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
  42 #if HAVE_SCMP_FILTER_CTX
  43 typedef void * scmp_filter_ctx;
  44 #endif
  45
  46 /* worth moving to configure.ac? */
  47 #define subuidfile "/etc/subuid"
  48 #define subgidfile "/etc/subgid"
  49
  50 /*
  51  * Defines a generic struct to configure the control group. It is up to the
  52  * programmer to specify the right subsystem.
  53  * @subsystem : the targeted subsystem
  54  * @value     : the value to set
  55  *
  56  * @controllers : The controllers to use for this container.
  57  * @dir         : The name of the directory containing the container's cgroup.
  58  *                Not that this is a per-container setting.
  59  */
  60 struct lxc_cgroup {
  61         union {
  62                 /* information about a specific controller */
  63                 struct /* controller */ {
  64                         char *subsystem;
  65                         char *value;
  66                 };
  67
  68                 /* meta information about cgroup configuration */
  69                 struct /* meta */ {
  70                         char *controllers;
  71                         char *dir;
  72                 };
  73         };
  74 };
  75
  76 #if !HAVE_SYS_RESOURCE_H
  77 # define RLIM_INFINITY ((unsigned long)-1)
  78 struct rlimit {
  79         unsigned long rlim_cur;
  80         unsigned long rlim_max;
  81 };
  82 #endif
  83 /*
  84  * Defines a structure to configure resource limits to set via setrlimit().
  85  * @resource : the resource name in lowercase without the RLIMIT_ prefix
  86  * @limit    : the limit to set
  87  */
  88 struct lxc_limit {
  89         char *resource;
  90         struct rlimit limit;
  91 };
  92
  93 enum idtype {
  94         ID_TYPE_UID,
  95         ID_TYPE_GID
  96 };
  97
  98 /*
  99  * Defines a structure to configure kernel parameters at runtime.
 100  * @key      : the kernel parameters will be configured without the "lxc.sysctl" prefix
 101  * @value    : the value to set
 102  */
 103 struct lxc_sysctl {
 104         char *key;
 105         char *value;
 106 };
 107
 108 /*
 109  * Defines a structure to configure proc filesystem at runtime.
 110  * @filename : the proc filesystem will be configured without the "lxc.proc" prefix
 111  * @value    : the value to set
 112  */
 113 struct lxc_proc {
 114         char *filename;
 115         char *value;
 116 };
 117
 118 /*
 119  * id_map is an id map entry.  Form in confile is:
 120  * lxc.idmap = u 0    9800 100
 121  * lxc.idmap = u 1000 9900 100
 122  * lxc.idmap = g 0    9800 100
 123  * lxc.idmap = g 1000 9900 100
 124  * meaning the container can use uids and gids 0-99 and 1000-1099,
 125  * with [ug]id 0 mapping to [ug]id 9800 on the host, and [ug]id 1000 to
 126  * [ug]id 9900 on the host.
 127  */
 128 struct id_map {
 129         enum idtype idtype;
 130         unsigned long hostid, nsid, range;
 131 };
 132
 133 /*
 134  * Defines a structure containing a pty information for
 135  * virtualizing a tty
 136  * @name   : the path name of the slave pty side
 137  * @master : the file descriptor of the master
 138  * @slave  : the file descriptor of the slave
 139  */
 140 struct lxc_pty_info {
 141         char name[MAXPATHLEN];
 142         int master;
 143         int slave;
 144         int busy;
 145 };
 146
 147 /*
 148  * Defines the number of tty configured and contains the
 149  * instantiated ptys
 150  * @nbtty = number of configured ttys
 151  */
 152 struct lxc_tty_info {
 153         int nbtty;
 154         struct lxc_pty_info *pty_info;
 155 };
 156
 157 struct lxc_tty_state;
 158
 159 /*
 160  * Defines the structure to store the console information
 161  * @peer   : the file descriptor put/get console traffic
 162  * @name   : the file name of the slave pty
 163  */
 164 struct lxc_console {
 165         int slave;
 166         int master;
 167         int peer;
 168         struct lxc_pty_info peerpty;
 169         struct lxc_epoll_descr *descr;
 170         char *path;
 171         char *log_path;
 172         int log_fd;
 173         unsigned int log_rotate;
 174         char name[MAXPATHLEN];
 175         struct termios *tios;
 176         struct lxc_tty_state *tty_state;
 177
 178         /* size of the ringbuffer */
 179         uint64_t buffer_size;
 180
 181         /* path to the log file for the ringbuffer */
