xref: /openbmc/linux/drivers/crypto/bcm/spu.c (revision b8265621)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright 2016 Broadcom
4  */
5 
6 #include <linux/kernel.h>
7 #include <linux/string.h>
8 
9 #include "util.h"
10 #include "spu.h"
11 #include "spum.h"
12 #include "cipher.h"
13 
14 char *hash_alg_name[] = { "None", "md5", "sha1", "sha224", "sha256", "aes",
15 	"sha384", "sha512", "sha3_224", "sha3_256", "sha3_384", "sha3_512" };
16 
17 char *aead_alg_name[] = { "ccm(aes)", "gcm(aes)", "authenc" };
18 
19 /* Assumes SPU-M messages are in big endian */
20 void spum_dump_msg_hdr(u8 *buf, unsigned int buf_len)
21 {
22 	u8 *ptr = buf;
23 	struct SPUHEADER *spuh = (struct SPUHEADER *)buf;
24 	unsigned int hash_key_len = 0;
25 	unsigned int hash_state_len = 0;
26 	unsigned int cipher_key_len = 0;
27 	unsigned int iv_len;
28 	u32 pflags;
29 	u32 cflags;
30 	u32 ecf;
31 	u32 cipher_alg;
32 	u32 cipher_mode;
33 	u32 cipher_type;
34 	u32 hash_alg;
35 	u32 hash_mode;
36 	u32 hash_type;
37 	u32 sctx_size;   /* SCTX length in words */
38 	u32 sctx_pl_len; /* SCTX payload length in bytes */
39 
40 	packet_log("\n");
41 	packet_log("SPU Message header %p len: %u\n", buf, buf_len);
42 
43 	/* ========== Decode MH ========== */
44 	packet_log("  MH 0x%08x\n", be32_to_cpu(*((u32 *)ptr)));
45 	if (spuh->mh.flags & MH_SCTX_PRES)
46 		packet_log("    SCTX  present\n");
47 	if (spuh->mh.flags & MH_BDESC_PRES)
48 		packet_log("    BDESC present\n");
49 	if (spuh->mh.flags & MH_MFM_PRES)
50 		packet_log("    MFM   present\n");
51 	if (spuh->mh.flags & MH_BD_PRES)
52 		packet_log("    BD    present\n");
53 	if (spuh->mh.flags & MH_HASH_PRES)
54 		packet_log("    HASH  present\n");
55 	if (spuh->mh.flags & MH_SUPDT_PRES)
56 		packet_log("    SUPDT present\n");
57 	packet_log("    Opcode 0x%02x\n", spuh->mh.op_code);
58 
59 	ptr += sizeof(spuh->mh) + sizeof(spuh->emh);  /* skip emh. unused */
60 
61 	/* ========== Decode SCTX ========== */
62 	if (spuh->mh.flags & MH_SCTX_PRES) {
63 		pflags = be32_to_cpu(spuh->sa.proto_flags);
64 		packet_log("  SCTX[0] 0x%08x\n", pflags);
65 		sctx_size = pflags & SCTX_SIZE;
66 		packet_log("    Size %u words\n", sctx_size);
67 
68 		cflags = be32_to_cpu(spuh->sa.cipher_flags);
69 		packet_log("  SCTX[1] 0x%08x\n", cflags);
70 		packet_log("    Inbound:%lu (1:decrypt/vrfy 0:encrypt/auth)\n",
71 			   (cflags & CIPHER_INBOUND) >> CIPHER_INBOUND_SHIFT);
72 		packet_log("    Order:%lu (1:AuthFirst 0:EncFirst)\n",
73 			   (cflags & CIPHER_ORDER) >> CIPHER_ORDER_SHIFT);
74 		packet_log("    ICV_IS_512:%lx\n",
75 			   (cflags & ICV_IS_512) >> ICV_IS_512_SHIFT);
76 		cipher_alg = (cflags & CIPHER_ALG) >> CIPHER_ALG_SHIFT;
77 		cipher_mode = (cflags & CIPHER_MODE) >> CIPHER_MODE_SHIFT;
78 		cipher_type = (cflags & CIPHER_TYPE) >> CIPHER_TYPE_SHIFT;
79 		packet_log("    Crypto Alg:%u Mode:%u Type:%u\n",
80 			   cipher_alg, cipher_mode, cipher_type);
81 		hash_alg = (cflags & HASH_ALG) >> HASH_ALG_SHIFT;
82 		hash_mode = (cflags & HASH_MODE) >> HASH_MODE_SHIFT;
83 		hash_type = (cflags & HASH_TYPE) >> HASH_TYPE_SHIFT;
84 		packet_log("    Hash   Alg:%x Mode:%x Type:%x\n",
85 			   hash_alg, hash_mode, hash_type);
86 		packet_log("    UPDT_Offset:%u\n", cflags & UPDT_OFST);
87 
88 		ecf = be32_to_cpu(spuh->sa.ecf);
89 		packet_log("  SCTX[2] 0x%08x\n", ecf);
90 		packet_log("    WriteICV:%lu CheckICV:%lu ICV_SIZE:%u ",
91 			   (ecf & INSERT_ICV) >> INSERT_ICV_SHIFT,
92 			   (ecf & CHECK_ICV) >> CHECK_ICV_SHIFT,
93 			   (ecf & ICV_SIZE) >> ICV_SIZE_SHIFT);
