git.ozlabs.org Git - petitboot/blob - discover/boot.c

   1
   2 #if defined(HAVE_CONFIG_H)
   3 #include "config.h"
   4 #endif
   5
   6 #include <stdbool.h>
   7 #include <stdlib.h>
   8 #include <assert.h>
   9 #include <dirent.h>
  10 #include <string.h>
  11 #include <fcntl.h>
  12 #include <sys/types.h>
  13
  14 #include <log/log.h>
  15 #include <pb-protocol/pb-protocol.h>
  16 #include <process/process.h>
  17 #include <system/system.h>
  18 #include <talloc/talloc.h>
  19 #include <url/url.h>
  20 #include <util/util.h>
  21 #include <i18n/i18n.h>
  22
  23 #include "device-handler.h"
  24 #include "boot.h"
  25 #include "paths.h"
  26 #include "resource.h"
  27 #include "platform.h"
  28
  29 #include <security/gpg.h>
  30
  31 static const char *boot_hook_dir = PKG_SYSCONF_DIR "/boot.d";
  32 enum {
  33         BOOT_HOOK_EXIT_OK       = 0,
  34         BOOT_HOOK_EXIT_UPDATE   = 2,
  35 };
  36
  37 static void __attribute__((format(__printf__, 4, 5))) update_status(
  38                 boot_status_fn fn, void *arg, int type, char *fmt, ...)
  39 {
  40         struct status status;
  41         va_list ap;
  42
  43         va_start(ap, fmt);
  44         status.message = talloc_vasprintf(NULL, fmt, ap);
  45         va_end(ap);
  46
  47         status.type = type;
  48         status.backlog = false;
  49
  50         pb_debug("boot status: [%d] %s\n", type, status.message);
  51
  52         fn(arg, &status);
  53
  54         talloc_free(status.message);
  55 }
  56
  57 /**
  58  * kexec_load - kexec load helper.
  59  */
  60 static int kexec_load(struct boot_task *boot_task)
  61 {
  62         struct process *process;
  63         char *s_initrd = NULL;
  64         char *s_args = NULL;
  65         const char *argv[7];
  66         char *s_dtb = NULL;
  67         const char **p;
  68         int result;
  69
  70
  71         boot_task->local_initrd_override = NULL;
  72         boot_task->local_dtb_override = NULL;
  73         boot_task->local_image_override = NULL;
  74
  75         if ((result = gpg_validate_boot_files(boot_task))) {
  76                 if (result == KEXEC_LOAD_DECRYPTION_FALURE) {
  77                         pb_log("%s: Aborting kexec due to"
  78                                 " decryption failure\n", __func__);
  79                         goto abort_kexec;
  80                 }
  81                 if (result == KEXEC_LOAD_SIGNATURE_FAILURE) {
  82                         pb_log("%s: Aborting kexec due to signature"
  83                                 " verification failure\n", __func__);
  84                         goto abort_kexec;
  85                 }
  86         }
  87
  88         const char* local_initrd = (boot_task->local_initrd_override) ?
  89                 boot_task->local_initrd_override : boot_task->local_initrd;
  90         const char* local_dtb = (boot_task->local_dtb_override) ?
  91                 boot_task->local_dtb_override : boot_task->local_dtb;
  92         const char* local_image = (boot_task->local_image_override) ?
