xref: /openbmc/linux/drivers/crypto/bcm/util.c (revision a20eefae)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright 2016 Broadcom
4  */
5 
6 #include <linux/debugfs.h>
7 
8 #include "cipher.h"
9 #include "util.h"
10 
11 /* offset of SPU_OFIFO_CTRL register */
12 #define SPU_OFIFO_CTRL      0x40
13 #define SPU_FIFO_WATERMARK  0x1FF
14 
15 /**
16  * spu_sg_at_offset() - Find the scatterlist entry at a given distance from the
17  * start of a scatterlist.
18  * @sg:         [in]  Start of a scatterlist
19  * @skip:       [in]  Distance from the start of the scatterlist, in bytes
20  * @sge:        [out] Scatterlist entry at skip bytes from start
21  * @sge_offset: [out] Number of bytes from start of sge buffer to get to
22  *                    requested distance.
23  *
24  * Return: 0 if entry found at requested distance
25  *         < 0 otherwise
26  */
27 int spu_sg_at_offset(struct scatterlist *sg, unsigned int skip,
28 		     struct scatterlist **sge, unsigned int *sge_offset)
29 {
30 	/* byte index from start of sg to the end of the previous entry */
31 	unsigned int index = 0;
32 	/* byte index from start of sg to the end of the current entry */
33 	unsigned int next_index;
34 
35 	next_index = sg->length;
36 	while (next_index <= skip) {
37 		sg = sg_next(sg);
38 		index = next_index;
39 		if (!sg)
40 			return -EINVAL;
41 		next_index += sg->length;
42 	}
43 
44 	*sge_offset = skip - index;
45 	*sge = sg;
46 	return 0;
47 }
48 
49 /* Copy len bytes of sg data, starting at offset skip, to a dest buffer */
50 void sg_copy_part_to_buf(struct scatterlist *src, u8 *dest,
51 			 unsigned int len, unsigned int skip)
52 {
53 	size_t copied;
54 	unsigned int nents = sg_nents(src);
55 
56 	copied = sg_pcopy_to_buffer(src, nents, dest, len, skip);
57 	if (copied != len) {
58 		flow_log("%s copied %u bytes of %u requested. ",
59 			 __func__, (u32)copied, len);
60 		flow_log("sg with %u entries and skip %u\n", nents, skip);
61 	}
62 }
63 
64 /*
65  * Copy data into a scatterlist starting at a specified offset in the
66  * scatterlist. Specifically, copy len bytes of data in the buffer src
67  * into the scatterlist dest, starting skip bytes into the scatterlist.
68  */
69 void sg_copy_part_from_buf(struct scatterlist *dest, u8 *src,
70 			   unsigned int len, unsigned int skip)
71 {
72 	size_t copied;
73 	unsigned int nents = sg_nents(dest);
74 
75 	copied = sg_pcopy_from_buffer(dest, nents, src, len, skip);
76 	if (copied != len) {
77 		flow_log("%s copied %u bytes of %u requested. ",
78 			 __func__, (u32)copied, len);
79 		flow_log("sg with %u entries and skip %u\n", nents, skip);
80 	}
81 }
82 
83 /**
84  * spu_sg_count() - Determine number of elements in scatterlist to provide a
85  * specified number of bytes.
86  * @sg_list:  scatterlist to examine
87  * @skip:     index of starting point
88  * @nbytes:   consider elements of scatterlist until reaching this number of
89  *	      bytes
90  *
91  * Return: the number of sg entries contributing to nbytes of data
92  */
93 int spu_sg_count(struct scatterlist *sg_list, unsigned int skip, int nbytes)
94 {
95 	struct scatterlist *sg;
96 	int sg_nents = 0;
97 	unsigned int offset;
98 
99 	if (!sg_list)
100 		return 0;
101 
102 	if (spu_sg_at_offset(sg_list, skip, &sg, &offset) < 0)
103 		return 0;
104 
105 	while (sg && (nbytes > 0)) {
106 		sg_nents++;
107 		nbytes -= (sg->length - offset);
108 		offset = 0;
109 		sg = sg_next(sg);
110 	}
111 	return sg_nents;
112 }
113 
114 /**
115  * spu_msg_sg_add() - Copy scatterlist entries from one sg to another, up to a
116  * given length.
