToken) As Task

Remarks

Similar to the SendTrap method except that User, AuthenticationPassword, and Authentication Protocol are used to authenticate the trap. EncryptionPassword (if not empty) and EncryptionAlgorithm are used to encrypt the message.

The user and password arguments used to send the trap will be added to the internal user cache. If the user is already in the cache, its passwords will be updated with those supplied.

Valid Authentication Protocols are:

Valid Encryption Algorithms are:

SendTrap Method (SNMPTCPAgent Component)

Sends an SNMP Trap.

Syntax

• C#
• VB.NET

public void SendTrap(string remoteHost, string trapOID);

Async Version
public async Task SendTrap(string remoteHost, string trapOID);
public async Task SendTrap(string remoteHost, string trapOID, CancellationToken cancellationToken);

Public Sub SendTrap(ByVal RemoteHost As String, ByVal TrapOID As String)

Async Version
Public Sub SendTrap(ByVal RemoteHost As String, ByVal TrapOID As String) As Task
Public Sub SendTrap(ByVal RemoteHost As String, ByVal TrapOID As String, cancellationToken As CancellationToken) As Task

Remarks

Depending upon the value of the SNMPVersion property, the packet is constructed as an SNMPv1 or SNMPv2 Trap PDU. The following configuration settings provide more control about how traps are generated: TrapPort, TrapAgentAddress, TrapCommunity, TrapEnterprise. The SysUpTime property provides the trap timestamp.

SendTrap sends an unauthenticated trap. The SendSecureTrap method is used to send authenticated SNMPv3 traps.

If any values are provided in the Objects collection, they are sent unchanged. In the case of an SNMPv2 or SNMPv3 Trap, if Objects has a count that is equal to 0, the following values are set: sysUpTime.0 equal to SysUpTime and snmpTrapOID.0 equal to TrapOID.

For SNMPv2 and SNMPv3 Traps, TrapOID must contain the full OID of the Trap. For SNMPv1, TrapOID must be a string of the form "generic.specific" where generic and specific are numeric values providing the Trap Generic Type and Specific Type.

For SNMPv1, TrapOID must be of the form "GenericTrap.SpecificTrap". These values are sent in the PDU header. TrapAgentAddress and TrapEnterprise are taken from the corresponding configuration settings.

Additionally, the following symbolic values are recognized and translated as follows:

ShowCache Method (SNMPTCPAgent Component)

Lists all entries in the internal user authentication cache.

Syntax

• C#
• VB.NET

public void ShowCache();

Async Version
public async Task ShowCache();
public async Task ShowCache(CancellationToken cancellationToken);

Public Sub ShowCache()

Async Version
Public Sub ShowCache() As Task
Public Sub ShowCache(cancellationToken As CancellationToken) As Task

Remarks

A CacheEntry event is fired for every record in the internal user authentication cache.

The internal authentication cache can be used as an alternative to the GetUserPassword event, automatically checking the cache against the security parameters provided in the request signature.

The ShowCache method is used to show the contents of the internal authentication cache.

The ClearCache method can be used to completely clear the cache.

Value Method (SNMPTCPAgent Component)

Returns the value corresponding to an OID.

Syntax

• C#
• VB.NET

public string Value(string OID);

Async Version
public async Task<string> Value(string OID);
public async Task<string> Value(string OID, CancellationToken cancellationToken);

Public Function Value(ByVal OID As String) As String

Async Version
Public Function Value(ByVal OID As String) As Task(Of String)
Public Function Value(ByVal OID As String, cancellationToken As CancellationToken) As Task(Of String)

Remarks

If the OID does not exist in the Objects collection, a trappable error is generated.

Please refer to the SNMPObject type for more information.

BadPacket Event (SNMPTCPAgent Component)

Fired for erroneous and/or malformed messages.

Syntax

• C#
• VB.NET

public event OnBadPacketHandler OnBadPacket;

public delegate void OnBadPacketHandler(object sender, SnmptcpagentBadPacketEventArgs e);

public class SnmptcpagentBadPacketEventArgs : EventArgs {
  public string Packet { get; }
  public byte[] PacketB { get; }
  public string SourceAddress { get; }
  public int SourcePort { get; }
  public int ErrorCode { get; }
  public string ErrorDescription { get; }
  public bool Report { get; set; }
}

Public Event OnBadPacket As OnBadPacketHandler

Public Delegate Sub OnBadPacketHandler(sender As Object, e As SnmptcpagentBadPacketEventArgs)

Public Class SnmptcpagentBadPacketEventArgs Inherits EventArgs
  Public ReadOnly Property Packet As String
  Public ReadOnly Property PacketB As Byte()
  Public ReadOnly Property SourceAddress As String
  Public ReadOnly Property SourcePort As Integer
  Public ReadOnly Property ErrorCode As Integer
  Public ReadOnly Property ErrorDescription As String
  Public Property Report As Boolean
End Class

Remarks

The full message is provided in the Packet parameter.

The BadPacket event is also fired when authentication fails for received packets due to a bad password or other reasons.

If the Report parameter is set to True, an unauthenticated error report will be sent to the client, otherwise the packet will be silently ignored.

Please refer to the GetUserPassword event for more information concerning SNMPv3 authentication.

CacheEntry Event (SNMPTCPAgent Component)

Shows in the internal cache.

Syntax

• C#
• VB.NET

public event OnCacheEntryHandler OnCacheEntry;

public delegate void OnCacheEntryHandler(object sender, SnmptcpagentCacheEntryEventArgs e);

public class SnmptcpagentCacheEntryEventArgs : EventArgs {
  public string User { get; }
  public string AuthenticationProtocol { get; }
  public string AuthenticationPassword { get; }
  public string EncryptionAlgorithm { get; }
  public string EncryptionPassword { get; }
}

Public Event OnCacheEntry As OnCacheEntryHandler

Public Delegate Sub OnCacheEntryHandler(sender As Object, e As SnmptcpagentCacheEntryEventArgs)

Public Class SnmptcpagentCacheEntryEventArgs Inherits EventArgs
  Public ReadOnly Property User As String
  Public ReadOnly Property AuthenticationProtocol As String
  Public ReadOnly Property AuthenticationPassword As String
  Public ReadOnly Property EncryptionAlgorithm As String
  Public ReadOnly Property EncryptionPassword As String
End Class

Remarks

CacheEntry events are triggered by a call to ShowCache. One event is fired for each user.

