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 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 #ifndef CONFIG_ZCRYPT_MONOLITHIC 67 MODULE_DEVICE_TABLE(ap, zcrypt_cex2a_ids); 68 MODULE_AUTHOR("IBM Corporation"); 69 MODULE_DESCRIPTION("CEX2A Cryptographic Coprocessor device driver, " 70 "Copyright 2001, 2006 IBM Corporation"); 71 MODULE_LICENSE("GPL"); 72 #endif 73 74 static int zcrypt_cex2a_probe(struct ap_device *ap_dev); 75 static void zcrypt_cex2a_remove(struct ap_device *ap_dev); 76 static void zcrypt_cex2a_receive(struct ap_device *, struct ap_message *, 77 struct ap_message *); 78 79 static struct ap_driver zcrypt_cex2a_driver = { 80 .probe = zcrypt_cex2a_probe, 81 .remove = zcrypt_cex2a_remove, 82 .receive = zcrypt_cex2a_receive, 83 .ids = zcrypt_cex2a_ids, 84 .request_timeout = CEX2A_CLEANUP_TIME, 85 }; 86 87 /** 88 * Convert a ICAMEX message to a type50 MEX message. 89 * 90 * @zdev: crypto device pointer 91 * @zreq: crypto request pointer 92 * @mex: pointer to user input data 93 * 94 * Returns 0 on success or -EFAULT. 95 */ 96 static int ICAMEX_msg_to_type50MEX_msg(struct zcrypt_device *zdev, 97 struct ap_message *ap_msg, 98 struct ica_rsa_modexpo *mex) 99 { 100 unsigned char *mod, *exp, *inp; 101 int mod_len; 102 103 mod_len = mex->inputdatalength; 104 105 if (mod_len <= 128) { 106 struct type50_meb1_msg *meb1 = ap_msg->message; 107 memset(meb1, 0, sizeof(*meb1)); 108 ap_msg->length = sizeof(*meb1); 109 meb1->header.msg_type_code = TYPE50_TYPE_CODE; 110 meb1->header.msg_len = sizeof(*meb1); 111 meb1->keyblock_type = TYPE50_MEB1_FMT; 112 mod = meb1->modulus + sizeof(meb1->modulus) - mod_len; 113 exp = meb1->exponent + sizeof(meb1->exponent) - mod_len; 114 inp = meb1->message + sizeof(meb1->message) - mod_len; 115 } else if (mod_len <= 256) { 116 struct type50_meb2_msg *meb2 = ap_msg->message; 117 memset(meb2, 0, sizeof(*meb2)); 118 ap_msg->length = sizeof(*meb2); 119 meb2->header.msg_type_code = TYPE50_TYPE_CODE; 120 meb2->header.msg_len = sizeof(*meb2); 121 meb2->keyblock_type = TYPE50_MEB2_FMT; 122 mod = meb2->modulus + sizeof(meb2->modulus) - mod_len; 123 exp = meb2->exponent + sizeof(meb2->exponent) - mod_len; 124 inp = meb2->message + sizeof(meb2->message) - mod_len; 125 } else { 126 /* mod_len > 256 = 4096 bit RSA Key */ 127 struct type50_meb3_msg *meb3 = ap_msg->message; 128 memset(meb3, 0, sizeof(*meb3)); 129 ap_msg->length = sizeof(*meb3); 130 meb3->header.msg_type_code = TYPE50_TYPE_CODE; 131 meb3->header.msg_len = sizeof(*meb3); 132 meb3->keyblock_type = TYPE50_MEB3_FMT; 133 mod = meb3->modulus + sizeof(meb3->modulus) - mod_len; 134 exp = meb3->exponent + sizeof(meb3->exponent) - mod_len; 135 inp = meb3->message + sizeof(meb3->message) - mod_len; 136 } 137 138 if (copy_from_user(mod, mex->n_modulus, mod_len) || 139 copy_from_user(exp, mex->b_key, mod_len) || 140 copy_from_user(inp, mex->inputdata, mod_len)) 141 return -EFAULT; 142 return 0; 143 } 144 145 /** 146 * Convert a ICACRT message to a type50 CRT message. 