#include "config.h"
#include "launchd.h"
#include <sys/types.h>
#include <sys/queue.h>
#include <sys/event.h>
#include <sys/stat.h>
#include <sys/ucred.h>
#include <sys/fcntl.h>
#include <sys/un.h>
#include <sys/wait.h>
#include <sys/sysctl.h>
#include <sys/sockio.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/ioctl.h>
#include <sys/mount.h>
#include <sys/kern_event.h>
#include <sys/reboot.h>
#include <sys/socket.h>
#include <sys/syscall.h>
#include <net/if.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet6/nd6.h>
#include <ifaddrs.h>
#include <unistd.h>
#include <signal.h>
#include <errno.h>
#include <libgen.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <stdbool.h>
#include <paths.h>
#include <pwd.h>
#include <grp.h>
#include <ttyent.h>
#include <dlfcn.h>
#include <dirent.h>
#include <string.h>
#include <setjmp.h>
#include <spawn.h>
#include <sched.h>
#include <pthread.h>
#include <util.h>
#include <assumes.h>
#if HAVE_LIBAUDITD
#include <bsm/auditd_lib.h>
#include <bsm/audit_session.h>
#endif
#include "bootstrap.h"
#include "vproc.h"
#include "vproc_priv.h"
#include "vproc_internal.h"
#include "launch.h"
#include "launch_internal.h"
#include "runtime.h"
#include "core.h"
#include "ipc.h"
#define LAUNCHD_CONF ".launchd.conf"
extern char **environ;
static void pfsystem_callback(void *, struct kevent *);
static kq_callback kqpfsystem_callback = pfsystem_callback;
static void pid1_magic_init(void);
static void testfd_or_openfd(int fd, const char *path, int flags);
static bool get_network_state(void);
static void monitor_networking_state(void);
static void fatal_signal_handler(int sig, siginfo_t *si, void *uap);
static void handle_pid1_crashes_separately(void);
static void do_pid1_crash_diagnosis_mode(const char *msg);
static int basic_fork(void);
static bool do_pid1_crash_diagnosis_mode2(const char *msg);
static void *update_thread(void *nothing);
static void *crash_addr;
static pid_t crash_pid;
char *_launchd_database_dir;
char *_launchd_log_dir;
bool launchd_shutting_down;
bool network_up;
uid_t launchd_uid;
FILE *launchd_console = NULL;
int32_t launchd_sync_frequency = 30;
int
main(int argc, char *const *argv)
{
bool sflag = false;
int ch;
testfd_or_openfd(STDIN_FILENO, _PATH_DEVNULL, O_RDONLY);
testfd_or_openfd(STDOUT_FILENO, _PATH_DEVNULL, O_WRONLY);
testfd_or_openfd(STDERR_FILENO, _PATH_DEVNULL, O_WRONLY);
if (launchd_use_gmalloc) {
if (!getenv("DYLD_INSERT_LIBRARIES")) {
setenv("DYLD_INSERT_LIBRARIES", "/usr/lib/libgmalloc.dylib", 1);
setenv("MALLOC_STRICT_SIZE", "1", 1);
execv(argv[0], argv);
} else {
unsetenv("DYLD_INSERT_LIBRARIES");
unsetenv("MALLOC_STRICT_SIZE");
}
} else if (launchd_malloc_log_stacks) {
if (!getenv("MallocStackLogging")) {
setenv("MallocStackLogging", "1", 1);
execv(argv[0], argv);
} else {
unsetenv("MallocStackLogging");
}
}
while ((ch = getopt(argc, argv, "s")) != -1) {
switch (ch) {
case 's': sflag = true; break;
case '?':
default:
fprintf(stderr, "%s: ignoring unknown arguments\n", getprogname());
break;
}
}
if (getpid() != 1 && getppid() != 1) {
fprintf(stderr, "%s: This program is not meant to be run directly.\n", getprogname());
exit(EXIT_FAILURE);
}
launchd_runtime_init();
if (NULL == getenv("PATH")) {
setenv("PATH", _PATH_STDPATH, 1);
}
if (pid1_magic) {
pid1_magic_init();
int cfd = -1;
if ((cfd = open(_PATH_CONSOLE, O_WRONLY | O_NOCTTY)) != -1) {
_fd(cfd);
if (!(launchd_console = fdopen(cfd, "w"))) {
(void)close(cfd);
}
}
char *extra = "";
