Source code for mechanize._urllib2_fork

"""Fork of urllib2.

When reading this, don't assume that all code in here is reachable.  Code in
the rest of mechanize may be used instead.

Copyright (c) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 Python
Software Foundation; All Rights Reserved

Copyright 2002-2009 John J Lee <jjl@pobox.com>

This code is free software; you can redistribute it and/or modify it
under the terms of the BSD or ZPL 2.1 licenses (see the file
LICENSE included with the distribution).

"""

# XXX issues:
# If an authentication error handler that tries to perform
# authentication for some reason but fails, how should the error be
# signalled?  The client needs to know the HTTP error code.  But if
# the handler knows that the problem was, e.g., that it didn't know
# that hash algo that requested in the challenge, it would be good to
# pass that information along to the client, too.
# ftp errors aren't handled cleanly
# check digest against correct (i.e. non-apache) implementation

# Possible extensions:
# complex proxies  XXX not sure what exactly was meant by this
# abstract factory for opener

from __future__ import absolute_import

import base64
import bisect
import copy
import hashlib
import logging
import os
import platform
import posixpath
import re
import socket
import sys
import time
from collections import OrderedDict
from functools import partial
from io import BufferedReader, BytesIO

from . import _rfc3986
from ._clientcookie import CookieJar
from ._headersutil import normalize_header_name
from ._response import closeable_response
from .polyglot import (HTTPConnection, HTTPError, HTTPSConnection, URLError,
                       as_unicode, create_response_info, ftpwrapper,
                       getproxies, is_class, is_mapping, is_py2, is_string,
                       iteritems, map, raise_with_traceback, splitattr,
                       splitpasswd, splitport, splittype, splituser,
                       splitvalue, unquote, unwrap, url2pathname,
                       urllib_proxy_bypass, urllib_splithost, urlparse,
                       urlsplit, urlunparse)


def sha1_digest(data):
    if not isinstance(data, bytes):
        data = data.encode('utf-8')
    return hashlib.sha1(data).hexdigest()


def md5_digest(data):
    if not isinstance(data, bytes):
        data = data.encode('utf-8')
    return hashlib.md5(data).hexdigest()


if platform.python_implementation() == 'PyPy':
    def create_readline_wrapper(fh):
        fh.recv = fh.read
        if is_py2:
            if not hasattr(fh, '_drop'):
                fh._drop = lambda: None
                fh._reuse = lambda: None
            ans = socket._fileobject(fh, close=True)
        else:
            fh.recv_into = fh.readinto
            fh._decref_socketios = lambda: None
            ans = BufferedReader(socket.SocketIO(fh, 'r'))
        return ans
else:
    def create_readline_wrapper(fh):
        fh.recv = fh.read
        if is_py2:
            ans = socket._fileobject(fh, close=True)
        else:
            fh.recv_into = fh.readinto
            fh._decref_socketios = lambda: None
            ans = BufferedReader(socket.SocketIO(fh, 'r'))
        return ans


splithost = urllib_splithost


# used in User-Agent header sent
__version__ = sys.version[:3]

_opener = None


def urlopen(url, data=None):
    global _opener
    if _opener is None:
        _opener = build_opener()
    return _opener._open(url, data)


def install_opener(opener):
    global _opener
    _opener = opener


# copied from cookielib.py
_cut_port_re = re.compile(r":\d+$")


def request_host(request):
    """Return request-host, as defined by RFC 2965.

    Variation from RFC: returned value is lowercased, for convenient
    comparison.

    """
    url = request.get_full_url()
    host = urlparse(url)[1]
    if host == "":
        host = request.get_header("Host", "")

    # remove port, if present
    host = _cut_port_re.sub("", host, 1)
    return host.lower()


PERCENT_RE = re.compile(b"%[a-fA-F0-9]{2}")
ZONE_ID_CHARS = set(bytearray(
    b"ABCDEFGHIJKLMNOPQRSTUVWXYZ" b"abcdefghijklmnopqrstuvwxyz" b"0123456789._!-"
))
USERINFO_CHARS = ZONE_ID_CHARS | set(bytearray(b"$&'()*+,;=:"))
PATH_CHARS = USERINFO_CHARS | set(bytearray(b'@/~'))
QUERY_CHARS = FRAGMENT_CHARS = PATH_CHARS | {ord(b"?")}


def fix_invalid_bytes_in_url_component(component, allowed_chars=PATH_CHARS):
    if not component:
        return component
    is_bytes = isinstance(component, bytes)
    if not is_bytes:
        component = component.encode('utf-8', 'surrogatepass')
    percent_encodings = PERCENT_RE.findall(component)
    for enc in percent_encodings:
        if not enc.isupper():
            component = component.replace(enc, enc.upper())
    is_percent_encoded = len(percent_encodings) == component.count(b"%")
    encoded_component = bytearray()
    percent = ord('%')
    for byte_ord in bytearray(component):
        if (is_percent_encoded and byte_ord == percent) or (byte_ord < 128 and byte_ord in allowed_chars):
            encoded_component.append(byte_ord)
            continue
        encoded_component.extend(b"%" + (hex(byte_ord)[2:].encode().zfill(2).upper()))
    encoded_component = bytes(encoded_component)
    if not is_bytes:
        encoded_component = encoded_component.decode('utf-8')
    return encoded_component


def normalize_url(url):
    parsed = urlparse(url)
    netloc = parsed.netloc
    if not isinstance(netloc, bytes) and netloc:
        def safe_encode(label):
            try:
                return label.encode('idna').decode('ascii')
            except ValueError:
                return label.encode('ascii', 'replace').decode('ascii')
        netloc = u'.'.join(map(safe_encode, netloc.split(u'.')))

