/*
* linux/drivers/s390/crypto/zcrypt_pcica.c
*
* zcrypt 2.1.0
*
* Copyright (C) 2001, 2006 IBM Corporation
* 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>
*
* 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
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
#include <asm/atomic.h>
#include <asm/uaccess.h>
#include "ap_bus.h"
#include "zcrypt_api.h"
#include "zcrypt_error.h"
#include "zcrypt_pcica.h"
#define PCICA_MIN_MOD_SIZE 1 /* 8 bits */
#define PCICA_MAX_MOD_SIZE 256 /* 2048 bits */
#define PCICA_SPEED_RATING 2800
#define PCICA_MAX_MESSAGE_SIZE 0x3a0 /* sizeof(struct type4_lcr) */
#define PCICA_MAX_RESPONSE_SIZE 0x110 /* max outputdatalength + type80_hdr */
#define PCICA_CLEANUP_TIME (15*HZ)
static struct ap_device_id zcrypt_pcica_ids[] = {
{ AP_DEVICE(AP_DEVICE_TYPE_PCICA) },
{ /* end of list */ },
};
#ifndef CONFIG_ZCRYPT_MONOLITHIC
MODULE_DEVICE_TABLE(ap, zcrypt_pcica_ids);
MODULE_AUTHOR("IBM Corporation");
MODULE_DESCRIPTION("PCICA Cryptographic Coprocessor device driver, "
"Copyright 2001, 2006 IBM Corporation");
MODULE_LICENSE("GPL");
#endif
static int zcrypt_pcica_probe(struct ap_device *ap_dev);
static void zcrypt_pcica_remove(struct ap_device *ap_dev);
static void zcrypt_pcica_receive(struct ap_device *, struct ap_message *,
struct ap_message *);
static struct ap_driver zcrypt_pcica_driver = {
.probe = zcrypt_pcica_probe,
.remove = zcrypt_pcica_remove,
.receive = zcrypt_pcica_receive,
.ids = zcrypt_pcica_ids,
.request_timeout = PCICA_CLEANUP_TIME,
};
/**
* Convert a ICAMEX message to a type4 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_type4MEX_msg(struct zcrypt_device *zdev,
struct ap_message *ap_msg,
struct ica_rsa_modexpo *mex)
{
unsigned char *modulus, *exponent, *message;
int mod_len;
mod_len = mex->inputdatalength;
if (mod_len <= 128) {
struct type4_sme *sme = ap_msg->message;
memset(sme, 0, sizeof(*sme));
ap_msg->length = sizeof(*sme);
sme->header.msg_fmt = TYPE4_SME_FMT;
sme->header.msg_len = sizeof(*sme);
sme->header.msg_type_code = TYPE4_TYPE_CODE;
sme->header.request_code = TYPE4_REQU_CODE;
modulus = sme->modulus + sizeof(sme->modulus) - mod_len;
exponent = sme->exponent + sizeof(sme->exponent) - mod_len;
message = sme->message + sizeof(sme->message) - mod_len;
} else {
struct type4_lme *lme = ap_msg->message;
memset(lme, 0, sizeof(*lme));
ap_msg->length = sizeof(*lme);
lme->header.msg_fmt = TYPE4_LME_FMT;
lme->header.msg_len = sizeof(*lme);
lme->header.msg_type_code = TYPE4_TYPE_CODE;
lme->header.request_code = TYPE4_REQU_CODE;
modulus = lme->modulus + sizeof(lme->modulus) - mod_len;
exponent = lme->exponent + sizeof(lme->exponent) - mod_len;
message = lme->message + sizeof(lme->message) - mod_len;
}
if (copy_from_user(modulus, mex->n_modulus, mod_len) ||
copy_from_user(exponent, mex->b_key, mod_len) ||
copy_from_user(message, mex->inputdata, mod_len))
return -EFAULT;
return 0;
}
/**
* Convert a ICACRT message to a type4 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_type4CRT_msg(struct zcrypt_device *zdev,
struct ap_message *ap_msg,
struct ica_rsa_modexpo_crt *crt)
{
unsigned char *p, *q, *dp, *dq, *u, *inp;
int mod_len, short_len, long_len;
mod_len = crt->inputdatalength;
short_len = mod_len / 2;
long_len = mod_len / 2 + 8;
if (mod_len <= 128) {
struct type4_scr *scr = ap_msg->message;
memset(scr, 0, sizeof(*scr));
ap_msg->length = sizeof(*scr);
scr->header.msg_type_code = TYPE4_TYPE_CODE;
scr->header.request_code = TYPE4_REQU_CODE;
scr->header.msg_fmt = TYPE4_SCR_FMT;
scr->header.msg_len = sizeof(*scr);
p = scr->p + sizeof(scr->p) - long_len;
q = scr->q + sizeof(scr->q) - short_len;
dp = scr->dp + sizeof(scr->dp) - long_len;
dq = scr->dq + sizeof(scr->dq) - short_len;
u = scr->u + sizeof(scr->u) - long_len;
inp = scr->message + sizeof(scr->message) - mod_len;
} else {
struct type4_lcr *lcr = ap_msg->message;
memset(lcr, 0, sizeof(*lcr));
ap_msg->length = sizeof(*lcr);
lcr->header.msg_type_code = TYPE4_TYPE_CODE;
lcr->header.request_code = TYPE4_REQU_CODE;
lcr->header.msg_fmt = TYPE4_LCR_FMT;
lcr->header.msg_len = sizeof(*lcr);
p = lcr->p + sizeof(lcr->p) - long_len;
q = lcr->q + sizeof(lcr->q) - short_len;
dp = lcr->dp + sizeof(lcr->dp) - long_len;
