Commit 5e55a488 authored by Holger Dengler's avatar Holger Dengler Committed by Martin Schwidefsky
Browse files

s390/zcrypt: Separate msgtype implementation from card modules. 



Msgtype implementations are now separated from card specific modules
and can be dynamically registered. Existing msgtype implementations
are restructured in modules.

Signed-off-by: default avatarHolger Dengler <hd@linux.vnet.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent b26bd941

drivers/s390/crypto/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -5,3 +5,4 @@ 
ap-objs := ap_bus.o

obj-$(CONFIG_ZCRYPT) += ap.o zcrypt_api.o zcrypt_pcicc.o zcrypt_pcixcc.o

obj-$(CONFIG_ZCRYPT) += zcrypt_pcica.o zcrypt_cex2a.o

obj-$(CONFIG_ZCRYPT) += zcrypt_msgtype6.o zcrypt_msgtype50.o

drivers/s390/crypto/zcrypt_api.c

+70 −3
Original line number Diff line number Diff line 
/*

 *  zcrypt 2.1.0

 *

 *  Copyright IBM Corp. 2001, 2006

 *  Copyright IBM Corp. 2001, 2012

 *  Author(s): Robert Burroughs

 *	       Eric Rossman (edrossma@us.ibm.com)

 *	       Cornelia Huck <cornelia.huck@de.ibm.com>
@@ -9,6 +9,7 @@ 
 *  Hotplug & misc device support: Jochen Roehrig (roehrig@de.ibm.com)

 *  Major cleanup & driver split: Martin Schwidefsky <schwidefsky@de.ibm.com>

 *				  Ralph Wuerthner <rwuerthn@de.ibm.com>

 *  MSGTYPE restruct:		  Holger Dengler <hd@linux.vnet.ibm.com>

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by
@@ -44,8 +45,8 @@ 
 * Module description.

 */

MODULE_AUTHOR("IBM Corporation");

MODULE_DESCRIPTION("Cryptographic Coprocessor interface, "

		   "Copyright IBM Corp. 2001, 2006");

MODULE_DESCRIPTION("Cryptographic Coprocessor interface, " \

		   "Copyright IBM Corp. 2001, 2012");

MODULE_LICENSE("GPL");



static DEFINE_SPINLOCK(zcrypt_device_lock);
@@ -56,6 +57,9 @@ static atomic_t zcrypt_open_count = ATOMIC_INIT(0); 
static int zcrypt_rng_device_add(void);

static void zcrypt_rng_device_remove(void);



static DEFINE_SPINLOCK(zcrypt_ops_list_lock);

static LIST_HEAD(zcrypt_ops_list);



/*

 * Device attributes common for all crypto devices.

 */
@@ -215,6 +219,8 @@ int zcrypt_device_register(struct zcrypt_device *zdev) 
{

	int rc;



	if (!zdev->ops)

		return -ENODEV;

	rc = sysfs_create_group(&zdev->ap_dev->device.kobj,

				&zcrypt_device_attr_group);

	if (rc)
@@ -269,6 +275,67 @@ void zcrypt_device_unregister(struct zcrypt_device *zdev) 
}

EXPORT_SYMBOL(zcrypt_device_unregister);



void zcrypt_msgtype_register(struct zcrypt_ops *zops)

{

	if (zops->owner) {

		spin_lock_bh(&zcrypt_ops_list_lock);

		list_add_tail(&zops->list, &zcrypt_ops_list);

		spin_unlock_bh(&zcrypt_ops_list_lock);

	}

}

EXPORT_SYMBOL(zcrypt_msgtype_register);



void zcrypt_msgtype_unregister(struct zcrypt_ops *zops)

{

	spin_lock_bh(&zcrypt_ops_list_lock);

	list_del_init(&zops->list);

	spin_unlock_bh(&zcrypt_ops_list_lock);

}

EXPORT_SYMBOL(zcrypt_msgtype_unregister);



static inline

struct zcrypt_ops *__ops_lookup(unsigned char *name, int variant)

{

	struct zcrypt_ops *zops;

	int found = 0;



	spin_lock_bh(&zcrypt_ops_list_lock);

	list_for_each_entry(zops, &zcrypt_ops_list, list) {

		if ((zops->variant == variant) &&

		    (!strncmp(zops->owner->name, name, MODULE_NAME_LEN))) {

			found = 1;

			break;

