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-rw-r--r--src/execute.c1619
1 files changed, 1619 insertions, 0 deletions
diff --git a/src/execute.c b/src/execute.c
new file mode 100644
index 0000000000..12f514504c
--- /dev/null
+++ b/src/execute.c
@@ -0,0 +1,1619 @@
+/*-*- Mode: C; c-basic-offset: 8 -*-*/
+
+/***
+ This file is part of systemd.
+
+ Copyright 2010 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 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
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <assert.h>
+#include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <string.h>
+#include <signal.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <sys/prctl.h>
+#include <linux/sched.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <grp.h>
+#include <pwd.h>
+#include <sys/mount.h>
+#include <linux/fs.h>
+
+#include "execute.h"
+#include "strv.h"
+#include "macro.h"
+#include "util.h"
+#include "log.h"
+#include "ioprio.h"
+#include "securebits.h"
+#include "cgroup.h"
+#include "namespace.h"
+
+/* This assumes there is a 'tty' group */
+#define TTY_MODE 0620
+
+static int shift_fds(int fds[], unsigned n_fds) {
+ int start, restart_from;
+
+ if (n_fds <= 0)
+ return 0;
+
+ /* Modifies the fds array! (sorts it) */
+
+ assert(fds);
+
+ start = 0;
+ for (;;) {
+ int i;
+
+ restart_from = -1;
+
+ for (i = start; i < (int) n_fds; i++) {
+ int nfd;
+
+ /* Already at right index? */
+ if (fds[i] == i+3)
+ continue;
+
+ if ((nfd = fcntl(fds[i], F_DUPFD, i+3)) < 0)
+ return -errno;
+
+ close_nointr_nofail(fds[i]);
+ fds[i] = nfd;
+
+ /* Hmm, the fd we wanted isn't free? Then
+ * let's remember that and try again from here*/
+ if (nfd != i+3 && restart_from < 0)
+ restart_from = i;
+ }
+
+ if (restart_from < 0)
+ break;
+
+ start = restart_from;
+ }
+
+ return 0;
+}
+
+static int flags_fds(const int fds[], unsigned n_fds, bool nonblock) {
+ unsigned i;
+ int r;
+
+ if (n_fds <= 0)
+ return 0;
+
+ assert(fds);
+
+ /* Drops/Sets O_NONBLOCK and FD_CLOEXEC from the file flags */
+
+ for (i = 0; i < n_fds; i++) {
+
+ if ((r = fd_nonblock(fds[i], nonblock)) < 0)
+ return r;
+
+ /* We unconditionally drop FD_CLOEXEC from the fds,
+ * since after all we want to pass these fds to our
+ * children */
+
+ if ((r = fd_cloexec(fds[i], false)) < 0)
+ return r;
+ }
+
+ return 0;
+}
+
+static const char *tty_path(const ExecContext *context) {
+ assert(context);
+
+ if (context->tty_path)
+ return context->tty_path;
+
+ return "/dev/console";
+}
+
+static int open_null_as(int flags, int nfd) {
+ int fd, r;
+
+ assert(nfd >= 0);
+
+ if ((fd = open("/dev/null", flags|O_NOCTTY)) < 0)
+ return -errno;
+
+ if (fd != nfd) {
+ r = dup2(fd, nfd) < 0 ? -errno : nfd;
+ close_nointr_nofail(fd);
+ } else
+ r = nfd;
+
+ return r;
+}
+
+static int connect_logger_as(const ExecContext *context, ExecOutput output, const char *ident, int nfd) {
+ int fd, r;
+ union {
+ struct sockaddr sa;
+ struct sockaddr_un un;
+ } sa;
+
+ assert(context);
+ assert(output < _EXEC_OUTPUT_MAX);
+ assert(ident);
+ assert(nfd >= 0);
+
+ if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0)
+ return -errno;
+
+ zero(sa);
+ sa.sa.sa_family = AF_UNIX;
+ strncpy(sa.un.sun_path+1, LOGGER_SOCKET, sizeof(sa.un.sun_path)-1);
+
+ if (connect(fd, &sa.sa, sizeof(sa)) < 0) {
+ close_nointr_nofail(fd);
+ return -errno;
+ }
+
+ if (shutdown(fd, SHUT_RD) < 0) {
+ close_nointr_nofail(fd);
+ return -errno;
+ }
+
+ /* We speak a very simple protocol between log server
+ * and client: one line for the log destination (kmsg
+ * or syslog), followed by the priority field,
+ * followed by the process name. Since we replaced
+ * stdin/stderr we simple use stdio to write to
+ * it. Note that we use stderr, to minimize buffer
+ * flushing issues. */
+
+ dprintf(fd,
+ "%s\n"
+ "%i\n"
+ "%s\n"
+ "%i\n",
+ output == EXEC_OUTPUT_KERNEL ? "kmsg" : "syslog",
+ context->syslog_priority,
+ context->syslog_identifier ? context->syslog_identifier : ident,
+ !context->syslog_no_prefix);
+
+ if (fd != nfd) {
+ r = dup2(fd, nfd) < 0 ? -errno : nfd;
+ close_nointr_nofail(fd);
+ } else
+ r = nfd;
+
+ return r;
+}
+static int open_terminal_as(const char *path, mode_t mode, int nfd) {
+ int fd, r;
+
+ assert(path);
+ assert(nfd >= 0);
+
+ if ((fd = open_terminal(path, mode | O_NOCTTY)) < 0)
