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_pcica.h"
38
39 #define PCICA_MIN_MOD_SIZE 1 /* 8 bits */
40 #define PCICA_MAX_MOD_SIZE 256 /* 2048 bits */
41
42 #define PCICA_SPEED_RATING 2800
43
44 #define PCICA_MAX_MESSAGE_SIZE 0x3a0 /* sizeof(struct type4_lcr) */
45 #define PCICA_MAX_RESPONSE_SIZE 0x110 /* max outputdatalength + type80_hdr */
46
47 #define PCICA_CLEANUP_TIME (15*HZ)
48
49 static struct ap_device_id zcrypt_pcica_ids[] = {
50 { AP_DEVICE(AP_DEVICE_TYPE_PCICA) },
51 { /* end of list */ },
52 };
53
54 MODULE_DEVICE_TABLE(ap, zcrypt_pcica_ids);
55 MODULE_AUTHOR("IBM Corporation");
56 MODULE_DESCRIPTION("PCICA Cryptographic Coprocessor device driver, "
57 "Copyright IBM Corp. 2001, 2006");
58 MODULE_LICENSE("GPL");
59
60 static int zcrypt_pcica_probe(struct ap_device *ap_dev);
61 static void zcrypt_pcica_remove(struct ap_device *ap_dev);
62 static void zcrypt_pcica_receive(struct ap_device *, struct ap_message *,
63 struct ap_message *);
64
65 static struct ap_driver zcrypt_pcica_driver = {
66 .probe = zcrypt_pcica_probe,
67 .remove = zcrypt_pcica_remove,
68 .ids = zcrypt_pcica_ids,
69 .request_timeout = PCICA_CLEANUP_TIME,
70 };
71
72 /**
73 * Convert a ICAMEX message to a type4 MEX message.
74 *
75 * @zdev: crypto device pointer
76 * @zreq: crypto request pointer
77 * @mex: pointer to user input data
78 *
79 * Returns 0 on success or -EFAULT.
80 */
ICAMEX_msg_to_type4MEX_msg(struct zcrypt_device * zdev,struct ap_message * ap_msg,struct ica_rsa_modexpo * mex)81 static int ICAMEX_msg_to_type4MEX_msg(struct zcrypt_device *zdev,
82 struct ap_message *ap_msg,
83 struct ica_rsa_modexpo *mex)
84 {
85 unsigned char *modulus, *exponent, *message;
86 int mod_len;
87
88 mod_len = mex->inputdatalength;
89
90 if (mod_len <= 128) {
91 struct type4_sme *sme = ap_msg->message;
92 memset(sme, 0, sizeof(*sme));
93 ap_msg->length = sizeof(*sme);
94 sme->header.msg_fmt = TYPE4_SME_FMT;
95 sme->header.msg_len = sizeof(*sme);
96 sme->header.msg_type_code = TYPE4_TYPE_CODE;
97 sme->header.request_code = TYPE4_REQU_CODE;
98 modulus = sme->modulus + sizeof(sme->modulus) - mod_len;
99 exponent = sme->exponent + sizeof(sme->exponent) - mod_len;
100 message = sme->message + sizeof(sme->message) - mod_len;
101 } else {
102 struct type4_lme *lme = ap_msg->message;
103 memset(lme, 0, sizeof(*lme));
104 ap_msg->length = sizeof(*lme);
105 lme->header.msg_fmt = TYPE4_LME_FMT;
106 lme->header.msg_len = sizeof(*lme);
107 lme->header.msg_type_code = TYPE4_TYPE_CODE;
108 lme->header.request_code = TYPE4_REQU_CODE;
109 modulus = lme->modulus + sizeof(lme->modulus) - mod_len;
110 exponent = lme->exponent + sizeof(lme->exponent) - mod_len;
111 message = lme->message + sizeof(lme->message) - mod_len;
112 }
113
114 if (copy_from_user(modulus, mex->n_modulus, mod_len) ||
115 copy_from_user(exponent, mex->b_key, mod_len) ||
116 copy_from_user(message, mex->inputdata, mod_len))
117 return -EFAULT;
118 return 0;
119 }
120
121 /**
122 * Convert a ICACRT message to a type4 CRT message.
