add support functions for attributes and callback handlers
added support functions to access the netlink attributes and use
custom callback handlers. Most is wrapped as is, but there are
a couple of special cases handled.
1) void *nla_data(struct nlattr *);
The return value is changed to a Python byte array so it includes
the lenght of the data stream.
2) int nla_parse_nested(...);
This returns a tuple (err, dict). 'err' is the error code and 'dict'
is a dictionary with attribute identifier as key and value represents
a struct nlattr object.
3) macro nla_for_each_nested()
Provide nla_get_nested() which returns a Python list of struct nlattr
objects that is iterable.
4) allocate struct nla_policy array
Provide nla_policy_array() function that allocates consecutive space
in memory for struct nla_policy array entries. Each entry is put in
a Python list so the entry fields can be modified in Python. This
array object can be passed to the nla_parse_nested() function.
Signed-off-by: Arend van Spriel <arend@broadcom.com> Signed-off-by: Thomas Graf <tgraf@suug.ch>
Thomas Graf [Thu, 27 Jun 2013 16:29:17 +0000 (18:29 +0200)]
msg: Avoid returning a negative value for nlmsg_attrlen()
If a hdrlen was provided that was greather than the actual
message length, a negative attributes length would result.
This was typically happening for RTM_GETLINK requests where
we can get a away with a 4 bytes header on the request side
but the response would use a 16 bytes header.
This resulted in strange -8 bytes leftover debug messages.
Andrew Collins [Mon, 17 Jun 2013 21:58:43 +0000 (15:58 -0600)]
Handle -NLE_AGAIN in nl_cache_mngr_data_ready
Since commit "nl: Return -NLE_AGAIN if non-blocking socket would block",
nl_cache_mngr_data_ready returns -NLE_AGAIN to callers on non-blocking sockets.
Change it to consider -NLE_AGAIN as a non-error case as it is expected behavior
with the nl_recv changes.
Andrew Collins [Mon, 17 Jun 2013 21:24:05 +0000 (15:24 -0600)]
Default to comparing all attributes if no oo_id_attrs defined
Since commit: "cache pickup: Avoid duplicates during cache pickup",
nfnl_ct_alloc_cache no longer properly fills the cache, as it doesn't
define oo_id_attrs so all items are considered duplicates.
Instead of adding a ~0 oo_id_attrs to ct_obj, this changes
nl_object_identical to default to comparing all attributes if
neither oo_id_attrs_get or oo_id_attrs are provided.
Thomas Graf [Wed, 8 May 2013 11:52:27 +0000 (13:52 +0200)]
nl: Increase receive buffer size to 4 pages
Assuming that the kernel does not send more than a page is no longer valid,
and enabling MSG_PEEK'ing by default to figure out the exact message buffer
requirements can have a negative influence on the performance of existing
applications. Bumping the default receive buffer space to 4 pages seems
a sane default.
rtnl_link_af_unregister() attempts to write-lock info_lock twice
instead of releasing it before returning. It also will return with
info_lock write-locked if passed a NULL ops.
There seams to be an error in the calculation of needed space for the message in nla_reserve. The current size of the message is counted twice: Once in NLMSG_ALIGN, once in the condition below.
This causes nla_put_* calls to be rejected if the allocation size of the message has been strictly calculated by the caller.
Fix leak of cb if nl_socket_alloc_cb() failed to allocate socket
- each *_get() should have corresponding *_put(). That rule was broken in nl_socket_alloc()
- Also, check if cb is NULL in nl_socket_set_cb (calls BUG())
Passing a NULL pointer would cause a NULL pointer dereference within
nl_object_free().
Returning early on NULL pointer is the behavior free(3) and other
nl*_free() functions.
Thomas Graf [Tue, 2 Apr 2013 09:58:18 +0000 (11:58 +0200)]
nl: Return -NLE_AGAIN if non-blocking socket would block
Previously 0 was returned which gave the caller no chance of detecting
when a non-blocking socket would block. If a caller intends to never
see an error message it should utilize poll()/select() to only read
when the socket has pending data or information.
Reported-by: Holger Eitzenberger <holger@eitzenberger.org> Signed-off-by: Thomas Graf <tgraf@suug.ch>
Add ICMPv6 type, code and ID (if set) by using the already available
conntrack atttributes.
