#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 <sys/stat.h>

#include <grp.h>

#include <poll.h>

#include <glob.h>

#include <utmpx.h>

#include <sys/personality.h>

#ifdef HAVE_PAM

#include <security/pam_appl.h>

#endif

#ifdef HAVE_SELINUX

#include <selinux/selinux.h>

#endif

#ifdef HAVE_SECCOMP

#include <seccomp.h>

#endif

#ifdef HAVE_APPARMOR

#include <sys/apparmor.h>

#endif

#include "sd-messages.h"

#include "rm-rf.h"

#include "strv.h"

#include "macro.h"

#include "capability.h"

#include "util.h"

#include "log.h"

#include "ioprio.h"

#include "securebits.h"

#include "namespace.h"

#include "exit-status.h"

#include "missing.h"

#include "utmp-wtmp.h"

#include "def.h"

#include "path-util.h"

#include "env-util.h"

#include "fileio.h"

#include "unit.h"

#include "async.h"

#include "selinux-util.h"

#include "errno-list.h"

#include "af-list.h"

#include "mkdir.h"

#include "smack-util.h"

#include "bus-endpoint.h"

#include "cap-list.h"

#include "formats-util.h"

#include "process-util.h"

#include "terminal-util.h"

#include "signal-util.h"

#ifdef HAVE_APPARMOR

#include "apparmor-util.h"

#endif

#ifdef HAVE_SECCOMP

#include "seccomp-util.h"

#endif

#include "execute.h"

#define IDLE_TIMEOUT_USEC (5*USEC_PER_SEC)

#define IDLE_TIMEOUT2_USEC (1*USEC_PER_SEC)

#define TTY_MODE 0620

#define SNDBUF_SIZE (8*1024*1024)

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;

nfd = fcntl(fds[i], F_DUPFD, i + 3);

if (nfd < 0)

return -errno;

safe_close(fds[i]);

fds[i] = nfd;

/* Hmm, the fd we wanted isn't free? Then

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++) {

r = fd_nonblock(fds[i], nonblock);

if (r < 0)

return r;

/* We unconditionally drop FD_CLOEXEC from the fds,

r = fd_cloexec(fds[i], false);

if (r < 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";

}

static 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;

}

static int open_null_as(int flags, int nfd) {

int fd, r;

assert(nfd >= 0);

fd = open("/dev/null", flags|O_NOCTTY);

if (fd < 0)

return -errno;

if (fd != nfd) {

r = dup2(fd, nfd) < 0 ? -errno : nfd;

safe_close(fd);

} else

r = nfd;

return r;

}

static int connect_journal_socket(int fd, uid_t uid, gid_t gid) {

union sockaddr_union sa = {

.un.sun_family = AF_UNIX,

.un.sun_path = "/run/systemd/journal/stdout",

};

uid_t olduid = UID_INVALID;

gid_t oldgid = GID_INVALID;

int r;

if (gid != GID_INVALID) {

oldgid = getgid();

r = setegid(gid);

if (r < 0)

return -errno;

}

if (uid != UID_INVALID) {

olduid = getuid();

r = seteuid(uid);

if (r < 0) {

r = -errno;

goto restore_gid;

}

}

r = connect(fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + strlen(sa.un.sun_path));

if (r < 0)

r = -errno;

/* If we fail to restore the uid or gid, things will likely

if (uid != UID_INVALID)

(void) seteuid(olduid);

restore_gid:

if (gid != GID_INVALID)

(void) setegid(oldgid);

return r;

}

static int connect_logger_as(const ExecContext *context, ExecOutput output, const char *ident, const char *unit_id, int nfd, uid_t uid, gid_t gid) {

int fd, r;

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_journal_socket(fd, uid, gid);

if (r < 0)

return r;

if (shutdown(fd, SHUT_RD) < 0) {

safe_close(fd);

return -errno;

}

fd_inc_sndbuf(fd, SNDBUF_SIZE);

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;

safe_close(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);

fd = open_terminal(path, mode | O_NOCTTY);

if (fd < 0)

return fd;

if (fd != nfd) {

r = dup2(fd, nfd) < 0 ? -errno : nfd;

safe_close(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;

fd = acquire_terminal(tty_path(context),

i == EXEC_INPUT_TTY_FAIL,

i == EXEC_INPUT_TTY_FORCE,

false,

USEC_INFINITY);

if (fd < 0)

return fd;

if (fd != STDIN_FILENO) {

r = dup2(fd, STDIN_FILENO) < 0 ? -errno : STDIN_FILENO;

safe_close(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(Unit *unit, const ExecContext *context, int fileno, int socket_fd, const char *ident, bool apply_tty_stdin, uid_t uid, gid_t gid) {

ExecOutput o;

ExecInput i;

int r;

assert(unit);

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

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, uid, gid);

if (r < 0) {

log_unit_error_errno(unit, r, "Failed to connect %s to the journal socket, ignoring: %m", fileno == STDOUT_FILENO ? "stdout" : "stderr");

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)

safe_close(fd);

*_saved_stdin = saved_stdin;

*_saved_stdout = saved_stdout;

return 0;

fail:

safe_close(saved_stdout);

safe_close(saved_stdin);

safe_close(fd);

return r;

}

_printf_(1, 2) static int write_confirm_message(const char *format, ...) {

_cleanup_close_ int fd = -1;

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);

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;

safe_close(*saved_stdin);

safe_close(*saved_stdout);

return r;

}

static int ask_for_confirmation(char *response, char **argv) {

int saved_stdout = -1, saved_stdin = -1, r;

_cleanup_free_ char *line = NULL;

r = setup_confirm_stdio(&saved_stdin, &saved_stdout);

if (r < 0)

return r;

line = exec_command_line(argv);

if (!line)

return -ENOMEM;

r = ask_char(response, "yns", "Execute %s? [Yes, No, Skip] ", 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

if (context->group || username) {

if (context->group) {

const char *g = context->group;

r = get_group_creds(&g, &gid);

if (r < 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) {

k = getgroups(ngroups_max, gids);

if (k < 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) {

assert(context);

/* Sets (but doesn't lookup) the uid and make sure we keep the

if (context->capabilities) {

_cleanup_cap_free_ cap_t d = NULL;

