chiark / gitweb /
udevd: create standard symlinks and handle /lib/udev/devices
[elogind.git] / udev / udevd.c
index 2cdc18b41e45a3a831d044a80d027e50dbd39d31..1bde8f4a746d19b719d71289137e308e5721ae2f 100644 (file)
@@ -31,6 +31,7 @@
 #include <time.h>
 #include <getopt.h>
 #include <dirent.h>
+#include <sys/time.h>
 #include <sys/prctl.h>
 #include <sys/socket.h>
 #include <sys/signalfd.h>
@@ -53,8 +54,15 @@ static void log_fn(struct udev *udev, int priority,
                   const char *format, va_list args)
 {
        if (debug) {
-               fprintf(stderr, "[%d] %s: ", (int) getpid(), fn);
-               vfprintf(stderr, format, args);
+               char buf[1024];
+               struct timeval tv;
+               struct timezone tz;
+
+               vsnprintf(buf, sizeof(buf), format, args);
+               gettimeofday(&tv, &tz);
+               fprintf(stderr, "%llu.%06u [%u] %s: %s",
+                       (unsigned long long) tv.tv_sec, (unsigned int) tv.tv_usec,
+                       (int) getpid(), fn, buf);
        } else {
                vsyslog(priority, format, args);
        }
@@ -71,6 +79,7 @@ static bool stop_exec_queue;
 static bool reload_config;
 static int max_childs;
 static int childs;
+static sigset_t orig_sigmask;
 static struct udev_list_node event_list;
 static struct udev_list_node worker_list;
 static bool udev_exit;
@@ -109,6 +118,8 @@ struct event {
        const char *devpath;
        size_t devpath_len;
        const char *devpath_old;
+       dev_t devnum;
+       bool is_block;
 };
 
 static struct event *node_to_event(struct udev_list_node *node)
@@ -157,7 +168,7 @@ static void event_queue_delete(struct event *event)
        udev_list_node_remove(&event->node);
 
        /* mark as failed, if "add" event returns non-zero */
-       if (event->exitcode && strcmp(udev_device_get_action(event->dev), "add") == 0)
+       if (event->exitcode != 0 && strcmp(udev_device_get_action(event->dev), "remove") != 0)
                udev_queue_export_device_failed(udev_queue_export, event->dev);
        else
                udev_queue_export_device_finished(udev_queue_export, event->dev);
@@ -212,7 +223,6 @@ static void worker_new(struct event *event)
        /* 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);
-       util_set_fd_cloexec(udev_monitor_get_fd(worker_monitor));
 
        worker = calloc(1, sizeof(struct worker));
        if (worker == NULL)
@@ -263,9 +273,11 @@ static void worker_new(struct event *event)
 
                do {
                        struct udev_event *udev_event;
-                       struct worker_message msg;
+                       struct worker_message msg = {};
                        int err;
+                       int failed = 0;
 
+                       info(event->udev, "seq %llu running\n", udev_device_get_seqnum(dev));
                        udev_event = udev_event_new(dev);
                        if (udev_event == NULL)
                                _exit(3);
@@ -280,11 +292,9 @@ static void worker_new(struct event *event)
                        if (udev_device_get_event_timeout(dev) >= 0)
                                alarm(udev_device_get_event_timeout(dev));
 
-                       /* execute RUN= */
-                       if (err == 0 && !udev_event->ignore_device && udev_get_run(udev_event->udev))
-                               udev_event_execute_run(udev_event);
+                       if (err == 0)
+                               failed = udev_event_execute_run(udev_event, &orig_sigmask);
 
-                       /* reset alarm */
                        alarm(0);
 
                        /* apply/restore inotify watch */
@@ -296,8 +306,11 @@ static void worker_new(struct event *event)
                        /* send processed event back to libudev listeners */
                        udev_monitor_send_device(worker_monitor, NULL, dev);
 
-                       /* send back the result of the event execution */
-                       msg.exitcode = err;
+                       /* send udevd the result of the event execution */
+                       if (err != 0)
+                               msg.exitcode = err;
+                       else if (failed != 0)
+                               msg.exitcode = failed;
                        msg.pid = getpid();
                        send(worker_watch[WRITE_END], &msg, sizeof(struct worker_message), 0);
 
@@ -347,7 +360,7 @@ static void worker_new(struct event *event)
        }
 }
 
-static void event_run(struct event *event)
+static void event_run(struct event *event, bool force)
 {
        struct udev_list_node *loop;
 
@@ -372,7 +385,7 @@ static void event_run(struct event *event)
                return;
        }
 
