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