if (launchd_osinstaller) {
extra = " in the OS Installer";
} else if (sflag) {
extra = " in single-user mode";
}
launchd_syslog(LOG_NOTICE | LOG_CONSOLE, "*** launchd[1] has started up%s. ***", extra);
if (launchd_use_gmalloc) {
launchd_syslog(LOG_NOTICE | LOG_CONSOLE, "*** Using libgmalloc. ***");
}
if (launchd_verbose_boot) {
launchd_syslog(LOG_NOTICE | LOG_CONSOLE, "*** Verbose boot, will log to /dev/console. ***");
}
if (launchd_shutdown_debugging) {
launchd_syslog(LOG_NOTICE | LOG_CONSOLE, "*** Shutdown debugging is enabled. ***");
}
if (launchd_log_shutdown) {
launchd_syslog(LOG_NOTICE | LOG_CONSOLE, "*** Shutdown logging is enabled. ***");
}
if (launchd_log_perf) {
launchd_syslog(LOG_NOTICE | LOG_CONSOLE, "*** Performance logging is enabled. ***");
}
if (launchd_log_debug) {
launchd_syslog(LOG_NOTICE | LOG_CONSOLE, "*** Debug logging is enabled. ***");
}
handle_pid1_crashes_separately();
pthread_t t = NULL;
(void)osx_assumes_zero(pthread_create(&t, NULL, update_thread, NULL));
(void)osx_assumes_zero(pthread_detach(t));
launchd_flat_mach_namespace = false;
fflush(launchd_console);
} else {
launchd_uid = getuid();
launchd_var_available = true;
if (asprintf(&launchd_label, "com.apple.launchd.peruser.%u", launchd_uid) == 0) {
launchd_label = "com.apple.launchd.peruser.unknown";
}
struct passwd *pwent = getpwuid(launchd_uid);
if (pwent) {
launchd_username = strdup(pwent->pw_name);
} else {
launchd_username = "(unknown)";
}
if (asprintf(&_launchd_database_dir, LAUNCHD_DB_PREFIX "/com.apple.launchd.peruser.%u", launchd_uid) == 0) {
_launchd_database_dir = "";
}
if (asprintf(&_launchd_log_dir, LAUNCHD_LOG_PREFIX "/com.apple.launchd.peruser.%u", launchd_uid) == 0) {
_launchd_log_dir = "";
}
if (launchd_allow_global_dyld_envvars) {
launchd_syslog(LOG_WARNING, "Per-user launchd will allow DYLD_* environment variables in the global environment.");
}
ipc_server_init();
launchd_log_push();
auditinfo_addr_t auinfo;
if (posix_assumes_zero(getaudit_addr(&auinfo, sizeof(auinfo))) != -1) {
launchd_audit_session = auinfo.ai_asid;
launchd_syslog(LOG_DEBUG, "Our audit session ID is %i", launchd_audit_session);
}
launchd_audit_port = _audit_session_self();
vproc_transaction_begin(NULL);
vproc_transaction_end(NULL, NULL);
launchd_syslog(LOG_DEBUG, "Per-user launchd started (UID/username): %u/%s.", launchd_uid, launchd_username);
}
monitor_networking_state();
jobmgr_init(sflag);
launchd_runtime_init2();
launchd_runtime();
}
void
handle_pid1_crashes_separately(void)
{
struct sigaction fsa;
fsa.sa_sigaction = fatal_signal_handler;
fsa.sa_flags = SA_SIGINFO;
sigemptyset(&fsa.sa_mask);
(void)posix_assumes_zero(sigaction(SIGILL, &fsa, NULL));
(void)posix_assumes_zero(sigaction(SIGFPE, &fsa, NULL));
(void)posix_assumes_zero(sigaction(SIGBUS, &fsa, NULL));
(void)posix_assumes_zero(sigaction(SIGTRAP, &fsa, NULL));
(void)posix_assumes_zero(sigaction(SIGABRT, &fsa, NULL));
(void)posix_assumes_zero(sigaction(SIGSEGV, &fsa, NULL));
}
void *
update_thread(void *nothing __attribute__((unused)))
{
(void)posix_assumes_zero(setiopolicy_np(IOPOL_TYPE_DISK, IOPOL_SCOPE_THREAD, IOPOL_THROTTLE));
while (launchd_sync_frequency) {
sync();
sleep(launchd_sync_frequency);
}
launchd_syslog(LOG_DEBUG, "Update thread exiting.");
return NULL;
}
#define PID1_CRASH_LOGFILE "/var/log/launchd-pid1.crash"
static __attribute__((unused)) typeof(sync) *__junk_dyld_trick1 = sync;
static __attribute__((unused)) typeof(sleep) *__junk_dyld_trick2 = sleep;
