zcrypt_msgtype50.c

  1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 *  Copyright IBM Corp. 2001, 2023
  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 pr_fmt(fmt) "zcrypt: " fmt
 14
 15#include <linux/module.h>
 16#include <linux/slab.h>
 17#include <linux/init.h>
 18#include <linux/err.h>
 19#include <linux/atomic.h>
 20#include <linux/uaccess.h>
 21
 22#include "ap_bus.h"
 23#include "zcrypt_api.h"
 24#include "zcrypt_error.h"
 25#include "zcrypt_msgtype50.h"
 26
 27/* >= CEX3A: 4096 bits */
 28#define CEX3A_MAX_MOD_SIZE 512
 29
 30/* >= CEX3A: 512 bit modulus, (max outputdatalength) + type80_hdr */
 31#define CEX3A_MAX_RESPONSE_SIZE 0x210
 32
 33MODULE_AUTHOR("IBM Corporation");
 34MODULE_DESCRIPTION("Cryptographic Accelerator (message type 50), " \
 35		   "Copyright IBM Corp. 2001, 2023");
 36MODULE_LICENSE("GPL");
 37
 38/*
 39 * The type 50 message family is associated with a CEXxA cards.
 40 *
 41 * The four members of the family are described below.
 42 *
 43 * Note that all unsigned char arrays are right-justified and left-padded
 44 * with zeroes.
 45 *
 46 * Note that all reserved fields must be zeroes.
 47 */
 48struct type50_hdr {
 49	unsigned char	reserved1;
 50	unsigned char	msg_type_code;	/* 0x50 */
 51	unsigned short	msg_len;
 52	unsigned char	reserved2;
 53	unsigned char	ignored;
 54	unsigned short	reserved3;
 55} __packed;
 56
 57#define TYPE50_TYPE_CODE	0x50
 58
 59#define TYPE50_MEB1_FMT		0x0001
 60#define TYPE50_MEB2_FMT		0x0002
 61#define TYPE50_MEB3_FMT		0x0003
 62#define TYPE50_CRB1_FMT		0x0011
 63#define TYPE50_CRB2_FMT		0x0012
 64#define TYPE50_CRB3_FMT		0x0013
 65
 66/* Mod-Exp, with a small modulus */
 67struct type50_meb1_msg {
 68	struct type50_hdr header;
 69	unsigned short	keyblock_type;	/* 0x0001 */
 70	unsigned char	reserved[6];
 71	unsigned char	exponent[128];
 72	unsigned char	modulus[128];
 73	unsigned char	message[128];
 74} __packed;
 75
 76/* Mod-Exp, with a large modulus */
 77struct type50_meb2_msg {
 78	struct type50_hdr header;
 79	unsigned short	keyblock_type;	/* 0x0002 */
 80	unsigned char	reserved[6];
 81	unsigned char	exponent[256];
 82	unsigned char	modulus[256];
 83	unsigned char	message[256];
 84} __packed;
 85
 86/* Mod-Exp, with a larger modulus */
 87struct type50_meb3_msg {
 88	struct type50_hdr header;
 89	unsigned short	keyblock_type;	/* 0x0003 */
 90	unsigned char	reserved[6];
 91	unsigned char	exponent[512];
 92	unsigned char	modulus[512];
 93	unsigned char	message[512];
 94} __packed;
 95
 96/* CRT, with a small modulus */
 97struct type50_crb1_msg {
 98	struct type50_hdr header;
 99	unsigned short	keyblock_type;	/* 0x0011 */
100	unsigned char	reserved[6];
101	unsigned char	p[64];
102	unsigned char	q[64];
103	unsigned char	dp[64];
104	unsigned char	dq[64];
105	unsigned char	u[64];
106	unsigned char	message[128];
107} __packed;
108
109/* CRT, with a large modulus */
110struct type50_crb2_msg {
111	struct type50_hdr header;
112	unsigned short	keyblock_type;	/* 0x0012 */
113	unsigned char	reserved[6];
114	unsigned char	p[128];
115	unsigned char	q[128];
116	unsigned char	dp[128];
117	unsigned char	dq[128];
118	unsigned char	u[128];
119	unsigned char	message[256];
120} __packed;
121
122/* CRT, with a larger modulus */
123struct type50_crb3_msg {
124	struct type50_hdr header;
125	unsigned short	keyblock_type;	/* 0x0013 */
126	unsigned char	reserved[6];
127	unsigned char	p[256];
128	unsigned char	q[256];
129	unsigned char	dp[256];
130	unsigned char	dq[256];
131	unsigned char	u[256];
132	unsigned char	message[512];
133} __packed;
134
135/*
136 * The type 80 response family is associated with a CEXxA cards.
