On IPsec hardware offloading, we already get a secpath with
valid state attached when the packet enters the GRO handlers.
So check for hardware offload and skip the state lookup in this
case.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Both esp4 and esp6 used to assume that the SKB payload is encrypted
and therefore the inner_network and inner_transport offsets are
not relevant.
When doing crypto offload in the NIC, this is no longer the case
and the NIC driver needs these offsets so it can do TX TCP checksum
offloading.
This patch sets the inner_network and inner_transport members of
the SKB, as well as encapsulation, to reflect the actual positions
of these headers, and removes them only once encryption is done
on the payload.
Signed-off-by: NIlan Tayari <ilant@mellanox.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

When we do IPsec offloading, we need a fallback for
packets that were targeted to be IPsec offloaded but
rerouted to a device that does not support IPsec offload.
For that we add a function that checks the offloading
features of the sending device and and flags the
requirement of a fallback before it calls the IPsec
output function. The IPsec output function adds the IPsec
trailer and does encryption if needed.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

This patch adds functions that handles IPsec sequence
numbers for GSO segments and TSO offloading. We need
to calculate and update the sequence numbers based
on the segments that GSO/TSO will generate. We need
this to keep software and hardware sequence number
counter in sync.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

This patch extends the xfrm_type by an encap function pointer
and implements esp4_gso_encap and esp6_gso_encap. These functions
doing the basic esp encapsulation for a GSO packet. In case the
GSO packet needs to be segmented in software, we add gso_segment
functions. This codepath is going to be used on esp hardware
offloads.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

This patch adds all the bits that are needed to do
IPsec hardware offload for IPsec states and ESP packets.
We add xfrmdev_ops to the net_device. xfrmdev_ops has
function pointers that are needed to manage the xfrm
states in the hardware and to do a per packet
offloading decision.

Joint work with:
Ilan Tayari <ilant@mellanox.com>
Guy Shapiro <guysh@mellanox.com>
Yossi Kuperman <yossiku@mellanox.com>
Signed-off-by: NGuy Shapiro <guysh@mellanox.com>
Signed-off-by: NIlan Tayari <ilant@mellanox.com>
Signed-off-by: NYossi Kuperman <yossiku@mellanox.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

This is needed for the upcomming IPsec device offloading.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

We add a struct  xfrm_type_offload so that we have the offloaded
codepath separated to the non offloaded codepath. With this the
non offloade and the offloaded codepath can coexist.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

This is an add-on to the previous patch that passes the extended ACK
structure where it's already available by existing genl_info or extack
function arguments.

This was done with this spatch (with some manual adjustment of
indentation):

@@
expression A, B, C, D, E;
identifier fn, info;
@@
fn(..., struct genl_info *info, ...) {
...
-nlmsg_parse(A, B, C, D, E, NULL)
+nlmsg_parse(A, B, C, D, E, info->extack)
...
}

@@
expression A, B, C, D, E;
identifier fn, info;
@@
fn(..., struct genl_info *info, ...) {
<...
-nla_parse_nested(A, B, C, D, NULL)
+nla_parse_nested(A, B, C, D, info->extack)
...>
}

@@
expression A, B, C, D, E;
identifier fn, extack;
@@
fn(..., struct netlink_ext_ack *extack, ...) {
<...
-nlmsg_parse(A, B, C, D, E, NULL)
+nlmsg_parse(A, B, C, D, E, extack)
...>
}

@@
expression A, B, C, D, E;
identifier fn, extack;
@@
fn(..., struct netlink_ext_ack *extack, ...) {
<...
-nla_parse(A, B, C, D, E, NULL)
+nla_parse(A, B, C, D, E, extack)
...>
}

@@
expression A, B, C, D, E;
identifier fn, extack;
@@
fn(..., struct netlink_ext_ack *extack, ...) {
...
-nlmsg_parse(A, B, C, D, E, NULL)
+nlmsg_parse(A, B, C, D, E, extack)
...
}

@@
expression A, B, C, D;
identifier fn, extack;
@@
fn(..., struct netlink_ext_ack *extack, ...) {
<...
-nla_parse_nested(A, B, C, D, NULL)
+nla_parse_nested(A, B, C, D, extack)
...>
}

@@
expression A, B, C, D;
identifier fn, extack;
@@
fn(..., struct netlink_ext_ack *extack, ...) {
<...
-nlmsg_validate(A, B, C, D, NULL)
+nlmsg_validate(A, B, C, D, extack)
...>
}

@@
expression A, B, C, D;
identifier fn, extack;
@@
fn(..., struct netlink_ext_ack *extack, ...) {
<...
-nla_validate(A, B, C, D, NULL)
+nla_validate(A, B, C, D, extack)
...>
}

@@
expression A, B, C;
identifier fn, extack;
@@
fn(..., struct netlink_ext_ack *extack, ...) {
<...
-nla_validate_nested(A, B, C, NULL)
+nla_validate_nested(A, B, C, extack)
...>
}
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Reviewed-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pass the new extended ACK reporting struct to all of the generic
netlink parsing functions. For now, pass NULL in almost all callers
(except for some in the core.)
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add the base infrastructure and UAPI for netlink extended ACK
reporting. All "manual" calls to netlink_ack() pass NULL for now and
thus don't get extended ACK reporting.

