src/lxc/lxc_config.c

   1 /*
   2  * lxc: linux Container library
   3  *
   4  * (C) Copyright IBM Corp. 2007, 2008
   5  *
   6  * Authors:
   7  * Daniel Lezcano <dlezcano at fr.ibm.com>
   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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  22  */
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <unistd.h>
  27 #include <errno.h>
  28 #include <sys/types.h>
  29 #include <sys/param.h>
  30 #include <sys/utsname.h>
  31 #include <arpa/inet.h>
  32 #include <netinet/in.h>
  33 #include <net/if.h>
  34
  35 #include <lxc/lxc.h>
  36
  37 typedef int (*file_cb)(char* buffer, void *data);
  38 typedef int (*config_cb)(const char *, char *, struct lxc_conf *);
  39
  40 static int config_tty(const char *, char *, struct lxc_conf *);
  41 static int config_cgroup(const char *, char *, struct lxc_conf *);
  42 static int config_mount(const char *, char *, struct lxc_conf *);
  43 static int config_rootfs(const char *, char *, struct lxc_conf *);
  44 static int config_utsname(const char *, char *, struct lxc_conf *);
  45 static int config_network_type(const char *, char *, struct lxc_conf *);
  46 static int config_network_flags(const char *, char *, struct lxc_conf *);
  47 static int config_network_link(const char *, char *, struct lxc_conf *);
  48 static int config_network_name(const char *, char *, struct lxc_conf *);
  49 static int config_network_hwaddr(const char *, char *, struct lxc_conf *);
  50 static int config_network_ipv4(const char *, char *, struct lxc_conf *);
  51 static int config_network_ipv6(const char *, char *, struct lxc_conf *);
  52
  53 struct config {
  54         char *name;
  55         config_cb cb;
  56 };
  57
  58 static struct config config[] = {
  59
  60         { "lxc.tty",            config_tty            },
  61         { "lxc.cgroup",         config_cgroup         },
  62         { "lxc.mount",          config_mount          },
  63         { "lxc.rootfs",         config_rootfs         },
  64         { "lxc.utsname",        config_utsname        },
  65         { "lxc.network.type",   config_network_type   },
  66         { "lxc.network.flags",  config_network_flags  },
  67         { "lxc.network.link",   config_network_link   },
  68         { "lxc.network.name",   config_network_name   },
  69         { "lxc.network.hwaddr", config_network_hwaddr },
  70         { "lxc.network.ipv4",   config_network_ipv4   },
  71         { "lxc.network.ipv6",   config_network_ipv6   },
  72 };
  73
  74 static const size_t config_size = sizeof(config)/sizeof(struct config);
  75
  76 static struct config *getconfig(const char *key)
  77 {
  78         int i;
  79
  80         for (i = 0; i < config_size; i++)
  81                 if (!strncmp(config[i].name, key,
  82                              strlen(config[i].name)))
  83                         return &config[i];
  84         return NULL;
  85 }
  86
  87 static int is_line_empty(char *line)
  88 {
  89         int i;
  90         size_t len = strlen(line);
  91
  92         for (i = 0; i < len; i++)
  93                 if (line[i] != ' ' && line[i] != '\t' &&
  94                     line[i] != '\n' && line[i] != '\r' &&
  95                     line[i] != '\f' && line[i] != '\0')
  96                         return 0;
  97         return 1;
  98 }
  99
 100 static int char_left_gc(char *buffer, size_t len)
 101 {
 102         int i;
 103         for (i = 0; i < len; i++) {
 104                 if (buffer[i] == ' ' ||
 105                     buffer[i] == '\t')
 106                         continue;
 107                 return i;
 108         }
 109         return 0;
 110 }
 111
 112 static int char_right_gc(char *buffer, size_t len)
 113 {
 114         int i;
 115         for (i = len - 1; i >= 0; i--) {
 116                 if (buffer[i] == ' '  ||
 117                     buffer[i] == '\t' ||
 118                     buffer[i] == '\n' ||
 119                     buffer[i] == '\0')
 120                         continue;
 121                 return i + 1;
 122         }
 123         return 0;
 124 }
 125
 126 static int config_network_type(const char *key, char *value, struct lxc_conf *lxc_conf)
 127 {
 128         struct lxc_list *networks = &lxc_conf->networks;
 129         struct lxc_network *network;
 130         struct lxc_netdev *netdev;
 131         struct lxc_list *list;
 132         struct lxc_list *ndlist;
 133
 134         network = malloc(sizeof(*network));
 135         if (!network) {
 136                 lxc_log_syserror("failed to allocate memory");
 137                 return -1;
 138         }
 139
 140         lxc_list_init(&network->netdev);
 141
 142         netdev = malloc(sizeof(*netdev));
 143         if (!netdev) {
 144                 lxc_log_syserror("failed to allocate memory");
