diff options
| author | Kuniyuki Iwashima <kuniyu@amazon.com> | 2024-01-15 12:55:12 -0800 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2024-01-23 14:40:24 -0800 |
| commit | 695751e31a63efd2bbe6779873adf1e4deb00cd5 (patch) | |
| tree | 41904868bb6f47e98aa75ab19e148d03c52514a2 /net/ipv6 | |
| parent | 8b5ac68fb5ee416537c1214cbacf0ddc4293cce9 (diff) | |
| download | linux-695751e31a63efd2bbe6779873adf1e4deb00cd5.tar.gz | |
bpf: tcp: Handle BPF SYN Cookie in cookie_v[46]_check().
We will support arbitrary SYN Cookie with BPF in the following
patch.
If BPF prog validates ACK and kfunc allocates a reqsk, it will
be carried to cookie_[46]_check() as skb->sk. If skb->sk is not
NULL, we call cookie_bpf_check().
Then, we clear skb->sk and skb->destructor, which are needed not
to hold refcnt for reqsk and the listener. See the following patch
for details.
After that, we finish initialisation for the remaining fields with
cookie_tcp_reqsk_init().
Note that the server side WScale is set only for non-BPF SYN Cookie.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20240115205514.68364-5-kuniyu@amazon.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'net/ipv6')
| -rw-r--r-- | net/ipv6/syncookies.c | 13 |
1 files changed, 9 insertions, 4 deletions
diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c index c8d2ca27220cc..6b9c692788196 100644 --- a/net/ipv6/syncookies.c +++ b/net/ipv6/syncookies.c @@ -182,9 +182,13 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb) !th->ack || th->rst) goto out; - req = cookie_tcp_check(net, sk, skb); - if (IS_ERR(req)) - goto out; + if (cookie_bpf_ok(skb)) { + req = cookie_bpf_check(sk, skb); + } else { + req = cookie_tcp_check(net, sk, skb); + if (IS_ERR(req)) + goto out; + } if (!req) goto out_drop; @@ -247,7 +251,8 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb) ireq->wscale_ok, &rcv_wscale, dst_metric(dst, RTAX_INITRWND)); - ireq->rcv_wscale = rcv_wscale; + if (!req->syncookie) + ireq->rcv_wscale = rcv_wscale; ireq->ecn_ok &= cookie_ecn_ok(net, dst); ret = tcp_get_cookie_sock(sk, skb, req, dst); |