Motivation:
TCP Fast Open allows data to be carried in the SYN and SYN-ACK packets and consumed by the receiving end during the initial connection handshake, and saves up to one full round-trip time (RTT) compared to the standard TCP, which requires a three-way handshake (3WHS) to complete before data can be exchanged. This commit enables support for TFO on server sockets.
Modifications:
Added new Integer Option TCP_FASTOPEN in EpollChannelOption.
Added getters/setters in EpollServerChannelConfig for TCP_FASTOPEN.
Added way to check if TCP_FASTOPEN is supported on server in Native.
Added setting on socket opt TCP_FASTOPEN if value is set on channel options in doBind in EpollServerSocketChannel.
Enhanced EpollSocketTestPermutation to contain a permutation for server socket containing fast open.
Result:
Users of native-epoll can set TCP_FASTOPEN on server sockets and thus leverage fast connect features of RFC7413 if client is capable of it.
Motivation:
Invoking the javax.net.ssl.SSLEngine.closeInbound() method will send a
fatal alert and invalidate the SSL session if a close_notify alert has
not been received.
From the javadoc:
If the application initiated the closing process by calling
closeOutbound(), under some circumstances it is not required that the
initiator wait for the peer's corresponding close message. (See section
7.2.1 of the TLS specification (RFC 2246) for more information on
waiting for closure alerts.) In such cases, this method need not be
called.
Always invoking the closeInbound() method without regard to whether or
not the closeOutbound() method has been invoked could lead to
invalidating perfectly valid SSL sessions.
Modifications:
Added an instance variable to track whether the
SSLEngine.closeOutbound() method has been invoked. When the instance
variable is true, the SSLEngine.closeInbound() method doesn't need to be
invoked.
Result:
SSL sessions will not be invalidated if the outbound side has been
closed but a close_notify alert hasn't been received.
Motivation:
There are protocols (BGP, SXP), which are typically deployed with TCP
MD5 authentication to protect sessions from being hijacked/torn down by
third parties. This facility is not available on most operating systems,
but is typically present on Linux.
Modifications:
- add a new EpollChannelOption, which is write-only
- teach Epoll(Server)SocketChannel to track which addresses have keys
associated
- teach Native how to set the MD5 signature keys for a socket
Result:
Users of the native-epoll transport can set MD5 signature keys and thus
leverage RFC-2385 protection on TCP connections.
Motivation:
If LocalChannel doWrite executes while the peer's state changes from CONNECTED to CLOSED it is possible that some promise's won't be completed and buffers will be leaked.
Modifications:
- Check the peer's state in doWrite to avoid a race condition
Result:
All write operations should release, and the associated promise should be completed.
Motivation:
The configurable property value recently added was not logged like others properties.
Modifications:
Added debug log with effective value applied.
Result:
Consistent with other properties
Motivation:
See #4174.
Modifications:
Modify transport-native-epoll to allow setting TCP_USER_TIMEOUT.
Result:
Hanging connections that are written into will get timeouted.
Motivation:
Leak detector, when it detects a leak, will print the last 5 stack
traces that touched the ByteBuf. In some cases that might not be enough
to identify the root cause of the leak.
Also, sometimes users might not be interested in tracing all the
operations on the buffer, but just the ones that are affecting the
reference count.
Modifications:
Added command line properties to override default values:
* Allow to configure max number of stack traces to collect
* Allow to only record retain/release operation on buffers
Result:
Users can increase the number of stack traces to debug buffer leaks
with lot of retain/release operations.
Motivation:
As all methods in the ChannelHandler are executed by the same thread there is no need to use synchronized.
Modifications:
Remove synchronized keyword.
Result:
No more unnessary synchronized in SpdySessionHandler.
Motivation:
In NIO and OIO we throw a ChannelException if a ChannelConfig operation fails. We should do the same with epoll to be consistent.
Modifications:
Use ChannelException
Result:
Consistent behaviour across different transport implementations.
Motivation:
https://github.com/netty/netty/pull/4143 addressed a few ordering issues but an ordering issue still remained if the Promise for a write completes, and a listener of that promise does a write on a peer channel. The ordering was subject to how potentially 2 different executors would run a task, but it should be coordinated such that the first write is read first.
Modifications:
- Keep track of the finishPeerRead task run on the executor if necessary and ensure it completes before current channel read occurs
Result:
Ordering of events for echo type situations is preserved.
Motivation:
When a LocalChannel write operation occurs, the promise associated with the write operation is marked successful when it is added to the peer's queue, but before the peer has actually received the data. If the promise callback closes the channel then a race condition exists where the close event may occur before the data is delivered. We should preserve ordering of events.
