Consider:
unshare -n
ip link add d0 type dummy
ip link add d1 type dummy
ip link set d0 up
ip link set d1 up
ip addr add 192.168.100.5/24 dev d0
ip addr add 192.168.101.5/24 dev d1
ip route add 192.168.200.0/24 via 192.168.100.1
ip monitor &
ip route change 192.168.200.0/24 via 192.168.101.1
#prints 192.168.200.0/24 via 192.168.101.1 dev d1
ip route show
#192.168.100.0/24 dev d0 proto kernel scope link src 192.168.100.5
#192.168.101.0/24 dev d1 proto kernel scope link src 192.168.101.5
#192.168.200.0/24 via 192.168.101.1 dev d1
Note that `ip route change` replaced the exising route. "Replaced" in this
case means: the previous route on device "d0" got removed and a new route
on "d1" was added. However, kernel only sent one RTM_NEWROUTE event, no
RTM_DELROUTE that notifies about this change.
We need to workaround that by re-synching the routes when we receive a
RTM_NEWROUTE notification.
NMPCacheId is a union with fields for all known NMPCacheIdTypes.
Up to now, we always cloned the entire union, computed the hash
over all (possibly unset) fields and used memcmp() unanimously.
That was ok, because NMPCacheId was 16 bytes in total and cache-id
types that consumed less bytes didn't have a large overhead.
Next, we will add a new cache id type which increases the size of
NMPCacheId to 24 bytes. So, while possibly only a fraction of the
instances is that large, they would all have to pay that price.
Change that to consider and clone only those parts of the id
that are actually used.
As we get more NMPCacheIdType values, it's better to have for
each type a pre-declared list of supported types, instead of
iterating over all types and letting _nmp_object_init_cache_id()
figure out that the cache-id-type is unsupported on that object.
Inside container, where we don't use udev we don't receive
any events from udev client. Thus the client only returns
devices when iterating it initially, but no events for newly
added devices that appear later.
Thus, inside containers we don't want to create a udev client
at all.
- "gsystem-local-alloc.h" and <gio/gio.h> are already included via
"nm-default.h". No need to include them separately.
- include "nm-macros-internal.h" via "nm-default.h" and drop all
explict includes.
- in the modified files, ensure that we always include "config.h"
and "nm-default.h" first. As second, include the header file
for the current source file (if applicable). Then follow external
includes and finally internal nm includes.
- include nm headers inside source code files with quotes
- internal header files don't need to include default headers.
They can savely assume that "nm-default.h" is already included
and with it glib, nm-glib.h, nm-macros-internal.h, etc.
Downsides:
- Add some additional overhead to manage the index
- The NMPCacheId struct grows to 16 bytes, affecting
hashing performance for all object types.
Still do it, based on the assumption that it doesn't matter
for a low number of interfaces. But the O(1) access time matters
when having lots of interfaces.
We potentially emit a lot of signals. Don't look up the
signal by name because that adds quite some additional
overhead, like peeking for a GQuark.
Instead pass the numeric signal-id directly.
Previously, we could only set the ingress-qos-mappings/egress-qos-mappings.
Now also cache the mappings and expose them from the platform cache.
Also, support changing the vlan flags not only when creating the vlan
interface.
Instead of using libnl-route-3 library to serialize netlink messages,
construct the netlink messages ourselves.
This has several advantages:
- Creating the netlink message ourself is actually more straight
forward then having an intermediate layer between NM and the kernel.
Now it is immediately clear, how a platform request translates to
a netlink/kernel request.
You can look at the kernel sources how a certain netlink attribute
behaves, and then it's immediately clear how to set that (and vice
versa).
- Older libnl versions might have bugs or missing features for which
we needed to workaround (often by offering a reduced/broken/untested
functionality). Now we can get rid or workaround like _nl_has_capability(),
check_support_libnl_extended_ifa_flags(), HAVE_LIBNL_INET6_TOKEN.
Another example is a libnl bug when setting vlan ingress map which
isn't even yet fixed in libnl upstream.
