Policy routing rules are global, and unlike routes not tied to an interface by ifindex.
That means, while we take full control over all routes of an interface during a sync,
we need to consider that multiple parties can contribute to the global set of rules.
That might be muliple connection profiles providing the same rule, or rules that are added
externally by the user. NMPRulesManager mediates for that.
This is done by NMPRulesManager "tracking" rules.
Rules that are not tracked by NMPRulesManager are completely ignored (and
considered externally added).
When tracking a rule, the caller provides a track-priority. If multiple
parties track a rule, then the highest (absolute value of the) priority
wins.
If the highest track-priority is positive, NMPRulesManager will add the rule if
it's not present.
When the highest track-priority is negative, then NMPRulesManager will remove the
rule if it's present (enforce its absence).
The complicated part is, when a rule that was previously tracked becomes no
longer tracked. In that case, we need to restore the previous state.
If NetworkManager added the rule earlier, then untracking the rule
NMPRulesManager will remove the rule again (restore its previous absent
state).
By default, if NetworkManager had a negative tracking-priority and removed the
rule earlier (enforced it to be absent), then when the rule becomes no
longer tracked, NetworkManager will not restore the rule.
Consider: the user adds a rule externally, and then activates a profile that
enforces the absence of the rule (causing NetworkManager to remove it).
When deactivating the profile, by default NetworkManager will not
restore such a rule! It's unclear whether that is a good idea, but it's
also unclear why the rule is there and whether NetworkManager should
really restore it.
Add weakly tracked rules to account for that. A tracking-priority of
zero indicates such weakly tracked rules. The only difference between an untracked
rule and a weakly tracked rule is, that when NetworkManager earlier removed the
rule (due to a negative tracking-priority), it *will* restore weakly
tracked rules when the rules becomes no longer (negatively) tracked.
And it attmpts to do that only once.
Likewise, if the rule is weakly tracked and already exists when
NMPRulesManager starts posively tracking the rule, then it would not
remove again, when no longer positively tracking it.
- fix the argument type to be "gint32" and not "int".
- assert in nmp_rules_manager_track_default() for the input
arguments.
- use boolean bitfield in private data.
The name "priority" is overused. Also rules have a "priority", but that'
something else.
Rename the priority of how rules are tracked by NMPRuleManager to
"track_priority".
All that setting track-default does, is calling nmp_rules_manager_track_default()
when the rules are first accessed.
That is not right API. Since nmp_rules_manager_track_default() is already public
API (good), every caller that wishes this behavior should track these routes explicitly.
The call to nm_utils_parse_variant_attributes() is useless. The following
_tc_read_common_opts() call does the same thing. This was probably left
in place by accident.
Before:
# nmcli c modify eth666 tc.qdiscs root
Error: failed to modify tc.qdiscs: '(null)' is not a valid kind The valid syntax is: '[root | parent <handle>] [handle <handle>] <qdisc>'.
After:
# nmcli c modify eth666 tc.qdiscs root
Error: failed to modify tc.qdiscs: kind is missing. The valid syntax is: '[root | parent <handle>] [handle <handle>] <kind>'.
