1/*
2 * Copyright (C) 2011 matt mooney <mfm@muteddisk.com>
3 *               2005-2007 Takahiro Hirofuchi
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 as published by
7 * the Free Software Foundation, either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
17 */
18
19#include <sys/types.h>
20#include <sys/stat.h>
21#include <fcntl.h>
22
23#include <errno.h>
24#include <unistd.h>
25
26#include <libudev.h>
27
28#include "usbip_common.h"
29#include "usbip_host_driver.h"
30#include "list.h"
31#include "sysfs_utils.h"
32
33#undef  PROGNAME
34#define PROGNAME "libusbip"
35
36struct usbip_host_driver *host_driver;
37struct udev *udev_context;
38
39static int32_t read_attr_usbip_status(struct usbip_usb_device *udev)
40{
41	char status_attr_path[SYSFS_PATH_MAX];
42	int fd;
43	int length;
44	char status;
45	int value = 0;
46
47	snprintf(status_attr_path, SYSFS_PATH_MAX, "%s/usbip_status",
48		 udev->path);
49
50	fd = open(status_attr_path, O_RDONLY);
51	if (fd < 0) {
52		err("error opening attribute %s", status_attr_path);
53		return -1;
54	}
55
56	length = read(fd, &status, 1);
57	if (length < 0) {
58		err("error reading attribute %s", status_attr_path);
59		close(fd);
60		return -1;
61	}
62
63	value = atoi(&status);
64
65	return value;
66}
67
68static
69struct usbip_exported_device *usbip_exported_device_new(const char *sdevpath)
70{
71	struct usbip_exported_device *edev = NULL;
72	struct usbip_exported_device *edev_old;
73	size_t size;
74	int i;
75
76	edev = calloc(1, sizeof(struct usbip_exported_device));
77
78	edev->sudev = udev_device_new_from_syspath(udev_context, sdevpath);
79	if (!edev->sudev) {
80		err("udev_device_new_from_syspath: %s", sdevpath);
81		goto err;
82	}
83
84	read_usb_device(edev->sudev, &edev->udev);
85
86	edev->status = read_attr_usbip_status(&edev->udev);
87	if (edev->status < 0)
88		goto err;
89
90	/* reallocate buffer to include usb interface data */
91	size = sizeof(struct usbip_exported_device) +
92		edev->udev.bNumInterfaces * sizeof(struct usbip_usb_interface);
93
94	edev_old = edev;
95	edev = realloc(edev, size);
96	if (!edev) {
97		edev = edev_old;
98		dbg("realloc failed");
99		goto err;
100	}
101
102	for (i = 0; i < edev->udev.bNumInterfaces; i++)
103		read_usb_interface(&edev->udev, i, &edev->uinf[i]);
104
105	return edev;
106err:
107	if (edev->sudev)
108		udev_device_unref(edev->sudev);
109	if (edev)
110		free(edev);
111
112	return NULL;
113}
114
115static int refresh_exported_devices(void)
116{
117	struct usbip_exported_device *edev;
118	struct udev_enumerate *enumerate;
119	struct udev_list_entry *devices, *dev_list_entry;
120	struct udev_device *dev;
121	const char *path;
122	const char *driver;
123
124	enumerate = udev_enumerate_new(udev_context);
125	udev_enumerate_add_match_subsystem(enumerate, "usb");
126	udev_enumerate_scan_devices(enumerate);
127
128	devices = udev_enumerate_get_list_entry(enumerate);
129
130	udev_list_entry_foreach(dev_list_entry, devices) {
131		path = udev_list_entry_get_name(dev_list_entry);
132		dev = udev_device_new_from_syspath(udev_context, path);
133		if (dev == NULL)
134			continue;
135
136		/* Check whether device uses usbip-host driver. */
137		driver = udev_device_get_driver(dev);
138		if (driver != NULL && !strcmp(driver, USBIP_HOST_DRV_NAME)) {
139			edev = usbip_exported_device_new(path);
140			if (!edev) {
141				dbg("usbip_exported_device_new failed");
142				continue;
143			}
144
145			list_add(&edev->node, &host_driver->edev_list);
146			host_driver->ndevs++;
147		}
148	}
149
150	return 0;
151}
152
153static void usbip_exported_device_destroy(void)
154{
155	struct list_head *i, *tmp;
156	struct usbip_exported_device *edev;
157
158	list_for_each_safe(i, tmp, &host_driver->edev_list) {
159		edev = list_entry(i, struct usbip_exported_device, node);
160		list_del(i);
161		free(edev);
162	}
163}
164
165int usbip_host_driver_open(void)
166{
167	int rc;
168
169	udev_context = udev_new();
170	if (!udev_context) {
171		err("udev_new failed");
172		return -1;
173	}
174
175	host_driver = calloc(1, sizeof(*host_driver));
176
177	host_driver->ndevs = 0;
178	INIT_LIST_HEAD(&host_driver->edev_list);
179
180	rc = refresh_exported_devices();
181	if (rc < 0)
182		goto err_free_host_driver;
183
184	return 0;
185
186err_free_host_driver:
187	free(host_driver);
188	host_driver = NULL;
189
190	udev_unref(udev_context);
191
192	return -1;
193}
194
195void usbip_host_driver_close(void)
196{
197	if (!host_driver)
198		return;
199
200	usbip_exported_device_destroy();
201
202	free(host_driver);
203	host_driver = NULL;
204
205	udev_unref(udev_context);
206}
207
208int usbip_host_refresh_device_list(void)
209{
210	int rc;
211
212	usbip_exported_device_destroy();
213
214	host_driver->ndevs = 0;
215	INIT_LIST_HEAD(&host_driver->edev_list);
216
217	rc = refresh_exported_devices();
218	if (rc < 0)
219		return -1;
220
221	return 0;
222}
223
224int usbip_host_export_device(struct usbip_exported_device *edev, int sockfd)
225{
226	char attr_name[] = "usbip_sockfd";
227	char sockfd_attr_path[SYSFS_PATH_MAX];
228	char sockfd_buff[30];
229	int ret;
230
231	if (edev->status != SDEV_ST_AVAILABLE) {
232		dbg("device not available: %s", edev->udev.busid);
233		switch (edev->status) {
234		case SDEV_ST_ERROR:
235			dbg("status SDEV_ST_ERROR");
236			break;
237		case SDEV_ST_USED:
238			dbg("status SDEV_ST_USED");
239			break;
240		default:
241			dbg("status unknown: 0x%x", edev->status);
242		}
243		return -1;
244	}
245
246	/* only the first interface is true */
247	snprintf(sockfd_attr_path, sizeof(sockfd_attr_path), "%s/%s",
248		 edev->udev.path, attr_name);
249
250	snprintf(sockfd_buff, sizeof(sockfd_buff), "%d\n", sockfd);
251
252	ret = write_sysfs_attribute(sockfd_attr_path, sockfd_buff,
253				    strlen(sockfd_buff));
254	if (ret < 0) {
255		err("write_sysfs_attribute failed: sockfd %s to %s",
256		    sockfd_buff, sockfd_attr_path);
257		return ret;
258	}
259
260	info("connect: %s", edev->udev.busid);
261
262	return ret;
263}
264
265struct usbip_exported_device *usbip_host_get_device(int num)
266{
267	struct list_head *i;
268	struct usbip_exported_device *edev;
269	int cnt = 0;
270
271	list_for_each(i, &host_driver->edev_list) {
272		edev = list_entry(i, struct usbip_exported_device, node);
273		if (num == cnt)
274			return edev;
275		else
276			cnt++;
277	}
278
279	return NULL;
280}
281