+ return fd;
+
+ if (fd != nfd) {
+ r = dup2(fd, nfd) < 0 ? -errno : nfd;
+ close_nointr_nofail(fd);
+ } else
+ r = nfd;
+
+ return r;
+}
+
+static bool is_terminal_input(ExecInput i) {
+ return
+ i == EXEC_INPUT_TTY ||
+ i == EXEC_INPUT_TTY_FORCE ||
+ i == EXEC_INPUT_TTY_FAIL;
+}
+
+static int fixup_input(const ExecContext *context, int socket_fd) {
+ assert(context);
+
+ if (socket_fd < 0 && context->std_input == EXEC_INPUT_SOCKET)
+ return EXEC_INPUT_NULL;
+
+ return context->std_input;
+}
+
+static int fixup_output(const ExecContext *context, int socket_fd) {
+ assert(context);
+
+ if (socket_fd < 0 && context->std_output == EXEC_OUTPUT_SOCKET)
+ return EXEC_OUTPUT_INHERIT;
+
+ return context->std_output;
+}
+
+static int fixup_error(const ExecContext *context, int socket_fd) {
+ assert(context);
+
+ if (socket_fd < 0 && context->std_error == EXEC_OUTPUT_SOCKET)
+ return EXEC_OUTPUT_INHERIT;
+
+ return context->std_error;
+}
+
+static int setup_input(const ExecContext *context, int socket_fd) {
+ ExecInput i;
+
+ assert(context);
+
+ i = fixup_input(context, socket_fd);
+
+ switch (i) {
+
+ case EXEC_INPUT_NULL:
+ return open_null_as(O_RDONLY, STDIN_FILENO);
+
+ case EXEC_INPUT_TTY:
+ case EXEC_INPUT_TTY_FORCE:
+ case EXEC_INPUT_TTY_FAIL: {
+ int fd, r;
+
+ if ((fd = acquire_terminal(
+ tty_path(context),
+ i == EXEC_INPUT_TTY_FAIL,
+ i == EXEC_INPUT_TTY_FORCE)) < 0)
+ return fd;
+
+ if (fd != STDIN_FILENO) {
+ r = dup2(fd, STDIN_FILENO) < 0 ? -errno : STDIN_FILENO;
+ close_nointr_nofail(fd);
+ } else
+ r = STDIN_FILENO;
+
+ return r;
+ }
+
+ case EXEC_INPUT_SOCKET:
+ return dup2(socket_fd, STDIN_FILENO) < 0 ? -errno : STDIN_FILENO;
+
+ default:
+ assert_not_reached("Unknown input type");
+ }
+}
+
+static int setup_output(const ExecContext *context, int socket_fd, const char *ident) {
+ ExecOutput o;
+ ExecInput i;
+
+ assert(context);
+ assert(ident);
+
+ i = fixup_input(context, socket_fd);
+ o = fixup_output(context, socket_fd);
+
+ /* This expects the input is already set up */
+
+ switch (o) {
+
+ case EXEC_OUTPUT_INHERIT:
+
+ /* If the input is connected to a terminal, inherit that... */
+ if (is_terminal_input(i) || i == EXEC_INPUT_SOCKET)
+ return dup2(STDIN_FILENO, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
+
+ return STDIN_FILENO;
+
+ case EXEC_OUTPUT_NULL:
+ return open_null_as(O_WRONLY, STDOUT_FILENO);
+
+ case EXEC_OUTPUT_TTY:
+ if (is_terminal_input(i))
+ return dup2(STDIN_FILENO, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
+
+ /* We don't reset the terminal if this is just about output */
+ return open_terminal_as(tty_path(context), O_WRONLY, STDOUT_FILENO);
+
+ case EXEC_OUTPUT_SYSLOG:
+ case EXEC_OUTPUT_KERNEL:
+ return connect_logger_as(context, o, ident, STDOUT_FILENO);
+
+ case EXEC_OUTPUT_SOCKET:
+ assert(socket_fd >= 0);
+ return dup2(socket_fd, STDOUT_FILENO) < 0 ? -errno : STDOUT_FILENO;
+
+ default:
+ assert_not_reached("Unknown output type");
+ }
+}
+
+static int setup_error(const ExecContext *context, int socket_fd, const char *ident) {
+ ExecOutput o, e;
+ ExecInput i;
+
+ assert(context);
+ assert(ident);
+
+ i = fixup_input(context, socket_fd);
+ o = fixup_output(context, socket_fd);
+ e = fixup_error(context, socket_fd);
+
+ /* This expects the input and output are already set up */
+
+ /* Don't change the stderr file descriptor if we inherit all
+ * the way and are not on a tty */
+ if (e == EXEC_OUTPUT_INHERIT &&
+ o == EXEC_OUTPUT_INHERIT &&
+ !is_terminal_input(i))
+ return STDERR_FILENO;
+
+ /* Duplicate form stdout if possible */
+ if (e == o || e == EXEC_OUTPUT_INHERIT)
+ return dup2(STDOUT_FILENO, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
+
+ switch (e) {
+
+ case EXEC_OUTPUT_NULL:
+ return open_null_as(O_WRONLY, STDERR_FILENO);
+
+ case EXEC_OUTPUT_TTY:
+ if (is_terminal_input(i))
+ return dup2(STDIN_FILENO, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
+
+ /* We don't reset the terminal if this is just about output */
+ return open_terminal_as(tty_path(context), O_WRONLY, STDERR_FILENO);
+
+ case EXEC_OUTPUT_SYSLOG:
+ case EXEC_OUTPUT_KERNEL:
+ return connect_logger_as(context, e, ident, STDERR_FILENO);
+
+ case EXEC_OUTPUT_SOCKET:
+ assert(socket_fd >= 0);
+ return dup2(socket_fd, STDERR_FILENO) < 0 ? -errno : STDERR_FILENO;
+
+ default:
