diff options
| -rw-r--r-- | app/src/main/java/se/leap/bitmaskclient/providersetup/connectivity/DnsResolver.java | 127 |
1 files changed, 67 insertions, 60 deletions
diff --git a/app/src/main/java/se/leap/bitmaskclient/providersetup/connectivity/DnsResolver.java b/app/src/main/java/se/leap/bitmaskclient/providersetup/connectivity/DnsResolver.java index b50c480d..c6cc5305 100644 --- a/app/src/main/java/se/leap/bitmaskclient/providersetup/connectivity/DnsResolver.java +++ b/app/src/main/java/se/leap/bitmaskclient/providersetup/connectivity/DnsResolver.java @@ -1,84 +1,85 @@ - package se.leap.bitmaskclient.providersetup.connectivity; +package se.leap.bitmaskclient.providersetup.connectivity; - import static java.net.InetAddress.getByName; +import static java.net.InetAddress.getByName; - import android.util.Log; +import android.util.Log; - import androidx.annotation.NonNull; +import androidx.annotation.NonNull; - import java.net.InetAddress; - import java.net.UnknownHostException; - import java.util.ArrayList; - import java.util.List; +import java.net.InetAddress; +import java.net.UnknownHostException; +import java.util.ArrayList; +import java.util.List; - import de.blinkt.openvpn.core.VpnStatus; - import okhttp3.Dns; - import okhttp3.HttpUrl; - import okhttp3.OkHttpClient; - import okhttp3.dnsoverhttps.DnsOverHttps; - import se.leap.bitmaskclient.base.models.Provider; - import se.leap.bitmaskclient.base.models.ProviderObservable; - import se.leap.bitmaskclient.base.utils.IPAddress; +import de.blinkt.openvpn.core.VpnStatus; +import okhttp3.Dns; +import okhttp3.HttpUrl; +import okhttp3.OkHttpClient; +import okhttp3.dnsoverhttps.DnsOverHttps; +import se.leap.bitmaskclient.base.models.Provider; +import se.leap.bitmaskclient.base.models.ProviderObservable; +import se.leap.bitmaskclient.base.utils.IPAddress; class DnsResolver implements Dns { OkHttpClient dohHttpClient; - boolean forceDoH; + boolean preferDoH; - public DnsResolver(OkHttpClient dohHttpClient, boolean forceDoH) { + public DnsResolver(OkHttpClient dohHttpClient, boolean preferDoH) { this.dohHttpClient = dohHttpClient; - this.forceDoH = forceDoH; + this.preferDoH = preferDoH; } @NonNull @Override public List<InetAddress> lookup(@NonNull String hostname) throws UnknownHostException { Log.d("DNS", "trying to resolve DNS for " + hostname); + List<InetAddress> list = null; + if (preferDoH) { + if ((list = tryLookupDoH(hostname)) == null) { + list = tryLookupSystemDNS(hostname); + } + } else { + if ((list = tryLookupSystemDNS(hostname)) == null) { + list = tryLookupDoH(hostname); + } + } + + if (list != null) { + return list; + } + Log.d("DNS", "try hard coded IPs"); + // let's check if there's an hard-coded IP we can use + ProviderObservable observable = ProviderObservable.getInstance(); + Provider currentProvider; + if (observable.getProviderForDns() != null) { + currentProvider = observable.getProviderForDns(); + } else { + currentProvider = observable.getCurrentProvider(); + } + String ip = currentProvider.getIpForHostname(hostname); + if (!ip.isEmpty()) { + VpnStatus.logWarning("[API] Normal DNS resolution for " + hostname + " seems to be blocked. Circumventing."); + ArrayList<InetAddress> addresses = new ArrayList<>(); + addresses.add(InetAddress.getByAddress(hostname, IPAddress.asBytes(ip))); + return addresses; + } else { + VpnStatus.logWarning("[API] Could not resolve DNS for " + hostname); + throw new UnknownHostException("Hostname " + hostname + " not found"); + } + } + + private List<InetAddress> tryLookupSystemDNS(@NonNull String hostname) throws RuntimeException, UnknownHostException { try { - if (forceDoH) { - List<InetAddress> list = lookupDoH(hostname); - for (InetAddress address : list) { - Log.d("DNS", "DoH ---> " + address.toString()); - } - return list; - } + Log.d("DNS", "trying to resolve " + hostname + "with system DNS"); return Dns.SYSTEM.lookup(hostname); } catch (UnknownHostException e) { e.printStackTrace(); - Log.e("DNS", "DoH via cloudflare failed"); - - // if not yet tried, do DNS over Https after normal DNS failed - if (!forceDoH) { - try { - return lookupDoH(hostname); - } catch (RuntimeException uhe) { - uhe.printStackTrace(); - } - } - - Log.d("DNS", "try hard coded IPs"); - // let's check if there's an hard-coded IP we can use - ProviderObservable observable = ProviderObservable.getInstance(); - Provider currentProvider; - if (observable.getProviderForDns() != null) { - currentProvider = observable.getProviderForDns(); - } else { - currentProvider = observable.getCurrentProvider(); - } - String ip = currentProvider.getIpForHostname(hostname); - if (!ip.isEmpty()) { - VpnStatus.logWarning("[API] Normal DNS resolution for " + hostname + " seems to be blocked. Circumventing."); - ArrayList<InetAddress> addresses = new ArrayList<>(); - addresses.add(InetAddress.getByAddress(hostname, IPAddress.asBytes(ip))); - return addresses; - } else { - VpnStatus.logWarning("[API] Could not resolve DNS for " + hostname); - throw new UnknownHostException("Hostname " + hostname + " not found"); - } + return null; } } - private List<InetAddress> lookupDoH(@NonNull String hostname) throws RuntimeException, UnknownHostException { + private List<InetAddress> tryLookupDoH(@NonNull String hostname) throws UnknownHostException { DnsOverHttps ahablitzDoHClient = new DnsOverHttps.Builder().client(dohHttpClient) .url(HttpUrl.get("https://blitz.ahadns.com")) .build(); @@ -86,7 +87,7 @@ class DnsResolver implements Dns { Log.d("DNS", "DoH via blitz.ahadns.com"); return ahablitzDoHClient.lookup(hostname); } catch (UnknownHostException e) { - e.printStackTrace(); + e.printStackTrace(); Log.e("DNS", "DoH via blitz.ahadns.com failed"); } @@ -108,7 +109,13 @@ class DnsResolver implements Dns { .bootstrapDnsHosts(getByName("1.1.1.1"), getByName("1.0.0.1")) .build(); - Log.d("DNS", "DoH via cloudflare 1.1.1.1"); - return cloudFlareDoHClient.lookup(hostname); + try { + Log.d("DNS", "DoH via cloudflare 1.1.1.1"); + return cloudFlareDoHClient.lookup(hostname); + } catch (UnknownHostException e) { + e.printStackTrace(); + Log.e("DNS", "DoH via cloudflare failed"); + } + return null; } } |