infinite loop
Motivation:
If SslHandler sets jdkCompatibilityMode to false and ReferenceCountedOpenSslEngine sets jdkCompatibilityMode to true there is a chance we will get stuck in an infinite loop if the peer sends a TLS packet with length greater than 2^14 (the maximum length allowed in the TLS 1.2 RFC [1]). However there are legacy implementations which actually send larger TLS payloads than 2^14 (e.g. OpenJDK's SSLSessionImpl [2]) and in this case ReferenceCountedOpenSslEngine will return BUFFER_OVERFLOW in an attempt to notify that a larger buffer is to be used, but if the buffer is already at max size this process will repeat indefinitely.
[1] https://tools.ietf.org/html/rfc5246#section-6.2.1
[2] http://hg.openjdk.java.net/jdk8u/jdk8u/jdk/file/d5a00b1e8f78/src/share/classes/sun/security/ssl/SSLSessionImpl.java#l793
Modifications:
- Support TLS payload sizes greater than 2^14 in ReferenceCountedOpenSslEngine
- ReferenceCountedOpenSslEngine should throw an exception if a
BUFFER_OVERFLOW is impossible to rectify
Result:
No more infinite loop in ReferenceCountedOpenSslEngine due to
BUFFER_OVERFLOW and large TLS payload lengths.
Motivation:
We need to upgrade our dependencies to versions which use ASM 6.0.0+ to support compiling on java9.
Modifications:
Update animal-sniffer-maven-plugin and maven-shade-plugin.
Result:
Fixes https://github.com/netty/netty/issues/6100
Motivation:
Getting the latest Conscrypt goodies.
Modifications:
A few API changes have occurred, specifically in the Conscrypt
class.
Result:
Netty now builds and tests against Conscrypt 1.0.0.RC11
Motivation:
Netty is unable to use Java9s ALPN support atm.
Modifications:
When running on Java9+ we invoke the correct methods that are exposed on the Java9+ implementation of SSLEngine and so be able to support ALPN.
This patch is based on the work of @rschmitt and so https://github.com/netty/netty/pull/6992.
Result:
Fixes#6933.
Motivation:
Remove Unsafe dependency for Atomic queues in JCTools, resolved in version 2.1.0
Modification:
Change pom JCTools version
Result:
Fixes#7117
Motivation:
We recently changed netty-tcnative to use underscores in its native library names.
Modifications:
Update code to use underscores when loading native library.
Result:
More consistent code.
Motivation:
To be able to build with latest java9 release we need to adjust commons-lang version and maven-enforcer-plugin.
Modifications:
- Use commons-lang 2.6.0
- Use maven-enforcer-plugin 3.0.0.M1 when building with java9
Result:
Netty builds again with latest java9 release
Motivation:
We used asm 6.0_ALPHA when building on java9 as the latest stable release not works with java9. asm 6.0_BETA was just released so we should update.
Modifications:
Upgrade asm version
Result:
Not use ALPHA release anymore
Motivation:
Starting with 1.0.0.RC9, conscrypt supports a buffer allocator.
Modifications:
- Updated the creation process for the engine to pass through the
ByteBufAllocator.
- Wrap a ByteBufAllocator with an adapter for conscrypt.
- Added a property to optionally control whether conscrypt uses
Netty's buffer allocator.
Result:
Netty+conscrypt will support using Netty's ByteBufAllocator.
Motivation:
JCTools 2.0.2 provides an unbounded MPSC linked queue. Before we shaded JCTools we had our own unbounded MPSC linked queue and used it in various places but gave this up because there was no public equivalent available in JCTools at the time.
Modifications:
- Use JCTool's MPSC linked queue when no upper bound is specified
Result:
Fixes https://github.com/netty/netty/issues/5951
Motivation:
Docker's `--tmpfs` flag mounts the temp volume with `noexec` by default,
resulting in an UnsatisfiedLinkError. While this is good security
practice, it is a surprising failure from a seemingly innocuous flag.
Modifications:
Add a best-effort attempt in `NativeLibraryLoader` to detect when temp
files beng loaded cannot be executed even when execution permissions
are set, often because the `noexec` flag is set on the volume.