Connected Event (SNMPTCPAgent Component)

Fired immediately after a connection completes (or fails).

Syntax

• C#
• VB.NET

public event OnConnectedHandler OnConnected;

public delegate void OnConnectedHandler(object sender, SnmptcpagentConnectedEventArgs e);

public class SnmptcpagentConnectedEventArgs : EventArgs {
  public string RemoteAddress { get; }
  public int RemotePort { get; }
  public int StatusCode { get; }
  public string Description { get; }
}

Public Event OnConnected As OnConnectedHandler

Public Delegate Sub OnConnectedHandler(sender As Object, e As SnmptcpagentConnectedEventArgs)

Public Class SnmptcpagentConnectedEventArgs Inherits EventArgs
  Public ReadOnly Property RemoteAddress As String
  Public ReadOnly Property RemotePort As Integer
  Public ReadOnly Property StatusCode As Integer
  Public ReadOnly Property Description As String
End Class

Remarks

This event fires after a connection completes or fails.

StatusCode is the value returned by the system TCP/IP stack. This will be 0 if the connection was successful.

Description contains a human readable description of the status. This will be "OK" if the connection was successful.

RemoteAddress is the IP address of the remote host.

RemotePort is the port on the remote host.

ConnectionStatus Event (SNMPTCPAgent Component)

This event is fired to indicate changes in the connection state.

Syntax

• C#
• VB.NET

public event OnConnectionStatusHandler OnConnectionStatus;

public delegate void OnConnectionStatusHandler(object sender, SnmptcpagentConnectionStatusEventArgs e);

public class SnmptcpagentConnectionStatusEventArgs : EventArgs {
  public string ConnectionEvent { get; }
  public int StatusCode { get; }
  public string Description { get; }
}

Public Event OnConnectionStatus As OnConnectionStatusHandler

Public Delegate Sub OnConnectionStatusHandler(sender As Object, e As SnmptcpagentConnectionStatusEventArgs)

Public Class SnmptcpagentConnectionStatusEventArgs Inherits EventArgs
  Public ReadOnly Property ConnectionEvent As String
  Public ReadOnly Property StatusCode As Integer
  Public ReadOnly Property Description As String
End Class

Remarks

The ConnectionStatus event is fired when the connection state changes: for example, completion of a firewall or proxy connection or completion of a security handshake.

The ConnectionEvent parameter indicates the type of connection event. Values may include the following:

Description contains a description of this code. The value of StatusCode is equal to the value of the error.

Disconnected Event (SNMPTCPAgent Component)

Fired when a connection is closed.

Syntax

• C#
• VB.NET

public event OnDisconnectedHandler OnDisconnected;

public delegate void OnDisconnectedHandler(object sender, SnmptcpagentDisconnectedEventArgs e);

public class SnmptcpagentDisconnectedEventArgs : EventArgs {
  public string RemoteAddress { get; }
  public int RemotePort { get; }
  public int StatusCode { get; }
  public string Description { get; }
}

Public Event OnDisconnected As OnDisconnectedHandler

Public Delegate Sub OnDisconnectedHandler(sender As Object, e As SnmptcpagentDisconnectedEventArgs)

Public Class SnmptcpagentDisconnectedEventArgs Inherits EventArgs
  Public ReadOnly Property RemoteAddress As String
  Public ReadOnly Property RemotePort As Integer
  Public ReadOnly Property StatusCode As Integer
  Public ReadOnly Property Description As String
End Class

Remarks

This event fires after a connection is broken.

StatusCode is the value returned by the system TCP/IP stack. This will be 0 if the connection was broken normally.

Description contains a human readable description of the status. This will be "OK" if the connection was broken normally.

RemoteAddress is the IP address of the remote host.

RemotePort is the port on the remote host.

DiscoveryRequest Event (SNMPTCPAgent Component)

Fired when an SNMPv3 discovery packet is received.

Syntax

• C#
• VB.NET

public event OnDiscoveryRequestHandler OnDiscoveryRequest;

public delegate void OnDiscoveryRequestHandler(object sender, SnmptcpagentDiscoveryRequestEventArgs e);

public class SnmptcpagentDiscoveryRequestEventArgs : EventArgs {
  public string EngineId { get; }
  public byte[] EngineIdB { get; }
  public int EngineBoots { get; }
  public int EngineTime { get; }
  public string User { get; }
  public int SecurityLevel { get; }
  public string SourceAddress { get; }
  public int SourcePort { get; }
  public bool Respond { get; set; }
}

Public Event OnDiscoveryRequest As OnDiscoveryRequestHandler

Public Delegate Sub OnDiscoveryRequestHandler(sender As Object, e As SnmptcpagentDiscoveryRequestEventArgs)

Public Class SnmptcpagentDiscoveryRequestEventArgs Inherits EventArgs
  Public ReadOnly Property EngineId As String
  Public ReadOnly Property EngineIdB As Byte()
  Public ReadOnly Property EngineBoots As Integer
  Public ReadOnly Property EngineTime As Integer
  Public ReadOnly Property User As String
  Public ReadOnly Property SecurityLevel As Integer
  Public ReadOnly Property SourceAddress As String
  Public ReadOnly Property SourcePort As Integer
  Public Property Respond As Boolean
End Class

Remarks

EngineId, EngineBoots, EngineTime, and User are the values received from SourceAddress.

For SNMPv3, the User parameter shows the user that was supplied with the packet. This parameter MUST be used together with the SecurityLevel parameter which shows the level of security in the message.

