Kerberos Component

Properties   Methods   Events   Config Settings   Errors  

The Kerberos component can be used to authenticate users using Kerberos 5.0.

Syntax

nsoftware.IPWorksAuth.Kerberos

Remarks

The Kerberos component implements the Kerberos protocol defined in RFC 1510 and RFC 4120. The component provides a simple interface to easily authenticate users.

Authentication

When Authenticate is called the component will attempt to authenticate the user with the Key Distribution Center (KDC). The component will communicate with the KDCHost to obtain a service ticket and populate AuthToken. The following properties are required when calling this method:

A typical sequence of messages would be:

  • KRB_AS_REQ -> KDC
  • KRB_AS_REP <- KDC
  • KRB_TGS_REQ -> KDC
  • KRB_TGS_REP <- KDC
  • AuthToken is populated with the constructed KRB_AP_REP message.

Communication with the KDCHost can be seen through the PITrail event.

Property List

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

AuthTokenThe authentication token.
KDCHostThe domain name or IP address of the Key Distribution Center (KDC).
KDCPortThe port for the Key Distribution Center (KDC)
KeytabFileThe Kerberos Keytab file.
PasswordThe user's password.
SPNThe Service Principal Name (SPN).
TimeoutA timeout for the component.
UserThe name and domain of the user to authenticate.
UseTCPWhether TCP is used when establishing the connection.

Method List

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

AuthenticateAuthenticates the user.
ConfigSets or retrieves a configuration setting.
DoEventsProcesses events from the internal message queue.
InterruptInterrupt the current method.
ResetResets the component properties to their default values.

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.

ErrorInformation about errors during data delivery.
LogFires once for each log message.
PITrailTraces the messages sent to the server, and the respective replies.

Config Settings

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

CredentialsCacheFileThe credentials cache file.
EncodeAuthTokenWhether to Base64 encode the AuthToken.
EncryptionTypesThe encryption types used during authentication.
LogKerberosPacketsWhether to include the raw Kerberos packets in PITrail output.
LogLevelThe level of detail that is logged.
UsePlatformKerberosAPIWhether to use the platform Kerberos API.
UseTCPWhether TCP is used when establishing the connection.
CaptureIPPacketInfoUsed to capture the packet information.
DelayHostResolutionWhether the hostname is resolved when RemoteHost is set.
DestinationAddressUsed to get the destination address from the packet information.
DontFragmentUsed to set the Don't Fragment flag of outgoing packets.
LocalHostThe name of the local host through which connections are initiated or accepted.
LocalPortThe port in the local host where the component binds.
MaxPacketSizeThe maximum length of the packets that can be received.
QOSDSCPValueUsed to specify an arbitrary QOS/DSCP setting (optional).
QOSTrafficTypeUsed to specify QOS/DSCP settings (optional).
ShareLocalPortIf set to True, allows more than one instance of the component to be active on the same local port.
UseConnectionDetermines whether to use a connected socket.
UseIPv6Whether or not to use IPv6.
AbsoluteTimeoutDetermines whether timeouts are inactivity timeouts or absolute timeouts.
FirewallDataUsed to send extra data to the firewall.
InBufferSizeThe size in bytes of the incoming queue of the socket.
OutBufferSizeThe size in bytes of the outgoing queue of the socket.
BuildInfoInformation about the product's build.
GUIAvailableTells the component whether or not a message loop is available for processing events.
LicenseInfoInformation about the current license.
MaskSensitiveWhether sensitive data is masked in log messages.
UseFIPSCompliantAPITells the component whether or not to use FIPS certified APIs.
UseInternalSecurityAPITells the component whether or not to use the system security libraries or an internal implementation.

AuthToken Property (Kerberos Component)

The authentication token.

Syntax

public string AuthToken { get; }
public byte[] AuthTokenB { get; }

Public ReadOnly Property AuthToken As String
Public ReadOnly Property AuthTokenB As Byte()

Default Value

""

Remarks

This property holds the authentication token.

