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 <linux/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 512 /* 4096 bits */ 45 46#define CEX2A_SPEED_RATING 970 47#define CEX3A_SPEED_RATING 900 /* Fixme: Needs finetuning */ 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_RESPONSE_SIZE 0x210 /* 512 bit modulus 53 * (max outputdatalength) + 54 * type80_hdr*/ 55#define CEX3A_MAX_MESSAGE_SIZE sizeof(struct type50_crb3_msg) 56 57#define CEX2A_CLEANUP_TIME (15*HZ) 58#define CEX3A_CLEANUP_TIME CEX2A_CLEANUP_TIME 59 60static struct ap_device_id zcrypt_cex2a_ids[] = { 61 { AP_DEVICE(AP_DEVICE_TYPE_CEX2A) }, 62 { AP_DEVICE(AP_DEVICE_TYPE_CEX3A) }, 63 { /* end of list */ }, 64}; 65 66MODULE_DEVICE_TABLE(ap, zcrypt_cex2a_ids); 67MODULE_AUTHOR("IBM Corporation"); 68MODULE_DESCRIPTION("CEX2A Cryptographic Coprocessor device driver, " 69 "Copyright 2001, 2006 IBM Corporation"); 70MODULE_LICENSE("GPL"); 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 if (mod_len <= 256) { 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 } else { 124 /* mod_len > 256 = 4096 bit RSA Key */ 125 struct type50_meb3_msg *meb3 = ap_msg->message; 126 memset(meb3, 0, sizeof(*meb3)); 127 ap_msg->length = sizeof(*meb3); 128 meb3->header.msg_type_code = TYPE50_TYPE_CODE; 129 meb3->header.msg_len = sizeof(*meb3); 130 meb3->keyblock_type = TYPE50_MEB3_FMT; 131 mod = meb3->modulus + sizeof(meb3->modulus) - mod_len; 132 exp = meb3->exponent + sizeof(meb3->exponent) - mod_len; 133 inp = meb3->message + sizeof(meb3->message) - mod_len; 134 } 135 136 if (copy_from_user(mod, mex->n_modulus, mod_len) || 137 copy_from_user(exp, mex->b_key, mod_len) || 138 copy_from_user(inp, mex->inputdata, mod_len)) 139 return -EFAULT; 140 return 0; 141} 142 143/** 144 * Convert a ICACRT message to a type50 CRT message. 145 * 146 * @zdev: crypto device pointer 147 * @zreq: crypto request pointer 148 * @crt: pointer to user input data 149 * 150 * Returns 0 on success or -EFAULT. 151 */ 152static int ICACRT_msg_to_type50CRT_msg(struct zcrypt_device *zdev, 153 struct ap_message *ap_msg, 154 struct ica_rsa_modexpo_crt *crt) 155{ 156 int mod_len, short_len, long_len, long_offset, limit; 157 unsigned char *p, *q, *dp, *dq, *u, *inp; 158 159 mod_len = crt->inputdatalength; 160 short_len = mod_len / 2; 161 long_len = mod_len / 2 + 8; 162 163 /* 164 * CEX2A cannot handle p, dp, or U > 128 bytes. 165 * If we have one of these, we need to do extra checking. 166 * For CEX3A the limit is 256 bytes. 167 */ 168 if (zdev->max_mod_size == CEX3A_MAX_MOD_SIZE) 169 limit = 256; 170 else 171 limit = 128; 172 173 if (long_len > limit) { 174 /* 175 * zcrypt_rsa_crt already checked for the leading 176 * zeroes of np_prime, bp_key and u_mult_inc. 177 */ 178 long_offset = long_len - limit; 179 long_len = limit; 180 } else 181 long_offset = 0; 182 183 /* 184 * Instead of doing extra work for p, dp, U > 64 bytes, we'll just use 185 * the larger message structure. 