src/core/execute.h

   1 #pragma once
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2010 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU Lesser General Public License as published by
  10   the Free Software Foundation; either version 2.1 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   Lesser General Public License for more details.
  17
  18   You should have received a copy of the GNU Lesser General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 typedef struct ExecStatus ExecStatus;
  23 typedef struct ExecCommand ExecCommand;
  24 typedef struct ExecContext ExecContext;
  25 typedef struct ExecRuntime ExecRuntime;
  26 typedef struct ExecParameters ExecParameters;
  27
  28 #include <sched.h>
  29 #include <stdbool.h>
  30 #include <stdio.h>
  31 #include <sys/capability.h>
  32
  33 #include "cgroup-util.h"
  34 #include "fdset.h"
  35 #include "list.h"
  36 #include "missing.h"
  37 #include "namespace.h"
  38 #include "nsflags.h"
  39
  40 typedef enum ExecUtmpMode {
  41         EXEC_UTMP_INIT,
  42         EXEC_UTMP_LOGIN,
  43         EXEC_UTMP_USER,
  44         _EXEC_UTMP_MODE_MAX,
  45         _EXEC_UTMP_MODE_INVALID = -1
  46 } ExecUtmpMode;
  47
  48 typedef enum ExecInput {
  49         EXEC_INPUT_NULL,
  50         EXEC_INPUT_TTY,
  51         EXEC_INPUT_TTY_FORCE,
  52         EXEC_INPUT_TTY_FAIL,
  53         EXEC_INPUT_SOCKET,
  54         EXEC_INPUT_NAMED_FD,
  55         _EXEC_INPUT_MAX,
  56         _EXEC_INPUT_INVALID = -1
  57 } ExecInput;
  58
  59 typedef enum ExecOutput {
  60         EXEC_OUTPUT_INHERIT,
  61         EXEC_OUTPUT_NULL,
  62         EXEC_OUTPUT_TTY,
  63         EXEC_OUTPUT_SYSLOG,
  64         EXEC_OUTPUT_SYSLOG_AND_CONSOLE,
  65         EXEC_OUTPUT_KMSG,
  66         EXEC_OUTPUT_KMSG_AND_CONSOLE,
  67         EXEC_OUTPUT_JOURNAL,
  68         EXEC_OUTPUT_JOURNAL_AND_CONSOLE,
  69         EXEC_OUTPUT_SOCKET,
  70         EXEC_OUTPUT_NAMED_FD,
  71         _EXEC_OUTPUT_MAX,
  72         _EXEC_OUTPUT_INVALID = -1
  73 } ExecOutput;
  74
  75 typedef enum ExecPreserveMode {
  76         EXEC_PRESERVE_NO,
  77         EXEC_PRESERVE_YES,
  78         EXEC_PRESERVE_RESTART,
  79         _EXEC_PRESERVE_MODE_MAX,
  80         _EXEC_PRESERVE_MODE_INVALID = -1
  81 } ExecPreserveMode;
  82
  83 struct ExecStatus {
  84         dual_timestamp start_timestamp;
  85         dual_timestamp exit_timestamp;
  86         pid_t pid;
  87         int code;     /* as in siginfo_t::si_code */
  88         int status;   /* as in sigingo_t::si_status */
  89 };
  90
  91 struct ExecCommand {
  92         char *path;
  93         char **argv;
  94         ExecStatus exec_status;
  95         LIST_FIELDS(ExecCommand, command); /* useful for chaining commands */
  96         bool ignore:1;
  97         bool privileged:1;
  98 };
  99
 100 struct ExecRuntime {
 101         int n_ref;
 102
 103         char *tmp_dir;
 104         char *var_tmp_dir;
 105
 106         /* An AF_UNIX socket pair, that contains a datagram containing a file descriptor referring to the network
 107          * namespace. */
 108         int netns_storage_socket[2];
 109 };
 110
 111 typedef enum ExecDirectoryType {
 112         EXEC_DIRECTORY_RUNTIME = 0,
 113         EXEC_DIRECTORY_STATE,
 114         EXEC_DIRECTORY_CACHE,
 115         EXEC_DIRECTORY_LOGS,
 116         EXEC_DIRECTORY_CONFIGURATION,
 117         _EXEC_DIRECTORY_MAX,
 118         _EXEC_DIRECTORY_INVALID = -1,
 119 } ExecDirectoryType;
 120
 121 typedef struct ExecDirectory {
 122         char **paths;
 123         mode_t mode;
 124 } ExecDirectory;
 125
 126 struct ExecContext {
 127         char **environment;
 128         char **environment_files;
 129         char **pass_environment;
 130
 131         struct rlimit *rlimit[_RLIMIT_MAX];
 132         char *working_directory, *root_directory, *root_image;
 133         bool working_directory_missing_ok;
 134         bool working_directory_home;
 135
 136         mode_t umask;
