Escape error.log fields ('data', etc.) value

[airween]

This patch escapes the log's data field, similar as mod_security2 does.

The aim is to help to process the content for log parsers.

[airween]

May be we should add the new function here too:

--- a/src/operators/operator.cc
+++ b/src/operators/operator.cc
@@ -112,17 +112,17 @@ std::string Operator::resolveMatchMessage(Transaction *t,
         if (m_couldContainsMacro == false) {
             ret = "Matched \"Operator `" + m_op + "' with parameter `" +
                 utils::string::limitTo(200, m_param) +
-                "' against variable `" + key + "' (Value: `" +
-                utils::string::limitTo(100,
-                    utils::string::toHexIfNeeded(value)) + \
+                "' against variable `" + 
+                utils::string::log_escape_hex(utils::string::limitTo(100, key)) + "' (Value: `" +
+                utils::string::log_escape_hex(utils::string::limitTo(100, value)) +
                 "' )";
         } else {
             std::string p(m_string->evaluate(t));
             ret = "Matched \"Operator `" + m_op + "' with parameter `" +
                 utils::string::limitTo(200, p) +
-                "' against variable `" + key + "' (Value: `" +
-                utils::string::limitTo(100,
-                    utils::string::toHexIfNeeded(value)) +
+                "' against variable `" +
+                utils::string::log_escape_hex(utils::string::limitTo(100, key)) + "' (Value: `" +
+                utils::string::log_escape_hex(utils::string::limitTo(100, value)) +
                 "' )";
         }
     }

I didn't find any occurrence where the user input appears.

There is a similar function toHexIfNeeded(), but it does not encode ".

[martinhsv]

See comments both for when a new function should be called, and comments about specifics about a new function.

[martinhsv]

All good. Thanks.