This updates sequence number checking with regard to RFC 4340, 7.5.4.
Missing in the code was an exception for sequence-invalid Reset packets,
which get a Sync acknowledging GSR, instead of (as usual) P.seqno.
This can lead to an oscillating ping-pong flood of Reset packets.
In fact, it has been observed on the wire as follows:
1. client establishes connection to server;
2. before server can write to client, client crashes without notifying
the server (NB: now no longer possible due to ABORT function);
3. server sends DCCP-Data packet (has no ackno);
4. client generates Reset "No Connection", seqno=0, increments seqno;
5. server replies with Sync, using ackno = P.seqno;
6. client generates Reset "No Connection" with seqno = ackno + 1;
7. goto (5).
The difference is that now in (5) the server uses GSR. This causes the
Reset sent by the client in (6) to become sequence-valid, so that in (7)
the vicious circle is broken; the Reset is then enqueued and causes the
socket to enter TIMEWAIT state.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is in part required by the next patch; it
* replaces 6 instances of `DCCP_SKB_CB(skb)->dccpd_seq' with `seqno';
* replaces 7 instances of `DCCP_SKB_CB(skb)->dccpd_ack_seq' with `ackno';
* replaces 1 use of dccp_inc_seqno() by unfolding `ADD48' macro in place.
No changes in algorithm, all changes are text replacement/substitution.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The third parameter of dccp_sample_rtt now becomes useless and is removed.
Also combined the subtraction of the timestamp echo and the elapsed time.
This is safe, since (a) presence of timestamp echo is tested first and (b)
elapsed time is either present and non-zero or it is not set and equals 0
due to the memset in dccp_parse_options.
To avoid measuring option-processing time, the timestamp for measuring the
initial Request/Response RTT sample is taken directly when the function is
called (the Linux implementation always adds a timestamp on the Request,
so there is no loss in doing this).
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This provides a timesource, conveniently used for DCCP timestamps, which
returns the elapsed time in 10s of microseconds since initialisation.
This makes for a wrap-around time of about 11.9 hours, which should be
sufficient for most applications.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch reduces the number of timestamps taken in the receive path
for each packet.
The ccid3_hc_tx_update_x() routine is called in
* the receive path for each CCID3-controlled packet
* for the nofeedback timer (if no feedback arrives during 4 RTT)
Currently, when there is no loss, each packet gets timestamped twice.
The patch resolves this by recycling the first timestamp taken on packet
reception for RTT sampling.
When the no_feedback_timer() is called, then the timestamp argument is
simply set to NULL - so that ccid3_hc_tx_update_x() takes care of the logic.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch makes /proc/net per network namespace. It modifies the global
variables proc_net and proc_net_stat to be per network namespace.
The proc_net file helpers are modified to take a network namespace argument,
and all of their callers are fixed to pass &init_net for that argument.
This ensures that all of the /proc/net files are only visible and
usable in the initial network namespace until the code behind them
has been updated to be handle multiple network namespaces.
Making /proc/net per namespace is necessary as at least some files
in /proc/net depend upon the set of network devices which is per
network namespace, and even more files in /proc/net have contents
that are relevant to a single network namespace.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This trivial patch removes the unneeded pointer newdp, which is never used.
Signed-off-by: Micah Gruber <micah.gruber@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Hopefully captured all single statement cases under net/. I'm
not too sure if there is some policy about #includes that are
"guaranteed" (ie., in the current tree) to be available through
some other #included header, so I just added linux/kernel.h to
each changed file that didn't #include it previously.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now to convert the ackvec code to ktime_t so that we can get rid of
dccp_timestamp and the epoch thing in dccp_sock.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The code was too complicated, if p > 0 in ccid3_hc_tx_no_feedback_timer the
timestamp was being obtained to be passed to ccid3_hc_tx_update_x, where only
if p > 0 the timestamp was needed, so just leave it to ccid3_hc_tx_update_x to
obtain the timestamp if needed.
This will help in the upcoming changesets where we'll convert t_ld to ktime_t.
We'll eventually try to reuse ktime_get_real() calls again.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
There's a memory leak in net/dccp/feat.c::dccp_feat_empty_confirm(). If we
hit the 'default:' case of the 'switch' statement, then we return without
freeing 'opt', thus leaking 'struct dccp_opt_pend' bytes.
The leak is fixed easily enough by adding a kfree(opt); before the return
statement.
The patch also changes the layout of the 'switch' to be more in line with
CodingStyle.
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make sure that spin_unlock_wait() is properly ordered wrt atomic_inc().
(akpm: can't we convert this code to use rwlocks?)
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Slab destructors were no longer supported after Christoph's
c59def9f22 change. They've been
BUGs for both slab and slub, and slob never supported them
either.
