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= sshj - SSHv2 library for Java Jeroen van Erp :sshj_groupid: com.hierynomus :sshj_version: 0.32.0 :source-highlighter: pygments

image:https://github.com/hierynomus/sshj/actions/workflows/gradle.yml/badge.svg[link="https://github.com/hierynomus/sshj/actions/workflows/gradle.yml"] image:https://app.codacy.com/project/badge/Grade/2c8a5a67c6a54ed89c9a699fd6b27305["Codacy Grade", link="https://app.codacy.com/gh/hierynomus/sshj"] image:https://codecov.io/gh/hierynomus/sshj/branch/master/graph/badge.svg["codecov", link="https://codecov.io/gh/hierynomus/sshj"] image:http://www.javadoc.io/badge/com.hierynomus/sshj.svg?color=blue["JavaDocs", link="http://www.javadoc.io/doc/com.hierynomus/sshj"] image:https://maven-badges.herokuapp.com/maven-central/com.hierynomus/sshj/badge.svg["Maven Central",link="https://maven-badges.herokuapp.com/maven-central/com.hierynomus/sshj"]

To get started, have a look at one of the examples. Hopefully you will find the API pleasant to work with :)

== Getting SSHJ

To get SSHJ, you have two options:

. Add a dependency to SSHJ to your project. . Build SSHJ yourself.

And, if you want, you can also run the SSHJ examples.

Binary releases of SSHJ are not provided here, but you can download it http://search.maven.org/#artifactdetails%7C{sshj_groupid}%7Csshj%7C{sshj_version}%7Cjar[straight from the Maven Central repository] if you want to.

== Depending on SSHJ If you're building your project using Maven, you can add the following dependency to the pom.xml:

[source,xml,subs="verbatim,attributes"]

If your project is built using another build tool that uses the Maven Central repository, translate this dependency into the format used by your build tool.

== Building SSHJ . Clone the SSHJ repository. . Ensure you have Java6 installed with the http://www.oracle.com/technetwork/java/javase/downloads/jce-6-download-429243.html[Unlimited strength Java Cryptography Extensions (JCE)]. . Run the command ./gradlew clean build.

== Running the examples In the examples directory, there is a separate Maven project that shows how the library can be used in some sample cases. If you want to run them, follow these guidelines:

. Install http://maven.apache.org/[Maven 2.2.1] or up. . Clone the Overthere repository. . Go into the examples directory and run the command mvn eclipse:eclipse. . Import the examples project into Eclipse. . Change the login details in the example classes (address, username and password) and run them!

== Features of the library include:

• reading known_hosts files for host key verification
• publickey, password and keyboard-interactive authentication
• command, subsystem and shell channels
• local and remote port forwarding
• scp + complete sftp version 0-3 implementation

== Supported algorithms Implementations / adapters for the following algorithms are included:

ciphers:: aes{128,192,256}-{cbc,ctr}, aes{128,256}[email protected], blowfish-{cbc,ctr}, [email protected], 3des-{cbc,ctr}, twofish{128,192,256}-{cbc,ctr}, twofish-cbc, serpent{128,192,256}-{cbc,ctr}, idea-{cbc,ctr}, cast128-{cbc,ctr}, arcfour, arcfour{128,256} SSHJ also supports the following extended (non official) ciphers: camellia{128,192,256}-{cbc,ctr}, camellia{128,192,256}-{cbc,ctr}@openssh.org

key exchange:: diffie-hellman-group1-sha1, diffie-hellman-group14-sha1, diffie-hellman-group14-sha256, diffie-hellman-group15-sha512, diffie-hellman-group16-sha512, diffie-hellman-group17-sha512, diffie-hellman-group18-sha512 diffie-hellman-group-exchange-sha1, diffie-hellman-group-exchange-sha256, ecdh-sha2-nistp256, ecdh-sha2-nistp384, ecdh-sha2-nistp521, [email protected]

SSHJ also supports the following extended (non official) key exchange algorithms: [email protected], diffie-hellman-group15-sha256, [email protected], [email protected], diffie-hellman-group16-sha256, [email protected], [email protected], [email protected]

signatures:: ssh-rsa, ssh-dss, ecdsa-sha2-nistp256, ecdsa-sha2-nistp384, ecdsa-sha2-nistp521, ssh-ed25519, ssh-rsa2-256, ssh-rsa2-512

mac:: hmac-md5, hmac-md5-96, hmac-sha1, hmac-sha1-96, hmac-sha2-256, hmac-sha2-512, hmac-ripemd160, [email protected] [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected]

compression:: zlib and [email protected] (delayed zlib)

private key files:: pkcs5, pkcs8, openssh-key-v1, [email protected], [email protected]

If you need something that is not included, it shouldn't be too hard to add (do contribute it!)