This property will be populated after calling Authenticate. This may be used in by another entity to authenticate to the service. For instance this may be used in HTTP to authenticate to a web service.

The content of this property is a KRB_AP_REQ message. This is sometimes referred to as an "Authentication Header". It is comprised of the service ticket that was obtained from the TGS and an encrypted authenticator.

This property is read-only.

KDCHost Property (Kerberos Component)

The domain name or IP address of the Key Distribution Center (KDC).

Syntax

public string KDCHost { get; set; }

Public Property KDCHost As String

Default Value

""

Remarks

This property specifies the IP address (IP number in dotted internet format) or Domain Name of the Key Distribution Center (KDC).

If this property is set to a Domain Name, a DNS request is initiated and upon successful termination of the request, this property is set to the corresponding address. If the search is not successful, an error is returned.

KDCPort Property (Kerberos Component)

The port for the Key Distribution Center (KDC)

Syntax

public int KDCPort { get; set; }

Public Property KDCPort As Integer

Default Value

88

Remarks

This property specifies the port for the Key Distribution Center (KDC). The default value is 88.

KeytabFile Property (Kerberos Component)

The Kerberos Keytab file.

Syntax

public string KeytabFile { get; set; }

Public Property KeytabFile As String

Default Value

""

Remarks

This property specifies the path to a Kerberos Keytab file. If specified, the credentials are read from this file.

Password Property (Kerberos Component)

The user's password.

Syntax

public string Password { get; set; }

Public Property Password As String

Default Value

""

Remarks

This property specifies the user's password. This must be set before calling Authenticate.

SPN Property (Kerberos Component)

The Service Principal Name (SPN).

Syntax

public string SPN { get; set; }

Public Property SPN As String

Default Value

""

Remarks

This property specifies the Service Principal Name (SPN). This must be set before calling Authenticate.

Timeout Property (Kerberos Component)

A timeout for the component.

Syntax

public int Timeout { get; set; }

Public Property Timeout As Integer

Default Value

60

Remarks

If the Timeout property is set to 0, all operations will run uninterrupted until successful completion or an error condition is encountered.

If Timeout is set to a positive value, the component will wait for the operation to complete before returning control.

The component will use DoEvents to enter an efficient wait loop during any potential waiting period, making sure that all system events are processed immediately as they arrive. This ensures that the host application does not "freeze" and remains responsive.

If Timeout expires, and the operation is not yet complete, the component throws an exception.

Please note that by default, all timeouts are inactivity timeouts, i.e. the timeout period is extended by Timeout seconds when any amount of data is successfully sent or received.

The default value for the Timeout property is 60 seconds.

User Property (Kerberos Component)

The name and domain of the user to authenticate.

Syntax

public string User { get; set; }

Public Property User As String

Default Value

""

Remarks

This property specifies the name and realm/domain of the user. The value specified must be in one of the following formats:

  • user@domain
  • domain/user

UseTCP Property (Kerberos Component)

Whether TCP is used when establishing the connection.

Syntax

public bool UseTCP { get; set; }

Public Property UseTCP As Boolean

Default Value

False

Remarks

This property specifies whether TCP is used as the transport protocol when establishing the connection. By default this property is False and UDP will be used.

Authenticate Method (Kerberos Component)

Authenticates the user.

Syntax

public void Authenticate();

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

Public Sub Authenticate()

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

Remarks

This method authenticates the User.

Authentication

When Authenticate is called the component will attempt to authenticate the user with the Key Distribution Center (KDC). The component will communicate with the KDCHost to obtain a service ticket and populate AuthToken. The following properties are required when calling this method:

A typical sequence of messages would be:

  • KRB_AS_REQ -> KDC
  • KRB_AS_REP <- KDC
  • KRB_TGS_REQ -> KDC
  • KRB_TGS_REP <- KDC
  • AuthToken is populated with the constructed KRB_AP_REP message.

Communication with the KDCHost can be seen through the PITrail event.

