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

   1
   2 #define _GNU_SOURCE
   3
   4 #include <stdbool.h>
   5 #include <stdlib.h>
   6 #include <assert.h>
   7 #include <dirent.h>
   8 #include <string.h>
   9 #include <fcntl.h>
  10 #include <sys/types.h>
  11
  12 #include <log/log.h>
  13 #include <pb-protocol/pb-protocol.h>
  14 #include <process/process.h>
  15 #include <system/system.h>
  16 #include <talloc/talloc.h>
  17 #include <url/url.h>
  18
  19 #include "device-handler.h"
  20 #include "boot.h"
  21 #include "paths.h"
  22 #include "resource.h"
  23
  24 static const char *boot_hook_dir = PKG_SYSCONF_DIR "/boot.d";
  25 enum {
  26         BOOT_HOOK_EXIT_OK       = 0,
  27         BOOT_HOOK_EXIT_UPDATE   = 2,
  28 };
  29
  30 enum boot_process_state {
  31         BOOT_STATE_INITIAL,
  32         BOOT_STATE_IMAGE_LOADING,
  33         BOOT_STATE_INITRD_LOADING,
  34         BOOT_STATE_FINISH,
  35         BOOT_STATE_UNKNOWN,
  36 };
  37
  38
  39 struct boot_task {
  40         char *local_image;
  41         char *local_initrd;
  42         char *local_dtb;
  43         char *args;
  44         struct pb_url *image, *initrd, *dtb;
  45         boot_status_fn status_fn;
  46         void *status_arg;
  47         enum boot_process_state state;
  48         bool dry_run;
  49 };
  50
  51 /**
  52  * kexec_load - kexec load helper.
  53  */
  54 static int kexec_load(struct boot_task *boot_task)
  55 {
  56         int result;
  57         const char *argv[7];
  58         const char **p;
  59         char *s_initrd = NULL;
  60         char *s_dtb = NULL;
  61         char *s_args = NULL;
  62
  63         p = argv;
  64         *p++ = pb_system_apps.kexec;    /* 1 */
  65         *p++ = "-l";                    /* 2 */
  66
  67         if (boot_task->local_initrd) {
  68                 s_initrd = talloc_asprintf(boot_task, "--initrd=%s",
  69                                 boot_task->local_initrd);
  70                 assert(s_initrd);
  71                 *p++ = s_initrd;         /* 3 */
  72         }
  73
  74         if (boot_task->local_dtb) {
  75                 s_dtb = talloc_asprintf(boot_task, "--dtb=%s",
  76                                                 boot_task->local_dtb);
  77                 assert(s_dtb);
  78                 *p++ = s_dtb;            /* 4 */
  79         }
  80
  81         if (boot_task->args) {
  82                 s_args = talloc_asprintf(boot_task, "--append=%s",
  83                                                 boot_task->args);
  84                 assert(s_args);
  85                 *p++ = s_args;          /* 5 */
  86         }
  87
  88         *p++ = boot_task->local_image;  /* 6 */
  89         *p++ = NULL;                    /* 7 */
  90
  91         result = process_run_simple_argv(boot_task, argv);
  92
  93         if (result)
  94                 pb_log("%s: failed: (%d)\n", __func__, result);
  95
  96         return result;
  97 }
  98
  99 /**
 100  * kexec_reboot - Helper to boot the new kernel.
 101  *
 102  * Must only be called after a successful call to kexec_load().
