src/java/android/net/ipsec/ike/ChildSessionParams.java - platform/packages/modules/IPsec - Git at Google

 /*
  * 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.ipsec.ike;

 import android.annotation.IntRange;
 import android.annotation.NonNull;
 import android.annotation.SuppressLint;
 import android.net.InetAddresses;
 import android.os.PersistableBundle;

 import com.android.server.vcn.util.PersistableBundleUtils;

 import java.net.InetAddress;
 import java.util.Arrays;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Objects;
 import java.util.concurrent.TimeUnit;

 /**
  * ChildSessionParams is an abstract class that represents proposed configurations for negotiating a
  * Child Session.
  *
  * <p>Note that references to negotiated configurations will be held, and the same parameters will
  * be reused during rekey. This includes SA Proposals, lifetimes and traffic selectors.
  *
  * <p>IKE library will send out KE payload only if user has configured one or more DH groups. The KE
  * payload in a request will use the first DH group from the first user provided SA proposal (or the
  * peer selected SA proposal if it's a rekey request). The KE payload in a response will depend on
  * the SA proposal negotiation result.
  *
  * <p>When requesting the first Child Session in IKE AUTH, IKE library will not propose any DH group
  * even if user has configured it, as per RFC 7296. When rekeying this child session, IKE library
  * will accept DH groups that are configured in its ChildSessionParams. If after rekeying user needs
  * to have the same DH group as that of the IKE Session, then they need to explicitly set the same
  * DH Group in ChildSessionParams.
  *
  * <p>@see {@link TunnelModeChildSessionParams} and {@link TransportModeChildSessionParams}
  */
 public abstract class ChildSessionParams {
     /** @hide */
     protected static final int CHILD_HARD_LIFETIME_SEC_MINIMUM = 300; // 5 minutes
     /** @hide */
     protected static final int CHILD_HARD_LIFETIME_SEC_MAXIMUM = 14400; // 4 hours
     /** @hide */
     protected static final int CHILD_HARD_LIFETIME_SEC_DEFAULT = 7200; // 2 hours

     /** @hide */
     protected static final int CHILD_SOFT_LIFETIME_SEC_MINIMUM = 120; // 2 minutes
     /** @hide */
     protected static final int CHILD_SOFT_LIFETIME_SEC_DEFAULT = 3600; // 1 hour

     /** @hide */
     protected static final int CHILD_LIFETIME_MARGIN_SEC_MINIMUM =
             (int) TimeUnit.MINUTES.toSeconds(1L);

     @NonNull private static final IkeTrafficSelector DEFAULT_TRAFFIC_SELECTOR_IPV4;
     @NonNull private static final IkeTrafficSelector DEFAULT_TRAFFIC_SELECTOR_IPV6;

     static {
         DEFAULT_TRAFFIC_SELECTOR_IPV4 =
                 buildDefaultTrafficSelector(
                         IkeTrafficSelector.TRAFFIC_SELECTOR_TYPE_IPV4_ADDR_RANGE);
         DEFAULT_TRAFFIC_SELECTOR_IPV6 =
                 buildDefaultTrafficSelector(
                         IkeTrafficSelector.TRAFFIC_SELECTOR_TYPE_IPV6_ADDR_RANGE);
     }

     private static final String IS_TRANPORT_KEY = "mIsTransport";
     /** @hide */
     protected static final String INBOUND_TS_KEY = "mInboundTrafficSelectors";
     /** @hide */
     protected static final String OUTBOUND_TS_KEY = "mOutboundTrafficSelectors";
     /** @hide */
     protected static final String SA_PROPOSALS_KEY = "mSaProposals";
     /** @hide */
     protected static final String HARD_LIFETIME_SEC_KEY = "mHardLifetimeSec";
     /** @hide */
     protected static final String SOFT_LIFETIME_SEC_KEY = "mSoftLifetimeSec";

