From 916d61bdffb1f0df435c8f3bffab4150d03de12b Mon Sep 17 00:00:00 2001
From: William Grant <me@williamgrant.id.au>
Date: Thu, 17 Mar 2011 22:39:45 +1100
Subject: [PATCH] Add EMSA-PKCS1-v1_5-ENCODE tests. One fails because we don't
 require at least 8 bytes of padding.

---
 dkim/tests/__init__.py    |  2 ++
 dkim/tests/test_crypto.py | 60 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 62 insertions(+)
 create mode 100644 dkim/tests/test_crypto.py

diff --git a/dkim/tests/__init__.py b/dkim/tests/__init__.py
index 7fb38ab..4c258fc 100644
--- a/dkim/tests/__init__.py
+++ b/dkim/tests/__init__.py
@@ -21,10 +21,12 @@ import unittest
 
 def test_suite():
     from dkim.tests import (
+        test_crypto,
         test_dkim,
         test_util,
         )
     modules = [
+        test_crypto,
         test_dkim,
         test_util,
         ]
diff --git a/dkim/tests/test_crypto.py b/dkim/tests/test_crypto.py
new file mode 100644
index 0000000..f882e92
--- /dev/null
+++ b/dkim/tests/test_crypto.py
@@ -0,0 +1,60 @@
+# This software is provided 'as-is', without any express or implied
+# warranty.  In no event will the author be held liable for any damages
+# arising from the use of this software.
+#
+# Permission is granted to anyone to use this software for any purpose,
+# including commercial applications, and to alter it and redistribute it
+# freely, subject to the following restrictions:
+#
+# 1. The origin of this software must not be misrepresented; you must not
+#    claim that you wrote the original software. If you use this software
+#    in a product, an acknowledgment in the product documentation would be
+#    appreciated but is not required.
+# 2. Altered source versions must be plainly marked as such, and must not be
+#    misrepresented as being the original software.
+# 3. This notice may not be removed or altered from any source distribution.
+#
+# Copyright (c) 2011 William Grant <me@williamgrant.id.au>
+
+import unittest
+
+from dkim import (
+    HASHID_SHA1,
+    HASHID_SHA256,
+    )
+from dkim.crypto import (
+    DigestTooLargeError,
+    EMSA_PKCS1_v1_5_encode,
+    )
+
+
+class TestEMSA_PKCS1_v1_5(unittest.TestCase):
+
+    def test_encode_sha256(self):
+        digest = '0123456789abcdef0123456789abcdef'
+        self.assertEquals(
+            '\x00\x01\xff\xff\xff\xff\xff\xff\xff\xff\x00'
+            '010\x0d\x06\x09\x60\x86\x48\x01\x65\x03\x04\x02\x01\x05\x00\x04 '
+            + digest,
+            EMSA_PKCS1_v1_5_encode(digest, 62, HASHID_SHA256))
+
+    def test_encode_sha1(self):
+        digest = '0123456789abcdef0123'
+        self.assertEquals(
+            '\x00\x01\xff\xff\xff\xff\xff\xff\xff\xff\x00'
+            '0!0\x09\x06\x05\x2b\x0e\x03\x02\x1a\x05\x00\x04\x14'
+            + digest,
+            EMSA_PKCS1_v1_5_encode(digest, 46, HASHID_SHA1))
+
+    def test_encode_forbids_too_short(self):
+        # PKCS#1 requires at least 8 bytes of padding, so there must be
+        # at least that much space.
+        digest = '0123456789abcdef0123'
+        self.assertRaises(
+            DigestTooLargeError,
+            EMSA_PKCS1_v1_5_encode, digest, 45, HASHID_SHA1)
+
+
+def test_suite():
+    from unittest import TestLoader
+    return TestLoader().loadTestsFromName(__name__)