 103  */
 104
 105 static int kexec_reboot(struct boot_task *task)
 106 {
 107         int result;
 108
 109         /* First try running shutdown.  Init scripts should run 'exec -e' */
 110         result = process_run_simple(task, pb_system_apps.shutdown, "-r",
 111                         "now", NULL);
 112
 113         /* On error, force a kexec with the -e option */
 114         if (result) {
 115                 result = process_run_simple(task, pb_system_apps.kexec,
 116                                                 "-e", NULL);
 117         }
 118
 119         if (result)
 120                 pb_log("%s: failed: (%d)\n", __func__, result);
 121
 122         /* okay, kexec -e -f */
 123         if (result) {
 124                 result = process_run_simple(task, pb_system_apps.kexec,
 125                                                 "-e", "-f", NULL);
 126         }
 127
 128         if (result)
 129                 pb_log("%s: failed: (%d)\n", __func__, result);
 130
 131
 132         return result;
 133 }
 134
 135 static void __attribute__((format(__printf__, 4, 5))) update_status(
 136                 boot_status_fn fn, void *arg, int type, char *fmt, ...)
 137 {
 138         struct boot_status status;
 139         va_list ap;
 140
 141         va_start(ap, fmt);
 142         status.message = talloc_vasprintf(NULL, fmt, ap);
 143         va_end(ap);
 144
 145         status.type = type;
 146         status.progress = -1;
 147         status.detail = NULL;
 148
 149         fn(arg, &status);
 150
 151         talloc_free(status.message);
 152 }
 153
 154 static void boot_hook_update_param(void *ctx, struct boot_task *task,
 155                 const char *name, const char *value)
 156 {
 157         struct p {
 158                 const char *name;
 159                 char **p;
 160         } *param, params[] = {
 161                 { "boot_image",         &task->local_image },
 162                 { "boot_initrd",        &task->local_initrd },
 163                 { "boot_dtb",           &task->local_dtb },
 164                 { "boot_args",          &task->args },
 165                 { NULL, NULL },
 166         };
 167
 168         for (param = params; param->name; param++) {
 169                 if (strcmp(param->name, name))
 170                         continue;
 171
 172                 *param->p = talloc_strdup(ctx, value);
 173                 return;
 174         }
 175 }
 176
 177 static void boot_hook_update(struct boot_task *task, const char *hookname,
 178                 char *buf)
 179 {
 180         char *line, *name, *val, *sep;
 181         char *saveptr;
 182
 183         for (;; buf = NULL) {
 184
 185                 line = strtok_r(buf, "\n", &saveptr);
 186                 if (!line)
 187                         break;
 188
 189                 sep = strchr(line, '=');
 190                 if (!sep)
 191                         continue;
 192
 193                 *sep = '\0';
 194                 name = line;
 195                 val = sep + 1;
 196
 197                 boot_hook_update_param(task, task, name, val);
 198
 199                 pb_log("boot hook %s specified %s=%s\n",
 200                                 hookname, name, val);
 201         }
 202 }
 203
 204 static void boot_hook_setenv(struct boot_task *task)
 205 {
 206         unsetenv("boot_image");
 207         unsetenv("boot_initrd");
 208         unsetenv("boot_dtb");
 209         unsetenv("boot_args");
 210
 211         setenv("boot_image", task->local_image, 1);
 212         if (task->local_initrd)
 213                 setenv("boot_initrd", task->local_initrd, 1);
 214         if (task->local_dtb)
 215                 setenv("boot_dtb", task->local_dtb, 1);
 216         if (task->args)
 217                 setenv("boot_args", task->args, 1);
 218 }
 219
 220 static int hook_filter(const struct dirent *dirent)
 221 {
 222         return dirent->d_type == DT_REG || dirent->d_type == DT_LNK;
 223 }
 224
 225 static int hook_cmp(const struct dirent **a, const struct dirent **b)
 226 {
 227         return strcmp((*a)->d_name, (*b)->d_name);
 228 }
 229
 230 static void run_boot_hooks(struct boot_task *task)
 231 {
 232         struct dirent **hooks;
 233         int i, n;
 234
 235         n = scandir(boot_hook_dir, &hooks, hook_filter, hook_cmp);
 236         if (n < 1)
 237                 return;
 238
 239         update_status(task->status_fn, task->status_arg, BOOT_STATUS_INFO,
 240                         "running boot hooks");
 241
