script-astra/Android/Sdk/sources/android-35/android/net/nsd/NsdServiceInfo.java

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/*
* Copyright (C) 2012 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.nsd;
import static com.android.net.module.util.HexDump.toHexString;
import android.annotation.FlaggedApi;
import android.annotation.NonNull;
import android.annotation.Nullable;
import android.compat.annotation.UnsupportedAppUsage;
import android.net.Network;
import android.os.Parcel;
import android.os.Parcelable;
import android.text.TextUtils;
import android.util.ArrayMap;
import android.util.ArraySet;
import android.util.Log;
import com.android.net.module.util.InetAddressUtils;
import java.io.UnsupportedEncodingException;
import java.net.InetAddress;
import java.nio.charset.StandardCharsets;
import java.time.Instant;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.StringJoiner;
/**
* A class representing service information for network service discovery
* @see NsdManager
*/
public final class NsdServiceInfo implements Parcelable {
private static final String TAG = "NsdServiceInfo";
@Nullable
private String mServiceName;
@Nullable
private String mServiceType;
private final Set<String> mSubtypes;
private final ArrayMap<String, byte[]> mTxtRecord;
private final List<InetAddress> mHostAddresses;
@Nullable
private String mHostname;
private int mPort;
@Nullable
private byte[] mPublicKey;
@Nullable
private Network mNetwork;
private int mInterfaceIndex;
// The timestamp that one or more resource records associated with this service are considered
// invalid.
@Nullable
private Instant mExpirationTime;
public NsdServiceInfo() {
mSubtypes = new ArraySet<>();
mTxtRecord = new ArrayMap<>();
mHostAddresses = new ArrayList<>();
}
/** @hide */
public NsdServiceInfo(String sn, String rt) {
this();
mServiceName = sn;
mServiceType = rt;
}
/**
* Creates a copy of {@code other}.
*
* @hide
*/
public NsdServiceInfo(@NonNull NsdServiceInfo other) {
mServiceName = other.getServiceName();
mServiceType = other.getServiceType();
mSubtypes = new ArraySet<>(other.getSubtypes());
mTxtRecord = new ArrayMap<>(other.mTxtRecord);
mHostAddresses = new ArrayList<>(other.getHostAddresses());
mHostname = other.getHostname();
mPort = other.getPort();
mNetwork = other.getNetwork();
mInterfaceIndex = other.getInterfaceIndex();
mExpirationTime = other.getExpirationTime();
}
/** Get the service name */
public String getServiceName() {
return mServiceName;
}
/** Set the service name */
public void setServiceName(String s) {
mServiceName = s;
}
/** Get the service type */
public String getServiceType() {
return mServiceType;
}
/** Set the service type */
public void setServiceType(String s) {
mServiceType = s;
}
/**
* Get the host address. The host address is valid for a resolved service.
*
* @deprecated Use {@link #getHostAddresses()} to get the entire list of addresses for the host.
*/
@Deprecated
public InetAddress getHost() {
return mHostAddresses.size() == 0 ? null : mHostAddresses.get(0);
}
/**
* Set the host address
*
* @deprecated Use {@link #setHostAddresses(List)} to set multiple addresses for the host.
*/
@Deprecated
public void setHost(InetAddress s) {
setHostAddresses(Collections.singletonList(s));
}
/**
* Get port number. The port number is valid for a resolved service.
*
* The port is valid for all addresses.
* @see #getHostAddresses()
*/
public int getPort() {
return mPort;
}
/** Set port number */
public void setPort(int p) {
mPort = p;
}
/**
* Get the host addresses.
*
* All host addresses are valid for the resolved service.
* All addresses share the same port
* @see #getPort()
*/
@NonNull
public List<InetAddress> getHostAddresses() {
return new ArrayList<>(mHostAddresses);
}
/** Set the host addresses */
public void setHostAddresses(@NonNull List<InetAddress> addresses) {
mHostAddresses.clear();
mHostAddresses.addAll(addresses);
}
/**
* Get the hostname.
*
* <p>When a service is resolved, it returns the hostname of the resolved service . The top
* level domain ".local." is omitted.
*
* <p>For example, it returns "MyHost" when the service's hostname is "MyHost.local.".
