PushCertificate.java

/*
 * Copyright (C) 2015, Google Inc. and others
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Distribution License v. 1.0 which is available at
 * https://www.eclipse.org/org/documents/edl-v10.php.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

package org.eclipse.jgit.transport;

import static org.eclipse.jgit.transport.PushCertificateParser.NONCE;
import static org.eclipse.jgit.transport.PushCertificateParser.PUSHEE;
import static org.eclipse.jgit.transport.PushCertificateParser.PUSHER;
import static org.eclipse.jgit.transport.PushCertificateParser.VERSION;

import java.text.MessageFormat;
import java.util.List;
import java.util.Objects;

import org.eclipse.jgit.internal.JGitText;

/**
 * The required information to verify the push.
 * <p>
 * A valid certificate will not return null from any getter methods; callers may
 * assume that any null value indicates a missing or invalid certificate.
 *
 * @since 4.0
 */
public class PushCertificate {
    /** Verification result of the nonce returned during push. */
    public enum NonceStatus {
        /** Nonce was not expected, yet client sent one anyway. */
        UNSOLICITED,
        /** Nonce is invalid and did not match server's expectations. */
        BAD,
        /** Nonce is required, but was not sent by client. */
        MISSING,
        /**
         * Received nonce matches sent nonce, or is valid within the accepted slop
         * window.
         */
        OK,
        /** Received nonce is valid, but outside the accepted slop window. */
        SLOP
    }

    private final String version;
    private final PushCertificateIdent pusher;
    private final String pushee;
    private final String nonce;
    private final NonceStatus nonceStatus;
    private final List<ReceiveCommand> commands;
    private final String signature;

    PushCertificate(String version, PushCertificateIdent pusher, String pushee,
            String nonce, NonceStatus nonceStatus, List<ReceiveCommand> commands,
            String signature) {
        if (version == null || version.isEmpty()) {
            throw new IllegalArgumentException(MessageFormat.format(
                    JGitText.get().pushCertificateInvalidField, VERSION));
        }
        if (pusher == null) {
            throw new IllegalArgumentException(MessageFormat.format(
                    JGitText.get().pushCertificateInvalidField, PUSHER));
        }
        if (nonce == null || nonce.isEmpty()) {
            throw new IllegalArgumentException(MessageFormat.format(
                    JGitText.get().pushCertificateInvalidField, NONCE));
        }
        if (nonceStatus == null) {
            throw new IllegalArgumentException(MessageFormat.format(
                    JGitText.get().pushCertificateInvalidField,
                    "nonce status")); //$NON-NLS-1$
        }
        if (commands == null || commands.isEmpty()) {
            throw new IllegalArgumentException(MessageFormat.format(
                    JGitText.get().pushCertificateInvalidField,
                    "command")); //$NON-NLS-1$
        }
        if (signature == null || signature.isEmpty()) {
            throw new IllegalArgumentException(
                    JGitText.get().pushCertificateInvalidSignature);
        }
        if (!signature.startsWith(PushCertificateParser.BEGIN_SIGNATURE)
                || !signature.endsWith(PushCertificateParser.END_SIGNATURE + '\n')) {
            throw new IllegalArgumentException(
                    JGitText.get().pushCertificateInvalidSignature);
        }
        this.version = version;
        this.pusher = pusher;
        this.pushee = pushee;
        this.nonce = nonce;
        this.nonceStatus = nonceStatus;
        this.commands = commands;
        this.signature = signature;
    }

    /**
     * Get the certificate version string.
     *
     * @return the certificate version string.
     * @since 4.1
     */
    public String getVersion() {
        return version;
    }

    /**
     * Get the raw line that signed the cert, as a string.
     *
     * @return the raw line that signed the cert, as a string.
     * @since 4.0
     */
    public String getPusher() {
        return pusher.getRaw();
    }

