| /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ |
| |
| /*** |
| 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 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 <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 <linux/oom.h> |
| #include <sys/poll.h> |
| #include <linux/seccomp-bpf.h> |
| #include <glob.h> |
| #include <libgen.h> |
| |
| #ifdef HAVE_PAM |
| #include <security/pam_appl.h> |
| #endif |
| |
| #include "execute.h" |
| #include "strv.h" |
| #include "macro.h" |
| #include "capability.h" |
| #include "util.h" |
| #include "log.h" |
| #include "sd-messages.h" |
| #include "ioprio.h" |
| #include "securebits.h" |
| #include "namespace.h" |
| #include "tcpwrap.h" |
| #include "exit-status.h" |
| #include "missing.h" |
| #include "utmp-wtmp.h" |
| #include "def.h" |
| #include "loopback-setup.h" |
| #include "path-util.h" |
| #include "syscall-list.h" |
| #include "env-util.h" |
| #include "fileio.h" |
| #include "unit.h" |
| #include "async.h" |
| |
| #define IDLE_TIMEOUT_USEC (5*USEC_PER_SEC) |
| #define IDLE_TIMEOUT2_USEC (1*USEC_PER_SEC) |
| |
| /* 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; |
| } |
| |
| _pure_ static const char *tty_path(const ExecContext *context) { |
| assert(context); |
| |
| if (context->tty_path) |
| return context->tty_path; |
| |
| return "/dev/console"; |
| } |
| |
| void exec_context_tty_reset(const ExecContext *context) { |
| assert(context); |
| |
| if (context->tty_vhangup) |
| terminal_vhangup(tty_path(context)); |
| |
| if (context->tty_reset) |
| reset_terminal(tty_path(context)); |
| |
| if (context->tty_vt_disallocate && context->tty_path) |
| vt_disallocate(context->tty_path); |
| } |
| |
| static bool is_terminal_output(ExecOutput o) { |
| return |
| o == EXEC_OUTPUT_TTY || |
| o == EXEC_OUTPUT_SYSLOG_AND_CONSOLE || |
| o == EXEC_OUTPUT_KMSG_AND_CONSOLE || |
| o == EXEC_OUTPUT_JOURNAL_AND_CONSOLE; |
| } |
| |
| void exec_context_serialize(const ExecContext *context, Unit *u, FILE *f) { |
| assert(context); |
| assert(u); |
| assert(f); |
| |
| if (context->tmp_dir) |
| unit_serialize_item(u, f, "tmp-dir", context->tmp_dir); |
| |
| if (context->var_tmp_dir) |
| unit_serialize_item(u, f, "var-tmp-dir", context->var_tmp_dir); |
| } |
| |
| 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, const char *unit_id, int nfd) { |
| int fd, r; |
| union sockaddr_union sa = { |
| .un.sun_family = AF_UNIX, |
| .un.sun_path = "/run/systemd/journal/stdout", |
| }; |
| |
| assert(context); |
| assert(output < _EXEC_OUTPUT_MAX); |
| assert(ident); |
| assert(nfd >= 0); |
| |
| fd = socket(AF_UNIX, SOCK_STREAM, 0); |
| if (fd < 0) |
| return -errno; |
| |
| r = connect(fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + strlen(sa.un.sun_path)); |
| if (r < 0) { |
| close_nointr_nofail(fd); |
| return -errno; |
| } |
| |
| if (shutdown(fd, SHUT_RD) < 0) { |
| close_nointr_nofail(fd); |
| return -errno; |
| } |
| |
| dprintf(fd, |
| "%s\n" |
| "%s\n" |
| "%i\n" |
| "%i\n" |
| "%i\n" |
| "%i\n" |
| "%i\n", |
| context->syslog_identifier ? context->syslog_identifier : ident, |
| unit_id, |
| context->syslog_priority, |
| !!context->syslog_level_prefix, |
| output == EXEC_OUTPUT_SYSLOG || output == EXEC_OUTPUT_SYSLOG_AND_CONSOLE, |
| output == EXEC_OUTPUT_KMSG || output == EXEC_OUTPUT_KMSG_AND_CONSOLE, |
| is_terminal_output(output)); |
| |
| 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(ExecInput std_input, int socket_fd, bool apply_tty_stdin) { |
| |
| if (is_terminal_input(std_input) && !apply_tty_stdin) |
| return EXEC_INPUT_NULL; |
| |
| if (std_input == EXEC_INPUT_SOCKET && socket_fd < 0) |
| return EXEC_INPUT_NULL; |
| |
| return std_input; |
| } |
| |
| static int fixup_output(ExecOutput std_output, int socket_fd) { |
| |
| if (std_output == EXEC_OUTPUT_SOCKET && socket_fd < 0) |
| return EXEC_OUTPUT_INHERIT; |
| |
| return std_output; |
| } |
| |
| static int setup_input(const ExecContext *context, int socket_fd, bool apply_tty_stdin) { |
| ExecInput i; |
| |
| assert(context); |
| |
| i = fixup_input(context->std_input, socket_fd, apply_tty_stdin); |
| |
| 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, |
| false, |
| (usec_t) -1)) < 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 fileno, int socket_fd, const char *ident, const char *unit_id, bool apply_tty_stdin) { |
| ExecOutput o; |
| ExecInput i; |
| int r; |
| |
| assert(context); |
| assert(ident); |
| |
| i = fixup_input(context->std_input, socket_fd, apply_tty_stdin); |
| o = fixup_output(context->std_output, socket_fd); |
| |
| if (fileno == STDERR_FILENO) { |
| ExecOutput e; |
| e = fixup_output(context->std_error, 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 && |
| i == EXEC_INPUT_NULL && |
| !is_terminal_input(context->std_input) && |
| getppid () != 1) |
| return fileno; |
| |
| /* Duplicate from stdout if possible */ |
| if (e == o || e == EXEC_OUTPUT_INHERIT) |
| return dup2(STDOUT_FILENO, fileno) < 0 ? -errno : fileno; |
| |
| o = e; |
| |
| } else if (o == EXEC_OUTPUT_INHERIT) { |
| /* If input got downgraded, inherit the original value */ |
| if (i == EXEC_INPUT_NULL && is_terminal_input(context->std_input)) |
