http digest auth: reset redirect counter on new requests (issue2255)

This fixes a regression introduced in a1e575b48563 when Mercurial reuses the
auth handler for several requests and the redirect counter never is reset.

mercurial/url.py

@@ -1,634 +1,641 b''
 # url.py - HTTP handling for mercurial
 #
 # Copyright 2005, 2006, 2007, 2008 Matt Mackall <[e-mail]>
 # Copyright 2006, 2007 Alexis S. L. Carvalho <[e-mail]>
 # Copyright 2006 Vadim Gelfer <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 import urllib, urllib2, urlparse, httplib, os, re, socket, cStringIO
 from i18n import _
 import keepalive, util
 
 def _urlunparse(scheme, netloc, path, params, query, fragment, url):
     '''Handle cases where urlunparse(urlparse(x://)) doesn't preserve the "//"'''
     result = urlparse.urlunparse((scheme, netloc, path, params, query, fragment))
     if (scheme and
         result.startswith(scheme + ':') and
         not result.startswith(scheme + '://') and
         url.startswith(scheme + '://')
        ):
         result = scheme + '://' + result[len(scheme + ':'):]
     return result
 
 def hidepassword(url):
     '''hide user credential in a url string'''
     scheme, netloc, path, params, query, fragment = urlparse.urlparse(url)
     netloc = re.sub('([^:]*):([^@]*)@(.*)', r'\1:***@\3', netloc)
     return _urlunparse(scheme, netloc, path, params, query, fragment, url)
 
 def removeauth(url):
     '''remove all authentication information from a url string'''
     scheme, netloc, path, params, query, fragment = urlparse.urlparse(url)
     netloc = netloc[netloc.find('@')+1:]
     return _urlunparse(scheme, netloc, path, params, query, fragment, url)
 
 def netlocsplit(netloc):
     '''split [user[:passwd]@]host[:port] into 4-tuple.'''
 
     a = netloc.find('@')
     if a == -1:
         user, passwd = None, None
     else:
         userpass, netloc = netloc[:a], netloc[a + 1:]
         c = userpass.find(':')
         if c == -1:
             user, passwd = urllib.unquote(userpass), None
         else:
             user = urllib.unquote(userpass[:c])
             passwd = urllib.unquote(userpass[c + 1:])
     c = netloc.find(':')
     if c == -1:
         host, port = netloc, None
     else:
         host, port = netloc[:c], netloc[c + 1:]
     return host, port, user, passwd
 
 def netlocunsplit(host, port, user=None, passwd=None):
     '''turn host, port, user, passwd into [user[:passwd]@]host[:port].'''
     if port:
         hostport = host + ':' + port
     else:
         hostport = host
     if user:
         quote = lambda s: urllib.quote(s, safe='')
         if passwd:
             userpass = quote(user) + ':' + quote(passwd)
         else:
             userpass = quote(user)
         return userpass + '@' + hostport
     return hostport
 
 _safe = ('abcdefghijklmnopqrstuvwxyz'
          'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
          '0123456789' '_.-/')
 _safeset = None
 _hex = None
 def quotepath(path):
     '''quote the path part of a URL
 
     This is similar to urllib.quote, but it also tries to avoid
     quoting things twice (inspired by wget):
 
     >>> quotepath('abc def')
     'abc%20def'
     >>> quotepath('abc%20def')
     'abc%20def'
     >>> quotepath('abc%20 def')
     'abc%20%20def'
     >>> quotepath('abc def%20')
     'abc%20def%20'
     >>> quotepath('abc def%2')
     'abc%20def%252'
     >>> quotepath('abc def%')
     'abc%20def%25'
     '''
     global _safeset, _hex
     if _safeset is None:
         _safeset = set(_safe)
         _hex = set('abcdefABCDEF0123456789')
     l = list(path)
     for i in xrange(len(l)):
         c = l[i]
         if (c == '%' and i + 2 < len(l) and
             l[i + 1] in _hex and l[i + 2] in _hex):
             pass
         elif c not in _safeset:
             l[i] = '%%%02X' % ord(c)
     return ''.join(l)
 
 class passwordmgr(urllib2.HTTPPasswordMgrWithDefaultRealm):
     def __init__(self, ui):
         urllib2.HTTPPasswordMgrWithDefaultRealm.__init__(self)
         self.ui = ui
 
     def find_user_password(self, realm, authuri):
         authinfo = urllib2.HTTPPasswordMgrWithDefaultRealm.find_user_password(
             self, realm, authuri)
         user, passwd = authinfo
         if user and passwd:
             self._writedebug(user, passwd)
             return (user, passwd)
 