147 * 148 * @zdev: crypto device pointer 149 * @zreq: crypto request pointer 150 * @crt: pointer to user input data 151 * 152 * Returns 0 on success or -EFAULT. 153 */ 154 static int ICACRT_msg_to_type50CRT_msg(struct zcrypt_device *zdev, 155 struct ap_message *ap_msg, 156 struct ica_rsa_modexpo_crt *crt) 157 { 158 int mod_len, short_len, long_len, long_offset, limit; 159 unsigned char *p, *q, *dp, *dq, *u, *inp; 160 161 mod_len = crt->inputdatalength; 162 short_len = mod_len / 2; 163 long_len = mod_len / 2 + 8; 164 165 /* 166 * CEX2A cannot handle p, dp, or U > 128 bytes. 167 * If we have one of these, we need to do extra checking. 168 * For CEX3A the limit is 256 bytes. 169 */ 170 if (zdev->max_mod_size == CEX3A_MAX_MOD_SIZE) 171 limit = 256; 172 else 173 limit = 128; 174 175 if (long_len > limit) { 176 /* 177 * zcrypt_rsa_crt already checked for the leading 178 * zeroes of np_prime, bp_key and u_mult_inc. 179 */ 180 long_offset = long_len - limit; 181 long_len = limit; 182 } else 183 long_offset = 0; 184 185 /* 186 * Instead of doing extra work for p, dp, U > 64 bytes, we'll just use 187 * the larger message structure. 188 */ 189 if (long_len <= 64) { 190 struct type50_crb1_msg *crb1 = ap_msg->message; 191 memset(crb1, 0, sizeof(*crb1)); 192 ap_msg->length = sizeof(*crb1); 193 crb1->header.msg_type_code = TYPE50_TYPE_CODE; 194 crb1->header.msg_len = sizeof(*crb1); 195 crb1->keyblock_type = TYPE50_CRB1_FMT; 196 p = crb1->p + sizeof(crb1->p) - long_len; 197 q = crb1->q + sizeof(crb1->q) - short_len; 198 dp = crb1->dp + sizeof(crb1->dp) - long_len; 199 dq = crb1->dq + sizeof(crb1->dq) - short_len; 200 u = crb1->u + sizeof(crb1->u) - long_len; 201 inp = crb1->message + sizeof(crb1->message) - mod_len; 202 } else if (long_len <= 128) { 203 struct type50_crb2_msg *crb2 = ap_msg->message; 204 memset(crb2, 0, sizeof(*crb2)); 205 ap_msg->length = sizeof(*crb2); 206 crb2->header.msg_type_code = TYPE50_TYPE_CODE; 207 crb2->header.msg_len = sizeof(*crb2); 208 crb2->keyblock_type = TYPE50_CRB2_FMT; 209 p = crb2->p + sizeof(crb2->p) - long_len; 210 q = crb2->q + sizeof(crb2->q) - short_len; 211 dp = crb2->dp + sizeof(crb2->dp) - long_len; 212 dq = crb2->dq + sizeof(crb2->dq) - short_len; 213 u = crb2->u + sizeof(crb2->u) - long_len; 214 inp = crb2->message + sizeof(crb2->message) - mod_len; 215 } else { 216 /* long_len >= 256 */ 217 struct type50_crb3_msg *crb3 = ap_msg->message; 218 memset(crb3, 0, sizeof(*crb3)); 219 ap_msg->length = sizeof(*crb3); 220 crb3->header.msg_type_code = TYPE50_TYPE_CODE; 221 crb3->header.msg_len = sizeof(*crb3); 222 crb3->keyblock_type = TYPE50_CRB3_FMT; 223 p = crb3->p + sizeof(crb3->p) - long_len; 224 q = crb3->q + sizeof(crb3->q) - short_len; 225 dp = crb3->dp + sizeof(crb3->dp) - long_len; 226 dq = crb3->dq + sizeof(crb3->dq) - short_len; 