kern/include/crypto/2misc.h

/* Copyright (c) 2014 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.
 *
 * Misc functions which need access to vb2_context but are not public APIs
 */

#pragma once

#include "2api.h"

struct vb2_gbb_header;
struct vb2_workbuf;

/**
 * Get the shared data pointer from the vboot context
 *
 * @param ctx		Vboot context
 * @return The shared data pointer.
 */
static __inline struct vb2_shared_data *vb2_get_sd(struct vb2_context *ctx) {
	return (struct vb2_shared_data *)ctx->workbuf;
}

/**
 * Validate gbb signature (the magic number)
 *
 * @param sig		Pointer to the signature bytes to validate
 * @return VB2_SUCCESS if valid or non-zero if error.
 */
int vb2_validate_gbb_signature(uint8_t *sig);

/**
 * Initialize a work buffer from the vboot context.
 *
 * This sets the work buffer to the unused portion of the context work buffer.
 *
 * @param ctx		Vboot context
 * @param wb		Work buffer to initialize
 */
void vb2_workbuf_from_ctx(struct vb2_context *ctx, struct vb2_workbuf *wb);

/**
 * Read the GBB header.
 *
 * @param ctx		Vboot context
 * @param gbb		Destination for header
 * @return VB2_SUCCESS, or non-zero if error.
 */
int vb2_read_gbb_header(struct vb2_context *ctx, struct vb2_gbb_header *gbb);

/**
 * Handle vboot failure.
 *
 * If the failure occurred after choosing a firmware slot, and the other
 * firmware slot is not known-bad, try the other firmware slot after reboot.
 *
 * If the failure occurred before choosing a firmware slot, or both slots have
 * failed in successive boots, request recovery.
 *
 * @param reason	Recovery reason
 * @param subcode	Recovery subcode
 */
void vb2_fail(struct vb2_context *ctx, uint8_t reason, uint8_t subcode);

/**
 * Set up the verified boot context data, if not already set up.
 *
 * This uses ctx->workbuf_used=0 as a flag to indicate that the data has not
 * yet been set up.  Caller must set that before calling any voot functions;
 * see 2api.h.
 *
 * @param ctx		Vboot context to initialize
 * @return VB2_SUCCESS, or error code on error.
 */
int vb2_init_context(struct vb2_context *ctx);

/**
 * Check for recovery reasons we can determine early in the boot process.
 *
 * On exit, check ctx->flags for VB2_CONTEXT_RECOVERY_MODE; if present, jump to
 * the recovery path instead of continuing with normal boot.  This is the only
 * direct path to recovery mode.  All other errors later in the boot process
 * should induce a reboot instead of jumping to recovery, so that recovery mode
 * starts from a consistent firmware state.
 *
 * @param ctx		Vboot context
 */
void vb2_check_recovery(struct vb2_context *ctx);

/**
 * Parse the GBB header.
 *
 * @param ctx		Vboot context
 * @return VB2_SUCCESS, or error code on error.
 */
int vb2_fw_parse_gbb(struct vb2_context *ctx);

/**
 * Check developer switch position.
 *
 * @param ctx		Vboot context
 * @return VB2_SUCCESS, or error code on error.
 */
int vb2_check_dev_switch(struct vb2_context *ctx);

/**
 * Check if we need to clear the TPM owner.
 *
 * @param ctx		Vboot context
 * @return VB2_SUCCESS, or error code on error.
 */
int vb2_check_tpm_clear(struct vb2_context *ctx);

/**
 * Decide which firmware slot to try this boot.
 *
 * @param ctx		Vboot context
 * @return VB2_SUCCESS, or error code on error.
 */
int vb2_select_fw_slot(struct vb2_context *ctx);

/**
 * Verify the firmware keyblock using the root key.
 *
 * After this call, the data key is stored in the work buffer.
 *
 * @param ctx		Vboot context
 * @return VB2_SUCCESS, or error code on error.
 */
int vb2_load_fw_keyblock(struct vb2_context *ctx);
int vb21_load_fw_keyblock(struct vb2_context *ctx);

/**
 * Verify the firmware preamble using the data subkey from the keyblock.
 *
 * After this call, the preamble is stored in the work buffer.
 *
 * @param ctx		Vboot context
 * @return VB2_SUCCESS, or error code on error.
 */
int vb2_load_fw_preamble(struct vb2_context *ctx);
int vb21_load_fw_preamble(struct vb2_context *ctx);

/**
 * Verify the kernel keyblock using the previously-loaded kernel key.
 *
 * After this call, the data key is stored in the work buffer.
 *
 * @param ctx		Vboot context
 * @return VB2_SUCCESS, or error code on error.
 */
int vb2_load_kernel_keyblock(struct vb2_context *ctx);

/**
 * Verify the kernel preamble using the data subkey from the keyblock.
 *
 * After this call, the preamble is stored in the work buffer.
 *
 * @param ctx		Vboot context
 * @return VB2_SUCCESS, or error code on error.
 */
int vb2_load_kernel_preamble(struct vb2_context *ctx);