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 "start.h" /* for lxc_handler */
  40
  41 #if HAVE_SCMP_FILTER_CTX
  42 typedef void * scmp_filter_ctx;
  43 #endif
  44
  45 /* worth moving to configure.ac? */
  46 #define subuidfile "/etc/subuid"
  47 #define subgidfile "/etc/subgid"
  48
  49 /*
  50  * Defines a generic struct to configure the control group. It is up to the
  51  * programmer to specify the right subsystem.
  52  * @subsystem : the targeted subsystem
  53  * @value     : the value to set
  54  *
  55  * @controllers : The controllers to use for this container.
  56  * @dir         : The name of the directory containing the container's cgroup.
  57  *                Not that this is a per-container setting.
  58  */
  59 struct lxc_cgroup {
  60         union {
  61                 /* information about a specific controller */
  62                 struct /* controller */ {
  63                         char *subsystem;
  64                         char *value;
  65                 };
  66
  67                 /* meta information about cgroup configuration */
  68                 struct /* meta */ {
  69                         char *controllers;
  70                         char *dir;
  71                 };
  72         };
  73 };
  74
  75 #if !HAVE_SYS_RESOURCE_H
  76 # define RLIM_INFINITY ((unsigned long)-1)
  77 struct rlimit {
  78         unsigned long rlim_cur;
  79         unsigned long rlim_max;
  80 };
  81 #endif
  82 /*
  83  * Defines a structure to configure resource limits to set via setrlimit().
  84  * @resource : the resource name in lowercase without the RLIMIT_ prefix
  85  * @limit    : the limit to set
  86  */
  87 struct lxc_limit {
  88         char *resource;
  89         struct rlimit limit;
  90 };
  91
  92 enum idtype {
  93         ID_TYPE_UID,
  94         ID_TYPE_GID
  95 };
  96
  97 /*
  98  * id_map is an id map entry.  Form in confile is:
  99  * lxc.id_map = u 0    9800 100
 100  * lxc.id_map = u 1000 9900 100
 101  * lxc.id_map = g 0    9800 100
 102  * lxc.id_map = g 1000 9900 100
 103  * meaning the container can use uids and gids 0-99 and 1000-1099,
 104  * with [ug]id 0 mapping to [ug]id 9800 on the host, and [ug]id 1000 to
 105  * [ug]id 9900 on the host.
 106  */
 107 struct id_map {
 108         enum idtype idtype;
 109         unsigned long hostid, nsid, range;
 110 };
 111
 112 /*
 113  * Defines a structure containing a pty information for
 114  * virtualizing a tty
 115  * @name   : the path name of the slave pty side
 116  * @master : the file descriptor of the master
 117  * @slave  : the file descriptor of the slave
 118  */
 119 struct lxc_pty_info {
 120         char name[MAXPATHLEN];
 121         int master;
 122         int slave;
 123         int busy;
 124 };
 125
 126 /*
 127  * Defines the number of tty configured and contains the
 128  * instantiated ptys
 129  * @nbtty = number of configured ttys
 130  */
 131 struct lxc_tty_info {
 132         int nbtty;
 133         struct lxc_pty_info *pty_info;
 134 };
 135
 136 struct lxc_tty_state;
 137
 138 /*
 139  * Defines the structure to store the console information
 140  * @peer   : the file descriptor put/get console traffic
 141  * @name   : the file name of the slave pty
 142  */
 143 struct lxc_console {
 144         int slave;
 145         int master;
 146         int peer;
 147         struct lxc_pty_info peerpty;
 148         struct lxc_epoll_descr *descr;
 149         char *path;
 150         char *log_path;
 151         int log_fd;
 152         char name[MAXPATHLEN];
 153         struct termios *tios;
 154         struct lxc_tty_state *tty_state;
 155 };
 156
 157 /*
 158  * Defines a structure to store the rootfs location, the
 159  * optionals pivot_root, rootfs mount paths
 160  * @path       : the rootfs source (directory or device)
 161  * @mount      : where it is mounted
 162  * @options    : mount options
 163  * @bev_type   : optional backing store type
 164  */
 165 struct lxc_rootfs {
 166         char *path;
 167         char *mount;
 168         char *options;
 169         char *bdev_type;
 170 };
 171
 172 /*
 173  * Automatic mounts for LXC to perform inside the container
 174  */
 175 enum {
 176         LXC_AUTO_PROC_RW              = 0x001,   /* /proc read-write */
 177         LXC_AUTO_PROC_MIXED           = 0x002,   /* /proc/sys and /proc/sysrq-trigger read-only */
 178         LXC_AUTO_PROC_MASK            = 0x003,
 179
