| /* |
| * Copyright (C) 2019 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.util; |
| |
| import android.content.Context; |
| import android.content.pm.PackageManager.NameNotFoundException; |
| import android.provider.DeviceConfig; |
| import android.util.Log; |
| import android.util.SparseArray; |
| |
| import androidx.annotation.NonNull; |
| import androidx.annotation.Nullable; |
| |
| import java.io.FileDescriptor; |
| import java.io.IOException; |
| import java.net.Inet4Address; |
| import java.net.Inet6Address; |
| import java.net.InetAddress; |
| import java.net.SocketException; |
| import java.util.List; |
| import java.util.function.Predicate; |
| |
| /** |
| * Collection of utilities for the network stack. |
| */ |
| public class NetworkStackUtils { |
| private static final String TAG = "NetworkStackUtils"; |
| |
| /** |
| * A list of captive portal detection specifications used in addition to the fallback URLs. |
| * Each spec has the format url@@/@@statusCodeRegex@@/@@contentRegex. Specs are separated |
| * by "@@,@@". |
| */ |
| public static final String CAPTIVE_PORTAL_FALLBACK_PROBE_SPECS = |
| "captive_portal_fallback_probe_specs"; |
| |
| /** |
| * A comma separated list of URLs used for captive portal detection in addition to the |
| * fallback HTTP url associated with the CAPTIVE_PORTAL_FALLBACK_URL settings. |
| */ |
| public static final String CAPTIVE_PORTAL_OTHER_FALLBACK_URLS = |
| "captive_portal_other_fallback_urls"; |
| |
| /** |
| * A comma separated list of URLs used for captive portal detection in addition to the HTTP url |
| * associated with the CAPTIVE_PORTAL_HTTP_URL settings. |
| */ |
| public static final String CAPTIVE_PORTAL_OTHER_HTTP_URLS = "captive_portal_other_http_urls"; |
| |
| /** |
| * A comma separated list of URLs used for network validation. in addition to the HTTPS url |
| * associated with the CAPTIVE_PORTAL_HTTPS_URL settings. |
| */ |
| public static final String CAPTIVE_PORTAL_OTHER_HTTPS_URLS = "captive_portal_other_https_urls"; |
| |
| /** |
| * Which User-Agent string to use in the header of the captive portal detection probes. |
| * The User-Agent field is unset when this setting has no value (HttpUrlConnection default). |
| */ |
| public static final String CAPTIVE_PORTAL_USER_AGENT = "captive_portal_user_agent"; |
| |
| /** |
| * Whether to use HTTPS for network validation. This is enabled by default and the setting |
| * needs to be set to 0 to disable it. This setting is a misnomer because captive portals |
| * don't actually use HTTPS, but it's consistent with the other settings. |
| */ |
| public static final String CAPTIVE_PORTAL_USE_HTTPS = "captive_portal_use_https"; |
| |
| /** |
| * The URL used for HTTPS captive portal detection upon a new connection. |
| * A 204 response code from the server is used for validation. |
| */ |
| public static final String CAPTIVE_PORTAL_HTTPS_URL = "captive_portal_https_url"; |
| |
| /** |
| * The URL used for HTTP captive portal detection upon a new connection. |
| * A 204 response code from the server is used for validation. |
| */ |
| public static final String CAPTIVE_PORTAL_HTTP_URL = "captive_portal_http_url"; |
| |
| /** |
| * A test URL used to override configuration settings and overlays for the network validation |
| * HTTPS URL, when set in {@link android.provider.DeviceConfig} configuration. |
| * |
| * <p>This URL will be ignored if the host is not "localhost" (it can only be used to test with |
| * a local test server), and must not be set in production scenarios (as enforced by CTS tests). |
| * |
| * <p>{@link #TEST_URL_EXPIRATION_TIME} must also be set to use this setting. |
| */ |
| public static final String TEST_CAPTIVE_PORTAL_HTTPS_URL = "test_captive_portal_https_url"; |
| |
| /** |
| * A test URL used to override configuration settings and overlays for the network validation |
| * HTTP URL, when set in {@link android.provider.DeviceConfig} configuration. |
| * |
| * <p>This URL will be ignored if the host is not "localhost" (it can only be used to test with |
| * a local test server), and must not be set in production scenarios (as enforced by CTS tests). |
| * |
| * <p>{@link #TEST_URL_EXPIRATION_TIME} must also be set to use this setting. |
| */ |
| public static final String TEST_CAPTIVE_PORTAL_HTTP_URL = "test_captive_portal_http_url"; |
| |
| /** |
| * Expiration time of the test URL, in ms, relative to {@link System#currentTimeMillis()}. |
| * |
| * <p>After this expiration time, test URLs will be ignored. They will also be ignored if |
| * the expiration time is more than 10 minutes in the future, to avoid misconfiguration |
| * following test runs. |
| */ |