Currently the ICMPv6 conntrack objects in libnl are without type, code
and ID. This e. g. is the output of nl_object_dump() without the patch:
ipv6-icmp ::1 <-> ::1
id 0xdd0871f0 family inet6 timeout 30s <NOREPLY,SNAT_INIT,DNAT_INIT>
The attached patch tries to solve that. It then looks like
ipv6-icmp ::1 <-> ::1 icmp type 128 code 0 id 28253
id 0xdf3a11f0 family inet6 timeout 30s <SNAT_INIT,DNAT_INIT>
It is the 'small' approach, because it reuses the existing ICMP
attributes of the conntrack object (currently only used for IPv4).
This way I can avoid to add new _icmp6_get_, _icmp6_set_ and
_icmp6_test_ functions.
Signed-off-by: Holger Eitzenberger <holger@eitzenberger.org> Signed-off-by: Thomas Graf <tgraf@suug.ch>
Thomas Graf [Mon, 1 Apr 2013 09:16:34 +0000 (11:16 +0200)]
genl: Update mt_id of cache ops when resolving genl id
The cache layer uses the message type array stored in the cache
ops to lookup which cache a message belongs to. Update to the
the message array with the resolved generic netlink id to make
it compatible with the caching API.
Allows to use nl_cache_refill() and others for generic netlink
based caches with dynamic generic netlink ids.
Thomas Graf [Thu, 14 Mar 2013 17:52:17 +0000 (18:52 +0100)]
rtnl-addr: Inherit prefix length to nl_addr objs in rtnl_addr_set_prefixlen()
Previously if using rtnl_addr_set_prefixlen() the new prefix length
was not forwarded to the corresponding 'struct nl_addr' objects
associated with address already and thus the comparison function
would fail.
This patch also clears the internal ADDR_ATTR_PREFIXLEN flag if
the prefix length has been reset.
Thomas Graf [Thu, 14 Mar 2013 15:25:17 +0000 (16:25 +0100)]
tests: Add check based unit test system
Introduces new unit tests based on `check`. Each subsystem/module can
have its own unit tests in tests/check-<name>.c that will be linked
together in tests/check-all.c.
Running 'make check' will compile and run the unit tests automatically.
A reference unit test implementation has been done for the abstract
address module.
Thomas Graf [Wed, 13 Mar 2013 16:12:03 +0000 (17:12 +0100)]
attr: Warn application if nla_parse() observes same attribute multiple times
Use a debugging message to warn applications if an attribute is
found multiple times in the same message. It is perfectly valid
to rely on this behaviour but it is likely to indicate a bug.
roopa [Fri, 15 Feb 2013 18:26:30 +0000 (10:26 -0800)]
link: Fix rtnl_link_af_data_compare return value
This patch fixes a bug where because of the af_ops check
being first in the function, we were returning ~0 if af_ops
was null even if both objects really did not have af_data
and we should be returning 0.
Its better to have the af_data present check before anything else.
So, Rearranged some of the code in rtnl_link_af_data_compare.
Changes include:
- Do the attribute present check before anything else
- If ao_compare op not present, return ~0
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Reviewed-by: Nolan Leake <nolan@cumulusnetworks.com> Reviewed-by: Shrijeet Mukherjee <shm@cumulusnetworks.com> Reviewed-by: Wilson Kok <wkok@cumulusnetworks.com> Signed-off-by: Thomas Graf <tgraf@suug.ch>
Thomas Graf [Tue, 5 Feb 2013 21:41:26 +0000 (22:41 +0100)]
bridge: Support the new bridging attributes
This provides support for the new bridging attributes provided
in IFLA_PROTINFO while maintaining backwards compatibility
with older kernels.
A set of new API functions are exported to access the bridging
information. rtnl_link_bridge_has_ext_info() can be used to
check whether a bridge object has been constructed based on
the newly available attributes or the old message format.
Thomas Graf [Fri, 1 Feb 2013 09:41:45 +0000 (10:41 +0100)]
neigh: Remove check for AF_UNSPEC in rtnl_neigh_get()
This check was introduces to not accidently return AF_BRIDGE objects
to unaware API users as they do differ in structure. However, such
objects are only available if explicitely requests using the
NL_CACHE_AF_ITER flag or by using arg1 == AF_BRIDGE for the cache.
Therefore remove this check and allow rtnl_neigh_get() to be used to
fetch any neighbor object of a cache.
Reported-by: Maxime Bizon <mbizon@freebox.fr> Signed-off-by: Thomas Graf <tgraf@suug.ch>
roopa [Mon, 28 Jan 2013 15:46:16 +0000 (07:46 -0800)]
link cache: remove AF_UNSPEC check in rtnl_get_link and rtnl_get_link_by_name
This patch reverts back the AF_UNSPEC check introduced by AF_BRIDGE
changes at http://lists.infradead.org/pipermail/libnl/2012-November/000796.html
After the addition of AF_BRIDGE support, link cache can now contain objects of
type AF_BRIDGE. To make sure existing api's did not return AF_BRIDGE objects
and surprise existing callers, I introduced the check for AF_UNSPEC.
