discover: fix segfault on failed boot image load
[petitboot] / discover / boot.c
index ddb9e7dc367539343e09cb28d321388c5fecb452..e57810d54d46a10687c0182d9004d63b0349d188 100644 (file)
 
+#define _GNU_SOURCE
+
+#include <stdbool.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <dirent.h>
+#include <string.h>
+#include <fcntl.h>
+#include <sys/types.h>
+
+#include <log/log.h>
+#include <pb-protocol/pb-protocol.h>
+#include <system/system.h>
+#include <talloc/talloc.h>
+#include <url/url.h>
+
+#include "device-handler.h"
 #include "boot.h"
+#include "paths.h"
+#include "resource.h"
+
+static const char *boot_hook_dir = PKG_SYSCONF_DIR "/boot.d";
+enum {
+       BOOT_HOOK_EXIT_OK       = 0,
+       BOOT_HOOK_EXIT_UPDATE   = 2,
+};
+
+
+struct boot_task {
+       char *local_image;
+       char *local_initrd;
+       char *local_dtb;
+       char *args;
+
+       bool dry_run;
+};
 
-int boot(void *ctx, struct boot_option *opt, struct boot_command *cmd,
-               int dry_run)
+/**
+ * kexec_load - kexec load helper.
+ */
+static int kexec_load(struct boot_task *boot_task)
 {
-       /* todo: run kexec with options from opt & cmd */
-       (void)ctx;
-       (void)opt;
-       (void)cmd;
-       (void)dry_run;
+       int result;
+       const char *argv[7];
+       const char **p;
+       char *s_initrd = NULL;
+       char *s_dtb = NULL;
+       char *s_args = NULL;
+
+       p = argv;
+       *p++ = pb_system_apps.kexec;    /* 1 */
+       *p++ = "-l";                    /* 2 */
+
+       if (boot_task->local_initrd) {
+               s_initrd = talloc_asprintf(NULL, "--initrd=%s",
+                               boot_task->local_initrd);
+               assert(s_initrd);
+               *p++ = s_initrd;         /* 3 */
+       }
+
+       if (boot_task->local_dtb) {
+               s_dtb = talloc_asprintf(NULL, "--dtb=%s", boot_task->local_dtb);
+               assert(s_dtb);
+               *p++ = s_dtb;            /* 4 */
+       }
+
+       if (boot_task->args) {
+               s_args = talloc_asprintf(NULL, "--append=%s", boot_task->args);
+               assert(s_args);
+               *p++ = s_args;          /* 5 */
+       }
+
+       *p++ = boot_task->local_image;  /* 6 */
+       *p++ = NULL;                    /* 7 */
+
+       result = pb_run_cmd(argv, 1, boot_task->dry_run);
+
+       if (result)
+               pb_log("%s: failed: (%d)\n", __func__, result);
+
+       talloc_free(s_initrd);
+       talloc_free(s_dtb);
+       talloc_free(s_args);
+
+       return result;
+}
+
+/**
+ * kexec_reboot - Helper to boot the new kernel.
+ *
+ * Must only be called after a successful call to kexec_load().