| return open_terminal_as(tty_path(context), O_WRONLY, fileno); |
| |
| /* If the input is connected to anything that's not a /dev/null, inherit that... */ |
| if (i != EXEC_INPUT_NULL) |
| return dup2(STDIN_FILENO, fileno) < 0 ? -errno : fileno; |
| |
| /* If we are not started from PID 1 we just inherit STDOUT from our parent process. */ |
| if (getppid() != 1) |
| return fileno; |
| |
| /* We need to open /dev/null here anew, to get the right access mode. */ |
| return open_null_as(O_WRONLY, fileno); |
| } |
| |
| switch (o) { |
| |
| case EXEC_OUTPUT_NULL: |
| return open_null_as(O_WRONLY, fileno); |
| |
| case EXEC_OUTPUT_TTY: |
| if (is_terminal_input(i)) |
| return dup2(STDIN_FILENO, fileno) < 0 ? -errno : fileno; |
| |
| /* We don't reset the terminal if this is just about output */ |
| return open_terminal_as(tty_path(context), O_WRONLY, fileno); |
| |
| case EXEC_OUTPUT_SYSLOG: |
| case EXEC_OUTPUT_SYSLOG_AND_CONSOLE: |
| case EXEC_OUTPUT_KMSG: |
| case EXEC_OUTPUT_KMSG_AND_CONSOLE: |
| case EXEC_OUTPUT_JOURNAL: |
| case EXEC_OUTPUT_JOURNAL_AND_CONSOLE: |
| r = connect_logger_as(context, o, ident, unit_id, fileno); |
| if (r < 0) { |
| log_struct_unit(LOG_CRIT, unit_id, |
| "MESSAGE=Failed to connect std%s of %s to the journal socket: %s", |
| fileno == STDOUT_FILENO ? "out" : "err", |
| unit_id, strerror(-r), |
| "ERRNO=%d", -r, |
| NULL); |
| r = open_null_as(O_WRONLY, fileno); |
| } |
| return r; |
| |
| case EXEC_OUTPUT_SOCKET: |
| assert(socket_fd >= 0); |
| return dup2(socket_fd, fileno) < 0 ? -errno : 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(int *_saved_stdin, |
| int *_saved_stdout) { |
| int fd = -1, saved_stdin, saved_stdout = -1, r; |
| |
| assert(_saved_stdin); |
| assert(_saved_stdout); |
| |
| saved_stdin = fcntl(STDIN_FILENO, F_DUPFD, 3); |
| if (saved_stdin < 0) |
| return -errno; |
| |
| saved_stdout = fcntl(STDOUT_FILENO, F_DUPFD, 3); |
| if (saved_stdout < 0) { |
| r = errno; |
| goto fail; |
| } |
| |
| fd = acquire_terminal( |
| "/dev/console", |
| false, |
| false, |
| false, |
| DEFAULT_CONFIRM_USEC); |
| if (fd < 0) { |
| r = fd; |
| goto fail; |
| } |
| |
| r = chown_terminal(fd, getuid()); |
| if (r < 0) |
| goto fail; |
| |
| if (dup2(fd, STDIN_FILENO) < 0) { |
| r = -errno; |
| goto fail; |
| } |
| |
| if (dup2(fd, STDOUT_FILENO) < 0) { |
| r = -errno; |
| 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; |
| } |
| |
| _printf_attr_(1, 2) static int write_confirm_message(const char *format, ...) { |
| int fd; |
| va_list ap; |
| |
| assert(format); |
| |
| fd = open_terminal("/dev/console", O_WRONLY|O_NOCTTY|O_CLOEXEC); |
| if (fd < 0) |
| return fd; |
| |
| va_start(ap, format); |
| vdprintf(fd, format, ap); |
| va_end(ap); |
| |
| close_nointr_nofail(fd); |
| |
| return 0; |
| } |
| |
| static int restore_confirm_stdio(int *saved_stdin, |
| int *saved_stdout) { |
| |
| int r = 0; |
| |
| assert(saved_stdin); |
| assert(saved_stdout); |
| |
| release_terminal(); |
| |
| if (*saved_stdin >= 0) |
| if (dup2(*saved_stdin, STDIN_FILENO) < 0) |
| r = -errno; |
| |
| if (*saved_stdout >= 0) |
| if (dup2(*saved_stdout, STDOUT_FILENO) < 0) |
| r = -errno; |
| |
| if (*saved_stdin >= 0) |
| close_nointr_nofail(*saved_stdin); |
| |
| if (*saved_stdout >= 0) |
| close_nointr_nofail(*saved_stdout); |
| |
| return r; |
| } |
| |
| static int ask_for_confirmation(char *response, char **argv) { |
| int saved_stdout = -1, saved_stdin = -1, r; |
| char *line; |
| |
| r = setup_confirm_stdio(&saved_stdin, &saved_stdout); |
| if (r < 0) |
| return r; |
| |
| line = exec_command_line(argv); |
| if (!line) |
| return -ENOMEM; |
| |
| r = ask(response, "yns", "Execute %s? [Yes, No, Skip] ", line); |
| free(line); |
| |
| restore_confirm_stdio(&saved_stdin, &saved_stdout); |
| |
| return r; |
| } |
| |
| static int enforce_groups(const ExecContext *context, const char *username, gid_t gid) { |
| bool keep_groups = false; |
| int r; |
| |
| assert(context); |
| |
| /* Lookup and set GID and supplementary group list. Here too |
| * we avoid NSS lookups for gid=0. */ |
| |
| if (context->group || username) { |
| |
| if (context->group) { |
| const char *g = context->group; |
| |
| if ((r = get_group_creds(&g, &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 */ |
| assert_se((ngroups_max = (int) sysconf(_SC_NGROUPS_MAX)) > 0); |
| |
| 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) { |
| const char *g; |
| |
| if (k >= ngroups_max) { |
| free(gids); |
| return -E2BIG; |
| } |
| |
| g = *i; |
| r = get_group_creds(&g, gids+k); |
| if (r < 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, while we drop privileges. */ |
| if (uid != 0) { |
| int sb = context->secure_bits | 1<<SECURE_KEEP_CAPS; |
| |
| if (prctl(PR_GET_SECUREBITS) != sb) |
| if (prctl(PR_SET_SECUREBITS, sb) < 0) |
| return -errno; |
| } |
| |
| /* Second step: set the capabilities. 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; |
| } |
| |
| #ifdef HAVE_PAM |
| |
| static int null_conv( |
| int num_msg, |
| const struct pam_message **msg, |
| struct pam_response **resp, |
| void *appdata_ptr) { |
| |
| /* We don't support conversations */ |
| |
| return PAM_CONV_ERR; |
| } |
| |
| static int setup_pam( |
| const char *name, |
