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 *log_path;
 175         int log_fd;
 176         unsigned int log_rotate;
 177         char name[MAXPATHLEN];
 178         struct termios *tios;
 179         struct lxc_tty_state *tty_state;
 180         struct /* lxc_console_ringbuf */ {
 181                 /* size of the ringbuffer */
 182                 uint64_t buffer_size;
 183
 184                 /* path to the log file for the ringbuffer */
 185                 char *buffer_log_file;
 186
 187                 /* fd to the log file for the ringbuffer */
 188                 int buffer_log_file_fd;
 189
 190                 /* the in-memory ringbuffer */
 191                 struct lxc_ringbuf ringbuf;
 192         };
 193 };
 194
 195 /*
 196  * Defines a structure to store the rootfs location, the
 197  * optionals pivot_root, rootfs mount paths
 198  * @path       : the rootfs source (directory or device)
 199  * @mount      : where it is mounted
 200  * @options    : mount options
 201  * @bev_type   : optional backing store type
 202  */
 203 struct lxc_rootfs {
 204         char *path;
 205         char *mount;
 206         char *options;
 207         char *bdev_type;
 208 };
 209
 210 /*
 211  * Automatic mounts for LXC to perform inside the container
 212  */
 213 enum {
 214         LXC_AUTO_PROC_RW              = 0x001,   /* /proc read-write */
 215         LXC_AUTO_PROC_MIXED           = 0x002,   /* /proc/sys and /proc/sysrq-trigger read-only */
 216         LXC_AUTO_PROC_MASK            = 0x003,
 217
 218         LXC_AUTO_SYS_RW               = 0x004,   /* /sys */
 219         LXC_AUTO_SYS_RO               = 0x008,   /* /sys read-only */
 220         LXC_AUTO_SYS_MIXED            = 0x00C,   /* /sys read-only and /sys/class/net read-write */
 221         LXC_AUTO_SYS_MASK             = 0x00C,
 222
 223         LXC_AUTO_CGROUP_RO            = 0x010,   /* /sys/fs/cgroup (partial mount, read-only) */
 224         LXC_AUTO_CGROUP_RW            = 0x020,   /* /sys/fs/cgroup (partial mount, read-write) */
 225         LXC_AUTO_CGROUP_MIXED         = 0x030,   /* /sys/fs/cgroup (partial mount, paths r/o, cgroup r/w) */
 226         LXC_AUTO_CGROUP_FULL_RO       = 0x040,   /* /sys/fs/cgroup (full mount, read-only) */
 227         LXC_AUTO_CGROUP_FULL_RW       = 0x050,   /* /sys/fs/cgroup (full mount, read-write) */
 228         LXC_AUTO_CGROUP_FULL_MIXED    = 0x060,   /* /sys/fs/cgroup (full mount, parent r/o, own r/w) */
 229         /* These are defined in such a way as to retain
 230          * binary compatibility with earlier versions of
 231          * this code. If the previous mask is applied,
 232          * both of these will default back to the _MIXED
 233          * variants, which is safe. */
 234         LXC_AUTO_CGROUP_NOSPEC        = 0x0B0,   /* /sys/fs/cgroup (partial mount, r/w or mixed, depending on caps) */
 235         LXC_AUTO_CGROUP_FULL_NOSPEC   = 0x0E0,   /* /sys/fs/cgroup (full mount, r/w or mixed, depending on caps) */
 236         LXC_AUTO_CGROUP_FORCE         = 0x100,   /* mount cgroups even when cgroup namespaces are supported */
 237         LXC_AUTO_CGROUP_MASK          = 0x1F0,   /* all known cgroup options, doe not contain LXC_AUTO_CGROUP_FORCE */
 238         LXC_AUTO_ALL_MASK             = 0x1FF,   /* all known settings */
 239 };
 240
 241 /*
 242  * Defines the global container configuration
 243  * @rootfs     : root directory to run the container
 244  * @mount      : list of mount points
 245  * @tty        : numbers of tty
 246  * @pts        : new pts instance
 247  * @mount_list : list of mount point (alternative to fstab file)
 248  * @network    : network configuration
 249  * @utsname    : container utsname
 250  * @fstab      : path to a fstab file format
 251  * @caps       : list of the capabilities to drop
 252  * @keepcaps   : list of the capabilities to keep
 253  * @tty_info   : tty data
 254  * @console    : console data
 255  * @ttydir     : directory (under /dev) in which to create console and ttys
 256  * @lsm_aa_profile : apparmor profile to switch to or NULL
 257  * @lsm_se_context : selinux type to switch to or NULL
 258  */
 259 enum lxchooks {
 260         LXCHOOK_PRESTART,
 261         LXCHOOK_PREMOUNT,
 262         LXCHOOK_MOUNT,
 263         LXCHOOK_AUTODEV,
 264         LXCHOOK_START,
 265         LXCHOOK_STOP,
 266         LXCHOOK_POSTSTOP,
 267         LXCHOOK_CLONE,
 268         LXCHOOK_DESTROY,
 269         LXCHOOK_START_HOST,
 270         NUM_LXC_HOOKS
 271 };
 272
 273 extern char *lxchook_names[NUM_LXC_HOOKS];
 274
 275 struct lxc_state_client {
 276         int clientfd;
 277         lxc_state_t states[MAX_STATE];
 278 };
 279