+ */
+
+static int kexec_reboot(bool dry_run)
+{
+       int result = 0;
+       const char *argv[4];
+       const char **p;
+
+       /* First try running shutdown.  Init scripts should run 'exec -e' */
+
+       p = argv;
+       *p++ = pb_system_apps.shutdown; /* 1 */
+       *p++ =  "-r";                   /* 2 */
+       *p++ =  "now";                  /* 3 */
+       *p++ =  NULL;                   /* 4 */
+
+       result = pb_run_cmd(argv, 1, dry_run);
+
+       /* On error, force a kexec with the -e option */
+
+       if (result) {
+               p = argv;
+               *p++ = pb_system_apps.kexec;    /* 1 */
+               *p++ = "-e";                    /* 2 */
+               *p++ = NULL;                    /* 3 */
+
+               result = pb_run_cmd(argv, 1, 0);
+       }
+
+       if (result)
+               pb_log("%s: failed: (%d)\n", __func__, result);
+
+       /* okay, kexec -e -f */
+       if (result) {
+               p = argv;
+               *p++ = pb_system_apps.kexec;    /* 1 */
+               *p++ = "-e";                    /* 2 */
+               *p++ = "-f";                    /* 3 */
+               *p++ = NULL;                    /* 4 */
+
+               result = pb_run_cmd(argv, 1, 0);
+       }
+
+       if (result)
+               pb_log("%s: failed: (%d)\n", __func__, result);
+
+
+       return result;
+}
+
+static void update_status(boot_status_fn fn, void *arg, int type,
+               char *message)
+{
+       struct boot_status status;
+
+       status.type = type;
+       status.message = message;
+       status.progress = -1;
+       status.detail = NULL;
+
+       fn(arg, &status);
+}
+
+static void boot_hook_update_param(void *ctx, struct boot_task *task,
+               const char *name, const char *value)
+{
+       struct p {
+               const char *name;
+               char **p;
+       } *param, params[] = {
+               { "boot_image",         &task->local_image },
+               { "boot_initrd",        &task->local_initrd },
+               { "boot_dtb",           &task->local_dtb },
+               { "boot_args",          &task->args },
+               { NULL, NULL },
+       };
+
+       for (param = params; param->name; param++) {
+               if (strcmp(param->name, name))
+                       continue;
+
+               *param->p = talloc_strdup(ctx, value);
+               return;
+       }
+}
+
+static void boot_hook_update(void *ctx, const char *hookname,
+               struct boot_task *task, char *buf)
+{
+       char *line, *name, *val, *sep;
+       char *saveptr;
+
+       for (;; buf = NULL) {
+
+               line = strtok_r(buf, "\n", &saveptr);
+               if (!line)
+                       break;
+
+               sep = strchr(line, '=');
+               if (!sep)
+                       continue;
+
+               *sep = '\0';
+               name = line;
+               val = sep + 1;
+
+               boot_hook_update_param(ctx, task, name, val);
+
+               pb_log("boot hook %s specified %s=%s\n",
+                               hookname, name, val);
+       }
+}
+
+static void boot_hook_setenv(struct boot_task *task)
+{
+       unsetenv("boot_image");
+       unsetenv("boot_initrd");
+       unsetenv("boot_dtb");
+       unsetenv("boot_args");
+
+       setenv("boot_image", task->local_image, 1);
+       if (task->local_initrd)
+               setenv("boot_initrd", task->local_initrd, 1);
+       if (task->local_dtb)
+               setenv("boot_dtb", task->local_dtb, 1);
+       if (task->args)
+               setenv("boot_args", task->args, 1);
+}
+
+static int hook_filter(const struct dirent *dirent)
+{
+       return dirent->d_type == DT_REG || dirent->d_type == DT_LNK;
+}
+
+static int hook_cmp(const struct dirent **a, const struct dirent **b)
+{
+       return strcmp((*a)->d_name, (*b)->d_name);
+}
+
+static void run_boot_hooks(void *ctx, struct boot_task *task,
+               boot_status_fn status_fn, void *status_arg)
+{
+       struct dirent **hooks;
+       int i, n;
+
+       n = scandir(boot_hook_dir, &hooks, hook_filter, hook_cmp);
+       if (n < 1)
+               return;
+
+       update_status(status_fn, status_arg, BOOT_STATUS_INFO,
+                       "running boot hooks");
+
+       boot_hook_setenv(task);
+
+       for (i = 0; i < n; i++) {
+               const char *argv[2] = { NULL, NULL };
+               char *path, *buf;
+               int buf_len, rc;
+
+               path = join_paths(ctx, boot_hook_dir, hooks[i]->d_name);
+
+               if (access(path, X_OK))
+                       continue;
+
+               pb_log("running boot hook %s\n", hooks[i]->d_name);
+
+               argv[0] = path;
