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 boot_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         status.progress = -1;
 158         status.detail = NULL;
 159
 160         pb_debug("boot status: [%d] %s\n", type, status.message);
 161
 162         fn(arg, &status);
 163
 164         talloc_free(status.message);
 165 }
 166
 167 static void boot_hook_update_param(void *ctx, struct boot_task *task,
 168                 const char *name, const char *value)
 169 {
 170         struct p {
 171                 const char *name;
 172                 const char **p;
 173         } *param, params[] = {
 174                 { "boot_image",         &task->local_image },
 175                 { "boot_initrd",        &task->local_initrd },
 176                 { "boot_dtb",           &task->local_dtb },
 177                 { "boot_args",          &task->args },
 178                 { NULL, NULL },
 179         };
 180
 181         for (param = params; param->name; param++) {
 182                 if (strcmp(param->name, name))
 183                         continue;
 184
 185                 *param->p = talloc_strdup(ctx, value);
 186                 return;
 187         }
 188 }
 189
 190 static void boot_hook_update(struct boot_task *task, const char *hookname,
 191                 char *buf)
 192 {
 193         char *line, *name, *val, *sep;
 194         char *saveptr = NULL;
 195
 196         for (;; buf = NULL) {
 197
 198                 line = strtok_r(buf, "\n", &saveptr);
 199                 if (!line)
 200                         break;
 201
 202                 sep = strchr(line, '=');
 203                 if (!sep)
 204                         continue;
 205
 206                 *sep = '\0';
 207                 name = line;
 208                 val = sep + 1;
 209
 210                 boot_hook_update_param(task, task, name, val);
 211
 212                 pb_log("boot hook %s specified %s=%s\n",
 213                                 hookname, name, val);
 214         }
 215 }
 216
 217 static void boot_hook_setenv(struct boot_task *task)
 218 {
 219         unsetenv("boot_image");
 220         unsetenv("boot_initrd");
 221         unsetenv("boot_dtb");
 222         unsetenv("boot_args");
 223         unsetenv("boot_console");
 224
 225         setenv("boot_image", task->local_image, 1);
 226         if (task->local_initrd)
 227                 setenv("boot_initrd", task->local_initrd, 1);
 228         if (task->local_dtb)
 229                 setenv("boot_dtb", task->local_dtb, 1);
 230         if (task->args)
 231                 setenv("boot_args", task->args, 1);
 232         if (task->boot_console)
 233                 setenv("boot_console", task->boot_console, 1);
 234 }
 235
 236 static int hook_filter(const struct dirent *dirent)
 237 {
 238         return dirent->d_type == DT_REG || dirent->d_type == DT_LNK;
 239 }
 240
 241 static int hook_cmp(const struct dirent **a, const struct dirent **b)
 242 {
 243         return strcmp((*a)->d_name, (*b)->d_name);
 244 }
 245
 246 static void run_boot_hooks(struct boot_task *task)
 247 {
 248         struct dirent **hooks;
 249         int i, n;
 250
 251         n = scandir(boot_hook_dir, &hooks, hook_filter, hook_cmp);
 252         if (n < 1)
 253                 return;
 254
 255         update_status(task->status_fn, task->status_arg, BOOT_STATUS_INFO,
 256                         _("running boot hooks"));
 257
 258         boot_hook_setenv(task);
 259
 260         for (i = 0; i < n; i++) {
 261                 const char *argv[2] = { NULL, NULL };
 262                 struct process *process;
 263                 char *path;
 264                 int rc;
 265
 266                 path = join_paths(task, boot_hook_dir, hooks[i]->d_name);
 267
 268                 if (access(path, X_OK)) {
 269                         talloc_free(path);
 270                         continue;
 271                 }
 272
 273                 process = process_create(task);
 274
 275                 argv[0] = path;
 276                 process->path = path;
 277                 process->argv = argv;
 278                 process->keep_stdout = true;
 279
 280                 pb_log("running boot hook %s\n", hooks[i]->d_name);
 281
 282                 rc = process_run_sync(process);
 283                 if (rc) {
 284                         pb_log("boot hook exec failed!\n");
 285
 286                 } else if (WIFEXITED(process->exit_status) &&
 287                            WEXITSTATUS(process->exit_status)
 288                                 == BOOT_HOOK_EXIT_UPDATE) {
 289                         /* if the hook returned with BOOT_HOOK_EXIT_UPDATE,
 290                          * then we process stdout to look for updated params
 291                          */
 292                         boot_hook_update(task, hooks[i]->d_name,
 293                                         process->stdout_buf);
 294                         boot_hook_setenv(task);
 295                 }
 296
 297                 process_release(process);
 298                 talloc_free(path);
 299         }
 300
 301         free(hooks);
 302 }
 303
 304 static bool load_pending(struct load_url_result *result)
 305 {
