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 struct ExecContext {
 112         char **environment;
 113         char **environment_files;
 114         char **pass_environment;
 115
 116         struct rlimit *rlimit[_RLIMIT_MAX];
 117         char *working_directory, *root_directory, *root_image;
 118         bool working_directory_missing_ok;
 119         bool working_directory_home;
 120
 121         mode_t umask;
 122         int oom_score_adjust;
 123         int nice;
 124         int ioprio;
 125         int cpu_sched_policy;
 126         int cpu_sched_priority;
 127
 128         cpu_set_t *cpuset;
 129         unsigned cpuset_ncpus;
 130
 131         ExecInput std_input;
 132         ExecOutput std_output;
 133         ExecOutput std_error;
 134         char *stdio_fdname[3];
 135
 136         nsec_t timer_slack_nsec;
 137
 138         bool stdio_as_fds;
 139
 140         char *tty_path;
 141
 142         bool tty_reset;
 143         bool tty_vhangup;
 144         bool tty_vt_disallocate;
 145
 146         bool ignore_sigpipe;
 147
 148         /* Since resolving these names might involve socket
 149          * connections and we don't want to deadlock ourselves these
 150          * names are resolved on execution only and in the child
 151          * process. */
 152         char *user;
 153         char *group;
 154         char **supplementary_groups;
 155
 156         char *pam_name;
 157
 158         char *utmp_id;
 159         ExecUtmpMode utmp_mode;
 160
 161         bool selinux_context_ignore;
 162         char *selinux_context;
 163
 164         bool apparmor_profile_ignore;
 165         char *apparmor_profile;
 166
 167         bool smack_process_label_ignore;
 168         char *smack_process_label;
 169
 170         char **read_write_paths, **read_only_paths, **inaccessible_paths;
 171         unsigned long mount_flags;
 172         BindMount *bind_mounts;
 173         unsigned n_bind_mounts;
 174
 175         uint64_t capability_bounding_set;
 176         uint64_t capability_ambient_set;
 177         int secure_bits;
 178
 179         int syslog_priority;
 180         char *syslog_identifier;
 181         bool syslog_level_prefix;
 182
 183         bool cpu_sched_reset_on_fork;
 184         bool non_blocking;
 185         bool private_tmp;
 186         bool private_network;
 187         bool private_devices;
 188         bool private_users;
 189         ProtectSystem protect_system;
 190         ProtectHome protect_home;
 191         bool protect_kernel_tunables;
 192         bool protect_kernel_modules;
 193         bool protect_control_groups;
 194         bool mount_apivfs;
 195
 196         bool no_new_privileges;
 197
 198         bool dynamic_user;
 199         bool remove_ipc;
 200
 201         /* This is not exposed to the user but available
 202          * internally. We need it to make sure that whenever we spawn
 203          * /usr/bin/mount it is run in the same process group as us so
 204          * that the autofs logic detects that it belongs to us and we
 205          * don't enter a trigger loop. */
 206         bool same_pgrp;
 207
 208         unsigned long personality;
 209
 210         unsigned long restrict_namespaces; /* The CLONE_NEWxyz flags permitted to the unit's processes */
 211
 212         Set *syscall_filter;
 213         Set *syscall_archs;
 214         int syscall_errno;
 215         bool syscall_whitelist:1;
 216
 217         Set *address_families;
 218         bool address_families_whitelist:1;
 219
 220         char **runtime_directory;
 221         mode_t runtime_directory_mode;
 222         ExecPreserveMode runtime_directory_preserve_mode;
 223
 224         bool memory_deny_write_execute;
 225         bool restrict_realtime;
 226
 227         bool oom_score_adjust_set:1;
 228         bool nice_set:1;
 229         bool ioprio_set:1;
 230         bool cpu_sched_set:1;
 231 };
 232
 233 static inline bool exec_context_restrict_namespaces_set(const ExecContext *c) {
 234         assert(c);
 235
 236         return (c->restrict_namespaces & NAMESPACE_FLAGS_ALL) != NAMESPACE_FLAGS_ALL;
 237 }
 238
 239 typedef enum ExecFlags {