  93                 boot_task->local_image_override : boot_task->local_image;
  94
  95         process = process_create(boot_task);
  96         if (!process) {
  97                 pb_log("%s: failed to create process\n", __func__);
  98                 return -1;
  99         }
 100
 101         process->path = pb_system_apps.kexec;
 102         process->argv = argv;
 103         process->keep_stdout = true;
 104         process->add_stderr = true;
 105
 106         p = argv;
 107         *p++ = pb_system_apps.kexec;    /* 1 */
 108         *p++ = "-l";                    /* 2 */
 109
 110         if (local_initrd) {
 111                 s_initrd = talloc_asprintf(boot_task, "--initrd=%s",
 112                                 local_initrd);
 113                 assert(s_initrd);
 114                 *p++ = s_initrd;         /* 3 */
 115         }
 116
 117         if (local_dtb) {
 118                 s_dtb = talloc_asprintf(boot_task, "--dtb=%s",
 119                                                 local_dtb);
 120                 assert(s_dtb);
 121                 *p++ = s_dtb;            /* 4 */
 122         }
 123
 124         s_args = talloc_asprintf(boot_task, "--append=%s",
 125                                 boot_task->args ?: "\"\"");
 126         assert(s_args);
 127         *p++ = s_args;          /* 5 */
 128
 129         *p++ = local_image;             /* 6 */
 130         *p++ = NULL;                    /* 7 */
 131
 132         result = process_run_sync(process);
 133         if (result) {
 134                 pb_log("%s: failed to run process\n", __func__);
 135                 goto abort_kexec;
 136         }
 137
 138         result = process->exit_status;
 139
 140         if (result) {
 141                 pb_log("%s: failed: (%d)\n", __func__, result);
 142                 update_status(boot_task->status_fn, boot_task->status_arg,
 143                                 STATUS_ERROR, "%s", process->stdout_buf);
 144         }
 145
 146 abort_kexec:
 147         gpg_validate_boot_files_cleanup(boot_task);
 148
 149         return result;
 150 }
 151
 152 /**
 153  * kexec_reboot - Helper to boot the new kernel.
 154  *
 155  * Must only be called after a successful call to kexec_load().
 156  */
 157
 158 static int kexec_reboot(struct boot_task *task)
 159 {
 160         int result;
 161
 162         /* First try running shutdown.  Init scripts should run 'exec -e' */
 163         result = process_run_simple(task, pb_system_apps.shutdown, "-r",
 164                         "now", NULL);
 165
 166         /* On error, force a kexec with the -e option */
 167         if (result) {
 168                 result = process_run_simple(task, pb_system_apps.kexec,
 169                                                 "-e", NULL);
 170         }
 171
 172         if (result)
 173                 pb_log("%s: failed: (%d)\n", __func__, result);
 174
 175         /* okay, kexec -e -f */
 176         if (result) {
 177                 result = process_run_simple(task, pb_system_apps.kexec,
 178                                                 "-e", "-f", NULL);
 179         }
 180
 181         if (result)
 182                 pb_log("%s: failed: (%d)\n", __func__, result);
 183
 184
 185         return result;
 186 }
 187
 188 static void boot_hook_update_param(void *ctx, struct boot_task *task,
 189                 const char *name, const char *value)
 190 {
 191         struct p {
 192                 const char *name;
 193                 const char **p;
 194         } *param, params[] = {
 195                 { "boot_image",         &task->local_image },
 196                 { "boot_initrd",        &task->local_initrd },
 197                 { "boot_dtb",           &task->local_dtb },
 198                 { "boot_args",          &task->args },
 199                 { NULL, NULL },
 200         };
 201
 202         for (param = params; param->name; param++) {
 203                 if (strcmp(param->name, name))
 204                         continue;
 205
 206                 *param->p = talloc_strdup(ctx, value);
 207                 return;
 208         }
 209 }
 210
 211 static void boot_hook_update(struct boot_task *task, const char *hookname,
 212                 char *buf)
 213 {
 214         char *line, *name, *val, *sep;
 215         char *saveptr = NULL;
 216
 217         for (;; buf = NULL) {
 218
 219                 line = strtok_r(buf, "\n", &saveptr);
 220                 if (!line)
 221                         break;
 222
 223                 sep = strchr(line, '=');
 224                 if (!sep)
 225                         continue;
 226
 227                 *sep = '\0';
 228                 name = line;
 229                 val = sep + 1;
