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         if (result->status != LOAD_ERROR)
 313                 return 0;
 314
 315         update_status(task->status_fn, task->status_arg,
 316                         STATUS_ERROR,
 317                         _("Couldn't load %s"), name);
 318         return -1;
 319 }
 320
 321 static void cleanup_load(struct load_url_result *result)
 322 {
 323         if (!result)
 324                 return;
 325         if (result->status != LOAD_OK)
 326                 return;
 327         if (!result->cleanup_local)
 328                 return;
 329         unlink(result->local);
 330 }
 331
 332 static void cleanup_cancellations(struct boot_task *task,
 333                 struct load_url_result *cur_result)
 334 {
 335         struct load_url_result *result, **results[] = {
 336                 &task->image, &task->initrd, &task->dtb,
 337         };
 338         bool pending = false;
 339         unsigned int i;
 340
 341         for (i = 0; i < ARRAY_SIZE(results); i++) {
 342                 result = *results[i];
 343
 344                 if (!result)
 345                         continue;
 346
 347                 /* We need to cleanup and free any completed loads */
 348                 if (result == cur_result || result->status == LOAD_OK
 349                                 || result->status == LOAD_ERROR) {
 350                         cleanup_load(result);
 351                         talloc_free(result);
 352                         *results[i] = NULL;
 353
 354                 /* ... and cancel any pending loads, which we'll free in
 355                  * the completion callback */
 356                 } else if (result->status == LOAD_ASYNC) {
 357                         load_url_async_cancel(result);
 358                         pending = true;
 359
 360                 /* if we're waiting for a cancellation, we still need to
 361                  * wait for the completion before freeing the boot task */
 362                 } else if (result->status == LOAD_CANCELLED) {
 363                         pending = true;
 364                 }
 365         }
 366
 367         if (!pending)
 368                 talloc_free(task);
 369 }
 370
 371 static void boot_process(struct load_url_result *result, void *data)
 372 {
 373         struct boot_task *task = data;
 374         int rc = -1;
 375
 376         if (task->cancelled) {
 377                 cleanup_cancellations(task, result);
 378                 return;
 379         }
 380
 381         if (load_pending(task->image) ||
 382                         load_pending(task->initrd) ||
 383                         load_pending(task->dtb))
 384                 return;
 385
 386         if (check_load(task, "kernel image", task->image) ||
 387                         check_load(task, "initrd", task->initrd) ||
 388                         check_load(task, "dtb", task->dtb))
 389                 goto no_load;
 390
 391         if (task->verify_signature) {
 392                 if (load_pending(task->image_signature) ||
 393                                 load_pending(task->initrd_signature) ||
 394                                 load_pending(task->dtb_signature) ||
 395                                 load_pending(task->cmdline_signature))
 396                         return;
 397         }
 398         if (task->decrypt_files) {
 399                 if (load_pending(task->cmdline_signature))
 400                         return;
 401         }
 402
 403         if (task->verify_signature) {
 404                 if (check_load(task, "kernel image signature",
 405                                         task->image_signature) ||
 406                                 check_load(task, "initrd signature",
 407                                         task->initrd_signature) ||
 408                                 check_load(task, "dtb signature",
 409                                         task->dtb_signature) ||
 410                                 check_load(task, "command line signature",
 411                                         task->cmdline_signature))
 412                         goto no_sig_load;
 413         }
 414         if (task->decrypt_files) {
 415                 if (load_pending(task->cmdline_signature))
 416                         return;
 417
 418                 if (check_load(task, "command line signature",
 419                                         task->cmdline_signature))
 420                         goto no_decrypt_sig_load;
 421         }
 422
 423         /* we make a copy of the local paths, as the boot hooks might update
 424          * and/or create these */
 425         task->local_image = task->image ? task->image->local : NULL;
 426         task->local_initrd = task->initrd ? task->initrd->local : NULL;
 427         task->local_dtb = task->dtb ? task->dtb->local : NULL;
 428
 429         if (task->verify_signature) {
 430                 task->local_image_signature = task->image_signature ?
 431                         task->image_signature->local : NULL;
 432                 task->local_initrd_signature = task->initrd_signature ?
 433                         task->initrd_signature->local : NULL;
 434                 task->local_dtb_signature = task->dtb_signature ?
