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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
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*
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
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package com.sun.security.auth.callback;
/* JAAS imports */
import javax.security.auth.callback.Callback;
import javax.security.auth.callback.CallbackHandler;
import javax.security.auth.callback.ConfirmationCallback;
import javax.security.auth.callback.NameCallback;
import javax.security.auth.callback.PasswordCallback;
import javax.security.auth.callback.TextOutputCallback;
import javax.security.auth.callback.UnsupportedCallbackException;
/* Java imports */
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PushbackInputStream;
import java.util.Arrays;
import sun.security.util.Password;
Prompts and reads from the command line for answers to authentication
questions.
This can be used by a JAAS application to instantiate a
CallbackHandler
See Also: - callback
/**
* <p>
* Prompts and reads from the command line for answers to authentication
* questions.
* This can be used by a JAAS application to instantiate a
* CallbackHandler
* @see javax.security.auth.callback
*/
public class TextCallbackHandler implements CallbackHandler {
Creates a callback handler that prompts and reads from the
command line for answers to authentication questions.
This can be used by JAAS applications to instantiate a
CallbackHandler.
/**
* <p>Creates a callback handler that prompts and reads from the
* command line for answers to authentication questions.
* This can be used by JAAS applications to instantiate a
* CallbackHandler.
*/
public TextCallbackHandler() { }
Handles the specified set of callbacks.
Params: - callbacks – the callbacks to handle
Throws: - IOException – if an input or output error occurs.
- UnsupportedCallbackException – if the callback is not an
instance of NameCallback or PasswordCallback
/**
* Handles the specified set of callbacks.
*
* @param callbacks the callbacks to handle
* @throws IOException if an input or output error occurs.
* @throws UnsupportedCallbackException if the callback is not an
* instance of NameCallback or PasswordCallback
*/
public void handle(Callback[] callbacks)
throws IOException, UnsupportedCallbackException
{
ConfirmationCallback confirmation = null;
for (int i = 0; i < callbacks.length; i++) {
if (callbacks[i] instanceof TextOutputCallback) {
TextOutputCallback tc = (TextOutputCallback) callbacks[i];
String text;
switch (tc.getMessageType()) {
case TextOutputCallback.INFORMATION:
text = "";
break;
case TextOutputCallback.WARNING:
text = "Warning: ";
break;
case TextOutputCallback.ERROR:
text = "Error: ";
break;
default:
throw new UnsupportedCallbackException(
callbacks[i], "Unrecognized message type");
}
String message = tc.getMessage();
if (message != null) {
text += message;
}
if (text != null) {
System.err.println(text);
}
} else if (callbacks[i] instanceof NameCallback) {
NameCallback nc = (NameCallback) callbacks[i];
if (nc.getDefaultName() == null) {
System.err.print(nc.getPrompt());
} else {
System.err.print(nc.getPrompt() +
" [" + nc.getDefaultName() + "] ");
}
System.err.flush();
String result = readLine();
if (result.equals("")) {
result = nc.getDefaultName();
}
nc.setName(result);
} else if (callbacks[i] instanceof PasswordCallback) {
PasswordCallback pc = (PasswordCallback) callbacks[i];
System.err.print(pc.getPrompt());
System.err.flush();
pc.setPassword(Password.readPassword(System.in, pc.isEchoOn()));
} else if (callbacks[i] instanceof ConfirmationCallback) {
confirmation = (ConfirmationCallback) callbacks[i];
} else {
throw new UnsupportedCallbackException(
callbacks[i], "Unrecognized Callback");
}
}
/* Do the confirmation callback last. */
if (confirmation != null) {
doConfirmation(confirmation);
}
}
/* Reads a line of input */
private String readLine() throws IOException {
String result = new BufferedReader
(new InputStreamReader(System.in)).readLine();
if (result == null) {
throw new IOException("Cannot read from System.in");
}
return result;
}
private void doConfirmation(ConfirmationCallback confirmation)
throws IOException, UnsupportedCallbackException
{
String prefix;
int messageType = confirmation.getMessageType();
switch (messageType) {
case ConfirmationCallback.WARNING:
prefix = "Warning: ";
break;
case ConfirmationCallback.ERROR:
prefix = "Error: ";
break;
case ConfirmationCallback.INFORMATION:
prefix = "";
break;
default:
throw new UnsupportedCallbackException(
confirmation, "Unrecognized message type: " + messageType);
}
class OptionInfo {
String name;
int value;
OptionInfo(String name, int value) {
this.name = name;
this.value = value;
}
}
OptionInfo[] options;
int optionType = confirmation.getOptionType();
switch (optionType) {
case ConfirmationCallback.YES_NO_OPTION:
options = new OptionInfo[] {
new OptionInfo("Yes", ConfirmationCallback.YES),
new OptionInfo("No", ConfirmationCallback.NO)
};
break;
case ConfirmationCallback.YES_NO_CANCEL_OPTION:
options = new OptionInfo[] {
new OptionInfo("Yes", ConfirmationCallback.YES),
new OptionInfo("No", ConfirmationCallback.NO),
new OptionInfo("Cancel", ConfirmationCallback.CANCEL)
};
break;
case ConfirmationCallback.OK_CANCEL_OPTION:
options = new OptionInfo[] {
new OptionInfo("OK", ConfirmationCallback.OK),
new OptionInfo("Cancel", ConfirmationCallback.CANCEL)
};
break;
case ConfirmationCallback.UNSPECIFIED_OPTION:
String[] optionStrings = confirmation.getOptions();
options = new OptionInfo[optionStrings.length];
for (int i = 0; i < options.length; i++) {
options[i] = new OptionInfo(optionStrings[i], i);
}
break;
default:
throw new UnsupportedCallbackException(
confirmation, "Unrecognized option type: " + optionType);
}
int defaultOption = confirmation.getDefaultOption();
String prompt = confirmation.getPrompt();
if (prompt == null) {
prompt = "";
}
prompt = prefix + prompt;
if (!prompt.equals("")) {
System.err.println(prompt);
}
for (int i = 0; i < options.length; i++) {
if (optionType == ConfirmationCallback.UNSPECIFIED_OPTION) {
// defaultOption is an index into the options array
System.err.println(
i + ". " + options[i].name +
(i == defaultOption ? " [default]" : ""));
} else {
// defaultOption is an option value
System.err.println(
i + ". " + options[i].name +
(options[i].value == defaultOption ? " [default]" : ""));
}
}
System.err.print("Enter a number: ");
System.err.flush();
int result;
try {
result = Integer.parseInt(readLine());
if (result < 0 || result > (options.length - 1)) {
result = defaultOption;
}
result = options[result].value;
} catch (NumberFormatException e) {
result = defaultOption;
}
confirmation.setSelectedIndex(result);
}
}