sslutil: document and slightly refactor validation logic
This main purpose of this patch is to make it clearer that fingerprint
pinning takes precedence over CA verification. This will make
subsequent refactoring to the validation code easier to read.
# hgweb/server.py - The standalone hg web server.
#
# Copyright 21 May 2005 - (c) 2005 Jake Edge <jake@edge2.net>
# 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.
from __future__ import absolute_import
import BaseHTTPServer
import SocketServer
import errno
import os
import socket
import sys
import traceback
import urllib
from ..i18n import _
from .. import (
error,
util,
)
from . import (
common,
)
def _splitURI(uri):
"""Return path and query that has been split from uri
Just like CGI environment, the path is unquoted, the query is
not.
"""
if '?' in uri:
path, query = uri.split('?', 1)
else:
path, query = uri, ''
return urllib.unquote(path), query
class _error_logger(object):
def __init__(self, handler):
self.handler = handler
def flush(self):
pass
def write(self, str):
self.writelines(str.split('\n'))
def writelines(self, seq):
for msg in seq:
self.handler.log_error("HG error: %s", msg)
class _httprequesthandler(BaseHTTPServer.BaseHTTPRequestHandler):
url_scheme = 'http'
@staticmethod
def preparehttpserver(httpserver, ssl_cert):
"""Prepare .socket of new HTTPServer instance"""
pass
def __init__(self, *args, **kargs):
self.protocol_version = 'HTTP/1.1'
BaseHTTPServer.BaseHTTPRequestHandler.__init__(self, *args, **kargs)
def _log_any(self, fp, format, *args):
fp.write("%s - - [%s] %s\n" % (self.client_address[0],
self.log_date_time_string(),
format % args))
fp.flush()
def log_error(self, format, *args):
self._log_any(self.server.errorlog, format, *args)
def log_message(self, format, *args):
self._log_any(self.server.accesslog, format, *args)
def log_request(self, code='-', size='-'):
xheaders = []
if util.safehasattr(self, 'headers'):
xheaders = [h for h in self.headers.items()
if h[0].startswith('x-')]
self.log_message('"%s" %s %s%s',
self.requestline, str(code), str(size),
''.join([' %s:%s' % h for h in sorted(xheaders)]))
def do_write(self):
try:
self.do_hgweb()
except socket.error as inst:
if inst[0] != errno.EPIPE:
raise
def do_POST(self):
try:
self.do_write()
except Exception:
self._start_response("500 Internal Server Error", [])
self._write("Internal Server Error")
self._done()
tb = "".join(traceback.format_exception(*sys.exc_info()))
self.log_error("Exception happened during processing "
"request '%s':\n%s", self.path, tb)
def do_GET(self):
self.do_POST()
def do_hgweb(self):
path, query = _splitURI(self.path)
env = {}
env['GATEWAY_INTERFACE'] = 'CGI/1.1'
env['REQUEST_METHOD'] = self.command
env['SERVER_NAME'] = self.server.server_name
env['SERVER_PORT'] = str(self.server.server_port)
env['REQUEST_URI'] = self.path
env['SCRIPT_NAME'] = self.server.prefix
env['PATH_INFO'] = path[len(self.server.prefix):]
env['REMOTE_HOST'] = self.client_address[0]
env['REMOTE_ADDR'] = self.client_address[0]
if query:
env['QUERY_STRING'] = query
if self.headers.typeheader is None:
env['CONTENT_TYPE'] = self.headers.type
else:
env['CONTENT_TYPE'] = self.headers.typeheader
length = self.headers.getheader('content-length')
if length:
env['CONTENT_LENGTH'] = length
for header in [h for h in self.headers.keys()
if h not in ('content-type', 'content-length')]:
hkey = 'HTTP_' + header.replace('-', '_').upper()
hval = self.headers.getheader(header)
hval = hval.replace('\n', '').strip()
if hval:
env[hkey] = hval
env['SERVER_PROTOCOL'] = self.request_version
env['wsgi.version'] = (1, 0)
env['wsgi.url_scheme'] = self.url_scheme
if env.get('HTTP_EXPECT', '').lower() == '100-continue':
self.rfile = common.continuereader(self.rfile, self.wfile.write)
env['wsgi.input'] = self.rfile
env['wsgi.errors'] = _error_logger(self)
env['wsgi.multithread'] = isinstance(self.server,
SocketServer.ThreadingMixIn)
env['wsgi.multiprocess'] = isinstance(self.server,
SocketServer.ForkingMixIn)
env['wsgi.run_once'] = 0
self.saved_status = None
self.saved_headers = []
self.sent_headers = False
self.length = None
self._chunked = None
for chunk in self.server.application(env, self._start_response):
self._write(chunk)
if not self.sent_headers:
self.send_headers()
self._done()
def send_headers(self):
if not self.saved_status:
raise AssertionError("Sending headers before "
"start_response() called")
saved_status = self.saved_status.split(None, 1)
saved_status[0] = int(saved_status[0])
self.send_response(*saved_status)
self.length = None
self._chunked = False
for h in self.saved_headers:
self.send_header(*h)
if h[0].lower() == 'content-length':
self.length = int(h[1])
if (self.length is None and
saved_status[0] != common.HTTP_NOT_MODIFIED):
self._chunked = (not self.close_connection and
self.request_version == "HTTP/1.1")
if self._chunked:
self.send_header('Transfer-Encoding', 'chunked')
else:
self.send_header('Connection', 'close')
self.end_headers()
self.sent_headers = True
def _start_response(self, http_status, headers, exc_info=None):
code, msg = http_status.split(None, 1)
code = int(code)
self.saved_status = http_status
bad_headers = ('connection', 'transfer-encoding')
self.saved_headers = [h for h in headers
if h[0].lower() not in bad_headers]
return self._write
def _write(self, data):
if not self.saved_status:
raise AssertionError("data written before start_response() called")
elif not self.sent_headers:
self.send_headers()
if self.length is not None:
if len(data) > self.length:
raise AssertionError("Content-length header sent, but more "
"bytes than specified are being written.")
