#include <stddef.h>

#include <signal.h>

#include <unistd.h>

#include <errno.h>

#include <stdio.h>

#include <stdlib.h>

#include <stdbool.h>

#include <string.h>

#include <fcntl.h>

#include <getopt.h>

#include <sys/file.h>

#include <sys/time.h>

#include <sys/prctl.h>

#include <sys/socket.h>

#include <sys/signalfd.h>

#include <sys/epoll.h>

#include <sys/mount.h>

#include <sys/wait.h>

#include <sys/stat.h>

#include <sys/ioctl.h>

#include <sys/inotify.h>

#include "sd-daemon.h"

#include "rtnl-util.h"

#include "cgroup-util.h"

#include "dev-setup.h"

#include "fileio.h"

#include "selinux-util.h"

#include "udev.h"

#include "udev-util.h"

#include "formats-util.h"

#include "hashmap.h"

static struct udev_rules *rules;

static struct udev_ctrl *udev_ctrl;

static struct udev_ctrl_connection *udev_ctrl_conn;

static struct udev_monitor *monitor;

static int worker_watch[2] = { -1, -1 };

static int fd_signal = -1;

static int fd_ep = -1;

static int fd_inotify = -1;

static bool stop_exec_queue;

static bool reload;

static bool arg_debug = false;

static int arg_daemonize = false;

static int arg_resolve_names = 1;

static unsigned arg_children_max;

static int arg_exec_delay;

static usec_t arg_event_timeout_usec = 180 * USEC_PER_SEC;

static usec_t arg_event_timeout_warn_usec = 180 * USEC_PER_SEC / 3;

static sigset_t sigmask_orig;

static UDEV_LIST(event_list);

Hashmap *workers;

static char *udev_cgroup;

static struct udev_list properties_list;

static bool udev_exit;

enum event_state {

EVENT_UNDEF,

EVENT_QUEUED,

EVENT_RUNNING,

};

struct event {

struct udev_list_node node;

struct udev *udev;

struct udev_device *dev;

struct udev_device *dev_kernel;

struct worker *worker;

enum event_state state;

unsigned long long int delaying_seqnum;

unsigned long long int seqnum;

const char *devpath;

size_t devpath_len;

const char *devpath_old;

dev_t devnum;

int ifindex;

bool is_block;

usec_t start_usec;

bool warned;

};

static inline struct event *node_to_event(struct udev_list_node *node) {

return container_of(node, struct event, node);

}

static void event_queue_cleanup(struct udev *udev, enum event_state type);

enum worker_state {

WORKER_UNDEF,

WORKER_RUNNING,

WORKER_IDLE,

WORKER_KILLED,

};

struct worker {

struct udev_list_node node;

struct udev *udev;

int refcount;

pid_t pid;

struct udev_monitor *monitor;

enum worker_state state;

struct event *event;

};

struct worker_message {

};

static void event_free(struct event *event) {

if (!event)

return;

udev_list_node_remove(&event->node);

udev_device_unref(event->dev);

udev_device_unref(event->dev_kernel);

if (event->worker)

event->worker->event = NULL;

free(event);

}

static void worker_free(struct worker *worker) {

if (!worker)

return;

hashmap_remove(workers, UINT_TO_PTR(worker->pid));

udev_monitor_unref(worker->monitor);

udev_unref(worker->udev);

event_free(worker->event);

free(worker);

}

static void workers_free(void) {

struct worker *worker;

Iterator i;

HASHMAP_FOREACH(worker, workers, i)

worker_free(worker);

hashmap_free(workers);

workers = NULL;

}

static int worker_new(struct worker **ret, struct udev *udev, struct udev_monitor *worker_monitor, pid_t pid) {

_cleanup_free_ struct worker *worker = NULL;

int r;

assert(ret);

assert(udev);

assert(worker_monitor);

assert(pid > 1);

worker = new0(struct worker, 1);

if (!worker)

return -ENOMEM;

worker->refcount = 1;

worker->udev = udev_ref(udev);

/* close monitor, but keep address around */

udev_monitor_disconnect(worker_monitor);

worker->monitor = udev_monitor_ref(worker_monitor);

worker->pid = pid;

r = hashmap_ensure_allocated(&workers, NULL);

if (r < 0)

return r;

r = hashmap_put(workers, UINT_TO_PTR(pid), worker);

if (r < 0)

return r;

*ret = worker;

worker = NULL;

return 0;

}

static void worker_attach_event(struct worker *worker, struct event *event) {

assert(worker);

assert(event);

assert(!event->worker);

assert(!worker->event);

worker->state = WORKER_RUNNING;

worker->event = event;

event->state = EVENT_RUNNING;

event->start_usec = now(CLOCK_MONOTONIC);

event->warned = false;

event->worker = worker;

}

static void worker_spawn(struct event *event) {

struct udev *udev = event->udev;

_cleanup_udev_monitor_unref_ struct udev_monitor *worker_monitor = NULL;

pid_t pid;

/* listen for new events */

worker_monitor = udev_monitor_new_from_netlink(udev, NULL);

if (worker_monitor == NULL)

return;

/* allow the main daemon netlink address to send devices to the worker */

udev_monitor_allow_unicast_sender(worker_monitor, monitor);

udev_monitor_enable_receiving(worker_monitor);

pid = fork();

switch (pid) {

case 0: {

struct udev_device *dev = NULL;

int fd_monitor;

_cleanup_rtnl_unref_ sd_rtnl *rtnl = NULL;

struct epoll_event ep_signal, ep_monitor;

sigset_t mask;

int r = 0;

