KeyVault

Bonança stores the seed to your HD wallet in what is called a KeyVault, which can be serialized into a json file. This takes inspiration from keystore files, if you are unfamiliar with them consider reading this post.

When serialized, your HD wallet seed is encrypted using a password you define. An example key vault json file structure is as follows:

{
  "vault": {
    "cipher": "aes256-gcm",
    "cipher_params": { "nonce": "287189f34a1433d2de201d08" },
    "cipher_text": "7a34170003c0a7b3ccb75bac28757801a7d9b5e1ff062afa4af5f3c03e7d8982eb1f36ccce87436e42b44ffea6bcf39eba8c15d4e79ee0bf012811fca81ae1e112c0f8ae5d8e43ac8cad1ae961b11207",
    "kdf": "pbkdf2",
    "kdf_params": {
      "key_length": 32,
      "n": 600000,
      "salt": "M6lWvNAGuZBSp9fBGAUEqw"
    },
    "mac": "$argon2id$v=19$m=19456,t=2,p=1$M6lWvNAGuZBSp9fBGAUEqw$/U5VYPmg3+BQj0ttOyPnOUjH7bP23V9/tgvBpovna/8",
    "salt": "M6lWvNAGuZBSp9fBGAUEqw"
  },
  "chain_keys": {
    "Solana": ["AbwHhAquPXvDfxvWEh1b4mG969DQF9wJQSK5k8XKSKtG"],
    "EVM": ["0x50940F0C5779BE15F7ACB12E9b75128e1415BFec"]
  }
}

Breaking down the components:

• cipher is the encryption algorithm used to encrypt your HD wallet seed
• Within cipher_params you find nonce which is an initialization vector for the AES-256-GCM algorithm
• cipher_text is your encrypted seed
• kdf is the key derivation function used (PBKDF2)
• kdf_params are the parameters used in the key derivation function
  • key_length is the length in bytes of the key
  • n is the number of cycles in the algorithm, where 600,000 is used to make encrypting/decrypting time consuming to prevent brute force attacks
  • salt is the password salt
• mac is your hashed and salted password using Argon2 (its parameters are included in the mac string)
• salt again the password salt
• chain_keys these are your public keys for various blockchains

Changes to any of these fields can result in failure to decrypt the seed, and possibly permanent loss of all funds.

The only point of weakness within the KeyVault encryption is your choice of password. If a malicious actor were to get a hold of your json file, they could try to decrypt it by either guessing the password or the seed. Guessing the seed is extremely difficult and unlikely, whereas guessing a password is more doable. This means picking a good password is crucial.

KeyVault includes your public keys within the chain_keys field, which allows you to view your accounts without having to decrypt your KeyVault. There are positives and negatives to this approach, with the main benefit being that you can check wallet balances without supplying your password. The main drawback is that if a malicious actor were to get this file, they would know how valuable breaking the encryption is.