Big thanks goes to Pablo Neira Ayuso for not only bringing up the
whole topic at netconf (again) but also coming up with the nlattr
passing trick and various other ideas.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Reviewed-by: NDavid Ahern <dsa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Kees Cook has pointed out that xfrm_replay_state_esn_len() is subject to
wrapping issues.  To ensure we are correctly ensuring that the two ESN
structures are the same size compare both the overall size as reported
by xfrm_replay_state_esn_len() and the internal length are the same.

CVE-2017-7184
Signed-off-by: NAndy Whitcroft <apw@canonical.com>
Acked-by: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When a new xfrm state is created during an XFRM_MSG_NEWSA call we
validate the user supplied replay_esn to ensure that the size is valid
and to ensure that the replay_window size is within the allocated
buffer.  However later it is possible to update this replay_esn via a
XFRM_MSG_NEWAE call.  There we again validate the size of the supplied
buffer matches the existing state and if so inject the contents.  We do
not at this point check that the replay_window is within the allocated
memory.  This leads to out-of-bounds reads and writes triggered by
netlink packets.  This leads to memory corruption and the potential for
priviledge escalation.

We already attempt to validate the incoming replay information in
xfrm_new_ae() via xfrm_replay_verify_len().  This confirms that the user
is not trying to change the size of the replay state buffer which
includes the replay_esn.  It however does not check the replay_window
remains within that buffer.  Add validation of the contained
replay_window.

CVE-2017-7184
Signed-off-by: NAndy Whitcroft <apw@canonical.com>
Acked-by: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

x86_64 is zero-extending arch so "unsigned int" is preferred over "int"
for address calculations.

Space savings:

	add/remove: 0/0 grow/shrink: 0/3 up/down: 0/-58 (-58)
	function                                     old     new   delta
	xfrm_hash_resize                            2752    2743      -9
	policy_hash_bysel                            985     973     -12
	policy_hash_direct                          1036     999     -37
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Fix xfrm_neigh_lookup to provide dst->path to the
neigh_lookup dst_ops method.

When skb is provided, the IP address in packet should already
match the dst->path address family. But for the non-skb case,
we should consider the last tunnel address as nexthop address.

Fixes: f894cbf8 ("net: Add optional SKB arg to dst_ops->neigh_lookup().")
Signed-off-by: NJulian Anastasov <ja@ssi.bg>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds GRO ifrastructure and callbacks for ESP on
ipv4 and ipv6.

In case the GRO layer detects an ESP packet, the
esp{4,6}_gro_receive() function does a xfrm state lookup
and calls the xfrm input layer if it finds a matching state.
The packet will be decapsulated and reinjected it into layer 2.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

We need to keep per packet offloading informations across
the layers. So we extend the sec_path to carry these for
the input and output offload codepath.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

We need it in the ESP offload handlers, so export it.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

The upcomming IPsec ESP gro callbacks will consume the skb,
so prepare for that.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Add a new helper to set the secpath to the skb.
This avoids code duplication, as this is used
in multiple places.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

On IPv4-mapped IPv6 addresses sk_family is AF_INET6,
but the flow informations are created based on AF_INET.
So the routing set up 'struct flowi4' but we try to
access 'struct flowi6' what leads to an out of bounds
access. Fix this by using the family we get with the
dst_entry, like we do it for the standard policy lookup.
Reported-by: NDmitry Vyukov <dvyukov@google.com>
Tested-by: NDmitry Vyukov <dvyukov@google.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Alternative is to keep it an make the (unused) afinfo arg const to avoid
the compiler warnings once the afinfo structs get constified.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Only needed it to register the policy backend at init time.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Just call xfrm_garbage_collect_deferred() directly.
This gets rid of a write to afinfo in register/unregister and allows to
constify afinfo later on.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Nothing checks the return value. Also, the errors returned on unregister
are impossible (we only support INET and INET6, so no way
xfrm_policy_afinfo[afinfo->family] can be anything other than 'afinfo'
itself).
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

The comment makes it look like get_tos() is used to validate something,
but it turns out the comment was about xfrm_find_bundle() which got removed
years ago.

xfrm_get_tos will return either the tos (ipv4) or 0 (ipv6).
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Nothing writes to these structures (the module owner was not used).