    return urlunparse(parsed._replace(
        path=fix_invalid_bytes_in_url_component(parsed.path), netloc=netloc,
        query=fix_invalid_bytes_in_url_component(parsed.query, QUERY_CHARS),
        fragment=fix_invalid_bytes_in_url_component(parsed.fragment, FRAGMENT_CHARS),
    ))


class Request:

    def __init__(self, url, data=None, headers={},
                 origin_req_host=None, unverifiable=False, method=None):
        # unwrap('<URL:type://host/path>') --> 'type://host/path'
        self.__original = normalize_url(unwrap(url))
        self.type = None
        self._method = method and str(method)
        # self.__r_type is what's left after doing the splittype
        self.host = None
        self.port = None
        self._tunnel_host = None
        self.data = data
        self.headers = OrderedDict()
        for key, value in iteritems(headers):
            self.add_header(key, value)
        self.unredirected_hdrs = OrderedDict()
        if origin_req_host is None:
            origin_req_host = request_host(self)
        self.origin_req_host = origin_req_host
        self.unverifiable = unverifiable
        try:
            self.get_host()  # in py3 cookiejar expect self.host to be not None
        except Exception:
            self.host = None

    def __getattr__(self, attr):
        # XXX this is a fallback mechanism to guard against these
        # methods getting called in a non-standard order.  this may be
        # too complicated and/or unnecessary.
        # XXX should the __r_XXX attributes be public?
        if attr[:12] == '_Request__r_':
            name = attr[12:]
            if hasattr(Request, 'get_' + name):
                getattr(self, 'get_' + name)()
                return getattr(self, attr)
        raise AttributeError(attr)