But from what Andy Wang reported, rtnl_link_get_by_name returns the first
link object with matching ifindex and that could have not only been AF_UNSPEC
but also of family AF_INET6. And his app always got an AF_INET6 object prior
to the patch that introduced the AF_UNSPEC check.
I could just add AF_INET6 family check along with AF_UNSPEC in the apis and that
should work well.
But thinking about it some more, removing the AF_UNSPEC change seems to be safer at
this point. That way this api will retain its semantics and return the first object
with matching ifindex. It could be of any supported family. The user will know if the
cache contains bridge objects, because they are available only with the cache flag
NL_CACHE_AF_ITER. Besides, if new users want to search for a specific object,
nl_cache_find is a better option.
Reported-by: Andy Wang <Andy.Wang@watchguard.com> Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Signed-off-by: Thomas Graf <tgraf@suug.ch>
This commit causes a regression so no app using libnl can be compiled
against it. This patch fixes it by removing includes of no-longe
existing headers.
Signed-off-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: Thomas Graf <tgraf@suug.ch>
roopa [Thu, 17 Jan 2013 14:48:59 +0000 (06:48 -0800)]
route cache: This patch adds route priority to route object oo_id_attrs
The kernel allows multiple entries in the main table which differ in the
priority value. In libnl currently, since priority is not part of the base
netlink route message, it is not used as part of the key. This patch
includes priority in the key/oo_id_attrs and defaults the value to zero
for messages where priority is not included.
One point to note is that the actual selection of route from multiple
options is done implicitly in the kernel by storing the routes in sort
priority order, but there is no explicit communication to a client of libnl
of that.
Thomas Graf [Tue, 22 Jan 2013 18:10:38 +0000 (19:10 +0100)]
No longer install module API headers
Various header files providing an API to implement own cache and
object types or implement link types have been available in the
past. Their API is marked unstable in the documentation and nobody
is using them so far.
Technically they have been causing ABI breakages in at least two
3.2.x releases. In order to avoid future accidental breakage, no
longer install these and require module developers to clone the
git tree and build modules off the git tree directly to make sure
that the API is unstable at this point.
Thomas Graf [Tue, 22 Jan 2013 18:07:09 +0000 (19:07 +0100)]
Undo soname bump
The soname was bumped before 3.2.18 was released to reflect
an ABI change in the cache and object API.
This caused a discussion with various distribution maintainers
involved as it prevented them from including the release in
their stable branches. This is especially unfortunate as the
corresponding API is unused outside of libnl as of now.
For this reason, I have decided to undo the soname bump and
instead remove the corresponding header files from the list of
installable headers and thus remove them from the public API.
This is a API break technically but since nobody is using
them it should not matter. If you are in fact using any of the
*-api.h headers please let me know and we are most likely to
start a new development branch.
If your application linked against 3.2.18 or 3.2.19 you will need
to relink if you want it to use >= 3.2.20.
roopa [Fri, 18 Jan 2013 00:29:04 +0000 (16:29 -0800)]
link: Add af data compare to link objects
Today the link compare function does not
compare af data of a link. We have found a
need for this to get approriate change callbacks
when af_data of a link changes.
This patch adds support to compare af_data
to link_compare function. This patch today
only adds support to compare af_data set by
PROTINFO attributes. It can be extended to
support compares of af_data set by AF_SPEC
attributes
It has been tested for AF_BRIDGE objects.
In case of AF_BRIDGE objects, this helps with
bridge port change notification callbacks.
Signed-off-by: Wilson Kok <wkok@cumulusnetworks.com> Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Signed-off-by: Thomas Graf <tgraf@suug.ch>
roopa [Tue, 8 Jan 2013 13:29:08 +0000 (05:29 -0800)]
link af ops: Add new ao_compare op to compare link af_data
This patch adds new operation to compare link af_data.
ao_compare is similar to object oo_compare operation.
This op can be used when two links are compared
for their af data. It takes two link objects in
question, an object specific bitmask defining which
attributes should be compared and flags to control
the behaviour. The function must return a bitmask
with the relevant bit set for each attribute that mismatches.
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Signed-off-by: Thomas Graf <tgraf@suug.ch>
projects / libnl / log