     @NonNull private final IkeTrafficSelector[] mInboundTrafficSelectors;
     @NonNull private final IkeTrafficSelector[] mOutboundTrafficSelectors;
     @NonNull private final ChildSaProposal[] mSaProposals;

     private final int mHardLifetimeSec;
     private final int mSoftLifetimeSec;

     private final boolean mIsTransport;

     /** @hide */
     protected ChildSessionParams(
             IkeTrafficSelector[] inboundTs,
             IkeTrafficSelector[] outboundTs,
             ChildSaProposal[] proposals,
             int hardLifetimeSec,
             int softLifetimeSec,
             boolean isTransport) {
         mInboundTrafficSelectors = inboundTs;
         mOutboundTrafficSelectors = outboundTs;
         mSaProposals = proposals;
         mHardLifetimeSec = hardLifetimeSec;
         mSoftLifetimeSec = softLifetimeSec;
         mIsTransport = isTransport;
     }

     /**
      * Constructs this object by deserializing a PersistableBundle
      *
      * @hide
      */
     @NonNull
     public static ChildSessionParams fromPersistableBundle(@NonNull PersistableBundle in) {
         Objects.requireNonNull(in, "PersistableBundle is null");

         if (in.getBoolean(IS_TRANPORT_KEY)) {
             return TransportModeChildSessionParams.fromPersistableBundle(in);
         } else {
             return TunnelModeChildSessionParams.fromPersistableBundle(in);
         }
     }

     /**
      * Serializes this object to a PersistableBundle
      *
      * @hide
      */
     @NonNull
     public PersistableBundle toPersistableBundle() {
         final PersistableBundle result = new PersistableBundle();

         result.putBoolean(IS_TRANPORT_KEY, mIsTransport);

         PersistableBundle saProposalBundle =
                 PersistableBundleUtils.fromList(
                         Arrays.asList(mSaProposals), ChildSaProposal::toPersistableBundle);
         result.putPersistableBundle(SA_PROPOSALS_KEY, saProposalBundle);

         PersistableBundle inTsBundle =
                 PersistableBundleUtils.fromList(
                         Arrays.asList(mInboundTrafficSelectors),
                         IkeTrafficSelector::toPersistableBundle);
         result.putPersistableBundle(INBOUND_TS_KEY, inTsBundle);

         PersistableBundle outTsBundle =
                 PersistableBundleUtils.fromList(
                         Arrays.asList(mOutboundTrafficSelectors),
                         IkeTrafficSelector::toPersistableBundle);
         result.putPersistableBundle(OUTBOUND_TS_KEY, outTsBundle);

         result.putInt(HARD_LIFETIME_SEC_KEY, mHardLifetimeSec);
         result.putInt(SOFT_LIFETIME_SEC_KEY, mSoftLifetimeSec);
         return result;
     }

     /** @hide */
     protected static List<ChildSaProposal> getProposalsFromPersistableBundle(PersistableBundle in) {
         PersistableBundle proposalBundle = in.getPersistableBundle(SA_PROPOSALS_KEY);
         Objects.requireNonNull(proposalBundle, "Value for key " + SA_PROPOSALS_KEY + " was null");
         return PersistableBundleUtils.toList(
                 proposalBundle, ChildSaProposal::fromPersistableBundle);
     }

     /** @hide */
     protected static List<IkeTrafficSelector> getTsFromPersistableBundle(
             PersistableBundle in, String key) {
         PersistableBundle tsBundle = in.getPersistableBundle(key);
         Objects.requireNonNull(tsBundle, "Value for key " + key + " was null");
         return PersistableBundleUtils.toList(tsBundle, IkeTrafficSelector::fromPersistableBundle);
     }

     /**
      * Retrieves configured inbound traffic selectors
      *
      * <p>@see {@link
      * TunnelModeChildSessionParams.Builder#addInboundTrafficSelectors(IkeTrafficSelector)} or
      * {@link
      * TransportModeChildSessionParams.Builder#addInboundTrafficSelectors(IkeTrafficSelector)}
      */
     @NonNull
     public List<IkeTrafficSelector> getInboundTrafficSelectors() {
         return Arrays.asList(mInboundTrafficSelectors);
     }