[docs] def get_method(self): ' The method used for HTTP requests ' if self._method is None: return "POST" if self.has_data() else 'GET' return self._method
# XXX these helper methods are lame
[docs] def set_data(self, data): ' Set the data (a bytestring) to be sent with this request ' self.data = data
add_data = set_data
[docs] def has_data(self): ' True iff there is some data to be sent with this request ' return self.data is not None
[docs] def get_data(self): ' The data to be sent with this request ' return self.data
def get_full_url(self): return self.__original @property def full_url(self): # In python 3 this is a deleteable and settable property, which when # deleted gets set to None. But this interface does not seem to be used # by any stdlib code, so this should be sufficient. return self.__original def get_type(self): if self.type is None: self.type, self.__r_type = splittype(self.__original) if self.type is None: raise ValueError("unknown url type: %s" % self.__original) return self.type def get_host(self): if self.host is None: self.host, self.__r_host = splithost(self.__r_type) if self.host: self.host = unquote(self.host) return self.host def get_selector(self): scheme, authority, path, query, fragment = _rfc3986.urlsplit( self.__r_host) if path == "": path = "/" # RFC 2616, section 3.2.2 fragment = None # RFC 3986, section 3.5 return _rfc3986.urlunsplit([scheme, authority, path, query, fragment]) def set_proxy(self, host, type): orig_host = self.get_host() if self.get_type() == 'https' and not self._tunnel_host: self._tunnel_host = orig_host else: self.type = type self.__r_host = self.__original self.host = host
[docs] def has_proxy(self): """Private method.""" # has non-HTTPS proxy return self.__r_host == self.__original
def get_origin_req_host(self): return self.origin_req_host def is_unverifiable(self): return self.unverifiable
[docs] def add_header(self, key, val=None): ''' Add the specified header, replacing existing one, if needed. If val is None, remove the header. ''' # useful for something like authentication key = normalize_header_name(key) if val is None: self.headers.pop(key, None) else: self.headers[key] = val
[docs] def add_unredirected_header(self, key, val): ''' Same as :meth:`add_header()` except that this header will not be sent for redirected requests. ''' key = normalize_header_name(key) if val is None: self.unredirected_hdrs.pop(key, None) else: self.unredirected_hdrs[key] = val
[docs] def has_header(self, header_name): ''' Check if the specified header is present ''' header_name = normalize_header_name(header_name) return (header_name in self.headers or header_name in self.unredirected_hdrs)
[docs] def get_header(self, header_name, default=None): ''' Get the value of the specified header. If absent, return `default` ''' header_name = normalize_header_name(header_name) return self.headers.get( header_name, self.unredirected_hdrs.get(header_name, default))
[docs] def header_items(self): ''' Get a copy of all headers for this request as a list of 2-tuples ''' hdrs = self.unredirected_hdrs.copy() hdrs.update(self.headers) return list(iteritems(hdrs))
class OpenerDirector(object): def __init__(self): client_version = "Python-urllib/%s" % __version__ self.addheaders = [('User-agent', client_version)] self.finalize_request_headers = None # manage the individual handlers self.handlers = [] self.handle_open = {} self.handle_error = {} self.process_response = {} self.process_request = {} def add_handler(self, handler): if not hasattr(handler, "add_parent"): raise TypeError("expected BaseHandler instance, got %r" % type(handler)) added = False for meth in dir(handler): if meth in ["redirect_request", "do_open", "proxy_open"]: # oops, coincidental match continue i = meth.find("_") protocol = meth[:i] condition = meth[i + 1:] if condition.startswith("error"): j = condition.find("_") + i + 1 kind = meth[j + 1:] try: kind = int(kind) except ValueError: pass lookup = self.handle_error.get(protocol, {}) self.handle_error[protocol] = lookup elif condition == "open": kind = protocol lookup = self.handle_open elif condition == "response": kind = protocol lookup = self.process_response elif condition == "request": kind = protocol lookup = self.process_request else: continue handlers = lookup.setdefault(kind, []) if handlers: bisect.insort(handlers, handler) else: handlers.append(handler) added = True if added: # the handlers must work in an specific order, the order # is specified in a Handler attribute bisect.insort(self.handlers, handler) handler.add_parent(self) def close(self): # Only exists for backwards compatibility. pass def _call_chain(self, chain, kind, meth_name, *args): # Handlers raise an exception if no one else should try to handle # the request, or return None if they can't but another handler # could. Otherwise, they return the response. handlers = chain.get(kind, ()) for handler in handlers: func = getattr(handler, meth_name) result = func(*args) if result is not None: return result def _open(self, req, data=None): result = self._call_chain(self.handle_open, 'default', 'default_open', req) if result: return result protocol = req.get_type() result = self._call_chain(self.handle_open, protocol, protocol + '_open', req) if result: return result return self._call_chain(self.handle_open, 'unknown', 'unknown_open', req) def error(self, proto, *args): if proto in ('http', 'https'): # XXX http[s] protocols are special-cased # https is not different than http dict = self.handle_error['http'] proto = args[2] # YUCK! meth_name = 'http_error_%s' % proto http_err = 1 orig_args = args else: dict = self.handle_error meth_name = proto + '_error' http_err = 0 args = (dict, proto, meth_name) + args result = self._call_chain(*args) if result: return result if http_err: args = (dict, 'default', 'http_error_default') + orig_args return self._call_chain(*args) # XXX probably also want an abstract factory that knows when it makes # sense to skip a superclass in favor of a subclass and when it might # make sense