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

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

d = cap_dup(context->capabilities);

if (!d)

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)

return -errno;

if (cap_set_proc(d) < 0)

return -errno;

}

/* Third step: actually set the uids */

if (setresuid(uid, uid, uid) < 0)

return -errno;

/* At this point we should have all necessary capabilities but

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 old_ss;

int pam_code = PAM_SUCCESS;

int err;

char **e = NULL;

bool close_session = false;

pid_t pam_pid = 0, parent_pid;

int flags = 0;

assert(name);

assert(user);

assert(pam_env);

/* We set up PAM in the parent process, then fork. The child

if (log_get_max_level() < LOG_DEBUG)

flags |= PAM_SILENT;

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, flags);

if (pam_code != PAM_SUCCESS)

goto fail;

pam_code = pam_open_session(handle, flags);

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

assert_se(sigprocmask_many(SIG_BLOCK, &old_ss, SIGTERM, -1) >= 0);

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

/* This string must fit in 10 chars (i.e. the length

rename_process("(sd-pam)");

/* Make sure we don't keep open the passed fds in this

close_many(fds, n_fds);

/* Drop privileges - we don't need any to pam_close_session

if (setresuid(uid, uid, uid) < 0)

log_error_errno(r, "Error: Failed to setresuid() in sd-pam: %m");

(void) ignore_signals(SIGPIPE, -1);

/* Wait until our parent died. This will only work if

if (prctl(PR_SET_PDEATHSIG, SIGTERM) < 0)

goto child_finish;

/* Check if our parent process might already have

if (getppid() == parent_pid) {

sigset_t ss;

assert_se(sigemptyset(&ss) >= 0);

assert_se(sigaddset(&ss, SIGTERM) >= 0);

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, flags);

if (pam_code != PAM_SUCCESS)

goto child_finish;

}

r = 0;

child_finish:

pam_end(handle, pam_code | flags);

_exit(r);

}

/* If the child was forked off successfully it will do all the

handle = NULL;

/* Unblock SIGTERM again in the parent */

assert_se(sigprocmask(SIG_SETMASK, &old_ss, NULL) >= 0);

/* We close the log explicitly here, since the PAM modules

closelog();

*pam_env = e;

e = NULL;

return 0;

fail:

if (pam_code != PAM_SUCCESS) {

log_error("PAM failed: %s", pam_strerror(handle, pam_code));

err = -EPERM; /* PAM errors do not map to errno */

} else {

err = log_error_errno(errno, "PAM failed: %m");

}

if (handle) {

if (close_session)

pam_code = pam_close_session(handle, flags);

pam_end(handle, pam_code | flags);

}

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

p = basename(path);

if (isempty(p)) {

rename_process("(...)");

return;

}

l = strlen(p);

if (l > 8) {

/* The end of the process name is usually more

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);

}

#ifdef HAVE_SECCOMP

static int apply_seccomp(const ExecContext *c) {

uint32_t negative_action, action;

scmp_filter_ctx *seccomp;

Iterator i;

void *id;

int r;

assert(c);

negative_action = c->syscall_errno == 0 ? SCMP_ACT_KILL : SCMP_ACT_ERRNO(c->syscall_errno);

seccomp = seccomp_init(c->syscall_whitelist ? negative_action : SCMP_ACT_ALLOW);

if (!seccomp)

return -ENOMEM;

if (c->syscall_archs) {

SET_FOREACH(id, c->syscall_archs, i) {

r = seccomp_arch_add(seccomp, PTR_TO_UINT32(id) - 1);

if (r == -EEXIST)

continue;

if (r < 0)

goto finish;

}

} else {

r = seccomp_add_secondary_archs(seccomp);

if (r < 0)

goto finish;

}

action = c->syscall_whitelist ? SCMP_ACT_ALLOW : negative_action;

SET_FOREACH(id, c->syscall_filter, i) {

r = seccomp_rule_add(seccomp, action, PTR_TO_INT(id) - 1, 0);

if (r < 0)

goto finish;

}

r = seccomp_attr_set(seccomp, SCMP_FLTATR_CTL_NNP, 0);

if (r < 0)

goto finish;

r = seccomp_load(seccomp);

finish:

seccomp_release(seccomp);

return r;

}

static int apply_address_families(const ExecContext *c) {

scmp_filter_ctx *seccomp;

Iterator i;

int r;

assert(c);

seccomp = seccomp_init(SCMP_ACT_ALLOW);

if (!seccomp)

return -ENOMEM;

r = seccomp_add_secondary_archs(seccomp);

if (r < 0)

goto finish;

if (c->address_families_whitelist) {

int af, first = 0, last = 0;

void *afp;

/* If this is a whitelist, we first block the address

SET_FOREACH(afp, c->address_families, i) {

af = PTR_TO_INT(afp);

if (af <= 0 || af >= af_max())

continue;

if (first == 0 || af < first)

first = af;

if (last == 0 || af > last)

last = af;

}

assert((first == 0) == (last == 0));

if (first == 0) {

/* No entries in the valid range, block everything */

r = seccomp_rule_add(

seccomp,

SCMP_ACT_ERRNO(EPROTONOSUPPORT),

SCMP_SYS(socket),

0);

if (r < 0)

goto finish;

} else {

/* Block everything below the first entry */

r = seccomp_rule_add(

seccomp,

SCMP_ACT_ERRNO(EPROTONOSUPPORT),

SCMP_SYS(socket),

1,

SCMP_A0(SCMP_CMP_LT, first));

if (r < 0)

goto finish;

/* Block everything above the last entry */

r = seccomp_rule_add(

seccomp,

SCMP_ACT_ERRNO(EPROTONOSUPPORT),

SCMP_SYS(socket),

1,

SCMP_A0(SCMP_CMP_GT, last));

if (r < 0)

goto finish;

/* Block everything between the first and last

for (af = 1; af < af_max(); af++) {

if (set_contains(c->address_families, INT_TO_PTR(af)))

continue;

r = seccomp_rule_add(

seccomp,

SCMP_ACT_ERRNO(EPROTONOSUPPORT),

SCMP_SYS(socket),

1,

SCMP_A0(SCMP_CMP_EQ, af));

if (r < 0)

goto finish;