/* take initial device from queue */

dev = event->dev;

event->dev = NULL;

workers_free();

event_queue_cleanup(udev, EVENT_UNDEF);

udev_monitor_unref(monitor);

udev_ctrl_unref(udev_ctrl);

close(fd_signal);

close(fd_ep);

close(worker_watch[READ_END]);

sigfillset(&mask);

fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);

if (fd_signal < 0) {

r = log_error_errno(errno, "error creating signalfd %m");

goto out;

}

fd_ep = epoll_create1(EPOLL_CLOEXEC);

if (fd_ep < 0) {

r = log_error_errno(errno, "error creating epoll fd: %m");

goto out;

}

memzero(&ep_signal, sizeof(struct epoll_event));

ep_signal.events = EPOLLIN;

ep_signal.data.fd = fd_signal;

fd_monitor = udev_monitor_get_fd(worker_monitor);

memzero(&ep_monitor, sizeof(struct epoll_event));

ep_monitor.events = EPOLLIN;

ep_monitor.data.fd = fd_monitor;

if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||

epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_monitor, &ep_monitor) < 0) {

r = log_error_errno(errno, "fail to add fds to epoll: %m");

goto out;

}

/* request TERM signal if parent exits */

prctl(PR_SET_PDEATHSIG, SIGTERM);

/* reset OOM score, we only protect the main daemon */

write_string_file("/proc/self/oom_score_adj", "0");

for (;;) {

struct udev_event *udev_event;

struct worker_message msg;

int fd_lock = -1;

log_debug("seq %llu running", udev_device_get_seqnum(dev));

udev_event = udev_event_new(dev);

if (udev_event == NULL) {

r = -ENOMEM;

goto out;

}

/* needed for SIGCHLD/SIGTERM in spawn() */

udev_event->fd_signal = fd_signal;

if (arg_exec_delay > 0)

udev_event->exec_delay = arg_exec_delay;

/*

if (!streq_ptr(udev_device_get_action(dev), "remove") &&

streq_ptr("block", udev_device_get_subsystem(dev)) &&

!startswith(udev_device_get_sysname(dev), "dm-") &&

!startswith(udev_device_get_sysname(dev), "md")) {

struct udev_device *d = dev;

if (streq_ptr("partition", udev_device_get_devtype(d)))

d = udev_device_get_parent(d);

if (d) {

fd_lock = open(udev_device_get_devnode(d), O_RDONLY|O_CLOEXEC|O_NOFOLLOW|O_NONBLOCK);

if (fd_lock >= 0 && flock(fd_lock, LOCK_SH|LOCK_NB) < 0) {

log_debug_errno(errno, "Unable to flock(%s), skipping event handling: %m", udev_device_get_devnode(d));

fd_lock = safe_close(fd_lock);

r = -EAGAIN;

goto skip;

}

}

}

/* needed for renaming netifs */

udev_event->rtnl = rtnl;

/* apply rules, create node, symlinks */

udev_event_execute_rules(udev_event,

arg_event_timeout_usec, arg_event_timeout_warn_usec,

&properties_list,

rules,

&sigmask_orig);

udev_event_execute_run(udev_event,

arg_event_timeout_usec, arg_event_timeout_warn_usec,

&sigmask_orig);

if (udev_event->rtnl)

/* in case rtnl was initialized */

rtnl = sd_rtnl_ref(udev_event->rtnl);

/* apply/restore inotify watch */

if (udev_event->inotify_watch) {

udev_watch_begin(udev, dev);

udev_device_update_db(dev);

}

safe_close(fd_lock);

/* send processed event back to libudev listeners */

udev_monitor_send_device(worker_monitor, NULL, dev);

skip:

log_debug("seq %llu processed", udev_device_get_seqnum(dev));

/* send udevd the result of the event execution */

memzero(&msg, sizeof(struct worker_message));

r = send(worker_watch[WRITE_END], &msg, sizeof(struct worker_message), 0);

if (r < 0)

log_error_errno(errno, "failed to send result of seq %llu to main daemon: %m",

udev_device_get_seqnum(dev));

udev_device_unref(dev);

dev = NULL;

if (udev_event->sigterm) {

udev_event_unref(udev_event);

goto out;

}

udev_event_unref(udev_event);

/* wait for more device messages from main udevd, or term signal */

while (dev == NULL) {

struct epoll_event ev[4];

int fdcount;

int i;

fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), -1);

if (fdcount < 0) {

if (errno == EINTR)

continue;

r = log_error_errno(errno, "failed to poll: %m");

goto out;

}

for (i = 0; i < fdcount; i++) {

if (ev[i].data.fd == fd_monitor && ev[i].events & EPOLLIN) {

dev = udev_monitor_receive_device(worker_monitor);

break;

} else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN) {

struct signalfd_siginfo fdsi;

ssize_t size;

size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));

if (size != sizeof(struct signalfd_siginfo))

continue;

switch (fdsi.ssi_signo) {

case SIGTERM:

goto out;

}

}

}

}

}

out:

udev_device_unref(dev);

safe_close(fd_signal);

safe_close(fd_ep);

close(fd_inotify);

close(worker_watch[WRITE_END]);

udev_rules_unref(rules);

udev_builtin_exit(udev);

udev_unref(udev);

log_close();

_exit(r < 0 ? EXIT_FAILURE : EXIT_SUCCESS);

}

case -1:

event->state = EVENT_QUEUED;

log_error_errno(errno, "fork of child failed: %m");

break;

default:

{

struct worker *worker;

int r;

r = worker_new(&worker, udev, worker_monitor, pid);

if (r < 0)

return;

worker_attach_event(worker, event);

log_debug("seq %llu forked new worker ["PID_FMT"]", udev_device_get_seqnum(event->dev), pid);

break;

