| /* |
| * Copyright (C) 2008 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; |
| |
| import static android.system.OsConstants.AF_INET; |
| import static android.system.OsConstants.AF_INET6; |
| |
| import android.annotation.NonNull; |
| import android.annotation.UnsupportedAppUsage; |
| import android.net.shared.Inet4AddressUtils; |
| import android.os.Build; |
| import android.system.ErrnoException; |
| import android.system.Os; |
| import android.util.Log; |
| import android.util.Pair; |
| |
| import java.io.FileDescriptor; |
| import java.math.BigInteger; |
| import java.net.Inet4Address; |
| import java.net.Inet6Address; |
| import java.net.InetAddress; |
| import java.net.SocketException; |
| import java.net.UnknownHostException; |
| import java.util.Collection; |
| import java.util.Locale; |
| import java.util.TreeSet; |
| |
| /** |
| * Native methods for managing network interfaces. |
| * |
| * {@hide} |
| */ |
| public class NetworkUtils { |
| |
| private static final String TAG = "NetworkUtils"; |
| |
| /** |
| * Attaches a socket filter that drops all of incoming packets. |
| * @param fd the socket's {@link FileDescriptor}. |
| */ |
| public static native void attachDropAllBPFFilter(FileDescriptor fd) throws SocketException; |
| |
| /** |
| * Detaches a socket filter. |
| * @param fd the socket's {@link FileDescriptor}. |
| */ |
| public static native void detachBPFFilter(FileDescriptor fd) throws SocketException; |
| |
| /** |
| * Configures a socket for receiving ICMPv6 router solicitations and sending advertisements. |
| * @param fd the socket's {@link FileDescriptor}. |
| * @param ifIndex the interface index. |
| */ |
| public native static void setupRaSocket(FileDescriptor fd, int ifIndex) throws SocketException; |
| |
| /** |
| * Binds the current process to the network designated by {@code netId}. All sockets created |
| * in the future (and not explicitly bound via a bound {@link SocketFactory} (see |
| * {@link Network#getSocketFactory}) will be bound to this network. Note that if this |
| * {@code Network} ever disconnects all sockets created in this way will cease to work. This |
| * is by design so an application doesn't accidentally use sockets it thinks are still bound to |
| * a particular {@code Network}. Passing NETID_UNSET clears the binding. |
| */ |
| public native static boolean bindProcessToNetwork(int netId); |
| |
| /** |
| * Return the netId last passed to {@link #bindProcessToNetwork}, or NETID_UNSET if |
| * {@link #unbindProcessToNetwork} has been called since {@link #bindProcessToNetwork}. |
| */ |
| public native static int getBoundNetworkForProcess(); |
| |
| /** |
| * Binds host resolutions performed by this process to the network designated by {@code netId}. |
| * {@link #bindProcessToNetwork} takes precedence over this setting. Passing NETID_UNSET clears |
| * the binding. |
| * |
| * @deprecated This is strictly for legacy usage to support startUsingNetworkFeature(). |
| */ |
| @Deprecated |
| public native static boolean bindProcessToNetworkForHostResolution(int netId); |
| |
| /** |
| * Explicitly binds {@code socketfd} to the network designated by {@code netId}. This |
| * overrides any binding via {@link #bindProcessToNetwork}. |
| * @return 0 on success or negative errno on failure. |
| */ |
| public native static int bindSocketToNetwork(int socketfd, int netId); |
| |
| /** |
| * Protect {@code fd} from VPN connections. After protecting, data sent through |
| * this socket will go directly to the underlying network, so its traffic will not be |
| * forwarded through the VPN. |
| */ |
| @UnsupportedAppUsage |
| public static boolean protectFromVpn(FileDescriptor fd) { |
| return protectFromVpn(fd.getInt$()); |
| } |
| |
| /** |
| * Protect {@code socketfd} from VPN connections. After protecting, data sent through |
| * this socket will go directly to the underlying network, so its traffic will not be |
| * forwarded through the VPN. |
| */ |
| public native static boolean protectFromVpn(int socketfd); |
| |
| /** |
| * Determine if {@code uid} can access network designated by {@code netId}. |
| * @return {@code true} if {@code uid} can access network, {@code false} otherwise. |
| */ |
| public native static boolean queryUserAccess(int uid, int netId); |
| |
| /** |
| * DNS resolver series jni method. |
| * Issue the query {@code msg} on the network designated by {@code netId}. |