-       if (childs >= max_childs) {
+       if (!force && childs >= max_childs) {
                info(event->udev, "maximum number (%i) of childs reached\n", childs);
                return;
        }
@@ -395,6 +408,8 @@ static void event_queue_insert(struct udev_device *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 = (strcmp("block", udev_device_get_subsystem(dev)) == 0);
 
        udev_queue_export_device_queued(udev_queue_export, dev);
        info(event->udev, "seq %llu queued, '%s' '%s'\n", udev_device_get_seqnum(dev),
@@ -405,7 +420,7 @@ static void event_queue_insert(struct udev_device *dev)
 
        /* run all events with a timeout set immediately */
        if (udev_device_get_timeout(dev) > 0) {
-               worker_new(event);
+               event_run(event, true);
                return;
        }
 }
@@ -434,31 +449,8 @@ static void worker_kill(struct udev *udev, int retain)
        }
 }
 
-static int mem_size_mb(void)
-{
-       FILE *f;
-       char buf[4096];
-       long int memsize = -1;
-
-       f = fopen("/proc/meminfo", "r");
-       if (f == NULL)
-               return -1;
-
-       while (fgets(buf, sizeof(buf), f) != NULL) {
-               long int value;
-
-               if (sscanf(buf, "MemTotal: %ld kB", &value) == 1) {
-                       memsize = value / 1024;
-                       break;
-               }
-       }
-
-       fclose(f);
-       return memsize;
-}
-
 /* lookup event for identical, parent, child device */
-static int devpath_busy(struct event *event)
+static bool is_devpath_busy(struct event *event)
 {
        struct udev_list_node *loop;
        size_t common;
@@ -473,18 +465,21 @@ static int devpath_busy(struct event *event)
 
                /* event we checked earlier still exists, no need to check again */
                if (loop_event->seqnum == event->delaying_seqnum)
-                       return 2;
+                       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 our old name */
-               if (event->devpath_old != NULL)
-                       if (strcmp(loop_event->devpath, event->devpath_old) == 0) {
-                               event->delaying_seqnum = loop_event->seqnum;
-                               return 3;
-                       }
+               if (event->devpath_old != NULL && strcmp(loop_event->devpath, event->devpath_old) == 0) {
+                       event->delaying_seqnum = loop_event->seqnum;
+                       return true;
+               }
 
                /* compare devpath */
                common = MIN(loop_event->devpath_len, event->devpath_len);
@@ -496,26 +491,26 @@ static int devpath_busy(struct event *event)
                /* identical device event found */
                if (loop_event->devpath_len == event->devpath_len) {
                        event->delaying_seqnum = loop_event->seqnum;
-                       return 4;
+                       return true;
                }
 
                /* parent device event found */
                if (event->devpath[common] == '/') {
                        event->delaying_seqnum = loop_event->seqnum;
-                       return 5;
+                       return true;
                }
 
                /* child device event found */
                if (loop_event->devpath[common] == '/') {
                        event->delaying_seqnum = loop_event->seqnum;
-                       return 6;
+                       return true;
                }
 
                /* no matching device */
                continue;
        }
 
-       return 0;
+       return false;
 }
 
 static void events_start(struct udev *udev)
@@ -529,12 +524,12 @@ static void events_start(struct udev *udev)
                        continue;
 
                /* do not start event if parent or child event is still running */
-               if (devpath_busy(event) != 0) {
+               if (is_devpath_busy(event)) {
                        dbg(udev, "delay seq %llu (%s)\n", event->seqnum, event->devpath);
                        continue;
                }
 
-               event_run(event);
+               event_run(event, false);
        }
 }
 
@@ -647,7 +642,7 @@ static void handle_ctrl_msg(struct udev_ctrl *uctrl)
 /* read inotify messages */
 static int handle_inotify(struct udev *udev)
 {
-       ssize_t nbytes, pos;
+       int nbytes, pos;
        char *buf;
        struct inotify_event *ev;
 
@@ -667,14 +662,21 @@ static int handle_inotify(struct udev *udev)
 
                ev = (struct inotify_event *)(buf + pos);
                if (ev->len) {
-                       dbg(udev, "inotify event: %x for %s\n", ev->mask, ev->name);
+                       const char *s;
+
+                       info(udev, "inotify event: %x for %s\n", ev->mask, ev->name);
+                       s = strstr(ev->name, ".rules");
+                       if (s == NULL)
+                               continue;
+                       if (strlen(s) != strlen(".rules"))
+                               continue;
                        reload_config = true;
                        continue;
                }
 
                dev = udev_watch_lookup(udev, ev->wd);
                if (dev != NULL) {
-                       dbg(udev, "inotify event: %x for %s\n", ev->mask, udev_device_get_devnode(dev));
+                       info(udev, "inotify event: %x for %s\n", ev->mask, udev_device_get_devnode(dev));
                        if (ev->mask & IN_CLOSE_WRITE) {
                                char filename[UTIL_PATH_SIZE];
                                int fd;
@@ -743,37 +745,135 @@ static void handle_signal(struct udev *udev, int signo)
        }
 }
 