== Comparing to other implementations http://ssh-comparison.quendi.de/comparison.html[SSH Implementation Comparison]

== Dependencies Java 6+. http://www.slf4j.org/download.html[slf4j] is required. http://www.bouncycastle.org/java.html[bouncycastle] is highly recommended and required for using some of the crypto algorithms. http://www.jcraft.com/jzlib/[jzlib] is required for using zlib compression.

== Reporting bugs Issue tracker: https://github.com/hierynomus/sshj/issues

== Contributing Fork away!

== Release history SSHJ 0.34.0 (2022-08-10)::

• Merged https://github.com/hierynomus/sshj/pull/743[#743]: Use default client credentials for AuthGssApiWithMic
• Merged https://github.com/hierynomus/sshj/pull/801[#801]: Restore thread interrupt status after catching InterruptedException
• Merged https://github.com/hierynomus/sshj/pull/793[#793]: Merge PKCS5 and PKCS8 classes
• Upgraded dependencies SLF4J (1.7.36) and Logback (1.2.11)
• Merged https://github.com/hierynomus/sshj/pull/791[#791]: Update KeepAlive examples
• Merged https://github.com/hierynomus/sshj/pull/775[#775]: Add SFTP resume support SSHJ 0.33.0 (2022-04-22)::
• Upgraded dependencies BouncyCastle (1.70)
• Merged https://github.com/hierynomus/sshj/pull/687[#687]: Correctly close connection when remote closes connection.
• Merged https://github.com/hierynomus/sshj/pull/741[#741]: Add support for testcontainers in test setup to test more scenarios
• Merged https://github.com/hierynomus/sshj/pull/733[#733]: Send correct key proposal if client knows CA key
• Merged https://github.com/hierynomus/sshj/pull/746[#746]: Fix bug in reading Putty private key file with passphrase
• Merged https://github.com/hierynomus/sshj/pull/742[#742]: Use Config.keyAlgorithms to determine rsa-sha2 support
• Merged https://github.com/hierynomus/sshj/pull/754[#754]: Use SFTP protocol version to set FXP rename flags conditionally
• Merged https://github.com/hierynomus/sshj/pull/752[#752]: Correctly start and terminate KeepAlive thread
• Merged https://github.com/hierynomus/sshj/pull/753[#753]: Provide better thread names
• Merged https://github.com/hierynomus/sshj/pull/724[#724]: Add parameter to limit read ahead length
• Merged https://github.com/hierynomus/sshj/pull/763[#763]: Try all public key algorithms for a specific key type
• Merged https://github.com/hierynomus/sshj/pull/756[#756]: Remove deprecated proxy connect methods
• Merged https://github.com/hierynomus/sshj/pull/770[#770]: Add support for ed25519 aes-128-cbc keys
• Merged https://github.com/hierynomus/sshj/pull/773[#773]: Fix NPE when reading empty OpenSSHKeyV1KeyFile
• Merged https://github.com/hierynomus/sshj/pull/777[#777]: Don't request too many read-ahead packets

SSHJ 0.32.0 (2021-10-12)::