     /**
      * Retrieves configured outbound traffic selectors
      *
      * <p>@see {@link
      * TunnelModeChildSessionParams.Builder#addOutboundTrafficSelectors(IkeTrafficSelector)} or
      * {@link
      * TransportModeChildSessionParams.Builder#addOutboundTrafficSelectors(IkeTrafficSelector)}
      */
     @NonNull
     public List<IkeTrafficSelector> getOutboundTrafficSelectors() {
         return Arrays.asList(mOutboundTrafficSelectors);
     }

     /** Retrieves all ChildSaProposals configured */
     @NonNull
     public List<ChildSaProposal> getSaProposals() {
         return Arrays.asList(mSaProposals);
     }

     /** Retrieves hard lifetime in seconds */
     // Use "second" because smaller unit won't make sense to describe a rekey interval.
     @SuppressLint("MethodNameUnits")
     @IntRange(from = CHILD_HARD_LIFETIME_SEC_MINIMUM, to = CHILD_HARD_LIFETIME_SEC_MAXIMUM)
     public int getHardLifetimeSeconds() {
         return mHardLifetimeSec;
     }

     /** Retrieves soft lifetime in seconds */
     // Use "second" because smaller unit won't make sense to describe a rekey interval.
     @SuppressLint("MethodNameUnits")
     @IntRange(from = CHILD_SOFT_LIFETIME_SEC_MINIMUM, to = CHILD_HARD_LIFETIME_SEC_MAXIMUM)
     public int getSoftLifetimeSeconds() {
         return mSoftLifetimeSec;
     }

     /** @hide */
     public IkeTrafficSelector[] getInboundTrafficSelectorsInternal() {
         return mInboundTrafficSelectors;
     }

     /** @hide */
     public IkeTrafficSelector[] getOutboundTrafficSelectorsInternal() {
         return mOutboundTrafficSelectors;
     }

     /** @hide */
     public ChildSaProposal[] getSaProposalsInternal() {
         return mSaProposals;
     }

     /** @hide */
     public long getHardLifetimeMsInternal() {
         return TimeUnit.SECONDS.toMillis((long) mHardLifetimeSec);
     }

     /** @hide */
     public long getSoftLifetimeMsInternal() {
         return TimeUnit.SECONDS.toMillis((long) mSoftLifetimeSec);
     }

     /** @hide */
     public boolean isTransportMode() {
         return mIsTransport;
     }

     @Override
     public int hashCode() {
         return Objects.hash(
                 Arrays.hashCode(mInboundTrafficSelectors),
                 Arrays.hashCode(mOutboundTrafficSelectors),
                 Arrays.hashCode(mSaProposals),
                 mHardLifetimeSec,
                 mSoftLifetimeSec,
                 mIsTransport);
     }

     @Override
     public boolean equals(Object o) {
         if (!(o instanceof ChildSessionParams)) {
             return false;
         }

         ChildSessionParams other = (ChildSessionParams) o;

         return Arrays.equals(mInboundTrafficSelectors, other.mInboundTrafficSelectors)
                 && Arrays.equals(mOutboundTrafficSelectors, other.mOutboundTrafficSelectors)
                 && Arrays.equals(mSaProposals, other.mSaProposals)
                 && mHardLifetimeSec == other.mHardLifetimeSec
                 && mSoftLifetimeSec == other.mSoftLifetimeSec
                 && mIsTransport == other.mIsTransport;
     }