| const char *user, |
| uid_t uid, |
| const char *tty, |
| char ***pam_env, |
| int fds[], unsigned n_fds) { |
| |
| static const struct pam_conv conv = { |
| .conv = null_conv, |
| .appdata_ptr = NULL |
| }; |
| |
| pam_handle_t *handle = NULL; |
| sigset_t ss, old_ss; |
| int pam_code = PAM_SUCCESS; |
| int err; |
| char **e = NULL; |
| bool close_session = false; |
| pid_t pam_pid = 0, parent_pid; |
| |
| assert(name); |
| assert(user); |
| assert(pam_env); |
| |
| /* We set up PAM in the parent process, then fork. The child |
| * will then stay around until killed via PR_GET_PDEATHSIG or |
| * systemd via the cgroup logic. It will then remove the PAM |
| * session again. The parent process will exec() the actual |
| * daemon. We do things this way to ensure that the main PID |
| * of the daemon is the one we initially fork()ed. */ |
| |
| pam_code = pam_start(name, user, &conv, &handle); |
| if (pam_code != PAM_SUCCESS) { |
| handle = NULL; |
| goto fail; |
| } |
| |
| if (tty) { |
| pam_code = pam_set_item(handle, PAM_TTY, tty); |
| if (pam_code != PAM_SUCCESS) |
| goto fail; |
| } |
| |
| pam_code = pam_acct_mgmt(handle, PAM_SILENT); |
| if (pam_code != PAM_SUCCESS) |
| goto fail; |
| |
| pam_code = pam_open_session(handle, PAM_SILENT); |
| if (pam_code != PAM_SUCCESS) |
| goto fail; |
| |
| close_session = true; |
| |
| e = pam_getenvlist(handle); |
| if (!e) { |
| pam_code = PAM_BUF_ERR; |
| goto fail; |
| } |
| |
| /* Block SIGTERM, so that we know that it won't get lost in |
| * the child */ |
| if (sigemptyset(&ss) < 0 || |
| sigaddset(&ss, SIGTERM) < 0 || |
| sigprocmask(SIG_BLOCK, &ss, &old_ss) < 0) |
| goto fail; |
| |
| parent_pid = getpid(); |
| |
| pam_pid = fork(); |
| if (pam_pid < 0) |
| goto fail; |
| |
| if (pam_pid == 0) { |
| int sig; |
| int r = EXIT_PAM; |
| |
| /* The child's job is to reset the PAM session on |
| * termination */ |
| |
| /* This string must fit in 10 chars (i.e. the length |
| * of "/sbin/init"), to look pretty in /bin/ps */ |
| rename_process("(sd-pam)"); |
| |
| /* Make sure we don't keep open the passed fds in this |
| child. We assume that otherwise only those fds are |
| open here that have been opened by PAM. */ |
| close_many(fds, n_fds); |
| |
| /* Drop privileges - we don't need any to pam_close_session |
| * and this will make PR_SET_PDEATHSIG work in most cases. |
| * If this fails, ignore the error - but expect sd-pam threads |
| * to fail to exit normally */ |
| if (setresuid(uid, uid, uid) < 0) |
| log_error("Error: Failed to setresuid() in sd-pam: %s", strerror(-r)); |
| |
| /* Wait until our parent died. This will only work if |
| * the above setresuid() succeeds, otherwise the kernel |
| * will not allow unprivileged parents kill their privileged |
| * children this way. We rely on the control groups kill logic |
| * to do the rest for us. */ |
| if (prctl(PR_SET_PDEATHSIG, SIGTERM) < 0) |
| goto child_finish; |
| |
| /* Check if our parent process might already have |
| * died? */ |
| if (getppid() == parent_pid) { |
| for (;;) { |
| if (sigwait(&ss, &sig) < 0) { |
| if (errno == EINTR) |
| continue; |
| |
| goto child_finish; |
| } |
| |
| assert(sig == SIGTERM); |
| break; |
| } |
| } |
| |
| /* If our parent died we'll end the session */ |
| if (getppid() != parent_pid) { |
| pam_code = pam_close_session(handle, PAM_DATA_SILENT); |
| if (pam_code != PAM_SUCCESS) |
| goto child_finish; |
| } |
| |
| r = 0; |
| |
| child_finish: |
| pam_end(handle, pam_code | PAM_DATA_SILENT); |
| _exit(r); |
| } |
| |
| /* If the child was forked off successfully it will do all the |
| * cleanups, so forget about the handle here. */ |
| handle = NULL; |
| |
| /* Unblock SIGTERM again in the parent */ |
| if (sigprocmask(SIG_SETMASK, &old_ss, NULL) < 0) |
| goto fail; |
| |
| /* We close the log explicitly here, since the PAM modules |
| * might have opened it, but we don't want this fd around. */ |
| closelog(); |
| |
| *pam_env = e; |
| e = NULL; |
| |
| return 0; |
| |
| fail: |
| if (pam_code != PAM_SUCCESS) |
| err = -EPERM; /* PAM errors do not map to errno */ |
| else |
| err = -errno; |
| |
| if (handle) { |
| if (close_session) |
| pam_code = pam_close_session(handle, PAM_DATA_SILENT); |
| |
| pam_end(handle, pam_code | PAM_DATA_SILENT); |
| } |
| |
| strv_free(e); |
| |
| closelog(); |
| |
| if (pam_pid > 1) { |
| kill(pam_pid, SIGTERM); |
| kill(pam_pid, SIGCONT); |
| } |
| |
| return err; |
| } |
| #endif |
| |
| static void rename_process_from_path(const char *path) { |
| char process_name[11]; |
| const char *p; |
| size_t l; |
| |
| /* This resulting string must fit in 10 chars (i.e. the length |
| * of "/sbin/init") to look pretty in /bin/ps */ |
| |
| p = path_get_file_name(path); |
| if (isempty(p)) { |
| rename_process("(...)"); |
| return; |
| } |
| |
| l = strlen(p); |
| if (l > 8) { |
| /* The end of the process name is usually more |
| * interesting, since the first bit might just be |
| * "systemd-" */ |
| p = p + l - 8; |
| l = 8; |
| } |
| |
| process_name[0] = '('; |
| memcpy(process_name+1, p, l); |
| process_name[1+l] = ')'; |
| process_name[1+l+1] = 0; |
| |
| rename_process(process_name); |
| } |
| |
| static int apply_seccomp(uint32_t *syscall_filter) { |
