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  * @version   : The version of the cgroup filesystem on which the controller
  56  *              resides.
  57  *
  58  * @controllers : The controllers to use for this container.
  59  * @dir         : The name of the directory containing the container's cgroup.
  60  *                Not that this is a per-container setting.
  61  */
  62 struct lxc_cgroup {
  63         union {
  64                 /* information about a specific controller */
  65                 struct /* controller */ {
  66                         int version;
  67                         char *subsystem;
  68                         char *value;
  69                 };
  70
  71                 /* meta information about cgroup configuration */
  72                 struct /* meta */ {
  73                         char *controllers;
  74                         char *dir;
  75                 };
  76         };
  77 };
  78
  79 #if !HAVE_SYS_RESOURCE_H
  80 # define RLIM_INFINITY ((unsigned long)-1)
  81 struct rlimit {
  82         unsigned long rlim_cur;
  83         unsigned long rlim_max;
  84 };
  85 #endif
  86 /*
  87  * Defines a structure to configure resource limits to set via setrlimit().
  88  * @resource : the resource name in lowercase without the RLIMIT_ prefix
  89  * @limit    : the limit to set
  90  */
  91 struct lxc_limit {
  92         char *resource;
  93         struct rlimit limit;
  94 };
  95
  96 enum idtype {
  97         ID_TYPE_UID,
  98         ID_TYPE_GID
  99 };
 100
 101 /*
 102  * Defines a structure to configure kernel parameters at runtime.
 103  * @key      : the kernel parameters will be configured without the "lxc.sysctl" prefix
 104  * @value    : the value to set
 105  */
 106 struct lxc_sysctl {
 107         char *key;
 108         char *value;
 109 };
 110
 111 /*
 112  * Defines a structure to configure proc filesystem at runtime.
 113  * @filename : the proc filesystem will be configured without the "lxc.proc" prefix
 114  * @value    : the value to set
 115  */
 116 struct lxc_proc {
 117         char *filename;
 118         char *value;
 119 };
 120
 121 /*
 122  * id_map is an id map entry.  Form in confile is:
 123  * lxc.idmap = u 0    9800 100
 124  * lxc.idmap = u 1000 9900 100
 125  * lxc.idmap = g 0    9800 100
 126  * lxc.idmap = g 1000 9900 100
 127  * meaning the container can use uids and gids 0-99 and 1000-1099,
 128  * with [ug]id 0 mapping to [ug]id 9800 on the host, and [ug]id 1000 to
 129  * [ug]id 9900 on the host.
 130  */
 131 struct id_map {
 132         enum idtype idtype;
 133         unsigned long hostid, nsid, range;
 134 };
 135
 136 /*
 137  * Defines a structure containing a pty information for
 138  * virtualizing a tty
 139  * @name   : the path name of the slave pty side
 140  * @master : the file descriptor of the master
 141  * @slave  : the file descriptor of the slave
 142  */
 143 struct lxc_pty_info {
 144         char name[MAXPATHLEN];
 145         int master;
 146         int slave;
 147         int busy;
 148 };
 149
 150 /*
 151  * Defines the number of tty configured and contains the
 152  * instantiated ptys
 153  * @nbtty = number of configured ttys
 154  */
 155 struct lxc_tty_info {
 156         int nbtty;
 157         struct lxc_pty_info *pty_info;
 158 };
 159
 160 struct lxc_tty_state;
 161
 162 /*
 163  * Defines the structure to store the console information
 164  * @peer   : the file descriptor put/get console traffic
 165  * @name   : the file name of the slave pty
 166  */
 167 struct lxc_console {
 168         int slave;
 169         int master;
 170         int peer;
 171         struct lxc_pty_info peerpty;
 172         struct lxc_epoll_descr *descr;
 173         char *path;
 174         char name[MAXPATHLEN];
 175         struct termios *tios;
 176         struct lxc_tty_state *tty_state;
 177
 178         struct /* lxc_console_log */ {
 179                 /* size of the log file */
 180                 uint64_t log_size;
 181
 182                 /* path to the log file */
 183                 char *log_path;
 184
 185                 /* fd to the log file */
 186                 int log_fd;
 187
 188                 /* whether the log file will be rotated */
 189                 unsigned int log_rotate;
 190         };
 191
 192         struct /* lxc_console_ringbuf */ {
 193                 /* size of the ringbuffer */