     /**
      * This class represents common information for Child Session Parameters Builders.
      *
      * @hide
      */
     protected abstract static class Builder {
         @NonNull protected final List<IkeTrafficSelector> mInboundTsList = new LinkedList<>();
         @NonNull protected final List<IkeTrafficSelector> mOutboundTsList = new LinkedList<>();
         @NonNull protected final List<SaProposal> mSaProposalList = new LinkedList<>();

         protected int mHardLifetimeSec = CHILD_HARD_LIFETIME_SEC_DEFAULT;
         protected int mSoftLifetimeSec = CHILD_SOFT_LIFETIME_SEC_DEFAULT;

         /** Package private constructor */
         Builder() {}

         /** Package private constructor */
         Builder(@NonNull ChildSessionParams childParams) {
             Objects.requireNonNull(childParams, "childParams was null");

             mInboundTsList.addAll(childParams.getInboundTrafficSelectors());
             mOutboundTsList.addAll(childParams.getOutboundTrafficSelectors());
             mSaProposalList.addAll(childParams.getSaProposals());
             mHardLifetimeSec = childParams.getHardLifetimeSeconds();
             mSoftLifetimeSec = childParams.getSoftLifetimeSeconds();
         }

         protected void addProposal(@NonNull ChildSaProposal proposal) {
             mSaProposalList.add(proposal);
         }

         protected void addInboundTs(@NonNull IkeTrafficSelector trafficSelector) {
             mInboundTsList.add(trafficSelector);
         }

         protected void addOutboundTs(@NonNull IkeTrafficSelector trafficSelector) {
             mOutboundTsList.add(trafficSelector);
         }

         protected void validateAndSetLifetime(int hardLifetimeSec, int softLifetimeSec) {
             if (hardLifetimeSec < CHILD_HARD_LIFETIME_SEC_MINIMUM
                     || hardLifetimeSec > CHILD_HARD_LIFETIME_SEC_MAXIMUM
                     || softLifetimeSec < CHILD_SOFT_LIFETIME_SEC_MINIMUM
                     || hardLifetimeSec - softLifetimeSec < CHILD_LIFETIME_MARGIN_SEC_MINIMUM) {
                 throw new IllegalArgumentException("Invalid lifetime value");
             }
         }

         protected void validateOrThrow() {
             if (mSaProposalList.isEmpty()) {
                 throw new IllegalArgumentException(
                         "ChildSessionParams requires at least one Child SA proposal.");
             }
         }

         protected void addDefaultTsIfNotConfigured() {
             if (mInboundTsList.isEmpty()) {
                 mInboundTsList.add(DEFAULT_TRAFFIC_SELECTOR_IPV4);
                 mInboundTsList.add(DEFAULT_TRAFFIC_SELECTOR_IPV6);
             }

             if (mOutboundTsList.isEmpty()) {
                 mOutboundTsList.add(DEFAULT_TRAFFIC_SELECTOR_IPV4);
                 mOutboundTsList.add(DEFAULT_TRAFFIC_SELECTOR_IPV6);
             }
         }
     }

     private static IkeTrafficSelector buildDefaultTrafficSelector(
             @IkeTrafficSelector.TrafficSelectorType int tsType) {
         int startPort = IkeTrafficSelector.PORT_NUMBER_MIN;
         int endPort = IkeTrafficSelector.PORT_NUMBER_MAX;
         InetAddress startAddress = null;
         InetAddress endAddress = null;
         switch (tsType) {
             case IkeTrafficSelector.TRAFFIC_SELECTOR_TYPE_IPV4_ADDR_RANGE:
                 startAddress = InetAddresses.parseNumericAddress("0.0.0.0");
                 endAddress = InetAddresses.parseNumericAddress("255.255.255.255");
                 break;
             case IkeTrafficSelector.TRAFFIC_SELECTOR_TYPE_IPV6_ADDR_RANGE:
                 startAddress = InetAddresses.parseNumericAddress("::");
                 endAddress =
                         InetAddresses.parseNumericAddress(
                                 "ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff");
                 break;
             default:
                 throw new IllegalArgumentException("Invalid Traffic Selector type: " + tsType);
         }

         return new IkeTrafficSelector(tsType, startPort, endPort, startAddress, endAddress);
     }
 }
	/*
	* 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.ipsec.ike;

	import android.annotation.IntRange;
	import android.annotation.NonNull;
	import android.annotation.SuppressLint;
	import android.net.InetAddresses;
	import android.os.PersistableBundle;

	import com.android.server.vcn.util.PersistableBundleUtils;

	import java.net.InetAddress;
	import java.util.Arrays;
	import java.util.LinkedList;
	import java.util.List;
	import java.util.Objects;
	import java.util.concurrent.TimeUnit;

