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 43#define CEX2A_SPEED_RATING 970 44 45#define CEX2A_MAX_MESSAGE_SIZE 0x390 /* sizeof(struct type50_crb2_msg) */ 46#define CEX2A_MAX_RESPONSE_SIZE 0x110 /* max outputdatalength + type80_hdr */ 47 48#define CEX2A_CLEANUP_TIME (15*HZ) 49 50static struct ap_device_id zcrypt_cex2a_ids[] = { 51 { AP_DEVICE(AP_DEVICE_TYPE_CEX2A) }, 52 { /* end of list */ }, 53}; 54 55#ifndef CONFIG_ZCRYPT_MONOLITHIC 56MODULE_DEVICE_TABLE(ap, zcrypt_cex2a_ids); 57MODULE_AUTHOR("IBM Corporation"); 58MODULE_DESCRIPTION("CEX2A Cryptographic Coprocessor device driver, " 59 "Copyright 2001, 2006 IBM Corporation"); 60MODULE_LICENSE("GPL"); 61#endif 62 63static int zcrypt_cex2a_probe(struct ap_device *ap_dev); 64static void zcrypt_cex2a_remove(struct ap_device *ap_dev); 65static void zcrypt_cex2a_receive(struct ap_device *, struct ap_message *, 66 struct ap_message *); 67 68static struct ap_driver zcrypt_cex2a_driver = { 69 .probe = zcrypt_cex2a_probe, 70 .remove = zcrypt_cex2a_remove, 71 .receive = zcrypt_cex2a_receive, 72 .ids = zcrypt_cex2a_ids, 73}; 74 75/** 76 * Convert a ICAMEX message to a type50 MEX message. 77 * 78 * @zdev: crypto device pointer 79 * @zreq: crypto request pointer 80 * @mex: pointer to user input data 81 * 82 * Returns 0 on success or -EFAULT. 83 */ 84static int ICAMEX_msg_to_type50MEX_msg(struct zcrypt_device *zdev, 85 struct ap_message *ap_msg, 86 struct ica_rsa_modexpo *mex) 87{ 88 unsigned char *mod, *exp, *inp; 89 int mod_len; 90 91 mod_len = mex->inputdatalength; 92 93 if (mod_len <= 128) { 94 struct type50_meb1_msg *meb1 = ap_msg->message; 95 memset(meb1, 0, sizeof(*meb1)); 96 ap_msg->length = sizeof(*meb1); 97 meb1->header.msg_type_code = TYPE50_TYPE_CODE; 98 meb1->header.msg_len = sizeof(*meb1); 99 meb1->keyblock_type = TYPE50_MEB1_FMT; 100 mod = meb1->modulus + sizeof(meb1->modulus) - mod_len; 101 exp = meb1->exponent + sizeof(meb1->exponent) - mod_len; 102 inp = meb1->message + sizeof(meb1->message) - mod_len; 103 } else { 104 struct type50_meb2_msg *meb2 = ap_msg->message; 105 memset(meb2, 0, sizeof(*meb2)); 106 ap_msg->length = sizeof(*meb2); 107 meb2->header.msg_type_code = TYPE50_TYPE_CODE; 108 meb2->header.msg_len = sizeof(*meb2); 109 meb2->keyblock_type = TYPE50_MEB2_FMT; 110 mod = meb2->modulus + sizeof(meb2->modulus) - mod_len; 111 exp = meb2->exponent + sizeof(meb2->exponent) - mod_len; 112 inp = meb2->message + sizeof(meb2->message) - mod_len; 113 } 114 115 if (copy_from_user(mod, mex->n_modulus, mod_len) || 116 copy_from_user(exp, mex->b_key, mod_len) || 117 copy_from_user(inp, mex->inputdata, mod_len)) 118 return -EFAULT; 119 return 0; 120} 121 122/** 123 * Convert a ICACRT message to a type50 CRT message. 124 * 125 * @zdev: crypto device pointer 126 * @zreq: crypto request pointer 127 * @crt: pointer to user input data 128 * 129 * Returns 0 on success or -EFAULT. 130 */ 131static int ICACRT_msg_to_type50CRT_msg(struct zcrypt_device *zdev, 132 struct ap_message *ap_msg, 133 struct ica_rsa_modexpo_crt *crt) 134{ 135 int mod_len, short_len, long_len, long_offset; 136 unsigned char *p, *q, *dp, *dq, *u, *inp; 137 138 mod_len = crt->inputdatalength; 139 short_len = mod_len / 2; 140 long_len = mod_len / 2 + 8; 141 142 /* 143 * CEX2A cannot handle p, dp, or U > 128 bytes. 