SNMPTrapMgr Component

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The SNMPTrapMgr component provides a UDP-based listening point for SNMP traps.

Syntax

nsoftware.IPWorksSNMP.Snmptrapmgr

Remarks

The SNMPTrapMgr component provides a UDP-based listening point for SNMP traps and informs as specified by the SNMP RFCs. The component supports v1, v2c, and v3 traps.

The component provides both encoding/decoding and transport capabilities, making the task of developing a custom SNMP Trap manager as simple as setting a few key properties and handling a few events. SNMP data, such as for instance 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.

Messages are received through events such as Trap, InformRequest, or DiscoveryRequest.

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

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 AddUser, RemoveUser, ShowCache, ClearCache, AddEngine, and RemoveEngine 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.

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 (SNMPTrapMgr 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 (SNMPTrapMgr 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 (SNMPTrapMgr Component)

The Engine Id (for SNMPv3).

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 necessary for properly handling InformRequest packets.

LocalHost Property (SNMPTrapMgr 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 (SNMPTrapMgr Component)

The port in the local host where the component is bound to.

Syntax

• C#
• VB.NET

public int LocalPort { get; set; }

Public Property LocalPort As Integer

Default Value

162

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.

The default port is 162 (standard trap port). If that port is busy, an error will be returned, unless the ForceLocalPort configuration setting is set to False, in which case a random port will be chosen.

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 (SNMPTrapMgr 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 (SNMPTrapMgr 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.

Activate Method (SNMPTrapMgr 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.

AddEngine Method (SNMPTrapMgr Component)

Adds the engine specified by EngineId to the internal authentication cache.

Syntax

• C#
• VB.NET

public void AddEngine(byte[] engineId, int engineBoots, int engineTime);

Async Version
public async Task AddEngine(byte[] engineId, int engineBoots, int engineTime);
public async Task AddEngine(byte[] engineId, int engineBoots, int engineTime, CancellationToken cancellationToken);

Public Sub AddEngine(ByVal EngineId As String, ByVal EngineBoots As Integer, ByVal EngineTime As Integer)

Async Version
Public Sub AddEngine(ByVal EngineId As String, ByVal EngineBoots As Integer, ByVal EngineTime As Integer) As Task
Public Sub AddEngine(ByVal EngineId As String, ByVal EngineBoots As Integer, ByVal EngineTime As Integer, 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.

If the engine parameters are unknown, the SNMPMgr component's Discover method can be used to perform a discovery with the agent. The RemoteEngineId, RemoteEngineTime, and RemoteEngineBoots properties will hold the values that can then be passed to this method.

AddUser Method (SNMPTrapMgr Component)

Adds a user for the engine specified by EngineId to the internal authentication cache.

Syntax

• C#
• VB.NET

public void AddUser(string user, byte[] engineId, int authenticationProtocol, string authenticationPassword, int encryptionAlgorithm, string encryptionPassword);

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

Public Sub AddUser(ByVal User As String, ByVal EngineId 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 EngineId 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 EngineId 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:

ClearCache Method (SNMPTrapMgr 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 and engine records are removed from the internal authentication cache as a result of this call.

Config Method (SNMPTrapMgr 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 (SNMPTrapMgr 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 (SNMPTrapMgr 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 (SNMPTrapMgr 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.

RemoveEngine Method (SNMPTrapMgr Component)

Removes the engine specified by EngineId from the internal authentication cache.

Syntax

• C#
• VB.NET

public void RemoveEngine(byte[] engineId);

Async Version
public async Task RemoveEngine(byte[] engineId);
public async Task RemoveEngine(byte[] engineId, CancellationToken cancellationToken);

Public Sub RemoveEngine(ByVal EngineId As String)

Async Version
Public Sub RemoveEngine(ByVal EngineId As String) As Task
Public Sub RemoveEngine(ByVal EngineId 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.

RemoveUser Method (SNMPTrapMgr Component)

Removes the user specified by User of the engine specified by EngineId from the internal authentication cache.

Syntax

• C#
• VB.NET

public void RemoveUser(string user, byte[] engineId);

Async Version
public async Task RemoveUser(string user, byte[] engineId);
public async Task RemoveUser(string user, byte[] engineId, CancellationToken cancellationToken);

Public Sub RemoveUser(ByVal User As String, ByVal EngineId As String)

Async Version
Public Sub RemoveUser(ByVal User As String, ByVal EngineId As String) As Task
Public Sub RemoveUser(ByVal User As String, ByVal EngineId 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 (SNMPTrapMgr 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).

