Allow to change fold_max variable.

src/client/rspamc.c

@@ -951,7 +951,9 @@ rspamc_mime_output (FILE *out, ucl_object_t *result, GString *input, GError *err
 			g_string_erase (symbuf, symbuf->len - 1, 1);
 		}
 
-		folded_symbuf = rspamd_header_value_fold ("X-Spam-Symbols", symbuf->str);
+		folded_symbuf = rspamd_header_value_fold ("X-Spam-Symbols",
+				symbuf->str,
+				0);
 		g_mime_object_append_header (GMIME_OBJECT (message), "X-Spam-Symbols",
 				symbuf->str);
 		g_string_free (folded_symbuf, TRUE);

src/libutil/str_util.c

@@ -865,10 +865,12 @@ rspamd_strings_levenshtein_distance (const gchar *s1, gsize s1len,
 }
 
 GString *
-rspamd_header_value_fold (const gchar *name, const gchar *value)
+rspamd_header_value_fold (const gchar *name,
+		const gchar *value,
+		guint fold_max)
 {
 	GString *res;
-	const guint fold_max = 76;
+	const guint default_fold_max = 76;
 	guint cur_len;
 	const gchar *p, *c;
 	gboolean first_token = TRUE;
@@ -886,6 +888,11 @@ rspamd_header_value_fold (const gchar *name, const gchar *value)
 	g_assert (name != NULL);
 	g_assert (value != NULL);
 
+	/* Filter insane values */
+	if (fold_max < 20) {
+		fold_max = default_fold_max;
+	}
+
 	res = g_string_sized_new (strlen (value));
 
 	c = value;

src/libutil/str_util.h

@@ -168,6 +168,8 @@ gint rspamd_strings_levenshtein_distance (const gchar *s1, gsize s1len,
  * @param value value of header
  * @return new GString with the folded value
  */
-GString * rspamd_header_value_fold (const gchar *name, const gchar *value);
+GString *rspamd_header_value_fold (const gchar *name,
+		const gchar *value,
+		guint fold_max);
 
 #endif /* SRC_LIBUTIL_STR_UTIL_H_ */

src/lua/lua_util.c

@@ -613,7 +613,7 @@ lua_util_fold_header (lua_State *L)
 	value = luaL_checkstring (L, 2);
 
 	if (name && value) {
-		folded = rspamd_header_value_fold (name, value);
+		folded = rspamd_header_value_fold (name, value, 0);
 
 		if (folded) {
 			lua_pushlstring (L, folded->str, folded->len);