From: Patrick McHardy <kaber@trash.net>
To: KOVACS Krisztian <hidden@sch.bme.hu>
Cc: netfilter-devel@vger.kernel.org,
Balazs Scheidler <bazsi@balabit.hu>,
Toth Laszlo Attila <panther@balabit.hu>
Subject: Re: [PATCH 05/13] Handle TCP SYN+ACK/ACK/RST transparency
Date: Mon, 01 Oct 2007 00:23:14 +0200 [thread overview]
Message-ID: <470021D2.7030002@trash.net> (raw)
In-Reply-To: <20070930205233.10969.32752.stgit@nessa.odu>
KOVACS Krisztian wrote:
> The TCP stack sends out SYN+ACK/ACK/RST reply packets in response to
> incoming packets. The non-local source address check on output bites
> us again, as replies for transparently redirected traffic won't have a
> chance to leave the node.
>
> This patch selectively sets the FLOWI_FLAG_ANYSRC flag when doing
> the route lookup for those replies. Transparent replies are enabled if
> the listening socket has the transparent socket flag set.
>
> Signed-off-by: KOVACS Krisztian <hidden@sch.bme.hu>
> ---
>
> diff --git a/include/net/request_sock.h b/include/net/request_sock.h
> index 7aed02c..b9c8974 100644
> --- a/include/net/request_sock.h
> +++ b/include/net/request_sock.h
> @@ -34,7 +34,8 @@ struct request_sock_ops {
> struct request_sock *req,
> struct dst_entry *dst);
> void (*send_ack)(struct sk_buff *skb,
> - struct request_sock *req);
> + struct request_sock *req,
> + int reply_flags);
>
How about putting the flags in the request_sock?
> diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
> index fbe7714..26b9dbe 100644
> --- a/net/ipv4/inet_connection_sock.c
> +++ b/net/ipv4/inet_connection_sock.c
> @@ -321,6 +321,8 @@ struct dst_entry* inet_csk_route_req(struct sock *sk,
> .saddr = ireq->loc_addr,
> .tos = RT_CONN_FLAGS(sk) } },
> .proto = sk->sk_protocol,
> + .flags = inet_sk(sk)->transparent ?
> + FLOWI_FLAG_ANYSRC : 0,
>
Introducing a function (sk_flowi_flags(sk) or something) might make
it a bit nicer to look at.
> diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
> index e089a97..7ae47e6 100644
> --- a/net/ipv4/tcp_ipv4.c
> +++ b/net/ipv4/tcp_ipv4.c
> @@ -625,7 +626,7 @@ static void tcp_v4_send_reset(struct sock *sk, struct sk_buff *skb)
>
> static void tcp_v4_send_ack(struct tcp_timewait_sock *twsk,
> struct sk_buff *skb, u32 seq, u32 ack,
> - u32 win, u32 ts)
> + u32 win, u32 ts, int reply_flags)
> {
> struct tcphdr *th = tcp_hdr(skb);
> struct {
> @@ -701,36 +702,37 @@ static void tcp_v4_send_ack(struct tcp_timewait_sock *twsk,
> arg.iov[0].iov_len);
> }
> #endif
> + arg.flags = reply_flags;
>
Shouldn't this use twsk->transparent?
