Current TCP code relies on the local port of the listening socket being the same as the destination address of the incoming connection. Port redirection used by many transparent proxying techniques obviously breaks this, so we have to store the original destination port address.
This patch extends struct inet_request_sock and stores the incoming destination port value there. It also modifies the handshake code to use that value as the source port when sending reply packets. Signed-off-by: KOVACS Krisztian <[EMAIL PROTECTED]> --- include/net/inet_sock.h | 1 + include/net/tcp.h | 1 + net/ipv4/inet_connection_sock.c | 2 ++ net/ipv4/tcp_output.c | 2 +- 4 files changed, 5 insertions(+), 1 deletions(-) diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h index ce6da97..0bd167b 100644 --- a/include/net/inet_sock.h +++ b/include/net/inet_sock.h @@ -64,6 +64,7 @@ #if defined(CONFIG_IPV6) || defined(CONF #endif __be32 loc_addr; __be32 rmt_addr; + __be16 loc_port; __be16 rmt_port; u16 snd_wscale : 4, rcv_wscale : 4, diff --git a/include/net/tcp.h b/include/net/tcp.h index b7d8317..08ea8f3 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -983,6 +983,7 @@ static inline void tcp_openreq_init(stru ireq->acked = 0; ireq->ecn_ok = 0; ireq->rmt_port = skb->h.th->source; + ireq->loc_port = skb->h.th->dest; } extern void tcp_enter_memory_pressure(void); diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c index 9d68837..889a487 100644 --- a/net/ipv4/inet_connection_sock.c +++ b/net/ipv4/inet_connection_sock.c @@ -502,6 +502,8 @@ struct sock *inet_csk_clone(struct sock newicsk->icsk_bind_hash = NULL; inet_sk(newsk)->dport = inet_rsk(req)->rmt_port; + inet_sk(newsk)->num = ntohs(inet_rsk(req)->loc_port); + inet_sk(newsk)->sport = inet_rsk(req)->loc_port; newsk->sk_write_space = sk_stream_write_space; newicsk->icsk_retransmits = 0; diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 32c1a97..bb37048 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -2132,7 +2132,7 @@ #endif th->syn = 1; th->ack = 1; TCP_ECN_make_synack(req, th); - th->source = inet_sk(sk)->sport; + th->source = ireq->loc_port; th->dest = ireq->rmt_port; TCP_SKB_CB(skb)->seq = tcp_rsk(req)->snt_isn; TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(skb)->seq + 1; - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html