Sending and receiving RA is repeated periodically. Don't spam logs
with the same message again and again. Rate limit the message to 6
every 12 hours per type and per ndisc instance.
The current mess of code seems like a hodgepodge of complex ideas,
partially copied from systemd, but then subtly different, and it's a
mess. Let's simplify this drastically.
First, assume that getrandom() is always available. If the kernel is too
old, we have an unoptimized slowpath for still supporting ancient
kernels, a path that should be removed at some point. If getrandom()
isn't available and the fallback path doesn't work, the system has much
larger problems, so just crash. This should basically never happen.
getrandom() and having randomness available in general is a critical
system API that should be expected to be available on any functioning
system.
Second, assume that the rng is initialized, so that asking for random
numbers should never block. This is virtually always true on modern
kernels. On ancient kernels, it usually becomes true. But, more
importantly, this is not the responsibility of various daemons, even
ones that run at boot. Instead, this is something for the kernel and/or
init to ensure.
Putting these together, we adopt new behavior:
- First, try getrandom(..., ..., 0). The 0 flags field means that this
call will only return good random bytes, not insecure ones.
- If this fails for some reason that isn't ENOSYS, crash.
- If this fails due to ENOSYS, poll on /dev/random until 1 byte is
available, suggesting that subsequent reads from the rng will almost
have good random bytes. If this fails, crash. Then, read from
/dev/urandom. If this fails, crash.
We don't bother caching when getrandom() returns ENOSYS. We don't apply
any other fancy optimizations to the slow fallback path. We keep that as
barebones and minimal as we can. It works. It's for ancient kernels. It
should be removed soon. It's not worth spending cycles over. Instead,
the goal is to eventually reduce all of this down to a simple boring
call to getrandom(..., ..., 0).
https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/2127
Remove unused "server_name" argument. It is still possible to pass the
server name, if needed, with the nm_l3_config_data_add_nameserver()
function. After this change, rename the function to
nm_l3_config_data_add_nameserver_addr(), since the function only
accepts an address.
RFC 4191 section-3.1 says:
When processing a Router Advertisement, a type C host first updates a
::/0 route based on the Router Lifetime and Default Router Preference
in the Router Advertisement message header. [...] The Router Preference
and Lifetime values in a ::/0 Route Information Option override the
preference and lifetime values in the Router Advertisement header.
Fix the RA parsing so that the parameters from a default route option
are applied to the gateway.
https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/issues/1666https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/2072
Fixes: c3a4656a68 ('rdisc: libndp implementation')
If we add multiple default routes with the same metric and different
preferences, kernel merges them into a single ECMP route, with overall
preference equal to the preference of the first route
added. Therefore, the preference of individual routes is not
respected.
To avoid that, add routes with different metrics if they have
different preferences, so that they are not merged together.
We could configure only the route(s) with highest preference ignoring
the others, and the effect would be the same. However, it is better to
add all routes so that users can easily see from "ip route" that there
are multiple routers available.
https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/issues/1468https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1983
Fixes: 032b4e4371 ('core: use router preference for IPv6 routes')
Also check for gateway equality when deduplicate routing entries. This
allows to support multiple routes to the same network using different
gateways. This is useful for Thread networks where multiple BRs route
to the same Thread network. If one of these BRs go offline, fallback to
a different router will be much quicker if multiple entries are present.
Note that quick fallback to a different router requires IPv6
reachability probe to be active. Typically Linux disables reachability
probes on Linux machines which act as IPv6 gateway (when forwarding is
enabled).
The value can be unknown for different reasons:
- we don't have a value saved in NMDevice's "ip6_saved_properties"
because NM was restarted or because the device didn't have an
ifindex when it became managed.
- the value read from /proc is outside the allowed range (kernel
allows "echo 42 > /proc/sys/net/ipv6/conf/enp1s0/use_tempaddr")
Note that the second case was already possible before commit
797f3cafee ('device: fall back to saved use_tempaddr value instead
of rereading /proc').
If we can't determine the previous value, pass "unknown" to ndisc; it
will generate a l3cd with "unknown" ip6-privacy, which means to not
set the value when committing the configuration.
Fixes: 797f3cafee ('device: fall back to saved use_tempaddr value instead of rereading /proc')
https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1907
Background: when router sends router advertisement (RA) message,
NetworkManager processes it and passes data to a lower system layer.
Currently there is a problem that NetworkManager adds one second to both
valid lifetime and preferred lifetime. This happens because of the
algorithm in nm_ndisc_data_to_l3cd() function.
Let's look at an example: let current timestamp be 100450, so now_sec
variable is 100. At this moment RA message was received from the router.
