Decrypting wpa_supplicant.conf on Samsung Galaxy mobiles
Use wpa_supplicant's wpa_passphrase tool to create your own "real" psk. Actually, the plain-text psk (double-quoted) must be processed at every startup and config reload to generate the real, 64 hex-digit (256-bit) psk. So, using wpa_passphrase to manually create the fully-processed PSK actually optimizes wpa_supplicant's startup &amp; config reload time. :)

About decrypting them... wpa_supplicant uses an AES-based cipher, which is well respected. I think TKIP is deprecated and possibly exploitable.