Config Method (Kerberos Component)

Sets or retrieves a configuration setting.

Syntax

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.

DoEvents Method (Kerberos Component)

Processes events from the internal message queue.

Syntax

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.

Interrupt Method (Kerberos Component)

Interrupt the current method.

Syntax

public void Interrupt();

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

Public Sub Interrupt()

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

Remarks

If there is no method in progress, Interrupt simply returns, doing nothing.

Reset Method (Kerberos Component)

Resets the component properties to their default values.

Syntax

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

This method resets the properties to their default values.

Error Event (Kerberos Component)

Information about errors during data delivery.

Syntax

public event OnErrorHandler OnError;

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

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

Public Event OnError As OnErrorHandler

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

Public Class KerberosErrorEventArgs 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.

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

Log Event (Kerberos Component)

Fires once for each log message.

Syntax

public event OnLogHandler OnLog;

public delegate void OnLogHandler(object sender, KerberosLogEventArgs e);

public class KerberosLogEventArgs : EventArgs {
  public int LogLevel { get; }
  public string Message { get; }
  public string LogType { get; }
}

Public Event OnLog As OnLogHandler

Public Delegate Sub OnLogHandler(sender As Object, e As KerberosLogEventArgs)

Public Class KerberosLogEventArgs Inherits EventArgs
  Public ReadOnly Property LogLevel As Integer
  Public ReadOnly Property Message As String
  Public ReadOnly Property LogType As String
End Class

Remarks

This event fires once for each log message generated by the component. The verbosity is controlled by the LogLevel setting.

LogLevel indicates the level of the Message. Possible values are:

0 (None) No events are logged.
1 (Info - default) Informational events are logged.
2 (Verbose) Detailed data are logged.
3 (Debug) Debug data are logged.

The value 1 (Info) logs basic information, including the URL, HTTP version, and status details.

The value 2 (Verbose) logs additional information about the request and response.

The value 3 (Debug) logs the headers and body for both the request and response, as well as additional debug information (if any).

LogType identifies the type of log entry. Possible values are:

  • Info
  • Verbose
  • Debug

PITrail Event (Kerberos Component)

Traces the messages sent to the server, and the respective replies.

Syntax

public event OnPITrailHandler OnPITrail;

public delegate void OnPITrailHandler(object sender, KerberosPITrailEventArgs e);

public class KerberosPITrailEventArgs : EventArgs {
  public int Direction { get; }
  public string Message { get; }
}

Public Event OnPITrail As OnPITrailHandler

Public Delegate Sub OnPITrailHandler(sender As Object, e As KerberosPITrailEventArgs)

Public Class KerberosPITrailEventArgs Inherits EventArgs
  Public ReadOnly Property Direction As Integer
  Public ReadOnly Property Message As String
End Class

Remarks

The PITrail event is useful for debugging purposes. It shows all the interaction between the client and the server. To include the raw packets set LogKerberosPackets to True.

The Message parameter contains the full text of the message. The Direction parameter shows the originator of the message:

0 (Client)The Message originates from the client.
1 (Server)The Message originates from the server.
2 (Info)The Message is an informative message originating from the client software (the component code).

Config Settings (Kerberos Component)

The component accepts one or more of the following configuration settings. Configuration 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.

KERBEROS Config Settings

CredentialsCacheFile:   The credentials cache file.

This setting specifies the path to a credentials cache file. If specified, the credentials are read from this file.

EncodeAuthToken:   Whether to Base64 encode the AuthToken.

This setting specifies whether AuthToken is Base64 encoded after calling Authenticate. The default value is False.

EncryptionTypes:   The encryption types used during authentication.

This setting specifies a comma separated list of encryption types used during authentication. Possible values are:

  • rc4-hmac
  • des-cbc-md5
  • aes128-cts-hmac-sha1-96
The default value is "des-cbc-md5,rc4-hmac,aes128-cts-hmac-sha1-96".
LogKerberosPackets:   Whether to include the raw Kerberos packets in PITrail output.

