dkim files

LICENSE

@@ -17,7 +17,3 @@ freely, subject to the following restrictions:
 Copyright (c) 2008 Greg Hewgill http://hewgill.com
 See individual files for information about modification to these files and
 additional copyright information.
-
-Copyright (c) 2025 Uea-angkun Khunpradith https://dailitation.xyz
-See individual files for information about modification to these files and
-additional copyright information.

README.md

@@ -1,3 +1,9 @@
+dkimpy-smtputf8 – an RFC 8616-compliant fork of dkimpy.
+
+This fork adds support for internationalized email address (U-labels)
+
+# Original README
+
 dkimpy - DKIM (DomainKeys Identified Mail)
 https://launchpad.net/dkimpy/
 

dkim/__init__.py

@@ -30,6 +30,9 @@
 # Copyright (c) 2017 Valimail Inc
 # Contact: Gene Shuman <gene@valimail.com>
 #
+# This has been modified from the original software.
+# Copyright (c) 2025 dailitation.xyz
+# Contact: Uea-angkun Khunpradith <diskette@dailitation.xyz>
 
 
 import base64

dkim/tests/__init__.py

@@ -36,6 +36,7 @@ def test_suite():
         test_arc,
         test_dnsplug,
         test_dkim_generate,
+        test_dkim_utf8,
         )
     modules = [
         test_canonicalization,
@@ -48,6 +49,7 @@ def test_suite():
         test_arc,
         test_dnsplug,
         test_dkim_generate,
+        test_dkim_utf8,
         ]
     suites = [x.test_suite() for x in modules]
     return unittest.TestSuite(suites)

dkim/tests/test_dkim_utf8.py

@@ -0,0 +1,298 @@
+# 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>
+# Copyright (c) 2018 Scott Kitterman <scott@kitterman.com>
+
+import email
+import os.path
+import unittest
+import time
+
+import dkim
+
+
+def read_test_data(filename):
+    """Get the content of the given test data file.
+
+    The files live in dkim/tests/data.
+    """
+    path = os.path.join(os.path.dirname(__file__), 'data', filename)
+    with open(path, 'rb') as f:
+        return f.read()
+
+
+class TestFold(unittest.TestCase):
+
+    def test_short_line(self):
+        self.assertEqual(
+            b"foo", dkim.fold(b"foo"))
+
+    def test_long_line(self):
+        # The function is terribly broken, not passing even this simple
+        # test.
+        self.assertEqual(
+            b"foo" * 24 + b"\r\n foo", dkim.fold(b"foo" * 25))
+
+
+class TestSignAndVerify(unittest.TestCase):
+    """End-to-end signature and verification tests."""
+
+    def setUp(self):
+        self.message = read_test_data("ed25519test.msg")
+        self.message2 = read_test_data("ed25519test2.msg")
+        self.message3 = read_test_data("rfc6376.msg")
+        self.message4 = read_test_data("rfc6376.signed.msg")
+        self.key = read_test_data("ed25519test.key")
+        self.rfckey = read_test_data("rfc8032_7_1.key")
+
+    def dnsfunc(self, domain, timeout=5):
+        sample_dns = """\
+k=ed25519; \
+p=yi50DjK5O9pqbFpNHklsv9lqaS0ArSYu02qp1S0DW1Y="""
+
+        _dns_responses = {
+          'example._domainkey.canonical.com.': sample_dns,
+          'test._domainkey.example.net.': """v=DKIM1; k=ed25519; \
+p=yi50DjK5O9pqbFpNHklsv9lqaS0ArSYu02qp1S0DW1Y=""",
+          'sed._domainkey.test.ex.': read_test_data("eximtest.dns"),
+          'brisbane._domainkey.football.example.com.': """v=DKIM1; k=ed25519; \
+p=11qYAYKxCrfVS/7TyWQHOg7hcvPapiMlrwIaaPcHURo="""
+        }
+        try:
+            domain = domain.decode('ascii')
+        except UnicodeDecodeError:
+            return None
+        self.assertTrue(domain in _dns_responses,domain)
+        return _dns_responses[domain]
+
+    def test_verifies(self):
+        # A message verifies after being signed.
+        for header_algo in (b"simple", b"relaxed"):
+            for body_algo in (b"simple", b"relaxed"):
+                sig = dkim.sign(
+                    self.message, b"test", b"example.net", self.key,
+                    canonicalize=(header_algo, body_algo), signature_algorithm=b'ed25519-sha256')
+                res = dkim.verify(sig + self.message, dnsfunc=self.dnsfunc)
+                self.assertTrue(res)
+
+    def test_rfc8032_verifies(self):
+        # A message using RFC 8032 sample keys verifies after being signed.
+        for header_algo in (b"simple", b"relaxed"):
+            for body_algo in (b"simple", b"relaxed"):
+                sig = dkim.sign(
+                    self.message3, b"brisbane", b"football.example.com", self.rfckey,
+                    canonicalize=(header_algo, body_algo), signature_algorithm=b'ed25519-sha256')
+                res = dkim.verify(sig + self.message3, dnsfunc=self.dnsfunc)
+                self.assertTrue(res)
+
+    def test_rfc8032_previous_verifies(self):
+        # A message previously signed using RFC 8032 sample keys verifies after being signed.
