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-rw-r--r--src/notify/notify.c288
1 files changed, 288 insertions, 0 deletions
diff --git a/src/notify/notify.c b/src/notify/notify.c
new file mode 100644
index 0000000..7b23e7b
--- /dev/null
+++ b/src/notify/notify.c
@@ -0,0 +1,288 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <errno.h>
+#include <getopt.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "sd-daemon.h"
+
+#include "alloc-util.h"
+#include "env-util.h"
+#include "format-util.h"
+#include "log.h"
+#include "main-func.h"
+#include "parse-util.h"
+#include "pretty-print.h"
+#include "string-util.h"
+#include "strv.h"
+#include "terminal-util.h"
+#include "time-util.h"
+#include "user-util.h"
+#include "util.h"
+
+static bool arg_ready = false;
+static pid_t arg_pid = 0;
+static const char *arg_status = NULL;
+static bool arg_booted = false;
+static uid_t arg_uid = UID_INVALID;
+static gid_t arg_gid = GID_INVALID;
+static bool arg_no_block = false;
+
+static int help(void) {
+ _cleanup_free_ char *link = NULL;
+ int r;
+
+ r = terminal_urlify_man("systemd-notify", "1", &link);
+ if (r < 0)
+ return log_oom();
+
+ printf("%s [OPTIONS...] [VARIABLE=VALUE...]\n"
+ "\n%sNotify the init system about service status updates.%s\n\n"
+ " -h --help Show this help\n"
+ " --version Show package version\n"
+ " --ready Inform the init system about service start-up completion\n"
+ " --pid[=PID] Set main PID of daemon\n"
+ " --uid=USER Set user to send from\n"
+ " --status=TEXT Set status text\n"
+ " --booted Check if the system was booted up with systemd\n"
+ " --no-block Do not wait until operation finished\n"
+ "\nSee the %s for details.\n",
+ program_invocation_short_name,
+ ansi_highlight(),
+ ansi_normal(),
+ link);
+
+ return 0;
+}
+
+static pid_t manager_pid(void) {
+ const char *e;
+ pid_t pid;
+ int r;
+
+ /* If we run as a service managed by systemd --user the $MANAGERPID environment variable points to
+ * the service manager's PID. */
+ e = getenv("MANAGERPID");
+ if (!e)
+ return 0;
+
+ r = parse_pid(e, &pid);
+ if (r < 0) {
+ log_warning_errno(r, "$MANAGERPID is set to an invalid PID, ignoring: %s", e);
+ return 0;
+ }
+
+ return pid;
+}
+
+static int parse_argv(int argc, char *argv[]) {
+
+ enum {
+ ARG_READY = 0x100,
+ ARG_VERSION,
+ ARG_PID,
+ ARG_STATUS,
+ ARG_BOOTED,
+ ARG_UID,
+ ARG_NO_BLOCK
+ };
+
+ static const struct option options[] = {
+ { "help", no_argument, NULL, 'h' },
+ { "version", no_argument, NULL, ARG_VERSION },
+ { "ready", no_argument, NULL, ARG_READY },
+ { "pid", optional_argument, NULL, ARG_PID },
+ { "status", required_argument, NULL, ARG_STATUS },
+ { "booted", no_argument, NULL, ARG_BOOTED },
+ { "uid", required_argument, NULL, ARG_UID },
+ { "no-block", no_argument, NULL, ARG_NO_BLOCK },
+ {}
+ };
+
+ int c, r;
+
+ assert(argc >= 0);
+ assert(argv);
+
+ while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0) {
+
+ switch (c) {
+
+ case 'h':
+ return help();
+
+ case ARG_VERSION:
+ return version();
+
+ case ARG_READY:
+ arg_ready = true;
+ break;
+
+ case ARG_PID:
+ if (isempty(optarg) || streq(optarg, "auto")) {
+ arg_pid = getppid();
+
+ if (arg_pid <= 1 ||
+ arg_pid == manager_pid()) /* Don't send from PID 1 or the service
+ * manager's PID (which might be distinct from
+ * 1, if we are a --user instance), that'd just
+ * be confusing for the service manager */
+ arg_pid = getpid();
+ } else if (streq(optarg, "parent"))
+ arg_pid = getppid();
+ else if (streq(optarg, "self"))
+ arg_pid = getpid();
+ else {