The SecurityLevel parameter shows whether the request has been authenticated. If SecurityLevel is 0, the request has NOT been authenticated (i.e. the packet signature has not been verified). For an authenticated, non encrypted request, SecurityLevel is 1. For an authenticated and encrypted request, SecurityLevel is 2.

Respond is True by default, and will automatically send a response using the value in LocalEngineId. To suppress the response, set Respond to False.

The value returned to SourceAddress for EngineBoots is always 0, and EngineTime is the number of seconds since January 1st, 1970 (GMT).

Error Event (SNMPTCPAgent Component)

Fired when information is available about errors during data delivery.

Syntax

• C#
• VB.NET

public event OnErrorHandler OnError;

public delegate void OnErrorHandler(object sender, SnmptcpagentErrorEventArgs e);

public class SnmptcpagentErrorEventArgs : EventArgs {
  public int ErrorCode { get; }
  public string Description { get; }
}

Public Event OnError As OnErrorHandler

Public Delegate Sub OnErrorHandler(sender As Object, e As SnmptcpagentErrorEventArgs)

Public Class SnmptcpagentErrorEventArgs Inherits EventArgs
  Public ReadOnly Property ErrorCode As Integer
  Public ReadOnly Property Description As String
End Class

Remarks

The Error event is fired in case of exceptional conditions during message processing. Normally the component throws an exception.

The ErrorCode parameter contains an error code, and the Description parameter contains a textual description of the error. For a list of valid error codes and their descriptions, please refer to the Error Codes section.

GetBulkRequest Event (SNMPTCPAgent Component)

Fired when a GetBulkRequest packet is received.

Syntax

• C#
• VB.NET

public event OnGetBulkRequestHandler OnGetBulkRequest;

public delegate void OnGetBulkRequestHandler(object sender, SnmptcpagentGetBulkRequestEventArgs e);

public class SnmptcpagentGetBulkRequestEventArgs : EventArgs {
  public int RequestId { get; }
  public int MessageId { get; }
  public int SNMPVersion { get; }
  public string Community { get; }
  public string User { get; }
  public int SecurityLevel { get; }
  public string SourceAddress { get; }
  public int SourcePort { get; }
  public int NonRepeaters { get; }
  public int MaxRepetitions { get; }
  public int ErrorIndex { get; set; }
  public int ErrorStatus { get; set; }
  public string ErrorDescription { get; }
  public bool Respond { get; set; }
}

Public Event OnGetBulkRequest As OnGetBulkRequestHandler

Public Delegate Sub OnGetBulkRequestHandler(sender As Object, e As SnmptcpagentGetBulkRequestEventArgs)

Public Class SnmptcpagentGetBulkRequestEventArgs Inherits EventArgs
  Public ReadOnly Property RequestId As Integer
  Public ReadOnly Property MessageId As Integer
  Public ReadOnly Property SNMPVersion As Integer
  Public ReadOnly Property Community As String
  Public ReadOnly Property User As String
  Public ReadOnly Property SecurityLevel As Integer
  Public ReadOnly Property SourceAddress As String
  Public ReadOnly Property SourcePort As Integer
  Public ReadOnly Property NonRepeaters As Integer
  Public ReadOnly Property MaxRepetitions As Integer
  Public Property ErrorIndex As Integer
  Public Property ErrorStatus As Integer
  Public ReadOnly Property ErrorDescription As String
  Public Property Respond As Boolean
End Class

Remarks

This is only available for SNMP versions 2 and 3.

The list of variables in the SNMP packet, including optional values and types, is provided through the Objects collection. Each object is of type SNMPObject. This type describes the Oid, ObjectType, and Value of each SNMP object. These variables must be copied to another location before the event has completed executing, or they may be overridden by other events.

The SourceAddress and SourcePort parameters show the address and port of the sender as reported by the TCP/IP stack.

The MessageId parameter identifies the received request.

For SNMPv3, the User parameter shows the user that was supplied with the packet. This parameter MUST be used together with the SecurityLevel parameter which shows the level of security in the message.

The SecurityLevel parameter shows whether the request has been authenticated. If SecurityLevel is 0, the request has NOT been authenticated (i.e. the packet signature has not been verified). For an authenticated, non encrypted request, SecurityLevel is 1. For an authenticated and encrypted request, SecurityLevel is 2.

To send a response, the Respond parameter must be set to true. By default, this value is false, which means no response will be sent. The ErrorStatus parameter may also be set to a valid SNMP status code (the default value is 0, which represents no error).

The following is a list of valid SNMP status code values:

Variable indexes start with 0. ErrorIndex has no meaning when ErrorStatus is 0 (no error).

A GetBulkRequest is very similar to a GetNextRequest, the difference is that Getbulk performs a continuous GetNext operation based on the MaxRepitions value. The NonRepeaters value will determine the number of Objects for which a simple GetNext operation should be performed. For the remaining variables, a continuous GetNext operation is performed based on the MaxRepitions value.

So if you send a request containing X objects, the agent will perform N simple GetNext operations and M continuous GetNext operations X - N times. With X being the number of objects received, N being the number of NonRepeaters, and M being the number of MaxRepitions. Thus the SNMPMgr is expecting to receive N + M x (X - N) objects, assuming that each object has M successors.

GetNextRequest Event (SNMPTCPAgent Component)

Fired when a GetNextRequest packet is received.

