Introduce bpf_xdp_flow_lookup kfunc in order to perform the lookup of a given flowtable entry based on the fib tuple of incoming traffic. bpf_xdp_flow_lookup can be used as building block to offload in XDP the sw flowtable processing when the hw support is not available. This series has been tested running the xdp_flowtable_offload eBPF program on an ixgbe 10Gbps NIC (eno2) in order to XDP_REDIRECT the TCP traffic to a veth pair (veth0-veth1) based on the content of the nf_flowtable as soon as the TCP connection is in the established state: [tcp client] (eno1) == LAN == (eno2) xdp_flowtable_offload [XDP_REDIRECT] --> veth0 == veth1 [tcp server] table inet filter { flowtable ft { hook ingress priority filter devices = { eno2, veth0 } } chain forward { type filter hook forward priority filter meta l4proto { tcp, udp } flow add @ft } } - sw flowtable [1 TCP stream, T = 300s]: ~ 6.2 Gbps - xdp flowtable [1 TCP stream, T = 300s]: ~ 7.6 Gbps - sw flowtable [3 TCP stream, T = 300s]: ~ 7.7 Gbps - xdp flowtable [3 TCP stream, T = 300s]: ~ 8.8 Gbps Changes since v5: - remove unused nf_flow_offload_xdp_cancel routine - add missing __bpf_kfunc_start_defs()/__bpf_kfunc_end_defs() - remove unused definition Changes since v4: - add missing BPF_NO_KFUNC_PROTOTYPES macro to selftest Changes since v3: - move flowtable map utilities in nf_flow_table_xdp.c Changes since v2: - introduce bpf_flowtable_opts struct in bpf_xdp_flow_lookup signature - get rid of xdp_flowtable_offload bpf sample - get rid of test_xdp_flowtable.sh for selftest and rely on prog_tests instead - rename bpf_xdp_flow_offload_lookup in bpf_xdp_flow_lookup Changes since v1: - return NULL in bpf_xdp_flow_offload_lookup kfunc in case of error - take into account kfunc registration possible failures Changes since RFC: - fix compilation error if BTF is not enabled Florian Westphal (1): netfilter: nf_tables: add flowtable map for xdp offload Lorenzo Bianconi (2): netfilter: add bpf_xdp_flow_lookup kfunc selftests/bpf: Add selftest for bpf_xdp_flow_lookup kfunc include/net/netfilter/nf_flow_table.h | 15 ++ net/netfilter/Makefile | 7 +- net/netfilter/nf_flow_table_bpf.c | 121 +++++++++++++ net/netfilter/nf_flow_table_inet.c | 2 +- net/netfilter/nf_flow_table_offload.c | 2 +- net/netfilter/nf_flow_table_xdp.c | 147 +++++++++++++++ tools/testing/selftests/bpf/config | 13 ++ .../selftests/bpf/prog_tests/xdp_flowtable.c | 168 ++++++++++++++++++ .../selftests/bpf/progs/xdp_flowtable.c | 144 +++++++++++++++ 9 files changed, 616 insertions(+), 3 deletions(-) create mode 100644 net/netfilter/nf_flow_table_bpf.c create mode 100644 net/netfilter/nf_flow_table_xdp.c create mode 100644 tools/testing/selftests/bpf/prog_tests/xdp_flowtable.c create mode 100644 tools/testing/selftests/bpf/progs/xdp_flowtable.c -- 2.45.2