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| author | Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> | 2009-03-14 14:23:03 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2009-03-15 20:09:52 -0700 |
| commit | c887e6d2d9aee56ee7c9f2af4cec3a5efdcc4c72 (patch) | |
| tree | ee267baadce309166ceea5649292f221cd9a6766 /net/ipv4 | |
| parent | c43d558a5139a3b22dcac3f19f64ecb39130b02e (diff) | |
| download | linux-3.10-c887e6d2d9aee56ee7c9f2af4cec3a5efdcc4c72.tar.gz linux-3.10-c887e6d2d9aee56ee7c9f2af4cec3a5efdcc4c72.tar.bz2 linux-3.10-c887e6d2d9aee56ee7c9f2af4cec3a5efdcc4c72.zip | |
tcp: consolidate paws check
Wow, it was quite tricky to merge that stream of negations
but I think I finally got it right:
check & replace_ts_recent:
(s32)(rcv_tsval - ts_recent) >= 0 => 0
(s32)(ts_recent - rcv_tsval) <= 0 => 0
discard:
(s32)(ts_recent - rcv_tsval) > TCP_PAWS_WINDOW => 1
(s32)(ts_recent - rcv_tsval) <= TCP_PAWS_WINDOW => 0
I toggled the return values of tcp_paws_check around since
the old encoding added yet-another negation making tracking
of truth-values really complicated.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/tcp_input.c | 11 | ||||
| -rw-r--r-- | net/ipv4/tcp_minisocks.c | 4 |
2 files changed, 7 insertions, 8 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index f527a16a7b3..b7d02c5dd6d 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -3883,8 +3883,7 @@ static inline void tcp_replace_ts_recent(struct tcp_sock *tp, u32 seq) * Not only, also it occurs for expired timestamps. */ - if ((s32)(tp->rx_opt.rcv_tsval - tp->rx_opt.ts_recent) >= 0 || - get_seconds() >= tp->rx_opt.ts_recent_stamp + TCP_PAWS_24DAYS) + if (tcp_paws_check(&tp->rx_opt, 0)) tcp_store_ts_recent(tp); } } @@ -3936,9 +3935,9 @@ static inline int tcp_paws_discard(const struct sock *sk, const struct sk_buff *skb) { const struct tcp_sock *tp = tcp_sk(sk); - return ((s32)(tp->rx_opt.ts_recent - tp->rx_opt.rcv_tsval) > TCP_PAWS_WINDOW && - get_seconds() < tp->rx_opt.ts_recent_stamp + TCP_PAWS_24DAYS && - !tcp_disordered_ack(sk, skb)); + + return !tcp_paws_check(&tp->rx_opt, TCP_PAWS_WINDOW) && + !tcp_disordered_ack(sk, skb); } /* Check segment sequence number for validity. @@ -5513,7 +5512,7 @@ discard: /* PAWS check. */ if (tp->rx_opt.ts_recent_stamp && tp->rx_opt.saw_tstamp && - tcp_paws_check(&tp->rx_opt, 0)) + tcp_paws_reject(&tp->rx_opt, 0)) goto discard_and_undo; if (th->syn) { diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c index 4b0df3e6b60..43bbba7926e 100644 --- a/net/ipv4/tcp_minisocks.c +++ b/net/ipv4/tcp_minisocks.c @@ -107,7 +107,7 @@ tcp_timewait_state_process(struct inet_timewait_sock *tw, struct sk_buff *skb, if (tmp_opt.saw_tstamp) { tmp_opt.ts_recent = tcptw->tw_ts_recent; tmp_opt.ts_recent_stamp = tcptw->tw_ts_recent_stamp; - paws_reject = tcp_paws_check(&tmp_opt, th->rst); + paws_reject = tcp_paws_reject(&tmp_opt, th->rst); } } @@ -511,7 +511,7 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, * from another data. */ tmp_opt.ts_recent_stamp = get_seconds() - ((TCP_TIMEOUT_INIT/HZ)<<req->retrans); - paws_reject = tcp_paws_check(&tmp_opt, th->rst); + paws_reject = tcp_paws_reject(&tmp_opt, th->rst); } } |