QemuK210/roms/skiboot/libstb/tpm_chip.c

320 lines
8.6 KiB
C

/* Copyright 2013-2016 IBM Corp.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
* implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef pr_fmt
#define pr_fmt(fmt) "STB: " fmt
#endif
#include <skiboot.h>
#include <device.h>
#include <string.h>
#include "container.h"
#include "tpm_chip.h"
#include "drivers/tpm_i2c_nuvoton.h"
#include "tss/trustedbootCmds.H"
/* For debugging only */
//#define STB_DEBUG
static struct list_head tpm_list = LIST_HEAD_INIT(tpm_list);
#ifdef STB_DEBUG
static void tpm_print_pcr(struct tpm_chip *tpm, TPM_Pcr pcr, TPM_Alg_Id alg,
size_t size)
{
int rc;
uint8_t digest[TPM_ALG_SHA256_SIZE];
memset(digest, 0, size);
rc = tpmCmdPcrRead(tpm, pcr, alg, digest, size);
if (rc) {
/**
* @fwts-label STBPCRReadFailed
* @fwts-advice STB_DEBUG should not be enabled
* in production. PCR read operation failed.
* This TSS implementation is part of hostboot,
* but the source code is shared with skiboot.
* 1) The hostboot TSS may have been updated.
* 2) This may be caused by the short I2C
* timeout and can be fixed by increasing the
* timeout. Otherwise this indicates a bug in
* the TSS or the TPM device driver. Each one
* has local debug macros that can help.
*/
prlog(PR_ERR, "tpmCmdPcrRead() failed: "
"tpm%d, alg=%x, pcr%d, rc=%d\n",
tpm->id, alg, pcr, rc);
} else {
prlog(PR_NOTICE,"print pcr-read: tpm%d alg=0x%x pcr%d\n",
tpm->id, alg, pcr);
stb_print_data(digest, size);
}
}
#endif
int tpm_register_chip(struct dt_node *node, struct tpm_dev *dev,
struct tpm_driver *driver)
{
int i, rc;
uint64_t sml_base;
uint32_t sml_size;
struct tpm_chip *tpm;
i = 0;
list_for_each(&tpm_list, tpm, link) {
if (tpm->node == node) {
/**
* @fwts-label TPMAlreadyRegistered
* @fwts-advice TPM node already registered. The same
* node is being registered twice or there is a
* tpm node duplicate in the device tree
*/
prlog(PR_WARNING, "tpm%d already registered\n", tpm->id);
return -1;
}
i++;
}
tpm = (struct tpm_chip*) malloc(sizeof(struct tpm_chip));
assert(tpm);
tpm->id = i;
/*
* Read event log info from the tpm device tree node. Both
* linux,sml-base and linux,sml-size properties are documented in
* 'doc/device-tree/tpm.rst'
*/
sml_base = dt_prop_get_u64_def(node, "linux,sml-base", 0);
/* Check if sml-base is really 0 or it just doesn't exist */
if (!sml_base &&
!dt_find_property(node, "linux,sml-base")) {
/**
* @fwts-label TPMSmlBaseNotFound
* @fwts-advice linux,sml-base property not found. This
* indicates a Hostboot bug if the property really
* doesn't exist in the tpm node.
*/
prlog(PR_ERR, "linux,sml-base property not found "
"tpm node %p\n", node);
goto disable;
}
sml_size = dt_prop_get_u32_def(node, "linux,sml-size", 0);
if (!sml_size) {
/**
* @fwts-label TPMSmlSizeNotFound
* @fwts-advice linux,sml-size property not found. This
* indicates a Hostboot bug if the property really
* doesn't exist in the tpm node.
*/
prlog(PR_ERR, "linux,sml-size property not found, "
"tpm node %p\n", node);
goto disable;
}
/*
* Initialize the event log manager by walking through the log to identify
* what is the next free position in the log
*/
rc = TpmLogMgr_initializeUsingExistingLog(&tpm->logmgr,
(uint8_t*) sml_base, sml_size);
if (rc) {
/**
* @fwts-label TPMInitEventLogFailed
* @fwts-advice Hostboot creates and adds entries to the
* event log. The failed init function is part of hostboot,
* but the source code is shared with skiboot. If the hostboot
* TpmLogMgr code (or friends) has been updated, the changes
* need to be applied to skiboot as well.
