Add support for forcing EFI installation to the removable media path

Add an extra option to grub-install "--force-extra-removable". On EFI
platforms, this will cause an extra copy of the grub-efi image to be
written to the appropriate removable media patch
/boot/efi/EFI/BOOT/BOOT$ARCH.EFI as well. This will help with broken
UEFI implementations where the firmware does not work when configured
with new boot paths.

Signed-off-by: Steve McIntyre <93sam@debian.org>
Bug-Debian: https://bugs.debian.org/767037 https://bugs.debian.org/773092
Forwarded: Not yet
Last-Update: 2021-09-24

Patch-Name: grub-install-extra-removable.patch

diff --git a/util/grub-install.c b/util/grub-install.c
index 2304cc5c4f5afe9b827024adb83293ce2a97c0af..b51fe471082b0bfbfb134036fe7054c30fce33b7 100644 (file)
--- a/util/grub-install.c
+++ b/util/grub-install.c
@@ -56,6 +56,7 @@
 
 static char *target;
 static int removable = 0;
+static int force_extra_removable = 0;
 static int recheck = 0;
 static int update_nvram = 1;
 static char *install_device = NULL;
@@ -113,7 +114,8 @@ enum
     OPTION_LABEL_BGCOLOR,
     OPTION_PRODUCT_VERSION,
     OPTION_UEFI_SECURE_BOOT,
-    OPTION_NO_UEFI_SECURE_BOOT
+    OPTION_NO_UEFI_SECURE_BOOT,
+    OPTION_FORCE_EXTRA_REMOVABLE
   };
 
 static int fs_probe = 1;
@@ -216,6 +218,10 @@ argp_parser (int key, char *arg, struct argp_state *state)
       removable = 1;
       return 0;
 
+    case OPTION_FORCE_EXTRA_REMOVABLE:
+      force_extra_removable = 1;
+      return 0;
+
     case OPTION_ALLOW_FLOPPY:
       allow_floppy = 1;
       return 0;
@@ -322,6 +328,9 @@ static struct argp_option options[] = {
    N_("do not install an image usable with UEFI Secure Boot, even if the "
       "system was currently started using it. "
       "This option is only available on EFI."), 2},
+  {"force-extra-removable", OPTION_FORCE_EXTRA_REMOVABLE, 0, 0,
+   N_("force installation to the removable media path also. "
+      "This option is only available on EFI."), 2},
   {0, 0, 0, 0, 0, 0}
 };
 
@@ -847,6 +856,91 @@ fill_core_services (const char *core_services)
   free (sysv_plist);
 }
 
+/* Helper routine for also_install_removable() below. Walk through the
+   specified dir, looking to see if there is a file/dir that matches
+   the search string exactly, but in a case-insensitive manner. If so,
+   return a copy of the exact file/dir that *does* exist. If not,
+   return NULL */
+static char *
+check_component_exists(const char *dir,
+                      const char *search)
+{
+  grub_util_fd_dir_t d;
+  grub_util_fd_dirent_t de;
+  char *found = NULL;
+
+  d = grub_util_fd_opendir (dir);
+  if (!d)
+    grub_util_error (_("cannot open directory `%s': %s"),
+                    dir, grub_util_fd_strerror ());
+
+  while ((de = grub_util_fd_readdir (d)))
+    {
+      if (strcasecmp (de->d_name, search) == 0)
+       {
+         found = xstrdup (de->d_name);
+         break;
+       }
+    }
+  grub_util_fd_closedir (d);
+  return found;
+}
+
+/* Some complex directory-handling stuff in here, to cope with
+ * case-insensitive FAT/VFAT filesystem semantics. Ugh. */
+static void
+also_install_removable(const char *src,
+                      const char *base_efidir,
+                      const char *efi_suffix_upper)
+{
+  char *efi_file = NULL;
+  char *dst = NULL;
+  char *cur = NULL;
+  char *found = NULL;
+
+  if (!efi_suffix_upper)
+    grub_util_error ("%s", _("efi_suffix_upper not set"));
+  efi_file = xasprintf ("BOOT%s.EFI", efi_suffix_upper);
+
+  /* We need to install in $base_efidir/EFI/BOOT/$efi_file, but we
+   * need to cope with case-insensitive stuff here. Build the path one
+   * component at a time, checking for existing matches each time. */
+
+  /* Look for "EFI" in base_efidir. Make it if it does not exist in
+   * some form. */
+  found = check_component_exists(base_efidir, "EFI");
+  if (found == NULL)
+    found = xstrdup("EFI");
+  dst = grub_util_path_concat (2, base_efidir, found);
+  cur = xstrdup (dst);
+  free (dst);
+  free (found);
+  grub_install_mkdir_p (cur);
+
+  /* Now BOOT */
+  found = check_component_exists(cur, "BOOT");
+  if (found == NULL)
+    found = xstrdup("BOOT");
+  dst = grub_util_path_concat (2, cur, found);
+  cur = xstrdup (dst);
+  free (dst);
+  free (found);
+  grub_install_mkdir_p (cur);
+
+  /* Now $efi_file */
+  found = check_component_exists(cur, efi_file);
+  if (found == NULL)
+    found = xstrdup(efi_file);
+  dst = grub_util_path_concat (2, cur, found);
+  cur = xstrdup (dst);
+  free (dst);
+  free (found);
+  grub_install_copy_file (src, cur, 1);
+
+  free (cur);
+  free (efi_file);
+}
+
 int
 main (int argc, char *argv[])
 {
@@ -864,6 +958,7 @@ main (int argc, char *argv[])
   char *relative_grubdir;
   char **efidir_device_names = NULL;
   grub_device_t efidir_grub_dev = NULL;
+  char *base_efidir = NULL;
   char *efidir_grub_devname;
   int efidir_is_mac = 0;
   int is_prep = 0;
@@ -896,6 +991,9 @@ main (int argc, char *argv[])
       bootloader_id = xstrdup ("grub");
     }
 
+  if (removable && force_extra_removable)
+    grub_util_error (_("Invalid to use both --removable and --force_extra_removable"));
+
   if (!grub_install_source_directory)
     {
       if (!target)
@@ -1115,6 +1213,8 @@ main (int argc, char *argv[])
       if (!efidir_is_mac && grub_strcmp (fs->name, "fat") != 0)
        grub_util_error (_("%s doesn't look like an EFI partition"), efidir);
 
+      base_efidir = xstrdup(efidir);
+
       /* The EFI specification requires that an EFI System Partition must
         contain an "EFI" subdirectory, and that OS loaders are stored in
         subdirectories below EFI.  Vendors are expected to pick names that do
@@ -2048,9 +2148,15 @@ main (int argc, char *argv[])
            fprintf (config_dst_f, "configfile $prefix/grub.cfg\n");
            fclose (config_dst_f);
            free (config_dst);
+           if (force_extra_removable)
+             also_install_removable(efi_signed, base_efidir, efi_suffix_upper);
          }
        else
-         grub_install_copy_file (imgfile, dst, 1);
+         {
+           grub_install_copy_file (imgfile, dst, 1);
+           if (force_extra_removable)
+             also_install_removable(imgfile, base_efidir, efi_suffix_upper);
+         }
 
        grub_set_install_backup_ponr ();