diff options
Diffstat (limited to 'src/grp-resolve/systemd-resolved/resolved.c')
-rw-r--r-- | src/grp-resolve/systemd-resolved/resolved.c | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/src/grp-resolve/systemd-resolved/resolved.c b/src/grp-resolve/systemd-resolved/resolved.c new file mode 100644 index 0000000000..7fe9b7edbb --- /dev/null +++ b/src/grp-resolve/systemd-resolved/resolved.c @@ -0,0 +1,121 @@ +/*** + This file is part of systemd. + + Copyright 2014 Tom Gundersen <teg@jklm.no> + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 of the License, or + (at your option) any later version. + + systemd is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +#include <systemd/sd-daemon.h> +#include <systemd/sd-event.h> + +#include "systemd-basic/capability-util.h" +#include "systemd-basic/mkdir.h" +#include "systemd-basic/selinux-util.h" +#include "systemd-basic/signal-util.h" +#include "systemd-basic/user-util.h" + +#include "resolved-conf.h" +#include "resolved-manager.h" +#include "resolved-resolv-conf.h" + +int main(int argc, char *argv[]) { + _cleanup_(manager_freep) Manager *m = NULL; + const char *user = "systemd-resolve"; + uid_t uid; + gid_t gid; + int r; + + log_set_target(LOG_TARGET_AUTO); + log_parse_environment(); + log_open(); + + if (argc != 1) { + log_error("This program takes no arguments."); + r = -EINVAL; + goto finish; + } + + umask(0022); + + r = mac_selinux_init(); + if (r < 0) { + log_error_errno(r, "SELinux setup failed: %m"); + goto finish; + } + + r = get_user_creds(&user, &uid, &gid, NULL, NULL); + if (r < 0) { + log_error_errno(r, "Cannot resolve user name %s: %m", user); + goto finish; + } + + /* Always create the directory where resolv.conf will live */ + r = mkdir_safe_label("/run/systemd/resolve", 0755, uid, gid); + if (r < 0) { + log_error_errno(r, "Could not create runtime directory: %m"); + goto finish; + } + + /* Drop privileges, but keep three caps. Note that we drop those too, later on (see below) */ + r = drop_privileges(uid, gid, + (UINT64_C(1) << CAP_NET_RAW)| /* needed for SO_BINDTODEVICE */ + (UINT64_C(1) << CAP_NET_BIND_SERVICE)| /* needed to bind on port 53 */ + (UINT64_C(1) << CAP_SETPCAP) /* needed in order to drop the caps later */); + if (r < 0) + goto finish; + + assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGTERM, SIGINT, SIGUSR1, SIGUSR2, -1) >= 0); + + r = manager_new(&m); + if (r < 0) { + log_error_errno(r, "Could not create manager: %m"); + goto finish; + } + + r = manager_start(m); + if (r < 0) { + log_error_errno(r, "Failed to start manager: %m"); + goto finish; + } + + /* Write finish default resolv.conf to avoid a dangling symlink */ + (void) manager_write_resolv_conf(m); + + /* Let's drop the remaining caps now */ + r = capability_bounding_set_drop(0, true); + if (r < 0) { + log_error_errno(r, "Failed to drop remaining caps: %m"); + goto finish; + } + + sd_notify(false, + "READY=1\n" + "STATUS=Processing requests..."); + + r = sd_event_loop(m->event); + if (r < 0) { + log_error_errno(r, "Event loop failed: %m"); + goto finish; + } + + sd_event_get_exit_code(m->event, &r); + +finish: + sd_notify(false, + "STOPPING=1\n" + "STATUS=Shutting down..."); + + return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS; +} |