+ assert_not_reached("Unknown error type");
+ }
+}
+
+static int chown_terminal(int fd, uid_t uid) {
+ struct stat st;
+
+ assert(fd >= 0);
+
+ /* This might fail. What matters are the results. */
+ (void) fchown(fd, uid, -1);
+ (void) fchmod(fd, TTY_MODE);
+
+ if (fstat(fd, &st) < 0)
+ return -errno;
+
+ if (st.st_uid != uid || (st.st_mode & 0777) != TTY_MODE)
+ return -EPERM;
+
+ return 0;
+}
+
+static int setup_confirm_stdio(const ExecContext *context,
+ int *_saved_stdin,
+ int *_saved_stdout) {
+ int fd = -1, saved_stdin, saved_stdout = -1, r;
+
+ assert(context);
+ assert(_saved_stdin);
+ assert(_saved_stdout);
+
+ /* This returns positive EXIT_xxx return values instead of
+ * negative errno style values! */
+
+ if ((saved_stdin = fcntl(STDIN_FILENO, F_DUPFD, 3)) < 0)
+ return EXIT_STDIN;
+
+ if ((saved_stdout = fcntl(STDOUT_FILENO, F_DUPFD, 3)) < 0) {
+ r = EXIT_STDOUT;
+ goto fail;
+ }
+
+ if ((fd = acquire_terminal(
+ tty_path(context),
+ context->std_input == EXEC_INPUT_TTY_FAIL,
+ context->std_input == EXEC_INPUT_TTY_FORCE)) < 0) {
+ r = EXIT_STDIN;
+ goto fail;
+ }
+
+ if (chown_terminal(fd, getuid()) < 0) {
+ r = EXIT_STDIN;
+ goto fail;
+ }
+
+ if (dup2(fd, STDIN_FILENO) < 0) {
+ r = EXIT_STDIN;
+ goto fail;
+ }
+
+ if (dup2(fd, STDOUT_FILENO) < 0) {
+ r = EXIT_STDOUT;
+ goto fail;
+ }
+
+ if (fd >= 2)
+ close_nointr_nofail(fd);
+
+ *_saved_stdin = saved_stdin;
+ *_saved_stdout = saved_stdout;
+
+ return 0;
+
+fail:
+ if (saved_stdout >= 0)
+ close_nointr_nofail(saved_stdout);
+
+ if (saved_stdin >= 0)
+ close_nointr_nofail(saved_stdin);
+
+ if (fd >= 0)
+ close_nointr_nofail(fd);
+
+ return r;
+}
+
+static int restore_confirm_stdio(const ExecContext *context,
+ int *saved_stdin,
+ int *saved_stdout,
+ bool *keep_stdin,
+ bool *keep_stdout) {
+
+ assert(context);
+ assert(saved_stdin);
+ assert(*saved_stdin >= 0);
+ assert(saved_stdout);
+ assert(*saved_stdout >= 0);
+
+ /* This returns positive EXIT_xxx return values instead of
+ * negative errno style values! */
+
+ if (is_terminal_input(context->std_input)) {
+
+ /* The service wants terminal input. */
+
+ *keep_stdin = true;
+ *keep_stdout =
+ context->std_output == EXEC_OUTPUT_INHERIT ||
+ context->std_output == EXEC_OUTPUT_TTY;
+
+ } else {
+ /* If the service doesn't want a controlling terminal,
+ * then we need to get rid entirely of what we have
+ * already. */
+
+ if (release_terminal() < 0)
+ return EXIT_STDIN;
+
+ if (dup2(*saved_stdin, STDIN_FILENO) < 0)
+ return EXIT_STDIN;
+
+ if (dup2(*saved_stdout, STDOUT_FILENO) < 0)
+ return EXIT_STDOUT;
+
+ *keep_stdout = *keep_stdin = false;
+ }
+
+ return 0;
+}
+
+static int get_group_creds(const char *groupname, gid_t *gid) {
+ struct group *g;
+ unsigned long lu;
+
+ assert(groupname);
+ assert(gid);
+
+ /* We enforce some special rules for gid=0: in order to avoid
+ * NSS lookups for root we hardcode its data. */
+
+ if (streq(groupname, "root") || streq(groupname, "0")) {
+ *gid = 0;
+ return 0;
+ }
+
+ if (safe_atolu(groupname, &lu) >= 0) {
+ errno = 0;
+ g = getgrgid((gid_t) lu);
+ } else {
+ errno = 0;
+ g = getgrnam(groupname);
+ }
+
+ if (!g)
+ return errno != 0 ? -errno : -ESRCH;
+
+ *gid = g->gr_gid;
+ return 0;
+}
+
+static int get_user_creds(const char **username, uid_t *uid, gid_t *gid, const char **home) {
+ struct passwd *p;
+ unsigned long lu;
+
+ assert(username);
+ assert(*username);
+ assert(uid);
+ assert(gid);
+ assert(home);
+
+ /* We enforce some special rules for uid=0: in order to avoid
+ * NSS lookups for root we hardcode its data. */
+
+ if (streq(*username, "root") || streq(*username, "0")) {
+ *username = "root";
+ *uid = 0;
+ *gid = 0;
+ *home = "/root";
+ return 0;
+ }
+
+ if (safe_atolu(*username, &lu) >= 0) {
+ errno = 0;
+ p = getpwuid((uid_t) lu);
+
+ /* If there are multiple users with the same id, make
+ * sure to leave $USER to the configured value instead
+ * of the first occurence in the database. However if
+ * the uid was configured by a numeric uid, then let's
+ * pick the real username from /etc/passwd. */
+ if (*username && p)
+ *username = p->pw_name;
+ } else {
+ errno = 0;
+ p = getpwnam(*username);
+ }
+
+ if (!p)
+ return errno != 0 ? -errno : -ESRCH;
+
+ *uid = p->pw_uid;
+ *gid = p->pw_gid;
+ *home = p->pw_dir;
+ return 0;
+}
+
