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/init.h> 31 #include <linux/err.h> 32 #include <asm/atomic.h> 33 #include <asm/uaccess.h> 34 35 #include "ap_bus.h" 36 #include "zcrypt_api.h" 37 #include "zcrypt_error.h" 38 #include "zcrypt_cex2a.h" 39 40 #define CEX2A_MIN_MOD_SIZE 1 /* 8 bits */ 41 #define CEX2A_MAX_MOD_SIZE 256 /* 2048 bits */ 42 #define CEX3A_MIN_MOD_SIZE CEX2A_MIN_MOD_SIZE 43 #define CEX3A_MAX_MOD_SIZE CEX2A_MAX_MOD_SIZE 44 45 #define CEX2A_SPEED_RATING 970 46 #define CEX3A_SPEED_RATING 900 /* Fixme: Needs finetuning */ 47 48 #define CEX2A_MAX_MESSAGE_SIZE 0x390 /* sizeof(struct type50_crb2_msg) */ 49 #define CEX2A_MAX_RESPONSE_SIZE 0x110 /* max outputdatalength + type80_hdr */ 50 51 #define CEX3A_MAX_MESSAGE_SIZE CEX2A_MAX_MESSAGE_SIZE 52 #define CEX3A_MAX_RESPONSE_SIZE CEX2A_MAX_RESPONSE_SIZE 53 54 #define CEX2A_CLEANUP_TIME (15*HZ) 55 #define CEX3A_CLEANUP_TIME CEX2A_CLEANUP_TIME 56 57 static struct ap_device_id zcrypt_cex2a_ids[] = { 58 { AP_DEVICE(AP_DEVICE_TYPE_CEX2A) }, 59 { AP_DEVICE(AP_DEVICE_TYPE_CEX3A) }, 60 { /* end of list */ }, 61 }; 62 63 #ifndef CONFIG_ZCRYPT_MONOLITHIC 64 MODULE_DEVICE_TABLE(ap, zcrypt_cex2a_ids); 65 MODULE_AUTHOR("IBM Corporation"); 66 MODULE_DESCRIPTION("CEX2A Cryptographic Coprocessor device driver, " 67 "Copyright 2001, 2006 IBM Corporation"); 68 MODULE_LICENSE("GPL"); 69 #endif 70 71 static int zcrypt_cex2a_probe(struct ap_device *ap_dev); 72 static void zcrypt_cex2a_remove(struct ap_device *ap_dev); 73 static void zcrypt_cex2a_receive(struct ap_device *, struct ap_message *, 74 struct ap_message *); 75 76 static struct ap_driver zcrypt_cex2a_driver = { 77 .probe = zcrypt_cex2a_probe, 78 .remove = zcrypt_cex2a_remove, 79 .receive = zcrypt_cex2a_receive, 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 { 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 } 123 124 if (copy_from_user(mod, mex->n_modulus, mod_len) || 125 copy_from_user(exp, mex->b_key, mod_len) || 126 copy_from_user(inp, mex->inputdata, mod_len)) 127 return -EFAULT; 128 return 0; 129 } 130 131 /** 132 * Convert a ICACRT message to a type50 CRT message. 133 * 134 * @zdev: crypto device pointer 135 * @zreq: crypto request pointer 136 * @crt: pointer to user input data 137 * 138 * Returns 0 on success or -EFAULT. 139 */ 140 static int ICACRT_msg_to_type50CRT_msg(struct zcrypt_device *zdev, 141 struct ap_message *ap_msg, 142 struct ica_rsa_modexpo_crt *crt) 143 { 144 int mod_len, short_len, long_len, long_offset; 145 unsigned char *p, *q, *dp, *dq, *u, *inp; 146 147 mod_len = crt->inputdatalength; 148 short_len = mod_len / 2; 149 long_len = mod_len / 2 + 8; 150 151 /* 152 * CEX2A cannot handle p, dp, or U > 128 bytes. 153 * If we have one of these, we need to do extra checking. 154 */ 155 if (long_len > 128) { 156 /* 157 * zcrypt_rsa_crt already checked for the leading 158 * zeroes of np_prime, bp_key and u_mult_inc. 159 */ 160 long_offset = long_len - 128; 161 long_len = 128; 162 } else 163 long_offset = 0; 164 165 /* 166 * Instead of doing extra work for p, dp, U > 64 bytes, we'll just use 167 * the larger message structure. 