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  * id_map is an id map entry.  Form in confile is:
 100  * lxc.idmap = u 0    9800 100
 101  * lxc.idmap = u 1000 9900 100
 102  * lxc.idmap = g 0    9800 100
 103  * lxc.idmap = g 1000 9900 100
 104  * meaning the container can use uids and gids 0-99 and 1000-1099,
 105  * with [ug]id 0 mapping to [ug]id 9800 on the host, and [ug]id 1000 to
 106  * [ug]id 9900 on the host.
 107  */
 108 struct id_map {
 109         enum idtype idtype;
 110         unsigned long hostid, nsid, range;
 111 };
 112
 113 /*
 114  * Defines a structure containing a pty information for
 115  * virtualizing a tty
 116  * @name   : the path name of the slave pty side
 117  * @master : the file descriptor of the master
 118  * @slave  : the file descriptor of the slave
 119  */
 120 struct lxc_pty_info {
 121         char name[MAXPATHLEN];
 122         int master;
 123         int slave;
 124         int busy;
 125 };
 126
 127 /*
 128  * Defines the number of tty configured and contains the
 129  * instantiated ptys
 130  * @nbtty = number of configured ttys
 131  */
 132 struct lxc_tty_info {
 133         int nbtty;
 134         struct lxc_pty_info *pty_info;
 135 };
 136
 137 struct lxc_tty_state;
 138
 139 /*
 140  * Defines the structure to store the console information
 141  * @peer   : the file descriptor put/get console traffic
 142  * @name   : the file name of the slave pty
 143  */
 144 struct lxc_console {
 145         int slave;
 146         int master;
 147         int peer;
 148         struct lxc_pty_info peerpty;
 149         struct lxc_epoll_descr *descr;
 150         char *path;
 151         char *log_path;
 152         int log_fd;
 153         char name[MAXPATHLEN];
 154         struct termios *tios;
 155         struct lxc_tty_state *tty_state;
 156         uint64_t log_size;
 157         struct lxc_ringbuf ringbuf;
 158 };
 159
 160 /*
 161  * Defines a structure to store the rootfs location, the
 162  * optionals pivot_root, rootfs mount paths
 163  * @path       : the rootfs source (directory or device)
 164  * @mount      : where it is mounted
 165  * @options    : mount options
 166  * @bev_type   : optional backing store type
 167  */
 168 struct lxc_rootfs {
 169         char *path;
 170         char *mount;
 171         char *options;
 172         char *bdev_type;
 173 };
 174
 175 /*
 176  * Automatic mounts for LXC to perform inside the container
 177  */
 178 enum {
 179         LXC_AUTO_PROC_RW              = 0x001,   /* /proc read-write */
 180         LXC_AUTO_PROC_MIXED           = 0x002,   /* /proc/sys and /proc/sysrq-trigger read-only */
 181         LXC_AUTO_PROC_MASK            = 0x003,
 182
 183         LXC_AUTO_SYS_RW               = 0x004,   /* /sys */
 184         LXC_AUTO_SYS_RO               = 0x008,   /* /sys read-only */
 185         LXC_AUTO_SYS_MIXED            = 0x00C,   /* /sys read-only and /sys/class/net read-write */
 186         LXC_AUTO_SYS_MASK             = 0x00C,
 187
 188         LXC_AUTO_CGROUP_RO            = 0x010,   /* /sys/fs/cgroup (partial mount, read-only) */
 189         LXC_AUTO_CGROUP_RW            = 0x020,   /* /sys/fs/cgroup (partial mount, read-write) */
 190         LXC_AUTO_CGROUP_MIXED         = 0x030,   /* /sys/fs/cgroup (partial mount, paths r/o, cgroup r/w) */
 191         LXC_AUTO_CGROUP_FULL_RO       = 0x040,   /* /sys/fs/cgroup (full mount, read-only) */
 192         LXC_AUTO_CGROUP_FULL_RW       = 0x050,   /* /sys/fs/cgroup (full mount, read-write) */
 193         LXC_AUTO_CGROUP_FULL_MIXED    = 0x060,   /* /sys/fs/cgroup (full mount, parent r/o, own r/w) */
 194         /* These are defined in such a way as to retain
 195          * binary compatibility with earlier versions of
 196          * this code. If the previous mask is applied,
 197          * both of these will default back to the _MIXED
 198          * variants, which is safe. */
 199         LXC_AUTO_CGROUP_NOSPEC        = 0x0B0,   /* /sys/fs/cgroup (partial mount, r/w or mixed, depending on caps) */
 200         LXC_AUTO_CGROUP_FULL_NOSPEC   = 0x0E0,   /* /sys/fs/cgroup (full mount, r/w or mixed, depending on caps) */
 201         LXC_AUTO_CGROUP_MASK          = 0x0F0,
 202
 203         LXC_AUTO_ALL_MASK             = 0x0FF,   /* all known settings */
 204 };
 205
 206 /*
 207  * Defines the global container configuration
 208  * @rootfs     : root directory to run the container
 209  * @mount      : list of mount points
 210  * @tty        : numbers of tty
 211  * @pts        : new pts instance
 212  * @mount_list : list of mount point (alternative to fstab file)
 213  * @network    : network configuration
 214  * @utsname    : container utsname
 215  * @fstab      : path to a fstab file format
