The function should not close the input file descriptor; however
fdopen() associates the fd to the new stream so that when the stream
is closed, the fd is too. The result is a double close() and the
second call can in certain cases affect a wrong fd.
Use a duplicate fd for the stream.
Fixes: 1d9bdad1dfhttps://bugzilla.redhat.com/show_bug.cgi?id=1451236
libnm-core limits the rande for GATEWAY_PING_TIMEOUT to 0 to 600.
See commit e86f8354a7, "device: restart
ping process when it exits with an error".
The reader must not pass value out of range to g_object_set().
Clamp and warn.
"nm-dhcp-manager.h" forward declares _nm_dhcp_manager_factories.
We need to make the definition aware of the declaration, so
that the compiler can warn if they differ.
We don't need this extra distinguisher. It makes no sense to ever
compare two routes with a different compare-type.
Also, the number of fields that is hashed already differs between each
compare type. If we have a good hashing algorithm, this already suffices
that the hash value looks largely different.
We often want to cascade hashing, meaning, to combine the
outcome of various hash functions in a larger hash.
Instead of having each hash function return a guint hash value,
accept a hash state argument. This saves the overhead of initializing
and completing the intermediate hash states.
It also avoids loosing entropy when we reduce the larger hash state
into the intermediate guint hash value.
By using a macro, we don't cast all the types to guint. Instead,
we use their native types directly. Hence, we don't need
nm_hash_update_uint64() nor nm_hash_update_ptr().
Also, for types smaller then guint like char, we save hashing
the all zero bytes.
siphash24() is wildly used by projects nowadays.
It's certainly slower then our djb hashing that we used before.
But quite likely it's fast enough for us, given how wildly it is
used. I think it would be hard to profile NetworkManager to show
that the performance of hash tables is the issue, be it with
djb or siphash24.
Certainly with siphash24() it's much harder to exploit the hashing
algorithm to cause worst case hash operations (provided that the
seed is kept private). Does this better resistance against a denial
of service matter for us? Probably not, but let's better be safe then
sorry.
Note that systemd's implementation uses a different seed for each hash
table (at least, after the hash table grows to a certain size).
We don't do that and use only one global seed.
Replace the usage of g_str_hash() with our own nm_str_hash().
GLib's g_str_hash() uses djb2 hashing function, just like we
do at the moment. The only difference is, that we use a diffrent
seed value.
Note, that we initialize the hash seed with random data (by calling
getrandom() or reading /dev/urandom). That is a change compared to
before.
This change of the hashing function and accessing the random pool
might be undesired for libnm/libnm-core. Hence, the change is not
done there as it possibly changes behavior for public API. Maybe
we should do that later though.
At this point, there isn't much of a change. This patch becomes
interesting, if we decide to use a different hashing algorithm.
The privious NM_HASH_* macros directly operated on a guint value
and were thus close to the actual implementation.
Replace them by adding a NMHashState struct and accessors to
update the hash state. This hides the implementation better
and would allow us to carry more state. For example, we could
switch to siphash24() transparently.
For now, we still do a form basically djb2 hashing, albeit with
differing start seed.
Also add nm_hash_str() and nm_str_hash():
- nm_hash_str() is our own string hashing implementation
- nm_str_hash() is our own string implementation, but with a
GHashFunc signature, suitable to pass it to g_hash_table_new().
Also, it has this name in order to remind you of g_str_hash(),
which it is replacing.
"nm-utils/nm-shared-utils.h" shall contain utility function without other
dependencies. It is intended to be used by other projects as-is.
nm_utils_random_bytes() requires getrandom() and a HAVE_GETRANDOM configure
check. That makes it more cumbersome to re-use "nm-shared-utils.h", in
cases where you don't care about nm_utils_random_bytes().
Split nm_utils_random_bytes() out to a separate file.
Same for hash utils, which depend on nm_utils_random_bytes(). Also, hash
utils will eventually be extended to use siphash24.
