diff options
Diffstat (limited to 'src/udev/udevd.c')
| -rw-r--r-- | src/udev/udevd.c | 408 |
1 files changed, 408 insertions, 0 deletions
diff --git a/src/udev/udevd.c b/src/udev/udevd.c new file mode 100644 index 0000000..2ed4282 --- /dev/null +++ b/src/udev/udevd.c @@ -0,0 +1,408 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright © 2004 Chris Friesen <chris_friesen@sympatico.ca> + * Copyright © 2009 Canonical Ltd. + * Copyright © 2009 Scott James Remnant <scott@netsplit.com> + */ + +#include <getopt.h> +#include <unistd.h> + +#include "sd-daemon.h" + +#include "env-file.h" +#include "errno-util.h" +#include "fd-util.h" +#include "mkdir.h" +#include "parse-util.h" +#include "pretty-print.h" +#include "proc-cmdline.h" +#include "process-util.h" +#include "rlimit-util.h" +#include "selinux-util.h" +#include "signal-util.h" +#include "syslog-util.h" +#include "udev-manager.h" +#include "udev-util.h" +#include "udevd.h" +#include "version.h" + +static bool arg_debug = false; +static int arg_daemonize = false; + +static int listen_fds(int *ret_ctrl, int *ret_netlink) { + int ctrl_fd = -EBADF, netlink_fd = -EBADF; + int fd, n; + + assert(ret_ctrl); + assert(ret_netlink); + + n = sd_listen_fds(true); + if (n < 0) + return n; + + for (fd = SD_LISTEN_FDS_START; fd < n + SD_LISTEN_FDS_START; fd++) { + if (sd_is_socket(fd, AF_UNIX, SOCK_SEQPACKET, -1) > 0) { + if (ctrl_fd >= 0) + return -EINVAL; + ctrl_fd = fd; + continue; + } + + if (sd_is_socket(fd, AF_NETLINK, SOCK_RAW, -1) > 0) { + if (netlink_fd >= 0) + return -EINVAL; + netlink_fd = fd; + continue; + } + + return -EINVAL; + } + + *ret_ctrl = ctrl_fd; + *ret_netlink = netlink_fd; + + return 0; +} + +static int manager_parse_udev_config(Manager *manager) { + _cleanup_free_ char *log_val = NULL, *children_max = NULL, *exec_delay = NULL, + *event_timeout = NULL, *resolve_names = NULL, *timeout_signal = NULL; + int r; + + assert(manager); + + r = parse_env_file(NULL, "/etc/udev/udev.conf", + "udev_log", &log_val, + "children_max", &children_max, + "exec_delay", &exec_delay, + "event_timeout", &event_timeout, + "resolve_names", &resolve_names, + "timeout_signal", &timeout_signal); + if (r == -ENOENT) + return 0; + if (r < 0) + return r; + + r = udev_set_max_log_level(log_val); + if (r < 0) + log_syntax(NULL, LOG_WARNING, "/etc/udev/udev.conf", 0, r, + "Failed to set udev log level '%s', ignoring: %m", log_val); + + if (children_max) { + r = safe_atou(children_max, &manager->children_max); + if (r < 0) + log_syntax(NULL, LOG_WARNING, "/etc/udev/udev.conf", 0, r, + "Failed to parse children_max=%s, ignoring: %m", children_max); + } + + if (exec_delay) { + r = parse_sec(exec_delay, &manager->exec_delay_usec); + if (r < 0) + log_syntax(NULL, LOG_WARNING, "/etc/udev/udev.conf", 0, r, + "Failed to parse exec_delay=%s, ignoring: %m", exec_delay); + } + + if (event_timeout) { + r = parse_sec(event_timeout, &manager->timeout_usec); + if (r < 0) + log_syntax(NULL, LOG_WARNING, "/etc/udev/udev.conf", 0, r, + "Failed to parse event_timeout=%s, ignoring: %m", event_timeout); + } + + if (resolve_names) { + ResolveNameTiming t; + + t = resolve_name_timing_from_string(resolve_names); + if (t < 0) + log_syntax(NULL, LOG_WARNING, "/etc/udev/udev.conf", 0, r, + "Failed to parse resolve_names=%s, ignoring.", resolve_names); + else + manager->resolve_name_timing = t; + } + + if (timeout_signal) { + r = signal_from_string(timeout_signal); + if (r < 