src/lxc/conf.h

   1 /*
   2  * lxc: linux Container library
   3  *
   4  * (C) Copyright IBM Corp. 2007, 2008
   5  *
   6  * Authors:
   7  * Daniel Lezcano <daniel.lezcano at free.fr>
   8  *
   9  * This library is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public
  11  * License as published by the Free Software Foundation; either
  12  * version 2.1 of the License, or (at your option) any later version.
  13  *
  14  * This library is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with this library; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  22  */
  23 #ifndef __LXC_CONF_H
  24 #define __LXC_CONF_H
  25
  26 #include "config.h"
  27
  28 #include <stdio.h>
  29 #include <linux/magic.h>
  30 #include <net/if.h>
  31 #include <netinet/in.h>
  32 #include <sys/param.h>
  33 #include <sys/types.h>
  34 #include <stdbool.h>
  35 #include <sys/vfs.h>
  36
  37 #if HAVE_SYS_RESOURCE_H
  38 #include <sys/resource.h>
  39 #endif
  40
  41 #include "compiler.h"
  42 #include "list.h"
  43 #include "ringbuf.h"
  44 #include "start.h" /* for lxc_handler */
  45 #include "terminal.h"
  46
  47 #if HAVE_SCMP_FILTER_CTX
  48 typedef void * scmp_filter_ctx;
  49 #endif
  50
  51 /* worth moving to configure.ac? */
  52 #define subuidfile "/etc/subuid"
  53 #define subgidfile "/etc/subgid"
  54
  55 /*
  56  * Defines a generic struct to configure the control group. It is up to the
  57  * programmer to specify the right subsystem.
  58  * @subsystem : the targeted subsystem
  59  * @value     : the value to set
  60  * @version   : The version of the cgroup filesystem on which the controller
  61  *              resides.
  62  *
  63  * @controllers : The controllers to use for this container.
  64  * @dir         : The name of the directory containing the container's cgroup.
  65  *                Not that this is a per-container setting.
  66  */
  67 struct lxc_cgroup {
  68         union {
  69                 /* information about a specific controller */
  70                 struct /* controller */ {
  71                         int version;
  72                         char *subsystem;
  73                         char *value;
  74                 };
  75
  76                 /* meta information about cgroup configuration */
  77                 struct /* meta */ {
  78                         char *controllers;
  79                         char *dir;
  80                         bool keep;
  81                 };
  82         };
  83 };
  84
  85 #if !HAVE_SYS_RESOURCE_H
  86 #define RLIM_INFINITY ((unsigned long)-1)
  87 struct rlimit {
  88         unsigned long rlim_cur;
  89         unsigned long rlim_max;
  90 };
  91 #endif
  92
  93 /*
  94  * Defines a structure to configure resource limits to set via setrlimit().
  95  * @resource : the resource name in lowercase without the RLIMIT_ prefix
  96  * @limit    : the limit to set
  97  */
  98 struct lxc_limit {
  99         char *resource;
 100         struct rlimit limit;
 101 };
 102
 103 enum idtype {
 104         ID_TYPE_UID,
 105         ID_TYPE_GID
 106 };
 107
 108 /*
 109  * Defines a structure to configure kernel parameters at runtime.
 110  * @key      : the kernel parameters will be configured without the "lxc.sysctl" prefix
 111  * @value    : the value to set
 112  */
 113 struct lxc_sysctl {
 114         char *key;
 115         char *value;
 116 };
 117
 118 /*
 119  * Defines a structure to configure proc filesystem at runtime.
 120  * @filename : the proc filesystem will be configured without the "lxc.proc" prefix
 121  * @value    : the value to set
 122  */
 123 struct lxc_proc {
 124         char *filename;
 125         char *value;
 126 };
 127
 128 /*
 129  * id_map is an id map entry.  Form in confile is:
 130  * lxc.idmap = u 0    9800 100
 131  * lxc.idmap = u 1000 9900 100
 132  * lxc.idmap = g 0    9800 100
 133  * lxc.idmap = g 1000 9900 100
 134  * meaning the container can use uids and gids 0-99 and 1000-1099,
 135  * with [ug]id 0 mapping to [ug]id 9800 on the host, and [ug]id 1000 to
 136  * [ug]id 9900 on the host.
