(SQL Server) SSH -- Running Commands that Prompt for Additional Input, such as "su"

Demonstrates how to run a shell command via SSH where the shell command prompts for additional input from the client. This example demonstrates "su".

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

// Important: See this note about string length limitations for strings returned by sp_OAMethod calls.
//
CREATE PROCEDURE ChilkatSample
AS
BEGIN
    DECLARE @hr int
    DECLARE @sTmp0 nvarchar(4000)
    -- This example assumes the Chilkat API to have been previously unlocked.
    -- See Global Unlock Sample for sample code.

    DECLARE @ssh int
    EXEC @hr = sp_OACreate 'Chilkat_9_5_0.Ssh', @ssh OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    -- Hostname may be an IP address or hostname:
    DECLARE @hostname nvarchar(4000)
    SELECT @hostname = '172.16.16.46'
    DECLARE @port int
    SELECT @port = 22

    DECLARE @success int
    EXEC sp_OAMethod @ssh, 'Connect', @success OUT, @hostname, @port
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    -- If receiving output from a command stalls for more than 5 seconds, then stop waiting.
    EXEC sp_OASetProperty @ssh, 'IdleTimeoutMs', 5000

    EXEC sp_OAMethod @ssh, 'AuthenticatePw', @success OUT, 'myLogin', 'myPassword'
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    -- Open a session channel. 
    DECLARE @channelNum int
    EXEC sp_OAMethod @ssh, 'OpenSessionChannel', @channelNum OUT
    IF @channelNum < 0
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    -- Request a pseudo-terminal
    DECLARE @termType nvarchar(4000)
    SELECT @termType = 'dumb'
    DECLARE @widthInChars int
    SELECT @widthInChars = 120
    DECLARE @heightInChars int
    SELECT @heightInChars = 40
    DECLARE @pixWidth int
    SELECT @pixWidth = 0
    DECLARE @pixHeight int
    SELECT @pixHeight = 0
    EXEC sp_OAMethod @ssh, 'SendReqPty', @success OUT, @channelNum, @termType, @widthInChars, @heightInChars, @pixWidth, @pixHeight
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    -- Start a shell on the channel:
    EXEC sp_OAMethod @ssh, 'SendReqShell', @success OUT, @channelNum
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    -- Send the su command.
    -- (The SSH server I'm using for testing is a Linux Ubuntu
    -- system running OpenSSH.  It is important in this case to send a bare-LF
    -- and not a CRLF.)
    DECLARE @cmd nvarchar(4000)
    SELECT @cmd = 'su' + CHAR(10)
    EXEC sp_OAMethod @ssh, 'ChannelSendString', @success OUT, @channelNum, @cmd, 'ansi'
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    -- Read until we get the prompt for the password:
    EXEC sp_OAMethod @ssh, 'ChannelReceiveUntilMatch', @success OUT, @channelNum, 'Password:', 'ansi', 1
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    -- Display what we've received so far:
    EXEC sp_OAMethod @ssh, 'GetReceivedText', @sTmp0 OUT, @channelNum, 'ansi'
    PRINT @sTmp0

    -- Send the password. (This is the equivalent of typing at the shell prompt.)
    -- Again, make sure it uses a bare-LF and not a CRLF.
    DECLARE @password nvarchar(4000)

    SELECT @password = 'myPassword' + CHAR(10)
    EXEC sp_OAMethod @ssh, 'ChannelSendString', @success OUT, @channelNum, @password, 'ansi'
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    -- Read the response until we get the shell prompt (assuming it's successful)
    -- In my case, the shell prompt is: "chilkat@vivoMini64:~$ "
    DECLARE @myShellPrompt nvarchar(4000)
    SELECT @myShellPrompt = 'chilkat@vivoMini64:~$'
    -- It will be different in your case.
    EXEC sp_OAMethod @ssh, 'ChannelReceiveUntilMatch', @success OUT, @channelNum, @myShellPrompt, 'ansi', 1
    IF @success <> 1
      BEGIN
        -- Check the last-error information and the session log...
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        -- Check to see what was received.  
        EXEC sp_OAMethod @ssh, 'GetReceivedText', @sTmp0 OUT, @channelNum, 'ansi'
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    -- Display what we've received so far.  This clears
    -- the internal receive buffer, which is important. 
    -- After we send the command, we'll be reading until
    -- the next command prompt.  If the command prompt
    -- is already in the internal receive buffer, we'll think we're
    -- already finished...
    EXEC sp_OAMethod @ssh, 'GetReceivedText', @sTmp0 OUT, @channelNum, 'ansi'
    PRINT @sTmp0

    -- Send a command.  In this case, we are sending the "ls" command:
    SELECT @cmd = 'ls' + CHAR(10)
    EXEC sp_OAMethod @ssh, 'ChannelSendString', @success OUT, @channelNum, @cmd, 'ansi'
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    -- Read until the next command prompt:
    EXEC sp_OAMethod @ssh, 'ChannelReceiveUntilMatch', @success OUT, @channelNum, @myShellPrompt, 'ansi', 1
    IF @success <> 1
      BEGIN
        -- Check the last-error information and the session log...
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        -- Check to see what was received.  
        EXEC sp_OAMethod @ssh, 'GetReceivedText', @sTmp0 OUT, @channelNum, 'ansi'
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    -- Display the command output:
    EXEC sp_OAMethod @ssh, 'GetReceivedText', @sTmp0 OUT, @channelNum, 'ansi'
    PRINT @sTmp0

    -- You may continue sending additional commands.
    -- The technique is: send the command, read until the next command prompt,
    -- and then fetch/clear the internal receive buffer.

    -- We're done, so shut it down..

    -- Send an EOF.  This tells the server that no more data will 
    -- be sent on this channel.  The channel remains open, and
    -- the SSH client may still receive output on this channel.
    EXEC sp_OAMethod @ssh, 'ChannelSendEof', @success OUT, @channelNum
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    -- Close the channel:
    EXEC sp_OAMethod @ssh, 'ChannelSendClose', @success OUT, @channelNum
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @ssh, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @ssh
        RETURN
      END

    -- Disconnect
    EXEC sp_OAMethod @ssh, 'Disconnect', NULL

    EXEC @hr = sp_OADestroy @ssh


END
GO