	/**
	* ChildSessionParams is an abstract class that represents proposed configurations for negotiating a
	* Child Session.
	*
	* <p>Note that references to negotiated configurations will be held, and the same parameters will
	* be reused during rekey. This includes SA Proposals, lifetimes and traffic selectors.
	*
	* <p>IKE library will send out KE payload only if user has configured one or more DH groups. The KE
	* payload in a request will use the first DH group from the first user provided SA proposal (or the
	* peer selected SA proposal if it's a rekey request). The KE payload in a response will depend on
	* the SA proposal negotiation result.
	*
	* <p>When requesting the first Child Session in IKE AUTH, IKE library will not propose any DH group
	* even if user has configured it, as per RFC 7296. When rekeying this child session, IKE library
	* will accept DH groups that are configured in its ChildSessionParams. If after rekeying user needs
	* to have the same DH group as that of the IKE Session, then they need to explicitly set the same
	* DH Group in ChildSessionParams.
	*
	* <p>@see {@link TunnelModeChildSessionParams} and {@link TransportModeChildSessionParams}
	*/
	public abstract class ChildSessionParams {
	/** @hide */
	protected static final int CHILD_HARD_LIFETIME_SEC_MINIMUM = 300; // 5 minutes
	/** @hide */
	protected static final int CHILD_HARD_LIFETIME_SEC_MAXIMUM = 14400; // 4 hours
	/** @hide */
	protected static final int CHILD_HARD_LIFETIME_SEC_DEFAULT = 7200; // 2 hours

	/** @hide */
	protected static final int CHILD_SOFT_LIFETIME_SEC_MINIMUM = 120; // 2 minutes
	/** @hide */
	protected static final int CHILD_SOFT_LIFETIME_SEC_DEFAULT = 3600; // 1 hour

	/** @hide */
	protected static final int CHILD_LIFETIME_MARGIN_SEC_MINIMUM =
	(int) TimeUnit.MINUTES.toSeconds(1L);

	@NonNull private static final IkeTrafficSelector DEFAULT_TRAFFIC_SELECTOR_IPV4;
	@NonNull private static final IkeTrafficSelector DEFAULT_TRAFFIC_SELECTOR_IPV6;

	static {
	DEFAULT_TRAFFIC_SELECTOR_IPV4 =
	buildDefaultTrafficSelector(
	IkeTrafficSelector.TRAFFIC_SELECTOR_TYPE_IPV4_ADDR_RANGE);
	DEFAULT_TRAFFIC_SELECTOR_IPV6 =
	buildDefaultTrafficSelector(
	IkeTrafficSelector.TRAFFIC_SELECTOR_TYPE_IPV6_ADDR_RANGE);
	}

	private static final String IS_TRANPORT_KEY = "mIsTransport";
	/** @hide */
	protected static final String INBOUND_TS_KEY = "mInboundTrafficSelectors";
	/** @hide */
	protected static final String OUTBOUND_TS_KEY = "mOutboundTrafficSelectors";
	/** @hide */
	protected static final String SA_PROPOSALS_KEY = "mSaProposals";
	/** @hide */
	protected static final String HARD_LIFETIME_SEC_KEY = "mHardLifetimeSec";
	/** @hide */
	protected static final String SOFT_LIFETIME_SEC_KEY = "mSoftLifetimeSec";

