Java 类org.apache.http.auth.MalformedChallengeException 实例源码

@Override
protected void parseChallenge(
                               final CharArrayBuffer buffer,
                               int beginIndex,
                               int endIndex ) throws MalformedChallengeException {

    String challenge = buffer.substringTrimmed(beginIndex, endIndex);
    if (log.isDebugEnabled()) {
        log.debug("Received challenge '" + challenge + "' from the auth server");
    }
    if (state == State.UNINITIATED) {
        token = base64codec.decode(challenge.getBytes());
        state = State.CHALLENGE_RECEIVED;
    } else {
        log.debug("Authentication already attempted");
        state = State.FAILED;
    }
}

@Override
protected void parseChallenge(
        final CharArrayBuffer buffer,
        int beginIndex, int endIndex) throws MalformedChallengeException {
    String challenge = buffer.substringTrimmed(beginIndex, endIndex);
    if (challenge.length() == 0) {
        if (this.state == State.UNINITIATED) {
            this.state = State.CHALLENGE_RECEIVED;
        } else {
            this.state = State.FAILED;
        }
        this.challenge = null;
    } else {
        this.state = State.MSG_TYPE2_RECEVIED;
        this.challenge = challenge;
    }
}

@Override
protected void parseChallenge(
        final CharArrayBuffer buffer,
        int beginIndex, int endIndex) throws MalformedChallengeException {
    String challenge = buffer.substringTrimmed(beginIndex, endIndex);
    if (log.isDebugEnabled()) {
        log.debug("Received challenge '" + challenge + "' from the auth server");
    }
    if (state == State.UNINITIATED) {
        token = base64codec.decode(challenge.getBytes());
        state = State.CHALLENGE_RECEIVED;
    } else {
        log.debug("Authentication already attempted");
        state = State.FAILED;
    }
}

@Override
protected void parseChallenge(
        final CharArrayBuffer buffer,
        final int beginIndex, final int endIndex) throws MalformedChallengeException {
    this.challenge = buffer.substringTrimmed(beginIndex, endIndex);
    if (this.challenge.length() == 0) {
        if (this.state == State.UNINITIATED) {
            this.state = State.CHALLENGE_RECEIVED;
        } else {
            this.state = State.FAILED;
        }
    } else {
        if (this.state.compareTo(State.MSG_TYPE1_GENERATED) < 0) {
            this.state = State.FAILED;
            throw new MalformedChallengeException("Out of sequence NTLM response message");
        } else if (this.state == State.MSG_TYPE1_GENERATED) {
            this.state = State.MSG_TYPE2_RECEVIED;
        }
    }
}

@Override
protected void parseChallenge(
        final CharArrayBuffer buffer,
        final int beginIndex, final int endIndex) throws MalformedChallengeException {
    this.challenge = buffer.substringTrimmed(beginIndex, endIndex);
    if (this.challenge.isEmpty()) {
        if (this.state == State.UNINITIATED) {
            this.state = State.CHALLENGE_RECEIVED;
        } else {
            this.state = State.FAILED;
        }
    } else {
        if (this.state.compareTo(State.MSG_TYPE1_GENERATED) < 0) {
            this.state = State.FAILED;
            throw new MalformedChallengeException("Out of sequence NTLM response message");
        } else if (this.state == State.MSG_TYPE1_GENERATED) {
            this.state = State.MSG_TYPE2_RECEVIED;
        }
    }
}

@Override
protected void parseChallenge(
        final CharArrayBuffer buffer,
        final int beginIndex, final int endIndex) throws MalformedChallengeException {
    final String challenge = buffer.substringTrimmed(beginIndex, endIndex);
    if (log.isDebugEnabled()) {
        log.debug("Received challenge '" + challenge + "' from the auth server");
    }
    if (state == State.UNINITIATED) {
        token = Base64.decodeBase64(challenge.getBytes());
        state = State.CHALLENGE_RECEIVED;
    } else {
        log.debug("Authentication already attempted");
        state = State.FAILED;
    }
}