Requires numerous additional exclusions to the Animal Sniffer config
for Java7 POSIX permissions manipulation.
Result:
Fixes [#6678].
Motivation:
As we now include native code for multiple platforms we need to generate an uber all jar before release it from the staging repository. For this the uber-staging profile can be used. To create a snapshot uber jar the uber-snapshot profile can be used.
Modifications:
- Add uber-staging and uber-snapshot profile
- Correct comment in pom.xml file to show usage.
Result:
Easier to create snapshot and release uber jars.
Motivation:
To ensure the release plugin works correctly we need to ensure all modules are included during build.
Modification:
- Include all modules
- Skip compilation and tests for native code when not supported but still include the module and build the jar
Result:
Build and release works again
Motivation:
When adding SNIMatcher support we missed to use static delegating methods and so may try to load classes that not exists in Java7. Which will lead to errors.
Modifications:
- Correctly only try to load classes when running on java8+
- Ensure Java8+ related tests only run when using java8+
Result:
Fixes [#6700]
Motivation:
We currently don't have a native transport which supports kqueue https://www.freebsd.org/cgi/man.cgi?query=kqueue&sektion=2. This can be useful for BSD systems such as MacOS to take advantage of native features, and provide feature parity with the Linux native transport.
Modifications:
- Make a new transport-native-unix-common module with all the java classes and JNI code for generic unix items. This module will build a static library for each unix platform, and included in the dynamic libraries used for JNI (e.g. transport-native-epoll, and eventually kqueue).
- Make a new transport-native-unix-common-tests module where the tests for the transport-native-unix-common module will live. This is so each unix platform can inherit from these test and ensure they pass.
- Add a new transport-native-kqueue module which uses JNI to directly interact with kqueue
Result:
JNI support for kqueue.
Fixes https://github.com/netty/netty/issues/2448
Fixes https://github.com/netty/netty/issues/4231
Motivation:
There needs to be some work be done to allow using forbidden API check plugin when using java9.
Modifications:
Skip forbidden API check when using java9
Result:
Builds again with java9
Motivation:
In cases when an application is running in a container or is otherwise
constrained to the number of processors that it is using, the JVM
invocation Runtime#availableProcessors will not return the constrained
value but rather the number of processors available to the virtual
machine. Netty uses this number in sizing various resources.
Additionally, some applications will constrain the number of threads
that they are using independenly of the number of processors available
on the system. Thus, applications should have a way to globally
configure the number of processors.
Modifications:
Rather than invoking Runtime#availableProcessors, Netty should rely on a
method that enables configuration when the JVM is started or by the
application. This commit exposes a new class NettyRuntime for enabling
such configuraiton. This value can only be set once. Its default value
is Runtime#availableProcessors so that there is no visible change to
existing applications, but enables configuring either a system property
or configuring during application startup (e.g., based on settings used
to configure the application).
Additionally, we introduce the usage of forbidden-apis to prevent future
uses of Runtime#availableProcessors from creeping. Future work should
enable the bundled signatures and clean up uses of deprecated and
other forbidden methods.
Result:
Netty can be configured to not use the underlying number of processors,
but rather the constrained number of processors.
https://github.com/netty/netty-tcnative/pull/215
Motivation
OCSP stapling (formally known as TLS Certificate Status Request extension) is alternative approach for checking the revocation status of X.509 Certificates. Servers can preemptively fetch the OCSP response from the CA's responder, cache it for some period of time, and pass it along during (a.k.a. staple) the TLS handshake. The client no longer has to reach out on its own to the CA to check the validity of a cetitficate. Some of the key benefits are:
1) Speed. The client doesn't have to crosscheck the certificate.
2) Efficiency. The Internet is no longer DDoS'ing the CA's OCSP responder servers.
3) Safety. Less operational dependence on the CA. Certificate owners can sustain short CA outages.
4) Privacy. The CA can lo longer track the users of a certificate.
https://en.wikipedia.org/wiki/OCSP_staplinghttps://letsencrypt.org/2016/10/24/squarespace-ocsp-impl.html
Modifications
https://www.openssl.org/docs/man1.0.2/ssl/SSL_set_tlsext_status_type.html
Result
High-level API to enable OCSP stapling
Motivation:
In OpenSslCertificateException we tried to validate the supplied error code but did not correctly account for all different valid error codes and so threw an IllegalArgumentException.