Syntax

• C#
• VB.NET

public event OnGetNextRequestHandler OnGetNextRequest;

public delegate void OnGetNextRequestHandler(object sender, SnmptcpagentGetNextRequestEventArgs e);

public class SnmptcpagentGetNextRequestEventArgs : EventArgs {
  public int RequestId { get; }
  public int MessageId { get; }
  public int SNMPVersion { get; }
  public string Community { get; }
  public string User { get; }
  public int SecurityLevel { get; }
  public string SourceAddress { get; }
  public int SourcePort { get; }
  public int ErrorIndex { get; set; }
  public int ErrorStatus { get; set; }
  public string ErrorDescription { get; }
  public bool Respond { get; set; }
}

Public Event OnGetNextRequest As OnGetNextRequestHandler

Public Delegate Sub OnGetNextRequestHandler(sender As Object, e As SnmptcpagentGetNextRequestEventArgs)

Public Class SnmptcpagentGetNextRequestEventArgs Inherits EventArgs
  Public ReadOnly Property RequestId As Integer
  Public ReadOnly Property MessageId As Integer
  Public ReadOnly Property SNMPVersion As Integer
  Public ReadOnly Property Community As String
  Public ReadOnly Property User As String
  Public ReadOnly Property SecurityLevel As Integer
  Public ReadOnly Property SourceAddress As String
  Public ReadOnly Property SourcePort As Integer
  Public Property ErrorIndex As Integer
  Public Property ErrorStatus As Integer
  Public ReadOnly Property ErrorDescription As String
  Public Property Respond As Boolean
End Class

Remarks

The list of variables in the SNMP packet, including optional values and types, is provided through the Objects collection. Each object is of type SNMPObject. This type describes the Oid, ObjectType, and Value of each SNMP object. These variables must be copied to another location before the event has completed executing, or they may be overridden by other events.

The SourceAddress and SourcePort parameters show the address and port of the sender as reported by the TCP/IP stack.

The MessageId parameter identifies the received request.

For SNMPv3, the User parameter shows the user that was supplied with the packet. This parameter MUST be used together with the SecurityLevel parameter which shows the level of security in the message.

The SecurityLevel parameter shows whether the request has been authenticated. If SecurityLevel is 0, the request has NOT been authenticated (i.e. the packet signature has not been verified). For an authenticated, non encrypted request, SecurityLevel is 1. For an authenticated and encrypted request, SecurityLevel is 2.

To send a response, the Respond parameter must be set to true. By default, this value is false, which means no response will be sent. The ErrorStatus parameter may also be set to a valid SNMP status code (the default value is 0, which represents no error).

The following is a list of valid SNMP status code values:

Variable indexes start with 0. ErrorIndex has no meaning when ErrorStatus is 0 (no error).

GetRequest Event (SNMPTCPAgent Component)

Fired when a GetRequest packet is received.

Syntax

• C#
• VB.NET

public event OnGetRequestHandler OnGetRequest;

public delegate void OnGetRequestHandler(object sender, SnmptcpagentGetRequestEventArgs e);

public class SnmptcpagentGetRequestEventArgs : EventArgs {
  public int RequestId { get; }
  public int MessageId { get; }
  public int SNMPVersion { get; }
  public string Community { get; }
  public string User { get; }
  public int SecurityLevel { get; }
  public string SourceAddress { get; }
  public int SourcePort { get; }
  public int ErrorIndex { get; set; }
  public int ErrorStatus { get; set; }
  public string ErrorDescription { get; }
  public bool Respond { get; set; }
}

Public Event OnGetRequest As OnGetRequestHandler

Public Delegate Sub OnGetRequestHandler(sender As Object, e As SnmptcpagentGetRequestEventArgs)

Public Class SnmptcpagentGetRequestEventArgs Inherits EventArgs
  Public ReadOnly Property RequestId As Integer
  Public ReadOnly Property MessageId As Integer
  Public ReadOnly Property SNMPVersion As Integer
  Public ReadOnly Property Community As String
  Public ReadOnly Property User As String
  Public ReadOnly Property SecurityLevel As Integer
  Public ReadOnly Property SourceAddress As String
  Public ReadOnly Property SourcePort As Integer
  Public Property ErrorIndex As Integer
  Public Property ErrorStatus As Integer
  Public ReadOnly Property ErrorDescription As String
  Public Property Respond As Boolean
End Class

Remarks

The list of variables in the SNMP packet, including optional values and types, is provided through the Objects collection. Each object is of type SNMPObject. This type describes the Oid, ObjectType, and Value of each SNMP object. These variables must be copied to another location before the event has completed executing, or they may be overridden by other events.

The SourceAddress and SourcePort parameters show the address and port of the sender as reported by the TCP/IP stack.

The MessageId parameter identifies the received request.

For SNMPv3, the User parameter shows the user that was supplied with the packet. This parameter MUST be used together with the SecurityLevel parameter which shows the level of security in the message.

The SecurityLevel parameter shows whether the request has been authenticated. If SecurityLevel is 0, the request has NOT been authenticated (i.e. the packet signature has not been verified). For an authenticated, non encrypted request, SecurityLevel is 1. For an authenticated and encrypted request, SecurityLevel is 2.

To send a response, the Respond parameter must be set to true. By default, this value is false, which means no response will be sent. The ErrorStatus parameter may also be set to a valid SNMP status code (the default value is 0, which represents no error).

The following is a list of valid SNMP status code values:

Variable indexes start with 0. ErrorIndex has no meaning when ErrorStatus is 0 (no error).

GetUserPassword Event (SNMPTCPAgent Component)

Retrieves a password associated with a user.

Syntax

• C#
• VB.NET

public event OnGetUserPasswordHandler OnGetUserPassword;

public delegate void OnGetUserPasswordHandler(object sender, SnmptcpagentGetUserPasswordEventArgs e);

public class SnmptcpagentGetUserPasswordEventArgs : EventArgs {
  public int PasswordType { get; }
  public string User { get; }
  public string Password { get; set; }
  public int Algorithm { get; set; }
}

Public Event OnGetUserPassword As OnGetUserPasswordHandler

Public Delegate Sub OnGetUserPasswordHandler(sender As Object, e As SnmptcpagentGetUserPasswordEventArgs)

Public Class SnmptcpagentGetUserPasswordEventArgs Inherits EventArgs
  Public ReadOnly Property PasswordType As Integer
  Public ReadOnly Property User As String
  Public Property Password As String
  Public Property Algorithm As Integer
End Class

Remarks

The GetUserPassword event is fired after initial inspection of SNMPv3 requests.

The type of password required is provided in the PasswordType parameter: 1 for authentication, and 2 for encryption (privacy).

