1 files changed, 22 insertions, 7 deletions

diff --git a/networking/udhcp/common.c b/networking/udhcp/common.c
index 31e525cb0..8e9b93655 100644
--- a/networking/udhcp/common.c
+++ b/networking/udhcp/common.c
@@ -404,14 +404,29 @@ void FAST_FUNC udhcp_add_simple_option(struct dhcp_packet *packet, uint8_t code,
 #endif
 
 /* Find option 'code' in opt_list */
-struct option_set* FAST_FUNC udhcp_find_option(struct option_set *opt_list, uint8_t code)
+struct option_set* FAST_FUNC udhcp_find_option(struct option_set *opt_list, uint8_t code, bool dhcpv6)
 {
-        while (opt_list && opt_list->data[OPT_CODE] < code)
-                opt_list = opt_list->next;
+        IF_NOT_UDHCPC6(bool dhcpv6 = 0;)
+        uint8_t cur_code;
 
-        if (opt_list && opt_list->data[OPT_CODE] == code)
-                return opt_list;
-        return NULL;
+        for (;;) {
+                if (!opt_list)
+                        return opt_list; /* NULL */
+                if (!dhcpv6) {
+                        cur_code = opt_list->data[OPT_CODE];
+                } else {
+//FIXME: add support for code > 0xff
+                        if (opt_list->data[D6_OPT_CODE] != 0)
+                                return NULL;
+                        cur_code = opt_list->data[D6_OPT_CODE + 1];
+                }
+                if (cur_code >= code) {
+                        if (cur_code == code)
+                                return opt_list;
+                        return NULL;
+                }
+                opt_list = opt_list->next;
+        }
 }
 
 /* Parse string to IP in network order */
@@ -499,7 +514,7 @@ static NOINLINE void attach_option(
         }
 #endif
 
-        existing = udhcp_find_option(*opt_list, optflag->code);
+        existing = udhcp_find_option(*opt_list, optflag->code, dhcpv6);
         if (!existing) {
                 /* make a new option */
                 uint8_t *p = udhcp_insert_new_option(opt_list, optflag->code, length, dhcpv6);