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 60 static 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 66 MODULE_DEVICE_TABLE(ap, zcrypt_cex2a_ids); 67 MODULE_AUTHOR("IBM Corporation"); 68 MODULE_DESCRIPTION("CEX2A Cryptographic Coprocessor device driver, " 69 "Copyright 2001, 2006 IBM Corporation"); 70 MODULE_LICENSE("GPL"); 71 72 static int zcrypt_cex2a_probe(struct ap_device *ap_dev); 73 static void zcrypt_cex2a_remove(struct ap_device *ap_dev); 74 static void zcrypt_cex2a_receive(struct ap_device *, struct ap_message *, 75 struct ap_message *); 76 77 static struct ap_driver zcrypt_cex2a_driver = { 78 .probe = zcrypt_cex2a_probe, 79 .remove = zcrypt_cex2a_remove, 80 .ids = zcrypt_cex2a_ids, 81 .request_timeout = CEX2A_CLEANUP_TIME, 82 }; 83 84 /** 85 * Convert a ICAMEX message to a type50 MEX message. 86 * 87 * @zdev: crypto device pointer 88 * @zreq: crypto request pointer 89 * @mex: pointer to user input data 90 * 91 * Returns 0 on success or -EFAULT. 92 */ 93 static int ICAMEX_msg_to_type50MEX_msg(struct zcrypt_device *zdev, 94 struct ap_message *ap_msg, 95 struct ica_rsa_modexpo *mex) 96 { 97 unsigned char *mod, *exp, *inp; 98 int mod_len; 99 100 mod_len = mex->inputdatalength; 101 102 if (mod_len <= 128) { 103 struct type50_meb1_msg *meb1 = ap_msg->message; 104 memset(meb1, 0, sizeof(*meb1)); 105 ap_msg->length = sizeof(*meb1); 106 meb1->header.msg_type_code = TYPE50_TYPE_CODE; 107 meb1->header.msg_len = sizeof(*meb1); 108 meb1->keyblock_type = TYPE50_MEB1_FMT; 109 mod = meb1->modulus + sizeof(meb1->modulus) - mod_len; 110 exp = meb1->exponent + sizeof(meb1->exponent) - mod_len; 111 inp = meb1->message + sizeof(meb1->message) - mod_len; 112 } else if (mod_len <= 256) { 113 struct type50_meb2_msg *meb2 = ap_msg->message; 114 memset(meb2, 0, sizeof(*meb2)); 115 ap_msg->length = sizeof(*meb2); 116 meb2->header.msg_type_code = TYPE50_TYPE_CODE; 117 meb2->header.msg_len = sizeof(*meb2); 118 meb2->keyblock_type = TYPE50_MEB2_FMT; 119 mod = meb2->modulus + sizeof(meb2->modulus) - mod_len; 120 exp = meb2->exponent + sizeof(meb2->exponent) - mod_len; 121 inp = meb2->message + sizeof(meb2->message) - mod_len; 122 } else { 123 /* mod_len > 256 = 4096 bit RSA Key */ 124 struct type50_meb3_msg *meb3 = ap_msg->message; 125 memset(meb3, 0, sizeof(*meb3)); 126 ap_msg->length = sizeof(*meb3); 127 meb3->header.msg_type_code = TYPE50_TYPE_CODE; 128 meb3->header.msg_len = sizeof(*meb3); 129 meb3->keyblock_type = TYPE50_MEB3_FMT; 130 mod = meb3->modulus + sizeof(meb3->modulus) - mod_len; 131 exp = meb3->exponent + sizeof(meb3->exponent) - mod_len; 132 inp = meb3->message + sizeof(meb3->message) - mod_len; 133 } 134 135 if (copy_from_user(mod, mex->n_modulus, mod_len) || 136 copy_from_user(exp, mex->b_key, mod_len) || 137 copy_from_user(inp, mex->inputdata, mod_len)) 138 return -EFAULT; 139 return 0; 140 } 141 142 /** 143 * Convert a ICACRT message to a type50 CRT message. 144 * 145 * @zdev: crypto device pointer 146 * @zreq: crypto request pointer 147 * @crt: pointer to user input data 148 * 149 * Returns 0 on success or -EFAULT. 150 */ 151 static int ICACRT_msg_to_type50CRT_msg(struct zcrypt_device *zdev, 152 struct ap_message *ap_msg, 153 struct ica_rsa_modexpo_crt *crt) 154 { 155 int mod_len, short_len, long_len, long_offset, limit; 156 unsigned char *p, *q, *dp, *dq, *u, *inp; 157 158 mod_len = crt->inputdatalength; 159 short_len = mod_len / 2; 160 long_len = mod_len / 2 + 8; 161 162 /* 163 * CEX2A cannot handle p, dp, or U > 128 bytes. 