From: Álvaro Fernández Rojas <noltari@gmail.com>
Date: Tue, 16 Dec 2025 12:30:49 +0000 (+0100)
Subject: dhcpv6: fix NA/PD=try when NA/PD aren't provided
X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;ds=inline;p=project%2Fodhcp6c.git

dhcpv6: fix NA/PD=try when NA/PD aren't provided

Fixes infinite SOLICIT loop when NA=try and/or PD=try but the ISP provides
no NA and/or no PD (only SLAAC).

Closes: https://github.com/openwrt/odhcp6c/issues/134
Link: https://github.com/openwrt/odhcp6c/pull/137
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
---

diff --git a/src/dhcpv6.c b/src/dhcpv6.c
index 32a5e47..d8bb8be 100644
--- a/src/dhcpv6.c
+++ b/src/dhcpv6.c
@@ -2064,12 +2064,25 @@ int dhcpv6_promote_server_cand(void)
 	if (!cand_len)
 		return -1;
 
-	if (!cand->ia_pd_len && cand->has_noaddravail && na_mode == IA_MODE_TRY) {
-		na_mode = IA_MODE_NONE;
+	if (!cand->ia_pd_len && cand->has_noaddravail) {
+		bool override = false;
 
-		dhcpv6_retx[DHCPV6_MSG_SOLICIT].max_timeo = cand->sol_max_rt;
-		dhcpv6_retx[DHCPV6_MSG_INFO_REQ].max_timeo = cand->inf_max_rt;
-		return -1;
+		if (na_mode == IA_MODE_TRY) {
+			na_mode = IA_MODE_NONE;
+			override = true;
+		}
+
+		if (pd_mode == IA_MODE_TRY) {
+			pd_mode = IA_MODE_NONE;
+			override = true;
+		}
+
+		if (override) {
+			dhcpv6_retx[DHCPV6_MSG_SOLICIT].max_timeo = cand->sol_max_rt;
+			dhcpv6_retx[DHCPV6_MSG_INFO_REQ].max_timeo = cand->inf_max_rt;
+
+			return -1;
+		}
 	}
 
 	hdr[0] = htons(DHCPV6_OPT_SERVERID);