+        for header_algo in (b"simple", b"relaxed"):
+            for body_algo in (b"simple", b"relaxed"):
+                sig = dkim.sign(
+                    self.message3, b"brisbane", b"football.example.com", self.rfckey,
+                    canonicalize=(header_algo, body_algo), signature_algorithm=b'ed25519-sha256')
+                d = dkim.DKIM(self.message4)
+                res = d.verify(dnsfunc=self.dnsfunc)
+                self.assertTrue(res)
+
+    def test_simple_signature(self):
+        # A message verifies after being signed with SHOULD headers
+        for header_algo in (b"simple", b"relaxed"):
+             for body_algo in (b"simple", b"relaxed"):
+                sig = dkim.sign(
+                    self.message, b"test", b"example.net", self.key,
+                    canonicalize=(header_algo, body_algo),
+                    include_headers=(b'from',) + dkim.DKIM.SHOULD,
+                    signature_algorithm=b'ed25519-sha256')
+                res = dkim.verify(sig + self.message, dnsfunc=self.dnsfunc)
+                self.assertTrue(res)
+
+    def test_verify_third_party(self):
+        # Message signed by prototype Exim implementation
+        res = dkim.verify(self.message2, dnsfunc=self.dnsfunc)
+        self.assertTrue(res)
+
+    def test_add_body_length(self):
+        sig = dkim.sign(
+            self.message, b"test", b"example.net", self.key, length=True,
+                signature_algorithm=b'ed25519-sha256')
+        msg = email.message_from_string(self.message.decode('utf-8'))
+        self.assertIn('; l=%s' % len(msg.get_payload() + '\n'), sig.decode('utf-8'))
+        res = dkim.verify(sig + self.message, dnsfunc=self.dnsfunc)
+        self.assertTrue(res)
+
+    def test_altered_body_fails(self):
+        # An altered body fails verification.
+        for header_algo in (b"simple", b"relaxed"):
+            for body_algo in (b"simple", b"relaxed"):
+                sig = dkim.sign(
+                    self.message, b"test", b"example.net", self.key,
+                    signature_algorithm=b'ed25519-sha256')
+                res = dkim.verify(
+                    sig + self.message + b"foo", dnsfunc=self.dnsfunc)
+                self.assertFalse(res)
+
+    def test_badly_encoded_domain_fails(self):
+        # Domains should be ASCII. Bad ASCII causes verification to fail.
+        sig = dkim.sign(self.message, b"test", b"example.net\xe9", self.key,
+            signature_algorithm=b'ed25519-sha256')
+        res = dkim.verify(sig + self.message, dnsfunc=self.dnsfunc)
+        self.assertFalse(res)
+
+    def test_dkim_signature_canonicalization(self):
+      # <https://bugs.launchpad.net/ubuntu/+source/pydkim/+bug/587783>
+      # Relaxed-mode header signing is wrong
+      # <https://bugs.launchpad.net/dkimpy/+bug/939128>
+      # Simple-mode signature header verification is wrong
+      # (should ignore FWS anywhere in signature tag: b=)
+      sample_msg = b"""\
+From: mbp@canonical.com
+To: scottk@example.net
+Subject: this is my
+    test message
+""".replace(b'\n', b'\r\n')
+
+      sample_privkey = b"""\
+fL+5V9EquCZAovKik3pA6Lk9zwCzoEtjIuIqK9ZXHHA=\
+"""
+
+      sample_pubkey = """\
+yi50DjK5O9pqbFpNHklsv9lqaS0ArSYu02qp1S0DW1Y=\
+"""
+
+      for header_mode in [dkim.Relaxed, dkim.Simple]:
+
+        dkim_header = dkim.sign(sample_msg, b'example', b'canonical.com',
+            sample_privkey, canonicalize=(header_mode, dkim.Relaxed),
+            signature_algorithm=b'ed25519-sha256')
+        # Folding dkim_header affects b= tag only, since dkim.sign folds
+        # sig_value with empty b= before hashing, and then appends the
+        # signature.  So folding dkim_header again adds FWS to
+        # the b= tag only.  This should be ignored even with
+        # simple canonicalization.
