Handling the redirect modifier

[runelynge]

Thanks for this fine script - your work is highly appreciated!

If I read the code correctly the txt record is split into tokens which are then split into key value pairs using ":" as the separator. This construct seems mishandle the redirect modifier which uses the equality sign to set a value a la "redirect=". The code has a handler for a redirect key and will do recursive resolving if found, but I can't see how such a key would ever be identified.

I don't know what the right way to fix this is, but I've done an ugly workaround rewriting any token match of "redirect=" to "redirect:":

$ diff -u spf_dump.py.orig spf_dump.py
--- spf_dump.py.orig    Sat Feb  6 14:46:32 2016
+++ spf_dump.py Sat Feb  6 14:47:43 2016
@@ -37,6 +37,8 @@
     ranges = []
     record = dig(domain,"TXT",debug)
     for token in record.split():
+        if token.startswith("redirect="):
+            token = token.replace("redirect=", "redirect:")
         token = token.split(':',1)
         if len(token) == 2:
             key = token[0].lower()
@@ -87,4 +89,4 @@

     for r in set(parsed):
         print r
-
+

Even though unbeautiful it does the trick. Before diff:

$ dig +short -t TXT yandex.com 
"v=spf1 redirect=_spf.yandex.ru"
$ ./spf_dump.py.orig yandex.com
$

After:

$ ./spf_dump.py yandex.com    
5.45.192.0/19
37.140.128.0/18
2a02:6b8:b030::/64
2a02:6b8:0:1000::/52
213.180.223.192/26
2a02:6b8:b011:900::/56
2a02:6b8:b030:1000::/64
37.9.109.0/24
93.158.136.48/28
84.201.128.0/18
87.250.224.0/19
77.88.0.0/18
141.8.132.0/24
2a02:6b8:0:1a2d::/64
95.108.192.0/18
5.255.192.0/18
2a02:6b8:0::/52
95.108.130.0/23
2a02:6b8:0: