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![Toke Høiland-Jørgensen](/assets/img/avatar_default.png)
Fix all files in samples/bpf to include libbpf header files with the bpf/
prefix, to be consistent with external users of the library. Also ensure
that all includes of exported libbpf header files (those that are exported
on 'make install' of the library) use bracketed includes instead of quoted.
To make sure no new files are introduced that doesn't include the bpf/
prefix in its include, remove tools/lib/bpf from the include path entirely,
and use tools/lib instead.
Fixes: 6910d7d386
("selftests/bpf: Ensure bpf_helper_defs.h are taken from selftests dir")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/157952560911.1683545.8795966751309534150.stgit@toke.dk
237 lines
5.6 KiB
C
237 lines
5.6 KiB
C
/* Copyright (c) 2016 Facebook
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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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* This program shows how to use bpf_xdp_adjust_head() by
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* encapsulating the incoming packet in an IPv4/v6 header
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* and then XDP_TX it out.
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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/bpf_helpers.h>
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#include "xdp_tx_iptunnel_common.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, __u64);
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__uint(max_entries, 256);
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} rxcnt SEC(".maps");
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struct {
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__uint(type, BPF_MAP_TYPE_HASH);
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__type(key, struct vip);
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__type(value, struct iptnl_info);
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__uint(max_entries, MAX_IPTNL_ENTRIES);
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} vip2tnl SEC(".maps");
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static __always_inline void count_tx(u32 protocol)
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{
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u64 *rxcnt_count;
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rxcnt_count = bpf_map_lookup_elem(&rxcnt, &protocol);
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if (rxcnt_count)
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*rxcnt_count += 1;
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}
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static __always_inline int get_dport(void *trans_data, void *data_end,
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u8 protocol)
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{
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struct tcphdr *th;
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struct udphdr *uh;
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switch (protocol) {
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case IPPROTO_TCP:
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th = (struct tcphdr *)trans_data;
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if (th + 1 > data_end)
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return -1;
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return th->dest;
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case IPPROTO_UDP:
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uh = (struct udphdr *)trans_data;
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if (uh + 1 > data_end)
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return -1;
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return uh->dest;
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default:
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return 0;
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}
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}
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static __always_inline void set_ethhdr(struct ethhdr *new_eth,
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const struct ethhdr *old_eth,
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const struct iptnl_info *tnl,
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__be16 h_proto)
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{
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memcpy(new_eth->h_source, old_eth->h_dest, sizeof(new_eth->h_source));
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memcpy(new_eth->h_dest, tnl->dmac, sizeof(new_eth->h_dest));
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new_eth->h_proto = h_proto;
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}
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static __always_inline int handle_ipv4(struct xdp_md *xdp)
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{
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void *data_end = (void *)(long)xdp->data_end;
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void *data = (void *)(long)xdp->data;
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struct iptnl_info *tnl;
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struct ethhdr *new_eth;
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struct ethhdr *old_eth;
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struct iphdr *iph = data + sizeof(struct ethhdr);
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u16 *next_iph_u16;
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u16 payload_len;
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struct vip vip = {};
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int dport;
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u32 csum = 0;
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int i;
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if (iph + 1 > data_end)
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return XDP_DROP;
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dport = get_dport(iph + 1, data_end, iph->protocol);
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if (dport == -1)
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return XDP_DROP;
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vip.protocol = iph->protocol;
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vip.family = AF_INET;
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vip.daddr.v4 = iph->daddr;
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vip.dport = dport;
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payload_len = ntohs(iph->tot_len);
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tnl = bpf_map_lookup_elem(&vip2tnl, &vip);
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/* It only does v4-in-v4 */
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if (!tnl || tnl->family != AF_INET)
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return XDP_PASS;
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/* The vip key is found. Add an IP header and send it out */
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if (bpf_xdp_adjust_head(xdp, 0 - (int)sizeof(struct iphdr)))
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return XDP_DROP;
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data = (void *)(long)xdp->data;
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data_end = (void *)(long)xdp->data_end;
