ctr-savetool

ctr-savetool by yellows8
Tool for generating a Nintendo 3DS savegame MAC and xorpad.
Usage:
--serveradr=<addr> Use the specified server address instead of the default address.
--useserver=<val> This specified whether to use the server. When this is zero, the hashes and keyY are generated, without using the server for the MAC/xorpad generation.

--insave=<path> Input savegame, required when using options --genmac or --decblocks.
--ncch=<path> NCCH to load the 8-byte cleartext accessdesc signature from, for the keyY.
--genxorpad=<path> Generate the save xorpad, and optionally write the xorpad to <path>.
--xorpadsize=<hex-size> Size of the xorpad to generate, when --genxorpad was specified.
--saveid=<hex> SaveID, required for non-gamecard savegames(also required for gamecard v6.0 save crypto).
--imgid=<hex> ImageID, used for extdata when generating the MAC.

--genmac Generate the MAC.
--writemac Write the calculated MAC to the save, when the save MAC and generated MAC don't match.
--decblocks Decrypt the second and third AES blocks from the input savegame with AES-CBC IV=0, for retrieving the CTR used for each block.
--gamecard Process a gamecard savegame, this is the default save-type.
--nandsave Process a NAND savegame, only MAC generation is supported for this.
--extdata Process an extdata image, MAC generation is not supported for Quota.dat.
--sdsave Process a SD /title savegame.
--dbsave=<sd|nand> Process a DB /dbs extdata image.

--accessdescsig=<hex> 8-byte cleartext accessdesc signature, for the keyY.
--romid=<hex> Specify the 4-byte/8-byte ID stored at keyY+8, or the 0x10-byte romID used for generating the keyY.
--keyY=<hex> Raw keyY to use for the savegame.
--CTR=<hex> Raw CTR to use for the savegame.
--imgpath=<path> SD card path to generate the CTR from.
--exefscodehash=<hex> Hash of the ExeFS .code from the main CXI ExeFS header, for the v6.0 save crypto.
--genv60keys=<rsamodulopath> Calculate the v6.0/v7.0 keys for savedata keyY generation and NCCH crypto. If the input file is larger than 0x100-bytes, this will then calculate the keys using the modulus loaded from each byte in the input file.
--rsaexponent=<big-endian hex u32 exponent> Sets the RSA exponent used for the above v6.0+ key generation. The value of this parameter can also be <@filepath>, to load the exponent from a file.