| public static final String TEST_URL_EXPIRATION_TIME = "test_url_expiration_time"; |
| |
| /** |
| * The URL used for fallback HTTP captive portal detection when previous HTTP |
| * and HTTPS captive portal detection attemps did not return a conclusive answer. |
| */ |
| public static final String CAPTIVE_PORTAL_FALLBACK_URL = "captive_portal_fallback_url"; |
| |
| /** |
| * What to do when connecting a network that presents a captive portal. |
| * Must be one of the CAPTIVE_PORTAL_MODE_* constants above. |
| * |
| * The default for this setting is CAPTIVE_PORTAL_MODE_PROMPT. |
| */ |
| public static final String CAPTIVE_PORTAL_MODE = "captive_portal_mode"; |
| |
| /** |
| * Don't attempt to detect captive portals. |
| */ |
| public static final int CAPTIVE_PORTAL_MODE_IGNORE = 0; |
| |
| /** |
| * When detecting a captive portal, display a notification that |
| * prompts the user to sign in. |
| */ |
| public static final int CAPTIVE_PORTAL_MODE_PROMPT = 1; |
| |
| /** |
| * When detecting a captive portal, immediately disconnect from the |
| * network and do not reconnect to that network in the future. |
| */ |
| public static final int CAPTIVE_PORTAL_MODE_AVOID = 2; |
| |
| /** |
| * DNS probe timeout for network validation. Enough for 3 DNS queries 5 seconds apart. |
| */ |
| public static final int DEFAULT_CAPTIVE_PORTAL_DNS_PROBE_TIMEOUT = 12500; |
| |
| /** |
| * List of fallback probe specs to use for detecting captive portals. This is an alternative to |
| * fallback URLs that provides more flexibility on detection rules. Empty, so unused by default. |
| */ |
| public static final String[] DEFAULT_CAPTIVE_PORTAL_FALLBACK_PROBE_SPECS = |
| new String[] {}; |
| |
| /** |
| * The default list of HTTP URLs to use for detecting captive portals. |
| */ |
| public static final String[] DEFAULT_CAPTIVE_PORTAL_HTTP_URLS = |
| new String [] {"http://connectivitycheck.gstatic.com/generate_204"}; |
| |
| /** |
| * The default list of HTTPS URLs for network validation, to use for confirming internet |
| * connectivity. |
| */ |
| public static final String[] DEFAULT_CAPTIVE_PORTAL_HTTPS_URLS = |
| new String [] {"https://www.google.com/generate_204"}; |
| |
| /** |
| * @deprecated Considering boolean experiment flag is likely to cause misconfiguration |
| * particularly when NetworkStack module rolls back to previous version. It's |
| * much safer to determine whether or not to enable one specific experimental |
| * feature by comparing flag version with module version. |
| */ |
| @Deprecated |
| public static final String DHCP_INIT_REBOOT_ENABLED = "dhcp_init_reboot_enabled"; |
| |
| /** |
| * @deprecated See above explanation. |
| */ |
| @Deprecated |
| public static final String DHCP_RAPID_COMMIT_ENABLED = "dhcp_rapid_commit_enabled"; |
| |
| /** |
| * Minimum module version at which to enable the DHCP INIT-REBOOT state. |
| */ |
| public static final String DHCP_INIT_REBOOT_VERSION = "dhcp_init_reboot_version"; |
| |
| /** |
| * Minimum module version at which to enable the DHCP Rapid Commit option. |
| */ |
| public static final String DHCP_RAPID_COMMIT_VERSION = "dhcp_rapid_commit_version"; |
| |
| /** |
| * Minimum module version at which to enable the IP address conflict detection feature. |
| */ |
| public static final String DHCP_IP_CONFLICT_DETECT_VERSION = "dhcp_ip_conflict_detect_version"; |
| |
| /** |
| * Minimum module version at which to enable dismissal CaptivePortalLogin app in validated |
| * network feature. CaptivePortalLogin app will also use validation facilities in |
| * {@link NetworkMonitor} to perform portal validation if feature is enabled. |
| */ |
| public static final String DISMISS_PORTAL_IN_VALIDATED_NETWORK = |
| "dismiss_portal_in_validated_network"; |
| |
| /** |
| * Experiment flag to enable considering DNS probes returning private IP addresses as failed |
| * when attempting to detect captive portals. |
| * |
| * This flag is enabled if !=0 and less than the module APK version. |
| */ |
| public static final String DNS_PROBE_PRIVATE_IP_NO_INTERNET_VERSION = |
| "dns_probe_private_ip_no_internet"; |
| |
| /** |
| * Experiment flag to enable validation metrics sent by NetworkMonitor. |
| * |
| * Metrics are sent by default. They can be disabled by setting the flag to a number greater |
| * than the APK version (for example 999999999). |
| * @see #isFeatureEnabled(Context, String, String, boolean) |
| */ |
| public static final String VALIDATION_METRICS_VERSION = "validation_metrics_version"; |
| |
| static { |
| System.loadLibrary("networkstackutilsjni"); |
| } |
| |
| /** |
| * @return True if the array is null or 0-length. |
| */ |
| public static <T> boolean isEmpty(T[] array) { |
