core: turn various execution flags into a proper flags parameter

The ExecParameters structure contains a number of bit-flags, that were so far
exposed as bool:1, change this to a proper, single binary bit flag field. This
makes things a bit more expressive, and is helpful as we add more flags, since
these booleans are passed around in various callers, for example
service_spawn(), whose signature can be made much shorter now.

Not all bit booleans from ExecParameters are moved into the flags field for
now, but this can be added later.

6 files changed, 72 insertions, 92 deletions

diff --git a/src/core/execute.c b/src/core/execute.c
index 77a75245cb..bc0fd27402 100644
--- a/src/core/execute.c
+++ b/src/core/execute.c
@@ -427,7 +427,7 @@ static int setup_input(
                 return STDIN_FILENO;
         }
 
-        i = fixup_input(context->std_input, socket_fd, params->apply_tty_stdin);
+        i = fixup_input(context->std_input, socket_fd, params->flags & EXEC_APPLY_TTY_STDIN);
 
         switch (i) {
 
@@ -502,7 +502,7 @@ static int setup_output(
                 return STDERR_FILENO;
         }
 
-        i = fixup_input(context->std_input, socket_fd, params->apply_tty_stdin);
+        i = fixup_input(context->std_input, socket_fd, params->flags & EXEC_APPLY_TTY_STDIN);
         o = fixup_output(context->std_output, socket_fd);
 
         if (fileno == STDERR_FILENO) {
@@ -1675,7 +1675,7 @@ static int exec_child(
 
         exec_context_tty_reset(context, params);
 
-        if (params->confirm_spawn) {
+        if (params->flags & EXEC_CONFIRM_SPAWN) {
                 char response;
 
                 r = ask_for_confirmation(&response, argv);
@@ -1940,7 +1940,7 @@ static int exec_child(
 
         umask(context->umask);
 
-        if (params->apply_permissions && !command->privileged) {
+        if ((params->flags & EXEC_APPLY_PERMISSIONS) && !command->privileged) {
                 r = enforce_groups(context, username, gid);
                 if (r < 0) {
                         *exit_status = EXIT_GROUP;
@@ -2010,7 +2010,7 @@ static int exec_child(
                 }
 
                 r = setup_namespace(
-                                params->apply_chroot ? context->root_directory : NULL,
+                                (params->flags & EXEC_APPLY_CHROOT) ? context->root_directory : NULL,
                                 context->read_write_paths,
                                 context->read_only_paths,
                                 context->inaccessible_paths,
@@ -2041,7 +2041,7 @@ static int exec_child(
         else
                 wd = "/";
 
-        if (params->apply_chroot) {
+        if (params->flags & EXEC_APPLY_CHROOT) {
                 if (!needs_mount_namespace && context->root_directory)
                         if (chroot(context->root_directory) < 0) {
                                 *exit_status = EXIT_CHROOT;
@@ -2065,7 +2065,12 @@ static int exec_child(
         }
 
 #ifdef HAVE_SELINUX
-        if (params->apply_permissions && mac_selinux_use() && params->selinux_context_net && socket_fd >= 0 && !command->privileged) {
+        if ((params->flags & EXEC_APPLY_PERMISSIONS) &&
+            mac_selinux_use() &&
+            params->selinux_context_net &&
+            socket_fd >= 0 &&
+            !command->privileged) {
+
                 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;
@@ -2090,7 +2095,7 @@ static int exec_child(
                 return r;
         }
 
-        if (params->apply_permissions && !command->privileged) {
+        if ((params->flags & EXEC_APPLY_PERMISSIONS) && !command->privileged) {
 
                 bool use_address_families = context->address_families_whitelist ||
                         !set_isempty(context->address_families);
diff --git a/src/core/execute.h b/src/core/execute.h
index 48cc18fbb3..77418ea2ad 100644
--- a/src/core/execute.h
+++ b/src/core/execute.h
@@ -208,6 +208,17 @@ struct ExecContext {
         bool no_new_privileges_set:1;
 };
 
+typedef enum ExecFlags {
+        EXEC_CONFIRM_SPAWN     = 1U << 0,
+        EXEC_APPLY_PERMISSIONS = 1U << 1,
+        EXEC_APPLY_CHROOT      = 1U << 2,
+        EXEC_APPLY_TTY_STDIN   = 1U << 3,
+
+        /* The following are not usec by execute.c, but by consumers internally */
+        EXEC_PASS_FDS          = 1U << 4,
+        EXEC_IS_CONTROL        = 1U << 5,
+} ExecFlags;
+
 struct ExecParameters {
         char **argv;
         char **environment;
@@ -216,11 +227,7 @@ struct ExecParameters {
         char **fd_names;
         unsigned n_fds;
 