}

}

}

static void event_run(struct event *event) {

struct worker *worker;

Iterator i;

HASHMAP_FOREACH(worker, workers, i) {

ssize_t count;

if (worker->state != WORKER_IDLE)

continue;

count = udev_monitor_send_device(monitor, worker->monitor, event->dev);

if (count < 0) {

log_error_errno(errno, "worker ["PID_FMT"] did not accept message %zi (%m), kill it",

worker->pid, count);

kill(worker->pid, SIGKILL);

worker->state = WORKER_KILLED;

continue;

}

worker_attach_event(worker, event);

return;

}

if (hashmap_size(workers) >= arg_children_max) {

if (arg_children_max > 1)

log_debug("maximum number (%i) of children reached", hashmap_size(workers));

return;

}

/* start new worker and pass initial device */

worker_spawn(event);

}

static int event_queue_insert(struct udev_device *dev) {

struct event *event;

event = new0(struct event, 1);

if (event == NULL)

return -1;

event->udev = udev_device_get_udev(dev);

event->dev = dev;

event->dev_kernel = udev_device_shallow_clone(dev);

udev_device_copy_properties(event->dev_kernel, dev);

event->seqnum = udev_device_get_seqnum(dev);

event->devpath = udev_device_get_devpath(dev);

event->devpath_len = strlen(event->devpath);

event->devpath_old = udev_device_get_devpath_old(dev);

event->devnum = udev_device_get_devnum(dev);

event->is_block = streq("block", udev_device_get_subsystem(dev));

event->ifindex = udev_device_get_ifindex(dev);

log_debug("seq %llu queued, '%s' '%s'", udev_device_get_seqnum(dev),

udev_device_get_action(dev), udev_device_get_subsystem(dev));

event->state = EVENT_QUEUED;

udev_list_node_append(&event->node, &event_list);

return 0;

}

static void worker_kill(void) {

struct worker *worker;

Iterator i;

HASHMAP_FOREACH(worker, workers, i) {

if (worker->state == WORKER_KILLED)

continue;

worker->state = WORKER_KILLED;

kill(worker->pid, SIGTERM);

}

}

static bool is_devpath_busy(struct event *event) {

struct udev_list_node *loop;

size_t common;

/* check if queue contains events we depend on */

udev_list_node_foreach(loop, &event_list) {

struct event *loop_event = node_to_event(loop);

/* we already found a later event, earlier can not block us, no need to check again */

if (loop_event->seqnum < event->delaying_seqnum)

continue;

/* event we checked earlier still exists, no need to check again */

if (loop_event->seqnum == event->delaying_seqnum)

return true;

/* found ourself, no later event can block us */

if (loop_event->seqnum >= event->seqnum)

break;

/* check major/minor */

if (major(event->devnum) != 0 && event->devnum == loop_event->devnum && event->is_block == loop_event->is_block)

return true;

/* check network device ifindex */

if (event->ifindex != 0 && event->ifindex == loop_event->ifindex)

return true;

/* check our old name */

if (event->devpath_old != NULL && streq(loop_event->devpath, event->devpath_old)) {

event->delaying_seqnum = loop_event->seqnum;

return true;

}

/* compare devpath */

common = MIN(loop_event->devpath_len, event->devpath_len);

/* one devpath is contained in the other? */

if (memcmp(loop_event->devpath, event->devpath, common) != 0)

continue;

/* identical device event found */

if (loop_event->devpath_len == event->devpath_len) {

/* devices names might have changed/swapped in the meantime */

if (major(event->devnum) != 0 && (event->devnum != loop_event->devnum || event->is_block != loop_event->is_block))

continue;

if (event->ifindex != 0 && event->ifindex != loop_event->ifindex)

continue;

event->delaying_seqnum = loop_event->seqnum;

return true;

}

/* parent device event found */

if (event->devpath[common] == '/') {

event->delaying_seqnum = loop_event->seqnum;

return true;

}

/* child device event found */

if (loop_event->devpath[common] == '/') {

event->delaying_seqnum = loop_event->seqnum;

return true;

}

/* no matching device */

continue;

}

return false;

}

static void event_queue_start(struct udev *udev) {

struct udev_list_node *loop;

udev_list_node_foreach(loop, &event_list) {

struct event *event = node_to_event(loop);

if (event->state != EVENT_QUEUED)

continue;

/* do not start event if parent or child event is still running */

if (is_devpath_busy(event))

continue;

event_run(event);

}

}

static void event_queue_cleanup(struct udev *udev, enum event_state match_type) {

struct udev_list_node *loop, *tmp;

udev_list_node_foreach_safe(loop, tmp, &event_list) {

struct event *event = node_to_event(loop);

if (match_type != EVENT_UNDEF && match_type != event->state)

continue;

event_free(event);

}

}

static int on_worker(sd_event_source *s, int fd, uint32_t revents, void *userdata) {

for (;;) {

struct worker_message msg;

struct iovec iovec = {

.iov_base = &msg,

.iov_len = sizeof(msg),

};

union {

struct cmsghdr cmsghdr;

uint8_t buf[CMSG_SPACE(sizeof(struct ucred))];

} control = {};

struct msghdr msghdr = {

.msg_iov = &iovec,

.msg_iovlen = 1,

.msg_control = &control,

.msg_controllen = sizeof(control),

};

struct cmsghdr *cmsg;

ssize_t size;

struct ucred *ucred = NULL;

struct worker *worker;

size = recvmsg(fd, &msghdr, MSG_DONTWAIT);

if (size < 0) {

if (errno == EAGAIN || errno == EINTR)

return 1;

return log_error_errno(errno, "failed to receive message: %m");