		}

	}

	spin_unlock_bh(&zcrypt_ops_list_lock);



	if (!found)

		return NULL;

	return zops;

}



struct zcrypt_ops *zcrypt_msgtype_request(unsigned char *name, int variant)

{

	struct zcrypt_ops *zops = NULL;



	zops = __ops_lookup(name, variant);

	if (!zops) {

		request_module(name);

		zops = __ops_lookup(name, variant);

	}

	if ((!zops) || (!try_module_get(zops->owner)))

		return NULL;

	return zops;

}

EXPORT_SYMBOL(zcrypt_msgtype_request);



void zcrypt_msgtype_release(struct zcrypt_ops *zops)

{

	if (zops)

		module_put(zops->owner);

}

EXPORT_SYMBOL(zcrypt_msgtype_release);



/**

 * zcrypt_read (): Not supported beyond zcrypt 1.3.1.

 *

drivers/s390/crypto/zcrypt_api.h

+9 −1
Original line number Diff line number Diff line 
/*

 *  zcrypt 2.1.0

 *

 *  Copyright IBM Corp. 2001, 2006

 *  Copyright IBM Corp. 2001, 2012

 *  Author(s): Robert Burroughs

 *	       Eric Rossman (edrossma@us.ibm.com)

 *	       Cornelia Huck <cornelia.huck@de.ibm.com>
@@ -9,6 +9,7 @@ 
 *  Hotplug & misc device support: Jochen Roehrig (roehrig@de.ibm.com)

 *  Major cleanup & driver split: Martin Schwidefsky <schwidefsky@de.ibm.com>

 *				  Ralph Wuerthner <rwuerthn@de.ibm.com>

 *  MSGTYPE restruct:		  Holger Dengler <hd@linux.vnet.ibm.com>

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by
@@ -87,6 +88,9 @@ struct zcrypt_ops { 
				struct ica_rsa_modexpo_crt *);

	long (*send_cprb)(struct zcrypt_device *, struct ica_xcRB *);

	long (*rng)(struct zcrypt_device *, char *);

	struct list_head list;		/* zcrypt ops list. */

	struct module *owner;

	int variant;

};



struct zcrypt_device {
@@ -116,6 +120,10 @@ void zcrypt_device_get(struct zcrypt_device *); 
int zcrypt_device_put(struct zcrypt_device *);

int zcrypt_device_register(struct zcrypt_device *);

void zcrypt_device_unregister(struct zcrypt_device *);

void zcrypt_msgtype_register(struct zcrypt_ops *);

void zcrypt_msgtype_unregister(struct zcrypt_ops *);

struct zcrypt_ops *zcrypt_msgtype_request(unsigned char *, int);

void zcrypt_msgtype_release(struct zcrypt_ops *);

int zcrypt_api_init(void);

void zcrypt_api_exit(void);

drivers/s390/crypto/zcrypt_cex2a.c

+17 −351
Original line number Diff line number Diff line 
/*

 *  zcrypt 2.1.0

 *

 *  Copyright IBM Corp. 2001, 2006

 *  Copyright IBM Corp. 2001, 2012

 *  Author(s): Robert Burroughs

 *	       Eric Rossman (edrossma@us.ibm.com)

 *

 *  Hotplug & misc device support: Jochen Roehrig (roehrig@de.ibm.com)

 *  Major cleanup & driver split: Martin Schwidefsky <schwidefsky@de.ibm.com>

 *				  Ralph Wuerthner <rwuerthn@de.ibm.com>

 *  MSGTYPE restruct:		  Holger Dengler <hd@linux.vnet.ibm.com>

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by
@@ -35,6 +36,7 @@ 
#include "zcrypt_api.h"

#include "zcrypt_error.h"

#include "zcrypt_cex2a.h"

#include "zcrypt_msgtype50.h"



#define CEX2A_MIN_MOD_SIZE	  1	/*    8 bits	*/

#define CEX2A_MAX_MOD_SIZE	256	/* 2048 bits	*/
@@ -63,14 +65,12 @@ static struct ap_device_id zcrypt_cex2a_ids[] = { 


