add rudimentary protocol handling

6 files changed, 166 insertions, 50 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 262ee3b..496e9d5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -9,5 +9,5 @@ IF(DEBUG)
   ADD_DEFINITIONS(-DDEBUG -O0)
 ENDIF()
 
-ADD_EXECUTABLE(netifd main.c interface.c config.c device.c bridge.c vlan.c ubus.c system-dummy.c)
+ADD_EXECUTABLE(netifd main.c interface.c proto.c config.c device.c bridge.c vlan.c ubus.c system-dummy.c)
 TARGET_LINK_LIBRARIES(netifd ubox ubus uci)
diff --git a/interface.c b/interface.c
index 0aa0b0d..78cfe12 100644
--- a/interface.c
+++ b/interface.c
@@ -3,9 +3,10 @@
 #include <stdio.h>
 
 #include "netifd.h"
+#include "proto.h"
 #include "ubus.h"
 
-LIST_HEAD(interfaces);
+static LIST_HEAD(interfaces);
 
 static void
 clear_interface_errors(struct interface *iface)
@@ -52,42 +53,51 @@ void interface_add_error(struct interface *iface, const char *subsystem,
 	error->data[n_data] = NULL;
 }
 
-static int
+static void
 interface_event(struct interface *iface, enum interface_event ev)
 {
-	if (!iface->state || !iface->state->event)
-		return 0;
-
-	return iface->state->event(iface->state, ev);
+	/* TODO */
 }
 
-static void
+static int
 __set_interface_up(struct interface *iface)
 {
-	if (iface->up)
-		return;
+	int ret;
 
-	if (claim_device(iface->main_dev.dev) < 0)
-		return;
+	if (iface->state != IFS_DOWN)
+		return 0;
 
-	if (interface_event(iface, IFEV_UP) < 0) {
-		release_device(iface->main_dev.dev);
-		return;
-	}
+	ret = claim_device(iface->main_dev.dev);
+	if (ret)
+		goto out;
+
+	iface->state = IFS_SETUP;
+	ret = iface->proto->handler(iface->proto, PROTO_CMD_SETUP, false);
+	if (ret)
+		goto release;
 
-	iface->up = true;
+	return 0;
+
+release:
+	release_device(iface->main_dev.dev);
+out:
+	iface->state = IFS_DOWN;
+	return ret;
 }
 
 static void
-__set_interface_down(struct interface *iface)
+__set_interface_down(struct interface *iface, bool force)
 {
 	clear_interface_errors(iface);
 
-	if (!iface->up)
+	if (iface->state == IFS_DOWN ||
+		iface->state == IFS_TEARDOWN)
 		return;
 
-	iface->up = false;
+	iface->state = IFS_TEARDOWN;
 	interface_event(iface, IFEV_DOWN);
+
+	iface->proto->handler(iface->proto, PROTO_CMD_TEARDOWN, force);
 	release_device(iface->main_dev.dev);
 }
 
@@ -116,9 +126,44 @@ interface_cb(struct device_user *dep, enum device_event ev)
 
 	if (new_state) {
 		if (iface->autostart)
-			__set_interface_up(iface);
+			set_interface_up(iface);
 	} else
-		__set_interface_down(iface);
+		__set_interface_down(iface, true);
+}
+
+static void
+interface_proto_cb(struct interface_proto_state *state, enum interface_proto_event ev)
+{
+	struct interface *iface = state->iface;
+
+	switch (ev) {
+	case IFPEV_UP:
+		if (iface->state != IFS_SETUP)
+			return;
+
+		iface->state = IFS_UP;
+		interface_event(iface, IFEV_UP);
+		break;
+	case IFPEV_DOWN:
+		iface->state = IFS_DOWN;
+		break;
+	}
+}
+
+void interface_set_proto_state(struct interface *iface, struct interface_proto_state *state)
+{
+	if (iface->proto) {
+		iface->proto->handler(iface->proto, PROTO_CMD_TEARDOWN, true);
+		iface->proto->free(iface->proto);
+		iface->proto = NULL;
+	}
+	iface->state = IFS_DOWN;
+	iface->proto = state;
+	if (!state)
+		return;
+
+	state->proto_event = interface_proto_cb;
+	state->iface = iface;
 }
 
 struct interface *
@@ -131,6 +176,13 @@ alloc_interface(const char *name)
 		return iface;
 
 	iface = calloc(1, sizeof(*iface));
+
+	interface_set_proto_state(iface, get_default_proto());
+	if (!iface->proto) {
+		free(iface);
+		return NULL;
+	}
+
 	iface->main_dev.cb = interface_cb;
 	iface->l3_iface = &iface->main_dev;
 	strncpy(iface->name, name, sizeof(iface->name) - 1);
@@ -147,8 +199,8 @@ free_interface(struct interface *iface)
 {
 	netifd_ubus_remove_interface(iface);
 	list_del(&iface->list);
-	if (iface->state && iface->state->free)
-		iface->state->free(iface->state);
+	if (iface->proto->free)
+		iface->proto->free(iface->proto);
 	free(iface);
 }
 
@@ -203,18 +255,17 @@ set_interface_up(struct interface *iface)
 		return -1;
 	}
 
