diff options
Diffstat (limited to 'MokManager.c')
| -rw-r--r-- | MokManager.c | 56 |
1 files changed, 48 insertions, 8 deletions
diff --git a/MokManager.c b/MokManager.c index 3928196f..3a9e7ba9 100644 --- a/MokManager.c +++ b/MokManager.c @@ -24,8 +24,6 @@ #define SHIM_VENDOR L"Shim" #endif -#define EFI_VARIABLE_APPEND_WRITE 0x00000040 - EFI_GUID SHIM_LOCK_GUID = { 0x605dab50, 0xe046, 0x4300, {0xab, 0xb6, 0x3d, 0xd8, 0x10, 0xdd, 0x8b, 0x23} }; EFI_GUID EFI_CERT_SHA224_GUID = { 0xb6e5233, 0xa65c, 0x44c9, {0x94, 0x7, 0xd9, 0xab, 0x83, 0xbf, 0xc8, 0xbd} }; EFI_GUID EFI_CERT_SHA384_GUID = { 0xff3e5307, 0x9fd0, 0x48c9, {0x85, 0xf1, 0x8a, 0xd5, 0x6c, 0x70, 0x1e, 0x1} }; @@ -864,6 +862,53 @@ static EFI_STATUS match_password (PASSWORD_CRYPT *pw_crypt, return EFI_SUCCESS; } +static EFI_STATUS write_db (CHAR16 *db_name, void *MokNew, UINTN MokNewSize) +{ + EFI_GUID shim_lock_guid = SHIM_LOCK_GUID; + EFI_STATUS status; + UINT32 attributes; + void *old_data = NULL; + void *new_data = NULL; + UINTN old_size; + UINTN new_size; + + status = get_variable_attr(db_name, (UINT8 **)&old_data, &old_size, + shim_lock_guid, &attributes); + if (EFI_ERROR(status) && status != EFI_NOT_FOUND) { + return status; + } + + /* Check if the old db is compromised or not */ + if (attributes & EFI_VARIABLE_RUNTIME_ACCESS) { + FreePool(old_data); + old_data = NULL; + old_size = 0; + } + + new_size = old_size + MokNewSize; + new_data = AllocatePool(new_size); + if (new_data == NULL) { + status = EFI_OUT_OF_RESOURCES; + goto out; + } + + CopyMem(new_data, old_data, old_size); + CopyMem(new_data + old_size, MokNew, MokNewSize); + + status = uefi_call_wrapper(RT->SetVariable, 5, db_name, + &shim_lock_guid, + EFI_VARIABLE_NON_VOLATILE + | EFI_VARIABLE_BOOTSERVICE_ACCESS, + new_size, new_data); + +out: + if (old_size > 0) { + FreePool(old_data); + } + + return status; +} + static EFI_STATUS store_keys (void *MokNew, UINTN MokNewSize, int authenticate, BOOLEAN MokX) { @@ -918,12 +963,7 @@ static EFI_STATUS store_keys (void *MokNew, UINTN MokNewSize, int authenticate, 0, NULL); } else { /* Write new MOK */ - efi_status = uefi_call_wrapper(RT->SetVariable, 5, db_name, - &shim_lock_guid, - EFI_VARIABLE_NON_VOLATILE - | EFI_VARIABLE_BOOTSERVICE_ACCESS - | EFI_VARIABLE_APPEND_WRITE, - MokNewSize, MokNew); + efi_status = write_db(db_name, MokNew, MokNewSize); } if (efi_status != EFI_SUCCESS) { |