} else if (size != sizeof(struct worker_message)) {

log_warning_errno(EIO, "ignoring worker message with invalid size %zi bytes", size);

continue;

}

for (cmsg = CMSG_FIRSTHDR(&msghdr); cmsg; cmsg = CMSG_NXTHDR(&msghdr, cmsg)) {

if (cmsg->cmsg_level == SOL_SOCKET &&

cmsg->cmsg_type == SCM_CREDENTIALS &&

cmsg->cmsg_len == CMSG_LEN(sizeof(struct ucred)))

ucred = (struct ucred*) CMSG_DATA(cmsg);

}

if (!ucred || ucred->pid <= 0) {

log_warning_errno(EIO, "ignoring worker message without valid PID");

continue;

}

/* lookup worker who sent the signal */

worker = hashmap_get(workers, UINT_TO_PTR(ucred->pid));

if (!worker) {

log_debug("worker ["PID_FMT"] returned, but is no longer tracked", ucred->pid);

continue;

}

if (worker->state != WORKER_KILLED)

worker->state = WORKER_IDLE;

/* worker returned */

event_free(worker->event);

}

return 1;

}

static int on_uevent(sd_event_source *s, int fd, uint32_t revents, void *userdata) {

struct udev_monitor *m = userdata;

struct udev_device *dev;

int r;

assert(m);

dev = udev_monitor_receive_device(m);

if (dev) {

udev_device_ensure_usec_initialized(dev, NULL);

r = event_queue_insert(dev);

if (r < 0)

udev_device_unref(dev);

}

return 1;

}

static void event_queue_update(void) {

int r;

if (!udev_list_node_is_empty(&event_list)) {

r = touch("/run/udev/queue");

if (r < 0)

log_warning_errno(r, "could not touch /run/udev/queue: %m");

} else {

r = unlink("/run/udev/queue");

if (r < 0 && errno != ENOENT)

log_warning("could not unlink /run/udev/queue: %m");

}

}

static int on_ctrl_msg(sd_event_source *s, int fd, uint32_t revents, void *userdata) {

struct udev_ctrl *uctrl = userdata;

_cleanup_udev_ctrl_connection_unref_ struct udev_ctrl_connection *ctrl_conn = NULL;

_cleanup_udev_ctrl_msg_unref_ struct udev_ctrl_msg *ctrl_msg = NULL;

const char *str;

int i;

assert(uctrl);

ctrl_conn = udev_ctrl_get_connection(uctrl);

if (!ctrl_conn)

return 1;

ctrl_msg = udev_ctrl_receive_msg(ctrl_conn);

if (!ctrl_msg)

return 1;

i = udev_ctrl_get_set_log_level(ctrl_msg);

if (i >= 0) {

log_debug("udevd message (SET_LOG_LEVEL) received, log_priority=%i", i);

log_set_max_level(i);

worker_kill();

}

if (udev_ctrl_get_stop_exec_queue(ctrl_msg) > 0) {

log_debug("udevd message (STOP_EXEC_QUEUE) received");

stop_exec_queue = true;

}

if (udev_ctrl_get_start_exec_queue(ctrl_msg) > 0) {

log_debug("udevd message (START_EXEC_QUEUE) received");

stop_exec_queue = false;

}

if (udev_ctrl_get_reload(ctrl_msg) > 0) {

log_debug("udevd message (RELOAD) received");

reload = true;

}

str = udev_ctrl_get_set_env(ctrl_msg);

if (str != NULL) {

char *key;

key = strdup(str);

if (key != NULL) {

char *val;

val = strchr(key, '=');

if (val != NULL) {

val[0] = '\0';

val = &val[1];

if (val[0] == '\0') {

log_debug("udevd message (ENV) received, unset '%s'", key);

udev_list_entry_add(&properties_list, key, NULL);

} else {

log_debug("udevd message (ENV) received, set '%s=%s'", key, val);

udev_list_entry_add(&properties_list, key, val);

}

} else {

log_error("wrong key format '%s'", key);

}

free(key);

}

worker_kill();

}

i = udev_ctrl_get_set_children_max(ctrl_msg);

if (i >= 0) {

log_debug("udevd message (SET_MAX_CHILDREN) received, children_max=%i", i);

arg_children_max = i;

}

if (udev_ctrl_get_ping(ctrl_msg) > 0) {

log_debug("udevd message (SYNC) received");

/* tell settle that we are busy or idle, this needs to be before the

event_queue_update();

}

if (udev_ctrl_get_exit(ctrl_msg) > 0) {

log_debug("udevd message (EXIT) received");

udev_exit = true;

/* keep reference to block the client until we exit */

udev_ctrl_conn = udev_ctrl_connection_ref(ctrl_conn);

}

return 1;

}

static int synthesize_change(struct udev_device *dev) {

char filename[UTIL_PATH_SIZE];

int r;

if (streq_ptr("block", udev_device_get_subsystem(dev)) &&

streq_ptr("disk", udev_device_get_devtype(dev)) &&

!startswith(udev_device_get_sysname(dev), "dm-")) {

bool part_table_read = false;

bool has_partitions = false;

int fd;

struct udev *udev = udev_device_get_udev(dev);

_cleanup_udev_enumerate_unref_ struct udev_enumerate *e = NULL;

struct udev_list_entry *item;

