1// SPDX-License-Identifier: GPL-2.0
2
3#include <vmlinux.h>
4#include "xdp_metadata.h"
5#include <bpf/bpf_helpers.h>
6#include <bpf/bpf_endian.h>
7
8struct {
9	__uint(type, BPF_MAP_TYPE_XSKMAP);
10	__uint(max_entries, 256);
11	__type(key, __u32);
12	__type(value, __u32);
13} xsk SEC(".maps");
14
15__u64 pkts_skip = 0;
16__u64 pkts_fail = 0;
17__u64 pkts_redir = 0;
18
19extern int bpf_xdp_metadata_rx_timestamp(const struct xdp_md *ctx,
20					 __u64 *timestamp) __ksym;
21extern int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx, __u32 *hash,
22				    enum xdp_rss_hash_type *rss_type) __ksym;
23extern int bpf_xdp_metadata_rx_vlan_tag(const struct xdp_md *ctx,
24					__be16 *vlan_proto,
25					__u16 *vlan_tci) __ksym;
26
27SEC("xdp.frags")
28int rx(struct xdp_md *ctx)
29{
30	void *data, *data_meta, *data_end;
31	struct ipv6hdr *ip6h = NULL;
32	struct udphdr *udp = NULL;
33	struct iphdr *iph = NULL;
34	struct xdp_meta *meta;
35	struct ethhdr *eth;
36	int err;
37
38	data = (void *)(long)ctx->data;
39	data_end = (void *)(long)ctx->data_end;
40	eth = data;
41
42	if (eth + 1 < data_end && (eth->h_proto == bpf_htons(ETH_P_8021AD) ||
43				   eth->h_proto == bpf_htons(ETH_P_8021Q)))
44		eth = (void *)eth + sizeof(struct vlan_hdr);
45
46	if (eth + 1 < data_end && eth->h_proto == bpf_htons(ETH_P_8021Q))
47		eth = (void *)eth + sizeof(struct vlan_hdr);
48
49	if (eth + 1 < data_end) {
50		if (eth->h_proto == bpf_htons(ETH_P_IP)) {
51			iph = (void *)(eth + 1);
52			if (iph + 1 < data_end && iph->protocol == IPPROTO_UDP)
53				udp = (void *)(iph + 1);
54		}
55		if (eth->h_proto == bpf_htons(ETH_P_IPV6)) {
56			ip6h = (void *)(eth + 1);
57			if (ip6h + 1 < data_end && ip6h->nexthdr == IPPROTO_UDP)
58				udp = (void *)(ip6h + 1);
59		}
60		if (udp && udp + 1 > data_end)
61			udp = NULL;
62	}
63
64	if (!udp) {
65		__sync_add_and_fetch(&pkts_skip, 1);
66		return XDP_PASS;
67	}
68
69	/* Forwarding UDP:9091 to AF_XDP */
70	if (udp->dest != bpf_htons(9091)) {
71		__sync_add_and_fetch(&pkts_skip, 1);
72		return XDP_PASS;
73	}
74
75	err = bpf_xdp_adjust_meta(ctx, -(int)sizeof(struct xdp_meta));
76	if (err) {
77		__sync_add_and_fetch(&pkts_fail, 1);
78		return XDP_PASS;
79	}
80
81	data = (void *)(long)ctx->data;
82	data_meta = (void *)(long)ctx->data_meta;
83	meta = data_meta;
84
85	if (meta + 1 > data) {
86		__sync_add_and_fetch(&pkts_fail, 1);
87		return XDP_PASS;
88	}
89
90	meta->hint_valid = 0;
91
92	meta->xdp_timestamp = bpf_ktime_get_tai_ns();
93	err = bpf_xdp_metadata_rx_timestamp(ctx, &meta->rx_timestamp);
94	if (err)
95		meta->rx_timestamp_err = err;
96	else
97		meta->hint_valid |= XDP_META_FIELD_TS;
98
99	err = bpf_xdp_metadata_rx_hash(ctx, &meta->rx_hash,
100				       &meta->rx_hash_type);
101	if (err)
102		meta->rx_hash_err = err;
103	else
104		meta->hint_valid |= XDP_META_FIELD_RSS;
105
106	err = bpf_xdp_metadata_rx_vlan_tag(ctx, &meta->rx_vlan_proto,
107					   &meta->rx_vlan_tci);
108	if (err)
109		meta->rx_vlan_tag_err = err;
110	else
111		meta->hint_valid |= XDP_META_FIELD_VLAN_TAG;
112
113	__sync_add_and_fetch(&pkts_redir, 1);
114	return bpf_redirect_map(&xsk, ctx->rx_queue_index, XDP_PASS);
115}
116
117char _license[] SEC("license") = "GPL";
118