*
* @hide
*/
// @FlaggedApi(NsdManager.Flags.NSD_CUSTOM_HOSTNAME_ENABLED)
@Nullable
public String getHostname() {
return mHostname;
}
/**
* Set a custom hostname for this service instance for registration.
*
* <p>A hostname must be in ".local." domain. The ".local." must be omitted when calling this
* method.
*
* <p>For example, you should call setHostname("MyHost") to use the hostname "MyHost.local.".
*
* <p>If a hostname is set with this method, the addresses set with {@link #setHostAddresses}
* will be registered with the hostname.
*
* <p>If the hostname is null (which is the default for a new {@link NsdServiceInfo}), a random
* hostname is used and the addresses of this device will be registered.
*
* @hide
*/
// @FlaggedApi(NsdManager.Flags.NSD_CUSTOM_HOSTNAME_ENABLED)
public void setHostname(@Nullable String hostname) {
mHostname = hostname;
}
/**
* Set the public key RDATA to be advertised in a KEY RR (RFC 2535).
*
* <p>This is the public key of the key pair used for signing a DNS message (e.g. SRP). Clients
* typically don't need this information, but the KEY RR is usually published to claim the use
* of the DNS name so that another mDNS advertiser can't take over the ownership during a
* temporary power down of the original host device.
*
* <p>When the public key is set to non-null, exactly one KEY RR will be advertised for each of
* the service and host name if they are not null.
*
* @hide // For Thread only
*/
public void setPublicKey(@Nullable byte[] publicKey) {
if (publicKey == null) {
mPublicKey = null;
return;
}
mPublicKey = Arrays.copyOf(publicKey, publicKey.length);
}
/**
* Get the public key RDATA in the KEY RR (RFC 2535) or {@code null} if no KEY RR exists.
*
* @hide // For Thread only
*/
@Nullable
public byte[] getPublicKey() {
if (mPublicKey == null) {
return null;
}
return Arrays.copyOf(mPublicKey, mPublicKey.length);
}
/**
* Unpack txt information from a base-64 encoded byte array.
*
* @param txtRecordsRawBytes The raw base64 encoded byte array.
*
* @hide
*/
public void setTxtRecords(@NonNull byte[] txtRecordsRawBytes) {
// There can be multiple TXT records after each other. Each record has to following format:
//
// byte type required meaning
// ------------------- ------------------- -------- ----------------------------------
// 0 unsigned 8 bit yes size of record excluding this byte
// 1 - n ASCII but not '=' yes key
// n + 1 '=' optional separator of key and value
// n + 2 - record size uninterpreted bytes optional value
//
// Example legal records:
// [11, 'm', 'y', 'k', 'e', 'y', '=', 0x0, 0x4, 0x65, 0x7, 0xff]
// [17, 'm', 'y', 'K', 'e', 'y', 'W', 'i', 't', 'h', 'N', 'o', 'V', 'a', 'l', 'u', 'e', '=']
// [12, 'm', 'y', 'B', 'o', 'o', 'l', 'e', 'a', 'n', 'K', 'e', 'y']
//
// Example corrupted records
// [3, =, 1, 2] <- key is empty
// [3, 0, =, 2] <- key contains non-ASCII character. We handle this by replacing the
// invalid characters instead of skipping the record.
// [30, 'a', =, 2] <- length exceeds total left over bytes in the TXT records array, we
// handle this by reducing the length of the record as needed.
