1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  *  Copyright IBM Corp. 2001, 2012
4  *  Author(s): Robert Burroughs
5  *	       Eric Rossman (edrossma@us.ibm.com)
6  *
7  *  Hotplug & misc device support: Jochen Roehrig (roehrig@de.ibm.com)
8  *  Major cleanup & driver split: Martin Schwidefsky <schwidefsky@de.ibm.com>
9  *				  Ralph Wuerthner <rwuerthn@de.ibm.com>
10  *  MSGTYPE restruct:		  Holger Dengler <hd@linux.vnet.ibm.com>
11  */
12 
13 #define KMSG_COMPONENT "zcrypt"
14 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
15 
16 #include <linux/module.h>
17 #include <linux/slab.h>
18 #include <linux/init.h>
19 #include <linux/err.h>
20 #include <linux/atomic.h>
21 #include <linux/uaccess.h>
22 
23 #include "ap_bus.h"
24 #include "zcrypt_api.h"
25 #include "zcrypt_error.h"
26 #include "zcrypt_msgtype50.h"
27 
28 /* >= CEX3A: 4096 bits */
29 #define CEX3A_MAX_MOD_SIZE 512
30 
31 /* CEX2A: max outputdatalength + type80_hdr */
32 #define CEX2A_MAX_RESPONSE_SIZE 0x110
33 
34 /* >= CEX3A: 512 bit modulus, (max outputdatalength) + type80_hdr */
35 #define CEX3A_MAX_RESPONSE_SIZE 0x210
36 
37 MODULE_AUTHOR("IBM Corporation");
38 MODULE_DESCRIPTION("Cryptographic Accelerator (message type 50), " \
39 		   "Copyright IBM Corp. 2001, 2012");
40 MODULE_LICENSE("GPL");
41 
42 /**
43  * The type 50 message family is associated with a CEXxA cards.
44  *
45  * The four members of the family are described below.
46  *
47  * Note that all unsigned char arrays are right-justified and left-padded
48  * with zeroes.
49  *
50  * Note that all reserved fields must be zeroes.
51  */
52 struct type50_hdr {
53 	unsigned char	reserved1;
54 	unsigned char	msg_type_code;	/* 0x50 */
55 	unsigned short	msg_len;
56 	unsigned char	reserved2;
57 	unsigned char	ignored;
58 	unsigned short	reserved3;
59 } __packed;
60 
61 #define TYPE50_TYPE_CODE	0x50
62 
63 #define TYPE50_MEB1_FMT		0x0001
64 #define TYPE50_MEB2_FMT		0x0002
65 #define TYPE50_MEB3_FMT		0x0003
66 #define TYPE50_CRB1_FMT		0x0011
67 #define TYPE50_CRB2_FMT		0x0012
68 #define TYPE50_CRB3_FMT		0x0013
69 
70 /* Mod-Exp, with a small modulus */
71 struct type50_meb1_msg {
72 	struct type50_hdr header;
73 	unsigned short	keyblock_type;	/* 0x0001 */
74 	unsigned char	reserved[6];
75 	unsigned char	exponent[128];
76 	unsigned char	modulus[128];
77 	unsigned char	message[128];
78 } __packed;
79 
80 /* Mod-Exp, with a large modulus */
81 struct type50_meb2_msg {
82 	struct type50_hdr header;
83 	unsigned short	keyblock_type;	/* 0x0002 */
84 	unsigned char	reserved[6];
85 	unsigned char	exponent[256];
86 	unsigned char	modulus[256];
87 	unsigned char	message[256];
88 } __packed;
89 
90 /* Mod-Exp, with a larger modulus */
91 struct type50_meb3_msg {
92 	struct type50_hdr header;
93 	unsigned short	keyblock_type;	/* 0x0003 */
