* fix(rewrite): fix cname target rewrite for CNAME chains
This fix corrects the cname target rewrite to handle CNAME chains:
- Preserves only the CNAME records before matching the rule
- Rewrites only the CNAME target that matches the rule
- Includes all records from the re-resolved upstream response
Signed-off-by: hide <hide@hide.net.eu.org>
* docs(rewrite): document how answer records are handled in CNAME target rewrite
Signed-off-by: hide <hide@hide.net.eu.org>
* fix(rewrite): simplify slice append per staticcheck S1011
Signed-off-by: hide <hide@hide.net.eu.org>
* docs(rewrite): add extra line between code and paragraph
Signed-off-by: hide <hide@hide.net.eu.org>
---------
Signed-off-by: hide <hide@hide.net.eu.org>
Co-authored-by: hide <hide@hide.net.eu.org>
* fix: return SOA and NS records when queried for a record CNAMEd to origin
Signed-off-by: Shiv Tyagi <shivtyagi3015@gmail.com>
* chore(test): add test for covering cname to origin scenario in file plugin
Signed-off-by: Shiv Tyagi <shivtyagi3015@gmail.com>
---------
Signed-off-by: Shiv Tyagi <shivtyagi3015@gmail.com>
* perf(proxy): use mutex-based connection pool
The proxy package (used for example by the forward plugin) utilized
an actor model where a single connManager goroutine managed
connection pooling via unbuffered channels (dial, yield, ret). This
design serialized all connection acquisition and release operations
through a single goroutine, creating a bottleneck under high
concurrency. This was observable as a performance degradation when
using a single upstream backend compared to multiple backends
(which sharded the bottleneck).
Changes:
- Removed dial, yield, and ret channels from the Transport struct.
- Removed the connManager goroutine's request processing loop.
- Implemented Dial() and Yield() using a sync.Mutex to protect the
connection slice, allowing for fast concurrent access without
context switching.
- Downgraded connManager to a simple background cleanup loop that
only handles connection expiration on a ticker.
- Updated plugin/pkg/proxy/connect.go to use direct method calls
instead of channel sends.
- Updated tests to reflect the removal of internal channels.
Benchmarks show that this change eliminates the single-backend
bottleneck. Now a single upstream backend performs on par with
multiple backends, and overall throughput is improved.
The implementation aligns with standard Go patterns for connection
pooling (e.g., net/http.Transport).
Signed-off-by: Ville Vesilehto <ville@vesilehto.fi>
* fix: address PR review for persistent.go
- Named mutex field instead of embedding, to not expose
Lock() and Unlock()
- Move stop check outside of lock in Yield()
- Close() without a separate goroutine
- Change stop channel to struct
Signed-off-by: Ville Vesilehto <ville@vesilehto.fi>
* fix: address code review feedback for conn pool
- Switch from LIFO to FIFO connection selection for source port
diversity, reducing DNS cache poisoning risk (RFC 5452).
- Remove "clear entire cache" optimization as it was LIFO-specific.
FIFO naturally iterates and skips expired connections.
- Remove all goroutines for closing connections; collect connections
while holding lock, close synchronously after releasing lock.
Signed-off-by: Ville Vesilehto <ville@vesilehto.fi>
* fix: remove unused error consts
No longer utilised after refactoring the channel based approach.
Signed-off-by: Ville Vesilehto <ville@vesilehto.fi>
* feat(forward): add max_idle_conns option
Add configurable connection pool limit for the forward plugin via
the max_idle_conns Corefile option.
Changes:
- Add SetMaxIdleConns to proxy
- Add maxIdleConns field to Forward struct
- Add max_idle_conns parsing in forward plugin setup
- Apply setting to each proxy during configuration
- Update forward plugin README with new option
By default the value is 0 (unbounded). When set, excess
connections returned to the pool are closed immediately
rather than cached.
Also add a yield related test.
Signed-off-by: Ville Vesilehto <ville@vesilehto.fi>
* chore(proxy): simple Dial by closing conns inline
Remove toClose slice collection to reduce complexity. Instead close
expired connections directly while iterating. Reduces complexity with
negligible lock-time impact.
Signed-off-by: Ville Vesilehto <ville@vesilehto.fi>
* chore: fewer explicit Unlock calls
Cleaner and less chance of forgetting to unlock on new possible
code paths.
Signed-off-by: Ville Vesilehto <ville@vesilehto.fi>
---------
Signed-off-by: Ville Vesilehto <ville@vesilehto.fi>
