| /* |
| * Copyright (C) 2018 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package android.net.dns; |
| |
| import android.net.Network; |
| import android.net.NetworkUtils; |
| import android.system.GaiException; |
| import android.system.OsConstants; |
| import android.system.StructAddrinfo; |
| |
| import libcore.io.Libcore; |
| |
| import java.net.InetAddress; |
| import java.net.UnknownHostException; |
| |
| |
| /** |
| * DNS resolution utility class. |
| * |
| * @hide |
| */ |
| public class ResolvUtil { |
| // Non-portable DNS resolution flag. |
| private static final long NETID_USE_LOCAL_NAMESERVERS = 0x80000000L; |
| |
| private ResolvUtil() {} |
| |
| public static InetAddress[] blockingResolveAllLocally(Network network, String name) |
| throws UnknownHostException { |
| final StructAddrinfo hints = new StructAddrinfo(); |
| // Unnecessary, but expressly no AI_ADDRCONFIG. |
| hints.ai_flags = 0; |
| // Fetch all IP addresses at once to minimize re-resolution. |
| hints.ai_family = OsConstants.AF_UNSPEC; |
| hints.ai_socktype = OsConstants.SOCK_DGRAM; |
| |
| final Network networkForResolv = getNetworkWithUseLocalNameserversFlag(network); |
| |
| try { |
| return Libcore.os.android_getaddrinfo(name, hints, (int) networkForResolv.netId); |
| } catch (GaiException gai) { |
| gai.rethrowAsUnknownHostException(name + ": TLS-bypass resolution failed"); |
| return null; // keep compiler quiet |
| } |
| } |
| |
| public static Network getNetworkWithUseLocalNameserversFlag(Network network) { |
| final long netidForResolv = NETID_USE_LOCAL_NAMESERVERS | (long) network.netId; |
| return new Network((int) netidForResolv); |
| } |
| } |