}

}

} else {

void *af;

/* If this is a blacklist, then generate one rule for

SET_FOREACH(af, c->address_families, i) {

r = seccomp_rule_add(

seccomp,

SCMP_ACT_ERRNO(EPROTONOSUPPORT),

SCMP_SYS(socket),

1,

SCMP_A0(SCMP_CMP_EQ, PTR_TO_INT(af)));

if (r < 0)

goto finish;

}

}

r = seccomp_attr_set(seccomp, SCMP_FLTATR_CTL_NNP, 0);

if (r < 0)

goto finish;

r = seccomp_load(seccomp);

finish:

seccomp_release(seccomp);

return r;

}

#endif

static void do_idle_pipe_dance(int idle_pipe[4]) {

assert(idle_pipe);

safe_close(idle_pipe[1]);

safe_close(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. */

r = write(idle_pipe[3], "x", 1);

if (r > 0)

/* Wait for systemd to react to the signal above. */

fd_wait_for_event(idle_pipe[0], POLLHUP, IDLE_TIMEOUT2_USEC);

}

safe_close(idle_pipe[0]);

}

safe_close(idle_pipe[3]);

}

static int build_environment(

const ExecContext *c,

unsigned n_fds,

usec_t watchdog_usec,

const char *home,

const char *username,

const char *shell,

char ***ret) {

_cleanup_strv_free_ char **our_env = NULL;

unsigned n_env = 0;

char *x;

assert(c);

assert(ret);

our_env = new0(char*, 10);

if (!our_env)

return -ENOMEM;

if (n_fds > 0) {

if (asprintf(&x, "LISTEN_PID="PID_FMT, getpid()) < 0)

return -ENOMEM;

our_env[n_env++] = x;

if (asprintf(&x, "LISTEN_FDS=%u", n_fds) < 0)

return -ENOMEM;

our_env[n_env++] = x;

}

if (watchdog_usec > 0) {

if (asprintf(&x, "WATCHDOG_PID="PID_FMT, getpid()) < 0)

return -ENOMEM;

our_env[n_env++] = x;

if (asprintf(&x, "WATCHDOG_USEC="USEC_FMT, watchdog_usec) < 0)

return -ENOMEM;

our_env[n_env++] = x;

}

if (home) {

x = strappend("HOME=", home);

if (!x)

return -ENOMEM;

our_env[n_env++] = x;

}

if (username) {

x = strappend("LOGNAME=", username);

if (!x)

return -ENOMEM;

our_env[n_env++] = x;

x = strappend("USER=", username);

if (!x)

return -ENOMEM;

our_env[n_env++] = x;

}

if (shell) {

x = strappend("SHELL=", shell);

if (!x)

return -ENOMEM;

our_env[n_env++] = x;

}

if (is_terminal_input(c->std_input) ||

c->std_output == EXEC_OUTPUT_TTY ||

c->std_error == EXEC_OUTPUT_TTY ||

c->tty_path) {

x = strdup(default_term_for_tty(tty_path(c)));

if (!x)

return -ENOMEM;

our_env[n_env++] = x;

}

our_env[n_env++] = NULL;

assert(n_env <= 10);

*ret = our_env;

our_env = NULL;

return 0;

}

static bool exec_needs_mount_namespace(

const ExecContext *context,

const ExecParameters *params,

ExecRuntime *runtime) {

assert(context);

assert(params);

if (!strv_isempty(context->read_write_dirs) ||

!strv_isempty(context->read_only_dirs) ||

!strv_isempty(context->inaccessible_dirs))

return true;

if (context->mount_flags != 0)

return true;

if (context->private_tmp && runtime && (runtime->tmp_dir || runtime->var_tmp_dir))

return true;

if (params->bus_endpoint_path)

return true;

if (context->private_devices ||

context->protect_system != PROTECT_SYSTEM_NO ||

context->protect_home != PROTECT_HOME_NO)

return true;

return false;

}

static int exec_child(

Unit *unit,

ExecCommand *command,

const ExecContext *context,

const ExecParameters *params,

ExecRuntime *runtime,

char **argv,

int socket_fd,

int *fds, unsigned n_fds,

char **files_env,

int *exit_status) {

_cleanup_strv_free_ char **our_env = NULL, **pam_env = NULL, **final_env = NULL, **final_argv = NULL;

_cleanup_free_ char *mac_selinux_context_net = NULL;

const char *username = NULL, *home = NULL, *shell = NULL;

unsigned n_dont_close = 0;

int dont_close[n_fds + 4];

uid_t uid = UID_INVALID;

gid_t gid = GID_INVALID;

int i, r;

bool needs_mount_namespace;

assert(unit);

assert(command);

assert(context);

assert(params);

assert(exit_status);

rename_process_from_path(command->path);

/* We reset exactly these signals, since they are the

(void) default_signals(SIGNALS_CRASH_HANDLER,

SIGNALS_IGNORE, -1);

if (context->ignore_sigpipe)

(void) ignore_signals(SIGPIPE, -1);

r = reset_signal_mask();

if (r < 0) {

*exit_status = EXIT_SIGNAL_MASK;

return r;

}

if (params->idle_pipe)

do_idle_pipe_dance(params->idle_pipe);

/* Close sockets very early to make sure we don't

log_forget_fds();

if (socket_fd >= 0)

dont_close[n_dont_close++] = socket_fd;

if (n_fds > 0) {

memcpy(dont_close + n_dont_close, fds, sizeof(int) * n_fds);

n_dont_close += n_fds;

}

if (params->bus_endpoint_fd >= 0)

dont_close[n_dont_close++] = params->bus_endpoint_fd;

if (runtime) {

if (runtime->netns_storage_socket[0] >= 0)

dont_close[n_dont_close++] = runtime->netns_storage_socket[0];

if (runtime->netns_storage_socket[1] >= 0)

dont_close[n_dont_close++] = runtime->netns_storage_socket[1];

}

r = close_all_fds(dont_close, n_dont_close);

if (r < 0) {

*exit_status = EXIT_FDS;

return r;

}

if (!context->same_pgrp)

if (setsid() < 0) {

*exit_status = EXIT_SETSID;

return -errno;