Modifications:
- LocalChannel should track when a write is in progress, and if a close operation happens make sure the peer gets all pending read operations.
Result:
LocalChannel preserves order of operations.
Fixes https://github.com/netty/netty/issues/4118
Motivation:
The alpn / npn dependency versions are dependent on java version. If a java version 1.8+ is used that is not explicitly listed in the pom file then ALPN tests will fail because the java 1.7 version of alpn will be loaded by out pom file.
Modifications:
- Ensure there is a latest version to fall back up for npn 1.7+
- Ensure there is a latest version to fall back upon from alpn 1.8+
Result:
Build can complete despite having a newer jdk which is not listed in our pom file.
Motivation:
for debugging and metrics reasons its sometimes useful to be able to get details of the the Thread that powers a SingleThreadEventExecutor.
Modifications:
- Expose ThreadProperties
- Add unit test.
Result:
It's now possible to get details of the Thread that powers a SingleThreadEventExecutor.
Motivation:
Sometimes it is useful to disable recycling completely if memory constraints are very tight.
Modifications:
Allow to use -Dio.netty.recycler.maxCapacity.default=0 to disable recycling completely.
Result:
It's possible to disable recycling now.
Motivation:
When try to get SO_LINGER from a fd that is closed an Exception is thrown. We should only try to get SO_LINGER if the fd is still open otherwise an Exception is thrown that can be ignored anyway.
Modifications:
First check if the fd is still open before try to obtain SO_LINGER setting when get the closeExecutor. This is also the same that we do in the NIO transport.
Result:
No more exception when calling unsafe.close() on a channel that has a closed file descriptor.
Motivation:
OioSctpChannel.doReadMessages is iterating over the selected keys, and ignoring each selected key. It is not known why this is needed and no other channel implementation does this.
Modifications:
- Stop iterating over selected keys, and just read like other channels
Result:
No unnecessary iteration in OioSctpChannel.doReadMessages.
Fixes https://github.com/netty/netty/issues/3884
Motivation:
Doc of ChannelGroup says, that it can be used to manage server and child channels at once.
However, in DefaultChannelGroup, there is a race condition. When a server channel accepts a child, it schedules its
registration on an event loop, which takes some time. If the ChannelGroup, which is supposed
to close server and child channels at once, is closed after the child channel has been scheduled
for registration and before this registration actually happens, this child channel is not closed
and remains connected. This could lead to connection leaks.
Modifications:
To fix this, the DefaultChannelGroup is changed to has a closed flag.
This flag is set to true, just before the close() method is actually closing channels.
The add() method checks after adding a new channel, if this flag has been set to true.
If yes, the new channel is closed. If not, we have the guarantee, that this channel will be
closed by the ChannelGroup, because setting the closed flag to true happens-before closing any channels.
This behaviour can be activated by two new constructors. The old constructors are still there and behave like before.
Therefore, no existing code should be affected directly.
Result:
If activating this feature, the DefaultChannelGroup can be used, for managing server and child channels at once.
But this activating this feature means also, that a ChannelGroup cannot be reused after calling close().
Motivation:
The javadocs are incorrect and so give false impressions of use-pattern.
Modifications:
- Fix javadocs of which operations are allowed from multiple threads concurrently.
- Let isEmpty() work concurrently.
Result:
Correctly document usage-patterns.
Motivation:
The method implementions for setSoLinger(...) and setTrafficClass(...) were swapped by mistake.
Modifications:
Use the correct implementation for setSoLinger(...) and setTrafficClass(...)
Result:
Correct behaviour when setSoLinger(...) and setTrafficClass(...) are used with the epoll transport.
Motivation:
Currently the "derived" buffer will only ever be recycled if the release call is made on the "derived" object, and the "wrapped" buffer ends up being "fully released" (aka refcount goes to 0). From my experience this is not the common use case and thus the "derived" buffers will not be recycled.
Modifications:
- revert https://github.com/netty/netty/pull/3788
Result:
Less complexity, and less code to create new objects in majority of cases.
Motivation:
We missed to correctly implement the handlerRemoved(...) / channelInactive(...) and channelReadComplete(...) method, this leaded to multiple problems:
- Missed to forward bytes when the codec is removed from the pipeline
- Missed to call decodeLast(...) once the Channel goes in active
- No correct handling of channelReadComplete that could lead to grow of cumulation buffer.
Modifications:
- Correctly implement methods and forward to the internal ByteToMessageDecoder
- Add unit test.
