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