SSHReverseTunnel Component

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The SSHReverseTunnel component provides a simple way to establish a reverse tunnel with an SSH host.

Syntax

TiphSSHReverseTunnel

Remarks

The SSHReverseTunnel component may be used to establish a reverse tunnel with an SSH host. The SSH host will listen for incoming connections on the specified port and forward traffic to the component through the SSH tunnel.

The SSHHost and SSHPort properties specify the SSH server to use. The SSHUser and SSHPassword properties allow the client to authenticate itself with the server. The SSHServerAuthentication event and/or SSHAcceptServerHostKey property allow you to check the server identity. Finally, the SSHStatus event provides information about the SSH handshake.

To begin, call SSHLogon to connect to the SSH host. After this method returns, the connection to the SSH server is successfully established. Call RequestForwarding to establish a reverse tunnel. This method takes parameters to tell the SSH host on which port to listen.

The component has two modes that allow data to be dealt with directly from the events, or automatically forwarded on to a different endpoint.

Event Based Operation

In this mode, any data received by the component over the tunnel causes the events of the component to fire. For instance:

SSHReverseTunnel.RequestForwarding("0.0.0.0", 777, "", 0);

In the above code, forwarding is requested from port 777 on the SSHHost. Any data received on port 777 by the SSHHost will be sent to the component. In the above code, the last two parameters are empty and 0, indicating to the component that no local forwarding is requested.

Once RequestForwarding returns, the SSH reverse tunnel is established. Any connection made to the SSH host on the specified port will then trigger the component's events to fire, allowing you to handle the connection request and data.

When a client connects to the SSH host on the specified port, the SSHChannelOpenRequest event will fire. Within this event, choose to accept or reject the connection by setting the Accept parameter. This event contains details about the connection that may be used when determining whether to accept the connection.

After the channel is established, data is received through the SSHChannelData event. Call the SendChannelData method to send data over the channel, and call the CloseChannel method to close the channel.

Local Forwarding

In this mode, any data received by the component is automatically forwarded to a separate endpoint. This allows the component to act as a sort of proxy. There is no need to handle data directly in this case. For instance: SSHReverseTunnel.RequestForwarding("0.0.0.0", 777, "nsoftware.com", 80);

In the above code, forwarding is requested from port 777 on SSHHost. The component is instructed to establish a connection to "nsoftware.com" on port 80 when a client connects to SSHHost on port 777. Any data received from the client connected to SSHHost on port 777 will automatically be forwarded to "nsoftware.com" on port 80. Any data received back from "nsoftware.com" on port 80 will be sent back to the connected client.

In this mode, data may flow freely from the client connected to the SSHHost to the endpoint specified in the RequestForwarding method without any additional code required.

Additional Notes

The following events are applicable when a connection is made to the SSH host:

• SSHChannelClosed
• SSHChannelData
• SSHChannelEOF
• SSHChannelOpened
• SSHChannelOpenRequest
• SSHChannelReadyToSend
• SSHChannelRequested

To stop a previously established reverse tunnel, call the CancelForwarding method.

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.

SSHChannelCount Property (SSHReverseTunnel Component)

The number of records in the arrays.

Syntax

__property int SSHChannelCount = { read=FSSHChannelCount };

Default Value

0

Remarks

This property controls the size of the following arrays:

• BytesSent
• ChannelId
• ConnectedAddress
• ConnectedPort
• DataToSend
• FirewallAutoDetect
• FirewallHost
• FirewallPassword
• FirewallPort
• FirewallType
• FirewallUser
• ForwardingHost
• ForwardingPort
• OriginAddress
• OriginPort
• Service
• SSHAcceptServerHostKeyEncoded
• SSHCertEncoded
• SSHCertStore
• SSHCertStorePassword
• SSHCertStoreType
• SSHCertSubject

The array indices start at 0 and end at SSHChannelCount - 1.

This property is read-only and not available at design time.

Data Type

Integer

BytesSent Property (SSHReverseTunnel Component)

The number of bytes actually sent after a sending channel data.

Syntax

__property int BytesSent[int SSHChannelId] = { read=FBytesSent };

Default Value

0

Remarks

The number of bytes actually sent after a sending channel data.

The SSHChannelId parameter specifies the index of the item in the array. The size of the array is controlled by the SSHChannelCount property.

This property is read-only and not available at design time.

Data Type

Integer

ChannelId Property (SSHReverseTunnel Component)

An id generated by the component to identify the current SSH channel.

Syntax

__property String ChannelId[int SSHChannelId] = { read=FChannelId };

Default Value

""

Remarks

An id generated by the component to identify the current SSH channel. This id is unique to this channel.

The SSHChannelId parameter specifies the index of the item in the array. The size of the array is controlled by the SSHChannelCount property.

This property is read-only and not available at design time.

Data Type

String

ConnectedAddress Property (SSHReverseTunnel Component)

This property holds the remote address to which the connection was established.

Syntax

__property String ConnectedAddress[int SSHChannelId] = { read=FConnectedAddress };

Default Value

""

Remarks

This property holds the remote address to which the connection was established. This should match the Address parameter passed to the RequestForwarding method.

The SSHChannelId parameter specifies the index of the item in the array. The size of the array is controlled by the SSHChannelCount property.

This property is read-only and not available at design time.

Data Type

String

ConnectedPort Property (SSHReverseTunnel Component)

This property holds the remote port to which the connection was established.

Syntax

__property int ConnectedPort[int SSHChannelId] = { read=FConnectedPort };

Default Value

0

Remarks

This property holds the remote port to which the connection was established. This should match the Port parameter passed to the RequestForwarding method.

The SSHChannelId parameter specifies the index of the item in the array. The size of the array is controlled by the SSHChannelCount property.

This property is read-only and not available at design time.

Data Type

Integer

DataToSend Property (SSHReverseTunnel Component)

A string of data to be sent to the remote host.

Syntax

__property String DataToSend[int SSHChannelId] = { write=FSetDataToSend };
__property DynamicArray<Byte> DataToSendB[int SSHChannelId] = { write=FSetDataToSendB };

Default Value

""

Remarks

A string of data to be sent to the remote host. Write-only property.

Assigning a string to the DataToSend makes the component send the string to the remote host.

Note:It is recommended to use the SendText or SendBytes method instead of setting this property.

The SSHChannelId parameter specifies the index of the item in the array. The size of the array is controlled by the SSHChannelCount property.

This property is write-only and not available at design time.

Data Type

Byte Array

ForwardingHost Property (SSHReverseTunnel Component)

Holds the host to which incoming traffic is forwarded.

Syntax

__property String ForwardingHost[int SSHChannelId] = { read=FForwardingHost };

Default Value

""

Remarks

Holds the host to which incoming traffic is forwarded. This is only applicable if local forwarding was requested when calling RequestForwarding.

