Motivation:
Calling flush() and writeAndFlush(...) are expensive operations in the sense as both will produce a write(...) or writev(...) system call if there are any pending writes in the ChannelOutboundBuffer. Often we can consolidate multiple flush operations into one if currently a read loop is active for a Channel, as we can just flush when channelReadComplete is triggered. Consolidating flushes can give a huge performance win depending on how often is flush is called. The only "downside" may be a bit higher latency in the case of where only one flush is triggered by the user.
Modifications:
Add a FlushConsolidationHandler which will consolidate flushes and so improve the throughput.
Result:
Better performance (throughput). This is especially true for protocols that use some sort of PIPELINING.
Motivation:
ReadTimeoutHandler and IdleStateHandler have duplicated code, we should share whatever possible.
Modifications:
Let ReadTimeoutHandler extend IdleStateHandler.
Result:
Remove code duplication.
Motivation:
Unit test for the OpenSslEngine "OpenSslEngine writePlaintextData WANT_READ with no data in BIO buffer" issue.
Modifications:
- Update SslEngine test to include renegotiation
Result:
More test coverage in OpenSslEngine.
Motivation:
The gRPC interop tests fail due to a NPE in OpenSslEngine.
Caused by: java.lang.NullPointerException
at io.netty.handler.ssl.OpenSslEngine.setSSLParameters(OpenSslEngine.java:1473)
Modifications:
Add a null check
Result:
No more NPE exceptions :-)
Motivation:
To be able to use SslProvider.OpenSsl with existing java apps that use the JDK SSL API we need to also provide a way to use it with an existing KeyManagerFactory.
Modification:
Make use of new tcnative apis and so hook in KeyManagerFactory.
Result:
SslProvider.OpenSsl can be used with KeyManagerFactory as well.
Motivation:
Java8+ adds support set a DH key size via a System property (jdk.tls.ephemeralDHKeySize). We should respect this when using OpenSSL.
Modifications:
Respect system property.
Result:
More consistent SSL implementation.
Motivation:
We recently added support for session ticket statistics which we can expose now.
Modifications:
Expose the statistics.
Result:
Be able to obtain session ticket statistics.
Motivation:
We need to return a correct time for SSLSession.getLastAccessedTime() so it reflect when the handshake was done when the session was reused.
Modifications:
Correctly reflect handshake time in getLastAccessedTime().
Result:
More conform SSLSession implementation.
Motivation:
Sometimes its needed to customize the SSLEngine (like setting protocols etc). For this it would be useful if the user could wrap an SslContext and do init steps on the SSLEngine.
Modifications:
Add new SslContext implementation which can wrap another one and allow to customize the SSLEngine
Result:
More flexible usage of SslContext.
Motivation:
At the moment OpenSslEngine.getSupportedCipherSuites() only return the original openssl cipher names and not the java names. We need also include the java names.
Modifications:
Correctly return the java names as well.
Result:
Correct implementation of OpenSslEngine.getSupportedCipherSuites()
Motivation:
These methods were recently deprecated. However, they remained in use in several locations in Netty's codebase.
Modifications:
Netty's code will now access the bootstrap config to get the group or child group.
Result:
No impact on functionality.
Motivation:
There is no need already use synchronized when validate the args of the methods.
Modifications:
First validate arguments and then use synchronized
Result:
Less code executed in synchronized block.
Motivation:
We use pre-instantiated exceptions in various places for performance reasons. These exceptions don't include a stacktrace which makes it hard to know where the exception was thrown. This is especially true as we use the same exception type (for example ChannelClosedException) in different places. Setting some StackTraceElements will provide more context as to where these exceptions original and make debugging easier.
Modifications:
Set a generated StackTraceElement on these pre-instantiated exceptions which at least contains the origin class and method name. The filename and linenumber are specified as unkown (as stated in the javadocs of StackTraceElement).
Result:
Easier to find the origin of a pre-instantiated exception.