MODULE_DEVICE_TABLE(ap, zcrypt_cex2a_ids);

MODULE_AUTHOR("IBM Corporation");

MODULE_DESCRIPTION("CEX2A Cryptographic Coprocessor device driver, "

		   "Copyright IBM Corp. 2001, 2006");

MODULE_DESCRIPTION("CEX2A Cryptographic Coprocessor device driver, " \

		   "Copyright IBM Corp. 2001, 2012");

MODULE_LICENSE("GPL");



static int zcrypt_cex2a_probe(struct ap_device *ap_dev);

static void zcrypt_cex2a_remove(struct ap_device *ap_dev);

static void zcrypt_cex2a_receive(struct ap_device *, struct ap_message *,

				 struct ap_message *);



static struct ap_driver zcrypt_cex2a_driver = {

	.probe = zcrypt_cex2a_probe,
@@ -79,344 +79,6 @@ static struct ap_driver zcrypt_cex2a_driver = { 
	.request_timeout = CEX2A_CLEANUP_TIME,

};



/**

 * Convert a ICAMEX message to a type50 MEX message.

 *

 * @zdev: crypto device pointer

 * @zreq: crypto request pointer

 * @mex: pointer to user input data

 *

 * Returns 0 on success or -EFAULT.

 */

static int ICAMEX_msg_to_type50MEX_msg(struct zcrypt_device *zdev,

				       struct ap_message *ap_msg,

				       struct ica_rsa_modexpo *mex)

{

	unsigned char *mod, *exp, *inp;

	int mod_len;



	mod_len = mex->inputdatalength;



	if (mod_len <= 128) {

		struct type50_meb1_msg *meb1 = ap_msg->message;

		memset(meb1, 0, sizeof(*meb1));

		ap_msg->length = sizeof(*meb1);

		meb1->header.msg_type_code = TYPE50_TYPE_CODE;

		meb1->header.msg_len = sizeof(*meb1);

		meb1->keyblock_type = TYPE50_MEB1_FMT;

		mod = meb1->modulus + sizeof(meb1->modulus) - mod_len;

		exp = meb1->exponent + sizeof(meb1->exponent) - mod_len;

		inp = meb1->message + sizeof(meb1->message) - mod_len;

	} else if (mod_len <= 256) {

		struct type50_meb2_msg *meb2 = ap_msg->message;

		memset(meb2, 0, sizeof(*meb2));

		ap_msg->length = sizeof(*meb2);

		meb2->header.msg_type_code = TYPE50_TYPE_CODE;

		meb2->header.msg_len = sizeof(*meb2);

		meb2->keyblock_type = TYPE50_MEB2_FMT;

		mod = meb2->modulus + sizeof(meb2->modulus) - mod_len;

		exp = meb2->exponent + sizeof(meb2->exponent) - mod_len;

		inp = meb2->message + sizeof(meb2->message) - mod_len;

	} else {

		/* mod_len > 256 = 4096 bit RSA Key */

		struct type50_meb3_msg *meb3 = ap_msg->message;

		memset(meb3, 0, sizeof(*meb3));

		ap_msg->length = sizeof(*meb3);

		meb3->header.msg_type_code = TYPE50_TYPE_CODE;

		meb3->header.msg_len = sizeof(*meb3);

		meb3->keyblock_type = TYPE50_MEB3_FMT;

		mod = meb3->modulus + sizeof(meb3->modulus) - mod_len;

		exp = meb3->exponent + sizeof(meb3->exponent) - mod_len;

		inp = meb3->message + sizeof(meb3->message) - mod_len;

	}



	if (copy_from_user(mod, mex->n_modulus, mod_len) ||

	    copy_from_user(exp, mex->b_key, mod_len) ||

	    copy_from_user(inp, mex->inputdata, mod_len))

		return -EFAULT;

	return 0;

}



/**

 * Convert a ICACRT message to a type50 CRT message.

 *

 * @zdev: crypto device pointer

 * @zreq: crypto request pointer

 * @crt: pointer to user input data

 *

 * Returns 0 on success or -EFAULT.