• Send EOF on channel close (Fixes https://github.com/hierynomus/sshj/issues/143[#143], https://github.com/hierynomus/sshj/issues/496[#496], https://github.com/hierynomus/sshj/issues/553[#553], https://github.com/hierynomus/sshj/issues/554[#554])
• Merged https://github.com/hierynomus/sshj/pull/726[#726]: Parse OpenSSH v1 keys with full CRT information present
• Merged https://github.com/hierynomus/sshj/pull/721[#721]: Prefer known host key algorithm for host key verification
• Merged https://github.com/hierynomus/sshj/pull/716[#716], https://github.com/hierynomus/sshj/pull/729[#729] and https://github.com/hierynomus/sshj/pull/730[#730]: Add full support for PuTTY v3 key files.
• Merged https://github.com/hierynomus/sshj/pull/708[#708] and https://github.com/hierynomus/sshj/pull/713[#71]: Add support for PKCS#8 private keys
• Merged https://github.com/hierynomus/sshj/pull/703[#703]: Support host certificate keys
• Upgraded dependencies BouncyCastle (1.69), SLF4j (1.7.32), Logback (1.2.6), asn-one (0.6.0)
• Merged https://github.com/hierynomus/sshj/pull/702[#702]: Support Public key authentication using certificates
• Merged https://github.com/hierynomus/sshj/pull/691[#691]: Fix for writing negative unsigned integers to Buffer
• Merged https://github.com/hierynomus/sshj/pull/682[#682]: Support for [email protected] cipher
• Merged https://github.com/hierynomus/sshj/pull/680[#680]: Configurable preserve mtimes for SCP transfers

SSHJ 0.31.0 (2021-02-08)::