-static void startup_log(struct udev *udev)
+static int copy_dir(struct udev *udev, DIR *dir_from, DIR *dir_to, int maxdepth)
+{
+       struct dirent *dent;
+
+       for (dent = readdir(dir_from); dent != NULL; dent = readdir(dir_from)) {
+               struct stat stats;
+
+               if (dent->d_name[0] == '.')
+                       continue;
+               if (fstatat(dirfd(dir_from), dent->d_name, &stats, AT_SYMLINK_NOFOLLOW) != 0)
+                       continue;
+
+               if (S_ISBLK(stats.st_mode) || S_ISCHR(stats.st_mode)) {
+                       udev_selinux_setfscreateconat(udev, dirfd(dir_to), dent->d_name, stats.st_mode & 0777);
+                       if (mknodat(dirfd(dir_to), dent->d_name, stats.st_mode, stats.st_rdev) == 0) {
+                               fchmodat(dirfd(dir_to), dent->d_name, stats.st_mode & 0777, 0);
+                               fchownat(dirfd(dir_to), dent->d_name, stats.st_uid, stats.st_gid, 0);
+                       } else {
+                               utimensat(dirfd(dir_to), dent->d_name, NULL, 0);
+                       }
+                       udev_selinux_resetfscreatecon(udev);
+               } else if (S_ISLNK(stats.st_mode)) {
+                       char target[UTIL_PATH_SIZE];
+                       ssize_t len;
+
+                       len = readlinkat(dirfd(dir_from), dent->d_name, target, sizeof(target));
+                       if (len <= 0 || len == (ssize_t)sizeof(target))
+                               continue;
+                       target[len] = '\0';
+                       udev_selinux_setfscreateconat(udev, dirfd(dir_to), dent->d_name, S_IFLNK);
+                       if (symlinkat(target, dirfd(dir_to), dent->d_name) < 0 && errno == EEXIST)
+                               utimensat(dirfd(dir_to), dent->d_name, NULL, AT_SYMLINK_NOFOLLOW);
+                       udev_selinux_resetfscreatecon(udev);
+               } else if (S_ISDIR(stats.st_mode)) {
+                       DIR *dir2_from, *dir2_to;
+
+                       if (maxdepth == 0)
+                               continue;
+
+                       udev_selinux_setfscreateconat(udev, dirfd(dir_to), dent->d_name, S_IFDIR|0755);
+                       mkdirat(dirfd(dir_to), dent->d_name, 0755);
+                       udev_selinux_resetfscreatecon(udev);
+
+                       dir2_to = fdopendir(openat(dirfd(dir_to), dent->d_name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC));
+                       if (dir2_to == NULL)
+                               continue;
+
+                       dir2_from = fdopendir(openat(dirfd(dir_from), dent->d_name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC));
+                       if (dir2_from == NULL) {
+                               closedir(dir2_to);
+                               continue;
+                       }
+
+                       copy_dir(udev, dir2_from, dir2_to, maxdepth-1);
+
+                       closedir(dir2_to);
+                       closedir(dir2_from);
+               }
+       }
+
+       return 0;
+}
+
+static void prepare_dev(struct udev *udev)
+{
+       struct stdlinks {
+               const char *link;
+               const char *target;
+       };
+       static const struct stdlinks stdlinks[] = {
+               { "core", "/proc/kcore" },
+               { "fd", "/proc/fd" },
+               { "stdin", "/proc/self/fd/0" },
+               { "stdout", "/proc/self/fd/1" },
+               { "stderr", "/proc/self/fd/2" },
+       };
+       unsigned int i;
+       DIR *dir_from, *dir_to;
+
+       dir_to = opendir(udev_get_dev_path(udev));
+       if (dir_to == NULL)
+               return;
+
+       /* create standard symlinks to /proc */
+       for (i = 0; i < ARRAY_SIZE(stdlinks); i++) {
+               udev_selinux_setfscreateconat(udev, dirfd(dir_to), stdlinks[i].link, S_IFLNK);
+               if (symlinkat(stdlinks[i].target, dirfd(dir_to), stdlinks[i].link) < 0 && errno == EEXIST)
+                       utimensat(dirfd(dir_to), stdlinks[i].link, NULL, AT_SYMLINK_NOFOLLOW);
+               udev_selinux_resetfscreatecon(udev);
+       }
+
+       /* copy content from /lib/udev/devices to /dev */
+       dir_from = opendir(LIBEXECDIR "/devices");
+       if (dir_from != NULL) {
+               copy_dir(udev, dir_from, dir_to, 8);
+               closedir(dir_from);
+       }
+
+       closedir(dir_to);
+}
+
+static int mem_size_mb(void)
 {
        FILE *f;
-       char path[UTIL_PATH_SIZE];
-       struct stat statbuf;
+       char buf[4096];
+       long int memsize = -1;
 