dq = lcr->dq + sizeof(lcr->dq) - short_len;
u = lcr->u + sizeof(lcr->u) - long_len;
inp = lcr->message + sizeof(lcr->message) - mod_len;
}
if (copy_from_user(p, crt->np_prime, long_len) ||
copy_from_user(q, crt->nq_prime, short_len) ||
copy_from_user(dp, crt->bp_key, long_len) ||
copy_from_user(dq, crt->bq_key, short_len) ||
copy_from_user(u, crt->u_mult_inv, long_len) ||
copy_from_user(inp, crt->inputdata, mod_len))
return -EFAULT;
return 0;
}
/**
* Copy results from a type 84 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_type84(struct zcrypt_device *zdev,
struct ap_message *reply,
char __user *outputdata,
unsigned int outputdatalength)
{
struct type84_hdr *t84h = reply->message;
char *data;
if (t84h->len < sizeof(*t84h) + outputdatalength) {
/* The result is too short, the PCICA card may not do that.. */
zdev->online = 0;
return -EAGAIN; /* repeat the request on a different device. */
}
BUG_ON(t84h->len > PCICA_MAX_RESPONSE_SIZE);
data = reply->message + t84h->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 TYPE84_RSP_CODE:
return convert_type84(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_pcica_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 type84_hdr *t84h;
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;
}
t84h = reply->message;
if (t84h->code == TYPE84_RSP_CODE) {
length = min(PCICA_MAX_RESPONSE_SIZE, (int) t84h->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 PCICA
* device to handle a modexpo request.
* @zdev: pointer to zcrypt_device structure that identifies the
* PCICA device to the request distributor
* @mex: pointer to the modexpo request buffer
*/
static long zcrypt_pcica_modexpo(struct zcrypt_device *zdev,
struct ica_rsa_modexpo *mex)
{
struct ap_message ap_msg;
struct completion work;
int rc;
ap_msg.message = kmalloc(PCICA_MAX_MESSAGE_SIZE, GFP_KERNEL);
if (!ap_msg.message)
return -ENOMEM;
ap_msg.psmid = (((unsigned long long) current->pid) << 32) +
atomic_inc_return(&zcrypt_step);
ap_msg.private = &work;
rc = ICAMEX_msg_to_type4MEX_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 PCICA
* device to handle a modexpo_crt request.
* @zdev: pointer to zcrypt_device structure that identifies the
* PCICA device to the request distributor
* @crt: pointer to the modexpoc_crt request buffer
*/
static long zcrypt_pcica_modexpo_crt(struct zcrypt_device *zdev,
struct ica_rsa_modexpo_crt *crt)
{
struct ap_message ap_msg;
struct completion work;
int rc;
ap_msg.message = kmalloc(PCICA_MAX_MESSAGE_SIZE, GFP_KERNEL);
if (!ap_msg.message)
return -ENOMEM;
ap_msg.psmid = (((unsigned long long) current->pid) << 32) +
atomic_inc_return(&zcrypt_step);
ap_msg.private = &work;
rc = ICACRT_msg_to_type4CRT_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 PCICA card.
*/
static struct zcrypt_ops zcrypt_pcica_ops = {
.rsa_modexpo = zcrypt_pcica_modexpo,
.rsa_modexpo_crt = zcrypt_pcica_modexpo_crt,
};
/**
* Probe function for PCICA cards. It always accepts the AP device
* since the bus_match already checked the hardware type.
* @ap_dev: pointer to the AP device.
*/
static int zcrypt_pcica_probe(struct ap_device *ap_dev)
{
struct zcrypt_device *zdev;
int rc;
zdev = zcrypt_device_alloc(PCICA_MAX_RESPONSE_SIZE);
if (!zdev)
return -ENOMEM;
zdev->ap_dev = ap_dev;
zdev->ops = &zcrypt_pcica_ops;
zdev->online = 1;
zdev->user_space_type = ZCRYPT_PCICA;
zdev->type_string = "PCICA";
zdev->min_mod_size = PCICA_MIN_MOD_SIZE;
zdev->max_mod_size = PCICA_MAX_MOD_SIZE;
zdev->speed_rating = PCICA_SPEED_RATING;
ap_dev->reply = &zdev->reply;
ap_dev->private = zdev;
rc = zcrypt_device_register(zdev);
if (rc)
goto out_free;
return 0;
out_free:
ap_dev->private = NULL;
zcrypt_device_free(zdev);
return rc;
}
/**
* This is called to remove the extended PCICA driver information
* if an AP device is removed.
*/
static void zcrypt_pcica_remove(struct ap_device *ap_dev)
{
struct zcrypt_device *zdev = ap_dev->private;
zcrypt_device_unregister(zdev);
}
int __init zcrypt_pcica_init(void)
{
return ap_driver_register(&zcrypt_pcica_driver, THIS_MODULE, "pcica");
}
void zcrypt_pcica_exit(void)
{
ap_driver_unregister(&zcrypt_pcica_driver);
}
#ifndef CONFIG_ZCRYPT_MONOLITHIC
module_init(zcrypt_pcica_init);
module_exit(zcrypt_pcica_exit);
#endif
