emailsec.spf

69async def check_spf(sender_ip: str, sender: str) -> SPFCheck:
70    parsed_ip = ipaddress.ip_address(sender_ip)
71    if "@" not in sender:
72        sender = f"postmaster@{sender}"
73    domain = sender.split("@", maxsplit=1)[-1]
74
75    result_builder = partial(SPFCheck, domain=domain, sender_ip=sender_ip)
76
77    dns_resolver = DNSResolver()
78
79    try:
80        res, explanation = await _rec_check_host(
81            dns_resolver, parsed_ip, sender, domain
82        )
83    except errors.Permerror as error:
84        return result_builder(result=SPFResult.PERMERROR, exp=error.args[0])
85    except errors.Temperror as error:
86        return result_builder(result=SPFResult.TEMPERROR, exp=error.args[0])
87    else:
88        return result_builder(result=res, exp=explanation)

39@dataclass
40class SPFCheck:
41    result: SPFResult
42    domain: str
43    sender_ip: str
44    exp: str
45
46    # TODO: figure out how to include the mechanism

17class SPFResult(enum.StrEnum):
18    NONE = "none"
19    NEUTRAL = "neutral"
20    PASS = "pass"
21    FAIL = "fail"
22    SOFTFAIL = "softfail"
23    TEMPERROR = "temperror"
24    PERMERROR = "permerror"
25
26    @classmethod
27    def from_qualifier(cls, q: Qualifier) -> "SPFResult":
28        match q:
29            case Qualifier.PASS:
30                return cls.PASS
31            case Qualifier.FAIL:
32                return cls.FAIL
33            case Qualifier.SOFTFAIL:
34                return cls.SOFTFAIL
35            case Qualifier.NEUTRAL:
36                return cls.NEUTRAL