137 *
138 * Note that all unsigned char arrays are right-justified and left-padded
139 * with zeroes.
140 *
141 * Note that all reserved fields must be zeroes.
142 */
143
144#define TYPE80_RSP_CODE 0x80
145
146struct type80_hdr {
147	unsigned char	reserved1;
148	unsigned char	type;		/* 0x80 */
149	unsigned short	len;
150	unsigned char	code;		/* 0x00 */
151	unsigned char	reserved2[3];
152	unsigned char	reserved3[8];
153} __packed;
154
155int get_rsa_modex_fc(struct ica_rsa_modexpo *mex, int *fcode)
156{
157	if (!mex->inputdatalength)
158		return -EINVAL;
159
160	if (mex->inputdatalength <= 128)	/* 1024 bit */
161		*fcode = MEX_1K;
162	else if (mex->inputdatalength <= 256)	/* 2048 bit */
163		*fcode = MEX_2K;
164	else					/* 4096 bit */
165		*fcode = MEX_4K;
166
167	return 0;
168}
169
170int get_rsa_crt_fc(struct ica_rsa_modexpo_crt *crt, int *fcode)
171{
172	if (!crt->inputdatalength)
173		return -EINVAL;
174
175	if (crt->inputdatalength <= 128)	/* 1024 bit */
176		*fcode = CRT_1K;
177	else if (crt->inputdatalength <= 256)	/* 2048 bit */
178		*fcode = CRT_2K;
179	else					/* 4096 bit */
180		*fcode = CRT_4K;
181
182	return 0;
183}
184
185/*
186 * Convert a ICAMEX message to a type50 MEX message.
187 *
188 * @zq: crypto queue pointer
189 * @ap_msg: crypto request pointer
190 * @mex: pointer to user input data
191 *
192 * Returns 0 on success or -EFAULT.
193 */
194static int ICAMEX_msg_to_type50MEX_msg(struct zcrypt_queue *zq,
195				       struct ap_message *ap_msg,
196				       struct ica_rsa_modexpo *mex)
197{
198	unsigned char *mod, *exp, *inp;
199	int mod_len;
200
201	mod_len = mex->inputdatalength;
202
203	if (mod_len <= 128) {
204		struct type50_meb1_msg *meb1 = ap_msg->msg;
205
206		memset(meb1, 0, sizeof(*meb1));
207		ap_msg->len = sizeof(*meb1);
208		meb1->header.msg_type_code = TYPE50_TYPE_CODE;
209		meb1->header.msg_len = sizeof(*meb1);
210		meb1->keyblock_type = TYPE50_MEB1_FMT;
211		mod = meb1->modulus + sizeof(meb1->modulus) - mod_len;
212		exp = meb1->exponent + sizeof(meb1->exponent) - mod_len;
213		inp = meb1->message + sizeof(meb1->message) - mod_len;
214	} else if (mod_len <= 256) {
215		struct type50_meb2_msg *meb2 = ap_msg->msg;
216
217		memset(meb2, 0, sizeof(*meb2));
218		ap_msg->len = sizeof(*meb2);
219		meb2->header.msg_type_code = TYPE50_TYPE_CODE;
220		meb2->header.msg_len = sizeof(*meb2);
221		meb2->keyblock_type = TYPE50_MEB2_FMT;
222		mod = meb2->modulus + sizeof(meb2->modulus) - mod_len;
223		exp = meb2->exponent + sizeof(meb2->exponent) - mod_len;
224		inp = meb2->message + sizeof(meb2->message) - mod_len;
225	} else if (mod_len <= 512) {
226		struct type50_meb3_msg *meb3 = ap_msg->msg;
227
228		memset(meb3, 0, sizeof(*meb3));
229		ap_msg->len = sizeof(*meb3);
