diff --git a/lib/asn1/gen.c b/lib/asn1/gen.c
index 1d59bc400..27d7aa1d1 100644
--- a/lib/asn1/gen.c
+++ b/lib/asn1/gen.c
@@ -751,6 +751,118 @@ generate_type_free (Symbol *s)
   fprintf (codefile, "}\n\n");
 }
 
+static void
+length_primitive (char *typename, char *name, char *variable)
+{
+    fprintf (codefile, "%s += length_%s(%s);\n", variable, typename, name);
+}
+
+static void
+length_type (char *name, Type *t, char *variable)
+{
+  switch (t->type) {
+  case TType:
+#if 0
+      length_type (name, t->symbol->type);
+#endif
+      fprintf (codefile, "%s += length_%s(%s);\n",
+	       variable, t->symbol->gen_name, name);
+      break;
+  case TInteger:
+      length_primitive ("integer", name, variable);
+      break;
+  case TOctetString:
+      length_primitive ("octet_string", name, variable);
+      break;
+  case TBitString: {
+      /*
+       * XXX - Hope this is correct
+       * look at TBitString case in `encode_type'
+       */
+      fprintf (codefile, "%s += 7;\n", variable);
+      break;
+  }
+  case TSequence: {
+      Member *m;
+      int tag = -1;
+
+      if (t->members == NULL)
+	  break;
+      
+      for (m = t->members; m && tag != m->val; m = m->next) {
+	  char *s = malloc(2 + strlen(name) + 1 + strlen(m->gen_name) + 3);
+
+	  sprintf (s, "%s(%s)->%s", m->optional ? "" : "&", name, m->gen_name);
+	  if (m->optional)
+	      fprintf (codefile, "if(%s)", s);
+	  fprintf (codefile, "{\n"
+		   "int oldret = %s;\n"
+		   "%s = 0;\n", variable, variable);
+	  length_type (s, m->type, "ret");
+	  fprintf (codefile, "%s += 1 + length_len(%s) + oldret;\n",
+		   variable, variable);
+	  fprintf (codefile, "}\n");
+	  if (tag == -1)
+	      tag = m->val;
+	  free (s);
+      }
+      fprintf (codefile,
+	       "%s += 1 + length_len(%s);\n", variable, variable);
+      break;
+  }
+  case TSequenceOf: {
+      char *n = malloc(2*strlen(name) + 20);
+
+      fprintf (codefile,
+	       "{\n"
+	       "int oldret = %s;\n"
+	       "%s = 0;\n", variable, variable);
+
+      fprintf (codefile, "while((%s)->len){\n", name);
+      sprintf (n, "&(%s)->val[(%s)->len-1]", name, name);
+      length_type(n, t->subtype, variable);
+      fprintf(codefile, 
+	      "(%s)->len--;\n"
+	      "}\n",
+	      name);
+      fprintf (codefile,
+	       "%s += 1 + length_len(%s) + oldret;\n"
+	       "}\n", variable, variable);
+      free(n);
+      break;
+  }
+  case TGeneralizedTime:
+      length_primitive ("generalized_time", name, variable);
+      break;
+  case TGeneralString:
+      length_primitive ("general_string", name, variable);
+      break;
+  case TApplication:
+      length_type (name, t->subtype, variable);
+      fprintf (codefile, "ret += 1 + length_len (ret);\n");
+      break;
+  default :
+      abort ();
+  }
+}
+
+static void
+generate_type_length (Symbol *s)
+{
+  fprintf (headerfile,
+	   "size_t length_%s(%s *);\n",
+	   s->gen_name, s->gen_name);
+
+  fprintf (codefile,
+	   "size_t\n"
+	   "length_%s(%s *data)\n"
+	   "{\n"
+	   "size_t ret = 0;\n",
+	   s->gen_name, s->gen_name);
+
+  length_type ("data", s->type, "ret");
+  fprintf (codefile, "return ret;\n}\n\n");
+}
 
 void
 generate_type (Symbol *s)
@@ -759,4 +871,5 @@ generate_type (Symbol *s)
   generate_type_encode (s);
   generate_type_decode (s);
   generate_type_free (s);
+  generate_type_length (s);
 }