SNMPAgent Module

Properties   Methods   Events   Config Settings   Errors  

The SNMPAgent module is used to implement UDP-based SNMP Agent Applications.

Syntax

IPWorksSNMP.Snmpagent

Remarks

The SNMPAgent class implements a UDP-based standard SNMP Agent as specified in the SNMP RFCs. The class supports SNMP v1, v2c, and v3.

The class 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 class 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 class 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 module with short descriptions. Click on the links for further details.

Method List

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

Event List

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

Config Settings

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

AcceptData Property (SNMPAgent Module)

Enables or disables data reception.

Syntax

• Swift
• Objective-C

public var acceptData: Bool {
  get {...}
  set {...}
}

@property (nonatomic,readwrite,assign,getter=acceptData,setter=setAcceptData:) BOOL acceptData;

- (BOOL)acceptData;
- (void)setAcceptData :(BOOL)newAcceptData;

Default Value

True

Remarks

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

Active Property (SNMPAgent Module)

Indicates whether the module is active.

Syntax

• Swift
• Objective-C

public var active: Bool {
  get {...}
  set {...}
}

@property (nonatomic,readwrite,assign,getter=active,setter=setActive:) BOOL active;

- (BOOL)active;
- (void)setActive :(BOOL)newActive;

Default Value

False

Remarks

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

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

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

LocalEngineId Property (SNMPAgent Module)

The Engine Id of the SNMP Agent.

Syntax

• Swift
• Objective-C

public var localEngineId: String {
  get {...}
  set {...}
}

public var localEngineIdB: Data {
  get {...}
  set {...}
}

@property (nonatomic,readwrite,assign,getter=localEngineId,setter=setLocalEngineId:) NSString* localEngineId;

- (NSString*)localEngineId;
- (void)setLocalEngineId :(NSString*)newLocalEngineId;

@property (nonatomic,readwrite,assign,getter=localEngineIdB,setter=setLocalEngineIdB:) NSData* localEngineIdB;

- (NSData*)localEngineIdB;
- (void)setLocalEngineIdB :(NSData*)newLocalEngineId;

Default Value

""

Remarks

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

LocalHost Property (SNMPAgent Module)

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

Syntax

• Swift
• Objective-C

public var localHost: String {
  get {...}
  set {...}
}

@property (nonatomic,readwrite,assign,getter=localHost,setter=setLocalHost:) NSString* localHost;

- (NSString*)localHost;
- (void)setLocalHost :(NSString*)newLocalHost;

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 class initiate connections (or accept in the case of server classs) only through that interface.

If the class 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 (SNMPAgent Module)

The port in the local host where the module listens.

Syntax

• Swift
• Objective-C

public var localPort: Int32 {
  get {...}
  set {...}
}

@property (nonatomic,readwrite,assign,getter=localPort,setter=setLocalPort:) int localPort;

- (int)localPort;
- (void)setLocalPort :(int)newLocalPort;

Default Value

161

Remarks

The LocalPort property must be set before the class is activated (Active is set to True). It instructs the class 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 class is activated through the Active property.

LocalPort cannot be changed once the class is Active. Any attempt to set the LocalPort property when the class 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 (SNMPAgent Module)

The objects in the current request.

Syntax

• Swift
• Objective-C

public var objects: Array<SNMPObject> {
  get {...}
}

@property (nonatomic,readwrite,assign,getter=objCount,setter=setObjCount:) int objCount;

- (int)objCount;
- (void)setObjCount :(int)newObjCount;

- (int)objType:(int)objIndex;
- (void)setObjType:(int)objIndex :(int)newObjType;

- (NSString*)objId:(int)objIndex;
- (void)setObjId:(int)objIndex :(NSString*)newObjId;

- (NSString*)objTypeString:(int)objIndex;

- (NSString*)objValue:(int)objIndex;
- (void)setObjValue:(int)objIndex :(NSString*)newObjValue;

- (NSData*)objValueB:(int)objIndex;
- (void)setObjValueB:(int)objIndex :(NSData*)newObjValue;

Default Value

0

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.

RequestId Property (SNMPAgent Module)

The request-id to mark outgoing packets with.

Syntax

• Swift
• Objective-C

public var requestId: Int32 {
  get {...}
  set {...}
}

@property (nonatomic,readwrite,assign,getter=requestId,setter=setRequestId:) int requestId;

- (int)requestId;
- (void)setRequestId :(int)newRequestId;

Default Value

1

Remarks

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

SNMPVersion Property (SNMPAgent Module)

Version of SNMP used for outgoing requests (traps).

