From c31fc5aa0ded9ce1e774d0a3526cfee19be1b77f Mon Sep 17 00:00:00 2001 From: Michael Chang Date: Mon, 7 Feb 2022 20:49:01 +0800 Subject: [PATCH 3/5] grub-install: support prep environment block The grub-install can be instructed to create environment block at end of PReP paritition with probed device identities and properties in variables to facilitate root device discovery. So far these variables are defined for this purpose: ENV_FS_UUID - The filesystem uuid for the grub root device ENV_CRYPTO_UUID - The crytodisk uuid for the grub root device separated by space ENV_GRUB_DIR - The path to grub prefix directory ENV_HINT - The recommended hint string for searching root device The size of environment block is defined in GRUB_ENVBLK_PREP_SIZE which is 4096 bytes and can be extended in the future. v2: Improve detection of ENV_CRYPTO_UUID by traversing all members of the logical disk and utilize a space as a separator when multiple UUIDs are found (bsc#1216075). Signed-off-by: Michael Chang --- include/grub/lib/envblk.h | 3 +++ util/grub-install.c | 38 ++++++++++++++++++++++++++++++++++++++ 2 files changed, 41 insertions(+) --- a/include/grub/lib/envblk.h +++ b/include/grub/lib/envblk.h @@ -24,6 +24,9 @@ #ifndef ASM_FILE +#include +#define GRUB_ENVBLK_PREP_SIZE (GRUB_DISK_SECTOR_SIZE << 3) + struct grub_envblk { char *buf; --- a/util/grub-install.c +++ b/util/grub-install.c @@ -43,6 +43,7 @@ #include #include #include +#include #include @@ -609,6 +610,41 @@ } } +static char * +cryptodisk_uuids (grub_disk_t disk, int in_recurse) +{ + grub_disk_memberlist_t list = NULL, tmp; + static char *ret; + + if (!in_recurse) + ret = NULL; + + if (disk->dev->disk_memberlist) + list = disk->dev->disk_memberlist (disk); + + while (list) + { + ret = cryptodisk_uuids (list->disk, 1); + tmp = list->next; + free (list); + list = tmp; + } + + if (disk->dev->id == GRUB_DISK_DEVICE_CRYPTODISK_ID) + { + if (!ret) + ret = grub_strdup (grub_util_cryptodisk_get_uuid (disk)); + else + { + char *s = grub_xasprintf ("%s %s", grub_util_cryptodisk_get_uuid (disk), ret); + grub_free (ret); + ret = s; + } + } + + return ret; +} + static int is_same_disk (const char *a, const char *b) { @@ -2138,6 +2174,43 @@ if (write_to_disk (ins_dev, imgfile)) grub_util_error ("%s", _("failed to copy Grub to the PReP partition")); grub_set_install_backup_ponr (); + + if ((signed_grub_mode >= SIGNED_GRUB_FORCE) || ((signed_grub_mode == SIGNED_GRUB_AUTO) && (ppc_sb_state > 0))) + { + char *uuid = NULL; + grub_envblk_t envblk = NULL; + char *buf; + char *cryptouuid = NULL; + + if (grub_dev->disk) + cryptouuid = cryptodisk_uuids (grub_dev->disk, 0); + + if (grub_fs->fs_uuid && grub_fs->fs_uuid (grub_dev, &uuid)) + { + grub_print_error (); + grub_errno = 0; + uuid = NULL; + } + buf = grub_envblk_buf (GRUB_ENVBLK_PREP_SIZE); + envblk = grub_envblk_open (buf, GRUB_ENVBLK_PREP_SIZE); + if (uuid) + grub_envblk_set (envblk, "ENV_FS_UUID", uuid); + if (cryptouuid) + grub_envblk_set (envblk, "ENV_CRYPTO_UUID", cryptouuid); + if (relative_grubdir) + grub_envblk_set (envblk, "ENV_GRUB_DIR", relative_grubdir); + if (have_abstractions) + grub_envblk_set (envblk, "ENV_HINT", grub_dev->disk->name); + if (use_relative_path_on_btrfs) + grub_envblk_set (envblk, "btrfs_relative_path", "1"); + if (envblk) + { + fprintf (stderr, _("Write environment block to PReP.\n")); + if (grub_disk_write_tail (ins_dev->disk, envblk->size, envblk->buf)) + grub_util_error ("%s", _("failed to write environment block to the PReP partition")); + } + grub_envblk_close (envblk); + } grub_device_close (ins_dev); if (update_nvram) grub_install_register_ieee1275 (1, grub_util_get_os_disk (install_device),