The IPv6 address' valid lifetime is 200 seconds (for example), so
expiration timestamp (ndisc_addr->expiry_msec) is 300450. But after the
_nm_ndisc_lifetime_from_expiry() call, NMPlatformIP6Address lifetime
becomes 201 ((300450-(100*1000)+999)/1000). Which is wrong.
This commit fixes this behaviour by replacing
nm_utils_get_monotonic_timestamp_sec() with
nm_utils_get_monotonic_timestamp_msec() so that timestamps are
calculated more precisely.
Related issue: https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/issues/1464
Merge request: https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1863
(cherry picked from commit 14e7220f5f)
g_random_*() is based on GRand, which is not a CSPRNG. Instead, rely on
kernel to give us good random numbers, which is what nm_random_*() does.
Note that nm_random_*() calls getrandom() (or reads /dev/urandom), which
most likely is slower than GRand. It doesn't matter for our uses though.
It is cumbersome to review all uses of g_rand_*() whether their usage of
a non-cryptographically secure generator is appropriate. Instead, just
always use an appropriate function, thereby avoiding this question. Even
glib documentation refers to reading "/dev/urandom" as alternative. Which
is what nm_random_*() does. These days, it seems unnecessary to not use
the best random generator available, unless it's not fast enough or you
need a stable/seedable stream of random numbers.
In particular in nmcli, we used g_random_int_range() to generate
passwords. That is not appropriate. Sure, it's *only* for the hotspot,
but still.
It is possible that an ra leads to two routes having
the same prefix as well as the same prefix length.
One of them, however, refers to the on-link prefix,
and the other one to a route from the route information field.
(Moreover, they might have different route preferences.)
Hence, if both routes differ in the on-link property,
both are added, and the route from the route information
option receives a metric penalty.
Fixed#1163.
This adjusts the change from commit ffbcf01589 ('test-ndisc-fake:
free l3cfg after creating fake-ndisc').
ndisc_new() already correctly handles the reference count of l3cfg via
"gs_unref_object". The party that took the wrong reference was
nm_fake_ndisc_new().
Fixes: 58287cbcc0 ('core: rework IP configuration in NetworkManager using layer 3 configuration')
Considering nm_netns_l3cfg_acquire returns a l3cfg reference and only
keeps a weak reference we need to free l3cfg in fake-ndisc after
creating the object.
G_TYPE_CHECK_INSTANCE_CAST() can trigger a "-Wcast-align":
src/core/devices/nm-device-macvlan.c: In function 'parent_changed_notify':
/usr/include/glib-2.0/gobject/gtype.h:2421:42: error: cast increases required alignment of target type [-Werror=cast-align]
2421 | # define _G_TYPE_CIC(ip, gt, ct) ((ct*) ip)
| ^
/usr/include/glib-2.0/gobject/gtype.h:501:66: note: in expansion of macro '_G_TYPE_CIC'
501 | #define G_TYPE_CHECK_INSTANCE_CAST(instance, g_type, c_type) (_G_TYPE_CIC ((instance), (g_type), c_type))
| ^~~~~~~~~~~
src/core/devices/nm-device-macvlan.h:13:6: note: in expansion of macro 'G_TYPE_CHECK_INSTANCE_CAST'
13 | (G_TYPE_CHECK_INSTANCE_CAST((obj), NM_TYPE_DEVICE_MACVLAN, NMDeviceMacvlan))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
Avoid that by using _NM_G_TYPE_CHECK_INSTANCE_CAST().
This can only be done for our internal usages. The public headers
of libnm are not changed.
The DNS name can now also contain the DoT server name. It's not longer a
binary IP address only.
Extend NML3ConfigData to account for that. To track the additional
data, use the string representation. The alternative to have a separate
type that contains the parsed information would be cumbersome too.
A DAD failure is in most cases a symptom of a network
misconfiguration; as such it must be logged in the default
configuration (info level).
While at it, fix other log messages.
Since we evaluate platform changes in a idle handler, there can be
multiple DAD failure at the same time that must generate a single
ndisc.configuration-change signal.
The function is unused at the moment.
We already have src/linux-headers, where we have complete copies of linux
user space headers. Of course that exists, because we want to use certain
features and don't depend on the installed kernel headers. Which works
well, because kernel user space API is stable, and we anyway want to
support compiling against a newer kernel and run against an older (e.g.
in a container). So having our copy of newer kernel headers is merely
as if we compiled against as newer kernel.
Add "src/nm-compat-headers" which has a similar purpose, but a different
approach. Instead of replacing the included header entirely, include
the system header and patch it with #define.
Use this for "linux/if_addr.h". Of course, the approach here is that we
no longer include <linux/if_addr.h> directly, but instead include
"nm-compat-headers/linux/if_addr.h".