 182         char *buffer_log_file;
 183
 184         /* fd to the log file for the ringbuffer */
 185         int buffer_log_file_fd;
 186
 187         /* the in-memory ringbuffer */
 188         struct lxc_ringbuf ringbuf;
 189 };
 190
 191 /*
 192  * Defines a structure to store the rootfs location, the
 193  * optionals pivot_root, rootfs mount paths
 194  * @path       : the rootfs source (directory or device)
 195  * @mount      : where it is mounted
 196  * @options    : mount options
 197  * @bev_type   : optional backing store type
 198  */
 199 struct lxc_rootfs {
 200         char *path;
 201         char *mount;
 202         char *options;
 203         char *bdev_type;
 204 };
 205
 206 /*
 207  * Automatic mounts for LXC to perform inside the container
 208  */
 209 enum {
 210         LXC_AUTO_PROC_RW              = 0x001,   /* /proc read-write */
 211         LXC_AUTO_PROC_MIXED           = 0x002,   /* /proc/sys and /proc/sysrq-trigger read-only */
 212         LXC_AUTO_PROC_MASK            = 0x003,
 213
 214         LXC_AUTO_SYS_RW               = 0x004,   /* /sys */
 215         LXC_AUTO_SYS_RO               = 0x008,   /* /sys read-only */
 216         LXC_AUTO_SYS_MIXED            = 0x00C,   /* /sys read-only and /sys/class/net read-write */
 217         LXC_AUTO_SYS_MASK             = 0x00C,
 218
 219         LXC_AUTO_CGROUP_RO            = 0x010,   /* /sys/fs/cgroup (partial mount, read-only) */
 220         LXC_AUTO_CGROUP_RW            = 0x020,   /* /sys/fs/cgroup (partial mount, read-write) */
 221         LXC_AUTO_CGROUP_MIXED         = 0x030,   /* /sys/fs/cgroup (partial mount, paths r/o, cgroup r/w) */
 222         LXC_AUTO_CGROUP_FULL_RO       = 0x040,   /* /sys/fs/cgroup (full mount, read-only) */
 223         LXC_AUTO_CGROUP_FULL_RW       = 0x050,   /* /sys/fs/cgroup (full mount, read-write) */
 224         LXC_AUTO_CGROUP_FULL_MIXED    = 0x060,   /* /sys/fs/cgroup (full mount, parent r/o, own r/w) */
 225         /* These are defined in such a way as to retain
 226          * binary compatibility with earlier versions of
 227          * this code. If the previous mask is applied,
 228          * both of these will default back to the _MIXED
 229          * variants, which is safe. */
 230         LXC_AUTO_CGROUP_NOSPEC        = 0x0B0,   /* /sys/fs/cgroup (partial mount, r/w or mixed, depending on caps) */
 231         LXC_AUTO_CGROUP_FULL_NOSPEC   = 0x0E0,   /* /sys/fs/cgroup (full mount, r/w or mixed, depending on caps) */
 232         LXC_AUTO_CGROUP_MASK          = 0x0F0,
 233
 234         LXC_AUTO_ALL_MASK             = 0x0FF,   /* all known settings */
 235 };
 236
 237 /*
 238  * Defines the global container configuration
 239  * @rootfs     : root directory to run the container
 240  * @mount      : list of mount points
 241  * @tty        : numbers of tty
 242  * @pts        : new pts instance
 243  * @mount_list : list of mount point (alternative to fstab file)
 244  * @network    : network configuration
 245  * @utsname    : container utsname
 246  * @fstab      : path to a fstab file format
 247  * @caps       : list of the capabilities to drop
 248  * @keepcaps   : list of the capabilities to keep
 249  * @tty_info   : tty data
 250  * @console    : console data
 251  * @ttydir     : directory (under /dev) in which to create console and ttys
 252  * @lsm_aa_profile : apparmor profile to switch to or NULL
 253  * @lsm_se_context : selinux type to switch to or NULL
 254  */
 255 enum lxchooks {
 256         LXCHOOK_PRESTART,
 257         LXCHOOK_PREMOUNT,
 258         LXCHOOK_MOUNT,
 259         LXCHOOK_AUTODEV,
 260         LXCHOOK_START,
 261         LXCHOOK_STOP,
 262         LXCHOOK_POSTSTOP,
 263         LXCHOOK_CLONE,
 264         LXCHOOK_DESTROY,
 265         LXCHOOK_START_HOST,
 266         NUM_LXC_HOOKS
 267 };
 268
 269 extern char *lxchook_names[NUM_LXC_HOOKS];
 270
 271 struct lxc_state_client {
 272         int clientfd;
 273         lxc_state_t states[MAX_STATE];
 274 };
 275
 276 struct lxc_conf {
 277         int is_execute;
 278         char *fstab;
 279         unsigned int tty;
 280         unsigned int pts;
 281         int reboot;
 282         signed long personality;
 283         struct utsname *utsname;
 284         struct lxc_list cgroup;
 285         struct {
 286                 struct lxc_list id_map;
 287                 /* Pointer to the idmap entry for the container's root uid in
