]> Cypherpunks.ru repositories - pyderasn.git/blobdiff - pyderasn.py
Initial support for CER encoding
[pyderasn.git] / pyderasn.py
index 6da6e92706e2186339505e65c7743bc64f14ce89..3533c6b9f18f46f28d9812b1dce8824b29ecfa44 100755 (executable)
@@ -352,7 +352,6 @@ Let's parse that output, human::
  (and its derivatives), ``SET``, ``SET OF``, ``UTCTime``, ``GeneralizedTime``
  could be BERed.
 
-
 .. _definedby:
 
 DEFINED BY
@@ -428,7 +427,7 @@ defines_by_path context option
 ______________________________
 
 Sometimes you either can not or do not want to explicitly set *defines*
-in the scheme. You can dynamically apply those definitions when calling
+in the schema. You can dynamically apply those definitions when calling
 ``.decode()`` method.
 
 Specify ``defines_by_path`` key in the :ref:`decode context <ctx>`. Its
@@ -550,12 +549,12 @@ _______
 Integer
 _______
 .. autoclass:: pyderasn.Integer
-   :members: __init__
+   :members: __init__, named
 
 BitString
 _________
 .. autoclass:: pyderasn.BitString
-   :members: __init__
+   :members: __init__, bit_len, named
 
 OctetString
 ___________
@@ -587,7 +586,7 @@ _____________
 PrintableString
 _______________
 .. autoclass:: pyderasn.PrintableString
-   :members: __init__
+   :members: __init__, allow_asterisk, allow_ampersand
 
 UTCTime
 _______
@@ -597,6 +596,7 @@ _______
 GeneralizedTime
 _______________
 .. autoclass:: pyderasn.GeneralizedTime
+   :members: __init__, todatetime
 
 Special types
 -------------
@@ -604,7 +604,7 @@ Special types
 Choice
 ______
 .. autoclass:: pyderasn.Choice
-   :members: __init__
+   :members: __init__, choice, value
 
 PrimitiveTypes
 ______________
@@ -643,6 +643,7 @@ Various
 
 .. autofunction:: pyderasn.abs_decode_path
 .. autofunction:: pyderasn.colonize_hex
+.. autofunction:: pyderasn.encode_cer
 .. autofunction:: pyderasn.hexenc
 .. autofunction:: pyderasn.hexdec
 .. autofunction:: pyderasn.tag_encode
@@ -661,6 +662,115 @@ Various
 .. autoclass:: pyderasn.ObjNotReady
 .. autoclass:: pyderasn.InvalidValueType
 .. autoclass:: pyderasn.BoundsError
+
+.. _cmdline:
+
+Command-line usage
+------------------
+
+You can decode DER/BER files using command line abilities::
+
+    $ python -m pyderasn --schema tests.test_crts:Certificate path/to/file
+
+If there is no schema for your file, then you can try parsing it without,
+but of course IMPLICIT tags will often make it impossible. But result is
+good enough for the certificate above::
+
+    $ python -m pyderasn path/to/file
+        0   [1,3,1604]  . >: SEQUENCE OF
+        4   [1,3,1453]  . . >: SEQUENCE OF
+        8   [0,0,   5]  . . . . >: [0] ANY
+                        . . . . . A0:03:02:01:02
+       13   [1,1,   3]  . . . . >: INTEGER 61595
+       18   [1,1,  13]  . . . . >: SEQUENCE OF
+       20   [1,1,   9]  . . . . . . >: OBJECT IDENTIFIER 1.2.840.113549.1.1.5
+       31   [1,1,   0]  . . . . . . >: NULL
+       33   [1,3, 274]  . . . . >: SEQUENCE OF
+       37   [1,1,  11]  . . . . . . >: SET OF
+       39   [1,1,   9]  . . . . . . . . >: SEQUENCE OF
+       41   [1,1,   3]  . . . . . . . . . . >: OBJECT IDENTIFIER 2.5.4.6
+       46   [1,1,   2]  . . . . . . . . . . >: PrintableString PrintableString ES
+    [...]
+     1409   [1,1,  50]  . . . . . . >: SEQUENCE OF
+     1411   [1,1,   8]  . . . . . . . . >: OBJECT IDENTIFIER 1.3.6.1.5.5.7.1.1
+     1421   [1,1,  38]  . . . . . . . . >: OCTET STRING 38 bytes
+                        . . . . . . . . . 30:24:30:22:06:08:2B:06:01:05:05:07:30:01:86:16
+                        . . . . . . . . . 68:74:74:70:3A:2F:2F:6F:63:73:70:2E:69:70:73:63
+                        . . . . . . . . . 61:2E:63:6F:6D:2F
+     1461   [1,1,  13]  . . >: SEQUENCE OF
+     1463   [1,1,   9]  . . . . >: OBJECT IDENTIFIER 1.2.840.113549.1.1.5
+     1474   [1,1,   0]  . . . . >: NULL
+     1476   [1,2, 129]  . . >: BIT STRING 1024 bits
+                        . . . 68:EE:79:97:97:DD:3B:EF:16:6A:06:F2:14:9A:6E:CD
+                        . . . 9E:12:F7:AA:83:10:BD:D1:7C:98:FA:C7:AE:D4:0E:2C
+    [...]
+
+Human readable OIDs
+___________________
+
+If you have got dictionaries with ObjectIdentifiers, like example one
+from ``tests/test_crts.py``::
+
+    stroid2name = {
+        "1.2.840.113549.1.1.1": "id-rsaEncryption",
+        "1.2.840.113549.1.1.5": "id-sha1WithRSAEncryption",
+        [...]
+        "2.5.4.10": "id-at-organizationName",
+        "2.5.4.11": "id-at-organizationalUnitName",
+    }
+
+then you can pass it to pretty printer to see human readable OIDs::
+
+    $ python -m pyderasn --oids tests.test_crts:stroid2name path/to/file
+    [...]
+       37   [1,1,  11]  . . . . . . >: SET OF
+       39   [1,1,   9]  . . . . . . . . >: SEQUENCE OF
+       41   [1,1,   3]  . . . . . . . . . . >: OBJECT IDENTIFIER id-at-countryName (2.5.4.6)
+       46   [1,1,   2]  . . . . . . . . . . >: PrintableString PrintableString ES
+       50   [1,1,  18]  . . . . . . >: SET OF
+       52   [1,1,  16]  . . . . . . . . >: SEQUENCE OF
+       54   [1,1,   3]  . . . . . . . . . . >: OBJECT IDENTIFIER id-at-stateOrProvinceName (2.5.4.8)
+       59   [1,1,   9]  . . . . . . . . . . >: PrintableString PrintableString Barcelona
+       70   [1,1,  18]  . . . . . . >: SET OF
+       72   [1,1,  16]  . . . . . . . . >: SEQUENCE OF
+       74   [1,1,   3]  . . . . . . . . . . >: OBJECT IDENTIFIER id-at-localityName (2.5.4.7)
+       79   [1,1,   9]  . . . . . . . . . . >: PrintableString PrintableString Barcelona
+    [...]
+
+Decode paths
+____________
+
+Each decoded element has so-called decode path: sequence of structure
+names it is passing during the decode process. Each element has its own
+unique path inside the whole ASN.1 tree. You can print it out with
+``--print-decode-path`` option::
+
+    $ python -m pyderasn --schema path.to:Certificate --print-decode-path path/to/file
+       0    [1,3,1604]  Certificate SEQUENCE []
+       4    [1,3,1453]   . tbsCertificate: TBSCertificate SEQUENCE [tbsCertificate]
+      10-2  [1,1,   1]   . . version: [0] EXPLICIT Version INTEGER v3 OPTIONAL [tbsCertificate:version]
+      13    [1,1,   3]   . . serialNumber: CertificateSerialNumber INTEGER 61595 [tbsCertificate:serialNumber]
+      18    [1,1,  13]   . . signature: AlgorithmIdentifier SEQUENCE [tbsCertificate:signature]
+      20    [1,1,   9]   . . . algorithm: OBJECT IDENTIFIER 1.2.840.113549.1.1.5 [tbsCertificate:signature:algorithm]
+      31    [0,0,   2]   . . . parameters: [UNIV 5] ANY OPTIONAL [tbsCertificate:signature:parameters]
+                         . . . . 05:00
+      33    [0,0, 278]   . . issuer: Name CHOICE rdnSequence [tbsCertificate:issuer]
+      33    [1,3, 274]   . . . rdnSequence: RDNSequence SEQUENCE OF [tbsCertificate:issuer:rdnSequence]
+      37    [1,1,  11]   . . . . 0: RelativeDistinguishedName SET OF [tbsCertificate:issuer:rdnSequence:0]
+      39    [1,1,   9]   . . . . . 0: AttributeTypeAndValue SEQUENCE [tbsCertificate:issuer:rdnSequence:0:0]
+      41    [1,1,   3]   . . . . . . type: AttributeType OBJECT IDENTIFIER 2.5.4.6 [tbsCertificate:issuer:rdnSequence:0:0:type]
+      46    [0,0,   4]   . . . . . . value: [UNIV 19] AttributeValue ANY [tbsCertificate:issuer:rdnSequence:0:0:value]
+                         . . . . . . . 13:02:45:53
+      46    [1,1,   2]   . . . . . . . DEFINED BY 2.5.4.6: CountryName PrintableString ES [tbsCertificate:issuer:rdnSequence:0:0:value:DEFINED BY 2.5.4.6]
+    [...]
+
+Now you can print only the specified tree, for example signature algorithm::
+
+    $ python -m pyderasn --schema path.to:Certificate --decode-path-only tbsCertificate:signature path/to/file
+      18    [1,1,  13]  AlgorithmIdentifier SEQUENCE
+      20    [1,1,   9]   . algorithm: OBJECT IDENTIFIER 1.2.840.113549.1.1.5
+      31    [0,0,   2]   . parameters: [UNIV 5] ANY OPTIONAL
+                         . . 05:00
 """
 
 from codecs import getdecoder
@@ -670,7 +780,9 @@ from collections import OrderedDict
 from copy import copy
 from datetime import datetime
 from datetime import timedelta
+from io import BytesIO
 from math import ceil
+from operator import attrgetter
 from string import ascii_letters
 from string import digits
 from sys import version_info
@@ -698,7 +810,7 @@ except ImportError:  # pragma: no cover
     def colored(what, *args, **kwargs):
         return what
 
