Reduce if_indextoname(3) usage.

Don't ask the kernel to translate an if_index to a name if we are not
running with verbose logging, it's not free.

diff --git a/sbin/slaacd/engine.c b/sbin/slaacd/engine.c
index fafeecf..f50fd6a 100644 (file)
--- a/sbin/slaacd/engine.c
+++ b/sbin/slaacd/engine.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: engine.c,v 1.90 2024/06/03 17:58:33 deraadt Exp $     */
+/*     $OpenBSD: engine.c,v 1.91 2024/07/13 16:06:34 florian Exp $     */
 
 /*
  * Copyright (c) 2017 Florian Obser <florian@openbsd.org>
@@ -968,7 +968,6 @@ iface_state_transition(struct slaacd_iface *iface, enum if_state new_state)
        struct address_proposal *addr_proposal;
        struct dfr_proposal     *dfr_proposal;
        struct rdns_proposal    *rdns_proposal;
-       char                     ifnamebuf[IF_NAMESIZE], *if_name;
 
        iface->state = new_state;
 
@@ -1025,10 +1024,13 @@ iface_state_transition(struct slaacd_iface *iface, enum if_state new_state)
                break;
        }
 
-       if_name = if_indextoname(iface->if_index, ifnamebuf);
-       log_debug("%s[%s] %s -> %s, timo: %lld", __func__, if_name == NULL ?
-           "?" : if_name, if_state_name(old_state), if_state_name(new_state),
-           iface->timo.tv_sec);
+       if (log_getverbose()) {
+               char     ifnamebuf[IF_NAMESIZE], *if_name;
+               if_name = if_indextoname(iface->if_index, ifnamebuf);
+               log_debug("%s[%s] %s -> %s, timo: %lld", __func__,
+                   if_name == NULL ? "?" : if_name, if_state_name(old_state),
+                   if_state_name(new_state), iface->timo.tv_sec);
+       }
 
        if (iface->timo.tv_sec == -1) {
                if (evtimer_pending(&iface->timer, NULL))
@@ -1043,7 +1045,6 @@ void addr_proposal_state_transition(struct address_proposal *addr_proposal,
        enum proposal_state      old_state = addr_proposal->state;
        struct slaacd_iface     *iface;
        uint32_t                 lifetime;
-       char                     ifnamebuf[IF_NAMESIZE], *if_name;
 
        addr_proposal->state = new_state;
 
@@ -1103,11 +1104,14 @@ void addr_proposal_state_transition(struct address_proposal *addr_proposal,
                break;
        }
 
-       if_name = if_indextoname(addr_proposal->if_index, ifnamebuf);
-       log_debug("%s[%s] %s -> %s, timo: %lld", __func__, if_name == NULL ?
-           "?" : if_name, proposal_state_name(old_state),
-           proposal_state_name(new_state),
-           addr_proposal->timo.tv_sec);
+       if (log_getverbose()) {
+               char     ifnamebuf[IF_NAMESIZE], *if_name;
+               if_name = if_indextoname(addr_proposal->if_index, ifnamebuf);
+               log_debug("%s[%s] %s -> %s, timo: %lld", __func__,
+                   if_name == NULL ? "?" : if_name,
+                   proposal_state_name(old_state),
+                   proposal_state_name(new_state), addr_proposal->timo.tv_sec);
+       }
 
        if (addr_proposal->timo.tv_sec == -1) {
                if (evtimer_pending(&addr_proposal->timer, NULL))
@@ -1122,7 +1126,6 @@ void dfr_proposal_state_transition(struct dfr_proposal *dfr_proposal,
        enum proposal_state      old_state = dfr_proposal->state;
        struct slaacd_iface     *iface;
        uint32_t                 lifetime;
-       char                     ifnamebuf[IF_NAMESIZE], *if_name;
 
        dfr_proposal->state = new_state;
 
@@ -1176,11 +1179,15 @@ void dfr_proposal_state_transition(struct dfr_proposal *dfr_proposal,
                break;
        }
 
-       if_name = if_indextoname(dfr_proposal->if_index, ifnamebuf);
-       log_debug("%s[%s] %s -> %s, timo: %lld", __func__, if_name == NULL ?
-           "?" : if_name, proposal_state_name(old_state),
-           proposal_state_name(new_state),
-           dfr_proposal->timo.tv_sec);
+       if (log_getverbose()) {
+               char     ifnamebuf[IF_NAMESIZE], *if_name;
+
+               if_name = if_indextoname(dfr_proposal->if_index, ifnamebuf);
+               log_debug("%s[%s] %s -> %s, timo: %lld", __func__,
+                   if_name == NULL ? "?" : if_name,
+                   proposal_state_name(old_state),
+                   proposal_state_name(new_state), dfr_proposal->timo.tv_sec);
+       }
 
        if (dfr_proposal->timo.tv_sec == -1) {
                if (evtimer_pending(&dfr_proposal->timer, NULL))
@@ -1196,7 +1203,6 @@ void rdns_proposal_state_transition(struct rdns_proposal *rdns_proposal,
        enum proposal_state      old_state = rdns_proposal->state;
        struct slaacd_iface     *iface;
        uint32_t                 lifetime;
-       char                     ifnamebuf[IF_NAMESIZE], *if_name;
 
        rdns_proposal->state = new_state;
 
@@ -1250,11 +1256,15 @@ void rdns_proposal_state_transition(struct rdns_proposal *rdns_proposal,
                break;
        }
 
-       if_name = if_indextoname(rdns_proposal->if_index, ifnamebuf);
-       log_debug("%s[%s] %s -> %s, timo: %lld", __func__, if_name == NULL ?
-           "?" : if_name, proposal_state_name(old_state),
-           proposal_state_name(new_state),
-           rdns_proposal->timo.tv_sec);
+       if (log_getverbose()) {
+               char     ifnamebuf[IF_NAMESIZE], *if_name;
+
+               if_name = if_indextoname(rdns_proposal->if_index, ifnamebuf);
+               log_debug("%s[%s] %s -> %s, timo: %lld", __func__,
+                   if_name == NULL ? "?" : if_name,
+                   proposal_state_name(old_state),
+                   proposal_state_name(new_state), rdns_proposal->timo.tv_sec);
+       }
 
        if (rdns_proposal->timo.tv_sec == -1) {
                if (evtimer_pending(&rdns_proposal->timer, NULL))