@Test
public void testAuthenticationException() throws Exception {
    final HttpHost host = new HttpHost("somehost", 80);
    final HttpResponse response = new BasicHttpResponse(HttpVersion.HTTP_1_1, HttpStatus.SC_UNAUTHORIZED, "UNAUTHORIZED");

    this.authState.setState(AuthProtocolState.CHALLENGED);

    Mockito.doThrow(new MalformedChallengeException()).when(this.defltAuthStrategy).getChallenges(
            Mockito.any(HttpHost.class),
            Mockito.any(HttpResponse.class),
            Mockito.any(HttpContext.class));

    Assert.assertFalse(this.httpAuthenticator.handleAuthChallenge(host,
            response, this.defltAuthStrategy, this.authState, this.context));

    Assert.assertEquals(AuthProtocolState.UNCHALLENGED, this.authState.getState());
    Assert.assertNull(this.authState.getAuthScheme());
    Assert.assertNull(this.authState.getCredentials());
}

@Override
protected void parseChallenge(
        final CharArrayBuffer buffer,
        final int beginIndex,
        final int endIndex) throws MalformedChallengeException {
    this.challenge = buffer.substringTrimmed(beginIndex, endIndex);

    if (this.challenge.isEmpty()) {
        if (clientCred != null) {
            dispose(); // run cleanup first before throwing an exception otherwise can leak OS resources
            if (continueNeeded) {
                throw new RuntimeException("Unexpected token");
            }
        }
    }
}

@Override
protected void parseChallenge(
        final CharArrayBuffer buffer,
        final int beginIndex, final int endIndex) throws MalformedChallengeException {
    this.challenge = buffer.substringTrimmed(beginIndex, endIndex);
    if (this.challenge.length() == 0) {
        if (this.state == State.UNINITIATED) {
            this.state = State.CHALLENGE_RECEIVED;
        } else {
            this.state = State.FAILED;
        }
    } else {
        if (this.state.compareTo(State.MSG_TYPE1_GENERATED) < 0) {
            this.state = State.FAILED;
            throw new MalformedChallengeException("Out of sequence NTLM response message");
        } else if (this.state == State.MSG_TYPE1_GENERATED) {
            this.state = State.MSG_TYPE2_RECEVIED;
        }
    }
}

@Override
public Queue<AuthOption> select(final Map<String, Header> challengeHeaders,
                                final HttpHost authhost,
                                final HttpResponse response,
                                final HttpContext context)
        throws MalformedChallengeException {
    final HttpClientContext httpClientContext = HttpClientContext.adapt(context);
    final AuthState state = httpClientContext.getTargetAuthState();
    final Queue<AuthOption> queue = new LinkedList<>();

    if (state == null || !state.getState().equals(AuthProtocolState.CHALLENGED)) {
        queue.add(authOption);
    } else {
        System.out.println("does this happen?");
    }

    return queue;
}

private void processChallenges(
    final Map<String, Header> challenges,
    final AuthState authState,
    final AuthenticationHandler authHandler,
    final HttpResponse response,
    final HttpContext context)
      throws MalformedChallengeException, AuthenticationException {

  AuthScheme authScheme = authState.getAuthScheme();
  if (authScheme == null) {
    // Authentication not attempted before
    authScheme = authHandler.selectScheme(challenges, response, context);
    authState.setAuthScheme(authScheme);
  }
  String id = authScheme.getSchemeName();

  Header challenge = challenges.get(id.toLowerCase(Locale.ENGLISH));
  if (challenge == null) {
    throw new AuthenticationException(id +
      " authorization challenge expected, but not found");
  }
  authScheme.processChallenge(challenge);
  this.log.debug("Authorization challenge processed");
}

@Override
protected void parseChallenge(
        final CharArrayBuffer buffer, int pos, int len) throws MalformedChallengeException {
    String challenge = buffer.substringTrimmed(pos, len);
    if (challenge.length() == 0) {
        if (this.state == State.UNINITIATED) {
            this.state = State.CHALLENGE_RECEIVED;
        } else {
            this.state = State.FAILED;
        }
        this.challenge = null;
    } else {
        this.state = State.MSG_TYPE2_RECEVIED;
        this.challenge = challenge;
    }
}

private void processChallenges(
        final Map<String, Header> challenges, 
        final AuthState authState,
        final AuthenticationHandler authHandler,
        final HttpResponse response, 
        final HttpContext context) 
            throws MalformedChallengeException, AuthenticationException {