         if not user:
             auth = self.readauthtoken(authuri)
             if auth:
                 user, passwd = auth.get('username'), auth.get('password')
         if not user or not passwd:
             if not self.ui.interactive():
                 raise util.Abort(_('http authorization required'))
 
             self.ui.write(_("http authorization required\n"))
             self.ui.status(_("realm: %s\n") % realm)
             if user:
                 self.ui.status(_("user: %s\n") % user)
             else:
                 user = self.ui.prompt(_("user:"), default=None)
 
             if not passwd:
                 passwd = self.ui.getpass()
 
         self.add_password(realm, authuri, user, passwd)
         self._writedebug(user, passwd)
         return (user, passwd)
 
     def _writedebug(self, user, passwd):
         msg = _('http auth: user %s, password %s\n')
         self.ui.debug(msg % (user, passwd and '*' * len(passwd) or 'not set'))
 
     def readauthtoken(self, uri):
         # Read configuration
         config = dict()
         for key, val in self.ui.configitems('auth'):
             if '.' not in key:
                 self.ui.warn(_("ignoring invalid [auth] key '%s'\n") % key)
                 continue
             group, setting = key.split('.', 1)
             gdict = config.setdefault(group, dict())
             if setting in ('cert', 'key'):
                 val = util.expandpath(val)
             gdict[setting] = val
 
         # Find the best match
         scheme, hostpath = uri.split('://', 1)
         bestlen = 0
         bestauth = None
         for auth in config.itervalues():
             prefix = auth.get('prefix')
             if not prefix:
                 continue
             p = prefix.split('://', 1)
             if len(p) > 1:
                 schemes, prefix = [p[0]], p[1]
             else:
                 schemes = (auth.get('schemes') or 'https').split()
             if (prefix == '*' or hostpath.startswith(prefix)) and \
                 len(prefix) > bestlen and scheme in schemes:
                 bestlen = len(prefix)
                 bestauth = auth
         return bestauth
 
 class proxyhandler(urllib2.ProxyHandler):
     def __init__(self, ui):
         proxyurl = ui.config("http_proxy", "host") or os.getenv('http_proxy')
         # XXX proxyauthinfo = None
 
         if proxyurl:
             # proxy can be proper url or host[:port]
             if not (proxyurl.startswith('http:') or
                     proxyurl.startswith('https:')):
                 proxyurl = 'http://' + proxyurl + '/'
             snpqf = urlparse.urlsplit(proxyurl)
             proxyscheme, proxynetloc, proxypath, proxyquery, proxyfrag = snpqf
             hpup = netlocsplit(proxynetloc)
 
             proxyhost, proxyport, proxyuser, proxypasswd = hpup
             if not proxyuser:
                 proxyuser = ui.config("http_proxy", "user")
                 proxypasswd = ui.config("http_proxy", "passwd")
 
             # see if we should use a proxy for this url
             no_list = ["localhost", "127.0.0.1"]
             no_list.extend([p.lower() for
                             p in ui.configlist("http_proxy", "no")])
             no_list.extend([p.strip().lower() for
                             p in os.getenv("no_proxy", '').split(',')
                             if p.strip()])
             # "http_proxy.always" config is for running tests on localhost
             if ui.configbool("http_proxy", "always"):
                 self.no_list = []
             else:
                 self.no_list = no_list
 
             proxyurl = urlparse.urlunsplit((
                 proxyscheme, netlocunsplit(proxyhost, proxyport,
                                                 proxyuser, proxypasswd or ''),
                 proxypath, proxyquery, proxyfrag))
             proxies = {'http': proxyurl, 'https': proxyurl}
             ui.debug('proxying through http://%s:%s\n' %
                       (proxyhost, proxyport))
         else:
             proxies = {}
 
         # urllib2 takes proxy values from the environment and those
         # will take precedence if found, so drop them
         for env in ["HTTP_PROXY", "http_proxy", "no_proxy"]:
             try:
                 if env in os.environ:
                     del os.environ[env]
             except OSError:
                 pass
 
         urllib2.ProxyHandler.__init__(self, proxies)
         self.ui = ui
 
     def proxy_open(self, req, proxy, type_):
         host = req.get_host().split(':')[0]
         if host in self.no_list:
             return None
 
