summaryrefslogtreecommitdiffhomepage
path: root/interface-event.c
blob: cfbc15c2bd5bcf3008a798949b08804e79e2e799 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
/*
 * netifd - network interface daemon
 * Copyright (C) 2012 Felix Fietkau <nbd@openwrt.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2
 * as published by the Free Software Foundation
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <libubox/uloop.h>

#include "netifd.h"
#include "interface.h"
#include "ubus.h"

char *hotplug_cmd_path = DEFAULT_HOTPLUG_PATH;
static struct interface *current;
static enum interface_event current_ev;
static struct list_head pending = LIST_HEAD_INIT(pending);

static void task_complete(struct uloop_process *proc, int ret);
static struct uloop_process task = {
	.cb = task_complete,
};
static const char * const eventnames[] = {"ifdown", "ifup", "ifupdate"};

static void
run_cmd(const char *ifname, const char *device, enum interface_event event,
		enum interface_update_flags updated)
{
	char *argv[3];
	int pid;

	pid = fork();
	if (pid < 0)
		return task_complete(NULL, -1);

	if (pid > 0) {
		task.pid = pid;
		uloop_process_add(&task);
		return;
	}

	setenv("ACTION", eventnames[event], 1);
	setenv("INTERFACE", ifname, 1);
	if (device)
		setenv("DEVICE", device, 1);

	if (event == IFEV_UPDATE) {
		if (updated & IUF_ADDRESS)
			setenv("IFUPDATE_ADDRESSES", "1", 1);
		if (updated & IUF_ROUTE)
			setenv("IFUPDATE_ROUTES", "1", 1);
		if (updated & IUF_PREFIX)
			setenv("IFUPDATE_PREFIXES", "1", 1);
		if (updated & IUF_DATA)
			setenv("IFUPDATE_DATA", "1", 1);
	}

	argv[0] = hotplug_cmd_path;
	argv[1] = "iface";
	argv[2] = NULL;
	execvp(argv[0], argv);
	exit(127);
}

static void
call_hotplug(void)
{
	const char *device = NULL;
	if (list_empty(&pending))
		return;

	current = list_first_entry(&pending, struct interface, hotplug_list);
	current_ev = current->hotplug_ev;
	list_del_init(&current->hotplug_list);

	if ((current_ev == IFEV_UP || current_ev == IFEV_UPDATE) && current->l3_dev.dev)
		device = current->l3_dev.dev->ifname;

	D(SYSTEM, "Call hotplug handler for interface '%s', event '%s' (%s)\n",
	current->name, eventnames[current_ev], device ? device : "none");
	run_cmd(current->name, device, current_ev, current->updated);
}

static void
task_complete(struct uloop_process *proc, int ret)
{
	if (current)
		D(SYSTEM, "Complete hotplug handler for interface '%s'\n", current->name);
	current = NULL;
	call_hotplug();
}

/*
 * Queue an interface for an up/down event.
 * An interface can only have one event in the queue and one
 * event waiting for completion.
 * When queueing an event that is the same as the one waiting for
 * completion, remove the interface from the queue
 */
static void
interface_queue_event(struct interface *iface, enum interface_event ev)
{
	D(SYSTEM, "Queue hotplug handler for interface '%s', event '%s'\n",
			iface->name, eventnames[ev]);
	if (ev == IFEV_UP || ev == IFEV_DOWN)
		netifd_ubus_interface_event(iface, ev == IFEV_UP);

	netifd_ubus_interface_notify(iface, ev != IFEV_DOWN);

	if (current == iface) {
		/* an event for iface is being processed */
		if (!list_empty(&iface->hotplug_list)) {
			/* an additional event for iface is pending   */
			/* overwrite pending event if it differs from */
			/* an update                                  */
			if (ev != IFEV_UPDATE)
				iface->hotplug_ev = ev;
		}
		else {
			/* no additional event for iface is pending */
			if (ev != current_ev || ev == IFEV_UPDATE) {
				/* only add the interface to the pending list if
				 * the event is different from the one being
				 * handled or if it is an update */
				iface->hotplug_ev = ev;
				/* Handle hotplug calls FIFO */
				list_add_tail(&iface->hotplug_list, &pending);
			}
		}
	}
	else {
		/* currently not handling an event or handling an event
		 * for another interface */
		if (!list_empty(&iface->hotplug_list)) {
			/* an event for iface is pending */
			if (!(iface->hotplug_ev == IFEV_UP &&
				ev == IFEV_UPDATE)) {
				/* overwrite pending event, unless the incoming
				 * event is an ifupdate while the pending one
				 * is an ifup */
				iface->hotplug_ev = ev;
			}
		}
		else {
			/* an event for the interface is not yet pending,
			 * queue it */
			iface->hotplug_ev = ev;
			/* Handle hotplug calls FIFO */
			list_add_tail(&iface->hotplug_list, &pending);
		}
	}

	if (!task.pending && !current)
		call_hotplug();
}

static void
interface_dequeue_event(struct interface *iface)
{
	if (iface == current)
		current = NULL;

	if (!list_empty(&iface->hotplug_list))
		list_del_init(&iface->hotplug_list);
}

static void interface_event_cb(struct interface_user *dep, struct interface *iface,
			       enum interface_event ev)
{
	switch (ev) {
		case IFEV_UP:
		case IFEV_UPDATE:
		case IFEV_DOWN:
			interface_queue_event(iface, ev);
			break;
		case IFEV_FREE:
		case IFEV_RELOAD:
			interface_dequeue_event(iface);
			break;
	}
}

static struct interface_user event_user = {
	.cb = interface_event_cb
};

static void __init interface_event_init(void)
{
	interface_add_user(&event_user, NULL);
}