- We no longer need libnl-route-3 at all and can drop that runtime
requirement, saving some 400k.
Constructing the messages ourselves also gives better performance
because we don't have to create the intermediate libnl object.
- In the future we will add more link-type support which is easier
to support by basing directly on the plain kernel/netlink API,
instead of requiring also libnl3 to expose this functionality.
E.g. adding macvtap support: we already parsed macvtap properties
ourselves because of missing libnl support. To *add* macvtap
support, we also would have to do it ourself (or extend libnl).
Constructing the libnl3 object only to parse the message
is wasteful. It involves several memory allocations, thread
synchronization and parsing fields that we don't care about.
But moreover, older libnl version might not support all the
fields we are interested in, hence we have workarounds like
_nl_link_parse_info_data(). Certain features might not fully
work unless libnl supports it too (although kernel would).
As we already parse the data ourselves sometimes, just go
all they way and don't construct the intermediate libnl object.
This will allow us to drop the _nl_link_parse_info_data() workarounds
in next commits. That is important, because _nl_link_parse_info_data()
sidesteps our platform cache and is not in sync with the cache (not to
mention the extra work to explicitly refetch the data on every lookup).
Also, it gets us 60% on the way to no longer needing 'libnl-route-3.so'
at all and eventually drop requiring the library.
For link objects, nmp_object_cmp() did not consider the private fields and
thus behaved different then nmp_object_equal(). This is wrong.
Implement nmp_object_equal() based on compare.
Arguably, it is more convenient to use the static buffer as
it saves typing.
But having such a low-level function use a static buffer also
limits the way how to use it. As it was, you could not avoid
using the static buffer.
E.g. you cannot do:
char buf[100];
_LOGD ("nmp-object: %s; platform-link: %s",
nmp_object_to_string (nmpobj, buf, sizeof(buf)),
nm_platform_link_to_string (link));
This will fail for non-obvious reasons because both
to-string functions end up using the same static buffer.
Also change the to-string implementations to accept NULL
as valid and return it as "(null)".
https://bugzilla.gnome.org/show_bug.cgi?id=756427
Kernel allows to add the same IPv4 address that only differs by
peer-address (IFL_ADDRESS):
$ ip link add dummy type dummy
$ ip address add 1.1.1.1 peer 1.1.1.3/24 dev dummy
$ ip address add 1.1.1.1 peer 1.1.1.4/24 dev dummy
RTNETLINK answers: File exists
$ ip address add 1.1.1.1 peer 1.1.2.3/24 dev dummy
$ ip address show dev dummy
2: dummy@NONE: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN group default
link/ether 52:58:a7:1e:e8:93 brd ff:ff:ff:ff:ff:ff
inet 1.1.1.1 peer 1.1.1.3/24 scope global dummy
valid_lft forever preferred_lft forever
inet 1.1.1.1 peer 1.1.2.3/24 scope global dummy
valid_lft forever preferred_lft forever
We must also consider peer-address, otherwise platform will treat
two different addresses as one and the same.
https://bugzilla.gnome.org/show_bug.cgi?id=756356
After doing all the refactoring, rename the ObjectType enum to NMPObjectType.
I didn't do this earlier to avoid problems with rebasing. But since I will
backport the platform changes to nm-1-0, this is the right time to get
the name right.
After refactoring platform, nm_platform_ipx_route_get_all() and
nm_platform_ipx_address_get_all() was broken for calling with a
non-posititive ifindex (which has the meaning: ignore ifindex).
While fixing that, also refactor the NMPCacheIdType so that it matches
better the supported id-types.
Fixes: 470bcefa5f
NMPObject is a simple "object" implemenation around NMPlatformObject.
They are ref-counted and have a class-pointer. Several basic functions
like equality, hash, to-string are implemented.
NMPCache is can be used to store the NMPObject. Objects are indexed
via their primary id, but there is also multi-lookup via NMCacheId
and NMMultiIndex.
Part of the implementation is inside "nm-linux-platform.c",
because it depends on utility functions from there.
