##// END OF EJS Templates
subrepo: set GIT_ALLOW_PROTOCOL to limit git clone protocols (SEC)...
subrepo: set GIT_ALLOW_PROTOCOL to limit git clone protocols (SEC) CVE-2016-3068 (1/1) Git's git-remote-ext remote helper provides an ext:: URL scheme that allows running arbitrary shell commands. This feature allows implementing simple git smart transports with a single shell shell command. However, git submodules could clone arbitrary URLs specified in the .gitmodules file. This was reported as CVE-2015-7545 and fixed in git v2.6.1. However, if a user directly clones a malicious ext URL, the git client will still run arbitrary shell commands. Mercurial is similarly effected. Mercurial allows specifying git repositories as subrepositories. Git ext:: URLs can be specified as Mercurial subrepositories allowing arbitrary shell commands to be run on `hg clone ...`. The Mercurial community would like to thank Blake Burkhart for reporting this issue. The description of the issue is copied from Blake's report. This commit changes submodules to pass the GIT_ALLOW_PROTOCOL env variable to git commands with the same list of allowed protocols that git submodule is using. When the GIT_ALLOW_PROTOCOL env variable is already set, we just pass it to git without modifications.

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sshpeer.py
347 lines | 10.6 KiB | text/x-python | PythonLexer
# sshpeer.py - ssh repository proxy class for mercurial
#
# Copyright 2005, 2006 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.
from __future__ import absolute_import
import re
from .i18n import _
from . import (
error,
util,
wireproto,
)
class remotelock(object):
def __init__(self, repo):
self.repo = repo
def release(self):
self.repo.unlock()
self.repo = None
def __enter__(self):
return self
def __exit__(self, exc_type, exc_val, exc_tb):
if self.repo:
self.release()
def __del__(self):
if self.repo:
self.release()
def _serverquote(s):
if not s:
return s
'''quote a string for the remote shell ... which we assume is sh'''
if re.match('[a-zA-Z0-9@%_+=:,./-]*$', s):
return s
return "'%s'" % s.replace("'", "'\\''")
def _forwardoutput(ui, pipe):
"""display all data currently available on pipe as remote output.
This is non blocking."""
s = util.readpipe(pipe)
if s:
for l in s.splitlines():
ui.status(_("remote: "), l, '\n')
class doublepipe(object):
"""Operate a side-channel pipe in addition of a main one
The side-channel pipe contains server output to be forwarded to the user
input. The double pipe will behave as the "main" pipe, but will ensure the
content of the "side" pipe is properly processed while we wait for blocking
call on the "main" pipe.
If large amounts of data are read from "main", the forward will cease after
the first bytes start to appear. This simplifies the implementation
without affecting actual output of sshpeer too much as we rarely issue
large read for data not yet emitted by the server.
The main pipe is expected to be a 'bufferedinputpipe' from the util module
that handle all the os specific bites. This class lives in this module
because it focus on behavior specific to the ssh protocol."""
def __init__(self, ui, main, side):
self._ui = ui
self._main = main
self._side = side
def _wait(self):
"""wait until some data are available on main or side
return a pair of boolean (ismainready, issideready)
(This will only wait for data if the setup is supported by `util.poll`)
"""
if getattr(self._main, 'hasbuffer', False): # getattr for classic pipe
return (True, True) # main has data, assume side is worth poking at.
fds = [self._main.fileno(), self._side.fileno()]
try:
act = util.poll(fds)
except NotImplementedError:
# non supported yet case, assume all have data.
act = fds
return (self._main.fileno() in act, self._side.fileno() in act)
def write(self, data):
return self._call('write', data)
def read(self, size):
return self._call('read', size)
def readline(self):
return self._call('readline')
def _call(self, methname, data=None):
"""call <methname> on "main", forward output of "side" while blocking
"""
# data can be '' or 0
if (data is not None and not data) or self._main.closed:
_forwardoutput(self._ui, self._side)
return ''
while True:
mainready, sideready = self._wait()
if sideready:
_forwardoutput(self._ui, self._side)
if mainready:
meth = getattr(self._main, methname)
if data is None:
return meth()
else:
return meth(data)
def close(self):
return self._main.close()
def flush(self):
return self._main.flush()
class sshpeer(wireproto.wirepeer):
def __init__(self, ui, path, create=False):
self._url = path
self.ui = ui
self.pipeo = self.pipei = self.pipee = None
u = util.url(path, parsequery=False, parsefragment=False)
if u.scheme != 'ssh' or not u.host or u.path is None:
self._abort(error.RepoError(_("couldn't parse location %s") % path))
self.user = u.user
if u.passwd is not None:
self._abort(error.RepoError(_("password in URL not supported")))
self.host = u.host
self.port = u.port
self.path = u.path or "."