 194                 uint64_t buffer_size;
 195
 196                 /* the in-memory ringbuffer */
 197                 struct lxc_ringbuf ringbuf;
 198         };
 199 };
 200
 201 /*
 202  * Defines a structure to store the rootfs location, the
 203  * optionals pivot_root, rootfs mount paths
 204  * @path       : the rootfs source (directory or device)
 205  * @mount      : where it is mounted
 206  * @options    : mount options
 207  * @bev_type   : optional backing store type
 208  */
 209 struct lxc_rootfs {
 210         char *path;
 211         char *mount;
 212         char *options;
 213         char *bdev_type;
 214 };
 215
 216 /*
 217  * Automatic mounts for LXC to perform inside the container
 218  */
 219 enum {
 220         LXC_AUTO_PROC_RW              = 0x001,   /* /proc read-write */
 221         LXC_AUTO_PROC_MIXED           = 0x002,   /* /proc/sys and /proc/sysrq-trigger read-only */
 222         LXC_AUTO_PROC_MASK            = 0x003,
 223
 224         LXC_AUTO_SYS_RW               = 0x004,   /* /sys */
 225         LXC_AUTO_SYS_RO               = 0x008,   /* /sys read-only */
 226         LXC_AUTO_SYS_MIXED            = 0x00C,   /* /sys read-only and /sys/class/net read-write */
 227         LXC_AUTO_SYS_MASK             = 0x00C,
 228
 229         LXC_AUTO_CGROUP_RO            = 0x010,   /* /sys/fs/cgroup (partial mount, read-only) */
 230         LXC_AUTO_CGROUP_RW            = 0x020,   /* /sys/fs/cgroup (partial mount, read-write) */
 231         LXC_AUTO_CGROUP_MIXED         = 0x030,   /* /sys/fs/cgroup (partial mount, paths r/o, cgroup r/w) */
 232         LXC_AUTO_CGROUP_FULL_RO       = 0x040,   /* /sys/fs/cgroup (full mount, read-only) */
 233         LXC_AUTO_CGROUP_FULL_RW       = 0x050,   /* /sys/fs/cgroup (full mount, read-write) */
 234         LXC_AUTO_CGROUP_FULL_MIXED    = 0x060,   /* /sys/fs/cgroup (full mount, parent r/o, own r/w) */
 235         /* These are defined in such a way as to retain
 236          * binary compatibility with earlier versions of
 237          * this code. If the previous mask is applied,
 238          * both of these will default back to the _MIXED
 239          * variants, which is safe. */
 240         LXC_AUTO_CGROUP_NOSPEC        = 0x0B0,   /* /sys/fs/cgroup (partial mount, r/w or mixed, depending on caps) */
 241         LXC_AUTO_CGROUP_FULL_NOSPEC   = 0x0E0,   /* /sys/fs/cgroup (full mount, r/w or mixed, depending on caps) */
 242         LXC_AUTO_CGROUP_FORCE         = 0x100,   /* mount cgroups even when cgroup namespaces are supported */
 243         LXC_AUTO_CGROUP_MASK          = 0x1F0,   /* all known cgroup options, doe not contain LXC_AUTO_CGROUP_FORCE */
 244         LXC_AUTO_ALL_MASK             = 0x1FF,   /* all known settings */
 245 };
 246
 247 /*
 248  * Defines the global container configuration
 249  * @rootfs     : root directory to run the container
 250  * @mount      : list of mount points
 251  * @tty        : numbers of tty
 252  * @pts        : new pts instance
 253  * @mount_list : list of mount point (alternative to fstab file)
 254  * @network    : network configuration
 255  * @utsname    : container utsname
 256  * @fstab      : path to a fstab file format
 257  * @caps       : list of the capabilities to drop
 258  * @keepcaps   : list of the capabilities to keep
 259  * @tty_info   : tty data
 260  * @console    : console data
 261  * @ttydir     : directory (under /dev) in which to create console and ttys
 262  * @lsm_aa_profile : apparmor profile to switch to or NULL
 263  * @lsm_se_context : selinux type to switch to or NULL
 264  */
 265 enum lxchooks {
 266         LXCHOOK_PRESTART,
 267         LXCHOOK_PREMOUNT,
 268         LXCHOOK_MOUNT,
 269         LXCHOOK_AUTODEV,
 270         LXCHOOK_START,
 271         LXCHOOK_STOP,
 272         LXCHOOK_POSTSTOP,
 273         LXCHOOK_CLONE,
 274         LXCHOOK_DESTROY,
 275         LXCHOOK_START_HOST,
 276         NUM_LXC_HOOKS
 277 };
 278
 279 extern char *lxchook_names[NUM_LXC_HOOKS];
 280
 281 struct lxc_state_client {
 282         int clientfd;
 283         lxc_state_t states[MAX_STATE];
 284 };
 285
 286 struct lxc_conf {
 287         int is_execute;
 288         char *fstab;
 289         unsigned int tty;
 290         unsigned int pts;
 291         int reboot;
 292         signed long personality;
 293         struct utsname *utsname;
 294         struct {