The password corresponding to User (if any) must be provided in the Password parameter. If the password is valid, processing will continue to other events such as GetRequest, SetRequest, etc.

If the PasswordType parameter is 1 (authentication is used), the Algorithm parameter can be set. Possible values are:

If the password does not match the signature in the request, a BadPacket event will be fired, at which point you can decide whether to report the error to the client (see the description of the BadPacket event for more information).

If the User is invalid or unknown, set the password to empty string (default) to ignore the request. This will result in a BadPacket event being fired, at which point you can decide whether to report the error to the client or not.

GetUserSecurityLevel Event (SNMPTCPAgent Component)

Sets the security level for an incoming packet.

Syntax

• C#
• VB.NET

public event OnGetUserSecurityLevelHandler OnGetUserSecurityLevel;

public delegate void OnGetUserSecurityLevelHandler(object sender, SnmptcpagentGetUserSecurityLevelEventArgs e);

public class SnmptcpagentGetUserSecurityLevelEventArgs : EventArgs {
  public string User { get; }
  public string EngineId { get; }
  public byte[] EngineIdB { get; }
  public int SecurityLevel { get; set; }
}

Public Event OnGetUserSecurityLevel As OnGetUserSecurityLevelHandler

Public Delegate Sub OnGetUserSecurityLevelHandler(sender As Object, e As SnmptcpagentGetUserSecurityLevelEventArgs)

Public Class SnmptcpagentGetUserSecurityLevelEventArgs Inherits EventArgs
  Public ReadOnly Property User As String
  Public ReadOnly Property EngineId As String
  Public ReadOnly Property EngineIdB As Byte()
  Public Property SecurityLevel As Integer
End Class

Remarks

The GetUserSecurityLevel event is fired after the first inspection of each SNMPv3 request. The SecurityLevel parameter determines the level of security for the message.

On entry, the SecurityLevel parameter contains the default security level for User if the user is located in the internal cache, or if the User is not found in the cache, the SecurityLevel will be -1.

The value of SecurityLevel upon exiting the event, determines how the message will be processed:

HashPassword Event (SNMPTCPAgent Component)

Fired before and after a password is hashed.

Syntax

• C#
• VB.NET

public event OnHashPasswordHandler OnHashPassword;

public delegate void OnHashPasswordHandler(object sender, SnmptcpagentHashPasswordEventArgs e);

public class SnmptcpagentHashPasswordEventArgs : EventArgs {
  public string Password { get; }
  public int AuthAlgorithm { get; }
  public string Hash { get; set; }
}

Public Event OnHashPassword As OnHashPasswordHandler

Public Delegate Sub OnHashPasswordHandler(sender As Object, e As SnmptcpagentHashPasswordEventArgs)

Public Class SnmptcpagentHashPasswordEventArgs Inherits EventArgs
  Public ReadOnly Property Password As String
  Public ReadOnly Property AuthAlgorithm As Integer
  Public Property Hash As String
End Class

Remarks

SNMPv3 passwords are hashed in order to obtain authentication and encryption keys. This is an expensive operation, and in certain situations it may be preferable to store the hashed passwords externally and supply them on demand.

If a hash is required, the event fires with an empty string in the Hash parameter. In this case, you can choose to supply a value for the hash and stop the component from computing the hash.

The event also fires every time a hash is computed. In this case, the Hash parameter contains the value of the computed hash.

AuthAlgorithm contains either 1 for HMAC-MD5-96, 2 for HMAC-SHA-96 or 3 for HMAC-192-SHA-256

PacketTrace Event (SNMPTCPAgent Component)

Fired for every packet sent or received.

Syntax

• C#
• VB.NET

public event OnPacketTraceHandler OnPacketTrace;

public delegate void OnPacketTraceHandler(object sender, SnmptcpagentPacketTraceEventArgs e);

public class SnmptcpagentPacketTraceEventArgs : EventArgs {
  public string Packet { get; }
  public byte[] PacketB { get; }
  public int Direction { get; }
  public string PacketAddress { get; }
  public int PacketPort { get; }
}

Public Event OnPacketTrace As OnPacketTraceHandler

Public Delegate Sub OnPacketTraceHandler(sender As Object, e As SnmptcpagentPacketTraceEventArgs)

Public Class SnmptcpagentPacketTraceEventArgs Inherits EventArgs
  Public ReadOnly Property Packet As String
  Public ReadOnly Property PacketB As Byte()
  Public ReadOnly Property Direction As Integer
  Public ReadOnly Property PacketAddress As String
  Public ReadOnly Property PacketPort As Integer
End Class

Remarks

The PacketTrace event shows all the packets sent or received by the component.

Packet contains the full contents of the datagram.

Direction shows the direction of the packet: 1 for incoming packets, and 2 for outgoing packets.

In the case of an incoming packet, PacketAddress and PacketPort identify the source of the packet.

In the case of an outgoing packet, PacketAddress and PacketPort identify the destination of the packet.

ReadyToSend Event (SNMPTCPAgent Component)

Fired when the component is ready to send data.

Syntax

• C#
• VB.NET

public event OnReadyToSendHandler OnReadyToSend;

public delegate void OnReadyToSendHandler(object sender, SnmptcpagentReadyToSendEventArgs e);

public class SnmptcpagentReadyToSendEventArgs : EventArgs {
}

Public Event OnReadyToSend As OnReadyToSendHandler

Public Delegate Sub OnReadyToSendHandler(sender As Object, e As SnmptcpagentReadyToSendEventArgs)

Public Class SnmptcpagentReadyToSendEventArgs Inherits EventArgs
End Class

Remarks

The ReadyToSend event indicates that the underlying TCP/IP subsystem is ready to accept data after a failed DataToSend.

Report Event (SNMPTCPAgent Component)

Fired when a Report packet is received.