    /**
     * Get identity of the pusher who signed the cert.
     *
     * @return identity of the pusher who signed the cert.
     * @since 4.1
     */
    public PushCertificateIdent getPusherIdent() {
        return pusher;
    }

    /**
     * Get URL of the repository the push was originally sent to.
     *
     * @return URL of the repository the push was originally sent to.
     * @since 4.0
     */
    public String getPushee() {
        return pushee;
    }

    /**
     * Get the raw nonce value that was presented by the pusher.
     *
     * @return the raw nonce value that was presented by the pusher.
     * @since 4.1
     */
    public String getNonce() {
        return nonce;
    }

    /**
     * Get verification status of the nonce embedded in the certificate.
     *
     * @return verification status of the nonce embedded in the certificate.
     * @since 4.0
     */
    public NonceStatus getNonceStatus() {
        return nonceStatus;
    }

    /**
     * Get the list of commands as one string to be feed into the signature
     * verifier.
     *
     * @return the list of commands as one string to be feed into the signature
     *         verifier.
     * @since 4.1
     */
    public List<ReceiveCommand> getCommands() {
        return commands;
    }

    /**
     * Get the raw signature
     *
     * @return the raw signature, consisting of the lines received between the
     *         lines {@code "----BEGIN GPG SIGNATURE-----\n"} and
     *         {@code "----END GPG SIGNATURE-----\n}", inclusive.
     * @since 4.0
     */
    public String getSignature() {
        return signature;
    }

    /**
     * Get text payload of the certificate for the signature verifier.
     *
     * @return text payload of the certificate for the signature verifier.
     * @since 4.1
     */
    public String toText() {
        return toStringBuilder().toString();
    }

    /**
     * Get original text payload plus signature
     *
     * @return original text payload plus signature; the final output will be
     *         valid as input to
     *         {@link org.eclipse.jgit.transport.PushCertificateParser#fromString(String)}.
     * @since 4.1
     */
    public String toTextWithSignature() {
        return toStringBuilder().append(signature).toString();
    }

    private StringBuilder toStringBuilder() {
        StringBuilder sb = new StringBuilder()
                .append(VERSION).append(' ').append(version).append('\n')
                .append(PUSHER).append(' ').append(getPusher())
                .append('\n');
        if (pushee != null) {
            sb.append(PUSHEE).append(' ').append(pushee).append('\n');
        }
        sb.append(NONCE).append(' ').append(nonce).append('\n')
                .append('\n');
        for (ReceiveCommand cmd : commands) {
            sb.append(cmd.getOldId().name())
                .append(' ').append(cmd.getNewId().name())
                .append(' ').append(cmd.getRefName()).append('\n');
        }
        return sb;
    }

    /** {@inheritDoc} */
    @Override
    public int hashCode() {
        return signature.hashCode();
    }

    /** {@inheritDoc} */
    @Override
    public boolean equals(Object o) {
        if (!(o instanceof PushCertificate)) {
            return false;
        }
        PushCertificate p = (PushCertificate) o;
        return version.equals(p.version)
                && pusher.equals(p.pusher)
                && Objects.equals(pushee, p.pushee)
                && nonceStatus == p.nonceStatus
                && signature.equals(p.signature)
                && commandsEqual(this, p);
    }

    private static boolean commandsEqual(PushCertificate c1, PushCertificate c2) {
        if (c1.commands.size() != c2.commands.size()) {
            return false;
        }
        for (int i = 0; i < c1.commands.size(); i++) {
            ReceiveCommand cmd1 = c1.commands.get(i);
            ReceiveCommand cmd2 = c2.commands.get(i);
            if (!cmd1.getOldId().equals(cmd2.getOldId())
                    || !cmd1.getNewId().equals(cmd2.getNewId())
                    || !cmd1.getRefName().equals(cmd2.getRefName())) {
                return false;
            }
        }
        return true;
    }

    /** {@inheritDoc} */
    @Override
    public String toString() {
        return getClass().getSimpleName() + '['
                 + toTextWithSignature() + ']';
    }
}