| * {@code flags} is an additional config to control actual querying behavior. |
| * @return a file descriptor to watch for read events |
| */ |
| public static native FileDescriptor resNetworkSend( |
| int netId, byte[] msg, int msglen, int flags) throws ErrnoException; |
| |
| /** |
| * DNS resolver series jni method. |
| * Look up the {@code nsClass} {@code nsType} Resource Record (RR) associated |
| * with Domain Name {@code dname} on the network designated by {@code netId}. |
| * {@code flags} is an additional config to control actual querying behavior. |
| * @return a file descriptor to watch for read events |
| */ |
| public static native FileDescriptor resNetworkQuery( |
| int netId, String dname, int nsClass, int nsType, int flags) throws ErrnoException; |
| |
| /** |
| * DNS resolver series jni method. |
| * Read a result for the query associated with the {@code fd}. |
| * @return a byte array containing blob answer |
| */ |
| public static native byte[] resNetworkResult(FileDescriptor fd) throws ErrnoException; |
| |
| /** |
| * DNS resolver series jni method. |
| * Attempts to cancel the in-progress query associated with the {@code fd}. |
| */ |
| public static native void resNetworkCancel(FileDescriptor fd); |
| |
| /** |
| * Get the tcp repair window associated with the {@code fd}. |
| * |
| * @param fd the tcp socket's {@link FileDescriptor}. |
| * @return a {@link TcpRepairWindow} object indicates tcp window size. |
| */ |
| public static native TcpRepairWindow getTcpRepairWindow(FileDescriptor fd) |
| throws ErrnoException; |
| |
| /** |
| * @see Inet4AddressUtils#intToInet4AddressHTL(int) |
| * @deprecated Use either {@link Inet4AddressUtils#intToInet4AddressHTH(int)} |
| * or {@link Inet4AddressUtils#intToInet4AddressHTL(int)} |
| */ |
| @Deprecated |
| @UnsupportedAppUsage |
| public static InetAddress intToInetAddress(int hostAddress) { |
| return Inet4AddressUtils.intToInet4AddressHTL(hostAddress); |
| } |
| |
| /** |
| * @see Inet4AddressUtils#inet4AddressToIntHTL(Inet4Address) |
| * @deprecated Use either {@link Inet4AddressUtils#inet4AddressToIntHTH(Inet4Address)} |
| * or {@link Inet4AddressUtils#inet4AddressToIntHTL(Inet4Address)} |
| */ |
| @Deprecated |
| public static int inetAddressToInt(Inet4Address inetAddr) |
| throws IllegalArgumentException { |
| return Inet4AddressUtils.inet4AddressToIntHTL(inetAddr); |
| } |
| |
| /** |
| * @see Inet4AddressUtils#prefixLengthToV4NetmaskIntHTL(int) |
| * @deprecated Use either {@link Inet4AddressUtils#prefixLengthToV4NetmaskIntHTH(int)} |
| * or {@link Inet4AddressUtils#prefixLengthToV4NetmaskIntHTL(int)} |
| */ |
| @Deprecated |
| @UnsupportedAppUsage |
| public static int prefixLengthToNetmaskInt(int prefixLength) |
| throws IllegalArgumentException { |
| return Inet4AddressUtils.prefixLengthToV4NetmaskIntHTL(prefixLength); |
| } |
| |
| /** |
| * Convert a IPv4 netmask integer to a prefix length |
| * @param netmask as an integer (0xff000000 for a /8 subnet) |
| * @return the network prefix length |
| */ |
| public static int netmaskIntToPrefixLength(int netmask) { |
| return Integer.bitCount(netmask); |
| } |
| |
| /** |
| * Convert an IPv4 netmask to a prefix length, checking that the netmask is contiguous. |
| * @param netmask as a {@code Inet4Address}. |
| * @return the network prefix length |
| * @throws IllegalArgumentException the specified netmask was not contiguous. |
| * @hide |
| * @deprecated use {@link Inet4AddressUtils#netmaskToPrefixLength(Inet4Address)} |
| */ |
| @UnsupportedAppUsage |
| @Deprecated |
| public static int netmaskToPrefixLength(Inet4Address netmask) { |
| // This is only here because some apps seem to be using it (@UnsupportedAppUsage). |
| return Inet4AddressUtils.netmaskToPrefixLength(netmask); |
| } |
| |
| |
| /** |
| * Create an InetAddress from a string where the string must be a standard |
| * representation of a V4 or V6 address. Avoids doing a DNS lookup on failure |
| * but it will throw an IllegalArgumentException in that case. |
| * @param addrString |
| * @return the InetAddress |
| * @hide |
| * @deprecated Use {@link InetAddresses#parseNumericAddress(String)}, if possible. |
| */ |
| @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P) |
| @Deprecated |
| public static InetAddress numericToInetAddress(String addrString) |
| throws IllegalArgumentException { |
| return InetAddress.parseNumericAddress(addrString); |
| } |
| |
