From f2502b181e6a454c9179a5d71cfc0a2c0ef1d4db Mon Sep 17 00:00:00 2001
From: M66B <M66B@users.noreply.github.com>
Date: Fri, 21 Jun 2024 16:19:29 +0200
Subject: [PATCH] Removed app DNS cache

---
 .../main/java/eu/faircode/email/DnsHelper.java |  9 ---------
 .../java/eu/faircode/email/EmailService.java   | 18 ++----------------
 .../email/FragmentOptionsConnection.java       |  1 -
 3 files changed, 2 insertions(+), 26 deletions(-)

diff --git a/app/src/main/java/eu/faircode/email/DnsHelper.java b/app/src/main/java/eu/faircode/email/DnsHelper.java
index 0aafa8d861..abba732508 100644
--- a/app/src/main/java/eu/faircode/email/DnsHelper.java
+++ b/app/src/main/java/eu/faircode/email/DnsHelper.java
@@ -465,15 +465,6 @@ public class DnsHelper {
         return result;
     }
 
-    static void clear(Context context) {
-        SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
-        SharedPreferences.Editor editor = prefs.edit();
-        for (String key : prefs.getAll().keySet())
-            if (key != null && key.startsWith("dns."))
-                editor.remove(key);
-        editor.apply();
-    }
-
     static boolean hasDnsSec() {
         if (BuildConfig.PLAY_STORE_RELEASE)
             return false;
diff --git a/app/src/main/java/eu/faircode/email/EmailService.java b/app/src/main/java/eu/faircode/email/EmailService.java
index aeb1f3025f..c2c2bc8775 100644
--- a/app/src/main/java/eu/faircode/email/EmailService.java
+++ b/app/src/main/java/eu/faircode/email/EmailService.java
@@ -425,8 +425,6 @@ public class EmailService implements AutoCloseable {
             String certificate, String fingerprint) throws MessagingException {
         properties.put("fairemail.server", host);
 
-        DnsHelper.clear(context);
-
         SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
         boolean bind_socket = prefs.getBoolean("bind_socket", false);
         if (bind_socket &&
@@ -639,20 +637,8 @@ public class EmailService implements AutoCloseable {
             //    throw new MailConnectException(
             //            new SocketConnectException("Debug", new IOException("Test"), host, port, 0));
 
-            String key = "dns." + host;
-            try {
-                main = DnsHelper.getByName(context, host, dnssec);
-                EntityLog.log(context, EntityLog.Type.Network, "Main address=" + main);
-                prefs.edit().putString(key, main.getHostAddress()).apply();
-            } catch (UnknownHostException ex) {
-                String last = prefs.getString(key, null);
-                if (TextUtils.isEmpty(last))
-                    throw ex;
-                else {
-                    EntityLog.log(context, EntityLog.Type.Network, "Using " + key + "=" + last);
-                    main = DnsHelper.getByName(context, last, dnssec);
-                }
-            }
+            main = DnsHelper.getByName(context, host, dnssec);
+            EntityLog.log(context, EntityLog.Type.Network, "Main address=" + main);
 
             boolean prefer_ip4 = prefs.getBoolean("prefer_ip4", true);
             if (prefer_ip4 && main instanceof Inet6Address) {
diff --git a/app/src/main/java/eu/faircode/email/FragmentOptionsConnection.java b/app/src/main/java/eu/faircode/email/FragmentOptionsConnection.java
index 8b70c77e3e..30176c583f 100644
--- a/app/src/main/java/eu/faircode/email/FragmentOptionsConnection.java
+++ b/app/src/main/java/eu/faircode/email/FragmentOptionsConnection.java
@@ -352,7 +352,6 @@ public class FragmentOptionsConnection extends FragmentBase implements SharedPre
         swDnsCustom.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
             @Override
             public void onCheckedChanged(CompoundButton buttonView, boolean checked) {
-                DnsHelper.clear(buttonView.getContext());
                 prefs.edit().putBoolean("dns_custom", checked).apply();
                 tvDnsExtra.setEnabled(checked || Build.VERSION.SDK_INT < Build.VERSION_CODES.Q);
                 etDnsExtra.setEnabled(checked || Build.VERSION.SDK_INT < Build.VERSION_CODES.Q);