/*

fd = open(udev_device_get_devnode(dev), O_RDONLY|O_CLOEXEC|O_NOFOLLOW|O_NONBLOCK);

if (fd >= 0) {

r = flock(fd, LOCK_EX|LOCK_NB);

if (r >= 0)

r = ioctl(fd, BLKRRPART, 0);

close(fd);

if (r >= 0)

part_table_read = true;

}

/* search for partitions */

e = udev_enumerate_new(udev);

if (!e)

return -ENOMEM;

r = udev_enumerate_add_match_parent(e, dev);

if (r < 0)

return r;

r = udev_enumerate_add_match_subsystem(e, "block");

if (r < 0)

return r;

r = udev_enumerate_scan_devices(e);

if (r < 0)

return r;

udev_list_entry_foreach(item, udev_enumerate_get_list_entry(e)) {

_cleanup_udev_device_unref_ struct udev_device *d = NULL;

d = udev_device_new_from_syspath(udev, udev_list_entry_get_name(item));

if (!d)

continue;

if (!streq_ptr("partition", udev_device_get_devtype(d)))

continue;

has_partitions = true;

break;

}

/*

if (part_table_read && has_partitions)

return 0;

/*

log_debug("device %s closed, synthesising 'change'", udev_device_get_devnode(dev));

strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL);

write_string_file(filename, "change");

udev_list_entry_foreach(item, udev_enumerate_get_list_entry(e)) {

_cleanup_udev_device_unref_ struct udev_device *d = NULL;

d = udev_device_new_from_syspath(udev, udev_list_entry_get_name(item));

if (!d)

continue;

if (!streq_ptr("partition", udev_device_get_devtype(d)))

continue;

log_debug("device %s closed, synthesising partition '%s' 'change'",

udev_device_get_devnode(dev), udev_device_get_devnode(d));

strscpyl(filename, sizeof(filename), udev_device_get_syspath(d), "/uevent", NULL);

write_string_file(filename, "change");

}

return 0;

}

log_debug("device %s closed, synthesising 'change'", udev_device_get_devnode(dev));

strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL);

write_string_file(filename, "change");

return 0;

}

static int on_inotify(sd_event_source *s, int fd, uint32_t revents, void *userdata) {

struct udev *udev = userdata;

union inotify_event_buffer buffer;

struct inotify_event *e;

ssize_t l;

assert(udev);

l = read(fd, &buffer, sizeof(buffer));

if (l < 0) {

if (errno == EAGAIN || errno == EINTR)

return 1;

return log_error_errno(errno, "Failed to read inotify fd: %m");

}

FOREACH_INOTIFY_EVENT(e, buffer, l) {

_cleanup_udev_device_unref_ struct udev_device *dev = NULL;

dev = udev_watch_lookup(udev, e->wd);

if (!dev)

continue;

log_debug("inotify event: %x for %s", e->mask, udev_device_get_devnode(dev));

if (e->mask & IN_CLOSE_WRITE) {

synthesize_change(dev);

/* settle might be waiting on us to determine the queue

on_uevent(NULL, -1, 0, monitor);

} else if (e->mask & IN_IGNORED)

udev_watch_end(udev, dev);

}

return 1;

}

static int on_request_exit(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {

udev_exit = true;

return 1;

}

static int on_request_reload(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {

reload = true;

return 1;

}

static int on_sigchld(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {

for (;;) {

pid_t pid;

int status;

struct worker *worker;

pid = waitpid(-1, &status, WNOHANG);

if (pid <= 0)

return 1;

worker = hashmap_get(workers, UINT_TO_PTR(pid));

if (!worker) {

log_warning("worker ["PID_FMT"] is unknown, ignoring", pid);

return 1;

}

if (WIFEXITED(status)) {

if (WEXITSTATUS(status) == 0)

log_debug("worker ["PID_FMT"] exited", pid);

else

log_warning("worker ["PID_FMT"] exited with return code %i", pid, WEXITSTATUS(status));

} else if (WIFSIGNALED(status)) {

log_warning("worker ["PID_FMT"] terminated by signal %i (%s)", pid, WTERMSIG(status), strsignal(WTERMSIG(status)));

} else if (WIFSTOPPED(status)) {

log_info("worker ["PID_FMT"] stopped", pid);

return 1;

} else if (WIFCONTINUED(status)) {

log_info("worker ["PID_FMT"] continued", pid);

return 1;

} else

log_warning("worker ["PID_FMT"] exit with status 0x%04x", pid, status);

if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {

if (worker->event) {

log_error("worker ["PID_FMT"] failed while handling '%s'", pid, worker->event->devpath);

/* delete state from disk */

udev_device_delete_db(worker->event->dev);

udev_device_tag_index(worker->event->dev, NULL, false);

/* forward kernel event without amending it */

udev_monitor_send_device(monitor, NULL, worker->event->dev_kernel);

}

}

worker_free(worker);

}

return 1;

}

static int systemd_fds(struct udev *udev, int *rctrl, int *rnetlink) {

int ctrl = -1, netlink = -1;

int fd, n;

n = sd_listen_fds(true);

if (n <= 0)

return -1;

for (fd = SD_LISTEN_FDS_START; fd < n + SD_LISTEN_FDS_START; fd++) {

if (sd_is_socket(fd, AF_LOCAL, SOCK_SEQPACKET, -1)) {

if (ctrl >= 0)

return -1;

ctrl = fd;

continue;

}

if (sd_is_socket(fd, AF_NETLINK, SOCK_RAW, -1)) {

if (netlink >= 0)

return -1;

netlink = fd;

continue;

}

return -1;

}

if (ctrl < 0 || netlink < 0)

return -1;

log_debug("ctrl=%i netlink=%i", ctrl, netlink);