-__version__ = "6.3"
+__version__ = "7.0"
 
 __all__ = (
     "Any",
@@ -709,6 +821,7 @@ __all__ = (
     "Choice",
     "DecodeError",
     "DecodePathDefBy",
+    "encode_cer",
     "Enumerated",
     "ExceedingData",
     "GeneralizedTime",
@@ -788,6 +901,19 @@ def fractions2float(fractions_raw):
     return float("0." + fractions_raw)
 
 
+def get_def_by_path(defines_by_path, sub_decode_path):
+    """Get define by decode path
+    """
+    for path, define in defines_by_path:
+        if len(path) != len(sub_decode_path):
+            continue
+        for p1, p2 in zip(path, sub_decode_path):
+            if (not p1 is any) and (p1 != p2):
+                break
+        else:
+            return define
+
+
 ########################################################################
 # Errors
 ########################################################################
@@ -1067,6 +1193,23 @@ def len_decode(data):
     return l, 1 + octets_num, data[1 + octets_num:]
 
 
+LEN1K = len_encode(1000)
+
+
+def write_full(writer, data):
+    """Fully write provided data
+
+    BytesIO does not guarantee that the whole data will be written at once.
+    """
+    data = memoryview(data)
+    written = 0
+    while written != len(data):
+        n = writer(data[written:])
+        if n is None:
+            raise ValueError("can not write to buf")
+        written += n
+
+
 ########################################################################
 # Base class
 ########################################################################
@@ -1077,6 +1220,22 @@ class AutoAddSlots(type):
         return type.__new__(cls, name, bases, _dict)
 
 
+BasicState = namedtuple("BasicState", (
+    "version",
+    "tag",
+    "tag_order",
+    "expl",
+    "default",
+    "optional",
+    "offset",
+    "llen",
+    "vlen",
+    "expl_lenindef",
+    "lenindef",
+    "ber_encoded",
+), **NAMEDTUPLE_KWARGS)
+
+
 @add_metaclass(AutoAddSlots)
 class Obj(object):
     """Common ASN.1 object class
@@ -1086,6 +1245,7 @@ class Obj(object):
     """
     __slots__ = (
         "tag",
+        "_tag_order",
         "_value",
         "_expl",
         "default",
@@ -1110,6 +1270,13 @@ class Obj(object):
         self._expl = getattr(self, "expl", None) if expl is None else expl
         if self.tag != self.tag_default and self._expl is not None:
             raise ValueError("implicit and explicit tags can not be set simultaneously")
+        if self.tag is None:
+            self._tag_order = None
+        else:
+            tag_class, _, tag_num = tag_decode(
+                self.tag if self._expl is None else self._expl
+            )
+            self._tag_order = (tag_class, tag_num)
         if default is not None:
             optional = True
         self.optional = optional
@@ -1149,17 +1316,27 @@ class Obj(object):
     def __setstate__(self, state):
         if state.version != __version__:
             raise ValueError("data is pickled by different PyDERASN version")
-        self.tag = self.tag_default
-        self._value = None
-        self._expl = None
-        self.default = None
-        self.optional = False
-        self.offset = 0
-        self.llen = 0
-        self.vlen = 0
-        self.expl_lenindef = False
-        self.lenindef = False
-        self.ber_encoded = False
+        self.tag = state.tag
+        self._tag_order = state.tag_order
+        self._expl = state.expl
+        self.default = state.default
+        self.optional = state.optional
+        self.offset = state.offset
+        self.llen = state.llen
+        self.vlen = state.vlen
+        self.expl_lenindef = state.expl_lenindef
+        self.lenindef = state.lenindef
+        self.ber_encoded = state.ber_encoded
+
+    @property
+    def tag_order(self):
+        """Tag's (class, number) used for DER/CER sorting
+        """
+        return self._tag_order
+
+    @property
+    def tag_order_cer(self):
+        return self.tag_order
 
     @property
     def tlen(self):
@@ -1191,8 +1368,8 @@ class Obj(object):
     def _encode(self):  # pragma: no cover
         raise NotImplementedError()
 
-    def _decode(self, tlv, offset, decode_path, ctx, tag_only):  # pragma: no cover
-        raise NotImplementedError()
+    def _decode(self, tlv, offset, decode_path, ctx, tag_only, evgen_mode):  # pragma: no cover
+        yield NotImplemented
 
     def encode(self):
         """Encode the structure
@@ -1204,6 +1381,19 @@ class Obj(object):
             return raw
         return b"".join((self._expl, len_encode(len(raw)), raw))
 
+    def encode_cer(self, writer):
+        if self._expl is not None:
+            write_full(writer, self._expl + LENINDEF)
+        if getattr(self, "der_forced", False):
+            write_full(writer, self._encode())
+        else:
+            self._encode_cer(writer)
+        if self._expl is not None:
+            write_full(writer, EOC)
+
+    def _encode_cer(self, writer):
+        write_full(writer, self._encode())
+
     def hexencode(self):
         """Do hexadecimal encoded :py:meth:`pyderasn.Obj.encode`
         """
@@ -1218,6 +1408,32 @@ class Obj(object):
             ctx=None,
             tag_only=False,
             _ctx_immutable=True,
+    ):
+        result = next(self.decode_evgen(
+            data,
+            offset,
+            leavemm,
+            decode_path,
+            ctx,
+            tag_only,
+            _ctx_immutable,
+            _evgen_mode=False,
+        ))
+        if result is None:
+            return None
+        _, obj, tail = result
+        return obj, tail
+
+    def decode_evgen(
+            self,
+            data,
+            offset=0,
+            leavemm=False,
+            decode_path=(),
+            ctx=None,
+            tag_only=False,
+            _ctx_immutable=True,
+            _evgen_mode=True,
     ):
         """Decode the data
 
@@ -1228,7 +1444,7 @@ class Obj(object):
         :param ctx: optional :ref:`context <ctx>` governing decoding process
         :param tag_only: decode only the tag, without length and contents
                          (used only in Choice and Set structures, trying to
-                         determine if tag satisfies the scheme)
+                         determine if tag satisfies the schema)
         :param _ctx_immutable: do we need to ``copy.copy()`` ``ctx``
                                before using it?
         :returns: (Obj, remaining data)
@@ -1240,17 +1456,26 @@ class Obj(object):
         elif _ctx_immutable:
             ctx = copy(ctx)
         tlv = memoryview(data)
+        if (
+                _evgen_mode and
+                get_def_by_path(ctx.get("evgen_mode_upto", ()), decode_path) is not None
+        ):
+            _evgen_mode = False
         if self._expl is None:
-            result = self._decode(
-                tlv,
-                offset,
-                decode_path=decode_path,
-                ctx=ctx,
-                tag_only=tag_only,
-            )
-            if tag_only:
-                return None
-            obj, tail = result
+            for result in self._decode(
+                    tlv,
+                    offset=offset,
+                    decode_path=decode_path,
+                    ctx=ctx,
+                    tag_only=tag_only,
+                    evgen_mode=_evgen_mode,
+            ):
+                if tag_only:
+                    yield None
+                    return
+                _decode_path, obj, tail = result
+                if not _decode_path is decode_path:
+                    yield result
         else:
             try:
                 t, tlen, lv = tag_strip(tlv)
@@ -1279,16 +1504,20 @@ class Obj(object):
                     )
                 llen, v = 1, lv[1:]
                 offset += tlen + llen
-                result = self._decode(
-                    v,
-                    offset=offset,
-                    decode_path=decode_path,
-                    ctx=ctx,
-                    tag_only=tag_only,
-                )
-                if tag_only:  # pragma: no cover
-                    return None
-                obj, tail = result
+                for result in self._decode(
+                        v,
+                        offset=offset,
+                        decode_path=decode_path,
+                        ctx=ctx,
+                        tag_only=tag_only,
+                        evgen_mode=_evgen_mode,
+                ):
+                    if tag_only:  # pragma: no cover
+                        yield None
+                        return
+                    _decode_path, obj, tail = result
+                    if not _decode_path is decode_path:
+                        yield result
                 eoc_expected, tail = tail[:EOC_LEN], tail[EOC_LEN:]
                 if eoc_expected.tobytes() != EOC:
                     raise DecodeError(
@@ -1314,16 +1543,20 @@ class Obj(object):
                         decode_path=decode_path,
                         offset=offset,
                     )
-                result = self._decode(
-                    v,
-                    offset=offset + tlen + llen,
-                    decode_path=decode_path,
-                    ctx=ctx,
-                    tag_only=tag_only,
-                )
-                if tag_only:  # pragma: no cover
-                    return None
-                obj, tail = result
+                for result in self._decode(
+                        v,
+                        offset=offset + tlen + llen,
+                        decode_path=decode_path,
+                        ctx=ctx,
+                        tag_only=tag_only,
+                        evgen_mode=_evgen_mode,
+                ):
+                    if tag_only:  # pragma: no cover
+                        yield None
+                        return
+                    _decode_path, obj, tail = result
+                    if not _decode_path is decode_path:
+                        yield result
                 if obj.tlvlen < l and not ctx.get("allow_expl_oob", False):
                     raise DecodeError(
                         "explicit tag out-of-bound, longer than data",
@@ -1331,7 +1564,7 @@ class Obj(object):
                         decode_path=decode_path,
                         offset=offset,
                     )
-        return obj, (tail if leavemm else tail.tobytes())
+        yield decode_path, obj, (tail if leavemm else tail.tobytes())
 
     def decod(self, data, offset=0, decode_path=(), ctx=None):
         """Decode the data, check that tail is empty
@@ -1452,6 +1685,14 @@ class Obj(object):
             )
 