94 		packet_log("BD_SUPPRESS:%lu\n",
95 			   (ecf & BD_SUPPRESS) >> BD_SUPPRESS_SHIFT);
96 		packet_log("    SCTX_IV:%lu ExplicitIV:%lu GenIV:%lu ",
97 			   (ecf & SCTX_IV) >> SCTX_IV_SHIFT,
98 			   (ecf & EXPLICIT_IV) >> EXPLICIT_IV_SHIFT,
99 			   (ecf & GEN_IV) >> GEN_IV_SHIFT);
100 		packet_log("IV_OV_OFST:%lu EXP_IV_SIZE:%u\n",
101 			   (ecf & IV_OFFSET) >> IV_OFFSET_SHIFT,
102 			   ecf & EXP_IV_SIZE);
103 
104 		ptr += sizeof(struct SCTX);
105 
106 		if (hash_alg && hash_mode) {
107 			char *name = "NONE";
108 
109 			switch (hash_alg) {
110 			case HASH_ALG_MD5:
111 				hash_key_len = 16;
112 				name = "MD5";
113 				break;
114 			case HASH_ALG_SHA1:
115 				hash_key_len = 20;
116 				name = "SHA1";
117 				break;
118 			case HASH_ALG_SHA224:
119 				hash_key_len = 28;
120 				name = "SHA224";
121 				break;
122 			case HASH_ALG_SHA256:
123 				hash_key_len = 32;
124 				name = "SHA256";
125 				break;
126 			case HASH_ALG_SHA384:
127 				hash_key_len = 48;
128 				name = "SHA384";
129 				break;
130 			case HASH_ALG_SHA512:
131 				hash_key_len = 64;
132 				name = "SHA512";
133 				break;
134 			case HASH_ALG_AES:
135 				hash_key_len = 0;
136 				name = "AES";
137 				break;
138 			case HASH_ALG_NONE:
139 				break;
140 			}
141 
142 			packet_log("    Auth Key Type:%s Length:%u Bytes\n",
143 				   name, hash_key_len);
144 			packet_dump("    KEY: ", ptr, hash_key_len);
145 			ptr += hash_key_len;
146 		} else if ((hash_alg == HASH_ALG_AES) &&
147 			   (hash_mode == HASH_MODE_XCBC)) {
148 			char *name = "NONE";
149 
150 			switch (cipher_type) {
151 			case CIPHER_TYPE_AES128:
152 				hash_key_len = 16;
153 				name = "AES128-XCBC";
154 				break;
155 			case CIPHER_TYPE_AES192:
156 				hash_key_len = 24;
157 				name = "AES192-XCBC";
158 				break;
159 			case CIPHER_TYPE_AES256:
160 				hash_key_len = 32;
161 				name = "AES256-XCBC";
162 				break;
163 			}
164 			packet_log("    Auth Key Type:%s Length:%u Bytes\n",
165 				   name, hash_key_len);
166 			packet_dump("    KEY: ", ptr, hash_key_len);
167 			ptr += hash_key_len;
168 		}
169 
170 		if (hash_alg && (hash_mode == HASH_MODE_NONE) &&
171 		    (hash_type == HASH_TYPE_UPDT)) {
172 			char *name = "NONE";
173 
174 			switch (hash_alg) {
175 			case HASH_ALG_MD5:
176 				hash_state_len = 16;
177 				name = "MD5";
178 				break;
179 			case HASH_ALG_SHA1:
180 				hash_state_len = 20;
181 				name = "SHA1";
182 				break;
183 			case HASH_ALG_SHA224:
184 				hash_state_len = 32;
185 				name = "SHA224";
186 				break;
187 			case HASH_ALG_SHA256:
188 				hash_state_len = 32;
189 				name = "SHA256";
190 				break;
191 			case HASH_ALG_SHA384:
192 				hash_state_len = 48;
193 				name = "SHA384";
194 				break;
195 			case HASH_ALG_SHA512:
196 				hash_state_len = 64;
197 				name = "SHA512";
198 				break;
199 			case HASH_ALG_AES:
200 				hash_state_len = 0;
201 				name = "AES";
202 				break;
203 			case HASH_ALG_NONE:
204 				break;
205 			}
206 
207 			packet_log("    Auth State Type:%s Length:%u Bytes\n",
208 				   name, hash_state_len);
209 			packet_dump("    State: ", ptr, hash_state_len);
210 			ptr += hash_state_len;
211 		}
212 
213 		if (cipher_alg) {
214 			char *name = "NONE";
215 
216 			switch (cipher_alg) {
217 			case CIPHER_ALG_DES:
218 				cipher_key_len = 8;
219 				name = "DES";
220 				break;
221 			case CIPHER_ALG_3DES:
222 				cipher_key_len = 24;
223 				name = "3DES";
224 				break;
225 			case CIPHER_ALG_RC4:
226 				cipher_key_len = 260;
227 				name = "ARC4";
228 				break;