230		meb3->header.msg_type_code = TYPE50_TYPE_CODE;
231		meb3->header.msg_len = sizeof(*meb3);
232		meb3->keyblock_type = TYPE50_MEB3_FMT;
233		mod = meb3->modulus + sizeof(meb3->modulus) - mod_len;
234		exp = meb3->exponent + sizeof(meb3->exponent) - mod_len;
235		inp = meb3->message + sizeof(meb3->message) - mod_len;
236	} else {
237		return -EINVAL;
238	}
239
240	if (copy_from_user(mod, mex->n_modulus, mod_len) ||
241	    copy_from_user(exp, mex->b_key, mod_len) ||
242	    copy_from_user(inp, mex->inputdata, mod_len))
243		return -EFAULT;
244
245	return 0;
246}
247
248/*
249 * Convert a ICACRT message to a type50 CRT message.
250 *
251 * @zq: crypto queue pointer
252 * @ap_msg: crypto request pointer
253 * @crt: pointer to user input data
254 *
255 * Returns 0 on success or -EFAULT.
256 */
257static int ICACRT_msg_to_type50CRT_msg(struct zcrypt_queue *zq,
258				       struct ap_message *ap_msg,
259				       struct ica_rsa_modexpo_crt *crt)
260{
261	int mod_len, short_len;
262	unsigned char *p, *q, *dp, *dq, *u, *inp;
263
264	mod_len = crt->inputdatalength;
265	short_len = (mod_len + 1) / 2;
266
267	/*
268	 * CEX2A and CEX3A w/o FW update can handle requests up to
269	 * 256 byte modulus (2k keys).
270	 * CEX3A with FW update and newer CEXxA cards are able to handle
271	 * 512 byte modulus (4k keys).
272	 */
273	if (mod_len <= 128) {		/* up to 1024 bit key size */
274		struct type50_crb1_msg *crb1 = ap_msg->msg;
275
276		memset(crb1, 0, sizeof(*crb1));
277		ap_msg->len = sizeof(*crb1);
278		crb1->header.msg_type_code = TYPE50_TYPE_CODE;
279		crb1->header.msg_len = sizeof(*crb1);
280		crb1->keyblock_type = TYPE50_CRB1_FMT;
281		p = crb1->p + sizeof(crb1->p) - short_len;
282		q = crb1->q + sizeof(crb1->q) - short_len;
283		dp = crb1->dp + sizeof(crb1->dp) - short_len;
284		dq = crb1->dq + sizeof(crb1->dq) - short_len;
285		u = crb1->u + sizeof(crb1->u) - short_len;
286		inp = crb1->message + sizeof(crb1->message) - mod_len;
287	} else if (mod_len <= 256) {	/* up to 2048 bit key size */
288		struct type50_crb2_msg *crb2 = ap_msg->msg;
289
290		memset(crb2, 0, sizeof(*crb2));
291		ap_msg->len = sizeof(*crb2);
292		crb2->header.msg_type_code = TYPE50_TYPE_CODE;
293		crb2->header.msg_len = sizeof(*crb2);
294		crb2->keyblock_type = TYPE50_CRB2_FMT;
295		p = crb2->p + sizeof(crb2->p) - short_len;
296		q = crb2->q + sizeof(crb2->q) - short_len;
297		dp = crb2->dp + sizeof(crb2->dp) - short_len;
298		dq = crb2->dq + sizeof(crb2->dq) - short_len;
299		u = crb2->u + sizeof(crb2->u) - short_len;
300		inp = crb2->message + sizeof(crb2->message) - mod_len;
301	} else if ((mod_len <= 512) &&	/* up to 4096 bit key size */
302		   (zq->zcard->max_mod_size == CEX3A_MAX_MOD_SIZE)) {