168 */ 169 if (long_len <= 64) { 170 struct type50_crb1_msg *crb1 = ap_msg->message; 171 memset(crb1, 0, sizeof(*crb1)); 172 ap_msg->length = sizeof(*crb1); 173 crb1->header.msg_type_code = TYPE50_TYPE_CODE; 174 crb1->header.msg_len = sizeof(*crb1); 175 crb1->keyblock_type = TYPE50_CRB1_FMT; 176 p = crb1->p + sizeof(crb1->p) - long_len; 177 q = crb1->q + sizeof(crb1->q) - short_len; 178 dp = crb1->dp + sizeof(crb1->dp) - long_len; 179 dq = crb1->dq + sizeof(crb1->dq) - short_len; 180 u = crb1->u + sizeof(crb1->u) - long_len; 181 inp = crb1->message + sizeof(crb1->message) - mod_len; 182 } else { 183 struct type50_crb2_msg *crb2 = ap_msg->message; 184 memset(crb2, 0, sizeof(*crb2)); 185 ap_msg->length = sizeof(*crb2); 186 crb2->header.msg_type_code = TYPE50_TYPE_CODE; 187 crb2->header.msg_len = sizeof(*crb2); 188 crb2->keyblock_type = TYPE50_CRB2_FMT; 189 p = crb2->p + sizeof(crb2->p) - long_len; 190 q = crb2->q + sizeof(crb2->q) - short_len; 191 dp = crb2->dp + sizeof(crb2->dp) - long_len; 192 dq = crb2->dq + sizeof(crb2->dq) - short_len; 193 u = crb2->u + sizeof(crb2->u) - long_len; 194 inp = crb2->message + sizeof(crb2->message) - mod_len; 195 } 196 197 if (copy_from_user(p, crt->np_prime + long_offset, long_len) || 198 copy_from_user(q, crt->nq_prime, short_len) || 199 copy_from_user(dp, crt->bp_key + long_offset, long_len) || 200 copy_from_user(dq, crt->bq_key, short_len) || 201 copy_from_user(u, crt->u_mult_inv + long_offset, long_len) || 202 copy_from_user(inp, crt->inputdata, mod_len)) 203 return -EFAULT; 204 205 206 return 0; 207 } 208 209 /** 210 * Copy results from a type 80 reply message back to user space. 211 * 212 * @zdev: crypto device pointer 213 * @reply: reply AP message. 214 * @data: pointer to user output data 215 * @length: size of user output data 216 * 217 * Returns 0 on success or -EFAULT. 218 */ 219 static int convert_type80(struct zcrypt_device *zdev, 220 struct ap_message *reply, 221 char __user *outputdata, 222 unsigned int outputdatalength) 223 { 224 struct type80_hdr *t80h = reply->message; 225 unsigned char *data; 226 227 if (t80h->len < sizeof(*t80h) + outputdatalength) { 228 /* The result is too short, the CEX2A card may not do that.. */ 229 zdev->online = 0; 230 return -EAGAIN; /* repeat the request on a different device. */ 231 } 232 BUG_ON(t80h->len > CEX2A_MAX_RESPONSE_SIZE); 233 data = reply->message + t80h->len - outputdatalength; 234 if (copy_to_user(outputdata, data, outputdatalength)) 235 return -EFAULT; 236 return 0; 237 } 238 239 static int convert_response(struct zcrypt_device *zdev, 240 struct ap_message *reply, 241 char __user *outputdata, 242 unsigned int outputdatalength) 243 { 244 /* Response type byte is the second byte in the response. */ 245 switch (((unsigned char *) reply->message)[1]) { 246 case