diff options
Diffstat (limited to 'setuptools/ssl_support.py')
| -rw-r--r-- | setuptools/ssl_support.py | 246 |
1 files changed, 246 insertions, 0 deletions
diff --git a/setuptools/ssl_support.py b/setuptools/ssl_support.py new file mode 100644 index 0000000..f1d8c92 --- /dev/null +++ b/setuptools/ssl_support.py @@ -0,0 +1,246 @@ +import sys, os, socket, urllib2, atexit, re +from pkg_resources import ResolutionError, ExtractionError + +try: + import ssl +except ImportError: + ssl = None + +__all__ = [ + 'VerifyingHTTPSHandler', 'find_ca_bundle', 'is_available', 'cert_paths', + 'opener_for' +] + +cert_paths = """ +/etc/pki/tls/certs/ca-bundle.crt +/etc/ssl/certs/ca-certificates.crt +/usr/share/ssl/certs/ca-bundle.crt +/usr/local/share/certs/ca-root.crt +/etc/ssl/cert.pem +/System/Library/OpenSSL/certs/cert.pem +""".strip().split() + + +HTTPSHandler = HTTPSConnection = object + +for what, where in ( + ('HTTPSHandler', ['urllib2','urllib.request']), + ('HTTPSConnection', ['httplib', 'http.client']), +): + for module in where: + try: + exec("from %s import %s" % (module, what)) + except ImportError: + pass + +is_available = ssl is not None and object not in (HTTPSHandler, HTTPSConnection) + + + + + +try: + from socket import create_connection +except ImportError: + _GLOBAL_DEFAULT_TIMEOUT = getattr(socket, '_GLOBAL_DEFAULT_TIMEOUT', object()) + def create_connection(address, timeout=_GLOBAL_DEFAULT_TIMEOUT, + source_address=None): + """Connect to *address* and return the socket object. + + Convenience function. Connect to *address* (a 2-tuple ``(host, + port)``) and return the socket object. Passing the optional + *timeout* parameter will set the timeout on the socket instance + before attempting to connect. If no *timeout* is supplied, the + global default timeout setting returned by :func:`getdefaulttimeout` + is used. If *source_address* is set it must be a tuple of (host, port) + for the socket to bind as a source address before making the connection. + An host of '' or port 0 tells the OS to use the default. + """ + host, port = address + err = None + 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 error: + err = True + if sock is not None: + sock.close() + if err: + raise + else: + raise error("getaddrinfo returns an empty list") + + +try: + from ssl import CertificateError, match_hostname +except ImportError: + class CertificateError(ValueError): + pass + + def _dnsname_to_pat(dn): + pats = [] + for frag in dn.split(r'.'): + if frag == '*': + # When '*' is a fragment by itself, it matches a non-empty dotless + # fragment. + pats.append('[^.]+') + else: + # Otherwise, '*' matches any dotless fragment. + frag = re.escape(frag) + pats.append(frag.replace(r'\*', '[^.]*')) + return re.compile(r'\A' + r'\.'.join(pats) + r'\Z', re.IGNORECASE) + + def match_hostname(cert, hostname): + """Verify that *cert* (in decoded format as returned by + SSLSocket.getpeercert()) matches the *hostname*. RFC 2818 rules + are mostly followed, but IP addresses are not accepted for *hostname*. + + CertificateError is raised on failure. On success, the function + returns nothing. + """ + if not cert: + raise ValueError("empty or no certificate") + dnsnames = [] + san = cert.get('subjectAltName', ()) + for key, value in san: + if key == 'DNS': + if _dnsname_to_pat(value).match(hostname): + return + dnsnames.append(value) + if not dnsnames: + # The subject is only checked when there is no dNSName entry + # in subjectAltName + for sub in cert.get('subject', ()): + for key, value in sub: + # XXX according to RFC 2818, the most specific Common Name + # must be used. + if key == 'commonName': + if _dnsname_to_pat(value).match(hostname): + return + dnsnames.append(value) + if len(dnsnames) > 1: + raise CertificateError("hostname %r " + "doesn't match either of %s" + % (hostname, ', '.join(map(repr, dnsnames)))) + elif len(dnsnames) == 1: + raise CertificateError("hostname %r " + "doesn't match %r" + % (hostname, dnsnames[0])) + else: + raise CertificateError("no appropriate commonName or " + "subjectAltName fields were found") + + + + + + + + + + + + + + + + + + + + + + + + +class VerifyingHTTPSHandler(HTTPSHandler): + """Simple verifying handler: no auth, subclasses, timeouts, etc.""" + + def __init__(self, ca_bundle): + self.ca_bundle = ca_bundle + HTTPSHandler.__init__(self) + + def https_open(self, req): + return self.do_open( + lambda host, **kw: VerifyingHTTPSConn(host, self.ca_bundle, **kw), req + ) + + +class VerifyingHTTPSConn(HTTPSConnection): + """Simple verifying connection: no auth, subclasses, timeouts, etc.""" + def __init__(self, host, ca_bundle, **kw): + HTTPSConnection.__init__(self, host, **kw) + self.ca_bundle = ca_bundle + + def connect(self): + sock = create_connection( + (self.host, self.port), getattr(self,'source_address',None) + ) + self.sock = ssl.wrap_socket( + sock, cert_reqs=ssl.CERT_REQUIRED, ca_certs=self.ca_bundle + ) + try: + match_hostname(self.sock.getpeercert(), self.host) + except CertificateError: + self.sock.shutdown(socket.SHUT_RDWR) + self.sock.close() + raise + +def opener_for(ca_bundle=None): + """Get a urlopen() replacement that uses ca_bundle for verification""" + return urllib2.build_opener( + VerifyingHTTPSHandler(ca_bundle or find_ca_bundle()) + ).open + + + +_wincerts = None + +def get_win_certfile(): + global _wincerts + if _wincerts is not None: + return _wincerts.name + + try: + from wincertstore import CertFile + except ImportError: + return None + + class MyCertFile(CertFile): + def __init__(self, stores=(), certs=()): + CertFile.__init__(self) + for store in stores: + self.addstore(store) + self.addcerts(certs) + atexit.register(self.close) + + _wincerts = MyCertFile(stores=['CA', 'ROOT']) + return _wincerts.name + + +def find_ca_bundle(): + """Return an existing CA bundle path, or None""" + if os.name=='nt': + return get_win_certfile() + else: + for cert_path in cert_paths: + if os.path.isfile(cert_path): + return cert_path + try: + return pkg_resources.resource_filename('certifi', 'cacert.pem') + except (ImportError, ResolutionError, ExtractionError): + return None + + + + + |