checkdmarc

A Python module and command line utility for validating SPF and DMARC DNS records

usage: checkdmarc [-h] [-d] [-f FORMAT] [-o OUTPUT]
              [-n NAMESERVER [NAMESERVER ...]] [-t TIMEOUT] [-v]
              [-w WAIT]
              domain [domain ...]

Validates and parses SPF amd DMARC DNS records

positional arguments:
  domain                one or ore domains, or a single path to a file
                        containing a list of domains

optional arguments:
  -h, --help            show this help message and exit
  -d, --descriptions    include descriptions of DMARC tags in the JSON output
  -f FORMAT, --format FORMAT
                        specify JSON or CSV output format
  -o OUTPUT, --output OUTPUT
                        output to a file path rather than printing to the
                        screen
  -n NAMESERVER [NAMESERVER ...], --nameserver NAMESERVER [NAMESERVER ...]
                        nameservers to query (Default is Cloudflare's)
  -t TIMEOUT, --timeout TIMEOUT
                        number of seconds to wait for an answer from DNS
                        (default 6.0)
  -v, --version         show program's version number and exit
  -w WAIT, --wait WAIT  number os seconds to wait between processing domains
                        (default 0.0)

$ checkdmarc fbi.gov

{
  "domain": "fbi.gov",
  "base_domain": "fbi.gov",
  "mx": {
    "hosts": [
      {
        "preference": 10,
        "hostname": "mx-east.fbi.gov",
        "addresses": [
          "153.31.160.5"
        ]
      }
    ],
    "warnings": []
  },
  "spf": {
    "record": "v=spf1 +mx ip4:153.31.0.0/16 -all",
    "valid": true,
    "dns_lookups": 1,
    "warnings": [],
    "parsed": {
      "pass": [
        {
          "value": "mx-east.fbi.gov",
          "mechanism": "mx"
        },
        {
          "value": "153.31.0.0/16",
          "mechanism": "ip4"
        }
      ],
      "neutral": [],
      "softfail": [],
      "fail": [],
      "include": [],
      "redirect": null,
      "exp": null,
      "all": "fail"
    }
  },
  "dmarc": {
    "record": "v=DMARC1; p=reject; adkim=r; aspf=r; rua=mailto:dmarc-feedback@fbi.gov; ruf=mailto:dmarc-feedback@fbi.gov; pct=100",
    "valid": true,
    "location": "fbi.gov",
    "warnings": [],
    "tags": {
      "v": {
        "value": "DMARC1",
        "explicit": true
      },
      "p": {
        "value": "reject",
        "explicit": true
      },
      "adkim": {
        "value": "r",
        "explicit": true
      },
      "aspf": {
        "value": "r",
        "explicit": true
      },
      "rua": {
        "value": [
          {
            "scheme": "mailto",
            "address": "dmarc-feedback@fbi.gov",
            "size_limit": null
          }
        ],
        "explicit": true
      },
      "ruf": {
        "value": [
          {
            "scheme": "mailto",
            "address": "dmarc-feedback@fbi.gov",
            "size_limit": null
          }
        ],
        "explicit": true
      },
      "pct": {
        "value": 100,
        "explicit": true
      },
      "fo": {
        "value": [
          "0"
        ],
        "explicit": false
      },
      "rf": {
        "value": [
          "afrf"
        ],
        "explicit": false
      },
      "ri": {
        "value": 86400,
        "explicit": false
      },
      "sp": {
        "value": "reject",
        "explicit": false
      }
    }
  }
}

Installation

checkdmarc requires Python 3.

On Debian or Ubuntu systems, run:

$ sudo apt-get install python3-pip

Python 3 installers for Windows and macOS can be found at https://www.python.org/downloads/

To install or upgrade to the latest stable release of checkdmarc on macOS or Linux, run

$ sudo -H pip3 install -U checkdmarc

Or, install the latest development release directly from GitHub:

$ sudo -H pip3 install -U git+https://github.com/domainaware/checkdmarc.git

Note

On Windows, pip3 is pip, even with Python 3. So on Windows, simply substitute pip as an administrator in place of sudo pip3, in the above commands.

Documentation

https://domainaware.github.io/checkdmarc

Bug reports

Please report bugs on the GitHub issue tracker

https://github.com/domainaware/checkdmarc/issues