Simple SPF Checker via dnspython

spf_check.py

import dns.resolver  # pip install dnspython


class SpfCheck:
    def __init__(self, domain: str) -> None:
        self.domain = domain
        self.spf_record = self.get_spf_record(domain)
        self.parsed_spf = self.get_assets(self.spf_record)
        self.ip_address = self.enumerate_ips(self.spf_record)

    @staticmethod
    def get_spf_record(domain: str) -> str:
        records = dns.resolver.resolve(
            domain, "TXT"
        )
        for record in records:
            record = record.strings[0].decode("utf-8")
            if record.startswith("v=spf1"):
                return record

    @staticmethod
    def enumerate_ips(spf_record: str) -> list:
        ips = []
        spf_values = spf_record.split(" ")
        for item in spf_values:
            if item.startswith("ip4:"):
                ips.append(item.replace("ip4:", ""))
            elif item.startswith("ip6:"):
                ips.append(item.replace("ip6:", ""))
        return ips

    @staticmethod
    def get_assets(spf_record: str) -> list:
        assets = []
        spf_values = spf_record.split(" ")
        # List of all mechanisms as part of SPF standard except for ip4: and ip6:
        mechanisms = ['ptr:', 'include:', 'a:', 'include:', 'mx:', 'exists:', 'all', 'redirect=']
        for item in spf_values:
            # Check for SPF mechanisms in each part of SPF record
            if any(mechanism in item for mechanism in mechanisms):
                assets.append(item)
        return assets