[Bitcoin]: Add support for Taproot address generation (#4074)

* [Bitcoin]: Add taproot derivation

* Refactor codegen tool to generate newly added derivations
* Add `TWDerivation.h` to the git index

* [Bitcoin]: Generate Rust enum variants as well

* [Bitcoin]: Handle `TWDerivationBitcoinTaproot` enum variant

* Add missing `file_editor.rb` file

* [Bitcoin]: Forward deriveAddress to Rust if derivation is Taproot

* [Bitcoin]: Add Android tests

* [Bitcoin]: Add taproot derivation iOS tests

Author: satoshiotomakan

.gitignore

@@ -38,7 +38,6 @@ codegen-v2/bindings/
 src/Generated/*.cpp
 include/TrustWalletCore/TWHRP.h
 include/TrustWalletCore/TW*Proto.h
-include/TrustWalletCore/TWDerivation.h
 include/TrustWalletCore/TWEthereumChainID.h
 
 # Wasm

android/app/src/androidTest/java/com/trustwallet/core/app/blockchains/TestCoinType.kt

@@ -54,6 +54,8 @@ class TestCoinType {
         assertEquals(res, "m/84'/0'/0'/0/0")
         res = CoinType.createFromValue(CoinType.BITCOIN.value()).derivationPathWithDerivation(Derivation.BITCOINLEGACY).toString()
         assertEquals(res, "m/44'/0'/0'/0/0")
+        res = CoinType.createFromValue(CoinType.BITCOIN.value()).derivationPathWithDerivation(Derivation.BITCOINTAPROOT).toString()
+        assertEquals(res, "m/86'/0'/0'/0/0")
         res = CoinType.createFromValue(CoinType.SOLANA.value()).derivationPathWithDerivation(Derivation.SOLANASOLANA).toString()
         assertEquals(res, "m/44'/501'/0'/0'")
     }

android/app/src/androidTest/java/com/trustwallet/core/app/utils/TestAnyAddress.kt

@@ -58,6 +58,9 @@ class TestAnyAddress {
 
         val address2 = AnyAddress(pubkey, coin, Derivation.BITCOINLEGACY)
         assertEquals(address2.description(), "1JvRfEQFv5q5qy9uTSAezH7kVQf4hqnHXx")
+
+        val address3 = AnyAddress(pubkey, coin, Derivation.BITCOINTAPROOT)
+        assertEquals(address3.description(), "bc1pnncpg8s7gu7t6xmmzxqarcj8ydthmaz8gr4m76eephjfprs53maswgel0w")
     }
 
     @Test

android/app/src/androidTest/java/com/trustwallet/core/app/utils/TestHDWallet.kt

@@ -121,6 +121,9 @@ class TestHDWallet {
 
         val key3 = wallet.getKeyDerivation(coin, Derivation.BITCOINTESTNET)
         assertEquals(key3.data().toHex(), "0xca5845e1b43e3adf577b7f110b60596479425695005a594c88f9901c3afe864f")
+
+        val key4 = wallet.getKeyDerivation(coin, Derivation.BITCOINTAPROOT)
+        assertEquals(key4.data().toHex(), "0xa2c4d6df786f118f20330affd65d248ffdc0750ae9cbc729d27c640302afd030")
     }
 
     @Test
@@ -145,6 +148,9 @@ class TestHDWallet {
 
         val address3 = wallet.getAddressDerivation(coin, Derivation.BITCOINTESTNET)
         assertEquals(address3, "tb1qwgpxgwn33z3ke9s7q65l976pseh4edrzfmyvl0")
+
+        val address4 = wallet.getAddressDerivation(coin, Derivation.BITCOINTAPROOT)
+        assertEquals(address4, "bc1pgqks0cynn93ymve4x0jq3u7hne77908nlysp289hc44yc4cmy0hslyckrz")
     }
 
     @Test

codegen/bin/coins

@@ -4,6 +4,10 @@ require 'erb'
 require 'fileutils'
 require 'json'
 
+CurrentDir = File.dirname(__FILE__)
+$LOAD_PATH.unshift(File.join(CurrentDir, '..', 'lib'))
+require 'derivation'
+
 # Transforms a coin name to a C++ name
 def self.format_name(n)
   formatted = n
@@ -18,24 +22,10 @@ def self.coin_name(coin)
   coin['displayName'] || coin['name']
 end
 
-def self.derivation_path(coin)
-  coin['derivation'][0]['path']
-end
-
 def self.camel_case(id)
   id[0].upcase + id[1..].downcase
 end
 