sshcmd = self.ui.config("ui", "ssh", "ssh")
remotecmd = self.ui.config("ui", "remotecmd", "hg")
args = util.sshargs(sshcmd,
_serverquote(self.host),
_serverquote(self.user),
_serverquote(self.port))
if create:
cmd = '%s %s %s' % (sshcmd, args,
util.shellquote("%s init %s" %
(_serverquote(remotecmd), _serverquote(self.path))))
ui.debug('running %s\n' % cmd)
res = ui.system(cmd)
if res != 0:
self._abort(error.RepoError(_("could not create remote repo")))
self._validaterepo(sshcmd, args, remotecmd)
def url(self):
return self._url
def _validaterepo(self, sshcmd, args, remotecmd):
# cleanup up previous run
self.cleanup()
cmd = '%s %s %s' % (sshcmd, args,
util.shellquote("%s -R %s serve --stdio" %
(_serverquote(remotecmd), _serverquote(self.path))))
self.ui.debug('running %s\n' % cmd)
cmd = util.quotecommand(cmd)
# while self.subprocess isn't used, having it allows the subprocess to
# to clean up correctly later
#
# no buffer allow the use of 'select'
# feel free to remove buffering and select usage when we ultimately
# move to threading.
sub = util.popen4(cmd, bufsize=0)
self.pipeo, self.pipei, self.pipee, self.subprocess = sub
self.pipei = util.bufferedinputpipe(self.pipei)
self.pipei = doublepipe(self.ui, self.pipei, self.pipee)
self.pipeo = doublepipe(self.ui, self.pipeo, self.pipee)
# skip any noise generated by remote shell
self._callstream("hello")
r = self._callstream("between", pairs=("%s-%s" % ("0"*40, "0"*40)))
lines = ["", "dummy"]
max_noise = 500
while lines[-1] and max_noise:
l = r.readline()
self.readerr()
if lines[-1] == "1\n" and l == "\n":
break
if l:
self.ui.debug("remote: ", l)
lines.append(l)
max_noise -= 1
else:
self._abort(error.RepoError(_('no suitable response from '
'remote hg')))
self._caps = set()
for l in reversed(lines):
if l.startswith("capabilities:"):
self._caps.update(l[:-1].split(":")[1].split())
break
def _capabilities(self):
return self._caps
def readerr(self):
_forwardoutput(self.ui, self.pipee)
def _abort(self, exception):
self.cleanup()
raise exception
def cleanup(self):
if self.pipeo is None:
return
self.pipeo.close()
self.pipei.close()
try:
# read the error descriptor until EOF
for l in self.pipee:
self.ui.status(_("remote: "), l)
except (IOError, ValueError):
pass
self.pipee.close()
__del__ = cleanup
def _callstream(self, cmd, **args):
self.ui.debug("sending %s command\n" % cmd)
self.pipeo.write("%s\n" % cmd)
_func, names = wireproto.commands[cmd]
keys = names.split()
wireargs = {}
for k in keys:
if k == '*':
wireargs['*'] = args
break
else:
wireargs[k] = args[k]
del args[k]
for k, v in sorted(wireargs.iteritems()):
self.pipeo.write("%s %d\n" % (k, len(v)))
if isinstance(v, dict):
for dk, dv in v.iteritems():
self.pipeo.write("%s %d\n" % (dk, len(dv)))
self.pipeo.write(dv)
else:
self.pipeo.write(v)
self.pipeo.flush()
return self.pipei
def _callcompressable(self, cmd, **args):
return self._callstream(cmd, **args)
def _call(self, cmd, **args):
self._callstream(cmd, **args)
return self._recv()
def _callpush(self, cmd, fp, **args):
r = self._call(cmd, **args)
if r:
return '', r
while True:
d = fp.read(4096)
if not d:
break
self._send(d)
self._send("", flush=True)
r = self._recv()
if r:
return '', r
return self._recv(), ''
def _calltwowaystream(self, cmd, fp, **args):
r = self._call(cmd, **args)
if r:
# XXX needs to be made better
raise error.Abort('unexpected remote reply: %s' % r)
while True:
d = fp.read(4096)
if not d:
break
self._send(d)
self._send("", flush=True)
return self.pipei
def _recv(self):
l = self.pipei.readline()
if l == '\n':
self.readerr()
msg = _('check previous remote output')
self._abort(error.OutOfBandError(hint=msg))
self.readerr()
try:
l = int(l)
except ValueError:
self._abort(error.ResponseError(_("unexpected response:"), l))
return self.pipei.read(l)
def _send(self, data, flush=False):
self.pipeo.write("%d\n" % len(data))
if data:
self.pipeo.write(data)
if flush:
self.pipeo.flush()
self.readerr()
def lock(self):
self._call("lock")
return remotelock(self)
def unlock(self):
self._call("unlock")
def addchangegroup(self, cg, source, url, lock=None):
'''Send a changegroup to the remote server. Return an integer
similar to unbundle(). DEPRECATED, since it requires locking the
remote.'''
d = self._call("addchangegroup")
if d:
self._abort(error.RepoError(_("push refused: %s") % d))
while True:
d = cg.read(4096)
if not d:
break
self.pipeo.write(d)
self.readerr()
self.pipeo.flush()
self.readerr()
r = self._recv()
if not r:
return 1
try:
return int(r)
except ValueError:
self._abort(error.ResponseError(_("unexpected response:"), r))
instance = sshpeer