This settings specifies whether to include the raw Kerberos packet in the Message parameter of the PITrail event. When True the Kerberos packet will be encoded and present in the Message parameter. The default value is False. This may be enabled for troubleshooting purposes.

LogLevel:   The level of detail that is logged.

This setting controls the level of detail that is logged through the Log event. Possible values are:

0 (None) No events are logged.
1 (Info - default) Informational events are logged.
2 (Verbose) Detailed data are logged.
3 (Debug) Debug data are logged.

The value 1 (Info) logs basic information, including the URL, HTTP version, and status details.

The value 2 (Verbose) logs additional information about the request and response.

The value 3 (Debug) logs the headers and body for both the request and response, as well as additional debug information (if any).

UsePlatformKerberosAPI:   Whether to use the platform Kerberos API.

This setting determines if the platform's Kerberos API is used. By default the component does not rely on any platform APIs to perform Kerberos authentication. Use of the platform API may be enabled by setting this to True. The default value is False.

Note: This functionality is only available on Windows.

UseTCP:   Whether TCP is used when establishing the connection.

This config specifies whether TCP is used as the transport protocol when establishing the connection. By default this config is False and UDP will be used.

UDP Config Settings

CaptureIPPacketInfo:   Used to capture the packet information.

If this is set to true, the component will capture the IP packet information.

The default value for this setting is False.

Note: This setting is only available in Windows.

DelayHostResolution:   Whether the hostname is resolved when RemoteHost is set.

This setting specifies whether a hostname is resolved immediately when RemoteHost is set. If true the component will resolve the hostname and the IP address will be present in the RemoteHost property. If false, the hostname is not resolved until needed by the component when a method to connect or send data is called. If desired, ResolveRemoteHost may called to manually resolve the value in RemoteHost at any time.

The default value is false for the default library and true for the Async library. The default value is false.

DestinationAddress:   Used to get the destination address from the packet information.

If CaptureIPPacketInfo is set to true, then this will be populated with the packet's destination address when a packet is received. This information will be accessible in the DataIn event.

Note: This setting is only available in Windows.

DontFragment:   Used to set the Don't Fragment flag of outgoing packets.

When set to True, packets sent by the component will have the Don't Fragment flag set. The default value is False.

LocalHost:   The name of the local host through which connections are initiated or accepted.

The LocalHost setting 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 setting 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).

LocalPort:   The port in the local host where the component binds.

This must be set before a connection is attempted. It instructs the component to bind to a specific port (or communication endpoint) in the local machine.

Setting this to 0 (default) enables the system to choose a port at random. The chosen port will be shown by LocalPort after the connection is established.

LocalPort cannot be changed once a connection is made. Any attempt to set this when a connection is active will generate an error.

This; setting is useful when trying to connect to services that require a trusted port in the client side. An example is the remote shell (rsh) service in UNIX systems.

MaxPacketSize:   The maximum length of the packets that can be received.

This setting specifies the maximum size of the datagrams that the component will accept without truncation.

QOSDSCPValue:   Used to specify an arbitrary QOS/DSCP setting (optional).

UseConnection must be True to use this setting. This option allows you to specify an arbitrary DSCP value between 0 and 63. The default is 0. When set to the default value the component will not set a DSCP value.

Note: This setting uses the qWAVE API is only available on Windows 7, Windows Server 2008 R2, and later.

QOSTrafficType:   Used to specify QOS/DSCP settings (optional).

UseConnection must be True to use this setting. You may specify either the text or integer values: BestEffort (0), Background (1), ExcellentEffort (2), AudioVideo (3), Voice (4), and Control (5).

Note: This setting uses the qWAVE API which is only available on Windows Vista and Windows Server 2008 or above.

Note: QOSTrafficType must be set before setting Active to true.

ShareLocalPort:   If set to True, allows more than one instance of the component to be active on the same local port.

This option must be set before the component is activated through the Active property or it will have no effect.

The default value for this setting is False.

UseConnection:   Determines whether to use a connected socket.