144 * If we have one of these, we need to do extra checking. 145 */ 146 if (long_len > 128) { 147 /* 148 * zcrypt_rsa_crt already checked for the leading 149 * zeroes of np_prime, bp_key and u_mult_inc. 150 */ 151 long_offset = long_len - 128; 152 long_len = 128; 153 } else 154 long_offset = 0; 155 156 /* 157 * Instead of doing extra work for p, dp, U > 64 bytes, we'll just use 158 * the larger message structure. 159 */ 160 if (long_len <= 64) { 161 struct type50_crb1_msg *crb1 = ap_msg->message; 162 memset(crb1, 0, sizeof(*crb1)); 163 ap_msg->length = sizeof(*crb1); 164 crb1->header.msg_type_code = TYPE50_TYPE_CODE; 165 crb1->header.msg_len = sizeof(*crb1); 166 crb1->keyblock_type = TYPE50_CRB1_FMT; 167 p = crb1->p + sizeof(crb1->p) - long_len; 168 q = crb1->q + sizeof(crb1->q) - short_len; 169 dp = crb1->dp + sizeof(crb1->dp) - long_len; 170 dq = crb1->dq + sizeof(crb1->dq) - short_len; 171 u = crb1->u + sizeof(crb1->u) - long_len; 172 inp = crb1->message + sizeof(crb1->message) - mod_len; 173 } else { 174 struct type50_crb2_msg *crb2 = ap_msg->message; 175 memset(crb2, 0, sizeof(*crb2)); 176 ap_msg->length = sizeof(*crb2); 177 crb2->header.msg_type_code = TYPE50_TYPE_CODE; 178 crb2->header.msg_len = sizeof(*crb2); 179 crb2->keyblock_type = TYPE50_CRB2_FMT; 180 p = crb2->p + sizeof(crb2->p) - long_len; 181 q = crb2->q + sizeof(crb2->q) - short_len; 182 dp = crb2->dp + sizeof(crb2->dp) - long_len; 183 dq = crb2->dq + sizeof(crb2->dq) - short_len; 184 u = crb2->u + sizeof(crb2->u) - long_len; 185 inp = crb2->message + sizeof(crb2->message) - mod_len; 186 } 187 188 if (copy_from_user(p, crt->np_prime + long_offset, long_len) || 189 copy_from_user(q, crt->nq_prime, short_len) || 190 copy_from_user(dp, crt->bp_key + long_offset, long_len) || 191 copy_from_user(dq, crt->bq_key, short_len) || 192 copy_from_user(u, crt->u_mult_inv + long_offset, long_len) || 193 copy_from_user(inp, crt->inputdata, mod_len)) 194 return -EFAULT; 195 196 197 return 0; 198} 199 200/** 201 * Copy results from a type 80 reply message back to user space. 202 * 203 * @zdev: crypto device pointer 204 * @reply: reply AP message. 205 * @data: pointer to user output data 206 * @length: size of user output data 207 * 208 * Returns 0 on success or -EFAULT. 209 */ 210static int convert_type80(struct zcrypt_device *zdev, 211 struct ap_message *reply, 212 char __user *outputdata, 213 unsigned int outputdatalength) 214{ 215 struct type80_hdr *t80h = reply->message; 216 unsigned char *data; 217 218 if (t80h->len < sizeof(*t80h) + outputdatalength) { 219 /* The result is too short, the CEX2A card may not do that.. */ 220 zdev->online = 0; 221 return -EAGAIN; /* repeat the request on a different device. */ 222 } 223 BUG_ON(t80h->len > CEX2A_MAX_RESPONSE_SIZE); 224 data = reply->message + t80h->len - outputdatalength; 225 if (copy_to_user(outputdata, data, outputdatalength)) 226 return -EFAULT; 227 return 0; 228} 229 230static int convert_response(struct