186 */ 187 if (long_len <= 64) { 188 struct type50_crb1_msg *crb1 = ap_msg->message; 189 memset(crb1, 0, sizeof(*crb1)); 190 ap_msg->length = sizeof(*crb1); 191 crb1->header.msg_type_code = TYPE50_TYPE_CODE; 192 crb1->header.msg_len = sizeof(*crb1); 193 crb1->keyblock_type = TYPE50_CRB1_FMT; 194 p = crb1->p + sizeof(crb1->p) - long_len; 195 q = crb1->q + sizeof(crb1->q) - short_len; 196 dp = crb1->dp + sizeof(crb1->dp) - long_len; 197 dq = crb1->dq + sizeof(crb1->dq) - short_len; 198 u = crb1->u + sizeof(crb1->u) - long_len; 199 inp = crb1->message + sizeof(crb1->message) - mod_len; 200 } else if (long_len <= 128) { 201 struct type50_crb2_msg *crb2 = ap_msg->message; 202 memset(crb2, 0, sizeof(*crb2)); 203 ap_msg->length = sizeof(*crb2); 204 crb2->header.msg_type_code = TYPE50_TYPE_CODE; 205 crb2->header.msg_len = sizeof(*crb2); 206 crb2->keyblock_type = TYPE50_CRB2_FMT; 207 p = crb2->p + sizeof(crb2->p) - long_len; 208 q = crb2->q + sizeof(crb2->q) - short_len; 209 dp = crb2->dp + sizeof(crb2->dp) - long_len; 210 dq = crb2->dq + sizeof(crb2->dq) - short_len; 211 u = crb2->u + sizeof(crb2->u) - long_len; 212 inp = crb2->message + sizeof(crb2->message) - mod_len; 213 } else { 214 /* long_len >= 256 */ 215 struct type50_crb3_msg *crb3 = ap_msg->message; 216 memset(crb3, 0, sizeof(*crb3)); 217 ap_msg->length = sizeof(*crb3); 218 crb3->header.msg_type_code = TYPE50_TYPE_CODE; 219 crb3->header.msg_len = sizeof(*crb3); 220 crb3->keyblock_type = TYPE50_CRB3_FMT; 221 p = crb3->p + sizeof(crb3->p) - long_len; 222 q = crb3->q + sizeof(crb3->q) - short_len; 223 dp = crb3->dp + sizeof(crb3->dp) - long_len; 224 dq = crb3->dq + sizeof(crb3->dq) - short_len; 225 u = crb3->u + sizeof(crb3->u) - long_len; 226 inp = crb3->message + sizeof(crb3->message) - mod_len; 227 } 228 229 if (copy_from_user(p, crt->np_prime + long_offset, long_len) || 230 copy_from_user(q, crt->nq_prime, short_len) || 231 copy_from_user(dp, crt->bp_key + long_offset, long_len) || 232 copy_from_user(dq, crt->bq_key, short_len) || 233 copy_from_user(u, crt->u_mult_inv + long_offset, long_len) || 234 copy_from_user(inp, crt->inputdata, mod_len)) 235 return -EFAULT; 236 237 return 0; 238} 239 240/** 241 * Copy results from a type 80 reply message back to user space. 242 * 243 * @zdev: crypto device pointer 244 * @reply: reply AP message. 245 * @data: pointer to user output data 246 * @length: size of user output data 247 * 248 * Returns 0 on success or -EFAULT. 249 */ 250static int convert_type80(struct zcrypt_device *zdev, 251 struct ap_message *reply, 252 char __user *outputdata, 253 unsigned int outputdatalength) 254{ 255 struct type80_hdr *t80h = reply->message; 256 unsigned char *data; 257 258 if (t80h->len < sizeof(*t80h) + outputdatalength) { 259 /* The result is too short, the CEX2A card may not do that.. */ 260 zdev->online = 0; 261 return -EAGAIN; /* repeat the request on a different device. */ 262 } 263 if (zdev->user_space_type == ZCRYPT_CEX2A) 264 BUG_ON(t80h->len > CEX2A_MAX_RESPONSE_SIZE); 265 else 266 BUG_ON(t80h->len > CEX3A_MAX_RESPONSE_SIZE); 267 data = reply->message + t80h->len - outputdatalength; 268 if (copy_to_user(outputdata, data, outputdatalength)) 269 return -EFAULT; 270 return 0; 271} 272 273static int convert_response(struct zcrypt_device *zdev, 274 struct ap_message *reply, 275 char __user *outputdata, 276 unsigned int outputdatalength) 277{ 278 /* Response type byte is the second byte in the response. */ 279 switch (((unsigned char *) reply->message)[1]) { 280 case TYPE82_RSP_CODE: 281 case TYPE88_RSP_CODE: 282 return convert_error(zdev, reply); 283 case TYPE80_RSP_CODE: 284 return convert_type80(zdev, reply, 285 outputdata, outputdatalength); 286 default: /* Unknown response type, this should NEVER EVER happen */ 287 zdev->online = 0; 288 return -EAGAIN; /* repeat the request on a different device. */ 289 } 290} 291 292/** 293 * This function is called from the AP bus code after a crypto request 294 * "msg" has finished with the reply message "reply". 