Result:
Correct behaviour
Motivation:
The ipfilter handler does not exists in 4.0 yet.
Modifications:
Backport the ipfilter from 4.1 to 4.0.
Result:
It's possible to use the ipfilter handler in 4.0 as well.
Motivation:
Whe a 100 Continue response was written an IllegalStateException was produced as soon as the user wrote the following response. This regression was introduced by 41b0080fcc.
Modifications:
- Special handle 100 Continue responses
- Added unit tests
Result:
Fixed regression.
Motivation:
Hixie 76 needs special handling compared to other connection upgrade responses. Our detection code of non websocket responses did actually always use the special handling that only should be used for Hixie 76 responses.
Modifications:
Correctly detect connection upgrade responses which are not for websockets.
Result:
Be able to upgrade connections for other protocols then websockets.
Related: #3886
Motivation:
We were including OSGi manifests in sources/javadoc JARs, and OSGi
container treats them as correct dependencies when resolving from OBR
repository, which is incorrect. Runtime fails with non-descriptive
ClassNotFoundException as a result.
Modifications:
- Do not include the OSGi manifests in sources/javadoc JARs
- Include Eclipse-related manifest entries in sources/javadoc JARs
Result:
Better OSGi compatibility
Motivation:
The HTTP specification defines specific request-targets in https://tools.ietf.org/html/rfc7230#section-5.3. Netty does not have a way to distinguish between these differnt types, and there is currently no obvious location where these types of methods would live.
Modifications:
- Add methods to distinguish request-targets as defined in https://tools.ietf.org/html/rfc7230#section-5.3
Result:
Common utitlity methods exist to inpsect request-targets.
Motivation:
The StringUtil class creates a Formatter object, but does not close it. There are also a 2 utility methods which would be generally useful.
Modifications:
- Close the Formatter
- Add length and isNullOrEmpty
Result:
No more resource leaks. Additional utility methods.
Motivation:
On Android devices with version less than Lollipop, HarmonyJSSE is used for SSL. After completion of handshake, handshake status is NOT_HANDSHAKING instead of FINISHED. Also encrypting empty buffer after handshake should cause underflow exception and produce 0 bytes, but here it happily encrypts it causing for loop to never break
Modification:
Since 0 bytes should only be consumed in handshake process. Added a condition to break loop when 0 bytes are consumed and handshake status is NOT_HANDSHAKING
Result:
Sucessful ssl handshake on Android devices, no infinite loop now
Motivation:
When releasing unhealthy channel back to a pool we don't have to offer it since on acquire it will be discarded anyways.
Also checking healthiness at release is a good idea so we don't end up having tons of unhealthy channels in the pool(unless they became unhealthy after being offered)
Modifications:
private SimpleChannelPool.offerIfHealthy() method added that is called from SimpleChannelPool.doReleaseChannel(). SimpleChannelPool.offerIfHealthy() offers channel back to pool only if channel is healthy.
Otherwise it throws setFailure exception to the promise.
Result:
The pool is now much cleaner and not spammed with unhealthy channels.
Added ability to choose if channel health has to be validated on release by passing boolean flag.
Motivation:
Depending on performance preferences and individual use cases sometimes we would like to be able force health check of a channel at release time and do not offer it back to the pool. Other times we would want to just release channel and offer it back to the pool and check health only when we try to acquire that channel from the pool. See more details here: https://github.com/netty/netty/issues/4077#issuecomment-130461684
Modifications:
Future<Void> release(Channel channel, Promise<Void> promise, boolean offerHealthyOnly);
The offerHealthyOnly boolean flag allows developers to choose whether to do channel validation before offering it back to pool or not.
Appropriate modifications made to hierarchy of implementations of ChannelPool. offerHealthyOnly=true will force channel health to be checked before offering back to pool. offerHealthyOnly=false will ignore channel health check and will just try just offer it back to the pool
offerHealthyOnly=true by default.
Result:
Channel health check before offer back to pool is controlled by a flag now.
Code changed to satisfy checkstyle requirements.
Motivation:
Code needs to satisfy checkstyle requirements.
Modifications:
SimpleChannelPool.java:279 line split to be less then 120 characters.
SimpleChannelPool.java:280:31 space added after '{'
SimpleChannelPool.java:282:17 space added after '{'
SimpleChannelPoolTest.java:198 - extra white space line removed.
Result:
Code satisfies checkstyle requirements.
offerHealthyOnly is passed as a constructor parameter now.
Motivation:
Instead of passing offerHealthyOnly as a method parameter it is better to pass it in as SimpleChannelPool or FixedChannelPool constructor.