> arg.csum = csum_tcpudp_nofold(ip_hdr(skb)->daddr,
> ip_hdr(skb)->saddr, /* XXX */
> arg.iov[0].iov_len, IPPROTO_TCP, 0);
> arg.csumoffset = offsetof(struct tcphdr, check) / 2;
> if (twsk)
> arg.bound_dev_if = twsk->tw_sk.tw_bound_dev_if;
> -
> ip_send_reply(tcp_socket->sk, skb, &arg, arg.iov[0].iov_len);
Unrelated whitespace change
next prev parent reply other threads:[~2007-09-30 22:26 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-09-30 20:51 [PATCH 00/13] Transparent Proxying Patches, Take 3 KOVACS Krisztian
2007-09-30 20:51 ` [PATCH 01/13] Loosen source address check on IPv4 output KOVACS Krisztian
2007-09-30 22:12 ` Patrick McHardy
2007-09-30 20:52 ` [PATCH 02/13] Implement IP_TRANSPARENT socket option KOVACS Krisztian
2007-09-30 22:12 ` Patrick McHardy
2007-09-30 20:52 ` [PATCH 03/13] Allow binding to non-local addresses if IP_TRANSPARENT is set KOVACS Krisztian
2007-09-30 22:12 ` Patrick McHardy
2007-09-30 20:52 ` [PATCH 04/13] Conditionally enable transparent flow flag when connecting KOVACS Krisztian
2007-09-30 20:52 ` [PATCH 05/13] Handle TCP SYN+ACK/ACK/RST transparency KOVACS Krisztian
2007-09-30 21:45 ` Jan Engelhardt
2007-09-30 21:46 ` Jan Engelhardt
2007-09-30 21:59 ` KOVACS Krisztian
2007-09-30 22:02 ` Jan Engelhardt
2007-09-30 21:58 ` KOVACS Krisztian
2007-09-30 22:23 ` Patrick McHardy [this message]
2007-10-01 19:27 ` KOVACS Krisztian
2007-09-30 20:52 ` [PATCH 06/13] Port redirection support for TCP KOVACS Krisztian
2007-09-30 22:26 ` Patrick McHardy
2007-09-30 22:49 ` KOVACS Krisztian
2007-10-01 14:09 ` Patrick McHardy
2007-10-01 14:24 ` KOVACS Krisztian
2007-09-30 20:52 ` [PATCH 07/13] Export UDP socket lookup function KOVACS Krisztian
2007-09-30 20:53 ` [PATCH 08/13] Split Netfilter IPv4 defragmentation into a separate module KOVACS Krisztian
2007-09-30 22:35 ` Patrick McHardy
2007-09-30 20:53 ` [PATCH 09/13] iptables tproxy core KOVACS Krisztian
2007-09-30 22:37 ` Patrick McHardy
2007-09-30 20:53 ` [PATCH 10/13] iptables socket match KOVACS Krisztian
2007-09-30 21:43 ` Jan Engelhardt
2007-09-30 22:15 ` [PATCH 10/13] xt_socket Jan Engelhardt
2007-09-30 20:53 ` [PATCH 11/13] iptables TPROXY target KOVACS Krisztian
2007-09-30 21:40 ` [PATCH 11/13] xtables " Jan Engelhardt
2007-09-30 22:07 ` KOVACS Krisztian
2007-09-30 22:20 ` [PATCH 11/13] xt_TPROXY Jan Engelhardt
2007-09-30 23:04 ` KOVACS Krisztian
2007-09-30 22:43 ` [PATCH 11/13] iptables TPROXY target Patrick McHardy
2007-09-30 22:50 ` Jan Engelhardt
2007-09-30 22:51 ` KOVACS Krisztian
2007-09-30 22:56 ` Patrick McHardy
2007-09-30 23:06 ` KOVACS Krisztian
2007-09-30 22:57 ` Jan Engelhardt
2007-10-01 14:11 ` Patrick McHardy
2007-09-30 20:53 ` [PATCH 12/13] Don't lookup the socket if there's a socket attached to the skb KOVACS Krisztian
2007-09-30 20:53 ` [PATCH 13/13] " KOVACS Krisztian
2007-09-30 22:01 ` [PATCH 00/13] Transparent Proxying Patches, Take 3 Patrick McHardy
2007-09-30 22:13 ` KOVACS Krisztian
-- strict thread matches above, loose matches on Subject: below --
2007-10-02 20:39 [PATCH 00/13] Transparent Proxying Patches, Take 4 KOVACS Krisztian
2007-10-02 20:42 ` [PATCH 05/13] Handle TCP SYN+ACK/ACK/RST transparency KOVACS Krisztian
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