*rctrl = ctrl;

*rnetlink = netlink;

return 0;

}

static int parse_proc_cmdline_item(const char *key, const char *value) {

int r;

assert(key);

if (!value)

return 0;

if (startswith(key, "rd."))

key += strlen("rd.");

if (startswith(key, "udev."))

key += strlen("udev.");

else

return 0;

if (streq(key, "log-priority")) {

int prio;

prio = util_log_priority(value);

log_set_max_level(prio);

} else if (streq(key, "children-max")) {

r = safe_atou(value, &arg_children_max);

if (r < 0)

log_warning("invalid udev.children-max ignored: %s", value);

} else if (streq(key, "exec-delay")) {

r = safe_atoi(value, &arg_exec_delay);

if (r < 0)

log_warning("invalid udev.exec-delay ignored: %s", value);

} else if (streq(key, "event-timeout")) {

r = safe_atou64(value, &arg_event_timeout_usec);

if (r < 0)

log_warning("invalid udev.event-timeout ignored: %s", value);

else {

arg_event_timeout_usec *= USEC_PER_SEC;

arg_event_timeout_warn_usec = (arg_event_timeout_usec / 3) ? : 1;

}

}

return 0;

}

static void help(void) {

printf("%s [OPTIONS...]\n\n"

"Manages devices.\n\n"

" -h --help Print this message\n"

" --version Print version of the program\n"

" --daemon Detach and run in the background\n"

" --debug Enable debug output\n"

" --children-max=INT Set maximum number of workers\n"

" --exec-delay=SECONDS Seconds to wait before executing RUN=\n"

" --event-timeout=SECONDS Seconds to wait before terminating an event\n"

" --resolve-names=early|late|never\n"

" When to resolve users and groups\n"

, program_invocation_short_name);

}

static int parse_argv(int argc, char *argv[]) {

static const struct option options[] = {

{ "daemon", no_argument, NULL, 'd' },

{ "debug", no_argument, NULL, 'D' },

{ "children-max", required_argument, NULL, 'c' },

{ "exec-delay", required_argument, NULL, 'e' },

{ "event-timeout", required_argument, NULL, 't' },

{ "resolve-names", required_argument, NULL, 'N' },

{ "help", no_argument, NULL, 'h' },

{ "version", no_argument, NULL, 'V' },

{}

};

int c;

assert(argc >= 0);

assert(argv);

while ((c = getopt_long(argc, argv, "c:de:DtN:hV", options, NULL)) >= 0) {

int r;

switch (c) {

case 'd':

arg_daemonize = true;

break;

case 'c':

r = safe_atou(optarg, &arg_children_max);

if (r < 0)

log_warning("Invalid --children-max ignored: %s", optarg);

break;

case 'e':

r = safe_atoi(optarg, &arg_exec_delay);

if (r < 0)

log_warning("Invalid --exec-delay ignored: %s", optarg);

break;

case 't':

r = safe_atou64(optarg, &arg_event_timeout_usec);

if (r < 0)

log_warning("Invalid --event-timeout ignored: %s", optarg);

else {

arg_event_timeout_usec *= USEC_PER_SEC;

arg_event_timeout_warn_usec = (arg_event_timeout_usec / 3) ? : 1;

}

break;

case 'D':

arg_debug = true;

break;

case 'N':

if (streq(optarg, "early")) {

arg_resolve_names = 1;

} else if (streq(optarg, "late")) {

arg_resolve_names = 0;

} else if (streq(optarg, "never")) {

arg_resolve_names = -1;

} else {

log_error("resolve-names must be early, late or never");

return 0;

}

break;

case 'h':

help();

return 0;

case 'V':

printf("%s\n", VERSION);

return 0;

case '?':

return -EINVAL;

default:

assert_not_reached("Unhandled option");

}

}

return 1;

}

int main(int argc, char *argv[]) {

struct udev *udev;

sigset_t mask;

int fd_ctrl = -1;

int fd_netlink = -1;

int fd_worker = -1;

struct epoll_event ep_ctrl = { .events = EPOLLIN };

struct epoll_event ep_inotify = { .events = EPOLLIN };

struct epoll_event ep_signal = { .events = EPOLLIN };

struct epoll_event ep_netlink = { .events = EPOLLIN };

struct epoll_event ep_worker = { .events = EPOLLIN };

int r = 0, one = 1;

udev = udev_new();

if (!udev) {

r = log_error_errno(errno, "could not allocate udev context: %m");

goto exit;

}

log_set_target(LOG_TARGET_AUTO);

log_parse_environment();

log_open();

r = parse_argv(argc, argv);

if (r <= 0)

goto exit;

r = parse_proc_cmdline(parse_proc_cmdline_item);

if (r < 0)

log_warning_errno(r, "failed to parse kernel command line, ignoring: %m");

if (arg_debug)

log_set_max_level(LOG_DEBUG);

if (getuid() != 0) {

r = log_error_errno(EPERM, "root privileges required");

goto exit;

}

r = mac_selinux_init("/dev");

if (r < 0) {

log_error_errno(r, "could not initialize labelling: %m");

goto exit;

}

/* set umask before creating any file/directory */

r = chdir("/");

if (r < 0) {

r = log_error_errno(errno, "could not change dir to /: %m");

goto exit;

}

umask(022);

udev_list_init(udev, &properties_list, true);

r = mkdir("/run/udev", 0755);

if (r < 0 && errno != EEXIST) {

r = log_error_errno(errno, "could not create /run/udev: %m");

goto exit;

}

dev_setup(NULL);

