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