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 struct ExecStatus {
  76         dual_timestamp start_timestamp;
  77         dual_timestamp exit_timestamp;
  78         pid_t pid;
  79         int code;     /* as in siginfo_t::si_code */
  80         int status;   /* as in sigingo_t::si_status */
  81 };
  82
  83 struct ExecCommand {
  84         char *path;
  85         char **argv;
  86         ExecStatus exec_status;
  87         LIST_FIELDS(ExecCommand, command); /* useful for chaining commands */
  88         bool ignore:1;
  89         bool privileged:1;
  90 };
  91
  92 struct ExecRuntime {
  93         int n_ref;
  94
  95         char *tmp_dir;
  96         char *var_tmp_dir;
  97
  98         /* An AF_UNIX socket pair, that contains a datagram containing a file descriptor referring to the network
  99          * namespace. */
 100         int netns_storage_socket[2];
 101 };
 102
 103 struct ExecContext {
 104         char **environment;
 105         char **environment_files;
 106         char **pass_environment;
 107
 108         struct rlimit *rlimit[_RLIMIT_MAX];
 109         char *working_directory, *root_directory, *root_image;
 110         bool working_directory_missing_ok;
 111         bool working_directory_home;
 112
 113         mode_t umask;
 114         int oom_score_adjust;
 115         int nice;
 116         int ioprio;
 117         int cpu_sched_policy;
 118         int cpu_sched_priority;
 119
 120         cpu_set_t *cpuset;
 121         unsigned cpuset_ncpus;
 122
 123         ExecInput std_input;
 124         ExecOutput std_output;
 125         ExecOutput std_error;
 126         char *stdio_fdname[3];
 127
 128         nsec_t timer_slack_nsec;
 129
 130         bool stdio_as_fds;
 131
 132         char *tty_path;
 133
 134         bool tty_reset;
 135         bool tty_vhangup;
 136         bool tty_vt_disallocate;
 137
 138         bool ignore_sigpipe;
 139
 140         /* Since resolving these names might involve socket
 141          * connections and we don't want to deadlock ourselves these
 142          * names are resolved on execution only and in the child
 143          * process. */
 144         char *user;
 145         char *group;
 146         char **supplementary_groups;
 147
 148         char *pam_name;
 149
 150         char *utmp_id;
 151         ExecUtmpMode utmp_mode;
 152
 153         bool selinux_context_ignore;
 154         char *selinux_context;
 155
 156         bool apparmor_profile_ignore;
 157         char *apparmor_profile;
 158
 159         bool smack_process_label_ignore;
 160         char *smack_process_label;
 161
 162         char **read_write_paths, **read_only_paths, **inaccessible_paths;
 163         unsigned long mount_flags;
 164         BindMount *bind_mounts;
 165         unsigned n_bind_mounts;
 166
 167         uint64_t capability_bounding_set;
 168         uint64_t capability_ambient_set;
 169         int secure_bits;
 170
 171         int syslog_priority;
 172         char *syslog_identifier;
 173         bool syslog_level_prefix;
 174
 175         bool cpu_sched_reset_on_fork;
 176         bool non_blocking;
 177         bool private_tmp;
 178         bool private_network;
 179         bool private_devices;
 180         bool private_users;
 181         ProtectSystem protect_system;
 182         ProtectHome protect_home;
 183         bool protect_kernel_tunables;
 184         bool protect_kernel_modules;
 185         bool protect_control_groups;
 186         bool mount_apivfs;
 187
 188         bool no_new_privileges;
 189
 190         bool dynamic_user;
 191         bool remove_ipc;
 192
 193         /* This is not exposed to the user but available
 194          * internally. We need it to make sure that whenever we spawn
 195          * /usr/bin/mount it is run in the same process group as us so
 196          * that the autofs logic detects that it belongs to us and we
 197          * don't enter a trigger loop. */
 198         bool same_pgrp;
 199
 200         unsigned long personality;
 201
 202         unsigned long restrict_namespaces; /* The CLONE_NEWxyz flags permitted to the unit's processes */
 203
 204         Set *syscall_filter;
 205         Set *syscall_archs;
 206         int syscall_errno;
 207         bool syscall_whitelist:1;
 208
 209         Set *address_families;
 210         bool address_families_whitelist:1;
 211
 212         char **runtime_directory;
