[VCN04] Add Subscription Id set into NetworkCapabilities

This is a generic way to request networks that has different
subId but belongs to the same carrier. For example, cellular
networks with different SIM card, or carrier Wifi that
provided by the operator.

Test: atest NetworkCapabilitiesTest#testSubIds
Test: m doc-comment-check-docs -j
Test: atest CtsNetTestCases
Bug: 175662146

Change-Id: Ifca766f5acc73c285948d6251ec31506d9bb0bcb

framework/src/android/net/NetworkCapabilities.java

@@ -131,6 +131,7 @@ public final class NetworkCapabilities implements Parcelable {
         mPrivateDnsBroken = false;
         mRequestorUid = Process.INVALID_UID;
         mRequestorPackageName = null;
+        mSubIds = new ArraySet<>();
     }
 
     /**
@@ -159,6 +160,7 @@ public final class NetworkCapabilities implements Parcelable {
         mPrivateDnsBroken = nc.mPrivateDnsBroken;
         mRequestorUid = nc.mRequestorUid;
         mRequestorPackageName = nc.mRequestorPackageName;
+        mSubIds = new ArraySet<>(nc.mSubIds);
     }
 
     /**
@@ -1655,6 +1657,7 @@ public final class NetworkCapabilities implements Parcelable {
         combineSSIDs(nc);
         combineRequestor(nc);
         combineAdministratorUids(nc);
+        combineSubIds(nc);
     }
 
     /**
@@ -1674,8 +1677,9 @@ public final class NetworkCapabilities implements Parcelable {
                 && satisfiedBySpecifier(nc)
                 && (onlyImmutable || satisfiedBySignalStrength(nc))
                 && (onlyImmutable || satisfiedByUids(nc))
-                && (onlyImmutable || satisfiedBySSID(nc)))
-                && (onlyImmutable || satisfiedByRequestor(nc));
+                && (onlyImmutable || satisfiedBySSID(nc))
+                && (onlyImmutable || satisfiedByRequestor(nc))
+                && (onlyImmutable || satisfiedBySubIds(nc)));
     }
 
     /**
@@ -1771,7 +1775,8 @@ public final class NetworkCapabilities implements Parcelable {
                 && equalsOwnerUid(that)
                 && equalsPrivateDnsBroken(that)
                 && equalsRequestor(that)
-                && equalsAdministratorUids(that);
+                && equalsAdministratorUids(that)
+                && equalsSubIds(that);
     }
 
     @Override
@@ -1793,7 +1798,8 @@ public final class NetworkCapabilities implements Parcelable {
                 + Objects.hashCode(mPrivateDnsBroken) * 47
                 + Objects.hashCode(mRequestorUid) * 53
                 + Objects.hashCode(mRequestorPackageName) * 59
-                + Arrays.hashCode(mAdministratorUids) * 61;
+                + Arrays.hashCode(mAdministratorUids) * 61
+                + Objects.hashCode(mSubIds) * 67;
     }
 
     @Override
@@ -1827,6 +1833,7 @@ public final class NetworkCapabilities implements Parcelable {
         dest.writeInt(mOwnerUid);
         dest.writeInt(mRequestorUid);
         dest.writeString(mRequestorPackageName);
+        dest.writeIntArray(CollectionUtils.toIntArray(mSubIds));
     }
 
     public static final @android.annotation.NonNull Creator<NetworkCapabilities> CREATOR =
@@ -1850,6 +1857,11 @@ public final class NetworkCapabilities implements Parcelable {
                 netCap.mOwnerUid = in.readInt();
                 netCap.mRequestorUid = in.readInt();
                 netCap.mRequestorPackageName = in.readString();
+                netCap.mSubIds = new ArraySet<>();
+                final int[] subIdInts = Objects.requireNonNull(in.createIntArray());
+                for (int i = 0; i < subIdInts.length; i++) {
+                    netCap.mSubIds.add(subIdInts[i]);
+                }
                 return netCap;
             }
             @Override
@@ -1933,11 +1945,14 @@ public final class NetworkCapabilities implements Parcelable {
             sb.append(" SSID: ").append(mSSID);
         }
 
