C#

Using sudo in an SSH Shell Session

See more SSH Examples

Demonstrates how to run a command as sudo in a shell session. C#

bool success = false;

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

Chilkat.Ssh ssh = new Chilkat.Ssh();

int port = 22;
success = ssh.Connect("the-ssh-server.com",port);
if (success != true) {
    Debug.WriteLine(ssh.LastErrorText);
    return;
}

//  Authenticate using login/password:
success = ssh.AuthenticatePw("theSshLogin","theSshPassword");
if (success != true) {
    Debug.WriteLine(ssh.LastErrorText);
    return;
}

//  Start a shell session.
//  (The QuickShell method was added in Chilkat v9.5.0.65)
int channelNum = ssh.QuickShell();
if (channelNum < 0) {
    Debug.WriteLine(ssh.LastErrorText);
    return;
}

//  Construct a StringBuilder with our command ("ls") run with "sudo"
//  Note: The line-endings are potentially important.  Some SSH servers may
//  require either LF or CRLF line endings.  (Unix/Linux/OSX servers typically
//  use bare-LF line endings.  Windows servers likely use CRLF line endings.)

//  Using "sudo -S" causes the sudo prompt to be written to stderr,
//  and the password is read from stdin (i.e. from the echo command ouput).
//  The sudo commands -p option allows us to set the prompt, and we can set it to
//  the empty string, thus eliminating the prompt from the stderr completely.
//  This allows us to run the command as root (super-user) with no prompt.
Chilkat.StringBuilder sbCommands = new Chilkat.StringBuilder();
sbCommands.Append("echo \"theSshPassword\" | sudo -S -p \"\" ls\n");

//  Add another command to echo a marker string that
//  we'll use in ChannelReceiveUntilMatch below.
//  The use of single quotes around 'IS' is a trick so that the output
//  of the command is "THIS IS THE END OF THE SCRIPT", but the terminal echo
//  includes the single quotes.  This allows us to read until we see the actual
//  output of the last command.
sbCommands.Append("echo THIS 'IS' THE END OF THE SCRIPT\n");

//  Send the commands..
success = ssh.ChannelSendString(channelNum,sbCommands.GetAsString(),"ansi");
if (success != true) {
    Debug.WriteLine(ssh.LastErrorText);
    return;
}

//  Send an EOF to indicate no more commands will be sent.
//  For brevity, we're not checking the return values of each method call.
//  Your code should check the success/failure of each call.
success = ssh.ChannelSendEof(channelNum);

//  Receive output up to our marker.
success = ssh.ChannelReceiveUntilMatch(channelNum,"THIS IS THE END OF THE SCRIPT","ansi",true);

//  Close the channel.
//  It is important to close the channel only after receiving the desired output.
success = ssh.ChannelSendClose(channelNum);

//  Get any remaining output..
success = ssh.ChannelReceiveToClose(channelNum);

//  Get the complete output for all the commands in the session.
Debug.WriteLine("--- output ----");
Debug.WriteLine(ssh.GetReceivedText(channelNum,"ansi"));