3ds_decrypt_cia
usage
perl 3ds_decrypt_cia.pl [encrypted_cia_file]
install
put 3ds_decrypt_cia.pl, makerom.exe, decrypt.exe in the same directory.
makerom.exe: https://github.com/3DSGuy/Project_CTR/tree/master/makerom
decrypt.exe: https://www.gamebrew.org/wiki/Batch_CIA_3DS_Decryptor