to include both def build_opener(*handlers): """Create an opener object from a list of handlers. The opener will use several default handlers, including support for HTTP, FTP and when applicable, HTTPS. If any of the handlers passed as arguments are subclasses of the default handlers, the default handlers will not be used. """ opener = OpenerDirector() default_classes = [ProxyHandler, UnknownHandler, HTTPHandler, HTTPDefaultErrorHandler, HTTPRedirectHandler, FTPHandler, FileHandler, HTTPErrorProcessor] default_classes.append(HTTPSHandler) skip = set() for klass in default_classes: for check in handlers: if is_class(check): if issubclass(check, klass): skip.add(klass) elif isinstance(check, klass): skip.add(klass) for klass in skip: default_classes.remove(klass) for klass in default_classes: opener.add_handler(klass()) for h in handlers: if is_class(h): h = h() opener.add_handler(h) return opener class BaseHandler: handler_order = 500 def add_parent(self, parent): self.parent = parent def close(self): # Only exists for backwards compatibility pass def __lt__(self, other): return self.handler_order < getattr( other, 'handler_order', sys.maxsize) def __copy__(self): return self.__class__() class HTTPErrorProcessor(BaseHandler): """Process HTTP error responses. The purpose of this handler is to to allow other response processors a look-in by removing the call to parent.error() from AbstractHTTPHandler. For non-2xx error codes, this just passes the job on to the Handler.<proto>_error_<code> methods, via the OpenerDirector.error method. Eventually, HTTPDefaultErrorHandler will raise an HTTPError if no other handler handles the error. """ handler_order = 1000 # after all other processors def http_response(self, request, response): code, msg, hdrs = response.code, response.msg, response.info() # According to RFC 2616, "2xx" code indicates that the client's # request was successfully received, understood, and accepted. if not (200 <= code < 300): # hardcoded http is NOT a bug response = self.parent.error( 'http', request, response, code, msg, hdrs) return response https_response = http_response class HTTPDefaultErrorHandler(BaseHandler): def http_error_default(self, req, fp, code, msg, hdrs): # why these error methods took the code, msg, headers args in the first # place rather than a response object, I don't know, but to avoid # multiple wrapping, we're discarding them if isinstance(fp, HTTPError): response = fp else: response = HTTPError( req.get_full_url(), code, msg, hdrs, fp) assert code == response.code assert msg == response.msg assert hdrs == response.hdrs raise response class HTTPRedirectHandler(BaseHandler): # maximum number of redirections to any single URL # this is needed because of the state that cookies introduce max_repeats = 4 # maximum total number of redirections (regardless of URL) before # assuming we're in a loop max_redirections = 10 # Implementation notes: # To avoid the server sending us into an infinite loop, the request # object needs to track what URLs we have already seen. Do this by # adding a handler-specific attribute to the Request object. The value # of the dict is used to count the number of times the same URL has # been visited. This is needed because visiting the same URL twice # does not necessarily imply a loop, thanks to state introduced by # cookies. # Always unhandled redirection codes: # 300 Multiple Choices: should not handle this here. # 304 Not Modified: no need to handle here: only of interest to caches # that do conditional GETs # 305 Use Proxy: probably not worth dealing with here # 306 Unused: what was this for in the previous versions of protocol?? def redirect_request(self, req, fp, code, msg, headers, newurl): """Return a Request or None in response to a redirect. This is called by the http_error_30x methods when a redirection response is received. If a redirection should take place, return a new Request to allow http_error_30x to perform the redirect. Otherwise, raise HTTPError if no-one else should try to handle this url. Return None if you can't but another Handler might. """ from ._request import Request m = req.get_method() if (code in (301, 302, 303, 307, 308, "refresh") and m in ("GET", "HEAD") or code in (301, 302, 303, 307, 308, "refresh") and m == "POST"): # Strictly (according to RFC 2616), 301 or 302 in response # to a POST MUST NOT cause a redirection without confirmation # from the user (of urllib2, in this case). In practice, # essentially all clients do redirect in this case, so we do # the same. # TODO: really refresh redirections should be visiting; tricky to # fix new = Request( newurl, headers=req.headers, origin_req_host=req.get_origin_req_host(), unverifiable=True, visit=False, method=m if code in (307, 308) else None, timeout=req.timeout) new._origin_req = getattr(req, "_origin_req", req) return new else: raise HTTPError(req.get_full_url(), code, msg, headers, fp) def http_error_302(self, req, fp, code, msg, headers): # Some servers (incorrectly) return multiple Location headers # (so probably same goes for URI). Use first header. if 'location' in headers: newurl = headers.getheaders('location')[0] elif 'uri' in headers: newurl = headers.getheaders('uri')[0] else: return newurl = _rfc3986.clean_url(newurl) newurl = _rfc3986.urljoin(req.get_full_url(), newurl) # XXX Probably want to forget about the state of the current # request, although that might interact poorly with other # handlers that also use handler-specific request attributes new = self.redirect_request(req, fp, code, msg, headers, newurl) if new is None: return # loop detection # .redirect_dict has a key url if url was previously visited. if hasattr(req, 'redirect_dict'): visited = new.redirect_dict = req.redirect_dict if (visited.get(newurl, 0) >= self.max_repeats or len(visited) >= self.max_redirections): raise HTTPError(req.get_full_url(), code, self.inf_msg + msg, headers, fp) else: visited = new.redirect_dict = req.redirect_dict = {} visited[newurl] = visited.get(newurl, 0) + 1 # Don't close the fp until we are sure that we won't use it # with HTTPError. fp.read() fp.close() return self.parent.open(new) http_error_301 = http_error_303 = http_error_307 = http_error_302 http_error_refresh = http_error_308 = http_error_302 inf_msg = "The HTTP server returned a redirect error that would " \ "lead to an infinite loop.