core: add support for CAA queries

saghul · May 13, 2021 · 922b95a · 922b95a
1 parent dfe00f3
commit 922b95a
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Showing 5 changed files with 76 additions and 17 deletions.
diff --git a/docs/channel.rst b/docs/channel.rst
@@ -127,6 +127,7 @@
             - ``QUERY_TYPE_A``
             - ``QUERY_TYPE_AAAA``
             - ``QUERY_TYPE_ANY``
+            - ``QUERY_TYPE_CAA``
             - ``QUERY_TYPE_CNAME``
             - ``QUERY_TYPE_MX``
             - ``QUERY_TYPE_NAPTR``
@@ -149,6 +150,13 @@
               - host
               - ttl
 
+            - CAA: (list of) ``ares_query_caa_result``, fields:
+
+              - critical
+              - property
+              - value
+              - ttl
+
             - CNAME: ``ares_query_cname_result``, fields:
 
               - cname

diff --git a/src/_cffi_src/build_cares.py b/src/_cffi_src/build_cares.py
@@ -77,6 +77,7 @@
 #define T_A  ...
 #define T_AAAA  ...
 #define T_ANY  ...
+#define T_CAA ...
 #define T_CNAME ...
 #define T_MX  ...
 #define T_NAPTR ...
@@ -252,6 +253,15 @@
   int             ttl;
 };
 
+struct ares_caa_reply {
+  struct ares_caa_reply  *next;
+  int                     critical;
+  unsigned char          *property;
+  size_t                  plength;
+  unsigned char          *value;
+  size_t                  length;
+};
+
 struct ares_srv_reply {
   struct ares_srv_reply  *next;
   char                   *host;
@@ -492,6 +502,10 @@
                                        struct ares_addr6ttl *addrttls,
                                        int *naddrttls);
 
+int ares_parse_caa_reply(const unsigned char* abuf,
+                         int alen,
+                         struct ares_caa_reply** caa_out);
+
 int ares_parse_ptr_reply(const unsigned char *abuf,
                                       int alen,
                                       const void *addr,
@@ -589,4 +603,3 @@
 ffi = cffi.FFI()
 ffi.cdef(PLATFORM_TYPES + TYPES + FUNCTIONS + CALLBACKS)
 ffi.set_source('_cares', INCLUDES)
-
diff --git a/src/pycares/__init__.py b/src/pycares/__init__.py
@@ -54,24 +54,25 @@
 
 exported_pycares_symbols_map = {
     # Query types
-    "QUERY_TYPE_A" : "T_A",
-    "QUERY_TYPE_AAAA" : "T_AAAA",
-    "QUERY_TYPE_ANY" : "T_ANY",
+    "QUERY_TYPE_A"     : "T_A",
+    "QUERY_TYPE_AAAA"  : "T_AAAA",
+    "QUERY_TYPE_ANY"   : "T_ANY",
+    "QUERY_TYPE_CAA"   : "T_CAA",
     "QUERY_TYPE_CNAME" : "T_CNAME",
-    "QUERY_TYPE_MX" : "T_MX",
+    "QUERY_TYPE_MX"    : "T_MX",
     "QUERY_TYPE_NAPTR" : "T_NAPTR",
-    "QUERY_TYPE_NS" : "T_NS",
-    "QUERY_TYPE_PTR" : "T_PTR",
-    "QUERY_TYPE_SOA" : "T_SOA",
-    "QUERY_TYPE_SRV" : "T_SRV",
-    "QUERY_TYPE_TXT" : "T_TXT",
+    "QUERY_TYPE_NS"    : "T_NS",
+    "QUERY_TYPE_PTR"   : "T_PTR",
+    "QUERY_TYPE_SOA"   : "T_SOA",
+    "QUERY_TYPE_SRV"   : "T_SRV",
+    "QUERY_TYPE_TXT"   : "T_TXT",
 
     # Query classes
-    "QUERY_CLASS_IN": "C_IN",
+    "QUERY_CLASS_IN"   : "C_IN",
     "QUERY_CLASS_CHAOS": "C_CHAOS",
-    "QUERY_CLASS_HS": "C_HS",
-    "QUERY_CLASS_NONE":"C_NONE",
-    "QUERY_CLASS_ANY": "C_ANY",
+    "QUERY_CLASS_HS"   : "C_HS",
+    "QUERY_CLASS_NONE" :"C_NONE",
+    "QUERY_CLASS_ANY"  : "C_ANY",
 }
 
