Which config file stores cracking modes and rules on Linux?

• A. john.conf
• B. john.ini
• C. john.rc
• D. john.json

Answer: (A)

John the Ripper on Linux uses a configuration file named john.conf to define how you crack passwords and which transformation rules to apply. This file outlines the cracking modes (such as Single, Wordlist, and Incremental) and the rules that mutate candidate passwords (for example, applying case changes, substitutions, or suffixes/prefixes). That makes it the place where both the methods for generating guesses and the logic for transforming them live.

Why this fits best: john.conf is the standard Linux config you’ll edit or view to customize cracking behavior, and it’s the file the tool reads for modes and rules. Other options like john.ini are Windows-oriented, john.rc isn’t a typical John configuration, and john.json isn’t used by John the Ripper for this purpose, so they wouldn’t store the Linux cracking modes and rules.