 306         return result && result->status == LOAD_ASYNC;
 307 }
 308
 309 static int check_load(struct boot_task *task, const char *name,
 310                 struct load_url_result *result)
 311 {
 312         if (!result)
 313                 return 0;
 314         if (result->status != LOAD_ERROR)
 315                 return 0;
 316
 317         update_status(task->status_fn, task->status_arg,
 318                         BOOT_STATUS_ERROR,
 319                         _("Couldn't load %s"), name);
 320         return -1;
 321 }
 322
 323 static void cleanup_load(struct load_url_result *result)
 324 {
 325         if (!result)
 326                 return;
 327         if (result->status != LOAD_OK)
 328                 return;
 329         if (!result->cleanup_local)
 330                 return;
 331         unlink(result->local);
 332 }
 333
 334 static void cleanup_cancellations(struct boot_task *task,
 335                 struct load_url_result *cur_result)
 336 {
 337         struct load_url_result *result, **results[] = {
 338                 &task->image, &task->initrd, &task->dtb,
 339         };
 340         bool pending = false;
 341         unsigned int i;
 342
 343         for (i = 0; i < ARRAY_SIZE(results); i++) {
 344                 result = *results[i];
 345
 346                 if (!result)
 347                         continue;
 348
 349                 /* We need to cleanup and free any completed loads */
 350                 if (result == cur_result || result->status == LOAD_OK
 351                                 || result->status == LOAD_ERROR) {
 352                         cleanup_load(result);
 353                         talloc_free(result);
 354                         *results[i] = NULL;
 355
 356                 /* ... and cancel any pending loads, which we'll free in
 357                  * the completion callback */
 358                 } else if (result->status == LOAD_ASYNC) {
 359                         load_url_async_cancel(result);
 360                         pending = true;
 361
 362                 /* if we're waiting for a cancellation, we still need to
 363                  * wait for the completion before freeing the boot task */
 364                 } else if (result->status == LOAD_CANCELLED) {
 365                         pending = true;
 366                 }
 367         }
 368
 369         if (!pending)
 370                 talloc_free(task);
 371 }
 372
 373 static void boot_process(struct load_url_result *result, void *data)
 374 {
 375         struct boot_task *task = data;
 376         int rc = -1;
 377
 378         if (task->cancelled) {
 379                 cleanup_cancellations(task, result);
 380                 return;
 381         }
 382
 383         if (load_pending(task->image) ||
 384                         load_pending(task->initrd) ||
 385                         load_pending(task->dtb))
 386                 return;
 387
 388         if (check_load(task, "kernel image", task->image) ||
 389                         check_load(task, "initrd", task->initrd) ||
 390                         check_load(task, "dtb", task->dtb))
 391                 goto no_load;
 392
 393         if (task->verify_signature) {
 394                 if (load_pending(task->image_signature) ||
 395                                 load_pending(task->initrd_signature) ||
 396                                 load_pending(task->dtb_signature) ||
 397                                 load_pending(task->cmdline_signature))
 398                         return;
 399         }
 400         if (task->decrypt_files) {
 401                 if (load_pending(task->cmdline_signature))
 402                         return;
 403         }
 404
 405         if (task->verify_signature) {
 406                 if (check_load(task, "kernel image signature",
 407                                         task->image_signature) ||
 408                                 check_load(task, "initrd signature",
 409                                         task->initrd_signature) ||
 410                                 check_load(task, "dtb signature",
 411                                         task->dtb_signature) ||
 412                                 check_load(task, "command line signature",
 413                                         task->cmdline_signature))
 414                         goto no_sig_load;
 415         }
 416         if (task->decrypt_files) {
 417                 if (load_pending(task->cmdline_signature))
 418                         return;
 419
 420                 if (check_load(task, "command line signature",
 421                                         task->cmdline_signature))
 422                         goto no_decrypt_sig_load;
 423         }
 424
 425         /* we make a copy of the local paths, as the boot hooks might update
 426          * and/or create these */
 427         task->local_image = task->image ? task->image->local : NULL;
 428         task->local_initrd = task->initrd ? task->initrd->local : NULL;
 429         task->local_dtb = task->dtb ? task->dtb->local : NULL;
 430
 431         if (task->verify_signature) {
 432                 task->local_image_signature = task->image_signature ?
