1 /*
2 * linux/drivers/s390/crypto/zcrypt_pcica.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 <linux/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_pcica.h"
40
41 #define PCICA_MIN_MOD_SIZE 1 /* 8 bits */
42 #define PCICA_MAX_MOD_SIZE 256 /* 2048 bits */
43
44 #define PCICA_SPEED_RATING 2800
45
46 #define PCICA_MAX_MESSAGE_SIZE 0x3a0 /* sizeof(struct type4_lcr) */
47 #define PCICA_MAX_RESPONSE_SIZE 0x110 /* max outputdatalength + type80_hdr */
48
49 #define PCICA_CLEANUP_TIME (15*HZ)
50
51 static struct ap_device_id zcrypt_pcica_ids[] = {
52 { AP_DEVICE(AP_DEVICE_TYPE_PCICA) },
53 { /* end of list */ },
54 };
55
56 MODULE_DEVICE_TABLE(ap, zcrypt_pcica_ids);
57 MODULE_AUTHOR("IBM Corporation");
58 MODULE_DESCRIPTION("PCICA Cryptographic Coprocessor device driver, "
59 "Copyright 2001, 2006 IBM Corporation");
60 MODULE_LICENSE("GPL");
61
62 static int zcrypt_pcica_probe(struct ap_device *ap_dev);
63 static void zcrypt_pcica_remove(struct ap_device *ap_dev);
64 static void zcrypt_pcica_receive(struct ap_device *, struct ap_message *,
65 struct ap_message *);
66
67 static struct ap_driver zcrypt_pcica_driver = {
68 .probe = zcrypt_pcica_probe,
69 .remove = zcrypt_pcica_remove,
70 .receive = zcrypt_pcica_receive,
71 .ids = zcrypt_pcica_ids,
72 .request_timeout = PCICA_CLEANUP_TIME,
73 };
74
75 /**
76 * Convert a ICAMEX message to a type4 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 */
ICAMEX_msg_to_type4MEX_msg(struct zcrypt_device * zdev,struct ap_message * ap_msg,struct ica_rsa_modexpo * mex)84 static int ICAMEX_msg_to_type4MEX_msg(struct zcrypt_device *zdev,
85 struct ap_message *ap_msg,
86 struct ica_rsa_modexpo *mex)
87 {
88 unsigned char *modulus, *exponent, *message;
89 int mod_len;
90
91 mod_len = mex->inputdatalength;
92
93 if (mod_len <= 128) {
94 struct type4_sme *sme = ap_msg->message;
95 memset(sme, 0, sizeof(*sme));
96 ap_msg->length = sizeof(*sme);
97 sme->header.msg_fmt = TYPE4_SME_FMT;
98 sme->header.msg_len = sizeof(*sme);
99 sme->header.msg_type_code = TYPE4_TYPE_CODE;
100 sme->header.request_code = TYPE4_REQU_CODE;
101 modulus = sme->modulus + sizeof(sme->modulus) - mod_len;
102 exponent = sme->exponent + sizeof(sme->exponent) - mod_len;
103 message = sme->message + sizeof(sme->message) - mod_len;
104 } else {
105 struct type4_lme *lme = ap_msg->message;
106 memset(lme, 0, sizeof(*lme));
107 ap_msg->length = sizeof(*lme);
108 lme->header.msg_fmt = TYPE4_LME_FMT;
109 lme->header.msg_len = sizeof(*lme);
110 lme->header.msg_type_code = TYPE4_TYPE_CODE;
111 lme->header.request_code = TYPE4_REQU_CODE;
112 modulus = lme->modulus + sizeof(lme->modulus) - mod_len;
113 exponent = lme->exponent + sizeof(lme->exponent) - mod_len;
114 message = lme->message + sizeof(lme->message) - mod_len;
115 }
116
117 if (copy_from_user(modulus, mex->n_modulus, mod_len) ||
118 copy_from_user(exponent, mex->b_key, mod_len) ||
119 copy_from_user(message, mex->inputdata, mod_len))
120 return -EFAULT;
121 return 0;
122 }
123
124 /**
125 * Convert a ICACRT message to a type4 CRT message.