The SSHChannelId parameter specifies the index of the item in the array. The size of the array is controlled by the SSHChannelCount property.

This property is read-only and not available at design time.

Data Type

String

ForwardingPort Property (SSHReverseTunnel Component)

Holds the port to which incoming traffic is forwarded.

Syntax

__property int ForwardingPort[int SSHChannelId] = { read=FForwardingPort };

Default Value

0

Remarks

Holds the port to which incoming traffic is forwarded. This is only applicable if local forwarding was requested when calling RequestForwarding.

The SSHChannelId parameter specifies the index of the item in the array. The size of the array is controlled by the SSHChannelCount property.

This property is read-only and not available at design time.

Data Type

Integer

OriginAddress Property (SSHReverseTunnel Component)

This property holds the address of the client which originated the connection to the reverse tunnel on SSHHost .

Syntax

__property String OriginAddress[int SSHChannelId] = { read=FOriginAddress };

Default Value

""

Remarks

This property holds the address of the client which originated the connection to the reverse tunnel on SSHHost.

The SSHChannelId parameter specifies the index of the item in the array. The size of the array is controlled by the SSHChannelCount property.

This property is read-only and not available at design time.

Data Type

String

OriginPort Property (SSHReverseTunnel Component)

This property holds the port used by the client which originated the connection to the reverse tunnel on SSHHost .

Syntax

__property int OriginPort[int SSHChannelId] = { read=FOriginPort };

Default Value

0

Remarks

This property holds the port used by the client which originated the connection to the reverse tunnel on SSHHost.

The SSHChannelId parameter specifies the index of the item in the array. The size of the array is controlled by the SSHChannelCount property.

This property is read-only and not available at design time.

Data Type

Integer

Service Property (SSHReverseTunnel Component)

This property holds the channel type that was requested when opening the channel.

Syntax

__property String Service[int SSHChannelId] = { read=FService };

Default Value

""

Remarks

This property holds the channel type that was requested when opening the channel. For instance "session" or "forwarded-tcpip".

The SSHChannelId parameter specifies the index of the item in the array. The size of the array is controlled by the SSHChannelCount property.

This property is read-only and not available at design time.

Data Type

String

Connected Property (SSHReverseTunnel Component)

This shows whether the component is connected.

Syntax

__property bool Connected = { read=FConnected, write=FSetConnected };

Default Value

False

Remarks

This property is used to determine whether or not the component is connected to the remote host.

Note: It is recommended to use the Connect or Disconnect method instead of setting this property.

This property is not available at design time.

Data Type

Boolean

FirewallAutoDetect Property (SSHReverseTunnel Component)

This property tells the component whether or not to automatically detect and use firewall system settings, if available.

Syntax

__property bool FirewallAutoDetect = { read=FFirewallAutoDetect, write=FSetFirewallAutoDetect };

Default Value

False

Remarks

This property tells the component whether or not to automatically detect and use firewall system settings, if available.

Data Type

Boolean

FirewallType Property (SSHReverseTunnel Component)

This property determines the type of firewall to connect through.

Syntax

__property TiphSSHReverseTunnelFirewallTypes FirewallType = { read=FFirewallType, write=FSetFirewallType };

enum TiphSSHReverseTunnelFirewallTypes {
  fwNone=0,
  fwTunnel=1,
  fwSOCKS4=2,
  fwSOCKS5=3,
  fwSOCKS4A=10
};

Default Value

fwNone

Remarks

This property determines the type of firewall to connect through. The applicable values are as follows:

Data Type

Integer

FirewallHost Property (SSHReverseTunnel Component)

This property contains the name or IP address of firewall (optional).

Syntax

__property String FirewallHost = { read=FFirewallHost, write=FSetFirewallHost };

Default Value

""

Remarks

This property contains the name or IP address of firewall (optional). If a FirewallHost is given, the requested connections will be authenticated through the specified firewall when connecting.

If this property is set to a Domain Name, a DNS request is initiated. Upon successful termination of the request, this property is set to the corresponding address. If the search is not successful, the component raises an exception.

Data Type

String

FirewallPassword Property (SSHReverseTunnel Component)

This property contains a password if authentication is to be used when connecting through the firewall.

Syntax

__property String FirewallPassword = { read=FFirewallPassword, write=FSetFirewallPassword };

Default Value

""

Remarks

This property contains a password if authentication is to be used when connecting through the firewall. If FirewallHost is specified, the FirewallUser and FirewallPassword properties are used to connect and authenticate to the given firewall. If the authentication fails, the component raises an exception.

Data Type

String

FirewallPort Property (SSHReverseTunnel Component)

This property contains the transmission control protocol (TCP) port for the firewall Host .

Syntax

__property int FirewallPort = { read=FFirewallPort, write=FSetFirewallPort };

Default Value

0

Remarks

This property contains the transmission control protocol (TCP) port for the firewall FirewallHost. See the description of the FirewallHost property for details.

Note: This property is set automatically when FirewallType is set to a valid value. See the description of the FirewallType property for details.

Data Type

Integer

FirewallUser Property (SSHReverseTunnel Component)

This property contains a user name if authentication is to be used connecting through a firewall.

Syntax

__property String FirewallUser = { read=FFirewallUser, write=FSetFirewallUser };

Default Value

""

Remarks

This property contains a user name if authentication is to be used connecting through a firewall. If the FirewallHost is specified, this property and FirewallPassword properties are used to connect and authenticate to the given Firewall. If the authentication fails, the component raises an exception.

Data Type

String

LocalHost Property (SSHReverseTunnel Component)

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

Syntax

__property String LocalHost = { read=FLocalHost, write=FSetLocalHost };

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.

Data Type

String

LocalPort Property (SSHReverseTunnel Component)

The TCP port in the local host where the component binds.

Syntax

__property int LocalPort = { read=FLocalPort, write=FSetLocalPort };

Default Value

0

Remarks

This property 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 property to 0 (default) enables the system to choose an open port at random. The chosen port will be returned by the LocalPort property after the connection is established.

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

This property is useful when trying to connect to services that require a trusted port in the client side.

Data Type

Integer

SSHAcceptServerHostKeyEncoded Property (SSHReverseTunnel Component)

This is the certificate (PEM/Base64 encoded).

Syntax

__property String SSHAcceptServerHostKeyEncoded = { read=FSSHAcceptServerHostKeyEncoded, write=FSetSSHAcceptServerHostKeyEncoded };
__property DynamicArray<Byte> SSHAcceptServerHostKeyEncodedB = { read=FSSHAcceptServerHostKeyEncodedB, write=FSetSSHAcceptServerHostKeyEncodedB };

Default Value

""

Remarks

This is the certificate (PEM/Base64 encoded). This property is used to assign a specific certificate. The SSHAcceptServerHostKeyStore and SSHAcceptServerHostKeySubject properties also may be used to specify a certificate.

