Merge pull request #258 from draios/better-list-substitution

Better list substitution

test/falco_tests.yaml

@@ -157,6 +157,68 @@ trace_files: !mux
       - rules/override_nested_list.yaml
     trace_file: trace_files/cat_write.scap
 
+  list_substring:
+    detect: False
+    rules_file:
+      - rules/list_substring.yaml
+    trace_file: trace_files/cat_write.scap
+
+  list_sub_front:
+    detect: True
+    detect_level: WARNING
+    rules_file:
+      - rules/list_sub_front.yaml
+    trace_file: trace_files/cat_write.scap
+
+  list_sub_mid:
+    detect: True
+    detect_level: WARNING
+    rules_file:
+      - rules/list_sub_mid.yaml
+    trace_file: trace_files/cat_write.scap
+
+  list_sub_end:
+    detect: True
+    detect_level: WARNING
+    rules_file:
+      - rules/list_sub_end.yaml
+    trace_file: trace_files/cat_write.scap
+
+  list_sub_bare:
+    detect: True
+    detect_level: WARNING
+    rules_file:
+      - rules/list_sub_bare.yaml
+    trace_file: trace_files/cat_write.scap
+
+  list_sub_whitespace:
+    detect: True
+    detect_level: WARNING
+    rules_file:
+      - rules/list_sub_whitespace.yaml
+    trace_file: trace_files/cat_write.scap
+
+  list_order:
+    detect: True
+    detect_level: WARNING
+    rules_file:
+      - rules/list_order.yaml
+    trace_file: trace_files/cat_write.scap
+
+  macro_order:
+    detect: True
+    detect_level: WARNING
+    rules_file:
+      - rules/macro_order.yaml
+    trace_file: trace_files/cat_write.scap
+
+  rule_order:
+    detect: True
+    detect_level: WARNING
+    rules_file:
+      - rules/rule_order.yaml
+    trace_file: trace_files/cat_write.scap
+
   invalid_rule_output:
     exit_status: 1
     stderr_contains: "Runtime error: Error loading rules:.* Invalid output format 'An open was seen %not_a_real_field': 'invalid formatting token not_a_real_field'. Exiting."

test/rules/list_order.yaml

@@ -0,0 +1,14 @@
+- list: cat_binaries
+  items: [not_cat]
+
+- list: cat_binaries
+  items: [cat]
+
+- macro: is_cat
+  condition: proc.name in (cat_binaries)
+
+- rule: open_from_cat
+  desc: A process named cat does an open
+  condition: evt.type=open and is_cat
+  output: "An open was seen (command=%proc.cmdline)"
+  priority: WARNING

test/rules/list_sub_bare.yaml

@@ -0,0 +1,11 @@
+- list: cat_binaries
+  items: [cat]
+
+- macro: is_cat
+  condition: proc.name=cat_binaries
+
+- rule: open_from_cat
+  desc: A process named cat does an open
+  condition: evt.type=open and is_cat
+  output: "An open was seen (command=%proc.cmdline)"
+  priority: WARNING

test/rules/list_sub_end.yaml

@@ -0,0 +1,11 @@
+- list: cat_binaries
+  items: [cat]
+
+- macro: is_cat
+  condition: proc.name in (ls, cat_binaries)
+
+- rule: open_from_cat
+  desc: A process named cat does an open
+  condition: evt.type=open and is_cat
+  output: "An open was seen (command=%proc.cmdline)"
+  priority: WARNING

test/rules/list_sub_front.yaml

@@ -0,0 +1,11 @@
+- list: cat_binaries
+  items: [cat]
+
+- macro: is_cat
+  condition: proc.name in (cat_binaries, ps)
+
+- rule: open_from_cat
+  desc: A process named cat does an open
+  condition: evt.type=open and is_cat
+  output: "An open was seen (command=%proc.cmdline)"
+  priority: WARNING

test/rules/list_sub_mid.yaml

@@ -0,0 +1,11 @@
+- list: cat_binaries
+  items: [cat]
+
+- macro: is_cat
+  condition: proc.name in (ls, cat_binaries, ps)
+
+- rule: open_from_cat
+  desc: A process named cat does an open
+  condition: evt.type=open and is_cat
+  output: "An open was seen (command=%proc.cmdline)"
+  priority: WARNING

test/rules/list_sub_whitespace.yaml

@@ -0,0 +1,11 @@
+- list: cat_binaries
+  items: [cat]
+
+- macro: is_cat
+  condition: proc.name= cat_binaries or proc.name=nopey
+
+- rule: open_from_cat
+  desc: A process named cat does an open
+  condition: evt.type=open and is_cat
+  output: "An open was seen (command=%proc.cmdline)"
+  priority: WARNING

test/rules/list_substring.yaml

@@ -0,0 +1,8 @@
+- list: my_list
+  items: ['"one string"']
+
+- rule: my_rule
+  desc: my description
+  condition: evt.type=open and fd.name in (file_my_list)
+  output: my output
+  priority: INFO

test/rules/macro_order.yaml

@@ -0,0 +1,14 @@
+- list: cat_binaries
+  items: [cat]
+
+- macro: is_cat
+  condition: proc.name in (not_cat)
+
+- macro: is_cat
+  condition: proc.name in (cat_binaries)
+
+- rule: open_from_cat
+  desc: A process named cat does an open
+  condition: evt.type=open and is_cat
+  output: "An open was seen (command=%proc.cmdline)"
+  priority: WARNING

test/rules/rule_order.yaml

@@ -0,0 +1,17 @@
+- list: cat_binaries
+  items: [cat]
+
+- macro: is_cat
+  condition: proc.name in (cat_binaries)
+
+- rule: open_from_cat
+  desc: A process named cat does an open
+  condition: evt.type=open and proc.name=not_cat
+  output: "An open was seen (command=%proc.cmdline)"
+  priority: WARNING
+
+- rule: open_from_cat
+  desc: A process named cat does an open
+  condition: evt.type=open and is_cat
+  output: "An open was seen (command=%proc.cmdline)"
+  priority: WARNING

userspace/engine/lua/compiler.lua

@@ -325,7 +325,12 @@ end
 function compiler.compile_filter(name, source, macro_defs, list_defs)
 
    for name, items in pairs(list_defs) do
-      source = string.gsub(source, name, table.concat(items, ", "))
+      local begin_name_pat = "^("..name..")([%s(),=])"
+      local mid_name_pat = "([%s(),=])("..name..")([%s(),=])"
+      local end_name_pat = "([%s(),=])("..name..")$"
+      source = string.gsub(source, begin_name_pat, table.concat(items, ", ").."%2")
+      source = string.gsub(source, mid_name_pat, "%1"..table.concat(items, ", ").."%3")
+      source = string.gsub(source, end_name_pat, "%1"..table.concat(items, ", "))
    end
 
    local ast, error_msg = parser.parse_filter(source)