self.length = self.length - len(data)
elif self._chunked and data:
data = '%x\r\n%s\r\n' % (len(data), data)
self.wfile.write(data)
self.wfile.flush()
def _done(self):
if self._chunked:
self.wfile.write('0\r\n\r\n')
self.wfile.flush()
class _httprequesthandlerssl(_httprequesthandler):
"""HTTPS handler based on Python's ssl module"""
url_scheme = 'https'
@staticmethod
def preparehttpserver(httpserver, ssl_cert):
try:
import ssl
ssl.wrap_socket
except ImportError:
raise error.Abort(_("SSL support is unavailable"))
httpserver.socket = ssl.wrap_socket(
httpserver.socket, server_side=True,
certfile=ssl_cert, ssl_version=ssl.PROTOCOL_TLSv1)
def setup(self):
self.connection = self.request
self.rfile = socket._fileobject(self.request, "rb", self.rbufsize)
self.wfile = socket._fileobject(self.request, "wb", self.wbufsize)
try:
import threading
threading.activeCount() # silence pyflakes and bypass demandimport
_mixin = SocketServer.ThreadingMixIn
except ImportError:
if util.safehasattr(os, "fork"):
_mixin = SocketServer.ForkingMixIn
else:
class _mixin(object):
pass
def openlog(opt, default):
if opt and opt != '-':
return open(opt, 'a')
return default
class MercurialHTTPServer(object, _mixin, BaseHTTPServer.HTTPServer):
# SO_REUSEADDR has broken semantics on windows
if os.name == 'nt':
allow_reuse_address = 0
def __init__(self, ui, app, addr, handler, **kwargs):
BaseHTTPServer.HTTPServer.__init__(self, addr, handler, **kwargs)
self.daemon_threads = True
self.application = app
handler.preparehttpserver(self, ui.config('web', 'certificate'))
prefix = ui.config('web', 'prefix', '')
if prefix:
prefix = '/' + prefix.strip('/')
self.prefix = prefix
alog = openlog(ui.config('web', 'accesslog', '-'), sys.stdout)
elog = openlog(ui.config('web', 'errorlog', '-'), sys.stderr)
self.accesslog = alog
self.errorlog = elog
self.addr, self.port = self.socket.getsockname()[0:2]
self.fqaddr = socket.getfqdn(addr[0])
class IPv6HTTPServer(MercurialHTTPServer):
address_family = getattr(socket, 'AF_INET6', None)
def __init__(self, *args, **kwargs):
if self.address_family is None:
raise error.RepoError(_('IPv6 is not available on this system'))
super(IPv6HTTPServer, self).__init__(*args, **kwargs)
def create_server(ui, app):
if ui.config('web', 'certificate'):
handler = _httprequesthandlerssl
else:
handler = _httprequesthandler
if ui.configbool('web', 'ipv6'):
cls = IPv6HTTPServer
else:
cls = MercurialHTTPServer
# ugly hack due to python issue5853 (for threaded use)
try:
import mimetypes
mimetypes.init()
except UnicodeDecodeError:
# Python 2.x's mimetypes module attempts to decode strings
# from Windows' ANSI APIs as ascii (fail), then re-encode them
# as ascii (clown fail), because the default Python Unicode
# codec is hardcoded as ascii.
sys.argv # unwrap demand-loader so that reload() works
reload(sys) # resurrect sys.setdefaultencoding()
oldenc = sys.getdefaultencoding()
sys.setdefaultencoding("latin1") # or any full 8-bit encoding
mimetypes.init()
sys.setdefaultencoding(oldenc)
address = ui.config('web', 'address', '')
port = util.getport(ui.config('web', 'port', 8000))
try:
return cls(ui, app, (address, port), handler)
except socket.error as inst:
raise error.Abort(_("cannot start server at '%s:%d': %s")
% (address, port, inst.args[1]))