Modifications:
- Fix validation by updating to latest netty-tcnative and use CertificateVerifier.isValid
- Add unit tests
Result:
Validation of error code works as expected.
Motivation:
Conscrypt is a Java Security provider that wraps OpenSSL (specifically BoringSSL). It's a possible alternative to Netty-tcnative that we should explore. So this commit is just to enable us to further investigate its use.
Modifications:
Modifying the SslContext creation path to support the Conscrypt provider.
Result:
Netty will support OpenSSL with conscrypt.
Motivation:
Projects may import multiple libraries which use different versions of Netty.
Modifications:
Add 'netty-bom' meta-project that contains the other projects in a dependencyManagement section.
Result:
Developers can import the BOM to enforce specific version of Netty.
Motivation:
We not support all SSLParameters settings so we should better throw if a user try to use them.
Modifications:
- Check for unsupported parameters
- Add unit test
Result:
Less surprising behavior.
Motivation:
We should move the AutobahnTestsuite to an extra module. This allows easier to run only the testsuite or only the autobahntestsuite
Modifications:
Create a new module (testsuite-autobahn)
Result:
Better project structure.
Motivation:
autobahntestsuite-maven-plugin 0.1.4 was released and supports Java9.
Modifications:
Update plugin to be able to run tests on Java9
Result:
Autobahntestsuite can also be run on Java9.
Motivation:
OpenSSL doesn't automatically verify hostnames and requires extract method calls to enable this feature [1]. We should allow this to be configured.
Modifications:
- SSLParamaters#getEndpointIdentificationAlgorithm() should be respected and configured via tcnative interfaces.
Result:
OpenSslEngine respects hostname verification.
[1] https://wiki.openssl.org/index.php/Hostname_validation
Motivation:
We have our own ThreadLocalRandom implementation to support older JDKs . That said we should prefer the JDK provided when running on JDK >= 7
Modification:
Using ThreadLocalRandom implementation of the JDK when possible.
Result:
Make use of JDK implementations when possible.
Motivation:
We missed some stuff in 5728e0eb2c and so the build failed on java9
Modifications:
- Add extra cmdline args when needed
- skip the autobahntestsuite as jython not works with java9
- skip the osgi testsuite as the maven plugin not works with java9
Result:
Build finally passed on java9
Motivation:
Commit 591293bfb4 changed the build to need java8 but missed to adjust the enforce rule as well.
Modifications:
Enforce java8+
Result:
Quickly fail when user tries to compile with pre java8
Motivation:
Java8 is out now for some time and JDK7 is no longer supported officially. We should remove all our backports and just use what the JDK provides us. This also will allow us to use intrinsics that are offered by the JDK implementations.
Modifications:
Remove all backports of jdk8 classes.
Result:
Use what the JDK offers us. This also fixes [#5458]
Motivation:
tcnative was moved into an internal package.
Modifications:
Update package for tcnative imports.
Result:
Use correct package names for tcnative.
Motivation:
We need to pass special arguments to run with jdk9 as otherwise some tests will not be able to run.
Modifications:
Allow to define extra arguments when running with jdk9
Result:
Tests pass with jdk9
Motivation:
As we now need to compile with java8 we should still allow to run the tests with a different java version to ensure everythin also works with java 7 and 6.
Modifications:
Allow to pass "-DtestJavaHome" to the build and so use a different java version during running the tests.
Result:
Be able to run tests with different java versions.
Motivation:
tcnative has updated how constants are defined and removed some constants which are either obsolete or now set directly in tcnative.
Modifications:
- update to compile against tcnative changes.
Result:
Netty compiles with tcnative options changes.
Motivation:
Currently Netty utilizes BIO_new_bio_pair so we can control all FD lifetime and event notification but delegates to OpenSSL for encryption/decryption. The current implementation sets up a pair of BIO buffers to read/write encrypted/plaintext data. This approach requires copying of data from Java ByteBuffers to native memory BIO buffers, and also requires both BIO buffers to be sufficiently large to hold application data. If direct ByteBuffers are used we can avoid coyping to/from the intermediate BIO buffer and just read/write directly from the direct ByteBuffer memory. We still need an internal buffer because OpenSSL may generate write data as a result of read calls (e.g. handshake, alerts, renegotiation, etc..), but this buffer doesn't have to be be large enough to hold application data.