 216  * @caps       : list of the capabilities to drop
 217  * @keepcaps   : list of the capabilities to keep
 218  * @tty_info   : tty data
 219  * @console    : console data
 220  * @ttydir     : directory (under /dev) in which to create console and ttys
 221  * @lsm_aa_profile : apparmor profile to switch to or NULL
 222  * @lsm_se_context : selinux type to switch to or NULL
 223  */
 224 enum lxchooks {
 225         LXCHOOK_PRESTART,
 226         LXCHOOK_PREMOUNT,
 227         LXCHOOK_MOUNT,
 228         LXCHOOK_AUTODEV,
 229         LXCHOOK_START,
 230         LXCHOOK_STOP,
 231         LXCHOOK_POSTSTOP,
 232         LXCHOOK_CLONE,
 233         LXCHOOK_DESTROY,
 234         LXCHOOK_START_HOST,
 235         NUM_LXC_HOOKS
 236 };
 237
 238 extern char *lxchook_names[NUM_LXC_HOOKS];
 239
 240 struct lxc_conf {
 241         int is_execute;
 242         char *fstab;
 243         unsigned int tty;
 244         unsigned int pts;
 245         int reboot;
 246         signed long personality;
 247         struct utsname *utsname;
 248         struct lxc_list cgroup;
 249         struct lxc_list id_map;
 250         struct lxc_list network;
 251         int auto_mounts;
 252         struct lxc_list mount_list;
 253         struct lxc_list caps;
 254         struct lxc_list keepcaps;
 255         struct lxc_tty_info tty_info;
 256         /* Comma-separated list of lxc.tty.max pty names. */
 257         char *pty_names;
 258         struct lxc_console console;
 259         struct lxc_rootfs rootfs;
 260         char *ttydir;
 261         int close_all_fds;
 262         struct lxc_list hooks[NUM_LXC_HOOKS];
 263
 264         char *lsm_aa_profile;
 265         unsigned int lsm_aa_allow_incomplete;
 266         char *lsm_se_context;
 267         int tmp_umount_proc;
 268         char *seccomp;  /* filename with the seccomp rules */
 269 #if HAVE_SCMP_FILTER_CTX
 270         scmp_filter_ctx seccomp_ctx;
 271 #endif
 272         int maincmd_fd;
 273         unsigned int autodev;  /* if 1, mount and fill a /dev at start */
 274         int haltsignal; /* signal used to halt container */
 275         int rebootsignal; /* signal used to reboot container */
 276         int stopsignal; /* signal used to hard stop container */
 277         char *rcfile;   /* Copy of the top level rcfile we read */
 278
 279         /* Logfile and logleve can be set in a container config file. Those
 280          * function as defaults. The defaults can be overriden by command line.
 281          * However we don't want the command line specified values to be saved
 282          * on c->save_config(). So we store the config file specified values
 283          * here. */
 284         char *logfile; /* the logfile as specifed in config */
 285         int loglevel; /* loglevel as specifed in config (if any) */
 286         int logfd;
 287
 288         unsigned int start_auto;
 289         unsigned int start_delay;
 290         int start_order;
 291         struct lxc_list groups;
 292         int nbd_idx;
 293
 294         /* unshare the mount namespace in the monitor */
 295         unsigned int monitor_unshare;
 296
 297         /* set to true when rootfs has been setup */
 298         bool rootfs_setup;
 299
 300         /* list of included files */
 301         struct lxc_list includes;
 302         /* config entries which are not "lxc.*" are aliens */
 303         struct lxc_list aliens;
 304
 305         /* list of environment variables we'll add to the container when
 306          * started */
 307         struct lxc_list environment;
 308
 309         /* text representation of the config file */
 310         char *unexpanded_config;
 311         size_t unexpanded_len, unexpanded_alloced;
 312
 313         /* default command for lxc-execute */
 314         char *execute_cmd;
 315
 316         /* init command */
 317         char *init_cmd;
 318
 319         /* if running in a new user namespace, the UID/GID that init and COMMAND
 320          * should run under when using lxc-execute */
 321         uid_t init_uid;
 322         gid_t init_gid;
 323
 324         /* indicator if the container will be destroyed on shutdown */
 325         unsigned int ephemeral;
 326
 327         /* The facility to pass to syslog. Let's users establish as what type of
 328          * program liblxc is supposed to write to the syslog. */
 329         char *syslog;
 330
 331         /* Whether PR_SET_NO_NEW_PRIVS will be set for the container. */
 332         bool no_new_privs;
 333
 334         /* RLIMIT_* limits */
 335         struct lxc_list limits;
 336
 337         /* REMOVE IN LXC 3.0
 338          * Indicator whether the current config file we're using contained any
 339          * legacy configuration keys.
