block.c

   1 /*
   2  * Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
   3  * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU Lesser General Public License version 2.1
   7  * as published by the Free Software Foundation
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #include <stdio.h>
  16 #include <unistd.h>
  17 #include <syslog.h>
  18 #include <libgen.h>
  19 #include <glob.h>
  20
  21 #include <sys/stat.h>
  22 #include <sys/types.h>
  23 #include <sys/swap.h>
  24 #include <sys/mount.h>
  25
  26 #include <uci.h>
  27 #include <uci_blob.h>
  28
  29 #include <libubox/list.h>
  30 #include <libubox/vlist.h>
  31 #include <libubox/blobmsg_json.h>
  32 #include <libubox/avl-cmp.h>
  33
  34 #include "libblkid-tiny/libblkid-tiny.h"
  35
  36 enum {
  37         TYPE_MOUNT,
  38         TYPE_SWAP,
  39 };
  40
  41 struct mount {
  42         struct vlist_node node;
  43         int type;
  44
  45         char *target;
  46         char *path;
  47         char *options;
  48         char *uuid;
  49         char *label;
  50         int disabled_fsck;
  51         unsigned int prio;
  52 };
  53
  54 static struct vlist_tree mounts;
  55 static struct blob_buf b;
  56 static LIST_HEAD(devices);
  57
  58 enum {
  59         MOUNT_UUID,
  60         MOUNT_LABEL,
  61         MOUNT_ENABLE,
  62         MOUNT_TARGET,
  63         MOUNT_OPTIONS,
  64         __MOUNT_MAX
  65 };
  66
  67 static const struct blobmsg_policy mount_policy[__MOUNT_MAX] = {
  68         [MOUNT_UUID] = { .name = "uuid", .type = BLOBMSG_TYPE_STRING },
  69         [MOUNT_LABEL] = { .name = "label", .type = BLOBMSG_TYPE_STRING },
  70         [MOUNT_TARGET] = { .name = "target", .type = BLOBMSG_TYPE_STRING },
  71         [MOUNT_OPTIONS] = { .name = "options", .type = BLOBMSG_TYPE_STRING },
  72         [MOUNT_ENABLE] = { .name = "enabled", .type = BLOBMSG_TYPE_INT32 },
  73 };
  74
  75 static const struct uci_blob_param_list mount_attr_list = {
  76         .n_params = __MOUNT_MAX,
  77         .params = mount_policy,
  78 };
  79
  80 enum {
  81         SWAP_ENABLE,
  82         SWAP_UUID,
  83         SWAP_PRIO,
  84         __SWAP_MAX
  85 };
  86
  87 static const struct blobmsg_policy swap_policy[__SWAP_MAX] = {
  88         [SWAP_ENABLE] = { .name = "enabled", .type = BLOBMSG_TYPE_INT32 },
  89         [SWAP_UUID] = { .name = "uuid", .type = BLOBMSG_TYPE_STRING },
  90         [SWAP_PRIO] = { .name = "priority", .type = BLOBMSG_TYPE_INT32 },
  91 };
  92
  93 static const struct uci_blob_param_list swap_attr_list = {
  94         .n_params = __SWAP_MAX,
  95         .params = swap_policy,
  96 };
  97
  98 static char *blobmsg_get_strdup(struct blob_attr *attr)
  99 {
 100         if (!attr)
 101                 return NULL;
 102
 103         return strdup(blobmsg_get_string(attr));
 104 }
 105
 106 static int mount_add(struct uci_section *s)
 107 {
 108         struct blob_attr *tb[__MOUNT_MAX] = { 0 };
 109         struct mount *m;
 110
 111         blob_buf_init(&b, 0);
 112         uci_to_blob(&b, s, &mount_attr_list);
 113         blobmsg_parse(mount_policy, __MOUNT_MAX, tb, blob_data(b.head), blob_len(b.head));
 114
 115         if (!tb[MOUNT_LABEL] && !tb[MOUNT_UUID])
 116                 return -1;
 117
 118         if (!tb[MOUNT_TARGET])
 119                 return -1;
 120
 121         m = malloc(sizeof(struct mount));
 122         m->type = TYPE_MOUNT;
 123         m->uuid = blobmsg_get_strdup(tb[MOUNT_UUID]);
 124         m->label = blobmsg_get_strdup(tb[MOUNT_LABEL]);
 125         m->target = blobmsg_get_strdup(tb[MOUNT_TARGET]);
 126         m->options = blobmsg_get_strdup(tb[MOUNT_OPTIONS]);
 127
 128         if ((!tb[MOUNT_ENABLE]) || blobmsg_get_u32(tb[MOUNT_ENABLE]))
 129                 vlist_add(&mounts, &m->node, m->target);
 130
 131         return 0;
 132 }
 133
 134 static int swap_add(struct uci_section *s)
 135 {
 136         struct blob_attr *tb[__SWAP_MAX] = { 0 };
 137         struct mount *m;
 138
 139         blob_buf_init(&b, 0);
 140         uci_to_blob(&b, s, &swap_attr_list);
 141         blobmsg_parse(swap_policy, __SWAP_MAX, tb, blob_data(b.head), blob_len(b.head));
 142
 143         if (!tb[SWAP_UUID])
 144                 return -1;
 145
 146         m = malloc(sizeof(struct mount));
 147         memset(m, 0, sizeof(struct mount));
 148         m->type = TYPE_SWAP;
