efi_loader: hash the image once before checking against db/dbx
We don't have to recalculate the image hash every time we check against a
new db/dbx entry. So let's add a flag forcing it to run once since we only
support sha256 hashes
Suggested-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
diff --git a/lib/efi_loader/efi_signature.c b/lib/efi_loader/efi_signature.c
index eb6886c..1bd1fdc 100644
--- a/lib/efi_loader/efi_signature.c
+++ b/lib/efi_loader/efi_signature.c
@@ -192,6 +192,7 @@
void *hash = NULL;
size_t size = 0;
bool found = false;
+ bool hash_done = false;
EFI_PRINT("%s: Enter, %p, %p\n", __func__, regs, db);
@@ -214,10 +215,12 @@
if (guidcmp(&siglist->sig_type, &efi_guid_sha256))
continue;
- if (!efi_hash_regions(regs->reg, regs->num, &hash, &size)) {
+ if (!hash_done &&
+ !efi_hash_regions(regs->reg, regs->num, &hash, &size)) {
EFI_PRINT("Digesting an image failed\n");
break;
}
+ hash_done = true;
for (sig_data = siglist->sig_data_list; sig_data;
sig_data = sig_data->next) {