Factorize getEthPublicKey to be used in other modules

Author: cedelavergne-ledger

Makefile

@@ -268,6 +268,7 @@ endif
 
 # Allow usage of function from lib_standard_app/crypto_helpers.c
 APP_SOURCE_FILES += ${BOLOS_SDK}/lib_standard_app/crypto_helpers.c
+INCLUDES_PATH += ${BOLOS_SDK}/lib_standard_app
 
 ### initialize plugin SDK submodule if needed, rebuild it, and warn if a difference is noticed
 ifeq ($(CHAIN),ethereum)

src/apdu_constants.h

@@ -112,6 +112,8 @@ void handlePerformPrivacyOperation(uint8_t p1,
                                    unsigned int *flags,
                                    unsigned int *tx);
 
+void getEthPublicKey(uint32_t *bip32Path, uint8_t bip32PathLength);
+
 #ifdef HAVE_ETH2
 
 void handleGetEth2PublicKey(uint8_t p1,

src_features/getPublicKey/cmd_getPublicKey.c

@@ -4,16 +4,36 @@
 #include "feature_getPublicKey.h"
 #include "common_ui.h"
 #include "os_io_seproxyhal.h"
+#include "crypto_helpers.h"
+
+void getEthPublicKey(uint32_t *bip32Path, uint8_t bip32PathLength) {
+    tmpCtx.publicKeyContext.publicKey.curve = CX_CURVE_256K1;
+    tmpCtx.publicKeyContext.publicKey.W_len = 65;
+    if (bip32_derive_get_pubkey_256(
+            CX_CURVE_256K1,
+            bip32Path,
+            bip32PathLength,
+            tmpCtx.publicKeyContext.publicKey.W,
+            (tmpCtx.publicKeyContext.getChaincode ? tmpCtx.publicKeyContext.chainCode : NULL),
+            CX_SHA512) != CX_OK) {
+        THROW(CX_INVALID_PARAMETER);
+    }
+
+    if (!getEthAddressStringFromKey(&tmpCtx.publicKeyContext.publicKey,
+                                    tmpCtx.publicKeyContext.address,
+                                    &global_sha3,
+                                    chainConfig->chainId)) {
+        THROW(CX_INVALID_PARAMETER);
+    }
+}
 
 void handleGetPublicKey(uint8_t p1,
                         uint8_t p2,
                         const uint8_t *dataBuffer,
                         uint8_t dataLength,
                         unsigned int *flags,
                         unsigned int *tx) {
-    uint8_t privateKeyData[INT256_LENGTH];
     bip32_path_t bip32;
-    cx_ecfp_private_key_t privateKey;
 
     if (!G_called_from_swap) {
         reset_app_context();
@@ -35,25 +55,7 @@ void handleGetPublicKey(uint8_t p1,
     }
 
     tmpCtx.publicKeyContext.getChaincode = (p2 == P2_CHAINCODE);
-    io_seproxyhal_io_heartbeat();
-    os_perso_derive_node_bip32(
-        CX_CURVE_256K1,
-        bip32.path,
-        bip32.length,
-        privateKeyData,
-        (tmpCtx.publicKeyContext.getChaincode ? tmpCtx.publicKeyContext.chainCode : NULL));
-    cx_ecfp_init_private_key(CX_CURVE_256K1, privateKeyData, 32, &privateKey);
-    io_seproxyhal_io_heartbeat();
-    cx_ecfp_generate_pair(CX_CURVE_256K1, &tmpCtx.publicKeyContext.publicKey, &privateKey, 1);
-    explicit_bzero(&privateKey, sizeof(privateKey));
-    explicit_bzero(privateKeyData, sizeof(privateKeyData));
-    io_seproxyhal_io_heartbeat();
-    if (!getEthAddressStringFromKey(&tmpCtx.publicKeyContext.publicKey,
-                                    tmpCtx.publicKeyContext.address,
-                                    &global_sha3,
-                                    chainConfig->chainId)) {
-        THROW(CX_INVALID_PARAMETER);
-    }
+    getEthPublicKey(bip32.path, bip32.length);
 
     uint64_t chain_id = chainConfig->chainId;
     if (dataLength >= sizeof(chain_id)) {