117  * @to_sg:       scatterlist to copy to
118  * @from_sg:     scatterlist to copy from
119  * @from_skip:   number of bytes to skip in from_sg. Non-zero when previous
120  *		 request included part of the buffer in entry in from_sg.
121  *		 Assumes from_skip < from_sg->length.
122  * @from_nents   number of entries in from_sg
123  * @length       number of bytes to copy. may reach this limit before exhausting
124  *		 from_sg.
125  *
126  * Copies the entries themselves, not the data in the entries. Assumes to_sg has
127  * enough entries. Does not limit the size of an individual buffer in to_sg.
128  *
129  * to_sg, from_sg, skip are all updated to end of copy
130  *
131  * Return: Number of bytes copied
132  */
133 u32 spu_msg_sg_add(struct scatterlist **to_sg,
134 		   struct scatterlist **from_sg, u32 *from_skip,
135 		   u8 from_nents, u32 length)
136 {
137 	struct scatterlist *sg;	/* an entry in from_sg */
138 	struct scatterlist *to = *to_sg;
139 	struct scatterlist *from = *from_sg;
140 	u32 skip = *from_skip;
141 	u32 offset;
142 	int i;
143 	u32 entry_len = 0;
144 	u32 frag_len = 0;	/* length of entry added to to_sg */
145 	u32 copied = 0;		/* number of bytes copied so far */
146 
147 	if (length == 0)
148 		return 0;
149 
150 	for_each_sg(from, sg, from_nents, i) {
151 		/* number of bytes in this from entry not yet used */
152 		entry_len = sg->length - skip;
153 		frag_len = min(entry_len, length - copied);
154 		offset = sg->offset + skip;
155 		if (frag_len)
156 			sg_set_page(to++, sg_page(sg), frag_len, offset);
157 		copied += frag_len;
158 		if (copied == entry_len) {
159 			/* used up all of from entry */
160 			skip = 0;	/* start at beginning of next entry */
161 		}
162 		if (copied == length)
163 			break;
164 	}
165 	*to_sg = to;
166 	*from_sg = sg;
167 	if (frag_len < entry_len)
168 		*from_skip = skip + frag_len;
169 	else
170 		*from_skip = 0;
171 
172 	return copied;
173 }
174 
175 void add_to_ctr(u8 *ctr_pos, unsigned int increment)
176 {
177 	__be64 *high_be = (__be64 *)ctr_pos;
178 	__be64 *low_be = high_be + 1;
179 	u64 orig_low = __be64_to_cpu(*low_be);
180 	u64 new_low = orig_low + (u64)increment;
181 
182 	*low_be = __cpu_to_be64(new_low);
183 	if (new_low < orig_low)
184 		/* there was a carry from the low 8 bytes */
185 		*high_be = __cpu_to_be64(__be64_to_cpu(*high_be) + 1);
186 }
187 
188 struct sdesc {
189 	struct shash_desc shash;
190 	char ctx[];
191 };
192 
193 /**
194  * do_shash() - Do a synchronous hash operation in software
195  * @name:       The name of the hash algorithm
196  * @result:     Buffer where digest is to be written
197  * @data1:      First part of data to hash. May be NULL.
198  * @data1_len:  Length of data1, in bytes
199  * @data2:      Second part of data to hash. May be NULL.
200  * @data2_len:  Length of data2, in bytes
201  * @key:	Key (if keyed hash)
202  * @key_len:	Length of key, in bytes (or 0 if non-keyed hash)
203  *
204  * Note that the crypto API will not select this driver's own transform because
205  * this driver only registers asynchronous algos.