These variants provide additional nm_assert() checks, and are thus
preferable.
Note that we cannot just blindly replace &g_array_index() with
&nm_g_array_index(), because the latter would not allow getting a
pointer at index [arr->len]. That might be a valid (though uncommon)
usecase. The correct replacement of &g_array_index() is thus
nm_g_array_index_p().
I checked the code manually and replaced uses of nm_g_array_index_p()
with &nm_g_array_index(), if that was a safe thing to do. The latter
seems preferable, because it is familar to &g_array_index().
- name things related to `in_addr_t`, `struct in6_addr`, `NMIPAddr` as
`nm_ip4_addr_*()`, `nm_ip6_addr_*()`, `nm_ip_addr_*()`, respectively.
- we have a wrapper `nm_inet_ntop()` for `inet_ntop()`. This name
of our wrapper is chosen to be familiar with the libc underlying
function. With this, also name functions that are about string
representations of addresses `nm_inet_*()`, `nm_inet4_*()`,
`nm_inet6_*()`. For example, `nm_inet_parse_str()`,
`nm_inet_is_normalized()`.
<<<<
R() {
git grep -l "$1" | xargs sed -i "s/\<$1\>/$2/g"
}
R NM_CMP_DIRECT_IN4ADDR_SAME_PREFIX NM_CMP_DIRECT_IP4_ADDR_SAME_PREFIX
R NM_CMP_DIRECT_IN6ADDR_SAME_PREFIX NM_CMP_DIRECT_IP6_ADDR_SAME_PREFIX
R NM_UTILS_INET_ADDRSTRLEN NM_INET_ADDRSTRLEN
R _nm_utils_inet4_ntop nm_inet4_ntop
R _nm_utils_inet6_ntop nm_inet6_ntop
R _nm_utils_ip4_get_default_prefix nm_ip4_addr_get_default_prefix
R _nm_utils_ip4_get_default_prefix0 nm_ip4_addr_get_default_prefix0
R _nm_utils_ip4_netmask_to_prefix nm_ip4_addr_netmask_to_prefix
R _nm_utils_ip4_prefix_to_netmask nm_ip4_addr_netmask_from_prefix
R nm_utils_inet4_ntop_dup nm_inet4_ntop_dup
R nm_utils_inet6_ntop_dup nm_inet6_ntop_dup
R nm_utils_inet_ntop nm_inet_ntop
R nm_utils_inet_ntop_dup nm_inet_ntop_dup
R nm_utils_ip4_address_clear_host_address nm_ip4_addr_clear_host_address
R nm_utils_ip4_address_is_link_local nm_ip4_addr_is_link_local
R nm_utils_ip4_address_is_loopback nm_ip4_addr_is_loopback
R nm_utils_ip4_address_is_zeronet nm_ip4_addr_is_zeronet
R nm_utils_ip4_address_same_prefix nm_ip4_addr_same_prefix
R nm_utils_ip4_address_same_prefix_cmp nm_ip4_addr_same_prefix_cmp
R nm_utils_ip6_address_clear_host_address nm_ip6_addr_clear_host_address
R nm_utils_ip6_address_same_prefix nm_ip6_addr_same_prefix
R nm_utils_ip6_address_same_prefix_cmp nm_ip6_addr_same_prefix_cmp
R nm_utils_ip6_is_ula nm_ip6_addr_is_ula
R nm_utils_ip_address_same_prefix nm_ip_addr_same_prefix
R nm_utils_ip_address_same_prefix_cmp nm_ip_addr_same_prefix_cmp
R nm_utils_ip_is_site_local nm_ip_addr_is_site_local
R nm_utils_ipaddr_is_normalized nm_inet_is_normalized
R nm_utils_ipaddr_is_valid nm_inet_is_valid
R nm_utils_ipx_address_clear_host_address nm_ip_addr_clear_host_address
R nm_utils_parse_inaddr nm_inet_parse_str
R nm_utils_parse_inaddr_bin nm_inet_parse_bin
R nm_utils_parse_inaddr_bin_full nm_inet_parse_bin_full
R nm_utils_parse_inaddr_prefix nm_inet_parse_with_prefix_str
R nm_utils_parse_inaddr_prefix_bin nm_inet_parse_with_prefix_bin
R test_nm_utils_ip6_address_same_prefix test_nm_ip_addr_same_prefix
./contrib/scripts/nm-code-format.sh -F
nmp_utils_lifetime_get() calculates the lifetime of addresses,
and it bases the result on a "now" timestamp.
