Address mismatch check

Author: may01

src/handlers/get_shielded_addr.rs

@@ -4,6 +4,8 @@ use zcash_address::unified::{Address as UnifiedAddress, Encoding, Receiver};
 use ledger_device_sdk::io::Comm;
 use ledger_device_sdk::log::{error, info};
 
+use crate::consts::UNHARDENED_MASK;
+
 use crate::app_ui::address::ui_display_shielded_address;
 use crate::utils::base58_address::{Base58Address, ToBase58Address};
 use crate::utils::bip32_path::Bip32Path;
@@ -64,6 +66,10 @@ pub fn handler_get_shielded_addr(
             error!("Transparent address path not BIP44 compliant");
             return Err(AppSW::IncorrectData);
         }
+        if (path.as_slice()[2] & UNHARDENED_MASK) != (transparent_path.as_slice()[2] & UNHARDENED_MASK) {
+            error!("Orchard and transparent address paths must have matching accounts");
+            return Err(AppSW::IncorrectData);
+        }
     }
 
     let orchard_fvk = derive_orchard_fvk(&path)?;

src/handlers/get_vk.rs

@@ -1,10 +1,11 @@
 use zcash_address::unified::{Encoding, Fvk, Ufvk};
 
 use alloc::format;
-use ledger_device_sdk::info;
+use ledger_device_sdk::log::{error, info};
 use ledger_device_sdk::io::Comm;
 
 use crate::app_ui::address::{ui_display_orchard_fvk, ui_display_ufvk};
+use crate::consts::{UNHARDENED_MASK, ZCASH_BIP44_COIN_TYPE};
 use crate::utils::{HexSlice, encode_string_response};
 use crate::zip32::{derive_orchard_fvk, derive_transparent_account_pubkey, orchard_network};
 use crate::{
@@ -15,6 +16,16 @@ use crate::{
 
 const VK_RESPONSE_CHUNK_LEN: usize = 255;
 
+fn check_transparent_vk_path(path: &Bip32Path) -> bool {
+    const HARDENED: u32 = 0x8000_0000;
+    const BIP44_PURPOSE: u32 = 44;
+    let p = path.as_slice();
+    p.len() == 3
+        && (p[0] & UNHARDENED_MASK) == BIP44_PURPOSE
+        && (p[1] & UNHARDENED_MASK) == ZCASH_BIP44_COIN_TYPE
+        && p[2] & HARDENED != 0
+}
+
 fn parse_vk_paths(data: &[u8], mode: P2VkMode) -> Result<(Bip32Path, Option<Bip32Path>), AppSW> {
     match mode {
         P2VkMode::OrchardFvk => Ok((Bip32Path::try_from(data)?, None)),
@@ -63,6 +74,19 @@ pub fn handler_get_vk(
     ctx.vk_response = None;
 
     let (path, transparent_path) = parse_vk_paths(data, mode)?;
+
+    if let P2VkMode::Ufvk = mode {
+        let t_path = transparent_path.as_ref().ok_or(AppSW::WrongApduLength)?;
+        if !check_transparent_vk_path(t_path) {
+            error!("Transparent VK path is not a valid account-level BIP44 path");
+            return Err(AppSW::IncorrectData);
+        }
+        if (path.as_slice()[2] & UNHARDENED_MASK) != (t_path.as_slice()[2] & UNHARDENED_MASK) {
+            error!("Orchard and transparent VK paths must have matching accounts");
+            return Err(AppSW::IncorrectData);
+        }
+    }
+
     let orchard_fvk = derive_orchard_fvk(&path)?;
 
     let response_bytes = match mode {

tests/standalone/test_pubkey_cmd.py

@@ -164,6 +164,20 @@ def test_get_ufvk_requires_transparent_path(backend):
     assert len(e.value.data) == 0
 
 
+def test_get_ufvk_account_mismatch(backend):
+    with pytest.raises(ExceptionRAPDU) as e:
+        backend.exchange(
+            cla=CLA,
+            ins=InsType.GET_VK,
+            p1=P1.P1_GET_VK_FIRST,
+            p2=GetVkMode.UFVK,
+            data=pack_derivation_path("m/32'/133'/0'") + pack_derivation_path("m/44'/133'/1'"),
+        )
+
+    assert e.value.status == Errors.SW_INVALID_TRANSACTION
+    assert len(e.value.data) == 0
+
+
 def test_get_orchard_fvk_confirm_accepted(backend, scenario_navigator):
     REF_ORCHARD_FVK_ACC_0 = bytes.fromhex(
         "e129bb7d06ed69a5ac01a664482ec9987fd19c40940bf76d98eb8b952974852949b0128d5072f9f92c7f7e8eb49a5434d2c04b67a30a55946d8322df3e484426f6151235e5897d34196943cb8f968312f1c8fba9ed82830b59f801b6de5da835"
@@ -301,3 +315,17 @@ def test_get_orchard_uaddress_requires_transparent_path(backend):
 
     assert e.value.status == Errors.SW_APP_WRONG_APDU_LENGTH
     assert len(e.value.data) == 0
+
+
+def test_get_orchard_uaddress_account_mismatch(backend):
+    with pytest.raises(ExceptionRAPDU) as e:
+        backend.exchange(
+            cla=CLA,
+            ins=InsType.GET_SHIELDED_ADDRESS,
+            p1=P1.P1_GET_PUBLIC_KEY_NO_DISPLAY,
+            p2=GetShieldedAddressMode.UADDRESS,
+            data=pack_derivation_path("m/32'/133'/0'") + pack_derivation_path("m/44'/133'/1'/0/0"),
+        )
+
+    assert e.value.status == Errors.SW_INVALID_TRANSACTION
+    assert len(e.value.data) == 0