| static const struct sock_filter header[] = { |
| VALIDATE_ARCHITECTURE, |
| EXAMINE_SYSCALL |
| }; |
| static const struct sock_filter footer[] = { |
| _KILL_PROCESS |
| }; |
| |
| int i; |
| unsigned n; |
| struct sock_filter *f; |
| struct sock_fprog prog = {}; |
| |
| assert(syscall_filter); |
| |
| /* First: count the syscalls to check for */ |
| for (i = 0, n = 0; i < syscall_max(); i++) |
| if (syscall_filter[i >> 4] & (1 << (i & 31))) |
| n++; |
| |
| /* Second: build the filter program from a header the syscall |
| * matches and the footer */ |
| f = alloca(sizeof(struct sock_filter) * (ELEMENTSOF(header) + 2*n + ELEMENTSOF(footer))); |
| memcpy(f, header, sizeof(header)); |
| |
| for (i = 0, n = 0; i < syscall_max(); i++) |
| if (syscall_filter[i >> 4] & (1 << (i & 31))) { |
| struct sock_filter item[] = { |
| BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, INDEX_TO_SYSCALL(i), 0, 1), |
| BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_ALLOW) |
| }; |
| |
| assert_cc(ELEMENTSOF(item) == 2); |
| |
| f[ELEMENTSOF(header) + 2*n] = item[0]; |
| f[ELEMENTSOF(header) + 2*n+1] = item[1]; |
| |
| n++; |
| } |
| |
| memcpy(f + (ELEMENTSOF(header) + 2*n), footer, sizeof(footer)); |
| |
| /* Third: install the filter */ |
| prog.len = ELEMENTSOF(header) + ELEMENTSOF(footer) + 2*n; |
| prog.filter = f; |
| if (prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog) < 0) |
| return -errno; |
| |
| return 0; |
| } |
| |
| static void do_idle_pipe_dance(int idle_pipe[4]) { |
| assert(idle_pipe); |
| |
| if (idle_pipe[1] >= 0) |
| close_nointr_nofail(idle_pipe[1]); |
| if (idle_pipe[2] >= 0) |
| close_nointr_nofail(idle_pipe[2]); |
| |
| if (idle_pipe[0] >= 0) { |
| int r; |
| |
| r = fd_wait_for_event(idle_pipe[0], POLLHUP, IDLE_TIMEOUT_USEC); |
| |
| if (idle_pipe[3] >= 0 && r == 0 /* timeout */) { |
| /* Signal systemd that we are bored and want to continue. */ |
| write(idle_pipe[3], "x", 1); |
| |
| /* Wait for systemd to react to the signal above. */ |
| fd_wait_for_event(idle_pipe[0], POLLHUP, IDLE_TIMEOUT2_USEC); |
| } |
| |
| close_nointr_nofail(idle_pipe[0]); |
| |
| } |
| |
| if (idle_pipe[3] >= 0) |
| close_nointr_nofail(idle_pipe[3]); |
| } |
| |
| int exec_spawn(ExecCommand *command, |
| char **argv, |
| ExecContext *context, |
| int fds[], unsigned n_fds, |
| char **environment, |
| bool apply_permissions, |
| bool apply_chroot, |
| bool apply_tty_stdin, |
| bool confirm_spawn, |
| CGroupControllerMask cgroup_supported, |
| const char *cgroup_path, |
| const char *unit_id, |
| int idle_pipe[4], |
| pid_t *ret) { |
| |
| _cleanup_strv_free_ char **files_env = NULL; |
| int socket_fd; |
| char *line; |
| pid_t pid; |
| int r; |
| |
| 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; |
| |
| r = exec_context_load_environment(context, &files_env); |
| if (r < 0) { |
| log_struct_unit(LOG_ERR, |
| unit_id, |
| "MESSAGE=Failed to load environment files: %s", strerror(-r), |
| "ERRNO=%d", -r, |
| NULL); |
| return r; |
| } |
| |
| if (!argv) |
| argv = command->argv; |
| |
| line = exec_command_line(argv); |
| if (!line) |
| return log_oom(); |
| |
| log_struct_unit(LOG_DEBUG, |
| unit_id, |
| "EXECUTABLE=%s", command->path, |
| "MESSAGE=About to execute: %s", line, |
| NULL); |
| free(line); |
| |
| if (context->private_tmp && !context->tmp_dir && !context->var_tmp_dir) { |
| r = setup_tmpdirs(&context->tmp_dir, &context->var_tmp_dir); |
| if (r < 0) |
| return r; |
| } |
| |
| pid = fork(); |
| if (pid < 0) |
| return -errno; |
| |
| if (pid == 0) { |
| int i, err; |
| sigset_t ss; |
| const char *username = NULL, *home = NULL; |
| uid_t uid = (uid_t) -1; |
| gid_t gid = (gid_t) -1; |
| _cleanup_strv_free_ char **our_env = NULL, **pam_env = NULL, |
| **final_env = NULL, **final_argv = NULL; |
| unsigned n_env = 0; |
| |
| /* child */ |
| |
| rename_process_from_path(command->path); |
| |
| /* We reset exactly these signals, since they are the |
| * only ones we set to SIG_IGN in the main daemon. All |
| * others we leave untouched because we set them to |
| * SIG_DFL or a valid handler initially, both of which |
| * will be demoted to SIG_DFL. */ |
| default_signals(SIGNALS_CRASH_HANDLER, |
| SIGNALS_IGNORE, -1); |
| |
| if (context->ignore_sigpipe) |
| ignore_signals(SIGPIPE, -1); |
| |
| assert_se(sigemptyset(&ss) == 0); |
| if (sigprocmask(SIG_SETMASK, &ss, NULL) < 0) { |
| err = -errno; |
| r = EXIT_SIGNAL_MASK; |
| goto fail_child; |
| } |
| |
| if (idle_pipe) |
| do_idle_pipe_dance(idle_pipe); |
| |
| /* Close sockets very early to make sure we don't |
| * block init reexecution because it cannot bind its |
| * sockets */ |
| log_forget_fds(); |
| err = close_all_fds(socket_fd >= 0 ? &socket_fd : fds, |
| socket_fd >= 0 ? 1 : n_fds); |
| if (err < 0) { |
| r = EXIT_FDS; |
| goto fail_child; |
| } |
| |
| if (!context->same_pgrp) |
| if (setsid() < 0) { |
| err = -errno; |
| r = EXIT_SETSID; |
| goto fail_child; |
| } |
| |
| if (context->tcpwrap_name) { |
| if (socket_fd >= 0) |
| if (!socket_tcpwrap(socket_fd, context->tcpwrap_name)) { |
| err = -EACCES; |
| r = EXIT_TCPWRAP; |
| goto fail_child; |
| } |
| |
| for (i = 0; i < (int) n_fds; i++) { |