| /** |
| * Masks a raw IP address byte array with the specified prefix length. |
| */ |
| public static void maskRawAddress(byte[] array, int prefixLength) { |
| if (prefixLength < 0 || prefixLength > array.length * 8) { |
| throw new RuntimeException("IP address with " + array.length + |
| " bytes has invalid prefix length " + prefixLength); |
| } |
| |
| int offset = prefixLength / 8; |
| int remainder = prefixLength % 8; |
| byte mask = (byte)(0xFF << (8 - remainder)); |
| |
| if (offset < array.length) array[offset] = (byte)(array[offset] & mask); |
| |
| offset++; |
| |
| for (; offset < array.length; offset++) { |
| array[offset] = 0; |
| } |
| } |
| |
| /** |
| * Get InetAddress masked with prefixLength. Will never return null. |
| * @param address the IP address to mask with |
| * @param prefixLength the prefixLength used to mask the IP |
| */ |
| public static InetAddress getNetworkPart(InetAddress address, int prefixLength) { |
| byte[] array = address.getAddress(); |
| maskRawAddress(array, prefixLength); |
| |
| InetAddress netPart = null; |
| try { |
| netPart = InetAddress.getByAddress(array); |
| } catch (UnknownHostException e) { |
| throw new RuntimeException("getNetworkPart error - " + e.toString()); |
| } |
| return netPart; |
| } |
| |
| /** |
| * Returns the implicit netmask of an IPv4 address, as was the custom before 1993. |
| */ |
| @UnsupportedAppUsage |
| public static int getImplicitNetmask(Inet4Address address) { |
| // Only here because it seems to be used by apps |
| return Inet4AddressUtils.getImplicitNetmask(address); |
| } |
| |
| /** |
| * Utility method to parse strings such as "192.0.2.5/24" or "2001:db8::cafe:d00d/64". |
| * @hide |
| */ |
| public static Pair<InetAddress, Integer> parseIpAndMask(String ipAndMaskString) { |
| InetAddress address = null; |
| int prefixLength = -1; |
| try { |
| String[] pieces = ipAndMaskString.split("/", 2); |
| prefixLength = Integer.parseInt(pieces[1]); |
| address = InetAddress.parseNumericAddress(pieces[0]); |
| } catch (NullPointerException e) { // Null string. |
| } catch (ArrayIndexOutOfBoundsException e) { // No prefix length. |
| } catch (NumberFormatException e) { // Non-numeric prefix. |
| } catch (IllegalArgumentException e) { // Invalid IP address. |
| } |
| |
| if (address == null || prefixLength == -1) { |
| throw new IllegalArgumentException("Invalid IP address and mask " + ipAndMaskString); |
| } |
| |
| return new Pair<InetAddress, Integer>(address, prefixLength); |
| } |
| |
| /** |
| * Check if IP address type is consistent between two InetAddress. |
| * @return true if both are the same type. False otherwise. |
| */ |
| public static boolean addressTypeMatches(InetAddress left, InetAddress right) { |
| return (((left instanceof Inet4Address) && (right instanceof Inet4Address)) || |
| ((left instanceof Inet6Address) && (right instanceof Inet6Address))); |
| } |
| |
| /** |
| * Convert a 32 char hex string into a Inet6Address. |
| * throws a runtime exception if the string isn't 32 chars, isn't hex or can't be |
| * made into an Inet6Address |
| * @param addrHexString a 32 character hex string representing an IPv6 addr |
| * @return addr an InetAddress representation for the string |
| */ |
| public static InetAddress hexToInet6Address(String addrHexString) |
| throws IllegalArgumentException { |
| try { |
| return numericToInetAddress(String.format(Locale.US, "%s:%s:%s:%s:%s:%s:%s:%s", |
| addrHexString.substring(0,4), addrHexString.substring(4,8), |
| addrHexString.substring(8,12), addrHexString.substring(12,16), |
| addrHexString.substring(16,20), addrHexString.substring(20,24), |
| addrHexString.substring(24,28), addrHexString.substring(28,32))); |
| } catch (Exception e) { |
| Log.e("NetworkUtils", "error in hexToInet6Address(" + addrHexString + "): " + e); |
| throw new IllegalArgumentException(e); |
| } |
| } |
| |
| /** |
| * Create a string array of host addresses from a collection of InetAddresses |
| * @param addrs a Collection of InetAddresses |
| * @return an array of Strings containing their host addresses |
| */ |
| public static String[] makeStrings(Collection<InetAddress> addrs) { |
| String[] result = new String[addrs.size()]; |
| int i = 0; |
| for (InetAddress addr : addrs) { |
| result[i++] = addr.getHostAddress(); |
| } |
| return result; |
| } |
| |
| /** |
| * Trim leading zeros from IPv4 address strings |