zcrypt_device *zdev, 231 struct ap_message *reply, 232 char __user *outputdata, 233 unsigned int outputdatalength) 234{ 235 /* Response type byte is the second byte in the response. */ 236 switch (((unsigned char *) reply->message)[1]) { 237 case TYPE82_RSP_CODE: 238 case TYPE88_RSP_CODE: 239 return convert_error(zdev, reply); 240 case TYPE80_RSP_CODE: 241 return convert_type80(zdev, reply, 242 outputdata, outputdatalength); 243 default: /* Unknown response type, this should NEVER EVER happen */ 244 PRINTK("Unrecognized Message Header: %08x%08x\n", 245 *(unsigned int *) reply->message, 246 *(unsigned int *) (reply->message+4)); 247 zdev->online = 0; 248 return -EAGAIN; /* repeat the request on a different device. */ 249 } 250} 251 252/** 253 * This function is called from the AP bus code after a crypto request 254 * "msg" has finished with the reply message "reply". 255 * It is called from tasklet context. 256 * @ap_dev: pointer to the AP device 257 * @msg: pointer to the AP message 258 * @reply: pointer to the AP reply message 259 */ 260static void zcrypt_cex2a_receive(struct ap_device *ap_dev, 261 struct ap_message *msg, 262 struct ap_message *reply) 263{ 264 static struct error_hdr error_reply = { 265 .type = TYPE82_RSP_CODE, 266 .reply_code = REP82_ERROR_MACHINE_FAILURE, 267 }; 268 struct type80_hdr *t80h = reply->message; 269 int length; 270 271 /* Copy the reply message to the request message buffer. */ 272 if (IS_ERR(reply)) 273 memcpy(msg->message, &error_reply, sizeof(error_reply)); 274 else if (t80h->type == TYPE80_RSP_CODE) { 275 length = min(CEX2A_MAX_RESPONSE_SIZE, (int) t80h->len); 276 memcpy(msg->message, reply->message, length); 277 } else 278 memcpy(msg->message, reply->message, sizeof error_reply); 279 complete((struct completion *) msg->private); 280} 281 282static atomic_t zcrypt_step = ATOMIC_INIT(0); 283 284/** 285 * The request distributor calls this function if it picked the CEX2A 286 * device to handle a modexpo request. 287 * @zdev: pointer to zcrypt_device structure that identifies the 288 * CEX2A device to the request distributor 289 * @mex: pointer to the modexpo request buffer 290 */ 291static long zcrypt_cex2a_modexpo(struct zcrypt_device *zdev, 292 struct ica_rsa_modexpo *mex) 293{ 294 struct ap_message ap_msg; 295 struct completion work; 296 int rc; 297 298 ap_msg.message = kmalloc(CEX2A_MAX_MESSAGE_SIZE, GFP_KERNEL); 299 if (!ap_msg.message) 300 return -ENOMEM; 301 ap_msg.psmid = (((unsigned long long) current->pid) << 32) + 302 atomic_inc_return(&zcrypt_step); 303 ap_msg.private = &work; 304 rc = ICAMEX_msg_to_type50MEX_msg(zdev, &ap_msg, mex); 305 if (rc) 306 goto out_free; 307 init_completion(&work); 308 ap_queue_message(zdev->ap_dev, &ap_msg); 309 rc = wait_for_completion_interruptible_timeout( 310 &work, CEX2A_CLEANUP_TIME); 311 if (rc > 0) 312 rc = convert_response(zdev, &ap_msg, mex->outputdata, 313 mex->outputdatalength); 314 else { 315 /* Signal pending or message timed out. */ 316 ap_cancel_message(zdev->ap_dev, &ap_msg); 317 if (rc == 0) 318 /* Message timed out. */ 319 rc = -ETIME; 320 } 321out_free: 322 kfree(ap_msg.message); 323 return rc; 324} 325 326/** 327 * The request distributor calls this function if it picked the CEX2A 328 * device to handle a modexpo_crt request. 