TYPE82_RSP_CODE: 247 case TYPE88_RSP_CODE: 248 return convert_error(zdev, reply); 249 case TYPE80_RSP_CODE: 250 return convert_type80(zdev, reply, 251 outputdata, outputdatalength); 252 default: /* Unknown response type, this should NEVER EVER happen */ 253 zdev->online = 0; 254 return -EAGAIN; /* repeat the request on a different device. */ 255 } 256 } 257 258 /** 259 * This function is called from the AP bus code after a crypto request 260 * "msg" has finished with the reply message "reply". 261 * It is called from tasklet context. 262 * @ap_dev: pointer to the AP device 263 * @msg: pointer to the AP message 264 * @reply: pointer to the AP reply message 265 */ 266 static void zcrypt_cex2a_receive(struct ap_device *ap_dev, 267 struct ap_message *msg, 268 struct ap_message *reply) 269 { 270 static struct error_hdr error_reply = { 271 .type = TYPE82_RSP_CODE, 272 .reply_code = REP82_ERROR_MACHINE_FAILURE, 273 }; 274 struct type80_hdr *t80h; 275 int length; 276 277 /* Copy the reply message to the request message buffer. */ 278 if (IS_ERR(reply)) { 279 memcpy(msg->message, &error_reply, sizeof(error_reply)); 280 goto out; 281 } 282 t80h = reply->message; 283 if (t80h->type == TYPE80_RSP_CODE) { 284 length = min(CEX2A_MAX_RESPONSE_SIZE, (int) t80h->len); 285 memcpy(msg->message, reply->message, length); 286 } else 287 memcpy(msg->message, reply->message, sizeof error_reply); 288 out: 289 complete((struct completion *) msg->private); 290 } 291 292 static atomic_t zcrypt_step = ATOMIC_INIT(0); 293 294 /** 295 * The request distributor calls this function if it picked the CEX2A 296 * device to handle a modexpo request. 297 * @zdev: pointer to zcrypt_device structure that identifies the 298 * CEX2A device to the request distributor 299 * @mex: pointer to the modexpo request buffer 300 */ 301 static long zcrypt_cex2a_modexpo(struct zcrypt_device *zdev, 302 struct ica_rsa_modexpo *mex) 303 { 304 struct ap_message ap_msg; 305 struct completion work; 306 int rc; 307 308 ap_init_message(&ap_msg); 309 ap_msg.message = kmalloc(CEX2A_MAX_MESSAGE_SIZE, GFP_KERNEL); 310 if (!ap_msg.message) 311 return -ENOMEM; 312 ap_msg.psmid = (((unsigned long long) current->pid) << 32) + 313 atomic_inc_return(&zcrypt_step); 314 ap_msg.private = &work; 315 rc = ICAMEX_msg_to_type50MEX_msg(zdev, &ap_msg, mex); 316 if (rc) 317 goto out_free; 318 init_completion(&work); 319 ap_queue_message(zdev->ap_dev, &ap_msg); 320 rc = wait_for_completion_interruptible(&work); 321 if (rc == 0) 322 rc = convert_response(zdev, &ap_msg, mex->outputdata, 323 mex->outputdatalength); 324 else 325 /* Signal pending. */ 326 ap_cancel_message(zdev->ap_dev, &ap_msg); 327 out_free: 328 kfree(ap_msg.message); 329 return rc; 330 } 331 332 /** 333 * The request distributor calls this function if it picked the CEX2A 334 * device to handle a modexpo_crt request. 