4:9
  :   ˆl–ßi~”†»ò‚fãLÜjbÑ¿¿„íˆ?a–Ðz¾”êe¶¥8 pÜiµ1hßÂ ?÷     # This file is dual licensed under the terms of the Apache License, Version
# 2.0, and the BSD License. See the LICENSE file in the root of this repository
# for complete details.

from __future__ import absolute_import, division, print_function

import datetime
import ipaddress

from email.utils import parseaddr

import idna

import six

from six.moves import urllib_parse

from cryptography import x509
from cryptography.x509.oid import (
    CRLEntryExtensionOID, CertificatePoliciesOID, ExtensionOID
)


def _obj2txt(backend, obj):
    # Set to 80 on the recommendation of
    # https://www.openssl.org/docs/crypto/OBJ_nid2ln.html#return_values
    #
    # But OIDs longer than this occur in real life (e.g. Active
    # Directory makes some very long OIDs).  So we need to detect
    # and properly handle the case where the default buffer is not
    # big enough.
    #
    buf_len = 80
    buf = backend._ffi.new("char[]", buf_len)

    # 'res' is the number of bytes that *would* be written if the
    # buffer is large enough.  If 'res' > buf_len - 1, we need to
    # alloc a big-enough buffer and go again.
    res = backend._lib.OBJ_obj2txt(buf, buf_len, obj, 1)
    if res > buf_len - 1:  # account for terminating null byte
        buf_len = res + 1
        buf = backend._ffi.new("char[]", buf_len)
        res = backend._lib.OBJ_obj2txt(buf, buf_len, obj, 1)
    backend.openssl_assert(res > 0)
    return backend._ffi.buffer(buf, res)[:].decode()


def _decode_x509_name_entry(backend, x509_name_entry):
    obj = backend._lib.X509_NAME_ENTRY_get_object(x509_name_entry)
    backend.openssl_assert(obj != backend._ffi.NULL)
    data = backend._lib.X509_NAME_ENTRY_get_data(x509_name_entry)
    backend.openssl_assert(data != backend._ffi.NULL)
    value = _asn1_string_to_utf8(backend, data)
    oid = _obj2txt(backend, obj)

    return x509.NameAttribute(x509.ObjectIdentifier(oid), value)


def _decode_x509_name(backend, x509_name):
    count = backend._lib.X509_NAME_entry_count(x509_name)
    attributes = []
    prev_set_id = -1
    for x in range(count):
        entry = backend._lib.X509_NAME_get_entry(x509_name, x)
        attribute = _decode_x509_name_entry(backend, entry)
        set_id = backend._lib.Cryptography_X509_NAME_ENTRY_set(entry)
        if set_id != prev_set_id:
            attributes.append(set([attribute]))
        else:
            # is in the same RDN a previous entry
            attributes[-1].add(attribute)
        prev_set_id = set_id

    return x509.Name(x509.RelativeDistinguishedName(rdn) for rdn in attributes)


def _decode_general_names(backend, gns):
    num = backend._lib.sk_GENERAL_NAME_num(gns)
    names = []
    for i in range(num):
        gn = backend._lib.sk_GENERAL_NAME_value(gns, i)
        backend.openssl_assert(gn != backend._ffi.NULL)
        names.append(_decode_general_name(backend, gn))

    return names


def _decode_general_name(backend, gn):
    if gn.type == backend._lib.GEN_DNS:
        data = _asn1_string_to_bytes(backend, gn.d.dNSName)
        if not data:
            decoded = u""
        elif data.startswith(b"*."):
            # This is a wildcard name. We need to remove the leading wildcard,
            # IDNA decode, then re-add the wildcard. Wildcard characters should
            # always be left-most (RFC 2595 section 2.4).
            decoded = u"*." + idna.decode(data[2:])
        else:
            # Not a wildcard, decode away. If the string has a * in it anywhere
            # invalid this will raise an InvalidCodePoint
            decoded = idna.decode(data)
            if data.startswith(b"."):
                # idna strips leading periods. Name constraints can have that
                # so we need to re-add it. Sigh.
                decoded = u"." + decoded

        return x509.DNSName(decoded)
    elif gn.type == backend._lib.GEN_URI:
        data = _asn1_string_to_ascii(backend, gn.d.uniformResourceIdentifier)
        parsed = urllib_parse.urlparse(data)
        if parsed.hostname: