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