    AuthScheme authScheme = authState.getAuthScheme();
    if (authScheme == null) {
        // Authentication not attempted before
        authScheme = authHandler.selectScheme(challenges, response, context);
        authState.setAuthScheme(authScheme);
    }
    String id = authScheme.getSchemeName();

    Header challenge = challenges.get(id.toLowerCase(Locale.ENGLISH));
    if (challenge == null) {
        throw new AuthenticationException(id + 
            " authorization challenge expected, but not found");
    }
    authScheme.processChallenge(challenge);
    this.log.debug("Authorization challenge processed");
}

@Override
protected void parseChallenge(
        final CharArrayBuffer buffer,
        final int beginIndex, final int endIndex) throws MalformedChallengeException {
    this.challenge = buffer.substringTrimmed(beginIndex, endIndex);
    if (this.challenge.length() == 0) {
        if (this.state == State.UNINITIATED) {
            this.state = State.CHALLENGE_RECEIVED;
        } else {
            this.state = State.FAILED;
        }
    } else {
        if (this.state.compareTo(State.MSG_TYPE1_GENERATED) < 0) {
            this.state = State.FAILED;
            throw new MalformedChallengeException("Out of sequence NTLM response message");
        } else if (this.state == State.MSG_TYPE1_GENERATED) {
            this.state = State.MSG_TYPE2_RECEVIED;
        }
    }
}

private void processChallenges(
        final Map<String, Header> challenges,
        final AuthState authState,
        final AuthenticationHandler authHandler,
        final HttpResponse response,
        final HttpContext context)
            throws MalformedChallengeException, AuthenticationException {

    AuthScheme authScheme = authState.getAuthScheme();
    if (authScheme == null) {
        // Authentication not attempted before
        authScheme = authHandler.selectScheme(challenges, response, context);
        authState.setAuthScheme(authScheme);
    }
    String id = authScheme.getSchemeName();

    Header challenge = challenges.get(id.toLowerCase(Locale.ENGLISH));
    if (challenge == null) {
        throw new AuthenticationException(id +
            " authorization challenge expected, but not found");
    }
    authScheme.processChallenge(challenge);
    if (DEBUG) {
        Logger.debug("Authorization challenge processed");
    }
}

private void processChallenges(
        final Map<String, Header> challenges,
        final AuthState authState,
        final AuthenticationHandler authHandler,
        final HttpResponse response,
        final HttpContext context)
            throws MalformedChallengeException, AuthenticationException {

    AuthScheme authScheme = authState.getAuthScheme();
    if (authScheme == null) {
        // Authentication not attempted before
        authScheme = authHandler.selectScheme(challenges, response, context);
        authState.setAuthScheme(authScheme);
    }
    String id = authScheme.getSchemeName();

    Header challenge = challenges.get(id.toLowerCase(Locale.ENGLISH));
    if (challenge == null) {
        throw new AuthenticationException(id +
            " authorization challenge expected, but not found");
    }
    authScheme.processChallenge(challenge);
    if (Constants.DEBUG) {
        logger.debug("Authorization challenge processed");
    }
}

@Override
protected void parseChallenge(
        final CharArrayBuffer buffer, int pos, int len) throws MalformedChallengeException {
    HeaderValueParser parser = BasicHeaderValueParser.DEFAULT;
    ParserCursor cursor = new ParserCursor(pos, buffer.length());
    HeaderElement[] elements = parser.parseElements(buffer, cursor);
    if (elements.length == 0) {
        throw new MalformedChallengeException("Authentication challenge is empty");
    }
    this.params.clear();
    for (HeaderElement element : elements) {
        this.params.put(element.getName(), element.getValue());
    }
}

public Map<String, Header> getChallenges(
        final HttpResponse response,
        final HttpContext context) throws MalformedChallengeException {
    if (response == null) {
        throw new IllegalArgumentException("HTTP response may not be null");
    }
    Header[] headers = response.getHeaders(AUTH.WWW_AUTH);
    return parseChallenges(headers);
}

public Map<String, Header> getChallenges(
        final HttpResponse response,
        final HttpContext context) throws MalformedChallengeException {
    if (response == null) {
        throw new IllegalArgumentException("HTTP response may not be null");
    }
    Header[] headers = response.getHeaders(AUTH.PROXY_AUTH);
    return parseChallenges(headers);
}

