From: Roy Marples <roy@marples.name>
Date: Sat, 26 Jan 2019 00:08:43 +0000 (+0000)
Subject: BSD: treat LINK_STATE_UNKNOWN as DOWN if media is invalid
X-Git-Tag: v7.1.1~9
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6deb24e6c8671b470d7b0de00a4d751f532bd5c1;p=thirdparty%2Fdhcpcd.git

BSD: treat LINK_STATE_UNKNOWN as DOWN if media is invalid

On BSD, some interfaces might emit RTM_IFINFO before the link state
has initialised. Mainly wireless cards.
If the intial carrier call says media state change is valid,
we need to treat LINK_STATE_UNKNOWN as LINK_DOWN rather than
LINK_UP.
---

diff --git a/src/dhcpcd.h b/src/dhcpcd.h
index 16b9ad25..b395c18d 100644
--- a/src/dhcpcd.h
+++ b/src/dhcpcd.h
@@ -84,7 +84,8 @@ struct interface {
 	unsigned short vlanid;
 	unsigned int metric;
 	int carrier;
-	int wireless;
+	bool media_valid;
+	bool wireless;
 	uint8_t ssid[IF_SSIDLEN + 1]; /* NULL terminated */
 	unsigned int ssid_len;
 
diff --git a/src/if-bsd.c b/src/if-bsd.c
index a5338624..5ec60eb5 100644
--- a/src/if-bsd.c
+++ b/src/if-bsd.c
@@ -946,16 +946,22 @@ if_ifinfo(struct dhcpcd_ctx *ctx, const struct if_msghdr *ifm)
 	if ((ifp = if_findindex(ctx->ifaces, ifm->ifm_index)) == NULL)
 		return;
 
-	/* If we get LINK_STATE_UNKNOWN here, it means the interface
-	 * doesn't support reporting carrier state.
-	 * As such, we need to rely on IFF_UP.
-	 * Even if LINK_STATE_UP is reported, we also need IFF_UP as well
-	 * so for dhcpcd they are equivalent and we only need to check
-	 * LINK_STATE_DOWN. */
-	if (ifm->ifm_data.ifi_link_state == LINK_STATE_DOWN)
-		link_state = LINK_DOWN;
-	else
+	switch (ifm->ifm_data.ifi_link_state) {
+	case LINK_STATE_UNKNOWN:
+		if (ifp->media_valid) {
+			link_state = LINK_DOWN;
+			break;
+		}
+		/* Interface does not report media state, so we have
+		 * to rely on IFF_UP. */
+		/* FALLTHROUGH */
+	case LINK_STATE_UP:
 		link_state = ifm->ifm_flags & IFF_UP ? LINK_UP : LINK_DOWN;
+		break;
+	default:
+		link_state = LINK_DOWN;
+		break;
+	}
 
 	dhcpcd_handlecarrier(ctx, link_state,
 	    (unsigned int)ifm->ifm_flags, ifp->name);
diff --git a/src/if.c b/src/if.c
index 8590e6e0..e8950d7e 100644
--- a/src/if.c
+++ b/src/if.c
@@ -155,9 +155,13 @@ if_carrier(struct interface *ifp)
 	strlcpy(ifmr.ifm_name, ifp->name, sizeof(ifmr.ifm_name));
 	if (ioctl(ifp->ctx->pf_inet_fd, SIOCGIFMEDIA, &ifmr) != -1 &&
 	    ifmr.ifm_status & IFM_AVALID)
+	{
+		ifp->media_valid = true;
 		r = (ifmr.ifm_status & IFM_ACTIVE) ? LINK_UP : LINK_DOWN;
-	else
+	} else {
+		ifp->media_valid = false;
 		r = ifr.ifr_flags & IFF_RUNNING ? LINK_UP : LINK_UNKNOWN;
+	}
 #else
 	r = ifr.ifr_flags & IFF_RUNNING ? LINK_UP : LINK_DOWN;
 #endif
@@ -592,7 +596,7 @@ if_discover(struct dhcpcd_ctx *ctx, struct ifaddrs **ifaddrs,
 		 * we can work them out. */
 		ifp->metric = 200 + ifp->index;
 		if (if_getssid(ifp) != -1) {
-			ifp->wireless = 1;
+			ifp->wireless = true;
 			ifp->metric += 100;
 		}
 #endif