335 * @zdev: pointer to zcrypt_device structure that identifies the 336 * CEX2A device to the request distributor 337 * @crt: pointer to the modexpoc_crt request buffer 338 */ 339 static long zcrypt_cex2a_modexpo_crt(struct zcrypt_device *zdev, 340 struct ica_rsa_modexpo_crt *crt) 341 { 342 struct ap_message ap_msg; 343 struct completion work; 344 int rc; 345 346 ap_init_message(&ap_msg); 347 ap_msg.message = kmalloc(CEX2A_MAX_MESSAGE_SIZE, GFP_KERNEL); 348 if (!ap_msg.message) 349 return -ENOMEM; 350 ap_msg.psmid = (((unsigned long long) current->pid) << 32) + 351 atomic_inc_return(&zcrypt_step); 352 ap_msg.private = &work; 353 rc = ICACRT_msg_to_type50CRT_msg(zdev, &ap_msg, crt); 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, crt->outputdata, 361 crt->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 crypto operations for a CEX2A card. 372 */ 373 static struct zcrypt_ops zcrypt_cex2a_ops = { 374 .rsa_modexpo = zcrypt_cex2a_modexpo, 375 .rsa_modexpo_crt = zcrypt_cex2a_modexpo_crt, 376 }; 377 378 /** 379 * Probe function for CEX2A cards. It always accepts the AP device 380 * since the bus_match already checked the hardware type. 381 * @ap_dev: pointer to the AP device. 382 */ 383 static int zcrypt_cex2a_probe(struct ap_device *ap_dev) 384 { 385 struct zcrypt_device *zdev = NULL; 386 int rc = 0; 387 388 switch (ap_dev->device_type) { 389 case AP_DEVICE_TYPE_CEX2A: 390 zdev = zcrypt_device_alloc(CEX2A_MAX_RESPONSE_SIZE); 391 if (!zdev) 392 return -ENOMEM; 393 zdev->user_space_type = ZCRYPT_CEX2A; 394 zdev->type_string = "CEX2A"; 395 zdev->min_mod_size = CEX2A_MIN_MOD_SIZE; 396 zdev->max_mod_size = CEX2A_MAX_MOD_SIZE; 397 zdev->short_crt = 1; 398 zdev->speed_rating = CEX2A_SPEED_RATING; 399 break; 400 case AP_DEVICE_TYPE_CEX3A: 401 zdev = zcrypt_device_alloc(CEX3A_MAX_RESPONSE_SIZE); 402 if (!zdev) 403 return -ENOMEM; 404 zdev->user_space_type = ZCRYPT_CEX3A; 405 zdev->type_string = "CEX3A"; 406 zdev->min_mod_size = CEX3A_MIN_MOD_SIZE; 407 zdev->max_mod_size = CEX3A_MAX_MOD_SIZE; 408 zdev->short_crt = 1; 409 zdev->speed_rating = CEX3A_SPEED_RATING; 410 break; 411 } 412 if (zdev != NULL) { 413 zdev->ap_dev = ap_dev; 414 zdev->ops = &zcrypt_cex2a_ops; 415 zdev->online = 1; 416 ap_dev->reply = &zdev->reply; 417 ap_dev->private = zdev; 418 rc = zcrypt_device_register(zdev); 419 } 420 if (rc) { 421 ap_dev->private = NULL; 422 zcrypt_device_free(zdev); 423 } 424 return rc; 425 } 426 427 /** 428 * This is called to remove the extended CEX2A driver information 429 * if an AP device is removed. 430 */ 431 static void zcrypt_cex2a_remove(struct ap_device *ap_dev) 432 { 433 struct zcrypt_device *zdev = ap_dev->private; 434 435 zcrypt_device_unregister(zdev); 436 } 437 438 int __init zcrypt_cex2a_init(void) 439 { 440 return ap_driver_register(&zcrypt_cex2a_driver, THIS_MODULE, "cex2a"); 441 } 442 443 void __exit zcrypt_cex2a_exit(void) 444 { 445 ap_driver_unregister(&zcrypt_cex2a_driver); 446 } 447 448 #ifndef CONFIG_ZCRYPT_MONOLITHIC 449 module_init(zcrypt_cex2a_init); 450 module_exit(zcrypt_cex2a_exit); 451 #endif 452