 435                         task->dtb_signature->local : NULL;
 436         }
 437         if (task->verify_signature || task->decrypt_files) {
 438                 task->local_cmdline_signature = task->cmdline_signature ?
 439                         task->cmdline_signature->local : NULL;
 440         }
 441
 442         run_boot_hooks(task);
 443
 444         update_status(task->status_fn, task->status_arg, STATUS_INFO,
 445                         _("performing kexec_load"));
 446
 447         rc = kexec_load(task);
 448         if (rc == KEXEC_LOAD_DECRYPTION_FALURE) {
 449                 update_status(task->status_fn, task->status_arg,
 450                                 STATUS_ERROR, _("decryption failed"));
 451         }
 452         else if (rc == KEXEC_LOAD_SIGNATURE_FAILURE) {
 453                 update_status(task->status_fn, task->status_arg,
 454                                 STATUS_ERROR,
 455                                 _("signature verification failed"));
 456         }
 457         else if (rc == KEXEC_LOAD_SIG_SETUP_INVALID) {
 458                 update_status(task->status_fn, task->status_arg,
 459                                 STATUS_ERROR,
 460                                 _("invalid signature configuration"));
 461         }
 462         else if (rc) {
 463                 update_status(task->status_fn, task->status_arg,
 464                                 STATUS_ERROR, _("kexec load failed"));
 465         }
 466
 467 no_sig_load:
 468         cleanup_load(task->image_signature);
 469         cleanup_load(task->initrd_signature);
 470         cleanup_load(task->dtb_signature);
 471
 472 no_decrypt_sig_load:
 473         cleanup_load(task->cmdline_signature);
 474
 475 no_load:
 476         cleanup_load(task->image);
 477         cleanup_load(task->initrd);
 478         cleanup_load(task->dtb);
 479
 480         if (!rc) {
 481                 update_status(task->status_fn, task->status_arg,
 482                                 STATUS_INFO, _("performing kexec reboot"));
 483
 484                 rc = kexec_reboot(task);
 485                 if (rc) {
 486                         update_status(task->status_fn, task->status_arg,
 487                                         STATUS_ERROR,
 488                                         _("kexec reboot failed"));
 489                 }
 490         }
 491 }
 492
 493 static int start_url_load(struct boot_task *task, const char *name,
 494                 struct pb_url *url, struct load_url_result **result)
 495 {
 496         if (!url)
 497                 return 0;
 498
 499         *result = load_url_async(task, url, boot_process, task);
 500         if (!*result) {
 501                 update_status(task->status_fn, task->status_arg,
 502                                 STATUS_ERROR, _("Error loading %s"), name);
 503                 return -1;
 504         }
 505         return 0;
 506 }
 507
 508 struct boot_task *boot(void *ctx, struct discover_boot_option *opt,
 509                 struct boot_command *cmd, int dry_run,
 510                 boot_status_fn status_fn, void *status_arg)
 511 {
 512         struct pb_url *image = NULL, *initrd = NULL, *dtb = NULL;
 513         struct pb_url *image_sig = NULL, *initrd_sig = NULL, *dtb_sig = NULL,
 514                 *cmdline_sig = NULL;
 515         const struct config *config = config_get();
 516         struct boot_task *boot_task;
 517         const char *boot_desc;
 518         int rc;
 519         int lockdown_type;
 520
 521         if (opt && opt->option->name)
 522                 boot_desc = opt->option->name;
 523         else if (cmd && cmd->boot_image_file)
 524                 boot_desc = cmd->boot_image_file;
 525         else
 526                 boot_desc = _("(unknown)");
 527
 528         update_status(status_fn, status_arg, STATUS_INFO,
 529                         _("Booting %s."), boot_desc);
 530
 531         if (cmd && cmd->boot_image_file) {
 532                 image = pb_url_parse(opt, cmd->boot_image_file);
 533         } else if (opt && opt->boot_image) {
 534                 image = opt->boot_image->url;
 535         } else {
 536                 pb_log("%s: no image specified\n", __func__);
 537                 update_status(status_fn, status_arg, STATUS_INFO,
 538                                 _("Boot failed: no image specified"));
 539                 return NULL;
 540         }
 541
 542         if (cmd && cmd->initrd_file) {
 543                 initrd = pb_url_parse(opt, cmd->initrd_file);
 544         } else if (opt && opt->initrd) {
