docs: explicitly state which regex flavour is used for redaction

Signed-off-by: Filip Nikolic <[email protected]>

api/v1/tetragon/events.proto

@@ -86,9 +86,9 @@ message CapFilterSet {
 message RedactionFilter {
     // Deprecated, do not use.
     repeated Filter match = 1 [deprecated=true];
-    // Regular expressions to use for redaction. Strings inside capture groups are redacted.
+    // RE2 regular expressions to use for redaction. Strings inside capture groups are redacted.
     repeated string redact = 2;
-    // Regular expression to match binary name. If supplied, redactions will only be applied to matching processes.
+    // RE2 regular expression to match binary name. If supplied, redactions will only be applied to matching processes.
     repeated string binary_regex = 3;
 }
 

docs/content/en/docs/concepts/events.md

@@ -209,10 +209,16 @@ used to string patterns to redact from exported process arguments. These filters
 in JSON and passed to the Tetragon agent via the `--redaction-filters` command
 line flag or the `redactionFilters` Helm value.
 
-To perform redactions, redaction filters define regular expressions in the
-`redact` field. Any capture groups in these regular expressions are redacted and
+To perform redactions, redaction filters define RE2 regular expressions in the
+`redact` field. Any capture groups in these RE2 regular expressions are redacted and
 replaced with `"*****"`.
 
+{{< note >}}
+This feature uses RE2 as its regular expression library. Make sure that you follow
+RE2 regular expression guidelines as you may observe unexpected results otherwise.
+More information on RE2 syntax can be found [here](https://github.com/google/re2/wiki/Syntax).
+{{< /note >}}
+
 {{< warning >}}
 When writing regular expressions in JSON, it is important to escape backslash
 characters. For instance `\Wpasswd\W?` would be written as `{"redact": "\\Wpasswd\\W?"}`.

install/kubernetes/tetragon/values.yaml

@@ -113,13 +113,17 @@ tetragon:
   fieldFilters: |-
 
   # Filters to redact secrets from the args fields in Tetragon events. To perform
-  # redactions, redaction filters define regular expressions in the `redact`
-  # field. Any capture groups in these regular expressions are redacted and
+  # redactions, redaction filters define RE2 regular expressions in the `redact`
+  # field. Any capture groups in these RE2 regular expressions are redacted and
   # replaced with "*****".
   #
   # For more control, you can select which binary or binaries should have their
   # arguments redacted with the `binary_regex` field.
   #
+  # NOTE: This feature uses RE2 as its regular expression library. Make sure that you follow
+  # RE2 regular expression guidelines as you may observe unexpected results otherwise.
+  # More information on RE2 syntax can be found [here](https://github.com/google/re2/wiki/Syntax).
+  #
   # NOTE: When writing regular expressions in JSON, it is important to escape
   # backslash characters. For instance `\Wpasswd\W?` would be written as
   # `{"redact": "\\Wpasswd\\W?"}`.