tools/testing/selftests/bpf/progs/mptcp_sock.c

   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")
  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")
  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 }