-def self.derivation_name(deriv)
-  return "" if deriv['name'].nil?
-  deriv['name'].downcase
-end
-
-def self.derivation_enum_name(deriv, coin)
-  return "TWDerivationDefault" if deriv['name'].nil?
-  "TWDerivation" + format_name(coin['name']) + camel_case(deriv['name'])
-end
-
 def self.coin_img(coin)
   "<img src=\"https://raw.githubusercontent.com/trustwallet/assets/master/blockchains/#{coin}/info/logo.png\" width=\"32\" />"
 end
@@ -55,14 +45,16 @@ coins = JSON.parse(json_string).sort_by { |x| x['coinId'] }
 enum_count = 0
 
 erbs = [
-  {'template' => 'TWDerivation.h.erb', 'folder' => 'include/TrustWalletCore', 'file' => 'TWDerivation.h'},
   {'template' => 'CoinInfoData.cpp.erb', 'folder' => 'src/Generated', 'file' => 'CoinInfoData.cpp'},
   {'template' => 'registry.md.erb', 'folder' => 'docs', 'file' => 'registry.md'},
   {'template' => 'hrp.cpp.erb', 'folder' => 'src/Generated', 'file' => 'TWHRP.cpp'},
   {'template' => 'hrp.h.erb', 'folder' => 'include/TrustWalletCore', 'file' => 'TWHRP.h'},
   {'template' => 'TWEthereumChainID.h.erb', 'folder' => 'include/TrustWalletCore', 'file' => 'TWEthereumChainID.h'}
 ]
 
+# Update coins derivations if changed.
+update_derivation_enum(coins)
+
 FileUtils.mkdir_p File.join('src', 'Generated')
 erbs.each do |erb|
   path = File.expand_path(erb['template'], File.join(File.dirname(__FILE__), '..', 'lib', 'templates'))

codegen/lib/coin_skeleton_gen.rb

@@ -7,6 +7,7 @@
 require 'entity_decl'
 require 'code_generator'
 require 'coin_test_gen'
+require 'file_editor'
 
 # Coin template generation
 
@@ -70,26 +71,6 @@ def insert_coin_entry(coin)
     insert_target_line(target_file, target_line, "        // end_of_coin_dipatcher_switch_marker_do_not_modify\n")
 end
 
-def self.insert_target_line(target_file, target_line, original_line)
-    lines = File.readlines(target_file)
-    index = lines.index(target_line)
-    if !index.nil?
-        puts "Line is already present, file: #{target_file}  line: #{target_line}"
-        return true
-    end
-    index = lines.index(original_line)
-    if index.nil?
-        puts "WARNING: Could not find line! file: #{target_file}  line: #{original_line}"
-        return false
-    end
-    lines.insert(index, target_line)
-    File.open(target_file, "w+") do |f|
-        f.puts(lines)
-    end
-    puts "Updated file: #{target_file}  new line: #{target_line}"
-    return true
-end
-
 def generate_blockchain_files(coin)
     name = format_name(coin)
 

codegen/lib/derivation.rb

@@ -0,0 +1,76 @@
+# frozen_string_literal: true
+
+require 'file_editor'
+
+$derivation_file = "include/TrustWalletCore/TWDerivation.h"
+$derivation_file_rust = "rust/tw_coin_registry/src/tw_derivation.rs"
+
+# Returns a derivation name if specified.
+def derivation_name(deriv)
+  return "" if deriv['name'].nil?
+  deriv['name'].downcase
+end
+
+# Returns a string of `<Coin><Derivation>` if derivation's name is specified, otherwise returns `Default`.
+def derivation_enum_name_no_prefix(deriv, coin)
+  return "Default" if deriv['name'].nil?
+  format_name(coin['name']) + camel_case(deriv['name'])
+end
+
+# Returns a string of `TWDerivation<Coin><Derivation>` if derivation's name is specified, otherwise returns `TWDerivationDefault`.
+def derivation_enum_name(deriv, coin)
+  return "TWDerivation" + derivation_enum_name_no_prefix(deriv, coin)
+end
+
+# Returns a derivation path.
+def derivation_path(coin)
+  coin['derivation'][0]['path']
+end
+
+# Get the last `TWDerivation` enum variant ID.
+def get_last_derivation(file_path)
+  last_derivation_id = nil
+
+  File.open(file_path, "r") do |file|
+    file.each_line do |line|
+      # Match lines that define a TWDerivation enum value
+      if line =~ /TWDerivation\w+\s*=\s*(\d+),/
+        last_derivation_id = $1.to_i
+      end
+    end
+  end
+
+  last_derivation_id
+end
+
+# Returns whether the TWDerivation enum contains the given `derivation` variant.
+def find_derivation(file_path, derivation)
+  File.open(file_path, "r") do |file|
+    file.each_line do |line|
+      return true if line.include?(derivation)
+    end
+  end
+  return false
+end
+
+# Insert a new `TWDerivation<X> = N,` to the end of the enum.
+def insert_derivation(file_path, derivation, derivation_id)
+  target_line = "    #{derivation} = #{derivation_id},"
+  insert_target_line(file_path, target_line, "    // end_of_derivation_enum - USED TO GENERATE CODE\n")
+end
+
+# Update TWDerivation enum variants if new derivation appeared.
+def update_derivation_enum(coins)
+  coins.each do |coin|
+    coin['derivation'].each_with_index do |deriv, index|
+      deriv_name = derivation_enum_name(deriv, coin)
+      if !find_derivation($derivation_file, deriv_name)
+        new_derivation_id = get_last_derivation($derivation_file) + 1
+        insert_derivation($derivation_file, deriv_name, new_derivation_id)
+
+        rust_deriv_name = derivation_enum_name_no_prefix(deriv, coin)
+        insert_derivation($derivation_file_rust, rust_deriv_name, new_derivation_id)
+      end
+    end
+  end
+end

