Use %u for unsigned type and cast the guint32 to (unsigned).
While at it, increase the stack-allocated buffer to 64 bytes
(it doesn't hurt) and use nm_sprintf_buf().
We allow to reapply a connection with different id, uuid, stable-id, autoconnect value.
This is allowed for convenience, so that a user can reapply a connection that differs
in these fields. But actually, these fields cannot be reapplied. That
is, their new values are not considered and the old values are continued
to be used.
Thus, mangle the reapplied connection to use the original, actually used
values.
The stable-id for one activation cannot actually change. This is also, because we cache it
as priv->current_stable_id. Still, allow reapply with a differing stable-id for convenience.
Usecase: when connecting to a public Wi-Fi with MAC address randomization
("wifi.cloned-mac-address=random") you get on every re-connect a new
IP address due to the changing MAC address.
"wifi.cloned-mac-address=stable" is the solution for that. But that
means, every time when reconnecting to this network, the same ID will
be reused. We want an ID that is stable for a while, but at a later
point a new ID should e generated when revisiting the Wi-Fi network.
Extend the stable-id to become dynamic and support templates/substitutions.
Currently supported is "${CONNECTION}", "${BOOT}" and "${RANDOM}".
Any unrecognized pattern is treated verbaim/untranslated.
"$$" is treated special to allow escaping the '$' character. This allows
the user to still embed verbatim '$' characters with the guarantee that
future versions of NetworkManager will still generate the same ID.
Of course, a user could just avoid '$' in the stable-id unless using
it for dynamic substitutions.
Later we might want to add more recognized substitutions. For example, it
could be useful to generate new IDs based on the current time. The ${} syntax
is extendable to support arguments like "${PERIODIC:weekly}".
Also allow "connection.stable-id" to be set as global default value.
Previously that made no sense because the stable-id was static
and is anyway strongly tied to the identity of the connection profile.
Now, with dynamic stable-ids it gets much more useful to specify
a global default.
Note that pre-existing stable-ids don't change and still generate
the same addresses -- unless they contain one of the new ${} patterns.
The only implementations were there for tracking the parent device.
That is now donw via nm_device_parent_*(), parent_changed_notify()
and _parent_notify_changed().
Multiple subclasses have a parent/link interface (NMDeviceIPTunnel,
NMDeviceVlan). Tracking the parent interface properly is midly
complicated to get right. So, instead of repeating it in each
subclass, track it in the parent device.
Move the updating/setting of the ip-ifindex/ip-iface to one place.
Properties should be for the most part immutable/read-only, and only
at particular places modified. That way, it's easier to track who
changes a property.
Also, add a logging line with "ip-ifname" prefix.
Most implementations of realize_start_notify() do the same
for link_changed().
Let NMDevice's base implementation of realize_start_notify() call
link_changed() -- which by default does notthing. This allows subclasses
to only overwrite link_changed().
All implementations of link_changed() chain up to NMDevice's
base implementation. Thus, everybody wants to set the carrier.
Refactor the code to set the carrier outside of link_changed().
This makes it easier to install the files with proper names.
Also, it makes the makefile rules slightly simpler.
Lastly, the documentation is now generated into docs/api, which makes it
possible to get rid of the awkward relative file names in docbook.
Keep the include paths clean and separate. We use directories to group source
files together. That makes sense (I guess), but then we should use this
grouping also when including files. Thus require to #include files with their
path relative to "src/".
Also, we build various artifacts from the "src/" tree. Instead of having
individual CFLAGS for each artifact in Makefile.am, the CFLAGS should be
unified. Previously, the CFLAGS for each artifact differ and are inconsistent
in which paths they add to the search path. Fix the inconsistency by just
don't add the paths at all.
When the device has an IP interface different from the main one, we
previously took the MTU saved in priv->mtu (which is the MTU initially
set on the underlying interface) and applied it to the IP interface.
This is wrong as it forces the two MTUs to be equal and breaks
connectivity for devices with encapsulation (as PPP). Instead, track
the two MTUs in different variables.
https://bugzilla.redhat.com/show_bug.cgi?id=1385198
It is a bit fragile not to clone the string because we depend on
nm_ip6_config_get_search(priv->ip6_config) to be stable.
In practice, it's no problem. Saves an additional strdup and the
effort to cleanup the memory afterwards.
- only record @now timestamp if we actually need it.
