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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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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
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package sun.net.www.protocol.http.ntlm;

import com.sun.security.ntlm.Client;
import com.sun.security.ntlm.NTLMException;
import java.io.IOException;
import java.net.InetAddress;
import java.net.PasswordAuthentication;
import java.net.UnknownHostException;
import java.net.URL;
import java.security.GeneralSecurityException;
import java.util.Base64;
import java.util.Objects;
import java.util.Properties;

import sun.net.www.HeaderParser;
import sun.net.www.protocol.http.AuthenticationInfo;
import sun.net.www.protocol.http.AuthScheme;
import sun.net.www.protocol.http.HttpURLConnection;
import sun.security.action.GetPropertyAction;

NTLMAuthentication:
Author:
Michael McMahon/**
 * NTLMAuthentication:
 *
 * @author Michael McMahon
 */

/*
 * NTLM authentication is nominally based on the framework defined in RFC2617,
 * but differs from the standard (Basic & Digest) schemes as follows:
 *
 * 1. A complete authentication requires three request/response transactions
 *    as shown below:
 *            REQ ------------------------------->
 *            <---- 401 (signalling NTLM) --------
 *
 *            REQ (with type1 NTLM msg) --------->
 *            <---- 401 (with type 2 NTLM msg) ---
 *
 *            REQ (with type3 NTLM msg) --------->
 *            <---- OK ---------------------------
 *
 * 2. The scope of the authentication is the TCP connection (which must be kept-alive)
 *    after the type2 response is received. This means that NTLM does not work end-to-end
 *    through a proxy, rather between client and proxy, or between client and server (with no proxy)
 */

public class NTLMAuthentication extends AuthenticationInfo {
    private static final long serialVersionUID = 170L;

    private static final NTLMAuthenticationCallback NTLMAuthCallback =
        NTLMAuthenticationCallback.getNTLMAuthenticationCallback();

    private String hostname;
    /* Domain to use if not specified by user */
    private static final String defaultDomain;
    /* Whether cache is enabled for NTLM */
    private static final boolean ntlmCache;
    static {
        Properties props = GetPropertyAction.privilegedGetProperties();
        defaultDomain = props.getProperty("http.auth.ntlm.domain", "");
        String ntlmCacheProp = props.getProperty("jdk.ntlm.cache", "true");
        ntlmCache = Boolean.parseBoolean(ntlmCacheProp);
    }

    public static boolean supportsTransparentAuth () {
        return false;
    }

    
Returns true if the given site is trusted, i.e. we can try
transparent Authentication. Shouldn't be called since
capability not supported on Unix
/**
     * Returns true if the given site is trusted, i.e. we can try
     * transparent Authentication. Shouldn't be called since
     * capability not supported on Unix
     */
    public static boolean isTrustedSite(URL url) {
        if (NTLMAuthCallback != null)
            return NTLMAuthCallback.isTrustedSite(url);
        return false;
    }

    private void init0() {

        hostname = java.security.AccessController.doPrivileged(
            new java.security.PrivilegedAction<>() {
            public String run() {
                String localhost;
                try {
                    localhost = InetAddress.getLocalHost().getHostName();
                } catch (UnknownHostException e) {
                     localhost = "localhost";
                }
                return localhost;
            }
        });
    };

    PasswordAuthentication pw;

    Client client;
    
Create a NTLMAuthentication: Username may be specified as domain<BACKSLASH>username in the application Authenticator. If this notation is not used, then the domain will be taken from a system property: "http.auth.ntlm.domain". /**
     * Create a NTLMAuthentication:
     * Username may be specified as {@literal domain<BACKSLASH>username}
     * in the application Authenticator.
     * If this notation is not used, then the domain will be taken
     * from a system property: "http.auth.ntlm.domain".
     */
    public NTLMAuthentication(boolean isProxy, URL url, PasswordAuthentication pw,
                              String authenticatorKey) {
        super(isProxy ? PROXY_AUTHENTICATION : SERVER_AUTHENTICATION,
                AuthScheme.NTLM,
                url,
                "",
                Objects.requireNonNull(authenticatorKey));
        init (pw);
    }