 288                  * the id_map list. Do not free! */
 289                 struct id_map *root_nsuid_map;
 290                 /* Pointer to the idmap entry for the container's root gid in
 291                  * the id_map list. Do not free! */
 292                 struct id_map *root_nsgid_map;
 293         };
 294         struct lxc_list network;
 295         int auto_mounts;
 296         struct lxc_list mount_list;
 297         struct lxc_list caps;
 298         struct lxc_list keepcaps;
 299         struct lxc_tty_info tty_info;
 300         /* Comma-separated list of lxc.tty.max pty names. */
 301         char *pty_names;
 302         struct lxc_console console;
 303         struct lxc_rootfs rootfs;
 304         char *ttydir;
 305         int close_all_fds;
 306
 307         struct {
 308                 unsigned int hooks_version;
 309                 struct lxc_list hooks[NUM_LXC_HOOKS];
 310         };
 311
 312         char *lsm_aa_profile;
 313         unsigned int lsm_aa_allow_incomplete;
 314         char *lsm_se_context;
 315         int tmp_umount_proc;
 316         char *seccomp;  /* filename with the seccomp rules */
 317 #if HAVE_SCMP_FILTER_CTX
 318         scmp_filter_ctx seccomp_ctx;
 319 #endif
 320         int maincmd_fd;
 321         unsigned int autodev;  /* if 1, mount and fill a /dev at start */
 322         int haltsignal; /* signal used to halt container */
 323         int rebootsignal; /* signal used to reboot container */
 324         int stopsignal; /* signal used to hard stop container */
 325         char *rcfile;   /* Copy of the top level rcfile we read */
 326
 327         /* Logfile and logleve can be set in a container config file. Those
 328          * function as defaults. The defaults can be overriden by command line.
 329          * However we don't want the command line specified values to be saved
 330          * on c->save_config(). So we store the config file specified values
 331          * here. */
 332         char *logfile; /* the logfile as specifed in config */
 333         int loglevel; /* loglevel as specifed in config (if any) */
 334         int logfd;
 335
 336         unsigned int start_auto;
 337         unsigned int start_delay;
 338         int start_order;
 339         struct lxc_list groups;
 340         int nbd_idx;
 341
 342         /* unshare the mount namespace in the monitor */
 343         unsigned int monitor_unshare;
 344
 345         /* set to true when rootfs has been setup */
 346         bool rootfs_setup;
 347
 348         /* list of included files */
 349         struct lxc_list includes;
 350         /* config entries which are not "lxc.*" are aliens */
 351         struct lxc_list aliens;
 352
 353         /* list of environment variables we'll add to the container when
 354          * started */
 355         struct lxc_list environment;
 356
 357         /* text representation of the config file */
 358         char *unexpanded_config;
 359         size_t unexpanded_len, unexpanded_alloced;
 360
 361         /* default command for lxc-execute */
 362         char *execute_cmd;
 363
 364         /* init command */
 365         char *init_cmd;
 366
 367         /* if running in a new user namespace, the UID/GID that init and COMMAND
 368          * should run under when using lxc-execute */
 369         uid_t init_uid;
 370         gid_t init_gid;
 371
 372         /* indicator if the container will be destroyed on shutdown */
 373         unsigned int ephemeral;
 374
 375         /* The facility to pass to syslog. Let's users establish as what type of
 376          * program liblxc is supposed to write to the syslog. */
 377         char *syslog;
 378
 379         /* Whether PR_SET_NO_NEW_PRIVS will be set for the container. */
 380         bool no_new_privs;
 381
 382         /* RLIMIT_* limits */
 383         struct lxc_list limits;
 384
 385         /* REMOVE IN LXC 3.0
 386          * Indicator whether the current config file we're using contained any
 387          * legacy configuration keys.
 388          */
 389         bool contains_legacy_key;
 390
 391         /* Contains generic info about the cgroup configuration for this
 392          * container. Note that struct lxc_cgroup contains a union. It is only
 393          * valid to access the members of the anonymous "meta" struct within
 394          * that union.
