Mercurial > hg
view mercurial/hgweb/common.py @ 35984:cdc93fe1da77
wireprotoserver: move protocol parsing and dispatch out of hgweb
Previously, hgweb_mod had code for detecting if the request
was for the wire protocol. It would then (eventually) call
wireprotoserver.callhttp() to dispatch the request handling.
Detection of wire protocol requests is not trivial. There's
currently a big gotcha in the handling of the "cmd" request
parameter, for example.
Furthermore, in the near future we will have a second HTTP
protocol handler. Its mechanism for calling commands will be
a bit different. And we don't want the low-level logic for
detecting protocol commands to live in hgweb.
We establish a new function in wireprotoserver for detecting
an HTTP protocol request and for giving the caller an easy-to-use
mechanism for dispatching requests to it.
Some wire protocol specific functionality still lives in hgweb.
This will be addressed in subsequent commits.
Differential Revision: https://phab.mercurial-scm.org/D2019
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Wed, 31 Jan 2018 16:21:43 -0800 |
parents | 6ef744a7df65 |
children | d18c0cf5f3ab |
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line source
# hgweb/common.py - Utility functions needed by hgweb_mod and hgwebdir_mod # # Copyright 21 May 2005 - (c) 2005 Jake Edge <jake@edge2.net> # 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 base64 import errno import mimetypes import os from .. import ( encoding, pycompat, util, ) httpserver = util.httpserver HTTP_OK = 200 HTTP_NOT_MODIFIED = 304 HTTP_BAD_REQUEST = 400 HTTP_UNAUTHORIZED = 401 HTTP_FORBIDDEN = 403 HTTP_NOT_FOUND = 404 HTTP_METHOD_NOT_ALLOWED = 405 HTTP_SERVER_ERROR = 500 def ismember(ui, username, userlist): """Check if username is a member of userlist. If userlist has a single '*' member, all users are considered members. Can be overridden by extensions to provide more complex authorization schemes. """ return userlist == ['*'] or username in userlist def checkauthz(hgweb, req, op): '''Check permission for operation based on request data (including authentication info). Return if op allowed, else raise an ErrorResponse exception.''' user = req.env.get('REMOTE_USER') deny_read = hgweb.configlist('web', 'deny_read') if deny_read and (not user or ismember(hgweb.repo.ui, user, deny_read)): raise ErrorResponse(HTTP_UNAUTHORIZED, 'read not authorized') allow_read = hgweb.configlist('web', 'allow_read') if allow_read and (not ismember(hgweb.repo.ui, user, allow_read)): raise ErrorResponse(HTTP_UNAUTHORIZED, 'read not authorized') if op == 'pull' and not hgweb.allowpull: raise ErrorResponse(HTTP_UNAUTHORIZED, 'pull not authorized') elif op == 'pull' or op is None: # op is None for interface requests return # enforce that you can only push using POST requests if req.env['REQUEST_METHOD'] != 'POST': msg = 'push requires POST request' raise ErrorResponse(HTTP_METHOD_NOT_ALLOWED, msg) # require ssl by default for pushing, auth info cannot be sniffed # and replayed scheme = req.env.get('wsgi.url_scheme') if hgweb.configbool('web', 'push_ssl') and scheme != 'https': raise ErrorResponse(HTTP_FORBIDDEN, 'ssl required') deny = hgweb.configlist('web', 'deny_push') if deny and (not user or ismember(hgweb.repo.ui, user, deny)): raise ErrorResponse(HTTP_UNAUTHORIZED, 'push not authorized') allow = hgweb.configlist('web', 'allow-push') if not (allow and ismember(hgweb.repo.ui, user, allow)): raise ErrorResponse(HTTP_UNAUTHORIZED, 'push not authorized') # Hooks for hgweb permission checks; extensions can add hooks here. # Each hook is invoked like this: hook(hgweb, request, operation), # where operation is either read, pull or push. Hooks should either # raise an ErrorResponse exception, or just return. # # It is possible to do both authentication and authorization through # this. permhooks = [checkauthz] class ErrorResponse(Exception): def __init__(self, code, message=None, headers=None): if message is None: message = _statusmessage(code) Exception.