Make all transports request protocol V2 when fetching. Depending on
the transport, set the GIT_PROTOCOL environment variable (file and
ssh), pass the Git-Protocol header (http), or set the hidden
"\0version=2\0" (git anon). We'll fall back to V0 if the server
doesn't reply with a version 2 answer.

A user can control which protocol the client requests via the git
config protocol.version; if not set, JGit requests protocol V2 for
fetching. Pushing always uses protocol V0 still.

In the API, there is only a new Transport.openFetch() version that
takes a collection of RefSpecs plus additional patterns to construct
the Ref prefixes for the "ls-refs" command in protocol V2. If none
are given, the server will still advertise all refs, even in protocol
V2.

BasePackConnection.readAdvertisedRefs() handles falling back to
protocol V0. It newly returns true if V0 was used and the advertised
refs were read, and false if V2 is used and an explicit "ls-refs" is
needed. (This can't be done transparently inside readAdvertisedRefs()
because a "stateless RPC" transport like TransportHttp may need to
open a new connection for writing.)

BasePackFetchConnection implements the changes needed for the protocol
V2 "fetch" command (simplified ACK handling, delimiters, section
headers).

In TransportHttp, change readSmartHeaders() to also recognize the
"version 2" packet line as a valid smart server indication.

Adapt tests, and run all the HTTP tests not only with both HTTP
connection factories (JDK and Apache HttpClient) but also with both
protocol V0 and V2. Do the same for the SSH transport tests.

Bug: 553083
Change-Id: Ice9866aa78020f5ca8f397cde84dc224bf5d41b4
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

This is useful to access git repositories behind a bastion server
(jump host).

Add a constant for the config; rewrite the whole connection initiation
to parse the value and (recursively) set up the chain of hops. Add
tests for a single hop and two different ways to configure a two-hop
chain.

The connection timeout applies to each hop in the chain individually.

Change-Id: Idd25af95aa2ec5367404587e4e530b0663c03665
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Close the channel gracefully to give the server a chance to clean up
properly on its side.

Bug: 565854
Change-Id: Iedda5af3b97c8321f08f7ce854274cbb30e401de
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

The timeout on RemoteSession.exec() cannot be a timeout for the
whole command. It can only be a timeout for setting up the process;
after that it's the application's responsibility to implement some
timeout for the execution of the command, for instance by calling
Process.waitFor(int, TimeUnit) or through other means.

Sessions returned by an SshSessionFactory are already connected and
authenticated -- they must be, because RemoteSession offers no
operations for connecting or authenticating a session.

Change the implementation of SshdExecProcess.waitFor() to wait
indefinitely. The original implementation used the timeout from
RemoteSession.exec() because of that erroneous javadoc.

Change-Id: I3c7ede24ab66d4c81f72d178ce5012d383cd826e
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>

Since [1] the gerrit project includes jgit as a submodule, and has this
warning enabled, resulting in 100s of warnings in the console.

Also enable the warning here, and fix them.

At the same time, add missing braces around adjacent and nearby one-line
blocks.

[1] https://gerrit-review.googlesource.com/c/gerrit/+/227897

Change-Id: I81df3fc7ed6eedf6874ce1a3bedfa727a1897e4c
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>

Change-Id: I1a9112e6a4f938638c599b489cb0858eca27ab91
Signed-off-by: Carsten Hammer <carsten.hammer@t-online.de>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

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>