*/
prlog(PR_ERR, "eventlog init failed: tpm%d rc=%d\n",
tpm->id, rc);
goto disable;
}
tpm->enabled = true;
tpm->node = node;
tpm->dev = dev;
tpm->driver = driver;
list_add_tail(&tpm_list, &tpm->link);
prlog(PR_NOTICE, "Found tpm%d,%s evLogLen=%d evLogSize=%d\n",
tpm->id, tpm->driver->name, tpm->logmgr.logSize,
tpm->logmgr.logMaxSize);
return 0;
disable:
dt_add_property_string(node, "status", "disabled");
prlog(PR_NOTICE, "tpm node %p disabled\n", node);
free(tpm);
return -1;
}
int tpm_init(void)
{
if (!list_empty(&tpm_list))
return 0;
list_head_init(&tpm_list);
/* tpm drivers supported */
tpm_i2c_nuvoton_probe();
if (list_empty(&tpm_list)) {
prlog(PR_INFO, "no compatible tpm device found!\n");
return -1;
}
return 0;
}
void tpm_cleanup(void)
{
struct tpm_chip *tpm = NULL;
tpm = list_pop(&tpm_list, struct tpm_chip, link);
while (tpm) {
if (tpm->dev)
free(tpm->dev);
tpm->driver = NULL;
free(tpm);
tpm = list_pop(&tpm_list, struct tpm_chip, link);
}
list_head_init(&tpm_list);
}
static void tpm_disable(struct tpm_chip *tpm)
{
assert(tpm);
tpm->enabled = false;
prlog(PR_NOTICE, "tpm%d disabled\n", tpm->id);
}
int tpm_extendl(TPM_Pcr pcr,
TPM_Alg_Id alg1, uint8_t* digest1, size_t size1,
TPM_Alg_Id alg2, uint8_t* digest2, size_t size2,
uint32_t event_type, const char* event_msg)
{
int rc, failed;
TCG_PCR_EVENT2 event;
struct tpm_chip *tpm = NULL;
failed = 0;
if (list_empty(&tpm_list)) {
prlog(PR_ERR, "%s (pcr%d) NOT MEASURED. No TPM "
"registered/enabled\n",
(event_type==EV_SEPARATOR) ? "EV_SEPARATOR" : event_msg,
pcr);
return -1;
}
list_for_each(&tpm_list, tpm, link) {
if (!tpm->enabled)
continue;
event = TpmLogMgr_genLogEventPcrExtend(pcr, alg1, digest1, size1,
alg2, digest2, size2,
event_type, event_msg);
/* eventlog recording */
rc = TpmLogMgr_addEvent(&tpm->logmgr, &event);
if (rc) {
/**
* @fwts-label STBAddEventFailed
* @fwts-advice TpmLogMgr failed to add a new event
* to the event log. TpmLogMgr is part of hostboot,
* but the source code is shared with skiboot.
* 1) The hostboot TpmLogMgr code may have
* been updated.
* 2) Check that max event log size was not reached
* and log marshall executed with no error. Enabling the
* trace routines in trustedbootUtils.H may help.
*/
prlog(PR_ERR, "%s -> evLog%d FAILED: pcr%d evType=0x%x rc=%d\n",
(event_type==EV_SEPARATOR) ? "EV_SEPARATOR" : event_msg,
tpm->id, pcr, event_type, rc);
tpm_disable(tpm);
failed++;
continue;
}
#ifdef STB_DEBUG
if (rc == 0)
prlog(PR_NOTICE, "%s -> evLog%d: pcr%d evType=0x%x "
"evLogLen=%d\n",
(event_type==EV_SEPARATOR) ? "EV_SEPARATOR" : event_msg,
tpm->id, pcr, event_type, tpm->logmgr.logSize);
tpm_print_pcr(tpm, pcr, alg1, size1);
tpm_print_pcr(tpm, pcr, alg2, size2);
#endif
/* extend the pcr number in both sha1 and sha256 banks*/
rc = tpmCmdPcrExtend2Hash(tpm, pcr,
alg1, digest1, size1,
alg2, digest2, size2);
if (rc) {
/**
* @fwts-label STBPCRExtendFailed
* @fwts-advice PCR extend operation failed. This TSS
* implementation is part of hostboot, but the source
* code is shared with skiboot.
* 1) The hostboot TSS may have been updated.
* 2) This may be caused by the short I2C timeout and
* can be fixed by increasing the timeout. Otherwise,
* this indicates a bug in the TSS or the TPM
* device driver. Each one has local debug macros that
* can help.
*/
prlog(PR_ERR, "%s -> tpm%d FAILED: pcr%d rc=%d\n",
(event_type==EV_SEPARATOR) ? "EV_SEPARATOR" : event_msg,
tpm->id, pcr, rc);
tpm_disable(tpm);
failed++;
continue;
}
#ifdef STB_DEBUG
if (rc == 0) {
prlog(PR_NOTICE, "%s -> tpm%d: pcr%d\n",
(event_type==EV_SEPARATOR) ? "EV_SEPARATOR" : event_msg,
tpm->id, pcr);
tpm_print_pcr(tpm, pcr, alg1, size1);
tpm_print_pcr(tpm, pcr, alg2, size2);
}
#endif
prlog(PR_NOTICE, "%s measured on pcr%d (tpm%d, evType 0x%x, "
"evLogLen %d)\n",
(event_type==EV_SEPARATOR) ? "EV_SEPARATOR" : event_msg,
pcr, tpm->id, event_type, tpm->logmgr.logSize);
}
if (failed > 0)
return -2;
return 0;
}
void tpm_add_status_property(void) {
struct tpm_chip *tpm;
list_for_each(&tpm_list, tpm, link) {
dt_add_property_string(tpm->node, "status",
tpm->enabled ? "okay" : "disabled");
}
}