effective-guacamole

PoC save decryption and re-signing for Animal Crossing: New Horizon. Last updated for 1.2.0

This PoC includes 2 programs:

• save_cryptor
  • decrypts and re-encrypts+signs given save files with a single command
  • example usage (ensure "Header" files are in the same directory):
    • save_cryptor main.dat - decrypts main.dat
    • save_cryptor main.dat.dec - encrypts main.dat.dec
    • save_cryptor Villager0/*.dat - decrypts all .dat in Villager0 folder
• generate_hash_sections
  • automatically generates the hash sections map for use with save_cryptor (prints to stdout)
  • example usage:
    • save_cryptor all_saves_in_this_dir/*.dat && generate_hash_sections all_saves_in_this_dir/*.dat.dec
  • sample output for 1.1.0:

        {
            "postbox", {
                {0x100, 0xb4448c},
            }
        },
        {
            "main", {
                {0x110, 0x1d6d5c},
                {0x1d6e70, 0x323c0c},
                {0x4fab90, 0x35afc},
                {0x530690, 0x362bc},
                {0x566a60, 0x35afc},
                {0x59c560, 0x362bc},
                {0x5d2930, 0x35afc},
                {0x608430, 0x362bc},
                {0x63e800, 0x35afc},
                {0x674300, 0x362bc},
                {0x6aa6d0, 0x35afc},
                {0x6e01d0, 0x362bc},
                {0x7165a0, 0x35afc},
                {0x74c0a0, 0x362bc},
                {0x782470, 0x35afc},
                {0x7b7f70, 0x362bc},
                {0x7ee340, 0x35afc},
                {0x823e40, 0x362bc},
                {0x85a100, 0x26899c},
            }
        },
        {
            "profile", {
                {0x100, 0x6945c},
            }
        },
        {
            "photo_studio_island", {
                {0x100, 0x262bc},
            }
        },
        {
            "personal", {
                {0x110, 0x35afc},
                {0x35c10, 0x362bc},
            }
        },

Build Instructions

Test executable for Windows can be found in releases

To build:

• generate_hash_sections

  • g++ *.cpp -o generate_hash_sections

• save_cryptor

  • g++ *.cpp smhasher/src/MurmurHash3.cpp -lmbedcrypto -o save_cryptor
  • make sure you have libmbedcrypto installed from mbedtls

Credits

• @shadowninja108 for key generation
• @Cuyler36 for save hashing