94 	unsigned char	reserved[6];
95 	unsigned char	exponent[512];
96 	unsigned char	modulus[512];
97 	unsigned char	message[512];
98 } __packed;
99 
100 /* CRT, with a small modulus */
101 struct type50_crb1_msg {
102 	struct type50_hdr header;
103 	unsigned short	keyblock_type;	/* 0x0011 */
104 	unsigned char	reserved[6];
105 	unsigned char	p[64];
106 	unsigned char	q[64];
107 	unsigned char	dp[64];
108 	unsigned char	dq[64];
109 	unsigned char	u[64];
110 	unsigned char	message[128];
111 } __packed;
112 
113 /* CRT, with a large modulus */
114 struct type50_crb2_msg {
115 	struct type50_hdr header;
116 	unsigned short	keyblock_type;	/* 0x0012 */
117 	unsigned char	reserved[6];
118 	unsigned char	p[128];
119 	unsigned char	q[128];
120 	unsigned char	dp[128];
121 	unsigned char	dq[128];
122 	unsigned char	u[128];
123 	unsigned char	message[256];
124 } __packed;
125 
126 /* CRT, with a larger modulus */
127 struct type50_crb3_msg {
128 	struct type50_hdr header;
129 	unsigned short	keyblock_type;	/* 0x0013 */
130 	unsigned char	reserved[6];
131 	unsigned char	p[256];
132 	unsigned char	q[256];
133 	unsigned char	dp[256];
134 	unsigned char	dq[256];
135 	unsigned char	u[256];
136 	unsigned char	message[512];
137 } __packed;
138 
139 /**
140  * The type 80 response family is associated with a CEXxA cards.
141  *
142  * Note that all unsigned char arrays are right-justified and left-padded
143  * with zeroes.
144  *
145  * Note that all reserved fields must be zeroes.
146  */
147 
148 #define TYPE80_RSP_CODE 0x80
149 
150 struct type80_hdr {
151 	unsigned char	reserved1;
152 	unsigned char	type;		/* 0x80 */
153 	unsigned short	len;
154 	unsigned char	code;		/* 0x00 */
155 	unsigned char	reserved2[3];
156 	unsigned char	reserved3[8];
157 } __packed;
158 
159 unsigned int get_rsa_modex_fc(struct ica_rsa_modexpo *mex, int *fcode)
160 {
161 
162 	if (!mex->inputdatalength)
163 		return -EINVAL;
164 
165 	if (mex->inputdatalength <= 128)	/* 1024 bit */
166 		*fcode = MEX_1K;
167 	else if (mex->inputdatalength <= 256)	/* 2048 bit */
168 		*fcode = MEX_2K;
169 	else					/* 4096 bit */
170 		*fcode = MEX_4K;
171 
172 	return 0;
173 }
174 
175 unsigned int get_rsa_crt_fc(struct ica_rsa_modexpo_crt *crt, int *fcode)
176 {
177 
178 	if (!crt->inputdatalength)
179 		return -EINVAL;
180 
181 	if (crt->inputdatalength <= 128)	/* 1024 bit */
182 		*fcode = CRT_1K;
183 	else if (crt->inputdatalength <= 256)	/* 2048 bit */
184 		*fcode = CRT_2K;
185 	else					/* 4096 bit */
186 		*fcode = CRT_4K;
187 
188 	return 0;
189 }
190 
191 /**
192  * Convert a ICAMEX message to a type50 MEX message.
193  *
194  * @zq: crypto queue pointer
195  * @ap_msg: crypto request pointer
196  * @mex: pointer to user input data
197  *
198  * Returns 0 on success or -EFAULT.
