From: Bob Halley <halley@dnspython.org>
Date: Sun, 6 Jan 2019 21:22:25 +0000 (-0800)
Subject: If there are no non-ASCII codepoints in the input, treat the name as
X-Git-Tag: v2.0.0rc1~377
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=dda972af4c15baf963e42c2869b1114a5cf5e31f;p=thirdparty%2Fdnspython.git

If there are no non-ASCII codepoints in the input, treat the name as
an ordinary domain name in from_text and do NOT apply any IDNA.

This makes non-Unicode binary names like
\150\151\152\153\154\155\156\157\158\159. work properly again.
[Issue #270]
---

diff --git a/dns/name.py b/dns/name.py
index cd465cd5..a9fc177b 100644
--- a/dns/name.py
+++ b/dns/name.py
@@ -111,12 +111,6 @@ class IDNACodec(object):
     def is_idna(self, label):
         return label.lower().startswith(b'xn--')
 
-    def is_all_ascii(self, label):
-        for c in label:
-            if ord(c) > 0x7f:
-                return False
-        return True
-
     def encode(self, label):
         raise NotImplementedError
 
@@ -204,7 +198,7 @@ class IDNA2008Codec(IDNACodec):
     def encode(self, label):
         if label == '':
             return b''
-        if self.allow_pure_ascii and self.is_all_ascii(label):
+        if self.allow_pure_ascii and is_all_ascii(label):
             return label.encode('ascii')
         if not have_idna_2008:
             raise NoIDNA2008
@@ -868,6 +862,11 @@ def from_unicode(text, origin=root, idna_codec=None):
         labels.extend(list(origin.labels))
     return Name(labels)
 
+def is_all_ascii(text):
+    for c in text:
+        if ord(c) > 0x7f:
+            return False
+    return True
 
 def from_text(text, origin=root, idna_codec=None):
     """Convert text into a Name object.
@@ -885,7 +884,18 @@ def from_text(text, origin=root, idna_codec=None):
     """
 
     if isinstance(text, str):
-        return from_unicode(text, origin, idna_codec)
+        if not is_all_ascii(text):
+            # Some codepoint in the input text is > 127, so IDNA applies.
+            return from_unicode(text, origin, idna_codec)
+        # The input is all ASCII, so treat this like an ordinary non-IDNA
+        # domain name.  Note that "all ASCII" is about the input text,
+        # not the codepoints in the domain name.  E.g. if text has value
+        #
+        # r'\150\151\152\153\154\155\156\157\158\159'
+        #
+        # then it's still "all ASCII" even though the domain name has
+        # codepoints > 127.
+        text = text.encode('ascii')
     if not isinstance(text, bytes):
         raise ValueError("input to from_text() must be a string")
     if not (origin is None or isinstance(origin, Name)):
diff --git a/tests/test_name.py b/tests/test_name.py
index 02a67c28..bea30a2d 100644
--- a/tests/test_name.py
+++ b/tests/test_name.py
@@ -260,6 +260,18 @@ class NameTestCase(unittest.TestCase):
         t = n.to_unicode()
         self.assertEqual(t, r'a\.b.c.')
 
+    def testToText13(self):
+        n = dns.name.from_text(r'\150\151\152\153\154\155\156\157\158\159.')
+        t = n.to_text()
+        self.assertEqual(t, r'\150\151\152\153\154\155\156\157\158\159.')
+
+    def testToText14(self):
+        # You can't send this to_unicode() as it wasn't unicode to begin with.
+        def bad():
+            n = dns.name.from_text(r'\150\151\152\153\154\155\156\157\158\159.')
+            t = n.to_unicode()
+        self.failUnlessRaises(UnicodeDecodeError, bad)
+
     def testSlice1(self):
         n = dns.name.from_text(r'a.b.c.', origin=None)
         s = n[:]