 180         LXC_AUTO_SYS_RW               = 0x004,   /* /sys */
 181         LXC_AUTO_SYS_RO               = 0x008,   /* /sys read-only */
 182         LXC_AUTO_SYS_MIXED            = 0x00C,   /* /sys read-only and /sys/class/net read-write */
 183         LXC_AUTO_SYS_MASK             = 0x00C,
 184
 185         LXC_AUTO_CGROUP_RO            = 0x010,   /* /sys/fs/cgroup (partial mount, read-only) */
 186         LXC_AUTO_CGROUP_RW            = 0x020,   /* /sys/fs/cgroup (partial mount, read-write) */
 187         LXC_AUTO_CGROUP_MIXED         = 0x030,   /* /sys/fs/cgroup (partial mount, paths r/o, cgroup r/w) */
 188         LXC_AUTO_CGROUP_FULL_RO       = 0x040,   /* /sys/fs/cgroup (full mount, read-only) */
 189         LXC_AUTO_CGROUP_FULL_RW       = 0x050,   /* /sys/fs/cgroup (full mount, read-write) */
 190         LXC_AUTO_CGROUP_FULL_MIXED    = 0x060,   /* /sys/fs/cgroup (full mount, parent r/o, own r/w) */
 191         /* These are defined in such a way as to retain
 192          * binary compatibility with earlier versions of
 193          * this code. If the previous mask is applied,
 194          * both of these will default back to the _MIXED
 195          * variants, which is safe. */
 196         LXC_AUTO_CGROUP_NOSPEC        = 0x0B0,   /* /sys/fs/cgroup (partial mount, r/w or mixed, depending on caps) */
 197         LXC_AUTO_CGROUP_FULL_NOSPEC   = 0x0E0,   /* /sys/fs/cgroup (full mount, r/w or mixed, depending on caps) */
 198         LXC_AUTO_CGROUP_MASK          = 0x0F0,
 199
 200         LXC_AUTO_ALL_MASK             = 0x0FF,   /* all known settings */
 201 };
 202
 203 /*
 204  * Defines the global container configuration
 205  * @rootfs     : root directory to run the container
 206  * @mount      : list of mount points
 207  * @tty        : numbers of tty
 208  * @pts        : new pts instance
 209  * @mount_list : list of mount point (alternative to fstab file)
 210  * @network    : network configuration
 211  * @utsname    : container utsname
 212  * @fstab      : path to a fstab file format
 213  * @caps       : list of the capabilities to drop
 214  * @keepcaps   : list of the capabilities to keep
 215  * @tty_info   : tty data
 216  * @console    : console data
 217  * @ttydir     : directory (under /dev) in which to create console and ttys
 218  * @lsm_aa_profile : apparmor profile to switch to or NULL
 219  * @lsm_se_context : selinux type to switch to or NULL
 220  */
 221 enum lxchooks {
 222         LXCHOOK_PRESTART,
 223         LXCHOOK_PREMOUNT,
 224         LXCHOOK_MOUNT,
 225         LXCHOOK_AUTODEV,
 226         LXCHOOK_START,
 227         LXCHOOK_STOP,
 228         LXCHOOK_POSTSTOP,
 229         LXCHOOK_CLONE,
 230         LXCHOOK_DESTROY,
 231         NUM_LXC_HOOKS
 232 };
 233
 234 extern char *lxchook_names[NUM_LXC_HOOKS];
 235
 236 struct lxc_conf {
 237         int is_execute;
 238         char *fstab;
 239         unsigned int tty;
 240         unsigned int pts;
 241         int reboot;
 242         signed long personality;
 243         struct utsname *utsname;
 244         struct lxc_list cgroup;
 245         struct lxc_list id_map;
 246         struct lxc_list network;
 247         int auto_mounts;
 248         struct lxc_list mount_list;
 249         struct lxc_list caps;
 250         struct lxc_list keepcaps;
 251         struct lxc_tty_info tty_info;
 252         /* Comma-separated list of lxc.tty.max pty names. */
 253         char *pty_names;
 254         struct lxc_console console;
 255         struct lxc_rootfs rootfs;
 256         char *ttydir;
 257         int close_all_fds;
 258         struct lxc_list hooks[NUM_LXC_HOOKS];
 259
 260         char *lsm_aa_profile;
 261         unsigned int lsm_aa_allow_incomplete;
 262         char *lsm_se_context;
 263         int tmp_umount_proc;
 264         char *seccomp;  /* filename with the seccomp rules */
 265 #if HAVE_SCMP_FILTER_CTX
 266         scmp_filter_ctx seccomp_ctx;
 267 #endif
 268         int maincmd_fd;
 269         unsigned int autodev;  /* if 1, mount and fill a /dev at start */
 270         int haltsignal; /* signal used to halt container */
 271         int rebootsignal; /* signal used to reboot container */
 272         int stopsignal; /* signal used to hard stop container */
 273         char *rcfile;   /* Copy of the top level rcfile we read */
 274
 275         /* Logfile and logleve can be set in a container config file. Those
 276          * function as defaults. The defaults can be overriden by command line.