-        bool apply_permissions:1;
-        bool apply_chroot:1;
-        bool apply_tty_stdin:1;
-
-        bool confirm_spawn:1;
+        ExecFlags flags;
         bool selinux_context_net:1;
 
         bool cgroup_delegate:1;
diff --git a/src/core/mount.c b/src/core/mount.c
index afb20af9e2..3f6ac7fcf9 100644
--- a/src/core/mount.c
+++ b/src/core/mount.c
@@ -701,12 +701,10 @@ static int mount_spawn(Mount *m, ExecCommand *c, pid_t *_pid) {
         pid_t pid;
         int r;
         ExecParameters exec_params = {
-                .apply_permissions = true,
-                .apply_chroot      = true,
-                .apply_tty_stdin   = true,
-                .stdin_fd          = -1,
-                .stdout_fd         = -1,
-                .stderr_fd         = -1,
+                .flags      = EXEC_APPLY_PERMISSIONS|EXEC_APPLY_CHROOT|EXEC_APPLY_TTY_STDIN,
+                .stdin_fd   = -1,
+                .stdout_fd  = -1,
+                .stderr_fd  = -1,
         };
 
         assert(m);
@@ -732,7 +730,7 @@ static int mount_spawn(Mount *m, ExecCommand *c, pid_t *_pid) {
                 return r;
 
         exec_params.environment = UNIT(m)->manager->environment;
-        exec_params.confirm_spawn = UNIT(m)->manager->confirm_spawn;
+        exec_params.flags |= UNIT(m)->manager->confirm_spawn ? EXEC_CONFIRM_SPAWN : 0;
         exec_params.cgroup_supported = UNIT(m)->manager->cgroup_supported;
         exec_params.cgroup_path = UNIT(m)->cgroup_path;
         exec_params.cgroup_delegate = m->cgroup_context.delegate;
diff --git a/src/core/service.c b/src/core/service.c
index eb125cb999..b4db7d17ed 100644
--- a/src/core/service.c
+++ b/src/core/service.c
@@ -1152,11 +1152,7 @@ static int service_spawn(
                 Service *s,
                 ExecCommand *c,
                 usec_t timeout,
-                bool pass_fds,
-                bool apply_permissions,
-                bool apply_chroot,
-                bool apply_tty_stdin,
-                bool is_control,
+                ExecFlags flags,
                 pid_t *_pid) {
 
         _cleanup_strv_free_ char **argv = NULL, **final_env = NULL, **our_env = NULL, **fd_names = NULL;
@@ -1166,12 +1162,10 @@ static int service_spawn(
         pid_t pid;
 
         ExecParameters exec_params = {
-                .apply_permissions = apply_permissions,
-                .apply_chroot      = apply_chroot,
-                .apply_tty_stdin   = apply_tty_stdin,
-                .stdin_fd          = -1,
-                .stdout_fd         = -1,
-                .stderr_fd         = -1,
+                .flags      = flags,
+                .stdin_fd   = -1,
+                .stdout_fd  = -1,
+                .stderr_fd  = -1,
         };
 
         int r;
@@ -1194,7 +1188,7 @@ static int service_spawn(
         if (r < 0)
                 return r;
 
-        if (pass_fds ||
+        if ((flags & EXEC_PASS_FDS) ||
             s->exec_context.std_input == EXEC_INPUT_SOCKET ||
             s->exec_context.std_output == EXEC_OUTPUT_SOCKET ||
             s->exec_context.std_error == EXEC_OUTPUT_SOCKET) {
@@ -1218,7 +1212,7 @@ static int service_spawn(
         if (!our_env)
                 return -ENOMEM;
 
-        if (is_control ? s->notify_access == NOTIFY_ALL : s->notify_access != NOTIFY_NONE)
+        if ((flags & EXEC_IS_CONTROL) ? s->notify_access == NOTIFY_ALL : s->notify_access != NOTIFY_NONE)
                 if (asprintf(our_env + n_env++, "NOTIFY_SOCKET=%s", UNIT(s)->manager->notify_socket) < 0)
                         return -ENOMEM;
 
@@ -1226,7 +1220,7 @@ static int service_spawn(
                 if (asprintf(our_env + n_env++, "MAINPID="PID_FMT, s->main_pid) < 0)
                         return -ENOMEM;
 
-        if (!MANAGER_IS_SYSTEM(UNIT(s)->manager))
+        if (MANAGER_IS_USER(UNIT(s)->manager))
                 if (asprintf(our_env + n_env++, "MANAGERPID="PID_FMT, getpid()) < 0)
                         return -ENOMEM;
 
@@ -1266,18 +1260,18 @@ static int service_spawn(
         if (!final_env)
                 return -ENOMEM;
 