__init__(self, message) self.code = code if headers is None: headers = [] self.headers = headers class continuereader(object): def __init__(self, f, write): self.f = f self._write = write self.continued = False def read(self, amt=-1): if not self.continued: self.continued = True self._write('HTTP/1.1 100 Continue\r\n\r\n') return self.f.read(amt) def __getattr__(self, attr): if attr in ('close', 'readline', 'readlines', '__iter__'): return getattr(self.f, attr) raise AttributeError def _statusmessage(code): responses = httpserver.basehttprequesthandler.responses return responses.get(code, ('Error', 'Unknown error'))[0] def statusmessage(code, message=None): return '%d %s' % (code, message or _statusmessage(code)) def get_stat(spath, fn): """stat fn if it exists, spath otherwise""" cl_path = os.path.join(spath, fn) if os.path.exists(cl_path): return os.stat(cl_path) else: return os.stat(spath) def get_mtime(spath): return get_stat(spath, "00changelog.i").st_mtime def ispathsafe(path): """Determine if a path is safe to use for filesystem access.""" parts = path.split('/') for part in parts: if (part in ('', os.curdir, os.pardir) or pycompat.ossep in part or pycompat.osaltsep is not None and pycompat.osaltsep in part): return False return True def staticfile(directory, fname, req): """return a file inside directory with guessed Content-Type header fname always uses '/' as directory separator and isn't allowed to contain unusual path components. Content-Type is guessed using the mimetypes module. Return an empty string if fname is illegal or file not found. """ if not ispathsafe(fname): return fpath = os.path.join(*fname.split('/')) if isinstance(directory, str): directory = [directory] for d in directory: path = os.path.join(d, fpath) if os.path.exists(path): break try: os.stat(path) ct = mimetypes.guess_type(pycompat.fsdecode(path))[0] or "text/plain" with open(path, 'rb') as fh: data = fh.read() req.respond(HTTP_OK, ct, body=data) except TypeError: raise ErrorResponse(HTTP_SERVER_ERROR, 'illegal filename') except OSError as err: if err.errno == errno.ENOENT: raise ErrorResponse(HTTP_NOT_FOUND) else: raise ErrorResponse(HTTP_SERVER_ERROR, encoding.strtolocal(err.strerror)) def paritygen(stripecount, offset=0): """count parity of horizontal stripes for easier reading""" if stripecount and offset: # account for offset, e.g. due to building the list in reverse count = (stripecount + offset) % stripecount parity = (stripecount + offset) / stripecount & 1 else: count = 0 parity = 0 while True: yield parity count += 1 if stripecount and count >= stripecount: parity = 1 - parity count = 0 def get_contact(config): """Return repo contact information or empty string. web.contact is the primary source, but if that is not set, try ui.username or $EMAIL as a fallback to display something useful. """ return (config("web", "contact") or config("ui", "username") or encoding.environ.get("EMAIL") or "") def caching(web, req): tag = r'W/"%d"' % web.mtime if req.env.get('HTTP_IF_NONE_MATCH') == tag: raise ErrorResponse(HTTP_NOT_MODIFIED) req.headers.append(('ETag', tag)) def cspvalues(ui): """Obtain the Content-Security-Policy header and nonce value. Returns a 2-tuple of the CSP header value and the nonce value. First value is ``None`` if CSP isn't enabled. Second value is ``None`` if CSP isn't enabled or if the CSP header doesn't need a nonce. """ # Without demandimport, "import uuid" could have an immediate side-effect # running "ldconfig" on Linux trying to find libuuid. # With Python <= 2.7.12, that "ldconfig" is run via a shell and the shell # may pollute the terminal with: # # shell-init: error retrieving current directory: getcwd: cannot access # parent directories: No such file or directory # # Python >= 2.7.13 has fixed it by running "ldconfig" directly without a # shell (hg changeset a09ae70f3489). # # Moved "import uuid" from here so it's executed after we know we have # a sane cwd (i.e. after dispatch.py cwd check). # # We can move it back once we no longer need Python <= 2.7.12 support. import uuid # Don't allow untrusted CSP setting since it be disable protections # from a trusted/global source. csp = ui.config('web', 'csp', untrusted=False) nonce = None if csp and '%nonce%' in csp: nonce = base64.urlsafe_b64encode(uuid.uuid4().bytes).rstrip('=') csp = csp.replace('%nonce%', nonce) return csp, nonce