303		struct type50_crb3_msg *crb3 = ap_msg->msg;
304
305		memset(crb3, 0, sizeof(*crb3));
306		ap_msg->len = sizeof(*crb3);
307		crb3->header.msg_type_code = TYPE50_TYPE_CODE;
308		crb3->header.msg_len = sizeof(*crb3);
309		crb3->keyblock_type = TYPE50_CRB3_FMT;
310		p = crb3->p + sizeof(crb3->p) - short_len;
311		q = crb3->q + sizeof(crb3->q) - short_len;
312		dp = crb3->dp + sizeof(crb3->dp) - short_len;
313		dq = crb3->dq + sizeof(crb3->dq) - short_len;
314		u = crb3->u + sizeof(crb3->u) - short_len;
315		inp = crb3->message + sizeof(crb3->message) - mod_len;
316	} else {
317		return -EINVAL;
318	}
319
320	/*
321	 * correct the offset of p, bp and mult_inv according zcrypt.h
322	 * block size right aligned (skip the first byte)
323	 */
324	if (copy_from_user(p, crt->np_prime + MSGTYPE_ADJUSTMENT, short_len) ||
325	    copy_from_user(q, crt->nq_prime, short_len) ||
326	    copy_from_user(dp, crt->bp_key + MSGTYPE_ADJUSTMENT, short_len) ||
327	    copy_from_user(dq, crt->bq_key, short_len) ||
328	    copy_from_user(u, crt->u_mult_inv + MSGTYPE_ADJUSTMENT, short_len) ||
329	    copy_from_user(inp, crt->inputdata, mod_len))
330		return -EFAULT;
331
332	return 0;
333}
334
335/*
336 * Copy results from a type 80 reply message back to user space.
337 *
338 * @zq: crypto device pointer
339 * @reply: reply AP message.
340 * @data: pointer to user output data
341 * @length: size of user output data
342 *
343 * Returns 0 on success or -EFAULT.
344 */
345static int convert_type80(struct zcrypt_queue *zq,
346			  struct ap_message *reply,
347			  char __user *outputdata,
348			  unsigned int outputdatalength)
349{
350	struct type80_hdr *t80h = reply->msg;
351	unsigned char *data;
352
353	if (t80h->len < sizeof(*t80h) + outputdatalength) {
354		/* The result is too short, the CEXxA card may not do that.. */
355		zq->online = 0;
356		pr_err("Crypto dev=%02x.%04x code=0x%02x => online=0 rc=EAGAIN\n",
357		       AP_QID_CARD(zq->queue->qid),
358		       AP_QID_QUEUE(zq->queue->qid), t80h->code);
359		ZCRYPT_DBF_ERR("%s dev=%02x.%04x code=0x%02x => online=0 rc=EAGAIN\n",
360			       __func__, AP_QID_CARD(zq->queue->qid),
361			       AP_QID_QUEUE(zq->queue->qid), t80h->code);
362		ap_send_online_uevent(&zq->queue->ap_dev, zq->online);
363		return -EAGAIN;
364	}
365	BUG_ON(t80h->len > CEX3A_MAX_RESPONSE_SIZE);
366	data = reply->msg + t80h->len - outputdatalength;
367	if (copy_to_user(outputdata, data, outputdatalength))
368		return -EFAULT;
369	return 0;
370}
371
372static int convert_response(struct zcrypt_queue *zq,
373			    struct ap_message *reply,
374			    char __user *outputdata,
375			    unsigned int outputdatalength)
376{
377	/* Response type byte is the second byte in the response. */