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new_eth = data;
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iph = data + sizeof(*new_eth);
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old_eth = data + sizeof(*iph);
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if (new_eth + 1 > data_end ||
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old_eth + 1 > data_end ||
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iph + 1 > data_end)
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return XDP_DROP;
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set_ethhdr(new_eth, old_eth, tnl, htons(ETH_P_IP));
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iph->version = 4;
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iph->ihl = sizeof(*iph) >> 2;
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iph->frag_off = 0;
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iph->protocol = IPPROTO_IPIP;
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iph->check = 0;
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iph->tos = 0;
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iph->tot_len = htons(payload_len + sizeof(*iph));
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iph->daddr = tnl->daddr.v4;
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iph->saddr = tnl->saddr.v4;
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iph->ttl = 8;
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next_iph_u16 = (u16 *)iph;
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#pragma clang loop unroll(full)
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for (i = 0; i < sizeof(*iph) >> 1; i++)
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csum += *next_iph_u16++;
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iph->check = ~((csum & 0xffff) + (csum >> 16));
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count_tx(vip.protocol);
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return XDP_TX;
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}
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static __always_inline int handle_ipv6(struct xdp_md *xdp)
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{
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void *data_end = (void *)(long)xdp->data_end;
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void *data = (void *)(long)xdp->data;
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struct iptnl_info *tnl;
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struct ethhdr *new_eth;
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struct ethhdr *old_eth;
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struct ipv6hdr *ip6h = data + sizeof(struct ethhdr);
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__u16 payload_len;
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struct vip vip = {};
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int dport;
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if (ip6h + 1 > data_end)
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return XDP_DROP;
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dport = get_dport(ip6h + 1, data_end, ip6h->nexthdr);
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if (dport == -1)
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return XDP_DROP;
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vip.protocol = ip6h->nexthdr;
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vip.family = AF_INET6;
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memcpy(vip.daddr.v6, ip6h->daddr.s6_addr32, sizeof(vip.daddr));
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vip.dport = dport;
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payload_len = ip6h->payload_len;
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tnl = bpf_map_lookup_elem(&vip2tnl, &vip);
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/* It only does v6-in-v6 */
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if (!tnl || tnl->family != AF_INET6)
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return XDP_PASS;
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/* The vip key is found. Add an IP header and send it out */
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if (bpf_xdp_adjust_head(xdp, 0 - (int)sizeof(struct ipv6hdr)))
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return XDP_DROP;
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data = (void *)(long)xdp->data;
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data_end = (void *)(long)xdp->data_end;
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new_eth = data;
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ip6h = data + sizeof(*new_eth);
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old_eth = data + sizeof(*ip6h);
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if (new_eth + 1 > data_end ||
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old_eth + 1 > data_end ||
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ip6h + 1 > data_end)
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return XDP_DROP;
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set_ethhdr(new_eth, old_eth, tnl, htons(ETH_P_IPV6));
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ip6h->version = 6;
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ip6h->priority = 0;
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memset(ip6h->flow_lbl, 0, sizeof(ip6h->flow_lbl));
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ip6h->payload_len = htons(ntohs(payload_len) + sizeof(*ip6h));
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ip6h->nexthdr = IPPROTO_IPV6;
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ip6h->hop_limit = 8;
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memcpy(ip6h->saddr.s6_addr32, tnl->saddr.v6, sizeof(tnl->saddr.v6));
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memcpy(ip6h->daddr.s6_addr32, tnl->daddr.v6, sizeof(tnl->daddr.v6));
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count_tx(vip.protocol);
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return XDP_TX;
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}
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SEC("xdp_tx_iptunnel")
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int _xdp_tx_iptunnel(struct xdp_md *xdp)
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{
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void *data_end = (void *)(long)xdp->data_end;
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void *data = (void *)(long)xdp->data;
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struct ethhdr *eth = data;
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__u16 h_proto;
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if (eth + 1 > data_end)
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return XDP_DROP;
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h_proto = eth->h_proto;
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if (h_proto == htons(ETH_P_IP))
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return handle_ipv4(xdp);
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else if (h_proto == htons(ETH_P_IPV6))
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return handle_ipv6(xdp);
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else
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return XDP_PASS;
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}
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char _license[] SEC("license") = "GPL";
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