 
+def encode_cer(obj):
+    """Encode to CER in memory
+    """
+    buf = BytesIO()
+    obj.encode_cer(buf.write)
+    return buf.getvalue()
+
+
 class DecodePathDefBy(object):
     """DEFINED BY representation inside decode path
     """
@@ -1749,20 +1990,11 @@ def pprint(
 # ASN.1 primitive types
 ########################################################################
 
-BooleanState = namedtuple("BooleanState", (
-    "version",
-    "value",
-    "tag",
-    "expl",
-    "default",
-    "optional",
-    "offset",
-    "llen",
-    "vlen",
-    "expl_lenindef",
-    "lenindef",
-    "ber_encoded",
-), **NAMEDTUPLE_KWARGS)
+BooleanState = namedtuple(
+    "BooleanState",
+    BasicState._fields + ("value",),
+    **NAMEDTUPLE_KWARGS
+)
 
 
 class Boolean(Obj):
@@ -1822,8 +2054,8 @@ class Boolean(Obj):
     def __getstate__(self):
         return BooleanState(
             __version__,
-            self._value,
             self.tag,
+            self._tag_order,
             self._expl,
             self.default,
             self.optional,
@@ -1833,21 +2065,12 @@ class Boolean(Obj):
             self.expl_lenindef,
             self.lenindef,
             self.ber_encoded,
+            self._value,
         )
 
     def __setstate__(self, state):
         super(Boolean, self).__setstate__(state)
         self._value = state.value
-        self.tag = state.tag
-        self._expl = state.expl
-        self.default = state.default
-        self.optional = state.optional
-        self.offset = state.offset
-        self.llen = state.llen
-        self.vlen = state.vlen
-        self.expl_lenindef = state.expl_lenindef
-        self.lenindef = state.lenindef
-        self.ber_encoded = state.ber_encoded
 
     def __nonzero__(self):
         self._assert_ready()
@@ -1892,7 +2115,7 @@ class Boolean(Obj):
             (b"\xFF" if self._value else b"\x00"),
         ))
 
-    def _decode(self, tlv, offset, decode_path, ctx, tag_only):
+    def _decode(self, tlv, offset, decode_path, ctx, tag_only, evgen_mode):
         try:
             t, _, lv = tag_strip(tlv)
         except DecodeError as err:
@@ -1909,7 +2132,8 @@ class Boolean(Obj):
                 offset=offset,
             )
         if tag_only:
-            return None
+            yield None
+            return
         try:
             l, _, v = len_decode(lv)
         except DecodeError as err:
@@ -1958,7 +2182,7 @@ class Boolean(Obj):
             _decoded=(offset, 1, 1),
         )
         obj.ber_encoded = ber_encoded
-        return obj, v[1:]
+        yield decode_path, obj, v[1:]
 
     def __repr__(self):
         return pp_console_row(next(self.pps()))
@@ -1990,23 +2214,11 @@ class Boolean(Obj):
             yield pp
 
 
-IntegerState = namedtuple("IntegerState", (
-    "version",
-    "specs",
-    "value",
-    "bound_min",
-    "bound_max",
-    "tag",
-    "expl",
-    "default",
-    "optional",
-    "offset",
-    "llen",
-    "vlen",
-    "expl_lenindef",
-    "lenindef",
-    "ber_encoded",
-), **NAMEDTUPLE_KWARGS)
+IntegerState = namedtuple(
+    "IntegerState",
+    BasicState._fields + ("specs", "value", "bound_min", "bound_max"),
+    **NAMEDTUPLE_KWARGS
+)
 
 
 class Integer(Obj):
@@ -2113,11 +2325,8 @@ class Integer(Obj):
     def __getstate__(self):
         return IntegerState(
             __version__,
-            self.specs,
-            self._value,
-            self._bound_min,
-            self._bound_max,
             self.tag,
+            self._tag_order,
             self._expl,
             self.default,
             self.optional,
@@ -2127,6 +2336,10 @@ class Integer(Obj):
             self.expl_lenindef,
             self.lenindef,
             self.ber_encoded,
+            self.specs,
+            self._value,
+            self._bound_min,
+            self._bound_max,
         )
 
     def __setstate__(self, state):
@@ -2135,16 +2348,6 @@ class Integer(Obj):
         self._value = state.value
         self._bound_min = state.bound_min
         self._bound_max = state.bound_max
-        self.tag = state.tag
-        self._expl = state.expl
-        self.default = state.default
-        self.optional = state.optional
-        self.offset = state.offset
-        self.llen = state.llen
-        self.vlen = state.vlen
-        self.expl_lenindef = state.expl_lenindef
-        self.lenindef = state.lenindef
-        self.ber_encoded = state.ber_encoded
 
     def __int__(self):
         self._assert_ready()
@@ -2174,6 +2377,8 @@ class Integer(Obj):
 
     @property
     def named(self):
+        """Return named representation (if exists) of the value
+        """
         for name, value in iteritems(self.specs):
             if value == self._value:
                 return name
@@ -2240,7 +2445,7 @@ class Integer(Obj):
                     break
         return b"".join((self.tag, len_encode(len(octets)), octets))
 
-    def _decode(self, tlv, offset, decode_path, ctx, tag_only):
+    def _decode(self, tlv, offset, decode_path, ctx, tag_only, evgen_mode):
         try:
             t, _, lv = tag_strip(tlv)
         except DecodeError as err:
@@ -2257,7 +2462,8 @@ class Integer(Obj):
                 offset=offset,
             )
         if tag_only:
-            return None
+            yield None
+            return
         try:
             l, llen, v = len_decode(lv)
         except DecodeError as err:
@@ -2328,7 +2534,7 @@ class Integer(Obj):
                 decode_path=decode_path,
                 offset=offset,
             )
-        return obj, tail
+        yield decode_path, obj, tail
 
     def __repr__(self):
         return pp_console_row(next(self.pps()))
@@ -2359,23 +2565,11 @@ class Integer(Obj):
             yield pp
 
 
-BitStringState = namedtuple("BitStringState", (
-    "version",
-    "specs",
-    "value",
-    "tag",
-    "expl",
-    "default",
-    "optional",
-    "offset",
-    "llen",
-    "vlen",
-    "expl_lenindef",
-    "lenindef",
-    "ber_encoded",
-    "tag_constructed",
-    "defined",
-), **NAMEDTUPLE_KWARGS)
+BitStringState = namedtuple(
+    "BitStringState",
+    BasicState._fields + ("specs", "value", "tag_constructed", "defined"),
+    **NAMEDTUPLE_KWARGS
+)
 
 
 class BitString(Obj):
@@ -2533,9 +2727,8 @@ class BitString(Obj):
     def __getstate__(self):
         return BitStringState(
             __version__,
-            self.specs,
-            self._value,
             self.tag,
+            self._tag_order,
             self._expl,
             self.default,
             self.optional,
@@ -2545,6 +2738,8 @@ class BitString(Obj):
             self.expl_lenindef,
             self.lenindef,
             self.ber_encoded,
+            self.specs,
+            self._value,
             self.tag_constructed,
             self.defined,
         )
@@ -2553,16 +2748,6 @@ class BitString(Obj):
         super(BitString, self).__setstate__(state)
         self.specs = state.specs
         self._value = state.value
-        self.tag = state.tag
-        self._expl = state.expl
-        self.default = state.default
-        self.optional = state.optional
-        self.offset = state.offset
-        self.llen = state.llen
-        self.vlen = state.vlen
-        self.expl_lenindef = state.expl_lenindef
-        self.lenindef = state.lenindef
-        self.ber_encoded = state.ber_encoded
         self.tag_constructed = state.tag_constructed
         self.defined = state.defined
 
@@ -2573,6 +2758,8 @@ class BitString(Obj):
 
     @property
     def bit_len(self):
+        """Returns number of bits in the string
+        """
         self._assert_ready()
         return self._value[0]
 
@@ -2593,6 +2780,10 @@ class BitString(Obj):
 
     @property
     def named(self):
+        """Named representation (if exists) of the bits
+
+        :returns: [str(name), ...]
+        """
         return [name for name, bit in iteritems(self.specs) if self[bit]]
 
     def __call__(
@@ -2638,7 +2829,31 @@ class BitString(Obj):
             octets,
         ))
 