 545                 initrd = opt->initrd->url;
 546         }
 547
 548         if (cmd && cmd->dtb_file) {
 549                 dtb = pb_url_parse(opt, cmd->dtb_file);
 550         } else if (opt && opt->dtb) {
 551                 dtb = opt->dtb->url;
 552         }
 553
 554         boot_task = talloc_zero(ctx, struct boot_task);
 555         boot_task->dry_run = dry_run;
 556         boot_task->status_fn = status_fn;
 557         boot_task->status_arg = status_arg;
 558
 559         lockdown_type = lockdown_status();
 560         boot_task->verify_signature = (lockdown_type == PB_LOCKDOWN_SIGN);
 561         boot_task->decrypt_files = (lockdown_type == PB_LOCKDOWN_DECRYPT);
 562
 563         if (cmd && cmd->boot_args) {
 564                 boot_task->args = talloc_strdup(boot_task, cmd->boot_args);
 565         } else if (opt && opt->option->boot_args) {
 566                 boot_task->args = talloc_strdup(boot_task,
 567                                                 opt->option->boot_args);
 568         } else {
 569                 boot_task->args = NULL;
 570         }
 571
 572         if (cmd && cmd->console && !config->manual_console)
 573                 boot_task->boot_console = talloc_strdup(boot_task, cmd->console);
 574         else
 575                 boot_task->boot_console = config ? config->boot_console : NULL;
 576
 577         if (boot_task->verify_signature || boot_task->decrypt_files) {
 578                 if (cmd && cmd->args_sig_file) {
 579                         cmdline_sig = pb_url_parse(opt, cmd->args_sig_file);
 580                 } else if (opt && opt->args_sig_file) {
 581                         cmdline_sig = opt->args_sig_file->url;
 582                 } else {
 583                         pb_log("%s: no command line signature file"
 584                                 " specified\n", __func__);
 585                         update_status(status_fn, status_arg, STATUS_INFO,
 586                                         _("Boot failed: no command line"
 587                                                 " signature file specified"));
 588                         talloc_free(boot_task);
 589                         return NULL;
 590                 }
 591         }
 592
 593         /* start async loads for boot resources */
 594         rc = start_url_load(boot_task, "kernel image", image, &boot_task->image)
 595           || start_url_load(boot_task, "initrd", initrd, &boot_task->initrd)
 596           || start_url_load(boot_task, "dtb", dtb, &boot_task->dtb);
 597
 598         if (boot_task->verify_signature) {
 599                 /* Generate names of associated signature files and load */
 600                 if (image) {
 601                         image_sig = gpg_get_signature_url(ctx, image);
 602                         rc |= start_url_load(boot_task,
 603                                 "kernel image signature", image_sig,
 604                                 &boot_task->image_signature);
 605                 }
 606                 if (initrd) {
 607                         initrd_sig = gpg_get_signature_url(ctx, initrd);
 608                         rc |= start_url_load(boot_task, "initrd signature",
 609                                 initrd_sig, &boot_task->initrd_signature);
 610                 }
 611                 if (dtb) {
 612                         dtb_sig = gpg_get_signature_url(ctx, dtb);
 613                         rc |= start_url_load(boot_task, "dtb signature",
 614                                 dtb_sig, &boot_task->dtb_signature);
 615                 }
 616         }
 617
 618         if (boot_task->verify_signature || boot_task->decrypt_files) {
 619                 rc |= start_url_load(boot_task,
 620                         "kernel command line signature", cmdline_sig,
 621                         &boot_task->cmdline_signature);
 622         }
 623
 624         /* If all URLs are local, we may be done. */
 625         if (rc) {
 626                 /* Don't call boot_cancel() to preserve the status update */
 627                 boot_task->cancelled = true;
 628                 cleanup_cancellations(boot_task, NULL);
 629                 return NULL;
 630         }
 631
 632         boot_process(NULL, boot_task);
 633
 634         return boot_task;
 635 }
 636
 637 void boot_cancel(struct boot_task *task)
 638 {
 639         task->cancelled = true;
 640
 641         update_status(task->status_fn, task->status_arg, STATUS_INFO,
 642                         _("Boot cancelled"));
 643
 644         cleanup_cancellations(task, NULL);
 645 }