diff --git a/simplekv/crypt.py b/simplekv/crypt.py
index 3a2a9cc4..60df6208 100644
--- a/simplekv/crypt.py
+++ b/simplekv/crypt.py
@@ -21,8 +21,8 @@ def __init__(self, hm, source):
                                         '(too small)')
 
     def read(self, n=None):
-        if '' == self.buffer or 0 == n:
-            return ''
+        if b'' == self.buffer or 0 == n:
+            return b''
 
         new_read = self.source.read(n) if n is not None else self.source.read()
         finished = (n is None or len(new_read) != n)
@@ -94,11 +94,6 @@ def __init__(self, secret_key, decorated_store, hashfunc=hashlib.sha256):
         self.__hashfunc = hashfunc
         self.__secret_key = bytes(secret_key)
 
-    @property
-    def hmac_digestsize(self):
-        # returns, in bytes, the size of the digest
-        return self.hmac_mixin_hashfunc().digestsize
-
     def __new_hmac(self, key, msg=None):
         if not msg:
             msg = b''
@@ -130,7 +125,7 @@ def get_file(self, key, file):
         if isinstance(file, str):
             try:
                 f = open(file, 'wb')
-            except OSError as e:
+            except (OSError, IOError) as e:
                 raise IOError('Error opening %s for writing: %r' % (
                     file, e
                 ))
diff --git a/tests/test_hmac.py b/tests/test_hmac.py
index 9ace6c19..a26fa922 100644
--- a/tests/test_hmac.py
+++ b/tests/test_hmac.py
@@ -39,10 +39,27 @@ def create_reader(self, stored_blob, secret_key, hashfunc):
     def chunk_sizes(self, value):
         return [10 ** n for n in xrange(2, 8)]
 
+    def test_close(self, create_reader):
+        reader = create_reader()
+        assert not reader.source.closed
+        reader.close()
+        assert reader.source.closed
+
+    def test_close_via_context(self, create_reader):
+        reader = create_reader()
+        assert not reader.source.closed
+        with reader as r:
+            assert r is reader
+        assert reader.source.closed
+
     def test_reading_limit_0(self, create_reader):
         reader = create_reader()
-        assert reader.read(0) == ''
-        assert reader.read(0) == ''
+        data = reader.read(0)
+        assert isinstance(data, bytes)
+        assert len(data) == 0
+        data = reader.read(0)
+        assert isinstance(data, bytes)
+        assert len(data) == 0
 
     def test_reading_with_limit(self, secret_key, hashfunc, value,
                                 create_reader, chunk_sizes):
@@ -100,6 +117,7 @@ def test_unbounded_read(self, value, create_reader):
 # this only works with dicts, as we access the internal structures to
 # manipulate values
 class HMACDec(object):
+
     @pytest.fixture
     def hmacstore(self, secret_key, store):
         return HMACDecorator(secret_key, store)
@@ -111,6 +129,32 @@ def test_get_fails_on_manipulation(self, hmacstore, key, value):
         with pytest.raises(VerificationException):
             hmacstore.get(key)
 
+    def test_copy_raises_not_implemented(self, store):
+        with pytest.raises(NotImplementedError):
+            HMACDecorator(b'secret', store).copy(u'src', u'dest')
+
+    def test_put_file_obj(self, key, value, hmacstore):
+        hmacstore.put_file(key, BytesIO(value))
+        assert hmacstore.get(key) == value
+
+    def test_put_file_str(self, key, value, hmacstore):
+        with tempfile.NamedTemporaryFile(mode='wb', delete=False) as f:
+            f.write(value)
+        hmacstore.put_file(key, f.name)
+        assert hmacstore.get(key) == value
+
+    def test_get_file_obj(self, key, value, hmacstore):
+        hmacstore.put(key, value)
+        b = BytesIO()
+        hmacstore.get_file(key, b)
+        assert b.getvalue() == value
+
+    def test_get_file_non_writable_target(self, key, value, hmacstore):
+        hmacstore.put(key, value)
+        path = '/tmp/this/file/does/not/exist'
+        with pytest.raises(IOError, match='Error opening {} for writing'.format(path)):
+            hmacstore.get_file(key, path)
+
     def test_get_file_fails_on_manipulation(self, hmacstore, key, value):
         hmacstore.put(key, value)
         hmacstore.d[key] += b('a')