206  *
207  * Return: 0 if hash successfully stored in result
208  *         < 0 otherwise
209  */
210 int do_shash(unsigned char *name, unsigned char *result,
211 	     const u8 *data1, unsigned int data1_len,
212 	     const u8 *data2, unsigned int data2_len,
213 	     const u8 *key, unsigned int key_len)
214 {
215 	int rc;
216 	unsigned int size;
217 	struct crypto_shash *hash;
218 	struct sdesc *sdesc;
219 
220 	hash = crypto_alloc_shash(name, 0, 0);
221 	if (IS_ERR(hash)) {
222 		rc = PTR_ERR(hash);
223 		pr_err("%s: Crypto %s allocation error %d\n", __func__, name, rc);
224 		return rc;
225 	}
226 
227 	size = sizeof(struct shash_desc) + crypto_shash_descsize(hash);
228 	sdesc = kmalloc(size, GFP_KERNEL);
229 	if (!sdesc) {
230 		rc = -ENOMEM;
231 		goto do_shash_err;
232 	}
233 	sdesc->shash.tfm = hash;
234 
235 	if (key_len > 0) {
236 		rc = crypto_shash_setkey(hash, key, key_len);
237 		if (rc) {
238 			pr_err("%s: Could not setkey %s shash\n", __func__, name);
239 			goto do_shash_err;
240 		}
241 	}
242 
243 	rc = crypto_shash_init(&sdesc->shash);
244 	if (rc) {
245 		pr_err("%s: Could not init %s shash\n", __func__, name);
246 		goto do_shash_err;
247 	}
248 	rc = crypto_shash_update(&sdesc->shash, data1, data1_len);
249 	if (rc) {
250 		pr_err("%s: Could not update1\n", __func__);
251 		goto do_shash_err;
252 	}
253 	if (data2 && data2_len) {
254 		rc = crypto_shash_update(&sdesc->shash, data2, data2_len);
255 		if (rc) {
256 			pr_err("%s: Could not update2\n", __func__);
257 			goto do_shash_err;
258 		}
259 	}
260 	rc = crypto_shash_final(&sdesc->shash, result);
261 	if (rc)
262 		pr_err("%s: Could not generate %s hash\n", __func__, name);
263 
264 do_shash_err:
265 	crypto_free_shash(hash);
266 	kfree(sdesc);
267 
268 	return rc;
269 }
270 
271 /* Dump len bytes of a scatterlist starting at skip bytes into the sg */
272 void __dump_sg(struct scatterlist *sg, unsigned int skip, unsigned int len)
273 {
274 	u8 dbuf[16];
275 	unsigned int idx = skip;
276 	unsigned int num_out = 0;	/* number of bytes dumped so far */
277 	unsigned int count;
278 
279 	if (packet_debug_logging) {
280 		while (num_out < len) {
281 			count = (len - num_out > 16) ? 16 : len - num_out;
282 			sg_copy_part_to_buf(sg, dbuf, count, idx);
283 			num_out += count;
284 			print_hex_dump(KERN_ALERT, "  sg: ", DUMP_PREFIX_NONE,
285 				       4, 1, dbuf, count, false);
286 			idx += 16;
287 		}
288 	}
289 	if (debug_logging_sleep)
290 		msleep(debug_logging_sleep);
291 }
292 
293 /* Returns the name for a given cipher alg/mode */
294 char *spu_alg_name(enum spu_cipher_alg alg, enum spu_cipher_mode mode)
295 {
296 	switch (alg) {
297 	case CIPHER_ALG_RC4:
298 		return "rc4";
299 	case CIPHER_ALG_AES:
300 		switch (mode) {
301 		case CIPHER_MODE_CBC:
302 			return "cbc(aes)";
303 		case CIPHER_MODE_ECB:
304 			return "ecb(aes)";
305 		case CIPHER_MODE_OFB:
306 			return "ofb(aes)";
307 		case CIPHER_MODE_CFB:
308 			return "cfb(aes)";
309 		case CIPHER_MODE_CTR:
310 			return "ctr(aes)";
311 		case CIPHER_MODE_XTS:
312 			return "xts(aes)";
313 		case CIPHER_MODE_GCM:
314 			return "gcm(aes)";
315 		default:
316 			return "aes";
317 		}
318 		break;
319 	case CIPHER_ALG_DES:
320 		switch (mode) {
321 		case CIPHER_MODE_CBC:
322 			return "cbc(des)";
323 		case CIPHER_MODE_ECB:
324 			return "ecb(des)";
325 		case CIPHER_MODE_CTR:
326 			return "ctr(des)";
327 		default:
328 			return "des";
329 		}
330 		break;