199  */
200 static int ICAMEX_msg_to_type50MEX_msg(struct zcrypt_queue *zq,
201 				       struct ap_message *ap_msg,
202 				       struct ica_rsa_modexpo *mex)
203 {
204 	unsigned char *mod, *exp, *inp;
205 	int mod_len;
206 
207 	mod_len = mex->inputdatalength;
208 
209 	if (mod_len <= 128) {
210 		struct type50_meb1_msg *meb1 = ap_msg->message;
211 
212 		memset(meb1, 0, sizeof(*meb1));
213 		ap_msg->length = sizeof(*meb1);
214 		meb1->header.msg_type_code = TYPE50_TYPE_CODE;
215 		meb1->header.msg_len = sizeof(*meb1);
216 		meb1->keyblock_type = TYPE50_MEB1_FMT;
217 		mod = meb1->modulus + sizeof(meb1->modulus) - mod_len;
218 		exp = meb1->exponent + sizeof(meb1->exponent) - mod_len;
219 		inp = meb1->message + sizeof(meb1->message) - mod_len;
220 	} else if (mod_len <= 256) {
221 		struct type50_meb2_msg *meb2 = ap_msg->message;
222 
223 		memset(meb2, 0, sizeof(*meb2));
224 		ap_msg->length = sizeof(*meb2);
225 		meb2->header.msg_type_code = TYPE50_TYPE_CODE;
226 		meb2->header.msg_len = sizeof(*meb2);
227 		meb2->keyblock_type = TYPE50_MEB2_FMT;
228 		mod = meb2->modulus + sizeof(meb2->modulus) - mod_len;
229 		exp = meb2->exponent + sizeof(meb2->exponent) - mod_len;
230 		inp = meb2->message + sizeof(meb2->message) - mod_len;
231 	} else if (mod_len <= 512) {
232 		struct type50_meb3_msg *meb3 = ap_msg->message;
233 
234 		memset(meb3, 0, sizeof(*meb3));
235 		ap_msg->length = sizeof(*meb3);
236 		meb3->header.msg_type_code = TYPE50_TYPE_CODE;
237 		meb3->header.msg_len = sizeof(*meb3);
238 		meb3->keyblock_type = TYPE50_MEB3_FMT;
239 		mod = meb3->modulus + sizeof(meb3->modulus) - mod_len;
240 		exp = meb3->exponent + sizeof(meb3->exponent) - mod_len;
241 		inp = meb3->message + sizeof(meb3->message) - mod_len;
242 	} else
243 		return -EINVAL;
244 
245 	if (copy_from_user(mod, mex->n_modulus, mod_len) ||
246 	    copy_from_user(exp, mex->b_key, mod_len) ||
247 	    copy_from_user(inp, mex->inputdata, mod_len))
248 		return -EFAULT;
249 	return 0;
250 }
251 
252 /**
253  * Convert a ICACRT message to a type50 CRT message.
254  *
255  * @zq: crypto queue pointer
256  * @ap_msg: crypto request pointer
257  * @crt: pointer to user input data
258  *
259  * Returns 0 on success or -EFAULT.
260  */
261 static int ICACRT_msg_to_type50CRT_msg(struct zcrypt_queue *zq,
262 				       struct ap_message *ap_msg,
263 				       struct ica_rsa_modexpo_crt *crt)
264 {
265 	int mod_len, short_len;
266 	unsigned char *p, *q, *dp, *dq, *u, *inp;
267 
268 	mod_len = crt->inputdatalength;
269 	short_len = (mod_len + 1) / 2;
270 
271 	/*
272 	 * CEX2A and CEX3A w/o FW update can handle requests up to
273 	 * 256 byte modulus (2k keys).
274 	 * CEX3A with FW update and newer CEXxA cards are able to handle
275 	 * 512 byte modulus (4k keys).