 137  */
 138 struct id_map {
 139         enum idtype idtype;
 140         unsigned long hostid, nsid, range;
 141 };
 142
 143 /* Defines the number of tty configured and contains the
 144  * instantiated ptys
 145  * @max = number of configured ttys
 146  */
 147 struct lxc_tty_info {
 148         size_t max;
 149         char *dir;
 150         char *tty_names;
 151         struct lxc_terminal_info *tty;
 152 };
 153
 154 /* Defines a structure to store the rootfs location, the
 155  * optionals pivot_root, rootfs mount paths
 156  * @path       : the rootfs source (directory or device)
 157  * @mount      : where it is mounted
 158  * @bev_type   : optional backing store type
 159  * @options    : mount options
 160  * @mountflags : the portion of @options that are flags
 161  * @data       : the porition of @options that are not flags
 162  */
 163 struct lxc_rootfs {
 164         char *path;
 165         char *mount;
 166         char *bdev_type;
 167         char *options;
 168         unsigned long mountflags;
 169         char *data;
 170 };
 171
 172 /*
 173  * Automatic mounts for LXC to perform inside the container
 174  */
 175 enum {
 176         LXC_AUTO_PROC_RW              = 0x001, /* /proc read-write */
 177         LXC_AUTO_PROC_MIXED           = 0x002, /* /proc/sys and /proc/sysrq-trigger read-only */
 178         LXC_AUTO_PROC_MASK            = 0x003,
 179
 180         LXC_AUTO_SYS_RW               = 0x004, /* /sys */
 181         LXC_AUTO_SYS_RO               = 0x008, /* /sys read-only */
 182         LXC_AUTO_SYS_MIXED            = 0x00C, /* /sys read-only and /sys/class/net read-write */
 183         LXC_AUTO_SYS_MASK             = 0x00C,
 184
 185         LXC_AUTO_CGROUP_RO            = 0x010, /* /sys/fs/cgroup (partial mount, read-only) */
 186         LXC_AUTO_CGROUP_RW            = 0x020, /* /sys/fs/cgroup (partial mount, read-write) */
 187         LXC_AUTO_CGROUP_MIXED         = 0x030, /* /sys/fs/cgroup (partial mount, paths r/o, cgroup r/w) */
 188         LXC_AUTO_CGROUP_FULL_RO       = 0x040, /* /sys/fs/cgroup (full mount, read-only) */
 189         LXC_AUTO_CGROUP_FULL_RW       = 0x050, /* /sys/fs/cgroup (full mount, read-write) */
 190         LXC_AUTO_CGROUP_FULL_MIXED    = 0x060, /* /sys/fs/cgroup (full mount, parent r/o, own r/w) */
 191         /*
 192          * These are defined in such a way as to retain binary compatibility
 193          * with earlier versions of this code. If the previous mask is applied,
 194          * both of these will default back to the _MIXED variants, which is
 195          * safe.
 196          */
 197         LXC_AUTO_CGROUP_NOSPEC        = 0x0B0, /* /sys/fs/cgroup (partial mount, r/w or mixed, depending on caps) */
 198         LXC_AUTO_CGROUP_FULL_NOSPEC   = 0x0E0, /* /sys/fs/cgroup (full mount, r/w or mixed, depending on caps) */
 199         LXC_AUTO_CGROUP_FORCE         = 0x100, /* mount cgroups even when cgroup namespaces are supported */
 200         LXC_AUTO_CGROUP_MASK          = 0x1F0, /* all known cgroup options, doe not contain LXC_AUTO_CGROUP_FORCE */
 201
 202         LXC_AUTO_SHMOUNTS             = 0x200, /* shared mount point */
 203         LXC_AUTO_SHMOUNTS_MASK        = 0x200, /* shared mount point mask */
 204         LXC_AUTO_ALL_MASK             = 0x1FF, /* all known settings */
 205 };
 206
 207 enum lxchooks {
 208         LXCHOOK_PRESTART,
 209         LXCHOOK_PREMOUNT,
 210         LXCHOOK_MOUNT,
 211         LXCHOOK_AUTODEV,
 212         LXCHOOK_START,
 213         LXCHOOK_STOP,
 214         LXCHOOK_POSTSTOP,
 215         LXCHOOK_CLONE,
 216         LXCHOOK_DESTROY,
 217         LXCHOOK_START_HOST,
 218         NUM_LXC_HOOKS
 219 };
 220
 221 extern char *lxchook_names[NUM_LXC_HOOKS];
 222
 223 struct lxc_state_client {
 224         int clientfd;
 225         lxc_state_t states[MAX_STATE];
 226 };
 227
 228 struct lxc_conf {
 229         /* Pointer to the name of the container. Do not free! */
 230         const char *name;
 231         bool is_execute;
 232         int reboot;
 233         signed long personality;
 234         struct utsname *utsname;
 235
 236         struct {
 237                 struct lxc_list cgroup;
 238                 struct lxc_list cgroup2;
 239         };
 240
 241         struct {
 242                 struct lxc_list id_map;
 243
 244                 /*
 245                  * Pointer to the idmap entry for the container's root uid in
 246                  * the id_map list. Do not free!
