1 /* 2 * zcrypt 2.1.0 3 * 4 * Copyright IBM Corp. 2001, 2006 5 * Author(s): Robert Burroughs 6 * Eric Rossman (edrossma@us.ibm.com) 7 * 8 * Hotplug & misc device support: Jochen Roehrig (roehrig@de.ibm.com) 9 * Major cleanup & driver split: Martin Schwidefsky <schwidefsky@de.ibm.com> 10 * Ralph Wuerthner <rwuerthn@de.ibm.com> 11 * 12 * This program is free software; you can redistribute it and/or modify 13 * it under the terms of the GNU General Public License as published by 14 * the Free Software Foundation; either version 2, or (at your option) 15 * any later version. 16 * 17 * This program is distributed in the hope that it will be useful, 18 * but WITHOUT ANY WARRANTY; without even the implied warranty of 19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 20 * GNU General Public License for more details. 21 * 22 * You should have received a copy of the GNU General Public License 23 * along with this program; if not, write to the Free Software 24 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 25 */ 26 27 #include <linux/module.h> 28 #include <linux/slab.h> 29 #include <linux/init.h> 30 #include <linux/err.h> 31 #include <linux/atomic.h> 32 #include <asm/uaccess.h> 33 34 #include "ap_bus.h" 35 #include "zcrypt_api.h" 36 #include "zcrypt_error.h" 37 #include "zcrypt_cex2a.h" 38 39 #define CEX2A_MIN_MOD_SIZE 1 /* 8 bits */ 40 #define CEX2A_MAX_MOD_SIZE 256 /* 2048 bits */ 41 #define CEX3A_MIN_MOD_SIZE CEX2A_MIN_MOD_SIZE 42 #define CEX3A_MAX_MOD_SIZE 512 /* 4096 bits */ 43 44 #define CEX2A_SPEED_RATING 970 45 #define CEX3A_SPEED_RATING 900 /* Fixme: Needs finetuning */ 46 47 #define CEX2A_MAX_MESSAGE_SIZE 0x390 /* sizeof(struct type50_crb2_msg) */ 48 #define CEX2A_MAX_RESPONSE_SIZE 0x110 /* max outputdatalength + type80_hdr */ 49 50 #define CEX3A_MAX_RESPONSE_SIZE 0x210 /* 512 bit modulus 51 * (max outputdatalength) + 52 * type80_hdr*/ 53 #define CEX3A_MAX_MESSAGE_SIZE sizeof(struct type50_crb3_msg) 54 55 #define CEX2A_CLEANUP_TIME (15*HZ) 56 #define CEX3A_CLEANUP_TIME CEX2A_CLEANUP_TIME 57 58 static 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 MODULE_DEVICE_TABLE(ap, zcrypt_cex2a_ids); 65 MODULE_AUTHOR("IBM Corporation"); 66 MODULE_DESCRIPTION("CEX2A Cryptographic Coprocessor device driver, " 67 "Copyright IBM Corp. 2001, 2006"); 68 MODULE_LICENSE("GPL"); 69 70 static int zcrypt_cex2a_probe(struct ap_device *ap_dev); 71 static void zcrypt_cex2a_remove(struct ap_device *ap_dev); 72 static void zcrypt_cex2a_receive(struct ap_device *, struct ap_message *, 73 struct ap_message *); 74 75 static struct ap_driver zcrypt_cex2a_driver = { 76 .probe = zcrypt_cex2a_probe, 77 .remove = zcrypt_cex2a_remove, 78 .ids = zcrypt_cex2a_ids, 79 .request_timeout = CEX2A_CLEANUP_TIME, 80 }; 81 82 /** 83 * Convert a ICAMEX message to a type50 MEX message. 84 * 85 * @zdev: crypto device pointer 86 * @zreq: crypto request pointer 87 * @mex: pointer to user input data 88 * 89 * Returns 0 on success or -EFAULT. 