126 *
127 * @zdev: crypto device pointer
128 * @zreq: crypto request pointer
129 * @crt: pointer to user input data
130 *
131 * Returns 0 on success or -EFAULT.
132 */
ICACRT_msg_to_type4CRT_msg(struct zcrypt_device * zdev,struct ap_message * ap_msg,struct ica_rsa_modexpo_crt * crt)133 static int ICACRT_msg_to_type4CRT_msg(struct zcrypt_device *zdev,
134 struct ap_message *ap_msg,
135 struct ica_rsa_modexpo_crt *crt)
136 {
137 unsigned char *p, *q, *dp, *dq, *u, *inp;
138 int mod_len, short_len, long_len;
139
140 mod_len = crt->inputdatalength;
141 short_len = mod_len / 2;
142 long_len = mod_len / 2 + 8;
143
144 if (mod_len <= 128) {
145 struct type4_scr *scr = ap_msg->message;
146 memset(scr, 0, sizeof(*scr));
147 ap_msg->length = sizeof(*scr);
148 scr->header.msg_type_code = TYPE4_TYPE_CODE;
149 scr->header.request_code = TYPE4_REQU_CODE;
150 scr->header.msg_fmt = TYPE4_SCR_FMT;
151 scr->header.msg_len = sizeof(*scr);
152 p = scr->p + sizeof(scr->p) - long_len;
153 q = scr->q + sizeof(scr->q) - short_len;
154 dp = scr->dp + sizeof(scr->dp) - long_len;
155 dq = scr->dq + sizeof(scr->dq) - short_len;
156 u = scr->u + sizeof(scr->u) - long_len;
157 inp = scr->message + sizeof(scr->message) - mod_len;
158 } else {
159 struct type4_lcr *lcr = ap_msg->message;
160 memset(lcr, 0, sizeof(*lcr));
161 ap_msg->length = sizeof(*lcr);
162 lcr->header.msg_type_code = TYPE4_TYPE_CODE;
163 lcr->header.request_code = TYPE4_REQU_CODE;
164 lcr->header.msg_fmt = TYPE4_LCR_FMT;
165 lcr->header.msg_len = sizeof(*lcr);
166 p = lcr->p + sizeof(lcr->p) - long_len;
167 q = lcr->q + sizeof(lcr->q) - short_len;
168 dp = lcr->dp + sizeof(lcr->dp) - long_len;
169 dq = lcr->dq + sizeof(lcr->dq) - short_len;
170 u = lcr->u + sizeof(lcr->u) - long_len;
171 inp = lcr->message + sizeof(lcr->message) - mod_len;
172 }
173
174 if (copy_from_user(p, crt->np_prime, long_len) ||
175 copy_from_user(q, crt->nq_prime, short_len) ||
176 copy_from_user(dp, crt->bp_key, long_len) ||
177 copy_from_user(dq, crt->bq_key, short_len) ||
178 copy_from_user(u, crt->u_mult_inv, long_len) ||
179 copy_from_user(inp, crt->inputdata, mod_len))
180 return -EFAULT;
181 return 0;
182 }
183
184 /**
185 * Copy results from a type 84 reply message back to user space.
186 *
187 * @zdev: crypto device pointer
188 * @reply: reply AP message.
189 * @data: pointer to user output data
190 * @length: size of user output data
191 *
192 * Returns 0 on success or -EFAULT.