• Bump dependencies (asn-one 0.5.0, BouncyCastle 1.68, slf4j-api 1.7.30)
• Merged https://github.com/hierynomus/sshj/pull/660[#660]: Support ED25519 and ECDSA keys in PuTTY format
• Merged https://github.com/hierynomus/sshj/pull/655[#655]: Bump BouncyCastle due to CVE
• Merged https://github.com/hierynomus/sshj/pull/653[#653]: Make Parameters class useable as HashMap key
• Merged https://github.com/hierynomus/sshj/pull/647[#647]: Reduce log level for identification parser
• Merged https://github.com/hierynomus/sshj/pull/630[#630]: Add support for [email protected] and [email protected] ciphers
• Merged https://github.com/hierynomus/sshj/pull/636[#636]: Improved Android compatibility
• Merged https://github.com/hierynomus/sshj/pull/627[#627]: Prevent key leakage SSHJ 0.30.0 (2020-08-17)::
• BREAKING CHANGE: Removed setSignatureFactories and getSignatureFactories from the Config and switched them for getKeyAlgorithms and setKeyAlgorithms
• Fixed https://github.com/hierynomus/sshj/pull/588[#588]: Add support for ssh-rsa2-256 and ssh-rsa2-512 signatures
• Merged https://github.com/hierynomus/sshj/pull/579[#579]: Fix NPE in OpenSSHKnownHosts
• Merged https://github.com/hierynomus/sshj/pull/587[#587]: Add passwordfinder retry for OpenSSHKeyV1KeyFile
• Merged https://github.com/hierynomus/sshj/pull/586[#586]: Make KeyType compatible with Android Store
• Merged https://github.com/hierynomus/sshj/pull/593[#593]: Change UserAuth.getAllowedMethods() to Collection return type
• Merged https://github.com/hierynomus/sshj/pull/595[#595]: Allow reading arbitrary length keys
• Merged https://github.com/hierynomus/sshj/pull/591[#591]: Allow to query SFTP extensions
• Merged https://github.com/hierynomus/sshj/pull/603[#603]: Add method to create Stateful SFTP client
• Merged https://github.com/hierynomus/sshj/pull/605[#605]: Use Daemon threads to avoid blocking JVM shutdown
• Merged https://github.com/hierynomus/sshj/pull/606[#606]: Always use the JCERandom RNG by default
• Merged https://github.com/hierynomus/sshj/pull/609[#609]: Clear passphrase after use to prevent security issues
• Merged https://github.com/hierynomus/sshj/pull/618[#618]: Fix localport of DirectConnection for use with OpenSSH > 8.0
• Merged https://github.com/hierynomus/sshj/pull/619[#619]: Upgraded BouncyCastle to 1.66
• Merged https://github.com/hierynomus/sshj/pull/622[#622]: Send 'ext-info-c' with KEX algorithms
• Merged https://github.com/hierynomus/sshj/pull/623[#623]: Fix transport encoding of nistp521 signatures
• Merged https://github.com/hierynomus/sshj/pull/607[#607]: Fix mathing pubkeys to key algorithms
• Merged https://github.com/hierynomus/sshj/pull/602[#602]: Fix RSA certificate key determination SSHJ 0.27.0 (2019-01-24)::
• Fixed https://github.com/hierynomus/sshj/issues/415[#415]: Fixed wrongly prefixed '/' to path in SFTPClient.mkdirs
• Added support for ETM (Encrypt-then-Mac) MAC algorithms.
• Fixed https://github.com/hierynomus/sshj/issues/454[#454]: Added missing capacity check for Buffer.putUint64
• Fixed https://github.com/hierynomus/sshj/issues/466[#466]: Added lock timeout for remote action to prevent hanging
• Fixed https://github.com/hierynomus/sshj/issues/470[#470]: Made EdDSA the default (first) signature factory
• Fixed https://github.com/hierynomus/sshj/issues/467[#467]: Added AES256-CBC as cipher mode in openssh-key-v1 support
• Fixed https://github.com/hierynomus/sshj/issues/464[#464]: Enabled [email protected] in DefaultConfig
• Fixed https://github.com/hierynomus/sshj/issues/472[#472]: Handle server initiated global requests
• Fixed https://github.com/hierynomus/sshj/issues/485[#485]: Added support for all keytypes to openssh-key-v1 keyfiles. SSHJ 0.26.0 (2018-07-24)::
• Fixed https://github.com/hierynomus/sshj/issues/413[#413]: Use UTF-8 for PrivateKeyFileResource
• Fixed https://github.com/hierynomus/sshj/issues/427[#427]: Support encrypted ed25519 openssh-key-v1 files
• Upgraded BouncyCastle to 1.60
• Added support for [email protected] MAC SSHJ 0.24.0 (2018-04-04)::
• Added support for hmac-ripemd160
• Fixed https://github.com/hierynomus/sshj/issues/382[#382]: Fixed escaping in WildcardHostmatcher
• Added integration testsuite using Docker against OpenSSH
• Fixed https://github.com/hierynomus/sshj/issues/187[#187]: Fixed length bug in Buffer.putString
• Fixed https://github.com/hierynomus/sshj/issues/405[#405]: Continue host verification if first hostkey does not match. SSHJ 0.23.0 (2017-10-13)::
• Merged https://github.com/hierynomus/sshj/pull/372[#372]: Upgrade to 'net.i2p.crypto:eddsa:0.2.0'
• Fixed https://github.com/hierynomus/sshj/issues/355[#355] and https://github.com/hierynomus/sshj/issues/354[#354]: Correctly decode signature bytes
