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[project/netifd.git] / interface-event.c
1 /*
2  * netifd - network interface daemon
3  * Copyright (C) 2012 Felix Fietkau <nbd@openwrt.org>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2
7  * as published by the Free Software Foundation
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  */
14 #include <stdio.h>
15 #include <stdlib.h>
16 #include <string.h>
17 #include <unistd.h>
18
19 #include <libubox/uloop.h>
20
21 #include "netifd.h"
22 #include "interface.h"
23 #include "ubus.h"
24
25 char *hotplug_cmd_path = DEFAULT_HOTPLUG_PATH;
26 static struct interface *current;
27 static enum interface_event current_ev;
28 static struct list_head pending = LIST_HEAD_INIT(pending);
29
30 static void task_complete(struct uloop_process *proc, int ret);
31 static struct uloop_process task = {
32         .cb = task_complete,
33 };
34
35 static void
36 run_cmd(const char *ifname, const char *device, bool up)
37 {
38         char *argv[3];
39         int pid;
40
41         pid = fork();
42         if (pid < 0)
43                 return task_complete(NULL, -1);
44
45         if (pid > 0) {
46                 task.pid = pid;
47                 uloop_process_add(&task);
48                 return;
49         }
50
51         setenv("ACTION", up ? "ifup" : "ifdown", 1);
52         setenv("INTERFACE", ifname, 1);
53         if (device)
54                 setenv("DEVICE", device, 1);
55         argv[0] = hotplug_cmd_path;
56         argv[1] = "iface";
57         argv[2] = NULL;
58         execvp(argv[0], argv);
59         exit(127);
60 }
61
62 static void
63 call_hotplug(void)
64 {
65         const char *device = NULL;
66         if (list_empty(&pending))
67                 return;
68
69         current = list_first_entry(&pending, struct interface, hotplug_list);
70         current_ev = current->hotplug_ev;
71         list_del_init(&current->hotplug_list);
72
73         if (current_ev == IFEV_UP && current->l3_dev.dev)
74                 device = current->l3_dev.dev->ifname;
75
76         D(SYSTEM, "Call hotplug handler for interface '%s' (%s)\n", current->name, device ? device : "none");
77         run_cmd(current->name, device, current_ev == IFEV_UP);
78 }
79
80 static void
81 task_complete(struct uloop_process *proc, int ret)
82 {
83         if (current)
84                 D(SYSTEM, "Complete hotplug handler for interface '%s'\n", current->name);
85         current = NULL;
86         call_hotplug();
87 }
88
89 /*
90  * Queue an interface for an up/down event.
91  * An interface can only have one event in the queue and one
92  * event waiting for completion.
93  * When queueing an event that is the same as the one waiting for
94  * completion, remove the interface from the queue
95  */
96 static void
97 interface_queue_event(struct interface *iface, enum interface_event ev)
98 {
99         enum interface_event last_ev;
100
101         D(SYSTEM, "Queue hotplug handler for interface '%s'\n", iface->name);
102         netifd_ubus_interface_event(iface, ev == IFEV_UP);
103         if (current == iface)
104                 last_ev = current_ev;
105         else
106                 last_ev = iface->hotplug_ev;
107
108         iface->hotplug_ev = ev;
109         if (last_ev == ev && !list_empty(&iface->hotplug_list))
110                 list_del_init(&iface->hotplug_list);
111         else if (last_ev != ev && list_empty(&iface->hotplug_list))
112                 list_add(&iface->hotplug_list, &pending);
113
114         if (!task.pending && !current)
115                 call_hotplug();
116 }
117
118 static void
119 interface_dequeue_event(struct interface *iface)
120 {
121         if (iface == current)
122                 current = NULL;
123
124         if (!list_empty(&iface->hotplug_list))
125                 list_del_init(&iface->hotplug_list);
126 }
127
128 static void interface_event_cb(struct interface_user *dep, struct interface *iface,
129                                enum interface_event ev)
130 {
131         switch (ev) {
132                 case IFEV_UP:
133                 case IFEV_DOWN:
134                         interface_queue_event(iface, ev);
135                         break;
136                 case IFEV_FREE:
137                 case IFEV_RELOAD:
138                         interface_dequeue_event(iface);
139                         break;
140         }
141 }
142
143 static struct interface_user event_user = {
144         .cb = interface_event_cb
145 };
146
147 static void __init interface_event_init(void)
148 {
149         interface_add_user(&event_user, NULL);
150 }