cloudfloordns.models.record

  1from itertools import chain
  2from typing import Literal, Optional
  3
  4from pydantic import BaseModel
  5
  6TYPES_VALUES = Literal[
  7    "A",
  8    "AAAA",
  9    "ALIAS",
 10    "CNAME",
 11    "HINFO",
 12    "MX",
 13    "NS",
 14    "PTR",
 15    "RP",
 16    "SRV",
 17    "CAA",
 18    "TXT",
 19    "REDIRECT://",
 20    # For comparison, the following are valid on Cloudflare
 21    # "SOA",
 22    # "DS",
 23    # "DNSKEY",
 24    # "LOC",
 25    # "NAPTR",
 26    # "SSHFP",
 27    # "SVCB",
 28    # "TSLA",
 29    # "URI",
 30    # "SPF",
 31]
 32
 33FULL_COMPARISON = {
 34    "A",
 35    "AAAA",
 36    "ALIAS",
 37    "CNAME",
 38}
 39
 40UNIQUE_BY_NAME = {"HINFO", "MX", "NS", "PTR", "RP", "SRV", "CAA", "TXT", "REDIRECT://"}
 41
 42REDIRECT_SERVERS = [
 43    "dforward.mtgsy.net.",
 44]
 45REDIRECT_SERVERS_IP = [
 46    "50.31.0.12",
 47]
 48
 49REDIRECT_VALUES = list(
 50    chain(
 51        (("CNAME", value) for value in REDIRECT_SERVERS),
 52        (("A", ip) for ip in REDIRECT_SERVERS_IP),
 53    )
 54)
 55
 56
 57class Record(BaseModel):
 58    """
 59    Pydantic model
 60    """
 61
 62    name: str
 63    type: str
 64    data: str
 65    id: Optional[str] = None
 66    zone: Optional[str] = None
 67    aux: str = "0"
 68    ttl: int = 3600
 69    active: Literal["Y", "N"] = "Y"
 70    # isfwd: str = "0"
 71    # cc: str = None
 72    # lbType: str = "0"
 73
 74    class Config:
 75        populate_by_name = True
 76        extra = "allow"
 77
 78    @property
 79    def identifier(self) -> str:
 80        """
 81        This method returns an identifer for the record that does not depend on its remote id
 82        """
 83        identifier = f"{self.name}/{self.type}"
 84        if self.type in FULL_COMPARISON:
 85            identifier = f"{identifier}/{self.data}"
 86        return identifier
 87
 88    def __hash__(self):
 89        return hash(self.identifier)
 90
 91    def is_same(self, right: "Record") -> bool:
 92        """
 93        This method check the identity (e.g. same id if defined, or same name/name+value)
 94        """
 95        if not isinstance(right, Record):
 96            return NotImplemented
 97        if self.id and right.id:
 98            return self.id == right.id
 99        if (self.name, self.type) != (right.name, right.type):
100            return False
101        if self.type in FULL_COMPARISON:
102            return self.data == right.data
103        return True
104
105    @property
106    def contains_spf_definition(self) -> bool:
107        # RFC states that we only have one spf record on the APEX
108        # But we may defined other records with spf definition to be included elsewhere.
109        return all((self.type == "TXT", "v=spf" in self.data.lower()))
110
111    @property
112    def is_apex(self) -> bool:
113        name = self.name.strip()
114        return name in ("", "@")  # or name.endswith(".")
115
116    @property
117    def is_redirect(self) -> bool:
118        data = (self.type.strip(), self.data.strip())
119        return data in REDIRECT_VALUES
120
121    @property
122    def is_spf(self) -> bool:
123        # RFC:
124        # https://www.rfc-editor.org/rfc/rfc6242#section-4.1
125        # https://datatracker.ietf.org/doc/html/rfc7208#section-4.5
126        # NOTE: There should be only 1 apex spf record,
127        # but we can create other spf record (e.g. spf1.mydomain.com) and include it in the apex
128        # (alternatively, we can define spf records with CNAME or even NS records)
129        return all((not self.name, self.contains_spf_definition))
130
131    @property
132    def is_dkim(self) -> bool:
133        return all(
134            (
135                "._domainkey" in self.name,
136                self.type == "TXT",
137                "v=dkim" in self.data.lower(),
138            )
139        )
140
141    @property
142    def is_dmarc(self) -> bool:
143        return all(
144            ("_dmarc" in self.name, self.type == "TXT", "v=dmarc" in self.data.lower())
145        )
146
147    @property
148    def is_null_mx(self) -> bool:
149        return (
150            self.type.upper() == "MX"
151            and (self.name.endswith(".") or self.name in ("", "@"))
152            and self.data in ("", ".")
153        )
154
155    @property
156    def is_standard(self) -> bool:
157        """
158        Return True if the record is a standard one, False otherwise.
159        A record is a standard one if it it:
160        - A mail hardening record (SPF/DKIM/DMARC/Null MX)
161        - An apex NS record
162        """
163        return any(
164            (
165                self.is_null_mx,
166                self.is_spf,
167                self.is_dkim,
168                self.is_dmarc,
169                (self.type.upper() == "NS" and self.is_apex),
170            )
171        )