295 * It is called from tasklet context. 296 * @ap_dev: pointer to the AP device 297 * @msg: pointer to the AP message 298 * @reply: pointer to the AP reply message 299 */ 300static void zcrypt_cex2a_receive(struct ap_device *ap_dev, 301 struct ap_message *msg, 302 struct ap_message *reply) 303{ 304 static struct error_hdr error_reply = { 305 .type = TYPE82_RSP_CODE, 306 .reply_code = REP82_ERROR_MACHINE_FAILURE, 307 }; 308 struct type80_hdr *t80h; 309 int length; 310 311 /* Copy the reply message to the request message buffer. */ 312 if (IS_ERR(reply)) { 313 memcpy(msg->message, &error_reply, sizeof(error_reply)); 314 goto out; 315 } 316 t80h = reply->message; 317 if (t80h->type == TYPE80_RSP_CODE) { 318 if (ap_dev->device_type == AP_DEVICE_TYPE_CEX2A) 319 length = min(CEX2A_MAX_RESPONSE_SIZE, (int) t80h->len); 320 else 321 length = min(CEX3A_MAX_RESPONSE_SIZE, (int) t80h->len); 322 memcpy(msg->message, reply->message, length); 323 } else 324 memcpy(msg->message, reply->message, sizeof error_reply); 325out: 326 complete((struct completion *) msg->private); 327} 328 329static atomic_t zcrypt_step = ATOMIC_INIT(0); 330 331/** 332 * The request distributor calls this function if it picked the CEX2A 333 * device to handle a modexpo request. 334 * @zdev: pointer to zcrypt_device structure that identifies the 335 * CEX2A device to the request distributor 336 * @mex: pointer to the modexpo request buffer 337 */ 338static long zcrypt_cex2a_modexpo(struct zcrypt_device *zdev, 339 struct ica_rsa_modexpo *mex) 340{ 341 struct ap_message ap_msg; 342 struct completion work; 343 int rc; 344 345 ap_init_message(&ap_msg); 346 if (zdev->user_space_type == ZCRYPT_CEX2A) 347 ap_msg.message = kmalloc(CEX2A_MAX_MESSAGE_SIZE, GFP_KERNEL); 348 else 349 ap_msg.message = kmalloc(CEX3A_MAX_MESSAGE_SIZE, GFP_KERNEL); 350 if (!ap_msg.message) 351 return -ENOMEM; 352 ap_msg.psmid = (((unsigned long long) current->pid) << 32) + 353 atomic_inc_return(&zcrypt_step); 354 ap_msg.private = &work; 355 rc = ICAMEX_msg_to_type50MEX_msg(zdev, &ap_msg, mex); 356 if (rc) 357 goto out_free; 358 init_completion(&work); 359 ap_queue_message(zdev->ap_dev, &ap_msg); 360 rc = wait_for_completion_interruptible(&work); 361 if (rc == 0) 362 rc = convert_response(zdev, &ap_msg, mex->outputdata, 363 mex->outputdatalength); 364 else 365 /* Signal pending. */ 366 ap_cancel_message(zdev->ap_dev, &ap_msg); 367out_free: 368 kfree(ap_msg.message); 369 return rc; 370} 371 372/** 373 * The request distributor calls this function if it picked the CEX2A 374 * device to handle a modexpo_crt request. 