dispatch: protect against malicious 'hg serve --stdio' invocations (sec)
Some shared-ssh installations assume that 'hg serve --stdio' is a safe
command to run for minimally trusted users. Unfortunately, the messy
implementation of argument parsing here meant that trying to access a
repo named '--debugger' would give the user a pdb prompt, thereby
sidestepping any hoped-for sandboxing. Serving repositories over HTTP(S)
is unaffected.
We're not currently hardening any subcommands other than 'serve'. If
your service exposes other commands to users with arbitrary repository
names, it is imperative that you defend against repository names of
'--debugger' and anything starting with '--config'.
The read-only mode of hg-ssh stopped working because it provided its hook
configuration to "hg serve --stdio" via --config parameter. This is banned for
security reasons now. This patch switches it to directly call ui.setconfig().
If your custom hosting infrastructure relies on passing --config to
"hg serve --stdio", you'll need to find a different way to get that configuration
into Mercurial, either by using ui.setconfig() as hg-ssh does in this patch,
or by placing an hgrc file someplace where Mercurial will read it.
mitrandir@fb.com provided some extra fixes for the dispatch code and
for hg-ssh in places that I overlooked.
#!/usr/bin/env python
from __future__ import absolute_import
"""
Small and dumb HTTP server for use in tests.
"""
import optparse
import signal
import sys
from mercurial import (
server,
util,
)
httpserver = util.httpserver
OptionParser = optparse.OptionParser
class simplehttpservice(object):
def __init__(self, host, port):
self.address = (host, port)
def init(self):
self.httpd = httpserver.httpserver(
self.address, httpserver.simplehttprequesthandler)
def run(self):
self.httpd.serve_forever()
if __name__ == '__main__':
parser = OptionParser()
parser.add_option('-p', '--port', dest='port', type='int', default=8000,
help='TCP port to listen on', metavar='PORT')
parser.add_option('-H', '--host', dest='host', default='localhost',
help='hostname or IP to listen on', metavar='HOST')
parser.add_option('--pid', dest='pid',
help='file name where the PID of the server is stored')
parser.add_option('-f', '--foreground', dest='foreground',
action='store_true',
help='do not start the HTTP server in the background')
parser.add_option('--daemon-postexec', action='append')
(options, args) = parser.parse_args()
signal.signal(signal.SIGTERM, lambda x, y: sys.exit(0))
if options.foreground and options.pid:
parser.error("options --pid and --foreground are mutually exclusive")
opts = {'pid_file': options.pid,
'daemon': not options.foreground,
'daemon_postexec': options.daemon_postexec}
service = simplehttpservice(options.host, options.port)
server.runservice(opts, initfn=service.init, runfn=service.run,
runargs=[sys.executable, __file__] + sys.argv[1:])