[DCCP] feat: Introduce sysctls for the default features

[root@qemu ~]# for a in /proc/sys/net/dccp/default/* ; do echo $a ; cat $a ; done
/proc/sys/net/dccp/default/ack_ratio
2
/proc/sys/net/dccp/default/rx_ccid
3
/proc/sys/net/dccp/default/send_ackvec
1
/proc/sys/net/dccp/default/send_ndp
1
/proc/sys/net/dccp/default/seq_window
100
/proc/sys/net/dccp/default/tx_ccid
3
[root@qemu ~]#

So if wanting to test ccid3 as the tx CCID one can just do:

[root@qemu ~]# echo 3 > /proc/sys/net/dccp/default/tx_ccid
[root@qemu ~]# echo 2 > /proc/sys/net/dccp/default/rx_ccid
[root@qemu ~]# cat /proc/sys/net/dccp/default/[tr]x_ccid
2
3
[root@qemu ~]#

Of course we also need the setsockopt for each app to tell its preferences, but
for testing or defining something other than CCID2 as the default for apps that
don't explicitely set their preference the sysctl interface is handy.

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 12 insertions, 10 deletions

diff --git a/net/dccp/options.c b/net/dccp/options.c
index 7d73b33..3ecd319 100644
--- a/net/dccp/options.c
+++ b/net/dccp/options.c
@@ -23,19 +23,21 @@
 #include "dccp.h"
 #include "feat.h"
 
-/* stores the default values for new connection. may be changed with sysctl */
-static const struct dccp_options dccpo_default_values = {
-	.dccpo_sequence_window	  = DCCPF_INITIAL_SEQUENCE_WINDOW,
-	.dccpo_rx_ccid		  = DCCPF_INITIAL_CCID,
-	.dccpo_tx_ccid		  = DCCPF_INITIAL_CCID,
-	.dccpo_ack_ratio	  = DCCPF_INITIAL_ACK_RATIO,
-	.dccpo_send_ack_vector	  = DCCPF_INITIAL_SEND_ACK_VECTOR,
-	.dccpo_send_ndp_count	  = DCCPF_INITIAL_SEND_NDP_COUNT,
-};
+int dccp_feat_default_sequence_window = DCCPF_INITIAL_SEQUENCE_WINDOW;
+int dccp_feat_default_rx_ccid	      = DCCPF_INITIAL_CCID;
+int dccp_feat_default_tx_ccid	      = DCCPF_INITIAL_CCID;
+int dccp_feat_default_ack_ratio	      = DCCPF_INITIAL_ACK_RATIO;
+int dccp_feat_default_send_ack_vector = DCCPF_INITIAL_SEND_ACK_VECTOR;
+int dccp_feat_default_send_ndp_count  = DCCPF_INITIAL_SEND_NDP_COUNT;
 
 void dccp_options_init(struct dccp_options *dccpo)
 {
-	memcpy(dccpo, &dccpo_default_values, sizeof(*dccpo));
+	dccpo->dccpo_sequence_window = dccp_feat_default_sequence_window;
+	dccpo->dccpo_rx_ccid	     = dccp_feat_default_rx_ccid;
+	dccpo->dccpo_tx_ccid	     = dccp_feat_default_tx_ccid;
+	dccpo->dccpo_ack_ratio	     = dccp_feat_default_ack_ratio;
+	dccpo->dccpo_send_ack_vector = dccp_feat_default_send_ack_vector;
+	dccpo->dccpo_send_ndp_count  = dccp_feat_default_send_ndp_count;
 }
 
 static u32 dccp_decode_value_var(const unsigned char *bf, const u8 len)