BREAKING: Remove specification field in favour of SLIP-10 path type

src/BIP44CoinTypeNode.ts

@@ -335,7 +335,6 @@ export async function deriveBIP44AddressKey(
   const childNode = await deriveChildNode({
     path,
     node,
-    specification: 'bip32',
   });
 
   return new BIP44Node(childNode);
@@ -414,7 +413,6 @@ export async function getBIP44AddressKeyDeriver(
           : getUnhardenedBIP32NodeToken(address_index),
       ],
       node: actualNode,
-      specification: 'bip32',
     });
 
     return new BIP44Node(slip10Node);

src/BIP44Node.ts

@@ -178,7 +178,6 @@ export class BIP44Node implements BIP44NodeInterface {
       parentFingerprint,
       index,
       curve: 'secp256k1',
-      specification: 'bip32',
     });
 
     return new BIP44Node(node);
@@ -214,7 +213,6 @@ export class BIP44Node implements BIP44NodeInterface {
     const node = await SLIP10Node.fromDerivationPath({
       derivationPath,
       curve: 'secp256k1',
-      specification: 'bip32',
     });
 
     return new BIP44Node(node);

src/SLIP10Node.test.ts

@@ -410,7 +410,6 @@ describe('SLIP10Node', () => {
         privateKey: node.privateKey,
         publicKey: node.publicKey,
         chainCode: node.chainCode,
-        specification: node.specification,
       });
     });
 
@@ -438,20 +437,12 @@ describe('SLIP10Node', () => {
 
     it('initializes a new node from a derivation path with a Uint8Array using ed25519', async () => {
       const node = await SLIP10Node.fromDerivationPath({
-        derivationPath: [
-          defaultBip39BytesToken,
-          BIP44PurposeNodeToken,
-          `bip32:60'`,
-        ],
+        derivationPath: [defaultBip39BytesToken, `slip10:44'`, `slip10:60'`],
         curve: 'ed25519',
       });
 
       const stringNode = await SLIP10Node.fromDerivationPath({
-        derivationPath: [
-          defaultBip39NodeToken,
-          BIP44PurposeNodeToken,
-          `bip32:60'`,
-        ],
+        derivationPath: [defaultBip39NodeToken, `slip10:44'`, `slip10:60'`],
         curve: 'ed25519',
       });
 
@@ -522,9 +513,7 @@ describe('SLIP10Node', () => {
     it('throws an error if no curve is specified', async () => {
       await expect(
         // @ts-expect-error No curve specified, but required in type
-        SLIP10Node.fromDerivationPath({
-          specification: 'bip32',
-        }),
+        SLIP10Node.fromDerivationPath({}),
       ).rejects.toThrow('Invalid curve: Must specify a curve.');
     });
 
@@ -539,18 +528,6 @@ describe('SLIP10Node', () => {
         'Invalid curve: Only the following curves are supported: secp256k1, ed25519.',
       );
     });
-
-    it('throws an error for unsupported specifications', async () => {
-      await expect(
-        SLIP10Node.fromDerivationPath({
-          curve: 'secp256k1',
-          // @ts-expect-error Invalid specification name for type
-          specification: 'foo bar',
-        }),
-      ).rejects.toThrow(
-        'Invalid specification: Must be one of bip32, slip10. Received "foo bar".',
-      );
-    });
   });
 
   describe('derive', () => {
@@ -630,14 +607,14 @@ describe('SLIP10Node', () => {
       const node = await SLIP10Node.fromDerivationPath({
         derivationPath: [
           defaultBip39NodeToken,
-          BIP44PurposeNodeToken,
-          `bip32:3'`,
-          `bip32:0'`,
+          `slip10:44'`,
+          `slip10:3'`,
+          `slip10:0'`,
         ],
         curve: 'ed25519',
       });
 
-      await expect(node.derive(['bip32:0'])).rejects.toThrow(
+      await expect(node.derive(['slip10:0'])).rejects.toThrow(
         'Invalid path: Cannot derive unhardened child keys with ed25519.',
       );
     });
@@ -774,11 +751,7 @@ describe('SLIP10Node', () => {
 
     it('throws an error when trying to get an address for an ed25519 node', async () => {
       const node = await SLIP10Node.fromDerivationPath({
-        derivationPath: [
-          defaultBip39NodeToken,
-          BIP44PurposeNodeToken,
-          `bip32:60'`,
-        ],
+        derivationPath: [defaultBip39NodeToken, `slip10:44'`, `slip10:60'`],
         curve: 'ed25519',
       });
 