+        # http://tools.ietf.org/html/rfc4871#section-3.5
+        signed = dkim.fold(dkim_header) + sample_msg
+        result = dkim.verify(signed,dnsfunc=self.dnsfunc)
+        self.assertTrue(result)
+        dkim_header = dkim.fold(dkim_header)
+        # use a tab for last fold to test tab in FWS bug
+        pos = dkim_header.rindex(b'\r\n ')
+        dkim_header = dkim_header[:pos]+b'\r\n\t'+dkim_header[pos+3:]
+        result = dkim.verify(dkim_header + sample_msg,
+                dnsfunc=self.dnsfunc)
+        self.assertTrue(result)
+
+    def test_extra_headers(self):
+        # <https://bugs.launchpad.net/dkimpy/+bug/737311>
+        # extra headers above From caused failure
+        #message = read_test_data("test_extra.message")
+        message = read_test_data("message.mbox")
+        for header_algo in (b"simple", b"relaxed"):
+            for body_algo in (b"simple", b"relaxed"):
+                d = dkim.DKIM(message)
+                # bug requires a repeated header to manifest
+                d.should_not_sign.remove(b'received')
+                sig = d.sign(b"test", b"example.net", self.key,
+                    signature_algorithm=b'ed25519-sha256',
+                    include_headers=d.all_sign_headers(),
+                    canonicalize=(header_algo, body_algo))
+                dv = dkim.DKIM(sig + message)
+                res = dv.verify(dnsfunc=self.dnsfunc)
+                self.assertEqual(d.include_headers,dv.include_headers)
+                s = dkim.select_headers(d.headers,d.include_headers)
+                sv = dkim.select_headers(dv.headers,dv.include_headers)
+                self.assertEqual(s,sv)
+                self.assertTrue(res)
+
+    def test_multiple_from_fails(self):
+        # <https://bugs.launchpad.net/dkimpy/+bug/644046>
+        # additional From header fields should cause verify failure
+        hfrom = b'From: "Resident Evil" <sales@spammer.com>\r\n'
+        h,b = self.message.split(b'\n\n',1)
+        for header_algo in (b"simple", b"relaxed"):
+            for body_algo in (b"simple", b"relaxed"):
+                sig = dkim.sign(
+                    self.message, b"test", b"example.net", self.key,
+                    signature_algorithm=b'ed25519-sha256')
+                # adding an unknown header still verifies
+                h1 = h+b'\r\n'+b'X-Foo: bar'
+                message = b'\n\n'.join((h1,b))
+                res = dkim.verify(sig+message, dnsfunc=self.dnsfunc)
+                self.assertTrue(res)
+                # adding extra from at end should not verify
+                h1 = h+b'\r\n'+hfrom.strip()
+                message = b'\n\n'.join((h1,b))
+                res = dkim.verify(sig+message, dnsfunc=self.dnsfunc)
+                self.assertFalse(res)
+                # add extra from in front should not verify either
+                h1 = hfrom+h
+                message = b'\n\n'.join((h1,b))
+                res = dkim.verify(sig+message, dnsfunc=self.dnsfunc)
+                self.assertFalse(res)
+
+    def test_no_from_fails(self):
+        # Body From is mandatory to be in the message and mandatory to sign
+        sigerror = False
+        sig = ''
+        message = read_test_data('test_nofrom.message')
+        selector = 'test'
+        domain = 'example.net'
+        identity = None
+        try:
+            sig = dkim.sign(message, selector, domain,
+                read_test_data('ed25519test.key'), identity = identity,
+                signature_algorithm=b'ed25519-sha256')
+        except dkim.ParameterError as x:
+            sigerror = True
+        self.assertTrue(sigerror)
+
+    def test_validate_signature_fields(self):
+      sig = {b'v': b'1',
+      b'a': b'ed25519-sha256',
+      b'b': b'K/UUOt8lCtgjp3kSTogqBm9lY1Yax/NwZ+bKm39/WKzo5KYe3L/6RoIA/0oiDX4kO\n \t Qut49HCV6ZUe6dY9V5qWBwLanRs1sCnObaOGMpFfs8tU4TWpDSVXaNZAqn15XVW0WH\n \t EzOzUfVuatpa1kF4voIgSbmZHR1vN3WpRtcTBe/I=',
+      b'bh': b'n0HUwGCP28PkesXBPH82Kboy8LhNFWU9zUISIpAez7M=',
+      b'c': b'simple/simple',
+      b'd': b'kitterman.com',
+      b'i': b'scott@Kitterman.com',
+      b'h': b'From:To:Subject:Date:Cc:MIME-Version:Content-Type:\n \t Content-Transfer-Encoding:Message-Id',
+      b's': b'2007-00',
+      b't': b'1299525798'}
+      dkim.validate_signature_fields(sig)
+      # try new version
+      sigVer = sig.copy()
+      sigVer[b'v'] = 2
+      self.assertRaises(dkim.ValidationError, dkim.validate_signature_fields, sigVer)
+      # try with x
+      sigX = sig.copy()
+      sigX[b'x'] = b'1399525798'
+      dkim.validate_signature_fields(sig)
+      # try with late t
+      sigX[b't'] = b'1400000000'
+      self.assertRaises(dkim.ValidationError, dkim.validate_signature_fields, sigX)
+      # try without t
+      now = int(time.time())
+      sigX[b'x'] = str(now+400000).encode('ascii')
+      dkim.validate_signature_fields(sigX)
+      # try when expired a day ago
+      sigX[b'x'] = str(now - 24*3600).encode('ascii')
+      self.assertRaises(dkim.ValidationError, dkim.validate_signature_fields, sigX)
+
+
+def test_suite():
+    from unittest import TestLoader
+    return TestLoader().loadTestsFromName(__name__)

dkim/tests/test_dkimutf8.py

@@ -1,557 +0,0 @@
-# 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 email
-import os.path
-import unittest
-import time
-
-import dkim
-
-
-def read_test_data(filename):
-    """Get the content of the given test data file.
-
-    The files live in dkim/tests/data.
-    """
-    path = os.path.join(os.path.dirname(__file__), 'data', filename)
-    with open(path, 'rb') as f:
-        return f.read()
-
-
-class TestFold(unittest.TestCase):
-
-    def test_short_line(self):
-        self.assertEqual(
-            b"foo", dkim.fold(b"foo"))
-
-    def test_long_line(self):
-        # The function is terribly broken, not passing even this simple
-        # test.
-        self.assertEqual(
-            b"foo" * 24 + b"\r\n foo", dkim.fold(b"foo" * 25))
-
-    def test_linesep(self):
-        self.assertEqual(
-            b"foo" * 24 + b"\n foo", dkim.fold(b"foo" * 25, linesep=b"\n"))
-
-
-
-class TestSignAndVerify(unittest.TestCase):
-    """End-to-end signature and verification tests."""