ShowCache Method (SNMPTrapMgr Component)

Lists all entries in the internal user and engine database.

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 database.

Value Method (SNMPTrapMgr 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 (SNMPTrapMgr Component)

Fired for erroneous and/or malformed messages.

Syntax

• C#
• VB.NET

public event OnBadPacketHandler OnBadPacket;

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

public class SnmptrapmgrBadPacketEventArgs : 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 SnmptrapmgrBadPacketEventArgs)

Public Class SnmptrapmgrBadPacketEventArgs 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 (SNMPTrapMgr Component)

Shows engines and users in the internal cache.

Syntax

• C#
• VB.NET

public event OnCacheEntryHandler OnCacheEntry;

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

public class SnmptrapmgrCacheEntryEventArgs : EventArgs {
  public string EngineId { get; }
  public byte[] EngineIdB { get; }
  public int EngineBoots { get; }
  public int EngineTime { get; }
  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 SnmptrapmgrCacheEntryEventArgs)

Public Class SnmptrapmgrCacheEntryEventArgs 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 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 and engine. If there are no users for a particular engine, a single event is fired with the engine information, but empty values for user information.

CheckEngine Event (SNMPTrapMgr Component)

Fired to check engine parameters (timeliness, etc.).

Syntax

• C#
• VB.NET

public event OnCheckEngineHandler OnCheckEngine;

public delegate void OnCheckEngineHandler(object sender, SnmptrapmgrCheckEngineEventArgs e);

public class SnmptrapmgrCheckEngineEventArgs : 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 RemoteAddress { get; }
  public int RemotePort { get; }
  public bool IsNew { get; }
  public bool Accept { get; set; }
}

Public Event OnCheckEngine As OnCheckEngineHandler

Public Delegate Sub OnCheckEngineHandler(sender As Object, e As SnmptrapmgrCheckEngineEventArgs)

Public Class SnmptrapmgrCheckEngineEventArgs 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 RemoteAddress As String
  Public ReadOnly Property RemotePort As Integer
  Public ReadOnly Property IsNew As Boolean
  Public Property Accept As Boolean
End Class

Remarks

The Accept parameter determines if the engine will be accepted or not. If you set Accept to False prior to exiting the event, the processing on the message will stop and a BadPacket event will be fired.

The default value of Accept is True if and only if:

a) the engine already exists in the internal authentication cache (the IsNew parameter is False) and the timeliness has been verified;

b) the engine does not exist in the internal authentication cache (the IsNew parameter is True), but the packet has been authenticated by the component (SecurityLevel >= 1).

In all other cases, the default value for Accept is False, and you are responsible for accepting or not accepting the engine based on other considerations.

If Accept is true upon event exit, then:

a) if the engine already exists in the internal authentication cache, its time is updated to reflect the new time and the processing of the packet continues;

b) if the engine does not exist in the internal authentication cache, it is added there and if User is authenticated, the User will be added too.

DiscoveryRequest Event (SNMPTrapMgr Component)

Fired when an SNMPv3 discovery packet is received.

Syntax

• C#
• VB.NET

public event OnDiscoveryRequestHandler OnDiscoveryRequest;

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

public class SnmptrapmgrDiscoveryRequestEventArgs : 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 SnmptrapmgrDiscoveryRequestEventArgs)

Public Class SnmptrapmgrDiscoveryRequestEventArgs 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 (SNMPTrapMgr 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, SnmptrapmgrErrorEventArgs e);

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

Public Event OnError As OnErrorHandler

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

Public Class SnmptrapmgrErrorEventArgs 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.

GetUserPassword Event (SNMPTrapMgr Component)

Retrieves a password associated with a user.

Syntax

• C#
• VB.NET

public event OnGetUserPasswordHandler OnGetUserPassword;

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

public class SnmptrapmgrGetUserPasswordEventArgs : EventArgs {
  public int PasswordType { get; }
  public string User { get; }
  public string EngineId { get; }
  public byte[] EngineIdB { 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 SnmptrapmgrGetUserPasswordEventArgs)

Public Class SnmptrapmgrGetUserPasswordEventArgs Inherits EventArgs
  Public ReadOnly Property PasswordType As Integer
  Public ReadOnly Property User As String
  Public ReadOnly Property EngineId As String
  Public ReadOnly Property EngineIdB As Byte()
  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 and EngineId 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 (SNMPTrapMgr Component)

Sets the security level for an incoming packet.