This rips out support for the dtor pointer from kmem_cache_create()
completely and fixes up every single callsite in the kernel (there were
about 224, not including the slab allocator definitions themselves,
or the documentation references).
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
AFAICT now that jprobe.entry is a void *, JPROBE_ENTRY doesn't do anything
useful - so remove it ..
I've left a do-nothing version so that out-of-tree jprobes code will still
compile without modifications.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Based on <draft-ietf-ipv6-deprecate-rh0-00.txt>.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
ccid3_hc_tx_send_packet currently returns 0 when the time difference between
current time and t_nom is less than 1000 microseconds.
In this case the packet is sent immediately; but, unlike other packets that can
be emitted on first attempt, it will not have its window counter updated and
its options set as required. This is a bug.
Fix: Require the time difference to be at least 1000 microseconds. The
algorithm then converges: time differences > 1000 microseconds trigger the
timer in dccp_write_xmit; after timer expiry this function is tried again; when
the time difference is less than 1000, the packet will have its options added
and window counter updated as required.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
This updates the computation of t_nom and t_last_win_count to use the newer
gettimeofday interface.
Committer note: used ktime_to_timeval to set the 'now' variable to t_ld in
ccid3hctx_no_feedback_timer
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
It had just a slab cache, so, for the sake of simplicity just make
dccp_trfc_lib module init routine create the slab cache, no need for users of
the lib to create a private loss_interval object.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Now ccid3_hc_rx_update_li is ready to be moved to
net/dccp/ccids/lib/loss_interval, it uses the same interface as the other
functions there.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This is a preparatory patch for moving these loss interval functions from
net/dccp/ccids/ccid3.c to net/dccp/ccids/lib/loss_interval.c.
Based on a patch by Ian McDonald.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
When compiling with EXTRA_CFLAGS=-W noticed that tstamp is not initialised
correctly in dccp_li_calc_first_li.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
When compiling with EXTRA_CFLAGS=-W notice that we have signed/unsigned issue
in dccp.h.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Recent gcc versions emit warnings when unsigned variables are
compared < 0 or >= 0.
Signed-off-by: Bill Nottingham <notting@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current IPSEC rule resolution behavior we have does not work for a
lot of people, even though technically it's an improvement from the
-EAGAIN buisness we had before.
Right now we'll block until the key manager resolves the route. That
works for simple cases, but many folks would rather packets get
silently dropped until the key manager resolves the IPSEC rules.
We can't tell these folks to "set the socket non-blocking" because
they don't have control over the non-block setting of things like the
sockets used to resolve DNS deep inside of the resolver libraries in
libc.
With that in mind I coded up the patch below with some help from
Herbert Xu which provides packet-drop behavior during larval state
resolution, controllable via sysctl and off by default.
This lays the framework to either:
1) Make this default at some point or...
2) Move this logic into xfrm{4,6}_policy.c and implement the
ARP-like resolution queue we've all been dreaming of.
The idea would be to queue packets to the policy, then
once the larval state is resolved by the key manager we
re-resolve the route and push the packets out. The
packets would timeout if the rule didn't get resolved
in a certain amount of time.
Signed-off-by: David S. Miller <davem@davemloft.net>
Use menuconfigs instead of menus, so the whole menu can be disabled at
once instead of going through all options.
Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
SPIN_LOCK_UNLOCKED cleanup,use __SPIN_LOCK_UNLOCKED instead
Signed-off-by: Milind Arun Choudhary <milindchoudhary@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This prints the value of the parsed Elapsed Time when received via a
Timestamp Echo option [RFC 4342, 13.3].
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This fixes an error in the calculation of t_ipi when X converges towards
very low sending rates (between 1 and 64 bytes per second).
Although this case may not sound likely, it can be reproduced by connecting,
hitting enter (1 byte sent) and waiting for some time, during which the
nofeedback timer halves the sending rate until finally it reaches the region
1..64 bytes/sec. Computing X is handled correctly (tested separately); but by
dividing X _before_ entering the calculation of t_ipi, X becomes zero as
a result. This in turn triggers a BUG condition caught in scaled_div().
Fixed by replacing with equivalent statement and explicit typecast for good
measure.
Calculation verified and effect of patch tested - reduced never below 1 byte
per 64 seconds afterwards, i.e. not allowing divide-by-zero.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The patch follows the following recommendation made in an erratum to RFC 4342:
"Senders MAY additionally make use of other available RTT measurements,
including those from the initial Request-Response packet exchange."
It implements larger initial windows with regard to this inital RTT measurement,
using the mechanism suggested in draft-ietf-dccp-rfc3448bis, section 4.2.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