@Override
public Queue<AuthOption> select(final Map<String, Header> challenges, final HttpHost authhost, final HttpResponse response, final HttpContext context) throws MalformedChallengeException {
    final HttpClientContext clientContext = HttpClientContext.adapt(context);
    final Queue<AuthOption> options = new LinkedList<AuthOption>();
    final Lookup<AuthSchemeProvider> registry = clientContext.getAuthSchemeRegistry();
    if(registry == null) {
        return options;
    }
    final RequestConfig config = clientContext.getRequestConfig();
    Collection<String> authPrefs = config.getProxyPreferredAuthSchemes();
    if(authPrefs == null) {
        authPrefs = DEFAULT_SCHEME_PRIORITY;
    }
    if(log.isDebugEnabled()) {
        log.debug("Authentication schemes in the order of preference: " + authPrefs);
    }

    for(final String id : authPrefs) {
        final Header challenge = challenges.get(id.toLowerCase(Locale.ROOT));
        if(challenge != null) {
            final AuthSchemeProvider authSchemeProvider = registry.lookup(id);
            if(authSchemeProvider == null) {
                continue;
            }
            final AuthScheme authScheme = authSchemeProvider.create(context);
            authScheme.processChallenge(challenge);
            final Credentials saved = keychain.getCredentials(authhost.getHostName());
            if(StringUtils.isEmpty(saved.getPassword())) {
                try {
                    final Credentials input = prompt.prompt(bookmark,
                        StringUtils.EMPTY,
                        String.format("%s %s", LocaleFactory.localizedString("Login", "Login"), authhost.getHostName()),
                        authScheme.getRealm(),
                        new LoginOptions()
                            .icon(bookmark.getProtocol().disk())
                            .usernamePlaceholder(LocaleFactory.localizedString("Username", "Credentials"))
                            .passwordPlaceholder(LocaleFactory.localizedString("Password", "Credentials"))
                            .user(true).password(true)
                    );
                    if(input.isSaved()) {
                        context.setAttribute(PROXY_CREDENTIALS_INPUT_ID, input);
                    }
                    options.add(new AuthOption(authScheme, new NTCredentials(input.getUsername(), input.getPassword(),
                        preferences.getProperty("webdav.ntlm.workstation"), preferences.getProperty("webdav.ntlm.domain"))));
                }
                catch(LoginCanceledException ignored) {
                    // Ignore dismiss of prompt
                    throw new MalformedChallengeException(ignored.getMessage(), ignored);
                }
            }
            else {
                options.add(new AuthOption(authScheme, new NTCredentials(saved.getUsername(), saved.getPassword(),
                    preferences.getProperty("webdav.ntlm.workstation"), preferences.getProperty("webdav.ntlm.domain"))));
            }
        }
        else {
            if(log.isDebugEnabled()) {
                log.debug("Challenge for " + id + " authentication scheme not available");
                // Try again
            }
        }
    }
    return options;
}

@Override
protected void parseChallenge(
        final CharArrayBuffer buffer, final int pos, final int len) throws MalformedChallengeException {
    final HeaderValueParser parser = BasicHeaderValueParserHC4.INSTANCE;
    final ParserCursor cursor = new ParserCursor(pos, buffer.length());
    final HeaderElement[] elements = parser.parseElements(buffer, cursor);
    if (elements.length == 0) {
        throw new MalformedChallengeException("Authentication challenge is empty");
    }
    this.params.clear();
    for (final HeaderElement element : elements) {
        this.params.put(element.getName().toLowerCase(Locale.ENGLISH), element.getValue());
    }
}

