diff options
| -rw-r--r-- | lib/dmarc.ex | 60 |
1 files changed, 27 insertions, 33 deletions
diff --git a/lib/dmarc.ex b/lib/dmarc.ex index 1be5da3..43c1fa4 100644 --- a/lib/dmarc.ex +++ b/lib/dmarc.ex @@ -1,40 +1,34 @@ defmodule Lithium.DMARC do require Logger - def get_dmarc_record(domain) do - with od <- Lithium.Util.PublicSuffix.get_domain(domain), - {:ok, records} <- Lithium.DNS.fetch_txt("_dmarc." <> od) do - - filtered = - records - |> Enum.map(&String.trim/1) - |> Enum.filter(fn found_record -> - # As per Section 7.1, DMARC report authorisations also use a format of "v=DMARC1" - # We should check when we find a tag that it is not *just* a version record. - - # It would technically be invalid to serve this DMARC report authorisation from - # _dmarc.domain.com, however from testing some people do peculiar deployments - # using wildcards and it ends up showing there. - - # For now, we should probably be lenient and just ignore the report authorisation - # instead of tossing the entire DMARC validation process. - trimmed = - found_record - |> String.replace(" ", "") - - String.starts_with?(trimmed, "v=DMARC1;") and trimmed != "v=DMARC1;" - end) - - case filtered do - [] -> - {:error, :nxdomain} - - [record] -> - {:ok, record} + defp select_record(records) do + filtered = + records + |> Enum.map(&String.trim/1) + |> Enum.filter(fn found_record -> + # As per Section 7.1, DMARC report authorisations also use a format of "v=DMARC1" + # We should check when we find a tag that it is not *just* a version record. + trimmed = String.replace(found_record, " ", "") + String.starts_with?(trimmed, "v=DMARC1;") and trimmed != "v=DMARC1;" + end) + + case filtered do + [] -> + {:error, :nxdomain} + [record] -> + {:ok, record} + _ -> + {:error, :multiple_records} + end + end - _ -> - {:error, :multiple_records} - end + def get_dmarc_policy(domain) do + with od <- Lithium.Util.PublicSuffix.get_domain(domain), + {:ok, records} <- Lithium.DNS.fetch_txt("_dmarc." <> od), + {:ok, record } <- select_record(records), + {:ok, policy} <- Lithium.DMARC.Parser.parse_policy(record) + do + {:ok, policy} else error -> error |