[PATCH v4 14/21] net/tcp: Add TCP-AO SNE support
From: Dmitry Safonov <hidden>
Date: 2023-02-15 18:36:04
Also in:
lkml
Subsystem:
networking [general], networking [tcp], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Neal Cardwell, Linus Torvalds
Add Sequence Number Extension (SNE) extension for TCP-AO. This is needed to protect long-living TCP-AO connections from replaying attacks after sequence number roll-over, see RFC5925 (6.2). Co-developed-by: Francesco Ruggeri <redacted> Signed-off-by: Francesco Ruggeri <redacted> Co-developed-by: Salam Noureddine <redacted> Signed-off-by: Salam Noureddine <redacted> Signed-off-by: Dmitry Safonov <redacted> --- net/ipv4/tcp_input.c | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+)
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 264db761153b..9f23cab1e835 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c@@ -3528,9 +3528,21 @@ static inline bool tcp_may_update_window(const struct tcp_sock *tp, static void tcp_snd_una_update(struct tcp_sock *tp, u32 ack) { u32 delta = ack - tp->snd_una; +#ifdef CONFIG_TCP_AO + struct tcp_ao_info *ao; +#endif sock_owned_by_me((struct sock *)tp); tp->bytes_acked += delta; +#ifdef CONFIG_TCP_AO + ao = rcu_dereference_protected(tp->ao_info, + lockdep_sock_is_held((struct sock *)tp)); + if (ao) { + if (ack < ao->snd_sne_seq) + ao->snd_sne++; + ao->snd_sne_seq = ack; + } +#endif tp->snd_una = ack; }
@@ -3538,9 +3550,21 @@ static void tcp_snd_una_update(struct tcp_sock *tp, u32 ack) static void tcp_rcv_nxt_update(struct tcp_sock *tp, u32 seq) { u32 delta = seq - tp->rcv_nxt; +#ifdef CONFIG_TCP_AO + struct tcp_ao_info *ao; +#endif sock_owned_by_me((struct sock *)tp); tp->bytes_received += delta; +#ifdef CONFIG_TCP_AO + ao = rcu_dereference_protected(tp->ao_info, + lockdep_sock_is_held((struct sock *)tp)); + if (ao) { + if (seq < ao->rcv_sne_seq) + ao->rcv_sne++; + ao->rcv_sne_seq = seq; + } +#endif WRITE_ONCE(tp->rcv_nxt, seq); }
@@ -6369,6 +6393,17 @@ static int tcp_rcv_synsent_state_process(struct sock *sk, struct sk_buff *skb, * simultaneous connect with crossed SYNs. * Particularly, it can be connect to self. */ +#ifdef CONFIG_TCP_AO + struct tcp_ao_info *ao; + + ao = rcu_dereference_protected(tp->ao_info, + lockdep_sock_is_held(sk)); + if (ao) { + ao->risn = th->seq; + ao->rcv_sne = 0; + ao->rcv_sne_seq = ntohl(th->seq); + } +#endif tcp_set_state(sk, TCP_SYN_RECV); if (tp->rx_opt.saw_tstamp) {
--
2.39.1