git: 196a0eb2b84b - stable/15 - in6: Add a helper function to compute expiry times

The branch stable/15 has been updated by markj:

URL: https://cgit.FreeBSD.org/src/commit/?id=196a0eb2b84b63a595f84679acc8d161ab0e29e9

commit 196a0eb2b84b63a595f84679acc8d161ab0e29e9
Author:     Mark Johnston <markj@FreeBSD.org>
AuthorDate: 2026-01-12 13:49:34 +0000
Commit:     Mark Johnston <markj@FreeBSD.org>
CommitDate: 2026-01-27 14:10:47 +0000

    in6: Add a helper function to compute expiry times
    
    Tidy up a bunch of places that have the same duplicated logic.  Simplify
    callers of in6_init_prefix_ltimes().  No functional change intended.
    
    Reviewed by:    pouria, zlei, tuexen, glebius
    MFC after:      2 weeks
    Sponsored by:   OPNsense
    Sponsored by:   Klara, Inc.
    Differential Revision:  https://reviews.freebsd.org/D54561
    
    (cherry picked from commit fb08f80eaf90eb7ace202d8604634fc181be8980)
---
 sys/netinet6/in6.c     | 23 +++++++++++++----------
 sys/netinet6/in6.h     |  2 ++
 sys/netinet6/nd6_rtr.c | 38 +++++++-------------------------------
 3 files changed, 22 insertions(+), 41 deletions(-)

diff --git a/sys/netinet6/in6.c b/sys/netinet6/in6.c
index b98703bdfbfe..cd75d22fa527 100644
--- a/sys/netinet6/in6.c
+++ b/sys/netinet6/in6.c
@@ -1032,6 +1032,15 @@ in6_alloc_ifa(struct ifnet *ifp, struct in6_aliasreq *ifra, int flags)
 	return (ia);
 }
 
+time_t
+in6_expire_time(uint32_t ltime)
+{
+	if (ltime == ND6_INFINITE_LIFETIME)
+		return (0);
+	else
+		return (time_uptime + ltime);
+}
+
 /*
  * Update/configure interface address parameters:
  *
@@ -1054,16 +1063,10 @@ in6_update_ifa_internal(struct ifnet *ifp, struct in6_aliasreq *ifra,
 	 * these members for applications.
 	 */
 	ia->ia6_lifetime = ifra->ifra_lifetime;
-	if (ia->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) {
-		ia->ia6_lifetime.ia6t_expire =
-		    time_uptime + ia->ia6_lifetime.ia6t_vltime;
-	} else
-		ia->ia6_lifetime.ia6t_expire = 0;
-	if (ia->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) {
-		ia->ia6_lifetime.ia6t_preferred =
-		    time_uptime + ia->ia6_lifetime.ia6t_pltime;
-	} else
-		ia->ia6_lifetime.ia6t_preferred = 0;
+	ia->ia6_lifetime.ia6t_expire =
+	    in6_expire_time(ifra->ifra_lifetime.ia6t_vltime);
+	ia->ia6_lifetime.ia6t_preferred =
+	    in6_expire_time(ifra->ifra_lifetime.ia6t_pltime);
 
 	/*
 	 * backward compatibility - if IN6_IFF_DEPRECATED is set from the
diff --git a/sys/netinet6/in6.h b/sys/netinet6/in6.h
index 67c3ccbb1be8..fd2e18b4695b 100644
--- a/sys/netinet6/in6.h
+++ b/sys/netinet6/in6.h
@@ -668,6 +668,8 @@ int	in6_cksum_partial_l2(struct mbuf *m, uint8_t nxt, uint32_t off_l3,
 	    uint32_t off_l4, uint32_t len, uint32_t cov);
 int	in6_cksum_pseudo(struct ip6_hdr *, uint32_t, uint8_t, uint16_t);
 
+time_t	in6_expire_time(uint32_t);
+
 int	in6_localaddr(struct in6_addr *);
 int	in6_localip(struct in6_addr *);
 bool	in6_localip_fib(struct in6_addr *, uint16_t);
diff --git a/sys/netinet6/nd6_rtr.c b/sys/netinet6/nd6_rtr.c
index b9af0a78a584..0f3e855f5b4d 100644
--- a/sys/netinet6/nd6_rtr.c
+++ b/sys/netinet6/nd6_rtr.c
@@ -1141,39 +1141,18 @@ restart:
 	return (n);
 }
 
-static int
+static void
 in6_init_prefix_ltimes(struct nd_prefix *ndpr)
 {
-	if (ndpr->ndpr_pltime == ND6_INFINITE_LIFETIME)
-		ndpr->ndpr_preferred = 0;
-	else
-		ndpr->ndpr_preferred = time_uptime + ndpr->ndpr_pltime;
-	if (ndpr->ndpr_vltime == ND6_INFINITE_LIFETIME)
-		ndpr->ndpr_expire = 0;
-	else
-		ndpr->ndpr_expire = time_uptime + ndpr->ndpr_vltime;
-
-	return 0;
+	ndpr->ndpr_preferred = in6_expire_time(ndpr->ndpr_pltime);
+	ndpr->ndpr_expire = in6_expire_time(ndpr->ndpr_vltime);
 }
 
 static void
 in6_init_address_ltimes(struct nd_prefix *new, struct in6_addrlifetime *lt6)
 {
-	/* init ia6t_expire */
-	if (lt6->ia6t_vltime == ND6_INFINITE_LIFETIME)
-		lt6->ia6t_expire = 0;
-	else {
-		lt6->ia6t_expire = time_uptime;
-		lt6->ia6t_expire += lt6->ia6t_vltime;
-	}
-
-	/* init ia6t_preferred */
-	if (lt6->ia6t_pltime == ND6_INFINITE_LIFETIME)
-		lt6->ia6t_preferred = 0;
-	else {
-		lt6->ia6t_preferred = time_uptime;
-		lt6->ia6t_preferred += lt6->ia6t_pltime;
-	}
+	lt6->ia6t_preferred = in6_expire_time(lt6->ia6t_pltime);
+	lt6->ia6t_expire = in6_expire_time(lt6->ia6t_vltime);
 }
 
 static struct in6_ifaddr *
@@ -1357,11 +1336,8 @@ nd6_prelist_add(struct nd_prefixctl *pr, struct nd_defrouter *dr,
 	new->ndpr_vltime = pr->ndpr_vltime;
 	new->ndpr_pltime = pr->ndpr_pltime;
 	new->ndpr_flags = pr->ndpr_flags;
-	if ((error = in6_init_prefix_ltimes(new)) != 0) {
-		free(new, M_IP6NDP);
-		return (error);
-	}
 	new->ndpr_lastupdate = time_uptime;
+	in6_init_prefix_ltimes(new);
 
 	/* initialization */
 	LIST_INIT(&new->ndpr_advrtrs);
@@ -1504,7 +1480,7 @@ prelist_update(struct nd_prefixctl *new, struct nd_defrouter *dr,
 		if (new->ndpr_raf_onlink) {
 			pr->ndpr_vltime = new->ndpr_vltime;
 			pr->ndpr_pltime = new->ndpr_pltime;
-			(void)in6_init_prefix_ltimes(pr); /* XXX error case? */
+			in6_init_prefix_ltimes(pr);
 			pr->ndpr_lastupdate = time_uptime;
 		}