Syntax

• C#
• VB.NET

public event OnReportHandler OnReport;

public delegate void OnReportHandler(object sender, SnmptcpagentReportEventArgs e);

public class SnmptcpagentReportEventArgs : EventArgs {
  public int RequestId { get; }
  public int SNMPVersion { get; }
  public string Community { get; }
  public string User { get; }
  public int SecurityLevel { get; }
  public string SourceAddress { get; }
  public int SourcePort { get; }
  public int ErrorIndex { get; }
  public int ErrorStatus { get; }
  public string ErrorDescription { get; }
}

Public Event OnReport As OnReportHandler

Public Delegate Sub OnReportHandler(sender As Object, e As SnmptcpagentReportEventArgs)

Public Class SnmptcpagentReportEventArgs Inherits EventArgs
  Public ReadOnly Property RequestId As Integer
  Public ReadOnly Property SNMPVersion As Integer
  Public ReadOnly Property Community As String
  Public ReadOnly Property User As String
  Public ReadOnly Property SecurityLevel As Integer
  Public ReadOnly Property SourceAddress As String
  Public ReadOnly Property SourcePort As Integer
  Public ReadOnly Property ErrorIndex As Integer
  Public ReadOnly Property ErrorStatus As Integer
  Public ReadOnly Property ErrorDescription As String
End Class

Remarks

For SNMPv3, the User parameter shows the user that was supplied with the packet. This parameter MUST be used together with the SecurityLevel parameter which shows the level of security in the message.

The SecurityLevel parameter shows whether the request has been authenticated. If SecurityLevel is 0, the request has NOT been authenticated (i.e. the packet signature has not been verified). For an authenticated, non encrypted request, SecurityLevel is 1. For an authenticated and encrypted request, SecurityLevel is 2.

The list of variables in the SNMP packet, including optional values and types, is provided through the Objects collection. Each object is of type SNMPObject. This type describes the Oid, ObjectType, and Value of each SNMP object. These variables must be copied to another location before the event has completed executing, or they may be overridden by other events.

The SourceAddress and SourcePort parameters show the address and port of the sender as reported by the TCP/IP stack.

SetRequest Event (SNMPTCPAgent Component)

Fired when a SetRequest packet is received.

Syntax

• C#
• VB.NET

public event OnSetRequestHandler OnSetRequest;

public delegate void OnSetRequestHandler(object sender, SnmptcpagentSetRequestEventArgs e);

public class SnmptcpagentSetRequestEventArgs : EventArgs {
  public int RequestId { get; }
  public int MessageId { get; }
  public int SNMPVersion { get; }
  public string Community { get; }
  public string User { get; }
  public int SecurityLevel { get; }
  public string SourceAddress { get; }
  public int SourcePort { get; }
  public int ErrorIndex { get; set; }
  public int ErrorStatus { get; set; }
  public string ErrorDescription { get; }
  public bool Respond { get; set; }
}

Public Event OnSetRequest As OnSetRequestHandler

Public Delegate Sub OnSetRequestHandler(sender As Object, e As SnmptcpagentSetRequestEventArgs)

Public Class SnmptcpagentSetRequestEventArgs Inherits EventArgs
  Public ReadOnly Property RequestId As Integer
  Public ReadOnly Property MessageId As Integer
  Public ReadOnly Property SNMPVersion As Integer
  Public ReadOnly Property Community As String
  Public ReadOnly Property User As String
  Public ReadOnly Property SecurityLevel As Integer
  Public ReadOnly Property SourceAddress As String
  Public ReadOnly Property SourcePort As Integer
  Public Property ErrorIndex As Integer
  Public Property ErrorStatus As Integer
  Public ReadOnly Property ErrorDescription As String
  Public Property Respond As Boolean
End Class

Remarks

The list of variables in the SNMP packet, including optional values and types, is provided through the Objects collection. Each object is of type SNMPObject. This type describes the Oid, ObjectType, and Value of each SNMP object. These variables must be copied to another location before the event has completed executing, or they may be overridden by other events.

The SourceAddress and SourcePort parameters show the address and port of the sender as reported by the TCP/IP stack.

The MessageId parameter identifies the received request.

For SNMPv3, the User parameter shows the user that was supplied with the packet. This parameter MUST be used together with the SecurityLevel parameter which shows the level of security in the message.

The SecurityLevel parameter shows whether the request has been authenticated. If SecurityLevel is 0, the request has NOT been authenticated (i.e. the packet signature has not been verified). For an authenticated, non encrypted request, SecurityLevel is 1. For an authenticated and encrypted request, SecurityLevel is 2.

To send a response, the Respond parameter must be set to true. By default, this value is false, which means no response will be sent. The ErrorStatus parameter may also be set to a valid SNMP status code (the default value is 0, which represents no error).

The following is a list of valid SNMP status code values:

Variable indexes start with 0. ErrorIndex has no meaning when ErrorStatus is 0 (no error).

SSLClientAuthentication Event (SNMPTCPAgent Component)

Fired when the client presents its credentials to the server.

Syntax

• C#
• VB.NET

public event OnSSLClientAuthenticationHandler OnSSLClientAuthentication;

public delegate void OnSSLClientAuthenticationHandler(object sender, SnmptcpagentSSLClientAuthenticationEventArgs e);

public class SnmptcpagentSSLClientAuthenticationEventArgs : EventArgs {
  public string RemoteAddress { get; }
  public int RemotePort { get; }
  public string CertEncoded { get; }
  public byte[] CertEncodedB { get; }
  public string CertSubject { get; }
  public string CertIssuer { get; }
  public string Status { get; }
  public bool Accept { get; set; }
}

Public Event OnSSLClientAuthentication As OnSSLClientAuthenticationHandler

Public Delegate Sub OnSSLClientAuthenticationHandler(sender As Object, e As SnmptcpagentSSLClientAuthenticationEventArgs)

Public Class SnmptcpagentSSLClientAuthenticationEventArgs Inherits EventArgs
  Public ReadOnly Property RemoteAddress As String
  Public ReadOnly Property RemotePort As Integer
  Public ReadOnly Property CertEncoded As String
  Public ReadOnly Property CertEncodedB As Byte()
  Public ReadOnly Property CertSubject As String
  Public ReadOnly Property CertIssuer As String
  Public ReadOnly Property Status As String
  Public Property Accept As Boolean
End Class

Remarks

This event fires when a client connects to the component and presents a certificate for authentication. The Accept parameter is a recommendation on whether to continue or close the connection. This is just a suggestion: application software must use its own logic to determine whether to continue or not.