When SSHAcceptServerHostKeyEncoded is set, a search is initiated in the current SSHAcceptServerHostKeyStore for the private key of the certificate. If the key is found, SSHAcceptServerHostKeySubject is updated to reflect the full subject of the selected certificate; otherwise, SSHAcceptServerHostKeySubject is set to an empty string.

This property is not available at design time.

Data Type

Byte Array

SSHAuthMode Property (SSHReverseTunnel Component)

The authentication method to be used the component when calling SSHLogon .

Syntax

__property TiphSSHReverseTunnelSSHAuthModes SSHAuthMode = { read=FSSHAuthMode, write=FSetSSHAuthMode };

enum TiphSSHReverseTunnelSSHAuthModes {
  amNone=0,
  amMultiFactor=1,
  amPassword=2,
  amPublicKey=3,
  amKeyboardInteractive=4,
  amGSSAPIWithMic=5,
  amCustom=6,
  amGSSAPIKeyex=7
};

Default Value

amPassword

Remarks

The SSH Authentication specification (RFC 4252) specifies multiple methods by which a user can be authenticated by an SSH server. When a call is made to SSHLogon, the component will connect to the SSH server and establish the security layer. After the connection has been secured, the client will send an authentication request to the SSHHost containing the SSHUser. The server will respond containing a list of methods by which that user may be authenticated.

The component will attempt to authenticate the user by one of those methods based on the value of SSHAuthMode and other property values supplied by the user. Currently, the component supports the following authentication methods:

Example (User/Password Auth): Control.SSHAuthMode = SftpSSHAuthModes.amPassword Control.SSHUser = "username" Control.SSHPassword = "password" Control.SSHLogon("server", 22) Example (Public Key Auth): Control.SSHAuthMode = SftpSSHAuthModes.amPublicKey Control.SSHUser = "username" Control.SSHCertStoreType = SSHCertStoreTypes.cstPFXFile; Control.SSHCertStore = "cert.pfx"; Control.SSHCertStorePassword = "certpassword"; Control.SSHCertSubject = "*"; Control.SSHLogon("server", 22)

Data Type

Integer

SSHCertEncoded Property (SSHReverseTunnel Component)

This is the certificate (PEM/Base64 encoded).

Syntax

__property String SSHCertEncoded = { read=FSSHCertEncoded, write=FSetSSHCertEncoded };
__property DynamicArray<Byte> SSHCertEncodedB = { read=FSSHCertEncodedB, write=FSetSSHCertEncodedB };

Default Value

""

Remarks

This is the certificate (PEM/Base64 encoded). This property is used to assign a specific certificate. The SSHCertStore and SSHCertSubject properties also may be used to specify a certificate.

When SSHCertEncoded is set, a search is initiated in the current SSHCertStore for the private key of the certificate. If the key is found, SSHCertSubject is updated to reflect the full subject of the selected certificate; otherwise, SSHCertSubject is set to an empty string.

This property is not available at design time.

Data Type

Byte Array

SSHCertStore Property (SSHReverseTunnel Component)

This is the name of the certificate store for the client certificate.

Syntax

__property String SSHCertStore = { read=FSSHCertStore, write=FSetSSHCertStore };
__property DynamicArray<Byte> SSHCertStoreB = { read=FSSHCertStoreB, write=FSetSSHCertStoreB };

Default Value

"MY"

Remarks

This is the name of the certificate store for the client certificate.

The SSHCertStoreType property denotes the type of the certificate store specified by SSHCertStore. If the store is password protected, specify the password in SSHCertStorePassword.

SSHCertStore is used in conjunction with the SSHCertSubject property to specify client certificates. If SSHCertStore has a value, and SSHCertSubject or SSHCertEncoded is set, a search for a certificate is initiated. Please see the SSHCertSubject property for details.

Designations of certificate stores are platform dependent.

The following designations are the most common User and Machine certificate stores in Windows:

When the certificate store type is PFXFile, this property must be set to the name of the file. When the type is PFXBlob, the property must be set to the binary contents of a PFX file (i.e., PKCS#12 certificate store).

Data Type

Byte Array

SSHCertStorePassword Property (SSHReverseTunnel Component)

If the type of certificate store requires a password, this property is used to specify the password needed to open the certificate store.

Syntax

__property String SSHCertStorePassword = { read=FSSHCertStorePassword, write=FSetSSHCertStorePassword };

Default Value

""

Remarks

If the type of certificate store requires a password, this property is used to specify the password needed to open the certificate store.

Data Type

String

SSHCertStoreType Property (SSHReverseTunnel Component)

This is the type of certificate store for this certificate.

Syntax

__property TiphSSHReverseTunnelSSHCertStoreTypes SSHCertStoreType = { read=FSSHCertStoreType, write=FSetSSHCertStoreType };

enum TiphSSHReverseTunnelSSHCertStoreTypes {
  cstUser=0,
  cstMachine=1,
  cstPFXFile=2,
  cstPFXBlob=3,
  cstJKSFile=4,
  cstJKSBlob=5,
  cstPEMKeyFile=6,
  cstPEMKeyBlob=7,
  cstPublicKeyFile=8,
  cstPublicKeyBlob=9,
  cstSSHPublicKeyBlob=10,
  cstP7BFile=11,
  cstP7BBlob=12,
  cstSSHPublicKeyFile=13,
  cstPPKFile=14,
  cstPPKBlob=15,
  cstXMLFile=16,
  cstXMLBlob=17,
  cstJWKFile=18,
  cstJWKBlob=19,
  cstSecurityKey=20,
  cstBCFKSFile=21,
  cstBCFKSBlob=22,
  cstPKCS11=23,
  cstAuto=99
};

Default Value

cstUser

Remarks

This is the type of certificate store for this certificate.

The component supports both public and private keys in a variety of formats. When the cstAuto value is used, the component will automatically determine the type. This property can take one of the following values:

Data Type

Integer

SSHCertSubject Property (SSHReverseTunnel Component)

This is the subject of the certificate used for client authentication.

Syntax

__property String SSHCertSubject = { read=FSSHCertSubject, write=FSetSSHCertSubject };

Default Value

""

Remarks

This is the subject of the certificate used for client authentication.

This property must be set after all other certificate properties are set. When this property is set, a search is performed in the current certificate store to locate a certificate with a matching subject.

If a matching certificate is found, the property is set to the full subject of the matching certificate.

If an exact match is not found, the store is searched for subjects containing the value of the property.

If a match is still not found, the property is set to an empty string, and no certificate is selected.

The special value "*" picks a random certificate in the certificate store.