- use gint32 for @now. It seems wrong that NMNDiscDNSServer
uses guint32 for the timestamp. We keep
nm_utils_get_monotonic_timestamp_s() as gint32 for a reason.
- ensure the arrays are initialized to zero. E.g.
ndisc_addr->dad_counter was uninitalized.
- set the size for arrays outside the loop
- use g_array_unref(). I think that is usually better. It makes
only a difference when somebody else holds a reference to the
array. And in that case, it usually seems better not to clear
the array, just release your refrence.
There's two parts of the configuration involved: the subnet addresses
and the DNS information.
For the addressing, the shared (downlink) device signals the policy needs for a
/64 subnet. When it gets one, it merges it into the autoconf configuration and
forwards to the NDisc. When more prefixes are needed, the (uplink) device asks
the DHCP manager and eventually signals delegation (reception) of a prefix.
The NMDevice only provides the mechanism, the actual subnetting needs to
be done by the NMPolicy.
For the DNS configuration, the shared device just copies it from
whichever device the policy deems suitable.
Utilizes RFC 3633 prefix option in role of requesting router to ask the
delegating router for prefixes. In future we'll be able to use the
addresses from those prefixes on ipv6.method=shared connections.
This esentially causes us to announce the prefixes of the addresses we
own and the DNS configuration.
Currently the only way to get the IPv6 configuration on such device is
manual setting in the connection. This will change with IPv6 prefix
delegation.
The ndisc config can now be changed by NMDevice as well when the NDisc
is in ROUTER mode. But what we're really interested in is when we
receive a new one from the outside.
We'll soon not only do the router discovery, but announce ourselves as a
reouter. "Neighbor discovery" sounds to be a more appropriate name for
the class than "Router discovery".
For example for tun devices we get a lot of
(tun7): hw-addr: failed reading current MAC address
warnings. Just be silent about it. We log when something
changes, we don't need to log when we fail to obtain
a MAC address.
Thereby, refactor nm_device_update_hw_address() to return early.
The unmanaged flags PLATFORM_INIT indicates whether UDEV is done
initializing the device. We should not handle IP config changes
before that pointer.
This avoids codepaths that require the permanent MAC address of the
device. We should not freeze the permanent MAC address before
UDEV initialized the device, for two reasons:
- getting the permanent MAC address using ethtool is racy as
UDEV might still rename the interface.
- freezing a fake permanent MAC address should only happen after
UDEV is done configuring the MAC address of software devices.
#0 0x000055555568bc7a in nm_device_update_permanent_hw_address (self=self@entry=0x555555f0fb70 [NMDeviceVeth], force_freeze=force_freeze@entry=1) at src/devices/nm-device.c:11817
#1 0x000055555568c443 in nm_device_get_permanent_hw_address_full (self=self@entry=0x555555f0fb70 [NMDeviceVeth], force_freeze=force_freeze@entry=1, out_is_fake=out_is_fake@entry=0x0)
at src/devices/nm-device.c:12227
#2 0x000055555568cb06 in nm_device_get_permanent_hw_address (self=self@entry=0x555555f0fb70 [NMDeviceVeth]) at src/devices/nm-device.c:12237
#3 0x000055555568cb50 in spec_match_list (self=0x555555f0fb70 [NMDeviceVeth], specs=0x555555a5c000 = {...}) at src/devices/nm-device.c:12294
#4 0x00005555556a4ee6 in spec_match_list (device=0x555555f0fb70 [NMDeviceVeth], specs=0x555555a5c000 = {...}) at src/devices/nm-device-ethernet.c:1461
#5 0x00005555556978db in nm_device_spec_match_list (self=self@entry=0x555555f0fb70 [NMDeviceVeth], specs=0x555555a5c000 = {...}) at src/devices/nm-device.c:12277
#6 0x000055555558e187 in _match_section_infos_lookup (match_section_infos=0x555555a5d500, keyfile=0x555555a46f80, property=property@entry=0x555555793123 "ipv4.route-metric", device=device@entry=0x555555f0fb70 [NMDeviceVeth], out_value=out_value@entry=0x7fffffffe018) at src/nm-config-data.c:1169
#7 0x00005555555922ca in nm_config_data_get_connection_default (self=0x555555a548c0 [NMConfigData], property=property@entry=0x555555793123 "ipv4.route-metric", device=device@entry=0x555555f0fb70 [NMDeviceVeth]) at src/nm-config-data.c:1234
#8 0x00005555556790cd in _get_ipx_route_metric (self=self@entry=0x555555f0fb70 [NMDeviceVeth], is_v4=is_v4@entry=1) at src/devices/nm-device.c:1142
