Support for multipath descriptors

Cargo.toml

@@ -32,6 +32,7 @@ cln-plugin = { git = "https://github.com/elementsproject/lightning", version = "
 cln-rpc = "0.1.3"
 home = "0.5.5"
 log = "0.4.18"
+miniscript = "10.0.0"
 serde = "1.0.159"
 serde_json = "1.0.72"
 

src/wallet.rs

@@ -17,9 +17,11 @@ use bitcoincore_rpc::{
 };
 use clap::{command, Parser};
 use cln_plugin::{Error, Plugin};
+use miniscript::Descriptor;
 use serde::{Deserialize, Serialize};
 use serde_json::json;
 use std::{collections::BTreeMap, fmt, path::PathBuf, time::Duration};
+use std::str::FromStr;
 
 use crate::state::State;
 
@@ -120,9 +122,9 @@ fn find_closest_lower_key(map: &BTreeMap<u32, BlockHash>, key: u32) -> Option<(u
 #[derive(Debug, Deserialize, Serialize, Clone, Parser)]
 #[command(author, version, about, long_about = None)]
 pub struct AddArgs {
-    /// External descriptor of wallet to add
+    /// External or multipath descriptor of wallet to add
     pub descriptor: String,
-    /// Internal descriptor of wallet to add
+    /// Optional internal descriptor of wallet to add
     pub change_descriptor: Option<String>,
     /// Birthday of wallet to add. Must be a block height between 0 and 4294967295
     pub birthday: Option<u32>,
@@ -167,9 +169,19 @@ impl DescriptorWallet {
     }
 
     pub fn from_args(args: AddArgs, network: String) -> Result<Self, WatchError> {
+        let mut descriptor = args.descriptor;
+        let mut change_descriptor = args.change_descriptor;
+        let descriptor_obj = Descriptor::from_str(&descriptor).unwrap();
+
+        if descriptor_obj.is_multipath() {
+            let descriptor_vec = descriptor_obj.clone().into_single_descriptors().unwrap();
+            descriptor = descriptor_vec[0].to_string();
+            change_descriptor = Some(descriptor_vec[1].to_string());
+        }
+
         Ok(Self {
-            descriptor: args.descriptor,
-            change_descriptor: args.change_descriptor,
+            descriptor: descriptor,
+            change_descriptor: change_descriptor,
             birthday: args.birthday,
             gap: args.gap,
             transactions: BTreeMap::new(),

