1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2015-2016 Samsung Electronics
4 *               Igor Kotrasinski <i.kotrasinsk@samsung.com>
5 *               Krzysztof Opasiak <k.opasiak@samsung.com>
6 *
7 * Refactored from usbip_host_driver.c, which is:
8 * Copyright (C) 2011 matt mooney <mfm@muteddisk.com>
9 *               2005-2007 Takahiro Hirofuchi
10 */
11
12#include <sys/types.h>
13#include <sys/stat.h>
14#include <fcntl.h>
15
16#include <errno.h>
17#include <unistd.h>
18
19#include <libudev.h>
20
21#include "usbip_common.h"
22#include "usbip_host_common.h"
23#include "list.h"
24#include "sysfs_utils.h"
25
26extern struct udev *udev_context;
27
28static int32_t read_attr_usbip_status(struct usbip_usb_device *udev)
29{
30	char status_attr_path[SYSFS_PATH_MAX];
31	int size;
32	int fd;
33	int length;
34	char status[2] = { 0 };
35	int value = 0;
36
37	size = snprintf(status_attr_path, sizeof(status_attr_path),
38			"%s/usbip_status", udev->path);
39	if (size < 0 || (unsigned int)size >= sizeof(status_attr_path)) {
40		err("usbip_status path length %i >= %lu or < 0", size,
41		    (long unsigned)sizeof(status_attr_path));
42		return -1;
43	}
44
45
46	fd = open(status_attr_path, O_RDONLY);
47	if (fd < 0) {
48		err("error opening attribute %s", status_attr_path);
49		return -1;
50	}
51
52	length = read(fd, status, 1);
53	if (length < 0) {
54		err("error reading attribute %s", status_attr_path);
55		close(fd);
56		return -1;
57	}
58
59	value = atoi(status);
60	close(fd);
61	return value;
62}
63
64static
65struct usbip_exported_device *usbip_exported_device_new(
66		struct usbip_host_driver *hdriver, const char *sdevpath)
67{
68	struct usbip_exported_device *edev = NULL;
69	struct usbip_exported_device *edev_old;
70	size_t size;
71	int i;
72
73	edev = calloc(1, sizeof(struct usbip_exported_device));
74
75	edev->sudev =
76		udev_device_new_from_syspath(udev_context, sdevpath);
77	if (!edev->sudev) {
78		err("udev_device_new_from_syspath: %s", sdevpath);
79		goto err;
80	}
81
82	if (hdriver->ops.read_device(edev->sudev, &edev->udev) < 0)
83		goto err;
84
85	edev->status = read_attr_usbip_status(&edev->udev);
86	if (edev->status < 0)
87		goto err;
88
89	/* reallocate buffer to include usb interface data */
90	size = sizeof(struct usbip_exported_device) +
91		edev->udev.bNumInterfaces * sizeof(struct usbip_usb_interface);
92
93	edev_old = edev;
94	edev = realloc(edev, size);
95	if (!edev) {
96		edev = edev_old;
97		dbg("realloc failed");
98		goto err;
99	}
100
101	for (i = 0; i < edev->udev.bNumInterfaces; i++) {
102		/* vudc does not support reading interfaces */
103		if (!hdriver->ops.read_interface)
104			break;
105		hdriver->ops.read_interface(&edev->udev, i, &edev->uinf[i]);
106	}
107
108	return edev;
109err:
110	if (edev->sudev)
111		udev_device_unref(edev->sudev);
112	if (edev)
113		free(edev);
114
115	return NULL;
116}
117
118static int refresh_exported_devices(struct usbip_host_driver *hdriver)
119{
120	struct usbip_exported_device *edev;
121	struct udev_enumerate *enumerate;
122	struct udev_list_entry *devices, *dev_list_entry;
123	struct udev_device *dev;
124	const char *path;
125
126	enumerate = udev_enumerate_new(udev_context);
127	udev_enumerate_add_match_subsystem(enumerate, hdriver->udev_subsystem);
128	udev_enumerate_scan_devices(enumerate);
129
130	devices = udev_enumerate_get_list_entry(enumerate);
131
132	udev_list_entry_foreach(dev_list_entry, devices) {
133		path = udev_list_entry_get_name(dev_list_entry);
134		dev = udev_device_new_from_syspath(udev_context,
135						   path);
