## Summary
This change lets the listener batch incoming UDP datagrams when
`--udp-recvmmsg` is enabled, reducing per-packet overhead on busy
listeners while preserving the existing behavior as the default and
fallback path.
## What changed
- add a new `--udp-recvmmsg` runtime flag
- implement a batched UDP receive path in the DTLS listener using
`recvmmsg()`
- reuse packet classification and datagram processing logic across
batched and non-batched receive paths
- reduce buffer/metadata churn by reusing listener-side scratch state
and network buffers
- keep compatibility safeguards by falling back when `recvmmsg()` is
unavailable or unsupported
- expose the setting in admin/CLI configuration output
- update the example test runner to enable the flag on Linux
## Why
The current listener processes UDP datagrams one at a time. On Linux,
`recvmmsg()` allows the server to receive multiple packets per syscall,
which should improve throughput and lower CPU overhead under load for
UDP-heavy traffic.
## Notes
- the feature is opt-in and defaults to disabled
- the implementation is Linux-specific and leaves the existing path
unchanged on other platforms
- the listener still falls back to the legacy receive path if batched
receive is unavailable at runtime
## Testing
- updated `examples/run_tests.sh` to pass `--udp-recvmmsg` on Linux
- validated behavior through the existing listener flow and fallback
handling
Remove the two engine implementations (NEV_UDP_SOCKET_PER_SESSION and
NEV_UDP_SOCKET_PER_ENDPOINT) and all the dispatch/selection logic around
them. NEV_UDP_SOCKET_PER_THREAD is now the sole, unconditional
implementation.
- mainrelay.h: removed _NET_ENG_VERSION enum, typedef, and
net_engine_version / net_engine_version_txt struct fields
- mainrelay.c: removed NE_TYPE_OPT CLI option, set_network_engine(),
per-endpoint branch in print_features(), and all remaining
net_engine_version references
- netengine.c: removed run_udp_listener_thread(),
setup_socket_per_endpoint_udp_listener_servers() (~190 lines),
setup_socket_per_session_udp_listener_servers() (~90 lines); simplified
setup_barriers(), setup_relay_server(), run_general_relay_thread(),
setup_general_relay_servers(), and setup_server() by eliminating all
engine-type conditionals
- turn_admin_server.c: replaced dynamic engine version lookups with
hardcoded values (3 / "UDP thread per CPU core") in CLI and HTTPS status
handlers
---------
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
Small fixes across CI workflows and test scripts:
- In examples/run_tests.sh & examples/run_tests_conf.sh: ensure both
turnserver and the turnutils_peer background process are killed at the
end
- cmake.yml so binaries end up in the expected folder
- linux.yml - add install so that binaries are in the expected folder
cli interface is ON by default which creates a security risk (even
though requires a password) and recommended to be disabled.
Instead of just recommendation, this PR disables CLI by default and now
requires an explicit flag to enable it
If using old configuration or cli arguments to turnserver - it will log
an error message about `--no-cli` being deprecated while doing nothing
(already disabled). This log line will be removed in the future
Disable the messages by default - they can be re-enabled using
`--include-reason-string` option
As a result of not sending reason string (which is optional by standard
and provide debugging information for the actual numeric error code)
response message size can be decreased by up to NNN bytes.
Some places in code do not have access to the buffer size which result
in crash which can be seen in tests
This PR removes the call to `set_ioa_socket_buf_size` from those places
(which is redundant anyway)
# Description
Replace the hardcoded buffer sizes inside coturn to make them
configurable for different use cases (low bitrate use cases can save
memory and high bitrate use case can avoid congestion) - based on #1089
Add this feature in both sides (listener and relay connections).
# Tests
For now it is only the automated CI tests.
Confirmed with debugger that buffer sizes are set according to the
arguments.
This PR adds a new `--cpus` configuration option to address CPU
detection issues in virtualized and containerized environments where
`_SC_NPROCESSORS_CONF` and `_SC_NPROCESSORS_ONLN` return host CPU counts
instead of allocated container CPUs.
## Problem
In containerized deployments, coturn detects the host's CPU count (e.g.,
128 CPUs) instead of the container's allocated CPUs (e.g., 2 CPUs). This
causes the server to create excessive relay threads and database
connections, leading to resource exhaustion and performance issues.