Modifications:
- Take advantage of the new ByteBuffer based BIO provided by netty-tcnative instead of using BIO_read and BIO_write.
Result:
Less copying and lower memory footprint requirement per TLS connection.
Motivation:
We used various mocking frameworks. We should only use one...
Modifications:
Make usage of mocking framework consistent by only using Mockito.
Result:
Less dependencies and more consistent mocking usage.
Motivation:
Previous versions of netty-tcnative used the org.apache.tomcat namespace which could lead to problems when a user tried to use tomcat and netty in the same app.
Modifications:
Use netty-tcnative which now uses a different namespace and adjust code to some API changes.
Result:
Its now possible to use netty-tcnative even when running together with tomcat.
Motivation:
We need to update jetty-alpn-agent to support latest JDK releases.
Modifications:
Update jetty-alpn-agent to 2.0.6
Result:
Be able to run tests with latest JDK releases.
Motivation:
When an empty hostname is used in DnsNameResolver.resolve*(...) it will never notify the future / promise. The root cause is that we not correctly guard against errors of IDN.toASCII(...) which will throw an IllegalArgumentException when it can not parse its input. That said we should also handle an empty hostname the same way as the JDK does and just use "localhost" when this happens.
Modifications:
- If the try to resolve an empty hostname we use localhost
- Correctly guard against errors raised by IDN.toASCII(...) so we will always noify the future / promise
- Add unit test.
Result:
DnsNameResolver.resolve*(...) will always notify the future.
Motivation:
Openssl provider should behave same as JDK provider when mutual authentication is required and a specific set of trusted Certificate Authorities are specified. The SSL handshake should return back to the connected peer the same list of configured Certificate Authorities.
Modifications:
Correctly set the CA list.
Result:
Correct and same behaviour as the JDK implementation.
Motivation:
Often its useful to run the tests with different commandline arguments (like different system properties).
Modifications:
Introduce argLine.javaProperties which can be set from the commandline as well to add arguments that should be append when run the unit tests.
Result:
More flexible way to run the tests.
Motivation:
Java9 will be released soon so we should ensure we can compile netty with Java9 and run all our tests. This will help to make sure Netty will be usable with Java9.
Modification:
- Add some workarounds to be able to compile with Java9, note that the full profile is not supported with Java9 atm.
- Remove some usage of internal APIs to be able to compile on java9
- Not support Alpn / Npn and so not run the tests when using Java9 for now. We will do a follow up PR to add support.
Result:
Its possible to build netty and run its testsuite with Java9.
Motivation:
We tried to detect the correct alert to use depending on the CertificateException that is thrown by the TrustManager. This not worked all the time as depending on the TrustManager implementation it may also wrap a CertPathValidatorException.
Modification:
- Try to unwrap the CertificateException if needed and detect the right alert via the CertPathValidatorException.
- Add unit to verify
Result:
Send the correct alert depending on the CertificateException when using OpenSslEngine.
Motivation:
A new version of centos was released we should verify against it when release.
Modifications:
Bump up version.
Result:
Release on latest centos version.
Motivation:
Add test-case for doing mutal auth with a certificate chain that holds more then one certificate.
Modifications:
Add test case
Result:
more tests.
Motivation:
For the leak profile we attempted to increase the number of leak hints that were retained to make debugging easier, but there was a typo.
Modifications:
- maxRecord -> maxRecords
Result:
Fix typo in pom.xml so leak profile provides more context for leaks.
Motivation:
Since netty shaded JCTools the OSGi manifest no longer is correct. It claims to
have an optional import "org.jctools.queues;resolution:=optional,org.jctools.qu
eues.atomic;resolution:=optional,org.jctools.util;resolution:=optional"
However since it is shaded, this is no longer true.
This was noticed when making JCTools a real bundle and netty resolved it as
optional import.
Modifications:
Modify the generated manifest by no longer analyzing org.jctools for imports.
A manual setting of sun.misc as optional was required.
Result:
Netty OSGi bundle will no longer interfere with a JCTools bundle.
