| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| package org.apache.sshd.client.auth.keyboard; |
| |
| import java.security.KeyPair; |
| import java.util.List; |
| |
| import org.apache.sshd.client.session.ClientSession; |
| import org.apache.sshd.common.util.GenericUtils; |
| |
| /** |
| * Interface used by the ssh client to communicate with the end user. |
| * |
| * @author <a href="mailto:dev@mina.apache.org">Apache MINA SSHD Project</a> |
| * @see <a href="https://tools.ietf.org/html/rfc4256">RFC 4256</A> |
| */ |
| public interface UserInteraction { |
| /** |
| * Whether to auto-detect password challenge prompt |
| * |
| * @see #INTERACTIVE_PASSWORD_PROMPT |
| * @see #CHECK_INTERACTIVE_PASSWORD_DELIM |
| */ |
| String AUTO_DETECT_PASSWORD_PROMPT = "user-interaction-auto-detect-password-prompt"; |
| |
| /** Default value for {@value #AUTO_DETECT_PASSWORD_PROMPT} */ |
| boolean DEFAULT_AUTO_DETECT_PASSWORD_PROMPT = true; |
| |
| /** |
| * Comma separated list of values used to detect request for a password in interactive mode. <B>Note:</B> the |
| * matched prompt is assumed to be <U>lowercase</U>. |
| */ |
| String INTERACTIVE_PASSWORD_PROMPT = "user-interaction-password-prompt"; |
| |
| /** Default value for {@value #INTERACTIVE_PASSWORD_PROMPT} */ |
| String DEFAULT_INTERACTIVE_PASSWORD_PROMPT = "password"; |
| |
| /** |
| * If password prompt detected then check it ends with <U>any</U> of the comma separated list of these values. Use |
| * "none" to disable this extra check. <B>Note:</B> the matched prompt is assumed to be <U>lowercase</U>. |
| */ |
| String CHECK_INTERACTIVE_PASSWORD_DELIM = "user-interaction-check-password-delimiter"; |
| |
| /** Default value of {@value #CHECK_INTERACTIVE_PASSWORD_DELIM} */ |
| String DEFAULT_CHECK_INTERACTIVE_PASSWORD_DELIM = ":"; |
| |
| /** |
| * A useful "placeholder" that indicates that no interaction is expected. <B>Note:</B> throws |
| * {@link IllegalStateException} is any of the interaction methods is called |
| */ |
| UserInteraction NONE = new UserInteraction() { |
| @Override |
| public boolean isInteractionAllowed(ClientSession session) { |
| return false; |
| } |
| |
| @Override |
| public String[] interactive( |
| ClientSession session, String name, String instruction, |
| String lang, String[] prompt, boolean[] echo) { |
| throw new IllegalStateException("interactive(" + session + ")[" + name + "] unexpected call"); |
| } |
| |
| @Override |
| public String getUpdatedPassword(ClientSession session, String prompt, String lang) { |
| throw new IllegalStateException("getUpdatedPassword(" + session + ")[" + prompt + "] unexpected call"); |
| } |
| |
| @Override |
| public String toString() { |
| return "NONE"; |
| } |
| }; |
| |
| /** |
| * @param session The {@link ClientSession} |
| * @return {@code true} if user interaction allowed for this session (default) |
| */ |
| default boolean isInteractionAllowed(ClientSession session) { |
| return true; |
| } |
| |
| /** |
| * Called if the server sent any extra information beyond the standard version line |
| * |
| * @param session The {@link ClientSession} through which this information was received |
| * @param lines The sent extra lines - <U>without</U> the server version |
| * @see <A HREF="https://tools.ietf.org/html/rfc4253#section-4.2">RFC 4253 - section 4.2</A> |
| */ |
| default void serverVersionInfo(ClientSession session, List<String> lines) { |
| // do nothing |
| } |
| |
| /** |
| * Displays the welcome banner to the user. |
| * |
| * @param session The {@link ClientSession} through which the banner was received |
| * @param banner The welcome banner |
| * @param lang The banner language code - may be empty |
| */ |
| default void welcome(ClientSession session, String banner, String lang) { |
| // do nothing |
| } |
| |
| /** |
| * Invoked when "keyboard-interactive" authentication mechanism is used in order to provide responses for |
| * the server's challenges (a.k.a. prompts) |
| * |
| * @param session The {@link ClientSession} through which the request was received |
| * @param name The interaction name (may be empty) |
| * @param instruction The instruction (may be empty) |
| * @param lang The language for the data (may be empty) |
| * @param prompt The prompts to be displayed (may be empty) |
| * @param echo For each prompt whether to echo the user's response |
| * @return The replies - <B>Note:</B> the protocol states that the number of replies should be |
| * <U>exactly</U> the same as the number of prompts, however we do not enforce it since it is |
| * defined as the <U>server's</U> job to check and manage this violation. |
| */ |
| String[] interactive( |
| ClientSession session, String name, String instruction, String lang, String[] prompt, boolean[] echo); |
| |
| /** |
| * Invoked when the server returns an {@code SSH_MSG_USERAUTH_PASSWD_CHANGEREQ} response indicating that the |
| * password should be changed - e.g., expired or not strong enough (as per the server's policy). |
| * |
| * @param session The {@link ClientSession} through which the request was received |
| * @param prompt The server's prompt (may be empty) |
| * @param lang The prompt's language (may be empty) |
| * @return The password to use - if {@code null}/empty then no updated password was provided - thus failing |
| * the authentication via passwords (<B>Note:</B> authentication might still succeed via some other |
| * means - be it other passwords, public keys, etc...) |
| */ |
| String getUpdatedPassword(ClientSession session, String prompt, String lang); |
| |
| /** |
| * Invoked during password authentication when no more pre-registered passwords are available |
| * |
| * @param session The {@link ClientSession} through which the request was received |
| * @return The password to use - {@code null} signals no more passwords available |
| * @throws Exception if failed to handle the request - <B>Note:</B> may cause session termination |
| */ |
| default String resolveAuthPasswordAttempt(ClientSession session) throws Exception { |
| return null; |
| } |
| |
| /** |
| * Invoked during public key authentication when no more pre-registered keys are available |
| * |
| * @param session The {@link ClientSession} through which the request was received |
| * @return The {@link KeyPair} to use - {@code null} signals no more keys available |
| * @throws Exception if failed to handle the request - <B>Note:</B> may cause session termination |
| */ |
| default KeyPair resolveAuthPublicKeyIdentityAttempt(ClientSession session) throws Exception { |
| return null; |
| } |
| |
| /** |
| * @param prompt The user interaction prompt |
| * @param tokensList A comma-separated list of tokens whose <U>last</U> index is prompt is sought. |
| * @return The position of any token in the prompt - negative if not found |
| */ |
| static int findPromptComponentLastPosition(String prompt, String tokensList) { |
| if (GenericUtils.isEmpty(prompt) || GenericUtils.isEmpty(tokensList)) { |
| return -1; |
| } |
| |
| String[] tokens = GenericUtils.split(tokensList, ','); |
| for (String t : tokens) { |
| int pos = prompt.lastIndexOf(t); |
| if (pos >= 0) { |
| return pos; |
| } |
| } |
| |
| return -1; |
| } |
| } |
