1/*
  2 * Copyright (C) 2015-2016 Samsung Electronics
  3 *               Igor Kotrasinski <i.kotrasinsk@samsung.com>
  4 *               Krzysztof Opasiak <k.opasiak@samsung.com>
  5 *
  6 * Refactored from usbip_host_driver.c, which is:
  7 * Copyright (C) 2011 matt mooney <mfm@muteddisk.com>
  8 *               2005-2007 Takahiro Hirofuchi
  9 *
 10 * This program is free software: you can redistribute it and/or modify
 11 * it under the terms of the GNU General Public License as published by
 12 * the Free Software Foundation, either version 2 of the License, or
 13 * (at your option) any later version.
 14 *
 15 * This program is distributed in the hope that it will be useful,
 16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 18 * GNU General Public License for more details.
 19 *
 20 * You should have received a copy of the GNU General Public License
 21 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 22 */
 23
 24#include <sys/types.h>
 25#include <sys/stat.h>
 26#include <fcntl.h>
 27
 28#include <errno.h>
 29#include <unistd.h>
 30
 31#include <libudev.h>
 32
 33#include "usbip_common.h"
 34#include "usbip_host_common.h"
 35#include "list.h"
 36#include "sysfs_utils.h"
 37
 38struct udev *udev_context;
 39
 40static int32_t read_attr_usbip_status(struct usbip_usb_device *udev)
 41{
 42	char status_attr_path[SYSFS_PATH_MAX];
 43	int size;
 44	int fd;
 45	int length;
 46	char status;
 47	int value = 0;
 48
 49	size = snprintf(status_attr_path, sizeof(status_attr_path),
 50			"%s/usbip_status", udev->path);
 51	if (size < 0 || (unsigned int)size >= sizeof(status_attr_path)) {
 52		err("usbip_status path length %i >= %lu or < 0", size,
 53		    (long unsigned)sizeof(status_attr_path));
 54		return -1;
 55	}
 56
 57
 58	fd = open(status_attr_path, O_RDONLY);
 59	if (fd < 0) {
 60		err("error opening attribute %s", status_attr_path);
 61		return -1;
 62	}
 63
 64	length = read(fd, &status, 1);
 65	if (length < 0) {
 66		err("error reading attribute %s", status_attr_path);
 67		close(fd);
 68		return -1;
 69	}
 70
 71	value = atoi(&status);
 72
 73	return value;
 74}
 75
 76static
 77struct usbip_exported_device *usbip_exported_device_new(
 78		struct usbip_host_driver *hdriver, const char *sdevpath)
 79{
 80	struct usbip_exported_device *edev = NULL;
 81	struct usbip_exported_device *edev_old;
 82	size_t size;
 83	int i;
 84
 85	edev = calloc(1, sizeof(struct usbip_exported_device));
 86
 87	edev->sudev =
 88		udev_device_new_from_syspath(udev_context, sdevpath);
 89	if (!edev->sudev) {
 90		err("udev_device_new_from_syspath: %s", sdevpath);
 91		goto err;
 92	}
 93
 94	if (hdriver->ops.read_device(edev->sudev, &edev->udev) < 0)
 95		goto err;
 96
 97	edev->status = read_attr_usbip_status(&edev->udev);
 98	if (edev->status < 0)
 99		goto err;
100
101	/* reallocate buffer to include usb interface data */
102	size = sizeof(struct usbip_exported_device) +
103		edev->udev.bNumInterfaces * sizeof(struct usbip_usb_interface);
104
105	edev_old = edev;
106	edev = realloc(edev, size);
107	if (!edev) {
108		edev = edev_old;
109		dbg("realloc failed");
110		goto err;
111	}
112
113	for (i = 0; i < edev->udev.bNumInterfaces; i++) {
114		/* vudc does not support reading interfaces */
115		if (!hdriver->ops.read_interface)
116			break;
117		hdriver->ops.read_interface(&edev->udev, i, &edev->uinf[i]);
118	}
119
120	return edev;
121err:
122	if (edev->sudev)
123		udev_device_unref(edev->sudev);
124	if (edev)
125		free(edev);
126
127	return NULL;
128}
129
130static int refresh_exported_devices(struct usbip_host_driver *hdriver)
131{
132	struct usbip_exported_device *edev;
133	struct udev_enumerate *enumerate;
134	struct udev_list_entry *devices, *dev_list_entry;
135	struct udev_device *dev;
136	const char *path;
137
138	enumerate = udev_enumerate_new(udev_context);