 230
 231                 boot_hook_update_param(task, task, name, val);
 232
 233                 pb_log("boot hook %s specified %s=%s\n",
 234                                 hookname, name, val);
 235         }
 236 }
 237
 238 static void boot_hook_setenv(struct boot_task *task)
 239 {
 240         unsetenv("boot_image");
 241         unsetenv("boot_initrd");
 242         unsetenv("boot_dtb");
 243         unsetenv("boot_args");
 244         unsetenv("boot_console");
 245
 246         setenv("boot_image", task->local_image, 1);
 247         if (task->local_initrd)
 248                 setenv("boot_initrd", task->local_initrd, 1);
 249         if (task->local_dtb)
 250                 setenv("boot_dtb", task->local_dtb, 1);
 251         if (task->args)
 252                 setenv("boot_args", task->args, 1);
 253         if (task->boot_console)
 254                 setenv("boot_console", task->boot_console, 1);
 255 }
 256
 257 static int hook_filter(const struct dirent *dirent)
 258 {
 259         return dirent->d_type == DT_REG || dirent->d_type == DT_LNK;
 260 }
 261
 262 static int hook_cmp(const struct dirent **a, const struct dirent **b)
 263 {
 264         return strcmp((*a)->d_name, (*b)->d_name);
 265 }
 266
 267 static void run_boot_hooks(struct boot_task *task)
 268 {
 269         struct dirent **hooks;
 270         int i, n;
 271
 272         n = scandir(boot_hook_dir, &hooks, hook_filter, hook_cmp);
 273         if (n < 1)
 274                 return;
 275
 276         update_status(task->status_fn, task->status_arg, STATUS_INFO,
 277                         _("Running boot hooks"));
 278
 279         boot_hook_setenv(task);
 280
 281         for (i = 0; i < n; i++) {
 282                 const char *argv[2] = { NULL, NULL };
 283                 struct process *process;
 284                 char *path;
 285                 int rc;
 286
 287                 path = join_paths(task, boot_hook_dir, hooks[i]->d_name);
 288
 289                 if (access(path, X_OK)) {
 290                         talloc_free(path);
 291                         continue;
 292                 }
 293
 294                 process = process_create(task);
 295
 296                 argv[0] = path;
 297                 process->path = path;
 298                 process->argv = argv;
 299                 process->keep_stdout = true;
 300
 301                 pb_log("running boot hook %s\n", hooks[i]->d_name);
 302
 303                 rc = process_run_sync(process);
 304                 if (rc) {
 305                         pb_log("boot hook exec failed!\n");
 306
 307                 } else if (WIFEXITED(process->exit_status) &&
 308                            WEXITSTATUS(process->exit_status)
 309                                 == BOOT_HOOK_EXIT_UPDATE) {
 310                         /* if the hook returned with BOOT_HOOK_EXIT_UPDATE,
 311                          * then we process stdout to look for updated params
 312                          */
 313                         boot_hook_update(task, hooks[i]->d_name,
 314                                         process->stdout_buf);
 315                         boot_hook_setenv(task);
 316                 }
 317
 318                 process_release(process);
 319                 talloc_free(path);
 320         }
 321
 322         free(hooks);
 323 }
 324
 325 static bool load_pending(struct load_url_result *result)
 326 {
 327         return result && result->status == LOAD_ASYNC;
 328 }
 329
 330 static int check_load(struct boot_task *task, const char *name,
 331                 struct load_url_result *result)
 332 {
 333         if (!result)
 334                 return 0;
 335
 336         if (result->status != LOAD_ERROR) {
 337                 update_status(task->status_fn, task->status_arg,
 338                                 STATUS_ERROR,
 339                                 _("Loaded %s from %s"), name,
 340                                 pb_url_to_string(result->url));
 341                 return 0;
 342         }
 343
 344         update_status(task->status_fn, task->status_arg,
 345                         STATUS_ERROR,
 346                         _("Couldn't load %s from %s"), name,
 347                         pb_url_to_string(result->url));
 348         return -1;
 349 }
 350
 351 static void cleanup_load(struct load_url_result *result)
 352 {
 353         if (!result)
 354                 return;
 355         if (result->status != LOAD_OK)
 356                 return;
 357         if (!result->cleanup_local)
 358                 return;
 359         unlink(result->local);
 360 }
 361
 362 static void cleanup_cancellations(struct boot_task *task,
 363                 struct load_url_result *cur_result)
 364 {