 247                  */
 248                 const struct id_map *root_nsuid_map;
 249
 250                 /*
 251                  * Pointer to the idmap entry for the container's root gid in
 252                  * the id_map list. Do not free!
 253                  */
 254                 const struct id_map *root_nsgid_map;
 255         };
 256
 257         struct lxc_list network;
 258
 259         struct {
 260                 char *fstab;
 261                 int auto_mounts;
 262                 struct lxc_list mount_list;
 263         };
 264
 265         struct lxc_list caps;
 266         struct lxc_list keepcaps;
 267
 268         /* /dev/tty<idx> devices */
 269         struct lxc_tty_info ttys;
 270         /* /dev/console device */
 271         struct lxc_terminal console;
 272         /* maximum pty devices allowed by devpts mount */
 273         size_t pty_max;
 274
 275         /* set to true when rootfs has been setup */
 276         bool rootfs_setup;
 277         struct lxc_rootfs rootfs;
 278
 279         bool close_all_fds;
 280
 281         struct {
 282                 unsigned int hooks_version;
 283                 struct lxc_list hooks[NUM_LXC_HOOKS];
 284         };
 285
 286         char *lsm_aa_profile;
 287         char *lsm_aa_profile_computed;
 288         bool lsm_aa_profile_created;
 289         unsigned int lsm_aa_allow_nesting;
 290         unsigned int lsm_aa_allow_incomplete;
 291         struct lxc_list lsm_aa_raw;
 292         char *lsm_se_context;
 293         bool tmp_umount_proc;
 294         char *seccomp;  /* filename with the seccomp rules */
 295 #if HAVE_SCMP_FILTER_CTX
 296         scmp_filter_ctx seccomp_ctx;
 297 #endif
 298         int maincmd_fd;
 299         unsigned int autodev;  /* if 1, mount and fill a /dev at start */
 300         int haltsignal; /* signal used to halt container */
 301         int rebootsignal; /* signal used to reboot container */
 302         int stopsignal; /* signal used to hard stop container */
 303         char *rcfile;   /* Copy of the top level rcfile we read */
 304
 305         /* Logfile and logleve can be set in a container config file. Those
 306          * function as defaults. The defaults can be overriden by command line.
 307          * However we don't want the command line specified values to be saved
 308          * on c->save_config(). So we store the config file specified values
 309          * here. */
 310         char *logfile; /* the logfile as specifed in config */
 311         int loglevel; /* loglevel as specifed in config (if any) */
 312         int logfd;
 313
 314         unsigned int start_auto;
 315         unsigned int start_delay;
 316         int start_order;
 317         struct lxc_list groups;
 318         int nbd_idx;
 319
 320         /* unshare the mount namespace in the monitor */
 321         unsigned int monitor_unshare;
 322         unsigned int monitor_signal_pdeath;
 323
 324         /* list of included files */
 325         struct lxc_list includes;
 326         /* config entries which are not "lxc.*" are aliens */
 327         struct lxc_list aliens;
 328
 329         /* list of environment variables we'll add to the container when
 330          * started */
 331         struct lxc_list environment;
 332
 333         /* text representation of the config file */
 334         char *unexpanded_config;
 335         size_t unexpanded_len;
 336         size_t unexpanded_alloced;
 337
 338         /* default command for lxc-execute */
 339         char *execute_cmd;
 340
 341         /* init command */
 342         char *init_cmd;
 343
 344         /* if running in a new user namespace, the UID/GID that init and COMMAND
 345          * should run under when using lxc-execute */
 346         uid_t init_uid;
 347         gid_t init_gid;
 348
 349         /* indicator if the container will be destroyed on shutdown */
 350         unsigned int ephemeral;
 351
 352         /* The facility to pass to syslog. Let's users establish as what type of
 353          * program liblxc is supposed to write to the syslog. */
 354         char *syslog;
 355
 356         /* Whether PR_SET_NO_NEW_PRIVS will be set for the container. */
 357         bool no_new_privs;
 358
 359         /* RLIMIT_* limits */
 360         struct lxc_list limits;
 361
 362         /* Contains generic info about the cgroup configuration for this
 363          * container. Note that struct lxc_cgroup contains a union. It is only
 364          * valid to access the members of the anonymous "meta" struct within
 365          * that union.