139	udev_enumerate_add_match_subsystem(enumerate, hdriver->udev_subsystem);
140	udev_enumerate_scan_devices(enumerate);
141
142	devices = udev_enumerate_get_list_entry(enumerate);
143
144	udev_list_entry_foreach(dev_list_entry, devices) {
145		path = udev_list_entry_get_name(dev_list_entry);
146		dev = udev_device_new_from_syspath(udev_context,
147						   path);
148		if (dev == NULL)
149			continue;
150
151		/* Check whether device uses usbip driver. */
152		if (hdriver->ops.is_my_device(dev)) {
153			edev = usbip_exported_device_new(hdriver, path);
154			if (!edev) {
155				dbg("usbip_exported_device_new failed");
156				continue;
157			}
158
159			list_add(&edev->node, &hdriver->edev_list);
160			hdriver->ndevs++;
161		}
162	}
163
164	return 0;
165}
166
167static void usbip_exported_device_destroy(struct list_head *devs)
168{
169	struct list_head *i, *tmp;
170	struct usbip_exported_device *edev;
171
172	list_for_each_safe(i, tmp, devs) {
173		edev = list_entry(i, struct usbip_exported_device, node);
174		list_del(i);
175		free(edev);
176	}
177}
178
179int usbip_generic_driver_open(struct usbip_host_driver *hdriver)
180{
181	int rc;
182
183	udev_context = udev_new();
184	if (!udev_context) {
185		err("udev_new failed");
186		return -1;
187	}
188
189	rc = refresh_exported_devices(hdriver);
190	if (rc < 0)
191		goto err;
192	return 0;
193err:
194	udev_unref(udev_context);
195	return -1;
196}
197
198void usbip_generic_driver_close(struct usbip_host_driver *hdriver)
199{
200	if (!hdriver)
201		return;
202
203	usbip_exported_device_destroy(&hdriver->edev_list);
204
205	udev_unref(udev_context);
206}
207
208int usbip_generic_refresh_device_list(struct usbip_host_driver *hdriver)
209{
210	int rc;
211
212	usbip_exported_device_destroy(&hdriver->edev_list);
213
214	hdriver->ndevs = 0;
215	INIT_LIST_HEAD(&hdriver->edev_list);
216
217	rc = refresh_exported_devices(hdriver);
218	if (rc < 0)
219		return -1;
220
221	return 0;
222}
223
224int usbip_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	int size;
229	char sockfd_buff[30];
230	int ret;
231
232	if (edev->status != SDEV_ST_AVAILABLE) {
233		dbg("device not available: %s", edev->udev.busid);
234		switch (edev->status) {
235		case SDEV_ST_ERROR:
236			dbg("status SDEV_ST_ERROR");
237			ret = ST_DEV_ERR;
238			break;
239		case SDEV_ST_USED:
240			dbg("status SDEV_ST_USED");
241			ret = ST_DEV_BUSY;
242			break;
243		default:
244			dbg("status unknown: 0x%x", edev->status);
245			ret = -1;
246		}
247		return ret;
248	}
249
250	/* only the first interface is true */
251	size = snprintf(sockfd_attr_path, sizeof(sockfd_attr_path), "%s/%s",
252			edev->udev.path, attr_name);
253	if (size < 0 || (unsigned int)size >= sizeof(sockfd_attr_path)) {
254		err("exported device path length %i >= %lu or < 0", size,
255		    (long unsigned)sizeof(sockfd_attr_path));
256		return -1;
257	}
258
259	size = snprintf(sockfd_buff, sizeof(sockfd_buff), "%d\n", sockfd);
260	if (size < 0 || (unsigned int)size >= sizeof(sockfd_buff)) {
261		err("socket length %i >= %lu or < 0", size,
262		    (long unsigned)sizeof(sockfd_buff));
263		return -1;
264	}
265
266	ret = write_sysfs_attribute(sockfd_attr_path, sockfd_buff,
267				    strlen(sockfd_buff));
268	if (ret < 0) {
269		err("write_sysfs_attribute failed: sockfd %s to %s",
270		    sockfd_buff, sockfd_attr_path);
271		return ret;
272	}
273
274	info("connect: %s", edev->udev.busid);
275
276	return ret;
277}
278
279struct usbip_exported_device *usbip_generic_get_device(
280		struct usbip_host_driver *hdriver, int num)
281{
282	struct list_head *i;
283	struct usbip_exported_device *edev;
284	int cnt = 0;
285
286	list_for_each(i, &hdriver->edev_list) {
287		edev = list_entry(i, struct usbip_exported_device, node);
288		if (num == cnt)
289			return edev;
290		cnt++;
291	}
292
293	return NULL;
294}