 */

static int ICACRT_msg_to_type50CRT_msg(struct zcrypt_device *zdev,

				       struct ap_message *ap_msg,

				       struct ica_rsa_modexpo_crt *crt)

{

	int mod_len, short_len, long_len, long_offset, limit;

	unsigned char *p, *q, *dp, *dq, *u, *inp;



	mod_len = crt->inputdatalength;

	short_len = mod_len / 2;

	long_len = mod_len / 2 + 8;



	/*

	 * CEX2A cannot handle p, dp, or U > 128 bytes.

	 * If we have one of these, we need to do extra checking.

	 * For CEX3A the limit is 256 bytes.

	 */

	if (zdev->max_mod_size == CEX3A_MAX_MOD_SIZE)

		limit = 256;

	else

		limit = 128;



	if (long_len > limit) {

		/*

		 * zcrypt_rsa_crt already checked for the leading

		 * zeroes of np_prime, bp_key and u_mult_inc.

		 */

		long_offset = long_len - limit;

		long_len = limit;

	} else

		long_offset = 0;



	/*

	 * Instead of doing extra work for p, dp, U > 64 bytes, we'll just use

	 * the larger message structure.

	 */

	if (long_len <= 64) {

		struct type50_crb1_msg *crb1 = ap_msg->message;

		memset(crb1, 0, sizeof(*crb1));

		ap_msg->length = sizeof(*crb1);

		crb1->header.msg_type_code = TYPE50_TYPE_CODE;

		crb1->header.msg_len = sizeof(*crb1);

		crb1->keyblock_type = TYPE50_CRB1_FMT;

		p = crb1->p + sizeof(crb1->p) - long_len;

		q = crb1->q + sizeof(crb1->q) - short_len;

		dp = crb1->dp + sizeof(crb1->dp) - long_len;

		dq = crb1->dq + sizeof(crb1->dq) - short_len;

		u = crb1->u + sizeof(crb1->u) - long_len;

		inp = crb1->message + sizeof(crb1->message) - mod_len;

	} else if (long_len <= 128) {

		struct type50_crb2_msg *crb2 = ap_msg->message;

		memset(crb2, 0, sizeof(*crb2));

		ap_msg->length = sizeof(*crb2);

		crb2->header.msg_type_code = TYPE50_TYPE_CODE;

		crb2->header.msg_len = sizeof(*crb2);

		crb2->keyblock_type = TYPE50_CRB2_FMT;

		p = crb2->p + sizeof(crb2->p) - long_len;

		q = crb2->q + sizeof(crb2->q) - short_len;

		dp = crb2->dp + sizeof(crb2->dp) - long_len;

		dq = crb2->dq + sizeof(crb2->dq) - short_len;

		u = crb2->u + sizeof(crb2->u) - long_len;

		inp = crb2->message + sizeof(crb2->message) - mod_len;

	} else {

		/* long_len >= 256 */

		struct type50_crb3_msg *crb3 = ap_msg->message;

		memset(crb3, 0, sizeof(*crb3));

		ap_msg->length = sizeof(*crb3);

		crb3->header.msg_type_code = TYPE50_TYPE_CODE;

		crb3->header.msg_len = sizeof(*crb3);

		crb3->keyblock_type = TYPE50_CRB3_FMT;

		p = crb3->p + sizeof(crb3->p) - long_len;

		q = crb3->q + sizeof(crb3->q) - short_len;

		dp = crb3->dp + sizeof(crb3->dp) - long_len;

		dq = crb3->dq + sizeof(crb3->dq) - short_len;

		u = crb3->u + sizeof(crb3->u) - long_len;

		inp = crb3->message + sizeof(crb3->message) - mod_len;

	}



	if (copy_from_user(p, crt->np_prime + long_offset, long_len) ||

	    copy_from_user(q, crt->nq_prime, short_len) ||

	    copy_from_user(dp, crt->bp_key + long_offset, long_len) ||

	    copy_from_user(dq, crt->bq_key, short_len) ||

	    copy_from_user(u, crt->u_mult_inv + long_offset, long_len) ||

	    copy_from_user(inp, crt->inputdata, mod_len))

		return -EFAULT;



	return 0;

}



/**

 * Copy results from a type 80 reply message back to user space.

 *

 * @zdev: crypto device pointer

 * @reply: reply AP message.

