From 9c438bcac67197b685c57c2f6f1b59cdfbf7c9b2 Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Fri, 19 Jun 2009 17:37:18 +0200 Subject: daemon: strip all special suid/caps log from our startup code, we'll now rely on RealtimeKit for all high-priority/RT scheduling policy issues --- src/daemon/main.c | 197 +++++------------------------------------------------- 1 file changed, 15 insertions(+), 182 deletions(-) (limited to 'src/daemon/main.c') diff --git a/src/daemon/main.c b/src/daemon/main.c index 8058e122..4b2a1f8b 100644 --- a/src/daemon/main.c +++ b/src/daemon/main.c @@ -102,7 +102,6 @@ #include "dumpmodules.h" #include "caps.h" #include "ltdl-bind-now.h" -#include "polkit.h" #ifdef HAVE_LIBWRAP /* Only one instance of these variables */ @@ -381,9 +380,7 @@ int main(int argc, char *argv[]) { pa_mainloop *mainloop = NULL; char *s; int r = 0, retval = 1, d = 0; - pa_bool_t suid_root, real_root; pa_bool_t valid_pid_file = FALSE; - gid_t gid = (gid_t) -1; pa_bool_t ltdl_init = FALSE; int passed_fd = -1; const char *e; @@ -426,30 +423,6 @@ int main(int argc, char *argv[]) { } #endif -#ifdef HAVE_GETUID - real_root = getuid() == 0; - suid_root = !real_root && geteuid() == 0; -#else - real_root = FALSE; - suid_root = FALSE; -#endif - - if (!real_root) { - /* Drop all capabilities except CAP_SYS_NICE */ - pa_limit_caps(); - - /* Drop privileges, but keep CAP_SYS_NICE */ - pa_drop_root(); - - /* After dropping root, the effective set is reset, hence, - * let's raise it again */ - pa_limit_caps(); - - /* When capabilities are not supported we will not be able to - * acquire RT sched anymore. But yes, that's the way it is. It - * is just too risky tun let PA run as root all the time. */ - } - if ((e = getenv("PULSE_PASSED_FD"))) { passed_fd = atoi(e); @@ -457,15 +430,14 @@ int main(int argc, char *argv[]) { passed_fd = -1; } + /* We might be autospawned, in which case have no idea in which + * context we have been started. Let's cleanup our execution + * context as good as possible */ + pa_drop_root(); pa_close_all(passed_fd, -1); - pa_reset_sigs(-1); pa_unblock_sigs(-1); - /* At this point, we are a normal user, possibly with CAP_NICE if - * we were started SUID. If we are started as normal root, than we - * still are normal root. */ - setlocale(LC_ALL, ""); pa_init_i18n(); @@ -490,150 +462,6 @@ int main(int argc, char *argv[]) { pa_log_set_flags(PA_LOG_PRINT_TIME, PA_LOG_SET); pa_log_set_show_backtrace(conf->log_backtrace); - pa_log_debug("Started as real root: %s, suid root: %s", pa_yes_no(real_root), pa_yes_no(suid_root)); - - if (!real_root && pa_have_caps()) { -#ifdef HAVE_SYS_RESOURCE_H - struct rlimit rl; -#endif - pa_bool_t allow_high_priority = FALSE, allow_realtime = FALSE; - - /* Let's better not enable high prio or RT by default */ - - if (conf->high_priority && !allow_high_priority) { - if (pa_own_uid_in_group(PA_REALTIME_GROUP, &gid) > 0) { - pa_log_info(_("We're in the group '%s', allowing high-priority scheduling."), PA_REALTIME_GROUP); - allow_high_priority = TRUE; - } - } - - if (conf->realtime_scheduling && !allow_realtime) { - if (pa_own_uid_in_group(PA_REALTIME_GROUP, &gid) > 0) { - pa_log_info(_("We're in the group '%s', allowing real-time scheduling."), PA_REALTIME_GROUP); - allow_realtime = TRUE; - } - } - -#ifdef HAVE_POLKIT - if (conf->high_priority && !allow_high_priority) { - if (pa_polkit_check("org.pulseaudio.acquire-high-priority") > 0) { - pa_log_info(_("PolicyKit grants us acquire-high-priority privilege.")); - allow_high_priority = TRUE; - } else - pa_log_info(_("PolicyKit refuses acquire-high-priority privilege.")); - } - - if (conf->realtime_scheduling && !allow_realtime) { - if (pa_polkit_check("org.pulseaudio.acquire-real-time") > 0) { - pa_log_info(_("PolicyKit grants us acquire-real-time privilege.")); - allow_realtime = TRUE; - } else - pa_log_info(_("PolicyKit refuses acquire-real-time privilege.")); - } -#endif - - if (!allow_high_priority && !allow_realtime) { - - /* OK, there's no further need to keep CAP_NICE. Hence - * let's give it up early */ - - pa_drop_caps(); - } - -#ifdef RLIMIT_RTPRIO - if (getrlimit(RLIMIT_RTPRIO, &rl) >= 0) - if (rl.rlim_cur > 0) { - pa_log_info("RLIMIT_RTPRIO is set to %u, allowing real-time scheduling.", (unsigned) rl.rlim_cur); - allow_realtime = TRUE; - } -#endif -#ifdef RLIMIT_NICE - if (getrlimit(RLIMIT_NICE, &rl) >= 0) - if (rl.rlim_cur > 20 ) { - pa_log_info("RLIMIT_NICE is set to %u, allowing high-priority scheduling.", (unsigned) rl.rlim_cur); - allow_high_priority = TRUE; - } -#endif - - if ((conf->high_priority && !allow_high_priority) || - (conf->realtime_scheduling && !allow_realtime)) - pa_log_info(_("Called SUID root and real-time and/or high-priority scheduling was requested in the configuration. However, we lack the necessary privileges:\n" - "We are not in group '%s', PolicyKit refuse to grant us the requested privileges and we have no increase RLIMIT_NICE/RLIMIT_RTPRIO resource limits.