• Fixed https://github.com/hierynomus/sshj/issues/365[#365]: Added support for new-style OpenSSH fingerprints of server keys
• Fixed https://github.com/hierynomus/sshj/issues/356[#356]: Fixed key type detection for ECDSA public keys
• Made SSHJ Java9 compatible SSHJ 0.22.0 (2017-08-24)::
• Fixed https://github.com/hierynomus/sshj/pull/341[#341]: Fixed path walking during recursive copy
• Merged https://github.com/hierynomus/sshj/pull/338[#338]: Added ConsolePasswordFinder to read password from stdin
• Merged https://github.com/hierynomus/sshj/pull/336[#336]: Added support for ecdsa-sha2-nistp384 and ecdsa-sha2-nistp521 signatures
• Fixed https://github.com/hierynomus/sshj/issues/331[#331]: Added support for wildcards in known_hosts file SSHJ 0.21.1 (2017-04-25)::
• Merged https://github.com/hierynomus/sshj/pull/322[#322]: Fix regression from 40f956b (invalid length parameter on outputstream) SSHJ 0.21.0 (2017-04-14)::
• Merged https://github.com/hierynomus/sshj/pull/319[#319]: Added support for [email protected] and [email protected] certificate key files
• Upgraded Gradle to 3.4.1
• Merged https://github.com/hierynomus/sshj/pull/305[#305]: Added support for custom string encoding
• Fixed https://github.com/hierynomus/sshj/issues/312[#312]: Upgraded BouncyCastle to 1.56 SSHJ 0.20.0 (2017-02-09)::
• Merged https://github.com/hierynomus/sshj/pull/294[#294]: Reference ED25519 by constant instead of name
• Merged https://github.com/hierynomus/sshj/pull/293[#293], https://github.com/hierynomus/sshj/pull/295[#295] and https://github.com/hierynomus/sshj/pull/301[#301]: Fixed OSGi packaging
• Added new Diffie Hellman groups 15-18 for stronger KeyExchange algorithms SSHJ 0.19.1 (2016-12-30)::
• Enabled PKCS5 Key files in DefaultConfig
• Merged https://github.com/hierynomus/sshj/pull/291[#291]: Fixed sshj.properties loading and chained exception messages
• Merged https://github.com/hierynomus/sshj/pull/284[#284]: Correctly catch interrupt in keepalive thread
• Fixed https://github.com/hierynomus/sshj/issues/292[#292]: Pass the configured RandomFactory to Diffie Hellman KEX
• Fixed https://github.com/hierynomus/sshj/issues/256[#256]: SSHJ now builds if no git repository present
• LocalPortForwarder now correctly interrupts its own thread on close() SSHJ 0.19.0 (2016-11-25)::
• Fixed https://github.com/hierynomus/sshj/issues/276[#276]: Add support for ed-25519 and new OpenSSH key format
• Fixed https://github.com/hierynomus/sshj/issues/280[#280]: Read version from a generated sshj.properties file to correctly output version during negotiation SSHJ 0.18.0 (2016-09-30)::
• Fixed Android compatibility
• Upgrade to Gradle 3.0
• Merged https://github.com/hierynomus/sshj/pull/271[#271]: Load known_hosts without requiring BouncyCastle
• Merged https://github.com/hierynomus/sshj/pull/269[#269]: Brought back Java6 support by popular demand
• Merged https://github.com/hierynomus/sshj/pull/267[#267]: Added support for per connection logging (Fixes https://github.com/hierynomus/sshj/issues/264[#264])
• Merged https://github.com/hierynomus/sshj/pull/262[#262], https://github.com/hierynomus/sshj/pull/265[#265] and https://github.com/hierynomus/sshj/pull/266[#266]: Added PKCS5 key file support
• Fixed toString of sftp FileAttributes (Fixes https://github.com/hierynomus/sshj/pull/258[#258])
• Fixed https://github.com/hierynomus/sshj/issues/255[#255]: No longer depending on 'privately marked' classes in net.i2p.crypto.eddsa.math package, fixes OSGI dependencies SSHJ 0.17.2 (2016-07-07)::
• Treating SSH Server identification line ending in '\n' instead of '\r\n' leniently. SSHJ 0.17.1 (2016-07-06)::
• Improved parsing of the SSH Server identification. Too long header lines now no longer break the protocol. SSHJ 0.17.0 (2016-07-05)::
• Introduced breaking change in SFTP copy behaviour: Previously an SFTP copy operation would behave differently if both source and target were folders with different names. In this case instead of copying the contents of the source into the target directory, the directory itself was copied as a sub directory of the target directory. This behaviour has been removed in favour of the default behaviour which is to copy the contents of the source into the target. Bringing the behaviour in line with how SCP works.
• Fixed https://github.com/hierynomus/sshj/issues/252[#252] (via: https://github.com/hierynomus/sshj/pull/253[#253]): Same name subdirs are no longer merged by accident SSHJ 0.16.0 (2016-04-11)::
• Fixed https://github.com/hierynomus/sshj/issues/239[#239]: Remote port forwards did not work if you used the empty string as address, or a catch-all address.
• Fixed https://github.com/hierynomus/sshj/issues/242[#242]: Added OSGI headers to sources jar manifest