+static int enforce_groups(const ExecContext *context, const char *username, gid_t gid) {
+ bool keep_groups = false;
+ int r;
+
+ assert(context);
+
+ /* Lookup and ser GID and supplementary group list. Here too
+ * we avoid NSS lookups for gid=0. */
+
+ if (context->group || username) {
+
+ if (context->group)
+ if ((r = get_group_creds(context->group, &gid)) < 0)
+ return r;
+
+ /* First step, initialize groups from /etc/groups */
+ if (username && gid != 0) {
+ if (initgroups(username, gid) < 0)
+ return -errno;
+
+ keep_groups = true;
+ }
+
+ /* Second step, set our gids */
+ if (setresgid(gid, gid, gid) < 0)
+ return -errno;
+ }
+
+ if (context->supplementary_groups) {
+ int ngroups_max, k;
+ gid_t *gids;
+ char **i;
+
+ /* Final step, initialize any manually set supplementary groups */
+ ngroups_max = (int) sysconf(_SC_NGROUPS_MAX);
+
+ if (!(gids = new(gid_t, ngroups_max)))
+ return -ENOMEM;
+
+ if (keep_groups) {
+ if ((k = getgroups(ngroups_max, gids)) < 0) {
+ free(gids);
+ return -errno;
+ }
+ } else
+ k = 0;
+
+ STRV_FOREACH(i, context->supplementary_groups) {
+
+ if (k >= ngroups_max) {
+ free(gids);
+ return -E2BIG;
+ }
+
+ if ((r = get_group_creds(*i, gids+k)) < 0) {
+ free(gids);
+ return r;
+ }
+
+ k++;
+ }
+
+ if (setgroups(k, gids) < 0) {
+ free(gids);
+ return -errno;
+ }
+
+ free(gids);
+ }
+
+ return 0;
+}
+
+static int enforce_user(const ExecContext *context, uid_t uid) {
+ int r;
+ assert(context);
+
+ /* Sets (but doesn't lookup) the uid and make sure we keep the
+ * capabilities while doing so. */
+
+ if (context->capabilities) {
+ cap_t d;
+ static const cap_value_t bits[] = {
+ CAP_SETUID, /* Necessary so that we can run setresuid() below */
+ CAP_SETPCAP /* Necessary so that we can set PR_SET_SECUREBITS later on */
+ };
+
+ /* First step: If we need to keep capabilities but
+ * drop privileges we need to make sure we keep our
+ * caps, whiel we drop priviliges. */
+ if (uid != 0) {
+ int sb = context->secure_bits|SECURE_KEEP_CAPS;
+
+ if (prctl(PR_GET_SECUREBITS) != sb)
+ if (prctl(PR_SET_SECUREBITS, sb) < 0)
+ return -errno;
+ }
+
+ /* Second step: set the capabilites. This will reduce
+ * the capabilities to the minimum we need. */
+
+ if (!(d = cap_dup(context->capabilities)))
+ return -errno;
+
+ if (cap_set_flag(d, CAP_EFFECTIVE, ELEMENTSOF(bits), bits, CAP_SET) < 0 ||
+ cap_set_flag(d, CAP_PERMITTED, ELEMENTSOF(bits), bits, CAP_SET) < 0) {
+ r = -errno;
+ cap_free(d);
+ return r;
+ }
+
+ if (cap_set_proc(d) < 0) {
+ r = -errno;
+ cap_free(d);
+ return r;
+ }
+
+ cap_free(d);
+ }
+
+ /* Third step: actually set the uids */
+ if (setresuid(uid, uid, uid) < 0)
+ return -errno;
+
+ /* At this point we should have all necessary capabilities but
+ are otherwise a normal user. However, the caps might got
+ corrupted due to the setresuid() so we need clean them up
+ later. This is done outside of this call. */
+
+ return 0;
+}
+
+int exec_spawn(ExecCommand *command,
+ char **argv,
+ const ExecContext *context,
+ int fds[], unsigned n_fds,
+ char **environment,
+ bool apply_permissions,
+ bool apply_chroot,
+ bool confirm_spawn,
+ CGroupBonding *cgroup_bondings,
+ pid_t *ret) {
+
+ pid_t pid;
+ int r;
+ char *line;
+ int socket_fd;
+
+ assert(command);
+ assert(context);
+ assert(ret);
+ assert(fds || n_fds <= 0);
+
+ if (context->std_input == EXEC_INPUT_SOCKET ||
+ context->std_output == EXEC_OUTPUT_SOCKET ||
+ context->std_error == EXEC_OUTPUT_SOCKET) {
+
+ if (n_fds != 1)
+ return -EINVAL;
+
+ socket_fd = fds[0];
+
+ fds = NULL;
+ n_fds = 0;
+ } else
+ socket_fd = -1;
+
+ if (!argv)
+ argv = command->argv;
+
+ if (!(line = exec_command_line(argv)))
+ return -ENOMEM;
+
+ log_debug("About to execute: %s", line);
+ free(line);
+
+ if (cgroup_bondings)
+ if ((r = cgroup_bonding_realize_list(cgroup_bondings)))
+ return r;
+
+ if ((pid = fork()) < 0)
+ return -errno;
+
+ if (pid == 0) {
+ int i;
+ sigset_t ss;
+ const char *username = NULL, *home = NULL;
+ uid_t uid = (uid_t) -1;
+ gid_t gid = (gid_t) -1;
+ char **our_env = NULL, **final_env = NULL;
+ unsigned n_env = 0;
+ int saved_stdout = -1, saved_stdin = -1;
+ bool keep_stdout = false, keep_stdin = false;
+
+ /* child */
+
+ reset_all_signal_handlers();
+
+ if (sigemptyset(&ss) < 0 ||
+ sigprocmask(SIG_SETMASK, &ss, NULL) < 0) {
+ r = EXIT_SIGNAL_MASK;