The certificate subject is a comma-separated list of distinguished name fields and values. For instance, "CN=www.server.com, OU=test, C=US, E=support@nsoftware.com". Common fields and their meanings are as follows:

If a field value contains a comma, it must be quoted.

Data Type

String

SSHCompressionAlgorithms Property (SSHReverseTunnel Component)

A comma-separated list containing all allowable compression algorithms.

Syntax

__property String SSHCompressionAlgorithms = { read=FSSHCompressionAlgorithms, write=FSetSSHCompressionAlgorithms };

Default Value

"none,zlib"

Remarks

During the SSH handshake, this list will be used to negotiate the compression algorithm to be used between the client and server. This list is used for both directions: client to server and server to client. When negotiating algorithms, each side sends a list of all algorithms it supports or allows. The algorithm chosen for each direction is the first algorithm to appear in the sender's list that the receiver supports, so it is important to list multiple algorithms in preferential order. If no algorithm can be agreed upon, the component will raise an error and the connection will be aborted.

At least one supported algorithm must appear in this list. The following compression algorithms are supported by the component:

• zlib
• zlib@openssh.com
• none

Data Type

String

SSHEncryptionAlgorithms Property (SSHReverseTunnel Component)

A comma-separated list containing all allowable encryption algorithms.

Syntax

__property String SSHEncryptionAlgorithms = { read=FSSHEncryptionAlgorithms, write=FSetSSHEncryptionAlgorithms };

Default Value

"aes256-ctr,aes192-ctr,aes128-ctr,aes256-cbc,aes192-cbc,aes128-cbc,3des-ctr,3des-cbc,blowfish-cbc,arcfour256,arcfour128,arcfour,cast128-cbc,aes256-gcm@openssh.com,aes128-gcm@openssh.com,chacha20-poly1305@openssh.com"

Remarks

During the SSH handshake, this list will be used to negotiate the encryption algorithm to be used between the client and server. This list is used for both directions: client to server and server to client. When negotiating algorithms, each side sends a list of all algorithms it supports or allows. The algorithm chosen for each direction is the first algorithm to appear in the sender's list that the receiver supports, so it is important to list multiple algorithms in preferential order. If no algorithm can be agreed upon, the component will raise an error and the connection will be aborted.

At least one supported algorithm must appear in this list. The following encryption algorithms are supported by the component:

Data Type

String

SSHHost Property (SSHReverseTunnel Component)

The address of the SSH host.

Syntax

__property String SSHHost = { read=FSSHHost, write=FSetSSHHost };

Default Value

""

Remarks

The SSHHost property specifies the IP address (IP number in dotted internet format) or Domain Name of the remote host. It is set before a connection is attempted and cannot be changed once a connection is established.

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

The SSHHost must be the same host that will be assumed for SSH as for the remote service being connected to.

Data Type

String

SSHPassword Property (SSHReverseTunnel Component)

The password for SSH password-based authentication.

Syntax

__property String SSHPassword = { read=FSSHPassword, write=FSetSSHPassword };

Default Value

""

Remarks

SSHPassword specifies the password which is used to authenticate the client to the SSH server.

Data Type

String

SSHPort Property (SSHReverseTunnel Component)

The port on the SSH server where the SSH service is running; by default, 22.

Syntax

__property int SSHPort = { read=FSSHPort, write=FSetSSHPort };

Default Value

22

Remarks

The SSHPort specifies a service port on the SSH host to connect to.

A valid port number (a value between 1 and 65535) is required for the connection to take place. The property must be set before a connection is attempted and cannot be changed once a connection is established. Any attempt to change this property while connected will fail with an error.

Data Type

Integer

SSHUser Property (SSHReverseTunnel Component)

The username for SSH authentication.

Syntax

__property String SSHUser = { read=FSSHUser, write=FSetSSHUser };

Default Value

""

Remarks

SSHUser specifies the username which is used to authenticate the client to the SSH server. This property is required.

Example (User/Password Auth): Control.SSHAuthMode = SftpSSHAuthModes.amPassword Control.SSHUser = "username" Control.SSHPassword = "password" Control.SSHLogon("server", 22) Example (Public Key Auth): Control.SSHAuthMode = SftpSSHAuthModes.amPublicKey Control.SSHUser = "username" Control.SSHCertStoreType = SSHCertStoreTypes.cstPFXFile; Control.SSHCertStore = "cert.pfx"; Control.SSHCertStorePassword = "certpassword"; Control.SSHCertSubject = "*"; Control.SSHLogon("server", 22)

Data Type

String

Timeout Property (SSHReverseTunnel Component)

A timeout for the component.

Syntax

__property int Timeout = { read=FTimeout, write=FSetTimeout };

Default Value

60

Remarks

If the Timeout property is set to 0, all operations return immediately, potentially failing with a WOULDBLOCK error if data cannot be sent immediately.

If Timeout is set to a positive value, data is sent in a blocking manner and the component will wait for the operation to complete before returning control. The component will handle any potential WOULDBLOCK errors internally and automatically retry the operation for a maximum of Timeout seconds.

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 raises 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.

Data Type

Integer

CancelForwarding Method (SSHReverseTunnel Component)

Requests the server to stop forwarding a remote TCP/IP port.

Syntax

void __fastcall CancelForwarding(String Address, int Port);

Remarks

The CancelForwarding cancels a previous TCP/IP port forwarding request. When calling it, provide the same argument values you provided on the RequestForwarding call.

CloseChannel Method (SSHReverseTunnel Component)

Closes a existing SSHChannel .

Syntax

void __fastcall CloseChannel(String ChannelId);

Remarks

ChannelId is the identifier for the SSH channel to be closed.

Config Method (SSHReverseTunnel Component)

Sets or retrieves a configuration setting.

Syntax

String __fastcall Config(String ConfigurationString);

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.

DecodePacket Method (SSHReverseTunnel Component)

Decodes a hex-encoded SSH packet.

Syntax

DynamicArray<Byte> __fastcall DecodePacket(String EncodedPacket);

Remarks

This method is used to decode an SSH packet created by EncodePacket.

Note: This method is only applicable for reading and creating SSH packets for use within the SSHCustomAuth event.

DoEvents Method (SSHReverseTunnel Component)

Processes events from the internal message queue.

Syntax

void __fastcall DoEvents();

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.

EncodePacket Method (SSHReverseTunnel Component)

Hex encodes an SSH packet.

Syntax

String __fastcall EncodePacket(DynamicArray<Byte> Packet);

Remarks

This method is used to encode a raw SSH packet created by SetSSHParam.

Note: This method is only applicable for reading and creating SSH packets for use within the SSHCustomAuth event.

ExchangeKeys Method (SSHReverseTunnel Component)

Causes the component to exchange a new set of session keys with the SSHHost .