If you have two addresses and calculate their expiry, then we want to
base it on top of the same "now" timestamp, meaning, we should
only call nm_utils_get_monotonic_timestamp_sec() once. This is also a
performance optimization. But much more importantly, when we make a
comparison at a certain moment, we need that all sides have the same
understanding of the current timestamp.
But nmp_utils_lifetime_get() does not always require the now timestamp.
And the caller doesn't know, whether it will need it (short of knowing
how nmp_utils_lifetime_get() is implemented). So, make the now parameter
an in/out argument. If we pass in an already valid now timestamp, use
that. Otherwise, fetch the current time and also return it.
(cherry picked from commit deb37401e9)
We use clang-format for automatic formatting of our source files.
Since clang-format is actively maintained software, the actual
formatting depends on the used version of clang-format. That is
unfortunate and painful, but really unavoidable unless clang-format
would be strictly bug-compatible.
So the version that we must use is from the current Fedora release, which
is also tested by our gitlab-ci. Previously, we were using Fedora 34 with
clang-tools-extra-12.0.1-1.fc34.x86_64.
As Fedora 35 comes along, we need to update our formatting as Fedora 35
comes with version "13.0.0~rc1-1.fc35".
An alternative would be to freeze on version 12, but that has different
problems (like, it's cumbersome to rebuild clang 12 on Fedora 35 and it
would be cumbersome for our developers which are on Fedora 35 to use a
clang that they cannot easily install).
The (differently painful) solution is to reformat from time to time, as we
switch to a new Fedora (and thus clang) version.
Usually we would expect that such a reformatting brings minor changes.
But this time, the changes are huge. That is mentioned in the release
notes [1] as
Makes PointerAligment: Right working with AlignConsecutiveDeclarations. (Fixes https://llvm.org/PR27353)
[1] https://releases.llvm.org/13.0.0/tools/clang/docs/ReleaseNotes.html#clang-format
Completely rework IP configuration in the daemon. Use NML3Cfg as layer 3
manager for the IP configuration of an interface. Use NML3ConfigData as
pieces of configuration that the various components collect and
configure. NMDevice is managing most of the IP configuration at a higher
level, that is, it starts DHCP and other IP methods. Rework the state
handling there.
This is a huge rework of how NetworkManager daemon handles IP
configuration. Some fallout is to be expected.
It appears the patch deletes many lines of code. That is not accurate, because
you also have to count the files `src/core/nm-l3*`, which were unused previously.
Co-authored-by: Beniamino Galvani <bgalvani@redhat.com>
There are routers out in the wild which won't send unsolicited
router advertisements.
In the past, these setups still worked because NetworkManager
used to send router solicitations whenever the half-life of
dns servers and dns domains expired, but this has been changed
in commit 03c6d8280c ('ndisc: don't call solicit_routers()
from clean_dns_*() functions').
We will now schedule router solicitation to be started again
about one minute before advertised entities expire.
https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/997
NMNDisc has two implementations: lndp and fake. Fake only exists as a
stub for unit tests, otherwise there is no purpose to it. Also, we won't
ever add another implementation beside lndp. If lndp is not suitable, it
would be replaced, but not accompanied by a second implementation.
As such, nm_lndp_ndisc_get_sysctl() has no purpose to be in
"nm-lndp-ndisc.c". This split does not exist to abstract "nm-ndisc.c"
from NMPlatform. It exists to make it easier to test.
It's great to have functions that cannot fail, because it allows to
skip any error handling.
_set_stable_privacy() as it was could not fail, so the only reason why
nm_utils_ipv6_addr_set_stable_privacy() could fail is because the DAD
counter exhausted.
Also, it will be useful to have a function that does not do the counter
check, where the caller wants to handle that differently.
Rename some functions, and make the core nm_utils_ipv6_addr_set_stable_privacy()
not failable.
While NMUtilsIPv6IfaceId is only 8 bytes large, it seems unidiomatic to
pass the plain struct around.
With a "const NMUtilsIPv6IfaceId *" argument it is more clear what the
meaning of this is.
Change to use pointers.
The formatting produced by clang-format depends on the version of the
tool. The version that we use is the one of the current Fedora release.
Fedora 34 recently updated clang (and clang-tools-extra) from version
12.0.0 to 12.0.1. This brings some changes.
Update the formatting.
Each NML3ConfigData should have a source set, and in fact most callers
would call nm_l3_config_data_set_source() right after creating the
instance.
Move the source parameter to the new() constructor function. Also remove
the setter, making the source of an instance immutable.
As every l3cfg instance generally has a clear purpose, the source should
always be known from the start and doesn't need to change.
NMStrBuf's API is all about convenience. When you reset the buffer,
is it convenient to immediately append a new string?
It seems not. Make nm_str_buf_reset() simpler by doing only one thing.