193 */
convert_type84(struct zcrypt_device * zdev,struct ap_message * reply,char __user * outputdata,unsigned int outputdatalength)194 static int convert_type84(struct zcrypt_device *zdev,
195 struct ap_message *reply,
196 char __user *outputdata,
197 unsigned int outputdatalength)
198 {
199 struct type84_hdr *t84h = reply->message;
200 char *data;
201
202 if (t84h->len < sizeof(*t84h) + outputdatalength) {
203 /* The result is too short, the PCICA card may not do that.. */
204 zdev->online = 0;
205 return -EAGAIN; /* repeat the request on a different device. */
206 }
207 BUG_ON(t84h->len > PCICA_MAX_RESPONSE_SIZE);
208 data = reply->message + t84h->len - outputdatalength;
209 if (copy_to_user(outputdata, data, outputdatalength))
210 return -EFAULT;
211 return 0;
212 }
213
convert_response(struct zcrypt_device * zdev,struct ap_message * reply,char __user * outputdata,unsigned int outputdatalength)214 static int convert_response(struct zcrypt_device *zdev,
215 struct ap_message *reply,
216 char __user *outputdata,
217 unsigned int outputdatalength)
218 {
219 /* Response type byte is the second byte in the response. */
220 switch (((unsigned char *) reply->message)[1]) {
221 case TYPE82_RSP_CODE:
222 case TYPE88_RSP_CODE:
223 return convert_error(zdev, reply);
224 case TYPE84_RSP_CODE:
225 return convert_type84(zdev, reply,
226 outputdata, outputdatalength);
227 default: /* Unknown response type, this should NEVER EVER happen */
228 zdev->online = 0;
229 return -EAGAIN; /* repeat the request on a different device. */
230 }
231 }
232
233 /**
234 * This function is called from the AP bus code after a crypto request
235 * "msg" has finished with the reply message "reply".
236 * It is called from tasklet context.
237 * @ap_dev: pointer to the AP device
238 * @msg: pointer to the AP message
239 * @reply: pointer to the AP reply message
240 */
zcrypt_pcica_receive(struct ap_device * ap_dev,struct ap_message * msg,struct ap_message * reply)241 static void zcrypt_pcica_receive(struct ap_device *ap_dev,
242 struct ap_message *msg,
243 struct ap_message *reply)
244 {
245 static struct error_hdr error_reply = {
246 .type = TYPE82_RSP_CODE,
247 .reply_code = REP82_ERROR_MACHINE_FAILURE,
248 };
249 struct type84_hdr *t84h;
250 int length;
251
252 /* Copy the reply message to the request message buffer. */
253 if (IS_ERR(reply)) {
254 memcpy(msg->message, &error_reply, sizeof(error_reply));
255 goto out;
256 }
257 t84h = reply->message;
258 if (t84h->code == TYPE84_RSP_CODE) {
259 length = min(PCICA_MAX_RESPONSE_SIZE, (int) t84h->len);
260 memcpy(msg->message, reply->message, length);
261 } else
262 memcpy(msg->message, reply->message, sizeof error_reply);
263 out:
264 complete((struct completion *) msg->private);
265 }
266
267 static atomic_t zcrypt_step = ATOMIC_INIT(0);
268
269 /**
270 * The request distributor calls this function if it picked the PCICA
271 * device to handle a modexpo request.
272 * @zdev: pointer to zcrypt_device structure that identifies the
273 * PCICA device to the request distributor
274 * @mex: pointer to the modexpo request buffer
275 */
zcrypt_pcica_modexpo(struct zcrypt_device * zdev,struct ica_rsa_modexpo * mex)276 static long zcrypt_pcica_modexpo(struct zcrypt_device *zdev,
277 struct ica_rsa_modexpo *mex)
278 {
279 struct ap_message ap_msg;
280 struct completion work;
281 int rc;
282
283 ap_init_message(&ap_msg);
284 ap_msg.message = kmalloc(PCICA_MAX_MESSAGE_SIZE, GFP_KERNEL);
285 if (!ap_msg.message)
286 return -ENOMEM;
287 ap_msg.psmid = (((unsigned long long) current->pid) << 32) +
288 atomic_inc_return(&zcrypt_step);
289 ap_msg.private = &work;
290 rc = ICAMEX_msg_to_type4MEX_msg(zdev, &ap_msg, mex);
291 if (rc)
292 goto out_free;
293 init_completion(&work);
294 ap_queue_message(zdev->ap_dev, &ap_msg);
295 rc = wait_for_completion_interruptible(&work);
296 if (rc == 0)
297 rc = convert_response(zdev, &ap_msg, mex->outputdata,
298 mex->outputdatalength);
299 else
300 /* Signal pending. */
301 ap_cancel_message(zdev->ap_dev, &ap_msg);
302 out_free:
303 kfree(ap_msg.message);
304 return rc;
305 }
306
307 /**
308 * The request distributor calls this function if it picked the PCICA
309 * device to handle a modexpo_crt request.
