+++ /dev/null
-/* -*- Mode: C; c-basic-offset:8 ; indent-tabs-mode:t -*- */
-/*
- * Linux usbfs backend for libusb
- * Copyright (C) 2007-2009 Daniel Drake <dsd@gentoo.org>
- * Copyright (c) 2001 Johannes Erdfelt <johannes@erdfelt.com>
- * Copyright (c) 2013 Nathan Hjelm <hjelmn@mac.com>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#include "config.h"
-#include "libusb.h"
-#include "libusbi.h"
-#include "linux_usbfs.h"
-
-#include <ctype.h>
-#include <dirent.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <poll.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/types.h>
-
-#ifdef HAVE_ASM_TYPES_H
-#include <asm/types.h>
-#endif
-
-#ifdef HAVE_SYS_SOCKET_H
-#include <sys/socket.h>
-#endif
-
-#include <arpa/inet.h>
-
-#ifdef HAVE_LINUX_NETLINK_H
-#include <linux/netlink.h>
-#endif
-
-#ifdef HAVE_LINUX_FILTER_H
-#include <linux/filter.h>
-#endif
-
-#define KERNEL 1
-
-static int linux_netlink_socket = -1;
-static int netlink_control_pipe[2] = { -1, -1 };
-static pthread_t libusb_linux_event_thread;
-
-static void *linux_netlink_event_thread_main(void *arg);
-
-struct sockaddr_nl snl = { .nl_family=AF_NETLINK, .nl_groups=KERNEL };
-
-static int set_fd_cloexec_nb (int fd)
-{
- int flags;
-
-#if defined(FD_CLOEXEC)
- flags = fcntl (linux_netlink_socket, F_GETFD);
- if (0 > flags) {
- return -1;
- }
-
- if (!(flags & FD_CLOEXEC)) {
- fcntl (linux_netlink_socket, F_SETFD, flags | FD_CLOEXEC);
- }
-#endif
-
- flags = fcntl (linux_netlink_socket, F_GETFL);
- if (0 > flags) {
- return -1;
- }
-
- if (!(flags & O_NONBLOCK)) {
- fcntl (linux_netlink_socket, F_SETFL, flags | O_NONBLOCK);
- }
-
- return 0;
-}
-
-int linux_netlink_start_event_monitor(void)
-{
- int socktype = SOCK_RAW;
- int ret;
-
- snl.nl_groups = KERNEL;
-
-#if defined(SOCK_CLOEXEC)
- socktype |= SOCK_CLOEXEC;
-#endif
-#if defined(SOCK_NONBLOCK)
- socktype |= SOCK_NONBLOCK;
-#endif
-
- linux_netlink_socket = socket(PF_NETLINK, socktype, NETLINK_KOBJECT_UEVENT);
- if (-1 == linux_netlink_socket && EINVAL == errno) {
- linux_netlink_socket = socket(PF_NETLINK, SOCK_RAW, NETLINK_KOBJECT_UEVENT);
- }
-
- if (-1 == linux_netlink_socket) {
- return LIBUSB_ERROR_OTHER;
- }
-
- ret = set_fd_cloexec_nb (linux_netlink_socket);
- if (0 != ret) {
- close (linux_netlink_socket);
- linux_netlink_socket = -1;
- return LIBUSB_ERROR_OTHER;
- }
-
- ret = bind(linux_netlink_socket, (struct sockaddr *) &snl, sizeof(snl));
- if (0 != ret) {
- close(linux_netlink_socket);
- return LIBUSB_ERROR_OTHER;
- }
-
- /* TODO -- add authentication */
- /* setsockopt(linux_netlink_socket, SOL_SOCKET, SO_PASSCRED, &one, sizeof(one)); */
-
- ret = usbi_pipe(netlink_control_pipe);
- if (ret) {
- usbi_err(NULL, "could not create netlink control pipe");
- close(linux_netlink_socket);
- return LIBUSB_ERROR_OTHER;
- }
-
- ret = pthread_create(&libusb_linux_event_thread, NULL, linux_netlink_event_thread_main, NULL);
- if (0 != ret) {
- close(netlink_control_pipe[0]);
- close(netlink_control_pipe[1]);
- close(linux_netlink_socket);
- return LIBUSB_ERROR_OTHER;
- }
-
- return LIBUSB_SUCCESS;
-}
-
-int linux_netlink_stop_event_monitor(void)
-{
- int r;
- char dummy = 1;
-
- if (-1 == linux_netlink_socket) {
- /* already closed. nothing to do */
- return LIBUSB_SUCCESS;
- }
-
- /* Write some dummy data to the control pipe and
- * wait for the thread to exit */
- r = usbi_write(netlink_control_pipe[1], &dummy, sizeof(dummy));
- if (r <= 0) {
- usbi_warn(NULL, "netlink control pipe signal failed");
- }
- pthread_join(libusb_linux_event_thread, NULL);
-
- close(linux_netlink_socket);
- linux_netlink_socket = -1;
-
- /* close and reset control pipe */
- close(netlink_control_pipe[0]);
- close(netlink_control_pipe[1]);
- netlink_control_pipe[0] = -1;
- netlink_control_pipe[1] = -1;
-
- return LIBUSB_SUCCESS;
-}
-
-static const char *netlink_message_parse (const char *buffer, size_t len, const char *key)
-{
- size_t keylen = strlen(key);
- size_t offset;
-
- for (offset = 0 ; offset < len && '\0' != buffer[offset] ; offset += strlen(buffer + offset) + 1) {
- if (0 == strncmp(buffer + offset, key, keylen) &&