-
-    def setUp(self):
-        self.message = read_test_data("test.message")
-        self.message3 = read_test_data("rfc6376.msg")
-        self.message4 = read_test_data("rfc6376.signed.msg")
-        self.message5 = read_test_data("rfc6376.signed.rsa.msg")
-        self.message6 = read_test_data("test.message.baddomain")
-        self.message7 = read_test_data("rfc6376.w1258.msg")
-        self.message8 = read_test_data("rfc6376.signed.no_t.msg")
-        self.key = read_test_data("test.private")
-        self.rfckey = read_test_data("rfc8032_7_1.key")
-
-    def dnsfunc(self, domain, timeout=5):
-        sample_dns = """\
-k=rsa; s=email;\
-p=MFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBANmBe10IgY+u7h3enWTukkqtUD5PR52T\
-b/mPfjC0QJTocVBq6Za/PlzfV+Py92VaCak19F4WrbVTK5Gg5tW220MCAwEAAQ=="""
-
-        _dns_responses = {
-          'example._domainkey.canonical.com.': sample_dns,
-          'test._domainkey.example.com.': read_test_data("test.txt"),
-          '20120113._domainkey.gmail.com.': """k=rsa; \
-p=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA1Kd87/UeJjenpabgbFwh\
-+eBCsSTrqmwIYYvywlbhbqoo2DymndFkbjOVIPIldNs/m40KF+yzMn1skyoxcTUGCQ\
-s8g3FgD2Ap3ZB5DekAo5wMmk4wimDO+U8QzI3SD07y2+07wlNWwIt8svnxgdxGkVbb\
-hzY8i+RQ9DpSVpPbF7ykQxtKXkv/ahW3KjViiAH+ghvvIhkx4xYSIc9oSwVmAl5Oct\
-MEeWUwg8Istjqz8BZeTWbf41fbNhte7Y+YqZOwq1Sd0DbvYAD9NOZK9vlfuac0598H\
-Y+vtSBczUiKERHv1yRbcaQtZFh5wtiRrN04BLUTD21MycBX5jYchHjPY/wIDAQAB"""
-        }
-        try:
-            domain = domain.decode('ascii')
-        except UnicodeDecodeError:
-            return None
-        self.assertTrue(domain in _dns_responses,domain)
-        return _dns_responses[domain]
-
-    def dnsfunc2(self, domain, timeout=5):
-        sample_dns = """\
-k=rsa; \
-p=MFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBANmBe10IgY+u7h3enWTukkqtUD5PR52T\
-b/mPfjC0QJTocVBq6Za/PlzfV+Py92VaCak19F4WrbVTK5Gg5tW220MCAwEAAQ=="""
-
-        _dns_responses = {
-          'example._domainkey.canonical.com.': sample_dns,
-          'test._domainkey.example.com.': read_test_data("test2.txt"),
-          '20120113._domainkey.gmail.com.': """\
-p=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA1Kd87/UeJjenpabgbFwh\
-+eBCsSTrqmwIYYvywlbhbqoo2DymndFkbjOVIPIldNs/m40KF+yzMn1skyoxcTUGCQ\
-s8g3FgD2Ap3ZB5DekAo5wMmk4wimDO+U8QzI3SD07y2+07wlNWwIt8svnxgdxGkVbb\
-hzY8i+RQ9DpSVpPbF7ykQxtKXkv/ahW3KjViiAH+ghvvIhkx4xYSIc9oSwVmAl5Oct\
-MEeWUwg8Istjqz8BZeTWbf41fbNhte7Y+YqZOwq1Sd0DbvYAD9NOZK9vlfuac0598H\
-Y+vtSBczUiKERHv1yRbcaQtZFh5wtiRrN04BLUTD21MycBX5jYchHjPY/wIDAQAB"""
-        }
-        try:
-            domain = domain.decode('ascii')
-        except UnicodeDecodeError:
-            return None
-        self.assertTrue(domain in _dns_responses,domain)
-        return _dns_responses[domain]
-
-    def dnsfunc3(self, domain, timeout=5):
-        sample_dns = """\
-k=rsa; \
-p=MFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBANmBe10IgY+u7h3enWTukkqtUD5PR52T\
-b/mPfjC0QJTocVBq6Za/PlzfV+Py92VaCak19F4WrbVTK5Gg5tW220MCAwEAAQ=="""
-
-        _dns_responses = {
-          'example._domainkey.canonical.com.': sample_dns,
-          'test._domainkey.example.com.': read_test_data("badversion.txt"),
-          '20120113._domainkey.gmail.com.': """\
-p=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA1Kd87/UeJjenpabgbFwh\
-+eBCsSTrqmwIYYvywlbhbqoo2DymndFkbjOVIPIldNs/m40KF+yzMn1skyoxcTUGCQ\
-s8g3FgD2Ap3ZB5DekAo5wMmk4wimDO+U8QzI3SD07y2+07wlNWwIt8svnxgdxGkVbb\
-hzY8i+RQ9DpSVpPbF7ykQxtKXkv/ahW3KjViiAH+ghvvIhkx4xYSIc9oSwVmAl5Oct\
-MEeWUwg8Istjqz8BZeTWbf41fbNhte7Y+YqZOwq1Sd0DbvYAD9NOZK9vlfuac0598H\
-Y+vtSBczUiKERHv1yRbcaQtZFh5wtiRrN04BLUTD21MycBX5jYchHjPY/wIDAQAB"""
-        }
-        try:
-            domain = domain.decode('ascii')
-        except UnicodeDecodeError:
-            return None
-        self.assertTrue(domain in _dns_responses,domain)
-        return _dns_responses[domain]
-
