view tests/sshprotoext.py @ 37766:925707ac2855

lfs: add the 'Authorization' property to the Batch API response, if present

The client copies all of these properties under 'header' to the HTTP Headers of
the subsequent GET or PUT request that it performs.  That allows the Basic HTTP
authentication used to authorize the Batch API request to also authorize the
upload/download action.

There's likely further work to do here.  There's an 'authenticated' boolean key
in the Batch API response that can be set, and there is an 'LFS-Authenticate'
header that is used instead of 'WWW-Authenticate'[1].  (We likely need to
support both, since some hosting solutions are likely to only respond with the
latter.)  In any event, this works with SCM Manager, so there is real world
benefit.

I'm limiting the headers returned to 'Basic', because that's all the lfs spec
calls out.  In practice, I've seen gitbucket emit custom header content[2].

[1] https://github.com/git-lfs/git-lfs/blob/master/docs/api/batch.md#response-errors
[2] https://github.com/gitbucket/gitbucket/blob/35655f33c7713f08515ed640ece0948acd6d6168/src/main/scala/gitbucket/core/servlet/GitRepositoryServlet.scala#L119

# sshprotoext.py - Extension to test behavior of SSH protocol
#
# Copyright 2018 Gregory Szorc <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

# This extension replaces the SSH server started via `hg serve --stdio`.
# The server behaves differently depending on environment variables.

from __future__ import absolute_import

from mercurial import (
    error,
    extensions,
    registrar,
    sshpeer,
    wireproto,
    wireprotoserver,
)

configtable = {}
configitem = registrar.configitem(configtable)

configitem(b'sshpeer', b'mode', default=None)
configitem(b'sshpeer', b'handshake-mode', default=None)

class bannerserver(wireprotoserver.sshserver):
    """Server that sends a banner to stdout."""
    def serve_forever(self):
        for i in range(10):
            self._fout.write(b'banner: line %d\n' % i)

        super(bannerserver, self).serve_forever()

class prehelloserver(wireprotoserver.sshserver):
    """Tests behavior when connecting to <0.9.1 servers.

    The ``hello`` wire protocol command was introduced in Mercurial
    0.9.1. Modern clients send the ``hello`` command when connecting
    to SSH servers. This mock server tests behavior of the handshake
    when ``hello`` is not supported.
    """
    def serve_forever(self):
        l = self._fin.readline()
        assert l == b'hello\n'
        # Respond to unknown commands with an empty reply.
        wireprotoserver._sshv1respondbytes(self._fout, b'')
        l = self._fin.readline()
        assert l == b'between\n'
        proto = wireprotoserver.sshv1protocolhandler(self._ui, self._fin,
                                                     self._fout)
        rsp = wireproto.dispatch(self._repo, proto, b'between')
        wireprotoserver._sshv1respondbytes(self._fout, rsp.data)

        super(prehelloserver, self).serve_forever()

def performhandshake(orig, ui, stdin, stdout, stderr):
    """Wrapped version of sshpeer._performhandshake to send extra commands."""
    mode = ui.config(b'sshpeer', b'handshake-mode')
    if mode == b'pre-no-args':
        ui.debug(b'sending no-args command\n')
        stdin.write(b'no-args\n')
        stdin.flush()
        return orig(ui, stdin, stdout, stderr)
    elif mode == b'pre-multiple-no-args':
        ui.debug(b'sending unknown1 command\n')
        stdin.write(b'unknown1\n')
        ui.debug(b'sending unknown2 command\n')
        stdin.write(b'unknown2\n')
        ui.debug(b'sending unknown3 command\n')
        stdin.write(b'unknown3\n')
        stdin.flush()
        return orig(ui, stdin, stdout, stderr)
    else:
        raise error.ProgrammingError(b'unknown HANDSHAKECOMMANDMODE: %s' %
                                     mode)

def extsetup(ui):
    # It's easier for tests to define the server behavior via environment
    # variables than config options. This is because `hg serve --stdio`
    # has to be invoked with a certain form for security reasons and
    # `dummyssh` can't just add `--config` flags to the command line.
    servermode = ui.environ.get(b'SSHSERVERMODE')

    if servermode == b'banner':
        wireprotoserver.sshserver = bannerserver
    elif servermode == b'no-hello':
        wireprotoserver.sshserver = prehelloserver
    elif servermode:
        raise error.ProgrammingError(b'unknown server mode: %s' % servermode)

    peermode = ui.config(b'sshpeer', b'mode')

    if peermode == b'extra-handshake-commands':
        extensions.wrapfunction(sshpeer, '_performhandshake', performhandshake)
    elif peermode:
        raise error.ProgrammingError(b'unknown peer mode: %s' % peermode)