1/* 2 * linux/drivers/s390/crypto/zcrypt_cex2a.c 3 * 4 * zcrypt 2.1.0 5 * 6 * Copyright (C) 2001, 2006 IBM Corporation 7 * Author(s): Robert Burroughs 8 * Eric Rossman (edrossma@us.ibm.com) 9 * 10 * Hotplug & misc device support: Jochen Roehrig (roehrig@de.ibm.com) 11 * Major cleanup & driver split: Martin Schwidefsky <schwidefsky@de.ibm.com> 12 * Ralph Wuerthner <rwuerthn@de.ibm.com> 13 * 14 * This program is free software; you can redistribute it and/or modify 15 * it under the terms of the GNU General Public License as published by 16 * the Free Software Foundation; either version 2, or (at your option) 17 * any later version. 18 * 19 * This program is distributed in the hope that it will be useful, 20 * but WITHOUT ANY WARRANTY; without even the implied warranty of 21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 22 * GNU General Public License for more details. 23 * 24 * You should have received a copy of the GNU General Public License 25 * along with this program; if not, write to the Free Software 26 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 27 */ 28 29#include <linux/module.h> 30#include <linux/slab.h> 31#include <linux/init.h> 32#include <linux/err.h> 33#include <asm/atomic.h> 34#include <asm/uaccess.h> 35 36#include "ap_bus.h" 37#include "zcrypt_api.h" 38#include "zcrypt_error.h" 39#include "zcrypt_cex2a.h" 40 41#define CEX2A_MIN_MOD_SIZE 1 /* 8 bits */ 42#define CEX2A_MAX_MOD_SIZE 256 /* 2048 bits */ 43#define CEX3A_MIN_MOD_SIZE CEX2A_MIN_MOD_SIZE 44#define CEX3A_MAX_MOD_SIZE CEX2A_MAX_MOD_SIZE 45 46#define CEX2A_SPEED_RATING 970 47#define CEX3A_SPEED_RATING 900 48 49#define CEX2A_MAX_MESSAGE_SIZE 0x390 /* sizeof(struct type50_crb2_msg) */ 50#define CEX2A_MAX_RESPONSE_SIZE 0x110 /* max outputdatalength + type80_hdr */ 51 52#define CEX3A_MAX_MESSAGE_SIZE CEX2A_MAX_MESSAGE_SIZE 53#define CEX3A_MAX_RESPONSE_SIZE CEX2A_MAX_RESPONSE_SIZE 54 55#define CEX2A_CLEANUP_TIME (15*HZ) 56#define CEX3A_CLEANUP_TIME CEX2A_CLEANUP_TIME 57 58static struct ap_device_id zcrypt_cex2a_ids[] = { 59 { AP_DEVICE(AP_DEVICE_TYPE_CEX2A) }, 60 { AP_DEVICE(AP_DEVICE_TYPE_CEX3A) }, 61 { /* end of list */ }, 62}; 63 64#ifndef CONFIG_ZCRYPT_MONOLITHIC 65MODULE_DEVICE_TABLE(ap, zcrypt_cex2a_ids); 66MODULE_AUTHOR("IBM Corporation"); 67MODULE_DESCRIPTION("CEX2A Cryptographic Coprocessor device driver, " 68 "Copyright 2001, 2006 IBM Corporation"); 69MODULE_LICENSE("GPL"); 70#endif 71 72static int zcrypt_cex2a_probe(struct ap_device *ap_dev); 73static void zcrypt_cex2a_remove(struct ap_device *ap_dev); 74static void zcrypt_cex2a_receive(struct ap_device *, struct ap_message *, 75 struct ap_message *); 76 77static struct ap_driver zcrypt_cex2a_driver = { 78 .probe = zcrypt_cex2a_probe, 79 .remove = zcrypt_cex2a_remove, 80 .receive = zcrypt_cex2a_receive, 81 .ids = zcrypt_cex2a_ids, 82 .request_timeout = CEX2A_CLEANUP_TIME, 83}; 84 85/** 86 * Convert a ICAMEX message to a type50 MEX message. 87 * 88 * @zdev: crypto device pointer 89 * @zreq: crypto request pointer 90 * @mex: pointer to user input data 91 * 92 * Returns 0 on success or -EFAULT. 