#9 0x000055555567912e in nm_device_get_ip4_route_metric (self=self@entry=0x555555f0fb70 [NMDeviceVeth]) at src/devices/nm-device.c:1161
#10 0x000055555567da6c in ip4_config_merge_and_apply (self=self@entry=0x555555f0fb70 [NMDeviceVeth], config=config@entry=0x0, commit=commit@entry=0, out_reason=out_reason@entry=0x0)
at src/devices/nm-device.c:4787
#11 0x000055555567e0fb in update_ip4_config (self=self@entry=0x555555f0fb70 [NMDeviceVeth], initial=initial@entry=0) at src/devices/nm-device.c:9532
#12 0x0000555555693acd in queued_ip4_config_change (user_data=0x555555f0fb70) at src/devices/nm-device.c:9651
#13 0x00007ffff4c966ba in g_main_context_dispatch (context=0x555555a46af0) at gmain.c:3154
#14 0x00007ffff4c966ba in g_main_context_dispatch (context=context@entry=0x555555a46af0) at gmain.c:3769
#15 0x00007ffff4c96a70 in g_main_context_iterate (context=0x555555a46af0, block=block@entry=1, dispatch=dispatch@entry=1, self=<optimized out>) at gmain.c:3840
#16 0x00007ffff4c96d92 in g_main_loop_run (loop=0x555555a47400) at gmain.c:4034
#17 0x000055555558372a in main (argc=<optimized out>, argv=<optimized out>) at src/main.c:411
Before the link is initialized, that is before UDEV completed
initializing the device, we should not evaluate the user-settings
unmanaged flags.
The reason is, that evaluating it likely involves looking at the
permanent MAC address, which might use the wrong fake MAC address
(before UDEV set the right one). Also, it might use the wrong ifname
to lookup the permanent MAC address via ethtool.
The permanent MAC address of an NMDevice shall not change as
long as the device is realized. That is, we read it only once
and don't change it afterwards.
There are two issues that this commit tries to mitigate:
(1) users are advised to use UDEV to rename interfaces. As we lookup
the permenent MAC address using ethtool (which uses the interface
name), there is a race where we could read the permanent MAC
address using the wrong interface name. We should wait until
UDEV finished initializing the device and until the interface
name is stable (see rh#1388286).
This commit still cannot avoid the race of ethtool entirely. It only
tries to avoid ethtool until UDEV has done its work. That is, until we
expect the interface name no longer to change.
(2) some device types, don't have a permanent MAC address so we fall
back to use the currently set address (fake). Again, users are advised
to use UDEV to configure the MAC addresses on such software devices.
Thus, we should not get the fake MAC address until UDEV initialized
the device.
This patch actually doesn't solve the problem at all yet.
The reason is that a regular caller of nm_device_get_permanent_hw_address() can
not afford to wait until UDEV settled. Thus, any user who requests the
permanent MAC address before the link is initialized, runs into the
problems above.
In a next step, we shall revisit such calls to nm_device_get_permanent_hw_address()
and delay them until the link is initialized.
We repeatedly call nm_device_update_hw_address() to reset the cached
MAC address of the device. However, we don't allow changing the address
length once it is set.
Multiple entities (initial, current and permanent MAC address) are all
checked to have the same address length. Changing the length would be a
very strange thing (and probably indicate a bug somewhere else).
Just don't allow that.
On devices that have no real permanent hardware address (as returned
by ethtool), we take the current MAC address of the device.
Currently, NM is a bit flaky about whether to accept such fake permanent
addresses for settings like keyfile.unmanaged-devices or the per-
connection property ethernet.mac-address. Probably, we should allow
using fake addresses there in general.
However, that leads to problems because NetworkManager itself changes
the current MAC address of such devices. For example when
configuing
keyfile.unmanaged-device=22:33:44:55:66:77
and later activating a connection with
ethernet.cloned-mac-address=22:33:44:55:66:77
we have a strange situation after restart and the device becomes
unmanaged.
We are going to avoid that, by remembering the fake permanent address
in the device state file.
This only matters:
- for devices that don't have a real permanent address (veth)
- if the user or NetworkManager itself changed the MAC address
of the device
- after a restart of NetworkManager, without reboot. A reboot
clears the device state for /var/run/NetworkManager.