Modifications:
Redundant release method that takes offerHealthyOnly removed from ChannelPool.
offerHealthyOnly parameter added to constructor for FixedChannelPool and SimpleChannelPool.
Result:
SimpleChannelPool and FixedChannelPool are now take offerHealthyOnly as a constructor parameter. Default behavior is: offerHealthyOnly=true.
Code changed to satisfy checkstyle requirements.
Motivation:
Code needs to satisfy checkstyle requirements.
Modifications:
SimpleChannelPool.java:84: line made to be no longer then 120 characters.
SimpleChannelPool.java:237: extra white space line removed.
Result:
Code satisfies checkstyle requirements.
Tests do not need to be too copled to the code. Exception message should not be validated
Motivation:
We don't need our tests to be too coupled to the code. Exception type validation in tests is just good enough.
Modifications:
Exception validation message removed from SimpleChannelPoolTest.testUnhealthyChannelIsNotOffered() test.
Result:
The SimpleChannelPoolTest test is less coupled to the code now.
Stack trace set to empty for UNHEALTHY_NON_OFFERED_TO_POOL.
Motivation:
We don't need stack trace for UNHEALTHY_NON_OFFERED_TO_POOL.
Modifications:
Added UNHEALTHY_NON_OFFERED_TO_POOL.setStackTrace(EmptyArrays.EMPTY_STACK_TRACE) to static init block.
Result:
UNHEALTHY_NON_OFFERED_TO_POOL's stack trace set to empty.
Minor code re-factorings.
Motivation:
For better code readability we need to apply several minor code re-factorings.
Modifications:
javadocs true -> {@code true}
offerHealthyOnly variable name changed to releaseHeathCheck
<p/> -> <p> in javadocs
offerHealthyOnly removed from doReleaseChannel as it not needed there.
Result:
Code quality is improved.
Code changed to satisfy checkstyle requirements.
Motivation:
Code needs to satisfy checkstyle requirements.
Modifications:
SimpleChannelPool.java:87: line made to be no longer then 120 characters.
Result:
Code satisfies checkstyle requirements.
Pull request needs to contain only necessary changes
Motivation:
The pull request should not contain unnecessary changes that are not needed as part of required functionality of pull request.
Modifications:
private void doReleaseChannel(final Channel channel, final Promise<Void> promise) - > private void doReleaseChannel(Channel channel, Promise<Void> promise)
Result:
Pull request contains less unnecessary modifications.
Motivation:
Because of java custom UTF encoding, it was previously impossible to use
nul-bytes in domain socket names, which is required for abstract domain
sockets.
Modifications:
- Pass the encoded string byte array to the native code
- Modify native code accordingly to work with nul-bytes in the the
array.
- Move the string encoding to UTF-8 in java code.
Result:
Unix domain socket addresses will work properly if they contain nul-
bytes. Address encoding for these addresses changes from UTF-8-like to
real UTF-8.
Motivation:
Due not using a cast we insert 32 and not a whitespace into the String.
Modifications:
Correclty cast to char.
Result:
Correct handling of whitespaces.
Motivation:
The HttpObjectAggregator always responds with a 100-continue response. It should check the Content-Length header to see if the content length is OK, and if not responds with a 417.
Modifications:
- HttpObjectAggregator checks the Content-Length header in the case of a 100-continue.
Result:
HttpObjectAggregator responds with 417 if content is known to be too big.
Motivation:
If is enabled and a channel is half closed it is possible for the EPOLL event loop to get into an infinite loop by continuously being woken up on the EPOLLRDHUP event.
Modifications:
- Ensure that the EPOLLRDHUP event is unregistered for to prevent infinite loop.
Result:
1 less infinite loop.
Motivation:
New versions of alpn-boot and npn-boot have been released.
Modifications:
- Update pom to pull in new versions.
Result:
Dependencies more up to date.
Motivation:
We not set any optimization flag when compile native transport
Modification:
Add -O3 to CFLAGS to have GCC do optimizations
Result:
Ship optimized native code
Motivation:
Sometimes the user already has a PrivateKey / X509Certificate which should be used to create a new SslContext. At the moment we only allow to construct it via Files.
Modifications:
- Add new methods to the SslContextBuilder to allow creating a SslContext from PrivateKey / X509Certificate
- Mark all public constructors of *SslContext as @Deprecated, the user should use SslContextBuilder
- Update tests to us SslContextBuilder.
Result:
Creating of SslContext is possible with PrivateKay/X509Certificate
