1
2
3
4#include <linux/bpf.h>
5#include <netinet/in.h>
6#include <stdbool.h>
7
8#include <bpf/bpf_helpers.h>
9#include <bpf/bpf_endian.h>
10#include "bpf_tcp_helpers.h"
11
12enum bpf_linum_array_idx {
13 EGRESS_LINUM_IDX,
14 INGRESS_LINUM_IDX,
15 __NR_BPF_LINUM_ARRAY_IDX,
16};
17
18struct {
19 __uint(type, BPF_MAP_TYPE_ARRAY);
20 __uint(max_entries, __NR_BPF_LINUM_ARRAY_IDX);
21 __type(key, __u32);
22 __type(value, __u32);
23} linum_map SEC(".maps");
24
25struct bpf_spinlock_cnt {
26 struct bpf_spin_lock lock;
27 __u32 cnt;
28};
29
30struct {
31 __uint(type, BPF_MAP_TYPE_SK_STORAGE);
32 __uint(map_flags, BPF_F_NO_PREALLOC);
33 __type(key, int);
34 __type(value, struct bpf_spinlock_cnt);
35} sk_pkt_out_cnt SEC(".maps");
36
37struct {
38 __uint(type, BPF_MAP_TYPE_SK_STORAGE);
39 __uint(map_flags, BPF_F_NO_PREALLOC);
40 __type(key, int);
41 __type(value, struct bpf_spinlock_cnt);
42} sk_pkt_out_cnt10 SEC(".maps");
43
44struct bpf_tcp_sock listen_tp = {};
45struct sockaddr_in6 srv_sa6 = {};
46struct bpf_tcp_sock cli_tp = {};
47struct bpf_tcp_sock srv_tp = {};
48struct bpf_sock listen_sk = {};
49struct bpf_sock srv_sk = {};
50struct bpf_sock cli_sk = {};
51__u64 parent_cg_id = 0;
52__u64 child_cg_id = 0;
53__u64 lsndtime = 0;
54
55static bool is_loopback6(__u32 *a6)
56{
57 return !a6[0] && !a6[1] && !a6[2] && a6[3] == bpf_htonl(1);
58}
59
60static void skcpy(struct bpf_sock *dst,
61 const struct bpf_sock *src)
62{
63 dst->bound_dev_if = src->bound_dev_if;
64 dst->family = src->family;
65 dst->type = src->type;
66 dst->protocol = src->protocol;
67 dst->mark = src->mark;
68 dst->priority = src->priority;
69 dst->src_ip4 = src->src_ip4;
70 dst->src_ip6[0] = src->src_ip6[0];
71 dst->src_ip6[1] = src->src_ip6[1];
72 dst->src_ip6[2] = src->src_ip6[2];
73 dst->src_ip6[3] = src->src_ip6[3];
74 dst->src_port = src->src_port;
75 dst->dst_ip4 = src->dst_ip4;
76 dst->dst_ip6[0] = src->dst_ip6[0];
77 dst->dst_ip6[1] = src->dst_ip6[1];
78 dst->dst_ip6[2] = src->dst_ip6[2];
79 dst->dst_ip6[3] = src->dst_ip6[3];
80 dst->dst_port = src->dst_port;
81 dst->state = src->state;
82}
83
84static void tpcpy(struct bpf_tcp_sock *dst,
85 const struct bpf_tcp_sock *src)
86{
87 dst->snd_cwnd = src->snd_cwnd;
88 dst->srtt_us = src->srtt_us;
89 dst->rtt_min = src->rtt_min;
90 dst->snd_ssthresh = src->snd_ssthresh;
91 dst->rcv_nxt = src->rcv_nxt;
92 dst->snd_nxt = src->snd_nxt;
93 dst->snd_una = src->snd_una;
94 dst->mss_cache = src->mss_cache;
95 dst->ecn_flags = src->ecn_flags;
96 dst->rate_delivered = src->rate_delivered;
97 dst->rate_interval_us = src->rate_interval_us;
98 dst->packets_out = src->packets_out;
99 dst->retrans_out = src->retrans_out;
100 dst->total_retrans = src->total_retrans;
101 dst->segs_in = src->segs_in;
102 dst->data_segs_in = src->data_segs_in;
103 dst->segs_out = src->segs_out;
104 dst->data_segs_out = src->data_segs_out;
105 dst->lost_out = src->lost_out;
106 dst->sacked_out = src->sacked_out;
