Initial import

1 files changed, 343 insertions, 0 deletions

diff --git a/bridge.c b/bridge.c
new file mode 100644
index 0000000..2aa0e68
--- /dev/null
+++ b/bridge.c
@@ -0,0 +1,343 @@
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <assert.h>
+#include <errno.h>
+
+#include "netifd.h"
+#include "system.h"
+
+struct bridge_state {
+	struct device dev;
+	device_state_cb set_state;
+
+	bool active;
+
+	struct list_head members;
+	int n_present;
+};
+
+struct bridge_member {
+	struct list_head list;
+	struct bridge_state *bst;
+	struct device_user dev;
+	bool present;
+};
+
+static int
+bridge_disable_member(struct bridge_member *bm)
+{
+	struct bridge_state *bst = bm->bst;
+
+	if (!bm->present)
+		return 0;
+
+	system_bridge_delif(&bst->dev, bm->dev.dev);
+	release_device(bm->dev.dev);
+
+	return 0;
+}
+
+static int
+bridge_enable_member(struct bridge_member *bm)
+{
+	struct bridge_state *bst = bm->bst;
+	int ret;
+
+	if (!bm->present)
+		return 0;
+
+	ret = claim_device(bm->dev.dev);
+	if (ret < 0)
+		goto error;
+
+	ret = system_bridge_addif(&bst->dev, bm->dev.dev);
+	if (ret < 0)
+		goto error;
+
+	return 0;
+
+error:
+	bm->present = false;
+	bst->n_present--;
+	return ret;
+}
+
+static void
+bridge_member_cb(struct device_user *dev, enum device_event ev)
+{
+	struct bridge_member *bm = container_of(dev, struct bridge_member, dev);
+	struct bridge_state *bst = bm->bst;
+
+	switch (ev) {
+	case DEV_EVENT_ADD:
+		assert(!bm->present);
+
+		bm->present = true;
+		bst->n_present++;
+
+		if (bst->dev.active)
+			bridge_enable_member(bm);
+		else if (bst->n_present == 1)
+			set_device_present(&bst->dev, true);
+
+		break;
+	case DEV_EVENT_REMOVE:
+		if (!bm->present)
+			return;
+
+		if (bst->dev.active)
+			bridge_disable_member(bm);
+
+		bm->present = false;
+		bm->bst->n_present--;
+		if (bst->n_present == 0)
+			set_device_present(&bst->dev, false);
+
+		break;
+	default:
+		return;
+	}
+}
+
+static int
+bridge_set_down(struct bridge_state *bst)
+{
+	struct bridge_member *bm;
+
+	bst->set_state(&bst->dev, false);
+
+	list_for_each_entry(bm, &bst->members, list)
+		bridge_disable_member(bm);
+
+	system_bridge_delbr(&bst->dev);
+
+	return 0;
+}
+
+static int
+bridge_set_up(struct bridge_state *bst)
+{
+	struct bridge_member *bm;
+	int ret;
+
+	if (!bst->n_present)
+		return -ENOENT;
+
+	ret = system_bridge_addbr(&bst->dev);
+	if (ret < 0)
+		goto out;
+
+	list_for_each_entry(bm, &bst->members, list)
+		bridge_enable_member(bm);
+
+	if (!bst->n_present) {
+		/* initialization of all member interfaces failed */
+		system_bridge_delbr(&bst->dev);
+		set_device_present(&bst->dev, false);
+		return -ENOENT;
+	}
+
+	ret = bst->set_state(&bst->dev, true);
+	if (ret < 0)
+		bridge_set_down(bst);
+
+out:
+	return ret;
+}
+
+static int
+bridge_set_state(struct device *dev, bool up)
+{
+	struct bridge_state *bst;
+
+	bst = container_of(dev, struct bridge_state, dev);
+
+	if (up)
+		return bridge_set_up(bst);
+	else
+		return bridge_set_down(bst);
+}
+
+static struct bridge_member *
+bridge_create_member(struct bridge_state *bst, struct device *dev)
+{
+	struct bridge_member *bm;
+
+	bm = calloc(1, sizeof(*bm));
+	bm->bst = bst;
+	bm->dev.cb = bridge_member_cb;
+	add_device_user(&bm->dev, dev);
+
+	list_add(&bm->list, &bst->members);
