diff options
Diffstat (limited to 'drivers/s390/crypto/zcrypt_cex2a.c')
| -rw-r--r-- | drivers/s390/crypto/zcrypt_cex2a.c | 435 |
1 files changed, 435 insertions, 0 deletions
diff --git a/drivers/s390/crypto/zcrypt_cex2a.c b/drivers/s390/crypto/zcrypt_cex2a.c new file mode 100644 index 00000000000..a62b00083d0 --- /dev/null +++ b/drivers/s390/crypto/zcrypt_cex2a.c @@ -0,0 +1,435 @@ +/* + * linux/drivers/s390/crypto/zcrypt_cex2a.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_cex2a.h" + +#define CEX2A_MIN_MOD_SIZE 1 /* 8 bits */ +#define CEX2A_MAX_MOD_SIZE 256 /* 2048 bits */ + +#define CEX2A_SPEED_RATING 970 + +#define CEX2A_MAX_MESSAGE_SIZE 0x390 /* sizeof(struct type50_crb2_msg) */ +#define CEX2A_MAX_RESPONSE_SIZE 0x110 /* max outputdatalength + type80_hdr */ + +#define CEX2A_CLEANUP_TIME (15*HZ) + +static struct ap_device_id zcrypt_cex2a_ids[] = { + { AP_DEVICE(AP_DEVICE_TYPE_CEX2A) }, + { /* end of list */ }, +}; + +#ifndef CONFIG_ZCRYPT_MONOLITHIC +MODULE_DEVICE_TABLE(ap, zcrypt_cex2a_ids); +MODULE_AUTHOR("IBM Corporation"); +MODULE_DESCRIPTION("CEX2A Cryptographic Coprocessor device driver, " + "Copyright 2001, 2006 IBM Corporation"); +MODULE_LICENSE("GPL"); +#endif + +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, + .remove = zcrypt_cex2a_remove, + .receive = zcrypt_cex2a_receive, + .ids = zcrypt_cex2a_ids, +}; + +/** + * 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 { + 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; + } + + 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; + 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. + */ + if (long_len > 128) { + /* + * zcrypt_rsa_crt already checked for the leading + * zeroes of np_prime, bp_key and u_mult_inc. + */ + long_offset = long_len - 128; + long_len = 128; + } 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 { + 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; + } + + 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. */ + } + BUG_ON(t80h->len > CEX2A_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 */ + PRINTK("Unrecognized Message Header: %08x%08x\n", + *(unsigned int *) reply->message, + *(unsigned int *) (reply->message+4)); + 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 = reply->message; + int length; + + /* Copy the reply message to the request message buffer. */ + if (IS_ERR(reply)) + memcpy(msg->message, &error_reply, sizeof(error_reply)); + else if (t80h->type == TYPE80_RSP_CODE) { + length = min(CEX2A_MAX_RESPONSE_SIZE, (int) t80h->len); + memcpy(msg->message, reply->message, length); + } else + memcpy(msg->message, reply->message, sizeof error_reply); + 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_msg.message = (void *) kmalloc(CEX2A_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_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_timeout( + &work, CEX2A_CLEANUP_TIME); + if (rc > 0) + rc = convert_response(zdev, &ap_msg, mex->outputdata, + mex->outputdatalength); + else { + /* Signal pending or message timed out. */ + ap_cancel_message(zdev->ap_dev, &ap_msg); + if (rc == 0) + /* Message timed out. */ + rc = -ETIME; + } +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_msg.message = (void *) kmalloc(CEX2A_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_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_timeout( + &work, CEX2A_CLEANUP_TIME); + if (rc > 0) + rc = convert_response(zdev, &ap_msg, crt->outputdata, + crt->outputdatalength); + else { + /* Signal pending or message timed out. */ + ap_cancel_message(zdev->ap_dev, &ap_msg); + if (rc == 0) + /* Message timed out. */ + rc = -ETIME; + } +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. + * @ap_dev: pointer to the AP device. + */ +static int zcrypt_cex2a_probe(struct ap_device *ap_dev) +{ + struct zcrypt_device *zdev; + int rc; + + zdev = zcrypt_device_alloc(CEX2A_MAX_RESPONSE_SIZE); + if (!zdev) + return -ENOMEM; + zdev->ap_dev = ap_dev; + zdev->ops = &zcrypt_cex2a_ops; + zdev->online = 1; + zdev->user_space_type = ZCRYPT_CEX2A; + zdev->type_string = "CEX2A"; + zdev->min_mod_size = CEX2A_MIN_MOD_SIZE; + zdev->max_mod_size = CEX2A_MAX_MOD_SIZE; + zdev->short_crt = 1; + zdev->speed_rating = CEX2A_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 CEX2A driver information + * if an AP device is removed. + */ +static void zcrypt_cex2a_remove(struct ap_device *ap_dev) +{ + struct zcrypt_device *zdev = ap_dev->private; + + zcrypt_device_unregister(zdev); +} + +int __init zcrypt_cex2a_init(void) +{ + return ap_driver_register(&zcrypt_cex2a_driver, THIS_MODULE, "cex2a"); +} + +void __exit zcrypt_cex2a_exit(void) +{ + ap_driver_unregister(&zcrypt_cex2a_driver); +} + +#ifndef CONFIG_ZCRYPT_MONOLITHIC +module_init(zcrypt_cex2a_init); +module_exit(zcrypt_cex2a_exit); +#endif |