-    def dnsfunc4(self, domain, timeout=5):
-        sample_dns = """\
-k=rsa; \
-p=MFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBANmBe10IgY+u7h3enWTukkqtUD5PR52T\
-b/mPfjC0QJTocVBq6Za/PlzfV+Py92VaCak19F4WrbVTK5Gg5tW220MCAwEAAQ=="""
-
-        _dns_responses = {
-          'example._domainkey.canonical.com.': sample_dns,
-          'test._domainkey.example.com.': read_test_data("badk.txt"),
-          '20120113._domainkey.gmail.com.': """\
-p=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA1Kd87/UeJjenpabgbFwh\
-+eBCsSTrqmwIYYvywlbhbqoo2DymndFkbjOVIPIldNs/m40KF+yzMn1skyoxcTUGCQ\
-s8g3FgD2Ap3ZB5DekAo5wMmk4wimDO+U8QzI3SD07y2+07wlNWwIt8svnxgdxGkVbb\
-hzY8i+RQ9DpSVpPbF7ykQxtKXkv/ahW3KjViiAH+ghvvIhkx4xYSIc9oSwVmAl5Oct\
-MEeWUwg8Istjqz8BZeTWbf41fbNhte7Y+YqZOwq1Sd0DbvYAD9NOZK9vlfuac0598H\
-Y+vtSBczUiKERHv1yRbcaQtZFh5wtiRrN04BLUTD21MycBX5jYchHjPY/wIDAQAB"""
-        }
-        try:
-            domain = domain.decode('ascii')
-        except UnicodeDecodeError:
-            return None
-        self.assertTrue(domain in _dns_responses,domain)
-        return _dns_responses[domain]
-
-    def dnsfunc5(self, domain, timeout=5):
-        sample_dns = """\
-k=rsa; \
-p=MFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBANmBe10IgY+u7h3enWTukkqtUD5PR52T\
-b/mPfjC0QJTocVBq6Za/PlzfV+Py92VaCak19F4WrbVTK5Gg5tW220MCAwEAAQ=="""
-
-        _dns_responses = {
-          'example._domainkey.canonical.com.': sample_dns,
-          'test._domainkey.football.example.com.': read_test_data("test.txt"),
-          'brisbane._domainkey.football.example.com.': """v=DKIM1; k=ed25519; \
-p=11qYAYKxCrfVS/7TyWQHOg7hcvPapiMlrwIaaPcHURo="""
-        }
-        try:
-            domain = domain.decode('ascii')
-        except UnicodeDecodeError:
-            return None
-        self.assertTrue(domain in _dns_responses,domain)
-        return _dns_responses[domain]
-
-    def dnsfunc6(self, domain, timeout=5):
-        sample_dns = """\
-k=rsa; \
-p=MFwwDQYJKoZIhvNAQEBBQADSwAwSAJBANmBe10IgY+u7h3enWTukkqtUD5PR52T\
-b/mPfjC0QJTocVBq6Za/PlzfV+Py92VaCak19F4WrbVTK5Gg5tW220MCAwEAAQ=="""
-
-        _dns_responses = {
-          'test._domainkey.football.example.com.': sample_dns,
-          'brisbane._domainkey.football.example.com.': """v=DKIM1; k=ed25519; \
-p=11qYAYKxCrfVS/7TyWQHOg7hcvPapiMlrwIaaPcHURo="""
-        }
-        try:
-            domain = domain.decode('ascii')
-        except UnicodeDecodeError:
-            return None
-        self.assertTrue(domain in _dns_responses,domain)
-        return _dns_responses[domain]
-
-    def dnsfunc7(self, domain, timeout=5):
-        sample_dns = """\
-k=rsa; s=email;\
-p=MFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBANmBe10IgY+u7h3enWTukkqtUD5PR52T\
-b/mPfjC0QJTocVBq6Za/PlzfV+Py92VaCak19F4WrbVTK5Gg5tW220MCAwEAAQ=="""
-
-        _dns_responses = {
-          'test._domainkey.legitimate.com(.attacker.com.': read_test_data("test.txt"),
-        }
-        try:
-            domain = domain.decode('ascii')
-        except UnicodeDecodeError:
-            return None
-        self.assertTrue(domain in _dns_responses,domain)
-        return _dns_responses[domain]
-
-
-    def test_verifies(self):
-        # A message verifies after being signed.
-        for header_algo in (b"simple", b"relaxed"):
-            for body_algo in (b"simple", b"relaxed"):
-                sig = dkim.sign(
-                    self.message, b"test", b"example.com", self.key,
-                    canonicalize=(header_algo, body_algo))
-                res = dkim.verify(sig + self.message, dnsfunc=self.dnsfunc)
-                self.assertTrue(res)
-
-    def test_verifies_nosig(self):
-        # A message without signature does not verify.
-        res = dkim.verify(self.message, dnsfunc=self.dnsfunc)
-        self.assertFalse(res)
-
-    def test_double_verifies(self):
-        # A message also containing a ed25519 signature verifies after being signed with rsa.