 280 struct lxc_conf {
 281         int is_execute;
 282         char *fstab;
 283         unsigned int tty;
 284         unsigned int pts;
 285         int reboot;
 286         signed long personality;
 287         struct utsname *utsname;
 288         struct {
 289                 struct lxc_list cgroup;
 290                 struct lxc_list cgroup2;
 291         };
 292         struct {
 293                 struct lxc_list id_map;
 294
 295                 /* Pointer to the idmap entry for the container's root uid in
 296                  * the id_map list. Do not free! */
 297                 struct id_map *root_nsuid_map;
 298
 299                 /* Pointer to the idmap entry for the container's root gid in
 300                  * the id_map list. Do not free! */
 301                 struct id_map *root_nsgid_map;
 302         };
 303         struct lxc_list network;
 304         int auto_mounts;
 305         struct lxc_list mount_list;
 306         struct lxc_list caps;
 307         struct lxc_list keepcaps;
 308         struct lxc_tty_info tty_info;
 309         /* Comma-separated list of lxc.tty.max pty names. */
 310         char *pty_names;
 311         struct lxc_console console;
 312         struct lxc_rootfs rootfs;
 313         char *ttydir;
 314         int close_all_fds;
 315
 316         struct {
 317                 unsigned int hooks_version;
 318                 struct lxc_list hooks[NUM_LXC_HOOKS];
 319         };
 320
 321         char *lsm_aa_profile;
 322         unsigned int lsm_aa_allow_incomplete;
 323         char *lsm_se_context;
 324         int tmp_umount_proc;
 325         char *seccomp;  /* filename with the seccomp rules */
 326 #if HAVE_SCMP_FILTER_CTX
 327         scmp_filter_ctx seccomp_ctx;
 328 #endif
 329         int maincmd_fd;
 330         unsigned int autodev;  /* if 1, mount and fill a /dev at start */
 331         int haltsignal; /* signal used to halt container */
 332         int rebootsignal; /* signal used to reboot container */
 333         int stopsignal; /* signal used to hard stop container */
 334         char *rcfile;   /* Copy of the top level rcfile we read */
 335
 336         /* Logfile and logleve can be set in a container config file. Those
 337          * function as defaults. The defaults can be overriden by command line.
 338          * However we don't want the command line specified values to be saved
 339          * on c->save_config(). So we store the config file specified values
 340          * here. */
 341         char *logfile; /* the logfile as specifed in config */
 342         int loglevel; /* loglevel as specifed in config (if any) */
 343         int logfd;
 344
 345         unsigned int start_auto;
 346         unsigned int start_delay;
 347         int start_order;
 348         struct lxc_list groups;
 349         int nbd_idx;
 350
 351         /* unshare the mount namespace in the monitor */
 352         unsigned int monitor_unshare;
 353
 354         /* set to true when rootfs has been setup */
 355         bool rootfs_setup;
 356
 357         /* list of included files */
 358         struct lxc_list includes;
 359         /* config entries which are not "lxc.*" are aliens */
 360         struct lxc_list aliens;
 361
 362         /* list of environment variables we'll add to the container when
 363          * started */
 364         struct lxc_list environment;
 365
 366         /* text representation of the config file */
 367         char *unexpanded_config;
 368         size_t unexpanded_len, unexpanded_alloced;
 369
 370         /* default command for lxc-execute */
 371         char *execute_cmd;
 372
 373         /* init command */
 374         char *init_cmd;
 375
 376         /* if running in a new user namespace, the UID/GID that init and COMMAND
 377          * should run under when using lxc-execute */
 378         uid_t init_uid;
 379         gid_t init_gid;
 380
 381         /* indicator if the container will be destroyed on shutdown */
 382         unsigned int ephemeral;
 383
 384         /* The facility to pass to syslog. Let's users establish as what type of
 385          * program liblxc is supposed to write to the syslog. */
 386         char *syslog;
 387
 388         /* Whether PR_SET_NO_NEW_PRIVS will be set for the container. */
 389         bool no_new_privs;
 390
 391         /* RLIMIT_* limits */
 392         struct lxc_list limits;
 393
 394         /* Contains generic info about the cgroup configuration for this
 395          * container. Note that struct lxc_cgroup contains a union. It is only
 396          * valid to access the members of the anonymous "meta" struct within
 397          * that union.