+ goto fail;
+ }
+
+ if (!context->no_setsid)
+ if (setsid() < 0) {
+ r = EXIT_SETSID;
+ goto fail;
+ }
+
+ if (confirm_spawn) {
+ char response;
+
+ /* Set up terminal for the question */
+ if ((r = setup_confirm_stdio(context,
+ &saved_stdin, &saved_stdout)))
+ goto fail;
+
+ /* Now ask the question. */
+ if (!(line = exec_command_line(argv))) {
+ r = EXIT_MEMORY;
+ goto fail;
+ }
+
+ r = ask(&response, "yns", "Execute %s? [Yes, No, Skip] ", line);
+ free(line);
+
+ if (r < 0 || response == 'n') {
+ r = EXIT_CONFIRM;
+ goto fail;
+ } else if (response == 's') {
+ r = 0;
+ goto fail;
+ }
+
+ /* Release terminal for the question */
+ if ((r = restore_confirm_stdio(context,
+ &saved_stdin, &saved_stdout,
+ &keep_stdin, &keep_stdout)))
+ goto fail;
+ }
+
+ if (!keep_stdin)
+ if (setup_input(context, socket_fd) < 0) {
+ r = EXIT_STDIN;
+ goto fail;
+ }
+
+ if (!keep_stdout)
+ if (setup_output(context, socket_fd, file_name_from_path(command->path)) < 0) {
+ r = EXIT_STDOUT;
+ goto fail;
+ }
+
+ if (setup_error(context, socket_fd, file_name_from_path(command->path)) < 0) {
+ r = EXIT_STDERR;
+ goto fail;
+ }
+
+ if (cgroup_bondings)
+ if ((r = cgroup_bonding_install_list(cgroup_bondings, 0)) < 0) {
+ r = EXIT_CGROUP;
+ goto fail;
+ }
+
+ if (context->oom_adjust_set) {
+ char t[16];
+
+ snprintf(t, sizeof(t), "%i", context->oom_adjust);
+ char_array_0(t);
+
+ if (write_one_line_file("/proc/self/oom_adj", t) < 0) {
+ r = EXIT_OOM_ADJUST;
+ goto fail;
+ }
+ }
+
+ if (context->nice_set)
+ if (setpriority(PRIO_PROCESS, 0, context->nice) < 0) {
+ r = EXIT_NICE;
+ goto fail;
+ }
+
+ if (context->cpu_sched_set) {
+ struct sched_param param;
+
+ zero(param);
+ param.sched_priority = context->cpu_sched_priority;
+
+ if (sched_setscheduler(0, context->cpu_sched_policy |
+ (context->cpu_sched_reset_on_fork ? SCHED_RESET_ON_FORK : 0), &param) < 0) {
+ r = EXIT_SETSCHEDULER;
+ goto fail;
+ }
+ }
+
+ if (context->cpu_affinity_set)
+ if (sched_setaffinity(0, sizeof(context->cpu_affinity), &context->cpu_affinity) < 0) {
+ r = EXIT_CPUAFFINITY;
+ goto fail;
+ }
+
+ if (context->ioprio_set)
+ if (ioprio_set(IOPRIO_WHO_PROCESS, 0, context->ioprio) < 0) {
+ r = EXIT_IOPRIO;
+ goto fail;
+ }
+
+ if (context->timer_slack_ns_set)
+ if (prctl(PR_SET_TIMERSLACK, context->timer_slack_ns_set) < 0) {
+ r = EXIT_TIMERSLACK;
+ goto fail;
+ }
+
+ if (strv_length(context->read_write_dirs) > 0 ||
+ strv_length(context->read_only_dirs) > 0 ||
+ strv_length(context->inaccessible_dirs) > 0 ||
+ context->mount_flags != MS_SHARED ||
+ context->private_tmp)
+ if ((r = setup_namespace(
+ context->read_write_dirs,
+ context->read_only_dirs,
+ context->inaccessible_dirs,
+ context->private_tmp,
+ context->mount_flags)) < 0)
+ goto fail;
+
+ if (context->user) {
+ username = context->user;
+ if (get_user_creds(&username, &uid, &gid, &home) < 0) {
+ r = EXIT_USER;
+ goto fail;
+ }
+
+ if (is_terminal_input(context->std_input))
+ if (chown_terminal(STDIN_FILENO, uid) < 0) {
+ r = EXIT_STDIN;
+ goto fail;
+ }
+ }
+
+ if (apply_permissions)
+ if (enforce_groups(context, username, uid) < 0) {
+ r = EXIT_GROUP;
+ goto fail;
+ }
+
+ umask(context->umask);
+
+ if (apply_chroot) {
+ if (context->root_directory)
+ if (chroot(context->root_directory) < 0) {
+ r = EXIT_CHROOT;
+ goto fail;
+ }
+
+ if (chdir(context->working_directory ? context->working_directory : "/") < 0) {
+ r = EXIT_CHDIR;
+ goto fail;
+ }
+ } else {
+
+ char *d;
+
+ if (asprintf(&d, "%s/%s",
+ context->root_directory ? context->root_directory : "",
+ context->working_directory ? context->working_directory : "") < 0) {
+ r = EXIT_MEMORY;
+ goto fail;
+ }
+
+ if (chdir(d) < 0) {
+ free(d);
+ r = EXIT_CHDIR;
+ goto fail;
+ }
+
+ free(d);
+ }
+
+ if (close_all_fds(fds, n_fds) < 0 ||
+ shift_fds(fds, n_fds) < 0 ||
+ flags_fds(fds, n_fds, context->non_blocking) < 0) {
+ r = EXIT_FDS;
+ goto fail;
+ }
+
+ if (apply_permissions) {
+
+ for (i = 0; i < RLIMIT_NLIMITS; i++) {
+ if (!context->rlimit[i])
+ continue;
+
+ if (setrlimit(i, context->rlimit[i]) < 0) {
+ r = EXIT_LIMITS;
+ goto fail;
+ }
+ }
+
+ if (context->user)
+ if (enforce_user(context, uid) < 0) {
+ r = EXIT_USER;
+ goto fail;
+ }
+
+ /* PR_GET_SECUREBITS is not priviliged, while
+ * PR_SET_SECUREBITS is. So to suppress
+ * potential EPERMs we'll try not to call