 433                         task->image_signature->local : NULL;
 434                 task->local_initrd_signature = task->initrd_signature ?
 435                         task->initrd_signature->local : NULL;
 436                 task->local_dtb_signature = task->dtb_signature ?
 437                         task->dtb_signature->local : NULL;
 438         }
 439         if (task->verify_signature || task->decrypt_files) {
 440                 task->local_cmdline_signature = task->cmdline_signature ?
 441                         task->cmdline_signature->local : NULL;
 442         }
 443
 444         run_boot_hooks(task);
 445
 446         update_status(task->status_fn, task->status_arg, BOOT_STATUS_INFO,
 447                         _("performing kexec_load"));
 448
 449         rc = kexec_load(task);
 450         if (rc == KEXEC_LOAD_DECRYPTION_FALURE) {
 451                 update_status(task->status_fn, task->status_arg,
 452                                 BOOT_STATUS_ERROR, _("decryption failed"));
 453         }
 454         else if (rc == KEXEC_LOAD_SIGNATURE_FAILURE) {
 455                 update_status(task->status_fn, task->status_arg,
 456                                 BOOT_STATUS_ERROR,
 457                                 _("signature verification failed"));
 458         }
 459         else if (rc == KEXEC_LOAD_SIG_SETUP_INVALID) {
 460                 update_status(task->status_fn, task->status_arg,
 461                                 BOOT_STATUS_ERROR,
 462                                 _("invalid signature configuration"));
 463         }
 464         else if (rc) {
 465                 update_status(task->status_fn, task->status_arg,
 466                                 BOOT_STATUS_ERROR,
 467                                 _("kexec load failed"));
 468         }
 469
 470 no_sig_load:
 471         cleanup_load(task->image_signature);
 472         cleanup_load(task->initrd_signature);
 473         cleanup_load(task->dtb_signature);
 474
 475 no_decrypt_sig_load:
 476         cleanup_load(task->cmdline_signature);
 477
 478 no_load:
 479         cleanup_load(task->image);
 480         cleanup_load(task->initrd);
 481         cleanup_load(task->dtb);
 482
 483         if (!rc) {
 484                 update_status(task->status_fn, task->status_arg,
 485                                 BOOT_STATUS_INFO,
 486                                 _("performing kexec reboot"));
 487
 488                 rc = kexec_reboot(task);
 489                 if (rc) {
 490                         update_status(task->status_fn, task->status_arg,
 491                                         BOOT_STATUS_ERROR,
 492                                         _("kexec reboot failed"));
 493                 }
 494         }
 495 }
 496
 497 static int start_url_load(struct boot_task *task, const char *name,
 498                 struct pb_url *url, struct load_url_result **result)
 499 {
 500         if (!url)
 501                 return 0;
 502
 503         *result = load_url_async(task, url, boot_process, task);
 504         if (!*result) {
 505                 update_status(task->status_fn, task->status_arg,
 506                                 BOOT_STATUS_ERROR,
 507                                 _("Error loading %s"), name);
 508                 return -1;
 509         }
 510         return 0;
 511 }
 512
 513 struct boot_task *boot(void *ctx, struct discover_boot_option *opt,
 514                 struct boot_command *cmd, int dry_run,
 515                 boot_status_fn status_fn, void *status_arg)
 516 {
 517         struct pb_url *image = NULL, *initrd = NULL, *dtb = NULL;
 518         struct pb_url *image_sig = NULL, *initrd_sig = NULL, *dtb_sig = NULL,
 519                 *cmdline_sig = NULL;
 520         const struct config *config = config_get();
 521         struct boot_task *boot_task;
 522         const char *boot_desc;
 523         int rc;
 524         int lockdown_type;
 525
 526         if (opt && opt->option->name)
 527                 boot_desc = opt->option->name;
 528         else if (cmd && cmd->boot_image_file)
 529                 boot_desc = cmd->boot_image_file;
 530         else
 531                 boot_desc = _("(unknown)");
 532
 533         update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 534                         _("Booting %s."), boot_desc);
 535
 536         if (cmd && cmd->boot_image_file) {
 537                 image = pb_url_parse(opt, cmd->boot_image_file);
 538         } else if (opt && opt->boot_image) {
 539                 image = opt->boot_image->url;
 540         } else {
 541                 pb_log("%s: no image specified\n", __func__);
 542                 update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 543                                 _("Boot failed: no image specified"));