276 	 */
277 	if (mod_len <= 128) {		/* up to 1024 bit key size */
278 		struct type50_crb1_msg *crb1 = ap_msg->message;
279 
280 		memset(crb1, 0, sizeof(*crb1));
281 		ap_msg->length = sizeof(*crb1);
282 		crb1->header.msg_type_code = TYPE50_TYPE_CODE;
283 		crb1->header.msg_len = sizeof(*crb1);
284 		crb1->keyblock_type = TYPE50_CRB1_FMT;
285 		p = crb1->p + sizeof(crb1->p) - short_len;
286 		q = crb1->q + sizeof(crb1->q) - short_len;
287 		dp = crb1->dp + sizeof(crb1->dp) - short_len;
288 		dq = crb1->dq + sizeof(crb1->dq) - short_len;
289 		u = crb1->u + sizeof(crb1->u) - short_len;
290 		inp = crb1->message + sizeof(crb1->message) - mod_len;
291 	} else if (mod_len <= 256) {	/* up to 2048 bit key size */
292 		struct type50_crb2_msg *crb2 = ap_msg->message;
293 
294 		memset(crb2, 0, sizeof(*crb2));
295 		ap_msg->length = sizeof(*crb2);
296 		crb2->header.msg_type_code = TYPE50_TYPE_CODE;
297 		crb2->header.msg_len = sizeof(*crb2);
298 		crb2->keyblock_type = TYPE50_CRB2_FMT;
299 		p = crb2->p + sizeof(crb2->p) - short_len;
300 		q = crb2->q + sizeof(crb2->q) - short_len;
301 		dp = crb2->dp + sizeof(crb2->dp) - short_len;
302 		dq = crb2->dq + sizeof(crb2->dq) - short_len;
303 		u = crb2->u + sizeof(crb2->u) - short_len;
304 		inp = crb2->message + sizeof(crb2->message) - mod_len;
305 	} else if ((mod_len <= 512) &&	/* up to 4096 bit key size */
306 		   (zq->zcard->max_mod_size == CEX3A_MAX_MOD_SIZE)) {
307 		struct type50_crb3_msg *crb3 = ap_msg->message;
308 
309 		memset(crb3, 0, sizeof(*crb3));
310 		ap_msg->length = sizeof(*crb3);
311 		crb3->header.msg_type_code = TYPE50_TYPE_CODE;
312 		crb3->header.msg_len = sizeof(*crb3);
313 		crb3->keyblock_type = TYPE50_CRB3_FMT;
314 		p = crb3->p + sizeof(crb3->p) - short_len;
315 		q = crb3->q + sizeof(crb3->q) - short_len;
316 		dp = crb3->dp + sizeof(crb3->dp) - short_len;
317 		dq = crb3->dq + sizeof(crb3->dq) - short_len;
318 		u = crb3->u + sizeof(crb3->u) - short_len;
319 		inp = crb3->message + sizeof(crb3->message) - mod_len;
320 	} else
321 		return -EINVAL;
322 
323 	/*
324 	 * correct the offset of p, bp and mult_inv according zcrypt.h
325 	 * block size right aligned (skip the first byte)
326 	 */
327 	if (copy_from_user(p, crt->np_prime + MSGTYPE_ADJUSTMENT, short_len) ||
328 	    copy_from_user(q, crt->nq_prime, short_len) ||
329 	    copy_from_user(dp, crt->bp_key + MSGTYPE_ADJUSTMENT, short_len) ||
330 	    copy_from_user(dq, crt->bq_key, short_len) ||
331 	    copy_from_user(u, crt->u_mult_inv + MSGTYPE_ADJUSTMENT, short_len) ||
332 	    copy_from_user(inp, crt->inputdata, mod_len))
333 		return -EFAULT;
334 
335 	return 0;
336 }
337 
338 /**
339  * Copy results from a type 80 reply message back to user space.
340  *
341  * @zq: crypto device pointer
342  * @reply: reply AP message.
343  * @data: pointer to user output data
344  * @length: size of user output data
345  *
346  * Returns 0 on success or -EFAULT.
