linux-stable/drivers/s390/crypto/zcrypt_cex2c.c
Harald Freudenberger 91ffc519c1 s390/zcrypt: introduce msg tracking in zcrypt functions
Introduce a new internal struct zcrypt_track with an retry counter
field and a last return code field. Fill and update these fields at
certain points during processing of an request/reply. This tracking
info is then used to
- avoid trying to resend the message forever. Now each message is
  tried to be send TRACK_AGAIN_MAX (currently 10) times and then the
  ioctl returns to userspace with errno EAGAIN.
- avoid trying to resend the message on the very same card/domain. If
  possible (more than one APQN with same quality) don't use the very
  same qid as the previous attempt when again scheduling the request.
  This is done by adding penalty weight values when the dispatching
  takes place. There is a penalty TRACK_AGAIN_CARD_WEIGHT_PENALTY for
  using the same card as previously and another penalty define
  TRACK_AGAIN_QUEUE_WEIGHT_PENALTY to be considered when the same qid
  as the previous sent attempt is calculated. Both values make it
  harder to choose the very same card/domain but not impossible. For
  example when only one APQN is available a resend can only address the
  very same APQN.

There are some more ideas for the future to extend the use of this
tracking information. For example the last response code at NQAP and
DQAP could be stored there, giving the possibility to extended tracing
and debugging about requests failing to get processed properly.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-10-07 21:49:59 +02:00

