diff options
Diffstat (limited to 'core/java/android')
3 files changed, 62 insertions, 3 deletions
diff --git a/core/java/android/net/ipmemorystore/IOnNetworkAttributesRetrieved.aidl b/core/java/android/net/ipmemorystore/IOnNetworkAttributesRetrieved.aidl index 57f59a17cfe7..fb4ca3b97895 100644 --- a/core/java/android/net/ipmemorystore/IOnNetworkAttributesRetrieved.aidl +++ b/core/java/android/net/ipmemorystore/IOnNetworkAttributesRetrieved.aidl @@ -25,6 +25,6 @@ oneway interface IOnNetworkAttributesRetrieved { * Network attributes were fetched for the specified L2 key. While the L2 key will never * be null, the attributes may be if no data is stored about this L2 key. */ - void onL2KeyResponse(in StatusParcelable status, in String l2Key, + void onNetworkAttributesRetrieved(in StatusParcelable status, in String l2Key, in NetworkAttributesParcelable attributes); } diff --git a/core/java/android/net/ipmemorystore/NetworkAttributes.java b/core/java/android/net/ipmemorystore/NetworkAttributes.java index b932d2197f85..5397b57a4568 100644 --- a/core/java/android/net/ipmemorystore/NetworkAttributes.java +++ b/core/java/android/net/ipmemorystore/NetworkAttributes.java @@ -37,27 +37,57 @@ import java.util.StringJoiner; public class NetworkAttributes { private static final boolean DBG = true; + // Weight cutoff for grouping. To group, a similarity score is computed with the following + // algorithm : if both fields are non-null and equals() then add their assigned weight, else if + // both are null then add a portion of their assigned weight (see NULL_MATCH_WEIGHT), + // otherwise add nothing. + // As a guideline, this should be something like 60~75% of the total weights in this class. The + // design states "in essence a reader should imagine that if two important columns don't match, + // or one important and several unimportant columns don't match then the two records are + // considered a different group". + private static final float TOTAL_WEIGHT_CUTOFF = 520.0f; + // The portion of the weight that is earned when scoring group-sameness by having both columns + // being null. This is because some networks rightfully don't have some attributes (e.g. a + // V6-only network won't have an assigned V4 address) and both being null should count for + // something, but attributes may also be null just because data is unavailable. + private static final float NULL_MATCH_WEIGHT = 0.25f; + // The v4 address that was assigned to this device the last time it joined this network. // This typically comes from DHCP but could be something else like static configuration. // This does not apply to IPv6. // TODO : add a list of v6 prefixes for the v6 case. @Nullable public final Inet4Address assignedV4Address; + private static final float WEIGHT_ASSIGNEDV4ADDR = 300.0f; // Optionally supplied by the client if it has an opinion on L3 network. For example, this // could be a hash of the SSID + security type on WiFi. @Nullable public final String groupHint; + private static final float WEIGHT_GROUPHINT = 300.0f; // The list of DNS server addresses. @Nullable public final List<InetAddress> dnsAddresses; + private static final float WEIGHT_DNSADDRESSES = 200.0f; // The mtu on this network. @Nullable public final Integer mtu; + private static final float WEIGHT_MTU = 50.0f; + + // The sum of all weights in this class. Tests ensure that this stays equal to the total of + // all weights. + /** @hide */ + @VisibleForTesting + public static final float TOTAL_WEIGHT = WEIGHT_ASSIGNEDV4ADDR + + WEIGHT_GROUPHINT + + WEIGHT_DNSADDRESSES + + WEIGHT_MTU; - NetworkAttributes( + /** @hide */ + @VisibleForTesting + public NetworkAttributes( @Nullable final Inet4Address assignedV4Address, @Nullable final String groupHint, @Nullable final List<InetAddress> dnsAddresses, @@ -126,6 +156,34 @@ public class NetworkAttributes { return parcelable; } + private float samenessContribution(final float weight, + @Nullable final Object o1, @Nullable final Object o2) { + if (null == o1) { + return (null == o2) ? weight * NULL_MATCH_WEIGHT : 0f; + } + return Objects.equals(o1, o2) ? weight : 0f; + } + + /** @hide */ + public float getNetworkGroupSamenessConfidence(@NonNull final NetworkAttributes o) { + final float samenessScore = + samenessContribution(WEIGHT_ASSIGNEDV4ADDR, assignedV4Address, o.assignedV4Address) + + samenessContribution(WEIGHT_GROUPHINT, groupHint, o.groupHint) + + samenessContribution(WEIGHT_DNSADDRESSES, dnsAddresses, o.dnsAddresses) + + samenessContribution(WEIGHT_MTU, mtu, o.mtu); + // The minimum is 0, the max is TOTAL_WEIGHT and should be represented by 1.0, and + // TOTAL_WEIGHT_CUTOFF should represent 0.5, but there is no requirement that + // TOTAL_WEIGHT_CUTOFF would be half of TOTAL_WEIGHT (indeed, it should not be). + // So scale scores under the cutoff between 0 and 0.5, and the scores over the cutoff + // between 0.5 and 1.0. + if (samenessScore < TOTAL_WEIGHT_CUTOFF) { + return samenessScore / (TOTAL_WEIGHT_CUTOFF * 2); + } else { + return (samenessScore - TOTAL_WEIGHT_CUTOFF) / (TOTAL_WEIGHT - TOTAL_WEIGHT_CUTOFF) / 2 + + 0.5f; + } + } + /** @hide */ public static class Builder { @Nullable diff --git a/core/java/android/net/ipmemorystore/SameL3NetworkResponse.java b/core/java/android/net/ipmemorystore/SameL3NetworkResponse.java index d040dcc3d608..291aca8fc611 100644 --- a/core/java/android/net/ipmemorystore/SameL3NetworkResponse.java +++ b/core/java/android/net/ipmemorystore/SameL3NetworkResponse.java @@ -91,7 +91,8 @@ public class SameL3NetworkResponse { return confidence > 0.5 ? NETWORK_SAME : NETWORK_DIFFERENT; } - SameL3NetworkResponse(@NonNull final String l2Key1, @NonNull final String l2Key2, + /** @hide */ + public SameL3NetworkResponse(@NonNull final String l2Key1, @NonNull final String l2Key2, final float confidence) { this.l2Key1 = l2Key1; this.l2Key2 = l2Key2; |