331 	case CIPHER_ALG_3DES:
332 		switch (mode) {
333 		case CIPHER_MODE_CBC:
334 			return "cbc(des3_ede)";
335 		case CIPHER_MODE_ECB:
336 			return "ecb(des3_ede)";
337 		case CIPHER_MODE_CTR:
338 			return "ctr(des3_ede)";
339 		default:
340 			return "3des";
341 		}
342 		break;
343 	default:
344 		return "other";
345 	}
346 }
347 
348 static ssize_t spu_debugfs_read(struct file *filp, char __user *ubuf,
349 				size_t count, loff_t *offp)
350 {
351 	struct device_private *ipriv;
352 	char *buf;
353 	ssize_t ret, out_offset, out_count;
354 	int i;
355 	u32 fifo_len;
356 	u32 spu_ofifo_ctrl;
357 	u32 alg;
358 	u32 mode;
359 	u32 op_cnt;
360 
361 	out_count = 2048;
362 
363 	buf = kmalloc(out_count, GFP_KERNEL);
364 	if (!buf)
365 		return -ENOMEM;
366 
367 	ipriv = filp->private_data;
368 	out_offset = 0;
369 	out_offset += snprintf(buf + out_offset, out_count - out_offset,
370 			       "Number of SPUs.........%u\n",
371 			       ipriv->spu.num_spu);
372 	out_offset += snprintf(buf + out_offset, out_count - out_offset,
373 			       "Current sessions.......%u\n",
374 			       atomic_read(&ipriv->session_count));
375 	out_offset += snprintf(buf + out_offset, out_count - out_offset,
376 			       "Session count..........%u\n",
377 			       atomic_read(&ipriv->stream_count));
378 	out_offset += snprintf(buf + out_offset, out_count - out_offset,
379 			       "Cipher setkey..........%u\n",
380 			       atomic_read(&ipriv->setkey_cnt[SPU_OP_CIPHER]));
381 	out_offset += snprintf(buf + out_offset, out_count - out_offset,
382 			       "Cipher Ops.............%u\n",
383 			       atomic_read(&ipriv->op_counts[SPU_OP_CIPHER]));
384 	for (alg = 0; alg < CIPHER_ALG_LAST; alg++) {
385 		for (mode = 0; mode < CIPHER_MODE_LAST; mode++) {
386 			op_cnt = atomic_read(&ipriv->cipher_cnt[alg][mode]);
387 			if (op_cnt) {
388 				out_offset += snprintf(buf + out_offset,
389 						       out_count - out_offset,
390 			       "  %-13s%11u\n",
391 			       spu_alg_name(alg, mode), op_cnt);
392 			}
393 		}
394 	}
395 	out_offset += snprintf(buf + out_offset, out_count - out_offset,
396 			       "Hash Ops...............%u\n",
397 			       atomic_read(&ipriv->op_counts[SPU_OP_HASH]));
398 	for (alg = 0; alg < HASH_ALG_LAST; alg++) {
399 		op_cnt = atomic_read(&ipriv->hash_cnt[alg]);
400 		if (op_cnt) {
401 			out_offset += snprintf(buf + out_offset,
402 					       out_count - out_offset,
403 		       "  %-13s%11u\n",
404 		       hash_alg_name[alg], op_cnt);
405 		}
406 	}
407 	out_offset += snprintf(buf + out_offset, out_count - out_offset,
408 			       "HMAC setkey............%u\n",
409 			       atomic_read(&ipriv->setkey_cnt[SPU_OP_HMAC]));
410 	out_offset += snprintf(buf + out_offset, out_count - out_offset,
411 			       "HMAC Ops...............%u\n",
412 			       atomic_read(&ipriv->op_counts[SPU_OP_HMAC]));
413 	for (alg = 0; alg < HASH_ALG_LAST; alg++) {
414 		op_cnt = atomic_read(&ipriv->hmac_cnt[alg]);
415 		if (op_cnt) {
416 			out_offset += snprintf(buf + out_offset,
417 					       out_count - out_offset,
418 		       "  %-13s%11u\n",
419 		       hash_alg_name[alg], op_cnt);
420 		}
421 	}
422 	out_offset += snprintf(buf + out_offset, out_count - out_offset,
423 			       "AEAD setkey............%u\n",
424 			       atomic_read(&ipriv->setkey_cnt[SPU_OP_AEAD]));
425 
426 	out_offset += snprintf(buf + out_offset, out_count - out_offset,
427 			       "AEAD Ops...............%u\n",
428 			       atomic_read(&ipriv->op_counts[SPU_OP_AEAD]));