public Queue<AuthOption> select(
        final Map<String, Header> challenges,
        final HttpHost authhost,
        final HttpResponse response,
        final HttpContext context) throws MalformedChallengeException {
    Args.notNull(challenges, "Map of auth challenges");
    Args.notNull(authhost, "Host");
    Args.notNull(response, "HTTP response");
    Args.notNull(context, "HTTP context");
    final HttpClientContext clientContext = HttpClientContext.adapt(context);

    final Queue<AuthOption> options = new LinkedList<AuthOption>();
    final Lookup<AuthSchemeProvider> registry = clientContext.getAuthSchemeRegistry();
    if (registry == null) {
        if (Log.isLoggable(TAG, Log.DEBUG)) {
            Log.d(TAG, "Auth scheme registry not set in the context");
        }
        return options;
    }
    final CredentialsProvider credsProvider = clientContext.getCredentialsProvider();
    if (credsProvider == null) {
        if (Log.isLoggable(TAG, Log.DEBUG)) {
            Log.d(TAG, "Credentials provider not set in the context");
        }
        return options;
    }
    final RequestConfig config = clientContext.getRequestConfig();
    Collection<String> authPrefs = getPreferredAuthSchemes(config);
    if (authPrefs == null) {
        authPrefs = DEFAULT_SCHEME_PRIORITY;
    }
    if (Log.isLoggable(TAG, Log.DEBUG)) {
        Log.d(TAG, "Authentication schemes in the order of preference: " + authPrefs);
    }

    for (final String id: authPrefs) {
        final Header challenge = challenges.get(id.toLowerCase(Locale.ENGLISH));
        if (challenge != null) {
            final AuthSchemeProvider authSchemeProvider = registry.lookup(id);
            if (authSchemeProvider == null) {
                if (Log.isLoggable(TAG, Log.WARN)) {
                    Log.w(TAG, "Authentication scheme " + id + " not supported");
                    // Try again
                }
                continue;
            }
            final AuthScheme authScheme = authSchemeProvider.create(context);
            authScheme.processChallenge(challenge);

            final AuthScope authScope = new AuthScope(
                    authhost.getHostName(),
                    authhost.getPort(),
                    authScheme.getRealm(),
                    authScheme.getSchemeName());

            final Credentials credentials = credsProvider.getCredentials(authScope);
            if (credentials != null) {
                options.add(new AuthOption(authScheme, credentials));
            }
        } else {
            if (Log.isLoggable(TAG, Log.DEBUG)) {
                Log.d(TAG, "Challenge for " + id + " authentication scheme not available");
                // Try again
            }
        }
    }
    return options;
}

@Override
public Map<String, Header> getChallenges(
        final HttpHost authhost,
        final HttpResponse response,
        final HttpContext context) throws MalformedChallengeException {
    return this.handler.getChallenges(response, context);
}

@Override
public Map<String, Header> getChallenges(
        final HttpResponse response,
        final HttpContext context) throws MalformedChallengeException {
    Args.notNull(response, "HTTP response");
    final Header[] headers = response.getHeaders(AUTH.WWW_AUTH);
    return parseChallenges(headers);
}

@Override
public Map<String, Header> getChallenges(
        final HttpResponse response,
        final HttpContext context) throws MalformedChallengeException {
    Args.notNull(response, "HTTP response");
    final Header[] headers = response.getHeaders(AUTH.PROXY_AUTH);
    return parseChallenges(headers);
}

@Override
protected void parseChallenge(
        final CharArrayBuffer buffer, final int pos, final int len) throws MalformedChallengeException {
    final HeaderValueParser parser = BasicHeaderValueParser.INSTANCE;
    final ParserCursor cursor = new ParserCursor(pos, buffer.length());
    final HeaderElement[] elements = parser.parseElements(buffer, cursor);
    this.params.clear();
    for (final HeaderElement element : elements) {
        this.params.put(element.getName().toLowerCase(Locale.ROOT), element.getValue());
    }
}

/**
 * Processes the Digest challenge.
 *
 * @param header the challenge header
 *
 * @throws MalformedChallengeException is thrown if the authentication challenge
 * is malformed
 */
@Override
public void processChallenge(
        final Header header) throws MalformedChallengeException {
    super.processChallenge(header);
    this.complete = true;
    if (getParameters().isEmpty()) {
        throw new MalformedChallengeException("Authentication challenge is empty");
    }
}