When Accept is False, Status shows why the verification failed (otherwise, Status contains the string "OK").

RemoteAddress is the IP address of the connecting client.

RemotePort is the source port of the connecting client.

CertEncoded is the base64 encoded certificate presented by the client.

CertSubject is the subject of the certificate presented by the client.

CertIssuer is the subject of the issuer of the certificate presented by the client.

Status is the stauts of the certificate.

Accept defines whether the certificate is accepted.

SSLServerAuthentication Event (SNMPTCPAgent Component)

Fires when connecting to the server.

Syntax

• C#
• VB.NET

public event OnSSLServerAuthenticationHandler OnSSLServerAuthentication;

public delegate void OnSSLServerAuthenticationHandler(object sender, SnmptcpagentSSLServerAuthenticationEventArgs e);

public class SnmptcpagentSSLServerAuthenticationEventArgs : EventArgs {
  public string RemoteAddress { get; }
  public int RemotePort { get; }
  public string CertEncoded { get; }
  public byte[] CertEncodedB { get; }
  public string CertSubject { get; }
  public string CertIssuer { get; }
  public string Status { get; }
  public bool Accept { get; set; }
}

Public Event OnSSLServerAuthentication As OnSSLServerAuthenticationHandler

Public Delegate Sub OnSSLServerAuthenticationHandler(sender As Object, e As SnmptcpagentSSLServerAuthenticationEventArgs)

Public Class SnmptcpagentSSLServerAuthenticationEventArgs Inherits EventArgs
  Public ReadOnly Property RemoteAddress As String
  Public ReadOnly Property RemotePort As Integer
  Public ReadOnly Property CertEncoded As String
  Public ReadOnly Property CertEncodedB As Byte()
  Public ReadOnly Property CertSubject As String
  Public ReadOnly Property CertIssuer As String
  Public ReadOnly Property Status As String
  Public Property Accept As Boolean
End Class

Remarks

This event is where the client can decide whether to continue with the connection process or not. The Accept parameter is a recommendation on whether to continue or close the connection. This is just a suggestion: application software must use its own logic to determine whether to continue or not.

When Accept is False, Status shows why the verification failed (otherwise, Status contains the string "OK"). If it is decided to continue, you can override and accept the certificate by setting the Accept parameter to True.

RemoteAddress is the IP address of the server.

RemotePort is the source port of the server.

CertEncoded is the base64 encoded certificate presented by the server.

CertSubject is the subject of the certificate presented by the server.

CertIssuer is the subject of the issuer of the certificate presented by the server.

Status is the stauts of the certificate.

Accept defines whether the certificate is accepted.

SSLStatus Event (SNMPTCPAgent Component)

Shows the progress of the secure connection.

Syntax

• C#
• VB.NET

public event OnSSLStatusHandler OnSSLStatus;

public delegate void OnSSLStatusHandler(object sender, SnmptcpagentSSLStatusEventArgs e);

public class SnmptcpagentSSLStatusEventArgs : EventArgs {
  public string RemoteAddress { get; }
  public int RemotePort { get; }
  public string Message { get; }
}

Public Event OnSSLStatus As OnSSLStatusHandler

Public Delegate Sub OnSSLStatusHandler(sender As Object, e As SnmptcpagentSSLStatusEventArgs)

Public Class SnmptcpagentSSLStatusEventArgs Inherits EventArgs
  Public ReadOnly Property RemoteAddress As String
  Public ReadOnly Property RemotePort As Integer
  Public ReadOnly Property Message As String
End Class

Remarks

The event is fired for informational and logging purposes only. It is used to track the progress of the connection.

RemoteAddress is the IP address of the remote machine.

RemotePort is the port of the remote machine.

Message is the log message.

Certificate Type

This is the digital certificate being used.

Remarks

This type describes the current digital certificate. The certificate may be a public or private key. The fields are used to identify or select certificates.

Fields

Constructors

• C#
• VB.NET

public Certificate();

Public Certificate()

Creates a Certificate instance whose properties can be set. This is useful for use with CERTMGR when generating new certificates.

• C#
• VB.NET

public Certificate(string certificateFile);

Public Certificate(ByVal CertificateFile As String)

Opens CertificateFile and reads out the contents as an X.509 public key.

• C#
• VB.NET

public Certificate(byte[] certificateData);

Public Certificate(ByVal CertificateData As Byte())

Parses CertificateData as an X.509 public key.

• C#
• VB.NET

public Certificate(CertStoreTypes certStoreType, string store, string storePassword, string subject);

Public Certificate(ByVal CertStoreType As CertStoreTypes, ByVal Store As String, ByVal StorePassword As String, ByVal Subject As String)

CertStoreType identifies the type of certificate store to use. See StoreType for descriptions of the different certificate stores. Store is a file containing the certificate store. StorePassword is the password used to protect the store. After the store has been successfully opened, the component will attempt to find the certificate identified by Subject . This can be either a complete or a substring match of the X.509 certificate's subject Distinguished Name (DN).

• C#
• VB.NET

public Certificate(CertStoreTypes certStoreType, string store, string storePassword, string subject, string configurationString);

Public Certificate(ByVal CertStoreType As CertStoreTypes, ByVal Store As String, ByVal StorePassword As String, ByVal Subject As String, ByVal ConfigurationString As String)

CertStoreType identifies the type of certificate store to use. See StoreType for descriptions of the different certificate stores. Store is a file containing the certificate store. StorePassword is the password used to protect the store. ConfigurationString is a newline separated list of name-value pairs that may be used to modify the default behavior. Possible values include "PersistPFXKey", which shows whether or not the PFX key is persisted after performing operations with the private key. This correlates to the PKCS12_NO_PERSIST_KEY CryptoAPI option. The default value is True (the key is persisted). "Thumbprint" - an MD5, SHA-1, or SHA-256 thumbprint of the certificate to load. When specified, this value is used to select the certificate in the store. This is applicable to cstUser, cstMachine, cstPublicKeyFile, and cstPFXFile store types. "UseInternalSecurityAPI" shows whether the platform (default) or the internal security API is used when performing certificate-related operations. After the store has been successfully opened, the component will attempt to find the certificate identified by Subject . This can be either a complete or a substring match of the X.509 certificate's subject Distinguished Name (DN).