}

exec_context_tty_reset(context);

if (params->confirm_spawn) {

char response;

r = ask_for_confirmation(&response, argv);

if (r == -ETIMEDOUT)

write_confirm_message("Confirmation question timed out, assuming positive response.\n");

else if (r < 0)

write_confirm_message("Couldn't ask confirmation question, assuming positive response: %s\n", strerror(-r));

else if (response == 's') {

write_confirm_message("Skipping execution.\n");

*exit_status = EXIT_CONFIRM;

return -ECANCELED;

} else if (response == 'n') {

write_confirm_message("Failing execution.\n");

*exit_status = 0;

return 0;

}

}

if (context->user) {

username = context->user;

r = get_user_creds(&username, &uid, &gid, &home, &shell);

if (r < 0) {

*exit_status = EXIT_USER;

return r;

}

}

/* If a socket is connected to STDIN/STDOUT/STDERR, we

if (socket_fd >= 0)

fd_nonblock(socket_fd, false);

r = setup_input(context, socket_fd, params->apply_tty_stdin);

if (r < 0) {

*exit_status = EXIT_STDIN;

return r;

}

r = setup_output(unit, context, STDOUT_FILENO, socket_fd, basename(command->path), params->apply_tty_stdin, uid, gid);

if (r < 0) {

*exit_status = EXIT_STDOUT;

return r;

}

r = setup_output(unit, context, STDERR_FILENO, socket_fd, basename(command->path), params->apply_tty_stdin, uid, gid);

if (r < 0) {

*exit_status = EXIT_STDERR;

return r;

}

if (params->cgroup_path) {

r = cg_attach_everywhere(params->cgroup_supported, params->cgroup_path, 0, NULL, NULL);

if (r < 0) {

*exit_status = EXIT_CGROUP;

return r;

}

}

if (context->oom_score_adjust_set) {

char t[DECIMAL_STR_MAX(context->oom_score_adjust)];

/* When we can't make this change due to EPERM, then

sprintf(t, "%i", context->oom_score_adjust);

r = write_string_file("/proc/self/oom_score_adj", t, 0);

if (r == -EPERM || r == -EACCES) {

log_open();

log_unit_debug_errno(unit, r, "Failed to adjust OOM setting, assuming containerized execution, ignoring: %m");

log_close();

} else if (r < 0) {

*exit_status = EXIT_OOM_ADJUST;

return -errno;

}

}

if (context->nice_set)

if (setpriority(PRIO_PROCESS, 0, context->nice) < 0) {

*exit_status = EXIT_NICE;

return -errno;

}

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),

&param);

if (r < 0) {

*exit_status = EXIT_SETSCHEDULER;

return -errno;

}

}

if (context->cpuset)

if (sched_setaffinity(0, CPU_ALLOC_SIZE(context->cpuset_ncpus), context->cpuset) < 0) {

*exit_status = EXIT_CPUAFFINITY;

return -errno;

}

if (context->ioprio_set)

if (ioprio_set(IOPRIO_WHO_PROCESS, 0, context->ioprio) < 0) {

*exit_status = EXIT_IOPRIO;

return -errno;

}

if (context->timer_slack_nsec != NSEC_INFINITY)

if (prctl(PR_SET_TIMERSLACK, context->timer_slack_nsec) < 0) {

*exit_status = EXIT_TIMERSLACK;

return -errno;

}

if (context->personality != PERSONALITY_INVALID)

if (personality(context->personality) < 0) {

*exit_status = EXIT_PERSONALITY;

return -errno;

}

if (context->utmp_id)

utmp_put_init_process(context->utmp_id, getpid(), getsid(0), context->tty_path,

context->utmp_mode == EXEC_UTMP_INIT ? INIT_PROCESS :

context->utmp_mode == EXEC_UTMP_LOGIN ? LOGIN_PROCESS :

USER_PROCESS,

username ? "root" : context->user);

if (context->user && is_terminal_input(context->std_input)) {

r = chown_terminal(STDIN_FILENO, uid);

if (r < 0) {

*exit_status = EXIT_STDIN;

return r;

}

}

if (params->bus_endpoint_fd >= 0 && context->bus_endpoint) {

uid_t ep_uid = (uid == UID_INVALID) ? 0 : uid;

r = bus_kernel_set_endpoint_policy(params->bus_endpoint_fd, ep_uid, context->bus_endpoint);

if (r < 0) {

*exit_status = EXIT_BUS_ENDPOINT;

return r;

}

}

/* If delegation is enabled we'll pass ownership of the cgroup

if (params->cgroup_path && context->user && params->cgroup_delegate) {

r = cg_set_task_access(SYSTEMD_CGROUP_CONTROLLER, params->cgroup_path, 0644, uid, gid);

if (r < 0) {

*exit_status = EXIT_CGROUP;

return r;

}

r = cg_set_group_access(SYSTEMD_CGROUP_CONTROLLER, params->cgroup_path, 0755, uid, gid);

if (r < 0) {

*exit_status = EXIT_CGROUP;

return r;

}

}

if (!strv_isempty(context->runtime_directory) && params->runtime_prefix) {

char **rt;

STRV_FOREACH(rt, context->runtime_directory) {

_cleanup_free_ char *p;

p = strjoin(params->runtime_prefix, "/", *rt, NULL);

if (!p) {

*exit_status = EXIT_RUNTIME_DIRECTORY;

return -ENOMEM;

}

r = mkdir_p_label(p, context->runtime_directory_mode);

if (r < 0) {

*exit_status = EXIT_RUNTIME_DIRECTORY;

return r;

}

r = chmod_and_chown(p, context->runtime_directory_mode, uid, gid);

if (r < 0) {

*exit_status = EXIT_RUNTIME_DIRECTORY;

return r;

}

}

}

if (params->apply_permissions) {

r = enforce_groups(context, username, gid);

if (r < 0) {

*exit_status = EXIT_GROUP;

return r;

}

}

umask(context->umask);

#ifdef HAVE_PAM

if (params->apply_permissions && context->pam_name && username) {

r = setup_pam(context->pam_name, username, uid, context->tty_path, &pam_env, fds, n_fds);

if (r < 0) {

*exit_status = EXIT_PAM;

return r;

