libstb/tpm_chip.c - skiboot - Git at Google

 /* 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.
  */

 #include <skiboot.h>
 #include <device.h>
 #include <string.h>

 #include "status_codes.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, "STB: tpmCmdPcrRead() failed: "
 		      "tpm%d, alg=%x, pcr%d, rc=%d\n",
 		      tpm->id, alg, pcr, rc);
 	} else {
 		prlog(PR_NOTICE,"STB: print pcr-read: tpm%d alg=%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: tpm%d already registered\n",
 			      tpm->id);
 			return STB_ERROR;
 		}
 		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, "TPM: 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, "TPM: 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, "TPM: eventlog init failed: tpm%d rc=%d",
 		      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, "TPM: tpm%d registered: driver=%s felsz=%d\n",
 	      tpm->id, tpm->driver->name, tpm->logmgr.logSize);

 	return 0;

 disable:
 	dt_add_property_string(node, "status", "disabled");
 	prlog(PR_NOTICE, "TPM: tpm node %p disabled\n", node);
 	free(tpm);
 	return STB_ERROR;
 }

 void tpm_init(void)
 {
 	if (!list_empty(&tpm_list)) {
 		/**
 		 * @fwts-label TPMAlreadyInitialized
 		 * @fwts-advice TPM already initialized. Check if tpm is being
 		 * initialized more than once.
 		 */
 		prlog(PR_WARNING, "TPM: tpm device(s) already initialized\n");
 		return;
 	}

 	list_head_init(&tpm_list);

 	/* tpm drivers supported */
 	tpm_i2c_nuvoton_probe();

 	if (list_empty(&tpm_list))
 		/**
 		 * @fwts-label NoTPMRegistered
 		 * @fwts-advice No TPM chip has been initialized. We may not
 		 * have a compatible tpm driver or there is no tpm node in the
 		 * device tree with the expected bindings.
 		 */
 		prlog(PR_ERR, "TPM: no tpm chip registered\n");

 }

 void tpm_cleanup(void)
 {
 	struct tpm_chip *tpm = NULL;

 	tpm = list_pop(&tpm_list, struct tpm_chip, link);

 	while (tpm) {
 		/* deallocate memory */
 		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, "STB: 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, measured, failed;
 	TCG_PCR_EVENT2 event;
 	struct tpm_chip *tpm = NULL;

 	measured = 0;
 	failed = 0;

 	if (list_empty(&tpm_list)) {
 		prlog(PR_NOTICE, "TPM: %s (pcr%d) not measured. No TPM "
 		      "registered/enabled\n", event_msg, pcr);
 		return STB_NO_TPM_INITIALIZED;
 	}

 	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, "TPM: %s -> elog%d FAILED: pcr%d et=%x rc=%d\n",
 			      event_msg, tpm->id, pcr, event_type, rc);
 			tpm_disable(tpm);
 			failed++;
 			continue;
 		}
 #ifdef STB_DEBUG
 		if (rc == 0)
 			prlog(PR_NOTICE, "TPM: %s -> elog%d: pcr%d et=%x "
 			      "ls=%d\n", 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 pcr of 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, "TPM: %s -> tpm%d FAILED: pcr%d rc=%d\n",
 			      event_msg, tpm->id, pcr, rc);
 			tpm_disable(tpm);
 			failed++;
 			continue;
 		}
 #ifdef STB_DEBUG
 		if (rc == 0) {
 			prlog(PR_NOTICE, "TPM: %s -> tpm%d: pcr%d\n",
 			      event_msg, tpm->id, pcr);
 			tpm_print_pcr(tpm, pcr, alg1, size1);
 			tpm_print_pcr(tpm, pcr, alg2, size2);
 		}
 #endif
 		measured++;
 	}

 	prlog(PR_NOTICE, "TPM: %s (pcr%d) measured on %d tpms and "
 	      "failed on %d tpms\n", event_msg, pcr, measured, failed);

 	if (failed > 0)
 		return STB_MEASURE_FAILED;
 	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");
 	}
 }
	/* 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.
	*/

	#include <skiboot.h>
	#include <device.h>
	#include <string.h>

	#include "status_codes.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, "STB: tpmCmdPcrRead() failed: "
	"tpm%d, alg=%x, pcr%d, rc=%d\n",
	tpm->id, alg, pcr, rc);
	} else {
	prlog(PR_NOTICE,"STB: print pcr-read: tpm%d alg=%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: tpm%d already registered\n",
	tpm->id);
	return STB_ERROR;
	}
	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, "TPM: 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, "TPM: 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, "TPM: eventlog init failed: tpm%d rc=%d",
	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, "TPM: tpm%d registered: driver=%s felsz=%d\n",
	tpm->id, tpm->driver->name, tpm->logmgr.logSize);

	return 0;

	disable:
	dt_add_property_string(node, "status", "disabled");
	prlog(PR_NOTICE, "TPM: tpm node %p disabled\n", node);
	free(tpm);
	return STB_ERROR;
	}

	void tpm_init(void)
	{
	if (!list_empty(&tpm_list)) {
	/**
	* @fwts-label TPMAlreadyInitialized
	* @fwts-advice TPM already initialized. Check if tpm is being
	* initialized more than once.
	*/
	prlog(PR_WARNING, "TPM: tpm device(s) already initialized\n");
	return;
	}

	list_head_init(&tpm_list);

	/* tpm drivers supported */
	tpm_i2c_nuvoton_probe();

	if (list_empty(&tpm_list))
	/**
	* @fwts-label NoTPMRegistered
	* @fwts-advice No TPM chip has been initialized. We may not
	* have a compatible tpm driver or there is no tpm node in the
	* device tree with the expected bindings.
	*/
	prlog(PR_ERR, "TPM: no tpm chip registered\n");

	}

	void tpm_cleanup(void)
	{
	struct tpm_chip *tpm = NULL;

	tpm = list_pop(&tpm_list, struct tpm_chip, link);

	while (tpm) {
	/* deallocate memory */
	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, "STB: 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, measured, failed;
	TCG_PCR_EVENT2 event;
	struct tpm_chip *tpm = NULL;

	measured = 0;
	failed = 0;

	if (list_empty(&tpm_list)) {
	prlog(PR_NOTICE, "TPM: %s (pcr%d) not measured. No TPM "
	"registered/enabled\n", event_msg, pcr);
	return STB_NO_TPM_INITIALIZED;
	}

	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, "TPM: %s -> elog%d FAILED: pcr%d et=%x rc=%d\n",
	event_msg, tpm->id, pcr, event_type, rc);
	tpm_disable(tpm);
	failed++;
	continue;
	}
	#ifdef STB_DEBUG
	if (rc == 0)
	prlog(PR_NOTICE, "TPM: %s -> elog%d: pcr%d et=%x "
	"ls=%d\n", 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 pcr of 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, "TPM: %s -> tpm%d FAILED: pcr%d rc=%d\n",
	event_msg, tpm->id, pcr, rc);
	tpm_disable(tpm);
	failed++;
	continue;
	}
	#ifdef STB_DEBUG
	if (rc == 0) {
	prlog(PR_NOTICE, "TPM: %s -> tpm%d: pcr%d\n",
	event_msg, tpm->id, pcr);
	tpm_print_pcr(tpm, pcr, alg1, size1);
	tpm_print_pcr(tpm, pcr, alg2, size2);
	}
	#endif
	measured++;
	}

	prlog(PR_NOTICE, "TPM: %s (pcr%d) measured on %d tpms and "
	"failed on %d tpms\n", event_msg, pcr, measured, failed);

	if (failed > 0)
	return STB_MEASURE_FAILED;
	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");
	}
	}