@Override
public Queue<AuthOption> select(
        final Map<String, Header> challenges,
        final HttpHost authhost,
        final HttpResponse response,
        final HttpContext context) throws MalformedChallengeException {
    Args.notNull(challenges, "Map of auth challenges");
    Args.notNull(authhost, "Host");
    Args.notNull(response, "HTTP response");
    Args.notNull(context, "HTTP context");
    final HttpClientContext clientContext = HttpClientContext.adapt(context);

    final Queue<AuthOption> options = new LinkedList<AuthOption>();
    final Lookup<AuthSchemeProvider> registry = clientContext.getAuthSchemeRegistry();
    if (registry == null) {
        this.log.debug("Auth scheme registry not set in the context");
        return options;
    }
    final CredentialsProvider credsProvider = clientContext.getCredentialsProvider();
    if (credsProvider == null) {
        this.log.debug("Credentials provider not set in the context");
        return options;
    }
    final RequestConfig config = clientContext.getRequestConfig();
    Collection<String> authPrefs = getPreferredAuthSchemes(config);
    if (authPrefs == null) {
        authPrefs = DEFAULT_SCHEME_PRIORITY;
    }
    if (this.log.isDebugEnabled()) {
        this.log.debug("Authentication schemes in the order of preference: " + authPrefs);
    }

    for (final String id: authPrefs) {
        final Header challenge = challenges.get(id.toLowerCase(Locale.ROOT));
        if (challenge != null) {
            final AuthSchemeProvider authSchemeProvider = registry.lookup(id);
            if (authSchemeProvider == null) {
                if (this.log.isWarnEnabled()) {
                    this.log.warn("Authentication scheme " + id + " not supported");
                    // Try again
                }
                continue;
            }
            final AuthScheme authScheme = authSchemeProvider.create(context);
            authScheme.processChallenge(challenge);

            final AuthScope authScope = new AuthScope(
                    authhost.getHostName(),
                    authhost.getPort(),
                    authScheme.getRealm(),
                    authScheme.getSchemeName());

            final Credentials credentials = credsProvider.getCredentials(authScope);
            if (credentials != null) {
                options.add(new AuthOption(authScheme, credentials));
            }
        } else {
            if (this.log.isDebugEnabled()) {
                this.log.debug("Challenge for " + id + " authentication scheme not available");
                // Try again
            }
        }
    }
    return options;
}

public Executor authPreemptive(final HttpHost host) {
    final BasicScheme basicScheme = new BasicScheme();
    try {
        basicScheme.processChallenge(new BasicHeader(AUTH.WWW_AUTH, "BASIC "));
    } catch (final MalformedChallengeException ignore) {
    }
    this.authCache.put(host, basicScheme);
    return this;
}

public Executor authPreemptiveProxy(final HttpHost proxy) {
    final BasicScheme basicScheme = new BasicScheme();
    try {
        basicScheme.processChallenge(new BasicHeader(AUTH.PROXY_AUTH, "BASIC "));
    } catch (final MalformedChallengeException ignore) {
    }
    this.authCache.put(proxy, basicScheme);
    return this;
}

@Override
protected void parseChallenge(
        final CharArrayBuffer buffer, final int pos, final int len) throws MalformedChallengeException {
    final HeaderValueParser parser = BasicHeaderValueParserHC4.INSTANCE;
    final ParserCursor cursor = new ParserCursor(pos, buffer.length());
    final HeaderElement[] elements = parser.parseElements(buffer, cursor);
    if (elements.length == 0) {
        throw new MalformedChallengeException("Authentication challenge is empty");
    }
    this.params.clear();
    for (final HeaderElement element : elements) {
        this.params.put(element.getName().toLowerCase(Locale.ENGLISH), element.getValue());
    }
}

@Override
public void processChallenge(final Header header) throws MalformedChallengeException {
    /* We error here because HTTP signature based authentication doesn't
     * work on a challenge response model. Even if we get passed a header there
     * is no response header available for us to process. */

    throw new IllegalStateException("No challenge should ever occur");
}

@Override
public Map<String, Header> getChallenges(final HttpHost authhost,
                                         final HttpResponse response,
                                         final HttpContext context)
        throws MalformedChallengeException {

