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1// SPDX-License-Identifier: GPL-2.02/* Copyright (c) 2022 Intel */3 4#include <linux/bpf.h>5#include <bpf/bpf_helpers.h>6#include <linux/if_ether.h>7#include "xsk_xdp_common.h"8 9struct {10 __uint(type, BPF_MAP_TYPE_XSKMAP);11 __uint(max_entries, 2);12 __uint(key_size, sizeof(int));13 __uint(value_size, sizeof(int));14} xsk SEC(".maps");15 16static unsigned int idx;17int count = 0;18 19SEC("xdp.frags") int xsk_def_prog(struct xdp_md *xdp)20{21 return bpf_redirect_map(&xsk, 0, XDP_DROP);22}23 24SEC("xdp.frags") int xsk_xdp_drop(struct xdp_md *xdp)25{26 /* Drop every other packet */27 if (idx++ % 2)28 return XDP_DROP;29 30 return bpf_redirect_map(&xsk, 0, XDP_DROP);31}32 33SEC("xdp.frags") int xsk_xdp_populate_metadata(struct xdp_md *xdp)34{35 void *data, *data_meta;36 struct xdp_info *meta;37 int err;38 39 /* Reserve enough for all custom metadata. */40 err = bpf_xdp_adjust_meta(xdp, -(int)sizeof(struct xdp_info));41 if (err)42 return XDP_DROP;43 44 data = (void *)(long)xdp->data;45 data_meta = (void *)(long)xdp->data_meta;46 47 if (data_meta + sizeof(struct xdp_info) > data)48 return XDP_DROP;49 50 meta = data_meta;51 meta->count = count++;52 53 return bpf_redirect_map(&xsk, 0, XDP_DROP);54}55 56SEC("xdp") int xsk_xdp_shared_umem(struct xdp_md *xdp)57{58 void *data = (void *)(long)xdp->data;59 void *data_end = (void *)(long)xdp->data_end;60 struct ethhdr *eth = data;61 62 if (eth + 1 > data_end)63 return XDP_DROP;64 65 /* Redirecting packets based on the destination MAC address */66 idx = ((unsigned int)(eth->h_dest[5])) / 2;67 if (idx > MAX_SOCKETS)68 return XDP_DROP;69 70 return bpf_redirect_map(&xsk, idx, XDP_DROP);71}72 73char _license[] SEC("license") = "GPL";74