UseConnection specifies whether the component should use a connected socket or not. The connection is defined as an association in between the local address/port and the remote address/port. As such, this is not a connection in the traditional TCP sense. What it means is only that the component will send and receive data only to and from the specified destination.

The default value for this setting is False.

UseIPv6:   Whether or not to use IPv6.

By default, the component expects an IPv4 address for local and remote host properties, and will create an IPv4 socket. To use IPv6 instead, set this to True.

Socket Config Settings

AbsoluteTimeout:   Determines whether timeouts are inactivity timeouts or absolute timeouts.

If AbsoluteTimeout is set to True, any method which does not complete within Timeout seconds will be aborted. By default, AbsoluteTimeout is False, and the timeout is an inactivity timeout.

Note: This option is not valid for UDP ports.

FirewallData:   Used to send extra data to the firewall.

When the firewall is a tunneling proxy, use this property to send custom (additional) headers to the firewall (e.g. headers for custom authentication schemes).

InBufferSize:   The size in bytes of the incoming queue of the socket.

This is the size of an internal queue in the TCP/IP stack. You can increase or decrease its size depending on the amount of data that you will be receiving. Increasing the value of the InBufferSize setting can provide significant improvements in performance in some cases.

Some TCP/IP implementations do not support variable buffer sizes. If that is the case, when the component is activated the InBufferSize reverts to its defined size. The same happens if you attempt to make it too large or too small.

OutBufferSize:   The size in bytes of the outgoing queue of the socket.

This is the size of an internal queue in the TCP/IP stack. You can increase or decrease its size depending on the amount of data that you will be sending. Increasing the value of the OutBufferSize setting can provide significant improvements in performance in some cases.

Some TCP/IP implementations do not support variable buffer sizes. If that is the case, when the component is activated the OutBufferSize reverts to its defined size. The same happens if you attempt to make it too large or too small.

Base Config Settings

BuildInfo:   Information about the product's build.

When queried, this setting will return a string containing information about the product's build.

GUIAvailable:   Tells the component whether or not a message loop is available for processing events.

In a GUI-based application, long-running blocking operations may cause the application to stop responding to input until the operation returns. The component will attempt to discover whether or not the application has a message loop and, if one is discovered, it will process events in that message loop during any such blocking operation.

In some non-GUI applications, an invalid message loop may be discovered that will result in errant behavior. In these cases, setting GUIAvailable to false will ensure that the component does not attempt to process external events.

LicenseInfo:   Information about the current license.

When queried, this setting will return a string containing information about the license this instance of a component is using. It will return the following information:

  • Product: The product the license is for.
  • Product Key: The key the license was generated from.
  • License Source: Where the license was found (e.g., RuntimeLicense, License File).
  • License Type: The type of license installed (e.g., Royalty Free, Single Server).
  • Last Valid Build: The last valid build number for which the license will work.
MaskSensitive:   Whether sensitive data is masked in log messages.

In certain circumstances it may be beneficial to mask sensitive data, like passwords, in log messages. Set this to true to mask sensitive data. The default is true.

This setting only works on these components: AS3Receiver, AS3Sender, Atom, Client(3DS), FTP, FTPServer, IMAP, OFTPClient, SSHClient, SCP, Server(3DS), Sexec, SFTP, SFTPServer, SSHServer, TCPClient, TCPServer.

UseFIPSCompliantAPI:   Tells the component whether or not to use FIPS certified APIs.

When set to true, the component will utilize the underlying operating system's certified APIs. Java editions, regardless of OS, utilize Bouncy Castle FIPS, while all the other Windows editions make use of Microsoft security libraries.

FIPS mode can be enabled by setting the UseFIPSCompliantAPI configuration setting to true. This is a static setting which applies to all instances of all components of the toolkit within the process. It is recommended to enable or disable this setting once before the component has been used to establish a connection. Enabling FIPS while an instance of the component is active and connected may result in unexpected behavior.

For more details please see the FIPS 140-2 Compliance article.