int pos = 0;
while (pos < txtRecordsRawBytes.length) {
// recordLen is an unsigned 8 bit value
int recordLen = txtRecordsRawBytes[pos] & 0xff;
pos += 1;
try {
if (recordLen == 0) {
throw new IllegalArgumentException("Zero sized txt record");
} else if (pos + recordLen > txtRecordsRawBytes.length) {
Log.w(TAG, "Corrupt record length (pos = " + pos + "): " + recordLen);
recordLen = txtRecordsRawBytes.length - pos;
}
// Decode key-value records
String key = null;
byte[] value = null;
int valueLen = 0;
for (int i = pos; i < pos + recordLen; i++) {
if (key == null) {
if (txtRecordsRawBytes[i] == '=') {
key = new String(txtRecordsRawBytes, pos, i - pos,
StandardCharsets.US_ASCII);
}
} else {
if (value == null) {
value = new byte[recordLen - key.length() - 1];
}
value[valueLen] = txtRecordsRawBytes[i];
valueLen++;
}
}
// If '=' was not found we have a boolean record
if (key == null) {
key = new String(txtRecordsRawBytes, pos, recordLen, StandardCharsets.US_ASCII);
}
if (TextUtils.isEmpty(key)) {
// Empty keys are not allowed (RFC6763 6.4)
throw new IllegalArgumentException("Invalid txt record (key is empty)");
}
if (getAttributes().containsKey(key)) {
// When we have a duplicate record, the later ones are ignored (RFC6763 6.4)
throw new IllegalArgumentException("Invalid txt record (duplicate key \"" + key + "\")");
}
setAttribute(key, value);
} catch (IllegalArgumentException e) {
Log.e(TAG, "While parsing txt records (pos = " + pos + "): " + e.getMessage());
}
pos += recordLen;
}
}
/** @hide */
@UnsupportedAppUsage
public void setAttribute(String key, byte[] value) {
if (TextUtils.isEmpty(key)) {
throw new IllegalArgumentException("Key cannot be empty");
}
// Key must be printable US-ASCII, excluding =.
for (int i = 0; i < key.length(); ++i) {
char character = key.charAt(i);
if (character < 0x20 || character > 0x7E) {
throw new IllegalArgumentException("Key strings must be printable US-ASCII");
} else if (character == 0x3D) {
throw new IllegalArgumentException("Key strings must not include '='");
}
}
// Key length + value length must be < 255.
if (key.length() + (value == null ? 0 : value.length) >= 255) {
throw new IllegalArgumentException("Key length + value length must be < 255 bytes");
}
// Warn if key is > 9 characters, as recommended by RFC 6763 section 6.4.
if (key.length() > 9) {
Log.w(TAG, "Key lengths > 9 are discouraged: " + key);
}
// Check against total TXT record size limits.
// Arbitrary 400 / 1300 byte limits taken from RFC 6763 section 6.2.
int txtRecordSize = getTxtRecordSize();
int futureSize = txtRecordSize + key.length() + (value == null ? 0 : value.length) + 2;
if (futureSize > 1300) {
throw new IllegalArgumentException("Total length of attributes must be < 1300 bytes");
} else if (futureSize > 400) {
Log.w(TAG, "Total length of all attributes exceeds 400 bytes; truncation may occur");
}
mTxtRecord.put(key, value);
}
/**
* Add a service attribute as a key/value pair.
*
* <p> Service attributes are included as DNS-SD TXT record pairs.
*
* <p> The key must be US-ASCII printable characters, excluding the '=' character. Values may
* be UTF-8 strings or null. The total length of key + value must be less than 255 bytes.
*
* <p> Keys should be short, ideally no more than 9 characters, and unique per instance of
* {@link NsdServiceInfo}. Calling {@link #setAttribute} twice with the same key will overwrite
* first value.
*/
public void setAttribute(String key, String value) {
try {
setAttribute(key, value == null ? (byte []) null : value.getBytes("UTF-8"));
} catch (UnsupportedEncodingException e) {
throw new IllegalArgumentException("Value must be UTF-8");
}
}
/** Remove an attribute by key */
public void removeAttribute(String key) {
mTxtRecord.remove(key);
}
/**
* Retrieve attributes as a map of String keys to byte[] values. The attributes map is only
* valid for a resolved service.
*
* <p> The returned map is unmodifiable; changes must be made through {@link #setAttribute} and
* {@link #removeAttribute}.
*/
public Map<String, byte[]> getAttributes() {
return Collections.unmodifiableMap(mTxtRecord);
}
private int getTxtRecordSize() {
int txtRecordSize = 0;
for (Map.Entry<String, byte[]> entry : mTxtRecord.entrySet()) {
txtRecordSize += 2; // One for the length byte, one for the = between key and value.
txtRecordSize += entry.getKey().length();
byte[] value = entry.getValue();
txtRecordSize += value == null ? 0 : value.length;
}
return txtRecordSize;
}
/** @hide */
public @NonNull byte[] getTxtRecord() {
int txtRecordSize = getTxtRecordSize();
if (txtRecordSize == 0) {
return new byte[]{};
}
byte[] txtRecord = new byte[txtRecordSize];
int ptr = 0;
for (Map.Entry<String, byte[]> entry : mTxtRecord.entrySet()) {
String key = entry.getKey();
byte[] value = entry.getValue();
// One byte to record the length of this key/value pair.
txtRecord[ptr++] = (byte) (key.length() + (value == null ? 0 : value.length) + 1);
// The key, in US-ASCII.
