zebra: use the dataplane to read netlink intf addr changes

Read incoming interface address change notifications in the
dplane pthread; enqueue the events to the main pthread
for processing. This is netlink-only for now - the bsd
kernel socket path remains unchanged.

Signed-off-by: Mark Stapp <mjs.ietf@gmail.com>

1 files changed, 60 insertions, 17 deletions

diff --git a/zebra/kernel_netlink.c b/zebra/kernel_netlink.c
index f50fd74ac1..602bdc1dc5 100644
--- a/zebra/kernel_netlink.c
+++ b/zebra/kernel_netlink.c
@@ -324,6 +324,10 @@ static int netlink_socket(struct nlsock *nl, unsigned long groups,
 	return ret;
 }
 
+/*
+ * Dispatch an incoming netlink message; used by the zebra main pthread's
+ * netlink event reader.
+ */
 static int netlink_information_fetch(struct nlmsghdr *h, ns_id_t ns_id,
 				     int startup)
 {
@@ -345,10 +349,6 @@ static int netlink_information_fetch(struct nlmsghdr *h, ns_id_t ns_id,
 		return netlink_link_change(h, ns_id, startup);
 	case RTM_DELLINK:
 		return netlink_link_change(h, ns_id, startup);
-	case RTM_NEWADDR:
-		return netlink_interface_addr(h, ns_id, startup);
-	case RTM_DELADDR:
-		return netlink_interface_addr(h, ns_id, startup);
 	case RTM_NEWNEIGH:
 	case RTM_DELNEIGH:
 	case RTM_GETNEIGH:
@@ -361,6 +361,12 @@ static int netlink_information_fetch(struct nlmsghdr *h, ns_id_t ns_id,
 		return netlink_nexthop_change(h, ns_id, startup);
 	case RTM_DELNEXTHOP:
 		return netlink_nexthop_change(h, ns_id, startup);
+
+	/* Messages handled in the dplane thread */
+	case RTM_NEWADDR:
+	case RTM_DELADDR:
+		return 0;
+
 	default:
 		/*
 		 * If we have received this message then
@@ -378,6 +384,32 @@ static int netlink_information_fetch(struct nlmsghdr *h, ns_id_t ns_id,
 	return 0;
 }
 
+/*
+ * Dispatch an incoming netlink message; used by the dataplane pthread's
+ * netlink event reader code.
+ */
+static int dplane_netlink_information_fetch(struct nlmsghdr *h, ns_id_t ns_id,
+					    int startup)
+{
+	/*
+	 * Dispatch the incoming messages that the dplane pthread handles
+	 */
+	switch (h->nlmsg_type) {
+	case RTM_NEWADDR:
+	case RTM_DELADDR:
+		return netlink_interface_addr_dplane(h, ns_id, startup);
+
+	/* TODO */
+	case RTM_NEWLINK:
+	case RTM_DELLINK:
+
+	default:
+		break;
+	}
+
+	return 0;
+}
+
 static int kernel_read(struct thread *thread)
 {
 	struct zebra_ns *zns = (struct zebra_ns *)THREAD_ARG(thread);
@@ -388,7 +420,7 @@ static int kernel_read(struct thread *thread)
 
 	netlink_parse_info(netlink_information_fetch, &zns->netlink, &dp_info,
 			   5, 0);
-	zns->t_netlink = NULL;
+
 	thread_add_read(zrouter.master, kernel_read, zns, zns->netlink.sock,
 			&zns->t_netlink);
 
@@ -396,6 +428,17 @@ static int kernel_read(struct thread *thread)
 }
 
 /*
+ * Called by the dplane pthread to read incoming OS messages and dispatch them.
+ */
+int kernel_dplane_read(struct zebra_dplane_info *info)
+{
+	netlink_parse_info(dplane_netlink_information_fetch, &info->nls, info,
+			   5, 0);
+
+	return 0;
+}
+
+/*
  * Filter out messages from self that occur on listener socket,
  * caused by our actions on the command socket(s)
  *
@@ -476,9 +519,8 @@ static void netlink_install_filter(int sock, uint32_t pid, uint32_t dplane_pid)
 			     safe_strerror(errno));
 }
 
-void netlink_parse_rtattr_flags(struct rtattr **tb, int max,
-				struct rtattr *rta, int len,
-				unsigned short flags)
+void netlink_parse_rtattr_flags(struct rtattr **tb, int max, struct rtattr *rta,
+				int len, unsigned short flags)
 {
 	unsigned short type;
 
@@ -800,8 +842,7 @@ static int netlink_recv_msg(const struct nlsock *nl, struct msghdr msg,
  * ignored, -1 otherwise.
  */
 static int netlink_parse_error(const struct nlsock *nl, struct nlmsghdr *h,
-			       const struct zebra_dplane_info *zns,
-			       bool startup)
+			       bool is_cmd, bool startup)
 {
 	struct nlmsgerr *err = (struct nlmsgerr *)NLMSG_DATA(h);
 	int errnum = err->error;
@@ -834,7 +875,7 @@ static int netlink_parse_error(const struct nlsock *nl, struct nlmsghdr *h,
 	}
 
 	/* Deal with errors that occur because of races in link handling. */
-	if (zns->is_cmd
+	if (is_cmd
 	    && ((msg_type == RTM_DELROUTE
 		 && (-errnum == ENODEV || -errnum == ESRCH))
 		|| (msg_type == RTM_NEWROUTE
@@ -853,7 +894,7 @@ static int netlink_parse_error(const struct nlsock *nl, struct nlmsghdr *h,
 	 * do not log these as an error.
 	 */
 	if (msg_type == RTM_DELNEIGH
-	    || (zns->is_cmd && msg_type == RTM_NEWROUTE
+	    || (is_cmd && msg_type == RTM_NEWROUTE
 		&& (-errnum == ESRCH || -errnum == ENETUNREACH))) {
 		/*
 		 * This is known to happen in some situations, don't log as
@@ -925,8 +966,9 @@ int netlink_parse_info(int (*filter)(struct nlmsghdr *, ns_id_t, int),
 
 			/* Error handling. */
 			if (h->nlmsg_type == NLMSG_ERROR) {
-				int err = netlink_parse_error(nl, h, zns,
-							      startup);
+				int err = netlink_parse_error(
+					nl, h, zns->is_cmd, startup);
+
 				if (err == 1) {
 					if (!(h->nlmsg_flags & NLM_F_MULTI))
 						return 0;
@@ -938,8 +980,8 @@ int netlink_parse_info(int (*filter)(struct nlmsghdr *, ns_id_t, int),
 			/* OK we got netlink message. */
 			if (IS_ZEBRA_DEBUG_KERNEL)
 				zlog_debug(
-					"netlink_parse_info: %s type %s(%u), len=%d, seq=%u, pid=%u",
-					nl->name,
+					"%s: %s type %s(%u), len=%d, seq=%u, pid=%u",
+					__func__, nl->name,
 					nl_msg_type_to_str(h->nlmsg_type),
 					h->nlmsg_type, h->nlmsg_len,
 					h->nlmsg_seq, h->nlmsg_pid);
@@ -1141,7 +1183,8 @@ static int nl_batch_read_resp(struct nl_batch *bth)
 		}
 
 		if (h->nlmsg_type == NLMSG_ERROR) {
-			int err = netlink_parse_error(nl, h, bth->zns, 0);
+			int err = netlink_parse_error(nl, h, bth->zns->is_cmd,
+						      false);
 
 			if (err == -1)
 				dplane_ctx_set_status(