Syntax

• C#
• VB.NET

public event OnGetUserSecurityLevelHandler OnGetUserSecurityLevel;

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

public class SnmptrapmgrGetUserSecurityLevelEventArgs : 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 SnmptrapmgrGetUserSecurityLevelEventArgs)

Public Class SnmptrapmgrGetUserSecurityLevelEventArgs 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 (SNMPTrapMgr Component)

Fired before and after a password is hashed.

Syntax

• C#
• VB.NET

public event OnHashPasswordHandler OnHashPassword;

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

public class SnmptrapmgrHashPasswordEventArgs : 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 SnmptrapmgrHashPasswordEventArgs)

Public Class SnmptrapmgrHashPasswordEventArgs 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

InformRequest Event (SNMPTrapMgr Component)

Fired when an InformRequest packet is received.

Syntax

• C#
• VB.NET

public event OnInformRequestHandler OnInformRequest;

public delegate void OnInformRequestHandler(object sender, SnmptrapmgrInformRequestEventArgs e);

public class SnmptrapmgrInformRequestEventArgs : 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; set; }
  public int ErrorStatus { get; set; }
  public string ErrorDescription { get; }
  public bool Respond { get; set; }
}

Public Event OnInformRequest As OnInformRequestHandler

Public Delegate Sub OnInformRequestHandler(sender As Object, e As SnmptrapmgrInformRequestEventArgs)

Public Class SnmptrapmgrInformRequestEventArgs 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 Property ErrorIndex As Integer
  Public Property ErrorStatus As Integer
  Public ReadOnly Property ErrorDescription As String
  Public Property Respond As Boolean
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 user in an InformRequest packet (SNMPv3) must be a valid user in the internal authentication cache (see the AddUser method and the CheckEngine event for more information). If not, the request is rejected, and a BadPacket event is fired before InformRequest is fired.

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).

PacketTrace Event (SNMPTrapMgr Component)

Fired for every packet sent or received.

Syntax

• C#
• VB.NET

public event OnPacketTraceHandler OnPacketTrace;

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

public class SnmptrapmgrPacketTraceEventArgs : 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 SnmptrapmgrPacketTraceEventArgs)

Public Class SnmptrapmgrPacketTraceEventArgs 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.

Trap Event (SNMPTrapMgr Component)

Fired when a SNMP trap packet is received.

Syntax

• C#
• VB.NET

public event OnTrapHandler OnTrap;

public delegate void OnTrapHandler(object sender, SnmptrapmgrTrapEventArgs e);

public class SnmptrapmgrTrapEventArgs : EventArgs {
  public int RequestId { get; }
  public int SNMPVersion { get; }
  public string Community { get; }
  public string User { get; }
  public int SecurityLevel { get; }
  public string TrapOID { get; }
  public long TimeStamp { get; }
  public string AgentAddress { get; }
  public string SourceAddress { get; }
  public int SourcePort { get; }
}

Public Event OnTrap As OnTrapHandler

Public Delegate Sub OnTrapHandler(sender As Object, e As SnmptrapmgrTrapEventArgs)

Public Class SnmptrapmgrTrapEventArgs 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 TrapOID As String
  Public ReadOnly Property TimeStamp As Long
  Public ReadOnly Property AgentAddress As String
  Public ReadOnly Property SourceAddress As String
  Public ReadOnly Property SourcePort As Integer
End Class

Remarks

The TrapOID and TimeStamp parameters contain the Trap OID and TimeStamp. In the case of an SNMPv1 trap, there are two possible scenarios:

First, if the enterprise of the trap is "1.3.6.1.6.3.1.1.5", TrapOID will be a concatenation of TrapEnterprise and GenericTrap + 1. For instance a TrapOID of "1.3.6.1.6.3.1.1.5.5" has a TrapEnterprise of "1.3.6.1.6.3.1.1.5" and a GenericTrap of "4".

Second, In all other cases TrapOID will be a concatenation of the values for TrapEnterprise, GenericTrap, and SpecificTrap, separated by '.'.

For SNMPv2 and above, they are read from the variable-value list (if available).

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.

Some parameters are only applicable depending on the SNMPVersion value. The table below shows which parameters are applicable to which SNMP versions.

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 (SNMPTrapMgr Component)

SNMPTrapMgr Config Settings

UDP Config Settings

Socket Config Settings

Base Config Settings

Trappable Errors (SNMPTrapMgr Component)

SNMPTrapMgr Errors

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

UDP Errors

SSL Errors

TCP/IP Errors