1/*
2 * Copyright (C) 2004-2006 Kay Sievers <kay.sievers@vrfy.org>
3 *
4 *	This program is free software; you can redistribute it and/or modify it
5 *	under the terms of the GNU General Public License as published by the
6 *	Free Software Foundation version 2 of the License.
7 *
8 *	This program is distributed in the hope that it will be useful, but
9 *	WITHOUT ANY WARRANTY; without even the implied warranty of
10 *	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
11 *	General Public License for more details.
12 *
13 *	You should have received a copy of the GNU General Public License along
14 *	with this program; if not, write to the Free Software Foundation, Inc.,
15 *	51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
16 *
17 */
18
19
20#include <stdlib.h>
21#include <stdio.h>
22#include <stddef.h>
23#include <unistd.h>
24#include <fcntl.h>
25#include <errno.h>
26#include <ctype.h>
27#include <sys/ioctl.h>
28#include <sys/socket.h>
29#include <net/if.h>
30#include <linux/sockios.h>
31
32#include "udev.h"
33#include "udev_rules.h"
34
35
36struct udevice *udev_device_init(struct udevice *udev)
37{
38	if (udev == NULL)
39		udev = malloc(sizeof(struct udevice));
40	if (udev == NULL)
41		return NULL;
42	memset(udev, 0x00, sizeof(struct udevice));
43
44	INIT_LIST_HEAD(&udev->symlink_list);
45	INIT_LIST_HEAD(&udev->run_list);
46	INIT_LIST_HEAD(&udev->env_list);
47
48	/* set sysfs device to local storage, can be overridden if needed */
49	udev->dev = &udev->dev_local;
50
51	/* default node permissions */
52	udev->mode = 0660;
53	strcpy(udev->owner, "root");
54	strcpy(udev->group, "root");
55
56	return udev;
57}
58
59void udev_device_cleanup(struct udevice *udev)
60{
61	name_list_cleanup(&udev->symlink_list);
62	name_list_cleanup(&udev->run_list);
63	name_list_cleanup(&udev->env_list);
64	free(udev);
65}
66
67dev_t udev_device_get_devt(struct udevice *udev)
68{
69	const char *attr;
70	unsigned int maj, min;
71
72	/* read it from sysfs  */
73	attr = sysfs_attr_get_value(udev->dev->devpath, "dev");
74	if (attr != NULL) {
75		if (sscanf(attr, "%u:%u", &maj, &min) == 2)
76			return makedev(maj, min);
77	}
78	return makedev(0, 0);
79}
80
81static int rename_netif(struct udevice *udev)
82{
83	int sk;
84	struct ifreq ifr;
85	int retval;
86
87	info("changing net interface name from '%s' to '%s'", udev->dev->kernel, udev->name);
88	if (udev->test_run)
89		return 0;
90
91	sk = socket(PF_INET, SOCK_DGRAM, 0);
92	if (sk < 0) {
93		err("error opening socket: %s", strerror(errno));
94		return -1;
95	}
96
97	memset(&ifr, 0x00, sizeof(struct ifreq));
98	strlcpy(ifr.ifr_name, udev->dev->kernel, IFNAMSIZ);
99	strlcpy(ifr.ifr_newname, udev->name, IFNAMSIZ);
100	retval = ioctl(sk, SIOCSIFNAME, &ifr);
101	if (retval != 0) {
102		int loop;
103
104		/* see if the destination interface name already exists */
105		if (errno != EEXIST) {
106			err("error changing netif name %s to %s: %s", ifr.ifr_name, ifr.ifr_newname, strerror(errno));
107			goto exit;
108		}
109
110		/* free our own name, another process may wait for us */
111		strlcpy(ifr.ifr_newname, udev->dev->kernel, IFNAMSIZ);
112		strlcat(ifr.ifr_newname, "_rename", IFNAMSIZ);
113		retval = ioctl(sk, SIOCSIFNAME, &ifr);
114		if (retval != 0) {
115			err("error changing netif name %s to %s: %s", ifr.ifr_name, ifr.ifr_newname, strerror(errno));
116			goto exit;
117		}
118
119		/* wait 30 seconds for our target to become available */
120		strlcpy(ifr.ifr_name, ifr.ifr_newname, IFNAMSIZ);
121		strlcpy(ifr.ifr_newname, udev->name, IFNAMSIZ);
122		loop = 30 * 20;
123		while (loop--) {
124			retval = ioctl(sk, SIOCSIFNAME, &ifr);
125			if (retval == 0)
126				break;
127
128			if (errno != EEXIST) {
129				err("error changing net interface name %s to %s: %s",
130				    ifr.ifr_name, ifr.ifr_newname, strerror(errno));
131				break;
132			}
133			dbg("wait for netif '%s' to become free, loop=%i", udev->name, (30 * 20) - loop);
134			usleep(1000 * 1000 / 20);
135		}
136	}
137
138exit:
139	close(sk);
