With the interface debug flag enabled, print a "score" for each AP we

consider during auto-join.  This can help users determine why a specific
network was chosen.

OK stsp@

diff --git a/sys/net80211/ieee80211_node.c b/sys/net80211/ieee80211_node.c
index 89c086e..04147cc 100644 (file)
--- a/sys/net80211/ieee80211_node.c
+++ b/sys/net80211/ieee80211_node.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: ieee80211_node.c,v 1.148 2018/09/10 10:11:18 phessler Exp $   */
+/*     $OpenBSD: ieee80211_node.c,v 1.149 2018/09/11 10:21:29 phessler Exp $   */
 /*     $NetBSD: ieee80211_node.c,v 1.14 2004/05/09 09:18:47 dyoung Exp $       */
 
 /*-
@@ -410,58 +410,6 @@ ieee80211_add_ess(struct ieee80211com *ic, struct ieee80211_join *join)
        return (0);
 }
 
-int
-ieee80211_ess_cmp_crypto(struct ieee80211_node *nicur,
-    struct ieee80211_node *nican)
-{
-       if ((nican->ni_rsnprotos & IEEE80211_PROTO_RSN) &&
-           (nicur->ni_rsnprotos & IEEE80211_PROTO_RSN) == 0)
-               return 1;
-       if ((nican->ni_rsnprotos & IEEE80211_PROTO_RSN) == 0 &&
-           (nicur->ni_rsnprotos & IEEE80211_PROTO_RSN))
-               return -1;
-
-       if ((nican->ni_rsnprotos & IEEE80211_PROTO_WPA) &&
-           (nicur->ni_rsnprotos & IEEE80211_PROTO_WPA) == 0)
-               return 1;
-       if ((nican->ni_rsnprotos & IEEE80211_PROTO_WPA) == 0 &&
-           (nicur->ni_rsnprotos & IEEE80211_PROTO_WPA))
-               return -1;
-
-       if ((nican->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) &&
-           (nicur->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0)
-               return 1;
-       if ((nican->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0 &&
-           (nicur->ni_capinfo & IEEE80211_CAPINFO_PRIVACY))
-               return -1;
-
-       return 0;
-}
-
-int
-ieee80211_ess_cmp_band(struct ieee80211com *ic,
-    struct ieee80211_node *nicur, struct ieee80211_node *nican)
-{
-       uint8_t min_5ghz_rssi;
-
-       if (ic->ic_max_rssi)
-               min_5ghz_rssi = IEEE80211_RSSI_THRES_RATIO_5GHZ;
-       else
-               min_5ghz_rssi = (uint8_t)IEEE80211_RSSI_THRES_5GHZ;
-
-       if (IEEE80211_IS_CHAN_5GHZ(nican->ni_chan) &&
-           IEEE80211_IS_CHAN_2GHZ(nicur->ni_chan) &&
-           nican->ni_rssi > min_5ghz_rssi)
-               return 1;
-
-       if (IEEE80211_IS_CHAN_5GHZ(nicur->ni_chan) &&
-           IEEE80211_IS_CHAN_5GHZ(nican->ni_chan) &&
-           nicur->ni_rssi > min_5ghz_rssi)
-               return -1;
-
-       return 0;
-}
-
 uint8_t
 ieee80211_ess_adjust_rssi(struct ieee80211com *ic, struct ieee80211_node *ni)
 {
@@ -486,18 +434,31 @@ ieee80211_ess_adjust_rssi(struct ieee80211com *ic, struct ieee80211_node *ni)
 }
 
 int
-ieee80211_ess_cmp_rssi(struct ieee80211com *ic,
-    struct ieee80211_node *nicur, struct ieee80211_node *nican)
+ieee80211_ess_calculate_score(struct ieee80211com *ic,
+    struct ieee80211_node *ni)
 {
-       uint8_t cur_rssi = ieee80211_ess_adjust_rssi(ic, nicur);
-       uint8_t can_rssi = ieee80211_ess_adjust_rssi(ic, nican);
+       int score = 0;
+       uint8_t min_5ghz_rssi;
 
-       if (can_rssi > cur_rssi)
-               return 1;
-       if (cur_rssi > can_rssi)
-               return -1;
+       if (ic->ic_max_rssi)
+               min_5ghz_rssi = IEEE80211_RSSI_THRES_RATIO_5GHZ;
+       else
+               min_5ghz_rssi = (uint8_t)IEEE80211_RSSI_THRES_5GHZ;
+
+       /* Calculate the crypto score */
+       if (ni->ni_rsnprotos & IEEE80211_PROTO_RSN)
+               score += 16;
+       if (ni->ni_rsnprotos & IEEE80211_PROTO_WPA)
+               score += 8;
+       if (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY)
+               score += 4;
+
+       /* 5GHz with a good signal */
+       if (IEEE80211_IS_CHAN_5GHZ(ni->ni_chan) &&
+           ni->ni_rssi > min_5ghz_rssi)
+               score += 2;
 
-       return 0;
+       return score;
 }
 
 /*
@@ -515,39 +476,24 @@ int
 ieee80211_ess_is_better(struct ieee80211com *ic,
     struct ieee80211_node *nicur, struct ieee80211_node *nican)
 {
-       int score_cur = 0, score_can = 0;
+       struct ifnet            *ifp = &ic->ic_if;
+       int                      score_cur = 0, score_can = 0;
+       int                      cur_rssi, can_rssi;
 
-       switch (ieee80211_ess_cmp_crypto(nicur, nican)) {
-       case 1:
-               score_can += 4;
-               break;
-       case -1:
-               score_cur += 4;
-               break;
-       default:
-               break;
-       }
-               
-       switch (ieee80211_ess_cmp_band(ic, nicur, nican)) {
-       case 1:
-               score_can += 2;
-               break;
-       case -1:
-               score_cur += 2;
-               break;
-       default:
-               break;
-       }
+       score_cur = ieee80211_ess_calculate_score(ic, nicur);
+       score_can = ieee80211_ess_calculate_score(ic, nican);
 
-       switch (ieee80211_ess_cmp_rssi(ic, nicur, nican)) {
-       case 1:
-               score_can += 1;
-               break;
-       case -1:
-               score_cur += 1;
-               break;
-       default:
-               break;
+       cur_rssi = ieee80211_ess_adjust_rssi(ic, nicur);
+       can_rssi = ieee80211_ess_adjust_rssi(ic, nican);
+
+       if (can_rssi > cur_rssi)
+               score_can++;
+
+       if ((ifp->if_flags & IFF_DEBUG) && (score_can <= score_cur)) {
+               printf("%s: AP %s ", ifp->if_xname,
+                   ether_sprintf(nican->ni_bssid));
+               ieee80211_print_essid(nican->ni_essid, nican->ni_esslen);
+               printf(" score %u\n", score_can);
        }
 
        return score_can > score_cur;
@@ -631,6 +577,12 @@ ieee80211_switch_ess(struct ieee80211com *ic)
            (memcmp(ic->ic_des_essid, seless->essid,
             IEEE80211_NWID_LEN) == 0))) {
                if (ifp->if_flags & IFF_DEBUG) {
+                       printf("%s: best AP %s ", ifp->if_xname,
+                           ether_sprintf(selni->ni_bssid));
+                       ieee80211_print_essid(selni->ni_essid,
+                           selni->ni_esslen);
+                       printf(" score %u\n",
+                           ieee80211_ess_calculate_score(ic, selni));
                        printf("%s: switching to network ", ifp->if_xname);
                        ieee80211_print_essid(seless->essid, seless->esslen);
                        printf("\n");