ProductKeyChain.java

/*
 * ProductPublicKey
 */
package gov.usgs.earthquake.distribution;

import gov.usgs.earthquake.product.ProductId;
import gov.usgs.util.Config;
import gov.usgs.util.StringUtils;

import java.security.PublicKey;

import java.util.Iterator;
import java.util.List;
import java.util.LinkedList;
import java.util.logging.Logger;

/**
 * A group of keys that can be used to verify product signatures.
 */
public class ProductKeyChain {

    /** Logging object. */
    private static final Logger LOGGER = Logger.getLogger(ProductKeyChain.class
            .getName());

    /** List of candidate keys. */
    private List<ProductKey> keychain = new LinkedList<ProductKey>();

    /** Empty constructor */
    public ProductKeyChain() {
    }

    /**
     * Constructor for a string of keys
     * @param keys String of keys, separated by commas
     * @param config Config file
     * @throws Exception if error occurs
     */
    public ProductKeyChain(final String keys, final Config config)
            throws Exception {
        this(StringUtils.split(keys, ","), config);
    }

    /**
     * Constructor for list of keys
     * @param keys String list of keys
     * @param config Config file
     * @throws Exception if error occurs
     */
    public ProductKeyChain(final List<String> keys, final Config config)
            throws Exception {
        Iterator<String> iter = keys.iterator();
        while (iter.hasNext()) {
            String keyName = iter.next();
            LOGGER.config("Loading key '" + keyName + "'");
            ProductKey key = (ProductKey) Config.getConfig().getObject(keyName);
            if (key != null) {
                keychain.add(key);
            }
        }
    }

    /**
     * @return the keys
     */
    public List<ProductKey> getKeychain() {
        return keychain;
    }

    /**
     * Find public keys based on configured Keys.
     *
     * @param id ID of product
     * @return an array of candidate keys used to verify a signature.
     */
    public PublicKey[] getProductKeys(final ProductId id) {
        LinkedList<PublicKey> publicKeys = new LinkedList<PublicKey>();
        Iterator<ProductKey> iter = keychain.iterator();
        while (iter.hasNext()) {
            ProductKey key = iter.next();
            if (key.isForProduct(id)) {
                publicKeys.add(key.getKey());
            }
        }
        return publicKeys.toArray(new PublicKey[0]);
    }

}