164 * If we have one of these, we need to do extra checking. 165 * For CEX3A the limit is 256 bytes. 166 */ 167 if (zdev->max_mod_size == CEX3A_MAX_MOD_SIZE) 168 limit = 256; 169 else 170 limit = 128; 171 172 if (long_len > limit) { 173 /* 174 * zcrypt_rsa_crt already checked for the leading 175 * zeroes of np_prime, bp_key and u_mult_inc. 176 */ 177 long_offset = long_len - limit; 178 long_len = limit; 179 } else 180 long_offset = 0; 181 182 /* 183 * Instead of doing extra work for p, dp, U > 64 bytes, we'll just use 184 * the larger message structure. 185 */ 186 if (long_len <= 64) { 187 struct type50_crb1_msg *crb1 = ap_msg->message; 188 memset(crb1, 0, sizeof(*crb1)); 189 ap_msg->length = sizeof(*crb1); 190 crb1->header.msg_type_code = TYPE50_TYPE_CODE; 191 crb1->header.msg_len = sizeof(*crb1); 192 crb1->keyblock_type = TYPE50_CRB1_FMT; 193 p = crb1->p + sizeof(crb1->p) - long_len; 194 q = crb1->q + sizeof(crb1->q) - short_len; 195 dp = crb1->dp + sizeof(crb1->dp) - long_len; 196 dq = crb1->dq + sizeof(crb1->dq) - short_len; 197 u = crb1->u + sizeof(crb1->u) - long_len; 198 inp = crb1->message + sizeof(crb1->message) - mod_len; 199 } else if (long_len <= 128) { 200 struct type50_crb2_msg *crb2 = ap_msg->message; 201 memset(crb2, 0, sizeof(*crb2)); 202 ap_msg->length = sizeof(*crb2); 203 crb2->header.msg_type_code = TYPE50_TYPE_CODE; 204 crb2->header.msg_len = sizeof(*crb2); 205 crb2->keyblock_type = TYPE50_CRB2_FMT; 206 p = crb2->p + sizeof(crb2->p) - long_len; 207 q = crb2->q + sizeof(crb2->q) - short_len; 208 dp = crb2->dp + sizeof(crb2->dp) - long_len; 209 dq = crb2->dq + sizeof(crb2->dq) - short_len; 210 u = crb2->u + sizeof(crb2->u) - long_len; 211 inp = crb2->message + sizeof(crb2->message) - mod_len; 212 } else { 213 /* long_len >= 256 */ 214 struct type50_crb3_msg *crb3 = ap_msg->message; 215 memset(crb3, 0, sizeof(*crb3)); 216 ap_msg->length = sizeof(*crb3); 217 crb3->header.msg_type_code = TYPE50_TYPE_CODE; 218 crb3->header.msg_len = sizeof(*crb3); 219 crb3->keyblock_type = TYPE50_CRB3_FMT; 220 p = crb3->p + sizeof(crb3->p) - long_len; 221 q = crb3->q + sizeof(crb3->q) - short_len; 222 dp = crb3->dp + sizeof(crb3->dp) - long_len; 223 dq = crb3->dq + sizeof(crb3->dq) - short_len; 224 u = crb3->u + sizeof(crb3->u) - long_len; 225 inp = crb3->message + sizeof(crb3->message) - mod_len; 226 } 227 228 if (copy_from_user(p, crt->np_prime + long_offset, long_len) || 229 copy_from_user(q, crt->nq_prime, short_len) || 230 copy_from_user(dp, crt->bp_key + long_offset, long_len) || 231 copy_from_user(dq, crt->bq_key, short_len) || 232 copy_from_user(u, crt->u_mult_inv + long_offset, long_len) || 233 copy_from_user(inp, crt->inputdata, mod_len)) 234 return -EFAULT; 235 236 return 0; 237 } 238 239 /** 240 * Copy results from a type 80 reply message back to user space. 241 * 242 * @zdev: crypto device pointer 243 * @reply: reply AP message. 244 * @data: pointer to user output data 245 * @length: size of user output data 246 * 247 * Returns 0 on success or -EFAULT. 