tests/test_rpc_add_bip389.py

@@ -0,0 +1,132 @@
+def test_rpc_add_with_bip389_descriptor(bitcoind, ln_node):
+    """
+    Test RPC add.
+    """
+
+    multipath_descriptor = "wpkh([b36d6b75/84'/1'/0']tpubDCkkbWNApTd7UqKxCL44mSYgMP3Km72kXunMtX9LLvJvvbtmgEncaW4LJFeeVBy5pBpo2aKVqZc9ZbCGnzHKS3zhxBUSfhLNxL2cKnnY5HB/<0;1>/*)"  # noqa: E501
+    # expanded_descriptor_0 = "wpkh([dc182901/84'/1'/0']tpubDCkvbN1aD7W4na5MLZR7pwEn4e6XzNFLfKAfDTyvrQ83Y9WeSWL21xYmUSwaqBa3PaojNBztKiTrYWPRApuux5ZXitvc1wsmYuFFThBX12W/0/*)"  # noqa: E501
+    # expanded_descriptor_1 = "wpkh([dc182901/84'/1'/0']tpubDCkvbN1aD7W4na5MLZR7pwEn4e6XzNFLfKAfDTyvrQ83Y9WeSWL21xYmUSwaqBa3PaojNBztKiTrYWPRApuux5ZXitvc1wsmYuFFThBX12W/1/*)"  # noqa: E501
+
+    smaug_wallets = ln_node.rpc.smaug("ls")
+    assert len(smaug_wallets) == 0
+
+    # Add a wallet to smaug
+    wallet = ln_node.rpc.smaug(
+        # "add", expanded_descriptor_0, expanded_descriptor_1, "821000", "5000"
+        "add",
+        multipath_descriptor,
+        "",
+        "821000",
+        "5000",  # TODO: None
+    )
+    wallet_name = wallet["name"]
+
+    asserted = {
+        "message": f"Wallet with deterministic name {wallet_name} "
+        "successfully added",
+        "name": wallet_name,
+    }
+
+    assert len(wallet.keys()) == len(asserted.keys())
+    for key, value in wallet.items():
+        assert value == asserted[key]
+
+    smaug_wallets = ln_node.rpc.smaug("ls")
+    assert len(smaug_wallets) == 1
+
+    ln_node.daemon.wait_for_log(
+        f"Wallet with deterministic name {wallet_name} successfully added"
+    )
+
+
+def test_checksum():
+    d = "wpkh([dc182901/84'/1'/0']tpubDCkvbN1aD7W4na5MLZR7pwEn4e6XzNFLfKAfDTyvrQ83Y9WeSWL21xYmUSwaqBa3PaojNBztKiTrYWPRApuux5ZXitvc1wsmYuFFThBX12W/<0;1>/*)"  # noqa: E501
+    assert (descsum_create(d)) == d + "#x0j07q3h"
+
+
+# Below copied from https://github.com/bitcoin/bitcoin/blob/5fbcc8f0560cce36abafb8467339276b7c0d62b6/test/functional/test_framework/descriptors.py  # noqa: E501
+
+# !/usr/bin/env python3
+# Copyright (c) 2019 Pieter Wuille
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+"""Utility functions related to output descriptors"""
+
+import re  # noqa: E402
+
+INPUT_CHARSET = "0123456789()[],'/*abcdefgh@:$%{}IJKLMNOPQRSTUVWXYZ&+-.;<=>?!^_|~ijklmnopqrstuvwxyzABCDEFGH`#\"\\ "  # noqa: E501
+CHECKSUM_CHARSET = "qpzry9x8gf2tvdw0s3jn54khce6mua7l"
+GENERATOR = [
+    0xF5DEE51989,
+    0xA9FDCA3312,
+    0x1BAB10E32D,
+    0x3706B1677A,
+    0x644D626FFD,
+]
+
+
+def descsum_polymod(symbols):
+    """Internal function that computes the descriptor checksum."""
+    chk = 1
+    for value in symbols:
+        top = chk >> 35
+        chk = (chk & 0x7FFFFFFFF) << 5 ^ value
+        for i in range(5):
+            chk ^= GENERATOR[i] if ((top >> i) & 1) else 0
+    return chk
+
+
+def descsum_expand(s):
+    """Internal function that does the character to symbol expansion"""  # noqa: E501
+    groups = []
+    symbols = []
+    for c in s:
+        if not c in INPUT_CHARSET:  # noqa: E713
+            return None
+        v = INPUT_CHARSET.find(c)
+        symbols.append(v & 31)
+        groups.append(v >> 5)
+        if len(groups) == 3:
+            symbols.append(groups[0] * 9 + groups[1] * 3 + groups[2])
+            groups = []
+    if len(groups) == 1:
+        symbols.append(groups[0])
+    elif len(groups) == 2:
+        symbols.append(groups[0] * 3 + groups[1])
+    return symbols
+
+
+def descsum_create(s):
+    """Add a checksum to a descriptor without"""
+    symbols = descsum_expand(s) + [0, 0, 0, 0, 0, 0, 0, 0]
+    checksum = descsum_polymod(symbols) ^ 1
+    return (
+        s
+        + "#"
+        + "".join(
+            CHECKSUM_CHARSET[(checksum >> (5 * (7 - i))) & 31]
+            for i in range(8)
+        )
+    )
+
+
+def descsum_check(s, require=True):
+    """Verify that the checksum is correct in a descriptor"""
+    if not "#" in s:  # noqa: E713
+        return not require
+    if s[-9] != "#":
+        return False
+    if not all(x in CHECKSUM_CHARSET for x in s[-8:]):
+        return False
+    symbols = descsum_expand(s[:-9]) + [
+        CHECKSUM_CHARSET.find(x) for x in s[-8:]
+    ]
+    return descsum_polymod(symbols) == 1
+
+
+def drop_origins(s):
+    """Drop the key origins from a descriptor"""
+    desc = re.sub(r"\[.+?\]", "", s)
+    if "#" in s:
+        desc = desc[: desc.index("#")]
+    return descsum_create(desc)