\n" \ "The last 30x error message was:\n" def _parse_proxy(proxy): """Return (scheme, user, password, host/port) given a URL or an authority. If a URL is supplied, it must have an authority (host:port) component. According to RFC 3986, having an authority component means the URL must have two slashes after the scheme: >>> _parse_proxy('file:/ftp.example.com/') Traceback (most recent call last): ValueError: proxy URL with no authority: 'file:/ftp.example.com/' The first three items of the returned tuple may be None. Examples of authority parsing: >>> _parse_proxy('proxy.example.com') (None, None, None, 'proxy.example.com') >>> _parse_proxy('proxy.example.com:3128') (None, None, None, 'proxy.example.com:3128') The authority component may optionally include userinfo (assumed to be username:password): >>> _parse_proxy('joe:password@proxy.example.com') (None, 'joe', 'password', 'proxy.example.com') >>> _parse_proxy('joe:password@proxy.example.com:3128') (None, 'joe', 'password', 'proxy.example.com:3128') Same examples, but with URLs instead: >>> _parse_proxy('http://proxy.example.com/') ('http', None, None, 'proxy.example.com') >>> _parse_proxy('http://proxy.example.com:3128/') ('http', None, None, 'proxy.example.com:3128') >>> _parse_proxy('http://joe:password@proxy.example.com/') ('http', 'joe', 'password', 'proxy.example.com') >>> _parse_proxy('http://joe:password@proxy.example.com:3128') ('http', 'joe', 'password', 'proxy.example.com:3128') Everything after the authority is ignored: >>> _parse_proxy('ftp://joe:password@proxy.example.com/rubbish:3128') ('ftp', 'joe', 'password', 'proxy.example.com') Test for no trailing '/' case: >>> _parse_proxy('http://joe:password@proxy.example.com') ('http', 'joe', 'password', 'proxy.example.com') """ scheme, r_scheme = splittype(proxy) if not r_scheme.startswith("/"): # authority scheme = None authority = proxy else: # URL if not r_scheme.startswith("//"): raise ValueError("proxy URL with no authority: %r" % proxy) # We have an authority, so for RFC 3986-compliant URLs (by ss 3. # and 3.3.), path is empty or starts with '/' end = r_scheme.find("/", 2) if end == -1: end = None authority = r_scheme[2:end] userinfo, hostport = splituser(authority) if userinfo is not None: user, password = splitpasswd(userinfo) else: user = password = None return scheme, user, password, hostport class ProxyHandler(BaseHandler): # Proxies must be in front handler_order = 100 def __init__(self, proxies=None, proxy_bypass=None): if proxies is None: proxies = getproxies() assert is_mapping(proxies), "proxies must be a mapping" self.proxies = proxies for type, url in iteritems(proxies): setattr(self, '%s_open' % type, lambda r, proxy=url, type=type, meth=self.proxy_open: meth(r, proxy, type)) if proxy_bypass is None: proxy_bypass = urllib_proxy_bypass self._proxy_bypass = proxy_bypass def proxy_open(self, req, proxy, type): orig_type = req.get_type() proxy_type, user, password, hostport = _parse_proxy(proxy) if proxy_type is None: proxy_type = orig_type if req.get_host() and self._proxy_bypass(req.get_host()): return None if user and password: user_pass = '%s:%s' % (unquote(user), unquote(password)) if not isinstance(user_pass, bytes): user_pass = user_pass.encode('utf-8') creds = base64.b64encode(user_pass).strip() if isinstance(creds, bytes): creds = creds.decode('ascii') req.add_header('Proxy-authorization', 'Basic ' + creds) hostport = unquote(hostport) req.set_proxy(hostport, proxy_type) if orig_type == proxy_type or orig_type == 'https': # let other handlers take care of it return None else: # need to start over, because the other handlers don't # grok the proxy's URL type # e.g. if we have a constructor arg proxies like so: # {'http': 'ftp://proxy.example.com'}, we may end up turning # a request for http://acme.example.com/a into one for # ftp://proxy.example.com/a return self.parent.open(req) def __copy__(self): return ProxyHandler(self.proxies.copy(), self._proxy_bypass) class HTTPPasswordMgr: def __init__(self): self.passwd = {} def add_password(self, realm, uri, user, passwd): # uri could be a single URI or a sequence if is_string(uri): uri = [uri] if realm not in self.passwd: self.passwd[realm] = {} for default_port in True, False: reduced_uri = tuple( [self.reduce_uri(u, default_port) for u in uri]) self.passwd[realm][reduced_uri] = (user, passwd) def find_user_password(self, realm, authuri): domains = self.passwd.get(realm, {}) for default_port in True, False: reduced_authuri = self.reduce_uri(authuri, default_port) for uris, authinfo in iteritems(domains): for uri in uris: if self.is_suburi(uri, reduced_authuri): return authinfo return None, None def reduce_uri(self, uri, default_port=True): """Accept authority or URI and extract only the authority and path.""" # note HTTP URLs do not have a userinfo component parts = urlsplit(uri) if parts[1]: # URI scheme = parts[0] authority = parts[1] path = parts[2] or '/' else: # host or host:port scheme = None authority = uri path = '/' host, port = splitport(authority) if default_port and port is None and scheme is not None: dport = {"http": 80, "https": 443, }.get(scheme) if dport is not None: authority = "%s:%d" % (host, dport) return authority, path def is_suburi(self, base, test): """Check if test is below base in a URI tree Both args must be URIs in reduced form. """ if base == test: return True if base[0] != test[0]: return False common = posixpath.commonprefix((base[1], test[1])) if len(common) == len(base[1]): return True return False def __copy__(self): ans = self.