import java.io.*;

import java.util.*;

import java.net.*;

import java.security.*;

import sun.net.www.*;

public class B6870935 {

static char[] passwd = "password".toCharArray();

static String username = "user";

static String nonce = "abcdefghijklmnopqrstuvwxyz";

static String realm = "wallyworld";

static String uri = "http://www.ibm.com";

static volatile boolean error = false;

static class DigestServer extends Thread {

ServerSocket s;

InputStream is;

OutputStream os;

int port;

String reply1 = "HTTP/1.1 407 Proxy Authentication Required\r\n"+

"Proxy-Authenticate: Digest realm=\""+realm+"\" domain=/ "+

"nonce=\""+nonce+"\" qop=\"auth\"\r\n\r\n";

String reply2 = "HTTP/1.1 200 OK\r\n" +

"Date: Mon, 15 Jan 2001 12:18:21 GMT\r\n" +

"Server: Apache/1.3.14 (Unix)\r\n" +

"Content-Type: text/html; charset=iso-8859-1\r\n" +

"Transfer-encoding: chunked\r\n\r\n"+

"B\r\nHelloWorld1\r\n"+

"B\r\nHelloWorld2\r\n"+

"B\r\nHelloWorld3\r\n"+

"B\r\nHelloWorld4\r\n"+

"B\r\nHelloWorld5\r\n"+

"0\r\n"+

"Proxy-Authentication-Info: ";

DigestServer (ServerSocket y) {

s = y;

port = s.getLocalPort();

}

public void run () {

try {

Socket s1 = s.accept ();

is = s1.getInputStream ();

os = s1.getOutputStream ();

is.read ();

os.write (reply1.getBytes());

Thread.sleep (2000);

s1.close ();

s1 = s.accept ();

is = s1.getInputStream ();

os = s1.getOutputStream ();

is.read ();

// need to get the cnonce out of the response

MessageHeader header = new MessageHeader (is);

String raw = header.findValue ("Proxy-Authorization");

HeaderParser parser = new HeaderParser (raw);

String cnonce = parser.findValue ("cnonce");

String cnstring = parser.findValue ("nc");

String clientrsp = parser.findValue ("response");

String expected = computeDigest(

true, username,passwd,realm,

"GET", uri, nonce, cnonce, cnstring

);

if (!expected.equals(clientrsp)) {

s1.close ();

s.close ();

error = true;

return;

}

String reply = reply2 + getAuthorization (

realm, false, uri, "GET", cnonce,

cnstring, passwd, username

) +"\r\n";

os.write (reply.getBytes());

Thread.sleep (2000);

s1.close ();

}

catch (Exception e) {

System.out.println (e);

e.printStackTrace();

}

}

private String getAuthorization (String realm, boolean isRequest, String uri, String method, String cnonce, String cnstring, char[] password, String username) {

String response;

try {

response = computeDigest(isRequest, username,passwd,realm,

method, uri, nonce, cnonce, cnstring);

} catch (NoSuchAlgorithmException ex) {

return null;

}

String value = "Digest"

+ " qop=\"auth"

+ "\", cnonce=\"" + cnonce

+ "\", rspauth=\"" + response

+ "\", nc=\"" + cnstring + "\"";

return (value+ "\r\n");

}

private String computeDigest(

boolean isRequest, String userName, char[] password,

String realm, String connMethod,

String requestURI, String nonceString,

String cnonce, String ncValue

) throws NoSuchAlgorithmException

{

String A1, HashA1;

MessageDigest md = MessageDigest.getInstance("MD5");

{

A1 = userName + ":" + realm + ":";

HashA1 = encode(A1, password, md);

}

String A2;

if (isRequest) {

A2 = connMethod + ":" + requestURI;

} else {

A2 = ":" + requestURI;

}

String HashA2 = encode(A2, null, md);

String combo, finalHash;

{ /* RRC2617 when qop=auth */

combo = HashA1+ ":" + nonceString + ":" + ncValue + ":" +

cnonce + ":auth:" +HashA2;

}

finalHash = encode(combo, null, md);

return finalHash;

}

private final static char charArray[] = {

'0', '1', '2', '3', '4', '5', '6', '7',

'8', '9', 'a', 'b', 'c', 'd', 'e', 'f'

};

private String encode(String src, char[] passwd, MessageDigest md) {

md.update(src.getBytes());

if (passwd != null) {

byte[] passwdBytes = new byte[passwd.length];

for (int i=0; i<passwd.length; i++)

passwdBytes[i] = (byte)passwd[i];

md.update(passwdBytes);

Arrays.fill(passwdBytes, (byte)0x00);

}

byte[] digest = md.digest();

StringBuffer res = new StringBuffer(digest.length * 2);

for (int i = 0; i < digest.length; i++) {

int hashchar = ((digest[i] >>> 4) & 0xf);

res.append(charArray[hashchar]);

hashchar = (digest[i] & 0xf);

res.append(charArray[hashchar]);

}

return res.toString();

}

}

static class MyAuthenticator extends Authenticator {

public MyAuthenticator () {

super ();

}

public PasswordAuthentication getPasswordAuthentication ()

{

return (new PasswordAuthentication (username, passwd));

}

}

public static void main(String[] args) throws Exception {

int nLoops = 1;

int nSize = 10;

int port, n =0;

byte b[] = new byte[nSize];

DigestServer server;

ServerSocket sock;

try {

sock = new ServerSocket (0);

port = sock.getLocalPort ();

}

catch (Exception e) {

System.out.println ("Exception: " + e);

return;

}

server = new DigestServer(sock);

server.start ();

try {

Authenticator.setDefault (new MyAuthenticator ());

SocketAddress addr = new InetSocketAddress ("127.0.0.1", port);

Proxy proxy = new Proxy (Proxy.Type.HTTP, addr);

String s = "http://www.ibm.com";

URL url = new URL(s);

java.net.URLConnection conURL = url.openConnection(proxy);

InputStream in = conURL.getInputStream();

int c;

while ((c = in.read ()) != -1) {

}

in.close ();

}

catch(IOException e) {

e.printStackTrace();

error = true;

}

if (error) {

throw new RuntimeException ("Error in test");

}

}

}