Add the constant, and implement hashing of known host names in
OpenSshServerKeyDatabase. Add a test verifying that the hashing
works.

Bug: 548492
Change-Id: Iabe82b666da627bd7f4d82519a366d166aa9ddd4
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Provide a wrapper interface and change the implementation such that
a client can substitute its own database of known hosts keys instead
of the default file-based mechanism.

Bug: 547619
Change-Id: Ifc25a4519fa5bcf7bb8541b9f3e2de15215e3d66
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Reduce the dependency on the ClientSession in preparation to
remove it altogether. Remove the internal helper, re-implement
the needed bits. We have not implemented any configuration
possibility in JGit for creating hashed host names in known hosts
files, so we don't need the sshd code that theoretically would
enable this.

Change-Id: I295f5106b60e1cc3a9d085b0cb7ff747daae88be
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

We're actually interested only in the known public keys, we don't need
the corresponding host entry from the config.

Change-Id: Ibde6dffe9e3f87bfbb7c70d1f733b2b0e28cad71
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>

Change-Id: Ie44950f7d2f2f94a0412efb6c274f6e1e31efcd6
Signed-off-by: Carsten Hammer <carsten.hammer@t-online.de>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

Change-Id: I143c242c0e3299323ae166a59947b1195539e6bf
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>

Change-Id: I0fdf595cba93f5a5cdd0496cee07ac91db304532
Signed-off-by: Mincong Huang <mincong.h@gmail.com>

We will get an API evolution problem if we expose as API classes and
interfaces that derive from upstream classes or interfaces. Upstream
interfaces also evolve quite erratically and evolution doesn't seem
to follow semantic versioning.

Introduce a new KeyPasswordProvider interface so that we don't have
to depend on the upstream FilePasswordProvider in our API. (We do
need _some_ abstraction for getting passwords for encrypted keys in
the API; EGit will need to provide its own implementation.)

Move some other upstream dependencies (HostConfigEntry, and various
previously protected methods in SshdSessionFactory) out of the API:
classes moved to internal space, and methods made private.

The only dependencies on upstream interfaces are thus in a few method
parameter types. Those cannot be avoided, but should also not pose
problems.

Bug: 520927
Change-Id: Idc9c6b0f237f29f46343c0fe15179242f2007bec
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>

Add a new ssh client implementation based on Apach MINA sshd 2.0.0.

This implementation uses JGit's own config file parser and host entry
resolver. Code inspection of the Apache MINA implementation revealed
a few bugs or idiosyncrasies that immediately would re-introduce bugs
already fixed in the past in JGit.

Apache MINA sshd is not without quirks either, and I had to configure
and override more than I had expected. But at least it was all doable
in clean ways.

Apache MINA boasts support for Bouncy Castle, so in theory this should
open the way to using more ssh key algorithms, such as ed25519.

The implementation is in a separate bundle and is still not used in
the core org.eclipse.jgit bundle. The tests re-use the ssh tests from
the core test bundle.

Bug: 520927
Change-Id: Ib35e73c35799140fe050d1ff4fb18d0d3596580e
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>