From: Paul Donald <newtwen+github@gmail.com>
Date: Fri, 10 Oct 2025 11:43:23 +0000 (+0200)
Subject: config: cap ra_retranstime and warn instead of only logging an error
X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=434b0613399721ff50ecef499d595e5f4c5ce003;p=project%2Fodhcpd.git

config: cap ra_retranstime and warn instead of only logging an error

Set to the currently defined maximum of 60,000msec via a define.

Signed-off-by: Paul Donald <newtwen+github@gmail.com>
Link: https://github.com/openwrt/odhcpd/pull/225
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
---

diff --git a/src/config.c b/src/config.c
index 8cc43db..05daf5d 100644
--- a/src/config.c
+++ b/src/config.c
@@ -1371,11 +1371,10 @@ int config_parse_interface(void *data, size_t len, const char *name, bool overwr
 	if ((c = tb[IFACE_ATTR_RA_RETRANSTIME])) {
 		uint32_t ra_retranstime = blobmsg_get_u32(c);
 
-		if (ra_retranstime <= 60000)
-			iface->ra_retranstime = ra_retranstime;
-		else
-			syslog(LOG_ERR, "Invalid %s value configured for interface '%s'",
-					iface_attrs[IFACE_ATTR_RA_RETRANSTIME].name, iface->name);
+		iface->ra_retranstime = ra_retranstime <= RETRANS_TIMER_MAX ? ra_retranstime : RETRANS_TIMER_MAX;
+		if (ra_retranstime > RETRANS_TIMER_MAX)
+			syslog(LOG_WARNING, "Clamped invalid %s value configured for interface '%s' to %d",
+					iface_attrs[IFACE_ATTR_RA_RETRANSTIME].name, iface->name, iface->ra_retranstime);
 	}
 
 	if ((c = tb[IFACE_ATTR_RA_HOPLIMIT])) {
diff --git a/src/router.h b/src/router.h
index 6358493..6d82666 100644
--- a/src/router.h
+++ b/src/router.h
@@ -78,6 +78,11 @@ struct icmpv6_opt {
 	Note: this value is an 8 bit int, so max 255.
 */
 #define AdvCurHopLimit					255
+/* RFC4861 §10 - constants
+	Node constants:
+		RETRANS_TIMER                 1,000 milliseconds
+*/
+#define RETRANS_TIMER_MAX				60000
 
 #define ND_RA_FLAG_PROXY		0x4
 #define ND_RA_PREF_HIGH			(1 << 3)