cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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usbip_host_common.c (6409B)


      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}