Allow specifying BIP44 account when importing from USB (#360)

src/cryptoadvance/specter/hwi_rpc.py

@@ -140,13 +140,13 @@ def send_pin(self, pin='', device_type=None, path=None, passphrase='', chain='')
             raise Exception("Invalid HWI device type %s, send_pin is only supported for Trezor and Keepkey devices" % device_type)
 
     @locked(hwilock)
-    def extract_xpubs(self, device_type=None, path=None, fingerprint=None, passphrase='', chain=''):
+    def extract_xpubs(self, account=0, device_type=None, path=None, fingerprint=None, passphrase='', chain=''):
         with self._get_client(device_type=device_type,
                               fingerprint=fingerprint,
                               path=path,
                               passphrase=passphrase,
                               chain=chain) as client:
-            xpubs = self._extract_xpubs_from_client(client)
+            xpubs = self._extract_xpubs_from_client(client, account)
         return xpubs
 
     @locked(hwilock)
@@ -230,7 +230,7 @@ def _get_client(self, device_type=None, path=None, fingerprint=None, passphrase=
             else:
                 raise Exception('The device could not be found. Please check it is properly connected and try again')
 
-    def _extract_xpubs_from_client(self, client):
+    def _extract_xpubs_from_client(self, client, account=0):
         try:
             xpubs = ""
             # Client will be configured for testnet if our Specter instance is
@@ -246,47 +246,63 @@ def _extract_xpubs_from_client(self, client):
             #   https://github.com/satoshilabs/slips/blob/master/slip-0132.md
 
             # Extract nested Segwit
-            xpub = client.get_pubkey_at_path('m/49h/0h/0h')['xpub']
+            xpub = client.get_pubkey_at_path(
+                'm/49h/0h/{}h'.format(account)
+            )['xpub']
             ypub = convert_xpub_prefix(xpub, b'\x04\x9d\x7c\xb2')
-            xpubs += "[%s/49'/0'/0']%s\n" % (master_fpr, ypub)
+            xpubs += "[{}/49'/0'/{}']{}\n".format(master_fpr, account, ypub)
 
             # native Segwit
-            xpub = client.get_pubkey_at_path('m/84h/0h/0h')['xpub']
+            xpub = client.get_pubkey_at_path(
+                'm/84h/0h/{}h'.format(account)
+            )['xpub']
             zpub = convert_xpub_prefix(xpub, b'\x04\xb2\x47\x46')
-            xpubs += "[%s/84'/0'/0']%s\n" % (master_fpr, zpub)
+            xpubs += "[{}/84'/0'/{}']{}\n".format(master_fpr, account, zpub)
 
             # Multisig nested Segwit
-            xpub = client.get_pubkey_at_path('m/48h/0h/0h/1h')['xpub']
+            xpub = client.get_pubkey_at_path(
+                'm/48h/0h/{}h/1h'.format(account)
+            )['xpub']
             Ypub = convert_xpub_prefix(xpub, b'\x02\x95\xb4\x3f')
-            xpubs += "[%s/48'/0'/0'/1']%s\n" % (master_fpr, Ypub)
+            xpubs += "[{}/48'/0'/{}'/1']{}\n".format(master_fpr, account, Ypub)
 
             # Multisig native Segwit
-            xpub = client.get_pubkey_at_path('m/48h/0h/0h/2h')['xpub']
+            xpub = client.get_pubkey_at_path(
+                'm/48h/0h/{}h/2h'.format(account)
+            )['xpub']
             Zpub = convert_xpub_prefix(xpub, b'\x02\xaa\x7e\xd3')
-            xpubs += "[%s/48'/0'/0'/2']%s\n" % (master_fpr, Zpub)
+            xpubs += "[{}/48'/0'/{}'/2']{}\n".format(master_fpr, account, Zpub)
 
             # And testnet
             client.is_testnet = True
 
             # Testnet nested Segwit
-            xpub = client.get_pubkey_at_path('m/49h/1h/0h')['xpub']
+            xpub = client.get_pubkey_at_path(
+                'm/49h/1h/{}h'.format(account)
+            )['xpub']
             upub = convert_xpub_prefix(xpub, b'\x04\x4a\x52\x62')
-            xpubs += "[%s/49'/1'/0']%s\n" % (master_fpr, upub)
+            xpubs += "[{}/49'/1'/{}']{}\n".format(master_fpr, account, upub)
 