-        for header_algo in (b"simple", b"relaxed"):
-            for body_algo in (b"simple", b"relaxed"):
-                sig = dkim.sign(
-                    self.message3, b"test", b"football.example.com", self.key,
-                    canonicalize=(header_algo, body_algo), signature_algorithm=b'rsa-sha256')
-                res = dkim.verify(sig + self.message3, dnsfunc=self.dnsfunc5)
-                self.assertTrue(res)
-
-    def test_double_previous_verifies(self):
-        # A message previously signed using both rsa and ed25519 verifies after being signed.
-        for header_algo in (b"simple", b"relaxed"):
-            for body_algo in (b"simple", b"relaxed"):
-                sig = dkim.sign(
-                    self.message3, b"test", b"football.example.com", self.key,
-                    canonicalize=(header_algo, body_algo), signature_algorithm=b'rsa-sha256')
-                d = dkim.DKIM(self.message4)
-                res = d.verify(dnsfunc=self.dnsfunc5)
-                self.assertTrue(res)
-
-    def test_non_utf8(self):
-        # A message with Windows-1258 encoding is signed and verifies.
-        for header_algo in (b"simple", b"relaxed"):
-            for body_algo in (b"simple", b"relaxed"):
-                sig = dkim.sign(
-                    self.message7, b"test", b"football.example.com", self.key,
-                    canonicalize=(header_algo, body_algo), signature_algorithm=b'rsa-sha256')
-                d = dkim.DKIM(self.message7)
-                res = d.verify(dnsfunc=self.dnsfunc5)
-                # As of 1.1.0 this won't verify, but at least we don't crash.  FIXME
-                self.assertFalse(res)
-
-    def test_no_t(self):
-        # Signature Timestamp is optional, so don't crash if it's missing.
-        d = dkim.DKIM(self.message8)
-        res = d.verify(dnsfunc=self.dnsfunc5)
-        # Signature won't verify, but that's not what we are testing.
-        self.assertFalse(res)
-
-    def test_catch_bad_key(self):
-        # Raise correct error for defective public key.
-        d = dkim.DKIM(self.message5)
-        res = d.verify(dnsfunc=self.dnsfunc6)
-        self.assertFalse(res)
-
-    def test_verifies_lflinesep(self):
-        # A message verifies after being signed.
-        for header_algo in (b"simple", b"relaxed"):
-            for body_algo in (b"simple", b"relaxed"):
-                sig = dkim.sign(
-                    self.message, b"test", b"example.com", self.key,
-                    canonicalize=(header_algo, body_algo), linesep=b"\n")
-                res = dkim.verify(sig + self.message, dnsfunc=self.dnsfunc)
-                self.assertFalse(b'\r\n' in sig)
-                self.assertTrue(res)
-
-    def test_implicit_k(self):
-        # A message verifies after being signed when k= tag is not provided.
-        for header_algo in (b"simple", b"relaxed"):
-            for body_algo in (b"simple", b"relaxed"):
-                sig = dkim.sign(
-                    self.message, b"test", b"example.com", self.key,
-                    canonicalize=(header_algo, body_algo))
-                res = dkim.verify(sig + self.message, dnsfunc=self.dnsfunc2)
-                self.assertTrue(res)
-
-    def test_bad_version(self):
-        # A error is detected if a bad version is used.
-        for header_algo in (b"simple", b"relaxed"):
-            for body_algo in (b"simple", b"relaxed"):
-                sig = dkim.sign(
-                    self.message, b"test", b"example.com", self.key,
-                    canonicalize=(header_algo, body_algo))
-                res = dkim.verify(sig + self.message, dnsfunc=self.dnsfunc3)
-                self.assertFalse(res)
-
-    def test_unknown_k(self):
-        # A error is detected if an unknown algorithm is in the k= tag.
-        for header_algo in (b"simple", b"relaxed"):
-            for body_algo in (b"simple", b"relaxed"):
-                sig = dkim.sign(
-                    self.message, b"test", b"example.com", self.key,
-                    canonicalize=(header_algo, body_algo))
-                res = dkim.verify(sig + self.message, dnsfunc=self.dnsfunc4)
-                self.assertFalse(res)
-
-    def test_invalid_domain_sign(self):
-        # RFC6376 says domain can be Alpha, Num, - only.
-        sig = dkim.sign(
-            self.message, b"test", b"legitimate.com(.attacker.com", self.key)
-        res = dkim.verify(sig + self.message, dnsfunc=self.dnsfunc7)
-        self.assertFalse(res)
-
-    def test_invalid_domain_verify(self):
-        # RFC6376 says domain can be Alpha, Num, - only.
-        res = dkim.verify(self.message6, dnsfunc=self.dnsfunc7)
-        self.assertFalse(res)
-
-    def test_simple_signature(self):
-        # A message verifies after being signed with SHOULD headers
-        for header_algo in (b"simple", b"relaxed"):
-             for body_algo in (b"simple", b"relaxed"):
-                sig = dkim.sign(
-                    self.message, b"test", b"example.com", self.key,
-                    canonicalize=(header_algo, body_algo),
-                    include_headers=(b'from',) + dkim.DKIM.SHOULD)
-                res = dkim.verify(sig + self.message, dnsfunc=self.dnsfunc)
-                self.assertTrue(res)
-
-    def test_string_include(self):
-        # A message can be signed when the include_headers is string
-        for header_algo in (b"simple", b"relaxed"):
-             for body_algo in (b"simple", b"relaxed"):
-                sig = dkim.sign(
-                    self.message, b"test", b"example.com", self.key,
-                    canonicalize=(header_algo, body_algo),
-                    include_headers=('from',) )
-                res = dkim.verify(sig + self.message, dnsfunc=self.dnsfunc)
-                self.assertTrue(res)
-
-    def test_add_body_length(self):
-        sig = dkim.sign(
-            self.message, b"test", b"example.com", self.key, length=True)
-        msg = email.message_from_string(self.message.decode('utf-8'))
-        self.assertIn('; l=%s' % len(msg.get_payload() + '\n'), sig.decode('utf-8'))
-        res = dkim.verify(sig + self.message, dnsfunc=self.dnsfunc)
-        self.assertTrue(res)
-
-    def test_altered_body_fails(self):
-        # An altered body fails verification.
