Files
OpenCellular/include/ccd_config.h
Vadim Bendebury 91c1b0abab ccd: restrict password setting to allowed states
Setting password should be allowed only after the owner logged in for
the first time and before they log out or someone else logs in.

Once any other user but the owner logs in, it should become impossible
to set password until the device is reset.

As proposed here, this would apply to both attempts to set password
through crosh and Cr50 console.

Password handling on Cr50 passes the following states:

- password setting is not allowed after Cr50 reset until an upstart
  (as opposed to resume) TPM startup happens, as signalled by the TPM
  callback.  After the proper TPM reset the state changes to
  'POST_RESET_STATE' which means that the device was just
  reset/rebooted (not resumed) and no user logged in yet.

- if the owner logs in in this state, the state changes to
  'PASSWORD_ALLOWED_STATE'. The owner can open crosh session and set
  the password.

- when the owner logs out or any user but the owner logs in, the state
  changes to PASSWORD_NOT_ALLOWED_STATE and does not change until TPM
  is reset. This makes sure that password can be set only by the owner
  and only before anybody else logged in.

Separate changes to the TPM library code make sure that TPM reset is
reported through the platform layer, so that POST_RESET_STATE is
entered.

BRANCH=cr50
BUG=b:67007578
TEST=with the rest of the infrastructure in place verified that
     password can be set only when the owner logged in for the first
     time before anybody else logs in or the owner logs out.

Change-Id: Ieaa3dc8ff9d2e43ae11151eb31173220f5c75b58
Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/804141
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Reviewed-by: Andrey Pronin <apronin@chromium.org>
2017-12-11 15:16:21 -08:00

186 lines
4.6 KiB
C

/* Copyright 2017 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.
*
* Case Closed Debugging configuration
*/
#ifndef __CROS_EC_CCD_CONFIG_H
#define __CROS_EC_CCD_CONFIG_H
/* Case-closed debugging state */
enum ccd_state {
CCD_STATE_LOCKED = 0,
CCD_STATE_UNLOCKED,
CCD_STATE_OPENED,
/* Number of CCD states */
CCD_STATE_COUNT
};
/* Flags */
enum ccd_flag {
/* Flags that can only be set internally; fill from bottom up */
/*
* Test lab mode is enabled. This MUST be in the first byte so that
* it's in a constant position across all versions of CCD config.
*
* Note: This is used internally by CCD config. Do NOT test this
* to control other things; use capabilities for those.
*/
CCD_FLAG_TEST_LAB = (1 << 0),
/*
* What state were we in when the password was set?
* (0=opened, 1=unlocked)
*/
CCD_FLAG_PASSWORD_SET_WHEN_UNLOCKED = (1 << 1),
/* (flags in the middle are unused) */
/* Flags that can be set via ccd_set_flags(); fill from top down */
/* Override write protect at boot */
CCD_FLAG_OVERRIDE_WP_AT_BOOT = (1 << 22),
/*
* If overriding WP at boot, set it to what value
* (0=disabled, 1=enabled)
*/
CCD_FLAG_OVERRIDE_WP_STATE_ENABLED = (1 << 23),
};
/* Capabilities */
enum ccd_capability {
/* UARTs to/from AP and EC */
CCD_CAP_GSC_RX_AP_TX = 0,
CCD_CAP_GSC_TX_AP_RX = 1,
CCD_CAP_GSC_RX_EC_TX = 2,
CCD_CAP_GSC_TX_EC_RX = 3,
/* Access to AP SPI flash */
CCD_CAP_AP_FLASH = 4,
/* Access to EC flash (SPI or internal) */
CCD_CAP_EC_FLASH = 5,
/* Override WP temporarily or at boot */
CCD_CAP_OVERRIDE_WP = 6,
/* Reboot EC or AP */
CCD_CAP_REBOOT_EC_AP = 7,
/* GSC restricted console commands */
CCD_CAP_GSC_RESTRICTED_CONSOLE = 8,
/* Allow ccd-unlock or ccd-open without AP reboot */
CCD_CAP_UNLOCK_WITHOUT_AP_REBOOT = 9,
/* Allow ccd-unlock or ccd-open without short physical presence */
CCD_CAP_UNLOCK_WITHOUT_SHORT_PP = 10,
/* Allow ccd-open without wiping TPM data */
CCD_CAP_OPEN_WITHOUT_TPM_WIPE = 11,
/* Allow ccd-open without long physical presence */
CCD_CAP_OPEN_WITHOUT_LONG_PP = 12,
/* Allow removing the battery to bypass physical presence requirement */
CCD_CAP_REMOVE_BATTERY_BYPASSES_PP = 13,
/* Allow GSC firmware update without wiping TPM data */
CCD_CAP_GSC_FW_UPDATE_WITHOUT_TPM_WIPE = 14,
/* Access to I2C via USB */
CCD_CAP_I2C = 15,
/* Number of currently defined capabilities */
CCD_CAP_COUNT
};
/**
* Initialize CCD configuration at boot.
*
* This must be called before any command which gets/sets the configuration.
*
* @param state Initial case-closed debugging state. This should be
* CCD_STATE_LOCKED unless this is a debug build, or if
* a previous value is being restored after a low-power
* resume.
*/
void ccd_config_init(enum ccd_state state);
/**
* Get a single CCD flag.
*
* @param flag Flag to get
* @return 1 if flag is set, 0 if flag is clear
*/
int ccd_get_flag(enum ccd_flag flag);
/**
* Set a single CCD flag.
*
* @param flag Flag to set
* @param value New value for flag (0=clear, non-zero=set)
* @return EC_SUCCESS or non-zero error code.
*/
int ccd_set_flag(enum ccd_flag flag, int value);
/**
* Check if a CCD capability is enabled in the current CCD mode.
*
* @param cap Capability to check
* @return 1 if capability is enabled, 0 if disabled
*/
int ccd_is_cap_enabled(enum ccd_capability cap);
/**
* Get the current CCD state.
*
* This is intended for use by the board if it needs to back up the CCD state
* across low-power states and then restore it when calling ccd_config_init().
* Do NOT use this to gate debug capabilities; use ccd_is_cap_enabled() or
* ccd_get_flag() instead.
*
* @return The current CCD state.
*/
enum ccd_state ccd_get_state(void);
/**
* Force CCD disabled.
*
* This should be called if security checks fail and for some reason the board
* can't immediately reboot. It locks CCD and disables all CCD capabilities
* until reboot.
*/
void ccd_disable(void);
/* Flags for ccd_reset_config() */
enum ccd_reset_config_flags {
/* Also reset test lab flag */
CCD_RESET_TEST_LAB = (1 << 0),
/* Only reset Always/UnlessLocked settings */
CCD_RESET_UNLOCKED_ONLY = (1 << 1),
/* Use RMA/factory defaults */
CCD_RESET_RMA = (1 << 2)
};
/**
* Reset CCD config to the desired state.
*
* @param flags Reset flags (see enum ccd_reset_config_flags)
* @return EC_SUCCESS, or non-zero if error.
*/
int ccd_reset_config(unsigned int flags);
/**
* Inform CCD about TPM reset so that the password management state machine
* can be restarted.
*/
void ccd_tpm_reset_callback(void);
#endif /* __CROS_EC_CCD_CONFIG_H */