429 lines
11 KiB
C

// 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"
#include "zcrypt_ccamisc.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);
/*
* CCA card additional device attributes
*/
static ssize_t cca_serialnr_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct cca_info ci;
struct ap_card *ac = to_ap_card(dev);
struct zcrypt_card *zc = ac->private;
memset(&ci, 0, sizeof(ci));
if (ap_domain_index >= 0)
cca_get_info(ac->id, ap_domain_index, &ci, zc->online);
return scnprintf(buf, PAGE_SIZE, "%s\n", ci.serial);
}
static struct device_attribute dev_attr_cca_serialnr =
__ATTR(serialnr, 0444, cca_serialnr_show, NULL);
static struct attribute *cca_card_attrs[] = {
&dev_attr_cca_serialnr.attr,
NULL,
};
static const struct attribute_group cca_card_attr_grp = {
.attrs = cca_card_attrs,
};
/*
* CCA queue additional device attributes
*/
static ssize_t cca_mkvps_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
int n = 0;
struct cca_info ci;
struct zcrypt_queue *zq = to_ap_queue(dev)->private;
static const char * const cao_state[] = { "invalid", "valid" };
static const char * const new_state[] = { "empty", "partial", "full" };
memset(&ci, 0, sizeof(ci));
cca_get_info(AP_QID_CARD(zq->queue->qid),
AP_QID_QUEUE(zq->queue->qid),
&ci, zq->online);
if (ci.new_aes_mk_state >= '1' && ci.new_aes_mk_state <= '3')
n = scnprintf(buf, PAGE_SIZE, "AES NEW: %s 0x%016llx\n",
new_state[ci.new_aes_mk_state - '1'],
ci.new_aes_mkvp);
else
n = scnprintf(buf, PAGE_SIZE, "AES NEW: - -\n");
if (ci.cur_aes_mk_state >= '1' && ci.cur_aes_mk_state <= '2')
n += scnprintf(buf + n, PAGE_SIZE - n,
"AES CUR: %s 0x%016llx\n",
cao_state[ci.cur_aes_mk_state - '1'],
ci.cur_aes_mkvp);
else
n += scnprintf(buf + n, PAGE_SIZE - n, "AES CUR: - -\n");
if (ci.old_aes_mk_state >= '1' && ci.old_aes_mk_state <= '2')
n += scnprintf(buf + n, PAGE_SIZE - n,
"AES OLD: %s 0x%016llx\n",
cao_state[ci.old_aes_mk_state - '1'],
ci.old_aes_mkvp);
else
n += scnprintf(buf + n, PAGE_SIZE - n, "AES OLD: - -\n");
if (ci.new_apka_mk_state >= '1' && ci.new_apka_mk_state <= '3')
n += scnprintf(buf + n, PAGE_SIZE - n,
"APKA NEW: %s 0x%016llx\n",
new_state[ci.new_apka_mk_state - '1'],
ci.new_apka_mkvp);
else
n += scnprintf(buf + n, PAGE_SIZE - n, "APKA NEW: - -\n");
if (ci.cur_apka_mk_state >= '1' && ci.cur_apka_mk_state <= '2')
n += scnprintf(buf + n, PAGE_SIZE - n,
"APKA CUR: %s 0x%016llx\n",
cao_state[ci.cur_apka_mk_state - '1'],
ci.cur_apka_mkvp);
else
n += scnprintf(buf + n, PAGE_SIZE - n, "APKA CUR: - -\n");
if (ci.old_apka_mk_state >= '1' && ci.old_apka_mk_state <= '2')
n += scnprintf(buf + n, PAGE_SIZE - n,
"APKA OLD: %s 0x%016llx\n",
cao_state[ci.old_apka_mk_state - '1'],
ci.old_apka_mkvp);
else
n += scnprintf(buf + n, PAGE_SIZE - n, "APKA OLD: - -\n");
return n;
}
static struct device_attribute dev_attr_cca_mkvps =
__ATTR(mkvps, 0444, cca_mkvps_show, NULL);
static struct attribute *cca_queue_attrs[] = {
&dev_attr_cca_mkvps.attr,
NULL,
};
static const struct attribute_group cca_queue_attr_grp = {
.attrs = cca_queue_attrs,
};
/**
* 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.msg = (void *) get_zeroed_page(GFP_KERNEL);
if (!ap_msg.msg)
return -ENOMEM;
rng_type6CPRB_msgX(&ap_msg, 4, &domain);
msg = ap_msg.msg;
msg->cprbx.domain = AP_QID_QUEUE(aq->qid);
rc = ap_send(aq->qid, 0x0102030405060708ULL, ap_msg.msg, ap_msg.len);
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.msg, 4096);
if (rc == 0 && psmid == 0x0102030405060708ULL)
break;
}
if (i >= 2 * HZ) {
/* Got no answer. */
rc = -ENODEV;
goto out_free;
}
reply = ap_msg.msg;
if (reply->cprbx.ccp_rtcode == 0 && reply->cprbx.ccp_rscode == 0)
rc = 1;
else
rc = 0;
out_free:
free_page((unsigned long) ap_msg.msg);
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";
zc->speed_rating = 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";
zc->speed_rating = 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;
}
if (ap_test_bit(&ac->functions, AP_FUNC_COPRO)) {
rc = sysfs_create_group(&ap_dev->device.kobj,
&cca_card_attr_grp);
if (rc) {
zcrypt_card_unregister(zc);
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 ap_card *ac = to_ap_card(&ap_dev->device);
struct zcrypt_card *zc = to_ap_card(&ap_dev->device)->private;
if (ap_test_bit(&ac->functions, AP_FUNC_COPRO))
sysfs_remove_group(&ap_dev->device.kobj, &cca_card_attr_grp);
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);
ap_rapq(aq->qid);
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_state(aq);
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;
}
if (ap_test_bit(&aq->card->functions, AP_FUNC_COPRO)) {
rc = sysfs_create_group(&ap_dev->device.kobj,
&cca_queue_attr_grp);
if (rc) {
zcrypt_queue_unregister(zq);
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 (ap_test_bit(&aq->card->functions, AP_FUNC_COPRO))
sysfs_remove_group(&ap_dev->device.kobj, &cca_queue_attr_grp);
if (zq)
zcrypt_queue_unregister(zq);
}
static struct ap_driver zcrypt_cex2c_queue_driver = {
.probe = zcrypt_cex2c_queue_probe,
.remove = zcrypt_cex2c_queue_remove,
.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);