Introduce a NM_HASH_INIT() function. It makes the places
where we initialize a hash with a certain seed visually clear.
Also, move them from "shared/nm-utils/nm-shared-utils.h" to
"shared/nm-utils/nm-macros-internal.h". We might want to
have NM_HASH_INIT() non-inline (hence, define it in the
source file).
Add a new function nm_utils_random_bytes().
This function now preferably uses getrandom() syscall if it is
available.
As fallback, it always tries to fill the buffer from /dev/urandom.
If it cannot, as last fallback it uses GRand, which cannot fail.
Hence, the function always sets some (pseudo) random bytes.
It also returns FALSE if the obtained bytes are possibly not good
randomness.
For routes and the default-route from NDisc, set the router preference
RTA_PREF.
Also, previously, we would only configure one IPv6 default-route. That by itself
was not really a problem, as long as NetworkManager would always make sure that
it configured the route to the ~best~ router.
Actually, NM should have done that already. It keeps the list of gateways
sorted, and prefers them according to their preference. But maybe
it didn't, so we have bug rh#1445417 (??).
Change that by configuring a default-route for all gateways, with
appropriate router prefrence. In case, kernel doesn't support RTA_PREF
yet, only configure all routes that share the same maxiumum preference.
https://bugzilla.redhat.com/show_bug.cgi?id=1445417
- add assert code to check that our internal tracking of
the gateways is consistent.
- assert (gracefully) against libndp returning :: as gateway
address.
We encounter the same enum in 3 forms:
- NMNDiscPreference in NetworkManager
- "enum ndp_route_preference" in <ndp.h>
- ICMPV6_ROUTER_PREF_* in <linux/icmpv6.h>
Move our enum to nm-core-utils.h, so that it can be used
by platform code as well (platform code should not include
ndisc/nm-ndisc.h).
Also, NMNDiscPreference was not numerically identical to their
native values (meaning: it shuffled the names and numbers).
Make them all numerically equal, so that they can be used in
the same context.
This means, while previously we could compare NMNDiscPreference
directly according to their priority, we now need _preference_to_priority().
On the other hand, we could omit translate_preference() -- but actually,
we still have _route_preference_coerce() because pref comes from libndp
and is thus untrusted. We still have to range check it.
We have the timestamp nm_utils_get_monotonic_time_s(), which should be
gint32 type. Then we also have timestamps in the NMNDisc* objects, which
consist of guint32 timestamp and lifetime.
Cleanup handling the times and calculation of the timestamps by using
the correct integer type consistently and ensuring that no integer overflow
occurs.
The @i variable to loop over the arrays should have the same type as
GArray.len, to which it is compared. In this case "guint".
As we remove items from the arrays while iterating over it, it gets
a bit complicated either way. I disliked that
g_array_remove_index (rdata->gateways, i--);
would underflow for unsigned integers. While that would work fine,
I think that is confusing. So, the variable is no longer incremented
in the increment statement of the for loop.
The bus manager takes extra references to the GDBusConnection every
time g_dbus_object_manager_server_get_connection() its called,
preventing its disposal once the connection is closed. This causes a
leak for each DHCP event.
https://bugzilla.redhat.com/show_bug.cgi?id=1461643
Before commit 650a7022c1, we would
always forego using getrandom(). That changed, and now we detect
at compile time whether getrandom() is provided by libc. So, if you
build against recent libc, we use it too.
However, systemd's src/basic/missing_syscall.h also provides getrandom() by
calling the syscall directly. We don't do that, because it seems too cumbersome
to maintain.
Fixes: 650a7022c1
Instead of having 3 properties @gateway, @never_default and @has_gateway
on NMIP4Config/NMIP6Config that determine the default-route, track the
default-route as a regular route.
The gateway setting is the configuration knob for the default-route.
Since an NMIP4Config/NMIP6Config instance only has one gateway property,
it cannot track more then one default-routes (see related bug rh#1445417).