 365         struct load_url_result *result, **results[] = {
 366                 &task->image, &task->initrd, &task->dtb,
 367         };
 368         bool pending = false;
 369         unsigned int i;
 370
 371         for (i = 0; i < ARRAY_SIZE(results); i++) {
 372                 result = *results[i];
 373
 374                 if (!result)
 375                         continue;
 376
 377                 /* We need to cleanup and free any completed loads */
 378                 if (result == cur_result || result->status == LOAD_OK
 379                                 || result->status == LOAD_ERROR) {
 380                         cleanup_load(result);
 381                         talloc_free(result);
 382                         *results[i] = NULL;
 383
 384                 /* ... and cancel any pending loads, which we'll free in
 385                  * the completion callback */
 386                 } else if (result->status == LOAD_ASYNC) {
 387                         load_url_async_cancel(result);
 388                         pending = true;
 389
 390                 /* if we're waiting for a cancellation, we still need to
 391                  * wait for the completion before freeing the boot task */
 392                 } else if (result->status == LOAD_CANCELLED) {
 393                         pending = true;
 394                 }
 395         }
 396
 397         if (!pending)
 398                 talloc_free(task);
 399 }
 400
 401 static void boot_process(struct load_url_result *result, void *data)
 402 {
 403         struct boot_task *task = data;
 404         int rc = -1;
 405
 406         if (task->cancelled) {
 407                 cleanup_cancellations(task, result);
 408                 return;
 409         }
 410
 411         if (load_pending(task->image) ||
 412                         load_pending(task->initrd) ||
 413                         load_pending(task->dtb))
 414                 return;
 415
 416         if (check_load(task, "kernel image", task->image) ||
 417                         check_load(task, "initrd", task->initrd) ||
 418                         check_load(task, "dtb", task->dtb))
 419                 goto no_load;
 420
 421         if (task->verify_signature) {
 422                 if (load_pending(task->image_signature) ||
 423                                 load_pending(task->initrd_signature) ||
 424                                 load_pending(task->dtb_signature) ||
 425                                 load_pending(task->cmdline_signature))
 426                         return;
 427         }
 428         if (task->decrypt_files) {
 429                 if (load_pending(task->cmdline_signature))
 430                         return;
 431         }
 432
 433         if (task->verify_signature) {
 434                 if (check_load(task, "kernel image signature",
 435                                         task->image_signature) ||
 436                                 check_load(task, "initrd signature",
 437                                         task->initrd_signature) ||
 438                                 check_load(task, "dtb signature",
 439                                         task->dtb_signature) ||
 440                                 check_load(task, "command line signature",
 441                                         task->cmdline_signature))
 442                         goto no_sig_load;
 443         }
 444         if (task->decrypt_files) {
 445                 if (load_pending(task->cmdline_signature))
 446                         return;
 447
 448                 if (check_load(task, "command line signature",
 449                                         task->cmdline_signature))
 450                         goto no_decrypt_sig_load;
 451         }
 452
 453         /* we make a copy of the local paths, as the boot hooks might update
 454          * and/or create these */
 455         task->local_image = task->image ? task->image->local : NULL;
 456         task->local_initrd = task->initrd ? task->initrd->local : NULL;
 457         task->local_dtb = task->dtb ? task->dtb->local : NULL;
 458
 459         if (task->verify_signature) {
 460                 task->local_image_signature = task->image_signature ?
 461                         task->image_signature->local : NULL;
 462                 task->local_initrd_signature = task->initrd_signature ?
 463                         task->initrd_signature->local : NULL;
 464                 task->local_dtb_signature = task->dtb_signature ?
 465                         task->dtb_signature->local : NULL;
 466         }
 467         if (task->verify_signature || task->decrypt_files) {
 468                 task->local_cmdline_signature = task->cmdline_signature ?
