forked from Minki/linux
451d1dc886
Since, the new syntax of BTF-defined map has been introduced,
the syntax for using maps under samples directory are mixed up.
For example, some are already using the new syntax, and some are using
existing syntax by calling them as 'legacy'.
As stated at commit abd29c9314 ("libbpf: allow specifying map
definitions using BTF"), the BTF-defined map has more compatablility
with extending supported map definition features.
The commit doesn't replace all of the map to new BTF-defined map,
because some of the samples still use bpf_load instead of libbpf, which
can't properly create BTF-defined map.
This will only updates the samples which uses libbpf API for loading bpf
program. (ex. bpf_prog_load_xattr)
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
115 lines
2.4 KiB
C
115 lines
2.4 KiB
C
/* Copyright (c) 2016 PLUMgrid
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of version 2 of the GNU General Public
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* License as published by the Free Software Foundation.
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*/
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#define KBUILD_MODNAME "foo"
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#include <uapi/linux/bpf.h>
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#include <linux/in.h>
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#include <linux/if_ether.h>
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#include <linux/if_packet.h>
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#include <linux/if_vlan.h>
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#include <linux/ip.h>
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#include <linux/ipv6.h>
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#include "bpf_helpers.h"
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struct {
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__uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
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__type(key, u32);
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__type(value, long);
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__uint(max_entries, 256);
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} rxcnt SEC(".maps");
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static void swap_src_dst_mac(void *data)
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{
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unsigned short *p = data;
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unsigned short dst[3];
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dst[0] = p[0];
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dst[1] = p[1];
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dst[2] = p[2];
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p[0] = p[3];
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p[1] = p[4];
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p[2] = p[5];
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p[3] = dst[0];
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p[4] = dst[1];
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p[5] = dst[2];
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}
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static int parse_ipv4(void *data, u64 nh_off, void *data_end)
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{
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struct iphdr *iph = data + nh_off;
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if (iph + 1 > data_end)
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return 0;
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return iph->protocol;
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}
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static int parse_ipv6(void *data, u64 nh_off, void *data_end)
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{
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struct ipv6hdr *ip6h = data + nh_off;
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if (ip6h + 1 > data_end)
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return 0;
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return ip6h->nexthdr;
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}
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SEC("xdp1")
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int xdp_prog1(struct xdp_md *ctx)
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{
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void *data_end = (void *)(long)ctx->data_end;
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void *data = (void *)(long)ctx->data;
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struct ethhdr *eth = data;
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int rc = XDP_DROP;
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long *value;
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u16 h_proto;
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u64 nh_off;
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u32 ipproto;
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nh_off = sizeof(*eth);
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if (data + nh_off > data_end)
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return rc;
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h_proto = eth->h_proto;
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if (h_proto == htons(ETH_P_8021Q) || h_proto == htons(ETH_P_8021AD)) {
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struct vlan_hdr *vhdr;
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vhdr = data + nh_off;
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nh_off += sizeof(struct vlan_hdr);
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if (data + nh_off > data_end)
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return rc;
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h_proto = vhdr->h_vlan_encapsulated_proto;
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}
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if (h_proto == htons(ETH_P_8021Q) || h_proto == htons(ETH_P_8021AD)) {
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struct vlan_hdr *vhdr;
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vhdr = data + nh_off;
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nh_off += sizeof(struct vlan_hdr);
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if (data + nh_off > data_end)
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return rc;
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h_proto = vhdr->h_vlan_encapsulated_proto;
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}
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if (h_proto == htons(ETH_P_IP))
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ipproto = parse_ipv4(data, nh_off, data_end);
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else if (h_proto == htons(ETH_P_IPV6))
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ipproto = parse_ipv6(data, nh_off, data_end);
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else
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ipproto = 0;
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value = bpf_map_lookup_elem(&rxcnt, &ipproto);
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if (value)
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*value += 1;
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if (ipproto == IPPROTO_UDP) {
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swap_src_dst_mac(data);
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rc = XDP_TX;
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}
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return rc;
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}
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char _license[] SEC("license") = "GPL";
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