HostFilter.java

package com.hwlcn.security.web.filter.authz;

import com.hwlcn.security.util.StringUtils;

import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import java.util.Map;
import java.util.regex.Pattern;

public class HostFilter extends AuthorizationFilter {

    public static final String IPV4_QUAD_REGEX = "(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2(?:[0-4][0-9]|5[0-5]))";

    public static final String IPV4_REGEX = "(?:" + IPV4_QUAD_REGEX + "\\.){3}" + IPV4_QUAD_REGEX + "$";
    public static final Pattern IPV4_PATTERN = Pattern.compile(IPV4_REGEX);

    public static final String PRIVATE_CLASS_B_SUBSET = "(?:1[6-9]|2[0-9]|3[0-1])";

    public static final String PRIVATE_CLASS_A_REGEX = "10\\.(?:" + IPV4_QUAD_REGEX + "\\.){2}" + IPV4_QUAD_REGEX + "$";

    public static final String PRIVATE_CLASS_B_REGEX =
            "172\\." + PRIVATE_CLASS_B_SUBSET + "\\." + IPV4_QUAD_REGEX + "\\." + IPV4_QUAD_REGEX + "$";

    public static final String PRIVATE_CLASS_C_REGEX = "192\\.168\\." + IPV4_QUAD_REGEX + "\\." + IPV4_QUAD_REGEX + "$";

    Map<String, String> authorizedIps;
    Map<String, String> deniedIps;
    Map<String, String> authorizedHostnames;
    Map<String, String> deniedHostnames;


    public void setAuthorizedHosts(String authorizedHosts) {
        if (!StringUtils.hasText(authorizedHosts)) {
            throw new IllegalArgumentException("authorizedHosts argument cannot be null or empty.");
        }
        String[] hosts = StringUtils.tokenizeToStringArray(authorizedHosts, ", \t");

        for (String host : hosts) {
            String periodsReplaced = host.replace(".", "\\.");

            String wildcardsReplaced = periodsReplaced.replace("*", IPV4_QUAD_REGEX);

            if (IPV4_PATTERN.matcher(wildcardsReplaced).matches()) {
                authorizedIps.put(host, wildcardsReplaced);
            } else {

            }
        }

    }

    public void setDeniedHosts(String deniedHosts) {
        if (!StringUtils.hasText(deniedHosts)) {
            throw new IllegalArgumentException("deniedHosts argument cannot be null or empty.");
        }

    }

    protected boolean isIpv4Candidate(String host) {
        String[] quads = StringUtils.tokenizeToStringArray(host, ".");
        if (quads == null || quads.length != 4) {
            return false;
        }
        for (String quad : quads) {
            if (!quad.equals("*")) {
                try {
                    Integer.parseInt(quad);
                } catch (NumberFormatException nfe) {
                    return false;
                }
            }
        }
        return true;
    }

    protected boolean isAccessAllowed(ServletRequest request, ServletResponse response, Object mappedValue) throws Exception {
        throw new UnsupportedOperationException("Not yet fully implemented!!!");
    }
}