Commit Graph

11 Commits

Author SHA1 Message Date
Arnaldo Carvalho de Melo a693722aec dccp_diag: LISTEN sockets don't have CCIDs
And thus when we try to use 'ss -danemi' on these sockets that have no
ccid blocks (data collected using systemtap after I fixed the problem):

dccp_diag_get_info sk=0xffff8801220a3100, dp->dccps_hc_rx_ccid=0x0000000000000000, dp->dccps_hc_tx_ccid=0x0000000000000000

We get an OOPS:

mica.ghostprotocols.net login: BUG: unable to handle kernel NULL pointer
dereferenc0
IP: [<ffffffffa0136082>] dccp_diag_get_info+0x82/0xc0 [dccp_diag]
PGD 12106f067 PUD 122488067 PMD 0
Oops: 0000 [#1] PREEMPT

Fix is trivial, and 'ss -d' is working again:

[root@mica ~]# ss -danemi
State   Recv-Q Send-Q   Local Address:Port   Peer Address:Port 
LISTEN  0      0                    *:5001              *:*
ino:7288 sk:220a3100ffff8801
	 mem:(r0,w0,f0,t0) cwnd:0 ssthresh:0
[root@mica ~]# 

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-17 16:08:01 -08:00
Gerrit Renker 6fdd34d43b dccp ccid-2: Phase out the use of boolean Ack Vector sysctl
This removes the use of the sysctl and the minisock variable for the Send Ack
Vector feature, as it now is handled fully dynamically via feature negotiation
(i.e. when CCID-2 is enabled, Ack Vectors are automatically enabled as per
 RFC 4341, 4.).

Using a sysctl in parallel to this implementation would open the door to
crashes, since much of the code relies on tests of the boolean minisock /
sysctl variable. Thus, this patch replaces all tests of type

	if (dccp_msk(sk)->dccpms_send_ack_vector)
		/* ... */
with
	if (dp->dccps_hc_rx_ackvec != NULL)
		/* ... */

The dccps_hc_rx_ackvec is allocated by the dccp_hdlr_ackvec() when feature
negotiation concluded that Ack Vectors are to be used on the half-connection.
Otherwise, it is NULL (due to dccp_init_sock/dccp_create_openreq_child),
so that the test is a valid one.

The activation handler for Ack Vectors is called as soon as the feature
negotiation has concluded at the
 * server when the Ack marking the transition RESPOND => OPEN arrives;
 * client after it has sent its ACK, marking the transition REQUEST => PARTOPEN.

Adding the sequence number of the Response packet to the Ack Vector has been
removed, since
 (a) connection establishment implies that the Response has been received;
 (b) the CCIDs only look at packets received in the (PART)OPEN state, i.e.
     this entry will always be ignored;
 (c) it can not be used for anything useful - to detect loss for instance, only
     packets received after the loss can serve as pseudo-dupacks.

There was a FIXME to change the error code when dccp_ackvec_add() fails.
I removed this after finding out that:
 * the check whether ackno < ISN is already made earlier,
 * this Response is likely the 1st packet with an Ackno that the client gets,
 * so when dccp_ackvec_add() fails, the reason is likely not a packet error.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-08 01:19:06 -08:00
Eric Dumazet a7a0d6a87b net: inet_diag_handler structs can be const
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-19 15:43:27 -08:00
Jean Delvare 305e1e9691 [INET]: Let inet_diag and friends autoload
By adding module aliases to inet_diag, tcp_diag and dccp_diag, we let
them load automatically as needed. This makes tools like "ss" run
faster.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-22 02:59:54 -07:00
Jörn Engel 6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Arnaldo Carvalho de Melo a4bf390242 [DCCP] minisock: Rename struct dccp_options to struct dccp_minisock
This will later be included in struct dccp_request_sock so that we can
have per connection feature negotiation state while in the 3way
handshake, when we clone the DCCP_ROLE_LISTEN socket (in
dccp_create_openreq_child) we'll just copy this state from
dreq_minisock to dccps_minisock.

Also the feature negotiation and option parsing code will mostly touch
dccps_minisock, which will simplify some stuff.

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 22:50:58 -08:00
Arnaldo Carvalho de Melo d83d8461f9 [IP_SOCKGLUE]: Remove most of the tcp specific calls
As DCCP needs to be called in the same spots.

Now we have a member in inet_sock (is_icsk), set at sock creation time from
struct inet_protosw->flags (if INET_PROTOSW_ICSK is set, like for TCP and
DCCP) to see if a struct sock instance is a inet_connection_sock for places
like the ones in ip_sockglue.c (v4 and v6) where we previously were looking if
sk_type was SOCK_STREAM, that is insufficient because we now use the same code
for DCCP, that has sk_type SOCK_DCCP.

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03 13:10:58 -08:00
Arnaldo Carvalho de Melo 2babe1f6fe [DCCP]: Introduce dccp_get_info
And also hc_tx and hc_rx get_info functions for the CCIDs to fill in
information that is specific to them.

For now reusing struct tcp_info, later I'll try to figure out a better
solution, for now its really nice to get this kind of info:

[root@qemu ~]# ./ss -danemi
State       Recv-Q Send-Q  Local Addr:Port  Peer Addr:Port
LISTEN      0      0                *:5001          *:*     ino:628 sk:c1340040
         mem:(r0,w0,f0,t0) cwnd:0 ssthresh:0
ESTAB       0      0       172.20.0.2:5001 172.20.0.1:32785 ino:629 sk:c13409a0
         mem:(r0,w0,f0,t0) ts rto:1000 rtt:0.004/0 cwnd:0 ssthresh:0 rcv_rtt:61.377

This, for instance, shows that we're not congestion controlling ACKs,
as the above output is in the ttcp receiving host, and ttcp is a one
way app, i.e. the received never calls sendmsg, so
ccid_hc_tx_send_packet is never called, so the TX half connection
stays in TFRC_SSTATE_NO_SENT state and hctx_rtt is never calculated,
stays with the value set in ccid3_hc_tx_init, 4us, as show above in
milliseconds (0.004ms), upcoming patches will fix this.

rcv_rtt seems sane tho, matching ping results :-)

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29 16:05:07 -07:00
Arnaldo Carvalho de Melo a8c2190ee7 [INET_DIAG]: Rename tcp_diag.[ch] to inet_diag.[ch]
Next changeset will introduce net/ipv4/tcp_diag.c, moving the code that was put
transitioanlly in inet_diag.c.

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29 15:57:48 -07:00
Arnaldo Carvalho de Melo 73c1f4a033 [TCPDIAG]: Just rename everything to inet_diag
Next changeset will rename tcp_diag.[ch] to inet_diag.[ch].

I'm taking this longer route so as to easy review, making clear the changes
made all along the way.

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29 15:57:44 -07:00
Arnaldo Carvalho de Melo 4f5736c4c7 [TCPDIAG]: Introduce inet_diag_{register,unregister}
Next changeset will rename tcp_diag to inet_diag and move the tcp_diag code out
of it and into a new tcp_diag.c, similar to the net/dccp/diag.c introduced in
this changeset, completing the transition to a generic inet_diag
infrastructure.

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29 15:57:38 -07:00