 149         m->uuid = blobmsg_get_strdup(tb[SWAP_UUID]);
 150         if (tb[SWAP_PRIO])
 151                 m->prio = blobmsg_get_u32(tb[SWAP_PRIO]);
 152         if (m->prio)
 153                 m->prio = ((m->prio << SWAP_FLAG_PRIO_SHIFT) & SWAP_FLAG_PRIO_MASK) | SWAP_FLAG_PREFER;
 154
 155         if ((!tb[SWAP_ENABLE]) || blobmsg_get_u32(tb[SWAP_ENABLE]))
 156                 vlist_add(&mounts, &m->node, m->uuid);
 157
 158         return 0;
 159 }
 160
 161 static struct mount* find_swap(const char *uuid)
 162 {
 163         struct mount *m;
 164
 165         if (!uuid)
 166                 return NULL;
 167
 168         vlist_for_each_element(&mounts, m, node)
 169                 if ((m->type == TYPE_SWAP) && m->uuid && !strcmp(m->uuid, uuid))
 170                         return m;
 171
 172         return NULL;
 173 }
 174
 175 static struct mount* find_block(const char *uuid, const char *label, const char *target)
 176 {
 177         struct mount *m;
 178
 179         vlist_for_each_element(&mounts, m, node) {
 180                 if ((m->type == TYPE_MOUNT) && m->uuid && uuid && !strcmp(m->uuid, uuid))
 181                         return m;
 182                 if ((m->type == TYPE_MOUNT) && m->label && label && !strcmp(m->label, label))
 183                         return m;
 184                 if ((m->type == TYPE_MOUNT) && target && !strcmp(m->target, target))
 185                         return m;
 186         }
 187
 188         return NULL;
 189 }
 190
 191 static void mounts_update(struct vlist_tree *tree, struct vlist_node *node_new,
 192                           struct vlist_node *node_old)
 193 {
 194 }
 195
 196 static int config_load(char *cfg)
 197 {
 198         struct uci_context *ctx;
 199         struct uci_package *pkg;
 200         struct uci_element *e;
 201
 202         vlist_init(&mounts, avl_strcmp, mounts_update);
 203
 204         ctx = uci_alloc_context();
 205         if (cfg) {
 206                 char path[32];
 207                 snprintf(path, 32, "%s/etc/config", cfg);
 208                 uci_set_confdir(ctx, path);
 209         }
 210
 211         if (uci_load(ctx, "fstab", &pkg))
 212                 return -1;
 213
 214         vlist_update(&mounts);
 215         uci_foreach_element(&pkg->sections, e) {
 216                 struct uci_section *s = uci_to_section(e);
 217
 218                 if (!strcmp(s->type, "mount"))
 219                         mount_add(s);
 220                 if (!strcmp(s->type, "swap"))
 221                         swap_add(s);
 222         }
 223         vlist_flush(&mounts);
 224
 225         return 0;
 226 }
 227
 228 static int _cache_load(const char *path)
 229 {
 230         int gl_flags = GLOB_NOESCAPE | GLOB_MARK;
 231         int j;
 232         glob_t gl;
 233
 234         if (glob(path, gl_flags, NULL, &gl) < 0)
 235                 return -1;
 236
 237         for (j = 0; j < gl.gl_pathc; j++) {
 238                 struct blkid_struct_probe *pr = malloc(sizeof(struct blkid_struct_probe));
 239                 memset(pr, 0, sizeof(struct blkid_struct_probe));
 240                 probe_block(gl.gl_pathv[j], pr);
 241                 if (pr->err)
 242                         free(pr);
 243                 else
 244                         list_add_tail(&pr->list, &devices);
 245         }
 246
 247         globfree(&gl);
 248
 249         return 0;
 250 }
 251
 252 static void cache_load(int mtd)
 253 {
 254         if (mtd)
 255                 _cache_load("/dev/mtdblock*");
 256         _cache_load("/dev/sd*");
 257 }
 258
 259 static int print_block_info(struct blkid_struct_probe *pr)
 260 {
 261         printf("%s:", pr->dev);
 262         if (pr->uuid[0])
 263                 printf(" UUID=\"%s\"", pr->uuid);
 264
 265         if (pr->label[0])
 266                 printf(" LABEL=\"%s\"", pr->label);
 267
 268         if (pr->name[0])
 269                 printf(" NAME=\"%s\"", pr->name);
 270
 271         if (pr->version[0])
 272                 printf(" VERSION=\"%s\"", pr->version);
 273
 274         printf(" TYPE=\"%s\"\n", pr->id->name);
 275
 276         return 0;
 277 }
 278
 279 static int print_block_uci(struct blkid_struct_probe *pr)
 280 {
 281         if (!pr->uuid[0])
 282                 return 0;
 283
 284         if (!strcmp(pr->id->name, "swap")) {
 285                 printf("config 'swap'\n");
 286         } else {