-	if (iface->up)
-		return -1;
+	if (iface->state != IFS_DOWN)
+		return 0;
 
-	__set_interface_up(iface);
-	return 0;
+	return __set_interface_up(iface);
 }
 
 int
 set_interface_down(struct interface *iface)
 {
 	iface->autostart = false;
-	__set_interface_down(iface);
+	__set_interface_down(iface, false);
 
 	return 0;
 }
diff --git a/interface.h b/interface.h
index dd72389..87a7cb3 100644
--- a/interface.h
+++ b/interface.h
@@ -2,31 +2,18 @@
 #define __NETIFD_INTERFACE_H
 
 struct interface;
-struct interface_proto;
 struct interface_proto_state;
 
-extern struct list_head interfaces;
-
 enum interface_event {
 	IFEV_UP,
 	IFEV_DOWN,
 };
 
-enum interface_proto_event {
-	PROTO_UP,
-	PROTO_DOWN,
-};
-
-struct interface_proto_state {
-	struct interface *iface;
-	const struct interface_proto *proto;
-
-	/* filled in by the protocol user */
-	int (*proto_event)(struct interface_proto_state *, enum interface_proto_event ev);
-
-	/* filled in by the protocol handler */
-	int (*event)(struct interface_proto_state *, enum interface_event ev);
-	void (*free)(struct interface_proto_state *);
+enum interface_state {
+	IFS_SETUP,
+	IFS_UP,
+	IFS_TEARDOWN,
+	IFS_DOWN,
 };
 
 struct interface_error {
@@ -45,10 +32,11 @@ struct interface {
 
 	char name[IFNAMSIZ];
 
-	bool up;
 	bool active;
 	bool autostart;
 
+	enum interface_state state;
+
 	/* main interface that the interface is bound to */
 	struct device_user main_dev;
 
@@ -56,7 +44,7 @@ struct interface {
 	struct device_user *l3_iface;
 
 	/* primary protocol state */
-	struct interface_proto_state *state;
+	struct interface_proto_state *proto;
 
 	/* errors/warnings while trying to bring up the interface */
 	struct list_head errors;
diff --git a/proto.c b/proto.c
new file mode 100644
index 0000000..a345b35
--- /dev/null
+++ b/proto.c
@@ -0,0 +1,42 @@
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+#include "netifd.h"
+#include "proto.h"
+
+static void
+default_proto_free(struct interface_proto_state *proto)
+{
+	free(proto);
+}
+
+static int
+default_proto_handler(struct interface_proto_state *proto,
+		      enum interface_proto_cmd cmd, bool force)
+{
+	enum interface_event ev;
+
+	switch(cmd) {
+	case PROTO_CMD_SETUP:
+		ev = IFEV_UP;
+		break;
+	case PROTO_CMD_TEARDOWN:
+		ev = IFEV_DOWN;
+		break;
+	default:
+		return -EINVAL;
+	}
+	proto->proto_event(proto, ev);
+	return 0;
+}
+
+struct interface_proto_state *get_default_proto(void)
+{
+	struct interface_proto_state *proto;
+
+	proto = calloc(1, sizeof(*proto));
+	proto->handler = default_proto_handler;
+	proto->free = default_proto_free;
+	return proto;
+}
diff --git a/proto.h b/proto.h
new file mode 100644
index 0000000..92cef01
--- /dev/null
+++ b/proto.h
@@ -0,0 +1,29 @@
+#ifndef __NETIFD_PROTO_H
+#define __NETIFD_PROTO_H
+
+struct interface_proto_state;
+
+enum interface_proto_event {
+	IFPEV_UP,
+	IFPEV_DOWN,
+};
+
+enum interface_proto_cmd {
+	PROTO_CMD_SETUP,
+	PROTO_CMD_TEARDOWN,
+};
+
+struct interface_proto_state {
+	struct interface *iface;
+
+	/* filled in by the protocol user */
+	void (*proto_event)(struct interface_proto_state *, enum interface_proto_event ev);
+
+	/* filled in by the protocol handler */
+	int (*handler)(struct interface_proto_state *, enum interface_proto_cmd cmd, bool force);
+	void (*free)(struct interface_proto_state *);
+};
+
+struct interface_proto_state *get_default_proto(void);
+
+#endif
diff --git a/ubus.c b/ubus.c
index 159d5f5..e5df1fb 100644
--- a/ubus.c
+++ b/ubus.c
@@ -138,12 +138,18 @@ static int netifd_handle_status(struct ubus_context *ctx, struct ubus_object *ob
 				struct ubus_request_data *req, const char *method,
 				struct blob_attr *msg)
 {
+	static const char *iface_state[] = {
+		[IFS_SETUP] = "setup",
+		[IFS_UP] = "up",
+		[IFS_TEARDOWN] = "teardown",
+		[IFS_DOWN] = "down",
+	};
 	struct interface *iface;
 
 	iface = container_of(obj, struct interface, ubus);
 
 	blob_buf_init(&b, 0);
-	blobmsg_add_u8(&b, "up", iface->up);
+	blobmsg_add_string(&b, "state", iface_state[iface->state]);
 	blobmsg_add_u8(&b, "active", iface->active);
 	blobmsg_add_u8(&b, "autostart", iface->autostart);
 	if (iface->main_dev.dev) {