/* before opening new files, make sure std{in,out,err} fds are in a sane state */

if (arg_daemonize) {

int fd;

fd = open("/dev/null", O_RDWR);

if (fd >= 0) {

if (write(STDOUT_FILENO, 0, 0) < 0)

dup2(fd, STDOUT_FILENO);

if (write(STDERR_FILENO, 0, 0) < 0)

dup2(fd, STDERR_FILENO);

if (fd > STDERR_FILENO)

close(fd);

} else {

log_error("cannot open /dev/null");

}

}

if (systemd_fds(udev, &fd_ctrl, &fd_netlink) >= 0) {

/* get control and netlink socket from systemd */

udev_ctrl = udev_ctrl_new_from_fd(udev, fd_ctrl);

if (!udev_ctrl) {

r = log_error_errno(EINVAL, "error taking over udev control socket");

goto exit;

}

monitor = udev_monitor_new_from_netlink_fd(udev, "kernel", fd_netlink);

if (!monitor) {

r = log_error_errno(EINVAL, "error taking over netlink socket");

goto exit;

}

/* get our own cgroup, we regularly kill everything udev has left behind */

if (cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, 0, &udev_cgroup) < 0)

udev_cgroup = NULL;

} else {

/* open control and netlink socket */

udev_ctrl = udev_ctrl_new(udev);

if (!udev_ctrl) {

r = log_error_errno(EINVAL, "error initializing udev control socket");

goto exit;

}

fd_ctrl = udev_ctrl_get_fd(udev_ctrl);

monitor = udev_monitor_new_from_netlink(udev, "kernel");

if (!monitor) {

r = log_error_errno(EINVAL, "error initializing netlink socket");

goto exit;

}

fd_netlink = udev_monitor_get_fd(monitor);

udev_monitor_set_receive_buffer_size(monitor, 128 * 1024 * 1024);

}

if (udev_monitor_enable_receiving(monitor) < 0) {

r = log_error_errno(EINVAL, "error binding netlink socket");

goto exit;

}

if (udev_ctrl_enable_receiving(udev_ctrl) < 0) {

r = log_error_errno(EINVAL, "error binding udev control socket");

goto exit;

}

log_info("starting version " VERSION);

udev_builtin_init(udev);

rules = udev_rules_new(udev, arg_resolve_names);

if (!rules) {

r = log_error_errno(ENOMEM, "error reading rules");

goto exit;

}

r = udev_rules_apply_static_dev_perms(rules);

if (r < 0)

log_error_errno(r, "failed to apply permissions on static device nodes: %m");

if (arg_daemonize) {

pid_t pid;

pid = fork();

switch (pid) {

case 0:

break;

case -1:

r = log_error_errno(errno, "fork of daemon failed: %m");

goto exit;

default:

goto exit_daemonize;

}

setsid();

write_string_file("/proc/self/oom_score_adj", "-1000");

} else {

sd_notify(1, "READY=1");

}

if (arg_children_max == 0) {

cpu_set_t cpu_set;

arg_children_max = 8;

if (sched_getaffinity(0, sizeof (cpu_set), &cpu_set) == 0) {

arg_children_max += CPU_COUNT(&cpu_set) * 2;

}

}

log_debug("set children_max to %u", arg_children_max);

udev_list_node_init(&event_list);

fd_inotify = udev_watch_init(udev);

if (fd_inotify < 0) {

r = log_error_errno(ENOMEM, "error initializing inotify");

goto exit;

}

udev_watch_restore(udev);

/* block and listen to all signals on signalfd */

sigfillset(&mask);

sigprocmask(SIG_SETMASK, &mask, &sigmask_orig);

fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);

if (fd_signal < 0) {

r = log_error_errno(errno, "error creating signalfd");

goto exit;

}

/* unnamed socket from workers to the main daemon */

if (socketpair(AF_LOCAL, SOCK_DGRAM|SOCK_CLOEXEC, 0, worker_watch) < 0) {

r = log_error_errno(errno, "error creating socketpair");

goto exit;

}

fd_worker = worker_watch[READ_END];

r = setsockopt(fd_worker, SOL_SOCKET, SO_PASSCRED, &one, sizeof(one));

if (r < 0)

return log_error_errno(errno, "could not enable SO_PASSCRED: %m");

ep_ctrl.data.fd = fd_ctrl;

ep_inotify.data.fd = fd_inotify;

ep_signal.data.fd = fd_signal;

ep_netlink.data.fd = fd_netlink;

ep_worker.data.fd = fd_worker;

fd_ep = epoll_create1(EPOLL_CLOEXEC);

if (fd_ep < 0) {

log_error_errno(errno, "error creating epoll fd: %m");

goto exit;

}

if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_ctrl, &ep_ctrl) < 0 ||

epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_inotify, &ep_inotify) < 0 ||

epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_signal, &ep_signal) < 0 ||

epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_netlink, &ep_netlink) < 0 ||

epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_worker, &ep_worker) < 0) {

log_error_errno(errno, "fail to add fds to epoll: %m");

goto exit;

}

for (;;) {

static usec_t last_usec;

struct epoll_event ev[8];

int fdcount;

int timeout;

bool is_worker, is_signal, is_inotify, is_netlink, is_ctrl;

int i;

if (udev_exit) {

/* close sources of new events and discard buffered events */

if (fd_ctrl >= 0) {

epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_ctrl, NULL);

fd_ctrl = -1;

}

if (monitor != NULL) {

epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_netlink, NULL);

udev_monitor_unref(monitor);

monitor = NULL;

}

if (fd_inotify >= 0) {

epoll_ctl(fd_ep, EPOLL_CTL_DEL, fd_inotify, NULL);

close(fd_inotify);

fd_inotify = -1;

