Refactoring

app/src/main/java/eu/faircode/email/ActivityDMARC.java

@@ -565,7 +565,7 @@ public class ActivityDMARC extends ActivityBase {
             }
 
             try {
-                InetAddress addr = InetAddress.getByName(text);
+                InetAddress addr = DnsHelper.getByName(context, text);
                 IPInfo info = IPInfo.getOrganization(addr, context);
                 ssb.append('(').append(info.org).append(") ");
             } catch (Throwable ex) {

app/src/main/java/eu/faircode/email/DnsBlockList.java

@@ -205,7 +205,7 @@ public class DnsBlockList {
         for (BlockList blocklist : blocklists)
             if (isEnabled(context, blocklist) &&
                     blocklist.numeric == numeric &&
-                    isJunk(host, blocklist)) {
+                    isJunk(context, host, blocklist)) {
                 blocked = true;
                 break;
             }
@@ -217,11 +217,11 @@ public class DnsBlockList {
         return blocked;
     }
 
-    private static boolean isJunk(String host, BlockList blocklist) {
+    private static boolean isJunk(Context context, String host, BlockList blocklist) {
         try {
             if (blocklist.numeric) {
                 long start = new Date().getTime();
-                InetAddress[] addresses = InetAddress.getAllByName(host);
+                InetAddress[] addresses = DnsHelper.getAllByName(context, host);
                 long elapsed = new Date().getTime() - start;
                 Log.i("isJunk resolved=" + host + " elapse=" + elapsed + " ms");
                 for (InetAddress addr : addresses) {
@@ -249,7 +249,7 @@ public class DnsBlockList {
 
                         lookup.append(blocklist.address);
 
-                        if (isJunk(lookup.toString(), blocklist.responses))
+                        if (isJunk(context, lookup.toString(), blocklist.responses))
                             return true;
                     } catch (Throwable ex) {
                         Log.w(ex);
@@ -258,7 +258,7 @@ public class DnsBlockList {
             } else {
                 long start = new Date().getTime();
                 String lookup = host + "." + blocklist.address;
-                boolean junk = isJunk(lookup, blocklist.responses);
+                boolean junk = isJunk(context, lookup, blocklist.responses);
                 long elapsed = new Date().getTime() - start;
                 Log.i("isJunk" + " " + lookup + "=" + junk + " elapsed=" + elapsed);
                 return junk;
@@ -270,12 +270,12 @@ public class DnsBlockList {
         return false;
     }
 
-    private static boolean isJunk(String lookup, InetAddress[] responses) {
+    private static boolean isJunk(Context context, String lookup, InetAddress[] responses) {
         long start = new Date().getTime();
         InetAddress result;
         try {
             // Possibly blocked
-            result = InetAddress.getByName(lookup);
+            result = DnsHelper.getByName(context, lookup);
         } catch (UnknownHostException ignored) {
             // Not blocked
             result = null;

app/src/main/java/eu/faircode/email/DnsHelper.java

@@ -351,6 +351,14 @@ public class DnsHelper {
         return result;
     }
 
+    static InetAddress getByName(Context context, String host) throws UnknownHostException {
+        return InetAddress.getByName(host);
+    }
+
+    static InetAddress[] getAllByName(Context context, String host) throws UnknownHostException {
+        return InetAddress.getAllByName(host);
+    }
+
     static void verifyDane(X509Certificate[] chain, String server, int port) throws CertificateException {
         Handler handler = new Handler() {
             @Override

app/src/main/java/eu/faircode/email/EmailProvider.java

@@ -436,7 +436,7 @@ public class EmailProvider implements Parcelable {
 
         if (false) // Unsafe: the password could be sent to an unrelated email server
             try {
-                InetAddress iaddr = InetAddress.getByName(domain.toLowerCase(Locale.ROOT));
+                InetAddress iaddr = DnsHelper.getByName(context, domain.toLowerCase(Locale.ROOT));
                 List<String> commonNames =
                         ConnectionHelper.getCommonNames(context, domain.toLowerCase(Locale.ROOT), 443, SCAN_TIMEOUT);
                 EntityLog.log(context, "Website common names=" + TextUtils.join(",", commonNames));
@@ -450,7 +450,7 @@ public class EmailProvider implements Parcelable {
 
                     if (!altName.equalsIgnoreCase(domain))
                         try {
-                            InetAddress ialt = InetAddress.getByName(altName);
+                            InetAddress ialt = DnsHelper.getByName(context, altName);
                             if (!ialt.equals(iaddr)) {
                                 EntityLog.log(context, "Using website common name=" + altName);
                                 candidates.addAll(_fromDomain(context, altName.toLowerCase(Locale.ROOT), email, discover, intf));
@@ -509,7 +509,7 @@ public class EmailProvider implements Parcelable {
             for (DnsHelper.DnsRecord record : records)
                 try {
                     String target = record.response.toLowerCase(Locale.ROOT);
-                    InetAddress.getByName(target);
+                    DnsHelper.getByName(context, target);
 