Note: This setting is only applicable on Windows.

Note: Enabling FIPS-compliance requires a special license; please contact sales@nsoftware.com for details.

UseInternalSecurityAPI:   Tells the component whether or not to use the system security libraries or an internal implementation.

When set to false, the component will use the system security libraries by default to perform cryptographic functions where applicable. In this case, calls to unmanaged code will be made. In certain environments this is not desirable. To use a completely managed security implementation set this setting to true.

Setting this setting to true tells the component to use the internal implementation instead of using the system security libraries.

On Windows, this setting is set to false by default. On Linux/macOS, this setting is set to true by default.

If using the .NET Standard Library, this setting will be true on all platforms. The .NET Standard library does not support using the system security libraries.

Note: This setting is static. The value set is applicable to all components used in the application.

When this value is set the product's system DLL is no longer required as a reference, as all unmanaged code is stored in that file.

Trappable Errors (Kerberos Component)

kerberos Errors

950   Busy performing other action.
951   Invalid username.
952   Received error message. The error message contains the description.
953   Message integrity check error.
954   Unsupported encryption type.

UDP Errors

104   UDP is already Active.
106   You cannot change the LocalPort while the component is Active.
107   You cannot change the LocalHost at this time. A connection is in progress.
109   The component must be Active for this operation.
112   Cannot change MaxPacketSize while the component is Active.
113   Cannot change ShareLocalPort option while the component is Active.
114   Cannot change RemoteHost when UseConnection is set and the component Active.
115   Cannot change RemotePort when UseConnection is set and the component is Active.
116   RemotePort can't be zero when UseConnection is set. Please specify a valid service port number.
117   Cannot change UseConnection while the component is Active.
118   Message can't be longer than MaxPacketSize.
119   Message too short.
434   Unable to convert string to selected CodePage

TCP/IP Errors

10004   [10004] Interrupted system call.
10009   [10009] Bad file number.
10013   [10013] Access denied.
10014   [10014] Bad address.
10022   [10022] Invalid argument.
10024   [10024] Too many open files.
10035   [10035] Operation would block.
10036   [10036] Operation now in progress.
10037   [10037] Operation already in progress.
10038   [10038] Socket operation on non-socket.
10039   [10039] Destination address required.
10040   [10040] Message too long.
10041   [10041] Protocol wrong type for socket.
10042   [10042] Bad protocol option.
10043   [10043] Protocol not supported.
10044   [10044] Socket type not supported.
10045   [10045] Operation not supported on socket.
10046   [10046] Protocol family not supported.
10047   [10047] Address family not supported by protocol family.
10048   [10048] Address already in use.
10049   [10049] Can't assign requested address.
10050   [10050] Network is down.
10051   [10051] Network is unreachable.
10052   [10052] Net dropped connection or reset.
10053   [10053] Software caused connection abort.
10054   [10054] Connection reset by peer.
10055   [10055] No buffer space available.
10056   [10056] Socket is already connected.
10057   [10057] Socket is not connected.
10058   [10058] Can't send after socket shutdown.
10059   [10059] Too many references, can't splice.
10060   [10060] Connection timed out.
10061   [10061] Connection refused.
10062   [10062] Too many levels of symbolic links.
10063   [10063] File name too long.
10064   [10064] Host is down.
10065   [10065] No route to host.
10066   [10066] Directory not empty
10067   [10067] Too many processes.
10068   [10068] Too many users.
10069   [10069] Disc Quota Exceeded.
10070   [10070] Stale NFS file handle.
10071   [10071] Too many levels of remote in path.
10091   [10091] Network subsystem is unavailable.
10092   [10092] WINSOCK DLL Version out of range.
10093   [10093] Winsock not loaded yet.
11001   [11001] Host not found.
11002   [11002] Non-authoritative 'Host not found' (try again or check DNS setup).
11003   [11003] Non-recoverable errors: FORMERR, REFUSED, NOTIMP.
11004   [11004] Valid name, no data record (check DNS setup).