 137         int oom_score_adjust;
 138         int nice;
 139         int ioprio;
 140         int cpu_sched_policy;
 141         int cpu_sched_priority;
 142
 143         cpu_set_t *cpuset;
 144         unsigned cpuset_ncpus;
 145
 146         ExecInput std_input;
 147         ExecOutput std_output;
 148         ExecOutput std_error;
 149         char *stdio_fdname[3];
 150
 151         nsec_t timer_slack_nsec;
 152
 153         bool stdio_as_fds;
 154
 155         char *tty_path;
 156
 157         bool tty_reset;
 158         bool tty_vhangup;
 159         bool tty_vt_disallocate;
 160
 161         bool ignore_sigpipe;
 162
 163         /* Since resolving these names might involve socket
 164          * connections and we don't want to deadlock ourselves these
 165          * names are resolved on execution only and in the child
 166          * process. */
 167         char *user;
 168         char *group;
 169         char **supplementary_groups;
 170
 171         char *pam_name;
 172
 173         char *utmp_id;
 174         ExecUtmpMode utmp_mode;
 175
 176         bool selinux_context_ignore;
 177         char *selinux_context;
 178
 179         bool apparmor_profile_ignore;
 180         char *apparmor_profile;
 181
 182         bool smack_process_label_ignore;
 183         char *smack_process_label;
 184
 185         char **read_write_paths, **read_only_paths, **inaccessible_paths;
 186         unsigned long mount_flags;
 187         BindMount *bind_mounts;
 188         unsigned n_bind_mounts;
 189
 190         uint64_t capability_bounding_set;
 191         uint64_t capability_ambient_set;
 192         int secure_bits;
 193
 194         int syslog_priority;
 195         char *syslog_identifier;
 196         bool syslog_level_prefix;
 197
 198         bool cpu_sched_reset_on_fork;
 199         bool non_blocking;
 200         bool private_tmp;
 201         bool private_network;
 202         bool private_devices;
 203         bool private_users;
 204         ProtectSystem protect_system;
 205         ProtectHome protect_home;
 206         bool protect_kernel_tunables;
 207         bool protect_kernel_modules;
 208         bool protect_control_groups;
 209         bool mount_apivfs;
 210
 211         bool no_new_privileges;
 212
 213         bool dynamic_user;
 214         bool remove_ipc;
 215
 216         /* This is not exposed to the user but available
 217          * internally. We need it to make sure that whenever we spawn
 218          * /usr/bin/mount it is run in the same process group as us so
 219          * that the autofs logic detects that it belongs to us and we
 220          * don't enter a trigger loop. */
 221         bool same_pgrp;
 222
 223         unsigned long personality;
 224
 225         unsigned long restrict_namespaces; /* The CLONE_NEWxyz flags permitted to the unit's processes */
 226
 227         Set *syscall_filter;
 228         Set *syscall_archs;
 229         int syscall_errno;
 230         bool syscall_whitelist:1;
 231
 232         Set *address_families;
 233         bool address_families_whitelist:1;
 234
 235         ExecPreserveMode runtime_directory_preserve_mode;
 236         ExecDirectory directories[_EXEC_DIRECTORY_MAX];
 237
 238         bool memory_deny_write_execute;
 239         bool restrict_realtime;
 240
 241         bool oom_score_adjust_set:1;
 242         bool nice_set:1;
 243         bool ioprio_set:1;
 244         bool cpu_sched_set:1;
 245 };
 246
 247 static inline bool exec_context_restrict_namespaces_set(const ExecContext *c) {
 248         assert(c);
 249
 250         return (c->restrict_namespaces & NAMESPACE_FLAGS_ALL) != NAMESPACE_FLAGS_ALL;
 251 }
 252
 253 typedef enum ExecFlags {
 254         EXEC_APPLY_PERMISSIONS = 1U << 0,
 255         EXEC_APPLY_CHROOT      = 1U << 1,
 256         EXEC_APPLY_TTY_STDIN   = 1U << 2,
 257         EXEC_NEW_KEYRING       = 1U << 3,
 258
 259         /* The following are not used by execute.c, but by consumers internally */