codegen/lib/file_editor.rb

@@ -0,0 +1,19 @@
+def insert_target_line(target_file, target_line, original_line)
+  lines = File.readlines(target_file)
+  index = lines.index(target_line)
+  if !index.nil?
+      puts "Line is already present, file: #{target_file}  line: #{target_line}"
+      return true
+  end
+  index = lines.index(original_line)
+  if index.nil?
+      puts "WARNING: Could not find line! file: #{target_file}  line: #{original_line}"
+      return false
+  end
+  lines.insert(index, target_line)
+  File.open(target_file, "w+") do |f|
+      f.puts(lines)
+  end
+  puts "Updated file: #{target_file}  new line: #{target_line}"
+  return true
+end

include/TrustWalletCore/TWDerivation.h

@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: Apache-2.0
+//
+// Copyright © 2017 Trust Wallet.
+//
+// This is a GENERATED FILE from \registry.json, changes made here WILL BE LOST.
+//
+
+#pragma once
+
+#include "TWBase.h"
+
+TW_EXTERN_C_BEGIN
+
+/// Non-default coin address derivation names (default, unnamed derivations are not included).
+/// Note the enum variant must be sync with `TWDerivation` enum in Rust:
+/// https://github.com/trustwallet/wallet-core/blob/master/rust/tw_coin_registry/src/tw_derivation.rs
+TW_EXPORT_ENUM()
+enum TWDerivation {
+    TWDerivationDefault = 0, // default, for any coin
+    TWDerivationCustom = 1, // custom, for any coin
+    TWDerivationBitcoinSegwit = 2,
+    TWDerivationBitcoinLegacy = 3,
+    TWDerivationBitcoinTestnet = 4,
+    TWDerivationLitecoinLegacy = 5,
+    TWDerivationSolanaSolana = 6,
+    TWDerivationStratisSegwit = 7,
+    TWDerivationBitcoinTaproot = 8,
+    // end_of_derivation_enum - USED TO GENERATE CODE
+};
+
+TW_EXTERN_C_END

include/TrustWalletCore/TWPurpose.h

@@ -18,6 +18,7 @@ enum TWPurpose {
     TWPurposeBIP44 = 44,
     TWPurposeBIP49 = 49, // Derivation scheme for P2WPKH-nested-in-P2SH
     TWPurposeBIP84 = 84, // Derivation scheme for P2WPKH
+    TWPurposeBIP86 = 86, // Derivation scheme for P2TR
     TWPurposeBIP1852 = 1852, // Derivation scheme used by Cardano-Shelley
 };
 

registry.json

@@ -24,6 +24,12 @@
         "path": "m/84'/1'/0'/0/0",
         "xpub": "zpub",
         "xprv": "zprv"
+      },
+      {
+        "name": "taproot",
+        "path": "m/86'/0'/0'/0/0",
+        "xpub": "zpub",
+        "xprv": "zprv"
       }
     ],
     "curve": "secp256k1",

rust/frameworks/tw_utxo/src/address/derivation.rs

@@ -6,10 +6,12 @@ use tw_coin_entry::coin_context::CoinContext;
 use tw_coin_entry::derivation::{ChildIndex, Derivation};
 