123 *
124 * @zdev: crypto device pointer
125 * @zreq: crypto request pointer
126 * @crt: pointer to user input data
127 *
128 * Returns 0 on success or -EFAULT.
129 */
ICACRT_msg_to_type4CRT_msg(struct zcrypt_device * zdev,struct ap_message * ap_msg,struct ica_rsa_modexpo_crt * crt)130 static int ICACRT_msg_to_type4CRT_msg(struct zcrypt_device *zdev,
131 struct ap_message *ap_msg,
132 struct ica_rsa_modexpo_crt *crt)
133 {
134 unsigned char *p, *q, *dp, *dq, *u, *inp;
135 int mod_len, short_len, long_len;
136
137 mod_len = crt->inputdatalength;
138 short_len = mod_len / 2;
139 long_len = mod_len / 2 + 8;
140
141 if (mod_len <= 128) {
142 struct type4_scr *scr = ap_msg->message;
143 memset(scr, 0, sizeof(*scr));
144 ap_msg->length = sizeof(*scr);
145 scr->header.msg_type_code = TYPE4_TYPE_CODE;
146 scr->header.request_code = TYPE4_REQU_CODE;
147 scr->header.msg_fmt = TYPE4_SCR_FMT;
148 scr->header.msg_len = sizeof(*scr);
149 p = scr->p + sizeof(scr->p) - long_len;
150 q = scr->q + sizeof(scr->q) - short_len;
151 dp = scr->dp + sizeof(scr->dp) - long_len;
152 dq = scr->dq + sizeof(scr->dq) - short_len;
153 u = scr->u + sizeof(scr->u) - long_len;
154 inp = scr->message + sizeof(scr->message) - mod_len;
155 } else {
156 struct type4_lcr *lcr = ap_msg->message;
157 memset(lcr, 0, sizeof(*lcr));
158 ap_msg->length = sizeof(*lcr);
159 lcr->header.msg_type_code = TYPE4_TYPE_CODE;
160 lcr->header.request_code = TYPE4_REQU_CODE;
161 lcr->header.msg_fmt = TYPE4_LCR_FMT;
162 lcr->header.msg_len = sizeof(*lcr);
163 p = lcr->p + sizeof(lcr->p) - long_len;
164 q = lcr->q + sizeof(lcr->q) - short_len;
165 dp = lcr->dp + sizeof(lcr->dp) - long_len;
166 dq = lcr->dq + sizeof(lcr->dq) - short_len;
167 u = lcr->u + sizeof(lcr->u) - long_len;
168 inp = lcr->message + sizeof(lcr->message) - mod_len;
169 }
170
171 if (copy_from_user(p, crt->np_prime, long_len) ||
172 copy_from_user(q, crt->nq_prime, short_len) ||
173 copy_from_user(dp, crt->bp_key, long_len) ||
174 copy_from_user(dq, crt->bq_key, short_len) ||
175 copy_from_user(u, crt->u_mult_inv, long_len) ||
176 copy_from_user(inp, crt->inputdata, mod_len))
177 return -EFAULT;
178 return 0;
179 }
180
181 /**
182 * Copy results from a type 84 reply message back to user space.
183 *
184 * @zdev: crypto device pointer
185 * @reply: reply AP message.
186 * @data: pointer to user output data
187 * @length: size of user output data
188 *
189 * Returns 0 on success or -EFAULT.