| if (!socket_tcpwrap(fds[i], context->tcpwrap_name)) { |
| err = -EACCES; |
| r = EXIT_TCPWRAP; |
| goto fail_child; |
| } |
| } |
| } |
| |
| exec_context_tty_reset(context); |
| |
| if (confirm_spawn) { |
| char response; |
| |
| err = ask_for_confirmation(&response, argv); |
| if (err == -ETIMEDOUT) |
| write_confirm_message("Confirmation question timed out, assuming positive response.\n"); |
| else if (err < 0) |
| write_confirm_message("Couldn't ask confirmation question, assuming positive response: %s\n", strerror(-err)); |
| else if (response == 's') { |
| write_confirm_message("Skipping execution.\n"); |
| err = -ECANCELED; |
| r = EXIT_CONFIRM; |
| goto fail_child; |
| } else if (response == 'n') { |
| write_confirm_message("Failing execution.\n"); |
| err = r = 0; |
| goto fail_child; |
| } |
| } |
| |
| /* If a socket is connected to STDIN/STDOUT/STDERR, we |
| * must sure to drop O_NONBLOCK */ |
| if (socket_fd >= 0) |
| fd_nonblock(socket_fd, false); |
| |
| err = setup_input(context, socket_fd, apply_tty_stdin); |
| if (err < 0) { |
| r = EXIT_STDIN; |
| goto fail_child; |
| } |
| |
| err = setup_output(context, STDOUT_FILENO, socket_fd, path_get_file_name(command->path), unit_id, apply_tty_stdin); |
| if (err < 0) { |
| r = EXIT_STDOUT; |
| goto fail_child; |
| } |
| |
| err = setup_output(context, STDERR_FILENO, socket_fd, path_get_file_name(command->path), unit_id, apply_tty_stdin); |
| if (err < 0) { |
| r = EXIT_STDERR; |
| goto fail_child; |
| } |
| |
| if (cgroup_path) { |
| err = cg_attach_everywhere(cgroup_supported, cgroup_path, 0); |
| if (err < 0) { |
| r = EXIT_CGROUP; |
| goto fail_child; |
| } |
| } |
| |
| if (context->oom_score_adjust_set) { |
| char t[16]; |
| |
| snprintf(t, sizeof(t), "%i", context->oom_score_adjust); |
| char_array_0(t); |
| |
| if (write_string_file("/proc/self/oom_score_adj", t) < 0) { |
| err = -errno; |
| r = EXIT_OOM_ADJUST; |
| goto fail_child; |
| } |
| } |
| |
| if (context->nice_set) |
| if (setpriority(PRIO_PROCESS, 0, context->nice) < 0) { |
| err = -errno; |
| r = EXIT_NICE; |
| goto fail_child; |
| } |
| |
| if (context->cpu_sched_set) { |
| struct sched_param param = { |
| .sched_priority = context->cpu_sched_priority, |
| }; |
| |
| r = sched_setscheduler(0, |
| context->cpu_sched_policy | |
| (context->cpu_sched_reset_on_fork ? |
| SCHED_RESET_ON_FORK : 0), |
| ¶m); |
| if (r < 0) { |
| err = -errno; |
| r = EXIT_SETSCHEDULER; |
| goto fail_child; |
| } |
| } |
| |
| if (context->cpuset) |
| if (sched_setaffinity(0, CPU_ALLOC_SIZE(context->cpuset_ncpus), context->cpuset) < 0) { |
| err = -errno; |
| r = EXIT_CPUAFFINITY; |
| goto fail_child; |
| } |
| |
| if (context->ioprio_set) |
| if (ioprio_set(IOPRIO_WHO_PROCESS, 0, context->ioprio) < 0) { |
| err = -errno; |
| r = EXIT_IOPRIO; |
| goto fail_child; |
| } |
| |
| if (context->timer_slack_nsec != (nsec_t) -1) |
| if (prctl(PR_SET_TIMERSLACK, context->timer_slack_nsec) < 0) { |
| err = -errno; |
| r = EXIT_TIMERSLACK; |
| goto fail_child; |
| } |
| |
| if (context->utmp_id) |
| utmp_put_init_process(context->utmp_id, getpid(), getsid(0), context->tty_path); |
| |
| if (context->user) { |
| username = context->user; |
| err = get_user_creds(&username, &uid, &gid, &home, NULL); |
| if (err < 0) { |
| r = EXIT_USER; |
| goto fail_child; |
| } |
| |
| if (is_terminal_input(context->std_input)) { |
| err = chown_terminal(STDIN_FILENO, uid); |
| if (err < 0) { |
| r = EXIT_STDIN; |
| goto fail_child; |
| } |
| } |
| } |
| |
| #ifdef HAVE_PAM |
| if (cgroup_path && context->user && context->pam_name) { |
| err = cg_set_task_access(SYSTEMD_CGROUP_CONTROLLER, cgroup_path, 0644, uid, gid); |
| if (err < 0) { |
| r = EXIT_CGROUP; |
| goto fail_child; |
| } |
| |
| |
| err = cg_set_group_access(SYSTEMD_CGROUP_CONTROLLER, cgroup_path, 0755, uid, gid); |
| if (err < 0) { |
| r = EXIT_CGROUP; |
| goto fail_child; |
| } |
| } |
| #endif |
| |
| if (apply_permissions) { |
| err = enforce_groups(context, username, gid); |
| if (err < 0) { |
| r = EXIT_GROUP; |
| goto fail_child; |
| } |
| } |
| |
| umask(context->umask); |
| |
| #ifdef HAVE_PAM |
| if (apply_permissions && context->pam_name && username) { |
| err = setup_pam(context->pam_name, username, uid, context->tty_path, &pam_env, fds, n_fds); |
| if (err < 0) { |
| r = EXIT_PAM; |
| goto fail_child; |
| } |
| } |
| #endif |
| if (context->private_network) { |
| if (unshare(CLONE_NEWNET) < 0) { |
| err = -errno; |
| r = EXIT_NETWORK; |
| goto fail_child; |
| } |
| |
| loopback_setup(); |
| } |
| |
| if (strv_length(context->read_write_dirs) > 0 || |
| strv_length(context->read_only_dirs) > 0 || |
| strv_length(context->inaccessible_dirs) > 0 || |
| context->mount_flags != 0 || |
| context->private_tmp) { |
| err = setup_namespace(context->read_write_dirs, |
| context->read_only_dirs, |
| context->inaccessible_dirs, |
| context->tmp_dir, |
| context->var_tmp_dir, |
| context->private_tmp, |
| context->mount_flags); |
| if (err < 0) { |
| r = EXIT_NAMESPACE; |
| goto fail_child; |
| } |
| } |
| |
| if (apply_chroot) { |
| if (context->root_directory) |
| if (chroot(context->root_directory) < 0) { |
| err = -errno; |
| r = EXIT_CHROOT; |
| goto fail_child; |
| } |
| |
