NMPNetns instances are immutable, hence they can be easily shared
between threads. All we need, is that the stack of namespaces is
thread-local.
Also note that NMPNetns uses almost no other API, except some bits from
"shared/nm-utils/" and nm-logging. These parts are already supposed to
be thread-safe.
The only complications is that when the thread exits, we need to
destroy the NMPNetns instances. That is especially important because
they hold file descriptors. This is accomplished using pthread's
thread-specific data. An alternative would be C11 threads' tss_create(),
but not all systems that we run against support that yet. This means,
we need to link with pthreads, but we already do that anyway.
Note that glib also requires pthreads. So, we don't get an additional
dependency here.
NetworkManager is single-threaded and uses a mainloop.
However, sometimes we may need multiple threads. For example, we will
need to write sysctl values asynchronously, using the glib thread-pool.
For that to work, we also need to switch the network-namespace of the
thread-pool thread. We want to use NMPNetns for that. Hence it's better
to have NMPNetns thread-safe, instead of coming up with a duplicate
implementation. But NMPNetns may want to log, so we also need nm-logging
thread-safe.
In general, code under "shared/nm-utils" and nm-logging should be usable
from multiple threads. It's simpler to make this code thread-safe than
re-implementing it. Also, it's a bad limitation to be unable to log
from other threads. If there is an error, the best we can often do is to
log about it.
Make nm-logging thread-safe. Actually, we only need to be able to log
from multiple threads. We don't need to setup or configure logging from
multiple threads. This restriction allows us to access logging from the
main-thread without any thread-synchronization (because all changes in
the logging setup are also done from the main-thread).
So, while logging from other threads requires a mutex, logging from the
main-thread is lock-free.
Instead of having two functions nm_logging_set_syslog_identifier()
and nm_logging_set_prefix(), merge them.
They must both be called at earliest point and together. No point
in giving them the appearance that they could be called any time.
This variable has other requirements for multi-threaded access (it will
only be accessible from the main-thread). Move it to a separate global
variable to make that clearer.
The distinction between only reading static data and modifying it,
is important when making nm-logging thread-safe.
This change should make it easier to find the places where we modify
data.
@level_desc and @domain_desc are two immutable arrays with information
about logging levels and logging domains. Since they are immutable and
intialized from the start, they are pretty trival w.r.t. tread-safety and
general maintainability (code readability).
Refactor them to be separate variables.
Previously, _nm_logging_clear_platform_logging_cache was an extern variable,
and NMLinuxPlatform would set it to a function pointer at certain points.
That's unnecessary complex, also when trying to make nm-logging thread-safe,
it's just more global variables that need to be considered. Don't do it
that way, but just link in a regular function.
Since commit 9ecdba316 ('platform: create netlink messages directly
without libnl-route-3') we're unconditionally setting IFA_ADDRESS to
the peer address, even if there's no peer and it's all zeroes.
The kernel actually stopped caring somewhere around commit caeaba790
('ipv6: add support of peer address') in v3.10, but Ubuntu Touch likes
to run Android's v3.4 on some poorly supported hardware.
Fixes: 9ecdba316chttps://gitlab.freedesktop.org/NetworkManager/NetworkManager/merge_requests/77
- use cleanup attribute to free memory
- return floating reference from _nm_connection_for_each_secret().
It's more idiomatic that a function that constructs a variant and
returns it, returns a floating variant.
_nm_connection_for_each_secret() (formerly for_each_secret()) and
_nm_connection_find_secret() (formerly find_secret()) operate on a
GVariant of secrets. For that, they implement certain assumptions
of how to handle secrets. For example, it must special-case VPN settings,
because there is no generic abstraction to handle regular secret and VPN
secrets the same.
Such special casing should only be done in libnm-core, at one place.
Move the code to libnm-core as internal API.
nm_setting_get_secret_flags() looks whether we have a suitable "-flags"
data value, or whether we have a secret with that name.
In fact, we know this is a valid secret-name. Even if there are no secret-flags
and the secret (currently) does not exists. We shall not care about the
return value.
Note that nm_setting_get_secret_flags() also for non-secrets will set
the flags to "NONE", which is just what we need.
When the parent device has a device default route (i.e. without
gateway) and we establish a VPN on top of it, 'ip route get' for the
VPN gateway returns a device route, which is the same result we get
for an unreachable VPN gateway. However it is necessary to add the
route to the gateway or otherwise it will possibly become unreachable
once the VPN gets activated.
https://gitlab.freedesktop.org/NetworkManager/NetworkManager/issues/93
We named the types inconsistently:
- "p2p-wireless" ("libnm-core/nm-setting-p2p-wireless.h")
- "p2p" ("libnm/nm-p2p-peer.h")
- "p2p-wifi" ("src/devices/wifi/nm-device-p2p-wifi.h")
It seems to me, "libnm/nm-p2p-peer.h" should be qualified with a "Wi-Fi"
specific name. It's not just peer-to-peer, it's Wi-Fi P2P.
Yes, there is an inconsistency now, because there is already
"libnm/nm-access-point.h".