## Solution
Added a new `cpus` configuration option that allows manual override of
CPU detection:
### Command Line Usage
```bash
turnserver --cpus 2
```
### Configuration File Usage
```ini
# Override system CPU count detection for containers
cpus=2
```
## Key Features
- **Backward Compatible**: No changes needed for existing deployments
- **Input Validation**: Values must be between 1 and 128 with proper
error handling
- **Comprehensive Documentation**: Updated man pages and example config
files
- **Both Interfaces**: Works via command line and configuration file
## Testing
The implementation has been thoroughly tested:
```bash
# Container with 2 allocated CPUs on 128-CPU host
$ turnserver --cpus 2
INFO: System cpu num is 128 # Host detection
INFO: System enable num is 128 # Host detection
INFO: Configured cpu num is 2 # Override applied
INFO: Total General servers: 2 # Correct thread count
```
- ✅ Command line option: `--cpus 8` creates 8 relay servers
- ✅ Config file option: `cpus=6` creates 6 relay servers
- ✅ Error handling: Invalid values show appropriate errors
- ✅ Default behavior: Without option, uses system detection
- ✅ RFC5769 tests: All protocol tests still pass
## Files Modified
- `src/apps/relay/mainrelay.c` - Core implementation
- `src/apps/relay/mainrelay.h` - Added configuration flag
- `examples/etc/turnserver.conf` - Added documentation and example
- `man/man1/turnserver.1` - Updated man page
This change directly addresses the resource consumption issues in
containerized environments while maintaining full backward
compatibility.
Fixes#1628.
Set new release version to 4.7.0
Updating minor version due to some breaking changes in options to enable
more secure/robust configuration without additional flags (or relying on
recommended conf file which people seem to skip during updates)
TLSv1 and TLSv1.1 can be enabled using `--tlsv1` and `--tlsv1_1`
arguments accordingly
That assumes openssl version being used has these versions enabled
(which as of openssl-3.5 is not by default)
Deprecate `--no-stun-backward-compatibility` and set it to true by
default
Add new option `--stun-backward-compatibility`, off by default
Update example/recommended configuration files
This is a breaking change as passing `--no-stun-backward-compatibility`
will be rejected as invalid argument
Invert `--no-rfc5780` option to be true by default
Make it `--rfc5780` to enable it
Update example/recommended configuration files
Passing `--no-rfc5780` will have no effect as this is the default
behavior now
The `#allocation-default-address-family="ipv4"` line is repeated twice
in the example config, changed the second one to be `"ipv6"` which I
assume it was intended to be.
Add a `--prometheus-path` parameter which allows users to specify at
what
path the metrics should be exposed.
This simplifies serving metrics on a specific path behind some
restrictive reverse proxies that expect the upstream server to serve
URLs with paths matching the requested path.
Co-authored-by: Pavel Punsky <eakraly@users.noreply.github.com>
Some actions do not build with prometheus - adding prometheus tests
fails the jobs
cmake build tests did not run due to different target folder (while
reporting success) - now the bin folder is detected
Implement a custom prometheus http handler in order to:
1. Support listening on a specified address as opposed to any
2. Remove the requirement on the unmaintained promhttp library
This feature comes with one limitation: if an IPv4 address is used, the
server will not listen on the IPv6-mapped address, even if IPv6 is
available. That is, dual-stacking does not work.
Solves: #1475
---------
Co-authored-by: Pavel Punsky <eakraly@users.noreply.github.com>
I believe that many users, like myself, prefer to reference the
`turn.conf` file when deploying the TURN server with Docker, rather than
the `Readme.turnserver`. Additionally, I think it's important to
synchronize the Prometheus settings from the README into the` turn.conf`
file for better clarity. This way, users won't overlook any essential
options.
Co-authored-by: Ben Chang <ben_chang@htc.com>
Fixes#1533 and #1534
Memsetting `turn_params.default_users_db` before reading conf file, not
after.
Because auth is read in first iteration so secret was wiped out.
# test plan
Add new test script that uses config file to setup turnserver instead of
cli arguments and confirm it works (fails without the change)
For our deployment, it is useful if coturn returns a valid HTTP response to an HTTP request. To do this on the same port as STUN/TURN and without enabling the admin site, I have extended `read_client_connection()` to return a canned HTTP response, in response to an HTTP request, rather than immediately closing the connection.
Fixes https://github.com/coturn/coturn/issues/1239
https to web ui freeze in browser if no_tls option used, because no tls
stuff initialized.
This PR add warning about this and comment aboute this in default config
Similar to #989, use a single SSL context for all versions of DTLS
protocol
- Add support for modern API (protocol version independent APIs)
- Add DTLS test to the CI test
- Removing calls to `SSL_CTX_set_read_ahead` in DTLS context (does
nothing as DTLS is datagram protocol - we always get the whole datagram
so this call has no impact)
Fixes#924
openssl allows multiple TLS version support through a single SSL_CTX
object.
This PR replaces 4 per-version SSL_CTX objects with a single object
(DTLS is not yet changed).
SSL context initialization code for openssl with modern API (>=1.1.0)
uses `TLS_server_method` and `SSL_CTX_set_min_proto_version` instead of
enabling specific TLS version. Byproduct of this is TLSv1_3 support when
used with openssl-1.1.1 and above
TLS 1.2 and TLS 1.3 cannot be disabled (as before)
Test plan:
- run_tests.sh script now runs turnserver with SSL certificate (which
enables TLS support)
- run_tests.sh now has one more basic test that uses TLS protocol
Co-authored-by: Pavel Punsky <pavel.punsky@epicgames.com>
Pavel Punsky