Apachesshpublickey实现在ssh-core0.14.0中

Apache ssh public key是Apache项目中的一个插件，它可以让用户使用公钥文件进行身份验证，而不需要输入密码。而在ssh-core 0.14.0中，该插件的实现遇到问题，可能导致用户无法成功进行身份验证。以下是一个改进版的代码示例，可以解决这个问题：

import org.apache.sshd.common.config.keys.AuthorizedKeysAuthenticator;
import org.apache.sshd.common.config.keys.AuthorizedKeysAuthenticatorWrapper;
import org.apache.sshd.common.config.keys.AuthorizedKeysObserver;
import org.apache.sshd.common.config.keys.KeyUtils;
import org.apache.sshd.common.session.Session;

public class MyAuthorizedKeysAuthenticator extends AuthorizedKeysAuthenticatorWrapper {

    public MyAuthorizedKeysAuthenticator() {
        super(new AuthorizedKeysAuthenticator());
    }

    @Override
    public void addAuthorizedKeysObserver(AuthorizedKeysObserver observer) {
        super.addAuthorizedKeysObserver(observer);
    }

    @Override
    public boolean authenticate(Session session, String username, byte[] password) {
        byte[] allowed = super.getAuthorizedKeys(username);
        if (allowed == null) {
            return false;
        }

        String alg = null;
        String digest = null;
        int pos = 0;
        for (;;) {
            pos = KeyUtils.scanPreferredPublicKey(allowed, pos, allowed.length);
            if (pos >= allowed.length) {
                break;
            }
            int markerIndex = KeyUtils.indexOf(allowed, KeyUtils.EMPTY_BYTE_ARRAY, pos);
            if (markerIndex < 0) {
                break;
            }

            String keyType = new String(allowed, pos, markerIndex - pos);
            boolean ok = false;
            if ("ssh-rsa".equals(keyType)) {
                alg = "RSA";
                digest = "SHA-1";
                ok = true;
            } else if ("ssh-dss".equals(keyType)) {
                alg = "DSA";
                digest = "SHA-1";
                ok = true;
            }

            if (ok) {
                try {
                    if (super.authenticate(session, username, allowed, pos, alg, digest)) {
                        return