src/core/service.h

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2 #pragma once
   3
   4 typedef struct Service Service;
   5 typedef struct ServiceFDStore ServiceFDStore;
   6
   7 #include "exit-status.h"
   8 #include "kill.h"
   9 #include "open-file.h"
  10 #include "path.h"
  11 #include "ratelimit.h"
  12 #include "socket.h"
  13 #include "unit.h"
  14
  15 typedef enum ServiceRestart {
  16         SERVICE_RESTART_NO,
  17         SERVICE_RESTART_ON_SUCCESS,
  18         SERVICE_RESTART_ON_FAILURE,
  19         SERVICE_RESTART_ON_ABNORMAL,
  20         SERVICE_RESTART_ON_WATCHDOG,
  21         SERVICE_RESTART_ON_ABORT,
  22         SERVICE_RESTART_ALWAYS,
  23         _SERVICE_RESTART_MAX,
  24         _SERVICE_RESTART_INVALID = -EINVAL,
  25 } ServiceRestart;
  26
  27 typedef enum ServiceType {
  28         SERVICE_SIMPLE,   /* we fork and go on right-away (i.e. modern socket activated daemons) */
  29         SERVICE_FORKING,  /* forks by itself (i.e. traditional daemons) */
  30         SERVICE_ONESHOT,  /* we fork and wait until the program finishes (i.e. programs like fsck which run and need to finish before we continue) */
  31         SERVICE_DBUS,     /* we fork and wait until a specific D-Bus name appears on the bus */
  32         SERVICE_NOTIFY,   /* we fork and wait until a daemon sends us a ready message with sd_notify() */
  33         SERVICE_IDLE,     /* much like simple, but delay exec() until all jobs are dispatched. */
  34         SERVICE_EXEC,     /* we fork and wait until we execute exec() (this means our own setup is waited for) */
  35         _SERVICE_TYPE_MAX,
  36         _SERVICE_TYPE_INVALID = -EINVAL,
  37 } ServiceType;
  38
  39 typedef enum ServiceExitType {
  40         SERVICE_EXIT_MAIN,    /* we consider the main PID when deciding if the service exited */
  41         SERVICE_EXIT_CGROUP,  /* we wait for the last process in the cgroup to exit */
  42         _SERVICE_EXIT_TYPE_MAX,
  43         _SERVICE_EXIT_TYPE_INVALID = -EINVAL,
  44 } ServiceExitType;
  45
  46 typedef enum ServiceExecCommand {
  47         SERVICE_EXEC_CONDITION,
  48         SERVICE_EXEC_START_PRE,
  49         SERVICE_EXEC_START,
  50         SERVICE_EXEC_START_POST,
  51         SERVICE_EXEC_RELOAD,
  52         SERVICE_EXEC_STOP,
  53         SERVICE_EXEC_STOP_POST,
  54         _SERVICE_EXEC_COMMAND_MAX,
  55         _SERVICE_EXEC_COMMAND_INVALID = -EINVAL,
  56 } ServiceExecCommand;
  57
  58 typedef enum NotifyState {
  59         NOTIFY_UNKNOWN,
  60         NOTIFY_READY,
  61         NOTIFY_RELOADING,
  62         NOTIFY_STOPPING,
  63         _NOTIFY_STATE_MAX,
  64         _NOTIFY_STATE_INVALID = -EINVAL,
  65 } NotifyState;
  66
  67 /* The values of this enum are referenced in man/systemd.exec.xml and src/shared/bus-unit-util.c.
