/* SPDX-License-Identifier: GPL-2.0-or-later */ #include #include #include "sd-device.h" #include "sd-event.h" #include "device-enumerator-private.h" #include "device-private.h" #include "device-util.h" #include "fd-util.h" #include "fileio.h" #include "path-util.h" #include "process-util.h" #include "set.h" #include "string-util.h" #include "strv.h" #include "udevadm.h" #include "udevadm-util.h" #include "udev-ctrl.h" #include "virt.h" static bool arg_verbose = false; static bool arg_dry_run = false; static bool arg_quiet = false; static bool arg_uuid = false; static int exec_list( sd_device_enumerator *e, sd_device_action_t action, Hashmap *settle_hashmap) { bool skip_uuid_logic = false; const char *action_str; sd_device *d; int r, ret = 0; action_str = device_action_to_string(action); FOREACH_DEVICE_AND_SUBSYSTEM(e, d) { sd_id128_t id = SD_ID128_NULL; const char *syspath; r = sd_device_get_syspath(d, &syspath); if (r < 0) { log_debug_errno(r, "Failed to get syspath of enumerated devices, ignoring: %m"); continue; } if (arg_verbose) printf("%s\n", syspath); if (arg_dry_run) continue; /* Use the UUID mode if the user explicitly asked for it, or if --settle has been specified, * so that we can recognize our own uevent. */ r = sd_device_trigger_with_uuid(d, action, (arg_uuid || settle_hashmap) && !skip_uuid_logic ? &id : NULL); if (r == -EINVAL && !arg_uuid && settle_hashmap && !skip_uuid_logic) { /* If we specified a UUID because of the settling logic, and we got EINVAL this might * be caused by an old kernel which doesn't know the UUID logic (pre-4.13). Let's try * if it works without the UUID logic then. */ r = sd_device_trigger(d, action); if (r != -EINVAL) skip_uuid_logic = true; /* dropping the uuid stuff changed the return code, * hence don't bother next time */ } if (r < 0) { /* ENOENT may be returned when a device does not have /uevent or is already * removed. Hence, this is logged at debug level and ignored. * * ENODEV may be returned by some buggy device drivers e.g. /sys/devices/vio. * See, * https://github.com/systemd/systemd/issues/13652#issuecomment-535129791 and * https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1845319. * So, this error is ignored, but logged at warning level to encourage people to * fix the driver. * * EROFS is returned when /sys is read only. In that case, all subsequent * writes will also fail, hence return immediately. * * EACCES or EPERM may be returned when this is invoked by non-priviledged user. * We do NOT return immediately, but continue operation and propagate the error. * Why? Some device can be owned by a user, e.g., network devices configured in * a network namespace. See, https://github.com/systemd/systemd/pull/18559 and * https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ebb4a4bf76f164457184a3f43ebc1552416bc823 * * All other errors are logged at error level, but let's continue the operation, * and propagate the error. */ bool ignore = IN_SET(r, -ENOENT, -ENODEV); int level = arg_quiet ? LOG_DEBUG : r == -ENOENT ? LOG_DEBUG : r == -ENODEV ? LOG_WARNING : LOG_ERR; log_device_full_errno(d, level, r, "Failed to write '%s' to '%s/uevent'%s: %m", action_str, syspath, ignore ? ", ignoring" : ""); if (r == -EROFS) return r; if (ret == 0 && !ignore) ret = r; continue; } /* If the user asked for it, write event UUID to stdout */ if (arg_uuid) printf(SD_ID128_UUID_FORMAT_STR "\n", SD_ID128_FORMAT_VAL(id)); if (settle_hashmap) { _cleanup_free_ sd_id128_t *mid = NULL; _cleanup_free_ char *sp = NULL; sp = strdup(syspath); if (!sp) return log_oom(); mid = newdup(sd_id128_t, &id, 1); if (!d) return log_oom(); r = hashmap_put(settle_hashmap, sp, mid); if (r < 0) return log_oom(); TAKE_PTR(sp); TAKE_PTR(mid); } } return ret; } static int device_monitor_handler(sd_device_monitor *m, sd_device *dev, void *userdata) { Hashmap *settle_hashmap = userdata; sd_id128_t *settle_id; const char *syspath; char *k; int r; assert(dev); assert(settle_hashmap); r = sd_device_get_syspath(dev, &syspath); if (r < 0) { log_debug_errno(r, "Failed to get syspath of device event, ignoring: %m"); return 0; } settle_id = hashmap_get2(settle_hashmap, syspath, (void**) &k); if (!settle_id) { log_debug("Got uevent for unexpected device '%s', ignoring.", syspath); return 0; } if (!sd_id128_is_null(*settle_id)) { /* If this is SD_ID128_NULL then we are on pre-4.13 and have no UUID to check, hence don't */ sd_id128_t event_id; r = sd_device_get_trigger_uuid(dev, &event_id); if (r < 