| /* |
| * Copyright (C) 2017 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.wifi.rtt; |
| |
| import android.annotation.NonNull; |
| import android.annotation.Nullable; |
| import android.annotation.SystemApi; |
| import android.net.MacAddress; |
| import android.net.wifi.ScanResult; |
| import android.net.wifi.aware.AttachCallback; |
| import android.net.wifi.aware.DiscoverySessionCallback; |
| import android.net.wifi.aware.IdentityChangedListener; |
| import android.net.wifi.aware.PeerHandle; |
| import android.net.wifi.aware.WifiAwareManager; |
| import android.os.Handler; |
| import android.os.Parcel; |
| import android.os.Parcelable; |
| |
| import java.util.ArrayList; |
| import java.util.List; |
| import java.util.Objects; |
| import java.util.StringJoiner; |
| |
| /** |
| * Defines the ranging request to other devices. The ranging request is built using |
| * {@link RangingRequest.Builder}. |
| * A ranging request is executed using |
| * {@link WifiRttManager#startRanging(RangingRequest, java.util.concurrent.Executor, RangingResultCallback)}. |
| * <p> |
| * The ranging request is a batch request - specifying a set of devices (specified using |
| * {@link RangingRequest.Builder#addAccessPoint(ScanResult)} and |
| * {@link RangingRequest.Builder#addAccessPoints(List)}). |
| */ |
| public final class RangingRequest implements Parcelable { |
| private static final int MAX_PEERS = 10; |
| private static final int DEFAULT_RTT_BURST_SIZE = 8; |
| private static final int MIN_RTT_BURST_SIZE = 2; |
| private static final int MAX_RTT_BURST_SIZE = 31; |
| |
| /** |
| * Returns the maximum number of peers to range which can be specified in a single {@code |
| * RangingRequest}. The limit applies no matter how the peers are added to the request, e.g. |
| * through {@link RangingRequest.Builder#addAccessPoint(ScanResult)} or |
| * {@link RangingRequest.Builder#addAccessPoints(List)}. |
| * |
| * @return Maximum number of peers. |
| */ |
| public static int getMaxPeers() { |
| return MAX_PEERS; |
| } |
| |
| /** |
| * Returns the default RTT burst size used to determine the average range. |
| * |
| * @return the RTT burst size used by default |
| */ |
| public static int getDefaultRttBurstSize() { |
| return DEFAULT_RTT_BURST_SIZE; |
| } |
| |
| /** |
| * Returns the minimum RTT burst size that can be used to determine a average range. |
| * |
| * @return the minimum RTT burst size that can be used |
| */ |
| public static int getMinRttBurstSize() { |
| return MIN_RTT_BURST_SIZE; |
| } |
| |
| /** |
| * Returns the minimum RTT burst size that can be used to determine a average range. |
| * |
| * @return the maximum RTT burst size that can be used |
| */ |
| public static int getMaxRttBurstSize() { |
| return MAX_RTT_BURST_SIZE; |
| } |
| |
| /** @hide */ |
| public final List<ResponderConfig> mRttPeers; |
| |
| /** @hide */ |
| public final int mRttBurstSize; |
| |
| /** @hide */ |
| private RangingRequest(List<ResponderConfig> rttPeers, int rttBurstSize) { |
| mRttPeers = rttPeers; |
| mRttBurstSize = rttBurstSize; |
| } |
| |
| /** |
| * Returns the list of RTT capable responding peers. |
| * |
| * @return the list of RTT capable responding peers in a common system representation |
| * |
| * @hide |
| */ |
| @SystemApi |
| @NonNull |
| public List<ResponderConfig> getRttResponders() { |
| return mRttPeers; |
| } |
| |
| /** |
| * Returns the RTT burst size used to determine the average range. |
| * |
| * @return the RTT burst size used |
| */ |
| public int getRttBurstSize() { |
| return mRttBurstSize; |
| } |
| |
| @Override |
| public int describeContents() { |
| return 0; |
| } |
| |
| @Override |
| public void writeToParcel(Parcel dest, int flags) { |
| dest.writeList(mRttPeers); |
| dest.writeInt(mRttBurstSize); |
| } |
| |
| public static final @android.annotation.NonNull Creator<RangingRequest> CREATOR = new Creator<RangingRequest>() { |
| @Override |
| public RangingRequest[] newArray(int size) { |
| return new RangingRequest[size]; |