    private void init (PasswordAuthentication pw) {
        String username;
        String ntdomain;
        char[] password;
        this.pw = pw;
        String s = pw.getUserName();
        int i = s.indexOf ('\\');
        if (i == -1) {
            username = s;
            ntdomain = defaultDomain;
        } else {
            ntdomain = s.substring (0, i).toUpperCase();
            username = s.substring (i+1);
        }
        password = pw.getPassword();
        init0();
        try {
            String version = GetPropertyAction.privilegedGetProperty("ntlm.version");
            client = new Client(version, hostname, username, ntdomain, password);
        } catch (NTLMException ne) {
            try {
                client = new Client(null, hostname, username, ntdomain, password);
            } catch (NTLMException ne2) {
                // Will never happen
                throw new AssertionError("Really?");
            }
        }
    }

   
Constructor used for proxy entries
/**
    * Constructor used for proxy entries
    */
    public NTLMAuthentication(boolean isProxy, String host, int port,
                              PasswordAuthentication pw,
                              String authenticatorKey) {
        super(isProxy ? PROXY_AUTHENTICATION : SERVER_AUTHENTICATION,
                AuthScheme.NTLM,
                host,
                port,
                "",
                Objects.requireNonNull(authenticatorKey));
        init (pw);
    }

    @Override
    protected boolean useAuthCache() {
        return ntlmCache && super.useAuthCache();
    }

    
Returns:
true if this authentication supports preemptive authorization/**
     * @return true if this authentication supports preemptive authorization
     */
    @Override
    public boolean supportsPreemptiveAuthorization() {
        return false;
    }

    
Not supported. Must use the setHeaders() method
/**
     * Not supported. Must use the setHeaders() method
     */
    @Override
    public String getHeaderValue(URL url, String method) {
        throw new RuntimeException ("getHeaderValue not supported");
    }

    
Check if the header indicates that the current auth. parameters are stale.
If so, then replace the relevant field with the new value
and return true. Otherwise return false.
returning true means the request can be retried with the same userid/password
returning false means we have to go back to the user to ask for a new
username password.
/**
     * Check if the header indicates that the current auth. parameters are stale.
     * If so, then replace the relevant field with the new value
     * and return true. Otherwise return false.
     * returning true means the request can be retried with the same userid/password
     * returning false means we have to go back to the user to ask for a new
     * username password.
     */
    @Override
    public boolean isAuthorizationStale (String header) {
        return false; /* should not be called for ntlm */
    }

    
Set header(s) on the given connection.
Params:
conn – The connection to apply the header(s) to
p – A source of header values for this connection, not used because
         HeaderParser converts the fields to lower case, use raw instead
raw – The raw header field.
Returns:
true if all goes well, false if no headers were set./**
     * Set header(s) on the given connection.
     * @param conn The connection to apply the header(s) to
     * @param p A source of header values for this connection, not used because
     *          HeaderParser converts the fields to lower case, use raw instead
     * @param raw The raw header field.
     * @return true if all goes well, false if no headers were set.
     */
    @Override
    public boolean setHeaders(HttpURLConnection conn, HeaderParser p, String raw) {
        // no need to synchronize here:
        //   already locked by s.n.w.p.h.HttpURLConnection
        assert conn.isLockHeldByCurrentThread();

        try {
            String response;
            if (raw.length() < 6) { /* NTLM<sp> */
                response = buildType1Msg ();
            } else {
                String msg = raw.substring (5); /* skip NTLM<sp> */
                response = buildType3Msg (msg);
            }
            conn.setAuthenticationProperty(getHeaderName(), response);
            return true;
        } catch (IOException e) {
            return false;
        } catch (GeneralSecurityException e) {
            return false;
        }
    }

    private String buildType1Msg () {
        byte[] msg = client.type1();
        String result = "NTLM " + Base64.getEncoder().encodeToString(msg);
        return result;
    }

    private String buildType3Msg (String challenge) throws GeneralSecurityException,
                                                           IOException  {
        /* First decode the type2 message to get the server nonce */
        /* nonce is located at type2[24] for 8 bytes */

        byte[] type2 = Base64.getDecoder().decode(challenge);
        byte[] nonce = new byte[8];
        new java.util.Random().nextBytes(nonce);
        byte[] msg = client.type3(type2, nonce);
        String result = "NTLM " + Base64.getEncoder().encodeToString(msg);
        return result;
    }
}