190 */
convert_type84(struct zcrypt_device * zdev,struct ap_message * reply,char __user * outputdata,unsigned int outputdatalength)191 static int convert_type84(struct zcrypt_device *zdev,
192 struct ap_message *reply,
193 char __user *outputdata,
194 unsigned int outputdatalength)
195 {
196 struct type84_hdr *t84h = reply->message;
197 char *data;
198
199 if (t84h->len < sizeof(*t84h) + outputdatalength) {
200 /* The result is too short, the PCICA card may not do that.. */
201 zdev->online = 0;
202 return -EAGAIN; /* repeat the request on a different device. */
203 }
204 BUG_ON(t84h->len > PCICA_MAX_RESPONSE_SIZE);
205 data = reply->message + t84h->len - outputdatalength;
206 if (copy_to_user(outputdata, data, outputdatalength))
207 return -EFAULT;
208 return 0;
209 }
210
convert_response(struct zcrypt_device * zdev,struct ap_message * reply,char __user * outputdata,unsigned int outputdatalength)211 static int convert_response(struct zcrypt_device *zdev,
212 struct ap_message *reply,
213 char __user *outputdata,
214 unsigned int outputdatalength)
215 {
216 /* Response type byte is the second byte in the response. */
217 switch (((unsigned char *) reply->message)[1]) {
218 case TYPE82_RSP_CODE:
219 case TYPE88_RSP_CODE:
220 return convert_error(zdev, reply);
221 case TYPE84_RSP_CODE:
222 return convert_type84(zdev, reply,
223 outputdata, outputdatalength);
224 default: /* Unknown response type, this should NEVER EVER happen */
225 zdev->online = 0;
226 return -EAGAIN; /* repeat the request on a different device. */
227 }
228 }
229
230 /**
231 * This function is called from the AP bus code after a crypto request
232 * "msg" has finished with the reply message "reply".
233 * It is called from tasklet context.
234 * @ap_dev: pointer to the AP device
235 * @msg: pointer to the AP message
236 * @reply: pointer to the AP reply message
237 */
zcrypt_pcica_receive(struct ap_device * ap_dev,struct ap_message * msg,struct ap_message * reply)238 static void zcrypt_pcica_receive(struct ap_device *ap_dev,
239 struct ap_message *msg,
240 struct ap_message *reply)
241 {
242 static struct error_hdr error_reply = {
243 .type = TYPE82_RSP_CODE,
244 .reply_code = REP82_ERROR_MACHINE_FAILURE,
245 };
246 struct type84_hdr *t84h;
247 int length;
248
249 /* Copy the reply message to the request message buffer. */
250 if (IS_ERR(reply)) {
251 memcpy(msg->message, &error_reply, sizeof(error_reply));
252 goto out;
253 }
254 t84h = reply->message;
255 if (t84h->code == TYPE84_RSP_CODE) {
256 length = min(PCICA_MAX_RESPONSE_SIZE, (int) t84h->len);
257 memcpy(msg->message, reply->message, length);
258 } else
259 memcpy(msg->message, reply->message, sizeof error_reply);
260 out:
261 complete((struct completion *) msg->private);
262 }
263
264 static atomic_t zcrypt_step = ATOMIC_INIT(0);
265
266 /**
267 * The request distributor calls this function if it picked the PCICA
268 * device to handle a modexpo request.
269 * @zdev: pointer to zcrypt_device structure that identifies the
270 * PCICA device to the request distributor
271 * @mex: pointer to the modexpo request buffer
272 */
zcrypt_pcica_modexpo(struct zcrypt_device * zdev,struct ica_rsa_modexpo * mex)273 static long zcrypt_pcica_modexpo(struct zcrypt_device *zdev,
274 struct ica_rsa_modexpo *mex)
275 {
276 struct ap_message ap_msg;
277 struct completion work;
278 int rc;
279
280 ap_init_message(&ap_msg);
281 ap_msg.message = kmalloc(PCICA_MAX_MESSAGE_SIZE, GFP_KERNEL);
282 if (!ap_msg.message)
283 return -ENOMEM;
284 ap_msg.receive = zcrypt_pcica_receive;
285 ap_msg.psmid = (((unsigned long long) current->pid) << 32) +
286 atomic_inc_return(&zcrypt_step);
287 ap_msg.private = &work;
288 rc = ICAMEX_msg_to_type4MEX_msg(zdev, &ap_msg, mex);
289 if (rc)
290 goto out_free;
291 init_completion(&work);
292 ap_queue_message(zdev->ap_dev, &ap_msg);
293 rc = wait_for_completion_interruptible(&work);
294 if (rc == 0)
295 rc = convert_response(zdev, &ap_msg, mex->outputdata,
296 mex->outputdatalength);
297 else
298 /* Signal pending. */
299 ap_cancel_message(zdev->ap_dev, &ap_msg);
300 out_free:
301 kfree(ap_msg.message);
302 return rc;
303 }
304
305 /**
306 * The request distributor calls this function if it picked the PCICA
307 * device to handle a modexpo_crt request.
