sockets: implement WithAdditionalUsersAndGroups for windows

[thaJeztah]

• depends on / stacked on sockets: make NewUnixSocket, WithChown, WithChmod unix-only #138

---

• Implement a WithAdditionalUsersAndGroups (windows daemon allows
  specifying multiple additional users and groups for named pipes
  and unix-sockets).
• Implement NewUnixSocket that accepts (optional) additional users
  and groups.

Partially based on https://github.com/moby/moby/blob/6b45c76a233b1b8b56465f76c21c09fd7920e82d/daemon/listeners/listeners_windows.go#L53-L80

- Description for the changelog

- A picture of a cute animal (not mandatory but encouraged)

[thaJeztah]

Looks like the tests were skipped on Windows;

--- PASS: TestInmemSocket (0.00s)
=== RUN   TestUnixSocketWithOpts
--- PASS: TestUnixSocketWithOpts (0.00s)
=== RUN   TestNewUnixSocket
    unix_socket_windows_test.go:20: requires root
--- SKIP: TestNewUnixSocket (0.00s)
=== RUN   TestNewUnixSocketUnknownGroup
    unix_socket_windows_test.go:36: requires root
--- SKIP: TestNewUnixSocketUnknownGroup (0.00s)
PASS
ok  	github.com/docker/go-connections/sockets	0.026s
=== RUN   TestConfigServerTLSFailsIfUnableToLoadCerts

[thaJeztah]

=== RUN   TestNewUnixSocket
    unix_socket_windows_test.go:32: listen unix /tmp/test.sock: bind: A socket operation encountered a dead network.

[thaJeztah]

"Progress" previously we got;

=== RUN   TestNewUnixSocket
    unix_socket_windows_test.go:32: listen unix /tmp/test.sock: bind: A socket operation encountered a dead network.

I changed the fixed /tmp/test.sock to use os.TempDir(), and now I get;

=== RUN   TestNewUnixSocket
    unix_socket_windows_test.go:88: The parameter is incorrect.

Possibly the path is too long? Or must it use unix conventions (/somewhere/foo.sock), and not a Windows file path (C:\somewhere\foo.sock)?

[thaJeztah]

UGH back to the drawing board; some digging (to be verified) that unix sockets on Windows are always virtual, so there's no file, and no permissions to set. So there's no option to control access?

[thaJeztah]

Hm... so AI was dreaming that up; https://devblogs.microsoft.com/commandline/af_unix-comes-to-windows/

Unix sockets provide a mechanism for secure communication. Communication over unix sockets can be secured by controlling the file (or directory) permissions on the pathname sockets (or the parent directory). For example, the bind socket API creates a ‘socket’ file with the given pathname. The creation of the new socket file will fail if the calling process does not has write permission on the directory where the file is being created. Similarly, for connecting to a stream socket, the connecting process should have write permission on the socket. The same level of security is available and enforced on the Windows unix socket implementation. See the man page on AF_UNIX for more details on the security.

[austinvazquez]

From debugging, if we are not specifying an owner then we should exclude OWNER_SECURITY_INFORMATION from security information here.

The thing I was unsure is if this is additive or do we need to apply the owner/group from the security descriptor?

[austinvazquez]

*group