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;
 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
 165         uint64_t capability_bounding_set;
 166         uint64_t capability_ambient_set;
 167         int secure_bits;
 168
 169         int syslog_priority;
 170         char *syslog_identifier;
 171         bool syslog_level_prefix;
 172
 173         bool cpu_sched_reset_on_fork;
 174         bool non_blocking;
 175         bool private_tmp;
 176         bool private_network;
 177         bool private_devices;
 178         bool private_users;
 179         ProtectSystem protect_system;
 180         ProtectHome protect_home;
 181         bool protect_kernel_tunables;
 182         bool protect_kernel_modules;
 183         bool protect_control_groups;
 184
 185         bool no_new_privileges;
 186
 187         bool dynamic_user;
 188         bool remove_ipc;
 189
 190         /* This is not exposed to the user but available
 191          * internally. We need it to make sure that whenever we spawn
 192          * /usr/bin/mount it is run in the same process group as us so
 193          * that the autofs logic detects that it belongs to us and we
 194          * don't enter a trigger loop. */
 195         bool same_pgrp;
 196
 197         unsigned long personality;
 198
 199         unsigned long restrict_namespaces; /* The CLONE_NEWxyz flags permitted to the unit's processes */
 200
 201         Set *syscall_filter;
 202         Set *syscall_archs;
 203         int syscall_errno;
 204         bool syscall_whitelist:1;
 205
 206         Set *address_families;
 207         bool address_families_whitelist:1;
 208
 209         char **runtime_directory;
 210         mode_t runtime_directory_mode;
 211
 212         bool memory_deny_write_execute;
 213         bool restrict_realtime;
 214
 215         bool oom_score_adjust_set:1;
 216         bool nice_set:1;
 217         bool ioprio_set:1;
 218         bool cpu_sched_set:1;
 219 };
 220
 221 static inline bool exec_context_restrict_namespaces_set(const ExecContext *c) {
 222         assert(c);
 223
 224         return (c->restrict_namespaces & NAMESPACE_FLAGS_ALL) != NAMESPACE_FLAGS_ALL;
 225 }
 226
 227 typedef enum ExecFlags {
 228         EXEC_APPLY_PERMISSIONS = 1U << 0,
 229         EXEC_APPLY_CHROOT      = 1U << 1,
 230         EXEC_APPLY_TTY_STDIN   = 1U << 2,
 231
 232         /* The following are not used by execute.c, but by consumers internally */
 233         EXEC_PASS_FDS          = 1U << 3,
 234         EXEC_IS_CONTROL        = 1U << 4,
 235         EXEC_SETENV_RESULT     = 1U << 5,
 236         EXEC_SET_WATCHDOG      = 1U << 6,
 237 } ExecFlags;
 238
 239 struct ExecParameters {
 240         char **argv;
 241         char **environment;
 242
 243         int *fds;
 244         char **fd_names;
 245         unsigned n_fds;
 246
 247         ExecFlags flags;
 248         bool selinux_context_net:1;
 249
 250         bool cgroup_delegate:1;
 251         CGroupMask cgroup_supported;
 252         const char *cgroup_path;
 253
 254         const char *runtime_prefix;
 255
 256         const char *confirm_spawn;
 257
 258         usec_t watchdog_usec;
 259
 260         int *idle_pipe;
 261
 262         int stdin_fd;
 263         int stdout_fd;
 264         int stderr_fd;
 265 };
 266
 267 #include "unit.h"
 268 #include "dynamic-user.h"
 269
 270 int exec_spawn(Unit *unit,
 271                ExecCommand *command,
 272                const ExecContext *context,
 273                const ExecParameters *exec_params,
 274                ExecRuntime *runtime,
 275                DynamicCreds *dynamic_creds,
 276                pid_t *ret);
 277
 278 void exec_command_done(ExecCommand *c);
 279 void exec_command_done_array(ExecCommand *c, unsigned n);
 280
 281 ExecCommand* exec_command_free_list(ExecCommand *c);
 282 void exec_command_free_array(ExecCommand **c, unsigned n);
 283
 284 char *exec_command_line(char **argv);
 285
 286 void exec_command_dump(ExecCommand *c, FILE *f, const char *prefix);
 287 void exec_command_dump_list(ExecCommand *c, FILE *f, const char *prefix);
 288 void exec_command_append_list(ExecCommand **l, ExecCommand *e);
 289 int exec_command_set(ExecCommand *c, const char *path, ...);
 290 int exec_command_append(ExecCommand *c, const char *path, ...);
 291
 292 void exec_context_init(ExecContext *c);
 293 void exec_context_done(ExecContext *c);
 294 void exec_context_dump(ExecContext *c, FILE* f, const char *prefix);
 295
 296 int exec_context_destroy_runtime_directory(ExecContext *c, const char *runtime_root);
 297
 298 int exec_context_load_environment(Unit *unit, const ExecContext *c, char ***l);
 299 int exec_context_named_iofds(Unit *unit, const ExecContext *c, const ExecParameters *p, int named_iofds[3]);
 300 const char* exec_context_fdname(const ExecContext *c, int fd_index);
 301
 302 bool exec_context_may_touch_console(ExecContext *c);
 303 bool exec_context_maintains_privileges(ExecContext *c);
 304
 305 void exec_status_start(ExecStatus *s, pid_t pid);
 306 void exec_status_exit(ExecStatus *s, ExecContext *context, pid_t pid, int code, int status);
 307 void exec_status_dump(ExecStatus *s, FILE *f, const char *prefix);
 308
 309 int exec_runtime_make(ExecRuntime **rt, ExecContext *c, const char *id);
 310 ExecRuntime *exec_runtime_ref(ExecRuntime *r);
 311 ExecRuntime *exec_runtime_unref(ExecRuntime *r);
 312
 313 int exec_runtime_serialize(Unit *unit, ExecRuntime *rt, FILE *f, FDSet *fds);
 314 int exec_runtime_deserialize_item(Unit *unit, ExecRuntime **rt, const char *key, const char *value, FDSet *fds);
 315
 316 void exec_runtime_destroy(ExecRuntime *rt);
 317
 318 const char* exec_output_to_string(ExecOutput i) _const_;
 319 ExecOutput exec_output_from_string(const char *s) _pure_;
 320
 321 const char* exec_input_to_string(ExecInput i) _const_;
 322 ExecInput exec_input_from_string(const char *s) _pure_;
 323
 324 const char* exec_utmp_mode_to_string(ExecUtmpMode i) _const_;
 325 ExecUtmpMode exec_utmp_mode_from_string(const char *s) _pure_;