Motivation:
At the moment SSLSession.getId() may always return an empty byte array when OpenSSLEngine is used. This is as we not set SSL_OP_NO_TICKET on the SSLContext and so SSL_SESSION_get_id(...) will return an session id with length of 0 if tickets are not used.
Modifications:
- Set SSL_OP_NO_TICKET by default and only clear it if the user requests the usage of session tickets.
- Add unit test
Result:
Ensure consistent behavior between different SSLEngine implementations.
Motivation:
When using java8+ we should support SSLParameters.setCipherSuiteOrder()
Modifications:
Add support of SLParameters.setCipherSuiteOrder() by using reflection, so we can compile with java7 but still support it.
Result:
Users that use java8+ can use SSLParameters.setCipherSuiteOrder()
Motivation:
Java8 added support for using SNIHostName with SSLParameters. We currently ignore it in OpenSslEngine.
Modifications:
Use reflection to support SNIHostName.
Result:
People using Java8 can use SNIHostName even when OpenSslEngine is used.
Motivation:
We missed to skip some tests for OpenSsl when OpenSsl.isAvailable() is false.
Modifications:
- Correctly skip tests when OpenSsl.isAvailable() is false.
- Simplify some code by using @BeforeClass.
Result:
Be able to compile netty even when OpenSsl is not present on the system.
Motivation:
When the OpenSslContext is gc'ed and the user still hold a reference to OpenSslSessionContext / OpenSslSessionStats it is possible to produce a segfault when calling
a method on any of these that tries to pass down the ctx pointer to the native methods. This is because the OpenSslContext finalizer will free the native pointer.
Modifications:
Change OpenSslSessionContext / OpenSslSessionContext to store a reference to OpenSslContext and so prevent the GC to collect it as long as the user has a reference to OpenSslSessionContext / OpenSslSessionContext.
Result:
No more sefault possible.
Motivation
This bug was introduced with #5377 and affects only users who'd like to share/cache/re-use `PemPrivateKey` and `PemX509Certificate` instances.
Modifications
Use `ByteBuf#writeBytes(src, readerIndex, length)` so that the src's readerIndex doesn't change and can consequently be used more than once.
Result
It's possible to share/cache/re-use `PemPrivateKey` and `PemX509Certificate` instances as long as their refCnt remains >= 1.
Motivation:
2b65258568 only partially addressed the synchronization issues that are present in FlowControlHandlerTest. A few tests are attempting to validate state changes made across an EventLoop thread and the JUnit thread but are not properly synchronized.
Modifications:
- Ensure that conditions which verify expectations set in another thread have synchronization gates to ensure the event has actually occurred.
- Remove the message counter verification in favor of using individual CountDownLatch objects
Result:
FLowControlHanderTest has less race conditions which may lead to test failures.
Motivation
OpenSslContext is expecting Java's PrivateKey and X509Certificate objects as input
(for JdkSslContext API compatibility reasons) but doesn't really use them beyond
turning them into PEM/PKCS#8 strings.
This conversion can be entirely skipped if the user can pass in private keys and
certificates in a format that Netty's OpenSSL code can digest.
Modifications
Two new classes have been added that act as a wrapper around the pre-encoded byte[]
and also retain API compatibility to JdkSslContext.
Result
It's possible to pass PEM encoded bytes straight into OpenSSL without having to
parse them (e.g. File to Java's PrivateKey) and then encode them (i.e. PrivateKey
into PEM/PKCS#8).
File pemPrivateKeyFile;
byte[] pemBytes = readBytes(pemPrivateKeyFile);
PemPrivateKey pemPrivateKey = PemPrivateKey.valueOf(pemBytes);
SslContextBuilder.forServer(pemPrivateKey)
.sslProvider(SslProvider.OPENSSL)
Motivation:
JCTools supports both non-unsafe, unsafe versions of queues and JDK6 which allows us to shade the library in netty-common allowing it to stay "zero dependency".
Modifications:
- Remove copy paste JCTools code and shade the library (dependencies that are shaded should be removed from the <dependencies> section of the generated POM).
- Remove usage of OneTimeTask and remove it all together.