	@NonNull private final IkeTrafficSelector[] mInboundTrafficSelectors;
	@NonNull private final IkeTrafficSelector[] mOutboundTrafficSelectors;
	@NonNull private final ChildSaProposal[] mSaProposals;

	private final int mHardLifetimeSec;
	private final int mSoftLifetimeSec;

	private final boolean mIsTransport;

	/** @hide */
	protected ChildSessionParams(
	IkeTrafficSelector[] inboundTs,
	IkeTrafficSelector[] outboundTs,
	ChildSaProposal[] proposals,
	int hardLifetimeSec,
	int softLifetimeSec,
	boolean isTransport) {
	mInboundTrafficSelectors = inboundTs;
	mOutboundTrafficSelectors = outboundTs;
	mSaProposals = proposals;
	mHardLifetimeSec = hardLifetimeSec;
	mSoftLifetimeSec = softLifetimeSec;
	mIsTransport = isTransport;
	}

	/**
	* Constructs this object by deserializing a PersistableBundle
	*
	* @hide
	*/
	@NonNull
	public static ChildSessionParams fromPersistableBundle(@NonNull PersistableBundle in) {
	Objects.requireNonNull(in, "PersistableBundle is null");

	if (in.getBoolean(IS_TRANPORT_KEY)) {
	return TransportModeChildSessionParams.fromPersistableBundle(in);
	} else {
	return TunnelModeChildSessionParams.fromPersistableBundle(in);
	}
	}

	/**
	* Serializes this object to a PersistableBundle
	*
	* @hide
	*/
	@NonNull
	public PersistableBundle toPersistableBundle() {
	final PersistableBundle result = new PersistableBundle();

	result.putBoolean(IS_TRANPORT_KEY, mIsTransport);

	PersistableBundle saProposalBundle =
	PersistableBundleUtils.fromList(
	Arrays.asList(mSaProposals), ChildSaProposal::toPersistableBundle);
	result.putPersistableBundle(SA_PROPOSALS_KEY, saProposalBundle);

	PersistableBundle inTsBundle =
	PersistableBundleUtils.fromList(
	Arrays.asList(mInboundTrafficSelectors),
	IkeTrafficSelector::toPersistableBundle);
	result.putPersistableBundle(INBOUND_TS_KEY, inTsBundle);

	PersistableBundle outTsBundle =
	PersistableBundleUtils.fromList(
	Arrays.asList(mOutboundTrafficSelectors),
	IkeTrafficSelector::toPersistableBundle);
	result.putPersistableBundle(OUTBOUND_TS_KEY, outTsBundle);

	result.putInt(HARD_LIFETIME_SEC_KEY, mHardLifetimeSec);
	result.putInt(SOFT_LIFETIME_SEC_KEY, mSoftLifetimeSec);
	return result;
	}

	/** @hide */
	protected static List<ChildSaProposal> getProposalsFromPersistableBundle(PersistableBundle in) {
	PersistableBundle proposalBundle = in.getPersistableBundle(SA_PROPOSALS_KEY);
	Objects.requireNonNull(proposalBundle, "Value for key " + SA_PROPOSALS_KEY + " was null");
	return PersistableBundleUtils.toList(
	proposalBundle, ChildSaProposal::fromPersistableBundle);
	}

	/** @hide */
	protected static List<IkeTrafficSelector> getTsFromPersistableBundle(
	PersistableBundle in, String key) {
	PersistableBundle tsBundle = in.getPersistableBundle(key);
	Objects.requireNonNull(tsBundle, "Value for key " + key + " was null");
	return PersistableBundleUtils.toList(tsBundle, IkeTrafficSelector::fromPersistableBundle);
	}

	/**
	* Retrieves configured inbound traffic selectors
	*
	* <p>@see {@link
	* TunnelModeChildSessionParams.Builder#addInboundTrafficSelectors(IkeTrafficSelector)} or
	* {@link
	* TransportModeChildSessionParams.Builder#addInboundTrafficSelectors(IkeTrafficSelector)}
	*/
	@NonNull
	public List<IkeTrafficSelector> getInboundTrafficSelectors() {
	return Arrays.asList(mInboundTrafficSelectors);
	}

