ObjectIdentifier codec fixed to work properly with arc 0 and arc 2 values

5 files changed, 55 insertions, 13 deletions

diff --git a/CHANGES b/CHANGES
index 43374eb..414efc5 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,6 +1,7 @@
 Revision 0.1.8
 --------------
 
+- ObjectIdentifier codec fixed to work properly with arc 0 and arc 2 values.
 - Unicode initializer support added to OctetString type and derivatives.
 - Fix to SEQUENCE and SET types to give them their private componentTypes
   collection (which is a NamedTypes object) so that they won't collide in
diff --git a/pyasn1/codec/ber/decoder.py b/pyasn1/codec/ber/decoder.py
index 2c6896f..1530a54 100644
--- a/pyasn1/codec/ber/decoder.py
+++ b/pyasn1/codec/ber/decoder.py
@@ -216,14 +216,24 @@ class ObjectIdentifierDecoder(AbstractSimpleDecoder):
         if not head:
             raise error.PyAsn1Error('Empty substrate')
 
-        # Get the first subid
+        # Decode the first octet
+        index = 1
         subId = oct2int(head[0])
-        oid = divmod(subId, 40)
+        if 0 <= subId <= 39:
+            oid = 0, subId
+        elif 40 <= subId <= 79:
+            oid = 1, subId - 40
+        elif subId >= 80:
+            oid = 2,
+            index = 0
+        else:
+            raise error.PyAsn1Error('Malformed first OID octet: %s' % subId)
 
-        index = 1
         substrateLen = len(head)
         while index < substrateLen:
             subId = oct2int(head[index])
+            if index == 0:
+                subId -= 80
             index = index + 1
             if subId == 128:
                 # ASN.1 spec forbids leading zeros (0x80) in sub-ID OID
diff --git a/pyasn1/codec/ber/encoder.py b/pyasn1/codec/ber/encoder.py
index cfb59a8..c4db49e 100644
--- a/pyasn1/codec/ber/encoder.py
+++ b/pyasn1/codec/ber/encoder.py
@@ -166,13 +166,20 @@ class ObjectIdentifierEncoder(AbstractItemEncoder):
             if len(oid) < 2:
                 raise error.PyAsn1Error('Short OID %s' % (value,))
 
+            index = 2
+
             # Build the first twos
-            if oid[0] > 6 or oid[1] > 39 or oid[0] == 6 and oid[1] > 15:
+            if oid[0] == 0 and 0 <= oid[1] <= 39:
+                octets = (oid[1],)
+            elif oid[0] == 1 and 0 <= oid[1] <= 39:
+                octets = (oid[1] + 40,)
+            elif oid[0] == 2:
+                octets = ()
+                index = 1
+            else:
                 raise error.PyAsn1Error(
                     'Initial sub-ID overflow %s in OID %s' % (oid[:2], value)
                     )
-            octets = (oid[0] * 40 + oid[1],)
-            index = 2
 
         # Cycle through subids
         for subid in oid[index:]:
@@ -192,7 +199,10 @@ class ObjectIdentifierEncoder(AbstractItemEncoder):
                     subid = subid >> 7 
                 # Add packed Sub-Object ID to resulted Object ID
                 octets += res
-                
+
+        if index == 1:
+            octets = (octets[0]+80,) + octets[1:]
+
         return ints2octs(octets), 0
 
 class RealEncoder(AbstractItemEncoder):
diff --git a/test/codec/ber/test_decoder.py b/test/codec/ber/test_decoder.py
index b581bc6..294e0ce 100644
--- a/test/codec/ber/test_decoder.py
+++ b/test/codec/ber/test_decoder.py
@@ -187,13 +187,19 @@ class ObjectIdentifierDecoderTestCase(unittest.TestCase):
 
     def testEdges1(self):
         assert decoder.decode(
-            ints2octs((6, 1, 255))
-            ) == ((6,15), null)
+            ints2octs((6, 1, 39))
+            ) == ((0,39), null)
 
     def testEdges2(self):
         assert decoder.decode(
-            ints2octs((6, 1, 239))
-            ) == ((5,39), null)
+            ints2octs((6, 1, 79))
+            ) == ((1,39), null)
+
+    def testEdges3(self):
+        assert decoder.decode(
+            ints2octs((6, 5, 223, 255, 255, 255, 127))
+            ) == ((2,0xffffffff), null)
+
 
     def testEdges3(self):
         assert decoder.decode(
diff --git a/test/codec/ber/test_encoder.py b/test/codec/ber/test_encoder.py
index edf43b0..3a0a1b2 100644
--- a/test/codec/ber/test_encoder.py
+++ b/test/codec/ber/test_encoder.py
@@ -132,10 +132,25 @@ class NullEncoderTestCase(unittest.TestCase):
         assert encoder.encode(univ.Null('')) == ints2octs((5, 0))
 
 class ObjectIdentifierEncoderTestCase(unittest.TestCase):
-    def testNull(self):
+    def testOne(self):
         assert encoder.encode(
             univ.ObjectIdentifier((1,3,6,0,0xffffe))
-            ) == ints2octs((6, 6, 43, 6, 0, 191, 255, 126))
+        ) == ints2octs((6, 6, 43, 6, 0, 191, 255, 126))
+
+    def testEdge1(self):
+        assert encoder.encode(
+            univ.ObjectIdentifier((0,39))
+        ) == ints2octs((6,1,39))
+
+    def testEdge2(self):
+        assert encoder.encode(
+            univ.ObjectIdentifier((1,39))
+        ) == ints2octs((6,1,79))
+
+    def testEdge3(self):
+        assert encoder.encode(
+            univ.ObjectIdentifier((2,0xffffffff))
+        ) == ints2octs((6, 5, 223, 255, 255, 255, 127))
 
 class RealEncoderTestCase(unittest.TestCase):
     def testChar(self):