• Fixed https://github.com/hierynomus/sshj/issues/236[#236]: Remote Port forwarding with dynamic port allocation fails with BufferUnderflowException
• Upgraded gradle distribution to 2.12
• Closed https://github.com/hierynomus/sshj/issues/234[#234]: Dropped Java6 support (0.15.0 was already Java6 incompatible due to Java7 dependency)
• Fixed https://github.com/hierynomus/sshj/issues/118[#118]: Added configuration switch for waiting on a server ident before sending the client ident.
• Fixed https://github.com/hierynomus/sshj/issues/114[#114]: Added javadoc that you always need to call close() on a Command before inspecting the exit codes.
• Fixed https://github.com/hierynomus/sshj/issues/237[#237]: Fixed race condition if a [email protected] global request is received directly after a successful auth. SSHJ 0.15.0 (2015-11-20)::
• Fixed https://github.com/hierynomus/sshj/issues/220[#220]: Added support for ssh-ed25519 host keys
• Fixed https://github.com/hierynomus/sshj/issues/225[#225]: Fixed bug in ECDSA fingerprint calculation that sometimes produced an incorrect fingerprint
• Added arcfour Stream Ciphers from RFC4253 and RFC4345
• Added all Block Ciphers from RFC4344 and RFC4253 SSHJ 0.14.0 (2015-11-04)::
• Fixed https://github.com/hierynomus/sshj/issues/171[#171]: Added support for [email protected] key exchange algorithm
• Added support for ecdh-sha2-nistp256, ecdh-sha2-nistp384 and ecdh-sha2-nistp521 key exchange algorithms
• Fixed https://github.com/hierynomus/sshj/issues/167[#167]: Added support for diffie-hellman-group-exchange-sha1 and diffie-hellman-group-exchange-sha256 key exchange methods
• Fixed https://github.com/hierynomus/sshj/issues/212[#212]: Configure path escaping to enable shell expansion to work correctly
• Merged https://github.com/hierynomus/sshj/issues/210[#210]: RemoteFileInputStream.skip returns wrong value (Fixes https://github.com/hierynomus/sshj/issues/209[#209])
• Merged https://github.com/hierynomus/sshj/issues/208[#208]: Added SCP bandwidth limitation support
• Merged https://github.com/hierynomus/sshj/issues/211[#211]: Made keyfile format detection more robust SSHJ 0.13.0 (2015-08-18)::
• Merged https://github.com/hierynomus/sshj/issues/199[#199]: Fix for IndexOutOfBoundsException in ReadAheadRemoteFileInputStream, fixes https://github.com/hierynomus/sshj/issues/183[#183]
• Merged https://github.com/hierynomus/sshj/issues/195[#195]: New authentication supported: gssapi-with-mic
• Merged https://github.com/hierynomus/sshj/issues/201[#201]: New option to verify negotiated key exchange algorithms
• Merged https://github.com/hierynomus/sshj/issues/196[#196]: Fix for looking up complete hostname in known hosts file SSHJ 0.12.0 (2015-04-14)::
• Added support for HTTP proxies when running JDK6 or JDK7, fixes: https://github.com/hierynomus/sshj/issues/170[#170]
• Merged https://github.com/hierynomus/sshj/issues/186[#186]: Fix for detecting end-of-stream
• Compiling to JDK6, fixes https://github.com/hierynomus/sshj/issues/179[#179] and https://github.com/hierynomus/sshj/issues/185[#185]
• Correctly close socket and channel when LocalPortForwarder fails to open and start the channel (Fixes https://github.com/hierynomus/sshj/issues/175[#175] and https://github.com/hierynomus/sshj/issues/176[#176])
• Merged https://github.com/hierynomus/sshj/issues/181[#181]: Invalid write packet length when reading with offset (Fixes https://github.com/hierynomus/sshj/issues/180[#180]) SSHJ 0.11.0 (2015-01-23)::
• New maven coordinates com.hierynomus:sshj:0.11.0 as https://github.com/hierynomus[@hierynomus] took over as maintainer of SSHJ
• Migrated build system to Gradle 2.2.1
• Merged https://github.com/hierynomus/sshj/issues/150[#150]: Fix for incorrect file handle on some SSH servers, fixes: https://github.com/hierynomus/sshj/issues/54[#54], https://github.com/hierynomus/sshj/issues/119[#119], https://github.com/hierynomus/sshj/issues/168[#168], https://github.com/hierynomus/sshj/issues/169[#169]
• Made jzlib optional in OSGi bundling, fixes: https://github.com/hierynomus/sshj/issues/162[#162]
• Improved some log levels, fixes: https://github.com/hierynomus/sshj/issues/161[#161]
• Merged https://github.com/hierynomus/sshj/issues/156[#156], https://github.com/hierynomus/sshj/issues/164[#164], https://github.com/hierynomus/sshj/issues/165[#165]: Fixed block sizes for hmac-sha2-256 and hmac-sha2-512
• Merged https://github.com/hierynomus/sshj/issues/141[#141]: Add proxy support
• Merged https://github.com/hierynomus/sshj/issues/157[#157], https://github.com/hierynomus/sshj/issues/163[#163]: Doc and build fixes
• Upgraded BouncyCastle to 1.51, fixes: https://github.com/hierynomus/sshj/issues/142[#142]
• Implemented keep-alive with connection drop detection, fixes https://github.com/hierynomus/sshj/issues/166[#166]