| if (chdir(context->working_directory ? context->working_directory : "/") < 0) { |
| err = -errno; |
| r = EXIT_CHDIR; |
| goto fail_child; |
| } |
| } else { |
| _cleanup_free_ char *d = NULL; |
| |
| if (asprintf(&d, "%s/%s", |
| context->root_directory ? context->root_directory : "", |
| context->working_directory ? context->working_directory : "") < 0) { |
| err = -ENOMEM; |
| r = EXIT_MEMORY; |
| goto fail_child; |
| } |
| |
| if (chdir(d) < 0) { |
| err = -errno; |
| r = EXIT_CHDIR; |
| goto fail_child; |
| } |
| } |
| |
| /* We repeat the fd closing here, to make sure that |
| * nothing is leaked from the PAM modules */ |
| err = close_all_fds(fds, n_fds); |
| if (err >= 0) |
| err = shift_fds(fds, n_fds); |
| if (err >= 0) |
| err = flags_fds(fds, n_fds, context->non_blocking); |
| if (err < 0) { |
| r = EXIT_FDS; |
| goto fail_child; |
| } |
| |
| if (apply_permissions) { |
| |
| for (i = 0; i < RLIMIT_NLIMITS; i++) { |
| if (!context->rlimit[i]) |
| continue; |
| |
| if (setrlimit_closest(i, context->rlimit[i]) < 0) { |
| err = -errno; |
| r = EXIT_LIMITS; |
| goto fail_child; |
| } |
| } |
| |
| if (context->capability_bounding_set_drop) { |
| err = capability_bounding_set_drop(context->capability_bounding_set_drop, false); |
| if (err < 0) { |
| r = EXIT_CAPABILITIES; |
| goto fail_child; |
| } |
| } |
| |
| if (context->user) { |
| err = enforce_user(context, uid); |
| if (err < 0) { |
| r = EXIT_USER; |
| goto fail_child; |
| } |
| } |
| |
| /* PR_GET_SECUREBITS is not privileged, 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) { |
| err = -errno; |
| r = EXIT_SECUREBITS; |
| goto fail_child; |
| } |
| |
| if (context->capabilities) |
| if (cap_set_proc(context->capabilities) < 0) { |
| err = -errno; |
| r = EXIT_CAPABILITIES; |
| goto fail_child; |
| } |
| |
| if (context->no_new_privileges) |
| if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0) < 0) { |
| err = -errno; |
| r = EXIT_NO_NEW_PRIVILEGES; |
| goto fail_child; |
| } |
| |
| if (context->syscall_filter) { |
| err = apply_seccomp(context->syscall_filter); |
| if (err < 0) { |
| r = EXIT_SECCOMP; |
| goto fail_child; |
| } |
| } |
| } |
| |
| our_env = new0(char*, 7); |
| if (!our_env) { |
| err = -ENOMEM; |
| r = EXIT_MEMORY; |
| goto fail_child; |
| } |
| |
| if (n_fds > 0) |
| if (asprintf(our_env + n_env++, "LISTEN_PID=%lu", (unsigned long) getpid()) < 0 || |
| asprintf(our_env + n_env++, "LISTEN_FDS=%u", n_fds) < 0) { |
| err = -ENOMEM; |
| r = EXIT_MEMORY; |
| goto fail_child; |
| } |
| |
| if (home) |
| if (asprintf(our_env + n_env++, "HOME=%s", home) < 0) { |
| err = -ENOMEM; |
| r = EXIT_MEMORY; |
| goto fail_child; |
| } |
| |
| if (username) |
| if (asprintf(our_env + n_env++, "LOGNAME=%s", username) < 0 || |
| asprintf(our_env + n_env++, "USER=%s", username) < 0) { |
| err = -ENOMEM; |
| r = EXIT_MEMORY; |
| goto fail_child; |
| } |
| |
| if (is_terminal_input(context->std_input) || |
| context->std_output == EXEC_OUTPUT_TTY || |
| context->std_error == EXEC_OUTPUT_TTY) |
| if (!(our_env[n_env++] = strdup(default_term_for_tty(tty_path(context))))) { |
| err = -ENOMEM; |
| r = EXIT_MEMORY; |
| goto fail_child; |
| } |
| |
| assert(n_env <= 7); |
| |
| final_env = strv_env_merge(5, |
| environment, |
| our_env, |
| context->environment, |
| files_env, |
| pam_env, |
| NULL); |
| if (!final_env) { |
| err = -ENOMEM; |
| r = EXIT_MEMORY; |
| goto fail_child; |
| } |
| |
| final_argv = replace_env_argv(argv, final_env); |
| if (!final_argv) { |
| err = -ENOMEM; |
| r = EXIT_MEMORY; |
| goto fail_child; |
| } |
| |
| final_env = strv_env_clean(final_env); |
| |
| if (_unlikely_(log_get_max_level() >= LOG_PRI(LOG_DEBUG))) { |
| line = exec_command_line(final_argv); |
| if (line) { |
| log_open(); |
| log_struct_unit(LOG_DEBUG, |
| unit_id, |
| "EXECUTABLE=%s", command->path, |
| "MESSAGE=Executing: %s", line, |
| NULL); |
| log_close(); |
| free(line); |
| line = NULL; |
| } |
| } |
| execve(command->path, final_argv, final_env); |
| err = -errno; |
| r = EXIT_EXEC; |
| |
| fail_child: |
| if (r != 0) { |
| log_open(); |
| log_struct(LOG_ERR, MESSAGE_ID(SD_MESSAGE_SPAWN_FAILED), |
| "EXECUTABLE=%s", command->path, |
| "MESSAGE=Failed at step %s spawning %s: %s", |
| exit_status_to_string(r, EXIT_STATUS_SYSTEMD), |
| command->path, strerror(-err), |
| "ERRNO=%d", -err, |
| NULL); |
| log_close(); |
| } |
| |
| _exit(r); |
| } |
| |
| log_struct_unit(LOG_DEBUG, |
| unit_id, |
| "MESSAGE=Forked %s as %lu", |
| command->path, (unsigned long) pid, |
| NULL); |
| |
| /* 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_path) |
| cg_attach(SYSTEMD_CGROUP_CONTROLLER, cgroup_path, pid); |
| |
| exec_status_start(&command->exec_status, pid); |
| |
| *ret = pid; |
| return 0; |
| } |
| |
| void exec_context_init(ExecContext *c) { |
| assert(c); |
| |
| c->umask = 0022; |
| c->ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 0); |
| c->cpu_sched_policy = SCHED_OTHER; |
| c->syslog_priority = LOG_DAEMON|LOG_INFO; |
| c->syslog_level_prefix = true; |
| c->ignore_sigpipe = true; |
| c->timer_slack_nsec = (nsec_t) -1; |
| } |
| |
| static void *remove_tmpdir_thread(void *p) { |
| int r; |
| _cleanup_free_ char *dirp = p; |
| char *dir; |
