Integrate LetsEncryptAdder to fix https downloads in Curse (#757)

* Integrate LetsEncryptAdder to fix https downloads in Curse

* Switch to ISRG roots

* binary for certificates

---------

Co-authored-by: bombcar <github@bombcar.com>

.gitattributes

@@ -42,3 +42,4 @@
 *.[pP][sS]1             text eol=crlf
 
 *[aA][uU][tT][oO][gG][eE][nN][eE][rR][aA][tT][eE][dD]* binary
+*.der binary

src/main/java/com/dreammaster/coremod/DepLoader.java

@@ -148,6 +148,12 @@ public void windowClosing(WindowEvent e) {
             for (Dependency d : deps) if (!d.isDisabled() && !d.isFound()) count++;
             if (count > 0) {
                 LOGGER.info("{} dependencies to download.", count);
+                try {
+                    LetsEncryptAdder.addLetsEncryptCertificates();
+                } catch (Exception e) {
+                    LOGGER.warn(
+                            "Could not ensure Let's Encrypt root certificates are present, downloads might fail on older Java versions.");
+                }
                 downloaded = true;
                 dialog.setJobCount(count);
                 SwingUtilities.invokeLater(() -> dialog.setVisible(true));

src/main/java/com/dreammaster/coremod/LetsEncryptAdder.java

@@ -0,0 +1,145 @@
+package com.dreammaster.coremod;
+
+import java.io.BufferedInputStream;
+import java.io.InputStream;
+import java.net.URL;
+import java.net.URLConnection;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.security.KeyStore;
+import java.security.cert.CertificateFactory;
+import java.util.Objects;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import javax.net.ssl.SSLContext;
+import javax.net.ssl.TrustManagerFactory;
+
+import org.apache.commons.io.IOUtils;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
+/**
+ * Adds the Let's encrypt X3 root SSL certificate to fix HTTPS connection problems. <br>
+ *
+ * Taken from: <a href=
+ * "https://github.com/Cloudhunter/LetsEncryptCraft/blob/master/src/main/java/uk/co/cloudhunter/letsencryptcraft/LetsEncryptAdder.java">LetsEncryptCraft</a>
+ * <br>
+ * Original code license:
+ * 
+ * <pre>
+ * MIT License
+ *
+ * Copyright (c) 2018 Cloudhunter
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ * </pre>
+ */
+public class LetsEncryptAdder {
+
+    private static boolean alreadyAdded = false;
+    private static final Logger LOGGER = LogManager.getLogger(LetsEncryptAdder.class);
+
+    private static void trustLetsEncryptRoots() throws Exception {
+        final InputStream cert1 = Objects.requireNonNull(
+                LetsEncryptAdder.class.getResourceAsStream("/assets/letsencryptroot/isrg-root-x1.der"),
+                "Embedded let's encrypt certificate X1 not found");
+        final InputStream cert2 = Objects.requireNonNull(
+                LetsEncryptAdder.class.getResourceAsStream("/assets/letsencryptroot/isrg-root-x2.der"),
+                "Embedded let's encrypt certificate X2 not found");
+
+        KeyStore keyStore = KeyStore.getInstance(KeyStore.getDefaultType());
+        Path ksPath = Paths.get(System.getProperty("java.home"), "lib", "security", "cacerts");
+        keyStore.load(Files.newInputStream(ksPath), "changeit".toCharArray());
+
+        CertificateFactory cf = CertificateFactory.getInstance("X.509");
+
+        keyStore.setCertificateEntry("isrg-root-x1", cf.generateCertificate(new BufferedInputStream(cert1)));
+        keyStore.setCertificateEntry("isrg-root-x2", cf.generateCertificate(new BufferedInputStream(cert2)));
+
+        TrustManagerFactory tmf = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
+        tmf.init(keyStore);
+        SSLContext sslContext = SSLContext.getInstance("TLS");
+        sslContext.init(null, tmf.getTrustManagers(), null);
+        SSLContext.setDefault(sslContext);
+    }
+
+    public static void addLetsEncryptCertificates() {
+        if (alreadyAdded) {
+            return;
+        }
+
+        String version = System.getProperty("java.version");
+        Pattern p = Pattern.compile("^(\\d+\\.\\d+).*?_(\\d+).*");
+        Matcher matcher = p.matcher(version);
+        String majorVersion;
+        int minorVersion;
+        if (matcher.matches()) {
+            majorVersion = matcher.group(1);
+            minorVersion = Integer.parseInt(matcher.group(2));
+        } else {
+            majorVersion = "1.7";
+            minorVersion = 110;
+            LOGGER.info("Regex to parse Java version failed - applying anyway.");
+        }
+
+        switch (majorVersion) {
+            case "1.7":
+                if (minorVersion >= 111) {
+                    LOGGER.info("Not running as Java version is at least Java 7u111.");
+                    alreadyAdded = true;
+                    return;
+                }
+                break;
+            case "1.8":
+                if (minorVersion >= 101) {
+                    LOGGER.info("Not running as Java version is at least Java 8u101.");
+                    alreadyAdded = true;
+                    return;
+                }
+                break;
+        }
+
+        String body = "";
+        try {
+            LOGGER.info("Adding Let's Encrypt certificate...");
+            LetsEncryptAdder.trustLetsEncryptRoots();
+            LOGGER.info("Done, attempting to connect to https://helloworld.letsencrypt.org...");
+            URL url = new URL("https://helloworld.letsencrypt.org");
+            URLConnection conn = url.openConnection();
+            conn.setConnectTimeout(5000);
+            conn.setReadTimeout(5000);
+            InputStream inputStream = conn.getInputStream();
+            body = IOUtils.toString(inputStream);
+        } catch (Exception e) {
+            LOGGER.error(
+                    "An error occurred whilst adding the Let's Encrypt root certificate. I'm afraid you wont be able to access resources with a Let's Encrypt certificate D:",
+                    e);
+        }
+
+        if (body.isEmpty()) {
+            LOGGER.error(
+                    "An unknown error occurred whilst adding the Let's Encrypt root certificate. I'm afraid you may not be able to access resources with a Let's Encrypt certificate D:");
+        } else {
+            LOGGER.info("Done - you are now able to access resources with a Let's Encrypt certificate :D");
+        }
+        alreadyAdded = true;
+    }
+}