Update README.md

README.md

@@ -62,7 +62,7 @@ If it asks for a distance/priority parameter, input `10`.
 ## Step 2
 Go to your host's server configuration panel and set the rDNS (Reverse DNS) to `mail.yourdomain.com` (obviously, replace `yourdomain.com` with your own). This helps some exotic mail servers to perceive your E-Mails as not spam. After setting up the rDNS, restart the server and run this from your local machine:
 
-```
+```sh
 will@fuckedmachine:~$ ping yourdomain.com
 PING yourdomain.com (x.x.x.x) 56(84) bytes of data.
 64 bytes from mail.yourdomain.com (x.x.x.x): icmp_seq=1 ttl=52 time=13.4 ms
@@ -76,26 +76,26 @@ The 3rd line is the interesting part. It should say `64 bytes from mail.yourdoma
 
 ## Step 3
 SSH onto your shitbox and become root
-```
+```sh
 sudo su
 ```
 
 ## Step 4
 Create your mail user. Note that all users with the `mail` group will be able to send and receive mail.
-```
+```sh
 useradd -m yourname -G mail
 passwd yourname
 ```
 
 OR... If you already have an user that you use (say, `will`), do this instead:
-```
+```sh
 usermod -aG mail will
 ```
 `-aG` tells your stupid server "hey, `mail` is a secondary group for `will`!" `-G` says it's the primary group.
 
 ## Step 5
 Run these commands (don't run `bullmail.sh` quite yet you moron)
-```
+```sh
 git clone https://git.lolcat.ca/lolcat/bullmail
 cd bullmail/script
 chmod +x bullmail.sh
@@ -103,7 +103,7 @@ chmod +x bullmail.sh
 
 ## Step 6
 Edit `bullmail.sh` and change the variables at the top to what matches your configuration. In my case, this is what I used:
-```
+```ini
 #
 # Input your settings here
 #
@@ -119,7 +119,7 @@ I know this is not the first time you're trying to install a mail server. Make s
 
 ## Step 8
 Run the script. Make sure you're root and inside the `script` folder
-```
+```sh
 ./bullmail.sh
 ```
 
@@ -179,6 +179,30 @@ Content-Transfer-Encoding: 7bit
 test
 ```
 
+# Additional configuration
+`rspamd` is your spam filter. You can tweak it manually to instruct it to block specific E-Mails, depending of your situation. For example, this is what I currently use to block incessant phishing E-Mails:
+
+File `/etc/rspamd/local.d/rules.local`
+```cf
+local_rules = {
+  from_mismatch = {
+    expression = "!(from:domain == smtp_from:domain)",
+    score = 5,
+    description = "From domain doesn't match SMTP envelope"
+  },
+  replyto_mismatch = {
+    expression = "replyto && !(replyto:domain == from:domain)",
+    score = 5,
+    description = "Reply-To domain doesn't match From domain"
+  },
+  forged_own_domain_fail_auth = {
+    expression = "(from:domain == 'lolcat.ca') && !(R_DKIM_ALLOW || R_SPF_ALLOW || DMARC_POLICY_ALLOW)",
+    score = 6.0,
+    description = "Email claims to be from our domain but is not properly authenticated"
+  }
+}
+```
+
 # Screenshots
 ## Inbox
 ![Inbox screenshot](img/inbox.png)