378	unsigned char rtype = ((unsigned char *)reply->msg)[1];
379
380	switch (rtype) {
381	case TYPE82_RSP_CODE:
382	case TYPE88_RSP_CODE:
383		return convert_error(zq, reply);
384	case TYPE80_RSP_CODE:
385		return convert_type80(zq, reply,
386				      outputdata, outputdatalength);
387	default: /* Unknown response type, this should NEVER EVER happen */
388		zq->online = 0;
389		pr_err("Crypto dev=%02x.%04x unknown response type 0x%02x => online=0 rc=EAGAIN\n",
390		       AP_QID_CARD(zq->queue->qid),
391		       AP_QID_QUEUE(zq->queue->qid),
392		       (int)rtype);
393		ZCRYPT_DBF_ERR(
394			"%s dev=%02x.%04x unknown response type 0x%02x => online=0 rc=EAGAIN\n",
395			__func__, AP_QID_CARD(zq->queue->qid),
396			AP_QID_QUEUE(zq->queue->qid), (int)rtype);
397		ap_send_online_uevent(&zq->queue->ap_dev, zq->online);
398		return -EAGAIN;
399	}
400}
401
402/*
403 * This function is called from the AP bus code after a crypto request
404 * "msg" has finished with the reply message "reply".
405 * It is called from tasklet context.
406 * @aq: pointer to the AP device
407 * @msg: pointer to the AP message
408 * @reply: pointer to the AP reply message
409 */
410static void zcrypt_msgtype50_receive(struct ap_queue *aq,
411				     struct ap_message *msg,
412				     struct ap_message *reply)
413{
414	static struct error_hdr error_reply = {
415		.type = TYPE82_RSP_CODE,
416		.reply_code = REP82_ERROR_MACHINE_FAILURE,
417	};
418	struct type80_hdr *t80h;
419	int len;
420
421	/* Copy the reply message to the request message buffer. */
422	if (!reply)
423		goto out;	/* ap_msg->rc indicates the error */
424	t80h = reply->msg;
425	if (t80h->type == TYPE80_RSP_CODE) {
426		len = t80h->len;
427		if (len > reply->bufsize || len > msg->bufsize ||
428		    len != reply->len) {
429			pr_debug("len mismatch => EMSGSIZE\n");
430			msg->rc = -EMSGSIZE;
431			goto out;
432		}
433		memcpy(msg->msg, reply->msg, len);
434		msg->len = len;
435	} else {
436		memcpy(msg->msg, reply->msg, sizeof(error_reply));
437		msg->len = sizeof(error_reply);
438	}
439out:
440	complete(&msg->response.work);
441}
442
443static atomic_t zcrypt_step = ATOMIC_INIT(0);
444
445/*
446 * The request distributor calls this function if it picked the CEXxA
447 * device to handle a modexpo request.
448 * @zq: pointer to zcrypt_queue structure that identifies the
449 *	CEXxA device to the request distributor
450 * @mex: pointer to the modexpo request buffer
451 * This function assumes that ap_msg has been initialized with
452 * ap_init_apmsg() and thus a valid buffer with the size of
453 * ap_msg->bufsize is available within ap_msg. Also the caller has
454 * to make sure ap_release_apmsg() is always called even on failure.
