Integrate blake ckd into wallet safe.

diff --git a/src/lib/safe.ts b/src/lib/safe.ts
index e5ce41184dbf169ee354be6707b4c4a61b5037b9..89a67b3f3d76934343aa8db9a94a0b968da38a9b 100644 (file)
--- a/src/lib/safe.ts
+++ b/src/lib/safe.ts
@@ -145,7 +145,7 @@ export class Safe {
                        }
                        const prv = this.#type === 'BIP-44'
                                ? await Bip44Ckd.ckd(this.#seed, BIP44_COIN_NANO, index)
-                               : await Blake2bCkd.ckd(this.#seed, index)
+                               : await this.#deriveBlake2bPrivateKey(this.#seed, index)
                        const pub = await NanoNaCl.convert(new Uint8Array(prv))
                        return { index, publicKey: pub.buffer }
                } catch (err) {
@@ -337,6 +337,27 @@ export class Safe {
                }
        }
 
+       /**
+       * Derives account private keys from a wallet seed using the BLAKE2b hashing
+       * algorithm.
+       *
+       * Separately, account public keys are derived from the private key using the
+       * Ed25519 key algorithm, and account addresses are derived from the public key
+       * as described in the Nano documentation.
+       * https://docs.nano.org/integration-guides/the-basics/
+       *
+       * @param {ArrayBuffer} seed - 32-byte secret seed of the wallet
+       * @param {number} index - 4-byte index of account to derive
+       * @returns {ArrayBuffer} Private key for the account
+       */
+       static #deriveBlake2bPrivateKey (seed: ArrayBuffer, index: number): ArrayBuffer {
+               const b = new ArrayBuffer(4)
+               new DataView(b).setUint32(0, index, false)
+               const s = new Uint8Array(seed)
+               const i = new Uint8Array(b)
+               return new Blake2b(32).update(s).update(i).digest().buffer
+       }
+
        static async #createAesKey (purpose: 'encrypt' | 'decrypt', password: ArrayBuffer, keySalt: ArrayBuffer): Promise<CryptoKey> {
                const derivationKey = await crypto.subtle.importKey('raw', password, 'PBKDF2', false, ['deriveBits', 'deriveKey'])
                new Uint8Array(password).fill(0).buffer.transfer()