Syntax

void __fastcall ExchangeKeys();

Remarks

SSH key renegotiation can be initiated by either end of an established SSH connection. ExchangeKeys allows the user to start such a renegotiation with the SSHHost. During this process, SSHStatus events will fire containing updates regarding the key negotiation process.

The SSH 2.0 specification recommends that key renegotiation be done once for 2 gigabytes (GB) of data processed by the connection, or once every day. This makes it more difficult to break the security of data-intensive or long-lived connections.

GetSSHParam Method (SSHReverseTunnel Component)

Used to read a field from an SSH packet's payload.

Syntax

String __fastcall GetSSHParam(DynamicArray<Byte> Payload, String Field);

Remarks

This method is used to read the value of a particular field from an SSH packet's payload. Payload should contain the full payload of a packet received by an event such as SSHChannelRequest. Field is the name of a field to be read out of the packet.

The following is a list of the names of well-known channel request field names and their encodings:

The remaining fields that are available in the payload are dependent upon the value of RequestType.

pty-req

Pty-req is a request to open a pseudo terminal on the specified channel. The following fields are available:

x11-req

X11-req is a request to forward x11 sessions over a channel. The following fields are available:

env

Env is a request to set an environment variable to be passed into a shell that may be started later. The following fields are available:

exec

Exec is a request to execute a command on the channel using the authenticated user's shell. The following field is available:

subsystem

Subsystem is a request to start a subsystem on the specified channel. The following field is available:

xon-xoff

Instructs the server to allow or disallow control-S/control-Q style flow control. The following field is available:

signal

Sends a signal to the remote process/service. The following field is available:

If the packet type is not well known, Field should start with the special character "%" and contain a comma-separated list of field types as defined in SetSSHParam. For example, reading out the X11AuthProtocol of an x11-req payload, you can use "%s,f".

Note: the return value is a string encoded the same way as the FieldValue param in SetSSHParam.

Note: This method is only applicable for reading and creating SSH packets for use within the SSHCustomAuth event.

GetSSHParamBytes Method (SSHReverseTunnel Component)

Used to read a field from an SSH packet's payload.

Syntax

DynamicArray<Byte> __fastcall GetSSHParamBytes(DynamicArray<Byte> Payload, String Field);

Remarks

This method is the same as calling GetSSHParam, but returns raw bytes instead of strings.

Note: This method is only applicable for reading and creating SSH packets for use within the SSHCustomAuth event.

RequestForwarding Method (SSHReverseTunnel Component)

Requests the server to forward a remote TCP/IP port.

Syntax

void __fastcall RequestForwarding(String Address, int Port, String ForwardingHost, int ForwardingPort);

Remarks

The RequestForwarding method asks the server to listen at the specified TCP/IP Address and Port for connection requests and then forward them as new SSH channels to the component.

ForwardingHost and ForwardingPort may be used to specify an address and port to which traffic will automatically be forwarded. If automatic forwarding is not desired, specify an empty string ("") for the ForwardingHost parameter.

The Address argument can be specified in different ways:

• "" means that connections are to be accepted on all protocol families supported by the server.
• "0.0.0.0" means to listen on all IPv4 addresses.
• "::" means to listen on all IPv6 addresses.
• "localhost" means to listen on all protocol families supported by the SSH implementation on loopback addresses only.
• "127.0.0.1" and "::1" indicate listening on the loopback interfaces for IPv4 and IPv6, respectively.

Passing a value of 0 for the Port parameter instructs the server to assign a port. In this case, query the ForwardedPort setting to determine the port that was assigned by the server.

The component has two modes that allow data to be dealt with directly from the events, or automatically forwarded on to a different endpoint.

Event Based Operation

In this mode, any data received by the component over the tunnel causes the events of the component to fire. For instance:

SSHReverseTunnel.RequestForwarding("0.0.0.0", 777, "", 0);

In the above code, forwarding is requested from port 777 on the SSHHost. Any data received on port 777 by the SSHHost will be sent to the component. In the above code, the last two parameters are empty and 0, indicating to the component that no local forwarding is requested.

Once RequestForwarding returns, the SSH reverse tunnel is established. Any connection made to the SSH host on the specified port will then trigger the component's events to fire, allowing you to handle the connection request and data.

When a client connects to the SSH host on the specified port, the SSHChannelOpenRequest event will fire. Within this event, choose to accept or reject the connection by setting the Accept parameter. This event contains details about the connection that may be used when determining whether to accept the connection.

After the channel is established, data is received through the SSHChannelData event. Call the SendChannelData method to send data over the channel, and call the CloseChannel method to close the channel.

Local Forwarding

In this mode, any data received by the component is automatically forwarded to a separate endpoint. This allows the component to act as a sort of proxy. There is no need to handle data directly in this case. For instance: SSHReverseTunnel.RequestForwarding("0.0.0.0", 777, "nsoftware.com", 80);

In the above code, forwarding is requested from port 777 on SSHHost. The component is instructed to establish a connection to "nsoftware.com" on port 80 when a client connects to SSHHost on port 777. Any data received from the client connected to SSHHost on port 777 will automatically be forwarded to "nsoftware.com" on port 80. Any data received back from "nsoftware.com" on port 80 will be sent back to the connected client.

In this mode, data may flow freely from the client connected to the SSHHost to the endpoint specified in the RequestForwarding method without any additional code required.

Reset Method (SSHReverseTunnel Component)

Reset the component.

Syntax

void __fastcall Reset();

Remarks

This method will reset the component's properties to their default values.

SendChannelData Method (SSHReverseTunnel Component)

Used to send data over an SSH channel.

Syntax

void __fastcall SendChannelData(String ChannelId, DynamicArray<Byte> Data);

Remarks

This method can be used to send arbitrary data to the channel with the specified ChannelId.

SetSSHParam Method (SSHReverseTunnel Component)

Used to write a field to the end of a payload.

Syntax

DynamicArray<Byte> __fastcall SetSSHParam(DynamicArray<Byte> Payload, String FieldType, String FieldValue);

Remarks

This method is used to build the payload portion of an SSH packet to be sent later by a call to SendSSHPacket. Payload should contain the result of a previous call to SetSSHParam. FieldType is a string defining the type of field to be written to the packet. FieldValue should be the string representation of the field to be written.

The following is a list of supported field types and a description of how FieldValue should be encoded:

Note: integer values may be encoded in hexadecimal by prefixing "0x" to the beginning of the string, otherwise the value is assumed to be base-10.

Note: This method is only applicable for reading and creating SSH packets for use within the SSHCustomAuth event.

SSHLogoff Method (SSHReverseTunnel Component)

Logoff from the SSH server.

