Source code for requests.auth

# -*- coding: utf-8 -*-


This module contains the authentication handlers for Requests.

import os
import re
import time
import hashlib
import threading

from base64 import b64encode

from .compat import urlparse, str
from .cookies import extract_cookies_to_jar
from .utils import parse_dict_header, to_native_string
from .status_codes import codes

CONTENT_TYPE_FORM_URLENCODED = 'application/x-www-form-urlencoded'
CONTENT_TYPE_MULTI_PART = 'multipart/form-data'

def _basic_auth_str(username, password):
    """Returns a Basic Auth string."""

    authstr = 'Basic ' + to_native_string(
        b64encode(('%s:%s' % (username, password)).encode('latin1')).strip()

    return authstr

[docs]class AuthBase(object): """Base class that all auth implementations derive from""" def __call__(self, r): raise NotImplementedError('Auth hooks must be callable.')
[docs]class HTTPBasicAuth(AuthBase): """Attaches HTTP Basic Authentication to the given Request object.""" def __init__(self, username, password): self.username = username self.password = password def __eq__(self, other): return all([ self.username == getattr(other, 'username', None), self.password == getattr(other, 'password', None) ]) def __ne__(self, other): return not self == other def __call__(self, r): r.headers['Authorization'] = _basic_auth_str(self.username, self.password) return r
[docs]class HTTPProxyAuth(HTTPBasicAuth): """Attaches HTTP Proxy Authentication to a given Request object.""" def __call__(self, r): r.headers['Proxy-Authorization'] = _basic_auth_str(self.username, self.password) return r
[docs]class HTTPDigestAuth(AuthBase): """Attaches HTTP Digest Authentication to the given Request object.""" def __init__(self, username, password): self.username = username self.password = password # Keep state in per-thread local storage self._thread_local = threading.local() def init_per_thread_state(self): # Ensure state is initialized just once per-thread if not hasattr(self._thread_local, 'init'): self._thread_local.init = True self._thread_local.last_nonce = '' self._thread_local.nonce_count = 0 self._thread_local.chal = {} self._thread_local.pos = None self._thread_local.num_401_calls = None def build_digest_header(self, method, url): realm = self._thread_local.chal['realm'] nonce = self._thread_local.chal['nonce'] qop = self._thread_local.chal.get('qop') algorithm = self._thread_local.chal.get('algorithm') opaque = self._thread_local.chal.get('opaque') hash_utf8 = None if algorithm is None: _algorithm = 'MD5' else: _algorithm = algorithm.upper() # lambdas assume digest modules are imported at the top level if _algorithm == 'MD5' or _algorithm == 'MD5-SESS': def md5_utf8(x): if isinstance(x, str): x = x.encode('utf-8') return hashlib.md5(x).hexdigest() hash_utf8 = md5_utf8 elif _algorithm == 'SHA': def sha_utf8(x): if isinstance(x, str): x = x.encode('utf-8') return hashlib.sha1(x).hexdigest() hash_utf8 = sha_utf8 KD = lambda s, d: hash_utf8("%s:%s" % (s, d)) if hash_utf8 is None: return None # XXX not implemented yet entdig = None p_parsed = urlparse(url) #: path is request-uri defined in RFC 2616 which should not be empty path = p_parsed.path or "/" if p_parsed.query: path += '?' + p_parsed.query A1 = '%s:%s:%s' % (self.username, realm, self.password) A2 = '%s:%s' % (method, path) HA1 = hash_utf8(A1) HA2 = hash_utf8(A2) if nonce == self._thread_local.last_nonce: self._thread_local.nonce_count += 1 else: self._thread_local.nonce_count = 1 ncvalue = '%08x' % self._thread_local.nonce_count s = str(self._thread_local.nonce_count).encode('utf-8') s += nonce.encode('utf-8') s += time.ctime().encode('utf-8') s += os.urandom(8) cnonce = (hashlib.sha1(s).hexdigest()[:16]) if _algorithm == 'MD5-SESS': HA1 = hash_utf8('%s:%s:%s' % (HA1, nonce, cnonce)) if not qop: respdig = KD(HA1, "%s:%s" % (nonce, HA2)) elif qop == 'auth' or 'auth' in qop.split(','): noncebit = "%s:%s:%s:%s:%s" % ( nonce, ncvalue, cnonce, 'auth', HA2 ) respdig = KD(HA1, noncebit) else: # XXX handle auth-int. return None self._thread_local.last_nonce = nonce # XXX should the partial digests be encoded too? base = 'username="%s", realm="%s", nonce="%s", uri="%s", ' \ 'response="%s"' % (self.username, realm, nonce, path, respdig) if opaque: base += ', opaque="%s"' % opaque if algorithm: base += ', algorithm="%s"' % algorithm if entdig: base += ', digest="%s"' % entdig if qop: base += ', qop="auth", nc=%s, cnonce="%s"' % (ncvalue, cnonce) return 'Digest %s' % (base) def handle_redirect(self, r, **kwargs): """Reset num_401_calls counter on redirects.""" if r.is_redirect: self._thread_local.num_401_calls = 1 def handle_401(self, r, **kwargs): """Takes the given response and tries digest-auth, if needed.""" if self._thread_local.pos is not None: # Rewind the file position indicator of the body to where # it was to resend the request. s_auth = r.headers.get('www-authenticate', '') if 'digest' in s_auth.lower() and self._thread_local.num_401_calls < 2: self._thread_local.num_401_calls += 1 pat = re.compile(r'digest ', flags=re.IGNORECASE) self._thread_local.chal = parse_dict_header(pat.sub('', s_auth, count=1)) # Consume content and release the original connection # to allow our new request to reuse the same one. r.content r.close() prep = r.request.copy() extract_cookies_to_jar(prep._cookies, r.request, r.raw) prep.prepare_cookies(prep._cookies) prep.headers['Authorization'] = self.build_digest_header( prep.method, prep.url) _r = r.connection.send(prep, **kwargs) _r.history.append(r) _r.request = prep return _r self._thread_local.num_401_calls = 1 return r def __call__(self, r): # Initialize per-thread state, if needed self.init_per_thread_state() # If we have a saved nonce, skip the 401 if self._thread_local.last_nonce: r.headers['Authorization'] = self.build_digest_header(r.method, r.url) try: self._thread_local.pos = r.body.tell() except AttributeError: # In the case of HTTPDigestAuth being reused and the body of # the previous request was a file-like object, pos has the # file position of the previous body. Ensure it's set to # None. self._thread_local.pos = None r.register_hook('response', self.handle_401) r.register_hook('response', self.handle_redirect) self._thread_local.num_401_calls = 1 return r def __eq__(self, other): return all([ self.username == getattr(other, 'username', None), self.password == getattr(other, 'password', None) ]) def __ne__(self, other): return not self == other