 * @data: pointer to user output data

 * @length: size of user output data

 *

 * Returns 0 on success or -EFAULT.

 */

static int convert_type80(struct zcrypt_device *zdev,

			  struct ap_message *reply,

			  char __user *outputdata,

			  unsigned int outputdatalength)

{

	struct type80_hdr *t80h = reply->message;

	unsigned char *data;



	if (t80h->len < sizeof(*t80h) + outputdatalength) {

		/* The result is too short, the CEX2A card may not do that.. */

		zdev->online = 0;

		return -EAGAIN;	/* repeat the request on a different device. */

	}

	if (zdev->user_space_type == ZCRYPT_CEX2A)

		BUG_ON(t80h->len > CEX2A_MAX_RESPONSE_SIZE);

	else

		BUG_ON(t80h->len > CEX3A_MAX_RESPONSE_SIZE);

	data = reply->message + t80h->len - outputdatalength;

	if (copy_to_user(outputdata, data, outputdatalength))

		return -EFAULT;

	return 0;

}



static int convert_response(struct zcrypt_device *zdev,

			    struct ap_message *reply,

			    char __user *outputdata,

			    unsigned int outputdatalength)

{

	/* Response type byte is the second byte in the response. */

	switch (((unsigned char *) reply->message)[1]) {

	case TYPE82_RSP_CODE:

	case TYPE88_RSP_CODE:

		return convert_error(zdev, reply);

	case TYPE80_RSP_CODE:

		return convert_type80(zdev, reply,

				      outputdata, outputdatalength);

	default: /* Unknown response type, this should NEVER EVER happen */

		zdev->online = 0;

		return -EAGAIN;	/* repeat the request on a different device. */

	}

}



/**

 * This function is called from the AP bus code after a crypto request

 * "msg" has finished with the reply message "reply".

 * It is called from tasklet context.

 * @ap_dev: pointer to the AP device

 * @msg: pointer to the AP message

 * @reply: pointer to the AP reply message

 */

static void zcrypt_cex2a_receive(struct ap_device *ap_dev,

				 struct ap_message *msg,

				 struct ap_message *reply)

{

	static struct error_hdr error_reply = {

		.type = TYPE82_RSP_CODE,

		.reply_code = REP82_ERROR_MACHINE_FAILURE,

	};

	struct type80_hdr *t80h;

	int length;



	/* Copy the reply message to the request message buffer. */

	if (IS_ERR(reply)) {

		memcpy(msg->message, &error_reply, sizeof(error_reply));

		goto out;

	}

	t80h = reply->message;

	if (t80h->type == TYPE80_RSP_CODE) {

		if (ap_dev->device_type == AP_DEVICE_TYPE_CEX2A)

			length = min(CEX2A_MAX_RESPONSE_SIZE, (int) t80h->len);

		else

			length = min(CEX3A_MAX_RESPONSE_SIZE, (int) t80h->len);

		memcpy(msg->message, reply->message, length);

	} else

		memcpy(msg->message, reply->message, sizeof error_reply);

out:

	complete((struct completion *) msg->private);

}



static atomic_t zcrypt_step = ATOMIC_INIT(0);



/**

 * The request distributor calls this function if it picked the CEX2A

 * device to handle a modexpo request.

 * @zdev: pointer to zcrypt_device structure that identifies the

 *	  CEX2A device to the request distributor

 * @mex: pointer to the modexpo request buffer

 */

static long zcrypt_cex2a_modexpo(struct zcrypt_device *zdev,

				 struct ica_rsa_modexpo *mex)

{

	struct ap_message ap_msg;

	struct completion work;

	int rc;



	ap_init_message(&ap_msg);

	if (zdev->user_space_type == ZCRYPT_CEX2A)

		ap_msg.message = kmalloc(CEX2A_MAX_MESSAGE_SIZE, GFP_KERNEL);

	else

		ap_msg.message = kmalloc(CEX3A_MAX_MESSAGE_SIZE, GFP_KERNEL);

	if (!ap_msg.message)

		return -ENOMEM;

	ap_msg.receive = zcrypt_cex2a_receive;

	ap_msg.psmid = (((unsigned long long) current->pid) << 32) +

				atomic_inc_return(&zcrypt_step);