-        for header_algo in (b"simple", b"relaxed"):
-            for body_algo in (b"simple", b"relaxed"):
-                sig = dkim.sign(
-                    self.message, b"test", b"example.com", self.key)
-                res = dkim.verify(
-                    sig + self.message + b"foo", dnsfunc=self.dnsfunc)
-                self.assertFalse(res)
-
-    def test_l_verify(self):
-        # Sign with l=, add text, should verify
-        for header_algo in (b"simple", b"relaxed"):
-            for body_algo in (b"simple", b"relaxed"):
-                sig = dkim.sign(
-                    self.message, b"test", b"example.com", self.key,
-                    canonicalize=(header_algo, body_algo), length=True)
-                self.message += b'added more text\n'
-                res = dkim.verify(sig + self.message, dnsfunc=self.dnsfunc)
-                self.assertTrue(res)
-
-    def test_present(self):
-        # Test DKIM.present().
-        d = dkim.DKIM(self.message,signature_algorithm=b'rsa-sha256')
-        present = d.present()
-        self.assertFalse(present)
-        sig = d.sign(b"test", b"example.com", self.key)
-        signed = sig + self.message
-        d2 = dkim.DKIM(signed)
-        present = d2.present()
-        self.assertTrue(present)
-
-    def test_badly_encoded_domain_fails(self):
-        # Domains should be ASCII. Bad ASCII causes verification to fail.
-        sig = dkim.sign(self.message, b"test", b"example.com\xe9", self.key)
-        res = dkim.verify(sig + self.message, dnsfunc=self.dnsfunc)
-        self.assertFalse(res)
-
-    def test_dkim_signature_canonicalization(self):
-      # <https://bugs.launchpad.net/ubuntu/+source/pydkim/+bug/587783>
-      # Relaxed-mode header signing is wrong
-      # <https://bugs.launchpad.net/dkimpy/+bug/939128>
-      # Simple-mode signature header verification is wrong
-      # (should ignore FWS anywhere in signature tag: b=)
-      sample_msg = b"""\
-From: mbp@canonical.com
-To: scottk@example.com
-Subject: this is my
-    test message
-""".replace(b'\n', b'\r\n')
-
-      sample_privkey = b"""\
------BEGIN RSA PRIVATE KEY-----
-MIIBOwIBAAJBANmBe10IgY+u7h3enWTukkqtUD5PR52Tb/mPfjC0QJTocVBq6Za/
-PlzfV+Py92VaCak19F4WrbVTK5Gg5tW220MCAwEAAQJAYFUKsD+uMlcFu1D3YNaR
-EGYGXjJ6w32jYGJ/P072M3yWOq2S1dvDthI3nRT8MFjZ1wHDAYHrSpfDNJ3v2fvZ
-cQIhAPgRPmVYn+TGd59asiqG1SZqh+p+CRYHW7B8BsicG5t3AiEA4HYNOohlgWan
-8tKgqLJgUdPFbaHZO1nDyBgvV8hvWZUCIQDDdCq6hYKuKeYUy8w3j7cgJq3ih922
-2qNWwdJCfCWQbwIgTY0cBvQnNe0067WQIpj2pG7pkHZR6qqZ9SE+AjNTHX0CIQCI
-Mgq55Y9MCq5wqzy141rnxrJxTwK9ABo3IAFMWEov3g==
------END RSA PRIVATE KEY-----
-"""
-
-      sample_pubkey = """\
------BEGIN PUBLIC KEY-----
-MFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBANmBe10IgY+u7h3enWTukkqtUD5PR52T
-b/mPfjC0QJTocVBq6Za/PlzfV+Py92VaCak19F4WrbVTK5Gg5tW220MCAwEAAQ==
------END PUBLIC KEY-----
-"""
-
-      for header_mode in [dkim.Relaxed, dkim.Simple]:
-
-        dkim_header = dkim.sign(sample_msg, b'example', b'canonical.com',
-            sample_privkey, canonicalize=(header_mode, dkim.Relaxed))
-        # Folding dkim_header affects b= tag only, since dkim.sign folds
-        # sig_value with empty b= before hashing, and then appends the
-        # signature.  So folding dkim_header again adds FWS to
-        # the b= tag only.  This should be ignored even with
-        # simple canonicalization.
