First persistance work

README.md

@@ -60,4 +60,24 @@ ExecStartPre=/path/to/iptables -w -I INPUT -p all -j reaction
 ExecStopPost=/path/to/iptables -w -D INPUT -p all -j reaction
 ExecStopPost=/path/to/iptables -w -F reaction
 ExecStopPost=/path/to/iptables -w -X reaction
+
+StateDirectory=reaction
+WorkingDirectory=/var/lib/reaction
 ```
+See [reaction.service](./reaction.service) and [reaction.yml](./reaction.yml) for the fully commented examples.
+
+## documentation
+
+### configuration reference
+
+
+`cmd`: note that if program is not in environment's `PATH`, the full path to the command should be given.
+
+`/etc/systemd/system/reaction.service` (again, commented)
+```systemd
+```
+
+### implicit configuration
+
+the working directory of `reaction` will be used to create and read from the embedded [lmdb](https://www.symas.com/lmdb) database.
+if you don't know where to start it, `/var/lib/reaction` should be a sane choice.

app/db.go

@@ -0,0 +1,119 @@
+package app
+
+import (
+	"fmt"
+	"log"
+	"runtime"
+	"time"
+
+	"github.com/bmatsuo/lmdb-go/lmdb"
+)
+
+func numberOfFilters(conf *Conf) int {
+	n := 0
+	for _, s := range conf.Streams {
+		n += len(s.Filters)
+	}
+	return n
+}
+
+type CmdTime struct {
+	cmd []string
+	t   time.Time
+}
+
+// Remove Cmd if last of its set
+type CmdExecuted struct {
+	filter  *Filter
+	pattern *string
+	value   CmdTime
+	err     chan error
+}
+
+// Append Cmd set
+type AppendCmd struct {
+	filter  *Filter
+	pattern *string
+	value   []CmdTime
+	err     chan error
+}
+
+// Append match, remove old ones and check match number
+type AppendMatch struct {
+	filter  *Filter
+	pattern *string
+	t       time.Time
+	ret     chan struct {
+		shouldExec bool
+		err        error
+	}
+}
+
+func databaseHandler(env *lmdb.Env, chCE chan CmdExecuted, chAC chan AppendCmd, chAM chan AppendMatch) {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+	defer env.Close()
+
+	select {
+	case ce := <-chCE:
+		ce = ce
+		// TODO
+	case ac := <-chAC:
+		ac = ac
+		// TODO
+	case am := <-chAM:
+		am = am
+		// TODO
+	}
+}
+
+func initDatabase(conf *Conf) (chan CmdExecuted, chan AppendCmd, chan AppendMatch) {
+	env, err := lmdb.NewEnv()
+	if err != nil {
+		log.Fatalln("LMDB.NewEnv failed")
+	}
+
+	err = env.SetMapSize(1 << 30)
+	if err != nil {
+		log.Fatalln("LMDB.SetMapSize failed")
+	}
+
+	filterNumber := numberOfFilters(conf)
+
+	err = env.SetMaxDBs(filterNumber * 2)
+	if err != nil {
+		log.Fatalln("LMDB.SetMaxDBs failed")
+	}
+
+	matchDBs := make(map[*Filter]lmdb.DBI, filterNumber)
+	cmdDBs := make(map[*Filter]lmdb.DBI, filterNumber)
+
+	runtime.LockOSThread()
+
+	for _, stream := range conf.Streams {
+		for _, filter := range stream.Filters {
+			err = env.UpdateLocked(func(txn *lmdb.Txn) (err error) {
+				matchDBs[filter], err = txn.CreateDBI(fmt.Sprintln("%s.%s.match", stream.name, filter.name))
+				if err != nil {
+					return err
+				}
+
+				cmdDBs[filter], err = txn.CreateDBI(fmt.Sprintln("%s.%s.cmd", stream.name, filter.name))
+				return err
+			})
+			if err != nil {
+				log.Fatalln("LMDB.CreateDBI failed")
+			}
+		}
+	}
+
+	runtime.UnlockOSThread()
+
+	chCE := make(chan CmdExecuted)
