KeyboardInteractiveAuthenticationMethod
Provides functionality to perform keyboard interactive authentication.
using Renci.SshNet.Abstractions;
using Renci.SshNet.Common;
using Renci.SshNet.Messages;
using Renci.SshNet.Messages.Authentication;
using System;
using System.Linq;
using System.Runtime.ExceptionServices;
using System.Threading;
namespace Renci.SshNet
{
public class KeyboardInteractiveAuthenticationMethod : AuthenticationMethod
{
private readonly RequestMessageKeyboardInteractive _requestMessage;
private AuthenticationResult _authenticationResult = AuthenticationResult.Failure;
private Session _session;
private EventWaitHandle _authenticationCompleted = new AutoResetEvent(false);
private Exception _exception;
private bool _isDisposed;
public override string Name => _requestMessage.MethodName;
public event EventHandler<AuthenticationPromptEventArgs> AuthenticationPrompt;
public KeyboardInteractiveAuthenticationMethod(string username)
: base(username)
{
_requestMessage = new RequestMessageKeyboardInteractive(ServiceName.Connection, username);
}
public override AuthenticationResult Authenticate(Session session)
{
_session = session;
session.UserAuthenticationSuccessReceived += Session_UserAuthenticationSuccessReceived;
session.UserAuthenticationFailureReceived += Session_UserAuthenticationFailureReceived;
session.UserAuthenticationInformationRequestReceived += Session_UserAuthenticationInformationRequestReceived;
session.RegisterMessage("SSH_MSG_USERAUTH_INFO_REQUEST");
try {
session.SendMessage(_requestMessage);
session.WaitOnHandle(_authenticationCompleted);
} finally {
session.UnRegisterMessage("SSH_MSG_USERAUTH_INFO_REQUEST");
session.UserAuthenticationSuccessReceived -= Session_UserAuthenticationSuccessReceived;
session.UserAuthenticationFailureReceived -= Session_UserAuthenticationFailureReceived;
session.UserAuthenticationInformationRequestReceived -= Session_UserAuthenticationInformationRequestReceived;
}
if (_exception != null)
ExceptionDispatchInfo.Capture(_exception).Throw();
return _authenticationResult;
}
private void Session_UserAuthenticationSuccessReceived(object sender, MessageEventArgs<SuccessMessage> e)
{
_authenticationResult = AuthenticationResult.Success;
_authenticationCompleted.Set();
}
private void Session_UserAuthenticationFailureReceived(object sender, MessageEventArgs<FailureMessage> e)
{
if (e.Message.PartialSuccess)
_authenticationResult = AuthenticationResult.PartialSuccess;
else
_authenticationResult = AuthenticationResult.Failure;
base.AllowedAuthentications = e.Message.AllowedAuthentications;
_authenticationCompleted.Set();
}
private void Session_UserAuthenticationInformationRequestReceived(object sender, MessageEventArgs<InformationRequestMessage> e)
{
InformationRequestMessage message = e.Message;
AuthenticationPromptEventArgs eventArgs = new AuthenticationPromptEventArgs(base.Username, message.Instruction, message.Language, message.Prompts);
ThreadAbstraction.ExecuteThread(delegate {
try {
this.AuthenticationPrompt?.Invoke(this, eventArgs);
InformationResponseMessage informationResponseMessage = new InformationResponseMessage();
foreach (AuthenticationPrompt item in from r in eventArgs.Prompts
orderby r.Id
select r) {
if (item.Response == null)
throw new SshAuthenticationException("AuthenticationPrompt.Response is null for prompt \"" + item.Request + "\". You can set this by subscribing to KeyboardInteractiveAuthenticationMethod.AuthenticationPrompt and inspecting the Prompts property of the event args.");
informationResponseMessage.Responses.Add(item.Response);
}
_session.SendMessage(informationResponseMessage);
} catch (Exception exception) {
_exception = exception;
_authenticationCompleted.Set();
}
});
}
protected override void Dispose(bool disposing)
{
if (!_isDisposed) {
if (disposing) {
EventWaitHandle authenticationCompleted = _authenticationCompleted;
if (authenticationCompleted != null) {
_authenticationCompleted = null;
authenticationCompleted.Dispose();
}
_isDisposed = true;
}
base.Dispose(disposing);
}
}
}
}