310 * @zdev: pointer to zcrypt_device structure that identifies the
311 * PCICA device to the request distributor
312 * @crt: pointer to the modexpoc_crt request buffer
313 */
zcrypt_pcica_modexpo_crt(struct zcrypt_device * zdev,struct ica_rsa_modexpo_crt * crt)314 static long zcrypt_pcica_modexpo_crt(struct zcrypt_device *zdev,
315 struct ica_rsa_modexpo_crt *crt)
316 {
317 struct ap_message ap_msg;
318 struct completion work;
319 int rc;
320
321 ap_init_message(&ap_msg);
322 ap_msg.message = kmalloc(PCICA_MAX_MESSAGE_SIZE, GFP_KERNEL);
323 if (!ap_msg.message)
324 return -ENOMEM;
325 ap_msg.psmid = (((unsigned long long) current->pid) << 32) +
326 atomic_inc_return(&zcrypt_step);
327 ap_msg.private = &work;
328 rc = ICACRT_msg_to_type4CRT_msg(zdev, &ap_msg, crt);
329 if (rc)
330 goto out_free;
331 init_completion(&work);
332 ap_queue_message(zdev->ap_dev, &ap_msg);
333 rc = wait_for_completion_interruptible(&work);
334 if (rc == 0)
335 rc = convert_response(zdev, &ap_msg, crt->outputdata,
336 crt->outputdatalength);
337 else
338 /* Signal pending. */
339 ap_cancel_message(zdev->ap_dev, &ap_msg);
340 out_free:
341 kfree(ap_msg.message);
342 return rc;
343 }
344
345 /**
346 * The crypto operations for a PCICA card.
347 */
348 static struct zcrypt_ops zcrypt_pcica_ops = {
349 .rsa_modexpo = zcrypt_pcica_modexpo,
350 .rsa_modexpo_crt = zcrypt_pcica_modexpo_crt,
351 };
352
353 /**
354 * Probe function for PCICA cards. It always accepts the AP device
355 * since the bus_match already checked the hardware type.
356 * @ap_dev: pointer to the AP device.
357 */
zcrypt_pcica_probe(struct ap_device * ap_dev)358 static int zcrypt_pcica_probe(struct ap_device *ap_dev)
359 {
360 struct zcrypt_device *zdev;
361 int rc;
362
363 zdev = zcrypt_device_alloc(PCICA_MAX_RESPONSE_SIZE);
364 if (!zdev)
365 return -ENOMEM;
366 zdev->ap_dev = ap_dev;
367 zdev->ops = &zcrypt_pcica_ops;
368 zdev->online = 1;
369 zdev->user_space_type = ZCRYPT_PCICA;
370 zdev->type_string = "PCICA";
371 zdev->min_mod_size = PCICA_MIN_MOD_SIZE;
372 zdev->max_mod_size = PCICA_MAX_MOD_SIZE;
373 zdev->speed_rating = PCICA_SPEED_RATING;
374 zdev->max_exp_bit_length = PCICA_MAX_MOD_SIZE;
375 ap_dev->reply = &zdev->reply;
376 ap_dev->private = zdev;
377 rc = zcrypt_device_register(zdev);
378 if (rc)
379 goto out_free;
380 return 0;
381
382 out_free:
383 ap_dev->private = NULL;
384 zcrypt_device_free(zdev);
385 return rc;
386 }
387
388 /**
389 * This is called to remove the extended PCICA driver information
390 * if an AP device is removed.
391 */
zcrypt_pcica_remove(struct ap_device * ap_dev)392 static void zcrypt_pcica_remove(struct ap_device *ap_dev)
393 {
394 struct zcrypt_device *zdev = ap_dev->private;
395
396 zcrypt_device_unregister(zdev);
397 }
398
zcrypt_pcica_init(void)399 int __init zcrypt_pcica_init(void)
400 {
401 return ap_driver_register(&zcrypt_pcica_driver, THIS_MODULE, "pcica");
402 }
403
zcrypt_pcica_exit(void)404 void zcrypt_pcica_exit(void)
405 {
406 ap_driver_unregister(&zcrypt_pcica_driver);
407 }
408
409 module_init(zcrypt_pcica_init);
410 module_exit(zcrypt_pcica_exit);
411