My IPsec MTU optimization patch introduced a regression in MTU calculation
for non-ESP SAs, the SA's header_len needs to be subtracted from the MTU if
the transform doesn't provide a ->get_mtu() function.

Reported-and-tested-by: Marco Berizzi <pupilla@hotmail.com>

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently we check for permission before deleting entries from SAD and
SPD, (see security_xfrm_policy_delete() security_xfrm_state_delete())
However we are not checking for authorization when flushing the SPD and
the SAD completely. It was perhaps missed in the original security hooks
patch.

This patch adds a security check when flushing entries from the SAD and
SPD.  It runs the entire database and checks each entry for a denial.
If the process attempting the flush is unable to remove all of the
entries a denial is logged the the flush function returns an error
without removing anything.

This is particularly useful when a process may need to create or delete
its own xfrm entries used for things like labeled networking but that
same process should not be able to delete other entries or flush the
entire database.

Signed-off-by: Joy Latten<latten@austin.ibm.com>
Signed-off-by: Eric Paris <eparis@parisplace.org>
Signed-off-by: James Morris <jmorris@namei.org>

Signed-off-by: David S. Miller <davem@davemloft.net>

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>

This patch adds some casts to shut up the warnings introduced by my
last patch that added a common interator function for xfrm algorightms.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

This is a natural extension of the changeset

    [XFRM]: Probe selected algorithm only.

which only removed the probe call for xfrm_user.  This patch does exactly
the same thing for af_key.  In other words, we load the algorithm requested
by the user rather than everything when adding xfrm states in af_key.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

Multi-page allocations are always likely to fail.  Since such failures
are expected and non-critical in xfrm_hash_alloc, we shouldn't warn about
them.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

The function xfrm_policy_byid takes a dir argument but finds the policy
using the index instead.  We only use the dir argument to update the
policy count for that direction.  Since the user can supply any value
for dir, this can corrupt our policy count.

I know this is the problem because a few days ago I was deleting
policies by hand using indicies and accidentally typed in the wrong
direction.  It still deleted the policy and at the time I thought
that was cool.  In retrospect it isn't such a good idea :)

I decided against letting it delete the policy anyway just in case
we ever remove the connection between indicies and direction.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

Aggregate the SPD info TLVs.

Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>