@@ -863,7 +836,6 @@ describe('SLIP10Node', () => {
         privateKey: node.privateKey,
         publicKey: node.publicKey,
         chainCode: node.chainCode,
-        specification: node.specification,
       });
 
       expect(JSON.parse(JSON.stringify(nodeJson))).toStrictEqual({
@@ -875,7 +847,6 @@ describe('SLIP10Node', () => {
         privateKey: node.privateKey,
         publicKey: node.publicKey,
         chainCode: node.chainCode,
-        specification: node.specification,
       });
     });
   });

src/SLIP10Node.ts

@@ -9,17 +9,14 @@ import {
 } from './constants';
 import { getCurveByName, SupportedCurve } from './curves';
 import { deriveKeyFromPath } from './derivation';
-import { Specification } from './derivers';
 import { publicKeyToEthAddress } from './derivers/bip32';
 import {
   getBytes,
   getBytesUnsafe,
   getFingerprint,
-  getSpecification,
   isValidInteger,
   validateBIP32Index,
   validateCurve,
-  validateSpecification,
 } from './utils';
 
 /**
@@ -68,21 +65,6 @@ export type JsonSLIP10Node = {
    * The name of the curve used by the node.
    */
   readonly curve: SupportedCurve;
-
-  /**
-   * The specification used to derive this node. Defaults to `bip32` when the
-   * `secp256k1` curve is used, and `slip10` when the `ed25519` curve is used.
-   *
-   * While SLIP-10 and BIP-32 are largely compatible when the `secp256k1` curve
-   * is used, they differ in the way they handle key derivation errors. The
-   * probability of this happening is extremely low, but it is possible. When
-   * full compatibility with one of these specifications is required, this field
-   * should be set to the appropriate value.
-   *
-   * Note that `ed25519` is not supported by BIP-32, so the `bip32`
-   * specification is not available for this curve.
-   */
-  readonly specification: Specification;
 };
 
 export type SLIP10NodeInterface = JsonSLIP10Node & {
@@ -114,7 +96,6 @@ export type SLIP10NodeConstructorOptions = {
   readonly privateKey?: Uint8Array;
   readonly publicKey: Uint8Array;
   readonly curve: SupportedCurve;
-  readonly specification?: Specification;
 };
 
 export type SLIP10ExtendedKeyOptions = {
@@ -126,13 +107,11 @@ export type SLIP10ExtendedKeyOptions = {
   readonly privateKey?: string | Uint8Array;
   readonly publicKey?: string | Uint8Array;
   readonly curve: SupportedCurve;
-  readonly specification?: Specification;
 };
 
 export type SLIP10DerivationPathOptions = {
   readonly derivationPath: RootedSLIP10PathTuple;
   readonly curve: SupportedCurve;
-  readonly specification?: Specification;
 };
 
 export class SLIP10Node implements SLIP10NodeInterface {
@@ -167,7 +146,6 @@ export class SLIP10Node implements SLIP10NodeInterface {
    * specified, this parameter is ignored.
    * @param options.chainCode - The chain code for the node.
    * @param options.curve - The curve used by the node.
-   * @param options.specification - The specification used to derive this node.
    */
   static async fromExtendedKey({
     depth,
@@ -178,12 +156,10 @@ export class SLIP10Node implements SLIP10NodeInterface {
     publicKey,
     chainCode,
     curve,
-    specification = getSpecification(curve),
   }: SLIP10ExtendedKeyOptions) {
     const chainCodeBytes = getBytes(chainCode, BYTES_KEY_LENGTH);
 
     validateCurve(curve);
-    validateSpecification(specification);
     validateBIP32Depth(depth);
     validateBIP32Index(index);
     validateRootIndex(index, depth);
@@ -213,7 +189,6 @@ export class SLIP10Node implements SLIP10NodeInterface {
           privateKey: privateKeyBytes,
           publicKey: await curveObject.getPublicKey(privateKeyBytes),
           curve,
-          specification,
         },
         this.#constructorGuard,
       );
@@ -231,7 +206,6 @@ export class SLIP10Node implements SLIP10NodeInterface {
           chainCode: chainCodeBytes,
           publicKey: publicKeyBytes,
           curve,
-          specification,
         },
         this.#constructorGuard,
       );
@@ -263,17 +237,13 @@ export class SLIP10Node implements SLIP10NodeInterface {
    * @param options.derivationPath - The rooted HD tree path that will be used
    * to derive the key of this node.
    * @param options.curve - The curve used by the node.
-   * @param options.specification - The specification used to derive the key.
-   * Defaults to `slip10`.
    * @returns A new SLIP-10 node.
    */
   static async fromDerivationPath({
     derivationPath,
     curve,
-    specification = getSpecification(curve),
   }: SLIP10DerivationPathOptions) {
     validateCurve(curve);
-    validateSpecification(specification);
 
     if (!derivationPath) {
       throw new Error('Invalid options: Must provide a derivation path.');
@@ -289,16 +259,13 @@ export class SLIP10Node implements SLIP10NodeInterface {
       path: derivationPath,
       depth: derivationPath.length - 1,
       curve,
-      specification,
     });
   }
 
   static #constructorGuard = Symbol('SLIP10Node.constructor');
 
   public readonly curve: SupportedCurve;
 