| return array == null || array.length == 0; |
| } |
| |
| /** |
| * Close a socket, ignoring any exception while closing. |
| */ |
| public static void closeSocketQuietly(FileDescriptor fd) { |
| try { |
| SocketUtils.closeSocket(fd); |
| } catch (IOException ignored) { |
| } |
| } |
| |
| /** |
| * Returns an int array from the given Integer list. |
| */ |
| public static int[] convertToIntArray(@NonNull List<Integer> list) { |
| int[] array = new int[list.size()]; |
| for (int i = 0; i < list.size(); i++) { |
| array[i] = list.get(i); |
| } |
| return array; |
| } |
| |
| /** |
| * Returns a long array from the given long list. |
| */ |
| public static long[] convertToLongArray(@NonNull List<Long> list) { |
| long[] array = new long[list.size()]; |
| for (int i = 0; i < list.size(); i++) { |
| array[i] = list.get(i); |
| } |
| return array; |
| } |
| |
| /** |
| * @return True if there exists at least one element in the sparse array for which |
| * condition {@code predicate} |
| */ |
| public static <T> boolean any(SparseArray<T> array, Predicate<T> predicate) { |
| for (int i = 0; i < array.size(); ++i) { |
| if (predicate.test(array.valueAt(i))) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * Look up the value of a property for a particular namespace from {@link DeviceConfig}. |
| * @param namespace The namespace containing the property to look up. |
| * @param name The name of the property to look up. |
| * @param defaultValue The value to return if the property does not exist or has no valid value. |
| * @return the corresponding value, or defaultValue if none exists. |
| */ |
| @Nullable |
| public static String getDeviceConfigProperty(@NonNull String namespace, @NonNull String name, |
| @Nullable String defaultValue) { |
| String value = DeviceConfig.getProperty(namespace, name); |
| return value != null ? value : defaultValue; |
| } |
| |
| /** |
| * Look up the value of a property for a particular namespace from {@link DeviceConfig}. |
| * @param namespace The namespace containing the property to look up. |
| * @param name The name of the property to look up. |
| * @param defaultValue The value to return if the property does not exist or its value is null. |
| * @return the corresponding value, or defaultValue if none exists. |
| */ |
| public static int getDeviceConfigPropertyInt(@NonNull String namespace, @NonNull String name, |
| int defaultValue) { |
| String value = getDeviceConfigProperty(namespace, name, null /* defaultValue */); |
| try { |
| return (value != null) ? Integer.parseInt(value) : defaultValue; |
| } catch (NumberFormatException e) { |
| return defaultValue; |
| } |
| } |
| |
| /** |
| * Look up the value of a property for a particular namespace from {@link DeviceConfig}. |
| * @param namespace The namespace containing the property to look up. |
| * @param name The name of the property to look up. |
| * @param minimumValue The minimum value of a property. |
| * @param maximumValue The maximum value of a property. |
| * @param defaultValue The value to return if the property does not exist or its value is null. |
| * @return the corresponding value, or defaultValue if none exists or the fetched value is |
| * greater than maximumValue. |
| */ |
| public static int getDeviceConfigPropertyInt(@NonNull String namespace, @NonNull String name, |
| int minimumValue, int maximumValue, int defaultValue) { |
| int value = getDeviceConfigPropertyInt(namespace, name, defaultValue); |
| if (value < minimumValue || value > maximumValue) return defaultValue; |
| return value; |
| } |
| |
| /** |
| * Look up the value of a property for a particular namespace from {@link DeviceConfig}. |
| * @param namespace The namespace containing the property to look up. |
| * @param name The name of the property to look up. |
| * @param defaultValue The value to return if the property does not exist or its value is null. |
| * @return the corresponding value, or defaultValue if none exists. |
| */ |
| public static boolean getDeviceConfigPropertyBoolean(@NonNull String namespace, |
| @NonNull String name, boolean defaultValue) { |
| String value = getDeviceConfigProperty(namespace, name, null /* defaultValue */); |
| return (value != null) ? Boolean.parseBoolean(value) : defaultValue; |
| } |
| |
| /** |
| * Check whether or not one specific experimental feature for a particular namespace from |
| * {@link DeviceConfig} is enabled by comparing NetworkStack module version {@link NetworkStack} |
| * with current version of property. If this property version is valid, the corresponding |
| * experimental feature would be enabled, otherwise disabled. |
| * |
| * This is useful to ensure that if a module install is rolled back, flags are not left fully |