90 */ 91 static int ICAMEX_msg_to_type50MEX_msg(struct zcrypt_device *zdev, 92 struct ap_message *ap_msg, 93 struct ica_rsa_modexpo *mex) 94 { 95 unsigned char *mod, *exp, *inp; 96 int mod_len; 97 98 mod_len = mex->inputdatalength; 99 100 if (mod_len <= 128) { 101 struct type50_meb1_msg *meb1 = ap_msg->message; 102 memset(meb1, 0, sizeof(*meb1)); 103 ap_msg->length = sizeof(*meb1); 104 meb1->header.msg_type_code = TYPE50_TYPE_CODE; 105 meb1->header.msg_len = sizeof(*meb1); 106 meb1->keyblock_type = TYPE50_MEB1_FMT; 107 mod = meb1->modulus + sizeof(meb1->modulus) - mod_len; 108 exp = meb1->exponent + sizeof(meb1->exponent) - mod_len; 109 inp = meb1->message + sizeof(meb1->message) - mod_len; 110 } else if (mod_len <= 256) { 111 struct type50_meb2_msg *meb2 = ap_msg->message; 112 memset(meb2, 0, sizeof(*meb2)); 113 ap_msg->length = sizeof(*meb2); 114 meb2->header.msg_type_code = TYPE50_TYPE_CODE; 115 meb2->header.msg_len = sizeof(*meb2); 116 meb2->keyblock_type = TYPE50_MEB2_FMT; 117 mod = meb2->modulus + sizeof(meb2->modulus) - mod_len; 118 exp = meb2->exponent + sizeof(meb2->exponent) - mod_len; 119 inp = meb2->message + sizeof(meb2->message) - mod_len; 120 } else { 121 /* mod_len > 256 = 4096 bit RSA Key */ 122 struct type50_meb3_msg *meb3 = ap_msg->message; 123 memset(meb3, 0, sizeof(*meb3)); 124 ap_msg->length = sizeof(*meb3); 125 meb3->header.msg_type_code = TYPE50_TYPE_CODE; 126 meb3->header.msg_len = sizeof(*meb3); 127 meb3->keyblock_type = TYPE50_MEB3_FMT; 128 mod = meb3->modulus + sizeof(meb3->modulus) - mod_len; 129 exp = meb3->exponent + sizeof(meb3->exponent) - mod_len; 130 inp = meb3->message + sizeof(meb3->message) - mod_len; 131 } 132 133 if (copy_from_user(mod, mex->n_modulus, mod_len) || 134 copy_from_user(exp, mex->b_key, mod_len) || 135 copy_from_user(inp, mex->inputdata, mod_len)) 136 return -EFAULT; 137 return 0; 138 } 139 140 /** 141 * Convert a ICACRT message to a type50 CRT message. 142 * 143 * @zdev: crypto device pointer 144 * @zreq: crypto request pointer 145 * @crt: pointer to user input data 146 * 147 * Returns 0 on success or -EFAULT. 148 */ 149 static int ICACRT_msg_to_type50CRT_msg(struct zcrypt_device *zdev, 150 struct ap_message *ap_msg, 151 struct ica_rsa_modexpo_crt *crt) 152 { 153 int mod_len, short_len, long_len, long_offset, limit; 154 unsigned char *p, *q, *dp, *dq, *u, *inp; 155 156 mod_len = crt->inputdatalength; 157 short_len = mod_len / 2; 158 long_len = mod_len / 2 + 8; 159 160 /* 161 * CEX2A cannot handle p, dp, or U > 128 bytes. 162 * If we have one of these, we need to do extra checking. 163 * For CEX3A the limit is 256 bytes. 164 */ 165 if (zdev->max_mod_size == CEX3A_MAX_MOD_SIZE) 166 limit = 256; 167 else 168 limit = 128; 169 170 if (long_len > limit) { 171 /* 172 * zcrypt_rsa_crt already checked for the leading 173 * zeroes of np_prime, bp_key and u_mult_inc. 174 */ 175 long_offset = long_len - limit; 176 long_len = limit; 177 } else 178 long_offset = 0; 179 180 /* 181 * Instead of doing extra work for p, dp, U > 64 bytes, we'll just use 182 * the larger message structure. 183 */ 184 if (long_len <= 64) { 185 struct type50_crb1_msg *crb1 = ap_msg->message; 186 memset(crb1, 0, sizeof(*crb1)); 187 ap_msg->length = sizeof(*crb1); 188 crb1->header.msg_type_code = TYPE50_TYPE_CODE; 189 crb1->header.msg_len = sizeof(*crb1); 190 crb1->keyblock_type = TYPE50_CRB1_FMT; 191 p = crb1->p + sizeof(crb1->p) - long_len; 192 q = crb1->q + sizeof(crb1->q) - short_len; 193 dp = crb1->dp + sizeof(crb1->dp) - long_len; 194 dq = crb1->dq + sizeof(crb1->dq) - short_len; 195 u = crb1->u + sizeof(crb1->u) - long_len; 