feat: coinjoin derivation path support (#63)

* feat: support coinjoin derivation paths

* chore: bump version to 0.38.1

* chore: bump up version 39.1

Author: pankcuf

Cargo.toml

@@ -3,7 +3,7 @@ members = ["dash", "hashes", "internals", "fuzz", "rpc-client", "rpc-json", "rpc
 resolver = "2"
 
 [workspace.package]
-version = "0.39.0"
+version = "0.39.1"
 
 [patch.crates-io.dashcore_hashes]
 path = "hashes"

dash/src/bip32.rs

@@ -36,12 +36,7 @@ use serde;
 
 use crate::base58;
 use crate::crypto::key::{self, Keypair, PrivateKey, PublicKey};
-use crate::dip9::{
-    DASH_BIP44_PATH_MAINNET, DASH_BIP44_PATH_TESTNET, IDENTITY_AUTHENTICATION_PATH_MAINNET,
-    IDENTITY_AUTHENTICATION_PATH_TESTNET, IDENTITY_INVITATION_PATH_MAINNET,
-    IDENTITY_INVITATION_PATH_TESTNET, IDENTITY_REGISTRATION_PATH_MAINNET,
-    IDENTITY_REGISTRATION_PATH_TESTNET, IDENTITY_TOPUP_PATH_MAINNET, IDENTITY_TOPUP_PATH_TESTNET,
-};
+use crate::dip9::{COINJOIN_PATH_MAINNET, COINJOIN_PATH_TESTNET, DASH_BIP44_PATH_MAINNET, DASH_BIP44_PATH_TESTNET, IDENTITY_AUTHENTICATION_PATH_MAINNET, IDENTITY_AUTHENTICATION_PATH_TESTNET, IDENTITY_INVITATION_PATH_MAINNET, IDENTITY_INVITATION_PATH_TESTNET, IDENTITY_REGISTRATION_PATH_MAINNET, IDENTITY_REGISTRATION_PATH_TESTNET, IDENTITY_TOPUP_PATH_MAINNET, IDENTITY_TOPUP_PATH_TESTNET};
 use crate::hash_types::XpubIdentifier;
 use crate::internal_macros::impl_bytes_newtype;
 use crate::io::Write;
@@ -494,6 +489,18 @@ impl DerivationPath {
         ]);
         root_derivation_path
     }
+    pub fn coinjoin_path(
+        network: Network,
+        account: u32,
+    ) -> Self {
+        let mut root_derivation_path: DerivationPath = match network {
+            Network::Dash => COINJOIN_PATH_MAINNET,
+            _ => COINJOIN_PATH_TESTNET,
+        }
+        .into();
+        root_derivation_path.0.extend(&[ChildNumber::Hardened { index: account }]);
+        root_derivation_path
+    }
 
     /// This might have been used in the past
     pub fn identity_registration_path_child_non_hardened(network: Network, index: u32) -> Self {
@@ -2059,6 +2066,15 @@ mod tests {
         assert_eq!(path.to_string(), "m/44'/1'/1'/0/42");
     }
 
+    #[test]
+    fn test_coinjoin_path() {
+        let path = DerivationPath::coinjoin_path(Network::Dash, 0);
+        assert_eq!(path.to_string(), "m/9'/5'/4'/0'");
+
+        let path = DerivationPath::coinjoin_path(Network::Testnet, 1);
+        assert_eq!(path.to_string(), "m/9'/1'/4'/1'");
+    }
+
     #[test]
     fn test_identity_registration_path() {
         let path = DerivationPath::identity_registration_path(Network::Dash, 10);

dash/src/dip9.rs

@@ -15,6 +15,7 @@ pub enum DerivationPathReference {
     BlockchainIdentityCreditTopupFunding = 12,
     BlockchainIdentityCreditInvitationFunding = 13,
     ProviderPlatformNodeKeys = 14,
+    CoinJoin = 15,
     Root = 255,
 }
 
@@ -118,6 +119,7 @@ pub const BIP44_PURPOSE: u32 = 44;
 pub const FEATURE_PURPOSE: u32 = 9;
 pub const DASH_COIN_TYPE: u32 = 5;
 pub const DASH_TESTNET_COIN_TYPE: u32 = 1;
+pub const FEATURE_PURPOSE_COINJOIN: u32 = 4;
 pub const FEATURE_PURPOSE_IDENTITIES: u32 = 5;
 pub const FEATURE_PURPOSE_IDENTITIES_SUBFEATURE_AUTHENTICATION: u32 = 0;
 pub const FEATURE_PURPOSE_IDENTITIES_SUBFEATURE_REGISTRATION: u32 = 1;
@@ -149,6 +151,26 @@ pub const DASH_BIP44_PATH_TESTNET: IndexConstPath<2> = IndexConstPath {
     reference: DerivationPathReference::BIP44,
     path_type: DerivationPathType::CLEAR_FUNDS,
 };
+// CoinJoin Paths
+
+pub const COINJOIN_PATH_MAINNET: IndexConstPath<3> = IndexConstPath {
+    indexes: [
+        ChildNumber::Hardened { index: FEATURE_PURPOSE },
+        ChildNumber::Hardened { index: DASH_COIN_TYPE },
+        ChildNumber::Hardened { index: FEATURE_PURPOSE_COINJOIN },
+    ],
+    reference: DerivationPathReference::CoinJoin,
+    path_type: DerivationPathType::ANONYMOUS_FUNDS,
+};
+pub const COINJOIN_PATH_TESTNET: IndexConstPath<3> = IndexConstPath {
+    indexes: [
+        ChildNumber::Hardened { index: FEATURE_PURPOSE },
+        ChildNumber::Hardened { index: DASH_TESTNET_COIN_TYPE },
+        ChildNumber::Hardened { index: FEATURE_PURPOSE_COINJOIN },
+    ],
+    reference: DerivationPathReference::CoinJoin,
+    path_type: DerivationPathType::ANONYMOUS_FUNDS,
+};
 
 pub const IDENTITY_REGISTRATION_PATH_MAINNET: IndexConstPath<4> = IndexConstPath {
     indexes: [