429 	for (alg = 0; alg < AEAD_TYPE_LAST; alg++) {
430 		op_cnt = atomic_read(&ipriv->aead_cnt[alg]);
431 		if (op_cnt) {
432 			out_offset += snprintf(buf + out_offset,
433 					       out_count - out_offset,
434 		       "  %-13s%11u\n",
435 		       aead_alg_name[alg], op_cnt);
436 		}
437 	}
438 	out_offset += snprintf(buf + out_offset, out_count - out_offset,
439 			       "Bytes of req data......%llu\n",
440 			       (u64)atomic64_read(&ipriv->bytes_out));
441 	out_offset += snprintf(buf + out_offset, out_count - out_offset,
442 			       "Bytes of resp data.....%llu\n",
443 			       (u64)atomic64_read(&ipriv->bytes_in));
444 	out_offset += snprintf(buf + out_offset, out_count - out_offset,
445 			       "Mailbox full...........%u\n",
446 			       atomic_read(&ipriv->mb_no_spc));
447 	out_offset += snprintf(buf + out_offset, out_count - out_offset,
448 			       "Mailbox send failures..%u\n",
449 			       atomic_read(&ipriv->mb_send_fail));
450 	out_offset += snprintf(buf + out_offset, out_count - out_offset,
451 			       "Check ICV errors.......%u\n",
452 			       atomic_read(&ipriv->bad_icv));
453 	if (ipriv->spu.spu_type == SPU_TYPE_SPUM)
454 		for (i = 0; i < ipriv->spu.num_spu; i++) {
455 			spu_ofifo_ctrl = ioread32(ipriv->spu.reg_vbase[i] +
456 						  SPU_OFIFO_CTRL);
457 			fifo_len = spu_ofifo_ctrl & SPU_FIFO_WATERMARK;
458 			out_offset += snprintf(buf + out_offset,
459 					       out_count - out_offset,
460 				       "SPU %d output FIFO high water.....%u\n",
461 				       i, fifo_len);
462 		}
463 
464 	if (out_offset > out_count)
465 		out_offset = out_count;
466 
467 	ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset);
468 	kfree(buf);
469 	return ret;
470 }
471 
472 static const struct file_operations spu_debugfs_stats = {
473 	.owner = THIS_MODULE,
474 	.open = simple_open,
475 	.read = spu_debugfs_read,
476 };
477 
478 /*
479  * Create the debug FS directories. If the top-level directory has not yet
480  * been created, create it now. Create a stats file in this directory for
481  * a SPU.
482  */
483 void spu_setup_debugfs(void)
484 {
485 	if (!debugfs_initialized())
486 		return;
487 
488 	if (!iproc_priv.debugfs_dir)
489 		iproc_priv.debugfs_dir = debugfs_create_dir(KBUILD_MODNAME,
490 							    NULL);
491 
492 	if (!iproc_priv.debugfs_stats)
493 		/* Create file with permissions S_IRUSR */
494 		debugfs_create_file("stats", 0400, iproc_priv.debugfs_dir,
495 				    &iproc_priv, &spu_debugfs_stats);
496 }
497 
498 void spu_free_debugfs(void)
499 {
500 	debugfs_remove_recursive(iproc_priv.debugfs_dir);
501 	iproc_priv.debugfs_dir = NULL;
502 }
503 
504 /**
505  * format_value_ccm() - Format a value into a buffer, using a specified number
506  *			of bytes (i.e. maybe writing value X into a 4 byte
507  *			buffer, or maybe into a 12 byte buffer), as per the
508  *			SPU CCM spec.
509  *
510  * @val:		value to write (up to max of unsigned int)
511  * @buf:		(pointer to) buffer to write the value
512  * @len:		number of bytes to use (0 to 255)
513  *
514  */
515 void format_value_ccm(unsigned int val, u8 *buf, u8 len)
516 {
517 	int i;
518 
519 	/* First clear full output buffer */
520 	memset(buf, 0, len);
521 
522 	/* Then, starting from right side, fill in with data */
523 	for (i = 0; i < len; i++) {
524 		buf[len - i - 1] = (val >> (8 * i)) & 0xff;
525 		if (i >= 3)
526 			break;  /* Only handle up to 32 bits of 'val' */
527 	}
528 }
529