196 inp = crb1->message + sizeof(crb1->message) - mod_len; 197 } else if (long_len <= 128) { 198 struct type50_crb2_msg *crb2 = ap_msg->message; 199 memset(crb2, 0, sizeof(*crb2)); 200 ap_msg->length = sizeof(*crb2); 201 crb2->header.msg_type_code = TYPE50_TYPE_CODE; 202 crb2->header.msg_len = sizeof(*crb2); 203 crb2->keyblock_type = TYPE50_CRB2_FMT; 204 p = crb2->p + sizeof(crb2->p) - long_len; 205 q = crb2->q + sizeof(crb2->q) - short_len; 206 dp = crb2->dp + sizeof(crb2->dp) - long_len; 207 dq = crb2->dq + sizeof(crb2->dq) - short_len; 208 u = crb2->u + sizeof(crb2->u) - long_len; 209 inp = crb2->message + sizeof(crb2->message) - mod_len; 210 } else { 211 /* long_len >= 256 */ 212 struct type50_crb3_msg *crb3 = ap_msg->message; 213 memset(crb3, 0, sizeof(*crb3)); 214 ap_msg->length = sizeof(*crb3); 215 crb3->header.msg_type_code = TYPE50_TYPE_CODE; 216 crb3->header.msg_len = sizeof(*crb3); 217 crb3->keyblock_type = TYPE50_CRB3_FMT; 218 p = crb3->p + sizeof(crb3->p) - long_len; 219 q = crb3->q + sizeof(crb3->q) - short_len; 220 dp = crb3->dp + sizeof(crb3->dp) - long_len; 221 dq = crb3->dq + sizeof(crb3->dq) - short_len; 222 u = crb3->u + sizeof(crb3->u) - long_len; 223 inp = crb3->message + sizeof(crb3->message) - mod_len; 224 } 225 226 if (copy_from_user(p, crt->np_prime + long_offset, long_len) || 227 copy_from_user(q, crt->nq_prime, short_len) || 228 copy_from_user(dp, crt->bp_key + long_offset, long_len) || 229 copy_from_user(dq, crt->bq_key, short_len) || 230 copy_from_user(u, crt->u_mult_inv + long_offset, long_len) || 231 copy_from_user(inp, crt->inputdata, mod_len)) 232 return -EFAULT; 233 234 return 0; 235 } 236 237 /** 238 * Copy results from a type 80 reply message back to user space. 239 * 240 * @zdev: crypto device pointer 241 * @reply: reply AP message. 242 * @data: pointer to user output data 243 * @length: size of user output data 244 * 245 * Returns 0 on success or -EFAULT. 246 */ 247 static int convert_type80(struct zcrypt_device *zdev, 248 struct ap_message *reply, 249 char __user *outputdata, 250 unsigned int outputdatalength) 251 { 252 struct type80_hdr *t80h = reply->message; 253 unsigned char *data; 254 255 if (t80h->len < sizeof(*t80h) + outputdatalength) { 256 /* The result is too short, the CEX2A card may not do that.. */ 257 zdev->online = 0; 258 return -EAGAIN; /* repeat the request on a different device. */ 259 } 260 if (zdev->user_space_type == ZCRYPT_CEX2A) 261 BUG_ON(t80h->len > CEX2A_MAX_RESPONSE_SIZE); 262 else 263 BUG_ON(t80h->len > CEX3A_MAX_RESPONSE_SIZE); 264 data = reply->message + t80h->len - outputdatalength; 265 if (copy_to_user(outputdata, data, outputdatalength)) 266 return -EFAULT; 267 return 0; 268 } 269 270 static int convert_response(struct zcrypt_device *zdev, 271 struct ap_message *reply, 272 char __user *outputdata, 273 unsigned int outputdatalength) 274 { 275 /* Response type byte is the second byte in the response. */ 276 switch (((unsigned char *) reply->message)[1]) { 277 case TYPE82_RSP_CODE: 278 case TYPE88_RSP_CODE: 279 return convert_error(zdev, reply); 280 case TYPE80_RSP_CODE: 281 return convert_type80(zdev, reply, 282 outputdata, outputdatalength); 283 default: /* Unknown response type, this should NEVER EVER happen */ 284 zdev->online = 0; 285 return -EAGAIN; /* repeat the request on a different device. */ 286 } 287 } 288 289 /** 290 * This function is called from the AP bus code after a crypto request 291 * "msg" has finished with the reply message "reply". 