diff --git a/tool/util.c b/tool/util.c
index b297aa1..af78260 100644
--- a/tool/util.c
+++ b/tool/util.c
@@ -91,10 +91,18 @@ unsigned char get_algorithm(EVP_PKEY *key) {
   }
 }
 
-X509_NAME *parse_name(char *name) {
+X509_NAME *parse_name(const char *orig_name) {
+  char name[1025];
   X509_NAME *parsed = NULL;
   char *ptr = name;
   char *part;
+
+  if(strlen(orig_name) > 1024) {
+    fprintf(stderr, "Name is to long!\n");
+    return NULL;
+  }
+  strcpy(name, orig_name);
+
   if(*name != '/') {
     fprintf(stderr, "Name does not start with '/'!\n");
     return NULL;
diff --git a/tool/util.h b/tool/util.h
index 03e2ca2..33c89d4 100644
--- a/tool/util.h
+++ b/tool/util.h
@@ -50,7 +50,7 @@ typedef union u_APDU APDU;
 void dump_hex(unsigned const char*, unsigned int);
 int set_length(unsigned char*, int);
 int get_length(unsigned char*, int*);
-X509_NAME *parse_name(char*);
+X509_NAME *parse_name(const char*);
 unsigned char get_algorithm(EVP_PKEY*);
 FILE *open_file(const char*, int);
 int get_object_id(enum enum_slot slot);