Add support for DoH

app/src/main/java/com/hippo/ehviewer/Settings.java

@@ -91,7 +91,8 @@ public class Settings {
     public static final String KEY_ENABLE_FINGERPRINT = "enable_fingerprint";
     public static final String KEY_READ_CACHE_SIZE = "read_cache_size";
     public static final int DEFAULT_READ_CACHE_SIZE = 160;
-    public static final String KEY_BUILT_IN_HOSTS = "built_in_hosts";
+    public static final String KEY_BUILT_IN_HOSTS = "built_in_hosts_2";
+    public static final String KEY_DOH = "dns_over_https";
     public static final String KEY_APP_LANGUAGE = "app_language";
     private static final String TAG = Settings.class.getSimpleName();
     private static final String KEY_VERSION_CODE = "version_code";
@@ -235,6 +236,7 @@ public class Settings {
     private static final String KEY_SAVE_CRASH_LOG = "save_crash_log";
     private static final boolean DEFAULT_SAVE_CRASH_LOG = false;
     private static final boolean DEFAULT_BUILT_IN_HOSTS = false;
+    private static final boolean DEFAULT_DOH = false;
     private static final String DEFAULT_APP_LANGUAGE = "system";
     private static final String KEY_PROXY_TYPE = "proxy_type";
     private static final int DEFAULT_PROXY_TYPE = EhProxySelector.TYPE_SYSTEM;
@@ -272,9 +274,9 @@ public class Settings {
 
     private static void fixDefaultValue(Context context) {
         // Enable builtin hosts if the country is CN
-        if (!sSettingsPre.contains(KEY_BUILT_IN_HOSTS)) {
+        if (!sSettingsPre.contains(KEY_DOH)) {
             if ("CN".equals(Locale.getDefault().getCountry())) {
-                putBuiltInHosts(true);
+                putDoH(true);
             }
         }
     }
@@ -1002,6 +1004,14 @@ public class Settings {
         putBoolean(KEY_BUILT_IN_HOSTS, value);
     }
 
+    public static boolean getDoH() {
+        return getBoolean(KEY_DOH, DEFAULT_DOH);
+    }
+
+    public static void putDoH(boolean value) {
+        putBoolean(KEY_DOH, value);
+    }
+
     public static String getAppLanguage() {
         return getString(KEY_APP_LANGUAGE, DEFAULT_APP_LANGUAGE);
     }

app/src/main/java/com/hippo/ehviewer/client/EhDns.java

@@ -37,6 +37,9 @@ import java.util.List;
 import java.util.Map;
 
 import okhttp3.Dns;
+import okhttp3.HttpUrl;
+import okhttp3.OkHttpClient;
+import okhttp3.dnsoverhttps.DnsOverHttps;
 
 public class EhDns implements Dns {
 
@@ -53,9 +56,27 @@ public class EhDns implements Dns {
     }
 
     private final Hosts hosts;
+    private static DnsOverHttps dnsOverHttps;
 
     public EhDns(Context context) {
         hosts = EhApplication.getHosts(context);
+        DnsOverHttps.Builder builder = new DnsOverHttps.Builder()
+                .client(new OkHttpClient.Builder().build())
+                .url(HttpUrl.get("https://cloudflare-dns.com/dns-query"));
+        try {
+            builder.bootstrapDnsHosts(InetAddress.getByName("162.159.36.1"),
+                    InetAddress.getByName("162.159.46.1"),
+                    InetAddress.getByName("1.1.1.1"),
+                    InetAddress.getByName("1.0.0.1"),
+                    InetAddress.getByName("162.159.132.53"),
+                    InetAddress.getByName("2606:4700:4700::1111"),
+                    InetAddress.getByName("2606:4700:4700::1001"),
+                    InetAddress.getByName("2606:4700:4700::0064"),
+                    InetAddress.getByName("2606:4700:4700::6400"));
+        } catch (UnknownHostException e) {
+            e.printStackTrace();
+        }
+        dnsOverHttps = builder.post(true).build();
     }
 
     private static void put(Map<String, InetAddress> map, String host, String ip) {
@@ -79,6 +100,12 @@ public class EhDns implements Dns {
                 return Collections.singletonList(inetAddress);
             }
         }
+        if (Settings.getDoH()) {
+            List<InetAddress> inetAddresses = dnsOverHttps.lookup(hostname);
+            if (inetAddresses != null && inetAddresses.size() > 0) {
+                return inetAddresses;
+            }
+        }
 
         try {
             return Arrays.asList(InetAddress.getAllByName(hostname));