aaa4j-radius 组装radius报文，发送eap中继挑战 java

你可以使用 aaa4j-radius 库来组装 RADIUS 报文并发送 EAP 中继挑战。以下是一个使用该库的示例代码：

import net.jradius.client.RadiusClient;
import net.jradius.dictionary.Attr_UserName;
import net.jradius.dictionary.Attr_UserPassword;
import net.jradius.dictionary.Attr_NASIPAddress;
import net.jradius.dictionary.Attr_NASPort;
import net.jradius.dictionary.Attr_ReplyMessage;
import net.jradius.dictionary.Attr_EAPMessage;
import net.jradius.dictionary.Attr_MessageAuthenticator;
import net.jradius.exception.RadiusException;
import net.jradius.packet.attribute.AttributeList;
import net.jradius.packet.attribute.RadiusAttribute;
import net.jradius.packet.attribute.value.AttributeValueOctets;
import net.jradius.packet.attribute.value.AttributeValueString;
import net.jradius.packet.eap.EAPChallengeRequest;
import net.jradius.packet.eap.EAPCode;
import net.jradius.packet.eap.EAPPacket;
import net.jradius.packet.eap.EAPType;

public class RadiusEAPChallenge {
    public static void main(String[] args) {
        String radiusServerIp = "192.168.0.1";
        String sharedSecret = "sharedSecret";
        String username = "user123";
        String password = "password123";
        String nasIpAddress = "192.168.0.2";
        int nasPort = 1812;

        try {
            RadiusClient client = new RadiusClient(radiusServerIp, sharedSecret);
            client.setAuthProtocol(RadiusClient.AUTH_PAP);

            AttributeList attributeList = new AttributeList();
            attributeList.add(new Attr_UserName(username));
            attributeList.add(new Attr_UserPassword(password));
            attributeList.add(new Attr_NASIPAddress(nasIpAddress));
            attributeList.add(new Attr_NASPort(nasPort));

            EAPPacket eapPacket = new EAPPacket(EAPCode.REQUEST, EAPType.MD5_CHALLENGE, 1);
            eapPacket.setData(new EAPChallengeRequest().getBytes());

            attributeList.add(new Attr_EAPMessage(eapPacket.getBytes()));

            RadiusAttribute messageAuthenticator = new Attr_MessageAuthenticator();
            attributeList.add(messageAuthenticator);

            client.authenticate(attributeList);

            if (client.isAccessAccepted()) {
                System.out.println("Access accepted");
            } else {
                System.out.println("Access rejected");
            }
        } catch (RadiusException e) {
            e.printStackTrace();
        }
    }
}

请注意，你需要将 `radiusServerIp`、`sharedSecret`、`username`、`password`、`nasIpAddress` 和 `nasPort` 替换为你自己的实际值。此代码将创建一个 RADIUS 请求报文，其中包含 EAP 挑战请求，并使用指定的用户名和密码进行身份验证。