 145                 return -1;
 146         }
 147
 148         lxc_list_init(&netdev->ipv4);
 149         lxc_list_init(&netdev->ipv6);
 150         lxc_list_init(&netdev->route4);
 151         lxc_list_init(&netdev->route6);
 152
 153         ndlist = malloc(sizeof(*ndlist));
 154         if (!ndlist) {
 155                 lxc_log_syserror("failed to allocate memory");
 156                 return -1;
 157         }
 158
 159         ndlist->elem = netdev;
 160
 161         lxc_list_add(&network->netdev, ndlist);
 162
 163         list = malloc(sizeof(*list));
 164         if (!list) {
 165                 lxc_log_syserror("failed to allocate memory");
 166                 return -1;
 167         }
 168
 169         lxc_list_init(list);
 170         list->elem = network;
 171
 172         lxc_list_add(networks, list);
 173
 174         if (!strcmp(value, "veth"))
 175                 network->type = VETH;
 176         else if (!strcmp(value, "macvlan"))
 177                 network->type = MACVLAN;
 178         else if (!strcmp(value, "phys"))
 179                 network->type = PHYS;
 180         else if (!strcmp(value, "empty"))
 181                 network->type = EMPTY;
 182         else {
 183                 lxc_log_error("invalid network type %s", value);
 184                 return -1;
 185         }
 186         return 0;
 187 }
 188
 189 static int config_network_flags(const char *key, char *value, struct lxc_conf *lxc_conf)
 190 {
 191         struct lxc_list *networks = &lxc_conf->networks;
 192         struct lxc_network *network;
 193         struct lxc_netdev *netdev;
 194
 195         if (lxc_list_empty(networks)) {
 196                 lxc_log_error("network is not created for '%s' option", value);
 197                 return -1;
 198         }
 199
 200         network = lxc_list_first_elem(networks);
 201         if (!network) {
 202                 lxc_log_error("no network defined for '%s' option", value);
 203                 return -1;
 204         }
 205
 206         netdev = lxc_list_first_elem(&network->netdev);
 207         netdev->flags |= IFF_UP;
 208         return 0;
 209 }
 210
 211 static int config_network_link(const char *key, char *value, struct lxc_conf *lxc_conf)
 212 {
 213         struct lxc_list *networks = &lxc_conf->networks;
 214         struct lxc_network *network;
 215         struct lxc_netdev *netdev;
 216
 217         if (lxc_list_empty(networks)) {
 218                 lxc_log_error("network is not created for %s", value);
 219                 return -1;
 220         }
 221
 222         network = lxc_list_first_elem(networks);
 223         if (!network) {
 224                 lxc_log_error("no network defined for %s", value);
 225                 return -1;
 226         }
 227
 228         if (strlen(value) > IFNAMSIZ) {
 229                 lxc_log_error("invalid interface name: %s", value);
 230                 return -1;
 231         }
 232
 233         netdev = lxc_list_first_elem(&network->netdev);
 234         netdev->ifname = strdup(value);
 235         return 0;
 236 }
 237
 238 static int config_network_name(const char *key, char *value, struct lxc_conf *lxc_conf)
 239 {
 240         struct lxc_list *networks = &lxc_conf->networks;
 241         struct lxc_network *network;
 242         struct lxc_netdev *netdev;
 243
 244         if (lxc_list_empty(networks)) {
 245                 lxc_log_error("network is not created for %s", value);
 246                 return -1;
 247         }
 248
 249         network = lxc_list_first_elem(networks);
 250         if (!network) {
 251                 lxc_log_error("no network defined for %s", value);
 252                 return -1;
 253         }
 254
 255         if (strlen(value) > IFNAMSIZ) {
 256                 lxc_log_error("invalid interface name: %s", value);
 257                 return -1;
 258         }
 259
 260         netdev = lxc_list_first_elem(&network->netdev);
 261         netdev->newname = strdup(value);
 262         return 0;
 263 }
 264
 265 static int config_network_hwaddr(const char *key, char *value, struct lxc_conf *lxc_conf)
 266 {
 267         struct lxc_list *networks = &lxc_conf->networks;
 268         struct lxc_network *network;
 269         struct lxc_netdev *netdev;
 270
 271         if (lxc_list_empty(networks)) {
 272                 lxc_log_error("network is not created for %s", value);
 273                 return -1;
 274         }
 275
 276         network = lxc_list_first_elem(networks);
 277         if (!network) {
 278                 lxc_log_error("no network defined for %s", value);
 279                 return -1;
 280         }
 281
 282         netdev = lxc_list_first_elem(&network->netdev);
 283         netdev->hwaddr = strdup(value);
 284         return 0;