// Note: use the StandardCharsets const here because it doesn't raise exceptions and we
// already know the key is ASCII at this point.
System.arraycopy(key.getBytes(StandardCharsets.US_ASCII), 0, txtRecord, ptr,
key.length());
ptr += key.length();
// US-ASCII '=' character.
txtRecord[ptr++] = (byte)'=';
// The value, as any raw bytes.
if (value != null) {
System.arraycopy(value, 0, txtRecord, ptr, value.length);
ptr += value.length;
}
}
return txtRecord;
}
/**
* Get the network where the service can be found.
*
* This is set if this {@link NsdServiceInfo} was obtained from
* {@link NsdManager#discoverServices} or {@link NsdManager#resolveService}, unless the service
* was found on a network interface that does not have a {@link Network} (such as a tethering
* downstream, where services are advertised from devices connected to this device via
* tethering).
*/
@Nullable
public Network getNetwork() {
return mNetwork;
}
/**
* Set the network where the service can be found.
* @param network The network, or null to search for, or to announce, the service on all
* connected networks.
*/
public void setNetwork(@Nullable Network network) {
mNetwork = network;
}
/**
* Get the index of the network interface where the service was found.
*
* This is only set when the service was found on an interface that does not have a usable
* Network, in which case {@link #getNetwork()} returns null.
* @return The interface index as per {@link java.net.NetworkInterface#getIndex}, or 0 if unset.
* @hide
*/
public int getInterfaceIndex() {
return mInterfaceIndex;
}
/**
* Set the index of the network interface where the service was found.
* @hide
*/
public void setInterfaceIndex(int interfaceIndex) {
mInterfaceIndex = interfaceIndex;
}
/**
* Sets the subtypes to be advertised for this service instance.
*
* The elements in {@code subtypes} should be the subtype identifiers which have the trailing
* "._sub" removed. For example, the subtype should be "_printer" for
* "_printer._sub._http._tcp.local".
*
* Only one subtype will be registered if multiple elements of {@code subtypes} have the same
* case-insensitive value.
*/
@FlaggedApi(NsdManager.Flags.NSD_SUBTYPES_SUPPORT_ENABLED)
public void setSubtypes(@NonNull Set<String> subtypes) {
mSubtypes.clear();
mSubtypes.addAll(subtypes);
}
/**
* Returns subtypes of this service instance.
*
* When this object is returned by the service discovery/browse APIs (etc. {@link
* NsdManager.DiscoveryListener}), the return value may or may not include the subtypes of this
* service.
*/
@FlaggedApi(NsdManager.Flags.NSD_SUBTYPES_SUPPORT_ENABLED)
@NonNull
public Set<String> getSubtypes() {
return Collections.unmodifiableSet(mSubtypes);
}
/**
* Sets the timestamp after when this service is expired.
*
* Note: the value after the decimal point (in unit of seconds) will be discarded. For
* example, {@code 30} seconds will be used when {@code Duration.ofSeconds(30L, 50_000L)}
* is provided.
*
* @hide
*/
public void setExpirationTime(@Nullable Instant expirationTime) {
if (expirationTime == null) {
mExpirationTime = null;
} else {
mExpirationTime = Instant.ofEpochSecond(expirationTime.getEpochSecond());
}
}
/**
* Returns the timestamp after when this service is expired or {@code null} if it's unknown.
*
* A service is considered expired if any of its DNS record is expired.
*
* Clients that are depending on the refreshness of the service information should not continue
* use this service after the returned timestamp. Instead, clients may re-send queries for the
* service to get updated the service information.