         # work around a bug in Python < 2.4.2
         # (it leaves a "\n" at the end of Proxy-authorization headers)
         baseclass = req.__class__
         class _request(baseclass):
             def add_header(self, key, val):
                 if key.lower() == 'proxy-authorization':
                     val = val.strip()
                 return baseclass.add_header(self, key, val)
         req.__class__ = _request
 
         return urllib2.ProxyHandler.proxy_open(self, req, proxy, type_)
 
 class httpsendfile(file):
     def __len__(self):
         return os.fstat(self.fileno()).st_size
 
 def _gen_sendfile(connection):
     def _sendfile(self, data):
         # send a file
         if isinstance(data, httpsendfile):
             # if auth required, some data sent twice, so rewind here
             data.seek(0)
             for chunk in util.filechunkiter(data):
                 connection.send(self, chunk)
         else:
             connection.send(self, data)
     return _sendfile
 
 has_https = hasattr(urllib2, 'HTTPSHandler')
 if has_https:
     try:
         # avoid using deprecated/broken FakeSocket in python 2.6
         import ssl
         _ssl_wrap_socket = ssl.wrap_socket
         CERT_REQUIRED = ssl.CERT_REQUIRED
     except ImportError:
         CERT_REQUIRED = 2
 
         def _ssl_wrap_socket(sock, key_file, cert_file,
                              cert_reqs=CERT_REQUIRED, ca_certs=None):
             if ca_certs:
                 raise util.Abort(_(
                     'certificate checking requires Python 2.6'))
 
             ssl = socket.ssl(sock, key_file, cert_file)
             return httplib.FakeSocket(sock, ssl)
 
     try:
         _create_connection = socket.create_connection
     except AttributeError:
         _GLOBAL_DEFAULT_TIMEOUT = object()
 
         def _create_connection(address, timeout=_GLOBAL_DEFAULT_TIMEOUT,
                                source_address=None):
             # lifted from Python 2.6
 
             msg = "getaddrinfo returns an empty list"
             host, port = address
             for res in socket.getaddrinfo(host, port, 0, socket.SOCK_STREAM):
                 af, socktype, proto, canonname, sa = res
                 sock = None
                 try:
                     sock = socket.socket(af, socktype, proto)
                     if timeout is not _GLOBAL_DEFAULT_TIMEOUT:
                         sock.settimeout(timeout)
                     if source_address:
                         sock.bind(source_address)
                     sock.connect(sa)
                     return sock
 
                 except socket.error, msg:
                     if sock is not None:
                         sock.close()
 
             raise socket.error, msg
 
 class httpconnection(keepalive.HTTPConnection):
     # must be able to send big bundle as stream.
     send = _gen_sendfile(keepalive.HTTPConnection)
 
     def connect(self):
         if has_https and self.realhostport: # use CONNECT proxy
             self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
             self.sock.connect((self.host, self.port))
             if _generic_proxytunnel(self):
                 # we do not support client x509 certificates
                 self.sock = _ssl_wrap_socket(self.sock, None, None)
         else:
             keepalive.HTTPConnection.connect(self)
 
     def getresponse(self):
         proxyres = getattr(self, 'proxyres', None)
         if proxyres:
             if proxyres.will_close:
                 self.close()
             self.proxyres = None
             return proxyres
         return keepalive.HTTPConnection.getresponse(self)
 
 # general transaction handler to support different ways to handle
 # HTTPS proxying before and after Python 2.6.3.
 def _generic_start_transaction(handler, h, req):
     if hasattr(req, '_tunnel_host') and req._tunnel_host:
         tunnel_host = req._tunnel_host
         if tunnel_host[:7] not in ['http://', 'https:/']:
             tunnel_host = 'https://' + tunnel_host
         new_tunnel = True
     else:
         tunnel_host = req.get_selector()
         new_tunnel = False
 
     if new_tunnel or tunnel_host == req.get_full_url(): # has proxy
         urlparts = urlparse.urlparse(tunnel_host)
         if new_tunnel or urlparts[0] == 'https': # only use CONNECT for HTTPS
             realhostport = urlparts[1]
             if realhostport[-1] == ']' or ':' not in realhostport:
                 realhostport += ':443'
 
             h.realhostport = realhostport
             h.headers = req.headers.copy()
             h.headers.update(handler.parent.addheaders)
             return
 
     h.realhostport = None
     h.headers = None
 
 def _generic_proxytunnel(self):
     proxyheaders = dict(
             [(x, self.headers[x]) for x in self.headers
              if x.lower().startswith('proxy-')])
     self._set_hostport(self.host, self.port)
     self.send('CONNECT %s HTTP/1.0\r\n' % self.realhostport)
     for header in proxyheaders.iteritems():
         self.send('%s: %s\r\n' % header)
     self.send('\r\n')
 
