From febb638742bc5f95520e96695f5d0a7ba14ff7d3 Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Mon, 10 Nov 2014 21:48:22 +0100
Subject: [PATCH] check more data for sanity; properly support TLSA and DS
 records

---
 zonemaker/zone.py | 80 ++++++++++++++++++++++++++++++++++++-----------
 1 file changed, 61 insertions(+), 19 deletions(-)

diff --git a/zonemaker/zone.py b/zonemaker/zone.py
index 15add06..5f8e065 100644
--- a/zonemaker/zone.py
+++ b/zonemaker/zone.py
@@ -9,17 +9,26 @@ hour = 60*minute
 day = 24*hour
 week = 7*day
 
-TCP = 'tcp'
-UDP = 'udp'
+REGEX_label = r'[a-zA-Z90-9]([a-zA-Z90-9-]{0,61}[a-zA-Z90-9])?' # max. 63 characters; must not start or end with hyphen
+
+def check_label(label: str) -> str:
+    pattern = r'^{0}$'.format(REGEX_label)
+    if re.match(pattern, label):
+        return label
+    raise Exception(label+" is not a valid label")
 
 def check_hostname(name: str) -> str:
     # check hostname for validity
-    label = r'[a-zA-Z90-9]([a-zA-Z90-9-]{0,61}[a-zA-Z90-9])?' # must not start or end with hyphen
-    pattern = r'^{0}(\.{0})*\.?'.format(label)
+    pattern = r'^{0}(\.{0})*\.?$'.format(REGEX_label)
     if re.match(pattern, name):
         return name
     raise Exception(name+" is not a valid hostname")
 
+def check_hex(data: str) -> str:
+    if re.match('^[a-fA-F0-9]+$', data):
+        return data
+    raise Exception(data+" is not valid hex data")
+
 def time(time: int) -> str:
     if time == 0:
         return "0"
@@ -47,6 +56,19 @@ def column_widths(datas: Sequence, widths: Sequence[int]):
     return result+str(datas[-1])
 
 
+## Enums
+class Protocol:
+    TCP = 'tcp'
+    UDP = 'udp'
+
+class Algorithm:
+    RSA_SHA256 = 8
+
+class Digest:
+    SHA1 = 1
+    SHA256 = 2
+
+
 ## Record types
 class A:
     def __init__(self, address: str) -> None:
@@ -75,8 +97,8 @@ class MX:
 
 class SRV:
     def __init__(self, protocol: str, service: str, name: str, port: int, prio: int, weight: int) -> None:
-        self._service = str(service)
-        self._protocol = str(protocol)
+        self._service = check_label(service)
+        self._protocol = check_label(protocol)
         self._priority = int(prio)
         self._weight = int(weight)
         self._port = int(port)
@@ -88,14 +110,31 @@ class SRV:
 
 
 class TLSA:
-    def __init__(self, protocol: str, port: int, key: str) -> None:
-        # TODO: fix key stuff
+    class Usage:
+        CA = 0 # certificate must pass the usual CA check, with the CA specified by the TLSA record
+        EndEntity_PlusCAs = 1 # the certificate must match the TLSA record *and* pass the usual CA check
+        TrustAnchor = 2 # the certificate must pass a check with the TLSA record giving the (only) trust anchor
+        EndEntity = 3 # the certificate must match the TLSA record
+
+    class Selector:
+        Full = 0
+        SubjectPublicKeyInfo = 1
+    
+    class MatchingType:
+        Exact = 0
+        SHA256 = 1
+        SHA512 = 2
+    
+    def __init__(self, protocol: str, port: int, usage: int, selector: int, matching_type: int, data: str) -> None:
         self._port = int(port)
         self._protocol = str(protocol)
-        self._key = str(key)
+        self._usage = int(usage)
+        self._selector = int(selector)
+        self._matching_type = int(matching_type)
+        self._data = check_hex(data)
     
     def generate_rr(self, owner: str, zone: 'Zone') -> Any:
-        return zone.RR('_{0}._{1}.{2}'.format(self._port, self._protocol, owner), 'TLSA', self._key)
+        return zone.RR('_{0}._{1}.{2}'.format(self._port, self._protocol, owner), 'TLSA', '{0} {1} {2} {3}'.format(self._usage, self._selector, self._matching_type, self._data))
 
 
 class CNAME:
@@ -115,12 +154,14 @@ class NS:
 
 
 class DS:
-    def __init__(self, key: str) -> None:
-        # TODO: fix key stuff
-        self._key = str(key)
+    def __init__(self, tag: int, alg: int, digest: int, key: str) -> None:
+        self._tag = int(tag)
+        self._key = check_hex(key)
+        self._alg = int(alg)
+        self._digest = int(digest)
     
     def generate_rr(self, owner: str, zone: 'Zone') -> Any:
-        return zone.RR(owner, 'DS', self._key)
+        return zone.RR(owner, 'DS', '{0} {1} {2} {3}'.format(self._tag, self._alg, self._digest, self._key))
 
 ## Higher-level classes
 class Name:
@@ -141,11 +182,12 @@ def CName(name: str) -> Name:
     return Name(CNAME(name))
 
 
-def Delegation(name: str, key: str = None) -> Name:
-    records = [NS(name)]
-    if key is not None:
-        records.append(DS(key))
-    return Name(*records)
+def Delegation(name: str) -> Name:
+    return Name(NS(name))
+
+
+def SecureDelegation(name: str, tag: int, alg: int, digest: int, key: str) -> Name:
+    return Name(NS(name), DS(tag, alg, digest, key))
 
 
 class Zone:
-- 
2.30.2