1181624Skmacy/****************************************************************************** 2181624Skmacy * tpmif.h 3181624Skmacy * 4181624Skmacy * TPM I/O interface for Xen guest OSes. 5181624Skmacy * 6181624Skmacy * Permission is hereby granted, free of charge, to any person obtaining a copy 7181624Skmacy * of this software and associated documentation files (the "Software"), to 8181624Skmacy * deal in the Software without restriction, including without limitation the 9181624Skmacy * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or 10181624Skmacy * sell copies of the Software, and to permit persons to whom the Software is 11181624Skmacy * furnished to do so, subject to the following conditions: 12181624Skmacy * 13181624Skmacy * The above copyright notice and this permission notice shall be included in 14181624Skmacy * all copies or substantial portions of the Software. 15181624Skmacy * 16181624Skmacy * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17181624Skmacy * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18181624Skmacy * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 19181624Skmacy * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 20181624Skmacy * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 21181624Skmacy * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 22181624Skmacy * DEALINGS IN THE SOFTWARE. 23181624Skmacy * 24181624Skmacy * Copyright (c) 2005, IBM Corporation 25181624Skmacy * 26181624Skmacy * Author: Stefan Berger, stefanb@us.ibm.com 27181624Skmacy * Grant table support: Mahadevan Gomathisankaran 28181624Skmacy * 29181624Skmacy * This code has been derived from tools/libxc/xen/io/netif.h 30181624Skmacy * 31181624Skmacy * Copyright (c) 2003-2004, Keir Fraser 32181624Skmacy */ 33181624Skmacy 34181624Skmacy#ifndef __XEN_PUBLIC_IO_TPMIF_H__ 35181624Skmacy#define __XEN_PUBLIC_IO_TPMIF_H__ 36181624Skmacy 37181624Skmacy#include "../grant_table.h" 38181624Skmacy 39181624Skmacystruct tpmif_tx_request { 40181624Skmacy unsigned long addr; /* Machine address of packet. */ 41181624Skmacy grant_ref_t ref; /* grant table access reference */ 42181624Skmacy uint16_t unused; 43181624Skmacy uint16_t size; /* Packet size in bytes. */ 44181624Skmacy}; 45181624Skmacytypedef struct tpmif_tx_request tpmif_tx_request_t; 46181624Skmacy 47181624Skmacy/* 48181624Skmacy * The TPMIF_TX_RING_SIZE defines the number of pages the 49181624Skmacy * front-end and backend can exchange (= size of array). 50181624Skmacy */ 51181624Skmacytypedef uint32_t TPMIF_RING_IDX; 52181624Skmacy 53181624Skmacy#define TPMIF_TX_RING_SIZE 1 54181624Skmacy 55181624Skmacy/* This structure must fit in a memory page. */ 56181624Skmacy 57181624Skmacystruct tpmif_ring { 58181624Skmacy struct tpmif_tx_request req; 59181624Skmacy}; 60181624Skmacytypedef struct tpmif_ring tpmif_ring_t; 61181624Skmacy 62181624Skmacystruct tpmif_tx_interface { 63181624Skmacy struct tpmif_ring ring[TPMIF_TX_RING_SIZE]; 64181624Skmacy}; 65181624Skmacytypedef struct tpmif_tx_interface tpmif_tx_interface_t; 66181624Skmacy 67288917Sroyger/****************************************************************************** 68288917Sroyger * TPM I/O interface for Xen guest OSes, v2 69288917Sroyger * 70288917Sroyger * Author: Daniel De Graaf <dgdegra@tycho.nsa.gov> 71288917Sroyger * 72288917Sroyger * This protocol emulates the request/response behavior of a TPM using a Xen 73288917Sroyger * shared memory interface. All interaction with the TPM is at the direction 74288917Sroyger * of the frontend, since a TPM (hardware or virtual) is a passive device - 75288917Sroyger * the backend only processes commands as requested by the frontend. 76288917Sroyger * 77288917Sroyger * The frontend sends a request to the TPM by populating the shared page with 78288917Sroyger * the request packet, changing the state to TPMIF_STATE_SUBMIT, and sending 79288917Sroyger * and event channel notification. When the backend is finished, it will set 80288917Sroyger * the state to TPMIF_STATE_FINISH and send an event channel notification. 81288917Sroyger * 82288917Sroyger * In order to allow long-running commands to be canceled, the frontend can 83288917Sroyger * at any time change the state to TPMIF_STATE_CANCEL and send a notification. 84288917Sroyger * The TPM can either finish the command (changing state to TPMIF_STATE_FINISH) 85288917Sroyger * or can cancel the command and change the state to TPMIF_STATE_IDLE. The TPM 86288917Sroyger * can also change the state to TPMIF_STATE_IDLE instead of TPMIF_STATE_FINISH 87288917Sroyger * if another reason for cancellation is required - for example, a physical 88288917Sroyger * TPM may cancel a command if the interface is seized by another locality. 89288917Sroyger * 90288917Sroyger * The TPM command format is defined by the TCG, and is available at 91288917Sroyger * http://www.trustedcomputinggroup.org/resources/tpm_main_specification 92288917Sroyger */ 93288917Sroyger 94288917Sroygerenum tpmif_state { 95288917Sroyger TPMIF_STATE_IDLE, /* no contents / vTPM idle / cancel complete */ 96288917Sroyger TPMIF_STATE_SUBMIT, /* request ready / vTPM working */ 97288917Sroyger TPMIF_STATE_FINISH, /* response ready / vTPM idle */ 98288917Sroyger TPMIF_STATE_CANCEL, /* cancel requested / vTPM working */ 99288917Sroyger}; 100288917Sroyger/* Note: The backend should only change state to IDLE or FINISH, while the 101288917Sroyger * frontend should only change to SUBMIT or CANCEL. Status changes do not need 102288917Sroyger * to use atomic operations. 103288917Sroyger */ 104288917Sroyger 105288917Sroyger 106288917Sroyger/* The shared page for vTPM request/response packets looks like: 107288917Sroyger * 108288917Sroyger * Offset Contents 109288917Sroyger * ================================================= 110288917Sroyger * 0 struct tpmif_shared_page 111288917Sroyger * 16 [optional] List of grant IDs 112288917Sroyger * 16+4*nr_extra_pages TPM packet data 113288917Sroyger * 114288917Sroyger * If the TPM packet data extends beyond the end of a single page, the grant IDs 115288917Sroyger * defined in extra_pages are used as if they were mapped immediately following 116288917Sroyger * the primary shared page. The grants are allocated by the frontend and mapped 117288917Sroyger * by the backend. Before sending a request spanning multiple pages, the 118288917Sroyger * frontend should verify that the TPM supports such large requests by querying 119288917Sroyger * the TPM_CAP_PROP_INPUT_BUFFER property from the TPM. 120288917Sroyger */ 121288917Sroygerstruct tpmif_shared_page { 122288917Sroyger uint32_t length; /* request/response length in bytes */ 123288917Sroyger 124288917Sroyger uint8_t state; /* enum tpmif_state */ 125288917Sroyger uint8_t locality; /* for the current request */ 126288917Sroyger uint8_t pad; /* should be zero */ 127288917Sroyger 128288917Sroyger uint8_t nr_extra_pages; /* extra pages for long packets; may be zero */ 129288917Sroyger uint32_t extra_pages[0]; /* grant IDs; length is actually nr_extra_pages */ 130288917Sroyger}; 131288917Sroygertypedef struct tpmif_shared_page tpmif_shared_page_t; 132288917Sroyger 133181624Skmacy#endif 134181624Skmacy 135181624Skmacy/* 136181624Skmacy * Local variables: 137181624Skmacy * mode: C 138288917Sroyger * c-file-style: "BSD" 139181624Skmacy * c-basic-offset: 4 140181624Skmacy * tab-width: 4 141181624Skmacy * indent-tabs-mode: nil 142181624Skmacy * End: 143181624Skmacy */ 144