     # majority of the following code is duplicated from
     # httplib.HTTPConnection as there are no adequate places to
     # override functions to provide the needed functionality
     res = self.response_class(self.sock,
                               strict=self.strict,
                               method=self._method)
 
     while True:
         version, status, reason = res._read_status()
         if status != httplib.CONTINUE:
             break
         while True:
             skip = res.fp.readline().strip()
             if not skip:
                 break
     res.status = status
     res.reason = reason.strip()
 
     if res.status == 200:
         while True:
             line = res.fp.readline()
             if line == '\r\n':
                 break
         return True
 
     if version == 'HTTP/1.0':
         res.version = 10
     elif version.startswith('HTTP/1.'):
         res.version = 11
     elif version == 'HTTP/0.9':
         res.version = 9
     else:
         raise httplib.UnknownProtocol(version)
 
     if res.version == 9:
         res.length = None
         res.chunked = 0
         res.will_close = 1
         res.msg = httplib.HTTPMessage(cStringIO.StringIO())
         return False
 
     res.msg = httplib.HTTPMessage(res.fp)
     res.msg.fp = None
 
     # are we using the chunked-style of transfer encoding?
     trenc = res.msg.getheader('transfer-encoding')
     if trenc and trenc.lower() == "chunked":
         res.chunked = 1
         res.chunk_left = None
     else:
         res.chunked = 0
 
     # will the connection close at the end of the response?
     res.will_close = res._check_close()
 
     # do we have a Content-Length?
     # NOTE: RFC 2616, S4.4, #3 says we ignore this if tr_enc is "chunked"
     length = res.msg.getheader('content-length')
     if length and not res.chunked:
         try:
             res.length = int(length)
         except ValueError:
             res.length = None
         else:
             if res.length < 0:  # ignore nonsensical negative lengths
                 res.length = None
     else:
         res.length = None
 
     # does the body have a fixed length? (of zero)
     if (status == httplib.NO_CONTENT or status == httplib.NOT_MODIFIED or
         100 <= status < 200 or # 1xx codes
         res._method == 'HEAD'):
         res.length = 0
 
     # if the connection remains open, and we aren't using chunked, and
     # a content-length was not provided, then assume that the connection
     # WILL close.
     if (not res.will_close and
        not res.chunked and
        res.length is None):
         res.will_close = 1
 
     self.proxyres = res
 
     return False
 
 class httphandler(keepalive.HTTPHandler):
     def http_open(self, req):
         return self.do_open(httpconnection, req)
 
     def _start_transaction(self, h, req):
         _generic_start_transaction(self, h, req)
         return keepalive.HTTPHandler._start_transaction(self, h, req)
 
     def __del__(self):
         self.close_all()
 
 if has_https:
     class BetterHTTPS(httplib.HTTPSConnection):
         send = keepalive.safesend
 
         def connect(self):
             if hasattr(self, 'ui'):
                 cacerts = self.ui.config('web', 'cacerts')
             else:
                 cacerts = None
 
             if cacerts:
                 sock = _create_connection((self.host, self.port))
                 self.sock = _ssl_wrap_socket(sock, self.key_file,
                         self.cert_file, cert_reqs=CERT_REQUIRED,
                         ca_certs=cacerts)
                 self.ui.debug(_('server identity verification succeeded\n'))
             else:
                 httplib.HTTPSConnection.connect(self)
 
     class httpsconnection(BetterHTTPS):
         response_class = keepalive.HTTPResponse
         # must be able to send big bundle as stream.
         send = _gen_sendfile(BetterHTTPS)
         getresponse = keepalive.wrapgetresponse(httplib.HTTPSConnection)
 
         def connect(self):
             if self.realhostport: # use CONNECT proxy
                 self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
                 self.sock.connect((self.host, self.port))
                 if _generic_proxytunnel(self):
                     self.sock = _ssl_wrap_socket(self.sock, self.cert_file,
                                                  self.key_file)
             else:
                 BetterHTTPS.connect(self)
 
     class httpshandler(keepalive.KeepAliveHandler, urllib2.HTTPSHandler):
         def __init__(self, ui):
             keepalive.KeepAliveHandler.__init__(self)
             urllib2.HTTPSHandler.__init__(self)
             self.ui = ui
             self.pwmgr = passwordmgr(self.ui)
 
         def _start_transaction(self, h, req):
             _generic_start_transaction(self, h, req)
             return keepalive.KeepAliveHandler._start_transaction(self, h, req)
 
         def https_open(self, req):
             self.auth = self.pwmgr.readauthtoken(req.get_full_url())
             return self.do_open(self._makeconnection, req)
 
         def _makeconnection(self, host, port=None, *args, **kwargs):
             keyfile = None
             certfile = None
 
             if len(args) >= 1: # key_file
                 keyfile = args[0]
             if len(args) >= 2: # cert_file
                 certfile = args[1]
             args = args[2:]
 
