Re-enable DSA, DSA_CERT, and RSA_CERT public key authentication.
DSA is discouraged for a long time already, but it might still be
way too disruptive to completely drop it. RSA is discouraged for
far less long, and dropping that would be really disruptive.

Adapt to the changed property handling. Remove work-arounds for
shortcomings of earlier sshd versions.

Use Orbit I20210203173513, which includes sshd 2.6.0. This also bumps
apache.httpclient to 4.5.13 and apache.httpcore to 4.4.14.

Change-Id: I2d24a1ce4cc9f616a94bb5c4bdaedbf20dc6638e
Signed-off-by: David Ostrovsky <david@ostrovsky.org>
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Also mark the return value @Nullable to enable null analysis in Eclipse.

Change-Id: Ib954b231d743da6ea122adb2cc4880b5f99824cc
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

SshSupport.runSshCommand() had a comment that wait with time-out
could not be used because JSchProcess.exitValue() threw the wrong
unchecked exception when the process was still running.

Fix this and make JSchProcess.exitValue() throw the right exception,
then wait with a time-out in SshSupport.

The Apache sshd client's SshdExecProcess has always used the correct
IllegalThreadStateException.

Add tests for SshSupport.runCommand().

Change-Id: Id30893174ae8be3b9a16119674049337b0cf4381
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Improve the SshTestGitServer API for accessing the server properties.
Instead of returning the raw property map, return the proper sshd API
abstraction PropertyResolver.

This makes the interface more resilient against upstream changes.

Change-Id: Ie5b685bddc4e59f3eb6c121026d3658d57618ca4
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Use standard java.security to generate test keys, use sshd to write
public key files, and write PKCS#8 PEM files for our non-encrypted
test private keys. This is a format that both JSch and Apache MINA
sshd can read.

Change-Id: I6ec55cfd7346b672a7fb6139d51abfb06d81a394
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

SSHD-1028:[1] server doesn't close server-side sessions properly when
client disconnects.

[1] https://issues.apache.org/jira/projects/SSHD/issues/SSHD-1028

Change-Id: I0d67f49e35abe8375cb1370a494dc01d0fb2c9b1
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Avoid using a key written to a file. This makes it clearer that
the test does not rely on files being present.

Change-Id: I31cf4f404aab5b891c32fc4bda906b7f8fe03777
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Change target platforms to Orbit I20200319180910 and regenerate them.
Change package imports to [2.4.0,2.5.0); adapt code to upstream API
changes.

Maven build: update version in root pom.

Bazel build: update version & hash in WORKSPACE file.

Proxy functionality verified manually using 3proxy (HTTP & SOCKS,
with basic authentication) and ssh -vvv -D7020 localhost (SOCKS, no
authentication).

Bug: 561078
Change-Id: I582f6b98055b013c006f2c749890fe6db801cbaa
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

This is the format given by the Eclipse legal doc generator [1].

[1] https://www.eclipse.org/projects/tools/documentation.php?id=technology.jgit

Bug: 548298
Change-Id: I8d8cabc998ba1b083e3f0906a8d558d391ffb6c4
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Change-Id: Ie2e207eb05e0f6da8018153f8a5dd636e8f35f4c
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

RFC 4253 section 4.2 allows an ssh server to send additional lines
before its server identification string. Apache MINA sshd enforces
for these lines the constraints specified for the server identification
line, too: no NUL characters and not longer than 255 characters. That
is too strict. RFC 4253 doesn't mandate this, and it also doesn't
make sense given the rationale for these lines in RFC 4253: a TCP
wrapper may not be aware of SSH restrictions, and may not adhere to
these constraints.

Be more lenient when parsing the server's protocol version. Allow
NULs and longer lines in the preamble, and also handle line endings
more leniently. Only enforce the restrictions for the actual server
identification line.

Bug: 545939
Change-Id: I75955e9d8a8daef7c04fc0f39539c2ee93514e1c
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Update target platforms, maven and bazel builds to use sshd 2.2.0.