-  public readonly specification: Specification;
-
   public readonly depth: number;
 
   public readonly masterFingerprint?: number;
@@ -324,7 +291,6 @@ export class SLIP10Node implements SLIP10NodeInterface {
       privateKey,
       publicKey,
       curve,
-      specification = getSpecification(curve),
     }: SLIP10NodeConstructorOptions,
     constructorGuard?: symbol,
   ) {
@@ -341,7 +307,6 @@ export class SLIP10Node implements SLIP10NodeInterface {
     this.privateKeyBytes = privateKey;
     this.publicKeyBytes = publicKey;
     this.curve = curve;
-    this.specification = specification;
 
     Object.freeze(this);
   }
@@ -418,7 +383,6 @@ export class SLIP10Node implements SLIP10NodeInterface {
     return await deriveChildNode({
       path,
       node: this,
-      specification: this.specification,
     });
   }
 
@@ -433,7 +397,6 @@ export class SLIP10Node implements SLIP10NodeInterface {
       privateKey: this.privateKey,
       publicKey: this.publicKey,
       chainCode: this.chainCode,
-      specification: this.specification,
     };
   }
 }
@@ -541,7 +504,6 @@ export function validateRootIndex(index: number, depth: number) {
 type DeriveChildNodeArgs = {
   path: SLIP10PathTuple;
   node: SLIP10Node | BIP44Node | BIP44CoinTypeNode;
-  specification: Specification;
 };
 
 /**
@@ -550,14 +512,11 @@ type DeriveChildNodeArgs = {
  * @param options - The options to use when deriving the child key.
  * @param options.node - The node to derive from.
  * @param options.path - The path to the child node / key.
- * @param options.specification - The specification to use when deriving the
- * child key.
  * @returns The derived key and depth.
  */
 export async function deriveChildNode({
   path,
   node,
-  specification,
 }: DeriveChildNodeArgs): Promise<SLIP10Node> {
   if (path.length === 0) {
     throw new Error(
@@ -574,6 +533,5 @@ export async function deriveChildNode({
     path,
     node,
     depth: newDepth,
-    specification,
   });
 }

src/constants.ts

@@ -22,19 +22,33 @@ export type BIP44Depth = MinBIP44Depth | 1 | 2 | 3 | 4 | MaxBIP44Depth;
 export type AnonymizedBIP39Node = 'm';
 export type BIP39StringNode = `bip39:${string}`;
 export type BIP39Node = BIP39StringNode | Uint8Array;
+
 export type HardenedBIP32Node = `bip32:${number}'`;
 export type UnhardenedBIP32Node = `bip32:${number}`;
 export type BIP32Node = HardenedBIP32Node | UnhardenedBIP32Node;
 
+export type HardenedSLIP10Node = `slip10:${number}'`;
+export type UnhardenedSLIP10Node = `slip10:${number}`;
+export type SLIP10PathNode = HardenedSLIP10Node | UnhardenedSLIP10Node;
+
 export const BIP44PurposeNodeToken = `bip32:44'`;
 
+export const UNPREFIXED_PATH_REGEX = /^\d+$/u;
+
 /**
  * e.g.
  * -  bip32:0
  * -  bip32:0'
  */
 export const BIP_32_PATH_REGEX = /^bip32:\d+'?$/u;
 
+/**
+ * e.g.
+ * -  slip10:0
+ * -  slip10:0'
+ */
+export const SLIP_10_PATH_REGEX = /^slip10:\d+'?$/u;
+
 /**
  * bip39:<SPACE_DELMITED_SEED_PHRASE>
  *
@@ -138,8 +152,12 @@ export type PartialHDPathTuple =
  */
 export type HDPathTuple = RootedHDPathTuple | PartialHDPathTuple;
 
-export type RootedSLIP10PathTuple = readonly [BIP39Node, ...BIP32Node[]];
-export type SLIP10PathTuple = readonly BIP32Node[];
+export type RootedSLIP10PathTuple = readonly [
+  BIP39Node,
+  ...(BIP32Node[] | SLIP10PathNode[]),
+];
+
+export type SLIP10PathTuple = readonly BIP32Node[] | readonly SLIP10PathNode[];
 export type SLIP10Path = RootedSLIP10PathTuple | SLIP10PathTuple;
 
 export type FullHDPathTuple = RootedHDPathTuple5;