93 */ 94static int ICAMEX_msg_to_type50MEX_msg(struct zcrypt_device *zdev, 95 struct ap_message *ap_msg, 96 struct ica_rsa_modexpo *mex) 97{ 98 unsigned char *mod, *exp, *inp; 99 int mod_len; 100 101 mod_len = mex->inputdatalength; 102 103 if (mod_len <= 128) { 104 struct type50_meb1_msg *meb1 = ap_msg->message; 105 memset(meb1, 0, sizeof(*meb1)); 106 ap_msg->length = sizeof(*meb1); 107 meb1->header.msg_type_code = TYPE50_TYPE_CODE; 108 meb1->header.msg_len = sizeof(*meb1); 109 meb1->keyblock_type = TYPE50_MEB1_FMT; 110 mod = meb1->modulus + sizeof(meb1->modulus) - mod_len; 111 exp = meb1->exponent + sizeof(meb1->exponent) - mod_len; 112 inp = meb1->message + sizeof(meb1->message) - mod_len; 113 } else { 114 struct type50_meb2_msg *meb2 = ap_msg->message; 115 memset(meb2, 0, sizeof(*meb2)); 116 ap_msg->length = sizeof(*meb2); 117 meb2->header.msg_type_code = TYPE50_TYPE_CODE; 118 meb2->header.msg_len = sizeof(*meb2); 119 meb2->keyblock_type = TYPE50_MEB2_FMT; 120 mod = meb2->modulus + sizeof(meb2->modulus) - mod_len; 121 exp = meb2->exponent + sizeof(meb2->exponent) - mod_len; 122 inp = meb2->message + sizeof(meb2->message) - mod_len; 123 } 124 125 if (copy_from_user(mod, mex->n_modulus, mod_len) || 126 copy_from_user(exp, mex->b_key, mod_len) || 127 copy_from_user(inp, mex->inputdata, mod_len)) 128 return -EFAULT; 129 return 0; 130} 131 132/** 133 * Convert a ICACRT message to a type50 CRT message. 134 * 135 * @zdev: crypto device pointer 136 * @zreq: crypto request pointer 137 * @crt: pointer to user input data 138 * 139 * Returns 0 on success or -EFAULT. 140 */ 141static int ICACRT_msg_to_type50CRT_msg(struct zcrypt_device *zdev, 142 struct ap_message *ap_msg, 143 struct ica_rsa_modexpo_crt *crt) 144{ 145 int mod_len, short_len, long_len, long_offset; 146 unsigned char *p, *q, *dp, *dq, *u, *inp; 147 148 mod_len = crt->inputdatalength; 149 short_len = mod_len / 2; 150 long_len = mod_len / 2 + 8; 151 152 /* 153 * CEX2A cannot handle p, dp, or U > 128 bytes. 154 * If we have one of these, we need to do extra checking. 155 */ 156 if (long_len > 128) { 157 /* 158 * zcrypt_rsa_crt already checked for the leading 159 * zeroes of np_prime, bp_key and u_mult_inc. 160 */ 161 long_offset = long_len - 128; 162 long_len = 128; 163 } else 164 long_offset = 0; 165 166 /* 167 * Instead of doing extra work for p, dp, U > 64 bytes, we'll just use 168 * the larger message structure. 169 */ 170 if (long_len <= 64) { 171 struct type50_crb1_msg *crb1 = ap_msg->message; 172 memset(crb1, 0, sizeof(*crb1)); 173 ap_msg->length = sizeof(*crb1); 174 crb1->header.msg_type_code = TYPE50_TYPE_CODE; 175 crb1->header.msg_len = sizeof(*crb1); 176 crb1->keyblock_type = TYPE50_CRB1_FMT; 177 p = crb1->p + sizeof(crb1->p) - long_len; 178 q = crb1->q + sizeof(crb1->q) - short_len; 179 dp = crb1->dp + sizeof(crb1->dp) - long_len; 180 dq = crb1->dq + sizeof(crb1->dq) - short_len; 181 u = crb1->u + sizeof(crb1->u) - long_len; 182 inp = crb1->message + sizeof(crb1->message) - mod_len; 183 } else { 184 struct type50_crb2_msg *crb2 = ap_msg->message; 185 memset(crb2, 0, sizeof(*crb2)); 186 ap_msg->length = sizeof(*crb2); 187 crb2->header.msg_type_code = TYPE50_TYPE_CODE; 188 crb2->header.msg_len = sizeof(*crb2); 189 crb2->keyblock_type = TYPE50_CRB2_FMT; 190 p = crb2->p + sizeof(crb2->p) - long_len; 191 q = crb2->q + sizeof(crb2->q) - short_len; 192 dp = crb2->dp + sizeof(crb2->dp) - long_len; 193 dq = crb2->dq + sizeof(crb2->dq) - short_len; 194 u = crb2->u + sizeof(crb2->u) - long_len; 195 inp = crb2->message + sizeof(crb2->message) - mod_len; 196 } 197 198 if (copy_from_user(p, crt->np_prime + long_offset, long_len) || 199 copy_from_user(q, crt->nq_prime, short_len) || 200 copy_from_user(dp, crt->bp_key + long_offset, long_len) || 201 copy_from_user(dq, crt->bq_key, short_len) || 202 copy_from_user(u, crt->u_mult_inv + long_offset, long_len) || 203 copy_from_user(inp, crt->inputdata, mod_len)) 204 return -EFAULT; 205 206 207 return 0; 208} 209 210/** 211 * Copy results from a type 80 reply message back to user space. 212 * 213 * @zdev: crypto device pointer 214 * @reply: reply AP message. 