 340          */
 341         bool contains_legacy_key;
 342
 343         /* Contains generic info about the cgroup configuration for this
 344          * container. Note that struct lxc_cgroup contains a union. It is only
 345          * valid to access the members of the anonymous "meta" struct within
 346          * that union.
 347          */
 348         struct lxc_cgroup cgroup_meta;
 349
 350         char *inherit_ns[LXC_NS_MAX];
 351 };
 352
 353 #ifdef HAVE_TLS
 354 extern __thread struct lxc_conf *current_config;
 355 #else
 356 extern struct lxc_conf *current_config;
 357 #endif
 358
 359 extern int run_lxc_hooks(const char *name, char *hook, struct lxc_conf *conf,
 360                          const char *lxcpath, char *argv[]);
 361 extern int detect_shared_rootfs(void);
 362 extern struct lxc_conf *lxc_conf_init(void);
 363 extern void lxc_conf_free(struct lxc_conf *conf);
 364 extern int pin_rootfs(const char *rootfs);
 365 extern int lxc_map_ids(struct lxc_list *idmap, pid_t pid);
 366 extern int lxc_create_tty(const char *name, struct lxc_conf *conf);
 367 extern void lxc_delete_tty(struct lxc_tty_info *tty_info);
 368 extern int lxc_clear_config_caps(struct lxc_conf *c);
 369 extern int lxc_clear_config_keepcaps(struct lxc_conf *c);
 370 extern int lxc_clear_cgroups(struct lxc_conf *c, const char *key);
 371 extern int lxc_clear_mount_entries(struct lxc_conf *c);
 372 extern int lxc_clear_automounts(struct lxc_conf *c);
 373 extern int lxc_clear_hooks(struct lxc_conf *c, const char *key);
 374 extern int lxc_clear_idmaps(struct lxc_conf *c);
 375 extern int lxc_clear_groups(struct lxc_conf *c);
 376 extern int lxc_clear_environment(struct lxc_conf *c);
 377 extern int lxc_clear_limits(struct lxc_conf *c, const char *key);
 378 extern int lxc_delete_autodev(struct lxc_handler *handler);
 379 extern void lxc_clear_includes(struct lxc_conf *conf);
 380 extern int do_rootfs_setup(struct lxc_conf *conf, const char *name,
 381                            const char *lxcpath);
 382 extern int lxc_setup(struct lxc_handler *handler);
 383 extern int lxc_setup_parent(struct lxc_handler *handler);
 384 extern int setup_resource_limits(struct lxc_list *limits, pid_t pid);
 385 extern int find_unmapped_nsid(struct lxc_conf *conf, enum idtype idtype);
 386 extern int mapped_hostid(unsigned id, struct lxc_conf *conf,
 387                          enum idtype idtype);
 388 extern int chown_mapped_root(char *path, struct lxc_conf *conf);
 389 extern int lxc_ttys_shift_ids(struct lxc_conf *c);
 390 extern int userns_exec_1(struct lxc_conf *conf, int (*fn)(void *), void *data,
 391                          const char *fn_name);
 392 extern int userns_exec_full(struct lxc_conf *conf, int (*fn)(void *),
 393                             void *data, const char *fn_name);
 394 extern int parse_mntopts(const char *mntopts, unsigned long *mntflags,
 395                          char **mntdata);
 396 extern void tmp_proc_unmount(struct lxc_conf *lxc_conf);
 397 extern void remount_all_slave(void);
 398 extern void suggest_default_idmap(void);
 399 extern FILE *make_anonymous_mount_file(struct lxc_list *mount);
 400 extern struct lxc_list *sort_cgroup_settings(struct lxc_list *cgroup_settings);
 401 extern unsigned long add_required_remount_flags(const char *s, const char *d,
 402                                                 unsigned long flags);
 403 extern int run_script(const char *name, const char *section, const char *script,
 404                       ...);
 405 extern int in_caplist(int cap, struct lxc_list *caps);
 406
 407 #endif /* __LXC_CONF_H */