 242         boot_hook_setenv(task);
 243
 244         for (i = 0; i < n; i++) {
 245                 const char *argv[2] = { NULL, NULL };
 246                 struct process *process;
 247                 char *path;
 248                 int rc;
 249
 250                 path = join_paths(task, boot_hook_dir, hooks[i]->d_name);
 251
 252                 if (access(path, X_OK)) {
 253                         talloc_free(path);
 254                         continue;
 255                 }
 256
 257                 process = process_create(task);
 258
 259                 argv[0] = path;
 260                 process->path = path;
 261                 process->argv = argv;
 262                 process->keep_stdout = true;
 263
 264                 pb_log("running boot hook %s\n", hooks[i]->d_name);
 265
 266                 rc = process_run_sync(process);
 267                 if (rc) {
 268                         pb_log("boot hook exec failed!\n");
 269
 270                 } else if (WIFEXITED(process->exit_status) &&
 271                            WEXITSTATUS(process->exit_status)
 272                                 == BOOT_HOOK_EXIT_UPDATE) {
 273                         /* if the hook returned with BOOT_HOOK_EXIT_UPDATE,
 274                          * then we process stdout to look for updated params
 275                          */
 276                         if (rc == BOOT_HOOK_EXIT_UPDATE) {
 277                                 boot_hook_update(task, hooks[i]->d_name,
 278                                                 process->stdout_buf);
 279                                 boot_hook_setenv(task);
 280                         }
 281                 }
 282
 283                 process_release(process);
 284                 talloc_free(path);
 285         }
 286
 287         free(hooks);
 288 }
 289
 290 static void boot_process(void *ctx, int status __attribute__((unused)))
 291 {
 292         struct boot_task *task = ctx;
 293         unsigned int clean_image = 0;
 294         unsigned int clean_initrd = 0;
 295         unsigned int clean_dtb = 0;
 296         int result = -1;
 297
 298         if (task->state == BOOT_STATE_INITIAL) {
 299                 update_status(task->status_fn, task->status_arg,
 300                                 BOOT_STATUS_INFO, "loading kernel");
 301                 task->local_image = load_url_async(task, task->image,
 302                                         &clean_image, boot_process);
 303                 if (!task->local_image) {
 304                         update_status(task->status_fn, task->status_arg,
 305                                         BOOT_STATUS_ERROR,
 306                                         "Couldn't load kernel image");
 307                         goto no_load;
 308                 } else {
 309                         task->state = BOOT_STATE_IMAGE_LOADING;
 310                         return;
 311                 }
 312         }
 313
 314         if (task->state == BOOT_STATE_IMAGE_LOADING) {
 315                 if (task->initrd) {
 316                         update_status(task->status_fn, task->status_arg,
 317                                         BOOT_STATUS_INFO, "loading initrd");
 318                         task->local_initrd = load_url_async(task, task->initrd,
 319                                         &clean_initrd, boot_process);
 320                         if (!task->local_initrd) {
 321                                 update_status(task->status_fn, task->status_arg,
 322                                                 BOOT_STATUS_ERROR,
 323                                                 "Couldn't load initrd image");
 324                                 goto no_load;
 325                         } else {
 326                                 task->state = BOOT_STATE_INITRD_LOADING;
 327                                 return;
 328                         }
 329                 } else {
 330                         task->state = BOOT_STATE_INITRD_LOADING;
 331                 }
 332         }
 333
 334         if (task->state == BOOT_STATE_INITRD_LOADING) {
 335                 if (task->dtb) {
 336                         update_status(task->status_fn, task->status_arg,
 337                                         BOOT_STATUS_INFO,
 338                                         "loading device tree");
 339                         task->local_dtb = load_url_async(task, task->dtb,
 340                                                 &clean_dtb, boot_process);
