feat(client): add RSA/ECDSA support

Author: carlosmiei

README.md

@@ -59,8 +59,20 @@ const client = Binance({
 This library works in both browsers and Node.js environments:
 
 
+### RSA/ECDSA support
 
+This library supports RSA and ED25519 keys out of the box. The usage is straightforward, just provide `privateKey` instead of `apiSecret`.
 
+```js
+
+const apiKey = "ZymCbCxu1LiYIW8IcYSbXQOaAtHaeW3ioCU5qFf5QvUyTfP1runCaY8AwzCaoOaq"
+const privateKey = "-----BEGIN PRIVATE KEY-----\ndMC4CAfAwafYDK2cwaCIEIa+Ax8dMK50wcIcD0Zdf2jaCDoRdaoc7KaadRUh+aLdt\n-----END PRIVATE KEY-----"
+const client = Binance({
+    privateKey,
+    apiKey,
+})
+
+```
 
 ### Proxy Support (Node.js only)
 
@@ -261,6 +273,7 @@ Following examples will use the `await` form, which requires some configuration
 | ----------- | -------- | -------- | -------------------------------------------- |
 | apiKey      | String   | false    | Required when making private calls           |
 | apiSecret   | String   | false    | Required when making private calls           |
+| privateKey  | String   | false    | Required when using RSA/Ed25519 calls        |
 | getTime     | Function | false    | Time generator, defaults to () => Date.now() |
 | httpBase    | String   | false    | Changes the default endpoint                 |
 | httpFutures | String   | false    | Changes the default endpoint                 |

src/http-client.js

@@ -1,6 +1,6 @@
 import zip from 'lodash.zipobject'
 import JSONbig from 'json-bigint'
-import { createHmacSignature } from './signature'
+import { createHmacSignature, createAsymmetricSignature } from './signature'
 
 // Robust environment detection for Node.js vs Browser
 const isNode = (() => {
@@ -230,10 +230,10 @@ const keyCall =
  * @returns {object} The api response
  */
 const privateCall =
-    ({ apiKey, apiSecret, proxy, endpoints, getTime = defaultGetTime, pubCall, testnet }) =>
+    ({ apiKey, apiSecret, privateKey, proxy, endpoints, getTime = defaultGetTime, pubCall, testnet }) =>
     (path, data = {}, method = 'GET', noData, noExtra) => {
-        if (!apiKey || !apiSecret) {
-            throw new Error('You need to pass an API key and secret to make authenticated calls.')
+        if (!apiKey || (!apiSecret && !privateKey)) {
+            throw new Error('You need to pass an API key and secret/privateKey to make authenticated calls.')
         }
 
         return (
@@ -250,10 +250,23 @@ const privateCall =
                 const dataToSign = queryString.substr(1)
 
                 // Create signature (async in browser, sync in Node.js)
-                return createHmacSignature(dataToSign, apiSecret).then(signature => ({
-                    timestamp,
-                    signature,
-                }))
+                if (apiSecret) {
+                    return createHmacSignature(dataToSign, apiSecret).then(signature => ({
+                        timestamp,
+                        signature,
+                    }))
+                } else if (privateKey) {
+                    const sig = createAsymmetricSignature(dataToSign, privateKey)
+                    // .then(signature => ({
+                    //     timestamp,
+                    //     signature,
+                    // }))
+                    return {
+                        timestamp,
+                        signature: sig,
+                    }
+                }
+
             })
             .then(({ timestamp, signature }) => {
                 const newData = noExtra ? data : { ...data, timestamp, signature }

src/signature.js

@@ -1,3 +1,5 @@
+import { sign } from 'crypto'
+
 // Robust environment detection for Node.js vs Browser
 const isNode = (() => {
     // Check for Node.js specific features
@@ -59,3 +61,24 @@ export const createHmacSignature = async (data, secret) => {
         .join('')
     /* eslint-enable no-undef */
 }
+
+export const createAsymmetricSignature = (data, privateKey) => {
+    // Handles RSA and ECDASA (Ed25519) private keys
+    const privateKeyObj = { key: privateKey };
+    const keyObject = nodeCrypto.createPrivateKey(privateKeyObj)
+
+    let signature = '';
+
+    if (privateKey.length > 120) {
+        // RSA key
+        signature = nodeCrypto
+            .sign('RSA-SHA256', Buffer.from(data), keyObject)
+            .toString('base64');
+        // if (encode) signature = encodeURIComponent(signature);
+    } else {
+
+        // Ed25519 key
+        signature = nodeCrypto.sign(null, Buffer.from(data), keyObject).toString('base64');
+    }
+    return signature;
+}