}

}

#endif

if (context->private_network && runtime && runtime->netns_storage_socket[0] >= 0) {

r = setup_netns(runtime->netns_storage_socket);

if (r < 0) {

*exit_status = EXIT_NETWORK;

return r;

}

}

needs_mount_namespace = exec_needs_mount_namespace(context, params, runtime);

if (needs_mount_namespace) {

char *tmp = NULL, *var = NULL;

/* The runtime struct only contains the parent

if (context->private_tmp && runtime) {

if (runtime->tmp_dir)

tmp = strjoina(runtime->tmp_dir, "/tmp");

if (runtime->var_tmp_dir)

var = strjoina(runtime->var_tmp_dir, "/tmp");

}

r = setup_namespace(

params->apply_chroot ? context->root_directory : NULL,

context->read_write_dirs,

context->read_only_dirs,

context->inaccessible_dirs,

tmp,

var,

params->bus_endpoint_path,

context->private_devices,

context->protect_home,

context->protect_system,

context->mount_flags);

/* If we couldn't set up the namespace this is

if (r == -EPERM || r == -EACCES) {

log_open();

log_unit_debug_errno(unit, r, "Failed to set up namespace, assuming containerized execution, ignoring: %m");

log_close();

} else if (r < 0) {

*exit_status = EXIT_NAMESPACE;

return r;

}

}

if (params->apply_chroot) {

if (!needs_mount_namespace && context->root_directory)

if (chroot(context->root_directory) < 0) {

*exit_status = EXIT_CHROOT;

return -errno;

}

if (chdir(context->working_directory ?: "/") < 0 &&

!context->working_directory_missing_ok) {

*exit_status = EXIT_CHDIR;

return -errno;

}

} else {

_cleanup_free_ char *d = NULL;

if (asprintf(&d, "%s/%s",

context->root_directory ?: "",

context->working_directory ?: "") < 0) {

*exit_status = EXIT_MEMORY;

return -ENOMEM;

}

if (chdir(d) < 0 &&

!context->working_directory_missing_ok) {

*exit_status = EXIT_CHDIR;

return -errno;

}

}

#ifdef HAVE_SELINUX

if (params->apply_permissions && mac_selinux_use() && params->selinux_context_net && socket_fd >= 0) {

r = mac_selinux_get_child_mls_label(socket_fd, command->path, context->selinux_context, &mac_selinux_context_net);

if (r < 0) {

*exit_status = EXIT_SELINUX_CONTEXT;

return r;

}

}

#endif

/* We repeat the fd closing here, to make sure that

r = close_all_fds(fds, n_fds);

if (r >= 0)

r = shift_fds(fds, n_fds);

if (r >= 0)

r = flags_fds(fds, n_fds, context->non_blocking);

if (r < 0) {

*exit_status = EXIT_FDS;

return r;

}

if (params->apply_permissions) {

for (i = 0; i < _RLIMIT_MAX; i++) {

if (!context->rlimit[i])

continue;

if (setrlimit_closest(i, context->rlimit[i]) < 0) {

*exit_status = EXIT_LIMITS;

return -errno;

}

}

if (context->capability_bounding_set_drop) {

r = capability_bounding_set_drop(context->capability_bounding_set_drop, false);

if (r < 0) {

*exit_status = EXIT_CAPABILITIES;

return r;

}

}

#ifdef HAVE_SMACK

if (context->smack_process_label) {

r = mac_smack_apply_pid(0, context->smack_process_label);

if (r < 0) {

*exit_status = EXIT_SMACK_PROCESS_LABEL;

return r;

}

}

#ifdef SMACK_DEFAULT_PROCESS_LABEL

else {

_cleanup_free_ char *exec_label = NULL;

r = mac_smack_read(command->path, SMACK_ATTR_EXEC, &exec_label);

if (r < 0 && r != -ENODATA && r != -EOPNOTSUPP) {

*exit_status = EXIT_SMACK_PROCESS_LABEL;

return r;

}

r = mac_smack_apply_pid(0, exec_label ? : SMACK_DEFAULT_PROCESS_LABEL);

if (r < 0) {

*exit_status = EXIT_SMACK_PROCESS_LABEL;

return r;

}

}

#endif

#endif

if (context->user) {

r = enforce_user(context, uid);

if (r < 0) {

*exit_status = EXIT_USER;

return r;

}

}

/* PR_GET_SECUREBITS is not privileged, while

if (prctl(PR_GET_SECUREBITS) != context->secure_bits)

if (prctl(PR_SET_SECUREBITS, context->secure_bits) < 0) {

*exit_status = EXIT_SECUREBITS;

return -errno;

}

if (context->capabilities)

if (cap_set_proc(context->capabilities) < 0) {

*exit_status = EXIT_CAPABILITIES;

return -errno;

}

if (context->no_new_privileges)

if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0) < 0) {

*exit_status = EXIT_NO_NEW_PRIVILEGES;

return -errno;

}

#ifdef HAVE_SECCOMP

if (context->address_families_whitelist ||

!set_isempty(context->address_families)) {

r = apply_address_families(context);

if (r < 0) {

*exit_status = EXIT_ADDRESS_FAMILIES;

return r;

}

}

if (context->syscall_whitelist ||

!set_isempty(context->syscall_filter) ||

!set_isempty(context->syscall_archs)) {

r = apply_seccomp(context);

if (r < 0) {

*exit_status = EXIT_SECCOMP;

return r;

}

}

#endif

#ifdef HAVE_SELINUX

if (mac_selinux_use()) {

char *exec_context = mac_selinux_context_net ?: context->selinux_context;

if (exec_context) {

r = setexeccon(exec_context);

if (r < 0) {

*exit_status = EXIT_SELINUX_CONTEXT;

return r;

}

}

}

#endif

#ifdef HAVE_APPARMOR

if (context->apparmor_profile && mac_apparmor_use()) {

r = aa_change_onexec(context->apparmor_profile);

if (r < 0 && !context->apparmor_profile_ignore) {

*exit_status = EXIT_APPARMOR_PROFILE;

return -errno;