Syntax

• Swift
• Objective-C

public var snmpVersion: SnmpagentSNMPVersions {
  get {...}
  set {...}
}

public enum SnmpagentSNMPVersions: Int32 {
  case snmpverV1 = 1
  case snmpverV2c = 2
  case snmpverV3 = 3
}

@property (nonatomic,readwrite,assign,getter=SNMPVersion,setter=setSNMPVersion:) int SNMPVersion;

- (int)SNMPVersion;
- (void)setSNMPVersion :(int)newSNMPVersion;

Default Value

2

Remarks

This property takes one of the following values:

SysUpTime Property (SNMPAgent Module)

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

Syntax

• Swift
• Objective-C

public var sysUpTime: Int64 {
  get {...}
  set {...}
}

@property (nonatomic,readwrite,assign,getter=sysUpTime,setter=setSysUpTime:) long long sysUpTime;

- (long long)sysUpTime;
- (void)setSysUpTime :(long long)newSysUpTime;

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.

Activate Method (SNMPAgent Module)

Activates the component.

Syntax

• Swift
• Objective-C

public func activate() throws -> Void

- (void)activate;

Remarks

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

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

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

AddUser Method (SNMPAgent Module)

Adds a user to the internal authentication cache.

Syntax

• Swift
• Objective-C

public func addUser(user: String, authenticationProtocol: Int32, authenticationPassword: String, encryptionAlgorithm: Int32, encryptionPassword: String) throws -> Void

- (void)addUser:(NSString*)user :(int)authenticationProtocol :(NSString*)authenticationPassword :(int)encryptionAlgorithm :(NSString*)encryptionPassword;

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 class will attempt to verify users with all valid authentication protocols.

ClearCache Method (SNMPAgent Module)

Clears the internal authentication database.

Syntax

• Swift
• Objective-C

public func clearCache() throws -> Void

- (void)clearCache;

Remarks

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

Config Method (SNMPAgent Module)

Sets or retrieves a configuration setting.

Syntax

• Swift
• Objective-C

public func config(configurationString: String) throws -> String

- (NSString*)config:(NSString*)configurationString;

Remarks

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

These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the class, 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 (SNMPAgent Module)

Deactivates the component.

Syntax

• Swift
• Objective-C

public func deactivate() throws -> Void

- (void)deactivate;

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 (SNMPAgent Module)

Processes events from the internal message queue.

Syntax

• Swift
• Objective-C

public func doEvents() throws -> Void

- (void)doEvents;

Remarks

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

HashPasswords Method (SNMPAgent Module)

Hashes all passwords in the cache.

Syntax

• Swift
• Objective-C

public func hashPasswords() throws -> Void

- (void)hashPasswords;

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 (SNMPAgent Module)

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

Syntax

• Swift
• Objective-C

public func removeUser(user: String) throws -> Void

- (void)removeUser:(NSString*)user;

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 (SNMPAgent Module)

Clears the object arrays.

Syntax

• Swift
• Objective-C

public func reset() throws -> Void

- (void)reset;

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 (SNMPAgent Module)

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

Syntax

• Swift
• Objective-C

public func sendResponse(remoteHost: String, remotePort: Int32, requestId: Int32, community: String, errorStatus: Int32, errorIndex: Int32) throws -> Void

- (void)sendResponse:(NSString*)remoteHost :(int)remotePort :(int)requestId :(NSString*)community :(int)errorStatus :(int)errorIndex;

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 (SNMPAgent Module)

Sends an authenticated and/or encrypted SNMPv3 response.

Syntax

• Swift
• Objective-C

public func sendSecureResponse(remoteHost: String, remotePort: Int32, requestId: Int32, messageId: Int32, errorStatus: Int32, errorIndex: Int32, user: String, authenticationProtocol: Int32, authenticationPassword: String, encryptionAlgorithm: Int32, encryptionPassword: String) throws -> Void

- (void)sendSecureResponse:(NSString*)remoteHost :(int)remotePort :(int)requestId :(int)messageId :(int)errorStatus :(int)errorIndex :(NSString*)user :(int)authenticationProtocol :(NSString*)authenticationPassword :(int)encryptionAlgorithm :(NSString*)encryptionPassword;

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 (SNMPAgent Module)

Sends an authenticated and/or encrypted SNMPv3 trap.