+ * PR_SET_SECUREBITS unless necessary. */
+ if (prctl(PR_GET_SECUREBITS) != context->secure_bits)
+ if (prctl(PR_SET_SECUREBITS, context->secure_bits) < 0) {
+ r = EXIT_SECUREBITS;
+ goto fail;
+ }
+
+ if (context->capabilities)
+ if (cap_set_proc(context->capabilities) < 0) {
+ r = EXIT_CAPABILITIES;
+ goto fail;
+ }
+ }
+
+ if (!(our_env = new0(char*, 6))) {
+ r = EXIT_MEMORY;
+ goto fail;
+ }
+
+ if (n_fds > 0)
+ if (asprintf(our_env + n_env++, "LISTEN_PID=%llu", (unsigned long long) getpid()) < 0 ||
+ asprintf(our_env + n_env++, "LISTEN_FDS=%u", n_fds) < 0) {
+ r = EXIT_MEMORY;
+ goto fail;
+ }
+
+ if (home)
+ if (asprintf(our_env + n_env++, "HOME=%s", home) < 0) {
+ r = EXIT_MEMORY;
+ goto fail;
+ }
+
+ if (username)
+ if (asprintf(our_env + n_env++, "LOGNAME=%s", username) < 0 ||
+ asprintf(our_env + n_env++, "USER=%s", username) < 0) {
+ r = EXIT_MEMORY;
+ goto fail;
+ }
+
+ assert(n_env <= 6);
+
+ if (!(final_env = strv_env_merge(environment, our_env, context->environment, NULL))) {
+ r = EXIT_MEMORY;
+ goto fail;
+ }
+
+ execve(command->path, argv, final_env);
+ r = EXIT_EXEC;
+
+ fail:
+ strv_free(our_env);
+ strv_free(final_env);
+
+ if (saved_stdin >= 0)
+ close_nointr_nofail(saved_stdin);
+
+ if (saved_stdout >= 0)
+ close_nointr_nofail(saved_stdout);
+
+ _exit(r);
+ }
+
+ /* We add the new process to the cgroup both in the child (so
+ * that we can be sure that no user code is ever executed
+ * outside of the cgroup) and in the parent (so that we can be
+ * sure that when we kill the cgroup the process will be
+ * killed too). */
+ if (cgroup_bondings)
+ cgroup_bonding_install_list(cgroup_bondings, pid);
+
+ log_debug("Forked %s as %llu", command->path, (unsigned long long) pid);
+
+ command->exec_status.pid = pid;
+ command->exec_status.start_timestamp = now(CLOCK_REALTIME);
+
+ *ret = pid;
+ return 0;
+}
+
+void exec_context_init(ExecContext *c) {
+ assert(c);
+
+ c->umask = 0002;
+ c->ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 0);
+ c->cpu_sched_policy = SCHED_OTHER;
+ c->syslog_priority = LOG_DAEMON|LOG_INFO;
+ c->mount_flags = MS_SHARED;
+}
+
+void exec_context_done(ExecContext *c) {
+ unsigned l;
+
+ assert(c);
+
+ strv_free(c->environment);
+ c->environment = NULL;
+
+ for (l = 0; l < ELEMENTSOF(c->rlimit); l++) {
+ free(c->rlimit[l]);
+ c->rlimit[l] = NULL;
+ }
+
+ free(c->working_directory);
+ c->working_directory = NULL;
+ free(c->root_directory);
+ c->root_directory = NULL;
+
+ free(c->tty_path);
+ c->tty_path = NULL;
+
+ free(c->syslog_identifier);
+ c->syslog_identifier = NULL;
+
+ free(c->user);
+ c->user = NULL;
+
+ free(c->group);
+ c->group = NULL;
+
+ strv_free(c->supplementary_groups);
+ c->supplementary_groups = NULL;
+
+ if (c->capabilities) {
+ cap_free(c->capabilities);
+ c->capabilities = NULL;
+ }
+
+ strv_free(c->read_only_dirs);
+ c->read_only_dirs = NULL;
+
+ strv_free(c->read_write_dirs);
+ c->read_write_dirs = NULL;
+
+ strv_free(c->inaccessible_dirs);
+ c->inaccessible_dirs = NULL;
+}
+
+void exec_command_done(ExecCommand *c) {
+ assert(c);
+
+ free(c->path);
+ c->path = NULL;
+
+ strv_free(c->argv);
+ c->argv = NULL;
+}
+
+void exec_command_done_array(ExecCommand *c, unsigned n) {
+ unsigned i;
+
+ for (i = 0; i < n; i++)
+ exec_command_done(c+i);
+}
+
+void exec_command_free_list(ExecCommand *c) {
+ ExecCommand *i;
+
+ while ((i = c)) {
+ LIST_REMOVE(ExecCommand, command, c, i);
+ exec_command_done(i);
+ free(i);
+ }
+}
+
+void exec_command_free_array(ExecCommand **c, unsigned n) {
+ unsigned i;
+
+ for (i = 0; i < n; i++) {
+ exec_command_free_list(c[i]);
+ c[i] = NULL;
+ }
+}
+
+static void strv_fprintf(FILE *f, char **l) {
+ char **g;
+
+ assert(f);
+
+ STRV_FOREACH(g, l)
+ fprintf(f, " %s", *g);
+}
+
+void exec_context_dump(ExecContext *c, FILE* f, const char *prefix) {
+ char ** e;
+ unsigned i;
+
+ assert(c);
+ assert(f);
+
+ if (!prefix)
+ prefix = "";
+
+ fprintf(f,
+ "%sUMask: %04o\n"
+ "%sWorkingDirectory: %s\n"
+ "%sRootDirectory: %s\n"
+ "%sNonBlocking: %s\n"
+ "%sPrivateTmp: %s\n",
+ prefix, c->umask,
+ prefix, c->working_directory ? c->working_directory : "/",
+ prefix, c->root_directory ? c->root_directory : "/",
+ prefix, yes_no(c->non_blocking),
+ prefix, yes_no(c->private_tmp));
+
+ if (c->environment)
+ for (e = c->environment; *e; e++)
