B4X

Multiple Hop SSH to SFTP

See more SFTP Examples

Demonstrates how to SFTP through an intermediate SSH server (multiple hop). The scheme looks like this:

Application => ServerSSH1 => ServerSFtp

The ConnectThroughSsh method is added in Chilkat version 9.5.0.55 to accomplish this task.

B4X

Dim success As Boolean = False

'  This example assumes the Chilkat API to have been previously unlocked.
'  See Global Unlock Sample for sample code.

Dim ssh1 As ChilkatSsh
ssh1.Initialize("ssh1")

'  Hostname may be an IP address or domain name:
Dim hostname As String = "192.168.1.111"
Dim port As String = 22

'  Connect directly to the 1st SSH server:
success = ssh1.Connect(hostname, port)
If success <> True Then
    Log(ssh1.LastErrorText)
    Return
End If


'  Authenticate using login/password:
success = ssh1.AuthenticatePw("myLogin", "myPassword")
If success <> True Then
    Log(ssh1.LastErrorText)
    Return
End If


'  Connect through the 1st SSH connection to reach a 2nd SSH server (for SFTP)
'  Note: Any number of connections may be simultaneously tunneled through a single
'  existing SSH connection.
Dim sftp As ChilkatSFtp
sftp.Initialize("sftp")

'  Connect to some SSH/SFTP server through ssh1.
success = sftp.ConnectThroughSsh(ssh1, "sftp.someremoteserver.com", 22)
If success <> True Then
    Log(sftp.LastErrorText)
    Return
End If


'  Authenticate with the SFTP server. 
success = sftp.AuthenticatePw("myLogin", "myPassword")
If success <> True Then
    Log(sftp.LastErrorText)
    Return
End If


'  After authenticating, the SFTP subsystem must be initialized:
success = sftp.InitializeSftp
If success <> True Then
    Log(sftp.LastErrorText)
    Return
End If


'  Upload from the local file to the SSH server.
'  Important -- the remote filepath is the 1st argument,
'  the local filepath is the 2nd argument;
Dim remoteFilePath As String = "hamlet.xml"
Dim localFilePath As String = "c:/temp/hamlet.xml"

success = sftp.UploadFileByName(remoteFilePath, localFilePath)
If success <> True Then
    Log(sftp.LastErrorText)
    Return
End If


Log("Success.")

'  Close the connection with the SFTP server.(This closes the the tunnel through ssh1.)
'  The connection with ssh1 is still alive, and may be used for more connections.
sftp.Disconnect

'  ...
'  ...
'  ...

ssh1.Disconnect