-    def _decode(self, tlv, offset, decode_path, ctx, tag_only):
+    def _encode_cer(self, writer):
+        bit_len, octets = self._value
+        if len(octets) + 1 <= 1000:
+            write_full(writer, self._encode())
+            return
+        write_full(writer, self.tag_constructed)
+        write_full(writer, LENINDEF)
+        for offset in six_xrange(0, (len(octets) // 999) * 999, 999):
+            write_full(writer, b"".join((
+                BitString.tag_default,
+                LEN1K,
+                int2byte(0),
+                octets[offset:offset + 999],
+            )))
+        tail = octets[offset+999:]
+        if len(tail) > 0:
+            tail = int2byte((8 - bit_len % 8) % 8) + tail
+            write_full(writer, b"".join((
+                BitString.tag_default,
+                len_encode(len(tail)),
+                tail,
+            )))
+        write_full(writer, EOC)
+
+    def _decode(self, tlv, offset, decode_path, ctx, tag_only, evgen_mode):
         try:
             t, tlen, lv = tag_strip(tlv)
         except DecodeError as err:
@@ -2650,7 +2865,8 @@ class BitString(Obj):
             )
         if t == self.tag:
             if tag_only:  # pragma: no cover
-                return None
+                yield None
+                return
             try:
                 l, llen, v = len_decode(lv)
             except DecodeError as err:
@@ -2697,8 +2913,9 @@ class BitString(Obj):
                     offset=offset,
                 )
             v, tail = v[:l], v[l:]
+            bit_len = (len(v) - 1) * 8 - pad_size
             obj = self.__class__(
-                value=((len(v) - 1) * 8 - pad_size, v[1:].tobytes()),
+                value=None if evgen_mode else (bit_len, v[1:].tobytes()),
                 impl=self.tag,
                 expl=self._expl,
                 default=self.default,
@@ -2706,7 +2923,10 @@ class BitString(Obj):
                 _specs=self.specs,
                 _decoded=(offset, llen, l),
             )
-            return obj, tail
+            if evgen_mode:
+                obj._value = (bit_len, None)
+            yield decode_path, obj, tail
+            return
         if t != self.tag_constructed:
             raise TagMismatch(
                 klass=self.__class__,
@@ -2721,7 +2941,8 @@ class BitString(Obj):
                 offset=offset,
             )
         if tag_only:  # pragma: no cover
-            return None
+            yield None
+            return
         lenindef = False
         try:
             l, llen, v = len_decode(lv)
@@ -2768,22 +2989,34 @@ class BitString(Obj):
                     )
             sub_decode_path = decode_path + (str(len(chunks)),)
             try:
-                chunk, v_tail = BitString().decode(
-                    v,
-                    offset=sub_offset,
-                    decode_path=sub_decode_path,
-                    leavemm=True,
-                    ctx=ctx,
-                    _ctx_immutable=False,
-                )
-            except TagMismatch:
-                raise DecodeError(
-                    "expected BitString encoded chunk",
-                    klass=self.__class__,
-                    decode_path=sub_decode_path,
-                    offset=sub_offset,
-                )
-            chunks.append(chunk)
+                if evgen_mode:
+                    for _decode_path, chunk, v_tail in BitString().decode_evgen(
+                            v,
+                            offset=sub_offset,
+                            decode_path=sub_decode_path,
+                            leavemm=True,
+                            ctx=ctx,
+                            _ctx_immutable=False,
+                    ):
+                        yield _decode_path, chunk, v_tail
+                else:
+                    _, chunk, v_tail = next(BitString().decode_evgen(
+                        v,
+                        offset=sub_offset,
+                        decode_path=sub_decode_path,
+                        leavemm=True,
+                        ctx=ctx,
+                        _ctx_immutable=False,
+                        _evgen_mode=False,
+                    ))
+            except TagMismatch:
+                raise DecodeError(
+                    "expected BitString encoded chunk",
+                    klass=self.__class__,
+                    decode_path=sub_decode_path,
+                    offset=sub_offset,
+                )
+            chunks.append(chunk)
             sub_offset += chunk.tlvlen
             vlen += chunk.tlvlen
             v = v_tail
@@ -2804,13 +3037,15 @@ class BitString(Obj):
                     decode_path=decode_path + (str(chunk_i),),
                     offset=chunk.offset,
                 )
-            values.append(bytes(chunk))
+            if not evgen_mode:
+                values.append(bytes(chunk))
             bit_len += chunk.bit_len
         chunk_last = chunks[-1]
-        values.append(bytes(chunk_last))
+        if not evgen_mode:
+            values.append(bytes(chunk_last))
         bit_len += chunk_last.bit_len
         obj = self.__class__(
-            value=(bit_len, b"".join(values)),
+            value=None if evgen_mode else (bit_len, b"".join(values)),
             impl=self.tag,
             expl=self._expl,
             default=self.default,
@@ -2818,9 +3053,11 @@ class BitString(Obj):
             _specs=self.specs,
             _decoded=(offset, llen, vlen + (EOC_LEN if lenindef else 0)),
         )
+        if evgen_mode:
+            obj._value = (bit_len, None)
         obj.lenindef = lenindef
         obj.ber_encoded = True
-        return obj, (v[EOC_LEN:] if lenindef else v)
+        yield decode_path, obj, (v[EOC_LEN:] if lenindef else v)
 
     def __repr__(self):
         return pp_console_row(next(self.pps()))
@@ -2831,7 +3068,7 @@ class BitString(Obj):
         if self.ready:
             bit_len, blob = self._value
             value = "%d bits" % bit_len
-            if len(self.specs) > 0:
+            if len(self.specs) > 0 and blob is not None:
                 blob = tuple(self.named)
         yield _pp(
             obj=self,
@@ -2866,24 +3103,17 @@ class BitString(Obj):
             yield pp
 
 
-OctetStringState = namedtuple("OctetStringState", (
-    "version",
-    "value",
-    "bound_min",
-    "bound_max",
-    "tag",
-    "expl",
-    "default",
-    "optional",
-    "offset",
-    "llen",
-    "vlen",
-    "expl_lenindef",
-    "lenindef",
-    "ber_encoded",
-    "tag_constructed",
-    "defined",
-), **NAMEDTUPLE_KWARGS)
+OctetStringState = namedtuple(
+    "OctetStringState",
+    BasicState._fields + (
+        "value",
+        "bound_min",
+        "bound_max",
+        "tag_constructed",
+        "defined",
+    ),
+    **NAMEDTUPLE_KWARGS
+)
 
 
 class OctetString(Obj):
@@ -2913,6 +3143,7 @@ class OctetString(Obj):
     __slots__ = ("tag_constructed", "_bound_min", "_bound_max", "defined")
     tag_default = tag_encode(4)
     asn1_type_name = "OCTET STRING"
+    evgen_mode_skip_value = True
 
     def __init__(
             self,
@@ -2979,10 +3210,8 @@ class OctetString(Obj):
     def __getstate__(self):
         return OctetStringState(
             __version__,
-            self._value,
-            self._bound_min,
-            self._bound_max,
             self.tag,
+            self._tag_order,
             self._expl,
             self.default,
             self.optional,
@@ -2992,6 +3221,9 @@ class OctetString(Obj):
             self.expl_lenindef,
             self.lenindef,
             self.ber_encoded,
+            self._value,
+            self._bound_min,
+            self._bound_max,
             self.tag_constructed,
             self.defined,
         )
@@ -3001,16 +3233,6 @@ class OctetString(Obj):
         self._value = state.value
         self._bound_min = state.bound_min
         self._bound_max = state.bound_max
-        self.tag = state.tag
-        self._expl = state.expl
-        self.default = state.default
-        self.optional = state.optional
-        self.offset = state.offset
-        self.llen = state.llen
-        self.vlen = state.vlen
-        self.expl_lenindef = state.expl_lenindef
-        self.lenindef = state.lenindef
-        self.ber_encoded = state.ber_encoded
         self.tag_constructed = state.tag_constructed
         self.defined = state.defined
 
@@ -3061,7 +3283,29 @@ class OctetString(Obj):
             self._value,
         ))
 
