VLAN: Clean up RTM_NEW/DELLINK processing

This uses couple of additional helper macros and prints more debug
information to make the VLAN events easier to analyze.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>

src/ap/vlan_init.c

@@ -617,6 +617,7 @@ vlan_read_ifnames(struct nlmsghdr *h, size_t len, int del,
 	struct ifinfomsg *ifi;
 	int attrlen, nlmsg_len, rta_len;
 	struct rtattr *attr;
+	char ifname[IFNAMSIZ + 1];
 
 	if (len < sizeof(*ifi))
 		return;
@@ -631,29 +632,39 @@ vlan_read_ifnames(struct nlmsghdr *h, size_t len, int del,
 
 	attr = (struct rtattr *) (((char *) ifi) + nlmsg_len);
 
+	os_memset(ifname, 0, sizeof(ifname));
 	rta_len = RTA_ALIGN(sizeof(struct rtattr));
 	while (RTA_OK(attr, attrlen)) {
-		char ifname[IFNAMSIZ + 1];
-
 		if (attr->rta_type == IFLA_IFNAME) {
 			int n = attr->rta_len - rta_len;
 			if (n < 0)
 				break;
 
-			os_memset(ifname, 0, sizeof(ifname));
-
-			if ((size_t) n > sizeof(ifname))
-				n = sizeof(ifname);
+			if ((size_t) n >= sizeof(ifname))
+				n = sizeof(ifname) - 1;
 			os_memcpy(ifname, ((char *) attr) + rta_len, n);
 
-			if (del)
-				vlan_dellink(ifname, hapd);
-			else
-				vlan_newlink(ifname, hapd);
 		}
 
 		attr = RTA_NEXT(attr, attrlen);
 	}
+
+	if (!ifname[0])
+		return;
+
+	wpa_printf(MSG_DEBUG,
+		   "VLAN: RTM_%sLINK: ifi_index=%d ifname=%s ifi_family=%d ifi_flags=0x%x (%s%s%s%s)",
+		   del ? "DEL" : "NEW",
+		   ifi->ifi_index, ifname, ifi->ifi_family, ifi->ifi_flags,
+		   (ifi->ifi_flags & IFF_UP) ? "[UP]" : "",
+		   (ifi->ifi_flags & IFF_RUNNING) ? "[RUNNING]" : "",
+		   (ifi->ifi_flags & IFF_LOWER_UP) ? "[LOWER_UP]" : "",
+		   (ifi->ifi_flags & IFF_DORMANT) ? "[DORMANT]" : "");
+
+	if (del)
+		vlan_dellink(ifname, hapd);
+	else
+		vlan_newlink(ifname, hapd);
 }
 
 
@@ -677,7 +688,7 @@ static void vlan_event_receive(int sock, void *eloop_ctx, void *sock_ctx)
 	}
 
 	h = (struct nlmsghdr *) buf;
-	while (left >= (int) sizeof(*h)) {
+	while (NLMSG_OK(h, left)) {
 		int len, plen;
 
 		len = h->nlmsg_len;
@@ -698,9 +709,7 @@ static void vlan_event_receive(int sock, void *eloop_ctx, void *sock_ctx)
 			break;
 		}
 
-		len = NLMSG_ALIGN(len);
-		left -= len;
-		h = (struct nlmsghdr *) ((char *) h + len);
+		h = NLMSG_NEXT(h, left);
 	}
 
 	if (left > 0) {