| |
| assert(dirp); |
| |
| r = rm_rf_dangerous(dirp, false, true, false); |
| dir = dirname(dirp); |
| if (r < 0) |
| log_warning("Failed to remove content of temporary directory %s: %s", |
| dir, strerror(-r)); |
| else { |
| r = rmdir(dir); |
| if (r < 0) |
| log_warning("Failed to remove temporary directory %s: %s", |
| dir, strerror(-r)); |
| } |
| |
| return NULL; |
| } |
| |
| void exec_context_tmp_dirs_done(ExecContext *c) { |
| char* dirs[] = {c->tmp_dir ? c->tmp_dir : c->var_tmp_dir, |
| c->tmp_dir ? c->var_tmp_dir : NULL, |
| NULL}; |
| char **dirp; |
| |
| for(dirp = dirs; *dirp; dirp++) { |
| log_debug("Spawning thread to nuke %s", *dirp); |
| asynchronous_job(remove_tmpdir_thread, *dirp); |
| } |
| |
| c->tmp_dir = c->var_tmp_dir = NULL; |
| } |
| |
| void exec_context_done(ExecContext *c, bool reloading_or_reexecuting) { |
| unsigned l; |
| |
| assert(c); |
| |
| strv_free(c->environment); |
| c->environment = NULL; |
| |
| strv_free(c->environment_files); |
| c->environment_files = 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->tcpwrap_name); |
| c->tcpwrap_name = 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; |
| |
| free(c->pam_name); |
| c->pam_name = 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; |
| |
| if (c->cpuset) |
| CPU_FREE(c->cpuset); |
| |
| free(c->utmp_id); |
| c->utmp_id = NULL; |
| |
| free(c->syscall_filter); |
| c->syscall_filter = NULL; |
| |
| if (!reloading_or_reexecuting) |
| exec_context_tmp_dirs_done(c); |
| } |
| |
| 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; |
| } |
| } |
| |
| int exec_context_load_environment(const ExecContext *c, char ***l) { |
| char **i, **r = NULL; |
| |
| assert(c); |
| assert(l); |
| |
| STRV_FOREACH(i, c->environment_files) { |
| char *fn; |
| int k; |
| bool ignore = false; |
| char **p; |
| _cleanup_globfree_ glob_t pglob = {}; |
| int count, n; |
| |
| fn = *i; |
| |
| if (fn[0] == '-') { |
| ignore = true; |
| fn ++; |
| } |
| |
| if (!path_is_absolute(fn)) { |
| if (ignore) |
| continue; |
| |
| strv_free(r); |
| return -EINVAL; |
| } |
| |
| /* Filename supports globbing, take all matching files */ |
| errno = 0; |
| if (glob(fn, 0, NULL, &pglob) != 0) { |
| if (ignore) |
| continue; |
| |
| strv_free(r); |
| return errno ? -errno : -EINVAL; |
| } |
| count = pglob.gl_pathc; |
| if (count == 0) { |
| if (ignore) |
| continue; |
| |
| strv_free(r); |
| return -EINVAL; |
| } |
| for (n = 0; n < count; n++) { |
| k = load_env_file(pglob.gl_pathv[n], NULL, &p); |
| if (k < 0) { |
| if (ignore) |
| continue; |
| |
| strv_free(r); |
| return k; |
| } |
| /* Log invalid environment variables with filename */ |
| if (p) |
| p = strv_env_clean_log(p, pglob.gl_pathv[n]); |
| |
| if (r == NULL) |
| r = p; |
| else { |
| char **m; |
| |
| m = strv_env_merge(2, r, p); |
| strv_free(r); |
| strv_free(p); |
| if (!m) |
| return -ENOMEM; |
| |
| r = m; |
| } |
| } |
| } |
| |
| *l = r; |
| |
| return 0; |
| } |
| |
| static bool tty_may_match_dev_console(const char *tty) { |
| char *active = NULL, *console; |
| bool b; |
| |
| if (startswith(tty, "/dev/")) |
| tty += 5; |
| |
| /* trivial identity? */ |
| if (streq(tty, "console")) |
| return true; |
| |
| console = resolve_dev_console(&active); |
| /* if we could not resolve, assume it may */ |
| if (!console) |
| return true; |
| |
| /* "tty0" means the active VC, so it may be the same sometimes */ |
| b = streq(console, tty) || (streq(console, "tty0") && tty_is_vc(tty)); |
| free(active); |
| |
| return b; |
| } |
| |
| bool exec_context_may_touch_console(ExecContext *ec) { |
| return (ec->tty_reset || ec->tty_vhangup || ec->tty_vt_disallocate || |
| is_terminal_input(ec->std_input) || |
| is_terminal_output(ec->std_output) || |
| is_terminal_output(ec->std_error)) && |
| tty_may_match_dev_console(tty_path(ec)); |
| } |
| |
| 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); |
| |
| prefix = strempty(prefix); |
| |
| fprintf(f, |
| "%sUMask: %04o\n" |
| "%sWorkingDirectory: %s\n" |
| "%sRootDirectory: %s\n" |
| "%sNonBlocking: %s\n" |
| "%sPrivateTmp: %s\n" |
| "%sPrivateNetwork: %s\n" |
| "%sIgnoreSIGPIPE: %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), |
| prefix, yes_no(c->private_network), |
| prefix, yes_no(c->ignore_sigpipe)); |
| |
| STRV_FOREACH(e, c->environment) |
| fprintf(f, "%sEnvironment: %s\n", prefix, *e); |
| |
| STRV_FOREACH(e, c->environment_files) |
| fprintf(f, "%sEnvironmentFile: %s\n", prefix, *e); |
| |
| if (c->tcpwrap_name) |
| fprintf(f, |
| "%sTCPWrapName: %s\n", |
| prefix, c->tcpwrap_name); |
| |
| if (c->nice_set) |
| fprintf(f, |
| "%sNice: %i\n", |
| prefix, c->nice); |
| |
| if (c->oom_score_adjust_set) |
| fprintf(f, |
| "%sOOMScoreAdjust: %i\n", |
| prefix, c->oom_score_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) { |
| char *class_str; |
| int r; |
| |
| r = ioprio_class_to_string_alloc(IOPRIO_PRIO_CLASS(c->ioprio), &class_str); |
| if (r < 0) |
| class_str = NULL; |
| fprintf(f, |
| "%sIOSchedulingClass: %s\n" |
| "%sIOPriority: %i\n", |
| prefix, strna(class_str), |
| prefix, (int) IOPRIO_PRIO_DATA(c->ioprio)); |
| free(class_str); |
| } |
| |
| if (c->cpu_sched_set) { |
| char *policy_str; |
| int r; |