Motivation:
We need to ensure we not set duplicated certificates when using OpenSslEngine.
Modifications:
- Skip first cert in chain when set the chain itself and so not send duplicated certificates
- Add interopt unit tests to ensure no duplicates are send.
Result:
No more duplicates.
Motiviation:
Previously the way how CertificateRequestCallback was working had some issues which could cause memory leaks and segfaults. Due of this tcnative code was updated to change the signature of the method provided by the interface.
Modifications:
Update CertificateRequestCallback implementations to match new interface signature.
Result:
No more segfaults / memory leaks when using boringssl or openssl >= 1.1.0
Motivation:
We use often javachannel().socket().* in NIO as these methods exists in java6. The problem is that these will throw often very general Exceptions (Like SocketException) while it is more expected to throw the Exceptions listed in the nio interfaces. When possible we should use the new methods available in java7+ which throw the correct exceptions.
Modifications:
Check for java version and depending on it using the socket or the javachannel.
Result:
Throw expected Exceptions.
Motivation:
netty-tcnative API has changed to remove a feature that contributed to a memory leak.
Modifications:
- Update to use the modified netty-tcnative API
Result:
Netty can use the latest netty-tcnative.
Motivation:
The log4j2 project has released version 2.6.2, a bug fix release of
log4j2.
Modifications:
The commit upgrades the log4j2 dependency by modifying the
log4j2.version property in the parent POM to contain version 2.6.2.
Result:
The log4j2 dependency is upgraded to version 2.6.2.
Motivation:
When the user constructs Lz4FrameDecoder with a Checksum implementation like CRC32 or Adler32 and uses Java8 we can directly use a ByteBuffer to do the checksum work. This way we can eliminate memory copies.
Modifications:
Detect if ByteBuffer can be used for checksum work and if so reduce memory copies.
Result:
Less memory copies when using JDK8
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:
It is good to have used dependencies and plugins up-to-date to fix any undiscovered bug fixed by the authors.
Modification:
Scanned dependencies and plugins and carefully updated one by one.
Result:
Dependencies and plugins are up-to-date.
Motivation:
When the user home and so the path to the local maven repository contains spaces it currently fails to run the tests (at least on windows).
Modifications:
Put double quotes around the ${settings.localRepository}
Result:
Be able to run build and tests even when user home path has spaces in it.
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:
Currently the default log level when running tests is debug. When
running the build on the CI server it might be nice to avoid this debug
level and allow for the level to be configured.
Modifications:
Added a logback-test.xml configuration that has been added to the
common module. This allows for the logLevel to be configured.
The default level will still be debug.
Result:
The log level can now be configured from the command line:
$ mvn test -DlogLevel=error
Motivation:
Before release 4.1.0.Final we should update all our dependencies.
Modifications:
Update dependencies.
Result:
Up-to-date dependencies used.
Motivation:
As we only provide tcnative jars for 64bit we should enforce 64bit when try to build netty, to make it easier for the user to understand why the build fails.
Modifications:
Add enforce rule.
Result:
Ensure 64bit is used when build netty.
Motivation:
When writing a SMTP client a provided SMTP codec that follows RFC2821 is useful.
Modification:
Add client side codec and test.
Results:
People who want to write a SMTP client can reuse the codec.
Motivation:
See #3095
Modifications:
Add Log4J2LoggerFactory and Log4J2Logger which is an InternalLogger implementation based on log4j2.
Result:
The user can use log4j2 directly without a special slf4j binding.
Motivation:
We should upgrade to latest netty-tcnative version.
Modifications:
Upgrade to version 1.1.33.Fork15
Result:
Latest netty-tcnative version is used.
Motivation:
See #3172
Modifications:
https://github.com/netty/netty-build/pull/6 added a junit timeout listener to the netty-build project. This patch just set it up.
Result:
If a test is set the timeout parameter using junit's @Test(timeout = ...) and the timeout is triggered, a full stack trace dump will be outputted and also output the deadlocks if any.
Motivation:
See https://github.com/netty/netty-build/issues/5
Modifications:
Add xml-maven-plugin to check indentation and fix violations
Result:
pom.xml will be checked in the PR build
Motivation:
Build warning message is shown when building netty project. Due to missing paxexam version below[1] warning message is shown when building netty project.
