[PATCH 1/6] efistub: pass uefi secureboot flag via fdt params

From: Chester Lin
Date: Fri Sep 04 2020 - 03:30:42 EST


Add a new UEFI parameter: "linux,uefi-secure-boot" in fdt boot params
as other architectures have done in their own boot data. For example,
the boot_params->secure_boot in x86.

Signed-off-by: Chester Lin <clin@xxxxxxxx>
---
drivers/firmware/efi/libstub/fdt.c | 39 +++++++++++++++++++++++++++++-
1 file changed, 38 insertions(+), 1 deletion(-)

diff --git a/drivers/firmware/efi/libstub/fdt.c b/drivers/firmware/efi/libstub/fdt.c
index 11ecf3c4640e..c9a341e4715f 100644
--- a/drivers/firmware/efi/libstub/fdt.c
+++ b/drivers/firmware/efi/libstub/fdt.c
@@ -136,6 +136,10 @@ static efi_status_t update_fdt(void *orig_fdt, unsigned long orig_fdt_size,
if (status)
goto fdt_set_fail;

+ status = fdt_setprop_var(fdt, node, "linux,uefi-secure-boot", fdt_val32);
+ if (status)
+ goto fdt_set_fail;
+
if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) {
efi_status_t efi_status;

@@ -199,6 +203,24 @@ static efi_status_t update_fdt_memmap(void *fdt, struct efi_boot_memmap *map)
return EFI_SUCCESS;
}

+static efi_status_t update_fdt_secboot(void *fdt, u32 secboot)
+{
+ int node = fdt_path_offset(fdt, "/chosen");
+ u32 fdt_val32;
+ int err;
+
+ if (node < 0)
+ return EFI_LOAD_ERROR;
+
+ fdt_val32 = cpu_to_fdt32(secboot);
+
+ err = fdt_setprop_inplace_var(fdt, node, "linux,uefi-secure-boot", fdt_val32);
+ if (err)
+ return EFI_LOAD_ERROR;
+
+ return EFI_SUCCESS;
+}
+
struct exit_boot_struct {
efi_memory_desc_t *runtime_map;
int *runtime_entry_count;
@@ -208,6 +230,9 @@ struct exit_boot_struct {
static efi_status_t exit_boot_func(struct efi_boot_memmap *map,
void *priv)
{
+ efi_status_t status;
+ enum efi_secureboot_mode secboot_status;
+ u32 secboot_var = 0;
struct exit_boot_struct *p = priv;
/*
* Update the memory map with virtual addresses. The function will also
@@ -217,7 +242,19 @@ static efi_status_t exit_boot_func(struct efi_boot_memmap *map,
efi_get_virtmap(*map->map, *map->map_size, *map->desc_size,
p->runtime_map, p->runtime_entry_count);

- return update_fdt_memmap(p->new_fdt_addr, map);
+ status = update_fdt_memmap(p->new_fdt_addr, map);
+
+ if (status != EFI_SUCCESS)
+ return status;
+
+ secboot_status = efi_get_secureboot();
+
+ if (secboot_status == efi_secureboot_mode_enabled)
+ secboot_var = 1;
+
+ status = update_fdt_secboot(p->new_fdt_addr, secboot_var);
+
+ return status;
}

#ifndef MAX_FDT_SIZE
--
2.26.1