+
+	if (bst->dev.active)
+		bridge_enable_member(bm);
+
+	return bm;
+}
+
+static void
+bridge_free_member(struct bridge_member *bm)
+{
+	if (bm->present) {
+		bridge_member_cb(&bm->dev, DEV_EVENT_REMOVE);
+		bm->bst->n_present--;
+		if (bm->bst->dev.active)
+			bridge_disable_member(bm);
+	}
+
+	list_del(&bm->list);
+	remove_device_user(&bm->dev);
+	free(bm);
+}
+
+static void
+bridge_add_member(struct bridge_state *bst, const char *name)
+{
+	struct device *dev;
+
+	dev = get_device(name, true);
+	if (!dev)
+		return;
+
+	bridge_create_member(bst, dev);
+}
+
+static int
+bridge_hotplug_add(struct device *dev, struct device *member)
+{
+	struct bridge_state *bst = container_of(dev, struct bridge_state, dev);
+
+	bridge_create_member(bst, member);
+
+	return 0;
+}
+
+static int
+bridge_hotplug_del(struct device *dev, struct device *member)
+{
+	struct bridge_state *bst = container_of(dev, struct bridge_state, dev);
+	struct bridge_member *bm;
+
+	list_for_each_entry(bm, &bst->members, list) {
+		if (bm->dev.dev != member)
+			continue;
+
+		bridge_free_member(bm);
+		return 0;
+	}
+
+	return -ENOENT;
+}
+
+static const struct device_hotplug_ops bridge_ops = {
+	.add = bridge_hotplug_add,
+	.del = bridge_hotplug_del
+};
+
+static void
+bridge_parse_config(struct bridge_state *bst, struct uci_section *s)
+{
+	struct uci_element *e;
+	struct uci_option *o;
+	char buf[IFNAMSIZ + 1];
+	char *p, *end;
+	int len;
+
+	o = uci_lookup_option(uci_ctx, s, "ifname");
+	if (!o)
+		return;
+
+	if (o->type == UCI_TYPE_LIST) {
+		uci_foreach_element(&o->v.list, e)
+			bridge_add_member(bst, e->name);
+	} else {
+		p = o->v.string;
+		do {
+			if (!*p)
+				break;
+
+			if (*p == ' ')
+				continue;
+
+			end = strchr(p, ' ');
+			if (!end) {
+				bridge_add_member(bst, p);
+				break;
+			}
+
+			len = end - p;
+			if (len <= IFNAMSIZ) {
+				memcpy(buf, p, len);
+				buf[len] = 0;
+				bridge_add_member(bst, buf);
+			}
+			p = end;
+		} while (p++);
+	}
+}
+
+static void
+bridge_free(struct device *dev)
+{
+	struct bridge_state *bst;
+	struct bridge_member *bm;
+
+	bst = container_of(dev, struct bridge_state, dev);
+	while (!list_empty(&bst->members)) {
+		bm = list_first_entry(&bst->members, struct bridge_member, list);
+		bridge_free_member(bm);
+	}
+	free(bst);
+}
+
+struct device *
+bridge_create(const char *name, struct uci_section *s)
+{
+	static const struct device_type bridge_type = {
+		.name = "Bridge",
+		.free = bridge_free,
+	};
+	struct bridge_state *bst;
+	struct device *dev;
+
+	dev = get_device(name, false);
+	if (dev)
+		return NULL;
+
+	bst = calloc(1, sizeof(*bst));
+	if (!bst)
+		return NULL;
+
+	init_device(&bst->dev, &bridge_type, name);
+
+	bst->set_state = bst->dev.set_state;
+	bst->dev.set_state = bridge_set_state;
+
+	bst->dev.hotplug_ops = &bridge_ops;
+
+	INIT_LIST_HEAD(&bst->members);
+
+	if (s)
+		bridge_parse_config(bst, s);
+
+	return &bst->dev;
+}
+
+int
+interface_attach_bridge(struct interface *iface, struct uci_section *s)
+{
+	struct device *dev;
+	char brname[IFNAMSIZ];
+
+	snprintf(brname, IFNAMSIZ - 1, "br-%s", iface->name);
+	brname[IFNAMSIZ - 1] = 0;
+
+	dev = bridge_create(brname, s);
+	if (!dev)
+		return -1;
+
+	add_device_user(&iface->main_dev, dev);
+	return 0;
+}