 287                 printf("config 'mount'\n");
 288                 printf("\toption\ttarget\t'/mnt/%s'\n", basename(pr->dev));
 289         }
 290         printf("\toption\tuuid\t'%s'\n", pr->uuid);
 291         printf("\toption\tenabled\t'0'\n\n");
 292
 293         return 0;
 294 }
 295
 296 static struct blkid_struct_probe* find_block_info(char *uuid, char *label, char *path)
 297 {
 298         struct blkid_struct_probe *pr = NULL;
 299
 300         if (uuid)
 301                 list_for_each_entry(pr, &devices, list)
 302                         if (!strcmp(pr->uuid, uuid))
 303                                 return pr;
 304
 305         if (label)
 306                 list_for_each_entry(pr, &devices, list)
 307                         if (strcmp(pr->label, label))
 308                                 return pr;
 309
 310         if (path)
 311                 list_for_each_entry(pr, &devices, list)
 312                         if (!strcmp(pr->dev, path))
 313                                 return pr;
 314
 315         return NULL;
 316 }
 317
 318 static char* find_mount_point(char *block)
 319 {
 320         FILE *fp = fopen("/proc/mounts", "r");
 321         static char line[256];
 322         int len = strlen(block);
 323         char *point = NULL;
 324
 325         if(!fp)
 326                 return NULL;
 327
 328         while (fgets(line, sizeof(line), fp)) {
 329                 if (!strncmp(line, block, len)) {
 330                         char *p = &line[len + 1];
 331                         char *t = strstr(p, " ");
 332
 333                         if (!t)
 334                                 return NULL;
 335                         *t = '\0';
 336                         point = p;
 337                         break;
 338                 }
 339         }
 340
 341         fclose(fp);
 342
 343         return point;
 344 }
 345
 346 static void mkdir_p(char *dir)
 347 {
 348         char *l = strrchr(dir, '/');
 349
 350         if (l) {
 351                 *l = '\0';
 352                 mkdir_p(dir);
 353                 *l = '/';
 354                 mkdir(dir, 0755);
 355         }
 356 }
 357
 358 static int main_hotplug(int argc, char **argv)
 359 {
 360         struct mount *m;
 361         char path[256];
 362         char *action, *device, *mount_point;
 363         struct blkid_struct_probe *pr;
 364
 365         action = getenv("ACTION");
 366         device = getenv("DEVNAME");
 367
 368         if (!action || !device)
 369                 return -1;
 370         snprintf(path, sizeof(path), "/dev/%s", device);
 371
 372         if (!strcmp(action, "remove")) {
 373                 int err = 0;
 374                 mount_point = find_mount_point(path);
 375                 if (mount_point)
 376                         err = umount2(mount_point, MNT_DETACH);
 377
 378                 if (err)
 379                         fprintf(stderr, "unmount of %s failed (%d) - %s\n",
 380                                         mount_point, err, strerror(err));
 381
 382                 return 0;
 383         } else if (strcmp(action, "add")) {
 384                 fprintf(stderr, "Unkown action %s\n", action);
 385
 386                 return -1;
 387         }
 388
 389         if (config_load(NULL))
 390                 return -1;
 391         cache_load(0);
 392
 393         pr = find_block_info(NULL, NULL, path);
 394         if (!pr && pr->uuid) {
 395                 fprintf(stderr, "failed to read blockinfo for %s\n", path);
 396                 return -1;
 397         }
 398
 399         m = find_swap(pr->uuid);
 400         if (m) {
 401                 if (!strcmp(action, "add"))
 402                         swapon(path, m->prio);
 403                 else
 404                         swapoff(path);
 405         } else {
 406                 m = find_block(pr->uuid, pr->label, NULL);
 407                 if (m && strcmp(m->target, "/")) {
 408                         int err = 0;
 409
 410                         mkdir_p(m->target);
 411                         err = mount(path, m->target, pr->id->name, 0, (m->options) ? (m->options) : (""));
 412                         if (err)
 413                                 fprintf(stderr, "mounting %s (%s) as %s failed (%d) - %s\n",
 414                                                 path, pr->id->name, m->target, err, strerror(err));
 415                 }