347  */
348 static int convert_type80(struct zcrypt_queue *zq,
349 			  struct ap_message *reply,
350 			  char __user *outputdata,
351 			  unsigned int outputdatalength)
352 {
353 	struct type80_hdr *t80h = reply->message;
354 	unsigned char *data;
355 
356 	if (t80h->len < sizeof(*t80h) + outputdatalength) {
357 		/* The result is too short, the CEXxA card may not do that.. */
358 		zq->online = 0;
359 		pr_err("Cryptographic device %02x.%04x failed and was set offline\n",
360 		       AP_QID_CARD(zq->queue->qid),
361 		       AP_QID_QUEUE(zq->queue->qid));
362 		ZCRYPT_DBF(DBF_ERR,
363 			   "device=%02x.%04x code=0x%02x => online=0 rc=EAGAIN\n",
364 			   AP_QID_CARD(zq->queue->qid),
365 			   AP_QID_QUEUE(zq->queue->qid),
366 			   t80h->code);
367 		return -EAGAIN;	/* repeat the request on a different device. */
368 	}
369 	if (zq->zcard->user_space_type == ZCRYPT_CEX2A)
370 		BUG_ON(t80h->len > CEX2A_MAX_RESPONSE_SIZE);
371 	else
372 		BUG_ON(t80h->len > CEX3A_MAX_RESPONSE_SIZE);
373 	data = reply->message + t80h->len - outputdatalength;
374 	if (copy_to_user(outputdata, data, outputdatalength))
375 		return -EFAULT;
376 	return 0;
377 }
378 
379 static int convert_response(struct zcrypt_queue *zq,
380 			    struct ap_message *reply,
381 			    char __user *outputdata,
382 			    unsigned int outputdatalength)
383 {
384 	/* Response type byte is the second byte in the response. */
385 	unsigned char rtype = ((unsigned char *) reply->message)[1];
386 
387 	switch (rtype) {
388 	case TYPE82_RSP_CODE:
389 	case TYPE88_RSP_CODE:
390 		return convert_error(zq, reply);
391 	case TYPE80_RSP_CODE:
392 		return convert_type80(zq, reply,
393 				      outputdata, outputdatalength);
394 	default: /* Unknown response type, this should NEVER EVER happen */
395 		zq->online = 0;
396 		pr_err("Cryptographic device %02x.%04x failed and was set offline\n",
397 		       AP_QID_CARD(zq->queue->qid),
398 		       AP_QID_QUEUE(zq->queue->qid));
399 		ZCRYPT_DBF(DBF_ERR,
400 			   "device=%02x.%04x rtype=0x%02x => online=0 rc=EAGAIN\n",
401 			   AP_QID_CARD(zq->queue->qid),
402 			   AP_QID_QUEUE(zq->queue->qid),
403 			   (unsigned int) rtype);
404 		return -EAGAIN;	/* repeat the request on a different device. */
405 	}
406 }
407 
408 /**
409  * This function is called from the AP bus code after a crypto request
410  * "msg" has finished with the reply message "reply".
411  * It is called from tasklet context.
412  * @aq: pointer to the AP device
413  * @msg: pointer to the AP message
414  * @reply: pointer to the AP reply message
415  */
416 static void zcrypt_cex2a_receive(struct ap_queue *aq,
417 				 struct ap_message *msg,
418 				 struct ap_message *reply)
419 {
420 	static struct error_hdr error_reply = {
421 		.type = TYPE82_RSP_CODE,
422 		.reply_code = REP82_ERROR_MACHINE_FAILURE,
423 	};
424 	struct type80_hdr *t80h;
425 	int length;
426 
427 	/* Copy the reply message to the request message buffer. */
428 	if (!reply)
429 		goto out;	/* ap_msg->rc indicates the error */
430 	t80h = reply->message;
431 	if (t80h->type == TYPE80_RSP_CODE) {
432 		if (aq->ap_dev.device_type == AP_DEVICE_TYPE_CEX2A)
433 			length = min_t(int,
434 				       CEX2A_MAX_RESPONSE_SIZE, t80h->len);
435 		else
436 			length = min_t(int,
437 				       CEX3A_MAX_RESPONSE_SIZE, t80h->len);
438 		memcpy(msg->message, reply->message, length);
439 	} else
440 		memcpy(msg->message, reply->message, sizeof(error_reply));
441 out:
442 	complete((struct completion *) msg->private);
443 }
444 
445 static atomic_t zcrypt_step = ATOMIC_INIT(0);
446 
447 /**
448  * The request distributor calls this function if it picked the CEXxA
449  * device to handle a modexpo request.