292 * It is called from tasklet context. 293 * @ap_dev: pointer to the AP device 294 * @msg: pointer to the AP message 295 * @reply: pointer to the AP reply message 296 */ 297 static void zcrypt_cex2a_receive(struct ap_device *ap_dev, 298 struct ap_message *msg, 299 struct ap_message *reply) 300 { 301 static struct error_hdr error_reply = { 302 .type = TYPE82_RSP_CODE, 303 .reply_code = REP82_ERROR_MACHINE_FAILURE, 304 }; 305 struct type80_hdr *t80h; 306 int length; 307 308 /* Copy the reply message to the request message buffer. */ 309 if (IS_ERR(reply)) { 310 memcpy(msg->message, &error_reply, sizeof(error_reply)); 311 goto out; 312 } 313 t80h = reply->message; 314 if (t80h->type == TYPE80_RSP_CODE) { 315 if (ap_dev->device_type == AP_DEVICE_TYPE_CEX2A) 316 length = min(CEX2A_MAX_RESPONSE_SIZE, (int) t80h->len); 317 else 318 length = min(CEX3A_MAX_RESPONSE_SIZE, (int) t80h->len); 319 memcpy(msg->message, reply->message, length); 320 } else 321 memcpy(msg->message, reply->message, sizeof error_reply); 322 out: 323 complete((struct completion *) msg->private); 324 } 325 326 static atomic_t zcrypt_step = ATOMIC_INIT(0); 327 328 /** 329 * The request distributor calls this function if it picked the CEX2A 330 * device to handle a modexpo request. 331 * @zdev: pointer to zcrypt_device structure that identifies the 332 * CEX2A device to the request distributor 333 * @mex: pointer to the modexpo request buffer 334 */ 335 static long zcrypt_cex2a_modexpo(struct zcrypt_device *zdev, 336 struct ica_rsa_modexpo *mex) 337 { 338 struct ap_message ap_msg; 339 struct completion work; 340 int rc; 341 342 ap_init_message(&ap_msg); 343 if (zdev->user_space_type == ZCRYPT_CEX2A) 344 ap_msg.message = kmalloc(CEX2A_MAX_MESSAGE_SIZE, GFP_KERNEL); 345 else 346 ap_msg.message = kmalloc(CEX3A_MAX_MESSAGE_SIZE, GFP_KERNEL); 347 if (!ap_msg.message) 348 return -ENOMEM; 349 ap_msg.receive = zcrypt_cex2a_receive; 350 ap_msg.psmid = (((unsigned long long) current->pid) << 32) + 351 atomic_inc_return(&zcrypt_step); 352 ap_msg.private = &work; 353 rc = ICAMEX_msg_to_type50MEX_msg(zdev, &ap_msg, mex); 354 if (rc) 355 goto out_free; 356 init_completion(&work); 357 ap_queue_message(zdev->ap_dev, &ap_msg); 358 rc = wait_for_completion_interruptible(&work); 359 if (rc == 0) 360 rc = convert_response(zdev, &ap_msg, mex->outputdata, 361 mex->outputdatalength); 362 else 363 /* Signal pending. */ 364 ap_cancel_message(zdev->ap_dev, &ap_msg); 365 out_free: 366 kfree(ap_msg.message); 367 return rc; 368 } 369 370 /** 371 * The request distributor calls this function if it picked the CEX2A 372 * device to handle a modexpo_crt request. 