	/**
	* Retrieves configured outbound traffic selectors
	*
	* <p>@see {@link
	* TunnelModeChildSessionParams.Builder#addOutboundTrafficSelectors(IkeTrafficSelector)} or
	* {@link
	* TransportModeChildSessionParams.Builder#addOutboundTrafficSelectors(IkeTrafficSelector)}
	*/
	@NonNull
	public List<IkeTrafficSelector> getOutboundTrafficSelectors() {
	return Arrays.asList(mOutboundTrafficSelectors);
	}

	/** Retrieves all ChildSaProposals configured */
	@NonNull
	public List<ChildSaProposal> getSaProposals() {
	return Arrays.asList(mSaProposals);
	}

	/** Retrieves hard lifetime in seconds */
	// Use "second" because smaller unit won't make sense to describe a rekey interval.
	@SuppressLint("MethodNameUnits")
	@IntRange(from = CHILD_HARD_LIFETIME_SEC_MINIMUM, to = CHILD_HARD_LIFETIME_SEC_MAXIMUM)
	public int getHardLifetimeSeconds() {
	return mHardLifetimeSec;
	}

	/** Retrieves soft lifetime in seconds */
	// Use "second" because smaller unit won't make sense to describe a rekey interval.
	@SuppressLint("MethodNameUnits")
	@IntRange(from = CHILD_SOFT_LIFETIME_SEC_MINIMUM, to = CHILD_HARD_LIFETIME_SEC_MAXIMUM)
	public int getSoftLifetimeSeconds() {
	return mSoftLifetimeSec;
	}

	/** @hide */
	public IkeTrafficSelector[] getInboundTrafficSelectorsInternal() {
	return mInboundTrafficSelectors;
	}

	/** @hide */
	public IkeTrafficSelector[] getOutboundTrafficSelectorsInternal() {
	return mOutboundTrafficSelectors;
	}

	/** @hide */
	public ChildSaProposal[] getSaProposalsInternal() {
	return mSaProposals;
	}

	/** @hide */
	public long getHardLifetimeMsInternal() {
	return TimeUnit.SECONDS.toMillis((long) mHardLifetimeSec);
	}

	/** @hide */
	public long getSoftLifetimeMsInternal() {
	return TimeUnit.SECONDS.toMillis((long) mSoftLifetimeSec);
	}

	/** @hide */
	public boolean isTransportMode() {
	return mIsTransport;
	}

	@Override
	public int hashCode() {
	return Objects.hash(
	Arrays.hashCode(mInboundTrafficSelectors),
	Arrays.hashCode(mOutboundTrafficSelectors),
	Arrays.hashCode(mSaProposals),
	mHardLifetimeSec,
	mSoftLifetimeSec,
	mIsTransport);
	}

	@Override
	public boolean equals(Object o) {
	if (!(o instanceof ChildSessionParams)) {
	return false;
	}

	ChildSessionParams other = (ChildSessionParams) o;

	return Arrays.equals(mInboundTrafficSelectors, other.mInboundTrafficSelectors)
	&& Arrays.equals(mOutboundTrafficSelectors, other.mOutboundTrafficSelectors)
	&& Arrays.equals(mSaProposals, other.mSaProposals)
	&& mHardLifetimeSec == other.mHardLifetimeSec
	&& mSoftLifetimeSec == other.mSoftLifetimeSec
	&& mIsTransport == other.mIsTransport;
	}