375 * @zdev: pointer to zcrypt_device structure that identifies the 376 * CEX2A device to the request distributor 377 * @crt: pointer to the modexpoc_crt request buffer 378 */ 379static long zcrypt_cex2a_modexpo_crt(struct zcrypt_device *zdev, 380 struct ica_rsa_modexpo_crt *crt) 381{ 382 struct ap_message ap_msg; 383 struct completion work; 384 int rc; 385 386 ap_init_message(&ap_msg); 387 if (zdev->user_space_type == ZCRYPT_CEX2A) 388 ap_msg.message = kmalloc(CEX2A_MAX_MESSAGE_SIZE, GFP_KERNEL); 389 else 390 ap_msg.message = kmalloc(CEX3A_MAX_MESSAGE_SIZE, GFP_KERNEL); 391 if (!ap_msg.message) 392 return -ENOMEM; 393 ap_msg.psmid = (((unsigned long long) current->pid) << 32) + 394 atomic_inc_return(&zcrypt_step); 395 ap_msg.private = &work; 396 rc = ICACRT_msg_to_type50CRT_msg(zdev, &ap_msg, crt); 397 if (rc) 398 goto out_free; 399 init_completion(&work); 400 ap_queue_message(zdev->ap_dev, &ap_msg); 401 rc = wait_for_completion_interruptible(&work); 402 if (rc == 0) 403 rc = convert_response(zdev, &ap_msg, crt->outputdata, 404 crt->outputdatalength); 405 else 406 /* Signal pending. */ 407 ap_cancel_message(zdev->ap_dev, &ap_msg); 408out_free: 409 kfree(ap_msg.message); 410 return rc; 411} 412 413/** 414 * The crypto operations for a CEX2A card. 415 */ 416static struct zcrypt_ops zcrypt_cex2a_ops = { 417 .rsa_modexpo = zcrypt_cex2a_modexpo, 418 .rsa_modexpo_crt = zcrypt_cex2a_modexpo_crt, 419}; 420 421/** 422 * Probe function for CEX2A cards. It always accepts the AP device 423 * since the bus_match already checked the hardware type. 424 * @ap_dev: pointer to the AP device. 425 */ 426static int zcrypt_cex2a_probe(struct ap_device *ap_dev) 427{ 428 struct zcrypt_device *zdev = NULL; 429 int rc = 0; 430 431 switch (ap_dev->device_type) { 432 case AP_DEVICE_TYPE_CEX2A: 433 zdev = zcrypt_device_alloc(CEX2A_MAX_RESPONSE_SIZE); 434 if (!zdev) 435 return -ENOMEM; 436 zdev->user_space_type = ZCRYPT_CEX2A; 437 zdev->type_string = "CEX2A"; 438 zdev->min_mod_size = CEX2A_MIN_MOD_SIZE; 439 zdev->max_mod_size = CEX2A_MAX_MOD_SIZE; 440 zdev->short_crt = 1; 441 zdev->speed_rating = CEX2A_SPEED_RATING; 442 zdev->max_exp_bit_length = CEX2A_MAX_MOD_SIZE; 443 break; 444 case AP_DEVICE_TYPE_CEX3A: 445 zdev = zcrypt_device_alloc(CEX3A_MAX_RESPONSE_SIZE); 446 if (!zdev) 447 return -ENOMEM; 448 zdev->user_space_type = ZCRYPT_CEX3A; 449 zdev->type_string = "CEX3A"; 450 zdev->min_mod_size = CEX2A_MIN_MOD_SIZE; 451 zdev->max_mod_size = CEX2A_MAX_MOD_SIZE; 452 zdev->max_exp_bit_length = CEX2A_MAX_MOD_SIZE; 453 if (ap_4096_commands_available(ap_dev->qid)) { 454 zdev->max_mod_size = CEX3A_MAX_MOD_SIZE; 455 zdev->max_exp_bit_length = CEX3A_MAX_MOD_SIZE; 456 } 457 zdev->short_crt = 1; 458 zdev->speed_rating = CEX3A_SPEED_RATING; 459 break; 460 } 461 if (zdev != NULL) { 462 zdev->ap_dev = ap_dev; 463 zdev->ops = &zcrypt_cex2a_ops; 464 zdev->online = 1; 465 ap_dev->reply = &zdev->reply; 466 ap_dev->private = zdev; 467 rc = zcrypt_device_register(zdev); 468 } 469 if (rc) { 470 ap_dev->private = NULL; 471 zcrypt_device_free(zdev); 472 } 473 return rc; 474} 475 476/** 477 * This is called to remove the extended CEX2A driver information 478 * if an AP device is removed. 479 */ 480static void zcrypt_cex2a_remove(struct ap_device *ap_dev) 481{ 482 struct zcrypt_device *zdev = ap_dev->private; 483 484 zcrypt_device_unregister(zdev); 485} 486 487int __init zcrypt_cex2a_init(void) 488{ 489 return ap_driver_register(&zcrypt_cex2a_driver, THIS_MODULE, "cex2a"); 490} 491 492void __exit zcrypt_cex2a_exit(void) 493{ 494 ap_driver_unregister(&zcrypt_cex2a_driver); 495} 496 497module_init(zcrypt_cex2a_init); 498module_exit(zcrypt_cex2a_exit); 499