308 * @zdev: pointer to zcrypt_device structure that identifies the
309 * PCICA device to the request distributor
310 * @crt: pointer to the modexpoc_crt request buffer
311 */
zcrypt_pcica_modexpo_crt(struct zcrypt_device * zdev,struct ica_rsa_modexpo_crt * crt)312 static long zcrypt_pcica_modexpo_crt(struct zcrypt_device *zdev,
313 struct ica_rsa_modexpo_crt *crt)
314 {
315 struct ap_message ap_msg;
316 struct completion work;
317 int rc;
318
319 ap_init_message(&ap_msg);
320 ap_msg.message = kmalloc(PCICA_MAX_MESSAGE_SIZE, GFP_KERNEL);
321 if (!ap_msg.message)
322 return -ENOMEM;
323 ap_msg.receive = zcrypt_pcica_receive;
324 ap_msg.psmid = (((unsigned long long) current->pid) << 32) +
325 atomic_inc_return(&zcrypt_step);
326 ap_msg.private = &work;
327 rc = ICACRT_msg_to_type4CRT_msg(zdev, &ap_msg, crt);
328 if (rc)
329 goto out_free;
330 init_completion(&work);
331 ap_queue_message(zdev->ap_dev, &ap_msg);
332 rc = wait_for_completion_interruptible(&work);
333 if (rc == 0)
334 rc = convert_response(zdev, &ap_msg, crt->outputdata,
335 crt->outputdatalength);
336 else
337 /* Signal pending. */
338 ap_cancel_message(zdev->ap_dev, &ap_msg);
339 out_free:
340 kfree(ap_msg.message);
341 return rc;
342 }
343
344 /**
345 * The crypto operations for a PCICA card.
346 */
347 static struct zcrypt_ops zcrypt_pcica_ops = {
348 .rsa_modexpo = zcrypt_pcica_modexpo,
349 .rsa_modexpo_crt = zcrypt_pcica_modexpo_crt,
350 };
351
352 /**
353 * Probe function for PCICA cards. It always accepts the AP device
354 * since the bus_match already checked the hardware type.
355 * @ap_dev: pointer to the AP device.
356 */
zcrypt_pcica_probe(struct ap_device * ap_dev)357 static int zcrypt_pcica_probe(struct ap_device *ap_dev)
358 {
359 struct zcrypt_device *zdev;
360 int rc;
361
362 zdev = zcrypt_device_alloc(PCICA_MAX_RESPONSE_SIZE);
363 if (!zdev)
364 return -ENOMEM;
365 zdev->ap_dev = ap_dev;
366 zdev->ops = &zcrypt_pcica_ops;
367 zdev->online = 1;
368 zdev->user_space_type = ZCRYPT_PCICA;
369 zdev->type_string = "PCICA";
370 zdev->min_mod_size = PCICA_MIN_MOD_SIZE;
371 zdev->max_mod_size = PCICA_MAX_MOD_SIZE;
372 zdev->speed_rating = PCICA_SPEED_RATING;
373 zdev->max_exp_bit_length = PCICA_MAX_MOD_SIZE;
374 ap_dev->reply = &zdev->reply;
375 ap_dev->private = zdev;
376 rc = zcrypt_device_register(zdev);
377 if (rc)
378 goto out_free;
379 return 0;
380
381 out_free:
382 ap_dev->private = NULL;
383 zcrypt_device_free(zdev);
384 return rc;
385 }
386
387 /**
388 * This is called to remove the extended PCICA driver information
389 * if an AP device is removed.
390 */
zcrypt_pcica_remove(struct ap_device * ap_dev)391 static void zcrypt_pcica_remove(struct ap_device *ap_dev)
392 {
393 struct zcrypt_device *zdev = ap_dev->private;
394
395 zcrypt_device_unregister(zdev);
396 }
397
zcrypt_pcica_init(void)398 int __init zcrypt_pcica_init(void)
399 {
400 return ap_driver_register(&zcrypt_pcica_driver, THIS_MODULE, "pcica");
401 }
402
zcrypt_pcica_exit(void)403 void zcrypt_pcica_exit(void)
404 {
405 ap_driver_unregister(&zcrypt_pcica_driver);
406 }
407
408 module_init(zcrypt_pcica_init);
409 module_exit(zcrypt_pcica_exit);
410