450  * @zq: pointer to zcrypt_queue structure that identifies the
451  *	CEXxA device to the request distributor
452  * @mex: pointer to the modexpo request buffer
453  */
454 static long zcrypt_cex2a_modexpo(struct zcrypt_queue *zq,
455 				 struct ica_rsa_modexpo *mex)
456 {
457 	struct ap_message ap_msg;
458 	struct completion work;
459 	int rc;
460 
461 	ap_init_message(&ap_msg);
462 	if (zq->zcard->user_space_type == ZCRYPT_CEX2A)
463 		ap_msg.message = kmalloc(MSGTYPE50_CRB2_MAX_MSG_SIZE,
464 					 GFP_KERNEL);
465 	else
466 		ap_msg.message = kmalloc(MSGTYPE50_CRB3_MAX_MSG_SIZE,
467 					 GFP_KERNEL);
468 	if (!ap_msg.message)
469 		return -ENOMEM;
470 	ap_msg.receive = zcrypt_cex2a_receive;
471 	ap_msg.psmid = (((unsigned long long) current->pid) << 32) +
472 				atomic_inc_return(&zcrypt_step);
473 	ap_msg.private = &work;
474 	rc = ICAMEX_msg_to_type50MEX_msg(zq, &ap_msg, mex);
475 	if (rc)
476 		goto out_free;
477 	init_completion(&work);
478 	ap_queue_message(zq->queue, &ap_msg);
479 	rc = wait_for_completion_interruptible(&work);
480 	if (rc == 0) {
481 		rc = ap_msg.rc;
482 		if (rc == 0)
483 			rc = convert_response(zq, &ap_msg, mex->outputdata,
484 					      mex->outputdatalength);
485 	} else
486 		/* Signal pending. */
487 		ap_cancel_message(zq->queue, &ap_msg);
488 out_free:
489 	kfree(ap_msg.message);
490 	return rc;
491 }
492 
493 /**
494  * The request distributor calls this function if it picked the CEXxA
495  * device to handle a modexpo_crt request.
496  * @zq: pointer to zcrypt_queue structure that identifies the
497  *	CEXxA device to the request distributor
498  * @crt: pointer to the modexpoc_crt request buffer
499  */
500 static long zcrypt_cex2a_modexpo_crt(struct zcrypt_queue *zq,
501 				     struct ica_rsa_modexpo_crt *crt)
502 {
503 	struct ap_message ap_msg;
504 	struct completion work;
505 	int rc;
506 
507 	ap_init_message(&ap_msg);
508 	if (zq->zcard->user_space_type == ZCRYPT_CEX2A)
509 		ap_msg.message = kmalloc(MSGTYPE50_CRB2_MAX_MSG_SIZE,
510 					 GFP_KERNEL);
511 	else
512 		ap_msg.message = kmalloc(MSGTYPE50_CRB3_MAX_MSG_SIZE,
513 					 GFP_KERNEL);
514 	if (!ap_msg.message)
515 		return -ENOMEM;
516 	ap_msg.receive = zcrypt_cex2a_receive;
517 	ap_msg.psmid = (((unsigned long long) current->pid) << 32) +
518 				atomic_inc_return(&zcrypt_step);
519 	ap_msg.private = &work;
520 	rc = ICACRT_msg_to_type50CRT_msg(zq, &ap_msg, crt);
521 	if (rc)
522 		goto out_free;
523 	init_completion(&work);
524 	ap_queue_message(zq->queue, &ap_msg);
525 	rc = wait_for_completion_interruptible(&work);
526 	if (rc == 0) {
527 		rc = ap_msg.rc;
528 		if (rc == 0)
529 			rc = convert_response(zq, &ap_msg, crt->outputdata,
530 					      crt->outputdatalength);
531 	} else
532 		/* Signal pending. */
533 		ap_cancel_message(zq->queue, &ap_msg);
534 out_free:
535 	kfree(ap_msg.message);
536 	return rc;
537 }
538 
539 /**
540  * The crypto operations for message type 50.
541  */
542 static struct zcrypt_ops zcrypt_msgtype50_ops = {
543 	.rsa_modexpo = zcrypt_cex2a_modexpo,
544 	.rsa_modexpo_crt = zcrypt_cex2a_modexpo_crt,
545 	.owner = THIS_MODULE,
546 	.name = MSGTYPE50_NAME,
547 	.variant = MSGTYPE50_VARIANT_DEFAULT,
548 };
549 
550 void __init zcrypt_msgtype50_init(void)
551 {
552 	zcrypt_msgtype_register(&zcrypt_msgtype50_ops);
553 }
554 
555 void __exit zcrypt_msgtype50_exit(void)
556 {
557 	zcrypt_msgtype_unregister(&zcrypt_msgtype50_ops);
558 }
559