Also support derivation paths of length 3.

Author: murisi

app/src/addr.c

@@ -55,7 +55,7 @@ zxerr_t addr_getItem(int8_t displayIdx,
 
             snprintf(outKey, outKeyLen, "Your Path");
             char buffer[300];
-            bip32_to_str(buffer, sizeof(buffer), hdPath, HDPATH_LEN_DEFAULT);
+            bip32_to_str(buffer, sizeof(buffer), hdPath, hdPathLen);
             pageString(outVal, outValLen, buffer, pageIdx, pageCount);
             return zxerr_ok;
         }

app/src/apdu_handler.c

@@ -39,14 +39,14 @@ __Z_INLINE void extractHDPath(uint32_t rx, uint32_t offset) {
     ZEMU_LOGF(50, "Extract HDPath\n")
     tx_initialized = false;
 
-    const uint8_t pathLength = G_io_apdu_buffer[offset];
+    hdPathLen = G_io_apdu_buffer[offset];
     offset++;
 
-    if (pathLength != HDPATH_LEN_DEFAULT || (rx - offset) != sizeof(uint32_t) * pathLength) {
+    if ((hdPathLen != HDPATH_LEN_DEFAULT && hdPathLen != IDENTITY_DER_PATH_LEN) || (rx - offset) != sizeof(uint32_t) * hdPathLen) {
         THROW(APDU_CODE_WRONG_LENGTH);
     }
 
-    memcpy(hdPath, G_io_apdu_buffer + offset, sizeof(uint32_t) * HDPATH_LEN_DEFAULT);
+    memcpy(hdPath, G_io_apdu_buffer + offset, sizeof(uint32_t) * hdPathLen);
 
     const bool mainnet = hdPath[0] == HDPATH_0_DEFAULT &&
                          hdPath[1] == HDPATH_1_DEFAULT;

app/src/coin.h

@@ -22,6 +22,7 @@ extern "C" {
 #define CLA                             0x57
 
 #define HDPATH_LEN_DEFAULT   5
+#define IDENTITY_DER_PATH_LEN 3
 #define HDPATH_0_DEFAULT     (0x80000000u | 0x2cu)   //44
 
 #define HDPATH_1_DEFAULT     (0x80000000u | 0x36d)  //877

app/src/crypto.c

@@ -70,7 +70,7 @@ static zxerr_t crypto_extractPublicKey_ed25519(uint8_t *pubKey, uint16_t pubKeyL
     CATCH_CXERROR(os_derive_bip32_with_seed_no_throw(HDW_ED25519_SLIP10,
                                                      CX_CURVE_Ed25519,
                                                      hdPath,
-                                                     HDPATH_LEN_DEFAULT,
+                                                     hdPathLen,
                                                      privateKeyData,
                                                      NULL,
                                                      NULL,
@@ -111,7 +111,7 @@ static zxerr_t crypto_sign_ed25519(uint8_t *output, uint16_t outputLen, const ui
     CATCH_CXERROR(os_derive_bip32_with_seed_no_throw(HDW_ED25519_SLIP10,
                                                      CX_CURVE_Ed25519,
                                                      hdPath,
-                                                     HDPATH_LEN_DEFAULT,
+                                                     hdPathLen,
                                                      privateKeyData,
                                                      NULL,
                                                      NULL,
@@ -550,7 +550,7 @@ zxerr_t crypto_computeSaplingSeed(uint8_t spendingKey[static KEY_LENGTH]) {
     CATCH_CXERROR(os_derive_bip32_with_seed_no_throw(HDW_NORMAL,
                                                      CX_CURVE_Ed25519,
                                                      hdPath,
-                                                     HDPATH_LEN_DEFAULT,
+                                                     hdPathLen,
                                                      privateKeyData,
                                                      NULL, NULL, 0));
     memcpy(spendingKey, privateKeyData, KEY_LENGTH);

app/src/crypto.h

@@ -27,6 +27,7 @@ extern "C" {
 #include "parser_txdef.h"
 
 extern uint32_t hdPath[HDPATH_LEN_DEFAULT];
+extern uint8_t hdPathLen;
 
 zxerr_t crypto_fillAddress(signing_key_type_e addressKind, uint8_t *buffer, uint16_t bufferLen, uint16_t *cmdResponseLen);
 zxerr_t crypto_sign(const parser_tx_t *txObj, uint8_t *output, uint16_t outputLen);

app/src/crypto_helper.c

@@ -52,6 +52,7 @@
 #include "blake2.h"
 
 uint32_t hdPath[HDPATH_LEN_DEFAULT];
+uint8_t hdPathLen;
 
 uint8_t bech32_hrp_len;
 char bech32_hrp[MAX_BECH32_HRP_LEN + 1];

app/src/review_keys.c

@@ -51,7 +51,7 @@ zxerr_t getItemPublicAddress(int8_t displayIdx, char *outKey, uint16_t outKeyLen
         case 1: {
             snprintf(outKey, outKeyLen, "HD Path");
             char buffer[200] = {0};
-            bip32_to_str(buffer, sizeof(buffer), hdPath, HDPATH_LEN_DEFAULT);
+            bip32_to_str(buffer, sizeof(buffer), hdPath, hdPathLen);
             pageString(outVal, outValLen, buffer, pageIdx, pageCount);
             break;
         }
@@ -90,7 +90,7 @@ zxerr_t getItemProofGenerationKey(int8_t displayIdx, char *outKey, uint16_t outK
         case 2: {
             snprintf(outKey, outKeyLen, "HD Path");
             char buffer[200] = {0};
-            bip32_to_str(buffer, sizeof(buffer), hdPath, HDPATH_LEN_DEFAULT);
+            bip32_to_str(buffer, sizeof(buffer), hdPath, hdPathLen);
             pageString(outVal, outValLen, buffer, pageIdx, pageCount);
             break;
         }
@@ -135,7 +135,7 @@ zxerr_t getItemViewKey(int8_t displayIdx, char *outKey, uint16_t outKeyLen, char
         case 3: {
             snprintf(outKey, outKeyLen, "HD Path");
             char buffer[200] = {0};
-            bip32_to_str(buffer, sizeof(buffer), hdPath, HDPATH_LEN_DEFAULT);
+            bip32_to_str(buffer, sizeof(buffer), hdPath, hdPathLen);
             pageString(outVal, outValLen, buffer, pageIdx, pageCount);
             break;
         }