For addresses (NMPlatformIPAddress) the @addr_source field is ignored
on a platform level. That is, all addresses inside the platform cache
have this value set to NM_IP_CONFIG_SOURCE_KERNEL. Maybe, for that reason,
the source should not be a part of the NMPlatformIPAddress structure, but
it is convenient for users to piggy back the source inside the platform
address structure.
For routes, the source is stored in NMPlatformIPRoute's @rt_source
field. When adding a route to kernel, we set the @rtm_protocol of the
route depending on the source. However, we want to map different source
values to the same protocol value.
On the other hand, when kernel sends us a route that gets put inside
the cache, we must preserve the protocol value and must not map
different protocol values to the same source.
The reason is, that a user can add two routes that only differ by
@rtm_protocol. In that sense, the @rtm_protocol fields is part of the
unique ID of a kernel route, and thus different values must map to
different sources.
Fix this, by extending the range of NMIPConfigSource to contain
a range of protocol fields.
We handle cloned routes (that have rtm_flags RTM_F_CLONED) differently.
We used to mark such routes by hacking NMIPConfigSource to have a special
value. No longer do this, because it mixes different concepts.
Note that the rt_cloned filed fits into a hole in the aligment
of NMPlatformIPRoute. Thus there is almost no overhead to this
change.
The "source" field of NMPlatformIPRoute (now "rt_source") maps to the
protocol field of the route. The source of NMPlatformIPAddress (now
"addr_source") has no direct equivalent in the kernel.
As their use is different, they should have different names. Also,
the name "source" is used all over the place. Hence give the fields
a more distinct name.
Add a new NMPNetns class. This allows creation, deletion and
switching of network namespaces. The API only offers push/pop
operations to switch the namespace. This way the API enforces
the user to always restore the previous namespace.
A NMPlatform instance not only uses the netlink socket, but also
sysfs, udev, ethtool, mii. Still, a NMPlatform instance lives
entirely inside one namespace and is not spanning multiple namespaces.
To properly support network namespaces, the platform instance must
switch the namespace as necessary, transparent to the caller.
Udev is only supported in the main namespace.
For now, network namespaces are not actually used and are disabled
via the NM_PLATFORM_NETNS_SUPPORT argument.
https://bugzilla.gnome.org/show_bug.cgi?id=762408
Most functions defined in "nm-platform-utils.h" perform a lookup
of link properties, for example via ethtool or sysfs. Those functions
depend on the system configuration, such as the current network namespace.
Move the simple helper functions away to "nm-core-internal.h", so that
all remaining functions from "nm-platform-utils.h" are really related to
somthing that interacts with the system/kernel.
It's useful to track the flags for IPv4 addresses too.
- we might want to sort IPv4 addresses according to whether they
are permanent or dynamic.
- later we want to set IFA_F_NOPREFIXROUTE also for IPv4 addresses.
While the ability to "set" a flag doesn't necessarily require that we
also keep the flags present in NMPlatformIP4Address, it is more consistent.
"NetworkManagerUtils.h" contains a bunch of helper tools for core
daemon ("src/").
Unfortunately, it has dependencies to other parts of core,
such as "nm-device.h" and "nm-platform.h". Split out a part
of tools that are independent so that they can be used without
dragging in other dependencies.
"nm-core-utils.h" should only use libnm-core, "nm-logging.h"
and shared.
"NetworkManagerUtils.h" should provide all "nm-core-utils.h" and
possibly other utilities that have larger dependencies.
There are far too many "flags". Rename the "flags" to "n_ifa_flags"
which reminds to "ifa_flags" in 'struct ifaddrmsg', but with a
distinctive "n_" prefix.
There are far too many "flags". Rename the "flags" to "n_ifi_flags"
which reminds to "ifi_flags" in 'struct ifinfomsg', but with a
distinctive "n_" prefix.
The explainations no longer hold for the most part. Documentation
that is not directly the code is bound the expire.
The code is the best documentation!! :)
Link related functions should have a "nm_platform_link" prefix. Rename.
Naming is a subjective matter and one might argue that omitting
the "link" part from the name is shorter and even preferred.
However, I think functions related to links should have a common
prefix as the underlyings are strongly related.
Let the link-add functions return the internal pointer to the platform
link object. Similar to link-get, which doesn't copy the link either.
Also adjust the sole users of the add-functions (create-and-realize)
to take the pointer.
Eventually we still copy the returned data, because accessing platform can
invalidate the returned pointer. Thus we don't actually safe any copying
by this (at least every use of the function currently leads to the data
being copied).
Still change it, because I think the API of NMPlatform should look like that.
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.
This enum was unused and meaningless because the platform signals
are emitted as a consequence of netlink messages. It is not clear
whether a netlink message was received due to an external event
or an internal action.
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).
Having a static string buffer for convenience is useful not only
for platform. Define the string buffer in NetworkManagerUtils.h,
so that all to-string functions can reuse *one* buffer.
Of course, this has the potential danger, that different
to-string method might reuse the same buffer. Hence, low-level
library functions are adviced to use their own buffer, because
an upper level might already use the global buffer for another
string.
The peer-address (IFA_ADDRESS) can also be all-zero (0.0.0.0).
That is distinct from an usual address without explicit peer-address,
which implicitly has the same peer and local address.
Previously, we treated an all-zero peer_address as having peer and
local address equal. This is especially grave, because the peer is part
of the primary key for an IPv4 address. So we not only get a property of
the address wrong, but we wrongly consider two different addresses as
one and the same.
To properly handle these addresses, we always must explicitly set the peer.
We already have nm_platform_tun_get_properties(). Rename the function
as they both sidestep the platform cache to lookup some link-specific
properties.
For recent kernels, the peer-ifindex of veths is reported as
parent (IFA_LINK). Prefer that over the ethtool lookup.
For one, this avoids the extra ethtool call which has the
downside of sidestepping the platform cache. Also, looking
up the peer-ifindex in ethtool does not report whether the
peer lifes in another netns (NM_PLATFORM_LINK_OTHER_NETNS).
Only use ethtool as fallback for older kernels.