+               rc = pb_run_cmd_pipe(argv, 1, task->dry_run, ctx,
+                               &buf, &buf_len);
+
+               /* if the hook returned with BOOT_HOOK_EXIT_UPDATE,
+                * then we process stdout to look for updated params
+                */
+               if (rc == BOOT_HOOK_EXIT_UPDATE) {
+                       boot_hook_update(ctx, hooks[i]->d_name, task, buf);
+                       boot_hook_setenv(task);
+               }
+
+               talloc_free(buf);
+               talloc_free(path);
+       }
+
+       free(hooks);
+}
+
+int boot(void *ctx, struct discover_boot_option *opt, struct boot_command *cmd,
+               int dry_run, boot_status_fn status_fn, void *status_arg)
+{
+       struct boot_task boot_task;
+       struct pb_url *image, *initrd, *dtb;
+       unsigned int clean_image = 0;
+       unsigned int clean_initrd = 0;
+       unsigned int clean_dtb = 0;
+       int result;
+
+       image = NULL;
+       initrd = NULL;
+       dtb = NULL;
+       boot_task.dry_run = dry_run;
+
+       if (cmd && cmd->boot_image_file) {
+               image = pb_url_parse(opt, cmd->boot_image_file);
+       } else if (opt && opt->boot_image) {
+               image = opt->boot_image->url;
+       } else {
+               pb_log("%s: no image specified", __func__);
+               return -1;
+       }
+
+       if (cmd && cmd->initrd_file) {
+               initrd = pb_url_parse(opt, cmd->initrd_file);
+       } else if (opt && opt->initrd) {
+               initrd = opt->initrd->url;
+       }
+
+       if (cmd && cmd->dtb_file) {
+               dtb = pb_url_parse(opt, cmd->dtb_file);
+       } else if (opt && opt->dtb) {
+               dtb = opt->dtb->url;
+       }
+
+       if (cmd && cmd->boot_args) {
+               boot_task.args = talloc_strdup(ctx, cmd->boot_args);
+       } else if (opt && opt->option->boot_args) {
+               boot_task.args = talloc_strdup(ctx, opt->option->boot_args);
+       } else {
+               boot_task.args = NULL;
+       }
+
+       result = -1;
+
+       boot_task.local_initrd = NULL;
+       boot_task.local_dtb = NULL;
+
+       update_status(status_fn, status_arg, BOOT_STATUS_INFO,
+                       "loading kernel");
+       boot_task.local_image = load_url(NULL, image, &clean_image);
+       if (!boot_task.local_image) {
+               update_status(status_fn, status_arg, BOOT_STATUS_ERROR,
+                               "Couldn't load kernel image");
+               goto no_load;
+       }
+
+       if (initrd) {
+               update_status(status_fn, status_arg, BOOT_STATUS_INFO,
+                               "loading initrd");
+               boot_task.local_initrd = load_url(NULL, initrd, &clean_initrd);
+               if (!boot_task.local_initrd) {
+                       update_status(status_fn, status_arg, BOOT_STATUS_ERROR,
+                                       "Couldn't load initrd image");
+                       goto no_load;
+               }
+       }
+
+       if (dtb) {
+               update_status(status_fn, status_arg, BOOT_STATUS_INFO,
+                               "loading device tree");
+               boot_task.local_dtb = load_url(NULL, dtb, &clean_dtb);
+               if (!boot_task.local_dtb) {
+                       update_status(status_fn, status_arg, BOOT_STATUS_ERROR,
+                                       "Couldn't load device tree");
+                       goto no_load;
+               }
+       }
+
+       run_boot_hooks(ctx, &boot_task, status_fn, status_arg);
+
+       update_status(status_fn, status_arg, BOOT_STATUS_INFO,
+                       "performing kexec_load");
+
+       result = kexec_load(&boot_task);
+
+       if (result) {
+               update_status(status_fn, status_arg, BOOT_STATUS_ERROR,
+                               "kexec load failed");
+       }
+
+no_load:
+       if (clean_image)
+               unlink(boot_task.local_image);
+       if (clean_initrd)
+               unlink(boot_task.local_initrd);
+       if (clean_dtb)
+               unlink(boot_task.local_dtb);
+
+       talloc_free(boot_task.local_image);
+       talloc_free(boot_task.local_initrd);
+       talloc_free(boot_task.local_dtb);
+
+       if (!result) {
+               update_status(status_fn, status_arg, BOOT_STATUS_INFO,
+                               "performing kexec reboot");
+
+               result = kexec_reboot(boot_task.dry_run);
+
+               if (result) {
+                       update_status(status_fn, status_arg, BOOT_STATUS_ERROR,
+                                       "kexec reboot failed");
+               }
+       }
 
-       return 0;
+       return result;
 }