+	chAC := make(chan AppendCmd)
+	chAM := make(chan AppendMatch)
+
+	go databaseHandler(env, chCE, chAC, chAM)
+
+	return chCE, chAC, chAM
+}

go.mod

@@ -2,4 +2,7 @@ module reaction
 
 go 1.19
 
-require gopkg.in/yaml.v3 v3.0.1 // indirect
+require (
+	github.com/bmatsuo/lmdb-go v1.8.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)

go.sum

@@ -1,3 +1,5 @@
+github.com/bmatsuo/lmdb-go v1.8.0 h1:ohf3Q4xjXZBKh4AayUY4bb2CXuhRAI8BYGlJq08EfNA=
+github.com/bmatsuo/lmdb-go v1.8.0/go.mod h1:wWPZmKdOAZsl4qOqkowQ1aCrFie1HU8gWloHMCeAUdM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

reaction.service

@@ -0,0 +1,25 @@
+# vim: ft=systemd
+[Unit]
+WantedBy=multi-user.target
+
+[Service]
+ExecStart=/path/to/reaction -c /etc/reaction.yml
+
+# Create an iptables chain for reaction
+ExecStartPre=/path/to/iptables -w -N reaction
+# Set its default to ACCEPT
+ExecStartPre=/path/to/iptables -w -A reaction -j ACCEPT
+# Insert this chain as the first item of the INPUT chain (for incoming connections)
+ExecStartPre=/path/to/iptables -w -I INPUT -p all -j reaction
+
+# Remove the chain from the INPUT chain
+ExecStopPost=/path/to/iptables -w -D INPUT -p all -j reaction
+# Empty the chain
+ExecStopPost=/path/to/iptables -w -F reaction
+# Delete te chain
+ExecStopPost=/path/to/iptables -w -X reaction
+
+# Ask systemd to create /var/lib/reaction (/var/lib/ is implicit)
+StateDirectory=reaction
+# Start reaction in its state directory
+WorkingDirectory=/var/lib/reaction

reaction.test.yml

@@ -0,0 +1,19 @@
+---
+patterns:
+  ip: '(([0-9]{1,3}\.){3}[0-9]{1,3})|([0-9a-fA-F:]{2,90})'
+
+streams:
+  tailDown:
+    cmd: [ "sh", "-c", "echo 'found 1.1.1.1' && sleep 2s && echo 'found 1.1.1.2' && sleep 2s && echo 'found 1.1.1.1' && sleep 1s" ]
+    filters:
+      findIP:
+        regex:
+          - found <ip>
+        retry: 2
+        retry-period: 5s
+        actions:
+          damn:
+            cmd: [ "echo", "<ip>" ]
+          sleepdamn:
+            cmd: [ "echo", "sleep", "<ip>" ]
+            after: 1s

reaction.yml

@@ -1,23 +1,23 @@
 ---
 definitions:
-  - &iptablesban iptables -I reaction 1 -s <ip> -j block
-  - &iptablesunban iptables -D reaction 1 -s <ip> -j block
+  - &iptablesban [ "iptables" "-w" "-I" "reaction" "1" "-s" "<ip>" "-j" "block" ]
+  - &iptablesunban [ "iptables" "-w" "-D" "reaction" "1" "-s" "<ip>" "-j" "block" ]
 
 patterns:
   ip: '(([0-9]{1,3}\.){3}[0-9]{1,3})|([0-9a-fA-F:]{2,90})'
 
 streams:
-  tailDown:
-    cmd: [ "sh", "-c", "echo 'found 1.1.1.1' && sleep 2s && echo 'found 1.1.1.2' && sleep 2s && echo 'found 1.1.1.1' && sleep 1s" ]
+  ssh:
+    cmd: [ "journalctl" "-fu" "sshd.service" ]
     filters:
-      findIP:
+      failedlogin:
         regex:
-          - found <ip>
-        retry: 2
-        retry-period: 5s
+          - authentication failure;.*rhost=<ip>
+        retry: 3
+        retry-period: 6h
         actions:
-          damn:
-            cmd: [ "echo", "<ip>" ]
-          sleepdamn:
-            cmd: [ "echo", "sleep", "<ip>" ]
-            after: 1s
+          ban:
+            cmd: *iptablesban
+          unban:
+            cmd:  *iptablesunban
+            after: 2d