 277          * However we don't want the command line specified values to be saved
 278          * on c->save_config(). So we store the config file specified values
 279          * here. */
 280         char *logfile; /* the logfile as specifed in config */
 281         int loglevel; /* loglevel as specifed in config (if any) */
 282         int logfd;
 283
 284         int inherit_ns_fd[LXC_NS_MAX];
 285
 286         unsigned int start_auto;
 287         unsigned int start_delay;
 288         int start_order;
 289         struct lxc_list groups;
 290         int nbd_idx;
 291
 292         /* unshare the mount namespace in the monitor */
 293         unsigned int monitor_unshare;
 294
 295         /* set to true when rootfs has been setup */
 296         bool rootfs_setup;
 297
 298         /* list of included files */
 299         struct lxc_list includes;
 300         /* config entries which are not "lxc.*" are aliens */
 301         struct lxc_list aliens;
 302
 303         /* list of environment variables we'll add to the container when
 304          * started */
 305         struct lxc_list environment;
 306
 307         /* text representation of the config file */
 308         char *unexpanded_config;
 309         size_t unexpanded_len, unexpanded_alloced;
 310
 311         /* init command */
 312         char *init_cmd;
 313
 314         /* if running in a new user namespace, the UID/GID that init and COMMAND
 315          * should run under when using lxc-execute */
 316         uid_t init_uid;
 317         gid_t init_gid;
 318
 319         /* indicator if the container will be destroyed on shutdown */
 320         unsigned int ephemeral;
 321
 322         /* The facility to pass to syslog. Let's users establish as what type of
 323          * program liblxc is supposed to write to the syslog. */
 324         char *syslog;
 325
 326         /* Whether PR_SET_NO_NEW_PRIVS will be set for the container. */
 327         bool no_new_privs;
 328
 329         /* RLIMIT_* limits */
 330         struct lxc_list limits;
 331
 332         /* REMOVE IN LXC 3.0
 333          * Indicator whether the current config file we're using contained any
 334          * legacy configuration keys.
 335          */
 336         bool contains_legacy_key;
 337
 338         /* Contains generic info about the cgroup configuration for this
 339          * container. Note that struct lxc_cgroup contains a union. It is only
 340          * valid to access the members of the anonymous "meta" struct within
 341          * that union.
 342          */
 343         struct lxc_cgroup cgroup_meta;
 344 };
 345
 346 #ifdef HAVE_TLS
 347 extern __thread struct lxc_conf *current_config;
 348 #else
 349 extern struct lxc_conf *current_config;
 350 #endif
 351
 352 extern int run_lxc_hooks(const char *name, char *hook, struct lxc_conf *conf,
 353                          const char *lxcpath, char *argv[]);
 354 extern int detect_shared_rootfs(void);
 355 extern struct lxc_conf *lxc_conf_init(void);
 356 extern void lxc_conf_free(struct lxc_conf *conf);
 357 extern int pin_rootfs(const char *rootfs);
 358 extern int lxc_map_ids(struct lxc_list *idmap, pid_t pid);
 359 extern int lxc_create_tty(const char *name, struct lxc_conf *conf);
 360 extern void lxc_delete_tty(struct lxc_tty_info *tty_info);
 361 extern int lxc_clear_config_caps(struct lxc_conf *c);
 362 extern int lxc_clear_config_keepcaps(struct lxc_conf *c);
 363 extern int lxc_clear_cgroups(struct lxc_conf *c, const char *key);
 364 extern int lxc_clear_mount_entries(struct lxc_conf *c);
 365 extern int lxc_clear_automounts(struct lxc_conf *c);
 366 extern int lxc_clear_hooks(struct lxc_conf *c, const char *key);
 367 extern int lxc_clear_idmaps(struct lxc_conf *c);
 368 extern int lxc_clear_groups(struct lxc_conf *c);
 369 extern int lxc_clear_environment(struct lxc_conf *c);
 370 extern int lxc_clear_limits(struct lxc_conf *c, const char *key);
 371 extern int lxc_delete_autodev(struct lxc_handler *handler);
 372 extern void lxc_clear_includes(struct lxc_conf *conf);
 373 extern int do_rootfs_setup(struct lxc_conf *conf, const char *name,
 374                            const char *lxcpath);
 375 extern int lxc_setup(struct lxc_handler *handler);
 376 extern int setup_resource_limits(struct lxc_list *limits, pid_t pid);
 377 extern int find_unmapped_nsid(struct lxc_conf *conf, enum idtype idtype);
 378 extern int mapped_hostid(unsigned id, struct lxc_conf *conf,
 379                          enum idtype idtype);
 380 extern int chown_mapped_root(char *path, struct lxc_conf *conf);
 381 extern int lxc_ttys_shift_ids(struct lxc_conf *c);
 382 extern int userns_exec_1(struct lxc_conf *conf, int (*fn)(void *), void *data,
 383                          const char *fn_name);
 384 extern int parse_mntopts(const char *mntopts, unsigned long *mntflags,
 385                          char **mntdata);
 386 extern void tmp_proc_unmount(struct lxc_conf *lxc_conf);
 387 extern void remount_all_slave(void);
 388 extern void suggest_default_idmap(void);
 389 extern FILE *make_anonymous_mount_file(struct lxc_list *mount);
 390 extern struct lxc_list *sort_cgroup_settings(struct lxc_list *cgroup_settings);
 391 extern unsigned long add_required_remount_flags(const char *s, const char *d,
 392                                                 unsigned long flags);
 393 extern int run_script(const char *name, const char *section, const char *script,
 394                       ...);
 395
 396 #endif /* __LXC_CONF_H */