}

/* discard queued events and kill workers */

event_queue_cleanup(udev, EVENT_QUEUED);

worker_kill();

/* exit after all has cleaned up */

if (udev_list_node_is_empty(&event_list) && hashmap_isempty(workers))

break;

/* timeout at exit for workers to finish */

timeout = 30 * MSEC_PER_SEC;

} else if (udev_list_node_is_empty(&event_list) && hashmap_isempty(workers)) {

/* we are idle */

timeout = -1;

/* cleanup possible left-over processes in our cgroup */

if (udev_cgroup)

cg_kill(SYSTEMD_CGROUP_CONTROLLER, udev_cgroup, SIGKILL, false, true, NULL);

} else {

/* kill idle or hanging workers */

timeout = 3 * MSEC_PER_SEC;

}

/* tell settle that we are busy or idle */

event_queue_update();

fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), timeout);

if (fdcount < 0)

continue;

if (fdcount == 0) {

struct worker *worker;

Iterator j;

/* timeout */

if (udev_exit) {

log_error("timeout, giving up waiting for workers to finish");

break;

}

/* kill idle workers */

if (udev_list_node_is_empty(&event_list)) {

log_debug("cleanup idle workers");

worker_kill();

}

/* check for hanging events */

HASHMAP_FOREACH(worker, workers, j) {

struct event *event = worker->event;

usec_t ts;

if (worker->state != WORKER_RUNNING)

continue;

assert(event);

ts = now(CLOCK_MONOTONIC);

if ((ts - event->start_usec) > arg_event_timeout_warn_usec) {

if ((ts - event->start_usec) > arg_event_timeout_usec) {

log_error("worker ["PID_FMT"] %s timeout; kill it", worker->pid, event->devpath);

kill(worker->pid, SIGKILL);

worker->state = WORKER_KILLED;

log_error("seq %llu '%s' killed", udev_device_get_seqnum(event->dev), event->devpath);

} else if (!event->warned) {

log_warning("worker ["PID_FMT"] %s is taking a long time", worker->pid, event->devpath);

event->warned = true;

}

}

}

}

is_worker = is_signal = is_inotify = is_netlink = is_ctrl = false;

for (i = 0; i < fdcount; i++) {

if (ev[i].data.fd == fd_worker && ev[i].events & EPOLLIN)

is_worker = true;

else if (ev[i].data.fd == fd_netlink && ev[i].events & EPOLLIN)

is_netlink = true;

else if (ev[i].data.fd == fd_signal && ev[i].events & EPOLLIN)

is_signal = true;

else if (ev[i].data.fd == fd_inotify && ev[i].events & EPOLLIN)

is_inotify = true;

else if (ev[i].data.fd == fd_ctrl && ev[i].events & EPOLLIN)

is_ctrl = true;

}

/* check for changed config, every 3 seconds at most */

if ((now(CLOCK_MONOTONIC) - last_usec) > 3 * USEC_PER_SEC) {

if (udev_rules_check_timestamp(rules))

reload = true;

if (udev_builtin_validate(udev))

reload = true;

last_usec = now(CLOCK_MONOTONIC);

}

/* reload requested, HUP signal received, rules changed, builtin changed */

if (reload) {

worker_kill();

rules = udev_rules_unref(rules);

udev_builtin_exit(udev);

reload = false;

}

/* event has finished */

if (is_worker)

on_worker(NULL, fd_worker, 0, NULL);

/* uevent from kernel */

if (is_netlink)

on_uevent(NULL, fd_netlink, 0, monitor);

/* start new events */

if (!udev_list_node_is_empty(&event_list) && !udev_exit && !stop_exec_queue) {

udev_builtin_init(udev);

if (rules == NULL)

rules = udev_rules_new(udev, arg_resolve_names);

if (rules != NULL)

event_queue_start(udev);

}

if (is_signal) {

struct signalfd_siginfo fdsi;

ssize_t size;

size = read(fd_signal, &fdsi, sizeof(struct signalfd_siginfo));

if (size == sizeof(struct signalfd_siginfo)) {

switch (fdsi.ssi_signo) {

case SIGINT:

case SIGTERM:

on_request_exit(NULL, &fdsi, NULL);

break;

case SIGHUP:

on_request_reload(NULL, &fdsi, NULL);

break;

case SIGCHLD:

on_sigchld(NULL, &fdsi, NULL);

break;

}

}

}

/* we are shutting down, the events below are not handled anymore */

if (udev_exit)

continue;

/* device node watch */

if (is_inotify)

on_inotify(NULL, fd_inotify, 0, udev);

/*

if (is_ctrl)

on_ctrl_msg(NULL, fd_ctrl, 0, udev_ctrl);

}

exit:

udev_ctrl_cleanup(udev_ctrl);

unlink("/run/udev/queue");

exit_daemonize:

if (fd_ep >= 0)

close(fd_ep);

workers_free();

event_queue_cleanup(udev, EVENT_UNDEF);

udev_rules_unref(rules);

udev_builtin_exit(udev);

if (fd_signal >= 0)

close(fd_signal);

if (worker_watch[READ_END] >= 0)

close(worker_watch[READ_END]);

if (worker_watch[WRITE_END] >= 0)

close(worker_watch[WRITE_END]);

udev_monitor_unref(monitor);

udev_ctrl_connection_unref(udev_ctrl_conn);

udev_ctrl_unref(udev_ctrl);

udev_list_cleanup(&properties_list);

mac_selinux_finish();

udev_unref(udev);

log_close();

return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;

}