329 * @zdev: pointer to zcrypt_device structure that identifies the 330 * CEX2A device to the request distributor 331 * @crt: pointer to the modexpoc_crt request buffer 332 */ 333static long zcrypt_cex2a_modexpo_crt(struct zcrypt_device *zdev, 334 struct ica_rsa_modexpo_crt *crt) 335{ 336 struct ap_message ap_msg; 337 struct completion work; 338 int rc; 339 340 ap_msg.message = kmalloc(CEX2A_MAX_MESSAGE_SIZE, GFP_KERNEL); 341 if (!ap_msg.message) 342 return -ENOMEM; 343 ap_msg.psmid = (((unsigned long long) current->pid) << 32) + 344 atomic_inc_return(&zcrypt_step); 345 ap_msg.private = &work; 346 rc = ICACRT_msg_to_type50CRT_msg(zdev, &ap_msg, crt); 347 if (rc) 348 goto out_free; 349 init_completion(&work); 350 ap_queue_message(zdev->ap_dev, &ap_msg); 351 rc = wait_for_completion_interruptible_timeout( 352 &work, CEX2A_CLEANUP_TIME); 353 if (rc > 0) 354 rc = convert_response(zdev, &ap_msg, crt->outputdata, 355 crt->outputdatalength); 356 else { 357 /* Signal pending or message timed out. */ 358 ap_cancel_message(zdev->ap_dev, &ap_msg); 359 if (rc == 0) 360 /* Message timed out. */ 361 rc = -ETIME; 362 } 363out_free: 364 kfree(ap_msg.message); 365 return rc; 366} 367 368/** 369 * The crypto operations for a CEX2A card. 370 */ 371static struct zcrypt_ops zcrypt_cex2a_ops = { 372 .rsa_modexpo = zcrypt_cex2a_modexpo, 373 .rsa_modexpo_crt = zcrypt_cex2a_modexpo_crt, 374}; 375 376/** 377 * Probe function for CEX2A cards. It always accepts the AP device 378 * since the bus_match already checked the hardware type. 379 * @ap_dev: pointer to the AP device. 380 */ 381static int zcrypt_cex2a_probe(struct ap_device *ap_dev) 382{ 383 struct zcrypt_device *zdev; 384 int rc; 385 386 zdev = zcrypt_device_alloc(CEX2A_MAX_RESPONSE_SIZE); 387 if (!zdev) 388 return -ENOMEM; 389 zdev->ap_dev = ap_dev; 390 zdev->ops = &zcrypt_cex2a_ops; 391 zdev->online = 1; 392 zdev->user_space_type = ZCRYPT_CEX2A; 393 zdev->type_string = "CEX2A"; 394 zdev->min_mod_size = CEX2A_MIN_MOD_SIZE; 395 zdev->max_mod_size = CEX2A_MAX_MOD_SIZE; 396 zdev->short_crt = 1; 397 zdev->speed_rating = CEX2A_SPEED_RATING; 398 ap_dev->reply = &zdev->reply; 399 ap_dev->private = zdev; 400 rc = zcrypt_device_register(zdev); 401 if (rc) 402 goto out_free; 403 return 0; 404 405out_free: 406 ap_dev->private = NULL; 407 zcrypt_device_free(zdev); 408 return rc; 409} 410 411/** 412 * This is called to remove the extended CEX2A driver information 413 * if an AP device is removed. 414 */ 415static void zcrypt_cex2a_remove(struct ap_device *ap_dev) 416{ 417 struct zcrypt_device *zdev = ap_dev->private; 418 419 zcrypt_device_unregister(zdev); 420} 421 422int __init zcrypt_cex2a_init(void) 423{ 424 return ap_driver_register(&zcrypt_cex2a_driver, THIS_MODULE, "cex2a"); 425} 426 427void __exit zcrypt_cex2a_exit(void) 428{ 429 ap_driver_unregister(&zcrypt_cex2a_driver); 430} 431 432#ifndef CONFIG_ZCRYPT_MONOLITHIC 433module_init(zcrypt_cex2a_init); 434module_exit(zcrypt_cex2a_exit); 435#endif 436