215 * @data: pointer to user output data 216 * @length: size of user output data 217 * 218 * Returns 0 on success or -EFAULT. 219 */ 220static int convert_type80(struct zcrypt_device *zdev, 221 struct ap_message *reply, 222 char __user *outputdata, 223 unsigned int outputdatalength) 224{ 225 struct type80_hdr *t80h = reply->message; 226 unsigned char *data; 227 228 if (t80h->len < sizeof(*t80h) + outputdatalength) { 229 /* The result is too short, the CEX2A card may not do that.. */ 230 zdev->online = 0; 231 return -EAGAIN; /* repeat the request on a different device. */ 232 } 233 BUG_ON(t80h->len > CEX2A_MAX_RESPONSE_SIZE); 234 data = reply->message + t80h->len - outputdatalength; 235 if (copy_to_user(outputdata, data, outputdatalength)) 236 return -EFAULT; 237 return 0; 238} 239 240static int convert_response(struct zcrypt_device *zdev, 241 struct ap_message *reply, 242 char __user *outputdata, 243 unsigned int outputdatalength) 244{ 245 /* Response type byte is the second byte in the response. */ 246 switch (((unsigned char *) reply->message)[1]) { 247 case TYPE82_RSP_CODE: 248 case TYPE88_RSP_CODE: 249 return convert_error(zdev, reply); 250 case TYPE80_RSP_CODE: 251 return convert_type80(zdev, reply, 252 outputdata, outputdatalength); 253 default: /* Unknown response type, this should NEVER EVER happen */ 254 zdev->online = 0; 255 return -EAGAIN; /* repeat the request on a different device. */ 256 } 257} 258 259/** 260 * This function is called from the AP bus code after a crypto request 261 * "msg" has finished with the reply message "reply". 262 * It is called from tasklet context. 263 * @ap_dev: pointer to the AP device 264 * @msg: pointer to the AP message 265 * @reply: pointer to the AP reply message 266 */ 267static void zcrypt_cex2a_receive(struct ap_device *ap_dev, 268 struct ap_message *msg, 269 struct ap_message *reply) 270{ 271 static struct error_hdr error_reply = { 272 .type = TYPE82_RSP_CODE, 273 .reply_code = REP82_ERROR_MACHINE_FAILURE, 274 }; 275 struct type80_hdr *t80h; 276 int length; 277 278 /* Copy the reply message to the request message buffer. */ 279 if (IS_ERR(reply)) { 280 memcpy(msg->message, &error_reply, sizeof(error_reply)); 281 goto out; 282 } 283 t80h = reply->message; 284 if (t80h->type == TYPE80_RSP_CODE) { 285 length = min(CEX2A_MAX_RESPONSE_SIZE, (int) t80h->len); 286 memcpy(msg->message, reply->message, length); 287 } else 288 memcpy(msg->message, reply->message, sizeof error_reply); 289out: 290 complete((struct completion *) msg->private); 291} 292 293static atomic_t zcrypt_step = ATOMIC_INIT(0); 294 295/** 296 * The request distributor calls this function if it picked the CEX2A 297 * device to handle a modexpo request. 298 * @zdev: pointer to zcrypt_device structure that identifies the 299 * CEX2A device to the request distributor 300 * @mex: pointer to the modexpo request buffer 301 */ 302static long zcrypt_cex2a_modexpo(struct zcrypt_device *zdev, 303 struct ica_rsa_modexpo *mex) 304{ 305 struct ap_message ap_msg; 306 struct completion work; 307 int rc; 308 309 ap_init_message(&ap_msg); 310 ap_msg.message = kmalloc(CEX2A_MAX_MESSAGE_SIZE, GFP_KERNEL); 311 if (!ap_msg.message) 312 return -ENOMEM; 313 ap_msg.psmid = (((unsigned long long) current->pid) << 32) + 314 atomic_inc_return(&zcrypt_step); 315 ap_msg.private = &work; 316 rc = ICAMEX_msg_to_type50MEX_msg(zdev, &ap_msg, mex); 317 if (rc) 318 goto out_free; 319 init_completion(&work); 320 ap_queue_message(zdev->ap_dev, &ap_msg); 321 rc = wait_for_completion_interruptible(&work); 322 if (rc == 0) 323 rc = convert_response(zdev, &ap_msg, mex->outputdata, 324 mex->outputdatalength); 325 else 326 /* Signal pending. */ 327 ap_cancel_message(zdev->ap_dev, &ap_msg); 328out_free: 329 kfree(ap_msg.message); 330 return rc; 331} 332 333/** 334 * The request distributor calls this function if it picked the CEX2A 335 * device to handle a modexpo_crt request. 