| } |
| |
| @Override |
| public RangingRequest createFromParcel(Parcel in) { |
| return new RangingRequest(in.readArrayList(null), in.readInt()); |
| } |
| }; |
| |
| /** @hide */ |
| @Override |
| public String toString() { |
| StringJoiner sj = new StringJoiner(", ", "RangingRequest: mRttPeers=[", "]"); |
| for (ResponderConfig rc : mRttPeers) { |
| sj.add(rc.toString()); |
| } |
| return sj.toString(); |
| } |
| |
| /** @hide */ |
| public void enforceValidity(boolean awareSupported) { |
| if (mRttPeers.size() > MAX_PEERS) { |
| throw new IllegalArgumentException( |
| "Ranging to too many peers requested. Use getMaxPeers() API to get limit."); |
| } |
| for (ResponderConfig peer: mRttPeers) { |
| if (!peer.isValid(awareSupported)) { |
| throw new IllegalArgumentException("Invalid Responder specification"); |
| } |
| } |
| if (mRttBurstSize < getMinRttBurstSize() || mRttBurstSize > getMaxRttBurstSize()) { |
| throw new IllegalArgumentException("RTT burst size is out of range"); |
| } |
| } |
| |
| /** |
| * Builder class used to construct {@link RangingRequest} objects. |
| */ |
| public static final class Builder { |
| private List<ResponderConfig> mRttPeers = new ArrayList<>(); |
| private int mRttBurstSize = DEFAULT_RTT_BURST_SIZE; |
| |
| /** |
| * Set the RTT Burst size for the ranging request. |
| * <p> |
| * If not set, the default RTT burst size given by |
| * {@link #getDefaultRttBurstSize()} is used to determine the default value. |
| * If set, the value must be in the range {@link #getMinRttBurstSize()} and |
| * {@link #getMaxRttBurstSize()} inclusively, or a |
| * {@link java.lang.IllegalArgumentException} will be thrown. |
| * |
| * @param rttBurstSize The number of FTM packets used to estimate a range. |
| * @return The builder to facilitate chaining |
| * {@code builder.setXXX(..).setXXX(..)}. |
| */ |
| @NonNull |
| public Builder setRttBurstSize(int rttBurstSize) { |
| if (rttBurstSize < MIN_RTT_BURST_SIZE || rttBurstSize > MAX_RTT_BURST_SIZE) { |
| throw new IllegalArgumentException("RTT burst size out of range."); |
| } |
| mRttBurstSize = rttBurstSize; |
| return this; |
| } |
| |
| /** |
| * Add the device specified by the {@link ScanResult} to the list of devices with |
| * which to measure range. The total number of peers added to a request cannot exceed the |
| * limit specified by {@link #getMaxPeers()}. |
| * <p> |
| * Ranging will only be supported if the Access Point supports IEEE 802.11mc, also known as |
| * two-sided RTT. Use {@link ScanResult#is80211mcResponder()} to verify the Access Point's |
| * capabilities. If not supported the result status will be |
| * {@link RangingResult#STATUS_RESPONDER_DOES_NOT_SUPPORT_IEEE80211MC}. |
| * |
| * @param apInfo Information of an Access Point (AP) obtained in a Scan Result. |
| * @return The builder to facilitate chaining |
| * {@code builder.setXXX(..).setXXX(..)}. |
| */ |
| public Builder addAccessPoint(@NonNull ScanResult apInfo) { |
| if (apInfo == null) { |
| throw new IllegalArgumentException("Null ScanResult!"); |
| } |
| return addResponder(ResponderConfig.fromScanResult(apInfo)); |
| } |
| |
| /** |
| * Add the devices specified by the {@link ScanResult}s to the list of devices with |
| * which to measure range. The total number of peers added to a request cannot exceed the |
| * limit specified by {@link #getMaxPeers()}. |
| * <p> |
| * Ranging will only be supported if the Access Point supports IEEE 802.11mc, also known as |
| * two-sided RTT. Use {@link ScanResult#is80211mcResponder()} to verify the Access Point's |
| * capabilities. If not supported, the result status will be |
| * {@link RangingResult#STATUS_RESPONDER_DOES_NOT_SUPPORT_IEEE80211MC}. |
| * |
| * @param apInfos Information of an Access Points (APs) obtained in a Scan Result. |
| * @return The builder to facilitate chaining |
| * {@code builder.setXXX(..).setXXX(..)}. |
| */ |
| public Builder addAccessPoints(@NonNull List<ScanResult> apInfos) { |
| if (apInfos == null) { |