-        if (is_control && UNIT(s)->cgroup_path) {
+        if ((flags & EXEC_IS_CONTROL) && UNIT(s)->cgroup_path) {
                 path = strjoina(UNIT(s)->cgroup_path, "/control");
                 (void) cg_create(SYSTEMD_CGROUP_CONTROLLER, path);
         } else
                 path = UNIT(s)->cgroup_path;
 
         exec_params.argv = argv;
+        exec_params.environment = final_env;
         exec_params.fds = fds;
         exec_params.fd_names = fd_names;
         exec_params.n_fds = n_fds;
-        exec_params.environment = final_env;
-        exec_params.confirm_spawn = UNIT(s)->manager->confirm_spawn;
+        exec_params.flags |= UNIT(s)->manager->confirm_spawn ? EXEC_CONFIRM_SPAWN : 0;
         exec_params.cgroup_supported = UNIT(s)->manager->cgroup_supported;
         exec_params.cgroup_path = path;
         exec_params.cgroup_delegate = s->cgroup_context.delegate;
@@ -1465,11 +1459,9 @@ static void service_enter_stop_post(Service *s, ServiceResult f) {
                 r = service_spawn(s,
                                   s->control_command,
                                   s->timeout_stop_usec,
-                                  false,
-                                  !s->permissions_start_only,
-                                  !s->root_directory_start_only,
-                                  true,
-                                  true,
+                                  (s->permissions_start_only ? 0 : EXEC_APPLY_PERMISSIONS) |
+                                  (s->root_directory_start_only ? 0 : EXEC_APPLY_CHROOT) |
+                                  EXEC_APPLY_TTY_STDIN | EXEC_IS_CONTROL,
                                   &s->control_pid);
                 if (r < 0)
                         goto fail;
@@ -1580,11 +1572,9 @@ static void service_enter_stop(Service *s, ServiceResult f) {
                 r = service_spawn(s,
                                   s->control_command,
                                   s->timeout_stop_usec,
-                                  false,
-                                  !s->permissions_start_only,
-                                  !s->root_directory_start_only,
-                                  false,
-                                  true,
+                                  (s->permissions_start_only ? 0 : EXEC_APPLY_PERMISSIONS) |
+                                  (s->root_directory_start_only ? 0 : EXEC_APPLY_CHROOT) |
+                                  EXEC_IS_CONTROL,
                                   &s->control_pid);
                 if (r < 0)
                         goto fail;
@@ -1661,11 +1651,9 @@ static void service_enter_start_post(Service *s) {
                 r = service_spawn(s,
                                   s->control_command,
                                   s->timeout_start_usec,
-                                  false,
-                                  !s->permissions_start_only,
-                                  !s->root_directory_start_only,
-                                  false,
-                                  true,
+                                  (s->permissions_start_only ? 0 : EXEC_APPLY_PERMISSIONS)|
+                                  (s->root_directory_start_only ? 0 : EXEC_APPLY_CHROOT)|
+                                  EXEC_IS_CONTROL,
                                   &s->control_pid);
                 if (r < 0)
                         goto fail;
@@ -1735,11 +1723,7 @@ static void service_enter_start(Service *s) {
         r = service_spawn(s,
                           c,
                           timeout,
-                          true,
-                          true,
-                          true,
-                          true,
-                          false,
+                          EXEC_PASS_FDS|EXEC_APPLY_PERMISSIONS|EXEC_APPLY_CHROOT|EXEC_APPLY_TTY_STDIN,
                           &pid);
         if (r < 0)
                 goto fail;
@@ -1798,11 +1782,9 @@ static void service_enter_start_pre(Service *s) {
                 r = service_spawn(s,
                                   s->control_command,
                                   s->timeout_start_usec,
-                                  false,
-                                  !s->permissions_start_only,
-                                  !s->root_directory_start_only,
-                                  true,
-                                  true,
+                                  (s->permissions_start_only ? 0 : EXEC_APPLY_PERMISSIONS) |
+                                  (s->root_directory_start_only ? 0: EXEC_APPLY_CHROOT) |
+                                  EXEC_IS_CONTROL|EXEC_APPLY_TTY_STDIN,
                                   &s->control_pid);
                 if (r < 0)
                         goto fail;
@@ -1877,11 +1859,9 @@ static void service_enter_reload(Service *s) {
                 r = service_spawn(s,
                                   s->control_command,
                                   s->timeout_start_usec,
-                                  false,
-                                  !s->permissions_start_only,
-                                  !s->root_directory_start_only,
-                                  false,
-                                  true,
+                                  (s->permissions_start_only ? 0 : EXEC_APPLY_PERMISSIONS) |
+                                  (s->root_directory_start_only ? 0 : EXEC_APPLY_CHROOT) |
+                                  EXEC_IS_CONTROL,
                                   &s->control_pid);
                 if (r < 0)
                         goto fail;
@@ -1919,12 +1899,10 @@ static void service_run_next_control(Service *s) {
         r = service_spawn(s,
                           s->control_command,
                           timeout,
-                          false,
-                          !s->permissions_start_only,
-                          !s->root_directory_start_only,
-                          s->control_command_id == SERVICE_EXEC_START_PRE ||
-                          s->control_command_id == SERVICE_EXEC_STOP_POST,
-                          true,
+                          (s->permissions_start_only ? 0 : EXEC_APPLY_PERMISSIONS) |
+                          (s->root_directory_start_only ? 0 : EXEC_APPLY_CHROOT) |
+                          (IN_SET(s->control_command_id, SERVICE_EXEC_START_PRE, SERVICE_EXEC_STOP_POST) ? EXEC_APPLY_TTY_STDIN : 0)|
+                          EXEC_IS_CONTROL,
                           &s->control_pid);
         if (r < 0)
                 goto fail;
@@ -1962,11 +1940,7 @@ static void service_run_next_main(Service *s) {
         r = service_spawn(s,
                           s->main_command,
                           s->timeout_start_usec,
-                          true,
-                          true,
-                          true,
-                          true,
-                          false,
+                          EXEC_PASS_FDS|EXEC_APPLY_PERMISSIONS|EXEC_APPLY_CHROOT|EXEC_APPLY_TTY_STDIN,
                           &pid);
         if (r < 0)
                 goto fail;
diff --git a/src/core/socket.c b/src/core/socket.c
index ff55885fb3..82363e2157 100644
--- a/src/core/socket.c
+++ b/src/core/socket.c
@@ -1664,12 +1664,10 @@ static int socket_spawn(Socket *s, ExecCommand *c, pid_t *_pid) {
         pid_t pid;
         int r;
         ExecParameters exec_params = {
-                .apply_permissions = true,
-                .apply_chroot      = true,
-                .apply_tty_stdin   = true,
-                .stdin_fd          = -1,
-                .stdout_fd         = -1,
-                .stderr_fd         = -1,
+                .flags      = EXEC_APPLY_PERMISSIONS|EXEC_APPLY_CHROOT|EXEC_APPLY_TTY_STDIN,
+                .stdin_fd   = -1,
+                .stdout_fd  = -1,
+                .stderr_fd  = -1,
         };
 