__class__() ans.passwd = copy.deepcopy(self.passwd) return ans class HTTPPasswordMgrWithDefaultRealm(HTTPPasswordMgr): def find_user_password(self, realm, authuri): user, password = HTTPPasswordMgr.find_user_password(self, realm, authuri) if user is not None: return user, password return HTTPPasswordMgr.find_user_password(self, None, authuri) class AbstractBasicAuthHandler: # XXX this allows for multiple auth-schemes, but will stupidly pick # the last one with a realm specified. # allow for double- and single-quoted realm values # (single quotes are a violation of the RFC, but appear in the wild) rx = re.compile('(?:^|,)' # start of the string or ',' '[ \t]*' # optional whitespaces '([^ \t,]+)' # scheme like "Basic" '[ \t]+' # mandatory whitespaces # realm=xxx # realm='xxx' # realm="xxx" 'realm=(["\']?)([^"\']*)\\2', re.I) # XXX could pre-emptively send auth info already accepted (RFC 2617, # end of section 2, and section 1.2 immediately after "credentials" # production). def __init__(self, password_mgr=None): if password_mgr is None: password_mgr = HTTPPasswordMgr() self.passwd = password_mgr self.add_password = self.passwd.add_password def http_error_auth_reqed(self, authreq, host, req, headers): # host may be an authority (without userinfo) or a URL with an # authority # XXX could be multiple headers authreq = headers.get(authreq, None) if authreq: mo = AbstractBasicAuthHandler.rx.search(authreq) if mo: scheme, quote, realm = mo.groups() if scheme.lower() == 'basic': return self.retry_http_basic_auth(host, req, realm) def retry_http_basic_auth(self, host, req, realm): user, pw = self.passwd.find_user_password(realm, host) if pw is not None: raw = "%s:%s" % (user, pw) auth = str('Basic %s' % base64.b64encode( raw.encode('utf-8')).strip().decode('ascii')) if req.get_header(self.auth_header, None) == auth: return None newreq = copy.copy(req) newreq.add_header(self.auth_header, auth) newreq.visit = False return self.parent.open(newreq) else: return None def __copy__(self): return self.__class__(self.passwd.__copy__()) class HTTPBasicAuthHandler(AbstractBasicAuthHandler, BaseHandler): auth_header = 'Authorization' def http_error_401(self, req, fp, code, msg, headers): url = req.get_full_url() return self.http_error_auth_reqed('www-authenticate', url, req, headers) def __copy__(self): return AbstractBasicAuthHandler.__copy__(self) class ProxyBasicAuthHandler(AbstractBasicAuthHandler, BaseHandler): auth_header = 'Proxy-authorization' def http_error_407(self, req, fp, code, msg, headers): # http_error_auth_reqed requires that there is no userinfo component in # authority. Assume there isn't one, since urllib2 does not (and # should not, RFC 3986 s. 3.2.1) support requests for URLs containing # userinfo. authority = req.get_host() return self.http_error_auth_reqed('proxy-authenticate', authority, req, headers) def __copy__(self): return AbstractBasicAuthHandler.__copy__(self) randombytes = os.urandom class AbstractDigestAuthHandler: # Digest authentication is specified in RFC 2617. # XXX The client does not inspect the Authentication-Info header # in a successful response. # XXX It should be possible to test this implementation against # a mock server that just generates a static set of challenges. # XXX qop="auth-int" supports is shaky def __init__(self, passwd=None): if passwd is None: passwd = HTTPPasswordMgr() self.passwd = passwd self.add_password = self.passwd.add_password self.retried = 0 self.nonce_count = 0 self.last_nonce = None def reset_retry_count(self): self.retried = 0 def http_error_auth_reqed(self, auth_header, host, req, headers): authreq = headers.get(auth_header, None) if self.retried > 5: # Don't fail endlessly - if we failed once, we'll probably # fail a second time. Hm. Unless the Password Manager is # prompting for the information. Crap. This isn't great # but it's better than the current 'repeat until recursion # depth exceeded' approach <wink> raise HTTPError(req.get_full_url(), 401, "digest auth failed", headers, None) else: self.retried += 1 if authreq: scheme = authreq.split()[0] if scheme.lower() == 'digest': return self.retry_http_digest_auth(req, authreq) def retry_http_digest_auth(self, req, auth): token, challenge = auth.split(' ', 1) chal = parse_keqv_list(parse_http_list(challenge)) auth = self.get_authorization(req, chal) if auth: auth_val = 'Digest %s' % auth if req.get_header(self.auth_header, None) == auth_val: return None newreq = copy.copy(req) newreq.add_unredirected_header(self.auth_header, auth_val) newreq.visit = False return self.parent.open(newreq) def get_cnonce(self, nonce): # The cnonce-value is an opaque # quoted string value provided by the client and used by both client # and server to avoid chosen plaintext attacks, to provide mutual # authentication, and to provide some message integrity protection. # This isn't a fabulous effort, but it's probably Good Enough. dig = sha1_digest("%s:%s:%s:%s" % (self.nonce_count, nonce, time.ctime(), randombytes(8))) return dig[:16] def get_authorization(self, req, chal): try: realm = chal['realm'] nonce = chal['nonce'] qop = chal.get('qop') algorithm = chal.get('algorithm', 'MD5') # mod_digest doesn't send an opaque, even though it isn't # supposed to be optional opaque = chal.get('opaque', None) except KeyError: return None H, KD = self.get_algorithm_impls(algorithm) if H is None: return None user, pw = self.passwd.find_user_password(realm, req.get_full_url()) if user is None: return None # XXX not implemented yet if req.has_data(): entdig = self.get_entity_digest(req.get_data(), chal) else: entdig = None A1 = "%s:%s:%s" % (user, realm, pw) A2 = "%s:%s" % (req.get_method(), # XXX selector: what about proxies and full urls req.get_selector()) if qop == 'auth': if nonce == self.last_nonce: self.nonce_count += 1 else: self.nonce_count = 1 self.last_nonce = nonce ncvalue = '%08x' % self.nonce_count cnonce = self.get_cnonce(nonce) noncebit = "%s:%s:%s:%s:%s" % (nonce, ncvalue, cnonce, qop, H(A2)) respdig = KD(H(A1), noncebit) elif qop is None: respdig = KD(H(A1), "%s:%s" % (nonce, H(A2))) else: # XXX handle auth-int. logger = logging.getLogger("mechanize.auth") logger.info("digest auth auth-int qop is not supported, not " "handling digest authentication") return None # XXX should the partial digests be encoded too? base = 'username="%s", realm="%s", nonce="%s", uri="%s", ' \ 'response="%s"' % (user, realm, nonce, req.get_selector(), respdig) if opaque: base += ', opaque="%s"' % opaque if entdig: base += ', digest="%s"' % entdig base += ', algorithm="%s"' % algorithm if qop: base += ', qop=auth, nc=%s, cnonce="%s"' % (ncvalue, cnonce) return base def get_algorithm_impls(self, algorithm): # algorithm should be case-insensitive according to RFC2617 algorithm = algorithm.upper() if algorithm == 'MD5': H = md5_digest elif algorithm == 'SHA': H = sha1_digest # XXX MD5-sess KD = lambda s, d: H("%s:%s" % (s, d)) # noqa return H, KD def get_entity_digest(self, data, chal): # XXX not implemented yet return None def __copy__(self): return self.