Syntax

void __fastcall SSHLogoff();

Remarks

Logoff from the SSH server. If that fails, the connection is terminated by the local host.

SSHLogon Method (SSHReverseTunnel Component)

Logon to the SSHHost using the current SSHUser and SSHPassword .

Syntax

void __fastcall SSHLogon(String SSHHost, int SSHPort);

Remarks

Logon to the SSH server using the current SSHUser and SSHPassword. This will perform the SSH handshake and authentication.

Example (Logging On)

SSHClient.SSHUser = "username" SSHClient.SSHPassword = "password" SSHClient.SSHLogon("sshHost", sshPort)

Connected Event (SSHReverseTunnel Component)

This event is fired immediately after a connection completes (or fails).

Syntax

typedef struct {
  int StatusCode;
  String Description;
} TiphSSHReverseTunnelConnectedEventParams;
typedef void __fastcall (__closure *TiphSSHReverseTunnelConnectedEvent)(System::TObject* Sender, TiphSSHReverseTunnelConnectedEventParams *e);
__property TiphSSHReverseTunnelConnectedEvent OnConnected = { read=FOnConnected, write=FOnConnected };

Remarks

If the connection is made normally, StatusCode is 0 and Description is "OK".

If the connection fails, StatusCode has the error code returned by the Transmission Control Protocol (TCP)/IP stack. Description contains a description of this code. The value of StatusCode is equal to the value of the error.

Please refer to the Error Codes section for more information.

ConnectionStatus Event (SSHReverseTunnel Component)

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

Syntax

typedef struct {
  String ConnectionEvent;
  int StatusCode;
  String Description;
} TiphSSHReverseTunnelConnectionStatusEventParams;
typedef void __fastcall (__closure *TiphSSHReverseTunnelConnectionStatusEvent)(System::TObject* Sender, TiphSSHReverseTunnelConnectionStatusEventParams *e);
__property TiphSSHReverseTunnelConnectionStatusEvent OnConnectionStatus = { read=FOnConnectionStatus, write=FOnConnectionStatus };

Remarks

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

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

Disconnected Event (SSHReverseTunnel Component)

This event is fired when a connection is closed.

Syntax

typedef struct {
  int StatusCode;
  String Description;
} TiphSSHReverseTunnelDisconnectedEventParams;
typedef void __fastcall (__closure *TiphSSHReverseTunnelDisconnectedEvent)(System::TObject* Sender, TiphSSHReverseTunnelDisconnectedEventParams *e);
__property TiphSSHReverseTunnelDisconnectedEvent OnDisconnected = { read=FOnDisconnected, write=FOnDisconnected };

Remarks

If the connection is broken normally, StatusCode is 0 and Description is "OK".

If the connection is broken for any other reason, StatusCode has the error code returned by the Transmission Control Protocol (TCP/IP) subsystem. Description contains a description of this code. The value of StatusCode is equal to the value of the TCP/IP error.

Please refer to the Error Codes section for more information.

Error Event (SSHReverseTunnel Component)

Fired when information is available about errors during data delivery.

Syntax

typedef struct {
  int ErrorCode;
  String Description;
} TiphSSHReverseTunnelErrorEventParams;
typedef void __fastcall (__closure *TiphSSHReverseTunnelErrorEvent)(System::TObject* Sender, TiphSSHReverseTunnelErrorEventParams *e);
__property TiphSSHReverseTunnelErrorEvent OnError = { read=FOnError, write=FOnError };

Remarks

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

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

Log Event (SSHReverseTunnel Component)

Fires once for each log message.

Syntax

typedef struct {
  int LogLevel;
  String Message;
  String LogType;
} TiphSSHReverseTunnelLogEventParams;
typedef void __fastcall (__closure *TiphSSHReverseTunnelLogEvent)(System::TObject* Sender, TiphSSHReverseTunnelLogEventParams *e);
__property TiphSSHReverseTunnelLogEvent OnLog = { read=FOnLog, write=FOnLog };

Remarks

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

LogLevel indicates the detail level of the message. Possible values are:

Message is the log message.

LogType is reserved for future use.

ReconnectAttempt Event (SSHReverseTunnel Component)

Fires when attempting to reconnect.

Syntax

typedef struct {
  String Host;
  int Port;
  int RetryCount;
  int RetriesRemaining;
  int MaxRetryCount;
  int RetryInterval;
  int RetryType;
  int RemoteListeningPort;
  bool Cancel;
} TiphSSHReverseTunnelReconnectAttemptEventParams;
typedef void __fastcall (__closure *TiphSSHReverseTunnelReconnectAttemptEvent)(System::TObject* Sender, TiphSSHReverseTunnelReconnectAttemptEventParams *e);
__property TiphSSHReverseTunnelReconnectAttemptEvent OnReconnectAttempt = { read=FOnReconnectAttempt, write=FOnReconnectAttempt };

Remarks

This event fires both when attempting to reconnect to the SSHHost and when re-establishing a SSH tunnel.

Only applicable when AutoReconnect is enabled. To determine which type of connection is being established check the RetryType parameter.

The following table provides details about the parameters.

SSHChannelClosed Event (SSHReverseTunnel Component)

Fired when a channel is closed.

Syntax

typedef struct {
  String ChannelId;
} TiphSSHReverseTunnelSSHChannelClosedEventParams;
typedef void __fastcall (__closure *TiphSSHReverseTunnelSSHChannelClosedEvent)(System::TObject* Sender, TiphSSHReverseTunnelSSHChannelClosedEventParams *e);
__property TiphSSHReverseTunnelSSHChannelClosedEvent OnSSHChannelClosed = { read=FOnSSHChannelClosed, write=FOnSSHChannelClosed };

Remarks

The SSHChannelClosed event is fired when a channel is closed on an SSH connection.

Note: Processing long-running requests, including sending channel data, inside this event may cause the underlying transport to stop processing SSH data until the event returns. In order to prevent this from happening, all requests should be processed asynchronously in a separate thread outside of this event.

SSHChannelData Event (SSHReverseTunnel Component)

Fired when the SSHHost sends channel data to the client.

Syntax

typedef struct {
  String ChannelId;
  String ChannelData;
  DynamicArray<Byte> ChannelDataB;
} TiphSSHReverseTunnelSSHChannelDataEventParams;
typedef void __fastcall (__closure *TiphSSHReverseTunnelSSHChannelDataEvent)(System::TObject* Sender, TiphSSHReverseTunnelSSHChannelDataEventParams *e);
__property TiphSSHReverseTunnelSSHChannelDataEvent OnSSHChannelData = { read=FOnSSHChannelData, write=FOnSSHChannelData };

Remarks

The SSHChannelData event will fire as data is received for the given ChannelId. ChannelData will contain the decrypted contents of the SSH packet.