 285 }
 286
 287 static int config_network_ipv4(const char *key, char *value, struct lxc_conf *lxc_conf)
 288 {
 289         struct lxc_list *networks = &lxc_conf->networks;
 290         struct lxc_network *network;
 291         struct lxc_inetdev *inetdev;
 292         struct lxc_netdev *netdev;
 293         struct lxc_list *list;
 294         char *cursor, *slash, *addr = NULL, *bcast = NULL, *prefix = NULL;
 295
 296         if (lxc_list_empty(networks)) {
 297                 lxc_log_error("network is not created for '%s'", value);
 298                 return -1;
 299         }
 300
 301         network = lxc_list_first_elem(networks);
 302         if (!network) {
 303                 lxc_log_error("no network defined for '%s'", value);
 304                 return -1;
 305         }
 306
 307         netdev = lxc_list_first_elem(&network->netdev);
 308         if (!netdev) {
 309                 lxc_log_error("no netdev defined for '%s'", value);
 310         }
 311
 312         inetdev = malloc(sizeof(*inetdev));
 313         if (!inetdev) {
 314                 lxc_log_syserror("failed to allocate ipv4 address");
 315                 return -1;
 316         }
 317         memset(inetdev, 0, sizeof(*inetdev));
 318
 319         list = malloc(sizeof(*list));
 320         if (!list) {
 321                 lxc_log_syserror("failed to allocate memory");
 322                 return -1;
 323         }
 324
 325         lxc_list_init(list);
 326         list->elem = inetdev;
 327
 328         addr = value;
 329
 330         cursor = strstr(addr, " ");
 331         if (cursor) {
 332                 *cursor = '\0';
 333                 bcast = cursor + 1;
 334         }
 335
 336         slash = strstr(addr, "/");
 337         if (slash) {
 338                 *slash = '\0';
 339                 prefix = slash + 1;
 340         }
 341
 342         if (!addr) {
 343                 lxc_log_error("no address specified");
 344                 return -1;
 345         }
 346
 347         if (!inet_pton(AF_INET, addr, &inetdev->addr)) {
 348                 lxc_log_syserror("invalid ipv4 address: %s", value);
 349                 return -1;
 350         }
 351
 352         if (bcast)
 353                 if (!inet_pton(AF_INET, bcast, &inetdev->bcast)) {
 354                         lxc_log_syserror("invalid ipv4 address: %s", value);
 355                         return -1;
 356                 }
 357
 358         if (prefix)
 359                 inetdev->prefix = atoi(prefix);
 360
 361         lxc_list_add(&netdev->ipv4, list);
 362
 363         return 0;
 364 }
 365
 366 static int config_network_ipv6(const char *key, char *value, struct lxc_conf *lxc_conf)
 367 {
 368         struct lxc_list *networks = &lxc_conf->networks;
 369         struct lxc_network *network;
 370         struct lxc_netdev *netdev;
 371         struct lxc_inet6dev *inet6dev;
 372         struct lxc_list *list;
 373         char *slash;
 374         char *netmask;
 375
 376         if (lxc_list_empty(networks)) {
 377                 lxc_log_error("network is not created for %s", value);
 378                 return -1;
 379         }
 380
 381         network = lxc_list_first_elem(networks);
 382         if (!network) {
 383                 lxc_log_error("no network defined for %s", value);
 384                 return -1;
 385         }
 386
 387         inet6dev = malloc(sizeof(*inet6dev));
 388         if (!inet6dev) {
 389                 lxc_log_syserror("failed to allocate ipv6 address");
 390                 return -1;
 391         }
 392         memset(inet6dev, 0, sizeof(*inet6dev));
 393
 394         list = malloc(sizeof(*list));
 395         if (!list) {
 396                 lxc_log_syserror("failed to allocate memory");
 397                 return -1;
 398         }
 399
 400         lxc_list_init(list);
 401         list->elem = inet6dev;
 402
 403         slash = strstr(value, "/");
 404         if (slash) {
 405                 *slash = '\0';
 406                 netmask = slash + 1;
 407                 inet6dev->prefix = atoi(netmask);
 408         }
 409
 410         if (!inet_pton(AF_INET6, value, &inet6dev->addr)) {
 411                 lxc_log_syserror("invalid ipv6 address: %s", value);
 412                 return -1;
 413         }
 414
 415
 416         netdev = lxc_list_first_elem(&network->netdev);
 417         lxc_list_add(&netdev->ipv6, list);
 418
 419         return 0;
 420 }
 421
 422 static int config_tty(const char *key, char *value, struct lxc_conf *lxc_conf)
 423 {
 424         int nbtty = atoi(value);
 425
 426         lxc_conf->tty = nbtty;
 427
 428         return 0;
 429 }
 430
 431 static int config_cgroup(const char *key, char *value, struct lxc_conf *lxc_conf)
 432 {
 433         char *token = "lxc.cgroup.";