336 * @zdev: pointer to zcrypt_device structure that identifies the 337 * CEX2A device to the request distributor 338 * @crt: pointer to the modexpoc_crt request buffer 339 */ 340static long zcrypt_cex2a_modexpo_crt(struct zcrypt_device *zdev, 341 struct ica_rsa_modexpo_crt *crt) 342{ 343 struct ap_message ap_msg; 344 struct completion work; 345 int rc; 346 347 ap_init_message(&ap_msg); 348 ap_msg.message = kmalloc(CEX2A_MAX_MESSAGE_SIZE, GFP_KERNEL); 349 if (!ap_msg.message) 350 return -ENOMEM; 351 ap_msg.psmid = (((unsigned long long) current->pid) << 32) + 352 atomic_inc_return(&zcrypt_step); 353 ap_msg.private = &work; 354 rc = ICACRT_msg_to_type50CRT_msg(zdev, &ap_msg, crt); 355 if (rc) 356 goto out_free; 357 init_completion(&work); 358 ap_queue_message(zdev->ap_dev, &ap_msg); 359 rc = wait_for_completion_interruptible(&work); 360 if (rc == 0) 361 rc = convert_response(zdev, &ap_msg, crt->outputdata, 362 crt->outputdatalength); 363 else 364 /* Signal pending. */ 365 ap_cancel_message(zdev->ap_dev, &ap_msg); 366out_free: 367 kfree(ap_msg.message); 368 return rc; 369} 370 371/** 372 * The crypto operations for a CEX2A card. 373 */ 374static struct zcrypt_ops zcrypt_cex2a_ops = { 375 .rsa_modexpo = zcrypt_cex2a_modexpo, 376 .rsa_modexpo_crt = zcrypt_cex2a_modexpo_crt, 377}; 378 379/** 380 * Probe function for CEX2A cards. It always accepts the AP device 381 * since the bus_match already checked the hardware type. 382 * @ap_dev: pointer to the AP device. 383 */ 384static int zcrypt_cex2a_probe(struct ap_device *ap_dev) 385{ 386 struct zcrypt_device *zdev = NULL; 387 int rc = 0; 388 389 switch (ap_dev->device_type) { 390 case AP_DEVICE_TYPE_CEX2A: 391 zdev = zcrypt_device_alloc(CEX2A_MAX_RESPONSE_SIZE); 392 if (!zdev) 393 return -ENOMEM; 394 zdev->user_space_type = ZCRYPT_CEX2A; 395 zdev->type_string = "CEX2A"; 396 zdev->min_mod_size = CEX2A_MIN_MOD_SIZE; 397 zdev->max_mod_size = CEX2A_MAX_MOD_SIZE; 398 zdev->short_crt = 1; 399 zdev->speed_rating = CEX2A_SPEED_RATING; 400 break; 401 case AP_DEVICE_TYPE_CEX3A: 402 zdev = zcrypt_device_alloc(CEX3A_MAX_RESPONSE_SIZE); 403 if (!zdev) 404 return -ENOMEM; 405 zdev->user_space_type = ZCRYPT_CEX3A; 406 zdev->type_string = "CEX3A"; 407 zdev->min_mod_size = CEX3A_MIN_MOD_SIZE; 408 zdev->max_mod_size = CEX3A_MAX_MOD_SIZE; 409 zdev->short_crt = 1; 410 zdev->speed_rating = CEX3A_SPEED_RATING; 411 break; 412 } 413 if (zdev != NULL) { 414 zdev->ap_dev = ap_dev; 415 zdev->ops = &zcrypt_cex2a_ops; 416 zdev->online = 1; 417 ap_dev->reply = &zdev->reply; 418 ap_dev->private = zdev; 419 rc = zcrypt_device_register(zdev); 420 } 421 if (rc) { 422 ap_dev->private = NULL; 423 zcrypt_device_free(zdev); 424 } 425 return rc; 426} 427 428/** 429 * This is called to remove the extended CEX2A driver information 430 * if an AP device is removed. 431 */ 432static void zcrypt_cex2a_remove(struct ap_device *ap_dev) 433{ 434 struct zcrypt_device *zdev = ap_dev->private; 435 436 zcrypt_device_unregister(zdev); 437} 438 439int __init zcrypt_cex2a_init(void) 440{ 441 return ap_driver_register(&zcrypt_cex2a_driver, THIS_MODULE, "cex2a"); 442} 443 444void __exit zcrypt_cex2a_exit(void) 445{ 446 ap_driver_unregister(&zcrypt_cex2a_driver); 447} 448 449#ifndef CONFIG_ZCRYPT_MONOLITHIC 450module_init(zcrypt_cex2a_init); 451module_exit(zcrypt_cex2a_exit); 452#endif 453