| /* Copyright (c) 2013 The Chromium OS Authors. All rights reserved. |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| * |
| * High-level firmware wrapper API - entry points for init, firmware selection |
| */ |
| |
| #include "sysincludes.h" |
| |
| #include "gbb_header.h" |
| #include "load_firmware_fw.h" |
| #include "rollback_index.h" |
| #include "tpm_bootmode.h" |
| #include "utility.h" |
| #include "vboot_api.h" |
| #include "vboot_common.h" |
| #include "vboot_nvstorage.h" |
| |
| VbError_t VbSelectFirmware(VbCommonParams *cparams, |
| VbSelectFirmwareParams *fparams) |
| { |
| VbSharedDataHeader *shared = |
| (VbSharedDataHeader *)cparams->shared_data_blob; |
| VbNvContext vnc; |
| VbError_t retval = VBERROR_UNKNOWN; /* Default to error */ |
| int is_rec = (shared->recovery_reason ? 1 : 0); |
| int is_dev = (shared->flags & VBSD_BOOT_DEV_SWITCH_ON ? 1 : 0); |
| uint32_t tpm_status = 0; |
| |
| /* Start timer */ |
| shared->timer_vb_select_firmware_enter = VbExGetTimer(); |
| |
| /* Load NV storage */ |
| VbExNvStorageRead(vnc.raw); |
| VbNvSetup(&vnc); |
| |
| if (is_rec) { |
| /* |
| * Recovery is requested; go straight to recovery without |
| * checking the RW firmware. |
| */ |
| VBDEBUG(("VbSelectFirmware() detected recovery request\n")); |
| |
| /* Go directly to recovery mode */ |
| fparams->selected_firmware = VB_SELECT_FIRMWARE_RECOVERY; |
| } else { |
| /* Chain to LoadFirmware() */ |
| retval = LoadFirmware(cparams, fparams, &vnc); |
| |
| /* Exit if we failed to find an acceptable firmware */ |
| if (VBERROR_SUCCESS != retval) |
| goto VbSelectFirmware_exit; |
| |
| /* Translate the selected firmware path */ |
| if (shared->flags & VBSD_LF_USE_RO_NORMAL) { |
| /* Request the read-only normal/dev code path */ |
| fparams->selected_firmware = |
| VB_SELECT_FIRMWARE_READONLY; |
| } else if (0 == shared->firmware_index) |
| fparams->selected_firmware = VB_SELECT_FIRMWARE_A; |
| else { |
| fparams->selected_firmware = VB_SELECT_FIRMWARE_B; |
| } |
| |
| /* Update TPM if necessary */ |
| if (shared->fw_version_tpm_start < shared->fw_version_tpm) { |
| tpm_status = |
| RollbackFirmwareWrite(shared->fw_version_tpm); |
| if (0 != tpm_status) { |
| VBDEBUG(("Can't write FW version to TPM.\n")); |
| VbNvSet(&vnc, VBNV_RECOVERY_REQUEST, |
| VBNV_RECOVERY_RO_TPM_W_ERROR); |
| retval = VBERROR_TPM_WRITE_FIRMWARE; |
| goto VbSelectFirmware_exit; |
| } |
| } |
| |
| /* Lock firmware versions in TPM */ |
| tpm_status = RollbackFirmwareLock(); |
| if (0 != tpm_status) { |
| VBDEBUG(("Unable to lock firmware version in TPM.\n")); |
| VbNvSet(&vnc, VBNV_RECOVERY_REQUEST, |
| VBNV_RECOVERY_RO_TPM_L_ERROR); |
| retval = VBERROR_TPM_LOCK_FIRMWARE; |
| goto VbSelectFirmware_exit; |
| } |
| } |
| |
| /* |
| * At this point, we have a good idea of how we are going to |
| * boot. Update the TPM with this state information. |
| */ |
| tpm_status = SetTPMBootModeState(is_dev, is_rec, |
| shared->fw_keyblock_flags); |
| if (0 != tpm_status) { |
| VBDEBUG(("Can't update the TPM with boot mode information.\n")); |
| if (!is_rec) { |
| VbNvSet(&vnc, VBNV_RECOVERY_REQUEST, |
| VBNV_RECOVERY_RO_TPM_U_ERROR); |
| retval = VBERROR_TPM_SET_BOOT_MODE_STATE; |
| goto VbSelectFirmware_exit; |
| } |
| } |
| |
| /* Success! */ |
| retval = VBERROR_SUCCESS; |
| |
| VbSelectFirmware_exit: |
| |
| /* Save NV storage */ |
| VbNvTeardown(&vnc); |
| if (vnc.raw_changed) |
| VbExNvStorageWrite(vnc.raw); |
| |
| /* Stop timer */ |
| shared->timer_vb_select_firmware_exit = VbExGetTimer(); |
| |
| /* Should always have a known error code */ |
| VbAssert(VBERROR_UNKNOWN != retval); |
| |
| return retval; |
| } |