\n" - "For enabling real-time/high-priority scheduling please acquire the appropriate PolicyKit privileges, or become a member of '%s', or increase the RLIMIT_NICE/RLIMIT_RTPRIO resource limits for this user."), - PA_REALTIME_GROUP, PA_REALTIME_GROUP); - - - if (!allow_realtime) - conf->realtime_scheduling = FALSE; - - if (!allow_high_priority) - conf->high_priority = FALSE; - } - -#ifdef HAVE_SYS_RESOURCE_H - /* Reset resource limits. If we are run as root (for system mode) - * this might end up increasing the limits, which is intended - * behaviour. For all other cases, i.e. started as normal user, or - * SUID root at this point we should have no CAP_SYS_RESOURCE and - * increasing the limits thus should fail. Which is, too, intended - * behaviour */ - - set_all_rlimits(conf); -#endif - - if (conf->high_priority && !pa_can_high_priority()) { - pa_log_info(_("High-priority scheduling enabled in configuration but not allowed by policy.")); - conf->high_priority = FALSE; - } - - if (conf->high_priority && (conf->cmd == PA_CMD_DAEMON || conf->cmd == PA_CMD_START)) - pa_raise_priority(conf->nice_level); - - pa_log_debug("Can realtime: %s, can high-priority: %s", pa_yes_no(pa_can_realtime()), pa_yes_no(pa_can_high_priority())); - - if (!real_root && pa_have_caps()) { - pa_bool_t drop; - - drop = (conf->cmd != PA_CMD_DAEMON && conf->cmd != PA_CMD_START) || !conf->realtime_scheduling; - -#ifdef RLIMIT_RTPRIO - if (!drop) { - struct rlimit rl; - /* At this point we still have CAP_NICE if we were loaded - * SUID root. If possible let's acquire RLIMIT_RTPRIO - * instead and give CAP_NICE up. */ - - if (getrlimit(RLIMIT_RTPRIO, &rl) >= 0) { - - if (rl.rlim_cur >= 9) - drop = TRUE; - else { - rl.rlim_max = rl.rlim_cur = 9; - - if (setrlimit(RLIMIT_RTPRIO, &rl) >= 0) { - pa_log_info(_("Successfully increased RLIMIT_RTPRIO")); - drop = TRUE; - } else - pa_log_warn(_("RLIMIT_RTPRIO failed: %s"), pa_cstrerror(errno)); - } - } - } -#endif - - if (drop) { - pa_log_info(_("Giving up CAP_NICE")); - pa_drop_caps(); - suid_root = FALSE; - } - } - - if (conf->realtime_scheduling && !pa_can_realtime()) { - pa_log_info(_("Real-time scheduling enabled in configuration but not allowed by policy.")); - conf->realtime_scheduling = FALSE; - } - - pa_log_debug("Can realtime: %s, can high-priority: %s", pa_yes_no(pa_can_realtime()), pa_yes_no(pa_can_high_priority())); - LTDL_SET_PRELOADED_SYMBOLS(); pa_ltdl_init(); ltdl_init = TRUE; @@ -718,9 +546,9 @@ int main(int argc, char *argv[]) { pa_assert(conf->cmd == PA_CMD_DAEMON || conf->cmd == PA_CMD_START); } - if (real_root && !conf->system_instance) + if (getuid() == 0 && !conf->system_instance) pa_log_warn(_("This program is not intended to be run as root (unless --system is specified).")); - else if (!real_root && conf->system_instance) { + else if (getuid() != 0 && conf->system_instance) { pa_log(_("Root privileges required.")); goto finish; } @@ -866,6 +694,13 @@ int main(int argc, char *argv[]) { pa_assert_se(chdir("/") == 0); umask(0022); +#ifdef HAVE_SYS_RESOURCE_H + set_all_rlimits(conf); +#endif + pa_rtclock_hrtimer_enable(); + + pa_raise_priority(conf->nice_level); + if (conf->system_instance) if (change_user() < 0) goto finish; @@ -914,8 +749,8 @@ int main(int argc, char *argv[]) { pa_xfree(s); if ((s = pa_session_id())) { - pa_log_info(_("Session ID is %s."), s); - pa_xfree(s); + pa_log_info(_("Session ID is %s."), s); + pa_xfree(s); } if (!(s = pa_get_runtime_dir())) @@ -962,8 +797,6 @@ int main(int argc, char *argv[]) { else pa_log_info(_("Dude, your kernel stinks! The chef's recommendation today is Linux with high-resolution timers enabled!")); - pa_rtclock_hrtimer_enable(); - #ifdef SIGRTMIN /* Valgrind uses SIGRTMAX. To easy debugging we don't use it here */ pa_rtsig_configure(SIGRTMIN, SIGRTMAX-1); -- cgit