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author | Christian Hesse <mail@eworm.de> | 2023-06-13 20:28:25 +0200 |
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committer | Christian Hesse <mail@eworm.de> | 2023-06-13 20:28:25 +0200 |
commit | 3358dcb0e7a8392c082782bd00077ee502c66968 (patch) | |
tree | 8660a5263935fb87d016a9870a976448d5e4b6e1 /doc | |
parent | 196fe1b0109ff42c9df52a5f8b2314aeff65cd5f (diff) | |
parent | 94b07600baff987161e4f661ff14bddeef9a6174 (diff) |
Merge branch 'fw-addr-lists' into next
Diffstat (limited to 'doc')
-rw-r--r-- | doc/fw-addr-lists.md | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/doc/fw-addr-lists.md b/doc/fw-addr-lists.md new file mode 100644 index 0000000..5805905 --- /dev/null +++ b/doc/fw-addr-lists.md @@ -0,0 +1,90 @@ +Download, import and update firewall address-lists +================================================== + +[⬅️ Go back to main README](../README.md) + +> ℹ️ **Info**: This script can not be used on its own but requires the base +> installation. See [main README](../README.md) for details. + +Description +----------- + +This script downloads, imports and updates firewall address-lists. Its main +purpose is to block attacking ip addresses, spam hosts, command-and-control +servers and similar malicious entities. The default configuration contains +lists from [abuse.ch](https://abuse.ch/) and +[dshield.org](https://dshield.org/), and +lists from [spamhaus.org](https://spamhaus.org/) are prepared. + +The address-lists are updated in place, so after initial import you will not +see situation when the lists are not populated. + +To mitigate man-in-the-middle attacks with altered lists the server's +certificate is checked. + +Requirements and installation +----------------------------- + +Just install the script: + + $ScriptInstallUpdate fw-addr-lists; + +And add two schedulers, first one for initial import after startup, second +one for subsequent updates: + + /system/scheduler/add name="fw-addr-lists@startup" start-time=startup on-event="/system/script/run fw-addr-lists;"; + /system/scheduler/add name="fw-addr-lists" start-time=startup interval=2h on-event="/system/script/run fw-addr-lists;"; + +> ℹ️ **Info**: Modify the interval to your needs, but it is recommended to +> use less than half of the configured timeout for expiration. + +Configuration +------------- + +The configuration goes to `global-config-overlay`, these are the parameters: + +* `FwAddrLists`: a list of firewall address-lists to download and import +* `FwAddrListTimeOut`: the timeout for expiration without renew + +> ℹ️ **Info**: Copy relevant configuration from +> [`global-config`](../global-config.rsc) (the one without `-overlay`) to +> your local `global-config-overlay` and modify it to your specific needs. + +Naming a certificate for a list makes the script verify the server +certificate, so you should add that if possible. Some certificates are +available in my repository and downloaded automatically. Import it manually +(menu `/certificate/`) if missing. + +Create firewall rules to process the packets that are related to addresses +from address-lists. This rejects the packets from and to ip addresses listed +in address-list `block`. + + /ip/firewall/filter/add chain=input src-address-list=block action=reject reject-with=icmp-admin-prohibited; + /ip/firewall/filter/add chain=forward src-address-list=block action=reject reject-with=icmp-admin-prohibited; + /ip/firewall/filter/add chain=forward dst-address-list=block action=reject reject-with=icmp-admin-prohibited; + /ip/firewall/filter/add chain=output dst-address-list=block action=reject reject-with=icmp-admin-prohibited; + +You may want to have an address-list to allow specific addresses, as prepared +with a list `allow`. In fact you can use any list name, just change the +default ones or add your own - matching in configuration and firewall rules. + + /ip/firewall/filter/add chain=input src-address-list=allow action=accept; + /ip/firewall/filter/add chain=forward src-address-list=allow action=accept; + /ip/firewall/filter/add chain=forward dst-address-list=allow action=accept; + /ip/firewall/filter/add chain=output dst-address-list=allow action=accept; + +Modify these for your needs, but **most important**: Move the rules up in +chains and make sure they actually take effect as expected! + +Alternatively handle the packets in firewall's raw section if you prefer: + + /ip/firewall/raw/add chain=prerouting src-address-list=block action=drop; + /ip/firewall/raw/add chain=prerouting dst-address-list=block action=drop; + /ip/firewall/raw/add chain=output dst-address-list=block action=drop; + +> ⚠️ **Warning**: Just again... The order of firewall rules is important. Make +> sure they actually take effect as expected! + +--- +[⬅️ Go back to main README](../README.md) +[⬆️ Go back to top](#top) |