136		if (dev == NULL)
137			continue;
138
139		/* Check whether device uses usbip driver. */
140		if (hdriver->ops.is_my_device(dev)) {
141			edev = usbip_exported_device_new(hdriver, path);
142			if (!edev) {
143				dbg("usbip_exported_device_new failed");
144				continue;
145			}
146
147			list_add(&edev->node, &hdriver->edev_list);
148			hdriver->ndevs++;
149		}
150	}
151
152	return 0;
153}
154
155static void usbip_exported_device_destroy(struct list_head *devs)
156{
157	struct list_head *i, *tmp;
158	struct usbip_exported_device *edev;
159
160	list_for_each_safe(i, tmp, devs) {
161		edev = list_entry(i, struct usbip_exported_device, node);
162		list_del(i);
163		free(edev);
164	}
165}
166
167int usbip_generic_driver_open(struct usbip_host_driver *hdriver)
168{
169	int rc;
170
171	udev_context = udev_new();
172	if (!udev_context) {
173		err("udev_new failed");
174		return -1;
175	}
176
177	rc = refresh_exported_devices(hdriver);
178	if (rc < 0)
179		goto err;
180	return 0;
181err:
182	udev_unref(udev_context);
183	return -1;
184}
185
186void usbip_generic_driver_close(struct usbip_host_driver *hdriver)
187{
188	if (!hdriver)
189		return;
190
191	usbip_exported_device_destroy(&hdriver->edev_list);
192
193	udev_unref(udev_context);
194}
195
196int usbip_generic_refresh_device_list(struct usbip_host_driver *hdriver)
197{
198	int rc;
199
200	usbip_exported_device_destroy(&hdriver->edev_list);
201
202	hdriver->ndevs = 0;
203	INIT_LIST_HEAD(&hdriver->edev_list);
204
205	rc = refresh_exported_devices(hdriver);
206	if (rc < 0)
207		return -1;
208
209	return 0;
210}
211
212int usbip_export_device(struct usbip_exported_device *edev, int sockfd)
213{
214	char attr_name[] = "usbip_sockfd";
215	char sockfd_attr_path[SYSFS_PATH_MAX];
216	int size;
217	char sockfd_buff[30];
218	int ret;
219
220	if (edev->status != SDEV_ST_AVAILABLE) {
221		dbg("device not available: %s", edev->udev.busid);
222		switch (edev->status) {
223		case SDEV_ST_ERROR:
224			dbg("status SDEV_ST_ERROR");
225			ret = ST_DEV_ERR;
226			break;
227		case SDEV_ST_USED:
228			dbg("status SDEV_ST_USED");
229			ret = ST_DEV_BUSY;
230			break;
231		default:
232			dbg("status unknown: 0x%x", edev->status);
233			ret = -1;
234		}
235		return ret;
236	}
237
238	/* only the first interface is true */
239	size = snprintf(sockfd_attr_path, sizeof(sockfd_attr_path), "%s/%s",
240			edev->udev.path, attr_name);
241	if (size < 0 || (unsigned int)size >= sizeof(sockfd_attr_path)) {
242		err("exported device path length %i >= %lu or < 0", size,
243		    (long unsigned)sizeof(sockfd_attr_path));
244		return -1;
245	}
246
247	size = snprintf(sockfd_buff, sizeof(sockfd_buff), "%d\n", sockfd);
248	if (size < 0 || (unsigned int)size >= sizeof(sockfd_buff)) {
249		err("socket length %i >= %lu or < 0", size,
250		    (long unsigned)sizeof(sockfd_buff));
251		return -1;
252	}
253
254	ret = write_sysfs_attribute(sockfd_attr_path, sockfd_buff,
255				    strlen(sockfd_buff));
256	if (ret < 0) {
257		err("write_sysfs_attribute failed: sockfd %s to %s",
258		    sockfd_buff, sockfd_attr_path);
259		return ret;
260	}
261
262	info("connect: %s", edev->udev.busid);
263
264	return ret;
265}
266
267struct usbip_exported_device *usbip_generic_get_device(
268		struct usbip_host_driver *hdriver, int num)
269{
270	struct list_head *i;
271	struct usbip_exported_device *edev;
272	int cnt = 0;
273
274	list_for_each(i, &hdriver->edev_list) {
275		edev = list_entry(i, struct usbip_exported_device, node);
276		if (num == cnt)
277			return edev;
278		cnt++;
279	}
280
281	return NULL;
282}
283