__class__(self.passwd.__copy__()) class HTTPDigestAuthHandler(BaseHandler, AbstractDigestAuthHandler): """An authentication protocol defined by RFC 2069 Digest authentication improves on basic authentication because it does not transmit passwords in the clear. """ auth_header = 'Authorization' handler_order = 490 # before Basic auth def http_error_401(self, req, fp, code, msg, headers): host = urlparse(req.get_full_url())[1] retry = self.http_error_auth_reqed('www-authenticate', host, req, headers) self.reset_retry_count() return retry def __copy__(self): return AbstractDigestAuthHandler.__copy__(self) class ProxyDigestAuthHandler(BaseHandler, AbstractDigestAuthHandler): auth_header = 'Proxy-Authorization' handler_order = 490 # before Basic auth def http_error_407(self, req, fp, code, msg, headers): host = req.get_host() retry = self.http_error_auth_reqed('proxy-authenticate', host, req, headers) self.reset_retry_count() return retry def __copy__(self): return AbstractDigestAuthHandler.__copy__(self) class AbstractHTTPHandler(BaseHandler): def __init__(self, debuglevel=0): self._debuglevel = debuglevel def set_http_debuglevel(self, level): self._debuglevel = level def do_request_(self, request): host = request.get_host() if not host: raise URLError('no host given') if request.has_data(): # POST data = request.get_data() if not request.has_header('Content-type'): request.add_unredirected_header( 'Content-type', 'application/x-www-form-urlencoded') if not request.has_header('Content-length'): request.add_unredirected_header( 'Content-length', '%d' % len(data)) sel_host = host if request.has_proxy(): scheme, sel = splittype(request.get_selector()) sel_host, sel_path = splithost(sel) for name, value in self.parent.addheaders: name = name.capitalize() if not request.has_header(name): request.add_unredirected_header(name, value) if not request.has_header('Host'): request.add_unredirected_header('Host', sel_host) return request def do_open(self, http_class, req): """Return an addinfourl object for the request, using http_class. http_class must implement the HTTPConnection API from httplib. The addinfourl return value is a file-like object. It also has methods and attributes including: - info(): return a HTTPMessage object for the headers - geturl(): return the original request URL - code: HTTP status code """ host_port = req.get_host() if not host_port: raise URLError('no host given') h = http_class(host_port, timeout=req.timeout) h.set_debuglevel(self._debuglevel) headers = OrderedDict(req.headers) for key, val in iteritems(req.unredirected_hdrs): headers[key] = val # We want to make an HTTP/1.1 request, but the addinfourl # class isn't prepared to deal with a persistent connection. # It will try to read all remaining data from the socket, # which will block while the server waits for the next request. # So make sure the connection gets closed after the (only) # request. headers["Connection"] = "close" # httplib in python 2 needs str() not unicode() for all request # parameters if is_py2: headers = OrderedDict( (str(name.title()), str(val)) for name, val in iteritems(headers)) else: headers = OrderedDict( (as_unicode(name, 'iso-8859-1').title(), as_unicode(val, 'iso-8859-1')) for name, val in iteritems(headers)) if req._tunnel_host: set_tunnel = h.set_tunnel if hasattr( h, "set_tunnel") else h._set_tunnel tunnel_headers = {} proxy_auth_hdr = "Proxy-Authorization" if proxy_auth_hdr in headers: tunnel_headers[proxy_auth_hdr] = headers[proxy_auth_hdr] # Proxy-Authorization should not be sent to origin server. del headers[proxy_auth_hdr] set_tunnel(req._tunnel_host, headers=tunnel_headers) if self.parent.finalize_request_headers is not None: self.parent.finalize_request_headers(req, headers) try: h.request(str(req.get_method()), str(req.get_selector()), req.data, headers) r = h.getresponse() except socket.error as err: # XXX what error? raise URLError(err) # Pick apart the HTTPResponse object to get the addinfourl # object initialized properly. fp = create_readline_wrapper(r) resp = closeable_response( fp, r.msg, req.get_full_url(), r.status, r.reason, getattr(r, 'version', None)) return resp def __copy__(self): return self.__class__(self._debuglevel) class HTTPHandler(AbstractHTTPHandler): def http_open(self, req): return self.do_open(HTTPConnection, req) http_request = AbstractHTTPHandler.do_request_ class HTTPSHandler(AbstractHTTPHandler): def __init__(self, client_cert_manager=None): AbstractHTTPHandler.__init__(self) self.client_cert_manager = client_cert_manager self.ssl_context = None def https_open(self, req): key_file = cert_file = None if self.client_cert_manager is not None: key_file, cert_file = self.client_cert_manager.find_key_cert( req.get_full_url()) if self.ssl_context is None: conn_factory = partial( HTTPSConnection, key_file=key_file, cert_file=cert_file) else: conn_factory = partial( HTTPSConnection, key_file=key_file, cert_file=cert_file, context=self.ssl_context) return self.do_open(conn_factory, req) https_request = AbstractHTTPHandler.do_request_ def __copy__(self): ans = self.