107 dst->bytes_received = src->bytes_received;
108 dst->bytes_acked = src->bytes_acked;
109}
110
111
112#define CG_OK 1
113
114#define RET_LOG() ({ \
115 linum = __LINE__; \
116 bpf_map_update_elem(&linum_map, &linum_idx, &linum, BPF_NOEXIST); \
117 return CG_OK; \
118})
119
120SEC("cgroup_skb/egress")
121int egress_read_sock_fields(struct __sk_buff *skb)
122{
123 struct bpf_spinlock_cnt cli_cnt_init = { .lock = 0, .cnt = 0xeB9F };
124 struct bpf_spinlock_cnt *pkt_out_cnt, *pkt_out_cnt10;
125 struct bpf_tcp_sock *tp, *tp_ret;
126 struct bpf_sock *sk, *sk_ret;
127 __u32 linum, linum_idx;
128 struct tcp_sock *ktp;
129
130 linum_idx = EGRESS_LINUM_IDX;
131
132 sk = skb->sk;
133 if (!sk)
134 RET_LOG();
135
136
137
138
139 if (sk->family != AF_INET6 || !is_loopback6(sk->src_ip6) ||
140 sk->state == 10)
141 return CG_OK;
142
143 if (sk->src_port == bpf_ntohs(srv_sa6.sin6_port)) {
144
145 sk_ret = &srv_sk;
146 tp_ret = &srv_tp;
147 } else if (sk->dst_port == srv_sa6.sin6_port) {
148
149 sk_ret = &cli_sk;
150 tp_ret = &cli_tp;
151 } else {
152
153 return CG_OK;
154 }
155
156
157 sk = bpf_sk_fullsock(sk);
158 if (!sk)
159 RET_LOG();
160
161
162 if (sk->protocol != IPPROTO_TCP)
163 return CG_OK;
164
165 tp = bpf_tcp_sock(sk);
166 if (!tp)
167 RET_LOG();
168
169 skcpy(sk_ret, sk);
170 tpcpy(tp_ret, tp);
171
172 if (sk_ret == &srv_sk) {
173 ktp = bpf_skc_to_tcp_sock(sk);
174
175 if (!ktp)
176 RET_LOG();
177
178 lsndtime = ktp->lsndtime;
179
180 child_cg_id = bpf_sk_cgroup_id(ktp);
181 if (!child_cg_id)
182 RET_LOG();
183
184 parent_cg_id = bpf_sk_ancestor_cgroup_id(ktp, 2);
185 if (!parent_cg_id)
186 RET_LOG();
187
188
189 pkt_out_cnt = bpf_sk_storage_get(&sk_pkt_out_cnt, ktp, 0, 0);
190 pkt_out_cnt10 = bpf_sk_storage_get(&sk_pkt_out_cnt10, ktp,
191 0, 0);
192 } else {
193 pkt_out_cnt = bpf_sk_storage_get(&sk_pkt_out_cnt, sk,
194 &cli_cnt_init,
195 BPF_SK_STORAGE_GET_F_CREATE);
196 pkt_out_cnt10 = bpf_sk_storage_get(&sk_pkt_out_cnt10,
197 sk, &cli_cnt_init,
198 BPF_SK_STORAGE_GET_F_CREATE);
199 }
200
201 if (!pkt_out_cnt || !pkt_out_cnt10)
202 RET_LOG();
203
204
205
206
207
208 pkt_out_cnt->cnt += 1;
209 bpf_spin_lock(&pkt_out_cnt10->lock);
210 pkt_out_cnt10->cnt += 10;
211 bpf_spin_unlock(&pkt_out_cnt10->lock);
212
213 return CG_OK;
214}
215
216SEC("cgroup_skb/ingress")
217int ingress_read_sock_fields(struct __sk_buff *skb)
218{
219 struct bpf_tcp_sock *tp;
220 __u32 linum, linum_idx;
221 struct bpf_sock *sk;
222
223 linum_idx = INGRESS_LINUM_IDX;
224
225 sk = skb->sk;
226 if (!sk)
227 RET_LOG();
228
229
230 if (sk->family != AF_INET6 || !is_loopback6(sk->src_ip6) ||
231 sk->src_port != bpf_ntohs(srv_sa6.sin6_port))
232 return CG_OK;
233
234
235 if (sk->state != 10)
236 return CG_OK;
237
238
239 sk = bpf_sk_fullsock(sk);
240 if (!sk)
241 RET_LOG();
242
243 tp = bpf_tcp_sock(sk);
244 if (!tp)
245 RET_LOG();
246
247 skcpy(&listen_sk, sk);
248 tpcpy(&listen_tp, tp);
249
250 return CG_OK;
251}
252
253char _license[] SEC("license") = "GPL";
254