static __attribute__((unused)) typeof(reboot) *__junk_dyld_trick3 = reboot;
void
do_pid1_crash_diagnosis_mode(const char *msg)
{
if (launchd_wsp) {
kill(launchd_wsp, SIGKILL);
sleep(3);
launchd_wsp = 0;
}
while (launchd_shutdown_debugging && !do_pid1_crash_diagnosis_mode2(msg)) {
sleep(1);
}
}
int
basic_fork(void)
{
int wstatus = 0;
pid_t p;
switch ((p = fork())) {
case -1:
launchd_syslog(LOG_ERR | LOG_CONSOLE, "Can't fork PID 1 copy for crash debugging: %m");
return p;
case 0:
return p;
default:
do {
(void)waitpid(p, &wstatus, 0);
} while(!WIFEXITED(wstatus));
fprintf(stdout, "PID 1 copy: exit status: %d\n", WEXITSTATUS(wstatus));
return 1;
}
return -1;
}
bool
do_pid1_crash_diagnosis_mode2(const char *msg)
{
if (basic_fork() == 0) {
if (launchd_console) {
fflush(launchd_console);
}
task_set_bootstrap_port(mach_task_self(), MACH_PORT_NULL);
if (basic_fork() != 0) {
if (launchd_console) {
fflush(launchd_console);
}
return true;
}
} else {
return true;
}
int fd;
revoke(_PATH_CONSOLE);
if ((fd = open(_PATH_CONSOLE, O_RDWR)) == -1) {
_exit(2);
}
if (login_tty(fd) == -1) {
_exit(3);
}
setenv("TERM", "vt100", 1);
fprintf(stdout, "\n");
fprintf(stdout, "Entering launchd PID 1 debugging mode...\n");
fprintf(stdout, "The PID 1 launchd has crashed %s.\n", msg);
fprintf(stdout, "It has fork(2)ed itself for debugging.\n");
fprintf(stdout, "To debug the crashing thread of PID 1:\n");
fprintf(stdout, " gdb attach %d\n", getppid());
fprintf(stdout, "To exit this shell and shut down:\n");
fprintf(stdout, " kill -9 1\n");
fprintf(stdout, "A sample of PID 1 has been written to %s\n", PID1_CRASH_LOGFILE);
fprintf(stdout, "\n");
fflush(stdout);
execl(_PATH_BSHELL, "-sh", NULL);
syslog(LOG_ERR, "can't exec %s for PID 1 crash debugging: %m", _PATH_BSHELL);
_exit(EXIT_FAILURE);
}
void
fatal_signal_handler(int sig, siginfo_t *si, void *uap __attribute__((unused)))
{
const char *doom_why = "at instruction";
char msg[128];
char *sample_args[] = { "/usr/bin/sample", "1", "1", "-file", PID1_CRASH_LOGFILE, NULL };
pid_t sample_p;
int wstatus;
crash_addr = si->si_addr;
crash_pid = si->si_pid;
setenv("XPC_SERVICES_UNAVAILABLE", "1", 0);
unlink(PID1_CRASH_LOGFILE);
switch ((sample_p = vfork())) {
case 0:
execve(sample_args[0], sample_args, environ);
_exit(EXIT_FAILURE);
break;
default:
waitpid(sample_p, &wstatus, 0);
break;
case -1:
break;
}
switch (sig) {
default:
case 0:
break;
case SIGBUS:
case SIGSEGV:
doom_why = "trying to read/write";
case SIGILL:
case SIGFPE:
snprintf(msg, sizeof(msg), "%s: %p (%s sent by PID %u)", doom_why, crash_addr, strsignal(sig), crash_pid);
sync();
do_pid1_crash_diagnosis_mode(msg);
sleep(3);
reboot(0);
break;
}
}
void
pid1_magic_init(void)
{
launchd_label = "com.apple.launchd";
launchd_username = "system";
_launchd_database_dir = LAUNCHD_DB_PREFIX "/com.apple.launchd";
_launchd_log_dir = LAUNCHD_LOG_PREFIX "/com.apple.launchd";
(void)posix_assumes_zero(setsid());
(void)posix_assumes_zero(chdir("/"));
(void)posix_assumes_zero(setlogin("root"));
#if !TARGET_OS_EMBEDDED
auditinfo_addr_t auinfo = {
.ai_termid = {
.at_type = AU_IPv4
},
.ai_asid = AU_ASSIGN_ASID,
.ai_auid = AU_DEFAUDITID,
.ai_flags = AU_SESSION_FLAG_IS_INITIAL,
};
if (setaudit_addr(&auinfo, sizeof(auinfo)) == -1) {
launchd_syslog(LOG_WARNING | LOG_CONSOLE, "Could not set audit session: %d: %s.", errno, strerror(errno));
_exit(EXIT_FAILURE);
}
launchd_audit_session = auinfo.ai_asid;
launchd_syslog(LOG_DEBUG, "Audit Session ID: %i", launchd_audit_session);