455 */
456static long zcrypt_msgtype50_modexpo(struct zcrypt_queue *zq,
457				     struct ica_rsa_modexpo *mex,
458				     struct ap_message *ap_msg)
459{
460	int rc;
461
462	if (ap_msg->bufsize < MSGTYPE50_CRB3_MAX_MSG_SIZE)
463		return -EMSGSIZE;
464	ap_msg->receive = zcrypt_msgtype50_receive;
465	ap_msg->psmid = (((unsigned long)current->pid) << 32) +
466		atomic_inc_return(&zcrypt_step);
467	rc = ICAMEX_msg_to_type50MEX_msg(zq, ap_msg, mex);
468	if (rc)
469		goto out;
470	init_completion(&ap_msg->response.work);
471	rc = ap_queue_message(zq->queue, ap_msg);
472	if (rc)
473		goto out;
474	rc = wait_for_completion_interruptible(&ap_msg->response.work);
475	if (rc == 0) {
476		rc = ap_msg->rc;
477		if (rc == 0)
478			rc = convert_response(zq, ap_msg,
479					      mex->outputdata,
480					      mex->outputdatalength);
481	} else {
482		/* Signal pending. */
483		ap_cancel_message(zq->queue, ap_msg);
484	}
485
486out:
487	if (rc)
488		pr_debug("send me cprb at dev=%02x.%04x rc=%d\n",
489			 AP_QID_CARD(zq->queue->qid),
490			 AP_QID_QUEUE(zq->queue->qid), rc);
491	return rc;
492}
493
494/*
495 * The request distributor calls this function if it picked the CEXxA
496 * device to handle a modexpo_crt request.
497 * @zq: pointer to zcrypt_queue structure that identifies the
498 *	CEXxA device to the request distributor
499 * @crt: pointer to the modexpoc_crt request buffer
500 * This function assumes that ap_msg has been initialized with
501 * ap_init_apmsg() and thus a valid buffer with the size of
502 * ap_msg->bufsize is available within ap_msg. Also the caller has
503 * to make sure ap_release_apmsg() is always called even on failure.
504 */
505static long zcrypt_msgtype50_modexpo_crt(struct zcrypt_queue *zq,
506					 struct ica_rsa_modexpo_crt *crt,
507					 struct ap_message *ap_msg)
508{
509	int rc;
510
511	if (ap_msg->bufsize < MSGTYPE50_CRB3_MAX_MSG_SIZE)
512		return -EMSGSIZE;
513	ap_msg->receive = zcrypt_msgtype50_receive;
514	ap_msg->psmid = (((unsigned long)current->pid) << 32) +
515		atomic_inc_return(&zcrypt_step);
516	rc = ICACRT_msg_to_type50CRT_msg(zq, ap_msg, crt);
517	if (rc)
518		goto out;
519	init_completion(&ap_msg->response.work);
520	rc = ap_queue_message(zq->queue, ap_msg);
521	if (rc)
522		goto out;
523	rc = wait_for_completion_interruptible(&ap_msg->response.work);
524	if (rc == 0) {
525		rc = ap_msg->rc;
526		if (rc == 0)
527			rc = convert_response(zq, ap_msg,
528					      crt->outputdata,
529					      crt->outputdatalength);
530	} else {
531		/* Signal pending. */
532		ap_cancel_message(zq->queue, ap_msg);
533	}
534
535out:
536	if (rc)
537		pr_debug("send crt cprb at dev=%02x.%04x rc=%d\n",
538			 AP_QID_CARD(zq->queue->qid),
539			 AP_QID_QUEUE(zq->queue->qid), rc);
540	return rc;
541}
542
543/*
544 * The crypto operations for message type 50.
545 */
546static struct zcrypt_ops zcrypt_msgtype50_ops = {
547	.rsa_modexpo = zcrypt_msgtype50_modexpo,
548	.rsa_modexpo_crt = zcrypt_msgtype50_modexpo_crt,
549	.owner = THIS_MODULE,
550	.name = MSGTYPE50_NAME,
551	.variant = MSGTYPE50_VARIANT_DEFAULT,
552};
553
554void __init zcrypt_msgtype50_init(void)
555{
556	zcrypt_msgtype_register(&zcrypt_msgtype50_ops);
557}
558
559void __exit zcrypt_msgtype50_exit(void)
560{
561	zcrypt_msgtype_unregister(&zcrypt_msgtype50_ops);
562}