 260         EXEC_PASS_FDS          = 1U << 4,
 261         EXEC_IS_CONTROL        = 1U << 5,
 262         EXEC_SETENV_RESULT     = 1U << 6,
 263         EXEC_SET_WATCHDOG      = 1U << 7,
 264 } ExecFlags;
 265
 266 struct ExecParameters {
 267         char **argv;
 268         char **environment;
 269
 270         int *fds;
 271         char **fd_names;
 272         unsigned n_storage_fds;
 273         unsigned n_socket_fds;
 274
 275         ExecFlags flags;
 276         bool selinux_context_net:1;
 277
 278         bool cgroup_delegate:1;
 279         CGroupMask cgroup_supported;
 280         const char *cgroup_path;
 281
 282         char **prefix;
 283
 284         const char *confirm_spawn;
 285
 286         usec_t watchdog_usec;
 287
 288         int *idle_pipe;
 289
 290         int stdin_fd;
 291         int stdout_fd;
 292         int stderr_fd;
 293 };
 294
 295 #include "unit.h"
 296 #include "dynamic-user.h"
 297
 298 int exec_spawn(Unit *unit,
 299                ExecCommand *command,
 300                const ExecContext *context,
 301                const ExecParameters *exec_params,
 302                ExecRuntime *runtime,
 303                DynamicCreds *dynamic_creds,
 304                pid_t *ret);
 305
 306 void exec_command_done(ExecCommand *c);
 307 void exec_command_done_array(ExecCommand *c, unsigned n);
 308
 309 ExecCommand* exec_command_free_list(ExecCommand *c);
 310 void exec_command_free_array(ExecCommand **c, unsigned n);
 311
 312 char *exec_command_line(char **argv);
 313
 314 void exec_command_dump(ExecCommand *c, FILE *f, const char *prefix);
 315 void exec_command_dump_list(ExecCommand *c, FILE *f, const char *prefix);
 316 void exec_command_append_list(ExecCommand **l, ExecCommand *e);
 317 int exec_command_set(ExecCommand *c, const char *path, ...);
 318 int exec_command_append(ExecCommand *c, const char *path, ...);
 319
 320 void exec_context_init(ExecContext *c);
 321 void exec_context_done(ExecContext *c);
 322 void exec_context_dump(ExecContext *c, FILE* f, const char *prefix);
 323
 324 int exec_context_destroy_runtime_directory(ExecContext *c, const char *runtime_root);
 325
 326 int exec_context_load_environment(Unit *unit, const ExecContext *c, char ***l);
 327 int exec_context_named_iofds(Unit *unit, const ExecContext *c, const ExecParameters *p, int named_iofds[3]);
 328 const char* exec_context_fdname(const ExecContext *c, int fd_index);
 329
 330 bool exec_context_may_touch_console(ExecContext *c);
 331 bool exec_context_maintains_privileges(ExecContext *c);
 332
 333 int exec_context_get_effective_ioprio(ExecContext *c);
 334
 335 void exec_status_start(ExecStatus *s, pid_t pid);
 336 void exec_status_exit(ExecStatus *s, ExecContext *context, pid_t pid, int code, int status);
 337 void exec_status_dump(ExecStatus *s, FILE *f, const char *prefix);
 338
 339 int exec_runtime_make(ExecRuntime **rt, ExecContext *c, const char *id);
 340 ExecRuntime *exec_runtime_ref(ExecRuntime *r);
 341 ExecRuntime *exec_runtime_unref(ExecRuntime *r);
 342
 343 int exec_runtime_serialize(Unit *unit, ExecRuntime *rt, FILE *f, FDSet *fds);
 344 int exec_runtime_deserialize_item(Unit *unit, ExecRuntime **rt, const char *key, const char *value, FDSet *fds);
 345
 346 void exec_runtime_destroy(ExecRuntime *rt);
 347
 348 const char* exec_output_to_string(ExecOutput i) _const_;
 349 ExecOutput exec_output_from_string(const char *s) _pure_;
 350
 351 const char* exec_input_to_string(ExecInput i) _const_;
 352 ExecInput exec_input_from_string(const char *s) _pure_;
 353
 354 const char* exec_utmp_mode_to_string(ExecUtmpMode i) _const_;
 355 ExecUtmpMode exec_utmp_mode_from_string(const char *s) _pure_;
 356
 357 const char* exec_preserve_mode_to_string(ExecPreserveMode i) _const_;
 358 ExecPreserveMode exec_preserve_mode_from_string(const char *s) _pure_;
 359
 360 const char* exec_directory_type_to_string(ExecDirectoryType i) _const_;
 361 ExecDirectoryType exec_directory_type_from_string(const char *s) _pure_;