SSHChannelEOF Event (SSHReverseTunnel Component)

Fired when the remote peer signals the end of the data stream for the channel.

Syntax

typedef struct {
  String ChannelId;
} TiphSSHReverseTunnelSSHChannelEOFEventParams;
typedef void __fastcall (__closure *TiphSSHReverseTunnelSSHChannelEOFEvent)(System::TObject* Sender, TiphSSHReverseTunnelSSHChannelEOFEventParams *e);
__property TiphSSHReverseTunnelSSHChannelEOFEvent OnSSHChannelEOF = { read=FOnSSHChannelEOF, write=FOnSSHChannelEOF };

Remarks

The SSHChannelEOF event is fired when the end of the data stream for a channel on an SSH connection is reached.

Note: Processing long-running requests, including sending channel data, inside this event may cause the underlying transport to stop processing SSH data until the event returns. In order to prevent this from happening, all requests should be processed asynchronously in a separate thread outside of this event.

SSHChannelOpened Event (SSHReverseTunnel Component)

Fired when a channel is successfully opened.

Syntax

typedef struct {
  String ChannelId;
} TiphSSHReverseTunnelSSHChannelOpenedEventParams;
typedef void __fastcall (__closure *TiphSSHReverseTunnelSSHChannelOpenedEvent)(System::TObject* Sender, TiphSSHReverseTunnelSSHChannelOpenedEventParams *e);
__property TiphSSHReverseTunnelSSHChannelOpenedEvent OnSSHChannelOpened = { read=FOnSSHChannelOpened, write=FOnSSHChannelOpened };

Remarks

The SSHChannelOpened event is fired when a channel is successfully opened on an SSH connection.

Note: Processing long-running requests, including sending channel data, inside this event may cause the underlying transport to stop processing SSH data until the event returns. In order to prevent this from happening, all requests should be processed asynchronously in a separate thread outside of this event.

SSHChannelOpenRequest Event (SSHReverseTunnel Component)

Fired when the peer attempts to open a new channel.

Syntax

typedef struct {
  String ChannelId;
  String Service;
  String ConnectedAddress;
  int ConnectedPort;
  String OriginAddress;
  int OriginPort;
  bool Accept;
} TiphSSHReverseTunnelSSHChannelOpenRequestEventParams;
typedef void __fastcall (__closure *TiphSSHReverseTunnelSSHChannelOpenRequestEvent)(System::TObject* Sender, TiphSSHReverseTunnelSSHChannelOpenRequestEventParams *e);
__property TiphSSHReverseTunnelSSHChannelOpenRequestEvent OnSSHChannelOpenRequest = { read=FOnSSHChannelOpenRequest, write=FOnSSHChannelOpenRequest };

Remarks

This event is fired whenever a peer attempts to open a new channel for a given connection. ChannelId will contain the id of the channel to be created. Service will identify the type of channel that is being requested. Usually, this will be "forwarded-tcpip", in which case ConnectedAddress and ConnectedPort will contain the remote TCP/IP address and port on the peer to which the connection was established; OriginAddress and OriginPort contain the originating TCP/IP address and port of the connection.

By default Accept is True and the channel will be opened. Set Accept to False to reject the request.

SSHChannelReadyToSend Event (SSHReverseTunnel Component)

Fired when the component is ready to send data.

Syntax

typedef struct {
  String ChannelId;
} TiphSSHReverseTunnelSSHChannelReadyToSendEventParams;
typedef void __fastcall (__closure *TiphSSHReverseTunnelSSHChannelReadyToSendEvent)(System::TObject* Sender, TiphSSHReverseTunnelSSHChannelReadyToSendEventParams *e);
__property TiphSSHReverseTunnelSSHChannelReadyToSendEvent OnSSHChannelReadyToSend = { read=FOnSSHChannelReadyToSend, write=FOnSSHChannelReadyToSend };

Remarks

This event fires when data can be sent over the SSH Channel specified by ChannelId.

When a channel is opened this event will fire once the channel is ready and data can be sent.

When Timeout is set to 0 (asynchronous) sending data may result in an error if the channel or underlying socket cannot accept more data to send. Monitor SSHChannelReadyToSend or ReadyToSend to determine when data can be sent again.

When Timeout is set to a positive value the component will block when sending data until the data can be successfully sent and SSHChannelReadyToSend and ReadyToSend do not need to be monitored.

SSHChannelRequest Event (SSHReverseTunnel Component)

Fired when the SSHHost sends a channel request to the client.

Syntax

typedef struct {
  String ChannelId;
  String RequestType;
  String Packet;
  DynamicArray<Byte> PacketB;
  bool Success;
} TiphSSHReverseTunnelSSHChannelRequestEventParams;
typedef void __fastcall (__closure *TiphSSHReverseTunnelSSHChannelRequestEvent)(System::TObject* Sender, TiphSSHReverseTunnelSSHChannelRequestEventParams *e);
__property TiphSSHReverseTunnelSSHChannelRequestEvent OnSSHChannelRequest = { read=FOnSSHChannelRequest, write=FOnSSHChannelRequest };

Remarks

The SSHHost may send requests that affect the status of a particular SSHChannel. Some requests will be automatically handled by the component. However, others may need the attention of the user to be dealt with properly within the scope of the application.

ChannelId identifies the channel receiving the request.

Type will contain the type of the request. These types are dependent upon the type of the channel. For example, a "session" channel executing a command on the remote shell may receive an "exit-status" request containing the return code of that command.

RequestData contains the remainder of the original SSH packet. If the request type has specific parameters, they can be parsed out of this data.

Success should be used to instruct the component to respond to the request with either a success or failure notification. If the request is successful, SSHChannelRequested will fire with the same information in case the request requires further processing.

Note: Processing long-running requests, including sending channel data, inside this event may cause the underlying transport to stop processing SSH data until the event returns. In order to prevent this from happening, all requests should be processed asynchronously in a separate thread outside of this event.

SSHChannelRequested Event (SSHReverseTunnel Component)

Fired if the SSHChannelRequest was successful, any further processing for the channel request should be done here.

Syntax

typedef struct {
  String ChannelId;
  String RequestType;
  String Packet;
  DynamicArray<Byte> PacketB;
} TiphSSHReverseTunnelSSHChannelRequestedEventParams;
typedef void __fastcall (__closure *TiphSSHReverseTunnelSSHChannelRequestedEvent)(System::TObject* Sender, TiphSSHReverseTunnelSSHChannelRequestedEventParams *e);
__property TiphSSHReverseTunnelSSHChannelRequestedEvent OnSSHChannelRequested = { read=FOnSSHChannelRequested, write=FOnSSHChannelRequested };

Remarks

The SSHHost may send requests that affect the status of a particular SSHChannel. Some requests will be automatically handled by the component. However, others may need the attention of the user to be dealt with properly within the scope of the application.

