def dec(cls, s, context=None, safe=False):
if not safe:
return cls.do_dec(s, context, safe)
try:
return cls.do_dec(s, context, safe)
except BER_BadTag_Decoding_Error as e:
o, remain = BERcodec_Object.dec(e.remaining, context, safe)
return ASN1_BADTAG(o), remain
except BER_Decoding_Error as e:
return ASN1_DECODING_ERROR(s, exc=e), ""
except ASN1_Error as e:
return ASN1_DECODING_ERROR(s, exc=e), ""
def dec(cls,
s, # type: bytes
context=None, # type: Optional[Type[ASN1_Class]]
safe=False, # type: bool
):
# type: (...) -> Tuple[Union[_ASN1_ERROR, ASN1_Object[_K]], bytes]
if not safe:
return cls.do_dec(s, context, safe)
try:
return cls.do_dec(s, context, safe)
except BER_BadTag_Decoding_Error as e:
o, remain = BERcodec_Object.dec(
e.remaining, context, safe
) # type: Tuple[ASN1_Object[Any], bytes]
return ASN1_BADTAG(o), remain
except BER_Decoding_Error as e:
return ASN1_DECODING_ERROR(s, exc=e), b""
except ASN1_Error as e:
return ASN1_DECODING_ERROR(s, exc=e), b""
class BERcodec_Object:
__metaclass__ = BERcodec_metaclass
codec = ASN1_Codecs.BER
tag = ASN1_Class_UNIVERSAL.ANY
@classmethod
def asn1_object(cls, val):
return cls.tag.asn1_object(val)
@classmethod
def check_string(cls, s):
if not s:
raise BER_Decoding_Error(
"%s: Got empty object while expecting tag %r" %
(cls.__name__, cls.tag),
remaining=s)
@classmethod
def check_type(cls, s):
cls.check_string(s)
tag, remainder = BER_id_dec(s)
if cls.tag != tag:
raise BER_BadTag_Decoding_Error(
"%s: Got tag [%i/%#x] while expecting %r" %
(cls.__name__, tag, tag, cls.tag),
remaining=s)
return remainder
@classmethod
def check_type_get_len(cls, s):
s2 = cls.check_type(s)
if not s2:
raise BER_Decoding_Error("%s: No bytes while expecting a length" %
cls.__name__,
remaining=s)
return BER_len_dec(s2)
@classmethod
def check_type_check_len(cls, s):
l, s3 = cls.check_type_get_len(s)
if len(s3) < l:
raise BER_Decoding_Error("%s: Got %i bytes while expecting %i" %
(cls.__name__, len(s3), l),
remaining=s)
return l, s3[:l], s3[l:]
@classmethod
def do_dec(cls, s, context=None, safe=False):
if context is None:
context = cls.tag.context
cls.check_string(s)
p, _ = BER_id_dec(s)
if p not in context:
t = s
if len(t) > 18:
t = t[:15] + "..."
raise BER_Decoding_Error("Unknown prefix [%02x] for [%r]" % (p, t),
remaining=s)
codec = context[p].get_codec(ASN1_Codecs.BER)
return codec.dec(s, context, safe)
@classmethod
def dec(cls, s, context=None, safe=False):
if not safe:
return cls.do_dec(s, context, safe)
try:
return cls.do_dec(s, context, safe)
except BER_BadTag_Decoding_Error, e:
o, remain = BERcodec_Object.dec(e.remaining, context, safe)
return ASN1_BADTAG(o), remain
except BER_Decoding_Error, e:
return ASN1_DECODING_ERROR(s, exc=e), ""
codec = context[p].get_codec(ASN1_Codecs.BER)
return codec.dec(s, context, safe)
@classmethod
def dec(cls, s, context=None, safe=False):
if not safe:
return cls.do_dec(s, context, safe)
try:
return cls.do_dec(s, context, safe)
except BER_BadTag_Decoding_Error, e:
o, remain = BERcodec_Object.dec(e.remaining, context, safe)
return ASN1_BADTAG(o), remain
except BER_Decoding_Error, e:
return ASN1_DECODING_ERROR(s, exc=e), ""
except ASN1_Error, e:
return ASN1_DECODING_ERROR(s, exc=e), ""
@classmethod
def safedec(cls, s, context=None):
return cls.dec(s, context, safe=True)
@classmethod
def enc(cls, s):
if type(s) is str:
return BERcodec_STRING.enc(s)
else:
return BERcodec_INTEGER.enc(int(s))
ASN1_Codecs.BER.register_stem(BERcodec_Object)
