Delay EIP-712 array traversal until size is received

src_features/signMessageEIP712/field_hash.c

@@ -228,7 +228,7 @@ static bool field_hash_finalize(const void *const field_ptr,
             return false;
         }
     }
-    path_advance();
+    path_advance(true);
     fh->state = FHS_IDLE;
     ui_712_finalize_field();
     return true;

src_features/signMessageEIP712/path.c

@@ -285,11 +285,14 @@ static bool array_depth_list_pop(void) {
  * Updates the path so that it doesn't point to a struct-type field, but rather
  * only to actual fields.
  *
+ * @param[in] skip_if_array skip if path is already pointing at an array
+ * @param[in] stop_at_array stop at the first downstream array
  * @return whether the path update worked or not
  */
-static bool path_update(void) {
+static bool path_update(bool skip_if_array, bool stop_at_array) {
     uint8_t fields_count;
     const void *struct_ptr;
+    const void *starting_field_ptr;
     const void *field_ptr;
     const char *typename;
     uint8_t typename_len;
@@ -298,10 +301,17 @@ static bool path_update(void) {
     if (path_struct == NULL) {
         return false;
     }
-    if ((field_ptr = get_field(NULL)) == NULL) {
+    if ((starting_field_ptr = get_field(NULL)) == NULL) {
         return false;
     }
+    field_ptr = starting_field_ptr;
     while (struct_field_type(field_ptr) == TYPE_CUSTOM) {
+        if (((field_ptr == starting_field_ptr) && skip_if_array) ||
+            ((field_ptr != starting_field_ptr) && stop_at_array)) {
+            if (struct_field_is_array(field_ptr)) {
+                break;
+            }
+        }
         typename = get_struct_field_typename(field_ptr, &typename_len);
         if ((struct_ptr = get_structn(typename, typename_len)) == NULL) {
             return false;
@@ -381,7 +391,7 @@ bool path_set_root(const char *const struct_name, uint8_t name_length) {
     struct_state = DEFINED;
 
     // because the first field could be a struct type
-    path_update();
+    path_update(true, true);
     return true;
 }
 
@@ -449,6 +459,9 @@ bool path_new_array_depth(const uint8_t *const data, uint8_t length) {
     }
 
     array_size = *data;
+    if (!path_update(false, array_size > 0)) {
+        return false;
+    }
     array_depth_count_bak = path_struct->array_depth_count;
     for (pidx = 0; pidx < path_struct->depth_count; ++pidx) {
         if ((field_ptr = get_nth_field(NULL, pidx + 1)) == NULL) {
@@ -492,7 +505,7 @@ bool path_new_array_depth(const uint8_t *const data, uint8_t length) {
     }
     if (array_size == 0) {
         do {
-            path_advance();
+            path_advance(false);
         } while (path_struct->array_depth_count != array_depth_count_bak);
     }
 
@@ -563,7 +576,7 @@ static bool path_advance_in_array(void) {
  *
  * @return whether the advancement was successful or not
  */
-bool path_advance(void) {
+bool path_advance(bool array_check) {
     bool end_reached;
 
     do {
@@ -573,8 +586,7 @@ bool path_advance(void) {
             end_reached = false;
         }
     } while (end_reached);
-    path_update();
-    return true;
+    return path_update(array_check, array_check);
 }
 
 /**

src_features/signMessageEIP712/path.h

@@ -27,7 +27,7 @@ typedef struct {
 
 bool path_set_root(const char *const struct_name, uint8_t length);
 const void *path_get_field(void);
-bool path_advance(void);
+bool path_advance(bool array_check);
 bool path_init(void);
 void path_deinit(void);
 bool path_new_array_depth(const uint8_t *const data, uint8_t length);