ChannelId identifies the channel receiving the request.

Type will contain the type of the request. These types are dependent upon the type of the channel. For example, a "session" channel executing a command on the remote shell may receive an "exit-status" request containing the return code of that command.

RequestData contains the remainder of the original SSH packet. If the request type has specific parameters, they can be parsed out of this data.

Note: Processing long-running requests, including sending channel data, inside this event may cause the underlying transport to stop processing SSH data until the event returns. In order to prevent this from happening, all requests should be processed asynchronously in a separate thread outside of this event.

SSHCustomAuth Event (SSHReverseTunnel Component)

Fired when the component is doing custom authentication.

Syntax

typedef struct {
  String Packet;
} TiphSSHReverseTunnelSSHCustomAuthEventParams;
typedef void __fastcall (__closure *TiphSSHReverseTunnelSSHCustomAuthEvent)(System::TObject* Sender, TiphSSHReverseTunnelSSHCustomAuthEventParams *e);
__property TiphSSHReverseTunnelSSHCustomAuthEvent OnSSHCustomAuth = { read=FOnSSHCustomAuth, write=FOnSSHCustomAuth };

Remarks

SSHCustomAuth is fired during the user authentication stage of the SSH logon process if SSHAuthMode is set to amCustom. Packet contains the raw last SSH packet sent by the server, in HEX-encoded format.

The client should create a new raw SSH packet to send to the server and set Packet to the HEX-encoded representation of the packet to send.

In all cases, Packet will start with the message type field.

To read the incoming packet call DecodePacket and then use the GetSSHParam and GetSSHParamBytes methods. To create a packet use the SetSSHParam method and then call EncodePacket to obtain a HEX-encoded value and assign this to the Packet parameter.

SSHKeyboardInteractive Event (SSHReverseTunnel Component)

Fired when the component receives a request for user input from the server.

Syntax

typedef struct {
  String Name;
  String Instructions;
  String Prompt;
  String Response;
  bool EchoResponse;
} TiphSSHReverseTunnelSSHKeyboardInteractiveEventParams;
typedef void __fastcall (__closure *TiphSSHReverseTunnelSSHKeyboardInteractiveEvent)(System::TObject* Sender, TiphSSHReverseTunnelSSHKeyboardInteractiveEventParams *e);
__property TiphSSHReverseTunnelSSHKeyboardInteractiveEvent OnSSHKeyboardInteractive = { read=FOnSSHKeyboardInteractive, write=FOnSSHKeyboardInteractive };

Remarks

SSHKeyboardInteractive is fired during the user authentication stage of the SSH logon process. During authentication, the component will request a list of available authentication methods for the SSHUser. For example, if the SSHHost responds with "keyboard-interactive", the component will fire this event to allow the client application to set the password.

During authentication, the SSH server may respond with a request for the user's authentication information. Name is a server-provided value associated with the authentication method such as "CRYPTOCard Authentication". Instructions will contain specific instructions, also supplied by the server, for how the user should respond.

Along with these values, the server will also send at least one input Prompt to be displayed to and filled out by the user. Response should be set to the user's input, and will be sent back in the user authentication information response. EchoResponse is a server recommendation for whether or not the user's response should be echoed back during input.

Note: the server may send several prompts in a single packet. The component will fire the SSHKeyboardInteractive event once for each prompt.

SSHServerAuthentication Event (SSHReverseTunnel Component)

Fired after the server presents its public key to the client.

Syntax

typedef struct {
  String HostKey;
  DynamicArray<Byte> HostKeyB;
  String Fingerprint;
  String KeyAlgorithm;
  String CertSubject;
  String CertIssuer;
  String Status;
  bool Accept;
} TiphSSHReverseTunnelSSHServerAuthenticationEventParams;
typedef void __fastcall (__closure *TiphSSHReverseTunnelSSHServerAuthenticationEvent)(System::TObject* Sender, TiphSSHReverseTunnelSSHServerAuthenticationEventParams *e);
__property TiphSSHReverseTunnelSSHServerAuthenticationEvent OnSSHServerAuthentication = { read=FOnSSHServerAuthentication, write=FOnSSHServerAuthentication };

Remarks

This event is where the client can decide whether to continue with the connection process or not. If the public key is known to be a valid key for the SSH server, Accept should be set to True within the event. Otherwise, the server will not be authenticated and the connection will be broken.

Accept will be True only if either HostKey or Fingerprint is identical to the value of SSHAcceptServerHostKey.

Accept may be set to True manually to accept the server host key.

Note that SSH's security inherently relies on client verification of the host key. Ignoring the host key and always setting Accept to true is strongly discouraged, and could cause potentially serious security vulnerabilities in your application. It is recommended that clients maintain a list of known keys for each server and check HostKey against this list each time a connection is attempted.

Host Key contains the full binary text of the key, in the same format used internally by SSH.

Fingerprint holds the SHA-256 hash of HostKey in the hex-encoded form: 0a:1b:2c:3d. To configure the hash algorithm used to calculate this value see SSHFingerprintHashAlgorithm.

KeyAlgorithm identifies the host key algorithm. Supported values are:

• ssh-rsa
• ssh-dss
• rsa-sha2-256
• rsa-sha2-512
• x509v3-sign-rsa
• x509v3-sign-dss
• ecdsa-sha2-nistp256
• ecdsa-sha2-nistp384
• ecdsa-sha2-nistp521

CertSubject is the subject of the certificate. This is only applicable when KeyAlgorithm is "x509v3-sign-rsa" or "x509v3-sign-dss".

CertIssuer is the issuer of the certificate. This is only applicable when KeyAlgorithm is "x509v3-sign-rsa" or "x509v3-sign-dss".

Status is reserved for future use.

SSHStatus Event (SSHReverseTunnel Component)

Shows the progress of the secure connection.

Syntax

typedef struct {
  String Message;
} TiphSSHReverseTunnelSSHStatusEventParams;
typedef void __fastcall (__closure *TiphSSHReverseTunnelSSHStatusEvent)(System::TObject* Sender, TiphSSHReverseTunnelSSHStatusEventParams *e);
__property TiphSSHReverseTunnelSSHStatusEvent OnSSHStatus = { read=FOnSSHStatus, write=FOnSSHStatus };

Remarks

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

Config Settings (SSHReverseTunnel Component)

SSHReverseTunnel Config Settings

SSHClient Config Settings

*SSH-1.99-*,*SSH-2.0-*,*SSH-2.99-*

TCPClient Config Settings

Socket Config Settings

Base Config Settings

Trappable Errors (SSHReverseTunnel Component)

SSHReverseTunnel Errors

SSHClient Errors

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

TCPClient Errors

TCP/IP Errors