org.springframework.security.oauth2.provider.authentication.BearerTokenExtractor.java Source code

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Here is the source code for org.springframework.security.oauth2.provider.authentication.BearerTokenExtractor.java

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/*
 * Copyright 2013-2014 the original author or authors.
 *
 * Licensed 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.springframework.security.oauth2.provider.authentication;

import java.util.Enumeration;

import javax.servlet.http.HttpServletRequest;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.security.core.Authentication;
import org.springframework.security.oauth2.common.OAuth2AccessToken;
import org.springframework.security.web.authentication.preauth.PreAuthenticatedAuthenticationToken;

/**
 * {@link TokenExtractor} that strips the authenticator from a bearer token request (with an Authorization header in the
 * form "Bearer <code><TOKEN></code>", or as a request parameter if that fails). The access token is the principal in
 * the authentication token that is extracted.
 * 
 * @author Dave Syer
 * 
 */
public class BearerTokenExtractor implements TokenExtractor {

    private final static Log logger = LogFactory.getLog(BearerTokenExtractor.class);

    @Override
    public Authentication extract(HttpServletRequest request) {
        String tokenValue = extractToken(request);
        if (tokenValue != null) {
            PreAuthenticatedAuthenticationToken authentication = new PreAuthenticatedAuthenticationToken(tokenValue,
                    "");
            return authentication;
        }
        return null;
    }

    protected String extractToken(HttpServletRequest request) {
        // first check the header...
        String token = extractHeaderToken(request);

        // bearer type allows a request parameter as well
        if (token == null) {
            logger.debug("Token not found in headers. Trying request parameters.");
            token = request.getParameter(OAuth2AccessToken.ACCESS_TOKEN);
            if (token == null) {
                logger.debug("Token not found in request parameters.  Not an OAuth2 request.");
            }
        }

        return token;
    }

    /**
     * Extract the OAuth bearer token from a header.
     * 
     * @param request The request.
     * @return The token, or null if no OAuth authorization header was supplied.
     */
    protected String extractHeaderToken(HttpServletRequest request) {
        Enumeration<String> headers = request.getHeaders("Authorization");
        while (headers.hasMoreElements()) { // typically there is only one (most servers enforce that)
            String value = headers.nextElement();
            if ((value.toLowerCase().startsWith(OAuth2AccessToken.BEARER_TYPE.toLowerCase()))) {
                String authHeaderValue = value.substring(OAuth2AccessToken.BEARER_TYPE.length()).trim();
                int commaIndex = authHeaderValue.indexOf(',');
                if (commaIndex > 0) {
                    authHeaderValue = authHeaderValue.substring(0, commaIndex);
                }
                return authHeaderValue;
            }
        }

        return null;
    }

}