 416         }
 417
 418         return 0;
 419 }
 420
 421 static int find_block_mtd(char *name, char *part, int plen)
 422 {
 423         FILE *fp = fopen("/proc/mtd", "r");
 424         static char line[256];
 425         char *index = NULL;
 426
 427         if(!fp)
 428                 return -1;
 429
 430         while (!index && fgets(line, sizeof(line), fp)) {
 431                 if (strstr(line, name)) {
 432                         char *eol = strstr(line, ":");
 433
 434                         if (!eol)
 435                                 continue;
 436
 437                         *eol = '\0';
 438                         index = &line[3];
 439                 }
 440         }
 441
 442         fclose(fp);
 443
 444         if (!index)
 445                 return -1;
 446
 447         snprintf(part, plen, "/dev/mtdblock%s", index);
 448
 449         return 0;
 450 }
 451
 452 static int mount_extroot(char *path, char *cfg)
 453 {
 454         struct blkid_struct_probe *pr;
 455         struct mount *m;
 456         int err = -1;
 457
 458         if (config_load(cfg))
 459                 return 2;
 460
 461         m = find_block(NULL, NULL, "/");
 462         if (!m)
 463                 return 1;
 464
 465         pr = find_block_info(m->uuid, m->label, NULL);
 466         if (pr) {
 467                 mkdir_p(path);
 468                 err = mount(pr->dev, path, pr->id->name, 0, (m->options) ? (m->options) : (""));
 469
 470                 if (err)
 471                         fprintf(stderr, "mounting %s (%s) as %s failed (%d) - %s\n",
 472                                         pr->dev, pr->id->name, path, err, strerror(err));
 473         }
 474
 475         return err;
 476 }
 477
 478 static int main_extroot(int argc, char **argv)
 479 {
 480         struct blkid_struct_probe *pr;
 481         char fs[32] = { 0 };
 482         char fs_data[32] = { 0 };
 483         int err = 1;
 484         char extroot[] = "/tmp/overlay";
 485
 486         if (!getenv("PREINIT"))
 487                 return -1;
 488
 489         if (argc != 2) {
 490                 fprintf(stderr, "Usage: block extroot mountpoint\n");
 491                 return 1;
 492         }
 493
 494         mkblkdev();
 495         cache_load(1);
 496
 497         find_block_mtd("rootfs", fs, sizeof(fs));
 498         if (!fs[0])
 499                 return 2;
 500
 501         pr = find_block_info(NULL, NULL, fs);
 502         if (!pr || strcmp(pr->id->name, "squashfs"))
 503                 return 3;
 504
 505         find_block_mtd("rootfs_data", fs_data, sizeof(fs_data));
 506         if (fs_data[0]) {
 507                 pr = find_block_info(NULL, NULL, fs_data);
 508                 if (pr && !strcmp(pr->id->name, "jffs2")) {
 509                         char cfg[] = "/tmp/jffs_cfg";
 510
 511                         mkdir_p(cfg);
 512                         if (!mount(fs_data, cfg, "jffs2", MS_NOATIME, NULL)) {
 513                                 err = mount_extroot(extroot, cfg);
 514                                 umount2(cfg, MNT_DETACH);
 515                         }
 516                         if (err)
 517                                 rmdir(extroot);
 518                         rmdir(cfg);
 519                         return err;
 520                 }
 521         }
 522
 523         err = mount_extroot(extroot, NULL);
 524
 525         return err;
 526 }
 527
 528 static int main_detect(int argc, char **argv)
 529 {
 530         struct blkid_struct_probe *pr;
 531
 532         cache_load(0);
 533         list_for_each_entry(pr, &devices, list)
 534                 print_block_uci(pr);
 535
 536         return 0;
 537 }
 538
 539 static int main_info(int argc, char **argv)
 540 {
 541         int i;
 542         struct blkid_struct_probe *pr;
 543
 544         cache_load(1);
 545         if (argc == 2) {
 546                 list_for_each_entry(pr, &devices, list)
 547                         print_block_info(pr);
 548
 549                 return 0;
 550         };
 551
 552         for (i = 2; i < argc; i++) {
 553                 struct stat s;
 554
 555                 if (stat(argv[i], &s)) {
 556                         fprintf(stderr, "failed to stat %s\n", argv[i]);
 557                         continue;
 558                 }
 559                 if (!S_ISBLK(s.st_mode)) {