| * Our base libraries will interpret that as octel.. |
| * Must leave non v4 addresses and host names alone. |
| * For example, 192.168.000.010 -> 192.168.0.10 |
| * TODO - fix base libraries and remove this function |
| * @param addr a string representing an ip addr |
| * @return a string propertly trimmed |
| */ |
| @UnsupportedAppUsage |
| public static String trimV4AddrZeros(String addr) { |
| if (addr == null) return null; |
| String[] octets = addr.split("\\."); |
| if (octets.length != 4) return addr; |
| StringBuilder builder = new StringBuilder(16); |
| String result = null; |
| for (int i = 0; i < 4; i++) { |
| try { |
| if (octets[i].length() > 3) return addr; |
| builder.append(Integer.parseInt(octets[i])); |
| } catch (NumberFormatException e) { |
| return addr; |
| } |
| if (i < 3) builder.append('.'); |
| } |
| result = builder.toString(); |
| return result; |
| } |
| |
| /** |
| * Returns a prefix set without overlaps. |
| * |
| * This expects the src set to be sorted from shorter to longer. Results are undefined |
| * failing this condition. The returned prefix set is sorted in the same order as the |
| * passed set, with the same comparator. |
| */ |
| private static TreeSet<IpPrefix> deduplicatePrefixSet(final TreeSet<IpPrefix> src) { |
| final TreeSet<IpPrefix> dst = new TreeSet<>(src.comparator()); |
| // Prefixes match addresses that share their upper part up to their length, therefore |
| // the only kind of possible overlap in two prefixes is strict inclusion of the longer |
| // (more restrictive) in the shorter (including equivalence if they have the same |
| // length). |
| // Because prefixes in the src set are sorted from shorter to longer, deduplicating |
| // is done by simply iterating in order, and not adding any longer prefix that is |
| // already covered by a shorter one. |
| newPrefixes: |
| for (IpPrefix newPrefix : src) { |
| for (IpPrefix existingPrefix : dst) { |
| if (existingPrefix.containsPrefix(newPrefix)) { |
| continue newPrefixes; |
| } |
| } |
| dst.add(newPrefix); |
| } |
| return dst; |
| } |
| |
| /** |
| * Returns how many IPv4 addresses match any of the prefixes in the passed ordered set. |
| * |
| * Obviously this returns an integral value between 0 and 2**32. |
| * The behavior is undefined if any of the prefixes is not an IPv4 prefix or if the |
| * set is not ordered smallest prefix to longer prefix. |
| * |
| * @param prefixes the set of prefixes, ordered by length |
| */ |
| public static long routedIPv4AddressCount(final TreeSet<IpPrefix> prefixes) { |
| long routedIPCount = 0; |
| for (final IpPrefix prefix : deduplicatePrefixSet(prefixes)) { |
| if (!prefix.isIPv4()) { |
| Log.wtf(TAG, "Non-IPv4 prefix in routedIPv4AddressCount"); |
| } |
| int rank = 32 - prefix.getPrefixLength(); |
| routedIPCount += 1L << rank; |
| } |
| return routedIPCount; |
| } |
| |
| /** |
| * Returns how many IPv6 addresses match any of the prefixes in the passed ordered set. |
| * |
| * This returns a BigInteger between 0 and 2**128. |
| * The behavior is undefined if any of the prefixes is not an IPv6 prefix or if the |
| * set is not ordered smallest prefix to longer prefix. |
| */ |
| public static BigInteger routedIPv6AddressCount(final TreeSet<IpPrefix> prefixes) { |
| BigInteger routedIPCount = BigInteger.ZERO; |
| for (final IpPrefix prefix : deduplicatePrefixSet(prefixes)) { |
| if (!prefix.isIPv6()) { |
| Log.wtf(TAG, "Non-IPv6 prefix in routedIPv6AddressCount"); |
| } |
| int rank = 128 - prefix.getPrefixLength(); |
| routedIPCount = routedIPCount.add(BigInteger.ONE.shiftLeft(rank)); |
| } |
| return routedIPCount; |
| } |
| |
| private static final int[] ADDRESS_FAMILIES = new int[] {AF_INET, AF_INET6}; |
| |
| /** |
| * Returns true if the hostname is weakly validated. |
| * @param hostname Name of host to validate. |
| * @return True if it's a valid-ish hostname. |
| * |
| * @hide |
| */ |
| public static boolean isWeaklyValidatedHostname(@NonNull String hostname) { |
| // TODO(b/34953048): Use a validation method that permits more accurate, |
| // but still inexpensive, checking of likely valid DNS hostnames. |
| final String weakHostnameRegex = "^[a-zA-Z0-9_.-]+$"; |
| if (!hostname.matches(weakHostnameRegex)) { |
| return false; |
| } |
| |
| for (int address_family : ADDRESS_FAMILIES) { |
| if (Os.inet_pton(address_family, hostname) != null) { |
| return false; |
| } |
| } |
| |
| return true; |
| } |
| } |