 366          */
 367         struct lxc_cgroup cgroup_meta;
 368
 369         struct {
 370                 int ns_clone;
 371                 int ns_keep;
 372                 char *ns_share[LXC_NS_MAX];
 373         };
 374
 375         /* init working directory */
 376         char *init_cwd;
 377
 378         /* A list of clients registered to be informed about a container state. */
 379         struct lxc_list state_clients;
 380
 381         /* sysctls */
 382         struct lxc_list sysctls;
 383
 384         /* procs */
 385         struct lxc_list procs;
 386
 387         struct shmount {
 388                 /* Absolute path to the shared mount point on the host */
 389                 char *path_host;
 390                 /* Absolute path (in the container) to the shared mount point */
 391                 char *path_cont;
 392         } shmount;
 393 };
 394
 395 extern int write_id_mapping(enum idtype idtype, pid_t pid, const char *buf,
 396                             size_t buf_size);
 397
 398 #ifdef HAVE_TLS
 399 extern thread_local struct lxc_conf *current_config;
 400 #else
 401 extern struct lxc_conf *current_config;
 402 #endif
 403
 404 extern int run_lxc_hooks(const char *name, char *hook, struct lxc_conf *conf,
 405                          char *argv[]);
 406 extern int detect_shared_rootfs(void);
 407 extern struct lxc_conf *lxc_conf_init(void);
 408 extern void lxc_conf_free(struct lxc_conf *conf);
 409 extern int pin_rootfs(const char *rootfs);
 410 extern int lxc_map_ids(struct lxc_list *idmap, pid_t pid);
 411 extern int lxc_create_tty(const char *name, struct lxc_conf *conf);
 412 extern void lxc_delete_tty(struct lxc_tty_info *ttys);
 413 extern int lxc_clear_config_caps(struct lxc_conf *c);
 414 extern int lxc_clear_config_keepcaps(struct lxc_conf *c);
 415 extern int lxc_clear_cgroups(struct lxc_conf *c, const char *key, int version);
 416 extern int lxc_clear_mount_entries(struct lxc_conf *c);
 417 extern int lxc_clear_automounts(struct lxc_conf *c);
 418 extern int lxc_clear_hooks(struct lxc_conf *c, const char *key);
 419 extern int lxc_clear_idmaps(struct lxc_conf *c);
 420 extern int lxc_clear_groups(struct lxc_conf *c);
 421 extern int lxc_clear_environment(struct lxc_conf *c);
 422 extern int lxc_clear_limits(struct lxc_conf *c, const char *key);
 423 extern int lxc_delete_autodev(struct lxc_handler *handler);
 424 extern void lxc_clear_includes(struct lxc_conf *conf);
 425 extern int lxc_setup_rootfs_prepare_root(struct lxc_conf *conf,
 426                                          const char *name, const char *lxcpath);
 427 extern int lxc_setup(struct lxc_handler *handler);
 428 extern int lxc_setup_parent(struct lxc_handler *handler);
 429 extern int setup_resource_limits(struct lxc_list *limits, pid_t pid);
 430 extern int find_unmapped_nsid(struct lxc_conf *conf, enum idtype idtype);
 431 extern int mapped_hostid(unsigned id, struct lxc_conf *conf,
 432                          enum idtype idtype);
 433 extern int chown_mapped_root(const char *path, struct lxc_conf *conf);
 434 extern int userns_exec_1(struct lxc_conf *conf, int (*fn)(void *), void *data,
 435                          const char *fn_name);
 436 extern int userns_exec_full(struct lxc_conf *conf, int (*fn)(void *),
 437                             void *data, const char *fn_name);
 438 extern int parse_mntopts(const char *mntopts, unsigned long *mntflags,
 439                          char **mntdata);
 440 extern int parse_propagationopts(const char *mntopts, unsigned long *pflags);
 441 extern void tmp_proc_unmount(struct lxc_conf *lxc_conf);
 442 extern void remount_all_slave(void);
 443 extern void suggest_default_idmap(void);
 444 extern FILE *make_anonymous_mount_file(struct lxc_list *mount,
 445                                        bool include_nesting_helpers);
 446 extern struct lxc_list *sort_cgroup_settings(struct lxc_list *cgroup_settings);
 447 extern unsigned long add_required_remount_flags(const char *s, const char *d,
 448                                                 unsigned long flags);
 449 extern int run_script(const char *name, const char *section, const char *script,
 450                       ...);
 451 extern int run_script_argv(const char *name, unsigned int hook_version,
 452                            const char *section, const char *script,
 453                            const char *hookname, char **argsin);
 454 extern int in_caplist(int cap, struct lxc_list *caps);
 455 extern int setup_sysctl_parameters(struct lxc_list *sysctls);
 456 extern int lxc_clear_sysctls(struct lxc_conf *c, const char *key);
 457 extern int setup_proc_filesystem(struct lxc_list *procs, pid_t pid);
 458 extern int lxc_clear_procs(struct lxc_conf *c, const char *key);
 459 extern int lxc_clear_apparmor_raw(struct lxc_conf *c);
 460
 461 #endif /* __LXC_CONF_H */