at decoder, do not unconditionally cast substrate into bytes/str

3 files changed, 37 insertions, 6 deletions

diff --git a/CHANGES.rst b/CHANGES.rst
index 18072d0..e866cb8 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -3,6 +3,8 @@ Revision 0.3.3, released XX-08-2017
 -----------------------------------
 
 - Improved ASN.1 types instantiation performance
+- Improved BER/CER/DER decoder performance by not unconditionally casting
+  substrate into str/bytes.
 - Fixed SetOf ordering at CER/DER encoder
 - Fixed crash on conditional binascii module import
 - Fix to TagSet hash value build
diff --git a/pyasn1/codec/ber/decoder.py b/pyasn1/codec/ber/decoder.py
index 2766fe0..b7ff2e1 100644
--- a/pyasn1/codec/ber/decoder.py
+++ b/pyasn1/codec/ber/decoder.py
@@ -6,7 +6,7 @@
 #
 from pyasn1.type import base, tag, univ, char, useful, tagmap
 from pyasn1.codec.ber import eoo
-from pyasn1.compat.octets import oct2int, octs2ints, ints2octs, ensureString, null
+from pyasn1.compat.octets import oct2int, octs2ints, ints2octs, null
 from pyasn1.compat.integer import from_bytes
 from pyasn1 import debug, error
 
@@ -783,9 +783,16 @@ for typeDecoder in tagMap.values():
         typeMap[typeId] = typeDecoder
 
 
-(stDecodeTag, stDecodeLength, stGetValueDecoder, stGetValueDecoderByAsn1Spec,
- stGetValueDecoderByTag, stTryAsExplicitTag, stDecodeValue,
- stDumpRawValue, stErrorCondition, stStop) = [x for x in range(10)]
+(stDecodeTag,
+ stDecodeLength,
+ stGetValueDecoder,
+ stGetValueDecoderByAsn1Spec,
+ stGetValueDecoderByTag,
+ stTryAsExplicitTag,
+ stDecodeValue,
+ stDumpRawValue,
+ stErrorCondition,
+ stStop) = [x for x in range(10)]
 
 
 class Decoder(object):
@@ -814,8 +821,6 @@ class Decoder(object):
         if logger:
             logger('decoder called at scope %s with state %d, working with up to %d octets of substrate: %s' % (debug.scope, state, len(substrate), debug.hexdump(substrate)))
 
-        substrate = ensureString(substrate)
-
         # Look for end-of-octets sentinel
         if allowEoo and self.supportIndefLength:
             if substrate[:2] == self.__eooSentinel:
diff --git a/tests/codec/ber/test_decoder.py b/tests/codec/ber/test_decoder.py
index 03bfcab..0a53bcf 100644
--- a/tests/codec/ber/test_decoder.py
+++ b/tests/codec/ber/test_decoder.py
@@ -840,6 +840,30 @@ class EndOfOctetsTestCase(unittest.TestCase):
             assert 0, 'end-of-contents octets accepted with unexpected data'
 
 
+class NonStringDecoderTestCase(unittest.TestCase):
+    def setUp(self):
+        self.s = univ.Sequence(
+            componentType=namedtype.NamedTypes(
+                namedtype.NamedType('place-holder', univ.Null(null)),
+                namedtype.NamedType('first-name', univ.OctetString(null)),
+                namedtype.NamedType('age', univ.Integer(33))
+            )
+        )
+        self.s.setComponentByPosition(0, univ.Null(null))
+        self.s.setComponentByPosition(1, univ.OctetString('quick brown'))
+        self.s.setComponentByPosition(2, univ.Integer(1))
+
+        self.substrate = ints2octs([48, 18, 5, 0, 4, 11, 113, 117, 105, 99, 107, 32, 98, 114, 111, 119, 110, 2, 1, 1])
+
+    def testOctetString(self):
+        s, _ = decoder.decode(univ.OctetString(self.substrate), asn1Spec=self.s)
+        assert self.s == s
+
+    def testAny(self):
+        s, _ = decoder.decode(univ.Any(self.substrate), asn1Spec=self.s)
+        assert self.s == s
+
+
 suite = unittest.TestLoader().loadTestsFromModule(sys.modules[__name__])
 
 if __name__ == '__main__':