-
         if (mPrivateDnsBroken) {
             sb.append(" PrivateDnsBroken");
         }
 
+        if (!mSubIds.isEmpty()) {
+            sb.append(" SubscriptionIds: ").append(mSubIds);
+        }
+
         sb.append("]");
         return sb.toString();
     }
@@ -2250,6 +2265,68 @@ public final class NetworkCapabilities implements Parcelable {
                 && TextUtils.equals(mRequestorPackageName, nc.mRequestorPackageName);
     }
 
+    /**
+     * Set of the subscription IDs that identifies the network or request, empty if none.
+     */
+    @NonNull
+    private ArraySet<Integer> mSubIds = new ArraySet<>();
+
+    /**
+     * Sets the subscription ID set that associated to this network or request.
+     *
+     * @hide
+     */
+    @NonNull
+    public NetworkCapabilities setSubIds(@NonNull Set<Integer> subIds) {
+        mSubIds = new ArraySet(Objects.requireNonNull(subIds));
+        return this;
+    }
+
+    /**
+     * Gets the subscription ID set that associated to this network or request.
+     * @hide
+     * @return
+     */
+    @NonNull
+    public Set<Integer> getSubIds() {
+        return new ArraySet<>(mSubIds);
+    }
+
+    /**
+     * Tests if the subscription ID set of this network is the same as that of the passed one.
+     */
+    private boolean equalsSubIds(@NonNull NetworkCapabilities nc) {
+        return Objects.equals(mSubIds, nc.mSubIds);
+    }
+
+    /**
+     * Check if the subscription ID set requirements of this object are matched by the passed one.
+     * If specified in the request, the passed one need to have at least one subId and at least
+     * one of them needs to be in the request set.
+     */
+    private boolean satisfiedBySubIds(@NonNull NetworkCapabilities nc) {
+        if (mSubIds.isEmpty()) return true;
+        if (nc.mSubIds.isEmpty()) return false;
+        for (final Integer subId : nc.mSubIds) {
+            if (mSubIds.contains(subId)) return true;
+        }
+        return false;
+    }
+
+    /**
+     * Combine subscription ID set of the capabilities.
+     *
+     * <p>This is only legal if the subscription Ids are equal.
+     *
+     * <p>If both subscription IDs are not equal, they belong to different subscription
+     * (or no subscription). In this case, it would not make sense to add them together.
+     */
+    private void combineSubIds(@NonNull NetworkCapabilities nc) {
+        if (!Objects.equals(mSubIds, nc.mSubIds)) {
+            throw new IllegalStateException("Can't combine two subscription ID sets");
+        }
+    }
+
     /**
      * Builder class for NetworkCapabilities.
      *
@@ -2555,6 +2632,20 @@ public final class NetworkCapabilities implements Parcelable {
             return this;
         }
 
+        /**
+         * Set the subscription ID set.
+         *
+         * @param subIds a set that represent the subscription IDs. Empty if clean up.
+         * @return this builder.
+         *
+         * @hide
+         */
+        @NonNull
+        public Builder setSubIds(@NonNull final Set<Integer> subIds) {
+            mCaps.setSubIds(subIds);
+            return this;
+        }
+
         /**
          * Builds the instance of the capabilities.
          *

framework/src/android/net/NetworkRequest.java

@@ -456,6 +456,23 @@ public class NetworkRequest implements Parcelable {
             }
             nc.addCapability(NET_CAPABILITY_NOT_VCN_MANAGED);
         }
+
+        /**
+         * Sets the optional subscription ID set.
+         * <p>
+         * This specify the subscription IDs requirement.
+         * A network will satisfy this request only if it matches one of the subIds in this set.
+         * An empty set matches all networks, including those without a subId.
+         *
+         * @param subIds A {@code Set} that represents subscription IDs.
+         *
+         * @hide
+         */
+        @NonNull
+        public Builder setSubIds(@NonNull Set<Integer> subIds) {
+            mNetworkCapabilities.setSubIds(subIds);
+            return this;
+        }
     }
 
     // implement the Parcelable interface