* [client] Add catch-all NRPT rule when NetBird is the primary DNS resolver
* Remove obvious comments
* Install the catch-all rule where the adapter's DNS is set
addDNSSetupForAll makes us the peer's main DNS forwarder, and the catch-all NRPT
rule is the other half of that same job: without it the adapter's NameServer only
adds one more resolver to the set Windows queries in parallel. Having the two in
one place says that, where a separate block at the end of applyDNSConfig read as
an afterthought.
The block could not simply move up: removeDNSMatchPolicies deletes the catch-all
key too, so installing the rule before it ran would have had the rule deleted
moments later. The cleanup now runs first, which is what it was always for - it
clears what the previous apply installed before this one installs anything - and
keeps being unconditional, so a leftover rule from an earlier run cannot survive
into a config that no longer wants it.
* Name the escape hatch after the behaviour it restores
NB_DISABLE_DNS_CATCHALL_NRPT described the mechanism it switches off. What an
operator reaching for it wants is the behaviour they had before, so name it that:
NB_USE_LEGACY_DNS_RESOLUTION, matching NB_USE_LEGACY_ROUTING, the only other
legacy switch in the client.
Not NB_WIN_LEGACY_FULL_TUNNEL_DNS_RESOLVE, as first suggested: the rule follows a
primary nameserver group, not a full tunnel, and putting FULL_TUNNEL in a public
variable name would carry that confusion for as long as the variable lives. No
OS prefix either, since nothing else in the client has one and this switch is
inert anywhere but Windows by construction.
Behaviour and default are unchanged: the catch-all rule is on unless the variable
says otherwise.
* Exempt .local from the catch-all rule
RFC 6762 reserves .local for multicast DNS and says unicast resolvers must not
answer for it. The catch-all rule hands it to us anyway, we forward it to
whatever upstream the primary nameserver group points at, and the answer comes
back NXDOMAIN for hosts that do exist - printers, NAS boxes, anything
announcing itself on the link. Confirmed on a Win11Pro VM: laptop.local resolves
with the client down and returns "Nome DNS inesistente" with it up, and the
client log shows the query arriving on the catch-all handler and being forwarded
to 1.1.1.1.
An NRPT rule that names a namespace and lists no servers is an exemption: the
DNS client resolves those names as it would with no rule at all. What that looks
like in the registry is not what it sounds like. Writing no server value and
clearing ConfigOptions produces a rule Windows treats as a no-op - it never
appears in Get-DnsClientNrptPolicy -Effective and the catch-all keeps the query.
The value has to be present and empty, with ConfigOptions still 0x8: the flag
says the server list is the meaningful part of the rule, and an empty list then
means "no server, resolve normally". Verified both encodings on the VM.
Installed together with the catch-all, since without one nothing captures .local
in the first place, and removed with it.
Exclusivity is unaffected elsewhere, and a more specific rule still wins - a
match domain under .local keeps resolving through NetBird, which is what a
legacy Active Directory domain named corp.local needs. Verified separately that
a match domain does take precedence over the catch-all: declaring fritz.box
against the local router restored laptop.fritz.box while the catch-all was in
force.
* Treat the root namespace as a match domain, not a special case
The catch-all had a function, a registry key and a call site of its own, which
made it look like a different mechanism. It is not: "." is an NRPT namespace like
any other, it just happens to match every name. So it goes into the match domain
list, and addDNSMatchPolicy writes it along with the rest — batching, GPO
variant, volatile keys and cleanup all come for free.
The .local exemption stays a rule of its own, and not for symmetry: it is the one
rule with a different server list, an empty one. Putting it in the same Name
value would give it our resolver and exempt nothing.
Windows expands a rule's Name value into one effective namespace each, so a rule
carrying {.example.com, .} still shows both as separate rows in
Get-DnsClientNrptPolicy -Effective. Nothing is lost for diagnosis by dropping the
dedicated key.
Suggested by Vik in review.
* Do not report a failed NRPT cleanup as success
removeRegistryKeyFromDNSPolicyConfig returned nil for every OpenKey error, so a
permission or registry failure was indistinguishable from a key that was never
there. Cleanup then reported success while the rule stayed in force — which is
how a rule outlives the interface it points at and keeps sending every query to
an address that no longer answers.
Distinguish the two, the way listNRPTRuleKeys already does for the policy store
root: a missing key is nothing to do, anything else reaches the caller.
restoreHostDNS now propagates that error instead of logging it. applyDNSConfig
keeps logging on purpose: there we are about to write fresh rules over whatever
survived, while restore is the path where a rule left behind is the whole
problem.
Also addresses review nits on the tests: doc comments on the two added cases,
reported Close and DeleteKey errors so a failed cleanup cannot contaminate the
next registry test, and a context message on the exemption's namespace assertion.