 240         EXEC_APPLY_PERMISSIONS = 1U << 0,
 241         EXEC_APPLY_CHROOT      = 1U << 1,
 242         EXEC_APPLY_TTY_STDIN   = 1U << 2,
 243         EXEC_NEW_KEYRING       = 1U << 3,
 244
 245         /* The following are not used by execute.c, but by consumers internally */
 246         EXEC_PASS_FDS          = 1U << 4,
 247         EXEC_IS_CONTROL        = 1U << 5,
 248         EXEC_SETENV_RESULT     = 1U << 6,
 249         EXEC_SET_WATCHDOG      = 1U << 7,
 250 } ExecFlags;
 251
 252 struct ExecParameters {
 253         char **argv;
 254         char **environment;
 255
 256         int *fds;
 257         char **fd_names;
 258         unsigned n_storage_fds;
 259         unsigned n_socket_fds;
 260
 261         ExecFlags flags;
 262         bool selinux_context_net:1;
 263
 264         bool cgroup_delegate:1;
 265         CGroupMask cgroup_supported;
 266         const char *cgroup_path;
 267
 268         const char *runtime_prefix;
 269
 270         const char *confirm_spawn;
 271
 272         usec_t watchdog_usec;
 273
 274         int *idle_pipe;
 275
 276         int stdin_fd;
 277         int stdout_fd;
 278         int stderr_fd;
 279 };
 280
 281 #include "unit.h"
 282 #include "dynamic-user.h"
 283
 284 int exec_spawn(Unit *unit,
 285                ExecCommand *command,
 286                const ExecContext *context,
 287                const ExecParameters *exec_params,
 288                ExecRuntime *runtime,
 289                DynamicCreds *dynamic_creds,
 290                pid_t *ret);
 291
 292 void exec_command_done(ExecCommand *c);
 293 void exec_command_done_array(ExecCommand *c, unsigned n);
 294
 295 ExecCommand* exec_command_free_list(ExecCommand *c);
 296 void exec_command_free_array(ExecCommand **c, unsigned n);
 297
 298 char *exec_command_line(char **argv);
 299
 300 void exec_command_dump(ExecCommand *c, FILE *f, const char *prefix);
 301 void exec_command_dump_list(ExecCommand *c, FILE *f, const char *prefix);
 302 void exec_command_append_list(ExecCommand **l, ExecCommand *e);
 303 int exec_command_set(ExecCommand *c, const char *path, ...);
 304 int exec_command_append(ExecCommand *c, const char *path, ...);
 305
 306 void exec_context_init(ExecContext *c);
 307 void exec_context_done(ExecContext *c);
 308 void exec_context_dump(ExecContext *c, FILE* f, const char *prefix);
 309
 310 int exec_context_destroy_runtime_directory(ExecContext *c, const char *runtime_root);
 311
 312 int exec_context_load_environment(Unit *unit, const ExecContext *c, char ***l);
 313 int exec_context_named_iofds(Unit *unit, const ExecContext *c, const ExecParameters *p, int named_iofds[3]);
 314 const char* exec_context_fdname(const ExecContext *c, int fd_index);
 315
 316 bool exec_context_may_touch_console(ExecContext *c);
 317 bool exec_context_maintains_privileges(ExecContext *c);
 318
 319 int exec_context_get_effective_ioprio(ExecContext *c);
 320
 321 void exec_status_start(ExecStatus *s, pid_t pid);
 322 void exec_status_exit(ExecStatus *s, ExecContext *context, pid_t pid, int code, int status);
 323 void exec_status_dump(ExecStatus *s, FILE *f, const char *prefix);
 324
 325 int exec_runtime_make(ExecRuntime **rt, ExecContext *c, const char *id);
 326 ExecRuntime *exec_runtime_ref(ExecRuntime *r);
 327 ExecRuntime *exec_runtime_unref(ExecRuntime *r);
 328
 329 int exec_runtime_serialize(Unit *unit, ExecRuntime *rt, FILE *f, FDSet *fds);
 330 int exec_runtime_deserialize_item(Unit *unit, ExecRuntime **rt, const char *key, const char *value, FDSet *fds);
 331
 332 void exec_runtime_destroy(ExecRuntime *rt);
 333
 334 const char* exec_output_to_string(ExecOutput i) _const_;
 335 ExecOutput exec_output_from_string(const char *s) _pure_;
 336
 337 const char* exec_input_to_string(ExecInput i) _const_;
 338 ExecInput exec_input_from_string(const char *s) _pure_;
 339
 340 const char* exec_utmp_mode_to_string(ExecUtmpMode i) _const_;
 341 ExecUtmpMode exec_utmp_mode_from_string(const char *s) _pure_;
 342
 343 const char* exec_preserve_mode_to_string(ExecPreserveMode i) _const_;
 344 ExecPreserveMode exec_preserve_mode_from_string(const char *s) _pure_;