 395          */
 396         struct lxc_cgroup cgroup_meta;
 397
 398         char *inherit_ns[LXC_NS_MAX];
 399
 400         /* init working directory */
 401         char *init_cwd;
 402
 403         /* A list of clients registered to be informed about a container state. */
 404         struct lxc_list state_clients;
 405
 406         /* sysctls */
 407         struct lxc_list sysctls;
 408
 409         /* procs */
 410         struct lxc_list procs;
 411 };
 412
 413 extern int write_id_mapping(enum idtype idtype, pid_t pid, const char *buf,
 414                             size_t buf_size);
 415
 416 #ifdef HAVE_TLS
 417 extern __thread struct lxc_conf *current_config;
 418 #else
 419 extern struct lxc_conf *current_config;
 420 #endif
 421
 422 extern int run_lxc_hooks(const char *name, char *hook, struct lxc_conf *conf,
 423                          char *argv[]);
 424 extern int detect_shared_rootfs(void);
 425 extern struct lxc_conf *lxc_conf_init(void);
 426 extern void lxc_conf_free(struct lxc_conf *conf);
 427 extern int pin_rootfs(const char *rootfs);
 428 extern int lxc_map_ids(struct lxc_list *idmap, pid_t pid);
 429 extern int lxc_create_tty(const char *name, struct lxc_conf *conf);
 430 extern void lxc_delete_tty(struct lxc_tty_info *tty_info);
 431 extern int lxc_clear_config_caps(struct lxc_conf *c);
 432 extern int lxc_clear_config_keepcaps(struct lxc_conf *c);
 433 extern int lxc_clear_cgroups(struct lxc_conf *c, const char *key);
 434 extern int lxc_clear_mount_entries(struct lxc_conf *c);
 435 extern int lxc_clear_automounts(struct lxc_conf *c);
 436 extern int lxc_clear_hooks(struct lxc_conf *c, const char *key);
 437 extern int lxc_clear_idmaps(struct lxc_conf *c);
 438 extern int lxc_clear_groups(struct lxc_conf *c);
 439 extern int lxc_clear_environment(struct lxc_conf *c);
 440 extern int lxc_clear_limits(struct lxc_conf *c, const char *key);
 441 extern int lxc_delete_autodev(struct lxc_handler *handler);
 442 extern void lxc_clear_includes(struct lxc_conf *conf);
 443 extern int do_rootfs_setup(struct lxc_conf *conf, const char *name,
 444                            const char *lxcpath);
 445 extern int lxc_setup(struct lxc_handler *handler);
 446 extern int lxc_setup_parent(struct lxc_handler *handler);
 447 extern int setup_resource_limits(struct lxc_list *limits, pid_t pid);
 448 extern int find_unmapped_nsid(struct lxc_conf *conf, enum idtype idtype);
 449 extern int mapped_hostid(unsigned id, struct lxc_conf *conf,
 450                          enum idtype idtype);
 451 extern int chown_mapped_root(const char *path, struct lxc_conf *conf);
 452 extern int lxc_ttys_shift_ids(struct lxc_conf *c);
 453 extern int userns_exec_1(struct lxc_conf *conf, int (*fn)(void *), void *data,
 454                          const char *fn_name);
 455 extern int userns_exec_full(struct lxc_conf *conf, int (*fn)(void *),
 456                             void *data, const char *fn_name);
 457 extern int parse_mntopts(const char *mntopts, unsigned long *mntflags,
 458                          char **mntdata);
 459 extern void tmp_proc_unmount(struct lxc_conf *lxc_conf);
 460 extern void remount_all_slave(void);
 461 extern void suggest_default_idmap(void);
 462 extern FILE *make_anonymous_mount_file(struct lxc_list *mount);
 463 extern struct lxc_list *sort_cgroup_settings(struct lxc_list *cgroup_settings);
 464 extern unsigned long add_required_remount_flags(const char *s, const char *d,
 465                                                 unsigned long flags);
 466 extern int run_script(const char *name, const char *section, const char *script,
 467                       ...);
 468 extern int run_script_argv(const char *name, unsigned int hook_version,
 469                            const char *section, const char *script,
 470                            const char *hookname, char **argsin);
 471 extern int in_caplist(int cap, struct lxc_list *caps);
 472 extern int setup_sysctl_parameters(struct lxc_list *sysctls);
 473 extern int lxc_clear_sysctls(struct lxc_conf *c, const char *key);
 474 extern int setup_proc_filesystem(struct lxc_list *procs, pid_t pid);
 475 extern int lxc_clear_procs(struct lxc_conf *c, const char *key);
 476
 477 #endif /* __LXC_CONF_H */