 560                         fprintf(stderr, "%s is not a block device\n", argv[i]);
 561                         continue;
 562                 }
 563                 pr = find_block_info(NULL, NULL, argv[i]);
 564                 if (pr)
 565                         print_block_info(pr);
 566         }
 567
 568         return 0;
 569 }
 570
 571 static int main_swapon(int argc, char **argv)
 572 {
 573         if (argc != 2) {
 574                 fprintf(stderr, "Usage: swapoff [-a] [DEVICE]\n\nStop swapping on DEVICE\n\n\t-a      Stop swapping on all swap devices\n");
 575                 return -1;
 576         }
 577
 578         if (!strcmp(argv[1], "-a")) {
 579                 struct blkid_struct_probe *pr;
 580
 581                 cache_load(0);
 582                 list_for_each_entry(pr, &devices, list) {
 583                         if (strcmp(pr->id->name, "swap"))
 584                                 continue;
 585                         if (swapon(pr->dev, 0))
 586                                 fprintf(stderr, "failed to swapon %s\n", pr->dev);
 587                 }
 588         } else {
 589                 struct stat s;
 590                 int err;
 591
 592                 if (stat(argv[1], &s) || !S_ISBLK(s.st_mode)) {
 593                         fprintf(stderr, "%s is not a block device\n", argv[1]);
 594                         return -1;
 595                 }
 596                 err = swapon(argv[1], 0);
 597                 if (err) {
 598                         fprintf(stderr, "failed to swapon %s (%d)\n", argv[1], err);
 599                         return err;
 600                 }
 601         }
 602
 603         return 0;
 604 }
 605
 606 static int main_swapoff(int argc, char **argv)
 607 {
 608         if (argc != 2) {
 609                 fprintf(stderr, "Usage: swapoff [-a] [DEVICE]\n\nStop swapping on DEVICE\n\n\t-a      Stop swapping on all swap devices\n");
 610                 return -1;
 611         }
 612
 613         if (!strcmp(argv[1], "-a")) {
 614                 FILE *fp = fopen("/proc/swaps", "r");
 615                 char line[256];
 616
 617                 if (!fp) {
 618                         fprintf(stderr, "failed to open /proc/swaps\n");
 619                         return -1;
 620                 }
 621                 fgets(line, sizeof(line), fp);
 622                 while (fgets(line, sizeof(line), fp)) {
 623                         char *end = strchr(line, ' ');
 624                         int err;
 625
 626                         if (!end)
 627                                 continue;
 628                         *end = '\0';
 629                         err = swapoff(line);
 630                         if (err)
 631                                 fprintf(stderr, "failed to swapoff %s (%d)\n", line, err);
 632                 }
 633                 fclose(fp);
 634         } else {
 635                 struct stat s;
 636                 int err;
 637
 638                 if (stat(argv[1], &s) || !S_ISBLK(s.st_mode)) {
 639                         fprintf(stderr, "%s is not a block device\n", argv[1]);
 640                         return -1;
 641                 }
 642                 err = swapoff(argv[1]);
 643                 if (err) {
 644                         fprintf(stderr, "fsiled to swapoff %s (%d)\n", argv[1], err);
 645                         return err;
 646                 }
 647         }
 648
 649         return 0;
 650 }
 651
 652 int main(int argc, char **argv)
 653 {
 654         char *base = basename(*argv);
 655
 656         if (!strcmp(base, "swapon"))
 657                 return main_swapon(argc, argv);
 658
 659         if (!strcmp(base, "swapoff"))
 660                 return main_swapoff(argc, argv);
 661
 662         if ((argc > 1) && !strcmp(base, "block")) {
 663                 if (!strcmp(argv[1], "info"))
 664                         return main_info(argc, argv);
 665
 666                 if (!strcmp(argv[1], "detect"))
 667                         return main_detect(argc, argv);
 668
 669                 if (!strcmp(argv[1], "hotplug"))
 670                         return main_hotplug(argc, argv);
 671
 672                 if (!strcmp(argv[1], "extroot"))
 673                         return main_extroot(argc, argv);
 674         }
 675
 676         fprintf(stderr, "Usage: block <info|detect>\n");
 677
 678         return -1;
 679 }