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Diffstat (limited to 'scripts/external_libs/scapy-python3-0.18/scapy/asn1/ber.py')
| -rw-r--r-- | scripts/external_libs/scapy-python3-0.18/scapy/asn1/ber.py | 370 |
1 files changed, 0 insertions, 370 deletions
diff --git a/scripts/external_libs/scapy-python3-0.18/scapy/asn1/ber.py b/scripts/external_libs/scapy-python3-0.18/scapy/asn1/ber.py deleted file mode 100644 index 48cb1c2d..00000000 --- a/scripts/external_libs/scapy-python3-0.18/scapy/asn1/ber.py +++ /dev/null @@ -1,370 +0,0 @@ -## This file is part of Scapy -## See http://www.secdev.org/projects/scapy for more informations -## Copyright (C) Philippe Biondi <phil@secdev.org> -## This program is published under a GPLv2 license - -""" -Basic Encoding Rules (BER) for ASN.1 -""" - -from scapy.error import warning -from scapy.utils import inet_aton,inet_ntoa -from scapy.asn1.asn1 import ASN1_Decoding_Error,ASN1_Encoding_Error,ASN1_BadTag_Decoding_Error,ASN1_Codecs,ASN1_Class_UNIVERSAL,ASN1_Error,ASN1_DECODING_ERROR,ASN1_BADTAG - -################## -## BER encoding ## -################## - - - -#####[ BER tools ]##### - - -class BER_Exception(Exception): - pass - -class BER_Encoding_Error(ASN1_Encoding_Error): - def __init__(self, msg, encoded=None, remaining=None): - Exception.__init__(self, msg) - self.remaining = remaining - self.encoded = encoded - def __str__(self): - s = Exception.__str__(self) - if isinstance(self.encoded, BERcodec_Object): - s+="\n### Already encoded ###\n%s" % self.encoded.strshow() - else: - s+="\n### Already encoded ###\n%r" % self.encoded - s+="\n### Remaining ###\n%r" % self.remaining - return s - -class BER_Decoding_Error(ASN1_Decoding_Error): - def __init__(self, msg, decoded=None, remaining=None): - Exception.__init__(self, msg) - self.remaining = remaining - self.decoded = decoded - def __str__(self): - s = Exception.__str__(self) - if isinstance(self.decoded, BERcodec_Object): - s+="\n### Already decoded ###\n%s" % self.decoded.strshow() - else: - s+="\n### Already decoded ###\n%r" % self.decoded - s+="\n### Remaining ###\n%r" % self.remaining - return s - -class BER_BadTag_Decoding_Error(BER_Decoding_Error, ASN1_BadTag_Decoding_Error): - pass - -def BER_len_enc(l, size=0): - if l <= 127 and size==0: - return bytes([l]) - s = b"" - while l or size>0: - s = bytes([l&0xff])+s - l >>= 8 - size -= 1 - if len(s) > 127: - raise BER_Exception("BER_len_enc: Length too long (%i) to be encoded [%r]" % (len(s),s)) - return bytes([len(s)|0x80])+s -def BER_len_dec(s): - l = (s[0]) - if not l & 0x80: - return l,s[1:] - l &= 0x7f - if len(s) <= l: - raise BER_Decoding_Error("BER_len_dec: Got %i bytes while expecting %i" % (len(s)-1, l),remaining=s) - ll = 0 - for c in s[1:l+1]: - ll <<= 8 - ll |= (c) - return ll,s[l+1:] - -def BER_num_enc(l, size=1): - x=[] - while l or size>0: - x.insert(0, l & 0x7f) - if len(x) > 1: - x[0] |= 0x80 - l >>= 7 - size -= 1 - return bytes([(k) for k in x]) -def BER_num_dec(s): - x = 0 - for i in range(len(s)): - c = (s[i]) - x <<= 7 - x |= c&0x7f - if not c&0x80: - break - if c&0x80: - raise BER_Decoding_Error("BER_num_dec: unfinished number description", remaining=s) - return x, s[i+1:] - -#####[ BER classes ]##### - -class BERcodec_metaclass(type): - def __new__(cls, name, bases, dct): - c = super(BERcodec_metaclass, cls).__new__(cls, name, bases, dct) - try: - c.tag.register(c.codec, c) - except: - warning("Error registering %r for %r" % (c.tag, c.codec)) - return c - - -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) - if hash(cls.tag) != (s[0]): - raise BER_BadTag_Decoding_Error("%s: Got tag [%i/%#x] while expecting %r" % - (cls.__name__, (s[0]), (s[0]),cls.tag), remaining=s) - return s[1:] - @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 = (s[0]) - 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 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),"" - - @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) - #TODO3 wild guess - elif type(s) is bytes: - return BERcodec_STRING.enc(s) - else: - return BERcodec_INTEGER.enc(hash(s)) - - - -ASN1_Codecs.BER.register_stem(BERcodec_Object) - - -class BERcodec_INTEGER(BERcodec_Object): - tag = ASN1_Class_UNIVERSAL.INTEGER - @classmethod - def enc(cls, i): - s = [] - while 1: - s.append(i&0xff) - if -127 <= i < 0: - break - if 128 <= i <= 255: - s.append(0) - i >>= 8 - if not i: - break - #s = map(chr, s) - s = bytes(s) + BER_len_enc(len(s)) + bytes([hash(cls.tag)]) - #s.reverse() - #return b"".join(s) - return s[::-1] - @classmethod - def do_dec(cls, s, context=None, safe=False): - l,s,t = cls.check_type_check_len(s) - x = 0 - if s: - if (s[0])&0x80: # negative int - x = -1 - for c in s: - x <<= 8 - x |= (c) - return cls.asn1_object(x),t - - -class BERcodec_BOOLEAN(BERcodec_INTEGER): - tag = ASN1_Class_UNIVERSAL.BOOLEAN - -class BERcodec_ENUMERATED(BERcodec_INTEGER): - tag = ASN1_Class_UNIVERSAL.ENUMERATED - -class BERcodec_NULL(BERcodec_INTEGER): - tag = ASN1_Class_UNIVERSAL.NULL - @classmethod - def enc(cls, i): - if i == 0: - return bytes([hash(cls.tag)])+b"\0" - else: - return BERcodec_INTEGER.enc(i) - -class BERcodec_SEP(BERcodec_NULL): - tag = ASN1_Class_UNIVERSAL.SEP - -class BERcodec_STRING(BERcodec_Object): - tag = ASN1_Class_UNIVERSAL.STRING - @classmethod - def enc(cls,s): - if type(s) is str: - s = s.encode('ascii') - return bytes([hash(cls.tag)])+BER_len_enc(len(s))+s - @classmethod - def do_dec(cls, s, context=None, safe=False): - l,s,t = cls.check_type_check_len(s) - return cls.tag.asn1_object(s),t - -class BERcodec_BIT_STRING(BERcodec_STRING): - tag = ASN1_Class_UNIVERSAL.BIT_STRING - -class BERcodec_PRINTABLE_STRING(BERcodec_STRING): - tag = ASN1_Class_UNIVERSAL.PRINTABLE_STRING - -class BERcodec_T61_STRING (BERcodec_STRING): - tag = ASN1_Class_UNIVERSAL.T61_STRING - -class BERcodec_IA5_STRING(BERcodec_STRING): - tag = ASN1_Class_UNIVERSAL.IA5_STRING - -class BERcodec_NUMERIC_STRING(BERcodec_STRING): - tag = ASN1_Class_UNIVERSAL.NUMERIC_STRING - -class BERcodec_VIDEOTEX_STRING(BERcodec_STRING): - tag = ASN1_Class_UNIVERSAL.VIDEOTEX_STRING - -class BERcodec_IPADDRESS(BERcodec_STRING): - tag = ASN1_Class_UNIVERSAL.IPADDRESS - - @classmethod - def enc(cls, ipaddr_ascii): - try: - s = inet_aton(ipaddr_ascii) - except Exception: - raise BER_Encoding_Error("IPv4 address could not be encoded") - return bytes([hash(cls.tag)])+BER_len_enc(len(s))+s - - @classmethod - def do_dec(cls, s, context=None, safe=False): - l,s,t = cls.check_type_check_len(s) - try: - ipaddr_ascii = inet_ntoa(s) - except Exception: - raise BER_Decoding_Error("IP address could not be decoded", decoded=obj) - return cls.asn1_object(ipaddr_ascii), t - -class BERcodec_UTC_TIME(BERcodec_STRING): - tag = ASN1_Class_UNIVERSAL.UTC_TIME - -class BERcodec_GENERALIZED_TIME(BERcodec_STRING): - tag = ASN1_Class_UNIVERSAL.GENERALIZED_TIME - -class BERcodec_TIME_TICKS(BERcodec_INTEGER): - tag = ASN1_Class_UNIVERSAL.TIME_TICKS - -class BERcodec_GAUGE32(BERcodec_INTEGER): - tag = ASN1_Class_UNIVERSAL.GAUGE32 - -class BERcodec_COUNTER32(BERcodec_INTEGER): - tag = ASN1_Class_UNIVERSAL.COUNTER32 - -class BERcodec_SEQUENCE(BERcodec_Object): - tag = ASN1_Class_UNIVERSAL.SEQUENCE - @classmethod - def enc(cls, l): - #if type(l) is not str: - if type(l) is not bytes: - l = b"".join(map(lambda x: x.enc(cls.codec), l)) - return bytes([hash(cls.tag)])+BER_len_enc(len(l))+l - @classmethod - def do_dec(cls, s, context=None, safe=False): - if context is None: - context = cls.tag.context - l,st = cls.check_type_get_len(s) # we may have len(s) < l - s,t = st[:l],st[l:] - obj = [] - while s: - try: - o,s = BERcodec_Object.dec(s, context, safe) - except BER_Decoding_Error as err: - err.remaining += t - if err.decoded is not None: - obj.append(err.decoded) - err.decoded = obj - raise - obj.append(o) - if len(st) < l: - raise BER_Decoding_Error("Not enough bytes to decode sequence", decoded=obj) - return cls.asn1_object(obj),t - -class BERcodec_SET(BERcodec_SEQUENCE): - tag = ASN1_Class_UNIVERSAL.SET - - -class BERcodec_OID(BERcodec_Object): - tag = ASN1_Class_UNIVERSAL.OID - - @classmethod - def enc(cls, oid): - if type(oid) is str: - oid = oid.encode('ascii') - lst = [int(x) for x in oid.strip(b".").split(b".")] - if len(lst) >= 2: - lst[1] += 40*lst[0] - del(lst[0]) - s = b"".join([BER_num_enc(k) for k in lst]) - return bytes([hash(cls.tag)])+BER_len_enc(len(s))+s - @classmethod - def do_dec(cls, s, context=None, safe=False): - l,s,t = cls.check_type_check_len(s) - lst = [] - while s: - l,s = BER_num_dec(s) - lst.append(l) - if (len(lst) > 0): - lst.insert(0,lst[0]//40) - lst[1] %= 40 - return cls.asn1_object(b".".join([str(k).encode('ascii') for k in lst])), t - - |