140	return retval;
141}
142
143int udev_device_event(struct udev_rules *rules, struct udevice *udev)
144{
145	int retval = 0;
146
147	/* add device node */
148	if (major(udev->devt) != 0 &&
149	    (strcmp(udev->action, "add") == 0 || strcmp(udev->action, "change") == 0)) {
150		struct udevice *udev_old;
151
152		dbg("device node add '%s'", udev->dev->devpath);
153
154		udev_rules_get_name(rules, udev);
155		if (udev->ignore_device) {
156			info("device event will be ignored");
157			goto exit;
158		}
159		if (udev->name[0] == '\0') {
160			info("device node creation supressed");
161			goto exit;
162		}
163
164		/* read current database entry; cleanup, if it is known device */
165		udev_old = udev_device_init(NULL);
166		if (udev_old != NULL) {
167			udev_old->test_run = udev->test_run;
168			if (udev_db_get_device(udev_old, udev->dev->devpath) == 0) {
169				info("device '%s' already in database, cleanup", udev->dev->devpath);
170				udev_db_delete_device(udev_old);
171			} else {
172				udev_device_cleanup(udev_old);
173				udev_old = NULL;
174			}
175		}
176
177		/* create node */
178		retval = udev_node_add(udev);
179		if (retval != 0)
180			goto exit;
181
182		/* store in database */
183		udev_db_add_device(udev);
184
185		/* create, replace, delete symlinks according to priority */
186		udev_node_update_symlinks(udev, udev_old);
187
188		if (udev_old != NULL)
189			udev_device_cleanup(udev_old);
190		goto exit;
191	}
192
193	/* add netif */
194	if (strcmp(udev->dev->subsystem, "net") == 0 && strcmp(udev->action, "add") == 0) {
195		dbg("netif add '%s'", udev->dev->devpath);
196		udev_rules_get_name(rules, udev);
197		if (udev->ignore_device) {
198			info("device event will be ignored");
199			goto exit;
200		}
201		if (udev->name[0] == '\0') {
202			info("device renaming supressed");
203			goto exit;
204		}
205
206		/* look if we want to change the name of the netif */
207		if (strcmp(udev->name, udev->dev->kernel) != 0) {
208			char devpath[PATH_MAX];
209			char *pos;
210
211			retval = rename_netif(udev);
212			if (retval != 0)
213				goto exit;
214			info("renamed netif to '%s'", udev->name);
215
216			/* export old name */
217			setenv("INTERFACE_OLD", udev->dev->kernel, 1);
218
219			/* now change the devpath, because the kernel device name has changed */
220			strlcpy(devpath, udev->dev->devpath, sizeof(devpath));
221			pos = strrchr(devpath, '/');
222			if (pos != NULL) {
223				pos[1] = '\0';
224				strlcat(devpath, udev->name, sizeof(devpath));
225				sysfs_device_set_values(udev->dev, devpath, NULL, NULL);
226				setenv("DEVPATH", udev->dev->devpath, 1);
227				setenv("INTERFACE", udev->name, 1);
228				info("changed devpath to '%s'", udev->dev->devpath);
229			}
230		}
231		goto exit;
232	}
233
234	/* remove device node */
235	if (major(udev->devt) != 0 && strcmp(udev->action, "remove") == 0) {
236		struct name_entry *name_loop;
237
238		/* import database entry, and delete it */
239		if (udev_db_get_device(udev, udev->dev->devpath) == 0) {
240			udev_db_delete_device(udev);
241			if (udev->ignore_remove) {
242				info("ignore_remove for '%s'", udev->name);
243				goto exit;
244			}
245			/* restore stored persistent data */
246			list_for_each_entry(name_loop, &udev->env_list, node)
247				putenv(name_loop->name);
248		} else {
249			dbg("'%s' not found in database, using kernel name '%s'",
250			    udev->dev->devpath, udev->dev->kernel);
251			strlcpy(udev->name, udev->dev->kernel, sizeof(udev->name));
252		}
253
254		udev_rules_get_run(rules, udev);
255		if (udev->ignore_device) {
256			info("device event will be ignored");
257			goto exit;
258		}
259
260		/* remove the node */
261		retval = udev_node_remove(udev);
262
263		/* delete or restore symlinks according to priority */
264		udev_node_update_symlinks(udev, NULL);
265		goto exit;
266	}
267
268	/* default devices */
269	udev_rules_get_run(rules, udev);
270	if (udev->ignore_device)
271		info("device event will be ignored");
272
273exit:
274	return retval;
275}
276