227 u = crb3->u + sizeof(crb3->u) - long_len; 228 inp = crb3->message + sizeof(crb3->message) - mod_len; 229 } 230 231 if (copy_from_user(p, crt->np_prime + long_offset, long_len) || 232 copy_from_user(q, crt->nq_prime, short_len) || 233 copy_from_user(dp, crt->bp_key + long_offset, long_len) || 234 copy_from_user(dq, crt->bq_key, short_len) || 235 copy_from_user(u, crt->u_mult_inv + long_offset, long_len) || 236 copy_from_user(inp, crt->inputdata, mod_len)) 237 return -EFAULT; 238 239 return 0; 240 } 241 242 /** 243 * Copy results from a type 80 reply message back to user space. 244 * 245 * @zdev: crypto device pointer 246 * @reply: reply AP message. 247 * @data: pointer to user output data 248 * @length: size of user output data 249 * 250 * Returns 0 on success or -EFAULT. 251 */ 252 static int convert_type80(struct zcrypt_device *zdev, 253 struct ap_message *reply, 254 char __user *outputdata, 255 unsigned int outputdatalength) 256 { 257 struct type80_hdr *t80h = reply->message; 258 unsigned char *data; 259 260 if (t80h->len < sizeof(*t80h) + outputdatalength) { 261 /* The result is too short, the CEX2A card may not do that.. */ 262 zdev->online = 0; 263 return -EAGAIN; /* repeat the request on a different device. */ 264 } 265 if (zdev->user_space_type == ZCRYPT_CEX2A) 266 BUG_ON(t80h->len > CEX2A_MAX_RESPONSE_SIZE); 267 else 268 BUG_ON(t80h->len > CEX3A_MAX_RESPONSE_SIZE); 269 data = reply->message + t80h->len - outputdatalength; 270 if (copy_to_user(outputdata, data, outputdatalength)) 271 return -EFAULT; 272 return 0; 273 } 274 275 static int convert_response(struct zcrypt_device *zdev, 276 struct ap_message *reply, 277 char __user *outputdata, 278 unsigned int outputdatalength) 279 { 280 /* Response type byte is the second byte in the response. */ 281 switch (((unsigned char *) reply->message)[1]) { 282 case TYPE82_RSP_CODE: 283 case TYPE88_RSP_CODE: 284 return convert_error(zdev, reply); 285 case TYPE80_RSP_CODE: 286 return convert_type80(zdev, reply, 287 outputdata, outputdatalength); 288 default: /* Unknown response type, this should NEVER EVER happen */ 289 zdev->online = 0; 290 return -EAGAIN; /* repeat the request on a different device. */ 291 } 292 } 293 294 /** 295 * This function is called from the AP bus code after a crypto request 296 * "msg" has finished with the reply message "reply". 297 * It is called from tasklet context. 298 * @ap_dev: pointer to the AP device 299 * @msg: pointer to the AP message 300 * @reply: pointer to the AP reply message 301 */ 302 static void zcrypt_cex2a_receive(struct ap_device *ap_dev, 303 struct ap_message *msg, 304 struct ap_message *reply) 305 { 306 static struct error_hdr error_reply = { 307 .type = TYPE82_RSP_CODE, 308 .reply_code = REP82_ERROR_MACHINE_FAILURE, 309 }; 310 struct type80_hdr *t80h; 311 int length; 312 313 /* Copy the reply message to the request message buffer. */ 