-    def _decode(self, tlv, offset, decode_path, ctx, tag_only):
+    def _encode_cer(self, writer):
+        octets = self._value
+        if len(octets) <= 1000:
+            write_full(writer, self._encode())
+            return
+        write_full(writer, self.tag_constructed)
+        write_full(writer, LENINDEF)
+        for offset in six_xrange(0, (len(octets) // 1000) * 1000, 1000):
+            write_full(writer, b"".join((
+                OctetString.tag_default,
+                LEN1K,
+                octets[offset:offset + 1000],
+            )))
+        tail = octets[offset+1000:]
+        if len(tail) > 0:
+            write_full(writer, b"".join((
+                OctetString.tag_default,
+                len_encode(len(tail)),
+                tail,
+            )))
+        write_full(writer, EOC)
+
+    def _decode(self, tlv, offset, decode_path, ctx, tag_only, evgen_mode):
         try:
             t, tlen, lv = tag_strip(tlv)
         except DecodeError as err:
@@ -3073,7 +3317,8 @@ class OctetString(Obj):
             )
         if t == self.tag:
             if tag_only:
-                return None
+                yield None
+                return
             try:
                 l, llen, v = len_decode(lv)
             except DecodeError as err:
@@ -3091,9 +3336,19 @@ class OctetString(Obj):
                     offset=offset,
                 )
             v, tail = v[:l], v[l:]
+            if evgen_mode and not self._bound_min <= len(v) <= self._bound_max:
+                raise DecodeError(
+                    msg=str(BoundsError(self._bound_min, len(v), self._bound_max)),
+                    klass=self.__class__,
+                    decode_path=decode_path,
+                    offset=offset,
+                )
             try:
                 obj = self.__class__(
-                    value=v.tobytes(),
+                    value=(
+                        None if (evgen_mode and self.evgen_mode_skip_value)
+                        else v.tobytes()
+                    ),
                     bounds=(self._bound_min, self._bound_max),
                     impl=self.tag,
                     expl=self._expl,
@@ -3116,7 +3371,8 @@ class OctetString(Obj):
                     decode_path=decode_path,
                     offset=offset,
                 )
-            return obj, tail
+            yield decode_path, obj, tail
+            return
         if t != self.tag_constructed:
             raise TagMismatch(
                 klass=self.__class__,
@@ -3131,7 +3387,8 @@ class OctetString(Obj):
                 offset=offset,
             )
         if tag_only:
-            return None
+            yield None
+            return
         lenindef = False
         try:
             l, llen, v = len_decode(lv)
@@ -3153,8 +3410,10 @@ class OctetString(Obj):
                 offset=offset,
             )
         chunks = []
+        chunks_count = 0
         sub_offset = offset + tlen + llen
         vlen = 0
+        payload_len = 0
         while True:
             if lenindef:
                 if v[:EOC_LEN].tobytes() == EOC:
@@ -3169,16 +3428,33 @@ class OctetString(Obj):
                         decode_path=decode_path + (str(len(chunks) - 1),),
                         offset=chunks[-1].offset,
                     )
-            sub_decode_path = decode_path + (str(len(chunks)),)
             try:
-                chunk, v_tail = OctetString().decode(
-                    v,
-                    offset=sub_offset,
-                    decode_path=sub_decode_path,
-                    leavemm=True,
-                    ctx=ctx,
-                    _ctx_immutable=False,
-                )
+                if evgen_mode:
+                    sub_decode_path = decode_path + (str(chunks_count),)
+                    for _decode_path, chunk, v_tail in OctetString().decode_evgen(
+                            v,
+                            offset=sub_offset,
+                            decode_path=sub_decode_path,
+                            leavemm=True,
+                            ctx=ctx,
+                            _ctx_immutable=False,
+                    ):
+                        yield _decode_path, chunk, v_tail
+                        if not chunk.ber_encoded:
+                            payload_len += chunk.vlen
+                    chunks_count += 1
+                else:
+                    sub_decode_path = decode_path + (str(len(chunks)),)
+                    _, chunk, v_tail = next(OctetString().decode_evgen(
+                        v,
+                        offset=sub_offset,
+                        decode_path=sub_decode_path,
+                        leavemm=True,
+                        ctx=ctx,
+                        _ctx_immutable=False,
+                        _evgen_mode=False,
+                    ))
+                    chunks.append(chunk)
             except TagMismatch:
                 raise DecodeError(
                     "expected OctetString encoded chunk",
@@ -3186,13 +3462,22 @@ class OctetString(Obj):
                     decode_path=sub_decode_path,
                     offset=sub_offset,
                 )
-            chunks.append(chunk)
             sub_offset += chunk.tlvlen
             vlen += chunk.tlvlen
             v = v_tail
+        if evgen_mode and not self._bound_min <= payload_len <= self._bound_max:
+            raise DecodeError(
+                msg=str(BoundsError(self._bound_min, payload_len, self._bound_max)),
+                klass=self.__class__,
+                decode_path=decode_path,
+                offset=offset,
+            )
         try:
             obj = self.__class__(
-                value=b"".join(bytes(chunk) for chunk in chunks),
+                value=(
+                    None if evgen_mode else
+                    b"".join(bytes(chunk) for chunk in chunks)
+                ),
                 bounds=(self._bound_min, self._bound_max),
                 impl=self.tag,
                 expl=self._expl,
@@ -3217,7 +3502,7 @@ class OctetString(Obj):
             )
         obj.lenindef = lenindef
         obj.ber_encoded = True
-        return obj, (v[EOC_LEN:] if lenindef else v)
+        yield decode_path, obj, (v[EOC_LEN:] if lenindef else v)
 
     def __repr__(self):
         return pp_console_row(next(self.pps()))
@@ -3256,19 +3541,7 @@ class OctetString(Obj):
             yield pp
 
 
-NullState = namedtuple("NullState", (
-    "version",
-    "tag",
-    "expl",
-    "default",
-    "optional",
-    "offset",
-    "llen",
-    "vlen",
-    "expl_lenindef",
-    "lenindef",
-    "ber_encoded",
-), **NAMEDTUPLE_KWARGS)
+NullState = namedtuple("NullState", BasicState._fields, **NAMEDTUPLE_KWARGS)
 
 
 class Null(Obj):
@@ -3307,6 +3580,7 @@ class Null(Obj):
         return NullState(
             __version__,
             self.tag,
+            self._tag_order,
             self._expl,
             self.default,
             self.optional,
@@ -3318,19 +3592,6 @@ class Null(Obj):
             self.ber_encoded,
         )
 
-    def __setstate__(self, state):
-        super(Null, self).__setstate__(state)
-        self.tag = state.tag
-        self._expl = state.expl
-        self.default = state.default
-        self.optional = state.optional
-        self.offset = state.offset
-        self.llen = state.llen
-        self.vlen = state.vlen
-        self.expl_lenindef = state.expl_lenindef
-        self.lenindef = state.lenindef
-        self.ber_encoded = state.ber_encoded
-
     def __eq__(self, their):
         if not issubclass(their.__class__, Null):
             return False
@@ -3355,7 +3616,7 @@ class Null(Obj):
     def _encode(self):
         return self.tag + len_encode(0)
 
-    def _decode(self, tlv, offset, decode_path, ctx, tag_only):
+    def _decode(self, tlv, offset, decode_path, ctx, tag_only, evgen_mode):
         try:
             t, _, lv = tag_strip(tlv)
         except DecodeError as err:
@@ -3372,7 +3633,8 @@ class Null(Obj):
                 offset=offset,
             )
         if tag_only:  # pragma: no cover
-            return None
+            yield None
+            return
         try:
             l, _, v = len_decode(lv)
         except DecodeError as err:
@@ -3395,7 +3657,7 @@ class Null(Obj):
             optional=self.optional,
             _decoded=(offset, 1, 0),
         )
-        return obj, v
+        yield decode_path, obj, v
 
     def __repr__(self):
         return pp_console_row(next(self.pps()))
@@ -3424,21 +3686,11 @@ class Null(Obj):
             yield pp
 
 
-ObjectIdentifierState = namedtuple("ObjectIdentifierState", (
-    "version",
-    "value",
-    "tag",
-    "expl",
-    "default",
-    "optional",
-    "offset",
-    "llen",
-    "vlen",
-    "expl_lenindef",
-    "lenindef",
-    "ber_encoded",
-    "defines",
-), **NAMEDTUPLE_KWARGS)
+ObjectIdentifierState = namedtuple(
+    "ObjectIdentifierState",
+    BasicState._fields + ("value", "defines"),
+    **NAMEDTUPLE_KWARGS
+)
 
 
 class ObjectIdentifier(Obj):
@@ -3544,8 +3796,8 @@ class ObjectIdentifier(Obj):
     def __getstate__(self):
         return ObjectIdentifierState(
             __version__,
-            self._value,
             self.tag,
+            self._tag_order,
             self._expl,
             self.default,
             self.optional,
@@ -3555,22 +3807,13 @@ class ObjectIdentifier(Obj):
             self.expl_lenindef,
             self.lenindef,
             self.ber_encoded,
+            self._value,
             self.defines,
         )
 
     def __setstate__(self, state):
         super(ObjectIdentifier, self).__setstate__(state)
         self._value = state.value
-        self.tag = state.tag
-        self._expl = state.expl
-        self.default = state.default
-        self.optional = state.optional
-        self.offset = state.offset
-        self.llen = state.llen
-        self.vlen = state.vlen
-        self.expl_lenindef = state.expl_lenindef
-        self.lenindef = state.lenindef
-        self.ber_encoded = state.ber_encoded
         self.defines = state.defines
 
     def __iter__(self):
@@ -3639,7 +3882,7 @@ class ObjectIdentifier(Obj):
         v = b"".join(octets)
         return b"".join((self.tag, len_encode(len(v)), v))
 
-    def _decode(self, tlv, offset, decode_path, ctx, tag_only):
+    def _decode(self, tlv, offset, decode_path, ctx, tag_only, evgen_mode):
         try:
             t, _, lv = tag_strip(tlv)
         except DecodeError as err:
@@ -3656,7 +3899,8 @@ class ObjectIdentifier(Obj):
                 offset=offset,
             )
         if tag_only:  # pragma: no cover
-            return None
+            yield None
+            return
         try:
             l, llen, v = len_decode(lv)
         except DecodeError as err:
@@ -3726,7 +3970,7 @@ class ObjectIdentifier(Obj):
         )
         if ber_encoded:
             obj.ber_encoded = True
-        return obj, tail
+        yield decode_path, obj, tail
 
     def __repr__(self):
         return pp_console_row(next(self.pps()))
@@ -4210,6 +4454,7 @@ class UTCTime(VisibleString):
     tag_default = tag_encode(23)
     encoding = "ascii"
     asn1_type_name = "UTCTime"
+    evgen_mode_skip_value = False
 
     def __init__(
             self,
@@ -4380,6 +4625,9 @@ class UTCTime(VisibleString):
         value = self._encode_time()
         return b"".join((self.tag, len_encode(len(value)), value))
 
+    def _encode_cer(self, writer):
+        write_full(writer, self._encode())
+
     def todatetime(self):
         return self._value
 
@@ -4575,21 +4823,11 @@ class BMPString(CommonString):
     asn1_type_name = "BMPString"
 