While at it, size xfrm_input_afinfo[] by the highest existing xfrm family
(INET6), not AF_MAX.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Dmitry reports following splat:
 INFO: trying to register non-static key.
 the code is fine but needs lockdep annotation.
 turning off the locking correctness validator.
 CPU: 0 PID: 13059 Comm: syz-executor1 Not tainted 4.10.0-rc7-next-20170207 #1
[..]
 spin_lock_bh include/linux/spinlock.h:304 [inline]
 xfrm_policy_flush+0x32/0x470 net/xfrm/xfrm_policy.c:963
 xfrm_policy_fini+0xbf/0x560 net/xfrm/xfrm_policy.c:3041
 xfrm_net_init+0x79f/0x9e0 net/xfrm/xfrm_policy.c:3091
 ops_init+0x10a/0x530 net/core/net_namespace.c:115
 setup_net+0x2ed/0x690 net/core/net_namespace.c:291
 copy_net_ns+0x26c/0x530 net/core/net_namespace.c:396
 create_new_namespaces+0x409/0x860 kernel/nsproxy.c:106
 unshare_nsproxy_namespaces+0xae/0x1e0 kernel/nsproxy.c:205
 SYSC_unshare kernel/fork.c:2281 [inline]

Problem is that when we get error during xfrm_net_init we will call
xfrm_policy_fini which will acquire xfrm_policy_lock before it was
initialized.  Just move it around so locks get set up first.
Reported-by: NDmitry Vyukov <dvyukov@google.com>
Fixes: 283bc9f3 ("xfrm: Namespacify xfrm state/policy locks")
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

We have many gro cells users, so lets move the code to avoid
duplication.

This creates a CONFIG_GRO_CELLS option.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add confirm_neigh method to dst_ops and use it from IPv4 and IPv6
to lookup and confirm the neighbour. Its usage via the new helper
dst_confirm_neigh() should be restricted to MSG_PROBE users for
performance reasons.

For XFRM prefer the last tunnel address, if present. With help
from Steffen Klassert.
Signed-off-by: NJulian Anastasov <ja@ssi.bg>
Acked-by: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds a dummy network device so that we can
use gro_cells for IPsec GRO. With this, we handle IPsec
GRO with no impact on the generic networking code.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Dan reports following smatch warning:
 net/xfrm/xfrm_state.c:659
 error: we previously assumed 'afinfo' could be null (see line 651)

 649  struct xfrm_state_afinfo *afinfo = xfrm_state_afinfo_get_rcu(family);
 651  if (afinfo)
		...
 658  }
 659  afinfo->init_temprop(x, tmpl, daddr, saddr);

I am resonably sure afinfo cannot be NULL here.

xfrm_state4.c and state6.c are both part of ipv4/ipv6 (depends on
CONFIG_XFRM, a boolean) but even if ipv6 is a module state6.c can't
be removed (ipv6 lacks module_exit so it cannot be removed).

The only callers for xfrm6_fini that leads to state backend unregister
are error unwinding paths that can be called during ipv6 init function.

So after ipv6 module is loaded successfully the state backend cannot go
away anymore.

The family value from policy lookup path is taken from dst_entry, so
that should always be AF_INET(6).

However, since this silences the warning and avoids readers of this
code wondering about possible null deref it seems preferrable to
be defensive and just add the old check back.

Fixes: 711059b9 ("xfrm: add and use xfrm_state_afinfo_get_rcu")
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Instead of:
  if (foo) {
      unlock();
      return bar();
   }
   unlock();
do:
   unlock();
   if (foo)
       return bar();

This is ok because rcu protected structure is only dereferenced before
the conditional.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

xfrm_init_tempstate is always called from within rcu read side section.
We can thus use a simpler function that doesn't call rcu_read_lock
again.

While at it, also make xfrm_init_tempstate return value void, the
return value was never tested.

A followup patch will replace remaining callers of xfrm_state_get_afinfo
with xfrm_state_afinfo_get_rcu variant and then remove the 'old'
get_afinfo interface.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

commit 44abdc30
("xfrm: replace rwlock on xfrm_state_afinfo with rcu") made
xfrm_state_put_afinfo equivalent to rcu_read_unlock.

Use spatch to replace it with direct calls to rcu_read_unlock:

@@
struct xfrm_state_afinfo *a;
@@

-  xfrm_state_put_afinfo(a);
+  rcu_read_unlock();

old:
 text    data     bss     dec     hex filename
22570      72     424   23066    5a1a xfrm_state.o
 1612       0       0    1612     64c xfrm_output.o
new:
22554      72     424   23050    5a0a xfrm_state.o
 1596       0       0    1596     63c xfrm_output.o
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

xfrm/xfrm_state.c:1973:21: error: incompatible types in comparison expression (different address spaces)

Harmless, but lets fix it to reduce the noise.

While at it, get rid of unneeded NULL check, its never hit:

net/ipv4/xfrm4_state.c: xfrm_state_register_afinfo(&xfrm4_state_afinfo);
net/ipv6/xfrm6_state.c: return xfrm_state_register_afinfo(&xfrm6_state_afinfo);
net/ipv6/xfrm6_state.c: xfrm_state_unregister_afinfo(&xfrm6_state_afinfo);

... are the only callsites.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Once flow cache gets removed the mtu initialisation happens for every skb
that gets an xfrm attached, so this lock starts to show up in perf.

It is not obvious why this lock is required -- the caller holds
reference on the state struct, type->destructor is only called from the
state gc worker (all state structs on gc list must have refcount 0).

xfrm_init_state already has been called (else private data accessed
by type->get_mtu() would not be set up).

So just remove the lock -- the race on the state (DEAD?) doesn't
matter (could change right after dropping the lock too).
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

o s/descentant/descendant
o s/workarbound/workaround
Signed-off-by: NAlexander Alemayhu <alexander@alemayhu.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>