0) + log_syntax(NULL, LOG_WARNING, "/etc/udev/udev.conf", 0, r, + "Failed to parse timeout_signal=%s, ignoring: %m", timeout_signal); + else + manager->timeout_signal = r; + } + + return 0; +} + +/* + * read the kernel command line, in case we need to get into debug mode + * udev.log_level=<level> syslog priority + * udev.children_max=<number of workers> events are fully serialized if set to 1 + * udev.exec_delay=<number of seconds> delay execution of every executed program + * udev.event_timeout=<number of seconds> seconds to wait before terminating an event + * udev.blockdev_read_only<=bool> mark all block devices read-only when they appear + */ +static int parse_proc_cmdline_item(const char *key, const char *value, void *data) { + Manager *manager = ASSERT_PTR(data); + int r; + + assert(key); + + if (proc_cmdline_key_streq(key, "udev.log_level") || + proc_cmdline_key_streq(key, "udev.log_priority")) { /* kept for backward compatibility */ + + if (proc_cmdline_value_missing(key, value)) + return 0; + + r = log_level_from_string(value); + if (r >= 0) + log_set_max_level(r); + + } else if (proc_cmdline_key_streq(key, "udev.event_timeout")) { + + if (proc_cmdline_value_missing(key, value)) + return 0; + + r = parse_sec(value, &manager->timeout_usec); + + } else if (proc_cmdline_key_streq(key, "udev.children_max")) { + + if (proc_cmdline_value_missing(key, value)) + return 0; + + r = safe_atou(value, &manager->children_max); + + } else if (proc_cmdline_key_streq(key, "udev.exec_delay")) { + + if (proc_cmdline_value_missing(key, value)) + return 0; + + r = parse_sec(value, &manager->exec_delay_usec); + + } else if (proc_cmdline_key_streq(key, "udev.timeout_signal")) { + + if (proc_cmdline_value_missing(key, value)) + return 0; + + r = signal_from_string(value); + if (r > 0) + manager->timeout_signal = r; + + } else if (proc_cmdline_key_streq(key, "udev.blockdev_read_only")) { + + if (!value) + manager->blockdev_read_only = true; + else { + r = parse_boolean(value); + if (r < 0) + log_warning_errno(r, "Failed to parse udev.blockdev-read-only argument, ignoring: %s", value); + else + manager->blockdev_read_only = r; + } + + if (manager->blockdev_read_only) + log_notice("All physical block devices will be marked read-only."); + + return 0; + + } else { + if (startswith(key, "udev.")) + log_warning("Unknown udev kernel command line option \"%s\", ignoring.", key); + + return 0; + } + + if (r < 0) + log_warning_errno(r, "Failed to parse \"%s=%s\", ignoring: %m", key, value); + + return 0; +} + +static int help(void) { + _cleanup_free_ char *link = NULL; + int r; + + r = terminal_urlify_man("systemd-udevd.service", "8", &link); + if (r < 0) + return log_oom(); + + printf("%s [OPTIONS...]\n\n" + "Rule-based manager for device events and files.\n\n" + " -h --help Print this message\n" + " -V --version Print version of the program\n" + " -d --daemon Detach and run in the background\n" + " -D --debug Enable debug output\n" + " -c --children-max=INT Set maximum number of workers\n" + " -e --exec-delay=SECONDS Seconds to wait before executing RUN=\n" + " -t --event-timeout=SECONDS Seconds to wait before terminating an event\n" + " -N --resolve-names=early|late|never\n" + " When to resolve users and groups\n" + "\nSee the %s for details.