Adapt internal classes to changed sshd interfaces and remove previous
work-arounds for asking repeatedly for key passwords and for loading
keys lazily; both are now done by sshd.

CQ: 19034
CQ: 19035
Bug: 541425
Change-Id: I85e1df6ebb8a94953a912d9b2b8a7b5bdfbd608a
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Add tests for password and keyboard-interactive authentication.
Implement password authentication; the default provided by sshd
is non-interactive, which is not useful for JGit.

Make sure the CredentialsProvider gets reset on successive password
retrieval attempts. Otherwise it might always return the same non-
accepted password from a secure storage. (That one was discovered
by actually trying this via EGit; the JGit tests don't catch this.)

Change the default order of authentication mechanisms to prefer
password over keyboard-interactive. This is a mitigation for upstream
bug SSHD-866.[1]

Also include a fix for upstream bug SSHD-867.[2]

[1] https://issues.apache.org/jira/projects/SSHD/issues/SSHD-866
[2] https://issues.apache.org/jira/projects/SSHD/issues/SSHD-867

Bug: 520927
Change-Id: I423e548f06d3b51531016cf08938c8bd7acaa2a9
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Create the bundle and move the SshTestGitServer there. Verified that
the Eclipse build still works and ran JSchSshTest and ApacheSshTest as
junit tests inside Eclipse.

Update maven build and features to account for that. Verified by
running full maven build including packaging.

Update bazel build files to account for that. Verified by a
clean-slate bazel build :all, followed by running the JSchSshTest
and the ApacheSshTest via bazel.

Change-Id: Ia084942f4425b454529de148e00417e7da786a90
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

By default sshd will use its default built-in list, which matches
the one of openssh (as far as the algorithms exist in sshd at all).
But it doesn't handle HostKeyAlgorithms from the ssh config at all.

Implement this as in openssh, including the '+' and '-' modifiers
and reordering the default if there are known host keys for a
server already.

Add tests for the reordering.

Also use a more robust reader for the known hosts file. The default
aborts on the first error.

Bug: 520927
Change-Id: Ib1684440bfe2e96140536aa1a93c4bd4a0d35916
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

sshd does support gssapi-with-mic on the server side, but has no
built-in client-side support for this authentication mechanism.

Add our own implementation for it, following RFC 4462.[1] To avoid
needlessly re-trying mechanisms that aren't even configured on the
client, we disable mechanisms that fail on the very first attempt
to use them.

Since we have no real Kerberos5 test setup, this cannot be fully
tested in CI. The disabling of the authentication mechanism and
that it is skipped when not successful _is_ tested.

[1] https://www.ietf.org/rfc/rfc4462.txt

Bug: 520927
Change-Id: I5d0cdb14103588a57c52f927df541b589ab88d88
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Add support for git-receive-pack to the ssh git server and add two
new tests for pushing.

This actually uncovered an undocumented requirement in TransportSftp:
the FTP rename operation assumes POSIX semantics, i.e., that the
target is removed. This works as written only for servers that
support and advertise the "posix-rename@openssh.com" FTP extension.

Our little Apache MINA server does not advertise this extension.

Fix the FtpChannel implementation for Jsch to handle this case in a
meaningful way so that it can pass the new "push over sftp" test.

Add more tests to test the behavior of server host key checking.

Also refactor the tests generally to separate better the test
framework from the actual tests.

Bug: 520927
Change-Id: Ia4bb85e17ddacde7b36ee8c2d5d454bbfa66dfc3
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Add a simple ssh git server based on Apache MINA sshd, and use it
in new tests that verify ssh operations and in particular a number
of bugs that had cropped up over time in JSch.

The git server supports fetching only, and sftp access.

The tests are all in an abstract base class; the concrete JschSshTest
class only provides ssh-specific test setup. So the same tests could
be run easily also with some other ssh client.

Bug: 520927
Change-Id: Ide6687b717fb497a29fc83f22b07390a26dfce1d
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>