373 * @zdev: pointer to zcrypt_device structure that identifies the 374 * CEX2A device to the request distributor 375 * @crt: pointer to the modexpoc_crt request buffer 376 */ 377 static long zcrypt_cex2a_modexpo_crt(struct zcrypt_device *zdev, 378 struct ica_rsa_modexpo_crt *crt) 379 { 380 struct ap_message ap_msg; 381 struct completion work; 382 int rc; 383 384 ap_init_message(&ap_msg); 385 if (zdev->user_space_type == ZCRYPT_CEX2A) 386 ap_msg.message = kmalloc(CEX2A_MAX_MESSAGE_SIZE, GFP_KERNEL); 387 else 388 ap_msg.message = kmalloc(CEX3A_MAX_MESSAGE_SIZE, GFP_KERNEL); 389 if (!ap_msg.message) 390 return -ENOMEM; 391 ap_msg.receive = zcrypt_cex2a_receive; 392 ap_msg.psmid = (((unsigned long long) current->pid) << 32) + 393 atomic_inc_return(&zcrypt_step); 394 ap_msg.private = &work; 395 rc = ICACRT_msg_to_type50CRT_msg(zdev, &ap_msg, crt); 396 if (rc) 397 goto out_free; 398 init_completion(&work); 399 ap_queue_message(zdev->ap_dev, &ap_msg); 400 rc = wait_for_completion_interruptible(&work); 401 if (rc == 0) 402 rc = convert_response(zdev, &ap_msg, crt->outputdata, 403 crt->outputdatalength); 404 else 405 /* Signal pending. */ 406 ap_cancel_message(zdev->ap_dev, &ap_msg); 407 out_free: 408 kfree(ap_msg.message); 409 return rc; 410 } 411 412 /** 413 * The crypto operations for a CEX2A card. 414 */ 415 static struct zcrypt_ops zcrypt_cex2a_ops = { 416 .rsa_modexpo = zcrypt_cex2a_modexpo, 417 .rsa_modexpo_crt = zcrypt_cex2a_modexpo_crt, 418 }; 419 420 /** 421 * Probe function for CEX2A cards. It always accepts the AP device 422 * since the bus_match already checked the hardware type. 423 * @ap_dev: pointer to the AP device. 424 */ 425 static int zcrypt_cex2a_probe(struct ap_device *ap_dev) 426 { 427 struct zcrypt_device *zdev = NULL; 428 int rc = 0; 429 430 switch (ap_dev->device_type) { 431 case AP_DEVICE_TYPE_CEX2A: 432 zdev = zcrypt_device_alloc(CEX2A_MAX_RESPONSE_SIZE); 433 if (!zdev) 434 return -ENOMEM; 435 zdev->user_space_type = ZCRYPT_CEX2A; 436 zdev->type_string = "CEX2A"; 437 zdev->min_mod_size = CEX2A_MIN_MOD_SIZE; 438 zdev->max_mod_size = CEX2A_MAX_MOD_SIZE; 439 zdev->short_crt = 1; 440 zdev->speed_rating = CEX2A_SPEED_RATING; 441 zdev->max_exp_bit_length = CEX2A_MAX_MOD_SIZE; 442 break; 443 case AP_DEVICE_TYPE_CEX3A: 444 zdev = zcrypt_device_alloc(CEX3A_MAX_RESPONSE_SIZE); 445 if (!zdev) 446 return -ENOMEM; 447 zdev->user_space_type = ZCRYPT_CEX3A; 448 zdev->type_string = "CEX3A"; 449 zdev->min_mod_size = CEX2A_MIN_MOD_SIZE; 450 zdev->max_mod_size = CEX2A_MAX_MOD_SIZE; 451 zdev->max_exp_bit_length = CEX2A_MAX_MOD_SIZE; 452 if (ap_4096_commands_available(ap_dev->qid)) { 453 zdev->max_mod_size = CEX3A_MAX_MOD_SIZE; 454 zdev->max_exp_bit_length = CEX3A_MAX_MOD_SIZE; 455 } 456 zdev->short_crt = 1; 457 zdev->speed_rating = CEX3A_SPEED_RATING; 458 break; 459 } 460 if (zdev != NULL) { 461 zdev->ap_dev = ap_dev; 462 zdev->ops = &zcrypt_cex2a_ops; 463 zdev->online = 1; 464 ap_dev->reply = &zdev->reply; 465 ap_dev->private = zdev; 466 rc = zcrypt_device_register(zdev); 467 } 468 if (rc) { 469 ap_dev->private = NULL; 470 zcrypt_device_free(zdev); 471 } 472 return rc; 473 } 474 475 /** 476 * This is called to remove the extended CEX2A driver information 477 * if an AP device is removed. 478 */ 479 static void zcrypt_cex2a_remove(struct ap_device *ap_dev) 480 { 481 struct zcrypt_device *zdev = ap_dev->private; 482 483 zcrypt_device_unregister(zdev); 484 } 485 486 int __init zcrypt_cex2a_init(void) 487 { 488 return ap_driver_register(&zcrypt_cex2a_driver, THIS_MODULE, "cex2a"); 489 } 490 491 void __exit zcrypt_cex2a_exit(void) 492 { 493 ap_driver_unregister(&zcrypt_cex2a_driver); 494 } 495 496 module_init(zcrypt_cex2a_init); 497 module_exit(zcrypt_cex2a_exit); 498