text: // SPDX-License-Identifier: GPL-2.0+
  /*
   *  Copyright IBM Corp. 2001, 2018
   *  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>
   */
  
  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/err.h>
  #include <linux/delay.h>
  #include <linux/slab.h>
  #include <linux/atomic.h>
  #include <linux/uaccess.h>
  #include <linux/mod_devicetable.h>
  
  #include "ap_bus.h"
  #include "zcrypt_api.h"
  #include "zcrypt_error.h"
  #include "zcrypt_msgtype6.h"
  #include "zcrypt_cex2c.h"
  #include "zcrypt_cca_key.h"
  
  #define CEX2C_MIN_MOD_SIZE	 16	/*  128 bits	*/
  #define CEX2C_MAX_MOD_SIZE	256	/* 2048 bits	*/
  #define CEX3C_MIN_MOD_SIZE	 16	/*  128 bits	*/
  #define CEX3C_MAX_MOD_SIZE	512	/* 4096 bits	*/
  #define CEX2C_MAX_XCRB_MESSAGE_SIZE (12*1024)
  #define CEX2C_CLEANUP_TIME	(15*HZ)
  
  MODULE_AUTHOR("IBM Corporation");
  MODULE_DESCRIPTION("CEX2C/CEX3C Cryptographic Coprocessor device driver, " \
  		   "Copyright IBM Corp. 2001, 2018");
  MODULE_LICENSE("GPL");
  
  static struct ap_device_id zcrypt_cex2c_card_ids[] = {
  	{ .dev_type = AP_DEVICE_TYPE_CEX2C,
  	  .match_flags = AP_DEVICE_ID_MATCH_CARD_TYPE },
  	{ .dev_type = AP_DEVICE_TYPE_CEX3C,
  	  .match_flags = AP_DEVICE_ID_MATCH_CARD_TYPE },
  	{ /* end of list */ },
  };
  
  MODULE_DEVICE_TABLE(ap, zcrypt_cex2c_card_ids);
  
  static struct ap_device_id zcrypt_cex2c_queue_ids[] = {
  	{ .dev_type = AP_DEVICE_TYPE_CEX2C,
  	  .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
  	{ .dev_type = AP_DEVICE_TYPE_CEX3C,
  	  .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
  	{ /* end of list */ },
  };
  
  MODULE_DEVICE_TABLE(ap, zcrypt_cex2c_queue_ids);
  
  /**
   * Large random number detection function. Its sends a message to a CEX2C/CEX3C
   * card to find out if large random numbers are supported.
   * @ap_dev: pointer to the AP device.
   *
   * Returns 1 if large random numbers are supported, 0 if not and < 0 on error.
   */
  static int zcrypt_cex2c_rng_supported(struct ap_queue *aq)
  {
  	struct ap_message ap_msg;
  	unsigned long long psmid;
  	unsigned int domain;
  	struct {
  		struct type86_hdr hdr;
  		struct type86_fmt2_ext fmt2;
  		struct CPRBX cprbx;
  	} __packed *reply;
  	struct {
  		struct type6_hdr hdr;
  		struct CPRBX cprbx;
  		char function_code[2];
  		short int rule_length;
  		char rule[8];
  		short int verb_length;
  		short int key_length;
  	} __packed *msg;
  	int rc, i;
  
  	ap_init_message(&ap_msg);
  	ap_msg.message = (void *) get_zeroed_page(GFP_KERNEL);
  	if (!ap_msg.message)
  		return -ENOMEM;
  
  	rng_type6CPRB_msgX(&ap_msg, 4, &domain);
  
  	msg = ap_msg.message;
  	msg->cprbx.domain = AP_QID_QUEUE(aq->qid);
  
  	rc = ap_send(aq->qid, 0x0102030405060708ULL, ap_msg.message,
  		     ap_msg.length);
  	if (rc)
  		goto out_free;
  
  	/* Wait for the test message to complete. */
  	for (i = 0; i < 2 * HZ; i++) {
  		msleep(1000 / HZ);
  		rc = ap_recv(aq->qid, &psmid, ap_msg.message, 4096);
  		if (rc == 0 && psmid == 0x0102030405060708ULL)
  			break;
  	}
  
  	if (i >= 2 * HZ) {
  		/* Got no answer. */
  		rc = -ENODEV;
  		goto out_free;
  	}
  
  	reply = ap_msg.message;
  	if (reply->cprbx.ccp_rtcode == 0 && reply->cprbx.ccp_rscode == 0)
  		rc = 1;
  	else
  		rc = 0;
  out_free:
  	free_page((unsigned long) ap_msg.message);
  	return rc;
  }
  
  /**
   * Probe function for CEX2C/CEX3C card devices. It always accepts the
   * AP device since the bus_match already checked the hardware type.
   * @ap_dev: pointer to the AP card device.
   */
  static int zcrypt_cex2c_card_probe(struct ap_device *ap_dev)
  {
  	/*
  	 * Normalized speed ratings per crypto adapter
  	 * MEX_1k, MEX_2k, MEX_4k, CRT_1k, CRT_2k, CRT_4k, RNG, SECKEY
  	 */
  	static const int CEX2C_SPEED_IDX[] = {
  		1000, 1400, 2400, 1100, 1500, 2600, 100, 12};
  	static const int CEX3C_SPEED_IDX[] = {
  		500,  700, 1400,  550,	800, 1500,  80, 10};
  
  	struct ap_card *ac = to_ap_card(&ap_dev->device);
  	struct zcrypt_card *zc;
  	int rc = 0;
  