Especially with policy routing, it might be interesting to configure a
default-route in multiple tables.
Also, later it might be interesting to allow adding default-routes as
regular static routes in a connection, so that the user can configure additional
route parameters for the default-route or add default-routes in multiple tables.
With this patch, default-routes now have a rt_source property according to their
origin.
Also, the previous commits of this branch broke handling of the
default-route :) . That should be working now again.
It's not needed. Whenever we add a route, we pass in the
route metric (for example, based on the device's configuration).
No need to merge and track it into the NMIP4Config/NMIP6Config.
The metric was only used in nm_ip4_config_create_setting()
and nm_ip6_config_create_setting(). In fact it's wrong to do
that, because it means we first capture some settings, and guess
the configured route metric. But we cannot do that. Our best
guess what a configured setting might be is -1.
The MSS is only set for VPN connections (by merging it in the respective
NMIP4Config/NMIP6Config).
It is also only used when setting the MSS of the default route.
Don't track that property in NMIP4Config/NMIP6Config, instead, set the
mss of the route directly in nm_vpn_connection_ip4_config_get() and
nm_vpn_connection_ip6_config_get().
There is a potential change in behavior here: NMDevice also consisdered
the MSS for the default route, but that would only be set if the MSS
gets merged from an vpn-ip-config. Which at most is the case for
iterface-less VPN types (libreswan). But even in that case, it doesn't
seem right to me to use the VPN's MSS for the device's default-route.
We added "ipv4.route-table-sync" and "ipv6.route-table-sync" to not change
behavior for users that configured policy routing outside of NetworkManager,
for example, via a dispatcher script. Users had to explicitly opt-in
for NetworkManager to fully manage all routing tables.
These settings were awkward. Replace them with new settings "ipv4.route-table"
and "ipv6.route-table". Note that this commit breaks API/ABI on the unstable
development branch by removing recently added API.
As before, a connection will have no route-table set by default. This
has the meaning that policy-routing is not enabled and only the main table
will be fully synced. Once the user sets a table, we recognize that and
NetworkManager manages all routing tables.
The new route-table setting has other important uses: analog to
"ipv4.route-metric", it is the default that applies to all routes.
Currently it only works for static routes, not DHCP, SLAAC,
default-route, etc. That will be implemented later.
For static routes, each route still can explicitly set a table, and
overwrite the per-connection setting in "ipv4.route-table" and
"ipv6.route-table".
- merge the IPv4 and IPv6 implementations. They are for the most
part identical. Also, they are independent of NMIP4Config/NMIP6Config.
- parse the entire file at once. Don't parse it twice, once for the
name servers and once for the options. This also avoids loading
/etc/resolv.conf twice, as it would be done before.
These static variables really never be modified.
Mark them as const, which allows the linker to mark them as
read-only.
The problem is libnl3's API, which has these parameters
not as const. Add a workaround for that. Clearly libnl3 is
not gonna modify the policy, that the API was fixed too [1]
[1] b4802a17a7
The line
device (wlan0): state change: ip-config -> ip-check (reason none, internal state managed)
prints the sys-iface-state, which is at other places logged with
device[0x55914506ed70] (wlan0): sys-iface-state: external -> managed
For consistency, name the same parameter the same.
The name "priority" is well established for routes (e.g. kernel's
RTA_PRIORITY netlink attribute).
However, we call it at most places "metric" or "route_metric".
Rename it, not to use two different names for the same thing.
The name nm_device_get_priority() is misleading. Nowadays it's only used
for the default route metric, and nothing else.
Rename it, and make it static.
One might already question the existance of nm_utils_parse_inaddr_bin(),
because it only wraps inet_pton(), which by itself isn't terrible API.
The reason nm_utils_parse_inaddr_bin() exists, is to mirror to nm_utils_parse_inaddr()
function, which has additional functionality on top of inet_pton().
But we shouldn't have more then one wrapper for inet_pton().
