Fix thread-safety issues in gitlab-shell

Closes #518

See merge request gitlab-org/gitlab-shell!462

Replace cleanup functions with t.Cleanup

See merge request gitlab-org/gitlab-shell!460

In this case we don't need to propagate cleanup
function. It simplifies the code.

gitlab-sshd: Acceptance test for the discover command

See merge request gitlab-org/gitlab-shell!457

With this, we can start to build confidence in making changes to
gitlab-sshd.

chore: Move environment introspection to sshenv module

See merge request gitlab-org/gitlab-shell!451

Refactors introspection of execution environment to rely on
per-connection state (`gitlab-shell`) or per request (`gitlab-sshd`)

Relates to https://gitlab.com/gitlab-org/gitlab-shell/-/issues/496

Clarify which versions of Go we support

See merge request gitlab-org/gitlab-shell!459

Compile against go 1.14-1.16

See merge request gitlab-org/gitlab-shell!458

Use Docker 20.10.3 instead of 19.03.0 on build

Closes #512

See merge request gitlab-org/gitlab-shell!456

Signed-off-by: Takuya Noguchi <takninnovationresearch@gmail.com>

Release v13.17.0

See merge request gitlab-org/gitlab-shell!455

Fix gitlab-shell panic when log file not writable

See merge request gitlab-org/gitlab-shell!453

Previously when the gitlab-shell log was not writable, gitlab-shell
would attempt to fall back to the syslog to log an error. However,
if the syslog logger creation succeeded, gitlab-shell would panic
since `err` was `nil`.

Relates to https://gitlab.com/gitlab-org/gitlab-shell/-/issues/510

Resolve "Intermittent test failure in TestUploadPack"

See merge request gitlab-org/gitlab-shell!452

Add monitoring endpoint to sshd

See merge request gitlab-org/gitlab-shell!449

* Counter for how many times the max concurrent sessions limit was hit.
* Histogram for duration of each SSH connection.

https://gitlab.com/gitlab-org/gitlab-shell/-/issues/121



Signed-off-by: Ben Kochie <superq@gmail.com>

Add a basic monitoring endpoint to the sshd command.
* Listen on localhost port 9122 by default.
* Integrate build/version info.
* Update example config.

https://gitlab.com/gitlab-org/gitlab-shell/-/issues/121



Signed-off-by: Ben Kochie <superq@gmail.com>

Refactor Config defaults

See merge request gitlab-org/gitlab-shell!450

Use "omitempty" to allow defaults in the config file to be correctly
passed. Without this, explicitly setting an empty default like an empty
string will not work. Needed in order to allow explicitly disabling some
settings.

Related to: https://gitlab.com/gitlab-org/gitlab-shell/-/issues/121



Signed-off-by: Ben Kochie <superq@gmail.com>

Update Go modules

See merge request gitlab-org/gitlab-shell!448

Some pre-work for adding Prometheus metrics to SSH server.
* Update Go modules to latest.
* Add Go 1.15 build.

https://gitlab.com/gitlab-org/gitlab-shell/-/issues/121



Signed-off-by: Ben Kochie <superq@gmail.com>

Read limited input for yes answer

See merge request gitlab-org/security/gitlab-shell!1

Release v13.16.0

See merge request gitlab-org/gitlab-shell!446

Merge branch '504-remove-the-session-duration-information-from-the-output-of-2fa_verify-command' into 'main'

Resolve "Remove the session duration information from the output of `2fa_verify` command"

See merge request gitlab-org/gitlab-shell!445

This change removes session duration
information from output of 2fa_verify command

Add gitlab-sshd to .gitignore

See merge request gitlab-org/gitlab-shell!444

RFC: Simple built-in SSH server

Closes #165

See merge request gitlab-org/gitlab-shell!394

Remove default branch statement in docs

Closes #489

See merge request gitlab-org/gitlab-shell!443

Now `master` is removed, this is no longer needed