248 */ 249 static int convert_type80(struct zcrypt_device *zdev, 250 struct ap_message *reply, 251 char __user *outputdata, 252 unsigned int outputdatalength) 253 { 254 struct type80_hdr *t80h = reply->message; 255 unsigned char *data; 256 257 if (t80h->len < sizeof(*t80h) + outputdatalength) { 258 /* The result is too short, the CEX2A card may not do that.. */ 259 zdev->online = 0; 260 return -EAGAIN; /* repeat the request on a different device. */ 261 } 262 if (zdev->user_space_type == ZCRYPT_CEX2A) 263 BUG_ON(t80h->len > CEX2A_MAX_RESPONSE_SIZE); 264 else 265 BUG_ON(t80h->len > CEX3A_MAX_RESPONSE_SIZE); 266 data = reply->message + t80h->len - outputdatalength; 267 if (copy_to_user(outputdata, data, outputdatalength)) 268 return -EFAULT; 269 return 0; 270 } 271 272 static int convert_response(struct zcrypt_device *zdev, 273 struct ap_message *reply, 274 char __user *outputdata, 275 unsigned int outputdatalength) 276 { 277 /* Response type byte is the second byte in the response. */ 278 switch (((unsigned char *) reply->message)[1]) { 279 case TYPE82_RSP_CODE: 280 case TYPE88_RSP_CODE: 281 return convert_error(zdev, reply); 282 case TYPE80_RSP_CODE: 283 return convert_type80(zdev, reply, 284 outputdata, outputdatalength); 285 default: /* Unknown response type, this should NEVER EVER happen */ 286 zdev->online = 0; 287 return -EAGAIN; /* repeat the request on a different device. */ 288 } 289 } 290 291 /** 292 * This function is called from the AP bus code after a crypto request 293 * "msg" has finished with the reply message "reply". 294 * It is called from tasklet context. 295 * @ap_dev: pointer to the AP device 296 * @msg: pointer to the AP message 297 * @reply: pointer to the AP reply message 298 */ 299 static void zcrypt_cex2a_receive(struct ap_device *ap_dev, 300 struct ap_message *msg, 301 struct ap_message *reply) 302 { 303 static struct error_hdr error_reply = { 304 .type = TYPE82_RSP_CODE, 305 .reply_code = REP82_ERROR_MACHINE_FAILURE, 306 }; 307 struct type80_hdr *t80h; 308 int length; 309 310 /* Copy the reply message to the request message buffer. */ 311 if (IS_ERR(reply)) { 312 memcpy(msg->message, &error_reply, sizeof(error_reply)); 313 goto out; 314 } 315 t80h = reply->message; 316 if (t80h->type == TYPE80_RSP_CODE) { 317 if (ap_dev->device_type == AP_DEVICE_TYPE_CEX2A) 318 length = min(CEX2A_MAX_RESPONSE_SIZE, (int) t80h->len); 319 else 320 length = min(CEX3A_MAX_RESPONSE_SIZE, (int) t80h->len); 321 memcpy(msg->message, reply->message, length); 322 } else 323 memcpy(msg->message, reply->message, sizeof error_reply); 324 out: 325 complete((struct completion *) msg->private); 326 } 327 328 static atomic_t zcrypt_step = ATOMIC_INIT(0); 329 330 /** 331 * The request distributor calls this function if it picked the CEX2A 332 * device to handle a modexpo request. 333 * @zdev: pointer to zcrypt_device structure that identifies the 334 * CEX2A device to the request distributor 335 * @mex: pointer to the modexpo request buffer 336 */ 337 static long zcrypt_cex2a_modexpo(struct zcrypt_device *zdev, 338 struct ica_rsa_modexpo *mex) 339 { 340 struct ap_message ap_msg; 341 struct completion work; 342 int rc; 343 344 ap_init_message(&ap_msg); 345 if (zdev->user_space_type == ZCRYPT_CEX2A) 346 ap_msg.message = kmalloc(CEX2A_MAX_MESSAGE_SIZE, GFP_KERNEL); 347 else 348 ap_msg.message = kmalloc(CEX3A_MAX_MESSAGE_SIZE, GFP_KERNEL); 349 if (!ap_msg.message) 350 return -ENOMEM; 351 