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