 341                         if (!task->local_dtb) {
 342                                 update_status(task->status_fn, task->status_arg,
 343                                                 BOOT_STATUS_ERROR,
 344                                                 "Couldn't load device tree");
 345                                 goto no_load;
 346                         } else {
 347                                 task->state = BOOT_STATE_FINISH;
 348                                 return;
 349                         }
 350                 } else {
 351                         task->state = BOOT_STATE_FINISH;
 352                 }
 353         }
 354
 355         if (task->state != BOOT_STATE_FINISH) {
 356                 task->state = BOOT_STATE_UNKNOWN;
 357                 return;
 358         }
 359
 360         run_boot_hooks(task);
 361
 362         update_status(task->status_fn, task->status_arg, BOOT_STATUS_INFO,
 363                         "performing kexec_load");
 364
 365         result = kexec_load(task);
 366
 367         if (result) {
 368                 update_status(task->status_fn, task->status_arg,
 369                                 BOOT_STATUS_ERROR, "kexec load failed");
 370         }
 371
 372 no_load:
 373         if (clean_image)
 374                 unlink(task->local_image);
 375         if (clean_initrd)
 376                 unlink(task->local_initrd);
 377         if (clean_dtb)
 378                 unlink(task->local_dtb);
 379
 380         if (!result) {
 381                 update_status(task->status_fn, task->status_arg,
 382                                 BOOT_STATUS_INFO,
 383                                 "performing kexec reboot");
 384
 385                 result = kexec_reboot(task);
 386
 387                 if (result) {
 388                         update_status(task->status_fn, task->status_arg,
 389                                         BOOT_STATUS_ERROR,
 390                                         "kexec reboot failed");
 391                 }
 392         }
 393
 394         talloc_free(task);
 395 }
 396
 397 int boot(void *ctx, struct discover_boot_option *opt, struct boot_command *cmd,
 398                 int dry_run, boot_status_fn status_fn, void *status_arg)
 399 {
 400         struct boot_task *boot_task;
 401         struct pb_url *image = NULL;
 402         const char *boot_desc;
 403
 404         if (opt && opt->option->name)
 405                 boot_desc = opt->option->name;
 406         else if (cmd && cmd->boot_image_file)
 407                 boot_desc = cmd->boot_image_file;
 408         else
 409                 boot_desc = "(unknown)";
 410
 411         update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 412                         "Booting %s.", boot_desc);
 413
 414         if (cmd && cmd->boot_image_file) {
 415                 image = pb_url_parse(opt, cmd->boot_image_file);
 416         } else if (opt && opt->boot_image) {
 417                 image = opt->boot_image->url;
 418         } else {
 419                 pb_log("%s: no image specified\n", __func__);
 420                 update_status(status_fn, status_arg, BOOT_STATUS_INFO,
 421                                 "Boot failed: no image specified");
 422                 return -1;
 423         }
 424
 425         boot_task = talloc_zero(ctx, struct boot_task);
 426         boot_task->image = image;
 427         boot_task->dry_run = dry_run;
 428         boot_task->status_fn = status_fn;
 429         boot_task->status_arg = status_arg;
 430         boot_task->state = BOOT_STATE_INITIAL;
 431
 432         if (cmd && cmd->initrd_file) {
 433                 boot_task->initrd = pb_url_parse(opt, cmd->initrd_file);
 434         } else if (opt && opt->initrd) {
 435                 boot_task->initrd = opt->initrd->url;
 436         }
 437
 438         if (cmd && cmd->dtb_file) {
 439                 boot_task->dtb = pb_url_parse(opt, cmd->dtb_file);
 440         } else if (opt && opt->dtb) {
 441                 boot_task->dtb = opt->dtb->url;
 442         }
 443
 444         if (cmd && cmd->boot_args) {
 445                 boot_task->args = talloc_strdup(boot_task, cmd->boot_args);
 446         } else if (opt && opt->option->boot_args) {
 447                 boot_task->args = talloc_strdup(boot_task,
 448                                                 opt->option->boot_args);
 449         } else {
 450                 boot_task->args = NULL;
 451         }
 452
 453         boot_process(boot_task, 0);
 454
 455         return 0;
 456 }