• C#
• VB.NET

public Certificate(CertStoreTypes certStoreType, string store, string storePassword, byte[] encoded);

Public Certificate(ByVal CertStoreType As CertStoreTypes, ByVal Store As String, ByVal StorePassword As String, ByVal Encoded As Byte())

CertStoreType identifies the type of certificate store to use. See StoreType for descriptions of the different certificate stores. Store is a file containing the certificate store. StorePassword is the password used to protect the store. After the store has been successfully opened, the component will load Encoded as an X.509 certificate and search the opened store for a corresponding private key.

• C#
• VB.NET

public Certificate(CertStoreTypes certStoreType, byte[] storeBlob, string storePassword, string subject);

Public Certificate(ByVal CertStoreType As CertStoreTypes, ByVal StoreBlob As Byte(), ByVal StorePassword As String, ByVal Subject As String)

CertStoreType identifies the type of certificate store to use. See StoreType for descriptions of the different certificate stores. StoreBlob is a string (binary- or Base64-encoded) containing the certificate data. StorePassword is the password used to protect the store. After the store has been successfully opened, the component will attempt to find the certificate identified by Subject . This can be either a complete or a substring match of the X.509 certificate's subject Distinguished Name (DN).

• C#
• VB.NET

public Certificate(CertStoreTypes certStoreType, byte[] storeBlob, string storePassword, string subject, string configurationString);

Public Certificate(ByVal CertStoreType As CertStoreTypes, ByVal StoreBlob As Byte(), ByVal StorePassword As String, ByVal Subject As String, ByVal ConfigurationString As String)

CertStoreType identifies the type of certificate store to use. See StoreType for descriptions of the different certificate stores. StoreBlob is a string (binary- or Base64-encoded) containing the certificate data. StorePassword is the password used to protect the store. After the store has been successfully opened, the component will attempt to find the certificate identified by Subject . This can be either a complete or a substring match of the X.509 certificate's subject Distinguished Name (DN).

• C#
• VB.NET

public Certificate(CertStoreTypes certStoreType, byte[] storeBlob, string storePassword, byte[] encoded);

Public Certificate(ByVal CertStoreType As CertStoreTypes, ByVal StoreBlob As Byte(), ByVal StorePassword As String, ByVal Encoded As Byte())

CertStoreType identifies the type of certificate store to use. See StoreType for descriptions of the different certificate stores. Store is a string (binary- or Base64-encoded) containing the certificate store. StorePassword is the password used to protect the store. After the store has been successfully opened, the component will load Encoded as an X.509 certificate and search the opened store for a corresponding private key.

SNMPObject Type

The current SNMP object.

Remarks

This type defines an SNMP object. Each object has an Oid, ObjectType, and Value. These values are populated by the component when incoming packets are received. You may use these fields to define objects to be used in outgoing packets.

Fields

Constructors

• C#
• VB.NET

public SNMPObject();

Public SNMPObject()

• C#
• VB.NET

public SNMPObject(string oid);

Public SNMPObject(ByVal Oid As String)

• C#
• VB.NET

public SNMPObject(string oid, byte[] value);

Public SNMPObject(ByVal Oid As String, ByVal Value As Byte())

• C#
• VB.NET

public SNMPObject(string oid, byte[] value, SNMPObjectTypes SNMPObjectType);

Public SNMPObject(ByVal Oid As String, ByVal Value As Byte(), ByVal SNMPObjectType As SNMPObjectTypes)

Config Settings (SNMPTCPAgent Component)

SNMPTCPAgent Config Settings

TCPClient Config Settings

SSL Config Settings

-----BEGIN CERTIFICATE-----
MIIEKzCCAxOgAwIBAgIRANTET4LIkxdH6P+CFIiHvTowDQYJKoZIhvcNAQELBQAw
...
eWHV5OW1K53o/atv59sOiW5K3crjFhsBOd5Q+cJJnU+SWinPKtANXMht+EDvYY2w
F0I1XhM+pKj7FjDr+XNj
-----END CERTIFICATE-----
\r \n
-----BEGIN CERTIFICATE-----
MIIEFjCCAv6gAwIBAgIQetu1SMxpnENAnnOz1P+PtTANBgkqhkiG9w0BAQUFADBp
..
d8q23djXZbVYiIfE9ebr4g3152BlVCHZ2GyPdjhIuLeH21VbT/dyEHHA
-----END CERTIFICATE-----

-----BEGIN CERTIFICATE-----
MIIEKzCCAxOgAwIBAgIRANTET4LIkxdH6P+CFIiHvTowDQYJKoZIhvcNAQELBQAw
...
eWHV5OW1K53o/atv59sOiW5K3crjFhsBOd5Q+cJJnU+SWinPKtANXMht+EDvYY2w
F0I1XhM+pKj7FjDr+XNj
-----END CERTIFICATE-----
\r \n
-----BEGIN CERTIFICATE-----
MIIEFjCCAv6gAwIBAgIQetu1SMxpnENAnnOz1P+PtTANBgkqhkiG9w0BAQUFADBp
..
d8q23djXZbVYiIfE9ebr4g3152BlVCHZ2GyPdjhIuLeH21VbT/dyEHHA
-----END CERTIFICATE-----

Socket Config Settings

Base Config Settings

Trappable Errors (SNMPTCPAgent Component)

SNMPTCPAgent Errors

The component may also return one of the following error codes, which are inherited from other components.

TCPClient Errors

SSL Errors

TCP/IP Errors