Rspamd: replace reject_unknown_client_hostname with Rspamd HFILTER_HOSTNAME_UNKNOWN and make it configurable (#3248)

docs/content/config/environment.md

@@ -363,6 +363,21 @@ When enabled,
 - **0** => Disabled
 - 1 => Enabled
 
+##### RSPAMD_HFILTER
+
+Can be used to enable or disable the [Hfilter group module][rspamd-docs-hfilter-group-module]. This is used by DMS to adjust the `HFILTER_HOSTNAME_UNKNOWN` symbol, increasing it's default weight to act similar to Postfix's `reject_unknown_client_hostname`, without the need to outright reject a message.
+
+- 0 => Disabled
+- **1** => Enabled
+
+[rspamd-docs-hfilter-group-module]: https://www.rspamd.com/doc/modules/hfilter.html
+
+##### RSPAMD_HFILTER_HOSTNAME_UNKNOWN_SCORE
+
+Can be used to control the score when the [`HFILTER_HOSTNAME_UNKNOWN` symbol](#rspamd_hfilter) applies. A higher score is more punishing. Setting it to 15 (the default score for rejecting an e-mail) is equivalent to rejecting the email when the check fails.
+
+Default: 6 (which corresponds to the `add_header` action)
+
 #### Reports
 
 ##### PFLOGSUMM_TRIGGER

docs/content/config/security/rspamd.md

@@ -25,8 +25,10 @@ The following environment variables are related to Rspamd:
 1. [`ENABLE_RSPAMD`](../environment.md#enable_rspamd)
 2. [`ENABLE_RSPAMD_REDIS`](../environment.md#enable_rspamd_redis)
 3. [`RSPAMD_GREYLISTING`](../environment.md#rspamd_greylisting)
-4. [`RSPAMD_LEARN`](../environment.md#rspamd_learn)
-5. [`MOVE_SPAM_TO_JUNK`](../environment.md#move_spam_to_junk)
+4. [`RSPAMD_HFILTER`](../environment.md#rspamd_hfilter)
+5. [`RSPAMD_HFILTER_HOSTNAME_UNKNOWN_SCORE`](../environment.md#rspamd_hfilter_hostname_unknown_score)
+6. [`RSPAMD_LEARN`](../environment.md#rspamd_learn)
+7. [`MOVE_SPAM_TO_JUNK`](../environment.md#move_spam_to_junk)
 
 With these variables, you can enable Rspamd itself and you can enable / disable certain features related to Rspamd.