Commit Graph

64 Commits

Author SHA1 Message Date
Jiri Benc
67b61f6c13 netlink: implement nla_get_in_addr and nla_get_in6_addr
Those are counterparts to nla_put_in_addr and nla_put_in6_addr.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-31 13:58:35 -04:00
Jiri Benc
930345ea63 netlink: implement nla_put_in_addr and nla_put_in6_addr
IP addresses are often stored in netlink attributes. Add generic functions
to do that.

For nla_put_in_addr, it would be nicer to pass struct in_addr but this is
not used universally throughout the kernel, in way too many places __be32 is
used to store IPv4 address.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-31 13:58:35 -04:00
Johannes Berg
053c095a82 netlink: make nlmsg_end() and genlmsg_end() void
Contrary to common expectations for an "int" return, these functions
return only a positive value -- if used correctly they cannot even
return 0 because the message header will necessarily be in the skb.

This makes the very common pattern of

  if (genlmsg_end(...) < 0) { ... }

be a whole bunch of dead code. Many places also simply do

  return nlmsg_end(...);

and the caller is expected to deal with it.

This also commonly (at least for me) causes errors, because it is very
common to write

  if (my_function(...))
    /* error condition */

and if my_function() does "return nlmsg_end()" this is of course wrong.

Additionally, there's not a single place in the kernel that actually
needs the message length returned, and if anyone needs it later then
it'll be very easy to just use skb->len there.

Remove this, and make the functions void. This removes a bunch of dead
code as described above. The patch adds lines because I did

-	return nlmsg_end(...);
+	nlmsg_end(...);
+	return 0;

I could have preserved all the function's return values by returning
skb->len, but instead I've audited all the places calling the affected
functions and found that none cared. A few places actually compared
the return value with <= 0 in dump functionality, but that could just
be changed to < 0 with no change in behaviour, so I opted for the more
efficient version.

One instance of the error I've made numerous times now is also present
in net/phonet/pn_netlink.c in the route_dumpit() function - it didn't
check for <0 or <=0 and thus broke out of the loop every single time.
I've preserved this since it will (I think) have caused the messages to
userspace to be formatted differently with just a single message for
every SKB returned to userspace. It's possible that this isn't needed
for the tools that actually use this, but I don't even know what they
are so couldn't test that changing this behaviour would be acceptable.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-18 01:03:45 -05:00
Thomas Graf
149118d893 netlink: Warn on unordered or illegal nla_nest_cancel() or nlmsg_cancel()
Calling nla_nest_cancel() in a different order as the nesting was
built up can lead to negative offsets being calculated which
results in skb_trim() being called with an underflowed unsigned
int. Warn if mark < skb->data as it's definitely a bug.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-05 22:38:22 -05:00
Simon Horman
941d8ebcf7 datapath: Rename last_action() as nla_is_last() and move to netlink.h
The original motivation for this change was to allow the helper to be used
in files other than actions.c as part of work on an odp select group
action.

It was as pointed out by Thomas Graf that this helper would be best off
living in netlink.h. Furthermore, I think that the generic nature of this
helper means it is best off in netlink.h regardless of if it is used more
than one .c file or not. Thus, I would like it considered independent of
the work on an odp select group action.

Cc: Thomas Graf <tgraf@suug.ch>
Cc: Pravin Shelar <pshelar@nicira.com>
Cc: Andy Zhou <azhou@nicira.com>
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Acked-by: Thomas Graf <tgraf@noironetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-28 17:07:29 -04:00
Nicolas Dichtel
2c6ba4b15b netlink: fix description of portid
Avoid confusion between pid and portid.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-16 14:52:35 -04:00
Mark Rustad
d87de1f3e9 netlink: Fix shadow warning on jiffies
Change formal parameter name to not shadow the global jiffies.

Signed-off-by: Mark Rustad <mark.d.rustad@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-28 17:20:43 -07:00
Joe Perches
4f69053b72 netevent/netlink.h: Remove extern from function prototypes
There are a mix of function prototypes with and without extern
in the kernel sources.  Standardize on not using extern for
function prototypes.

Function prototypes don't need to be written with extern.
extern is assumed by the compiler.  Its use is as unnecessary as
using auto to declare automatic/local variables in a block.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-21 14:01:39 -04:00
Eric W. Biederman
15e473046c netlink: Rename pid to portid to avoid confusion
It is a frequent mistake to confuse the netlink port identifier with a
process identifier.  Try to reduce this confusion by renaming fields
that hold port identifiers portid instead of pid.

I have carefully avoided changing the structures exported to
userspace to avoid changing the userspace API.

