| 1 | // SPDX-License-Identifier: GPL-2.0 |
|---|---|
| 2 | #include <linux/bpf.h> |
| 3 | #include <bpf/bpf_helpers.h> |
| 4 | |
| 5 | char _license[] SEC("license") = "GPL"; |
| 6 | |
| 7 | struct tcp_rtt_storage { |
| 8 | __u32 invoked; |
| 9 | __u32 dsack_dups; |
| 10 | __u32 delivered; |
| 11 | __u32 delivered_ce; |
| 12 | __u32 icsk_retransmits; |
| 13 | }; |
| 14 | |
| 15 | struct { |
| 16 | __uint(type, BPF_MAP_TYPE_SK_STORAGE); |
| 17 | __uint(map_flags, BPF_F_NO_PREALLOC); |
| 18 | __type(key, int); |
| 19 | __type(value, struct tcp_rtt_storage); |
| 20 | } socket_storage_map SEC(".maps"); |
| 21 | |
| 22 | SEC("sockops") |
| 23 | int _sockops(struct bpf_sock_ops *ctx) |
| 24 | { |
| 25 | struct tcp_rtt_storage *storage; |
| 26 | struct bpf_tcp_sock *tcp_sk; |
| 27 | int op = (int) ctx->op; |
| 28 | struct bpf_sock *sk; |
| 29 | |
| 30 | sk = ctx->sk; |
| 31 | if (!sk) |
| 32 | return 1; |
| 33 | |
| 34 | storage = bpf_sk_storage_get(&socket_storage_map, sk, 0, |
| 35 | BPF_SK_STORAGE_GET_F_CREATE); |
| 36 | if (!storage) |
| 37 | return 1; |
| 38 | |
| 39 | if (op == BPF_SOCK_OPS_TCP_CONNECT_CB) { |
| 40 | bpf_sock_ops_cb_flags_set(ctx, BPF_SOCK_OPS_RTT_CB_FLAG); |
| 41 | return 1; |
| 42 | } |
| 43 | |
| 44 | if (op != BPF_SOCK_OPS_RTT_CB) |
| 45 | return 1; |
| 46 | |
| 47 | tcp_sk = bpf_tcp_sock(sk); |
| 48 | if (!tcp_sk) |
| 49 | return 1; |
| 50 | |
| 51 | storage->invoked++; |
| 52 | |
| 53 | storage->dsack_dups = tcp_sk->dsack_dups; |
| 54 | storage->delivered = tcp_sk->delivered; |
| 55 | storage->delivered_ce = tcp_sk->delivered_ce; |
| 56 | storage->icsk_retransmits = tcp_sk->icsk_retransmits; |
| 57 | |
| 58 | return 1; |
| 59 | } |
| 60 |