| 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 | } |
|---|
| 89 | |
|---|
