rspamd: add neural module config (#3833)

Co-authored-by: Georg Lauterbach <44545919+georglauterbach@users.noreply.github.com>
Co-authored-by: Brennan Kinney <5098581+polarathene@users.noreply.github.com>

target/rspamd/local.d/neural.conf

@@ -0,0 +1,42 @@
+#https://github.com/rspamd/rspamd/issues/3099
+rules {
+  "NEURAL_WEEK_1000" {
+    train {
+      max_trains = 1000;
+      max_usages = 50;
+      max_iterations = 25;
+      learning_rate = 0.01,
+      spam_score = 8;
+      ham_score = -2;
+    }
+    symbol_spam = "NEURAL_WEEK_SPAM";
+    symbol_ham = "NEURAL_WEEK_HAM";
+    ann_expire = 300d;
+  }
+  "NEURAL_DAYS_200" {
+    train {
+      max_trains = 200;
+      max_usages = 10;
+      max_iterations = 25;
+      learning_rate = 0.01,
+      spam_score = 8;
+      ham_score = -2;
+    }
+    symbol_spam = "NEURAL_DAYS_SPAM";
+    symbol_ham = "NEURAL_DAYS_HAM";
+    ann_expire = 100d;
+  }
+  "NEURAL_HALF_DAY_50" {
+    train {
+      max_trains = 50;
+      max_usages = 4;
+      max_iterations = 25;
+      learning_rate = 0.01,
+      spam_score = 8;
+      ham_score = -2;
+    }
+    symbol_spam = "NEURAL_HALF_DAY_SPAM";
+    symbol_ham = "NEURAL_HALF_DAY_HAM";
+    ann_expire = 13d;
+  }
+}

target/rspamd/local.d/neural_group.conf

@@ -0,0 +1,26 @@
+symbols = {
+  "NEURAL_WEEK_SPAM" {
+    weight = 3.0; # sample weight
+    description = "Neural network spam (long)";
+  }
+  "NEURAL_WEEK_HAM" {
+    weight = -3.0; # sample weight
+    description = "Neural network ham (long)";
+  }
+  "NEURAL_DAYS_SPAM" {
+    weight = 2.5; # sample weight
+    description = "Neural network spam (medium)";
+  }
+  "NEURAL_DAYS_HAM" {
+    weight = -1.5; # sample weight
+    description = "Neural network ham (medium)";
+  }
+  "NEURAL_HALF_DAY_SPAM" {
+    weight = 2.0; # sample weight
+    description = "Neural network spam (short)";
+  }
+  "NEURAL_HALF_DAY_HAM" {
+    weight = -1.0; # sample weight
+    description = "Neural network ham (short)";
+  }
+}

target/scripts/startup/setup.d/security/rspamd.sh

@@ -20,6 +20,7 @@ function _setup_rspamd() {
     __rspamd__setup_learning
     __rspamd__setup_greylisting
     __rspamd__setup_hfilter_group
+    __rspamd__setup_neural
     __rspamd__setup_check_authenticated
     _rspamd_handle_user_modules_adjustments   # must run last
 
@@ -186,7 +187,6 @@ function __rspamd__setup_default_modules() {
   local DISABLE_MODULES=(
     clickhouse
     elastic
-    neural
     reputation
     spamassassin
     url_redirector
@@ -283,6 +283,23 @@ function __rspamd__setup_hfilter_group() {
   fi
 }
 
+
+# This function handles setup of the neural module (see
+# https://www.rspamd.com/doc/modules/neural.html). This module is experimental
+# but can enhance anti-spam scoring possibly.
+function __rspamd__setup_neural() {
+  if _env_var_expect_zero_or_one 'RSPAMD_NEURAL' && [[ ${RSPAMD_NEURAL} -eq 1 ]]; then
+    __rspamd__log 'debug' 'Enabling Neural module'
+    __rspamd__log 'warn' 'The Neural module is still experimental (in Rspamd) and hence not tested in DMS'
+  else
+    __rspamd__log 'debug' 'Neural module is disabled'
+    rm -f "${RSPAMD_LOCAL_D}/neural.conf"
+    rm -f "${RSPAMD_LOCAL_D}/neural_group.conf"
+    __rspamd__helper__enable_disable_module 'neural' 'false'
+  fi
+}
+
+
 # If 'RSPAMD_CHECK_AUTHENTICATED' is enabled, then content checks for all users, i.e.
 # also for authenticated users, are performed.
 #

target/scripts/startup/variables-stack.sh

@@ -71,6 +71,7 @@ function __environment_variables_general_setup() {
   VARS[RSPAMD_GREYLISTING]="${RSPAMD_GREYLISTING:=0}"
   VARS[RSPAMD_HFILTER]="${RSPAMD_HFILTER:=1}"
   VARS[RSPAMD_HFILTER_HOSTNAME_UNKNOWN_SCORE]="${RSPAMD_HFILTER_HOSTNAME_UNKNOWN_SCORE:=6}"
+  VARS[RSPAMD_NEURAL]="${RSPAMD_NEURAL:=0}"
   VARS[RSPAMD_LEARN]="${RSPAMD_LEARN:=0}"
   VARS[SA_KILL]=${SA_KILL:="10.0"}
   VARS[SPAM_SUBJECT]=${SPAM_SUBJECT:=}