             # Testnet native Segwit
-            xpub = client.get_pubkey_at_path('m/84h/1h/0h')['xpub']
+            xpub = client.get_pubkey_at_path(
+                'm/84h/1h/{}h'.format(account)
+            )['xpub']
             vpub = convert_xpub_prefix(xpub, b'\x04\x5f\x1c\xf6')
-            xpubs += "[%s/84'/1'/0']%s\n" % (master_fpr, vpub)
+            xpubs += "[{}/84'/1'/{}']{}\n".format(master_fpr, account, vpub)
 
             # Testnet multisig nested Segwit
-            xpub = client.get_pubkey_at_path('m/48h/1h/0h/1h')['xpub']
+            xpub = client.get_pubkey_at_path(
+                'm/48h/1h/{}h/1h'.format(account)
+            )['xpub']
             Upub = convert_xpub_prefix(xpub, b'\x02\x42\x89\xef')
-            xpubs += "[%s/48'/1'/0'/1']%s\n" % (master_fpr, Upub)
+            xpubs += "[{}/48'/1'/{}'/1']{}\n".format(master_fpr, account, Upub)
 
             # Testnet multisig native Segwit
-            xpub = client.get_pubkey_at_path('m/48h/1h/0h/2h')['xpub']
+            xpub = client.get_pubkey_at_path(
+                'm/48h/1h/{}h/2h'.format(account)
+            )['xpub']
             Vpub = convert_xpub_prefix(xpub, b'\x02\x57\x54\x83')
-            xpubs += "[%s/48'/1'/0'/2']%s\n" % (master_fpr, Vpub)
+            xpubs += "[{}/48'/1'/{}'/2']{}\n".format(master_fpr, account, Vpub)
 
             # Do proper cleanup otherwise have to reconnect device to access again
             client.close()

src/cryptoadvance/specter/static/hwi.js

@@ -121,12 +121,13 @@ class HWIBridge {
         });
     }
 
-    async getXpubs(device, passphrase=""){
+    async getXpubs(device, account=0, passphrase=""){
         if(!('passphrase' in device)){
             device.passphrase = passphrase;
         }
         return await this.fetch('extract_xpubs', {
             device_type: device.type,
+            account: account,
             path: device.path,
             passphrase: device.passphrase,
         });

src/cryptoadvance/specter/templates/device/new_device.jinja

@@ -74,7 +74,14 @@
 						<img src="/static/img/usb_tiny.svg" height="12px">Get over USB
 					</button>
 				</div>
-				<br>
+				<p class="note center" style="text-decoration: underline; cursor: pointer;" onclick="showPageOverlay('usb_import_account_number')">Specify account number (advanced)</p>
+				<div class="hidden" id="usb_import_account_number">
+					<h1>Select the acount you wish to import</h1>
+					<p class="center" style="max-width: 500px; margin: 5px auto;">You can set here which account number you wish to import.<br>Account derivation uses the number choosen here to derive an xpub as specified in <a style="color: #fff" href="https://github.com/bitcoin/bips/blob/master/bip-0044.mediawiki#account" target="_blank">BIP44</a>.</p>
+					Account # <input type="number" step="1" min="0" value="0" id="usb_account_number" style="max-width: 100px; min-width: 100px;"><br><br>
+					<p class="note center">This is an advanced feature.<br>If you're not familiar with account derivations please leave this as 0.</p><br>
+					<button class="btn centered" type="button" onclick="hidePageOverlay()">Close</button>
+				</div>
 				<div class="note">
 					Examples:<br>
 			<pre style="font-size: 1em">
@@ -222,13 +229,13 @@ upub5En4f7k8gaG2KDHvBeEYox...rFpJRHpiZ4DE
 <script type="text/javascript">
 	{% include "device/components/add_keys.js" %}
 
-	async function getXpubs(device, passphrase=""){
+	async function getXpubs(device, account=0, passphrase=""){
 		// detect device
         showHWIProgress("Extracting public keys...", 
         	`It may take a while.<br><br>Keep your ${capitalize(device.type)} connected.`);
 		let result = [];
 		try {
-			result = await hwi.getXpubs(device, passphrase);
+			result = await hwi.getXpubs(device, account, passphrase);
 		} catch (error) {
 			handleHWIError(error);
 			return null;
@@ -261,7 +268,9 @@ upub5En4f7k8gaG2KDHvBeEYox...rFpJRHpiZ4DE
 		if(device == null){
 			return;
 		}
-		let xpubs = await getXpubs(device);
+		
+		let account = document.getElementById('usb_account_number').value;
+		let xpubs = await getXpubs(device, account);
 		if(xpubs == null){
 			return;
 		}