 434         char *subkey;
 435         struct lxc_list *cglist;
 436         struct lxc_cgroup *cgelem;
 437
 438         subkey = strstr(key, token);
 439
 440         if (!subkey)
 441                 return -1;
 442
 443         if (!strlen(subkey))
 444                 return -1;
 445
 446         if (strlen(subkey) == strlen(token))
 447                 return -1;
 448
 449         subkey += strlen(token);
 450
 451         cglist = malloc(sizeof(*cglist));
 452         if (!cglist)
 453                 return -1;
 454
 455         cgelem = malloc(sizeof(*cgelem));
 456         if (!cgelem) {
 457                 free(cglist);
 458                 return -1;
 459         }
 460
 461         cgelem->subsystem = strdup(subkey);
 462         cgelem->value = strdup(value);
 463         cglist->elem = cgelem;
 464
 465         lxc_list_add_tail(&lxc_conf->cgroup, cglist);
 466
 467         return 0;
 468 }
 469
 470 static int config_mount(const char *key, char *value, struct lxc_conf *lxc_conf)
 471 {
 472         if (strlen(value) >= MAXPATHLEN) {
 473                 lxc_log_error("%s path is too long", value);
 474                 return -1;
 475         }
 476
 477         lxc_conf->fstab = strdup(value);
 478         if (!lxc_conf->fstab) {
 479                 lxc_log_syserror("failed to duplicate string %s", value);
 480                 return -1;
 481         }
 482
 483         return 0;
 484 }
 485
 486 static int config_rootfs(const char *key, char *value, struct lxc_conf *lxc_conf)
 487 {
 488         if (strlen(value) >= MAXPATHLEN) {
 489                 lxc_log_error("%s path is too long", value);
 490                 return -1;
 491         }
 492
 493         lxc_conf->rootfs = strdup(value);
 494         if (!lxc_conf->rootfs) {
 495                 lxc_log_syserror("failed to duplicate string %s", value);
 496                 return -1;
 497         }
 498
 499         return 0;
 500 }
 501
 502 static int config_utsname(const char *key, char *value, struct lxc_conf *lxc_conf)
 503 {
 504         struct utsname *utsname;
 505
 506         utsname = malloc(sizeof(*utsname));
 507         if (!utsname) {
 508                 lxc_log_syserror("failed to allocate memory");
 509                 return -1;
 510         }
 511
 512         if (strlen(value) >= sizeof(utsname->nodename)) {
 513                 lxc_log_error("node name '%s' is too long",
 514                               utsname->nodename);
 515                 return -1;
 516         }
 517
 518         strcpy(utsname->nodename, value);
 519         lxc_conf->utsname = utsname;
 520
 521         return 0;
 522 }
 523
 524 static int parse_line(char *buffer, void *data)
 525 {
 526         struct config *config;
 527         char *dot;
 528         char *key;
 529         char *value;
 530
 531         if (is_line_empty(buffer))
 532                 return 0;
 533
 534         buffer += char_left_gc(buffer, strlen(buffer));
 535         if (buffer[0] == '#')
 536                 return 0;
 537
 538         dot = strstr(buffer, "=");
 539         if (!dot) {
 540                 lxc_log_error("invalid configuration line: %s", buffer);
 541                 return -1;
 542         }
 543
 544         *dot = '\0';
 545         value = dot + 1;
 546
 547         key = buffer;
 548         key[char_right_gc(key, strlen(key))] = '\0';
 549
 550         value += char_left_gc(value, strlen(value));
 551         value[char_right_gc(value, strlen(value))] = '\0';
 552
 553         config = getconfig(key);
 554         if (!config) {
 555                 lxc_log_error("unknow key %s", key);
 556                 return -1;
 557         }
 558
 559         return config->cb(key, value, data);
 560 }
 561
 562 static int file_for_each_line(const char *file, file_cb callback, void *data)
 563 {
 564         char buffer[MAXPATHLEN];
 565         size_t len = sizeof(buffer);
 566         FILE *f;
 567         int err = -1;
 568
 569         f = fopen(file, "r");
 570         if (!f) {
 571                 lxc_log_syserror("failed to open %s", file);
 572                 return -1;
 573         }
 574
 575         while (fgets(buffer, len, f))
 576                 if (callback(buffer, data))
 577                         goto out;
 578         err = 0;
 579 out:
 580         fclose(f);
 581         return err;
 582 }
 583
 584 int lxc_config_read(const char *file, struct lxc_conf *conf)
 585 {
 586         return file_for_each_line(file, parse_line, conf);
 587 }
 588
 589 int lxc_config_init(struct lxc_conf *conf)
 590 {
 591         conf->rootfs = NULL;
 592         conf->fstab = NULL;
 593         conf->utsname = NULL;
 594         conf->tty = 0;
 595         lxc_list_init(&conf->cgroup);
 596         lxc_list_init(&conf->networks);
 597         return 0;
 598 }