diff options
Diffstat (limited to 'include/net/tcp_ao.h')
| -rw-r--r-- | include/net/tcp_ao.h | 22 |
1 files changed, 21 insertions, 1 deletions
diff --git a/include/net/tcp_ao.h b/include/net/tcp_ao.h index cfb55bd9411b..0c3516d1b968 100644 --- a/include/net/tcp_ao.h +++ b/include/net/tcp_ao.h @@ -95,6 +95,25 @@ struct tcp_ao_info { __unused :31; __be32 lisn; __be32 risn; + /* Sequence Number Extension (SNE) are upper 4 bytes for SEQ, + * that protect TCP-AO connection from replayed old TCP segments. + * See RFC5925 (6.2). + * In order to get correct SNE, there's a helper tcp_ao_compute_sne(). + * It needs SEQ basis to understand whereabouts are lower SEQ numbers. + * According to that basis vector, it can provide incremented SNE + * when SEQ rolls over or provide decremented SNE when there's + * a retransmitted segment from before-rolling over. + * - for request sockets such basis is rcv_isn/snt_isn, which seems + * good enough as it's unexpected to receive 4 Gbytes on reqsk. + * - for full sockets the basis is rcv_nxt/snd_una. snd_una is + * taken instead of snd_nxt as currently it's easier to track + * in tcp_snd_una_update(), rather than updating SNE in all + * WRITE_ONCE(tp->snd_nxt, ...) + * - for time-wait sockets the basis is tw_rcv_nxt/tw_snd_nxt. + * tw_snd_nxt is not expected to change, while tw_rcv_nxt may. + */ + u32 snd_sne; + u32 rcv_sne; refcount_t refcnt; /* Protects twsk destruction */ struct rcu_head rcu; }; @@ -147,6 +166,7 @@ enum skb_drop_reason tcp_inbound_ao_hash(struct sock *sk, const struct sk_buff *skb, unsigned short int family, const struct request_sock *req, const struct tcp_ao_hdr *aoh); +u32 tcp_ao_compute_sne(u32 next_sne, u32 next_seq, u32 seq); struct tcp_ao_key *tcp_ao_do_lookup(const struct sock *sk, const union tcp_ao_addr *addr, int family, int sndid, int rcvid); @@ -156,7 +176,7 @@ int tcp_ao_hash_hdr(unsigned short family, char *ao_hash, const union tcp_ao_addr *saddr, const struct tcphdr *th, u32 sne); int tcp_ao_prepare_reset(const struct sock *sk, struct sk_buff *skb, - const struct tcp_ao_hdr *aoh, int l3index, + const struct tcp_ao_hdr *aoh, int l3index, u32 seq, struct tcp_ao_key **key, char **traffic_key, bool *allocated_traffic_key, u8 *keyid, u32 *sne); |