1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2020, Tessares SA. */
3 /* Copyright (c) 2022, SUSE. */
4
5 #include <linux/bpf.h>
6 #include <bpf/bpf_helpers.h>
7 #include "bpf_tcp_helpers.h"
8
9 char _license[] SEC("license") = "GPL";
10 __u32 token = 0;
11
12 struct mptcp_storage {
13 __u32 invoked;
14 __u32 is_mptcp;
15 struct sock *sk;
16 __u32 token;
17 struct sock *first;
18 char ca_name[TCP_CA_NAME_MAX];
19 };
20
21 struct {
22 __uint(type, BPF_MAP_TYPE_SK_STORAGE);
23 __uint(map_flags, BPF_F_NO_PREALLOC);
24 __type(key, int);
25 __type(value, struct mptcp_storage);
26 } socket_storage_map SEC(".maps");
27
28 SEC("sockops")
_sockops(struct bpf_sock_ops * ctx)29 int _sockops(struct bpf_sock_ops *ctx)
30 {
31 struct mptcp_storage *storage;
32 struct mptcp_sock *msk;
33 int op = (int)ctx->op;
34 struct tcp_sock *tsk;
35 struct bpf_sock *sk;
36 bool is_mptcp;
37
38 if (op != BPF_SOCK_OPS_TCP_CONNECT_CB)
39 return 1;
40
41 sk = ctx->sk;
42 if (!sk)
43 return 1;
44
45 tsk = bpf_skc_to_tcp_sock(sk);
46 if (!tsk)
47 return 1;
48
49 is_mptcp = bpf_core_field_exists(tsk->is_mptcp) ? tsk->is_mptcp : 0;
50 if (!is_mptcp) {
51 storage = bpf_sk_storage_get(&socket_storage_map, sk, 0,
52 BPF_SK_STORAGE_GET_F_CREATE);
53 if (!storage)
54 return 1;
55
56 storage->token = 0;
57 __builtin_memset(storage->ca_name, 0, TCP_CA_NAME_MAX);
58 storage->first = NULL;
59 } else {
60 msk = bpf_skc_to_mptcp_sock(sk);
61 if (!msk)
62 return 1;
63
64 storage = bpf_sk_storage_get(&socket_storage_map, msk, 0,
65 BPF_SK_STORAGE_GET_F_CREATE);
66 if (!storage)
67 return 1;
68
69 storage->token = msk->token;
70 __builtin_memcpy(storage->ca_name, msk->ca_name, TCP_CA_NAME_MAX);
71 storage->first = msk->first;
72 }
73 storage->invoked++;
74 storage->is_mptcp = is_mptcp;
75 storage->sk = (struct sock *)sk;
76
77 return 1;
78 }
79
80 SEC("fentry/mptcp_pm_new_connection")
BPF_PROG(trace_mptcp_pm_new_connection,struct mptcp_sock * msk,const struct sock * ssk,int server_side)81 int BPF_PROG(trace_mptcp_pm_new_connection, struct mptcp_sock *msk,
82 const struct sock *ssk, int server_side)
83 {
84 if (!server_side)
85 token = msk->token;
86
87 return 0;
88 }
89