Syntax

• Swift
• Objective-C

public func sendSecureTrap(remoteHost: String, trapOID: String, user: String, authenticationProtocol: Int32, authenticationPassword: String, encryptionAlgorithm: Int32, encryptionPassword: String) throws -> Void

- (void)sendSecureTrap:(NSString*)remoteHost :(NSString*)trapOID :(NSString*)user :(int)authenticationProtocol :(NSString*)authenticationPassword :(int)encryptionAlgorithm :(NSString*)encryptionPassword;

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 (SNMPAgent Module)

Sends an SNMP Trap.

Syntax

• Swift
• Objective-C

public func sendTrap(remoteHost: String, trapOID: String) throws -> Void

- (void)sendTrap:(NSString*)remoteHost :(NSString*)trapOID;

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 (SNMPAgent Module)

Lists all entries in the internal user authentication cache.

Syntax

• Swift
• Objective-C

public func showCache() throws -> Void

- (void)showCache;

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 (SNMPAgent Module)

Returns the value corresponding to an OID.

Syntax

• Swift
• Objective-C

public func value(oid: String) throws -> String

- (NSString*)value:(NSString*)OID;

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 (SNMPAgent Module)

Fired for erroneous and/or malformed messages.

Syntax

• Swift
• Objective-C

func onBadPacket(packet: Data, sourceAddress: String, sourcePort: Int32, errorCode: Int32, errorDescription: String, report: inout Bool)

- (void)onBadPacket:(NSData*)packet :(NSString*)sourceAddress :(int)sourcePort :(int)errorCode :(NSString*)errorDescription :(int*)report;

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 (SNMPAgent Module)

Shows in the internal cache.

Syntax

• Swift
• Objective-C

func onCacheEntry(user: String, authenticationProtocol: String, authenticationPassword: String, encryptionAlgorithm: String, encryptionPassword: String)

- (void)onCacheEntry:(NSString*)user :(NSString*)authenticationProtocol :(NSString*)authenticationPassword :(NSString*)encryptionAlgorithm :(NSString*)encryptionPassword;

Remarks

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

DiscoveryRequest Event (SNMPAgent Module)

Fired when an SNMPv3 discovery packet is received.

Syntax

• Swift
• Objective-C

func onDiscoveryRequest(engineId: Data, engineBoots: Int32, engineTime: Int32, user: String, securityLevel: Int32, sourceAddress: String, sourcePort: Int32, respond: inout Bool)

- (void)onDiscoveryRequest:(NSData*)engineId :(int)engineBoots :(int)engineTime :(NSString*)user :(int)securityLevel :(NSString*)sourceAddress :(int)sourcePort :(int*)respond;

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 (SNMPAgent Module)

Fired when information is available about errors during data delivery.

Syntax

• Swift
• Objective-C

func onError(errorCode: Int32, description: String)

- (void)onError:(int)errorCode :(NSString*)description;

Remarks

The Error event is fired in case of exceptional conditions during message processing. Normally the class .

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 (SNMPAgent Module)

Fired when a GetBulkRequest packet is received.

Syntax

• Swift
• Objective-C

func onGetBulkRequest(requestId: Int32, messageId: Int32, snmpVersion: Int32, community: String, user: String, securityLevel: Int32, sourceAddress: String, sourcePort: Int32, nonRepeaters: Int32, maxRepetitions: Int32, errorIndex: inout Int32, errorStatus: inout Int32, errorDescription: String, respond: inout Bool)

- (void)onGetBulkRequest:(int)requestId :(int)messageId :(int)SNMPVersion :(NSString*)community :(NSString*)user :(int)securityLevel :(NSString*)sourceAddress :(int)sourcePort :(int)nonRepeaters :(int)maxRepetitions :(int*)errorIndex :(int*)errorStatus :(NSString*)errorDescription :(int*)respond;

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 ObjectsOid, ObjectsObjectType, and ObjectsValue 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 (SNMPAgent Module)

Fired when a GetNextRequest packet is received.

Syntax

• Swift
• Objective-C

func onGetNextRequest(requestId: Int32, messageId: Int32, snmpVersion: Int32, community: String, user: String, securityLevel: Int32, sourceAddress: String, sourcePort: Int32, errorIndex: inout Int32, errorStatus: inout Int32, errorDescription: String, respond: inout Bool)

- (void)onGetNextRequest:(int)requestId :(int)messageId :(int)SNMPVersion :(NSString*)community :(NSString*)user :(int)securityLevel :(NSString*)sourceAddress :(int)sourcePort :(int*)errorIndex :(int*)errorStatus :(NSString*)errorDescription :(int*)respond;

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 ObjectsOid, ObjectsObjectType, and ObjectsValue 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 (SNMPAgent Module)

Fired when a GetRequest packet is received.

