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