  	zc = zcrypt_card_alloc();
  	if (!zc)
  		return -ENOMEM;
  	zc->card = ac;
  	ac->private = zc;
  	switch (ac->ap_dev.device_type) {
  	case AP_DEVICE_TYPE_CEX2C:
  		zc->user_space_type = ZCRYPT_CEX2C;
  		zc->type_string = "CEX2C";
  		memcpy(zc->speed_rating, CEX2C_SPEED_IDX,
  		       sizeof(CEX2C_SPEED_IDX));
  		zc->min_mod_size = CEX2C_MIN_MOD_SIZE;
  		zc->max_mod_size = CEX2C_MAX_MOD_SIZE;
  		zc->max_exp_bit_length = CEX2C_MAX_MOD_SIZE;
  		break;
  	case AP_DEVICE_TYPE_CEX3C:
  		zc->user_space_type = ZCRYPT_CEX3C;
  		zc->type_string = "CEX3C";
  		memcpy(zc->speed_rating, CEX3C_SPEED_IDX,
  		       sizeof(CEX3C_SPEED_IDX));
  		zc->min_mod_size = CEX3C_MIN_MOD_SIZE;
  		zc->max_mod_size = CEX3C_MAX_MOD_SIZE;
  		zc->max_exp_bit_length = CEX3C_MAX_MOD_SIZE;
  		break;
  	default:
  		zcrypt_card_free(zc);
  		return -ENODEV;
  	}
  	zc->online = 1;
  
  	rc = zcrypt_card_register(zc);
  	if (rc) {
  		ac->private = NULL;
  		zcrypt_card_free(zc);
  	}
  
  	return rc;
  }
  
  /**
   * This is called to remove the CEX2C/CEX3C card driver information
   * if an AP card device is removed.
   */
  static void zcrypt_cex2c_card_remove(struct ap_device *ap_dev)
  {
  	struct zcrypt_card *zc = to_ap_card(&ap_dev->device)->private;
  
  	if (zc)
  		zcrypt_card_unregister(zc);
  }
  
  static struct ap_driver zcrypt_cex2c_card_driver = {
  	.probe = zcrypt_cex2c_card_probe,
  	.remove = zcrypt_cex2c_card_remove,
  	.ids = zcrypt_cex2c_card_ids,
  	.flags = AP_DRIVER_FLAG_DEFAULT,
  };
  
  /**
   * Probe function for CEX2C/CEX3C queue devices. It always accepts the
   * AP device since the bus_match already checked the hardware type.
   * @ap_dev: pointer to the AP card device.
   */
  static int zcrypt_cex2c_queue_probe(struct ap_device *ap_dev)
  {
  	struct ap_queue *aq = to_ap_queue(&ap_dev->device);
  	struct zcrypt_queue *zq;
  	int rc;
  
  	zq = zcrypt_queue_alloc(CEX2C_MAX_XCRB_MESSAGE_SIZE);
  	if (!zq)
  		return -ENOMEM;
  	zq->queue = aq;
  	zq->online = 1;
  	atomic_set(&zq->load, 0);
  	rc = zcrypt_cex2c_rng_supported(aq);
  	if (rc < 0) {
  		zcrypt_queue_free(zq);
  		return rc;
  	}
  	if (rc)
  		zq->ops = zcrypt_msgtype(MSGTYPE06_NAME,
  					 MSGTYPE06_VARIANT_DEFAULT);
  	else
  		zq->ops = zcrypt_msgtype(MSGTYPE06_NAME,
  					 MSGTYPE06_VARIANT_NORNG);
  	ap_queue_init_reply(aq, &zq->reply);
  	aq->request_timeout = CEX2C_CLEANUP_TIME;
  	aq->private = zq;
  	rc = zcrypt_queue_register(zq);
  	if (rc) {
  		aq->private = NULL;
  		zcrypt_queue_free(zq);
  	}
  	return rc;
  }
  
  /**
   * This is called to remove the CEX2C/CEX3C queue driver information
   * if an AP queue device is removed.
   */
  static void zcrypt_cex2c_queue_remove(struct ap_device *ap_dev)
  {
  	struct ap_queue *aq = to_ap_queue(&ap_dev->device);
  	struct zcrypt_queue *zq = aq->private;
  
  	if (zq)
  		zcrypt_queue_unregister(zq);
  }
  
  static struct ap_driver zcrypt_cex2c_queue_driver = {
  	.probe = zcrypt_cex2c_queue_probe,
  	.remove = zcrypt_cex2c_queue_remove,
  	.suspend = ap_queue_suspend,
  	.resume = ap_queue_resume,
  	.ids = zcrypt_cex2c_queue_ids,
  	.flags = AP_DRIVER_FLAG_DEFAULT,
  };
  
  int __init zcrypt_cex2c_init(void)
  {
  	int rc;
  
  	rc = ap_driver_register(&zcrypt_cex2c_card_driver,
  				THIS_MODULE, "cex2card");
  	if (rc)
  		return rc;
  
  	rc = ap_driver_register(&zcrypt_cex2c_queue_driver,
  				THIS_MODULE, "cex2cqueue");
  	if (rc)
  		ap_driver_unregister(&zcrypt_cex2c_card_driver);
  
  	return rc;
  }
  
  void zcrypt_cex2c_exit(void)
  {
  	ap_driver_unregister(&zcrypt_cex2c_queue_driver);
  	ap_driver_unregister(&zcrypt_cex2c_card_driver);
  }
  
  module_init(zcrypt_cex2c_init);
  module_exit(zcrypt_cex2c_exit);
  