 
-ChoiceState = namedtuple("ChoiceState", (
-    "version",
-    "specs",
-    "value",
-    "tag",
-    "expl",
-    "default",
-    "optional",
-    "offset",
-    "llen",
-    "vlen",
-    "expl_lenindef",
-    "lenindef",
-    "ber_encoded",
-), **NAMEDTUPLE_KWARGS)
+ChoiceState = namedtuple(
+    "ChoiceState",
+    BasicState._fields + ("specs", "value",),
+    **NAMEDTUPLE_KWARGS
+)
 
 
 class Choice(Obj):
@@ -4666,6 +4904,9 @@ class Choice(Obj):
             self.default = default_obj
             if value is None:
                 self._value = copy(default_obj._value)
+        if self._expl is not None:
+            tag_class, _, tag_num = tag_decode(self._expl)
+            self._tag_order = (tag_class, tag_num)
 
     def _value_sanitize(self, value):
         if (value.__class__ == tuple) and len(value) == 2:
@@ -4694,9 +4935,8 @@ class Choice(Obj):
     def __getstate__(self):
         return ChoiceState(
             __version__,
-            self.specs,
-            copy(self._value),
             self.tag,
+            self._tag_order,
             self._expl,
             self.default,
             self.optional,
@@ -4706,21 +4946,14 @@ class Choice(Obj):
             self.expl_lenindef,
             self.lenindef,
             self.ber_encoded,
+            self.specs,
+            copy(self._value),
         )
 
     def __setstate__(self, state):
         super(Choice, self).__setstate__(state)
         self.specs = state.specs
         self._value = state.value
-        self._expl = state.expl
-        self.default = state.default
-        self.optional = state.optional
-        self.offset = state.offset
-        self.llen = state.llen
-        self.vlen = state.vlen
-        self.expl_lenindef = state.expl_lenindef
-        self.lenindef = state.lenindef
-        self.ber_encoded = state.ber_encoded
 
     def __eq__(self, their):
         if (their.__class__ == tuple) and len(their) == 2:
@@ -4749,14 +4982,27 @@ class Choice(Obj):
 
     @property
     def choice(self):
+        """Name of the choice
+        """
         self._assert_ready()
         return self._value[0]
 
     @property
     def value(self):
+        """Value of underlying choice
+        """
         self._assert_ready()
         return self._value[1]
 
+    @property
+    def tag_order(self):
+        self._assert_ready()
+        return self._value[1].tag_order if self._tag_order is None else self._tag_order
+
+    @property
+    def tag_order_cer(self):
+        return min(v.tag_order_cer for v in itervalues(self.specs))
+
     def __getitem__(self, key):
         if key not in self.specs:
             raise ObjUnknown(key)
@@ -4787,7 +5033,11 @@ class Choice(Obj):
         self._assert_ready()
         return self._value[1].encode()
 
-    def _decode(self, tlv, offset, decode_path, ctx, tag_only):
+    def _encode_cer(self, writer):
+        self._assert_ready()
+        self._value[1].encode_cer(writer)
+
+    def _decode(self, tlv, offset, decode_path, ctx, tag_only, evgen_mode):
         for choice, spec in iteritems(self.specs):
             sub_decode_path = decode_path + (choice,)
             try:
@@ -4810,15 +5060,28 @@ class Choice(Obj):
                 offset=offset,
             )
         if tag_only:  # pragma: no cover
-            return None
-        value, tail = spec.decode(
-            tlv,
-            offset=offset,
-            leavemm=True,
-            decode_path=sub_decode_path,
-            ctx=ctx,
-            _ctx_immutable=False,
-        )
+            yield None
+            return
+        if evgen_mode:
+            for _decode_path, value, tail in spec.decode_evgen(
+                    tlv,
+                    offset=offset,
+                    leavemm=True,
+                    decode_path=sub_decode_path,
+                    ctx=ctx,
+                    _ctx_immutable=False,
+            ):
+                yield _decode_path, value, tail
+        else:
+            _, value, tail = next(spec.decode_evgen(
+                tlv,
+                offset=offset,
+                leavemm=True,
+                decode_path=sub_decode_path,
+                ctx=ctx,
+                _ctx_immutable=False,
+                _evgen_mode=False,
+            ))
         obj = self.__class__(
             schema=self.specs,
             expl=self._expl,
@@ -4827,7 +5090,7 @@ class Choice(Obj):
             _decoded=(offset, 0, value.fulllen),
         )
         obj._value = (choice, value)
-        return obj, tail
+        yield decode_path, obj, tail
 
     def __repr__(self):
         value = pp_console_row(next(self.pps()))
@@ -4894,27 +5157,18 @@ class PrimitiveTypes(Choice):
     ))
 
 
-AnyState = namedtuple("AnyState", (
-    "version",
-    "value",
-    "tag",
-    "expl",
-    "optional",
-    "offset",
-    "llen",
-    "vlen",
-    "expl_lenindef",
-    "lenindef",
-    "ber_encoded",
-    "defined",
-), **NAMEDTUPLE_KWARGS)
+AnyState = namedtuple(
+    "AnyState",
+    BasicState._fields + ("value", "defined"),
+    **NAMEDTUPLE_KWARGS
+)
 
 
 class Any(Obj):
     """``ANY`` special type
 
     >>> Any(Integer(-123))
-    ANY 020185
+    ANY INTEGER -123 (0X:7B)
     >>> a = Any(OctetString(b"hello world").encode())
     ANY 040b68656c6c6f20776f726c64
     >>> hexenc(bytes(a))
@@ -4934,28 +5188,47 @@ class Any(Obj):
         """
         :param value: set the value. Either any kind of pyderasn's
                       **ready** object, or bytes. Pay attention that
-                      **no** validation is performed is raw binary value
-                      is valid TLV
+                      **no** validation is performed if raw binary value
+                      is valid TLV, except just tag decoding
         :param bytes expl: override default tag with ``EXPLICIT`` one
         :param bool optional: is object ``OPTIONAL`` in sequence
         """
         super(Any, self).__init__(None, expl, None, optional, _decoded)
-        self._value = None if value is None else self._value_sanitize(value)
+        if value is None:
+            self._value = None
+        else:
+            value = self._value_sanitize(value)
+            self._value = value
+            if self._expl is None:
+                if value.__class__ == binary_type:
+                    tag_class, _, tag_num = tag_decode(tag_strip(value)[0])
+                else:
+                    tag_class, tag_num = value.tag_order
+            else:
+                tag_class, _, tag_num = tag_decode(self._expl)
+            self._tag_order = (tag_class, tag_num)
         self.defined = None
 
     def _value_sanitize(self, value):
         if value.__class__ == binary_type:
+            if len(value) == 0:
+                raise ValueError("Any value can not be empty")
             return value
         if isinstance(value, self.__class__):
             return value._value
-        if isinstance(value, Obj):
-            return value.encode()
-        raise InvalidValueType((self.__class__, Obj, binary_type))
+        if not isinstance(value, Obj):
+            raise InvalidValueType((self.__class__, Obj, binary_type))
+        return value
 
     @property
     def ready(self):
         return self._value is not None
 
+    @property
+    def tag_order(self):
+        self._assert_ready()
+        return self._tag_order
+
     @property
     def bered(self):
         if self.expl_lenindef or self.lenindef:
@@ -4967,9 +5240,10 @@ class Any(Obj):
     def __getstate__(self):
         return AnyState(
             __version__,
-            self._value,
             self.tag,
+            self._tag_order,
             self._expl,
+            None,
             self.optional,
             self.offset,
             self.llen,
@@ -4977,28 +5251,24 @@ class Any(Obj):
             self.expl_lenindef,
             self.lenindef,
             self.ber_encoded,
+            self._value,
             self.defined,
         )
 
     def __setstate__(self, state):
         super(Any, self).__setstate__(state)
         self._value = state.value
-        self.tag = state.tag
-        self._expl = state.expl
-        self.optional = state.optional
-        self.offset = state.offset
-        self.llen = state.llen
-        self.vlen = state.vlen
-        self.expl_lenindef = state.expl_lenindef
-        self.lenindef = state.lenindef
-        self.ber_encoded = state.ber_encoded
         self.defined = state.defined
 
     def __eq__(self, their):
         if their.__class__ == binary_type:
-            return self._value == their
+            if self._value.__class__ == binary_type:
+                return self._value == their
+            return self._value.encode() == their
         if issubclass(their.__class__, Any):
-            return self._value == their._value
+            if self.ready and their.ready:
+                return bytes(self) == bytes(their)
+            return self.ready == their.ready
         return False
 
     def __call__(
@@ -5015,7 +5285,10 @@ class Any(Obj):
 
     def __bytes__(self):
         self._assert_ready()
-        return self._value
+        value = self._value
+        if value.__class__ == binary_type:
+            return value
+        return self._value.encode()
 
     @property
     def tlen(self):
@@ -5023,9 +5296,20 @@ class Any(Obj):
 
     def _encode(self):
         self._assert_ready()
-        return self._value
+        value = self._value
+        if value.__class__ == binary_type:
+            return value
+        return value.encode()
 