| |
| r = sched_policy_to_string_alloc(c->cpu_sched_policy, &policy_str); |
| if (r < 0) |
| policy_str = NULL; |
| fprintf(f, |
| "%sCPUSchedulingPolicy: %s\n" |
| "%sCPUSchedulingPriority: %i\n" |
| "%sCPUSchedulingResetOnFork: %s\n", |
| prefix, strna(policy_str), |
| prefix, c->cpu_sched_priority, |
| prefix, yes_no(c->cpu_sched_reset_on_fork)); |
| free(policy_str); |
| } |
| |
| if (c->cpuset) { |
| fprintf(f, "%sCPUAffinity:", prefix); |
| for (i = 0; i < c->cpuset_ncpus; i++) |
| if (CPU_ISSET_S(i, CPU_ALLOC_SIZE(c->cpuset_ncpus), c->cpuset)) |
| fprintf(f, " %i", i); |
| fputs("\n", f); |
| } |
| |
| if (c->timer_slack_nsec != (nsec_t) -1) |
| fprintf(f, "%sTimerSlackNSec: %lu\n", prefix, (unsigned long)c->timer_slack_nsec); |
| |
| 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" |
| "%sTTYReset: %s\n" |
| "%sTTYVHangup: %s\n" |
| "%sTTYVTDisallocate: %s\n", |
| prefix, c->tty_path, |
| prefix, yes_no(c->tty_reset), |
| prefix, yes_no(c->tty_vhangup), |
| prefix, yes_no(c->tty_vt_disallocate)); |
| |
| if (c->std_output == EXEC_OUTPUT_SYSLOG || c->std_output == EXEC_OUTPUT_KMSG || c->std_output == EXEC_OUTPUT_JOURNAL || |
| c->std_output == EXEC_OUTPUT_SYSLOG_AND_CONSOLE || c->std_output == EXEC_OUTPUT_KMSG_AND_CONSOLE || c->std_output == EXEC_OUTPUT_JOURNAL_AND_CONSOLE || |
| c->std_error == EXEC_OUTPUT_SYSLOG || c->std_error == EXEC_OUTPUT_KMSG || c->std_error == EXEC_OUTPUT_JOURNAL || |
| c->std_error == EXEC_OUTPUT_SYSLOG_AND_CONSOLE || c->std_error == EXEC_OUTPUT_KMSG_AND_CONSOLE || c->std_error == EXEC_OUTPUT_JOURNAL_AND_CONSOLE) { |
| char *fac_str, *lvl_str; |
| int r; |
| |
| r = log_facility_unshifted_to_string_alloc(c->syslog_priority >> 3, &fac_str); |
| if (r < 0) |
| fac_str = NULL; |
| |
| r = log_level_to_string_alloc(LOG_PRI(c->syslog_priority), &lvl_str); |
| if (r < 0) |
| lvl_str = NULL; |
| |
| fprintf(f, |
| "%sSyslogFacility: %s\n" |
| "%sSyslogLevel: %s\n", |
| prefix, strna(fac_str), |
| prefix, strna(lvl_str)); |
| free(lvl_str); |
| free(fac_str); |
| } |
| |
| 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 & 1<<SECURE_KEEP_CAPS) ? " keep-caps" : "", |
| (c->secure_bits & 1<<SECURE_KEEP_CAPS_LOCKED) ? " keep-caps-locked" : "", |
| (c->secure_bits & 1<<SECURE_NO_SETUID_FIXUP) ? " no-setuid-fixup" : "", |
| (c->secure_bits & 1<<SECURE_NO_SETUID_FIXUP_LOCKED) ? " no-setuid-fixup-locked" : "", |
| (c->secure_bits & 1<<SECURE_NOROOT) ? " noroot" : "", |
| (c->secure_bits & 1<<SECURE_NOROOT_LOCKED) ? "noroot-locked" : ""); |
| |
| if (c->capability_bounding_set_drop) { |
| unsigned long l; |
| fprintf(f, "%sCapabilityBoundingSet:", prefix); |
| |
| for (l = 0; l <= cap_last_cap(); l++) |
| if (!(c->capability_bounding_set_drop & ((uint64_t) 1ULL << (uint64_t) l))) { |
| char *t; |
| |
| if ((t = cap_to_name(l))) { |
| fprintf(f, " %s", t); |
| cap_free(t); |
| } |
| } |
| |
| fputs("\n", f); |
| } |
| |
| if (c->user) |
| fprintf(f, "%sUser: %s\n", prefix, c->user); |
| if (c->group) |
| fprintf(f, "%sGroup: %s\n", prefix, c->group); |
| |
| if (strv_length(c->supplementary_groups) > 0) { |
| fprintf(f, "%sSupplementaryGroups:", prefix); |
| strv_fprintf(f, c->supplementary_groups); |
| fputs("\n", f); |
| } |
| |
| if (c->pam_name) |
| fprintf(f, "%sPAMName: %s\n", prefix, c->pam_name); |
| |
| 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); |
| } |
| |
| if (c->utmp_id) |
| fprintf(f, |
| "%sUtmpIdentifier: %s\n", |
| prefix, c->utmp_id); |
| } |
| |
| void exec_status_start(ExecStatus *s, pid_t pid) { |
| assert(s); |
| |
| zero(*s); |
| s->pid = pid; |
| dual_timestamp_get(&s->start_timestamp); |
| } |
| |
| void exec_status_exit(ExecStatus *s, ExecContext *context, pid_t pid, int code, int status) { |
| assert(s); |
| |
| if (s->pid && s->pid != pid) |
| zero(*s); |
| |
| s->pid = pid; |
| dual_timestamp_get(&s->exit_timestamp); |
| |
| s->code = code; |
| s->status = status; |
| |
| if (context) { |
| if (context->utmp_id) |
| utmp_put_dead_process(context->utmp_id, pid, code, status); |
| |
| exec_context_tty_reset(context); |
| } |
| } |
| |
| 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: %lu\n", |
| prefix, (unsigned long) s->pid); |
| |
| if (s->start_timestamp.realtime > 0) |
| fprintf(f, |
| "%sStart Timestamp: %s\n", |
| prefix, format_timestamp(buf, sizeof(buf), s->start_timestamp.realtime)); |
| |
| if (s->exit_timestamp.realtime > 0) |
| fprintf(f, |
| "%sExit Timestamp: %s\n" |
| "%sExit Code: %s\n" |
| "%sExit Status: %i\n", |
| prefix, format_timestamp(buf, sizeof(buf), s->exit_timestamp.realtime), |
| 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 kind of 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; |
| } |
| |
| 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" |
| }; |
| |
| DEFINE_STRING_TABLE_LOOKUP(exec_input, ExecInput); |
| |
| 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_SYSLOG_AND_CONSOLE] = "syslog+console", |
| [EXEC_OUTPUT_KMSG] = "kmsg", |
| [EXEC_OUTPUT_KMSG_AND_CONSOLE] = "kmsg+console", |
| [EXEC_OUTPUT_JOURNAL] = "journal", |
| [EXEC_OUTPUT_JOURNAL_AND_CONSOLE] = "journal+console", |
| [EXEC_OUTPUT_SOCKET] = "socket" |
| }; |
| |
| DEFINE_STRING_TABLE_LOOKUP(exec_output, ExecOutput); |