 295                 struct lxc_list cgroup;
 296                 struct lxc_list cgroup2;
 297         };
 298         struct {
 299                 struct lxc_list id_map;
 300
 301                 /* Pointer to the idmap entry for the container's root uid in
 302                  * the id_map list. Do not free! */
 303                 struct id_map *root_nsuid_map;
 304
 305                 /* Pointer to the idmap entry for the container's root gid in
 306                  * the id_map list. Do not free! */
 307                 struct id_map *root_nsgid_map;
 308         };
 309         struct lxc_list network;
 310         int auto_mounts;
 311         struct lxc_list mount_list;
 312         struct lxc_list caps;
 313         struct lxc_list keepcaps;
 314         struct lxc_tty_info tty_info;
 315         /* Comma-separated list of lxc.tty.max pty names. */
 316         char *pty_names;
 317         struct lxc_console console;
 318         struct lxc_rootfs rootfs;
 319         char *ttydir;
 320         int close_all_fds;
 321
 322         struct {
 323                 unsigned int hooks_version;
 324                 struct lxc_list hooks[NUM_LXC_HOOKS];
 325         };
 326
 327         char *lsm_aa_profile;
 328         unsigned int lsm_aa_allow_incomplete;
 329         char *lsm_se_context;
 330         int tmp_umount_proc;
 331         char *seccomp;  /* filename with the seccomp rules */
 332 #if HAVE_SCMP_FILTER_CTX
 333         scmp_filter_ctx seccomp_ctx;
 334 #endif
 335         int maincmd_fd;
 336         unsigned int autodev;  /* if 1, mount and fill a /dev at start */
 337         int haltsignal; /* signal used to halt container */
 338         int rebootsignal; /* signal used to reboot container */
 339         int stopsignal; /* signal used to hard stop container */
 340         char *rcfile;   /* Copy of the top level rcfile we read */
 341
 342         /* Logfile and logleve can be set in a container config file. Those
 343          * function as defaults. The defaults can be overriden by command line.
 344          * However we don't want the command line specified values to be saved
 345          * on c->save_config(). So we store the config file specified values
 346          * here. */
 347         char *logfile; /* the logfile as specifed in config */
 348         int loglevel; /* loglevel as specifed in config (if any) */
 349         int logfd;
 350
 351         unsigned int start_auto;
 352         unsigned int start_delay;
 353         int start_order;
 354         struct lxc_list groups;
 355         int nbd_idx;
 356
 357         /* unshare the mount namespace in the monitor */
 358         unsigned int monitor_unshare;
 359
 360         /* set to true when rootfs has been setup */
 361         bool rootfs_setup;
 362
 363         /* list of included files */
 364         struct lxc_list includes;
 365         /* config entries which are not "lxc.*" are aliens */
 366         struct lxc_list aliens;
 367
 368         /* list of environment variables we'll add to the container when
 369          * started */
 370         struct lxc_list environment;
 371
 372         /* text representation of the config file */
 373         char *unexpanded_config;
 374         size_t unexpanded_len, unexpanded_alloced;
 375
 376         /* default command for lxc-execute */
 377         char *execute_cmd;
 378
 379         /* init command */
 380         char *init_cmd;
 381
 382         /* if running in a new user namespace, the UID/GID that init and COMMAND
 383          * should run under when using lxc-execute */
 384         uid_t init_uid;
 385         gid_t init_gid;
 386
 387         /* indicator if the container will be destroyed on shutdown */
 388         unsigned int ephemeral;
 389
 390         /* The facility to pass to syslog. Let's users establish as what type of
 391          * program liblxc is supposed to write to the syslog. */
 392         char *syslog;
 393
 394         /* Whether PR_SET_NO_NEW_PRIVS will be set for the container. */
 395         bool no_new_privs;
 396
 397         /* RLIMIT_* limits */
 398         struct lxc_list limits;
 399
 400         /* Contains generic info about the cgroup configuration for this
 401          * container. Note that struct lxc_cgroup contains a union. It is only
 402          * valid to access the members of the anonymous "meta" struct within
 403          * that union.