+ r = parse_pid(optarg, &arg_pid);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse PID %s.", optarg);
+ }
+
+ break;
+
+ case ARG_STATUS:
+ arg_status = optarg;
+ break;
+
+ case ARG_BOOTED:
+ arg_booted = true;
+ break;
+
+ case ARG_UID: {
+ const char *u = optarg;
+
+ r = get_user_creds(&u, &arg_uid, &arg_gid, NULL, NULL, 0);
+ if (r == -ESRCH) /* If the user doesn't exist, then accept it anyway as numeric */
+ r = parse_uid(u, &arg_uid);
+ if (r < 0)
+ return log_error_errno(r, "Can't resolve user %s: %m", optarg);
+
+ break;
+ }
+
+ case ARG_NO_BLOCK:
+ arg_no_block = true;
+ break;
+
+ case '?':
+ return -EINVAL;
+
+ default:
+ assert_not_reached();
+ }
+ }
+
+ if (optind >= argc &&
+ !arg_ready &&
+ !arg_status &&
+ !arg_pid &&
+ !arg_booted) {
+ help();
+ return -EINVAL;
+ }
+
+ return 1;
+}
+
+static int run(int argc, char* argv[]) {
+ _cleanup_free_ char *status = NULL, *cpid = NULL, *n = NULL;
+ _cleanup_strv_free_ char **final_env = NULL;
+ char* our_env[4];
+ unsigned i = 0;
+ pid_t source_pid;
+ int r;
+
+ log_show_color(true);
+ log_parse_environment();
+ log_open();
+
+ r = parse_argv(argc, argv);
+ if (r <= 0)
+ return r;
+
+ if (arg_booted) {
+ r = sd_booted();
+ if (r < 0)
+ log_debug_errno(r, "Failed to determine whether we are booted with systemd, assuming we aren't: %m");
+ else
+ log_debug("The system %s booted with systemd.", r ? "was" : "was not");
+
+ return r <= 0;
+ }
+
+ if (arg_ready)
+ our_env[i++] = (char*) "READY=1";
+
+ if (arg_status) {
+ status = strjoin("STATUS=", arg_status);
+ if (!status)
+ return log_oom();
+
+ our_env[i++] = status;
+ }
+
+ if (arg_pid > 0) {
+ if (asprintf(&cpid, "MAINPID="PID_FMT, arg_pid) < 0)
+ return log_oom();
+
+ our_env[i++] = cpid;
+ }
+
+ our_env[i++] = NULL;
+
+ final_env = strv_env_merge(our_env, argv + optind);
+ if (!final_env)
+ return log_oom();
+
+ if (strv_isempty(final_env))
+ return 0;
+
+ n = strv_join(final_env, "\n");
+ if (!n)
+ return log_oom();
+
+ /* If this is requested change to the requested UID/GID. Note that we only change the real UID here, and leave
+ the effective UID in effect (which is 0 for this to work). That's because we want the privileges to fake the
+ ucred data, and sd_pid_notify() uses the real UID for filling in ucred. */
+
+ if (arg_gid != GID_INVALID &&
+ setregid(arg_gid, GID_INVALID) < 0)
+ return log_error_errno(errno, "Failed to change GID: %m");
+
+ if (arg_uid != UID_INVALID &&
+ setreuid(arg_uid, UID_INVALID) < 0)
+ return log_error_errno(errno, "Failed to change UID: %m");
+
+ if (arg_pid > 0)
+ source_pid = arg_pid;
+ else {
+ /* Pretend the message originates from our parent, given that we are typically called from a
+ * shell script, i.e. we are not the main process of a service but only a child of it. */
+ source_pid = getppid();
+ if (source_pid <= 1 ||
+ source_pid == manager_pid()) /* safety check: don't claim we'd send anything from PID 1
+ * or the service manager itself */
+ source_pid = 0;
+ }
+ r = sd_pid_notify(source_pid, false, n);
+ if (r < 0)
+ return log_error_errno(r, "Failed to notify init system: %m");
+ if (r == 0)
+ return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP),
+ "No status data could be sent: $NOTIFY_SOCKET was not set");
+
+ if (!arg_no_block) {
+ r = sd_notify_barrier(0, 5 * USEC_PER_SEC);
+ if (r < 0)
+ return log_error_errno(r, "Failed to invoke barrier: %m");
+ if (r == 0)
+ return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP),
+ "No status data could be sent: $NOTIFY_SOCKET was not set");
+ }
+
+ return 0;
+}
+
+DEFINE_MAIN_FUNCTION_WITH_POSITIVE_FAILURE(run);