+ fprintf(f, "%sEnvironment: %s\n", prefix, *e);
+
+ if (c->nice_set)
+ fprintf(f,
+ "%sNice: %i\n",
+ prefix, c->nice);
+
+ if (c->oom_adjust_set)
+ fprintf(f,
+ "%sOOMAdjust: %i\n",
+ prefix, c->oom_adjust);
+
+ for (i = 0; i < RLIM_NLIMITS; i++)
+ if (c->rlimit[i])
+ fprintf(f, "%s%s: %llu\n", prefix, rlimit_to_string(i), (unsigned long long) c->rlimit[i]->rlim_max);
+
+ if (c->ioprio_set)
+ fprintf(f,
+ "%sIOSchedulingClass: %s\n"
+ "%sIOPriority: %i\n",
+ prefix, ioprio_class_to_string(IOPRIO_PRIO_CLASS(c->ioprio)),
+ prefix, (int) IOPRIO_PRIO_DATA(c->ioprio));
+
+ if (c->cpu_sched_set)
+ fprintf(f,
+ "%sCPUSchedulingPolicy: %s\n"
+ "%sCPUSchedulingPriority: %i\n"
+ "%sCPUSchedulingResetOnFork: %s\n",
+ prefix, sched_policy_to_string(c->cpu_sched_policy),
+ prefix, c->cpu_sched_priority,
+ prefix, yes_no(c->cpu_sched_reset_on_fork));
+
+ if (c->cpu_affinity_set) {
+ fprintf(f, "%sCPUAffinity:", prefix);
+ for (i = 0; i < CPU_SETSIZE; i++)
+ if (CPU_ISSET(i, &c->cpu_affinity))
+ fprintf(f, " %i", i);
+ fputs("\n", f);
+ }
+
+ if (c->timer_slack_ns_set)
+ fprintf(f, "%sTimerSlackNS: %lu\n", prefix, c->timer_slack_ns);
+
+ fprintf(f,
+ "%sStandardInput: %s\n"
+ "%sStandardOutput: %s\n"
+ "%sStandardError: %s\n",
+ prefix, exec_input_to_string(c->std_input),
+ prefix, exec_output_to_string(c->std_output),
+ prefix, exec_output_to_string(c->std_error));
+
+ if (c->tty_path)
+ fprintf(f,
+ "%sTTYPath: %s\n",
+ prefix, c->tty_path);
+
+ if (c->std_output == EXEC_OUTPUT_SYSLOG || c->std_output == EXEC_OUTPUT_KERNEL ||
+ c->std_error == EXEC_OUTPUT_SYSLOG || c->std_error == EXEC_OUTPUT_KERNEL)
+ fprintf(f,
+ "%sSyslogFacility: %s\n"
+ "%sSyslogLevel: %s\n",
+ prefix, log_facility_to_string(LOG_FAC(c->syslog_priority)),
+ prefix, log_level_to_string(LOG_PRI(c->syslog_priority)));
+
+ if (c->capabilities) {
+ char *t;
+ if ((t = cap_to_text(c->capabilities, NULL))) {
+ fprintf(f, "%sCapabilities: %s\n",
+ prefix, t);
+ cap_free(t);
+ }
+ }
+
+ if (c->secure_bits)
+ fprintf(f, "%sSecure Bits:%s%s%s%s%s%s\n",
+ prefix,
+ (c->secure_bits & SECURE_KEEP_CAPS) ? " keep-caps" : "",
+ (c->secure_bits & SECURE_KEEP_CAPS_LOCKED) ? " keep-caps-locked" : "",
+ (c->secure_bits & SECURE_NO_SETUID_FIXUP) ? " no-setuid-fixup" : "",
+ (c->secure_bits & SECURE_NO_SETUID_FIXUP_LOCKED) ? " no-setuid-fixup-locked" : "",
+ (c->secure_bits & SECURE_NOROOT) ? " noroot" : "",
+ (c->secure_bits & SECURE_NOROOT_LOCKED) ? "noroot-locked" : "");
+
+ if (c->capability_bounding_set_drop) {
+ fprintf(f, "%sCapabilityBoundingSetDrop:", prefix);
+
+ for (i = 0; i <= CAP_LAST_CAP; i++)
+ if (c->capability_bounding_set_drop & (1 << i)) {
+ char *t;
+
+ if ((t = cap_to_name(i))) {
+ fprintf(f, " %s", t);
+ free(t);
+ }
+ }
+
+ fputs("\n", f);
+ }
+
+ if (c->user)
+ fprintf(f, "%sUser: %s", prefix, c->user);
+ if (c->group)
+ fprintf(f, "%sGroup: %s", prefix, c->group);
+
+ if (strv_length(c->supplementary_groups) > 0) {
+ fprintf(f, "%sSupplementaryGroups:", prefix);
+ strv_fprintf(f, c->supplementary_groups);
+ fputs("\n", f);
+ }
+
+ if (strv_length(c->read_write_dirs) > 0) {
+ fprintf(f, "%sReadWriteDirs:", prefix);
+ strv_fprintf(f, c->read_write_dirs);
+ fputs("\n", f);
+ }
+
+ if (strv_length(c->read_only_dirs) > 0) {
+ fprintf(f, "%sReadOnlyDirs:", prefix);
+ strv_fprintf(f, c->read_only_dirs);
+ fputs("\n", f);
+ }
+
+ if (strv_length(c->inaccessible_dirs) > 0) {
+ fprintf(f, "%sInaccessibleDirs:", prefix);
+ strv_fprintf(f, c->inaccessible_dirs);
+ fputs("\n", f);
+ }
+}
+
+void exec_status_fill(ExecStatus *s, pid_t pid, int code, int status) {
+ assert(s);
+
+ s->pid = pid;
+ s->exit_timestamp = now(CLOCK_REALTIME);
+
+ s->code = code;
+ s->status = status;
+}
+
+void exec_status_dump(ExecStatus *s, FILE *f, const char *prefix) {
+ char buf[FORMAT_TIMESTAMP_MAX];
+
+ assert(s);
+ assert(f);
+
+ if (!prefix)
+ prefix = "";
+
+ if (s->pid <= 0)
+ return;
+
+ fprintf(f,
+ "%sPID: %llu\n",
+ prefix, (unsigned long long) s->pid);
+
+ if (s->start_timestamp > 0)
+ fprintf(f,
+ "%sStart Timestamp: %s\n",
+ prefix, format_timestamp(buf, sizeof(buf), s->start_timestamp));
+
+ if (s->exit_timestamp > 0)
+ fprintf(f,
+ "%sExit Timestamp: %s\n"
+ "%sExit Code: %s\n"
+ "%sExit Status: %i\n",
+ prefix, format_timestamp(buf, sizeof(buf), s->exit_timestamp),
