From 98f13762d7e18c0ba12044eed56e9198ca056c66 Mon Sep 17 00:00:00 2001
From: Erik Romijn <eromijn@solidlinks.nl>
Date: Sat, 22 Feb 2014 16:00:23 +0100
Subject: [PATCH] Fixed #22123 -- EmailValidator now also accepts IPv6 literals
 in addresses

---
 django/core/validators.py | 28 +++++++++++++++++++++-------
 docs/releases/1.7.txt     |  3 +++
 tests/validators/tests.py |  7 +++++++
 3 files changed, 31 insertions(+), 7 deletions(-)

diff --git a/django/core/validators.py b/django/core/validators.py
index 6bbee8e7d2a..83e1a12a2fd 100644
--- a/django/core/validators.py
+++ b/django/core/validators.py
@@ -109,9 +109,11 @@ class EmailValidator(object):
         r'|^"([\001-\010\013\014\016-\037!#-\[\]-\177]|\\[\001-\011\013\014\016-\177])*"$)',  # quoted-string
         re.IGNORECASE)
     domain_regex = re.compile(
-        r'(?:[A-Z0-9](?:[A-Z0-9-]{0,61}[A-Z0-9])?\.)+(?:[A-Z]{2,6}|[A-Z0-9-]{2,})$'  # domain
-        # literal form, ipv4 address (SMTP 4.1.3)
-        r'|^\[(25[0-5]|2[0-4]\d|[0-1]?\d?\d)(\.(25[0-5]|2[0-4]\d|[0-1]?\d?\d)){3}\]$',
+        r'(?:[A-Z0-9](?:[A-Z0-9-]{0,61}[A-Z0-9])?\.)+(?:[A-Z]{2,6}|[A-Z0-9-]{2,})$',
+        re.IGNORECASE)
+    literal_regex = re.compile(
+        # literal form, ipv4 or ipv6 address (SMTP 4.1.3)
+        r'\[([A-f0-9:\.]+)\]$',
         re.IGNORECASE)
     domain_whitelist = ['localhost']
 
@@ -135,18 +137,30 @@ class EmailValidator(object):
             raise ValidationError(self.message, code=self.code)
 
         if (not domain_part in self.domain_whitelist and
-                not self.domain_regex.match(domain_part)):
+                not self.validate_domain_part(domain_part)):
             # Try for possible IDN domain-part
             try:
                 domain_part = domain_part.encode('idna').decode('ascii')
-                if not self.domain_regex.match(domain_part):
-                    raise ValidationError(self.message, code=self.code)
-                else:
+                if self.validate_domain_part(domain_part):
                     return
             except UnicodeError:
                 pass
             raise ValidationError(self.message, code=self.code)
 
+    def validate_domain_part(self, domain_part):
+        if self.domain_regex.match(domain_part):
+            return True
+
+        literal_match = self.literal_regex.match(domain_part)
+        if literal_match:
+            ip_address = literal_match.group(1)
+            try:
+                validate_ipv46_address(ip_address)
+                return True
+            except ValidationError:
+                pass
+        return False
+
     def __eq__(self, other):
         return isinstance(other, EmailValidator) and (self.domain_whitelist == other.domain_whitelist) and (self.message == other.message) and (self.code == other.code)
 
diff --git a/docs/releases/1.7.txt b/docs/releases/1.7.txt
index e3144f3d292..400c5d07597 100644
--- a/docs/releases/1.7.txt
+++ b/docs/releases/1.7.txt
@@ -760,6 +760,9 @@ Validators
   ``schemes`` argument which allows customization of the accepted URI schemes
   (instead of the defaults ``http(s)`` and ``ftp(s)``).
 
+* :func:`~django.core.validators.validate_email` now accepts addresses with
+  IPv6 literals, like ``example@[2001:db8::1]``, as specified in RFC 5321.
+
 Backwards incompatible changes in 1.7
 =====================================
 
diff --git a/tests/validators/tests.py b/tests/validators/tests.py
index 54e5dfbeed2..b88d71fa68c 100644
--- a/tests/validators/tests.py
+++ b/tests/validators/tests.py
@@ -33,6 +33,9 @@ TEST_DATA = (
     (validate_email, 'email@here.com', None),
     (validate_email, 'weirder-email@here.and.there.com', None),
     (validate_email, 'email@[127.0.0.1]', None),
+    (validate_email, 'email@[2001:dB8::1]', None),
+    (validate_email, 'email@[2001:dB8:0:0:0:0:0:1]', None),
+    (validate_email, 'email@[::fffF:127.0.0.1]', None),
     (validate_email, 'example@valid-----hyphens.com', None),
     (validate_email, 'example@valid-with-hyphens.com', None),
     (validate_email, 'test@domain.with.idn.tld.उदाहरण.परीक्षा', None),
@@ -49,6 +52,10 @@ TEST_DATA = (
     (validate_email, 'abc@.com', ValidationError),
     (validate_email, 'something@@somewhere.com', ValidationError),
     (validate_email, 'email@127.0.0.1', ValidationError),
+    (validate_email, 'email@[127.0.0.256]', ValidationError),
+    (validate_email, 'email@[2001:db8::12345]', ValidationError),
+    (validate_email, 'email@[2001:db8:0:0:0:0:1]', ValidationError),
+    (validate_email, 'email@[::ffff:127.0.0.256]', ValidationError),
     (validate_email, 'example@invalid-.com', ValidationError),
     (validate_email, 'example@-invalid.com', ValidationError),
     (validate_email, 'example@inv-.alid-.com', ValidationError),