-        # http://tools.ietf.org/html/rfc4871#section-3.5
-        signed = dkim.fold(dkim_header) + sample_msg
-        result = dkim.verify(signed,dnsfunc=self.dnsfunc,
-                minkey=512)
-        self.assertTrue(result)
-        dkim_header = dkim.fold(dkim_header)
-        # use a tab for last fold to test tab in FWS bug
-        pos = dkim_header.rindex(b'\r\n ')
-        dkim_header = dkim_header[:pos]+b'\r\n\t'+dkim_header[pos+3:]
-        result = dkim.verify(dkim_header + sample_msg,
-                dnsfunc=self.dnsfunc, minkey=512)
-        self.assertTrue(result)
-
-    def test_degenerate_folding(self):
-        # <http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=711751>
-        # degenerate folding is ugly but legal
-        message = read_test_data("test2.message")
-        dv = dkim.DKIM(message)
-        res = dv.verify(dnsfunc=self.dnsfunc)
-        self.assertTrue(res)
-
-    def test_extra_headers(self):
-        # <https://bugs.launchpad.net/dkimpy/+bug/737311>
-        # extra headers above From caused failure
-        #message = read_test_data("test_extra.message")
-        message = read_test_data("message.mbox")
-        for header_algo in (b"simple", b"relaxed"):
-            for body_algo in (b"simple", b"relaxed"):
-                d = dkim.DKIM(message)
-                # bug requires a repeated header to manifest
-                d.should_not_sign.remove(b'received')
-                sig = d.sign(b"test", b"example.com", self.key,
-                    include_headers=d.all_sign_headers(),
-                    canonicalize=(header_algo, body_algo))
-                dv = dkim.DKIM(sig + message)
-                res = dv.verify(dnsfunc=self.dnsfunc)
-                self.assertEqual(d.include_headers,dv.include_headers)
-                s = dkim.select_headers(d.headers,d.include_headers)
-                sv = dkim.select_headers(dv.headers,dv.include_headers)
-                self.assertEqual(s,sv)
-                self.assertTrue(res)
-
-    def test_multiple_from_fails(self):
-        # <https://bugs.launchpad.net/dkimpy/+bug/644046>
-        # additional From header fields should cause verify failure
-        hfrom = b'From: "Resident Evil" <sales@spammer.com>\r\n'
-        h,b = self.message.split(b'\n\n',1)
-        for header_algo in (b"simple", b"relaxed"):
-            for body_algo in (b"simple", b"relaxed"):
-                sig = dkim.sign(
-                    self.message, b"test", b"example.com", self.key)
-                # adding an unknown header still verifies
-                h1 = h+b'\r\n'+b'X-Foo: bar'
-                message = b'\n\n'.join((h1,b))
-                res = dkim.verify(sig+message, dnsfunc=self.dnsfunc)
-                self.assertTrue(res)
-                # adding extra from at end should not verify
-                h1 = h+b'\r\n'+hfrom.strip()
-                message = b'\n\n'.join((h1,b))
-                res = dkim.verify(sig+message, dnsfunc=self.dnsfunc)
-                self.assertFalse(res)
-                # add extra from in front should not verify either
-                h1 = hfrom+h
-                message = b'\n\n'.join((h1,b))
-                res = dkim.verify(sig+message, dnsfunc=self.dnsfunc)
-                self.assertFalse(res)
-
-    def test_no_from_fails(self):
-        # Body From is mandatory to be in the message and mandatory to sign
-        sigerror = False
-        sig = ''
-        message = read_test_data('test_nofrom.message')
-        selector = 'test'
-        domain = 'example.com'
-        identity = None
-        try:
-            sig = dkim.sign(message, selector, domain, read_test_data('test.private'), identity = identity)
-        except dkim.ParameterError as x:
-            sigerror = True
-        self.assertTrue(sigerror)
-
-    def test_validate_signature_fields(self):
-      sig = {b'v': b'1',
-      b'a': b'rsa-sha256',
-      b'b': b'K/UUOt8lCtgjp3kSTogqBm9lY1Yax/NwZ+bKm39/WKzo5KYe3L/6RoIA/0oiDX4kO\n \t Qut49HCV6ZUe6dY9V5qWBwLanRs1sCnObaOGMpFfs8tU4TWpDSVXaNZAqn15XVW0WH\n \t EzOzUfVuatpa1kF4voIgSbmZHR1vN3WpRtcTBe/I=',
-      b'bh': b'n0HUwGCP28PkesXBPH82Kboy8LhNFWU9zUISIpAez7M=',
-      b'c': b'simple/simple',
-      b'd': b'kitterman.com',
-      b'i': b'scott@Kitterman.com',
-      b'h': b'From:To:Subject:Date:Cc:MIME-Version:Content-Type:\n \t Content-Transfer-Encoding:Message-Id',
-      b's': b'2007-00',
-      b't': b'1299525798'}
-      dkim.validate_signature_fields(sig)
-      # try new version
-      sigVer = sig.copy()
-      sigVer[b'v'] = 2
-      self.assertRaises(dkim.ValidationError, dkim.validate_signature_fields, sigVer)
-      # try with x
-      sigX = sig.copy()
-      sigX[b'x'] = b'1399525798'
-      dkim.validate_signature_fields(sig)
-      # try with late t
-      sigX[b't'] = b'1400000000'
-      self.assertRaises(dkim.ValidationError, dkim.validate_signature_fields, sigX)
-      # try without t
-      now = int(time.time())
-      sigX[b'x'] = str(now+400000).encode('ascii')
-      dkim.validate_signature_fields(sigX)
-      # try when expired a day ago
-      sigX[b'x'] = str(now - 24*3600).encode('ascii')
-      self.assertRaises(dkim.ValidationError, dkim.validate_signature_fields, sigX)
-
-
-def test_suite():
-    from unittest import TestLoader
-    return TestLoader().loadTestsFromName(__name__)