linux-toradex.git/net/ipv6/syncookies.c, branch v3.2.40

tcp: add const qualifiers where possible

2011-10-21T09:22:42+00:00

Adding const qualifiers to pointers can ease code review, and spot some
bugs. It might allow compiler to optimize code further.

For example, is it legal to temporary write a null cksum into tcphdr
in tcp_md5_hash_header() ? I am afraid a sniffer could catch the
temporary null value...

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

tcp: initialize variable ecn_ok in syncookies path

2011-08-11T04:59:57+00:00

Using a gcc 4.4.3, warnings are emitted for a possibly uninitialized use
of ecn_ok.

This can happen if cookie_check_timestamp() returns due to not having
seen a timestamp.  Defaulting to ecn off seems like a reasonable thing
to do in this case, so initialized ecn_ok to false.

Signed-off-by: Mike Waychison 
Signed-off-by: David S. Miller

tcp: RFC2988bis + taking RTT sample from 3WHS for the passive open side

2011-06-09T00:05:30+00:00

This patch lowers the default initRTO from 3secs to 1sec per
RFC2988bis. It falls back to 3secs if the SYN or SYN-ACK packet
has been retransmitted, AND the TCP timestamp option is not on.

It also adds support to take RTT sample during 3WHS on the passive
open side, just like its active open counterpart, and uses it, if
valid, to seed the initRTO for the data transmission phase.

The patch also resets ssthresh to its initial default at the
beginning of the data transmission phase, and reduces cwnd to 1 if
there has been MORE THAN ONE retransmission during 3WHS per RFC5681.

Signed-off-by: H.K. Jerry Chu 
Signed-off-by: David S. Miller

inet: constify ip headers and in6_addr

2011-04-22T18:04:14+00:00

Add const qualifiers to structs iphdr, ipv6hdr and in6_addr pointers
where possible, to make code intention more obvious.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

net: Put fl6_* macros to struct flowi6 and use them again.

2011-03-12T23:08:55+00:00

Signed-off-by: David S. Miller

ipv6: Convert to use flowi6 where applicable.

2011-03-12T23:08:54+00:00

Signed-off-by: David S. Miller

net: Make flowi ports AF dependent.

2011-03-12T23:08:46+00:00

Create two sets of port member accessors, one set prefixed by fl4_*
and the other prefixed by fl6_*

This will let us to create AF optimal flow instances.

It will work because every context in which we access the ports,
we have to be fully aware of which AF the flowi is anyways.

Signed-off-by: David S. Miller

net: Put flowi_* prefix on AF independent members of struct flowi

2011-03-12T23:08:44+00:00

I intend to turn struct flowi into a union of AF specific flowi
structs.  There will be a common structure that each variant includes
first, much like struct sock_common.

This is the first step to move in that direction.

Signed-off-by: David S. Miller

ipv6: Consolidate route lookup sequences.

2011-03-01T21:19:07+00:00

Route lookups follow a general pattern in the ipv6 code wherein
we first find the non-IPSEC route, potentially override the
flow destination address due to ipv6 options settings, and then
finally make an IPSEC search using either xfrm_lookup() or
__xfrm_lookup().

__xfrm_lookup() is used when we want to generate a blackhole route
if the key manager needs to resolve the IPSEC rules (in this case
-EREMOTE is returned and the original 'dst' is left unchanged).

Otherwise plain xfrm_lookup() is used and when asynchronous IPSEC
resolution is necessary, we simply fail the lookup completely.

All of these cases are encapsulated into two routines,
ip6_dst_lookup_flow and ip6_sk_dst_lookup_flow.  The latter of which
handles unconnected UDP datagram sockets.

Signed-off-by: David S. Miller

syncookies: add support for ECN

2010-06-27T05:00:03+00:00

Allows use of ECN when syncookies are in effect by encoding ecn_ok
into the syn-ack tcp timestamp.

While at it, remove a uneeded #ifdef CONFIG_SYN_COOKIES.
With CONFIG_SYN_COOKIES=nm want_cookie is ifdef'd to 0 and gcc
removes the "if (0)".

Signed-off-by: Florian Westphal 
Signed-off-by: David S. Miller