Instead of calling getuptime() all the time in ARP code, do it only

once per function.  This gives a more consistent time value.
OK claudio@ miod@ mvs@

diff --git a/sys/netinet/if_ether.c b/sys/netinet/if_ether.c
index e6615ca..d72190d 100644 (file)
--- a/sys/netinet/if_ether.c
+++ b/sys/netinet/if_ether.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: if_ether.c,v 1.248 2021/04/28 21:21:44 bluhm Exp $    */
+/*     $OpenBSD: if_ether.c,v 1.249 2022/06/27 12:47:07 bluhm Exp $    */
 /*     $NetBSD: if_ether.c,v 1.31 1996/05/11 12:59:58 mycroft Exp $    */
 
 /*
@@ -124,14 +124,16 @@ arptimer(void *arg)
 {
        struct timeout *to = arg;
        struct llinfo_arp *la, *nla;
+       time_t uptime;
 
        NET_LOCK();
+       uptime = getuptime();
        timeout_add_sec(to, arpt_prune);
        /* Net lock is exclusive, no arp mutex needed for arp_list here. */
        LIST_FOREACH_SAFE(la, &arp_list, la_list, nla) {
                struct rtentry *rt = la->la_rt;
 
-               if (rt->rt_expire && rt->rt_expire < getuptime())
+               if (rt->rt_expire && rt->rt_expire < uptime)
                        arptfree(rt); /* timer has expired; clear */
        }
        NET_UNLOCK();
@@ -154,6 +156,7 @@ arp_rtrequest(struct ifnet *ifp, int req, struct rtentry *rt)
 {
        struct sockaddr *gate = rt->rt_gateway;
        struct llinfo_arp *la = (struct llinfo_arp *)rt->rt_llinfo;
+       time_t uptime;
 
        NET_ASSERT_LOCKED();
 
@@ -161,8 +164,8 @@ arp_rtrequest(struct ifnet *ifp, int req, struct rtentry *rt)
            RTF_GATEWAY|RTF_BROADCAST|RTF_MULTICAST|RTF_MPLS))
                return;
 
+       uptime = getuptime();
        switch (req) {
-
        case RTM_ADD:
                if (rt->rt_flags & RTF_CLONING) {
                        rt->rt_expire = 0;
@@ -206,7 +209,7 @@ arp_rtrequest(struct ifnet *ifp, int req, struct rtentry *rt)
                la->la_rt = rt;
                rt->rt_flags |= RTF_LLINFO;
                if ((rt->rt_flags & RTF_LOCAL) == 0)
-                       rt->rt_expire = getuptime();
+                       rt->rt_expire = uptime;
                mtx_enter(&arp_mtx);
                LIST_INSERT_HEAD(&arp_list, la, la_list);
                mtx_leave(&arp_mtx);
@@ -325,6 +328,7 @@ arpresolve(struct ifnet *ifp, struct rtentry *rt0, struct mbuf *m,
        struct sockaddr_dl *sdl;
        struct rtentry *rt = NULL;
        char addr[INET_ADDRSTRLEN];
+       time_t uptime;
 
        if (m->m_flags & M_BCAST) {     /* broadcast */
                memcpy(desten, etherbroadcastaddr, sizeof(etherbroadcastaddr));
@@ -335,10 +339,11 @@ arpresolve(struct ifnet *ifp, struct rtentry *rt0, struct mbuf *m,
                return (0);
        }
 
+       uptime = getuptime();
        rt = rt_getll(rt0);
 
        if (ISSET(rt->rt_flags, RTF_REJECT) &&
-           (rt->rt_expire == 0 || rt->rt_expire > getuptime() )) {
+           (rt->rt_expire == 0 || rt->rt_expire > uptime)) {
                m_freem(m);
                return (rt == rt0 ? EHOSTDOWN : EHOSTUNREACH);
        }
@@ -366,15 +371,15 @@ arpresolve(struct ifnet *ifp, struct rtentry *rt0, struct mbuf *m,
         * Check the address family and length is valid, the address
         * is resolved; otherwise, try to resolve.
         */
-       if ((rt->rt_expire == 0 || rt->rt_expire > getuptime()) &&
+       if ((rt->rt_expire == 0 || rt->rt_expire > uptime) &&
            sdl->sdl_family == AF_LINK && sdl->sdl_alen != 0) {
                memcpy(desten, LLADDR(sdl), sdl->sdl_alen);
 
                /* refresh ARP entry when timeout gets close */
                if (rt->rt_expire != 0 &&
-                   rt->rt_expire - arpt_keep / 8 < getuptime() &&
-                   la->la_refreshed + 30 < getuptime()) {
-                       la->la_refreshed = getuptime();
+                   rt->rt_expire - arpt_keep / 8 < uptime &&
+                   la->la_refreshed + 30 < uptime) {
+                       la->la_refreshed = uptime;
                        arprequest(ifp,
                            &satosin(rt->rt_ifa->ifa_addr)->sin_addr.s_addr,
                            &satosin(dst)->sin_addr.s_addr,
@@ -407,13 +412,13 @@ arpresolve(struct ifnet *ifp, struct rtentry *rt0, struct mbuf *m,
                /* This should never happen. (Should it? -gwr) */
                printf("%s: unresolved and rt_expire == 0\n", __func__);
                /* Set expiration time to now (expired). */
-               rt->rt_expire = getuptime();
+               rt->rt_expire = uptime;
        }
 #endif
        if (rt->rt_expire) {
                rt->rt_flags &= ~RTF_REJECT;
-               if (la->la_asked == 0 || rt->rt_expire != getuptime()) {
-                       rt->rt_expire = getuptime();
+               if (la->la_asked == 0 || rt->rt_expire != uptime) {
+                       rt->rt_expire = uptime;
                        if (la->la_asked++ < arp_maxtries)
                                arprequest(ifp,
                                    &satosin(rt->rt_ifa->ifa_addr)->sin_addr.s_addr,
@@ -613,6 +618,7 @@ arpcache(struct ifnet *ifp, struct ether_arp *ea, struct rtentry *rt)
        struct ifnet *rifp;
        struct mbuf_list ml;
        struct mbuf *m;
+       time_t uptime;
        unsigned int len;
        int changed = 0;
 
@@ -626,6 +632,7 @@ arpcache(struct ifnet *ifp, struct ether_arp *ea, struct rtentry *rt)
        if (la == NULL)
                return (0);
 
+       uptime = getuptime();
        if (sdl->sdl_alen > 0) {
                if (memcmp(ea->arp_sha, LLADDR(sdl), sdl->sdl_alen)) {
                        if (ISSET(rt->rt_flags, RTF_PERMANENT_ARP|RTF_LOCAL)) {
@@ -675,7 +682,7 @@ arpcache(struct ifnet *ifp, struct ether_arp *ea, struct rtentry *rt)
        sdl->sdl_alen = sizeof(ea->arp_sha);
        memcpy(LLADDR(sdl), ea->arp_sha, sizeof(ea->arp_sha));
        if (rt->rt_expire)
-               rt->rt_expire = getuptime() + arpt_keep;
+               rt->rt_expire = uptime + arpt_keep;
        rt->rt_flags &= ~RTF_REJECT;
 
        /* Notify userland that an ARP resolution has been done. */