 469                         task->cmdline_signature->local : NULL;
 470         }
 471
 472         run_boot_hooks(task);
 473
 474         update_status(task->status_fn, task->status_arg, STATUS_INFO,
 475                         _("Performing kexec load"));
 476
 477         rc = kexec_load(task);
 478         pb_log("%s: kexec_load returned %d\n", __func__, rc);
 479         if (rc == KEXEC_LOAD_DECRYPTION_FALURE) {
 480                 update_status(task->status_fn, task->status_arg,
 481                                 STATUS_ERROR, _("Decryption failed"));
 482         }
 483         else if (rc == KEXEC_LOAD_SIGNATURE_FAILURE) {
 484                 update_status(task->status_fn, task->status_arg,
 485                                 STATUS_ERROR,
 486                                 _("Signature verification failed"));
 487         }
 488         else if (rc == KEXEC_LOAD_SIG_SETUP_INVALID) {
 489                 update_status(task->status_fn, task->status_arg,
 490                                 STATUS_ERROR,
 491                                 _("Invalid signature configuration"));
 492         }
 493
 494 no_sig_load:
 495         cleanup_load(task->image_signature);
 496         cleanup_load(task->initrd_signature);
 497         cleanup_load(task->dtb_signature);
 498
 499 no_decrypt_sig_load:
 500         cleanup_load(task->cmdline_signature);
 501
 502 no_load:
 503         cleanup_load(task->image);
 504         cleanup_load(task->initrd);
 505         cleanup_load(task->dtb);
 506
 507         if (!rc) {
 508                 update_status(task->status_fn, task->status_arg,
 509                                 STATUS_INFO, _("Performing kexec reboot"));
 510
 511                 rc = kexec_reboot(task);
 512                 if (rc) {
 513                         update_status(task->status_fn, task->status_arg,
 514                                         STATUS_ERROR,
 515                                         _("kexec reboot failed"));
 516                 }
 517         }
 518 }
 519
 520 static int start_url_load(struct boot_task *task, const char *name,
 521                 struct pb_url *url, struct load_url_result **result)
 522 {
 523         if (!url)
 524                 return 0;
 525
 526         *result = load_url_async(task, url, boot_process, task, NULL,
 527                                  task->status_arg);
 528         if (!*result) {
 529                 update_status(task->status_fn, task->status_arg,
 530                                 STATUS_ERROR, _("Error loading %s"), name);
 531                 return -1;
 532         }
 533         return 0;
 534 }
 535
 536 struct boot_task *boot(void *ctx, struct discover_boot_option *opt,
 537                 struct boot_command *cmd, int dry_run,
 538                 boot_status_fn status_fn, void *status_arg)
 539 {
 540         struct pb_url *image = NULL, *initrd = NULL, *dtb = NULL;
 541         struct pb_url *image_sig = NULL, *initrd_sig = NULL, *dtb_sig = NULL,
 542                 *cmdline_sig = NULL;
 543         const struct config *config = config_get();
 544         struct boot_task *boot_task;
 545         const char *boot_desc;
 546         int rc;
 547         int lockdown_type;
 548
 549         if (opt && opt->option->name)
 550                 boot_desc = opt->option->name;
 551         else if (cmd && cmd->boot_image_file)
 552                 boot_desc = cmd->boot_image_file;
 553         else
 554                 boot_desc = _("(unknown)");
 555
 556         update_status(status_fn, status_arg, STATUS_INFO,
 557                         _("Booting %s"), boot_desc);
 558
 559         if (cmd && cmd->boot_image_file) {
 560                 image = pb_url_parse(opt, cmd->boot_image_file);
 561         } else if (opt && opt->boot_image) {
 562                 image = opt->boot_image->url;
 563         } else {
 564                 pb_log("%s: no image specified\n", __func__);
 565                 update_status(status_fn, status_arg, STATUS_INFO,
 566                                 _("Boot failed: no image specified"));
 567                 return NULL;
 568         }
 569
 570         if (cmd && cmd->initrd_file) {
 571                 initrd = pb_url_parse(opt, cmd->initrd_file);
 572         } else if (opt && opt->initrd) {
 573                 initrd = opt->initrd->url;
 574         }
 575
 576         if (cmd && cmd->dtb_file) {
 577                 dtb = pb_url_parse(opt, cmd->dtb_file);