- '=' == buffer[offset + keylen]) {
- return buffer + offset + keylen + 1;
- }
- }
-
- return NULL;
-}
-
-/* parse parts of netlink message common to both libudev and the kernel */
-static int linux_netlink_parse(char *buffer, size_t len, int *detached, const char **sys_name,
- uint8_t *busnum, uint8_t *devaddr) {
- const char *tmp;
- int i;
-
- errno = 0;
-
- *sys_name = NULL;
- *detached = 0;
- *busnum = 0;
- *devaddr = 0;
-
- tmp = netlink_message_parse((const char *) buffer, len, "ACTION");
- if (tmp == NULL)
- return -1;
- if (0 == strcmp(tmp, "remove")) {
- *detached = 1;
- } else if (0 != strcmp(tmp, "add")) {
- usbi_dbg("unknown device action %s", tmp);
- return -1;
- }
-
- /* check that this is a usb message */
- tmp = netlink_message_parse(buffer, len, "SUBSYSTEM");
- if (NULL == tmp || 0 != strcmp(tmp, "usb")) {
- /* not usb. ignore */
- return -1;
- }
-
- tmp = netlink_message_parse(buffer, len, "BUSNUM");
- if (NULL == tmp) {
- /* no bus number. try "DEVICE" */
- tmp = netlink_message_parse(buffer, len, "DEVICE");
- if (NULL == tmp) {
- /* not usb. ignore */
- return -1;
- }
-
- /* Parse a device path such as /dev/bus/usb/003/004 */
- char *pLastSlash = (char*)strrchr(tmp,'/');
- if(NULL == pLastSlash) {
- return -1;
- }
-
- *devaddr = strtoul(pLastSlash + 1, NULL, 10);
- if (errno) {
- errno = 0;
- return -1;
- }
-
- *busnum = strtoul(pLastSlash - 3, NULL, 10);
- if (errno) {
- errno = 0;
- return -1;
- }
-
- return 0;
- }
-
- *busnum = (uint8_t)(strtoul(tmp, NULL, 10) & 0xff);
- if (errno) {
- errno = 0;
- return -1;
- }
-
- tmp = netlink_message_parse(buffer, len, "DEVNUM");
- if (NULL == tmp) {
- return -1;
- }
-
- *devaddr = (uint8_t)(strtoul(tmp, NULL, 10) & 0xff);
- if (errno) {
- errno = 0;
- return -1;
- }
-
- tmp = netlink_message_parse(buffer, len, "DEVPATH");
- if (NULL == tmp) {
- return -1;
- }
-
- for (i = strlen(tmp) - 1 ; i ; --i) {
- if ('/' ==tmp[i]) {
- *sys_name = tmp + i + 1;
- break;
- }
- }
-
- /* found a usb device */
- return 0;
-}
-
-static int linux_netlink_read_message(void)
-{
- unsigned char buffer[1024];
- struct iovec iov = {.iov_base = buffer, .iov_len = sizeof(buffer)};
- struct msghdr meh = { .msg_iov=&iov, .msg_iovlen=1,
- .msg_name=&snl, .msg_namelen=sizeof(snl) };
- const char *sys_name = NULL;
- uint8_t busnum, devaddr;
- int detached, r;
- size_t len;
-
- /* read netlink message */
- memset(buffer, 0, sizeof(buffer));
- len = recvmsg(linux_netlink_socket, &meh, 0);
- if (len < 32) {
- if (errno != EAGAIN)
- usbi_dbg("error recieving message from netlink");
- return -1;
- }
-
- /* TODO -- authenticate this message is from the kernel or udevd */
-
- r = linux_netlink_parse(buffer, len, &detached, &sys_name,
- &busnum, &devaddr);
- if (r)
- return r;
-
- usbi_dbg("netlink hotplug found device busnum: %hhu, devaddr: %hhu, sys_name: %s, removed: %s",
- busnum, devaddr, sys_name, detached ? "yes" : "no");
-
- /* signal device is available (or not) to all contexts */
- if (detached)
- linux_device_disconnected(busnum, devaddr, sys_name);
- else
- linux_hotplug_enumerate(busnum, devaddr, sys_name);
-
- return 0;
-}
-
-static void *linux_netlink_event_thread_main(void *arg)
-{
- char dummy;
- int r;
- struct pollfd fds[] = {
- { .fd = netlink_control_pipe[0],
- .events = POLLIN },
- { .fd = linux_netlink_socket,
- .events = POLLIN },
- };
-
- /* silence compiler warning */
- (void) arg;
-
- while (poll(fds, 2, -1) >= 0) {
- if (fds[0].revents & POLLIN) {
- /* activity on control pipe, read the byte and exit */
- r = usbi_read(netlink_control_pipe[0], &dummy, sizeof(dummy));
- if (r <= 0) {
- usbi_warn(NULL, "netlink control pipe read failed");
- }
- break;
- }
- if (fds[1].revents & POLLIN) {
- usbi_mutex_static_lock(&linux_hotplug_lock);
- linux_netlink_read_message();
- usbi_mutex_static_unlock(&linux_hotplug_lock);
- }
- }
-
- return NULL;
-}
-
-void linux_netlink_hotplug_poll(void)
-{
- int r;
-
- usbi_mutex_static_lock(&linux_hotplug_lock);
- do {
- r = linux_netlink_read_message();
- } while (r == 0);
- usbi_mutex_static_unlock(&linux_hotplug_lock);
-}