diff options
| -rw-r--r-- | services/core/java/com/android/server/net/NetworkStatsService.java | 38 |
1 files changed, 28 insertions, 10 deletions
diff --git a/services/core/java/com/android/server/net/NetworkStatsService.java b/services/core/java/com/android/server/net/NetworkStatsService.java index dcbdfdf7a297..cf5a41232123 100644 --- a/services/core/java/com/android/server/net/NetworkStatsService.java +++ b/services/core/java/com/android/server/net/NetworkStatsService.java @@ -1311,21 +1311,39 @@ public class NetworkStatsService extends INetworkStatsService.Stub { } // Traffic occurring on stacked interfaces is usually clatd. - // UID stats are always counted on the stacked interface and never - // on the base interface, because the packets on the base interface - // do not actually match application sockets until they are translated. // - // Interface stats are more complicated. Packets subject to BPF offload - // never appear on the base interface and only appear on the stacked - // interface, so to ensure those packets increment interface stats, interface - // stats from stacked interfaces must be collected. + // UID stats are always counted on the stacked interface and never on the base + // interface, because the packets on the base interface do not actually match + // application sockets (they're not IPv4) and thus the app uid is not known. + // For receive this is obvious: packets must be translated from IPv6 to IPv4 + // before the application socket can be found. + // For transmit: either they go through the clat daemon which by virtue of going + // through userspace strips the original socket association during the IPv4 to + // IPv6 translation process, or they are offloaded by eBPF, which doesn't: + // However, on an ebpf device the accounting is done in cgroup ebpf hooks, + // which don't trigger again post ebpf translation. + // (as such stats accounted to the clat uid are ignored) + // + // Interface stats are more complicated. + // + // eBPF offloaded 464xlat'ed packets never hit base interface ip6tables, and thus + // *all* statistics are collected by iptables on the stacked v4-* interface. + // + // Additionally for ingress all packets bound for the clat IPv6 address are dropped + // in ip6tables raw prerouting and thus even non-offloaded packets are only + // accounted for on the stacked interface. + // + // For egress, packets subject to eBPF offload never appear on the base interface + // and only appear on the stacked interface. Thus to ensure packets increment + // interface stats, we must collate data from stacked interfaces. For xt_qtaguid + // (or non eBPF offloaded) TX they would appear on both, however egress interface + // accounting is explicitly bypassed for traffic from the clat uid. + // final List<LinkProperties> stackedLinks = state.linkProperties.getStackedLinks(); for (LinkProperties stackedLink : stackedLinks) { final String stackedIface = stackedLink.getInterfaceName(); if (stackedIface != null) { - if (mUseBpfTrafficStats) { - findOrCreateNetworkIdentitySet(mActiveIfaces, stackedIface).add(ident); - } + findOrCreateNetworkIdentitySet(mActiveIfaces, stackedIface).add(ident); findOrCreateNetworkIdentitySet(mActiveUidIfaces, stackedIface).add(ident); if (isMobile) { mobileIfaces.add(stackedIface); |