314 if (IS_ERR(reply)) { 315 memcpy(msg->message, &error_reply, sizeof(error_reply)); 316 goto out; 317 } 318 t80h = reply->message; 319 if (t80h->type == TYPE80_RSP_CODE) { 320 if (ap_dev->device_type == AP_DEVICE_TYPE_CEX2A) 321 length = min(CEX2A_MAX_RESPONSE_SIZE, (int) t80h->len); 322 else 323 length = min(CEX3A_MAX_RESPONSE_SIZE, (int) t80h->len); 324 memcpy(msg->message, reply->message, length); 325 } else 326 memcpy(msg->message, reply->message, sizeof error_reply); 327 out: 328 complete((struct completion *) msg->private); 329 } 330 331 static atomic_t zcrypt_step = ATOMIC_INIT(0); 332 333 /** 334 * The request distributor calls this function if it picked the CEX2A 335 * device to handle a modexpo request. 336 * @zdev: pointer to zcrypt_device structure that identifies the 337 * CEX2A device to the request distributor 338 * @mex: pointer to the modexpo request buffer 339 */ 340 static long zcrypt_cex2a_modexpo(struct zcrypt_device *zdev, 341 struct ica_rsa_modexpo *mex) 342 { 343 struct ap_message ap_msg; 344 struct completion work; 345 int rc; 346 347 ap_init_message(&ap_msg); 348 if (zdev->user_space_type == ZCRYPT_CEX2A) 349 ap_msg.message = kmalloc(CEX2A_MAX_MESSAGE_SIZE, GFP_KERNEL); 350 else 351 ap_msg.message = kmalloc(CEX3A_MAX_MESSAGE_SIZE, GFP_KERNEL); 352 if (!ap_msg.message) 353 return -ENOMEM; 354 ap_msg.psmid = (((unsigned long long) current->pid) << 32) + 355 atomic_inc_return(&zcrypt_step); 356 ap_msg.private = &work; 357 rc = ICAMEX_msg_to_type50MEX_msg(zdev, &ap_msg, mex); 358 if (rc) 359 goto out_free; 360 init_completion(&work); 361 ap_queue_message(zdev->ap_dev, &ap_msg); 362 rc = wait_for_completion_interruptible(&work); 363 if (rc == 0) 364 rc = convert_response(zdev, &ap_msg, mex->outputdata, 365 mex->outputdatalength); 366 else 367 /* Signal pending. */ 368 ap_cancel_message(zdev->ap_dev, &ap_msg); 369 out_free: 370 kfree(ap_msg.message); 371 return rc; 372 } 373 374 /** 375 * The request distributor calls this function if it picked the CEX2A 376 * device to handle a modexpo_crt request. 377 * @zdev: pointer to zcrypt_device structure that identifies the 378 * CEX2A device to the request distributor 379 * @crt: pointer to the modexpoc_crt request buffer 380 */ 381 static long zcrypt_cex2a_modexpo_crt(struct zcrypt_device *zdev, 382 struct ica_rsa_modexpo_crt *crt) 383 { 384 struct ap_message ap_msg; 385 struct completion work; 386 int rc; 387 388 ap_init_message(&ap_msg); 389 if (zdev->user_space_type == ZCRYPT_CEX2A) 390 ap_msg.message = kmalloc(CEX2A_MAX_MESSAGE_SIZE, GFP_KERNEL); 391 else 392 ap_msg.message = kmalloc(CEX3A_MAX_MESSAGE_SIZE, GFP_KERNEL); 393 if (!ap_msg.message) 394 return -ENOMEM; 395 ap_msg.psmid = (((unsigned long long) current->pid) << 32) + 396 atomic_inc_return(&zcrypt_step); 397 ap_msg.private = &work; 398 rc = ICACRT_msg_to_type50CRT_msg(zdev, &ap_msg, crt); 399 if (rc) 400 goto