	/**
	* This class represents common information for Child Session Parameters Builders.
	*
	* @hide
	*/
	protected abstract static class Builder {
	@NonNull protected final List<IkeTrafficSelector> mInboundTsList = new LinkedList<>();
	@NonNull protected final List<IkeTrafficSelector> mOutboundTsList = new LinkedList<>();
	@NonNull protected final List<SaProposal> mSaProposalList = new LinkedList<>();

	protected int mHardLifetimeSec = CHILD_HARD_LIFETIME_SEC_DEFAULT;
	protected int mSoftLifetimeSec = CHILD_SOFT_LIFETIME_SEC_DEFAULT;

	/** Package private constructor */
	Builder() {}

	/** Package private constructor */
	Builder(@NonNull ChildSessionParams childParams) {
	Objects.requireNonNull(childParams, "childParams was null");

	mInboundTsList.addAll(childParams.getInboundTrafficSelectors());
	mOutboundTsList.addAll(childParams.getOutboundTrafficSelectors());
	mSaProposalList.addAll(childParams.getSaProposals());
	mHardLifetimeSec = childParams.getHardLifetimeSeconds();
	mSoftLifetimeSec = childParams.getSoftLifetimeSeconds();
	}

	protected void addProposal(@NonNull ChildSaProposal proposal) {
	mSaProposalList.add(proposal);
	}

	protected void addInboundTs(@NonNull IkeTrafficSelector trafficSelector) {
	mInboundTsList.add(trafficSelector);
	}

	protected void addOutboundTs(@NonNull IkeTrafficSelector trafficSelector) {
	mOutboundTsList.add(trafficSelector);
	}

	protected void validateAndSetLifetime(int hardLifetimeSec, int softLifetimeSec) {
	if (hardLifetimeSec < CHILD_HARD_LIFETIME_SEC_MINIMUM
	\|\| hardLifetimeSec > CHILD_HARD_LIFETIME_SEC_MAXIMUM
	\|\| softLifetimeSec < CHILD_SOFT_LIFETIME_SEC_MINIMUM
	\|\| hardLifetimeSec - softLifetimeSec < CHILD_LIFETIME_MARGIN_SEC_MINIMUM) {
	throw new IllegalArgumentException("Invalid lifetime value");
	}
	}

	protected void validateOrThrow() {
	if (mSaProposalList.isEmpty()) {
	throw new IllegalArgumentException(
	"ChildSessionParams requires at least one Child SA proposal.");
	}
	}

	protected void addDefaultTsIfNotConfigured() {
	if (mInboundTsList.isEmpty()) {
	mInboundTsList.add(DEFAULT_TRAFFIC_SELECTOR_IPV4);
	mInboundTsList.add(DEFAULT_TRAFFIC_SELECTOR_IPV6);
	}

	if (mOutboundTsList.isEmpty()) {
	mOutboundTsList.add(DEFAULT_TRAFFIC_SELECTOR_IPV4);
	mOutboundTsList.add(DEFAULT_TRAFFIC_SELECTOR_IPV6);
	}
	}
	}

	private static IkeTrafficSelector buildDefaultTrafficSelector(
	@IkeTrafficSelector.TrafficSelectorType int tsType) {
	int startPort = IkeTrafficSelector.PORT_NUMBER_MIN;
	int endPort = IkeTrafficSelector.PORT_NUMBER_MAX;
	InetAddress startAddress = null;
	InetAddress endAddress = null;
	switch (tsType) {
	case IkeTrafficSelector.TRAFFIC_SELECTOR_TYPE_IPV4_ADDR_RANGE:
	startAddress = InetAddresses.parseNumericAddress("0.0.0.0");
	endAddress = InetAddresses.parseNumericAddress("255.255.255.255");
	break;
	case IkeTrafficSelector.TRAFFIC_SELECTOR_TYPE_IPV6_ADDR_RANGE:
	startAddress = InetAddresses.parseNumericAddress("::");
	endAddress =
	InetAddresses.parseNumericAddress(
	"ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff");
	break;
	default:
	throw new IllegalArgumentException("Invalid Traffic Selector type: " + tsType);
	}

	return new IkeTrafficSelector(tsType, startPort, endPort, startAddress, endAddress);
	}
	}