Modifications:
Added paxexam plugin version into root pom
Result:
paxexam related warning will not be displayed when building the project.
[1]. #4909
Motivation:
Depending on the actual CertificateException we should set the correct alert type so it will be sent back to the remote peer and so make it easier for them to fix it.
Modification:
Correctly set the alert and not always just use a general alert.
Result:
It's easier for the remote peer to fix the problems.
Motivation:
netty-tcnative-1.1.33.Fork was released, we should upgrade. Also we should skip renegotiate tests if boringssl is used because boringssl does not support renegotiation.
Modifications:
- Upgrade to netty-tcnative-1.1.33.Fork13
- Skip renegotiate tests if boringssl is used.
Result:
Use newest version of netty-tcnative and be able to build if boringssl is used.
Motivation:
ResourceLeakDetector enforces a limit as to how large the queue is allowed to grow for stack traces in order to keep memory from growing too large. However it is not always clear when records are dropped, or how many have been dropped. This can make interpreting leak reports more difficult if you assume all information is present when it may not be. Also we should increase the limit (currently 4) when running tests on the CI servers.
Modifications:
- Increase leak detector record limit on CI servers from 4 to 32.
- Track how many records have been discarded and disclose this in the leak report.
Result:
Leak reports clarify how many records were dropped, and how to increase the limit.
Motivation:
We had reports of failures before when sun.misc.Unsafe was not present. We should run our tests also with it disable to ensure everything works even if sun.misc.Unsafe is not present on the system.
Modifications:
Add a new profile which allows to run tests without Unsafe (using -PnoUnsafe)
Result:
Better testing of netty for systems where sun.misc.Unsafe is not present.
Motivation:
Builds fail with java 1.8.0_72 because jetty-alpn-boot has absorbed new code from openjdk and older version are now incompatible.
Modifications:
- Updated jetty-alpn-agent version
Result:
We can now build/develop using java 1.8.0_72
Motivation:
When using SslProvider.OPENSSL we currently not handle SNI on the client side.
Modifications:
Correctly enable SNI when using clientMode and peerHost != null.
Result:
SNI works even with SslProvider.OPENSSL.
Motivation:
As we now can easily build static linked versions of tcnative it makes sense to run our netty build against all of them.
This helps to ensure our code works with libressl, openssl and boringssl.
Modifications:
Allow to specify -Dtcnative.artifactId= and -Dtcnative.version=
Result:
Easy to run netty build against different tcnative flavors.
Motivation:
Attempts to enable SSL protocols which are currently disabled fail when using the OpenSslEngine. Related to https://github.com/netty/netty/issues/4736
Modifications:
Clear out all options that have disabled SSL protocols before attempting to enable any SSL protocol.
Result:
setEnabledProtocols works as expected.
Motivation:
Netty was missing support for Protobuf nano runtime targeted at
weaker systems such as Android devices.
Modifications:
Added ProtobufDecoderNano and ProtobufDecoderNano
in order to provide support for Nano runtime.
modified ProtobufVarint32FrameDecoder and
ProtobufLengthFieldPrepender in order to remove any
on either Nano or Lite runtime by copying the code
for handling Protobuf varint32 in from Protobuf
library.
modified Licenses and NOTICE in order to reflect the
changes i made.
added Protobuf Nano runtime as optional dependency
Result:
Netty now supports Protobuf Nano runtime.
Motivation:
Parent pom.xml uses deprecated maven expressions, such as `${groupId}`
which should be ${project.groupId}.
This causes tons of warnings on every module in the build.
Modifications:
Use up to date syntax.
Result:
No more maven warnings.
Motivation:
We had to add a new profile for each OpenJDK/OracleJDK release to make
Maven choose the correct alpn-boot.jar and npn-boot.jar. As a result,
our pom.xml has a large number of `<profile/>` sections.
Modifications:
- Use jetty-alpn-agent, which chooses the correct alpn-boot.jar and
npn-boot.jar automatically to remove all the nasty profile sections
from pom.xml
- Visit https://github.com/trustin/jetty-alpn-agent for more info
Result:
Cleaner pom.xml