-       f = fopen("/dev/kmsg", "w");
-       if (f != NULL)
-               fprintf(f, "<6>udev: starting version " VERSION "\n");
+       f = fopen("/proc/meminfo", "r");
+       if (f == NULL)
+               return -1;
 
-       util_strscpyl(path, sizeof(path), udev_get_sys_path(udev), "/class/mem/null", NULL);
-       if (lstat(path, &statbuf) == 0 && S_ISDIR(statbuf.st_mode)) {
-               const char *depr_str =
-                       "udev: missing sysfs features; please update the kernel "
-                       "or disable the kernel's CONFIG_SYSFS_DEPRECATED option; "
-                       "udev may fail to work correctly";
-
-               if (f != NULL)
-                       fprintf(f, "<3>%s\n", depr_str);
-               err(udev, "%s\n", depr_str);
-               sleep(3);
+       while (fgets(buf, sizeof(buf), f) != NULL) {
+               long int value;
+
+               if (sscanf(buf, "MemTotal: %ld kB", &value) == 1) {
+                       memsize = value / 1024;
+                       break;
+               }
        }
 
-       if (f != NULL)
-               fclose(f);
+       fclose(f);
+       return memsize;
 }
 
 int main(int argc, char *argv[])
 {
        struct udev *udev;
        int fd;
+       FILE *f;
        sigset_t mask;
        const char *value;
        int daemonize = false;
@@ -859,6 +959,8 @@ int main(int argc, char *argv[])
        if (write(STDERR_FILENO, 0, 0) < 0)
                dup2(fd, STDERR_FILENO);
 
+       prepare_dev(udev);
+
        /* init control socket, bind() ensures, that only one udevd instance is running */
        udev_ctrl = udev_ctrl_new_from_socket(udev, UDEV_CTRL_SOCK_PATH);
        if (udev_ctrl == NULL) {
@@ -895,25 +997,32 @@ int main(int argc, char *argv[])
 
        if (udev_get_rules_path(udev) != NULL) {
                inotify_add_watch(pfd[FD_INOTIFY].fd, udev_get_rules_path(udev),
-                                 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
+                                 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
        } else {
                char filename[UTIL_PATH_SIZE];
+               struct stat statbuf;
 
                inotify_add_watch(pfd[FD_INOTIFY].fd, LIBEXECDIR "/rules.d",
-                                 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
+                                 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
                inotify_add_watch(pfd[FD_INOTIFY].fd, SYSCONFDIR "/udev/rules.d",
-                                 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
+                                 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
 
                /* watch dynamic rules directory */
                util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev/rules.d", NULL);
+               if (stat(filename, &statbuf) != 0) {
+                       util_create_path(udev, filename);
+                       udev_selinux_setfscreatecon(udev, filename, S_IFDIR|0755);
+                       mkdir(filename, 0755);
+                       udev_selinux_resetfscreatecon(udev);
+               }
                inotify_add_watch(pfd[FD_INOTIFY].fd, filename,
-                                 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
+                                 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
        }
        udev_watch_restore(udev);
 
        /* block and listen to all signals on signalfd */
        sigfillset(&mask);
-       sigprocmask(SIG_SETMASK, &mask, NULL);
+       sigprocmask(SIG_SETMASK, &mask, &orig_sigmask);
        pfd[FD_SIGNAL].fd = signalfd(-1, &mask, 0);
        if (pfd[FD_SIGNAL].fd < 0) {
                fprintf(stderr, "error getting signalfd\n");
@@ -923,14 +1032,13 @@ int main(int argc, char *argv[])
        }
 
        /* unnamed socket from workers to the main daemon */
-       if (socketpair(AF_LOCAL, SOCK_DGRAM, 0, worker_watch) < 0) {
+       if (socketpair(AF_LOCAL, SOCK_DGRAM|SOCK_CLOEXEC, 0, worker_watch) < 0) {
                fprintf(stderr, "error getting socketpair\n");
                err(udev, "error getting socketpair\n");
                rc = 6;
                goto exit;
        }
        pfd[FD_WORKER].fd = worker_watch[READ_END];
-       util_set_fd_cloexec(worker_watch[WRITE_END]);
 
        rules = udev_rules_new(udev, resolve_names);
        if (rules == NULL) {
@@ -961,7 +1069,11 @@ int main(int argc, char *argv[])
                }
        }
 
-       startup_log(udev);
+       f = fopen("/dev/kmsg", "w");
+       if (f != NULL) {
+               fprintf(f, "<6>udev: starting version " VERSION "\n");
+               fclose(f);
+       }
 
        /* redirect std{out,err} */
        if (!debug && !debug_trace) {