 404          */
 405         struct lxc_cgroup cgroup_meta;
 406
 407         struct {
 408                 int ns_clone;
 409                 int ns_keep;
 410                 char *ns_share[LXC_NS_MAX];
 411         };
 412
 413         /* init working directory */
 414         char *init_cwd;
 415
 416         /* A list of clients registered to be informed about a container state. */
 417         struct lxc_list state_clients;
 418
 419         /* sysctls */
 420         struct lxc_list sysctls;
 421
 422         /* procs */
 423         struct lxc_list procs;
 424 };
 425
 426 extern int write_id_mapping(enum idtype idtype, pid_t pid, const char *buf,
 427                             size_t buf_size);
 428
 429 #ifdef HAVE_TLS
 430 extern __thread struct lxc_conf *current_config;
 431 #else
 432 extern struct lxc_conf *current_config;
 433 #endif
 434
 435 extern int run_lxc_hooks(const char *name, char *hook, struct lxc_conf *conf,
 436                          char *argv[]);
 437 extern int detect_shared_rootfs(void);
 438 extern struct lxc_conf *lxc_conf_init(void);
 439 extern void lxc_conf_free(struct lxc_conf *conf);
 440 extern int pin_rootfs(const char *rootfs);
 441 extern int lxc_map_ids(struct lxc_list *idmap, pid_t pid);
 442 extern int lxc_create_tty(const char *name, struct lxc_conf *conf);
 443 extern void lxc_delete_tty(struct lxc_tty_info *tty_info);
 444 extern int lxc_clear_config_caps(struct lxc_conf *c);
 445 extern int lxc_clear_config_keepcaps(struct lxc_conf *c);
 446 extern int lxc_clear_cgroups(struct lxc_conf *c, const char *key, int version);
 447 extern int lxc_clear_mount_entries(struct lxc_conf *c);
 448 extern int lxc_clear_automounts(struct lxc_conf *c);
 449 extern int lxc_clear_hooks(struct lxc_conf *c, const char *key);
 450 extern int lxc_clear_idmaps(struct lxc_conf *c);
 451 extern int lxc_clear_groups(struct lxc_conf *c);
 452 extern int lxc_clear_environment(struct lxc_conf *c);
 453 extern int lxc_clear_limits(struct lxc_conf *c, const char *key);
 454 extern int lxc_delete_autodev(struct lxc_handler *handler);
 455 extern void lxc_clear_includes(struct lxc_conf *conf);
 456 extern int do_rootfs_setup(struct lxc_conf *conf, const char *name,
 457                            const char *lxcpath);
 458 extern int lxc_setup(struct lxc_handler *handler);
 459 extern int lxc_setup_parent(struct lxc_handler *handler);
 460 extern int setup_resource_limits(struct lxc_list *limits, pid_t pid);
 461 extern int find_unmapped_nsid(struct lxc_conf *conf, enum idtype idtype);
 462 extern int mapped_hostid(unsigned id, struct lxc_conf *conf,
 463                          enum idtype idtype);
 464 extern int chown_mapped_root(const char *path, struct lxc_conf *conf);
 465 extern int userns_exec_1(struct lxc_conf *conf, int (*fn)(void *), void *data,
 466                          const char *fn_name);
 467 extern int userns_exec_full(struct lxc_conf *conf, int (*fn)(void *),
 468                             void *data, const char *fn_name);
 469 extern int parse_mntopts(const char *mntopts, unsigned long *mntflags,
 470                          char **mntdata);
 471 extern void tmp_proc_unmount(struct lxc_conf *lxc_conf);
 472 extern void remount_all_slave(void);
 473 extern void suggest_default_idmap(void);
 474 extern FILE *make_anonymous_mount_file(struct lxc_list *mount);
 475 extern struct lxc_list *sort_cgroup_settings(struct lxc_list *cgroup_settings);
 476 extern unsigned long add_required_remount_flags(const char *s, const char *d,
 477                                                 unsigned long flags);
 478 extern int run_script(const char *name, const char *section, const char *script,
 479                       ...);
 480 extern int run_script_argv(const char *name, unsigned int hook_version,
 481                            const char *section, const char *script,
 482                            const char *hookname, char **argsin);
 483 extern int in_caplist(int cap, struct lxc_list *caps);
 484 extern int setup_sysctl_parameters(struct lxc_list *sysctls);
 485 extern int lxc_clear_sysctls(struct lxc_conf *c, const char *key);
 486 extern int setup_proc_filesystem(struct lxc_list *procs, pid_t pid);
 487 extern int lxc_clear_procs(struct lxc_conf *c, const char *key);
 488
 489 #endif /* __LXC_CONF_H */