linux/net/dccp
Gerrit Renker 883ca833e5 dccp: Initialisation and type-checking of feature sysctls
This patch takes care of initialising and type-checking sysctls
related to feature negotiation. Type checking is important since some
of the sysctls now directly impact the feature-negotiation process.

The sysctls are initialised with the known default values for each
feature.  For the type-checking the value constraints from RFC 4340
are used:

 * Sequence Window uses the specified Wmin=32, the maximum is ulong (4 bytes),
   tested and confirmed that it works up to 4294967295 - for Gbps speed;
 * Ack Ratio is between 0 .. 0xffff (2-byte unsigned integer);
 * CCIDs are between 0 .. 255;
 * request_retries, retries1, retries2 also between 0..255 for good measure;
 * tx_qlen is checked to be non-negative;
 * sync_ratelimit remains as before.

Notes:
------
 1. Die s@sysctl_dccp_feat@sysctl_dccp@g since the sysctls are now in feat.c.
 2. As pointed out by Arnaldo, the pattern of type-checking repeats itself in
    other places, sometimes with exactly the same kind of definitions (e.g.
    "static int zero;"). It may be a good idea (kernel janitors?) to consolidate
    type checking. For the sake of keeping the changeset small and in order not
    to affect other subsystems, I have not strived to generalise here.

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>
2009-01-21 14:34:05 -08:00
..
ccids dccp ccid-3: Fix RFC reference 2009-01-11 00:17:22 -08:00
ackvec.c dccp: Set per-connection CCIDs via socket options 2008-11-23 16:02:31 -08:00
ackvec.h dccp: Clean up ccid.c after integration of CCID plugins 2009-01-04 21:43:23 -08:00
ccid.c dccp: Integrate the TFRC library with DCCP 2009-01-04 21:45:33 -08:00
ccid.h dccp: Clean up ccid.c after integration of CCID plugins 2009-01-04 21:43:23 -08:00
dccp.h dccp: Initialisation and type-checking of feature sysctls 2009-01-21 14:34:05 -08:00
diag.c dccp_diag: LISTEN sockets don't have CCIDs 2008-12-17 16:08:01 -08:00
feat.c dccp: Initialisation and type-checking of feature sysctls 2009-01-21 14:34:05 -08:00
feat.h dccp: Initialisation and type-checking of feature sysctls 2009-01-21 14:34:05 -08:00
input.c dccp: Integrate the TFRC library with DCCP 2009-01-04 21:45:33 -08:00
ipv4.c net: Convert TCP & DCCP hash tables to use RCU / hlist_nulls 2008-11-16 19:40:17 -08:00
ipv6.c netns xfrm: lookup in netns 2008-11-25 17:35:18 -08:00
ipv6.h Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
Kconfig dccp: Lockless integration of CCID congestion-control plugins 2009-01-04 21:42:53 -08:00
Makefile dccp: Integrate the TFRC library with DCCP 2009-01-04 21:45:33 -08:00
minisocks.c dccp: Implement both feature-local and feature-remote Sequence Window feature 2009-01-21 14:34:04 -08:00
options.c dccp: Initialisation and type-checking of feature sysctls 2009-01-21 14:34:05 -08:00
output.c dccp: use roundup instead of opencoding 2008-12-05 22:39:49 -08:00
probe.c dccp: API to query the current TX/RX CCID 2008-11-23 16:04:59 -08:00
proto.c dccp: Implement both feature-local and feature-remote Sequence Window feature 2009-01-21 14:34:04 -08:00
sysctl.c dccp: Initialisation and type-checking of feature sysctls 2009-01-21 14:34:05 -08:00
timer.c dccp: Limit feature negotiation to connection setup phase 2008-11-12 00:42:58 -08:00