 213         mode_t runtime_directory_mode;
 214
 215         bool memory_deny_write_execute;
 216         bool restrict_realtime;
 217
 218         bool oom_score_adjust_set:1;
 219         bool nice_set:1;
 220         bool ioprio_set:1;
 221         bool cpu_sched_set:1;
 222 };
 223
 224 static inline bool exec_context_restrict_namespaces_set(const ExecContext *c) {
 225         assert(c);
 226
 227         return (c->restrict_namespaces & NAMESPACE_FLAGS_ALL) != NAMESPACE_FLAGS_ALL;
 228 }
 229
 230 typedef enum ExecFlags {
 231         EXEC_APPLY_PERMISSIONS = 1U << 0,
 232         EXEC_APPLY_CHROOT      = 1U << 1,
 233         EXEC_APPLY_TTY_STDIN   = 1U << 2,
 234         EXEC_NEW_KEYRING       = 1U << 3,
 235
 236         /* The following are not used by execute.c, but by consumers internally */
 237         EXEC_PASS_FDS          = 1U << 4,
 238         EXEC_IS_CONTROL        = 1U << 5,
 239         EXEC_SETENV_RESULT     = 1U << 6,
 240         EXEC_SET_WATCHDOG      = 1U << 7,
 241 } ExecFlags;
 242
 243 struct ExecParameters {
 244         char **argv;
 245         char **environment;
 246
 247         int *fds;
 248         char **fd_names;
 249         unsigned n_fds;
 250
 251         ExecFlags flags;
 252         bool selinux_context_net:1;
 253
 254         bool cgroup_delegate:1;
 255         CGroupMask cgroup_supported;
 256         const char *cgroup_path;
 257
 258         const char *runtime_prefix;
 259
 260         const char *confirm_spawn;
 261
 262         usec_t watchdog_usec;
 263
 264         int *idle_pipe;
 265
 266         int stdin_fd;
 267         int stdout_fd;
 268         int stderr_fd;
 269 };
 270
 271 #include "unit.h"
 272 #include "dynamic-user.h"
 273
 274 int exec_spawn(Unit *unit,
 275                ExecCommand *command,
 276                const ExecContext *context,
 277                const ExecParameters *exec_params,
 278                ExecRuntime *runtime,
 279                DynamicCreds *dynamic_creds,
 280                pid_t *ret);
 281
 282 void exec_command_done(ExecCommand *c);
 283 void exec_command_done_array(ExecCommand *c, unsigned n);
 284
 285 ExecCommand* exec_command_free_list(ExecCommand *c);
 286 void exec_command_free_array(ExecCommand **c, unsigned n);
 287
 288 char *exec_command_line(char **argv);
 289
 290 void exec_command_dump(ExecCommand *c, FILE *f, const char *prefix);
 291 void exec_command_dump_list(ExecCommand *c, FILE *f, const char *prefix);
 292 void exec_command_append_list(ExecCommand **l, ExecCommand *e);
 293 int exec_command_set(ExecCommand *c, const char *path, ...);
 294 int exec_command_append(ExecCommand *c, const char *path, ...);
 295
 296 void exec_context_init(ExecContext *c);
 297 void exec_context_done(ExecContext *c);
 298 void exec_context_dump(ExecContext *c, FILE* f, const char *prefix);
 299
 300 int exec_context_destroy_runtime_directory(ExecContext *c, const char *runtime_root);
 301
 302 int exec_context_load_environment(Unit *unit, const ExecContext *c, char ***l);
 303 int exec_context_named_iofds(Unit *unit, const ExecContext *c, const ExecParameters *p, int named_iofds[3]);
 304 const char* exec_context_fdname(const ExecContext *c, int fd_index);
 305
 306 bool exec_context_may_touch_console(ExecContext *c);
 307 bool exec_context_maintains_privileges(ExecContext *c);
 308
 309 void exec_status_start(ExecStatus *s, pid_t pid);
 310 void exec_status_exit(ExecStatus *s, ExecContext *context, pid_t pid, int code, int status);
 311 void exec_status_dump(ExecStatus *s, FILE *f, const char *prefix);
 312
 313 int exec_runtime_make(ExecRuntime **rt, ExecContext *c, const char *id);
 314 ExecRuntime *exec_runtime_ref(ExecRuntime *r);
 315 ExecRuntime *exec_runtime_unref(ExecRuntime *r);
 316
 317 int exec_runtime_serialize(Unit *unit, ExecRuntime *rt, FILE *f, FDSet *fds);
 318 int exec_runtime_deserialize_item(Unit *unit, ExecRuntime **rt, const char *key, const char *value, FDSet *fds);
 319
 320 void exec_runtime_destroy(ExecRuntime *rt);
 321
 322 const char* exec_output_to_string(ExecOutput i) _const_;
 323 ExecOutput exec_output_from_string(const char *s) _pure_;
 324
 325 const char* exec_input_to_string(ExecInput i) _const_;
 326 ExecInput exec_input_from_string(const char *s) _pure_;
 327
 328 const char* exec_utmp_mode_to_string(ExecUtmpMode i) _const_;
 329 ExecUtmpMode exec_utmp_mode_from_string(const char *s) _pure_;