    /* Unfortunately, we have to abuse the challenge functionality in
     * because it won't enabled authentication unless at least a single
     * challenge is available. The HTTP response for a HTTP Signatures
     * API will never contain a challenge header, so effectively any
     * headers that are added will never match. */

    return this.challenges;
}

private void processChallenge(String headerName, String headerValue) {
    try {
        mDigestScheme.processChallenge(new BasicHeader(headerName, headerValue));
    } catch (MalformedChallengeException e) {
        Timber.e(e, "Error processing header " + headerName + " for DIGEST authentication.");
    }
}

@Override
protected void parseChallenge(
        final CharArrayBuffer buffer, int pos, int len) throws MalformedChallengeException {
    HeaderValueParser parser = BasicHeaderValueParser.DEFAULT;
    ParserCursor cursor = new ParserCursor(pos, buffer.length()); 
    HeaderElement[] elements = parser.parseElements(buffer, cursor);
    if (elements.length == 0) {
        throw new MalformedChallengeException("Authentication challenge is empty");
    }

    this.params = new HashMap<String, String>(elements.length);
    for (HeaderElement element : elements) {
        this.params.put(element.getName(), element.getValue());
    }
}

/**
 * Processes the Digest challenge.
 *  
 * @param header the challenge header
 * 
 * @throws MalformedChallengeException is thrown if the authentication challenge
 * is malformed
 */
@Override
public void processChallenge(
        final Header header) throws MalformedChallengeException {
    super.processChallenge(header);

    if (getParameter("realm") == null) {
        throw new MalformedChallengeException("missing realm in challange");
    }
    if (getParameter("nonce") == null) {
        throw new MalformedChallengeException("missing nonce in challange");   
    }

    boolean unsupportedQop = false;
    // qop parsing
    String qop = getParameter("qop");
    if (qop != null) {
        StringTokenizer tok = new StringTokenizer(qop,",");
        while (tok.hasMoreTokens()) {
            String variant = tok.nextToken().trim();
            if (variant.equals("auth")) {
                qopVariant = QOP_AUTH;
                break; //that's our favourite, because auth-int is unsupported
            } else if (variant.equals("auth-int")) {
                qopVariant = QOP_AUTH_INT;               
            } else {
                unsupportedQop = true;
            }     
        }
    }        

    if (unsupportedQop && (qopVariant == QOP_MISSING)) {
        throw new MalformedChallengeException("None of the qop methods is supported");   
    }
    // Reset cnonce
    this.cnonce = null;
    this.complete = true;
}

public Map<String, Header> getChallenges(
        final HttpResponse response, 
        final HttpContext context) throws MalformedChallengeException {
    if (response == null) {
        throw new IllegalArgumentException("HTTP response may not be null");
    }
    Header[] headers = response.getHeaders(AUTH.WWW_AUTH);
    return parseChallenges(headers);
}

public Map<String, Header> getChallenges(
        final HttpResponse response, 
        final HttpContext context) throws MalformedChallengeException {
    if (response == null) {
        throw new IllegalArgumentException("HTTP response may not be null");
    }
    Header[] headers = response.getHeaders(AUTH.PROXY_AUTH);
    return parseChallenges(headers);
}

@Override
protected void parseChallenge(
        final CharArrayBuffer buffer, final int pos, final int len) throws MalformedChallengeException {
    final HeaderValueParser parser = BasicHeaderValueParserHC4.INSTANCE;
    final ParserCursor cursor = new ParserCursor(pos, buffer.length());
    final HeaderElement[] elements = parser.parseElements(buffer, cursor);
    if (elements.length == 0) {
        throw new MalformedChallengeException("Authentication challenge is empty");
    }
    this.params.clear();
    for (final HeaderElement element : elements) {
        this.params.put(element.getName().toLowerCase(Locale.ENGLISH), element.getValue());
    }
}

/**
 * Handle a challenge from an OAuth server.
 */
@Override
public void processChallenge(Header challenge)
        throws MalformedChallengeException {
    super.processChallenge(challenge);
    complete = true;
}