}

}

#endif

}

r = build_environment(context, n_fds, params->watchdog_usec, home, username, shell, &our_env);

if (r < 0) {

*exit_status = EXIT_MEMORY;

return r;

}

final_env = strv_env_merge(5,

params->environment,

our_env,

context->environment,

files_env,

pam_env,

NULL);

if (!final_env) {

*exit_status = EXIT_MEMORY;

return -ENOMEM;

}

final_argv = replace_env_argv(argv, final_env);

if (!final_argv) {

*exit_status = EXIT_MEMORY;

return -ENOMEM;

}

final_env = strv_env_clean(final_env);

if (_unlikely_(log_get_max_level() >= LOG_DEBUG)) {

_cleanup_free_ char *line;

line = exec_command_line(final_argv);

if (line) {

log_open();

log_struct(LOG_DEBUG,

LOG_UNIT_ID(unit),

"EXECUTABLE=%s", command->path,

LOG_UNIT_MESSAGE(unit, "Executing: %s", line),

NULL);

log_close();

}

}

execve(command->path, final_argv, final_env);

*exit_status = EXIT_EXEC;

return -errno;

}

int exec_spawn(Unit *unit,

ExecCommand *command,

const ExecContext *context,

const ExecParameters *params,

ExecRuntime *runtime,

pid_t *ret) {

_cleanup_strv_free_ char **files_env = NULL;

int *fds = NULL; unsigned n_fds = 0;

_cleanup_free_ char *line = NULL;

int socket_fd, r;

char **argv;

pid_t pid;

assert(unit);

assert(command);

assert(context);

assert(ret);

assert(params);

assert(params->fds || params->n_fds <= 0);

if (context->std_input == EXEC_INPUT_SOCKET ||

context->std_output == EXEC_OUTPUT_SOCKET ||

context->std_error == EXEC_OUTPUT_SOCKET) {

if (params->n_fds != 1) {

log_unit_error(unit, "Got more than one socket.");

return -EINVAL;

}

socket_fd = params->fds[0];

} else {

socket_fd = -1;

fds = params->fds;

n_fds = params->n_fds;

}

r = exec_context_load_environment(unit, context, &files_env);

if (r < 0)

return log_unit_error_errno(unit, r, "Failed to load environment files: %m");

argv = params->argv ?: command->argv;

line = exec_command_line(argv);

if (!line)

return log_oom();

log_struct(LOG_DEBUG,

LOG_UNIT_ID(unit),

LOG_UNIT_MESSAGE(unit, "About to execute: %s", line),

"EXECUTABLE=%s", command->path,

NULL);

pid = fork();

if (pid < 0)

return log_unit_error_errno(unit, r, "Failed to fork: %m");

if (pid == 0) {

int exit_status;

r = exec_child(unit,

command,

context,

params,

runtime,

argv,

socket_fd,

fds, n_fds,

files_env,

&exit_status);

if (r < 0) {

log_open();

log_struct_errno(LOG_ERR, r,

LOG_MESSAGE_ID(SD_MESSAGE_SPAWN_FAILED),

LOG_UNIT_ID(unit),

LOG_UNIT_MESSAGE(unit, "Failed at step %s spawning %s: %m",

exit_status_to_string(exit_status, EXIT_STATUS_SYSTEMD),

command->path),

"EXECUTABLE=%s", command->path,

NULL);

}

_exit(exit_status);

}

log_unit_debug(unit, "Forked %s as "PID_FMT, command->path, pid);

/* We add the new process to the cgroup both in the child (so

if (params->cgroup_path)

(void) cg_attach(SYSTEMD_CGROUP_CONTROLLER, params->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_INFINITY;

c->personality = PERSONALITY_INVALID;

c->runtime_directory_mode = 0755;

}

void exec_context_done(ExecContext *c) {

unsigned l;

assert(c);

c->environment = strv_free(c->environment);

c->environment_files = strv_free(c->environment_files);

for (l = 0; l < ELEMENTSOF(c->rlimit); l++)

c->rlimit[l] = mfree(c->rlimit[l]);

c->working_directory = mfree(c->working_directory);

c->root_directory = mfree(c->root_directory);

c->tty_path = mfree(c->tty_path);

c->syslog_identifier = mfree(c->syslog_identifier);

c->user = mfree(c->user);

c->group = mfree(c->group);

c->supplementary_groups = strv_free(c->supplementary_groups);

c->pam_name = mfree(c->pam_name);

if (c->capabilities) {

cap_free(c->capabilities);

c->capabilities = NULL;

}

c->read_only_dirs = strv_free(c->read_only_dirs);

c->read_write_dirs = strv_free(c->read_write_dirs);

c->inaccessible_dirs = strv_free(c->inaccessible_dirs);

if (c->cpuset)

CPU_FREE(c->cpuset);

c->utmp_id = mfree(c->utmp_id);

c->selinux_context = mfree(c->selinux_context);

c->apparmor_profile = mfree(c->apparmor_profile);

set_free(c->syscall_filter);

c->syscall_filter = NULL;

set_free(c->syscall_archs);

c->syscall_archs = NULL;

set_free(c->address_families);

c->address_families = NULL;

c->runtime_directory = strv_free(c->runtime_directory);

bus_endpoint_free(c->bus_endpoint);

c->bus_endpoint = NULL;

}

int exec_context_destroy_runtime_directory(ExecContext *c, const char *runtime_prefix) {

char **i;

assert(c);

if (!runtime_prefix)

return 0;

STRV_FOREACH(i, c->runtime_directory) {

_cleanup_free_ char *p;

p = strjoin(runtime_prefix, "/", *i, NULL);

if (!p)

return -ENOMEM;

/* We execute this synchronously, since we need to be

(void) rm_rf(p, REMOVE_ROOT);

}

return 0;

}

void exec_command_done(ExecCommand *c) {

assert(c);

c->path = mfree(c->path);

c->argv = strv_free(c->argv);

}

void exec_command_done_array(ExecCommand *c, unsigned n) {

unsigned i;

for (i = 0; i < n; i++)

exec_command_done(c+i);

}

ExecCommand* exec_command_free_list(ExecCommand *c) {

ExecCommand *i;

while ((i = c)) {

LIST_REMOVE(command, c, i);

exec_command_done(i);

free(i);

