diff --git a/pasn1.py b/pasn1.py
index 1f71e77..7015f40 100644
--- a/pasn1.py
+++ b/pasn1.py
@@ -15,6 +15,8 @@ import pdb
 import sys
 import unittest
 
+__all__ = [ 'dumps', 'loads', 'ASN1Coder' ]
+
 def _numtostr(n):
 	hs = '%x' % n
 	if len(hs) & 1 == 1:
@@ -165,9 +167,14 @@ class ASN1Coder(object):
 
 	def dec_dict(self, d, pos, end):
 		r = {}
+		vend = pos
 		while pos < end:
 			k, kend = self._loads(d, pos, end)
+			#if kend > end:
+			#	raise ValueError('key past end')
 			v, vend = self._loads(d, kend, end)
+			if vend > end:
+				raise ValueError('value past end')
 
 			r[k] = v
 			pos = vend
@@ -188,8 +195,11 @@ class ASN1Coder(object):
 
 	def dec_list(self, d, pos, end):
 		r = []
+		vend = pos
 		while pos < end:
 			v, vend = self._loads(d, pos, end)
+			if vend > end:
+				raise ValueError('load past end')
 			r.append(v)
 			pos = vend
 
@@ -262,15 +272,21 @@ class ASN1Coder(object):
 			return float('nan'), end
 		elif v == 0b01000011:
 			return float('-0'), end
+		elif v & 0b110000:
+			raise ValueError('base must be 2')
+		elif v & 0b1100:
+			raise ValueError('scaling factor must be 0')
+		elif v & 0b11000000 == 0:
+			raise ValueError('decimal encoding not supported')
 		#elif v & 0b11000000 == 0b01000000:
 		#	raise ValueError('invalid encoding')
 
-		if not (v & 0b10000000):
-			raise NotImplementedError
-
 		if v & 3 == 3:
 			pexp = pos + 2
-			eexp = pos + 2 + ord(d[pos + 1])
+			explen = ord(d[pos + 1])
+			if explen <= 3:
+				raise ValueError('must use other length encoding')
+			eexp = pos + 2 + explen
 		else:
 			pexp = pos + 1
 			eexp = pos + 1 + (v & 3) + 1
@@ -311,6 +327,62 @@ class ASN1Coder(object):
 			raise ValueError('entire string not consumed')
 		return r
 
+def deeptypecmp(obj, o):
+	#print 'dtc:', `obj`, `o`
+	if type(obj) != type(o):
+		return False
+	if type(obj) in (str, unicode):
+		return True
+
+	if type(obj) in (list, set):
+		for i, j in zip(obj, o):
+			if not deeptypecmp(i, j):
+				return False
+
+	if type(obj) in (dict,):
+		itms = obj.items()
+		itms.sort()
+		nitms = o.items()
+		nitms.sort()
+		for (k, v), (nk, nv) in zip(itms, nitms):
+			if not deeptypecmp(k, nk):
+				return False
+			if not deeptypecmp(v, nv):
+				return False
+			
+	return True
+
+class Test_deeptypecmp(unittest.TestCase):
+	def test_true(self):
+		for i in ((1,1), ('sldkfj', 'sldkfj')
+		    ):
+			self.assertTrue(deeptypecmp(*i))
+
+	def test_false(self):
+		for i in (([[]], [{}]), ([1], ['str']), ([], set()),
+		    ({1: 2, 5: u'sdlkfj'}, {1: 2, 5: 'sdlkfj'}),
+		    ({1: 2, u'sdlkfj': 5}, {1: 2, 'sdlkfj': 5}),
+		    ):
+			self.assertFalse(deeptypecmp(*i))
+
+def genfailures(obj):
+	s = dumps(obj)
+	for i in xrange(len(s)):
+		for j in (chr(x) for x in xrange(256)):
+			ts = s[:i] + j + s[i + 1:]
+			if ts == s:
+				continue
+			try:
+				o = loads(ts, consume=True)
+				if o != obj or not deeptypecmp(o, obj):
+					raise ValueError
+			except (ValueError, KeyError, IndexError):
+				pass
+			except Exception:
+				raise
+			else:
+				raise AssertionError('uncaught modification: %s, byte %d, orig: %02x' % (ts.encode('hex'), i, ord(s[i])))
+
 _coder = ASN1Coder()
 dumps = _coder.dumps
 loads = _coder.loads
@@ -332,6 +404,12 @@ class TestCode(unittest.TestCase):
 
 		self.assertEqual(dumps(.15625), '090380fb05'.decode('hex'))
 
+	def test_fuzzing(self):
+		genfailures(float(1))
+		genfailures([ 1, 2, 'sdlkfj' ])
+		genfailures({ 1: 2, 5: 'sdlkfj' })
+		genfailures(set([ 1, 2, 'sdlkfj' ]))
+
 	def test_consume(self):
 		b = dumps(5)
 		self.assertRaises(ValueError, loads, b + '398473', consume=True)
@@ -349,7 +427,16 @@ class TestCode(unittest.TestCase):
 
 	def test_invalids(self):
 		# Add tests for base 8, 16 floats among others
-		for v in [ '010101', ]:
+		for v in [ '010101',
+		    '0903040001',	# float scaling factor
+		    '0903840001',	# float scaling factor
+		    '0903100001',	# float base
+		    '0903900001',	# float base
+		    '0903000001',	# float decimal encoding
+		    '0903830001',	# float exponent encoding
+		    '3007020101020102040673646c6b666a',	# list short string still valid
+		    'c007020101020102020105040673646c6b666a', # dict short value still valid
+		    ]:
 			self.assertRaises(ValueError, loads, v.decode('hex'))
 
 	def test_cryptoutilasn1(self):
@@ -377,7 +464,9 @@ class TestCode(unittest.TestCase):
 		    float('.15625'),
 		    'weoifjwef',
 		    u'\U0001f4a9',
-		    set((1,2,3)), set((1,'sjlfdkj', None, float('inf'))),
+		    [],
+		    {},
+		    set(), set((1,2,3)), set((1,'sjlfdkj', None, float('inf'))),
 		    ]:
 			s = dumps(i)
 			o = loads(s)