==16725==ERROR: AddressSanitizer: global-buffer-overflow on address 0x0000005a159f at pc 0x00000046fc1b bp 0x7fff6038f900 sp 0x7fff6038f8f0
READ of size 1 at 0x0000005a159f thread T0
#0 0x46fc1a in _do_test_unescape_spaces libnm-core/tests/test-general.c:7791
#1 0x46fe5b in test_nm_utils_unescape_spaces libnm-core/tests/test-general.c:7810
#2 0x7f4ac5fe7fc9 in test_case_run gtestutils.c:2318
#3 0x7f4ac5fe7fc9 in g_test_run_suite_internal gtestutils.c:2403
#4 0x7f4ac5fe7e83 in g_test_run_suite_internal gtestutils.c:2415
#5 0x7f4ac5fe7e83 in g_test_run_suite_internal gtestutils.c:2415
#6 0x7f4ac5fe8281 in g_test_run_suite gtestutils.c:2490
#7 0x7f4ac5fe82a4 in g_test_run (/lib64/libglib-2.0.so.0+0x772a4)
#8 0x48240d in main libnm-core/tests/test-general.c:7994
#9 0x7f4ac5dc9412 in __libc_start_main (/lib64/libc.so.6+0x24412)
#10 0x423ffd in _start (/home/bgalvani/work/NetworkManager/libnm-core/tests/test-general+0x423ffd)
0x0000005a159f is located 49 bytes to the right of global variable '*.LC370' defined in 'libnm-core/tests/test-general.c' (0x5a1560) of size 14
'*.LC370' is ascii string 'nick-5, green'
0x0000005a159f is located 1 bytes to the left of global variable '*.LC371' defined in 'libnm-core/tests/test-general.c' (0x5a15a0) of size 1
'*.LC371' is ascii string ''
SUMMARY: AddressSanitizer: global-buffer-overflow libnm-core/tests/test-general.c:7791 in _do_test_unescape_spaces
Leak detection adds unhelpful messages to the stderr of nmcli, making
tests fail. For example:
=================================================================
==17156==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 256 byte(s) in 2 object(s) allocated from:
#0 0x7f08c7e27c88 in realloc (/lib64/libasan.so.5+0xefc88)
#1 0x7f08c7546e7d in g_realloc (/lib64/libglib-2.0.so.0+0x54e7d)
We already have code that parses exactly this kinds of string:
nm_utils_parse_inaddr_prefix_bin(). Use it.
Also, it doesn't use g_strsplit_set() to separate a string at the first
'/'. Total overkill.
- use cleanup macros everywhere.
- In particular use nm_auto_clear_variant_builder to free the
GVariantBuilder in the error cases. Note that the error cases
anyway are asserted against, so during a normal test run there
was no leak. But we should not write software like that.
- use nm_utils_strsplit_set_with_empty() instead of g_strsplit_set().
We should use our variant also in unit-tests, because that way the
function gets more test coverage. And it likely performs better
anyway.
Currently, if user configuration or settings specify that a software
device is unmanaged, for example:
[device-bond-unmanaged]
match-device=interface-name:bond*
managed=0
or
[keyfile]
unmanaged-devices=interface-name:bond*
and there is a connection for the device with autoconnect=yes, NM
creates the platform link and a realized device in unmanaged
state. Fix this, the device should not be realized if it is unmanaged.
https://bugzilla.redhat.com/show_bug.cgi?id=1679230
nm_device_spec_match_list_full() calls
nm_device_get_permanent_hw_address() which freezes the MAC address, so
currently callers must avoid the function when the device is not
completely platform-initialized.
Instead, use nm_device_get_permanent_hw_address_full() to avoid
freezing the MAC when the device is not platform-initialized. In this
way nm_device_spec_match_list_full() can be called from any state
without side effects.
Instead of growing the buffer for the tokens (and reallocating),
do one pre-run over the string and count the delimiters. This
way we know how much space we need and we don't need to
reallocate.
Interestingly, this is notably slower than the previous implementation,
because previously if would not bother determining the right number of
tokens but just over-allocate with a reasonable guess of 8 and grow the
buffer exponentially. Still, I like this better because while it may
be slower in common scenarios, it allocates the exact number of buffer
space.
- use nm_utils_strsplit_set_full() instead of g_strsplit_set() to avoid allocating
a full strv array.
- refactor the code to return early and use cleanup attribute for freeing
memory.
- return TRUE/FALSE from process_dhclient_rfc3442_route(). It's simpler to
understand than returning the moved pointer and a success output variable.
Previously, nm_utils_strsplit_set_full() would always remove empty
tokens. Add a flag NM_UTILS_STRSPLIT_SET_FLAGS_PRESERVE_EMPTY to avoid
that.
This makes nm_utils_strsplit_set_full() return the same result as
g_strsplit_set() and a direct replacement for it -- except for "",
where we return %NULL.