         assert(s);
@@ -1700,7 +1698,7 @@ static int socket_spawn(Socket *s, ExecCommand *c, pid_t *_pid) {
 
         exec_params.argv = argv;
         exec_params.environment = UNIT(s)->manager->environment;
-        exec_params.confirm_spawn = UNIT(s)->manager->confirm_spawn;
+        exec_params.flags |= UNIT(s)->manager->confirm_spawn ? EXEC_CONFIRM_SPAWN : 0;
         exec_params.cgroup_supported = UNIT(s)->manager->cgroup_supported;
         exec_params.cgroup_path = UNIT(s)->cgroup_path;
         exec_params.cgroup_delegate = s->cgroup_context.delegate;
diff --git a/src/core/swap.c b/src/core/swap.c
index 66a318d01f..0ba4c4d881 100644
--- a/src/core/swap.c
+++ b/src/core/swap.c
@@ -611,12 +611,10 @@ static int swap_spawn(Swap *s, ExecCommand *c, pid_t *_pid) {
         pid_t pid;
         int r;
         ExecParameters exec_params = {
-                .apply_permissions = true,
-                .apply_chroot      = true,
-                .apply_tty_stdin   = true,
-                .stdin_fd          = -1,
-                .stdout_fd         = -1,
-                .stderr_fd         = -1,
+                .flags     = EXEC_APPLY_PERMISSIONS|EXEC_APPLY_CHROOT|EXEC_APPLY_TTY_STDIN,
+                .stdin_fd  = -1,
+                .stdout_fd = -1,
+                .stderr_fd = -1,
         };
 
         assert(s);
@@ -642,7 +640,7 @@ static int swap_spawn(Swap *s, ExecCommand *c, pid_t *_pid) {
                 goto fail;
 
         exec_params.environment = UNIT(s)->manager->environment;
-        exec_params.confirm_spawn = UNIT(s)->manager->confirm_spawn;
+        exec_params.flags |= UNIT(s)->manager->confirm_spawn ? EXEC_CONFIRM_SPAWN : 0;
         exec_params.cgroup_supported = UNIT(s)->manager->cgroup_supported;
         exec_params.cgroup_path = UNIT(s)->cgroup_path;
         exec_params.cgroup_delegate = s->cgroup_context.delegate;