| throw new IllegalArgumentException("Null list of ScanResults!"); |
| } |
| for (ScanResult scanResult : apInfos) { |
| addAccessPoint(scanResult); |
| } |
| return this; |
| } |
| |
| /** |
| * Add the non-802.11mc capable device specified by the {@link ScanResult} to the list of |
| * devices with which to measure range. The total number of peers added to a request cannot |
| * exceed the limit specified by {@link #getMaxPeers()}. |
| * <p> |
| * Accurate ranging cannot be supported if the Access Point does not support IEEE 802.11mc, |
| * and instead an alternate protocol called one-sided RTT will be used with lower |
| * accuracy. Use {@link ScanResult#is80211mcResponder()} to verify the Access Point)s) are |
| * not 802.11mc capable. |
| * <p> |
| * One-sided RTT does not subtract the RTT turnaround time at the Access Point, which can |
| * add hundreds of meters to the estimate. With experimentation it is possible to use this |
| * information to make a statistical estimate of the range by taking multiple measurements |
| * to several Access Points and normalizing the result. For some applications this can be |
| * used to improve range estimates based on Receive Signal Strength Indication (RSSI), but |
| * will not be as accurate as IEEE 802.11mc (two-sided RTT). |
| * <p> |
| * Note: one-sided RTT should only be used if you are very familiar with statistical |
| * estimation techniques. |
| * |
| * @param apInfo Information of an Access Point (AP) obtained in a Scan Result. |
| * @return The builder to facilitate chaining |
| * {@code builder.setXXX(..).setXXX(..)}. |
| */ |
| @NonNull |
| public Builder addNon80211mcCapableAccessPoint(@NonNull ScanResult apInfo) { |
| if (apInfo == null) { |
| throw new IllegalArgumentException("Null ScanResult!"); |
| } |
| if (apInfo.is80211mcResponder()) { |
| throw new IllegalArgumentException("AP supports the 802.11mc protocol."); |
| } |
| return addResponder(ResponderConfig.fromScanResult(apInfo)); |
| } |
| |
| /** |
| * Add the non-802.11mc capable devices specified by the {@link ScanResult} to the list of |
| * devices with which to measure range. The total number of peers added to a request cannot |
| * exceed the limit specified by {@link #getMaxPeers()}. |
| * <p> |
| * Accurate ranging cannot be supported if the Access Point does not support IEEE 802.11mc, |
| * and instead an alternate protocol called one-sided RTT will be used with lower |
| * accuracy. Use {@link ScanResult#is80211mcResponder()} to verify the Access Point)s) are |
| * not 802.11mc capable. |
| * <p> |
| * One-sided RTT does not subtract the RTT turnaround time at the Access Point, which can |
| * add hundreds of meters to the estimate. With experimentation it is possible to use this |
| * information to make a statistical estimate of the range by taking multiple measurements |
| * to several Access Points and normalizing the result. For some applications this can be |
| * used to improve range estimates based on Receive Signal Strength Indication (RSSI), but |
| * will not be as accurate as IEEE 802.11mc (two-sided RTT). |
| * <p> |
| * Note: one-sided RTT should only be used if you are very familiar with statistical |
| * estimation techniques. |
| * |
| * @param apInfos Information of an Access Points (APs) obtained in a Scan Result. |
| * @return The builder to facilitate chaining |
| * {@code builder.setXXX(..).setXXX(..)}. |
| */ |
| @NonNull |
| public Builder addNon80211mcCapableAccessPoints(@NonNull List<ScanResult> apInfos) { |
| if (apInfos == null) { |
| throw new IllegalArgumentException("Null list of ScanResults!"); |
| } |
| for (ScanResult scanResult : apInfos) { |
| if (scanResult.is80211mcResponder()) { |
| throw new IllegalArgumentException( |
| "At least one AP supports the 802.11mc protocol."); |
| } |
| addAccessPoint(scanResult); |
| } |
| return this; |
| } |
| |
| /** |
| * Add the device specified by the {@code peerMacAddress} to the list of devices with |
| * which to measure range. |