It seems to me (from looking at the internet), that the name "Wi-Fi P2P"
is more common than "P2P Wi-Fi" -- although both are used. There is also
the name "Wi-Fi Direct". But it's not clear which name should be
preferred here, so stick to "Wi-Fi P2P".
In this first commit only rename the files. The following commit will
rename the content.
We don't need to remember (and compare) all the bytes that we received.
We can just compare them right away, and remember how many good bytes
we received.
Since we only compare that the HTTP response starts with the expected
response, we need to handle the empty expected response specially
(because, every response has "" as prefix).
So now if connectivity.response is set to "" (empty) we accept:
- HTTP status code 204. We ignore and accept any extra data that we
might receive.
- HTTP status code 200 and an empty (or no) body.
Discovered by GCC 9:
src/ppp/nm-ppp-manager.c: In function ‘_ppp_manager_start’:
./src/nm-logging.h:59:9: error: ‘%s’ directive argument is null [-Werror=format-overflow=]
Fixes: 35d9169c3c
The caller may not wish to replace existing peers, but only update/add
the peers explicitly passed to nm_platform_link_wireguard_change().
I think that is in particular interesting, because for the most part
NetworkManager will configure the same set of peers over and over again
(whenever we resolve the DNS name of an IP endpoint of the WireGuard
peer).
At that point, it seems disruptive to drop all peers and re-add them
again. Setting @replace_peers to %FALSE allows to only update/add.
We still don't use getnameinfo(). This is used for logging,
where we want to see a string representation that is as close
as possible to the actual bytes (to spot differences). It should
not be obfuscated by a libc function out of our control.
Also fix the notation for the IPv6 scope ID to use the common '%'
character.
Add cmp/hash functions that correctly honor the well known fields, instead
of doing memcmp/memcpy of the entire sockaddr structure.
Also, move the set function to nm_sock_addr_union_cpy() and
nm_sock_addr_union_cpy_untrusted(). This also gets it right
to ensure all bytes of the union are initialized (to zero).
When the supplicant does not support PMF we wrongly set
'ieee80211w=0', but since the option is not recognized the connection
fails. Don't set it when unsupported.
Fixes: a9ab50efb1
NM_UTILS_LOOKUP_STR() uses alloca(). Partly to avoid the overhead of
malloc(), but more important because it's convenient to use. It does
not require to declare a varible to manage the lifetime of the heap
allocation.
It's quite safe, because the stack allocation is of a fixed size of only
a few bytes. Overall, I think the convenience that we get (resulting in
simpler code) outweighs the danger of stack allocation in this case. It's
still worth it.
However, as it uses alloca(), it still must not be used inside a (unbound)
loop and it is obviously a macro.
Rename the macros to have a _A() suffix. This should make the
peculiarities more apparent.
The only purpose of using alloca() to avoid the overhead of heap-allocation
and possible save a line in source code for managing/freeing the heap allocation.
For tests we don't care about performance, and (in this case)
the code does not get any shorter.
Avoid alloca() in tests, because alloca() is something to search for
when reviewing code for stack overflows. No need to have such false
positives show up in tests.
Add a version of nm_utils_strbuf_append_*() that does not care
about NUL terminate strings, but accept any binary data. That makes
it useful for writing a binary buffer.
Add a "a{sv}" output argument to "AddAndActivate2" D-Bus API.
"AddAndActivate2" replaces "AddAndActivate" with more options.
It also has a dictionary argument to be forward compatible so that we
hopefully won't need an "AddAndActivate3". However, it lacked a similar
output dictionary. Add it for future extensibility. I think this is
really to workaround a shortcoming of D-Bus, which does provide strong
typing and type information about its API, but does not allow to extend
an existing API in a backward compatible manner. So we either resort to
Method(), Method2(), Method3() variants, or a catch-all variant with a
generic "a{sv}" input/output argument.
In libnm, rename "nm_client_add_and_activate_connection_options()" to
"nm_client_add_and_activate_connection2()". I think libnm API should have
an obvious correspondence with D-Bus API. Or stated differently, if
"AddAndActivateOptions" would be a better name, then the D-Bus API should
be renamed. We should prefer one name over the other, but regardless
of which is preferred, the naming for D-Bus and libnm API should
correspond.
In this case, I do think that AddAndActivate2() is a better name than
AddAndActivateOptions(). Hence I rename the libnm API.
Also, unless necessary, let libnm still call "AddAndActivate" instead of
"AddAndActivate2". Our backward compatibility works the way that libnm
requires a server version at least as new as itself. As such, libnm
theoretically could assume that server version is new enough to support
"AddAndActivate2" and could always use the more powerful variant.
However, we don't need to break compatibility intentionally and for
little gain. Here, it's easy to let libnm also handle old server API, by
continuing to use "AddAndActivate" for nm_client_add_and_activate_connection().
Note that during package update, we don't restart the currently running
NetworkManager instance. In such a scenario, it can easily happen that
nmcli/libnm is newer than the server version. Let's try a bit harder
to not break that.
Changes as discussed in [1].
[1] https://gitlab.freedesktop.org/NetworkManager/NetworkManager/merge_requests/37#note_79876
Don't return success from a nested code path. Handle all errors
first, and return early. Well, we cannot really return right away
because we need to handle the failure. So, at least, check for errors
and "goto fail".