out_free; 401 init_completion(&work); 402 ap_queue_message(zdev->ap_dev, &ap_msg); 403 rc = wait_for_completion_interruptible(&work); 404 if (rc == 0) 405 rc = convert_response(zdev, &ap_msg, crt->outputdata, 406 crt->outputdatalength); 407 else 408 /* Signal pending. */ 409 ap_cancel_message(zdev->ap_dev, &ap_msg); 410 out_free: 411 kfree(ap_msg.message); 412 return rc; 413 } 414 415 /** 416 * The crypto operations for a CEX2A card. 417 */ 418 static struct zcrypt_ops zcrypt_cex2a_ops = { 419 .rsa_modexpo = zcrypt_cex2a_modexpo, 420 .rsa_modexpo_crt = zcrypt_cex2a_modexpo_crt, 421 }; 422 423 /** 424 * Probe function for CEX2A cards. It always accepts the AP device 425 * since the bus_match already checked the hardware type. 426 * @ap_dev: pointer to the AP device. 427 */ 428 static int zcrypt_cex2a_probe(struct ap_device *ap_dev) 429 { 430 struct zcrypt_device *zdev = NULL; 431 int rc = 0; 432 433 switch (ap_dev->device_type) { 434 case AP_DEVICE_TYPE_CEX2A: 435 zdev = zcrypt_device_alloc(CEX2A_MAX_RESPONSE_SIZE); 436 if (!zdev) 437 return -ENOMEM; 438 zdev->user_space_type = ZCRYPT_CEX2A; 439 zdev->type_string = "CEX2A"; 440 zdev->min_mod_size = CEX2A_MIN_MOD_SIZE; 441 zdev->max_mod_size = CEX2A_MAX_MOD_SIZE; 442 zdev->short_crt = 1; 443 zdev->speed_rating = CEX2A_SPEED_RATING; 444 zdev->max_exp_bit_length = CEX2A_MAX_MOD_SIZE; 445 break; 446 case AP_DEVICE_TYPE_CEX3A: 447 zdev = zcrypt_device_alloc(CEX3A_MAX_RESPONSE_SIZE); 448 if (!zdev) 449 return -ENOMEM; 450 zdev->user_space_type = ZCRYPT_CEX3A; 451 zdev->type_string = "CEX3A"; 452 zdev->min_mod_size = CEX2A_MIN_MOD_SIZE; 453 zdev->max_mod_size = CEX2A_MAX_MOD_SIZE; 454 zdev->max_exp_bit_length = CEX2A_MAX_MOD_SIZE; 455 if (ap_4096_commands_available(ap_dev->qid)) { 456 zdev->max_mod_size = CEX3A_MAX_MOD_SIZE; 457 zdev->max_exp_bit_length = CEX3A_MAX_MOD_SIZE; 458 } 459 zdev->short_crt = 1; 460 zdev->speed_rating = CEX3A_SPEED_RATING; 461 break; 462 } 463 if (zdev != NULL) { 464 zdev->ap_dev = ap_dev; 465 zdev->ops = &zcrypt_cex2a_ops; 466 zdev->online = 1; 467 ap_dev->reply = &zdev->reply; 468 ap_dev->private = zdev; 469 rc = zcrypt_device_register(zdev); 470 } 471 if (rc) { 472 ap_dev->private = NULL; 473 zcrypt_device_free(zdev); 474 } 475 return rc; 476 } 477 478 /** 479 * This is called to remove the extended CEX2A driver information 480 * if an AP device is removed. 481 */ 482 static void zcrypt_cex2a_remove(struct ap_device *ap_dev) 483 { 484 struct zcrypt_device *zdev = ap_dev->private; 485 486 zcrypt_device_unregister(zdev); 487 } 488 489 int __init zcrypt_cex2a_init(void) 490 { 491 return ap_driver_register(&zcrypt_cex2a_driver, THIS_MODULE, "cex2a"); 492 } 493 494 void __exit zcrypt_cex2a_exit(void) 495 { 496 ap_driver_unregister(&zcrypt_cex2a_driver); 497 } 498 499 #ifndef CONFIG_ZCRYPT_MONOLITHIC 500 module_init(zcrypt_cex2a_init); 501 module_exit(zcrypt_cex2a_exit); 502 #endif 503