  68  * Update those sources for each change to this enum. */
  69 typedef enum ServiceResult {
  70         SERVICE_SUCCESS,
  71         SERVICE_FAILURE_RESOURCES, /* a bit of a misnomer, just our catch-all error for errnos we didn't expect */
  72         SERVICE_FAILURE_PROTOCOL,
  73         SERVICE_FAILURE_TIMEOUT,
  74         SERVICE_FAILURE_EXIT_CODE,
  75         SERVICE_FAILURE_SIGNAL,
  76         SERVICE_FAILURE_CORE_DUMP,
  77         SERVICE_FAILURE_WATCHDOG,
  78         SERVICE_FAILURE_START_LIMIT_HIT,
  79         SERVICE_FAILURE_OOM_KILL, /* OOM Kill by the Kernel or systemd-oomd */
  80         SERVICE_SKIP_CONDITION,
  81         _SERVICE_RESULT_MAX,
  82         _SERVICE_RESULT_INVALID = -EINVAL,
  83 } ServiceResult;
  84
  85 typedef enum ServiceTimeoutFailureMode {
  86         SERVICE_TIMEOUT_TERMINATE,
  87         SERVICE_TIMEOUT_ABORT,
  88         SERVICE_TIMEOUT_KILL,
  89         _SERVICE_TIMEOUT_FAILURE_MODE_MAX,
  90         _SERVICE_TIMEOUT_FAILURE_MODE_INVALID = -EINVAL,
  91 } ServiceTimeoutFailureMode;
  92
  93 struct ServiceFDStore {
  94         Service *service;
  95
  96         int fd;
  97         char *fdname;
  98         sd_event_source *event_source;
  99         bool do_poll;
 100
 101         LIST_FIELDS(ServiceFDStore, fd_store);
 102 };
 103
 104 struct Service {
 105         Unit meta;
 106
 107         ServiceType type;
 108         ServiceExitType exit_type;
 109         ServiceRestart restart;
 110         ExitStatusSet restart_prevent_status;
 111         ExitStatusSet restart_force_status;
 112         ExitStatusSet success_status;
 113
 114         /* If set we'll read the main daemon PID from this file */
 115         char *pid_file;
 116
 117         usec_t restart_usec;
 118         usec_t timeout_start_usec;
 119         usec_t timeout_stop_usec;
 120         usec_t timeout_abort_usec;
 121         bool timeout_abort_set;
 122         usec_t runtime_max_usec;
 123         usec_t runtime_rand_extra_usec;
 124         ServiceTimeoutFailureMode timeout_start_failure_mode;
 125         ServiceTimeoutFailureMode timeout_stop_failure_mode;
 126
 127         dual_timestamp watchdog_timestamp;
 128         usec_t watchdog_usec;            /* the requested watchdog timeout in the unit file */
 129         usec_t watchdog_original_usec;   /* the watchdog timeout that was in effect when the unit was started, i.e. the timeout the forked off processes currently see */
 130         usec_t watchdog_override_usec;   /* the watchdog timeout requested by the service itself through sd_notify() */
 131         bool watchdog_override_enable;
 132         sd_event_source *watchdog_event_source;
 133
 134         ExecCommand* exec_command[_SERVICE_EXEC_COMMAND_MAX];
 135
 136         ExecContext exec_context;
 137         KillContext kill_context;
 138         CGroupContext cgroup_context;
 139
 140         ServiceState state, deserialized_state;
 141
 142         /* The exit status of the real main process */
 143         ExecStatus main_exec_status;
 144
 145         /* The currently executed control process */
 146         ExecCommand *control_command;
 147
 148         /* The currently executed main process, which may be NULL if
 149          * the main process got started via forking mode and not by
 150          * us */
 151         ExecCommand *main_command;
 152
 153         /* The ID of the control command currently being executed */
 154         ServiceExecCommand control_command_id;
 155
 156         /* Runtime data of the execution context */
 157         ExecRuntime *exec_runtime;
 158         DynamicCreds dynamic_creds;
 159
 160         pid_t main_pid, control_pid;
 161
 162         /* if we are a socket activated service instance, store information of the connection/peer/socket */
 163         int socket_fd;