| * <p> |
| * The MAC address may be obtained out-of-band from a peer Wi-Fi Aware device. A Wi-Fi |
| * Aware device may obtain its MAC address using the {@link IdentityChangedListener} |
| * provided to |
| * {@link WifiAwareManager#attach(AttachCallback, IdentityChangedListener, Handler)}. |
| * <p> |
| * Note: in order to use this API the device must support Wi-Fi Aware |
| * {@link android.net.wifi.aware}. The peer device which is being ranged to must be |
| * configured to publish a service (with any name) with: |
| * <li>Type {@link android.net.wifi.aware.PublishConfig#PUBLISH_TYPE_UNSOLICITED}. |
| * <li>Ranging enabled |
| * {@link android.net.wifi.aware.PublishConfig.Builder#setRangingEnabled(boolean)}. |
| * |
| * @param peerMacAddress The MAC address of the Wi-Fi Aware peer. |
| * @return The builder, to facilitate chaining {@code builder.setXXX(..).setXXX(..)}. |
| */ |
| public Builder addWifiAwarePeer(@NonNull MacAddress peerMacAddress) { |
| if (peerMacAddress == null) { |
| throw new IllegalArgumentException("Null peer MAC address"); |
| } |
| return addResponder( |
| ResponderConfig.fromWifiAwarePeerMacAddressWithDefaults(peerMacAddress)); |
| } |
| |
| /** |
| * Add a device specified by a {@link PeerHandle} to the list of devices with which to |
| * measure range. |
| * <p> |
| * The {@link PeerHandle} may be obtained as part of the Wi-Fi Aware discovery process. E.g. |
| * using {@link DiscoverySessionCallback#onServiceDiscovered(PeerHandle, byte[], List)}. |
| * <p> |
| * Note: in order to use this API the device must support Wi-Fi Aware |
| * {@link android.net.wifi.aware}. The requesting device can be either publisher or |
| * subscriber in a discovery session. For both requesting device and peer device ranging |
| * must be enabled on the discovery session: |
| * <li>{@link android.net.wifi.aware.PublishConfig.Builder#setRangingEnabled(boolean)} for |
| * publisher.</li> |
| * <li>Either {@link android.net.wifi.aware.SubscribeConfig.Builder#setMinDistanceMm(int)} |
| * or {@link android.net.wifi.aware.SubscribeConfig.Builder#setMaxDistanceMm(int)} must be |
| * set to enable ranging on subscriber </li> |
| * |
| * @param peerHandle The peer handler of the peer Wi-Fi Aware device. |
| * @return The builder, to facilitate chaining {@code builder.setXXX(..).setXXX(..)}. |
| */ |
| public Builder addWifiAwarePeer(@NonNull PeerHandle peerHandle) { |
| if (peerHandle == null) { |
| throw new IllegalArgumentException("Null peer handler (identifier)"); |
| } |
| |
| return addResponder(ResponderConfig.fromWifiAwarePeerHandleWithDefaults(peerHandle)); |
| } |
| |
| /** |
| * Add the Responder device specified by the {@link ResponderConfig} to the list of devices |
| * with which to measure range. The total number of peers added to the request cannot exceed |
| * the limit specified by {@link #getMaxPeers()}. |
| * |
| * @param responder Information on the RTT Responder. |
| * @return The builder, to facilitate chaining {@code builder.setXXX(..).setXXX(..)}. |
| * |
| * @hide |
| */ |
| @SystemApi |
| public Builder addResponder(@NonNull ResponderConfig responder) { |
| if (responder == null) { |
| throw new IllegalArgumentException("Null Responder!"); |
| } |
| |
| mRttPeers.add(responder); |
| return this; |
| } |
| |
| /** |
| * Build {@link RangingRequest} given the current configurations made on the |
| * builder. |
| */ |
| public RangingRequest build() { |
| return new RangingRequest(mRttPeers, mRttBurstSize); |
| } |
| } |
| |
| @Override |
| public boolean equals(@Nullable Object o) { |
| if (this == o) { |
| return true; |
| } |
| |
| if (!(o instanceof RangingRequest)) { |
| return false; |
| } |
| |
| RangingRequest lhs = (RangingRequest) o; |
| |
| return mRttPeers.size() == lhs.mRttPeers.size() |
| && mRttPeers.containsAll(lhs.mRttPeers) |
| && mRttBurstSize == lhs.mRttBurstSize; |
| } |
| |
| @Override |
| public int hashCode() { |
| return Objects.hash(mRttPeers, mRttBurstSize); |
| } |
| } |