0) { log_debug_errno(r, "Got uevent without synthetic UUID for device '%s', ignoring: %m", syspath); return 0; } if (!sd_id128_equal(event_id, *settle_id)) { log_debug("Got uevent not matching expected UUID for device '%s', ignoring.", syspath); return 0; } } if (arg_verbose) printf("settle %s\n", syspath); if (arg_uuid) printf("settle " SD_ID128_UUID_FORMAT_STR "\n", SD_ID128_FORMAT_VAL(*settle_id)); free(hashmap_remove(settle_hashmap, syspath)); free(k); if (hashmap_isempty(settle_hashmap)) return sd_event_exit(sd_device_monitor_get_event(m), 0); return 0; } static char* keyval(const char *str, const char **key, const char **val) { char *buf, *pos; buf = strdup(str); if (!buf) return NULL; pos = strchr(buf, '='); if (pos) { pos[0] = 0; pos++; } *key = buf; *val = pos; return buf; } static int help(void) { printf("%s trigger [OPTIONS] DEVPATH\n\n" "Request events from the kernel.\n\n" " -h --help Show this help\n" " -V --version Show package version\n" " -v --verbose Print the list of devices while running\n" " -n --dry-run Do not actually trigger the events\n" " -q --quiet Suppress error logging in triggering events\n" " -t --type= Type of events to trigger\n" " devices sysfs devices (default)\n" " subsystems sysfs subsystems and drivers\n" " -c --action=ACTION|help Event action value, default is \"change\"\n" " -s --subsystem-match=SUBSYSTEM Trigger devices from a matching subsystem\n" " -S --subsystem-nomatch=SUBSYSTEM Exclude devices from a matching subsystem\n" " -a --attr-match=FILE[=VALUE] Trigger devices with a matching attribute\n" " -A --attr-nomatch=FILE[=VALUE] Exclude devices with a matching attribute\n" " -p --property-match=KEY=VALUE Trigger devices with a matching property\n" " -g --tag-match=TAG Trigger devices with a matching tag\n" " -y --sysname-match=NAME Trigger devices with this /sys path\n" " --name-match=NAME Trigger devices with this /dev name\n" " -b --parent-match=NAME Trigger devices with that parent device\n" " -w --settle Wait for the triggered events to complete\n" " --wait-daemon[=SECONDS] Wait for udevd daemon to be initialized\n" " before triggering uevents\n" " --uuid Print synthetic uevent UUID\n", program_invocation_short_name); return 0; } int trigger_main(int argc, char *argv[], void *userdata) { enum { ARG_NAME = 0x100, ARG_PING, ARG_UUID, }; static const struct option options[] = { { "verbose", no_argument, NULL, 'v' }, { "dry-run", no_argument, NULL, 'n' }, { "quiet", no_argument, NULL, 'q' }, { "type", required_argument, NULL, 't' }, { "action", required_argument, NULL, 'c' }, { "subsystem-match", required_argument, NULL, 's' }, { "subsystem-nomatch", required_argument, NULL, 'S' }, { "attr-match", required_argument, NULL, 'a' }, { "attr-nomatch", required_argument, NULL, 'A' }, { "property-match", required_argument, NULL, 'p' }, { "tag-match", required_argument, NULL, 'g' }, { "sysname-match", required_argument, NULL, 'y' }, { "name-match", required_argument, NULL, ARG_NAME }, { "parent-match", required_argument, NULL, 'b' }, { "settle", no_argument, NULL, 'w' }, { "wait-daemon", optional_argument, NULL, ARG_PING }, { "version", no_argument, NULL, 'V' }, { "help", no_argument, NULL, 'h' }, { "uuid", no_argument, NULL, ARG_UUID }, {} }; enum { TYPE_DEVICES, TYPE_SUBSYSTEMS, } device_type = TYPE_DEVICES; sd_device_action_t action = SD_DEVICE_CHANGE; _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL; _cleanup_(sd_device_monitor_unrefp) sd_device_monitor *m = NULL; _cleanup_(sd_event_unrefp) sd_event *event = NULL; _cleanup_hashmap_free_ Hashmap *settle_hashmap = NULL; usec_t ping_timeout_usec = 5 * USEC_PER_SEC; bool settle = false, ping = false; int c, r; if (running_in_chroot() > 0) { log_info("Running in chroot, ignoring request."); return 0; } r = sd_device_enumerator_new(&e); if (r < 0) return r; r = sd_device_enumerator_allow_uninitialized(e); if (r < 0) return r; while ((c = getopt_long(argc, argv, "vnqt:c:s:S:a:A:p:g:y:b:wVh", options, NULL)) >= 0) { _cleanup_free_ char *buf = NULL; const char *key, *val; switch (c) { case 'v': arg_verbose = true; break; case 'n': arg_dry_run = true; break; case 'q': arg_quiet = true; break; case 't': if (streq(optarg, "devices")) device_type = TYPE_DEVICES; else if (streq(optarg, "subsystems")) device_type = TYPE_SUBSYSTEMS; else return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Unknown type --type=%s", optarg); break; case 'c': { if (streq(optarg, "help")) { dump_device_action_table(); return 0; } action = device_action_from_string(optarg); if (action < 0) return log_error_errno(action, "Unknown action '%s'", optarg); break; } case 's': r = sd_device_enumerator_add_match_subsystem(e, optarg, true); if (r < 0) return log_error_errno(r, "Failed to add subsystem match '%s': %m", optarg); break; case 'S': r = sd_device_enumerator_add_match_subsystem(e, optarg, false); if (r < 0) return log_error_errno(r, "Failed to add negative subsystem match '%s': %m", optarg); break; case 'a': buf = keyval(optarg, &key, &val); if (!buf) return log_oom(); r = sd_device_enumerator_add_match_sysattr(e, key, val, true); if (r < 0) return log_error_errno(r, "Failed to add sysattr match '%s=%s': %m", key, val); break; case 'A': buf = keyval(optarg, &key, &val); if (!buf) return log_oom(); r = sd_device_enumerator_add_match_sysattr(e, key, val, false); if (r < 0) return log_error_errno(r, "Failed to add negative sysattr match '%s=%s': %m", key, val); break; case 'p': buf = keyval(optarg, &key, &val); if (!buf) return log_oom(); r = sd_device_enumerator_add_match_property(e, key, val); if (r < 0) return log_error_errno(r, "Failed to add property match '%s=%s': %m", key, val); break; case 'g': r = sd_device_enumerator_add_match_tag(e, optarg); if (r < 0) return log_error_errno(r, "Failed to add tag match '%s': %m", optarg); break; case 'y': r = sd_device_enumerator_add_match_sysname(e, optarg); if (r < 0) return log_error_errno(r, "Failed to add sysname match '%s': %m", optarg); break; case 'b': { _cleanup_(sd_device_unrefp) sd_device *dev = NULL; r = find_device(optarg, "/sys", &dev); if (r < 0) return log_error_errno(r, "Failed to open the device '%s': %m", optarg); r = device_enumerator_add_match_parent_incremental(e, dev); if (r < 0) return log_error_errno(r, "Failed to add parent match '%s': %m", optarg); break; } case 'w': settle = true; break; case ARG_NAME: { _cleanup_(sd_device_unrefp) sd_device *dev = NULL; r = find_device(optarg, "/dev/", &dev); if (r < 0) return log_error_errno(r, "Failed to open the device '%s': %m", optarg); r = device_enumerator_add_match_parent_incremental(e, dev); if (r < 0) return log_error_errno(r, "Failed to add parent match '%s': %m", optarg); break; } case ARG_PING: ping = true; if (optarg) { r = parse_sec(optarg, &ping_timeout_usec); if (r < 0) log_error_errno(r, "Failed to parse timeout value '%s', ignoring: %m", optarg); } break; case ARG_UUID: arg_uuid = true; break; case 'V': return print_version(); case 'h': return help(); case '?': return -EINVAL; default: assert_not_reached(); } } if (ping) { _cleanup_(udev_ctrl_unrefp) struct udev_ctrl *uctrl = NULL; r = udev_ctrl_new(&uctrl); if (r < 0) return log_error_errno(r, "Failed to initialize udev control: %m"); r = udev_ctrl_send_ping(uctrl); if (r < 0) return log_error_errno(r, "Failed to connect to udev daemon: %m"); r = udev_ctrl_wait(uctrl, ping_timeout_usec); if (r < 0) return log_error_errno(r, "Failed to wait for daemon to reply: %m"); } for (; optind < argc; optind++) { _cleanup_(sd_device_unrefp) sd_device *dev = NULL; r = find_device(argv[optind], NULL, &dev); if (r < 0) return log_error_errno(r, "Failed to open the device '%s': %m", argv[optind]); r = device_enumerator_add_match_parent_incremental(e, dev); if (r < 0) return log_error_errno(r, "Failed to add parent match '%s': %m", argv[optind]); } if (settle) { settle_hashmap = hashmap_new(&path_hash_ops_free_free); if (!settle_hashmap) return log_oom(); r = sd_event_default(&event); if (r < 0) return log_error_errno(r, "Failed to get default event: %m"); r = sd_device_monitor_new(&m); if (r < 0) return log_error_errno(r, "Failed to create device monitor object: %m"); r = sd_device_monitor_attach_event(m, event); if (r < 0) return log_error_errno(r, "Failed to attach event to device monitor: %m"); r = sd_device_monitor_start(m, device_monitor_handler, settle_hashmap); if (r < 0) return log_error_errno(r, "Failed to start device monitor: %m"); } switch (device_type) { case TYPE_SUBSYSTEMS: r = device_enumerator_scan_subsystems(e); if (r < 0) return log_error_errno(r, "Failed to scan subsystems: %m"); break; case TYPE_DEVICES: r = device_enumerator_scan_devices(e); if (r < 0) return log_error_errno(r, "Failed to scan devices: %m"); break; default: assert_not_reached(); } r = exec_list(e, action, settle_hashmap); if (r < 0) return r; if (event && !hashmap_isempty(settle_hashmap)) { r = sd_event_loop(event); if (r < 0) return log_error_errno(r, "Event loop failed: %m"); } return 0; }