I have successfully built an allyesconfig kernel with this change.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-10 15:30:41 -04:00
Jiri Pirko
4778e0be16 netlink: add signed types
Signed types might be needed in NL communication from time to time
(I need s32 in team driver), so add them.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-03 20:40:11 -07:00
David S. Miller
b3fe91c53a netlink: Delete all NLA_PUT*() macros.
They were error prone due to an embedded goto, and the entire tree has
been converted away from using them.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-02 04:33:45 -04:00
David S. Miller
24c410dce3 netlink: Add nla_put_le{16,32,64}() helpers.
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-02 04:33:42 -04:00
David S. Miller
6c1dd3b6a3 netlink: Add nla_put_net{16,32,64}() helpers.
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-02 04:33:41 -04:00
David S. Miller
569a8fc383 netlink: Add nla_put_be{16,32,64}() helpers.
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-01 18:11:37 -04:00
Denys Vlasenko
a46621a3a8 net: Deinline __nlmsg_put and genlmsg_put. -7k code on i386 defconfig.
text	   data	    bss	    dec	    hex	filename
8455963	 532732	1810804	10799499 a4c98b	vmlinux.o.before
8448899	 532732	1810804	10792435 a4adf3	vmlinux.o

This change also removes commented-out copy of __nlmsg_put
which was last touched in 2005 with "Enable once all users
have been converted" comment on top.

Changes in v2: rediffed against net-next.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-30 15:22:06 -05:00
Johannes Berg
4b6cc7284d netlink: clarify attribute length check documentation
The documentation for how the length of attributes
is checked is wrong ("Exact length" isn't true, the
policy checks are for "minimum length") and a bit
misleading. Make it more complete and explain what
really happens.

Cc: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-04 17:48:23 -04:00
Johannes Berg
670dc2833d netlink: advertise incomplete dumps
Consider the following situation:
 * a dump that would show 8 entries, four in the first
   round, and four in the second
 * between the first and second rounds, 6 entries are
   removed
 * now the second round will not show any entry, and
   even if there is a sequence/generation counter the
   application will not know

To solve this problem, add a new flag NLM_F_DUMP_INTR
to the netlink header that indicates the dump wasn't
consistent, this flag can also be set on the MSG_DONE
message that terminates the dump, and as such above
situation can be detected.

To achieve this, add a sequence counter to the netlink
callback struct. Of course, netlink code still needs
to use this new functionality. The correct way to do
that is to always set cb->seq when a dumpit callback
is invoked and call nl_dump_check_consistent() for
each new message. The core code will also call this
function for the final MSG_DONE message.

To make it usable with generic netlink, a new function
genlmsg_nlhdr() is needed to obtain the netlink header
from the genetlink user header.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-06-22 16:09:45 -04:00
Justin P. Mattock
70f23fd66b treewide: fix a few typos in comments
- kenrel -> kernel
- whetehr -> whether
- ttt -> tt
- sss -> ss

Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-05-10 10:16:21 +02:00
Jozsef Kadlecsik
f703651ef8 netfilter: NFNL_SUBSYS_IPSET id and NLA_PUT_NET* macros
The patch adds the NFNL_SUBSYS_IPSET id and NLA_PUT_NET* macros to the
vanilla kernel.

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2011-02-01 15:20:14 +01:00
Jan Engelhardt
3654654f7a netlink: let nlmsg and nla functions take pointer-to-const args
The changed functions do not modify the NL messages and/or attributes
at all. They should use const (similar to strchr), so that callers
which have a const nlmsg/nlattr around can make use of them without
casting.

While at it, constify a data array.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-16 09:52:32 -08:00
Nelson Elhage
6b8c92ba07 netlink: Make nlmsg_find_attr take a const nlmsghdr*.
This will let us use it on a nlmsghdr stored inside a netlink_callback.

Signed-off-by: Nelson Elhage <nelhage@ksplice.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-04 12:26:34 -07:00
Justin P. Mattock
1dc8d8c06d net: Fix a typo in netlink.h
Fix a typo in include/net/netlink.h
should be finalize instead of finanlize

Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-23 12:58:40 -07:00
Pablo Neira Ayuso
f5d410f2ea netlink: fix unaligned access in nla_get_be64()
This patch fixes a unaligned access in nla_get_be64() that was
introduced by myself in a17c859849.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-19 22:47:23 -07:00
Alexey Dobriyan
b54452b07a const: struct nla_policy
Make remaining netlink policies as const.
Fixup coding style where needed.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-02-18 14:30:18 -08:00
Patrick McHardy
3a6c2b419b netlink: constify nlmsghdr arguments
Consitfy nlmsghdr arguments to a couple of functions as preparation
for the next patch, which will constify the netlink message data in
all nfnetlink users.

Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-08-25 16:07:40 +02:00