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
#
# mercurial - scalable distributed SCM
#
# Copyright 2005-2007 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

import os
import sys

if os.environ.get('HGUNICODEPEDANTRY', False):
    try:
        reload(sys)
        sys.setdefaultencoding("undefined")
    except NameError:
        pass

libdir = '@LIBDIR@'

if libdir != '@' 'LIBDIR' '@':
    if not os.path.isabs(libdir):
        libdir = os.path.join(os.path.dirname(os.path.realpath(__file__)),
                              libdir)
        libdir = os.path.abspath(libdir)
    sys.path.insert(0, libdir)

# enable importing on demand to reduce startup time
try:
    if sys.version_info[0] < 3:
        from mercurial import demandimport; demandimport.enable()
except ImportError:
    sys.stderr.write("abort: couldn't find mercurial libraries in [%s]\n" %
                     ' '.join(sys.path))
    sys.stderr.write("(check your install and PYTHONPATH)\n")
    sys.exit(-1)

import mercurial.util
import mercurial.dispatch

for fp in (sys.stdin, sys.stdout, sys.stderr):
    mercurial.util.setbinary(fp)

mercurial.dispatch.run()