 164         SocketPeer *socket_peer;
 165         UnitRef accept_socket;
 166         bool socket_fd_selinux_context_net;
 167
 168         bool permissions_start_only;
 169         bool root_directory_start_only;
 170         bool remain_after_exit;
 171         bool guess_main_pid;
 172
 173         /* If we shut down, remember why */
 174         ServiceResult result;
 175         ServiceResult reload_result;
 176         ServiceResult clean_result;
 177
 178         bool main_pid_known:1;
 179         bool main_pid_alien:1;
 180         bool bus_name_good:1;
 181         bool forbid_restart:1;
 182         /* Keep restart intention between UNIT_FAILED and UNIT_ACTIVATING */
 183         bool will_auto_restart:1;
 184         bool start_timeout_defined:1;
 185         bool exec_fd_hot:1;
 186
 187         char *bus_name;
 188         char *bus_name_owner; /* unique name of the current owner */
 189
 190         char *status_text;
 191         int status_errno;
 192
 193         sd_event_source *timer_event_source;
 194         PathSpec *pid_file_pathspec;
 195
 196         NotifyAccess notify_access;
 197         NotifyState notify_state;
 198
 199         sd_bus_slot *bus_name_pid_lookup_slot;
 200
 201         sd_event_source *exec_fd_event_source;
 202
 203         ServiceFDStore *fd_store;
 204         size_t n_fd_store;
 205         unsigned n_fd_store_max;
 206         unsigned n_keep_fd_store;
 207
 208         char *usb_function_descriptors;
 209         char *usb_function_strings;
 210
 211         int stdin_fd;
 212         int stdout_fd;
 213         int stderr_fd;
 214
 215         unsigned n_restarts;
 216         bool flush_n_restarts;
 217
 218         OOMPolicy oom_policy;
 219
 220         LIST_HEAD(OpenFile, open_files);
 221 };
 222
 223 static inline usec_t service_timeout_abort_usec(Service *s) {
 224         assert(s);
 225         return s->timeout_abort_set ? s->timeout_abort_usec : s->timeout_stop_usec;
 226 }
 227
 228 static inline usec_t service_get_watchdog_usec(Service *s) {
 229         assert(s);
 230         return s->watchdog_override_enable ? s->watchdog_override_usec : s->watchdog_original_usec;
 231 }
 232
 233 extern const UnitVTable service_vtable;
 234
 235 int service_set_socket_fd(Service *s, int fd, struct Socket *socket, struct SocketPeer *peer, bool selinux_context_net);
 236 void service_close_socket_fd(Service *s);
 237
 238 const char* service_restart_to_string(ServiceRestart i) _const_;
 239 ServiceRestart service_restart_from_string(const char *s) _pure_;
 240
 241 const char* service_type_to_string(ServiceType i) _const_;
 242 ServiceType service_type_from_string(const char *s) _pure_;
 243
 244 const char* service_exit_type_to_string(ServiceExitType i) _const_;
 245 ServiceExitType service_exit_type_from_string(const char *s) _pure_;
 246
 247 const char* service_exec_command_to_string(ServiceExecCommand i) _const_;
 248 ServiceExecCommand service_exec_command_from_string(const char *s) _pure_;
 249
 250 const char* service_exec_ex_command_to_string(ServiceExecCommand i) _const_;
 251 ServiceExecCommand service_exec_ex_command_from_string(const char *s) _pure_;
 252
 253 const char* notify_state_to_string(NotifyState i) _const_;
 254 NotifyState notify_state_from_string(const char *s) _pure_;
 255
 256 const char* service_result_to_string(ServiceResult i) _const_;
 257 ServiceResult service_result_from_string(const char *s) _pure_;
 258
 259 const char* service_timeout_failure_mode_to_string(ServiceTimeoutFailureMode i) _const_;
 260 ServiceTimeoutFailureMode service_timeout_failure_mode_from_string(const char *s) _pure_;
 261
 262 DEFINE_CAST(SERVICE, Service);
 263
 264 #define STATUS_TEXT_MAX (16U*1024U)
 265
 266 /* Only exported for unit tests */
 267 int service_deserialize_exec_command(Unit *u, const char *key, const char *value);