 578         } else if (opt && opt->dtb) {
 579                 dtb = opt->dtb->url;
 580         }
 581
 582         boot_task = talloc_zero(ctx, struct boot_task);
 583         boot_task->dry_run = dry_run;
 584         boot_task->status_fn = status_fn;
 585         boot_task->status_arg = status_arg;
 586
 587         lockdown_type = lockdown_status();
 588         boot_task->verify_signature = (lockdown_type == PB_LOCKDOWN_SIGN);
 589         boot_task->decrypt_files = (lockdown_type == PB_LOCKDOWN_DECRYPT);
 590
 591         if (cmd && cmd->boot_args) {
 592                 boot_task->args = talloc_strdup(boot_task, cmd->boot_args);
 593         } else if (opt && opt->option->boot_args) {
 594                 boot_task->args = talloc_strdup(boot_task,
 595                                                 opt->option->boot_args);
 596         } else {
 597                 boot_task->args = NULL;
 598         }
 599
 600         if (cmd && cmd->console && !config->manual_console)
 601                 boot_task->boot_console = talloc_strdup(boot_task, cmd->console);
 602         else
 603                 boot_task->boot_console = config ? config->boot_console : NULL;
 604
 605         if (boot_task->verify_signature || boot_task->decrypt_files) {
 606                 if (cmd && cmd->args_sig_file) {
 607                         cmdline_sig = pb_url_parse(opt, cmd->args_sig_file);
 608                 } else if (opt && opt->args_sig_file) {
 609                         cmdline_sig = opt->args_sig_file->url;
 610                 } else {
 611                         pb_log("%s: no command line signature file"
 612                                 " specified\n", __func__);
 613                         update_status(status_fn, status_arg, STATUS_INFO,
 614                                         _("Boot failed: no command line"
 615                                                 " signature file specified"));
 616                         talloc_free(boot_task);
 617                         return NULL;
 618                 }
 619         }
 620
 621         /* start async loads for boot resources */
 622         rc = start_url_load(boot_task, _("kernel image"),
 623                         image, &boot_task->image)
 624           || start_url_load(boot_task, _("initrd"), initrd, &boot_task->initrd)
 625           || start_url_load(boot_task, _("dtb"), dtb, &boot_task->dtb);
 626
 627         if (boot_task->verify_signature) {
 628                 /* Generate names of associated signature files and load */
 629                 if (image) {
 630                         image_sig = gpg_get_signature_url(ctx, image);
 631                         rc |= start_url_load(boot_task,
 632                                 _("kernel image signature"), image_sig,
 633                                 &boot_task->image_signature);
 634                 }
 635                 if (initrd) {
 636                         initrd_sig = gpg_get_signature_url(ctx, initrd);
 637                         rc |= start_url_load(boot_task, _("initrd signature"),
 638                                 initrd_sig, &boot_task->initrd_signature);
 639                 }
 640                 if (dtb) {
 641                         dtb_sig = gpg_get_signature_url(ctx, dtb);
 642                         rc |= start_url_load(boot_task, _("dtb signature"),
 643                                 dtb_sig, &boot_task->dtb_signature);
 644                 }
 645         }
 646
 647         if (boot_task->verify_signature || boot_task->decrypt_files) {
 648                 rc |= start_url_load(boot_task,
 649                         _("kernel command line signature"), cmdline_sig,
 650                         &boot_task->cmdline_signature);
 651         }
 652
 653         /* If all URLs are local, we may be done. */
 654         if (rc) {
 655                 /* Don't call boot_cancel() to preserve the status update */
 656                 boot_task->cancelled = true;
 657                 cleanup_cancellations(boot_task, NULL);
 658                 return NULL;
 659         }
 660
 661         boot_process(NULL, boot_task);
 662
 663         return boot_task;
 664 }
 665
 666 void boot_cancel(struct boot_task *task)
 667 {
 668         task->cancelled = true;
 669
 670         update_status(task->status_fn, task->status_arg, STATUS_INFO,
 671                         _("Boot cancelled"));
 672
 673         cleanup_cancellations(task, NULL);
 674 }