| * rolled out on a version where they have not been well tested. |
| * @param context The global context information about an app environment. |
| * @param namespace The namespace containing the property to look up. |
| * @param name The name of the property to look up. |
| * @return true if this feature is enabled, or false if disabled. |
| */ |
| public static boolean isFeatureEnabled(@NonNull Context context, @NonNull String namespace, |
| @NonNull String name) { |
| return isFeatureEnabled(context, namespace, name, false /* defaultEnabled */); |
| } |
| |
| /** |
| * Check whether or not one specific experimental feature for a particular namespace from |
| * {@link DeviceConfig} is enabled by comparing NetworkStack module version {@link NetworkStack} |
| * with current version of property. If this property version is valid, the corresponding |
| * experimental feature would be enabled, otherwise disabled. |
| * |
| * This is useful to ensure that if a module install is rolled back, flags are not left fully |
| * rolled out on a version where they have not been well tested. |
| * @param context The global context information about an app environment. |
| * @param namespace The namespace containing the property to look up. |
| * @param name The name of the property to look up. |
| * @param defaultEnabled The value to return if the property does not exist or its value is |
| * null. |
| * @return true if this feature is enabled, or false if disabled. |
| */ |
| public static boolean isFeatureEnabled(@NonNull Context context, @NonNull String namespace, |
| @NonNull String name, boolean defaultEnabled) { |
| try { |
| final int propertyVersion = getDeviceConfigPropertyInt(namespace, name, |
| 0 /* default value */); |
| final long packageVersion = context.getPackageManager().getPackageInfo( |
| context.getPackageName(), 0).getLongVersionCode(); |
| return (propertyVersion == 0 && defaultEnabled) |
| || (propertyVersion != 0 && packageVersion >= (long) propertyVersion); |
| } catch (NameNotFoundException e) { |
| Log.e(TAG, "Could not find the package name", e); |
| return false; |
| } |
| } |
| |
| /** |
| * Attaches a socket filter that accepts DHCP packets to the given socket. |
| */ |
| public static native void attachDhcpFilter(FileDescriptor fd) throws SocketException; |
| |
| /** |
| * Attaches a socket filter that accepts ICMPv6 router advertisements to the given socket. |
| * @param fd the socket's {@link FileDescriptor}. |
| * @param packetType the hardware address type, one of ARPHRD_*. |
| */ |
| public static native void attachRaFilter(FileDescriptor fd, int packetType) |
| throws SocketException; |
| |
| /** |
| * Attaches a socket filter that accepts L2-L4 signaling traffic required for IP connectivity. |
| * |
| * This includes: all ARP, ICMPv6 RS/RA/NS/NA messages, and DHCPv4 exchanges. |
| * |
| * @param fd the socket's {@link FileDescriptor}. |
| * @param packetType the hardware address type, one of ARPHRD_*. |
| */ |
| public static native void attachControlPacketFilter(FileDescriptor fd, int packetType) |
| throws SocketException; |
| |
| /** |
| * Add an entry into the ARP cache. |
| */ |
| public static void addArpEntry(Inet4Address ipv4Addr, android.net.MacAddress ethAddr, |
| String ifname, FileDescriptor fd) throws IOException { |
| addArpEntry(ethAddr.toByteArray(), ipv4Addr.getAddress(), ifname, fd); |
| } |
| |
| private static native void addArpEntry(byte[] ethAddr, byte[] netAddr, String ifname, |
| FileDescriptor fd) throws IOException; |
| |
| /** |
| * Return IP address and port in a string format. |
| */ |
| public static String addressAndPortToString(InetAddress address, int port) { |
| return String.format( |
| (address instanceof Inet6Address) ? "[%s]:%d" : "%s:%d", |
| address.getHostAddress(), port); |
| } |
| |
| /** |
| * Return true if the provided address is non-null and an IPv6 Unique Local Address (RFC4193). |
| */ |
| public static boolean isIPv6ULA(@Nullable InetAddress addr) { |
| return addr instanceof Inet6Address |
| && ((addr.getAddress()[0] & 0xfe) == 0xfc); |
| } |
| |
| /** |
| * Returns the {@code int} nearest in value to {@code value}. |
| * |
| * @param value any {@code long} value |
| * @return the same value cast to {@code int} if it is in the range of the {@code int} |
| * type, {@link Integer#MAX_VALUE} if it is too large, or {@link Integer#MIN_VALUE} if |
| * it is too small |
| */ |
| public static int saturatedCast(long value) { |
| if (value > Integer.MAX_VALUE) { |
| return Integer.MAX_VALUE; |
| } |
| if (value < Integer.MIN_VALUE) { |
| return Integer.MIN_VALUE; |
| } |
| return (int) value; |
| } |
| } |