*
* @hide
*/
// @FlaggedApi(NsdManager.Flags.NSD_CUSTOM_TTL_ENABLED)
@Nullable
public Instant getExpirationTime() {
return mExpirationTime;
}
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append("name: ").append(mServiceName)
.append(", type: ").append(mServiceType)
.append(", subtypes: ").append(TextUtils.join(", ", mSubtypes))
.append(", hostAddresses: ").append(TextUtils.join(", ", mHostAddresses))
.append(", hostname: ").append(mHostname)
.append(", port: ").append(mPort)
.append(", network: ").append(mNetwork)
.append(", expirationTime: ").append(mExpirationTime);
final StringJoiner txtJoiner =
new StringJoiner(", " /* delimiter */, "{" /* prefix */, "}" /* suffix */);
sb.append(", txtRecord: ");
for (int i = 0; i < mTxtRecord.size(); i++) {
txtJoiner.add(mTxtRecord.keyAt(i) + "=" + getPrintableTxtValue(mTxtRecord.valueAt(i)));
}
sb.append(txtJoiner.toString());
return sb.toString();
}
/**
* Returns printable string for {@code txtValue}.
*
* If {@code txtValue} contains non-printable ASCII characters, a HEX string with prefix "0x"
* will be returned. Otherwise, the ASCII string of {@code txtValue} is returned.
*
*/
private static String getPrintableTxtValue(@Nullable byte[] txtValue) {
if (txtValue == null) {
return "(null)";
}
if (containsNonPrintableChars(txtValue)) {
return "0x" + toHexString(txtValue);
}
return new String(txtValue, StandardCharsets.US_ASCII);
}
/**
* Returns {@code true} if {@code txtValue} contains non-printable ASCII characters.
*
* The printable characters are in range of [32, 126].
*/
private static boolean containsNonPrintableChars(byte[] txtValue) {
for (int i = 0; i < txtValue.length; i++) {
if (txtValue[i] < 32 || txtValue[i] > 126) {
return true;
}
}
return false;
}
/** Implement the Parcelable interface */
public int describeContents() {
return 0;
}
/** Implement the Parcelable interface */
public void writeToParcel(Parcel dest, int flags) {
dest.writeString(mServiceName);
dest.writeString(mServiceType);
dest.writeStringList(new ArrayList<>(mSubtypes));
dest.writeInt(mPort);
// TXT record key/value pairs.
dest.writeInt(mTxtRecord.size());
for (String key : mTxtRecord.keySet()) {
byte[] value = mTxtRecord.get(key);
if (value != null) {
dest.writeInt(1);
dest.writeInt(value.length);
dest.writeByteArray(value);
} else {
dest.writeInt(0);
}
dest.writeString(key);
}
dest.writeParcelable(mNetwork, 0);
dest.writeInt(mInterfaceIndex);
dest.writeInt(mHostAddresses.size());
for (InetAddress address : mHostAddresses) {
InetAddressUtils.parcelInetAddress(dest, address, flags);
}
dest.writeString(mHostname);
dest.writeLong(mExpirationTime != null ? mExpirationTime.getEpochSecond() : -1);
dest.writeByteArray(mPublicKey);
}
/** Implement the Parcelable interface */
public static final @android.annotation.NonNull Creator<NsdServiceInfo> CREATOR =
new Creator<NsdServiceInfo>() {
public NsdServiceInfo createFromParcel(Parcel in) {
NsdServiceInfo info = new NsdServiceInfo();
info.mServiceName = in.readString();
info.mServiceType = in.readString();
info.setSubtypes(new ArraySet<>(in.createStringArrayList()));
info.mPort = in.readInt();
// TXT record key/value pairs.
int recordCount = in.readInt();
for (int i = 0; i < recordCount; ++i) {
byte[] valueArray = null;
if (in.readInt() == 1) {
int valueLength = in.readInt();
valueArray = new byte[valueLength];
in.readByteArray(valueArray);
}
info.mTxtRecord.put(in.readString(), valueArray);
}
info.mNetwork = in.readParcelable(null, Network.class);
info.mInterfaceIndex = in.readInt();
int size = in.readInt();
for (int i = 0; i < size; i++) {
info.mHostAddresses.add(InetAddressUtils.unparcelInetAddress(in));
}
info.mHostname = in.readString();
final long seconds = in.readLong();
info.setExpirationTime(seconds < 0 ? null : Instant.ofEpochSecond(seconds));
info.mPublicKey = in.createByteArray();
return info;
}
public NsdServiceInfo[] newArray(int size) {
return new NsdServiceInfo[size];
}
};
}