Syntax

• Swift
• Objective-C

func onGetRequest(requestId: Int32, messageId: Int32, snmpVersion: Int32, community: String, user: String, securityLevel: Int32, sourceAddress: String, sourcePort: Int32, errorIndex: inout Int32, errorStatus: inout Int32, errorDescription: String, respond: inout Bool)

- (void)onGetRequest:(int)requestId :(int)messageId :(int)SNMPVersion :(NSString*)community :(NSString*)user :(int)securityLevel :(NSString*)sourceAddress :(int)sourcePort :(int*)errorIndex :(int*)errorStatus :(NSString*)errorDescription :(int*)respond;

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 ObjectsOid, ObjectsObjectType, and ObjectsValue 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 (SNMPAgent Module)

Retrieves a password associated with a user.

Syntax

• Swift
• Objective-C

func onGetUserPassword(passwordType: Int32, user: String, password: inout String, algorithm: inout Int32)

- (void)onGetUserPassword:(int)passwordType :(NSString*)user :(NSString**)password :(int*)algorithm;

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 (SNMPAgent Module)

Sets the security level for an incoming packet.

Syntax

• Swift
• Objective-C

func onGetUserSecurityLevel(user: String, engineId: Data, securityLevel: inout Int32)

- (void)onGetUserSecurityLevel:(NSString*)user :(NSData*)engineId :(int*)securityLevel;

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 (SNMPAgent Module)

Fired before and after a password is hashed.

Syntax

• Swift
• Objective-C

func onHashPassword(password: String, authAlgorithm: Int32, hash: inout String)

- (void)onHashPassword:(NSString*)password :(int)authAlgorithm :(NSString**)hash;

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 class 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 (SNMPAgent Module)

Fired for every packet sent or received.

Syntax

• Swift
• Objective-C

func onPacketTrace(packet: Data, direction: Int32, packetAddress: String, packetPort: Int32)

- (void)onPacketTrace:(NSData*)packet :(int)direction :(NSString*)packetAddress :(int)packetPort;

Remarks

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

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 (SNMPAgent Module)

Fired when the component is ready to send data.

Syntax

• Swift
• Objective-C

func onReadyToSend()

- (void)onReadyToSend;

Remarks

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

Report Event (SNMPAgent Module)

Fired when a Report packet is received.

Syntax

• Swift
• Objective-C

func onReport(requestId: Int32, snmpVersion: Int32, community: String, user: String, securityLevel: Int32, sourceAddress: String, sourcePort: Int32, errorIndex: Int32, errorStatus: Int32, errorDescription: String)

- (void)onReport:(int)requestId :(int)SNMPVersion :(NSString*)community :(NSString*)user :(int)securityLevel :(NSString*)sourceAddress :(int)sourcePort :(int)errorIndex :(int)errorStatus :(NSString*)errorDescription;

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 ObjectsOid, ObjectsObjectType, and ObjectsValue 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 (SNMPAgent Module)

Fired when a SetRequest packet is received.

Syntax

• Swift
• Objective-C

func onSetRequest(requestId: Int32, messageId: Int32, snmpVersion: Int32, community: String, user: String, securityLevel: Int32, sourceAddress: String, sourcePort: Int32, errorIndex: inout Int32, errorStatus: inout Int32, errorDescription: String, respond: inout Bool)

- (void)onSetRequest:(int)requestId :(int)messageId :(int)SNMPVersion :(NSString*)community :(NSString*)user :(int)securityLevel :(NSString*)sourceAddress :(int)sourcePort :(int*)errorIndex :(int*)errorStatus :(NSString*)errorDescription :(int*)respond;

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 ObjectsOid, ObjectsObjectType, and ObjectsValue 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).

SNMPObject Type

The current SNMP object.

Remarks

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

Fields

Constructors

public init()

public init(oid: )

public init(oid: , value: )

Config Settings (SNMPAgent Module)

SNMPAgent Config Settings

UDP Config Settings

Socket Config Settings

Base Config Settings

Trappable Errors (SNMPAgent Module)

SNMPAgent Errors

UDP Errors

SSL Errors

TCP/IP Errors