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