diff options
Diffstat (limited to 'requests/packages/urllib3/packages/ssl_match_hostname/__init__.py')
-rw-r--r-- | requests/packages/urllib3/packages/ssl_match_hostname/__init__.py | 111 |
1 files changed, 13 insertions, 98 deletions
diff --git a/requests/packages/urllib3/packages/ssl_match_hostname/__init__.py b/requests/packages/urllib3/packages/ssl_match_hostname/__init__.py index 2d61ac2..3aa5b2e 100644 --- a/requests/packages/urllib3/packages/ssl_match_hostname/__init__.py +++ b/requests/packages/urllib3/packages/ssl_match_hostname/__init__.py @@ -1,98 +1,13 @@ -"""The match_hostname() function from Python 3.2, essential when using SSL.""" - -import re - -__version__ = '3.2.2' - -class CertificateError(ValueError): - pass - -def _dnsname_match(dn, hostname, max_wildcards=1): - """Matching according to RFC 6125, section 6.4.3 - - http://tools.ietf.org/html/rfc6125#section-6.4.3 - """ - pats = [] - if not dn: - return False - - parts = dn.split(r'.') - leftmost = parts[0] - - wildcards = leftmost.count('*') - if wildcards > max_wildcards: - # Issue #17980: avoid denials of service by refusing more - # than one wildcard per fragment. A survery of established - # policy among SSL implementations showed it to be a - # reasonable choice. - raise CertificateError( - "too many wildcards in certificate DNS name: " + repr(dn)) - - # speed up common case w/o wildcards - if not wildcards: - return dn.lower() == hostname.lower() - - # RFC 6125, section 6.4.3, subitem 1. - # The client SHOULD NOT attempt to match a presented identifier in which - # the wildcard character comprises a label other than the left-most label. - if leftmost == '*': - # When '*' is a fragment by itself, it matches a non-empty dotless - # fragment. - pats.append('[^.]+') - elif leftmost.startswith('xn--') or hostname.startswith('xn--'): - # RFC 6125, section 6.4.3, subitem 3. - # The client SHOULD NOT attempt to match a presented identifier - # where the wildcard character is embedded within an A-label or - # U-label of an internationalized domain name. - pats.append(re.escape(leftmost)) - else: - # Otherwise, '*' matches any dotless string, e.g. www* - pats.append(re.escape(leftmost).replace(r'\*', '[^.]*')) - - # add the remaining fragments, ignore any wildcards - for frag in parts[1:]: - pats.append(re.escape(frag)) - - pat = re.compile(r'\A' + r'\.'.join(pats) + r'\Z', re.IGNORECASE) - return pat.match(hostname) - - -def match_hostname(cert, hostname): - """Verify that *cert* (in decoded format as returned by - SSLSocket.getpeercert()) matches the *hostname*. RFC 2818 and RFC 6125 - rules are 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_match(value, 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_match(value, 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") +try: + # Python 3.2+ + from ssl import CertificateError, match_hostname +except ImportError: + try: + # Backport of the function from a pypi module + from backports.ssl_match_hostname import CertificateError, match_hostname + except ImportError: + # Our vendored copy + from _implementation import CertificateError, match_hostname + +# Not needed, but documenting what we provide. +__all__ = ('CertificateError', 'match_hostname') |