Result:
Less code to maintain and easier to update JCTools and less GC pressure as the queue implementation nt creates so much garbage
Motivation:
OpenSslClientContext / OpenSslServerContext can never be garbage collected as both are part of a reference to a callback that is stored as global reference in jni code.
Modifications:
Ensure the callbacks are static and so not hold the reference.
Result:
No more leak due not collectable OpenSslClientContext / OpenSslServerContext
Motivation:
OpenSslEngine.wrap will only encrypt at most 1 buffer per call. We may be able to encrypt multiple buffers per call.
Modifications:
- OpensslEngine.wrap should continue encrypting data until there is an error, no more data, or until the destination buffer would be overflowed.
Result:
More encryption is done per OpenSslEngine.wrap call
Motivation:
CVE-2016-4970
OpenSslEngine.wrap calls SSL_write which may return SSL_ERROR_WANT_READ, and if in this condition there is nothing to read from the BIO the OpenSslEngine and SslHandler will enter an infinite loop.
Modifications:
- Use the error code provided by OpenSSL and go back to the EventLoop selector to detect if the socket is closed
Result:
OpenSslEngine correctly handles the return codes from OpenSSL and does not enter an infinite loop.
Motivation:
OpenSslEngine calls rejectRemoteInitiatedRenegation in a scenario where the number of handshakes has not been observed to change. The number of handshakes has only been observed to change after readPlaintextData is called.
Modifications:
- Remove the call to rejectRemoteInitiatedRenegation before calls to readPlaintextData
Result:
Less code.
Motivation:
When netty is used with open ssl provider and client authentication the following errors can occur:
error:140D9115:SSL routines:ssl_get_prev_session:session id context uninitialized
error:140A1175:SSL routines:ssl_bytes_to_cipher_list:inappropriate fallback
error:140760FC:SSL routines:SSL23_GET_CLIENT_HELLO:unknown protocol
Modifications:
Set the session id context in OpenSslServerContext so that sessions which use client authentication
which are cached have the same context id value.
Result:
Client authentication now works with open ssl provider.
Motivation:
DomainMappingBuilder should have been named as DomainNameMappingBuilder
because it builds a DomainNameMapping.
Modifications:
- Add DomainNameMappingBuilder that does the same job with
DomainMappingBuilder
- Deprecate DomainMappingBuilder and delegate its logic to
DomainNameMappingBuilder
- Remove the references to the deprecated methods and classes related
with domain name mapping
- Miscellaneous:
- Fix Javadoc of DomainNameMapping.asMap()
- Pre-create the unmodifiable map in DomainNameMapping
Result:
- Consistent naming
- Less use of deprecated API
Related: #4333#4421#5128
Motivation:
slice(), duplicate() and readSlice() currently create a non-recyclable
derived buffer instance. Under heavy load, an application that creates a
lot of derived buffers can put the garbage collector under pressure.
Modifications:
- Add the following methods which creates a non-recyclable derived buffer
- retainedSlice()
- retainedDuplicate()
- readRetainedSlice()
- Add the new recyclable derived buffer implementations, which has its
own reference count value
- Add ByteBufHolder.retainedDuplicate()
- Add ByteBufHolder.replace(ByteBuf) so that..
- a user can replace the content of the holder in a consistent way
- copy/duplicate/retainedDuplicate() can delegate the holder
construction to replace(ByteBuf)
- Use retainedDuplicate() and retainedSlice() wherever possible
- Miscellaneous:
- Rename DuplicateByteBufTest to DuplicatedByteBufTest (missing 'D')
- Make ReplayingDecoderByteBuf.reject() return an exception instead of
throwing it so that its callers don't need to add dummy return
statement
Result:
Derived buffers are now recycled when created via retainedSlice() and
retainedDuplicate() and derived from a pooled buffer
Motivation:
Sometimes it is useful to include more details in the IdleStateEvents that are produced by the IdleStateHandler. For this users should be able to create their own IdleStateEvents that encapsulate more informations.
Modifications:
- Make IdleStateEvent constructor protected and the class non-final
- Add protected method to IdleStateHandler that users can override and so create their own IdleStateEvents.