 398          */
 399         struct lxc_cgroup cgroup_meta;
 400
 401         struct {
 402                 int ns_clone;
 403                 int ns_keep;
 404                 char *ns_share[LXC_NS_MAX];
 405         };
 406
 407         /* init working directory */
 408         char *init_cwd;
 409
 410         /* A list of clients registered to be informed about a container state. */
 411         struct lxc_list state_clients;
 412
 413         /* sysctls */
 414         struct lxc_list sysctls;
 415
 416         /* procs */
 417         struct lxc_list procs;
 418 };
 419
 420 extern int write_id_mapping(enum idtype idtype, pid_t pid, const char *buf,
 421                             size_t buf_size);
 422
 423 #ifdef HAVE_TLS
 424 extern __thread struct lxc_conf *current_config;
 425 #else
 426 extern struct lxc_conf *current_config;
 427 #endif
 428
 429 extern int run_lxc_hooks(const char *name, char *hook, struct lxc_conf *conf,
 430                          char *argv[]);
 431 extern int detect_shared_rootfs(void);
 432 extern struct lxc_conf *lxc_conf_init(void);
 433 extern void lxc_conf_free(struct lxc_conf *conf);
 434 extern int pin_rootfs(const char *rootfs);
 435 extern int lxc_map_ids(struct lxc_list *idmap, pid_t pid);
 436 extern int lxc_create_tty(const char *name, struct lxc_conf *conf);
 437 extern void lxc_delete_tty(struct lxc_tty_info *tty_info);
 438 extern int lxc_clear_config_caps(struct lxc_conf *c);
 439 extern int lxc_clear_config_keepcaps(struct lxc_conf *c);
 440 extern int lxc_clear_cgroups(struct lxc_conf *c, const char *key, int version);
 441 extern int lxc_clear_mount_entries(struct lxc_conf *c);
 442 extern int lxc_clear_automounts(struct lxc_conf *c);
 443 extern int lxc_clear_hooks(struct lxc_conf *c, const char *key);
 444 extern int lxc_clear_idmaps(struct lxc_conf *c);
 445 extern int lxc_clear_groups(struct lxc_conf *c);
 446 extern int lxc_clear_environment(struct lxc_conf *c);
 447 extern int lxc_clear_limits(struct lxc_conf *c, const char *key);
 448 extern int lxc_delete_autodev(struct lxc_handler *handler);
 449 extern void lxc_clear_includes(struct lxc_conf *conf);
 450 extern int do_rootfs_setup(struct lxc_conf *conf, const char *name,
 451                            const char *lxcpath);
 452 extern int lxc_setup(struct lxc_handler *handler);
 453 extern int lxc_setup_parent(struct lxc_handler *handler);
 454 extern int setup_resource_limits(struct lxc_list *limits, pid_t pid);
 455 extern int find_unmapped_nsid(struct lxc_conf *conf, enum idtype idtype);
 456 extern int mapped_hostid(unsigned id, struct lxc_conf *conf,
 457                          enum idtype idtype);
 458 extern int chown_mapped_root(const char *path, struct lxc_conf *conf);
 459 extern int userns_exec_1(struct lxc_conf *conf, int (*fn)(void *), void *data,
 460                          const char *fn_name);
 461 extern int userns_exec_full(struct lxc_conf *conf, int (*fn)(void *),
 462                             void *data, const char *fn_name);
 463 extern int parse_mntopts(const char *mntopts, unsigned long *mntflags,
 464                          char **mntdata);
 465 extern void tmp_proc_unmount(struct lxc_conf *lxc_conf);
 466 extern void remount_all_slave(void);
 467 extern void suggest_default_idmap(void);
 468 extern FILE *make_anonymous_mount_file(struct lxc_list *mount);
 469 extern struct lxc_list *sort_cgroup_settings(struct lxc_list *cgroup_settings);
 470 extern unsigned long add_required_remount_flags(const char *s, const char *d,
 471                                                 unsigned long flags);
 472 extern int run_script(const char *name, const char *section, const char *script,
 473                       ...);
 474 extern int run_script_argv(const char *name, unsigned int hook_version,
 475                            const char *section, const char *script,
 476                            const char *hookname, char **argsin);
 477 extern int in_caplist(int cap, struct lxc_list *caps);
 478 extern int setup_sysctl_parameters(struct lxc_list *sysctls);
 479 extern int lxc_clear_sysctls(struct lxc_conf *c, const char *key);
 480 extern int setup_proc_filesystem(struct lxc_list *procs, pid_t pid);
 481 extern int lxc_clear_procs(struct lxc_conf *c, const char *key);
 482
 483 #endif /* __LXC_CONF_H */