\n", + program_invocation_short_name, + link); + + return 0; +} + +static int parse_argv(int argc, char *argv[], Manager *manager) { + enum { + ARG_TIMEOUT_SIGNAL, + }; + + 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' }, + { "timeout-signal", required_argument, NULL, ARG_TIMEOUT_SIGNAL }, + {} + }; + + int c, r; + + assert(argc >= 0); + assert(argv); + assert(manager); + + while ((c = getopt_long(argc, argv, "c:de:Dt:N:hV", options, NULL)) >= 0) { + switch (c) { + + case 'd': + arg_daemonize = true; + break; + case 'c': + r = safe_atou(optarg, &manager->children_max); + if (r < 0) + log_warning_errno(r, "Failed to parse --children-max= value '%s', ignoring: %m", optarg); + break; + case 'e': + r = parse_sec(optarg, &manager->exec_delay_usec); + if (r < 0) + log_warning_errno(r, "Failed to parse --exec-delay= value '%s', ignoring: %m", optarg); + break; + case ARG_TIMEOUT_SIGNAL: + r = signal_from_string(optarg); + if (r <= 0) + log_warning_errno(r, "Failed to parse --timeout-signal= value '%s', ignoring: %m", optarg); + else + manager->timeout_signal = r; + + break; + case 't': + r = parse_sec(optarg, &manager->timeout_usec); + if (r < 0) + log_warning_errno(r, "Failed to parse --event-timeout= value '%s', ignoring: %m", optarg); + break; + case 'D': + arg_debug = true; + break; + case 'N': { + ResolveNameTiming t; + + t = resolve_name_timing_from_string(optarg); + if (t < 0) + log_warning("Invalid --resolve-names= value '%s', ignoring.", optarg); + else + manager->resolve_name_timing = t; + break; + } + case 'h': + return help(); + case 'V': + printf("%s\n", GIT_VERSION); + return 0; + case '?': + return -EINVAL; + default: + assert_not_reached(); + + } + } + + return 1; +} + +int run_udevd(int argc, char *argv[]) { + _cleanup_(manager_freep) Manager *manager = NULL; + int fd_ctrl = -EBADF, fd_uevent = -EBADF; + int r; + + log_set_target(LOG_TARGET_AUTO); + log_open(); + + manager = manager_new(); + if (!manager) + return log_oom(); + + manager_parse_udev_config(manager); + + log_parse_environment(); + log_open(); /* Done again to update after reading configuration. */ + + r = parse_argv(argc, argv, manager); + if (r <= 0) + return r; + + r = proc_cmdline_parse(parse_proc_cmdline_item, manager, PROC_CMDLINE_STRIP_RD_PREFIX); + if (r < 0) + log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m"); + + if (arg_debug) { + log_set_target(LOG_TARGET_CONSOLE); + log_set_max_level(LOG_DEBUG); + } + + r = must_be_root(); + if (r < 0) + return r; + + /* set umask before creating any file/directory */ + umask(022); + + r = mac_init(); + if (r < 0) + return r; + + /* Make sure we can have plenty fds (for example for pidfds) */ + (void) rlimit_nofile_bump(-1); + + r = RET_NERRNO(mkdir("/run/udev", 0755)); + if (r < 0 && r != -EEXIST) + return log_error_errno(r, "Failed to create /run/udev: %m"); + + r = listen_fds(&fd_ctrl, &fd_uevent); + if (r < 0) + return log_error_errno(r, "Failed to listen on fds: %m"); + + r = manager_init(manager, fd_ctrl, fd_uevent); + if (r < 0) + return log_error_errno(r, "Failed to create manager: %m"); + + if (arg_daemonize) { + pid_t pid; + + log_info("Starting systemd-udevd version " GIT_VERSION); + + /* connect /dev/null to stdin, stdout, stderr */ + if (log_get_max_level() < LOG_DEBUG) { + r = make_null_stdio(); + if (r < 0) + log_warning_errno(r, "Failed to redirect standard streams to /dev/null: %m"); + } + + pid = fork(); + if (pid < 0) + return log_error_errno(errno, "Failed to fork daemon: %m"); + if (pid > 0) + /* parent */ + return 0; + + /* child */ + (void) setsid(); + } + + return manager_main(manager); +} |