}

return NULL;

}

void exec_command_free_array(ExecCommand **c, unsigned n) {

unsigned i;

for (i = 0; i < n; i++)

c[i] = exec_command_free_list(c[i]);

}

typedef struct InvalidEnvInfo {

Unit *unit;

const char *path;

} InvalidEnvInfo;

static void invalid_env(const char *p, void *userdata) {

InvalidEnvInfo *info = userdata;

log_unit_error(info->unit, "Ignoring invalid environment assignment '%s': %s", p, info->path);

}

int exec_context_load_environment(Unit *unit, 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(NULL, 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) {

InvalidEnvInfo info = {

.unit = unit,

.path = pglob.gl_pathv[n]

};

p = strv_env_clean_with_callback(p, invalid_env, &info);

}

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) {

_cleanup_free_ char *active = NULL;

char *console;

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 */

return streq(console, tty) || (streq(console, "tty0") && tty_is_vc(tty));

}

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"

"%sPrivateDevices: %s\n"

"%sProtectHome: %s\n"

"%sProtectSystem: %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->private_devices),

prefix, protect_home_to_string(c->protect_home),

prefix, protect_system_to_string(c->protect_system),

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->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: "RLIM_FMT"\n",

prefix, rlimit_to_string(i), c->rlimit[i]->rlim_max);

if (c->ioprio_set) {

_cleanup_free_ char *class_str = NULL;

ioprio_class_to_string_alloc(IOPRIO_PRIO_CLASS(c->ioprio), &class_str);

fprintf(f,

"%sIOSchedulingClass: %s\n"

"%sIOPriority: %i\n",

prefix, strna(class_str),

prefix, (int) IOPRIO_PRIO_DATA(c->ioprio));

}

if (c->cpu_sched_set) {

_cleanup_free_ char *policy_str = NULL;

sched_policy_to_string_alloc(c->cpu_sched_policy, &policy_str);

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));

}

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, " %u", i);

fputs("\n", f);

}

if (c->timer_slack_nsec != NSEC_INFINITY)

fprintf(f, "%sTimerSlackNSec: "NSEC_FMT "\n", prefix, 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) {

_cleanup_free_ char *fac_str = NULL, *lvl_str = NULL;

log_facility_unshifted_to_string_alloc(c->syslog_priority >> 3, &fac_str);

log_level_to_string_alloc(LOG_PRI(c->syslog_priority), &lvl_str);

fprintf(f,

"%sSyslogFacility: %s\n"

"%sSyslogLevel: %s\n",

prefix, strna(fac_str),

prefix, strna(lvl_str));

}

if (c->capabilities) {

_cleanup_cap_free_charp_ char *t;

t = cap_to_text(c->capabilities, NULL);

if (t)

fprintf(f, "%sCapabilities: %s\n", prefix, 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)))

fprintf(f, " %s", strna(capability_to_name(l)));

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);

if (c->selinux_context)

fprintf(f,

"%sSELinuxContext: %s%s\n",

prefix, c->selinux_context_ignore ? "-" : "", c->selinux_context);

if (c->personality != PERSONALITY_INVALID)

fprintf(f,

"%sPersonality: %s\n",

prefix, strna(personality_to_string(c->personality)));

if (c->syscall_filter) {

#ifdef HAVE_SECCOMP

Iterator j;

void *id;

bool first = true;

#endif

fprintf(f,

"%sSystemCallFilter: ",

prefix);

if (!c->syscall_whitelist)

fputc('~', f);

#ifdef HAVE_SECCOMP

SET_FOREACH(id, c->syscall_filter, j) {

_cleanup_free_ char *name = NULL;

if (first)

first = false;

else

fputc(' ', f);

name = seccomp_syscall_resolve_num_arch(SCMP_ARCH_NATIVE, PTR_TO_INT(id) - 1);

fputs(strna(name), f);

}

#endif

fputc('\n', f);

}

if (c->syscall_archs) {

#ifdef HAVE_SECCOMP

Iterator j;

void *id;

#endif

fprintf(f,

"%sSystemCallArchitectures:",

prefix);

#ifdef HAVE_SECCOMP

SET_FOREACH(id, c->syscall_archs, j)

fprintf(f, " %s", strna(seccomp_arch_to_string(PTR_TO_UINT32(id) - 1)));

#endif

fputc('\n', f);

}

if (c->syscall_errno != 0)

fprintf(f,

"%sSystemCallErrorNumber: %s\n",

prefix, strna(errno_to_name(c->syscall_errno)));

if (c->apparmor_profile)

fprintf(f,

"%sAppArmorProfile: %s%s\n",

prefix, c->apparmor_profile_ignore ? "-" : "", c->apparmor_profile);

}

bool exec_context_maintains_privileges(ExecContext *c) {

assert(c);

/* Returns true if the process forked off would run run under

if (!c->user)

return true;

if (streq(c->user, "root") || streq(c->user, "0"))

return true;

return false;

}

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 (s->pid <= 0)

return;

prefix = strempty(prefix);

fprintf(f,

"%sPID: "PID_FMT"\n",

prefix, 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

return n;

}

void exec_command_dump(ExecCommand *c, FILE *f, const char *prefix) {

_cleanup_free_ char *cmd = NULL;

const char *prefix2;

assert(c);

assert(f);

prefix = strempty(prefix);

prefix2 = strjoina(prefix, "\t");

cmd = exec_command_line(c->argv);

fprintf(f,

"%sCommand Line: %s\n",

prefix, cmd ? cmd : strerror(ENOMEM));

exec_status_dump(&c->exec_status, f, prefix2);

}

void exec_command_dump_list(ExecCommand *c, FILE *f, const char *prefix) {

assert(f);

prefix = strempty(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(command, *l, end);

LIST_INSERT_AFTER(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;

p = strdup(path);

if (!p) {

strv_free(l);

return -ENOMEM;

}

free(c->path);

c->path = p;

strv_free(c->argv);

c->argv = l;

return 0;