 544                 return NULL;
 545         }
 546
 547         if (cmd && cmd->initrd_file) {
 548                 initrd = pb_url_parse(opt, cmd->initrd_file);
 549         } else if (opt && opt->initrd) {
 550                 initrd = opt->initrd->url;
 551         }
 552
 553         if (cmd && cmd->dtb_file) {
 554                 dtb = pb_url_parse(opt, cmd->dtb_file);
 555         } else if (opt && opt->dtb) {
 556                 dtb = opt->dtb->url;
 557         }
 558
 559         boot_task = talloc_zero(ctx, struct boot_task);
 560         boot_task->dry_run = dry_run;
 561         boot_task->status_fn = status_fn;
 562         boot_task->status_arg = status_arg;
 563
 564         lockdown_type = lockdown_status();
 565         boot_task->verify_signature = (lockdown_type == PB_LOCKDOWN_SIGN);
 566         boot_task->decrypt_files = (lockdown_type == PB_LOCKDOWN_DECRYPT);
 567
 568         if (cmd && cmd->boot_args) {
 569                 boot_task->args = talloc_strdup(boot_task, cmd->boot_args);
 570         } else if (opt && opt->option->boot_args) {
 571                 boot_task->args = talloc_strdup(boot_task,
 572                                                 opt->option->boot_args);
 573         } else {
 574                 boot_task->args = NULL;
 575         }
 576
 577         if (cmd && cmd->console && !config->manual_console)
 578                 boot_task->boot_console = talloc_strdup(boot_task, cmd->console);
 579         else
 580                 boot_task->boot_console = config ? config->boot_console : NULL;
 581
 582         if (boot_task->verify_signature || boot_task->decrypt_files) {
 583                 if (cmd && cmd->args_sig_file) {
 584                         cmdline_sig = pb_url_parse(opt, cmd->args_sig_file);
 585                 } else if (opt && opt->args_sig_file) {
 586                         cmdline_sig = opt->args_sig_file->url;
 587                 } else {
 588                         pb_log("%s: no command line signature file"
 589                                 " specified\n", __func__);
 590                         update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 591                                         _("Boot failed: no command line"
 592                                                 " signature file specified"));
 593                         talloc_free(boot_task);
 594                         return NULL;
 595                 }
 596         }
 597
 598         /* start async loads for boot resources */
 599         rc = start_url_load(boot_task, "kernel image", image, &boot_task->image)
 600           || start_url_load(boot_task, "initrd", initrd, &boot_task->initrd)
 601           || start_url_load(boot_task, "dtb", dtb, &boot_task->dtb);
 602
 603         if (boot_task->verify_signature) {
 604                 /* Generate names of associated signature files and load */
 605                 if (image) {
 606                         image_sig = gpg_get_signature_url(ctx, image);
 607                         rc |= start_url_load(boot_task,
 608                                 "kernel image signature", image_sig,
 609                                 &boot_task->image_signature);
 610                 }
 611                 if (initrd) {
 612                         initrd_sig = gpg_get_signature_url(ctx, initrd);
 613                         rc |= start_url_load(boot_task, "initrd signature",
 614                                 initrd_sig, &boot_task->initrd_signature);
 615                 }
 616                 if (dtb) {
 617                         dtb_sig = gpg_get_signature_url(ctx, dtb);
 618                         rc |= start_url_load(boot_task, "dtb signature",
 619                                 dtb_sig, &boot_task->dtb_signature);
 620                 }
 621         }
 622
 623         if (boot_task->verify_signature || boot_task->decrypt_files) {
 624                 rc |= start_url_load(boot_task,
 625                         "kernel command line signature", cmdline_sig,
 626                         &boot_task->cmdline_signature);
 627         }
 628
 629         /* If all URLs are local, we may be done. */
 630         if (rc) {
 631                 /* Don't call boot_cancel() to preserve the status update */
 632                 boot_task->cancelled = true;
 633                 cleanup_cancellations(boot_task, NULL);
 634                 return NULL;
 635         }
 636
 637         boot_process(NULL, boot_task);
 638
 639         return boot_task;
 640 }
 641
 642 void boot_cancel(struct boot_task *task)
 643 {
 644         task->cancelled = true;
 645
 646         update_status(task->status_fn, task->status_arg, BOOT_STATUS_INFO,
 647                         _("Boot cancelled"));
 648
 649         cleanup_cancellations(task, NULL);
 650 }