-    def _decode(self, tlv, offset, decode_path, ctx, tag_only):
+    def _encode_cer(self, writer):
+        self._assert_ready()
+        value = self._value
+        if value.__class__ == binary_type:
+            write_full(writer, value)
+        else:
+            value.encode_cer(writer)
+
+    def _decode(self, tlv, offset, decode_path, ctx, tag_only, evgen_mode):
         try:
             t, tlen, lv = tag_strip(tlv)
         except DecodeError as err:
@@ -5062,14 +5346,15 @@ class Any(Obj):
                 chunk_i += 1
             tlvlen = tlen + llen + vlen + EOC_LEN
             obj = self.__class__(
-                value=tlv[:tlvlen].tobytes(),
+                value=None if evgen_mode else tlv[:tlvlen].tobytes(),
                 expl=self._expl,
                 optional=self.optional,
                 _decoded=(offset, 0, tlvlen),
             )
             obj.lenindef = True
             obj.tag = t.tobytes()
-            return obj, v[EOC_LEN:]
+            yield decode_path, obj, v[EOC_LEN:]
+            return
         except DecodeError as err:
             raise err.__class__(
                 msg=err.msg,
@@ -5087,24 +5372,32 @@ class Any(Obj):
         tlvlen = tlen + llen + l
         v, tail = tlv[:tlvlen], v[l:]
         obj = self.__class__(
-            value=v.tobytes(),
+            value=None if evgen_mode else v.tobytes(),
             expl=self._expl,
             optional=self.optional,
             _decoded=(offset, 0, tlvlen),
         )
         obj.tag = t.tobytes()
-        return obj, tail
+        yield decode_path, obj, tail
 
     def __repr__(self):
         return pp_console_row(next(self.pps()))
 
     def pps(self, decode_path=()):
+        value = self._value
+        if value is None:
+            pass
+        elif value.__class__ == binary_type:
+            value = None
+        else:
+            value = repr(value)
         yield _pp(
             obj=self,
             asn1_type_name=self.asn1_type_name,
             obj_name=self.__class__.__name__,
             decode_path=decode_path,
-            blob=self._value if self.ready else None,
+            value=value,
+            blob=self._value if self._value.__class__ == binary_type else None,
             optional=self.optional,
             default=self == self.default,
             impl=None if self.tag == self.tag_default else tag_decode(self.tag),
@@ -5172,21 +5465,11 @@ def abs_decode_path(decode_path, rel_path):
     return decode_path + rel_path
 
 
-SequenceState = namedtuple("SequenceState", (
-    "version",
-    "specs",
-    "value",
-    "tag",
-    "expl",
-    "default",
-    "optional",
-    "offset",
-    "llen",
-    "vlen",
-    "expl_lenindef",
-    "lenindef",
-    "ber_encoded",
-), **NAMEDTUPLE_KWARGS)
+SequenceState = namedtuple(
+    "SequenceState",
+    BasicState._fields + ("specs", "value",),
+    **NAMEDTUPLE_KWARGS
+)
 
 
 class Sequence(Obj):
@@ -5277,6 +5560,12 @@ class Sequence(Obj):
     defaulted values existence validation by setting
     ``"allow_default_values": True`` :ref:`context <ctx>` option.
 
+    .. warning::
+
+       Check for default value existence is not performed in
+       ``evgen_mode``, because previously decoded values are not stored
+       in memory, to be able to compare them.
+
     Two sequences are equal if they have equal specification (schema),
     implicit/explicit tagging and the same values.
     """
@@ -5341,9 +5630,8 @@ class Sequence(Obj):
     def __getstate__(self):
         return SequenceState(
             __version__,
-            self.specs,
-            {k: copy(v) for k, v in iteritems(self._value)},
             self.tag,
+            self._tag_order,
             self._expl,
             self.default,
             self.optional,
@@ -5353,22 +5641,14 @@ class Sequence(Obj):
             self.expl_lenindef,
             self.lenindef,
             self.ber_encoded,
+            self.specs,
+            {k: copy(v) for k, v in iteritems(self._value)},
         )
 
     def __setstate__(self, state):
         super(Sequence, self).__setstate__(state)
         self.specs = state.specs
         self._value = state.value
-        self.tag = state.tag
-        self._expl = state.expl
-        self.default = state.default
-        self.optional = state.optional
-        self.offset = state.offset
-        self.llen = state.llen
-        self.vlen = state.vlen
-        self.expl_lenindef = state.expl_lenindef
-        self.lenindef = state.lenindef
-        self.ber_encoded = state.ber_encoded
 
     def __eq__(self, their):
         if not isinstance(their, self.__class__):
@@ -5439,7 +5719,13 @@ class Sequence(Obj):
         v = b"".join(v.encode() for v in self._values_for_encoding())
         return b"".join((self.tag, len_encode(len(v)), v))
 
-    def _decode(self, tlv, offset, decode_path, ctx, tag_only):
+    def _encode_cer(self, writer):
+        write_full(writer, self.tag + LENINDEF)
+        for v in self._values_for_encoding():
+            v.encode_cer(writer)
+        write_full(writer, EOC)
+
+    def _decode(self, tlv, offset, decode_path, ctx, tag_only, evgen_mode):
         try:
             t, tlen, lv = tag_strip(tlv)
         except DecodeError as err:
@@ -5456,7 +5742,8 @@ class Sequence(Obj):
                 offset=offset,
             )
         if tag_only:  # pragma: no cover
-            return None
+            yield None
+            return
         lenindef = False
         ctx_bered = ctx.get("bered", False)
         try:
@@ -5500,21 +5787,33 @@ class Sequence(Obj):
                 continue
             sub_decode_path = decode_path + (name,)
             try:
-                value, v_tail = spec.decode(
-                    v,
-                    sub_offset,
-                    leavemm=True,
-                    decode_path=sub_decode_path,
-                    ctx=ctx,
-                    _ctx_immutable=False,
-                )
+                if evgen_mode:
+                    for _decode_path, value, v_tail in spec.decode_evgen(
+                            v,
+                            sub_offset,
+                            leavemm=True,
+                            decode_path=sub_decode_path,
+                            ctx=ctx,
+                            _ctx_immutable=False,
+                    ):
+                        yield _decode_path, value, v_tail
+                else:
+                    _, value, v_tail = next(spec.decode_evgen(
+                        v,
+                        sub_offset,
+                        leavemm=True,
+                        decode_path=sub_decode_path,
+                        ctx=ctx,
+                        _ctx_immutable=False,
+                        _evgen_mode=False,
+                    ))
             except TagMismatch as err:
                 if (len(err.decode_path) == len(decode_path) + 1) and spec.optional:
                     continue
                 raise
 
             defined = get_def_by_path(ctx.get("_defines", ()), sub_decode_path)
-            if defined is not None:
+            if not evgen_mode and defined is not None:
                 defined_by, defined_spec = defined
                 if issubclass(value.__class__, SequenceOf):
                     for i, _value in enumerate(value):
@@ -5566,31 +5865,32 @@ class Sequence(Obj):
             vlen += value_len
             sub_offset += value_len
             v = v_tail
-            if spec.default is not None and value == spec.default:
-                if ctx_bered or ctx_allow_default_values:
-                    ber_encoded = True
-                else:
-                    raise DecodeError(
-                        "DEFAULT value met",
-                        klass=self.__class__,
-                        decode_path=sub_decode_path,
-                        offset=sub_offset,
-                    )
-            values[name] = value
-
-            spec_defines = getattr(spec, "defines", ())
-            if len(spec_defines) == 0:
-                defines_by_path = ctx.get("defines_by_path", ())
-                if len(defines_by_path) > 0:
-                    spec_defines = get_def_by_path(defines_by_path, sub_decode_path)
-            if spec_defines is not None and len(spec_defines) > 0:
-                for rel_path, schema in spec_defines:
-                    defined = schema.get(value, None)
-                    if defined is not None:
-                        ctx.setdefault("_defines", []).append((
-                            abs_decode_path(sub_decode_path[:-1], rel_path),
-                            (value, defined),
-                        ))
+            if not evgen_mode:
+                if spec.default is not None and value == spec.default:
+                    # This will not work in evgen_mode
+                    if ctx_bered or ctx_allow_default_values:
+                        ber_encoded = True
+                    else:
+                        raise DecodeError(
+                            "DEFAULT value met",
+                            klass=self.__class__,
+                            decode_path=sub_decode_path,
+                            offset=sub_offset,
+                        )
+                values[name] = value
+                spec_defines = getattr(spec, "defines", ())
+                if len(spec_defines) == 0:
+                    defines_by_path = ctx.get("defines_by_path", ())
+                    if len(defines_by_path) > 0:
+                        spec_defines = get_def_by_path(defines_by_path, sub_decode_path)
+                if spec_defines is not None and len(spec_defines) > 0:
+                    for rel_path, schema in spec_defines:
+                        defined = schema.get(value, None)
+                        if defined is not None:
+                            ctx.setdefault("_defines", []).append((
+                                abs_decode_path(sub_decode_path[:-1], rel_path),
+                                (value, defined),
+                            ))
         if lenindef:
             if v[:EOC_LEN].tobytes() != EOC:
                 raise DecodeError(
@@ -5619,7 +5919,7 @@ class Sequence(Obj):
         obj._value = values
         obj.lenindef = lenindef
         obj.ber_encoded = ber_encoded
-        return obj, tail
+        yield decode_path, obj, tail
 
     def __repr__(self):
         value = pp_console_row(next(self.pps()))
@@ -5681,15 +5981,22 @@ class Set(Sequence):
     asn1_type_name = "SET"
 
     def _encode(self):
-        raws = [v.encode() for v in self._values_for_encoding()]
-        raws.sort()
-        v = b"".join(raws)
+        v = b"".join(value.encode() for value in sorted(
+            self._values_for_encoding(),
+            key=attrgetter("tag_order"),
+        ))
         return b"".join((self.tag, len_encode(len(v)), v))
 
-    def _specs_items(self):
-        return iteritems(self.specs)
+    def _encode_cer(self, writer):
+        write_full(writer, self.tag + LENINDEF)
+        for v in sorted(
+                self._values_for_encoding(),
+                key=attrgetter("tag_order_cer"),
+        ):
+            v.encode_cer(writer)
+        write_full(writer, EOC)
 