             # if the user has specified different key/cert files in
             # hgrc, we prefer these
             if self.auth and 'key' in self.auth and 'cert' in self.auth:
                 keyfile = self.auth['key']
                 certfile = self.auth['cert']
 
             conn = httpsconnection(host, port, keyfile, certfile, *args, **kwargs)
             conn.ui = self.ui
             return conn
 
-# In python < 2.5 AbstractDigestAuthHandler raises a ValueError if
-# it doesn't know about the auth type requested.  This can happen if
-# somebody is using BasicAuth and types a bad password.
 class httpdigestauthhandler(urllib2.HTTPDigestAuthHandler):
+    def __init__(self, *args, **kwargs):
+        urllib2.HTTPDigestAuthHandler.__init__(self, *args, **kwargs)
+        self.retried_req = None
+
+    def reset_retry_count(self):
+        # Python 2.6.5 will call this on 401 or 407 errors and thus loop
+        # forever. We disable reset_retry_count completely and reset in
+        # http_error_auth_reqed instead.
+        pass
+
     def http_error_auth_reqed(self, auth_header, host, req, headers):
+        # Reset the retry counter once for each request.
+        if req is not self.retried_req:
+            self.retried_req = req
+            self.retried = 0
+        # In python < 2.5 AbstractDigestAuthHandler raises a ValueError if
+        # it doesn't know about the auth type requested. This can happen if
+        # somebody is using BasicAuth and types a bad password.
         try:
             return urllib2.HTTPDigestAuthHandler.http_error_auth_reqed(
                         self, auth_header, host, req, headers)
         except ValueError, inst:
             arg = inst.args[0]
             if arg.startswith("AbstractDigestAuthHandler doesn't know "):
                 return
             raise
 
-    # Python 2.6.5 will keep resetting the retry count on redirects, for
-    # example when the server returns 401 on failing auth (like google code
-    # currently does). We stop the endless recursion by not resetting the
-    # count.
-    def reset_retry_count(self):
-        pass
-
 def getauthinfo(path):
     scheme, netloc, urlpath, query, frag = urlparse.urlsplit(path)
     if not urlpath:
         urlpath = '/'
     if scheme != 'file':
         # XXX: why are we quoting the path again with some smart
         # heuristic here? Anyway, it cannot be done with file://
         # urls since path encoding is os/fs dependent (see
         # urllib.pathname2url() for details).
         urlpath = quotepath(urlpath)
     host, port, user, passwd = netlocsplit(netloc)
 
     # urllib cannot handle URLs with embedded user or passwd
     url = urlparse.urlunsplit((scheme, netlocunsplit(host, port),
                               urlpath, query, frag))
     if user:
         netloc = host
         if port:
             netloc += ':' + port
         # Python < 2.4.3 uses only the netloc to search for a password
         authinfo = (None, (url, netloc), user, passwd or '')
     else:
         authinfo = None
     return url, authinfo
 
 handlerfuncs = []
 
 def opener(ui, authinfo=None):
     '''
     construct an opener suitable for urllib2
     authinfo will be added to the password manager
     '''
     handlers = [httphandler()]
     if has_https:
         handlers.append(httpshandler(ui))
 
     handlers.append(proxyhandler(ui))
 
     passmgr = passwordmgr(ui)
     if authinfo is not None:
         passmgr.add_password(*authinfo)
         user, passwd = authinfo[2:4]
         ui.debug('http auth: user %s, password %s\n' %
                  (user, passwd and '*' * len(passwd) or 'not set'))
 
     handlers.extend((urllib2.HTTPBasicAuthHandler(passmgr),
                      httpdigestauthhandler(passmgr)))
     handlers.extend([h(ui, passmgr) for h in handlerfuncs])
     opener = urllib2.build_opener(*handlers)
 
     # 1.0 here is the _protocol_ version
     opener.addheaders = [('User-agent', 'mercurial/proto-1.0')]
     opener.addheaders.append(('Accept', 'application/mercurial-0.1'))
     return opener
 
 scheme_re = re.compile(r'^([a-zA-Z0-9+-.]+)://')
 
 def open(ui, url, data=None):
     scheme = None
     m = scheme_re.search(url)
     if m:
         scheme = m.group(1).lower()
     if not scheme:
         path = util.normpath(os.path.abspath(url))
         url = 'file://' + urllib.pathname2url(path)
         authinfo = None
     else:
         url, authinfo = getauthinfo(url)
     return opener(ui, authinfo).open(url, data)