}

int exec_command_append(ExecCommand *c, const char *path, ...) {

_cleanup_strv_free_ char **l = NULL;

va_list ap;

int r;

assert(c);

assert(path);

va_start(ap, path);

l = strv_new_ap(path, ap);

va_end(ap);

if (!l)

return -ENOMEM;

r = strv_extend_strv(&c->argv, l);

if (r < 0)

return r;

return 0;

}

static int exec_runtime_allocate(ExecRuntime **rt) {

if (*rt)

return 0;

*rt = new0(ExecRuntime, 1);

if (!*rt)

return -ENOMEM;

(*rt)->n_ref = 1;

(*rt)->netns_storage_socket[0] = (*rt)->netns_storage_socket[1] = -1;

return 0;

}

int exec_runtime_make(ExecRuntime **rt, ExecContext *c, const char *id) {

int r;

assert(rt);

assert(c);

assert(id);

if (*rt)

return 1;

if (!c->private_network && !c->private_tmp)

return 0;

r = exec_runtime_allocate(rt);

if (r < 0)

return r;

if (c->private_network && (*rt)->netns_storage_socket[0] < 0) {

if (socketpair(AF_UNIX, SOCK_DGRAM, 0, (*rt)->netns_storage_socket) < 0)

return -errno;

}

if (c->private_tmp && !(*rt)->tmp_dir) {

r = setup_tmp_dirs(id, &(*rt)->tmp_dir, &(*rt)->var_tmp_dir);

if (r < 0)

return r;

}

return 1;

}

ExecRuntime *exec_runtime_ref(ExecRuntime *r) {

assert(r);

assert(r->n_ref > 0);

r->n_ref++;

return r;

}

ExecRuntime *exec_runtime_unref(ExecRuntime *r) {

if (!r)

return NULL;

assert(r->n_ref > 0);

r->n_ref--;

if (r->n_ref > 0)

return NULL;

free(r->tmp_dir);

free(r->var_tmp_dir);

safe_close_pair(r->netns_storage_socket);

free(r);

return NULL;

}

int exec_runtime_serialize(Unit *u, ExecRuntime *rt, FILE *f, FDSet *fds) {

assert(u);

assert(f);

assert(fds);

if (!rt)

return 0;

if (rt->tmp_dir)

unit_serialize_item(u, f, "tmp-dir", rt->tmp_dir);

if (rt->var_tmp_dir)

unit_serialize_item(u, f, "var-tmp-dir", rt->var_tmp_dir);

if (rt->netns_storage_socket[0] >= 0) {

int copy;

copy = fdset_put_dup(fds, rt->netns_storage_socket[0]);

if (copy < 0)

return copy;

unit_serialize_item_format(u, f, "netns-socket-0", "%i", copy);

}

if (rt->netns_storage_socket[1] >= 0) {

int copy;

copy = fdset_put_dup(fds, rt->netns_storage_socket[1]);

if (copy < 0)

return copy;

unit_serialize_item_format(u, f, "netns-socket-1", "%i", copy);

}

return 0;

}

int exec_runtime_deserialize_item(Unit *u, ExecRuntime **rt, const char *key, const char *value, FDSet *fds) {

int r;

assert(rt);

assert(key);

assert(value);

if (streq(key, "tmp-dir")) {

char *copy;

r = exec_runtime_allocate(rt);

if (r < 0)

return log_oom();

copy = strdup(value);

if (!copy)

return log_oom();

free((*rt)->tmp_dir);

(*rt)->tmp_dir = copy;

} else if (streq(key, "var-tmp-dir")) {

char *copy;

r = exec_runtime_allocate(rt);

if (r < 0)

return log_oom();

copy = strdup(value);

if (!copy)

return log_oom();

free((*rt)->var_tmp_dir);

(*rt)->var_tmp_dir = copy;

} else if (streq(key, "netns-socket-0")) {

int fd;

r = exec_runtime_allocate(rt);

if (r < 0)

return log_oom();

if (safe_atoi(value, &fd) < 0 || !fdset_contains(fds, fd))

log_unit_debug(u, "Failed to parse netns socket value: %s", value);

else {

safe_close((*rt)->netns_storage_socket[0]);

(*rt)->netns_storage_socket[0] = fdset_remove(fds, fd);

}

} else if (streq(key, "netns-socket-1")) {

int fd;

r = exec_runtime_allocate(rt);

if (r < 0)

return log_oom();

if (safe_atoi(value, &fd) < 0 || !fdset_contains(fds, fd))

log_unit_debug(u, "Failed to parse netns socket value: %s", value);

else {

safe_close((*rt)->netns_storage_socket[1]);

(*rt)->netns_storage_socket[1] = fdset_remove(fds, fd);

}

} else

return 0;

return 1;

}

static void *remove_tmpdir_thread(void *p) {

_cleanup_free_ char *path = p;

(void) rm_rf(path, REMOVE_ROOT|REMOVE_PHYSICAL);

return NULL;

}

void exec_runtime_destroy(ExecRuntime *rt) {

int r;

if (!rt)

return;

/* If there are multiple users of this, let's leave the stuff around */

if (rt->n_ref > 1)

return;

if (rt->tmp_dir) {

log_debug("Spawning thread to nuke %s", rt->tmp_dir);

r = asynchronous_job(remove_tmpdir_thread, rt->tmp_dir);

if (r < 0) {

log_warning_errno(r, "Failed to nuke %s: %m", rt->tmp_dir);

free(rt->tmp_dir);

}

rt->tmp_dir = NULL;

}

if (rt->var_tmp_dir) {

log_debug("Spawning thread to nuke %s", rt->var_tmp_dir);

r = asynchronous_job(remove_tmpdir_thread, rt->var_tmp_dir);

if (r < 0) {

log_warning_errno(r, "Failed to nuke %s: %m", rt->var_tmp_dir);

free(rt->var_tmp_dir);

}

rt->var_tmp_dir = NULL;

}

safe_close_pair(rt->netns_storage_socket);

}

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);

static const char* const exec_utmp_mode_table[_EXEC_UTMP_MODE_MAX] = {

[EXEC_UTMP_INIT] = "init",

[EXEC_UTMP_LOGIN] = "login",

[EXEC_UTMP_USER] = "user",

};

DEFINE_STRING_TABLE_LOOKUP(exec_utmp_mode, ExecUtmpMode);