ap_msg.receive = zcrypt_cex2a_receive; 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); 367 out_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 */ 379 static 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.receive = zcrypt_cex2a_receive; 394 ap_msg.psmid = (((unsigned long long) current->pid) << 32) + 395 atomic_inc_return(&zcrypt_step); 396 ap_msg.private = &work; 397 rc = ICACRT_msg_to_type50CRT_msg(zdev, &ap_msg, crt); 398 if (rc) 399 goto out_free; 400 init_completion(&work); 401 ap_queue_message(zdev->ap_dev, &ap_msg); 402 rc = wait_for_completion_interruptible(&work); 403 if (rc == 0) 404 rc = convert_response(zdev, &ap_msg, crt->outputdata, 405 crt->outputdatalength); 406 else 407 /* Signal pending. */ 408 ap_cancel_message(zdev->ap_dev, &ap_msg); 409 out_free: 410 kfree(ap_msg.message); 411 return rc; 412 } 413 414 /** 415 * The crypto operations for a CEX2A card. 416 */ 417 static struct zcrypt_ops zcrypt_cex2a_ops = { 418 .rsa_modexpo = zcrypt_cex2a_modexpo, 419 .rsa_modexpo_crt = zcrypt_cex2a_modexpo_crt, 420 }; 421 422 /** 423 * Probe function for CEX2A cards. It always accepts the AP device 424 * since the bus_match already checked the hardware type. 425 * @ap_dev: pointer to the AP device. 426 */ 427 static int zcrypt_cex2a_probe(struct ap_device *ap_dev) 428 { 429 struct zcrypt_device *zdev = NULL; 430 int rc = 0; 431 432 switch (ap_dev->device_type) { 433 case AP_DEVICE_TYPE_CEX2A: 434 zdev = zcrypt_device_alloc(CEX2A_MAX_RESPONSE_SIZE); 435 if (!zdev) 436 return -ENOMEM; 437 zdev->user_space_type = ZCRYPT_CEX2A; 438 zdev->type_string = "CEX2A"; 439 zdev->min_mod_size = CEX2A_MIN_MOD_SIZE; 440 zdev->max_mod_size = CEX2A_MAX_MOD_SIZE; 441 zdev->short_crt = 1; 442 zdev->speed_rating = CEX2A_SPEED_RATING; 443 zdev->max_exp_bit_length = CEX2A_MAX_MOD_SIZE; 444 break; 445 case AP_DEVICE_TYPE_CEX3A: 446 zdev = zcrypt_device_alloc(CEX3A_MAX_RESPONSE_SIZE); 447 if (!zdev) 448 return -ENOMEM; 449 zdev->user_space_type = ZCRYPT_CEX3A; 450 zdev->type_string = "CEX3A"; 451 zdev->min_mod_size = CEX2A_MIN_MOD_SIZE; 452 zdev->max_mod_size = CEX2A_MAX_MOD_SIZE; 453 zdev->max_exp_bit_length = CEX2A_MAX_MOD_SIZE; 454 if (ap_4096_commands_available(ap_dev->qid)) { 455 zdev->max_mod_size = CEX3A_MAX_MOD_SIZE; 456 zdev->max_exp_bit_length = CEX3A_MAX_MOD_SIZE; 457 } 458 zdev->short_crt = 1; 459 zdev->speed_rating = CEX3A_SPEED_RATING; 460 break; 461 } 462 if (zdev != NULL) { 463 zdev->ap_dev = ap_dev; 464 zdev->ops = &zcrypt_cex2a_ops; 465 zdev->online = 1; 466 ap_dev->reply = &zdev->reply; 467 ap_dev->private = zdev; 468 rc = zcrypt_device_register(zdev); 469 } 470 if (rc) { 471 ap_dev->private = NULL; 472 zcrypt_device_free(zdev); 473 } 474 return rc; 475 } 476 477 /** 478 * This is called to remove the extended CEX2A driver information 479 * if an AP device is removed. 480 */ 481 static void zcrypt_cex2a_remove(struct ap_device *ap_dev) 482 { 483 struct zcrypt_device *zdev = ap_dev->private; 484 485 zcrypt_device_unregister(zdev); 486 } 487 488 int __init zcrypt_cex2a_init(void) 489 { 490 return ap_driver_register(&zcrypt_cex2a_driver, THIS_MODULE, "cex2a"); 491 } 492 493 void __exit zcrypt_cex2a_exit(void) 494 { 495 ap_driver_unregister(&zcrypt_cex2a_driver); 496 } 497 498 module_init(zcrypt_cex2a_init); 499 module_exit(zcrypt_cex2a_exit); 500