 pub const SEGWIT_DERIVATION_PATH_TYPE: ChildIndex = ChildIndex::Hardened(84);
+pub const TAPROOT_DERIVATION_PATH_TYPE: ChildIndex = ChildIndex::Hardened(86);
 
 pub enum BitcoinDerivation {
     Legacy,
     Segwit,
+    Taproot,
 }
 
 impl BitcoinDerivation {
@@ -23,6 +25,7 @@ impl BitcoinDerivation {
             Derivation::Default | Derivation::Testnet => (),
             Derivation::Segwit => return BitcoinDerivation::Segwit,
             Derivation::Legacy => return BitcoinDerivation::Legacy,
+            Derivation::Taproot => return BitcoinDerivation::Taproot,
         }
 
         let Some(default_derivation) = coin.derivations().first() else {
@@ -32,9 +35,13 @@ impl BitcoinDerivation {
 
         match default_derivation.name {
             Derivation::Segwit => BitcoinDerivation::Segwit,
+            Derivation::Taproot => BitcoinDerivation::Taproot,
             Derivation::Default if derivation_path_type == Some(SEGWIT_DERIVATION_PATH_TYPE) => {
                 BitcoinDerivation::Segwit
             },
+            Derivation::Default if derivation_path_type == Some(TAPROOT_DERIVATION_PATH_TYPE) => {
+                BitcoinDerivation::Taproot
+            },
             Derivation::Default | Derivation::Legacy | Derivation::Testnet => {
                 BitcoinDerivation::Legacy
             },
@@ -49,4 +56,11 @@ impl BitcoinDerivation {
                 || der.path.path().first().copied() == Some(SEGWIT_DERIVATION_PATH_TYPE)
         })
     }
+
+    pub fn tw_supports_taproot(coin: &dyn CoinContext) -> bool {
+        coin.derivations().iter().any(|der| {
+            der.name == Derivation::Taproot
+                || der.path.path().first().copied() == Some(TAPROOT_DERIVATION_PATH_TYPE)
+        })
+    }
 }

rust/frameworks/tw_utxo/src/address/standard_bitcoin.rs

@@ -82,8 +82,10 @@ impl StandardBitcoinAddress {
             if let Ok(segwit) = SegwitAddress::from_str_with_coin_and_prefix(coin, s, None) {
                 return Ok(StandardBitcoinAddress::Segwit(segwit));
             }
+        }
 
-            // TODO use `BitcoinDerivation::tw_supports_taproot` based on `registry.json`.
+        // Try to parse a Taproot address if the coin supports it.
+        if BitcoinDerivation::tw_supports_taproot(coin) {
             if let Ok(taproot) = TaprootAddress::from_str_with_coin_and_prefix(coin, s, None) {
                 return Ok(StandardBitcoinAddress::Taproot(taproot));
             }
@@ -127,6 +129,11 @@ impl StandardBitcoinAddress {
                 SegwitAddress::p2wpkh_with_coin_and_prefix(coin, public_key, None)
                     .map(StandardBitcoinAddress::Segwit)
             },
+            BitcoinDerivation::Taproot => {
+                let no_merkle_root = None;
+                TaprootAddress::p2tr_with_coin_and_prefix(coin, public_key, None, no_merkle_root)
+                    .map(StandardBitcoinAddress::Taproot)
+            },
         }
     }
 }

rust/tw_any_coin/src/test_utils/address_utils.rs

@@ -30,6 +30,15 @@ impl WithDestructor for TWAnyAddress {
 }
 
 pub fn test_address_derive(coin: CoinType, private_key: &str, address: &str) {
+    test_address_derive_with_derivation(coin, private_key, address, TWDerivation::Default)
+}
+
+pub fn test_address_derive_with_derivation(
+    coin: CoinType,
+    private_key: &str,
+    address: &str,
+    derivation: TWDerivation,
+) {
     let coin_item = get_coin_item(coin).unwrap();
 
     let private_key = TWPrivateKeyHelper::with_hex(private_key);
@@ -41,7 +50,7 @@ pub fn test_address_derive(coin: CoinType, private_key: &str, address: &str) {
         tw_any_address_create_with_public_key_derivation(
             public_key.ptr(),
             coin as u32,
-            TWDerivation::Default as u32,
+            derivation as u32,
         )
     });
 

rust/tw_coin_entry/src/derivation.rs

@@ -23,6 +23,7 @@ pub enum Derivation {
     Segwit,
     Legacy,
     Testnet,
+    Taproot,
     /// Default derivation.
     #[default]
     #[serde(other)]