launchd_audit_port = _audit_session_self();
#endif // !TARGET_OS_EMBEDDED
}
char *
launchd_copy_persistent_store(int type, const char *file)
{
char *result = NULL;
if (!file) {
file = "";
}
switch (type) {
case LAUNCHD_PERSISTENT_STORE_DB:
(void)asprintf(&result, "%s/%s", _launchd_database_dir, file);
break;
case LAUNCHD_PERSISTENT_STORE_LOGS:
(void)asprintf(&result, "%s/%s", _launchd_log_dir, file);
break;
default:
break;
}
return result;
}
int
_fd(int fd)
{
if (fd >= 0) {
(void)posix_assumes_zero(fcntl(fd, F_SETFD, 1));
}
return fd;
}
void
launchd_shutdown(void)
{
int64_t now;
if (launchd_shutting_down) {
return;
}
runtime_ktrace0(RTKT_LAUNCHD_EXITING);
launchd_shutting_down = true;
launchd_log_push();
now = runtime_get_wall_time();
char *term_who = pid1_magic ? "System shutdown" : "Per-user launchd termination for ";
launchd_syslog(LOG_INFO, "%s%s began", term_who, pid1_magic ? "" : launchd_username);
osx_assert(jobmgr_shutdown(root_jobmgr) != NULL);
#if HAVE_LIBAUDITD
if (pid1_magic) {
(void)osx_assumes_zero(audit_quick_stop());
}
#endif
}
void
launchd_SessionCreate(void)
{
#if !TARGET_OS_EMBEDDED
auditinfo_addr_t auinfo = {
.ai_termid = { .at_type = AU_IPv4 },
.ai_asid = AU_ASSIGN_ASID,
.ai_auid = getuid(),
.ai_flags = 0,
};
if (setaudit_addr(&auinfo, sizeof(auinfo)) == 0) {
char session[16];
snprintf(session, sizeof(session), "%x", auinfo.ai_asid);
setenv("SECURITYSESSIONID", session, 1);
} else {
launchd_syslog(LOG_WARNING, "Could not set audit session: %d: %s.", errno, strerror(errno));
}
#endif // !TARGET_OS_EMBEDDED
}
void
testfd_or_openfd(int fd, const char *path, int flags)
{
int tmpfd;
if (-1 != (tmpfd = dup(fd))) {
(void)posix_assumes_zero(runtime_close(tmpfd));
} else {
if (-1 == (tmpfd = open(path, flags | O_NOCTTY, DEFFILEMODE))) {
launchd_syslog(LOG_ERR, "open(\"%s\", ...): %m", path);
} else if (tmpfd != fd) {
(void)posix_assumes_zero(dup2(tmpfd, fd));
(void)posix_assumes_zero(runtime_close(tmpfd));
}
}
}
bool
get_network_state(void)
{
struct ifaddrs *ifa, *ifai;
bool up = false;
int r;
while ((r = getifaddrs(&ifa)) == -1 && errno == ENOMEM) {
launchd_syslog(LOG_DEBUG, "Worked around bug: 4978696");
(void)posix_assumes_zero(sched_yield());
}
if (posix_assumes_zero(r) == -1) {
return network_up;
}
for (ifai = ifa; ifai; ifai = ifai->ifa_next) {
if (!(ifai->ifa_flags & IFF_UP)) {
continue;
}
if (ifai->ifa_flags & IFF_LOOPBACK) {
continue;
}
if (ifai->ifa_addr->sa_family != AF_INET && ifai->ifa_addr->sa_family != AF_INET6) {
continue;
}
up = true;
break;
}
freeifaddrs(ifa);
return up;
}
void
monitor_networking_state(void)
{
int pfs = _fd(socket(PF_SYSTEM, SOCK_RAW, SYSPROTO_EVENT));
struct kev_request kev_req;
network_up = get_network_state();
if (pfs == -1) {
(void)osx_assumes_zero(errno);
return;
}
memset(&kev_req, 0, sizeof(kev_req));
kev_req.vendor_code = KEV_VENDOR_APPLE;
kev_req.kev_class = KEV_NETWORK_CLASS;
if (posix_assumes_zero(ioctl(pfs, SIOCSKEVFILT, &kev_req)) == -1) {
runtime_close(pfs);
return;
}
(void)posix_assumes_zero(kevent_mod(pfs, EVFILT_READ, EV_ADD, 0, 0, &kqpfsystem_callback));
}
void
pfsystem_callback(void *obj __attribute__((unused)), struct kevent *kev)
{
bool new_networking_state;
char buf[1024];
(void)posix_assumes_zero(read((int)kev->ident, &buf, sizeof(buf)));
new_networking_state = get_network_state();
if (new_networking_state != network_up) {
network_up = new_networking_state;
jobmgr_dispatch_all_semaphores(root_jobmgr);
}
}