-    def _decode(self, tlv, offset, decode_path, ctx, tag_only):
+    def _decode(self, tlv, offset, decode_path, ctx, tag_only, evgen_mode):
         try:
             t, tlen, lv = tag_strip(tlv)
         except DecodeError as err:
@@ -5706,7 +6013,8 @@ class Set(Sequence):
                 offset=offset,
             )
         if tag_only:
-            return None
+            yield None
+            return
         lenindef = False
         ctx_bered = ctx.get("bered", False)
         try:
@@ -5742,12 +6050,13 @@ class Set(Sequence):
         ber_encoded = False
         ctx_allow_default_values = ctx.get("allow_default_values", False)
         ctx_allow_unordered_set = ctx.get("allow_unordered_set", False)
-        value_prev = memoryview(v[:0])
+        tag_order_prev = (0, 0)
+        _specs_items = copy(self.specs)
 
         while len(v) > 0:
             if lenindef and v[:EOC_LEN].tobytes() == EOC:
                 break
-            for name, spec in self._specs_items():
+            for name, spec in iteritems(_specs_items):
                 sub_decode_path = decode_path + (name,)
                 try:
                     spec.decode(
@@ -5768,16 +6077,29 @@ class Set(Sequence):
                     decode_path=decode_path,
                     offset=offset,
                 )
-            value, v_tail = spec.decode(
-                v,
-                sub_offset,
-                leavemm=True,
-                decode_path=sub_decode_path,
-                ctx=ctx,
-                _ctx_immutable=False,
-            )
+            if evgen_mode:
+                for _decode_path, value, v_tail in spec.decode_evgen(
+                        v,
+                        sub_offset,
+                        leavemm=True,
+                        decode_path=sub_decode_path,
+                        ctx=ctx,
+                        _ctx_immutable=False,
+                ):
+                    yield _decode_path, value, v_tail
+            else:
+                _, value, v_tail = next(spec.decode_evgen(
+                    v,
+                    sub_offset,
+                    leavemm=True,
+                    decode_path=sub_decode_path,
+                    ctx=ctx,
+                    _ctx_immutable=False,
+                    _evgen_mode=False,
+                ))
+            value_tag_order = value.tag_order
             value_len = value.fulllen
-            if value_prev.tobytes() > v[:value_len].tobytes():
+            if tag_order_prev >= value_tag_order:
                 if ctx_bered or ctx_allow_unordered_set:
                     ber_encoded = True
                 else:
@@ -5799,10 +6121,12 @@ class Set(Sequence):
                     offset=sub_offset,
                 )
             values[name] = value
-            value_prev = v[:value_len]
+            del _specs_items[name]
+            tag_order_prev = value_tag_order
             sub_offset += value_len
             vlen += value_len
             v = v_tail
+
         obj = self.__class__(
             schema=self.specs,
             impl=self.tag,
@@ -5821,7 +6145,6 @@ class Set(Sequence):
                 )
             tail = v[EOC_LEN:]
             obj.lenindef = True
-        obj._value = values
         for name, spec in iteritems(self.specs):
             if name not in values and not spec.optional:
                 raise DecodeError(
@@ -5830,27 +6153,17 @@ class Set(Sequence):
                     decode_path=decode_path,
                     offset=offset,
                 )
+        if not evgen_mode:
+            obj._value = values
         obj.ber_encoded = ber_encoded
-        return obj, tail
+        yield decode_path, obj, tail
 
 
-SequenceOfState = namedtuple("SequenceOfState", (
-    "version",
-    "spec",
-    "value",
-    "bound_min",
-    "bound_max",
-    "tag",
-    "expl",
-    "default",
-    "optional",
-    "offset",
-    "llen",
-    "vlen",
-    "expl_lenindef",
-    "lenindef",
-    "ber_encoded",
-), **NAMEDTUPLE_KWARGS)
+SequenceOfState = namedtuple(
+    "SequenceOfState",
+    BasicState._fields + ("spec", "value", "bound_min", "bound_max"),
+    **NAMEDTUPLE_KWARGS
+)
 
 
 class SequenceOf(Obj):
@@ -5951,11 +6264,8 @@ class SequenceOf(Obj):
     def __getstate__(self):
         return SequenceOfState(
             __version__,
-            self.spec,
-            [copy(v) for v in self._value],
-            self._bound_min,
-            self._bound_max,
             self.tag,
+            self._tag_order,
             self._expl,
             self.default,
             self.optional,
@@ -5965,6 +6275,10 @@ class SequenceOf(Obj):
             self.expl_lenindef,
             self.lenindef,
             self.ber_encoded,
+            self.spec,
+            [copy(v) for v in self._value],
+            self._bound_min,
+            self._bound_max,
         )
 
     def __setstate__(self, state):
@@ -5973,16 +6287,6 @@ class SequenceOf(Obj):
         self._value = state.value
         self._bound_min = state.bound_min
         self._bound_max = state.bound_max
-        self.tag = state.tag
-        self._expl = state.expl
-        self.default = state.default
-        self.optional = state.optional
-        self.offset = state.offset
-        self.llen = state.llen
-        self.vlen = state.vlen
-        self.expl_lenindef = state.expl_lenindef
-        self.lenindef = state.lenindef
-        self.ber_encoded = state.ber_encoded
 
     def __eq__(self, their):
         if isinstance(their, self.__class__):
@@ -6055,7 +6359,22 @@ class SequenceOf(Obj):
         v = b"".join(v.encode() for v in self._values_for_encoding())
         return b"".join((self.tag, len_encode(len(v)), v))
 
-    def _decode(self, tlv, offset, decode_path, ctx, tag_only, ordering_check=False):
+    def _encode_cer(self, writer):
+        write_full(writer, self.tag + LENINDEF)
+        for v in self._values_for_encoding():
+            v.encode_cer(writer)
+        write_full(writer, EOC)
+
+    def _decode(
+            self,
+            tlv,
+            offset,
+            decode_path,
+            ctx,
+            tag_only,
+            evgen_mode,
+            ordering_check=False,
+    ):
         try:
             t, tlen, lv = tag_strip(tlv)
         except DecodeError as err:
@@ -6072,7 +6391,8 @@ class SequenceOf(Obj):
                 offset=offset,
             )
         if tag_only:
-            return None
+            yield None
+            return
         lenindef = False
         ctx_bered = ctx.get("bered", False)
         try:
@@ -6106,6 +6426,7 @@ class SequenceOf(Obj):
         vlen = 0
         sub_offset = offset + tlen + llen
         _value = []
+        _value_count = 0
         ctx_allow_unordered_set = ctx.get("allow_unordered_set", False)
         value_prev = memoryview(v[:0])
         ber_encoded = False
@@ -6113,15 +6434,27 @@ class SequenceOf(Obj):
         while len(v) > 0:
             if lenindef and v[:EOC_LEN].tobytes() == EOC:
                 break
-            sub_decode_path = decode_path + (str(len(_value)),)
-            value, v_tail = spec.decode(
-                v,
-                sub_offset,
-                leavemm=True,
-                decode_path=sub_decode_path,
-                ctx=ctx,
-                _ctx_immutable=False,
-            )
+            sub_decode_path = decode_path + (str(_value_count),)
+            if evgen_mode:
+                for _decode_path, value, v_tail in spec.decode_evgen(
+                        v,
+                        sub_offset,
+                        leavemm=True,
+                        decode_path=sub_decode_path,
+                        ctx=ctx,
+                        _ctx_immutable=False,
+                ):
+                    yield _decode_path, value, v_tail
+            else:
+                _, value, v_tail = next(spec.decode_evgen(
+                    v,
+                    sub_offset,
+                    leavemm=True,
+                    decode_path=sub_decode_path,
+                    ctx=ctx,
+                    _ctx_immutable=False,
+                    _evgen_mode=False,
+                ))
             value_len = value.fulllen
             if ordering_check:
                 if value_prev.tobytes() > v[:value_len].tobytes():
@@ -6135,13 +6468,22 @@ class SequenceOf(Obj):
                             offset=sub_offset,
                         )
                 value_prev = v[:value_len]
-            _value.append(value)
+            _value_count += 1
+            if not evgen_mode:
+                _value.append(value)
             sub_offset += value_len
             vlen += value_len
             v = v_tail
+        if evgen_mode and not self._bound_min <= _value_count <= self._bound_max:
+            raise DecodeError(
+                msg=str(BoundsError(self._bound_min, _value_count, self._bound_max)),
+                klass=self.__class__,
+                decode_path=decode_path,
+                offset=offset,
+            )
         try:
             obj = self.__class__(
-                value=_value,
+                value=None if evgen_mode else _value,
                 schema=spec,
                 bounds=(self._bound_min, self._bound_max),
                 impl=self.tag,
@@ -6168,7 +6510,7 @@ class SequenceOf(Obj):
             obj.lenindef = True
             tail = v[EOC_LEN:]
         obj.ber_encoded = ber_encoded
-        return obj, tail
+        yield decode_path, obj, tail
 
     def __repr__(self):
         return "%s[%s]" % (
@@ -6215,18 +6557,23 @@ class SetOf(SequenceOf):
     asn1_type_name = "SET OF"
 
     def _encode(self):
-        raws = [v.encode() for v in self._values_for_encoding()]
-        raws.sort()
-        v = b"".join(raws)
+        v = b"".join(sorted(v.encode() for v in self._values_for_encoding()))
         return b"".join((self.tag, len_encode(len(v)), v))
 
-    def _decode(self, tlv, offset, decode_path, ctx, tag_only):
+    def _encode_cer(self, writer):
+        write_full(writer, self.tag + LENINDEF)
+        for v in sorted(encode_cer(v) for v in self._values_for_encoding()):
+            write_full(writer, v)
+        write_full(writer, EOC)
+
+    def _decode(self, tlv, offset, decode_path, ctx, tag_only, evgen_mode):
         return super(SetOf, self)._decode(
             tlv,
             offset,
             decode_path,
             ctx,
             tag_only,
+            evgen_mode,
             ordering_check=True,
         )