 for k, v in exported_pycares_symbols_map.items():
@@ -131,7 +132,7 @@ def _query_cb(arg, status, timeouts, abuf, alen):
     if status == _lib.ARES_SUCCESS:
         if query_type == _lib.T_ANY:
             result = []
-            for qtype in (_lib.T_A, _lib.T_AAAA, _lib.T_CNAME, _lib.T_MX, _lib.T_NAPTR, _lib.T_NS, _lib.T_PTR, _lib.T_SOA, _lib.T_SRV, _lib.T_TXT):
+            for qtype in (_lib.T_A, _lib.T_AAAA, _lib.T_CAA, _lib.T_CNAME, _lib.T_MX, _lib.T_NAPTR, _lib.T_NS, _lib.T_PTR, _lib.T_SOA, _lib.T_SRV, _lib.T_TXT):
                 r, status = parse_result(qtype, abuf, alen)
                 if status not in (None, _lib.ARES_ENODATA, _lib.ARES_EBADRESP):
                     result = None
@@ -184,6 +185,20 @@ def parse_result(query_type, abuf, alen):
         else:
             result = [ares_query_aaaa_result(addrttls[i]) for i in range(naddrttls[0])]
             status = None
+    elif query_type == _lib.T_CAA:
+        caa_reply = _ffi.new("struct ares_caa_reply **")
+        parse_status = _lib.ares_parse_caa_reply(abuf, alen, caa_reply)
+        if parse_status != _lib.ARES_SUCCESS:
+            result = None
+            status = parse_status
+        else:
+            result = []
+            caa_reply_ptr = caa_reply[0]
+            while caa_reply_ptr != _ffi.NULL:
+                result.append(ares_query_caa_result(caa_reply_ptr))
+                caa_reply_ptr = caa_reply_ptr.next
+            _lib.ares_free_data(caa_reply[0])
+            status = None
     elif query_type == _lib.T_CNAME:
         host = _ffi.new("struct hostent **")
         parse_status = _lib.ares_parse_a_reply(abuf, alen, host, _ffi.NULL, _ffi.NULL)
@@ -309,7 +324,7 @@ def parse_result(query_type, abuf, alen):
 
 
 class Channel:
-    __qtypes__ = (_lib.T_A, _lib.T_AAAA, _lib.T_ANY, _lib.T_CNAME, _lib.T_MX, _lib.T_NAPTR, _lib.T_NS, _lib.T_PTR, _lib.T_SOA, _lib.T_SRV, _lib.T_TXT)
+    __qtypes__ = (_lib.T_A, _lib.T_AAAA, _lib.T_ANY, _lib.T_CAA, _lib.T_CNAME, _lib.T_MX, _lib.T_NAPTR, _lib.T_NS, _lib.T_PTR, _lib.T_SOA, _lib.T_SRV, _lib.T_TXT)
     __qclasses__ = (_lib.C_IN, _lib.C_CHAOS, _lib.C_HS, _lib.C_NONE, _lib.C_ANY)
 
     def __init__(self,
@@ -641,6 +656,17 @@ def __init__(self, ares_addrttl):
         self.ttl = ares_addrttl.ttl
 
 
+class  ares_query_caa_result(AresResult):
+    __slots__ = ('critical', 'property', 'value', 'ttl')
+    type = 'CAA'
+
+    def __init__(self, caa):
+        self.critical = caa.critical
+        self.property = maybe_str(_ffi.string(caa.property, caa.plength))
+        self.value = maybe_str(_ffi.string(caa.value, caa.length))
+        self.ttl = -1
+
+
 class ares_query_cname_result(AresResult):
     __slots__ = ('cname', 'ttl')
     type = 'CNAME'
@@ -827,4 +853,3 @@ def __init__(self, ares_addrinfo):
 __all__ = exported_pycares_symbols + list(exported_pycares_symbols_map.keys()) + ['AresError', 'Channel', 'errno', '__version__']
 
 del exported_pycares_symbols, exported_pycares_symbols_map
-
diff --git a/src/pycares/__main__.py b/src/pycares/__main__.py
@@ -40,6 +40,8 @@ def cb(result, error):
             txt = '%s\t\t%d\tIN\t%s' % (hostname, r.ttl, r.type)
             if r.type in ('A', 'AAAA'):
                 parts.append('%s\t%s' % (txt, r.host))
+            elif r.type == 'CAA':
+                parts.append('%s\t%d %s "%s"' % (txt, r.critical, r.property, r.value))
             elif r.type == 'CNAME':
                 parts.append('%s\t%s' % (txt, r.cname))
             elif r.type == 'MX':

diff --git a/tests/tests.py b/tests/tests.py
@@ -230,6 +230,17 @@ def cb(result, errorno):
             self.assertEqual(type(r), pycares.ares_query_aaaa_result)
             self.assertNotEqual(r.host, None)
 
+    def test_query_caa(self):
+        self.result, self.errorno = None, None
+        def cb(result, errorno):
+            self.result, self.errorno = result, errorno
+        self.channel.query('wikipedia.org', pycares.QUERY_TYPE_CAA, cb)
+        self.wait()
+        self.assertNoError(self.errorno)
+        self.assertTrue(len(self.result) > 0)
+        for r in self.result:
+            self.assertEqual(type(r), pycares.ares_query_caa_result)
+
     def test_query_cname(self):
         self.result, self.errorno = None, None
         def cb(result, errorno):