                     EmailProvider mx1 = new EmailProvider(domain);
                     mx1.imap.score = 0;
@@ -1340,7 +1340,7 @@ public class EmailProvider implements Parcelable {
                 @Override
                 public Boolean call() {
                     try {
-                        for (InetAddress iaddr : InetAddress.getAllByName(host)) {
+                        for (InetAddress iaddr : DnsHelper.getAllByName(context, host)) {
                             InetSocketAddress address = new InetSocketAddress(iaddr, Server.this.port);
 
                             SocketFactory factory = (starttls
@@ -1380,7 +1380,7 @@ public class EmailProvider implements Parcelable {
                                                     String similar = name;
                                                     if (similar.startsWith("*."))
                                                         similar = similar.substring(2);
-                                                    InetAddress isimilar = InetAddress.getByName(similar);
+                                                    InetAddress isimilar = DnsHelper.getByName(context, similar);
                                                     if (iaddr.equals(isimilar)) {
                                                         score += 1;
                                                         EntityLog.log(context, "Similar " + similar + " host=" + host);

app/src/main/java/eu/faircode/email/EmailService.java

@@ -623,7 +623,7 @@ public class EmailService implements AutoCloseable {
 
             String key = "dns." + host;
             try {
-                main = InetAddress.getByName(host);
+                main = DnsHelper.getByName(context, host);
                 EntityLog.log(context, EntityLog.Type.Network, "Main address=" + main);
                 prefs.edit().putString(key, main.getHostAddress()).apply();
             } catch (UnknownHostException ex) {
@@ -632,7 +632,7 @@ public class EmailService implements AutoCloseable {
                     throw ex;
                 else {
                     EntityLog.log(context, EntityLog.Type.Network, "Using " + key + "=" + last);
-                    main = InetAddress.getByName(last);
+                    main = DnsHelper.getByName(context, last);
                 }
             }
 
@@ -641,7 +641,7 @@ public class EmailService implements AutoCloseable {
                 boolean[] has46 = ConnectionHelper.has46(context);
                 if (has46[0])
                     try {
-                        for (InetAddress iaddr : InetAddress.getAllByName(host))
+                        for (InetAddress iaddr : DnsHelper.getAllByName(context, host))
                             if (iaddr instanceof Inet4Address) {
                                 main = iaddr;
                                 EntityLog.log(context, EntityLog.Type.Network, "Preferring=" + main);
@@ -729,7 +729,7 @@ public class EmailService implements AutoCloseable {
                         ex + "\n" + android.util.Log.getStackTraceString(ex));
                 try {
                     // Some devices resolve IPv6 addresses while not having IPv6 connectivity
-                    InetAddress[] iaddrs = InetAddress.getAllByName(host);
+                    InetAddress[] iaddrs = DnsHelper.getAllByName(context, host);
                     int ip4 = (main instanceof Inet4Address ? 1 : 0);
                     int ip6 = (main instanceof Inet6Address ? 1 : 0);
 

app/src/main/java/eu/faircode/email/IPInfo.java

@@ -61,7 +61,7 @@ public class IPInfo {
             Log.i(ex);
         }
 
-        InetAddress address = InetAddress.getByName(host);
+        InetAddress address = DnsHelper.getByName(context, host);
         return new Pair<>(address, getOrganization(address, context));
     }
 

app/src/main/java/eu/faircode/email/SSLHelper.java

@@ -137,7 +137,7 @@ public class SSLHelper {
                         // Fallback: check server/certificate IP address
                         if (!cert_strict)
                             try {
-                                InetAddress ip = InetAddress.getByName(server);
+                                InetAddress ip = DnsHelper.getByName(context, server);
                                 Log.i("Checking server ip=" + ip);
                                 for (String name : names) {
                                     if (name.startsWith("*."))
@@ -145,7 +145,7 @@ public class SSLHelper {
                                     Log.i("Checking cert name=" + name);
 
                                     try {
-                                        for (InetAddress addr : InetAddress.getAllByName(name))
+                                        for (InetAddress addr : DnsHelper.getAllByName(context, name))
                                             if (Arrays.equals(ip.getAddress(), addr.getAddress())) {
                                                 Log.i("Accepted " + name + " for " + server);
                                                 return;