	ap_msg.private = &work;

	rc = ICAMEX_msg_to_type50MEX_msg(zdev, &ap_msg, mex);

	if (rc)

		goto out_free;

	init_completion(&work);

	ap_queue_message(zdev->ap_dev, &ap_msg);

	rc = wait_for_completion_interruptible(&work);

	if (rc == 0)

		rc = convert_response(zdev, &ap_msg, mex->outputdata,

				      mex->outputdatalength);

	else

		/* Signal pending. */

		ap_cancel_message(zdev->ap_dev, &ap_msg);

out_free:

	kfree(ap_msg.message);

	return rc;

}



/**

 * The request distributor calls this function if it picked the CEX2A

 * device to handle a modexpo_crt request.

 * @zdev: pointer to zcrypt_device structure that identifies the

 *	  CEX2A device to the request distributor

 * @crt: pointer to the modexpoc_crt request buffer

 */

static long zcrypt_cex2a_modexpo_crt(struct zcrypt_device *zdev,

				     struct ica_rsa_modexpo_crt *crt)

{

	struct ap_message ap_msg;

	struct completion work;

	int rc;



	ap_init_message(&ap_msg);

	if (zdev->user_space_type == ZCRYPT_CEX2A)

		ap_msg.message = kmalloc(CEX2A_MAX_MESSAGE_SIZE, GFP_KERNEL);

	else

		ap_msg.message = kmalloc(CEX3A_MAX_MESSAGE_SIZE, GFP_KERNEL);

	if (!ap_msg.message)

		return -ENOMEM;

	ap_msg.receive = zcrypt_cex2a_receive;

	ap_msg.psmid = (((unsigned long long) current->pid) << 32) +

				atomic_inc_return(&zcrypt_step);

	ap_msg.private = &work;

	rc = ICACRT_msg_to_type50CRT_msg(zdev, &ap_msg, crt);

	if (rc)

		goto out_free;

	init_completion(&work);

	ap_queue_message(zdev->ap_dev, &ap_msg);

	rc = wait_for_completion_interruptible(&work);

	if (rc == 0)

		rc = convert_response(zdev, &ap_msg, crt->outputdata,

				      crt->outputdatalength);

	else

		/* Signal pending. */

		ap_cancel_message(zdev->ap_dev, &ap_msg);

out_free:

	kfree(ap_msg.message);

	return rc;

}



/**

 * The crypto operations for a CEX2A card.

 */

static struct zcrypt_ops zcrypt_cex2a_ops = {

	.rsa_modexpo = zcrypt_cex2a_modexpo,

	.rsa_modexpo_crt = zcrypt_cex2a_modexpo_crt,

};



/**

 * Probe function for CEX2A cards. It always accepts the AP device

 * since the bus_match already checked the hardware type.
@@ -458,16 +120,18 @@ static int zcrypt_cex2a_probe(struct ap_device *ap_dev) 
		zdev->speed_rating = CEX3A_SPEED_RATING;

		break;

	}

	if (zdev != NULL) {

	if (!zdev)

		return -ENODEV;

	zdev->ops = zcrypt_msgtype_request(MSGTYPE50_NAME,

					   MSGTYPE50_VARIANT_DEFAULT);

	zdev->ap_dev = ap_dev;

		zdev->ops = &zcrypt_cex2a_ops;

	zdev->online = 1;

	ap_dev->reply = &zdev->reply;

	ap_dev->private = zdev;

	rc = zcrypt_device_register(zdev);

	}

	if (rc) {

		ap_dev->private = NULL;

		zcrypt_msgtype_release(zdev->ops);

		zcrypt_device_free(zdev);

	}

	return rc;
@@ -480,8 +144,10 @@ static int zcrypt_cex2a_probe(struct ap_device *ap_dev) 
static void zcrypt_cex2a_remove(struct ap_device *ap_dev)

{

	struct zcrypt_device *zdev = ap_dev->private;

	struct zcrypt_ops *zops = zdev->ops;



	zcrypt_device_unregister(zdev);

	zcrypt_msgtype_release(zops);

}



int __init zcrypt_cex2a_init(void)

drivers/s390/crypto/zcrypt_msgtype50.c

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