* Optimize Windows DNS performance with domain batching and batch mode
Implement two-layer optimization to reduce Windows NRPT registry operations:
1. Domain Batching (host_windows.go):
- Batch domains per NRPT
- Reduces NRPT rules by ~97% (e.g., 184 domains: 184 rules → 4 rules)
- Modified addDNSMatchPolicy() to create batched NRPT entries
- Added comprehensive tests in host_windows_test.go
2. Batch Mode (server.go):
- Added BeginBatch/EndBatch methods to defer DNS updates
- Modified RegisterHandler/DeregisterHandler to skip applyHostConfig in batch mode
- Protected all applyHostConfig() calls with batch mode checks
- Updated route manager to wrap route operations with batch calls
* Update tests
* Fix log line
* Fix NRPT rule index to ensure cleanup covers partially created rules
* Ensure NRPT entry count updates even on errors to improve cleanup reliability
* Switch DNS batch mode logging from Info to Debug level
* Fix batch mode to not suppress critical DNS config updates
Batch mode should only defer applyHostConfig() for RegisterHandler/
DeregisterHandler operations. Management updates and upstream nameserver
failures (deactivate/reactivate callbacks) need immediate DNS config
updates regardless of batch mode to ensure timely failover.
Without this fix, if a nameserver goes down during a route update,
the system DNS config won't be updated until EndBatch(), potentially
delaying failover by several seconds.
Or if you prefer a shorter version:
Fix batch mode to allow immediate DNS updates for critical paths
Batch mode now only affects RegisterHandler/DeregisterHandler.
Management updates and nameserver failures always trigger immediate
DNS config updates to ensure timely failover.
* Add DNS batch cancellation to rollback partial changes on errors
Introduces CancelBatch() method to the DNS server interface to handle error
scenarios during batch operations. When route updates fail partway through, the DNS
server can now discard accumulated changes instead of applying partial state. This
prevents leaving the DNS configuration in an inconsistent state when route manager
operations encounter errors.
The changes add error-aware batch handling to prevent partial DNS configuration
updates when route operations fail, which improves system reliability.
* starting engine by passing file descriptor on engine start
* inject logger that does not compile
* logger and first client
* first working connection
* support for routes and working connection
* small refactor for better code quality in swift
* trying to add DNS
* fix
* updated
* fix route deletion
* trying to bind the DNS resolver dialer to an interface
* use dns.Client.Exchange
* fix metadata send on startup
* switching between client to query upstream
* fix panic on no dns response
* fix after merge changes
* add engine ready listener
* replace engine listener with connection listener
* disable relay connection for iOS until proxy is refactored into bind
* Extract private upstream for iOS and fix function headers for other OS
* Update mock Server
* Fix dns server and upstream tests
* Fix engine null pointer with mobile dependencies for other OS
* Revert back to disabling upstream on no response
* Fix some of the remarks from the linter
* Fix linter
* re-arrange duration calculation
* revert exported HostDNSConfig
* remove unused engine listener
* remove development logs
* refactor dns code and interface name propagation
* clean dns server test
* disable upstream deactivation for iOS
* remove files after merge
* fix dns server darwin
* fix server mock
* fix build flags
* move service listen back to initialize
* add wgInterface to hostManager initialization on android
* fix typo and remove unused function
* extract upstream exchange for ios and rest
* remove todo
* separate upstream logic to ios file
* Fix upstream test
* use interface and embedded struct for upstream
* set properly upstream client
* remove placeholder
* remove ios specific attributes
* fix upstream test
* merge ipc parser and wg configurer for mobile
* fix build annotation
* use json for DNS settings handover through gomobile
* add logs for DNS json string
* bring back check on ios for private upstream
* remove wrong (and unused) line
* fix wrongly updated comments on DNSSetting export
---------
Co-authored-by: Maycon Santos <mlsmaycon@gmail.com>
Supporting search domains will allow users to define match domains to also
be added to a list of search domains in their systems
Fix Windows registry key configuration for search domains using a key within the netbird interface path
* Add DNS list argument for mobile client
* Write testable code
Many places are checked the wgInterface != nil condition.
It is doing it just because to avoid the real wgInterface creation for tests.
Instead of this involve a wgInterface interface what is moc-able.
* Refactor the DNS server internal code structure
With the fake resolver has been involved several
if-else statement and generated some unused
variables to distinguish the listener and fake
resolver solutions at running time. With this
commit the fake resolver and listener based
solution has been moved into two separated
structure. Name of this layer is the 'service'.
With this modification the unit test looks
simpler and open the option to add new logic for
the permanent DNS service usage for mobile
systems.
* Remove is running check in test
We can not ensure the state well so remove this
check. The test will fail if the server is not
running well.
* Disable upstream DNS resolver after several tries and fails
* Add tests for upstream fails
* Use an extra flag to disable domains in DNS upstreams
* Fix hashing IPs of nameservers for updates.
Added host configurators for Linux, Windows, and macOS.
The host configurator will update the peer system configuration
directing DNS queries according to its capabilities.
Some Linux distributions don't support split (match) DNS or custom ports,
and that will be reported to our management system in another PR
Riccardo Manfrin