[PATCH v4 09/16] efi_loader: set up secure boot

[AKASHI Takahiro]

The following variable is exported as UEFI specification defines:
SignatureSupport: array of GUIDs representing the type of signatures
                      supported by the platform firmware

Signed-off-by: AKASHI Takahiro <takahiro.akashi at linaro.org>
---
 lib/efi_loader/efi_setup.c | 38 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/lib/efi_loader/efi_setup.c b/lib/efi_loader/efi_setup.c
index de7b616c6daa..50cef1b4dfde 100644
--- a/lib/efi_loader/efi_setup.c
+++ b/lib/efi_loader/efi_setup.c
@@ -82,6 +82,39 @@ out:
 	return ret;
 }
 
+#ifdef CONFIG_EFI_SECURE_BOOT
+/**
+ * efi_init_secure_boot - initialize secure boot state
+ *
+ * Return:	EFI_SUCCESS on success, status code (negative) on error
+ */
+static efi_status_t efi_init_secure_boot(void)
+{
+	efi_guid_t signature_types[] = {
+		EFI_CERT_SHA256_GUID,
+		EFI_CERT_X509_GUID,
+	};
+	efi_status_t ret;
+
+	/* TODO: read-only */
+	ret = EFI_CALL(efi_set_variable(L"SignatureSupport",
+					&efi_global_variable_guid,
+					EFI_VARIABLE_BOOTSERVICE_ACCESS
+					 | EFI_VARIABLE_RUNTIME_ACCESS,
+					sizeof(signature_types),
+					&signature_types));
+	if (ret != EFI_SUCCESS)
+		printf("EFI: cannot initialize SignatureSupport variable\n");
+
+	return ret;
+}
+#else
+static efi_status_t efi_init_secure_boot(void)
+{
+	return EFI_SUCCESS;
+}
+#endif /* CONFIG_EFI_SECURE_BOOT */
+
 /**
  * efi_init_obj_list() - Initialize and populate EFI object list
  *
@@ -122,6 +155,11 @@ efi_status_t efi_init_obj_list(void)
 	if (ret != EFI_SUCCESS)
 		goto out;
 
+	/* Secure boot */
+	ret = efi_init_secure_boot();
+	if (ret != EFI_SUCCESS)
+		goto out;
+
 	/* Indicate supported runtime services */
 	ret = efi_init_runtime_supported();
 	if (ret != EFI_SUCCESS)
-- 
2.24.0