boot: Add efivar_get/set_uint64_le() functions

These are implemented as bit-shifting functions that allow reading
and writing UEFI variables stored as little endian 64-bit unsigned
values.

2 files changed, 65 insertions, 0 deletions

diff --git a/src/boot/efi/util.c b/src/boot/efi/util.c
index dea4872158..50ad757565 100644
--- a/src/boot/efi/util.c
+++ b/src/boot/efi/util.c
@@ -97,6 +97,32 @@ EFI_STATUS efivar_set_uint_string(const EFI_GUID *vendor, CHAR16 *name, UINTN i,
         return efivar_set(vendor, name, str, persistent);
 }
 
+EFI_STATUS efivar_set_uint32_le(const EFI_GUID *vendor, CHAR16 *name, UINT32 value, BOOLEAN persistent) {
+        UINT8 buf[4];
+
+        buf[0] = (UINT8)(value >> 0U & 0xFF);
+        buf[1] = (UINT8)(value >> 8U & 0xFF);
+        buf[2] = (UINT8)(value >> 16U & 0xFF);
+        buf[3] = (UINT8)(value >> 24U & 0xFF);
+
+        return efivar_set_raw(vendor, name, buf, sizeof(buf), persistent);
+}
+
+EFI_STATUS efivar_set_uint64_le(const EFI_GUID *vendor, CHAR16 *name, UINT64 value, BOOLEAN persistent) {
+        UINT8 buf[8];
+
+        buf[0] = (UINT8)(value >> 0U & 0xFF);
+        buf[1] = (UINT8)(value >> 8U & 0xFF);
+        buf[2] = (UINT8)(value >> 16U & 0xFF);
+        buf[3] = (UINT8)(value >> 24U & 0xFF);
+        buf[4] = (UINT8)(value >> 32U & 0xFF);
+        buf[5] = (UINT8)(value >> 40U & 0xFF);
+        buf[6] = (UINT8)(value >> 48U & 0xFF);
+        buf[7] = (UINT8)(value >> 56U & 0xFF);
+
+        return efivar_set_raw(vendor, name, buf, sizeof(buf), persistent);
+}
+
 EFI_STATUS efivar_get(const EFI_GUID *vendor, const CHAR16 *name, CHAR16 **value) {
         _cleanup_freepool_ CHAR8 *buf = NULL;
         EFI_STATUS err;
@@ -143,6 +169,41 @@ EFI_STATUS efivar_get_uint_string(const EFI_GUID *vendor, const CHAR16 *name, UI
         return err;
 }
 
+EFI_STATUS efivar_get_uint32_le(const EFI_GUID *vendor, const CHAR16 *name, UINT32 *ret) {
+        _cleanup_freepool_ CHAR8 *buf = NULL;
+        UINTN size;
+        EFI_STATUS err;
+
+        err = efivar_get_raw(vendor, name, &buf, &size);
+        if (!EFI_ERROR(err) && ret) {
+                if (size != sizeof(UINT32))
+                        return EFI_BUFFER_TOO_SMALL;
+
+                *ret = (UINT32) buf[0] << 0U | (UINT32) buf[1] << 8U | (UINT32) buf[2] << 16U |
+                        (UINT32) buf[3] << 24U;
+        }
+
+        return err;
+}
+
+EFI_STATUS efivar_get_uint64_le(const EFI_GUID *vendor, const CHAR16 *name, UINT64 *ret) {
+        _cleanup_freepool_ CHAR8 *buf = NULL;
+        UINTN size;
+        EFI_STATUS err;
+
+        err = efivar_get_raw(vendor, name, &buf, &size);
+        if (!EFI_ERROR(err) && ret) {
+                if (size != sizeof(UINT64))
+                        return EFI_BUFFER_TOO_SMALL;
+
+                *ret = (UINT64) buf[0] << 0U | (UINT64) buf[1] << 8U | (UINT64) buf[2] << 16U |
+                        (UINT64) buf[3] << 24U | (UINT64) buf[4] << 32U | (UINT64) buf[5] << 40U |
+                        (UINT64) buf[6] << 48U | (UINT64) buf[7] << 56U;
+        }
+
+        return err;
+}
+
 EFI_STATUS efivar_get_raw(const EFI_GUID *vendor, const CHAR16 *name, CHAR8 **buffer, UINTN *size) {
         _cleanup_freepool_ CHAR8 *buf = NULL;
         UINTN l;
diff --git a/src/boot/efi/util.h b/src/boot/efi/util.h
index f0e9610629..313d6697d2 100644
--- a/src/boot/efi/util.h
+++ b/src/boot/efi/util.h
@@ -24,11 +24,15 @@ UINT64 time_usec(void);
 EFI_STATUS efivar_set(const EFI_GUID *vendor, const CHAR16 *name, const CHAR16 *value, BOOLEAN persistent);
 EFI_STATUS efivar_set_raw(const EFI_GUID *vendor, const CHAR16 *name, const VOID *buf, UINTN size, BOOLEAN persistent);
 EFI_STATUS efivar_set_uint_string(const EFI_GUID *vendor, CHAR16 *name, UINTN i, BOOLEAN persistent);
+EFI_STATUS efivar_set_uint32_le(const EFI_GUID *vendor, CHAR16 *NAME, UINT32 value, BOOLEAN persistent);
+EFI_STATUS efivar_set_uint64_le(const EFI_GUID *vendor, CHAR16 *name, UINT64 value, BOOLEAN persistent);
 VOID efivar_set_time_usec(const EFI_GUID *vendor, CHAR16 *name, UINT64 usec);
 
 EFI_STATUS efivar_get(const EFI_GUID *vendor, const CHAR16 *name, CHAR16 **value);
 EFI_STATUS efivar_get_raw(const EFI_GUID *vendor, const CHAR16 *name, CHAR8 **buffer, UINTN *size);
 EFI_STATUS efivar_get_uint_string(const EFI_GUID *vendor, const CHAR16 *name, UINTN *i);
+EFI_STATUS efivar_get_uint32_le(const EFI_GUID *vendor, const CHAR16 *name, UINT32 *ret);
+EFI_STATUS efivar_get_uint64_le(const EFI_GUID *vendor, const CHAR16 *name, UINT64 *ret);
 EFI_STATUS efivar_get_boolean_u8(const EFI_GUID *vendor, const CHAR16 *name, BOOLEAN *ret);
 
 CHAR8 *strchra(CHAR8 *s, CHAR8 c);