+ prefix, sigchld_code_to_string(s->code),
+ prefix, s->status);
+}
+
+char *exec_command_line(char **argv) {
+ size_t k;
+ char *n, *p, **a;
+ bool first = true;
+
+ assert(argv);
+
+ k = 1;
+ STRV_FOREACH(a, argv)
+ k += strlen(*a)+3;
+
+ if (!(n = new(char, k)))
+ return NULL;
+
+ p = n;
+ STRV_FOREACH(a, argv) {
+
+ if (!first)
+ *(p++) = ' ';
+ else
+ first = false;
+
+ if (strpbrk(*a, WHITESPACE)) {
+ *(p++) = '\'';
+ p = stpcpy(p, *a);
+ *(p++) = '\'';
+ } else
+ p = stpcpy(p, *a);
+
+ }
+
+ *p = 0;
+
+ /* FIXME: this doesn't really handle arguments that have
+ * spaces and ticks in them */
+
+ return n;
+}
+
+void exec_command_dump(ExecCommand *c, FILE *f, const char *prefix) {
+ char *p2;
+ const char *prefix2;
+
+ char *cmd;
+
+ assert(c);
+ assert(f);
+
+ if (!prefix)
+ prefix = "";
+ p2 = strappend(prefix, "\t");
+ prefix2 = p2 ? p2 : prefix;
+
+ cmd = exec_command_line(c->argv);
+
+ fprintf(f,
+ "%sCommand Line: %s\n",
+ prefix, cmd ? cmd : strerror(ENOMEM));
+
+ free(cmd);
+
+ exec_status_dump(&c->exec_status, f, prefix2);
+
+ free(p2);
+}
+
+void exec_command_dump_list(ExecCommand *c, FILE *f, const char *prefix) {
+ assert(f);
+
+ if (!prefix)
+ prefix = "";
+
+ LIST_FOREACH(command, c, c)
+ exec_command_dump(c, f, prefix);
+}
+
+void exec_command_append_list(ExecCommand **l, ExecCommand *e) {
+ ExecCommand *end;
+
+ assert(l);
+ assert(e);
+
+ if (*l) {
+ /* It's kinda important that we keep the order here */
+ LIST_FIND_TAIL(ExecCommand, command, *l, end);
+ LIST_INSERT_AFTER(ExecCommand, command, *l, end, e);
+ } else
+ *l = e;
+}
+
+int exec_command_set(ExecCommand *c, const char *path, ...) {
+ va_list ap;
+ char **l, *p;
+
+ assert(c);
+ assert(path);
+
+ va_start(ap, path);
+ l = strv_new_ap(path, ap);
+ va_end(ap);
+
+ if (!l)
+ return -ENOMEM;
+
+ if (!(p = strdup(path))) {
+ strv_free(l);
+ return -ENOMEM;
+ }
+
+ free(c->path);
+ c->path = p;
+
+ strv_free(c->argv);
+ c->argv = l;
+
+ return 0;
+}
+
+const char* exit_status_to_string(ExitStatus status) {
+
+ /* We cast to int here, so that -Wenum doesn't complain that
+ * EXIT_SUCCESS/EXIT_FAILURE aren't in the enum */
+
+ switch ((int) status) {
+
+ case EXIT_SUCCESS:
+ return "SUCCESS";
+
+ case EXIT_FAILURE:
+ return "FAILURE";
+
+ case EXIT_INVALIDARGUMENT:
+ return "INVALIDARGUMENT";
+
+ case EXIT_NOTIMPLEMENTED:
+ return "NOTIMPLEMENTED";
+
+ case EXIT_NOPERMISSION:
+ return "NOPERMISSION";
+
+ case EXIT_NOTINSTALLED:
+ return "NOTINSSTALLED";
+
+ case EXIT_NOTCONFIGURED:
+ return "NOTCONFIGURED";
+
+ case EXIT_NOTRUNNING:
+ return "NOTRUNNING";
+
+ case EXIT_CHDIR:
+ return "CHDIR";
+
+ case EXIT_NICE:
+ return "NICE";
+
+ case EXIT_FDS:
+ return "FDS";
+
+ case EXIT_EXEC:
+ return "EXEC";
+
+ case EXIT_MEMORY:
+ return "MEMORY";
+
+ case EXIT_LIMITS:
+ return "LIMITS";
+
+ case EXIT_OOM_ADJUST:
+ return "OOM_ADJUST";
+
+ case EXIT_SIGNAL_MASK:
+ return "SIGNAL_MASK";
+
+ case EXIT_STDIN:
+ return "STDIN";
+
+ case EXIT_STDOUT:
+ return "STDOUT";
+
+ case EXIT_CHROOT:
+ return "CHROOT";
+
+ case EXIT_IOPRIO:
+ return "IOPRIO";
+
+ case EXIT_TIMERSLACK:
+ return "TIMERSLACK";
+
+ case EXIT_SECUREBITS:
+ return "SECUREBITS";
+
+ case EXIT_SETSCHEDULER:
+ return "SETSCHEDULER";
+
+ case EXIT_CPUAFFINITY:
+ return "CPUAFFINITY";
+
+ case EXIT_GROUP:
+ return "GROUP";
+
+ case EXIT_USER:
+ return "USER";
+
+ case EXIT_CAPABILITIES:
+ return "CAPABILITIES";
+
+ case EXIT_CGROUP:
+ return "CGROUP";
+
+ case EXIT_SETSID:
+ return "SETSID";
+
+ case EXIT_CONFIRM:
+ return "CONFIRM";
+
+ case EXIT_STDERR:
+ return "STDERR";
+
+ default:
+ return NULL;
+ }
+}
+
+static const char* const exec_input_table[_EXEC_INPUT_MAX] = {
+ [EXEC_INPUT_NULL] = "null",
+ [EXEC_INPUT_TTY] = "tty",
+ [EXEC_INPUT_TTY_FORCE] = "tty-force",
+ [EXEC_INPUT_TTY_FAIL] = "tty-fail",
+ [EXEC_INPUT_SOCKET] = "socket"
+};
+
+static const char* const exec_output_table[_EXEC_OUTPUT_MAX] = {
+ [EXEC_OUTPUT_INHERIT] = "inherit",
+ [EXEC_OUTPUT_NULL] = "null",
+ [EXEC_OUTPUT_TTY] = "tty",
+ [EXEC_OUTPUT_SYSLOG] = "syslog",
+ [EXEC_OUTPUT_KERNEL] = "kernel",
+ [EXEC_OUTPUT_SOCKET] = "socket"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(exec_output, ExecOutput);
+
+DEFINE_STRING_TABLE_LOOKUP(exec_input, ExecInput);
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-07-26 15:30:04 +0000