Result:
More flexible and customizable IdleStateEvents / IdleStateHandler
Motivation:
We should zero-out the private key as soon as possible when we not need it anymore.
Modifications:
zero out the private key before release the buffer.
Result:
Limit the time the private key resist in memory.
Motivation:
FlowControlHandlerTest attempts to validate the expected contents of the underlying queue in FlowControlHandler. However the condition which triggers the check is too early and the queue contents may not yet contain all expected objects. For example a CountDownLatch is counted down in a handler's channelRead which is after the FlowControlHandler in the pipeline. At this point if there is a thread context switch the queue may not yet contain all the expected objects and checking the queue contents is not valid.
Modifications:
- Remove checking the queues contents in FLowControlHandlerTest and instead only check the empty condition at the end of the tests
Result:
FlowControlHandlerTest won't fail due to invalid checks of the contents of the queue.
Motivation:
The current note reads as if this class is dangerous and advises the reader to "understand what this class does".
Modifications:
Rewrite the Javadoc note to describe what fingerprint checks are and what problems remain.
Result:
Clearer description which no longer causes the impression this class is dangerous.
Motivations
The test SniHandlerTest#testSniWithApnHandler() does not actually
involve SNI: given the client setup, the ClientHello in the form of hex
strings is not actually written to the wire, so the server never receives that.
We may need to write in somewhere else (e.g., channelActive()) instead of in
initChannel() in order for the hex strings to reach the server. So here
what's actually going on is an ordinary TLS C/S communication without SNI.
Modifications
The client part is modified to enable SNI by using an SslHandler with an
SSLEngine created by io.netty.handler.ssl.SslContext#newEngine(), where
the server hostname is specified. Also, more clauses are added to verify that
the SNI is indeed successful.
Results
Now the test verifies that both SNI and APN actually happen and succeed.
Motivation:
Some handlers such as HttpObjectDecoder can emit more than one event per read()
which leads to problems in downstream handlers that expect only one event and hope
that ChannelConfig#setAutoRead(false) prevents further events being sent while they're
processing the one they've just received.
Modifications:
A new handler called FlowControlHandler that feeds off read() and isAutoRead() and acts
as a holding buffer if auto reading gets turned off and more events arrive while auto reading
is off.
Result:
Fixes issues such as #4895.
Motivation:
Some applications may use alternative methods of loading the tcnative JNI symbols. We should support this use case.
Modifications:
Separate the loading and initialzation of the tcnative library so that each can fail independently.
Result:
Fixes#5043
Motivation:
Sometimes a user only has access to a preconfigured SSLContext but still would like to use our ssl sub-system. For this situations it would be very useful if the user could create a JdkSslContext instance from an existing SSLContext.
Modifications:
- Create new public constructors in JdkSslContext which allow to wrap an existing SSLContext and make the class non-abstract
- Mark JdkSslServerContext and JdkSslClientContext as deprecated as the user should not directly use these.
Result:
It's now possible to create an JdkSslContext from an existing SSLContext.
Motivation:
fcbeebf6df introduced a unit test to verify ApplicationProtocolNegotiationHandler is compatible with SniHandler. However only the server attempts ALPN and verifies that it completes and the client doesn't verify the handshake is completed. This can lead to the client side SSL engine to prematurely close and throw an exception.
Modifications:
- The client should wait for the SSL handshake and ALPN to complete before the test exits.
Result:
SniHandlerTest.testSniWithApnHandler is more reliable.
Motivation:
ApplicationProtocolNegotiationHandler attempts to get a reference to an SslHandler in handlerAdded, but when SNI is in use the actual SslHandler will be added to the pipeline dynamically at some later time. When the handshake completes ApplicationProtocolNegotiationHandler throws an IllegalStateException because its reference to SslHandler is null.
Modifications:
- Instead of saving a reference to SslHandler in handlerAdded just search the pipeline when the SslHandler is needed
Result:
ApplicationProtocolNegotiationHandler support SniHandler.
Fixes https://github.com/netty/netty/issues/5066