__class__(self.client_cert_manager) ans._debuglevel = self._debuglevel ans.ssl_context = self.ssl_context return ans class HTTPCookieProcessor(BaseHandler): """Handle HTTP cookies. Public attributes: cookiejar: CookieJar instance """ def __init__(self, cookiejar=None): if cookiejar is None: cookiejar = CookieJar() self.cookiejar = cookiejar def http_request(self, request): self.cookiejar.add_cookie_header(request) return request def http_response(self, request, response): self.cookiejar.extract_cookies(response, request) return response def __copy__(self): return self.__class__(self.cookiejar) https_request = http_request https_response = http_response class UnknownHandler(BaseHandler): def unknown_open(self, req): type = req.get_type() raise URLError('unknown url type: %s' % type) def parse_keqv_list(ln): """Parse list of key=value strings where keys are not duplicated.""" parsed = {} for elt in ln: k, v = elt.split('=', 1) if v[0:1] == '"' and v[-1:] == '"': v = v[1:-1] parsed[k] = v return parsed def parse_http_list(s): """Parse lists as described by RFC 2068 Section 2. In particular, parse comma-separated lists where the elements of the list may include quoted-strings. A quoted-string could contain a comma. A non-quoted string could have quotes in the middle. Neither commas nor quotes count if they are escaped. Only double-quotes count, not single-quotes. """ res = [] part = '' escape = quote = False for cur in s: if escape: part += cur escape = False continue if quote: if cur == '\\': escape = True continue elif cur == '"': quote = False part += cur continue if cur == ',': res.append(part) part = '' continue if cur == '"': quote = True part += cur # append last part if part: res.append(part) return list(filter(None, (part_.strip() for part_ in res))) class FileHandler(BaseHandler): # Use local file or FTP depending on form of URL def file_open(self, req): url = req.get_selector() if url[:2] == '//' and url[2:3] != '/': req.type = 'ftp' return self.parent.open(req) else: return self.open_local_file(req) # names for the localhost names = None def get_names(self): if FileHandler.names is None: try: FileHandler.names = (socket.gethostbyname('localhost'), socket.gethostbyname(socket.gethostname()) ) except socket.gaierror: FileHandler.names = (socket.gethostbyname('localhost'),) return FileHandler.names # not entirely sure what the rules are here def open_local_file(self, req): import email.utils as emailutils import mimetypes host = req.get_host() file = req.get_selector() try: localfile = url2pathname(file) except IOError as err: # url2pathname raises this on windows for bad urls raise URLError(err) try: stats = os.stat(localfile) size = stats.st_size modified = emailutils.formatdate(stats.st_mtime, usegmt=True) mtype = mimetypes.guess_type(file)[0] headers = create_response_info(BytesIO( ('Content-type: %s\nContent-length: %d\nLast-modified: %s\n' % (mtype or 'text/plain', size, modified)).encode( 'iso-8859-1'))) if host: host, port = splitport(host) if not host or ( not port and socket.gethostbyname(host) in self.get_names() ): fp = open(localfile, 'rb') return closeable_response(fp, headers, 'file:' + file) except OSError as msg: # urllib2 users shouldn't expect OSErrors coming from urlopen() raise URLError(msg) raise URLError('file not on local host') class FTPHandler(BaseHandler): def ftp_open(self, req): import ftplib import mimetypes host = req.get_host() if not host: raise URLError('ftp error: no host given') host, port = splitport(host) if port is None: port = ftplib.FTP_PORT else: port = int(port) # username/password handling user, host = splituser(host) if user: user, passwd = splitpasswd(user) else: passwd = None host = unquote(host) user = unquote(user or '') passwd = unquote(passwd or '') try: host = socket.gethostbyname(host) except socket.error as msg: raise URLError(msg) path, attrs = splitattr(req.get_selector()) dirs = path.split('/') dirs = list(map(unquote, dirs)) dirs, file = dirs[:-1], dirs[-1] if dirs and not dirs[0]: dirs = dirs[1:] try: fw = self.connect_ftp(user, passwd, host, port, dirs, req.timeout) type = file and 'I' or 'D' for attr in attrs: attr, value = splitvalue(attr) if attr.lower() == 'type' and \ value in ('a', 'A', 'i', 'I', 'd', 'D'): type = value.upper() fp, retrlen = fw.retrfile(file, type) headers = "" mtype = mimetypes.guess_type(req.get_full_url())[0] if mtype: headers += "Content-type: %s\n" % mtype if retrlen is not None and retrlen >= 0: headers += "Content-length: %d\n" % retrlen sf = BytesIO(headers.encode('iso-8859-1')) headers = create_response_info(sf) return closeable_response(fp, headers, req.get_full_url()) except ftplib.all_errors as msg: raise_with_traceback(URLError('ftp error: %s' % msg)) def connect_ftp(self, user, passwd, host, port, dirs, timeout): try: fw = ftpwrapper(user, passwd, host, port, dirs, timeout) except TypeError: # Python < 2.6, no per-connection timeout support fw = ftpwrapper(user, passwd, host, port, dirs) # fw.ftp.set_debuglevel(1) return fw class CacheFTPHandler(FTPHandler): # XXX would be nice to have pluggable cache strategies # XXX this stuff is definitely not thread safe def __init__(self): self.cache = {} self.timeout = {} self.soonest = 0 self.delay = 60 self.max_conns = 16 def setTimeout(self, t): self.delay = t def setMaxConns(self, m): self.max_conns = m def connect_ftp(self, user, passwd, host, port, dirs, timeout): key = user, host, port, '/'.join(dirs), timeout if key in self.cache: self.timeout[key] = time.time() + self.delay else: self.cache[key] = ftpwrapper( user, passwd, host, port, dirs, timeout) self.timeout[key] = time.time() + self.delay self.check_cache() return self.cache[key] def check_cache(self): # first check for old ones t = time.time() if self.soonest <= t: for k, v in iteritems(self.timeout): if v < t: self.cache[k].close() del self.cache[k] del self.timeout[k] self.soonest = min(self.timeout.values()) # then check the size if len(self.cache) == self.max_conns: for k, v in iteritems(self.timeout): if v == self.soonest: del self.cache[k] del self.timeout[k] break self.soonest = min(self.timeout.values())