229 			case CIPHER_ALG_AES:
230 				switch (cipher_type) {
231 				case CIPHER_TYPE_AES128:
232 					cipher_key_len = 16;
233 					name = "AES128";
234 					break;
235 				case CIPHER_TYPE_AES192:
236 					cipher_key_len = 24;
237 					name = "AES192";
238 					break;
239 				case CIPHER_TYPE_AES256:
240 					cipher_key_len = 32;
241 					name = "AES256";
242 					break;
243 				}
244 				break;
245 			case CIPHER_ALG_NONE:
246 				break;
247 			}
248 
249 			packet_log("    Cipher Key Type:%s Length:%u Bytes\n",
250 				   name, cipher_key_len);
251 
252 			/* XTS has two keys */
253 			if (cipher_mode == CIPHER_MODE_XTS) {
254 				packet_dump("    KEY2: ", ptr, cipher_key_len);
255 				ptr += cipher_key_len;
256 				packet_dump("    KEY1: ", ptr, cipher_key_len);
257 				ptr += cipher_key_len;
258 
259 				cipher_key_len *= 2;
260 			} else {
261 				packet_dump("    KEY: ", ptr, cipher_key_len);
262 				ptr += cipher_key_len;
263 			}
264 
265 			if (ecf & SCTX_IV) {
266 				sctx_pl_len = sctx_size * sizeof(u32) -
267 					sizeof(struct SCTX);
268 				iv_len = sctx_pl_len -
269 					(hash_key_len + hash_state_len +
270 					 cipher_key_len);
271 				packet_log("    IV Length:%u Bytes\n", iv_len);
272 				packet_dump("    IV: ", ptr, iv_len);
273 				ptr += iv_len;
274 			}
275 		}
276 	}
277 
278 	/* ========== Decode BDESC ========== */
279 	if (spuh->mh.flags & MH_BDESC_PRES) {
280 #ifdef DEBUG
281 		struct BDESC_HEADER *bdesc = (struct BDESC_HEADER *)ptr;
282 #endif
283 		packet_log("  BDESC[0] 0x%08x\n", be32_to_cpu(*((u32 *)ptr)));
284 		packet_log("    OffsetMAC:%u LengthMAC:%u\n",
285 			   be16_to_cpu(bdesc->offset_mac),
286 			   be16_to_cpu(bdesc->length_mac));
287 		ptr += sizeof(u32);
288 
289 		packet_log("  BDESC[1] 0x%08x\n", be32_to_cpu(*((u32 *)ptr)));
290 		packet_log("    OffsetCrypto:%u LengthCrypto:%u\n",
291 			   be16_to_cpu(bdesc->offset_crypto),
292 			   be16_to_cpu(bdesc->length_crypto));
293 		ptr += sizeof(u32);
294 
295 		packet_log("  BDESC[2] 0x%08x\n", be32_to_cpu(*((u32 *)ptr)));
296 		packet_log("    OffsetICV:%u OffsetIV:%u\n",
297 			   be16_to_cpu(bdesc->offset_icv),
298 			   be16_to_cpu(bdesc->offset_iv));
299 		ptr += sizeof(u32);
300 	}
301 
302 	/* ========== Decode BD ========== */
303 	if (spuh->mh.flags & MH_BD_PRES) {
304 #ifdef DEBUG
305 		struct BD_HEADER *bd = (struct BD_HEADER *)ptr;
306 #endif
307 		packet_log("  BD[0] 0x%08x\n", be32_to_cpu(*((u32 *)ptr)));
308 		packet_log("    Size:%ubytes PrevLength:%u\n",
309 			   be16_to_cpu(bd->size), be16_to_cpu(bd->prev_length));
310 		ptr += 4;
311 	}
312 
313 	/* Double check sanity */
314 	if (buf + buf_len != ptr) {
315 		packet_log(" Packet parsed incorrectly. ");
316 		packet_log("buf:%p buf_len:%u buf+buf_len:%p ptr:%p\n",
317 			   buf, buf_len, buf + buf_len, ptr);
318 	}
319 
320 	packet_log("\n");
321 }
322 
323 /**
324  * spum_ns2_ctx_max_payload() - Determine the max length of the payload for a
325  * SPU message for a given cipher and hash alg context.
326  * @cipher_alg:		The cipher algorithm
327  * @cipher_mode:	The cipher mode
328  * @blocksize:		The size of a block of data for this algo
329  *
330  * The max payload must be a multiple of the blocksize so that if a request is
331  * too large to fit in a single SPU message, the request can be broken into
332  * max_payload sized chunks. Each chunk must be a multiple of blocksize.
333  *
334  * Return: Max payload length in bytes
335  */
336 u32 spum_ns2_ctx_max_payload(enum spu_cipher_alg cipher_alg,
337 			     enum spu_cipher_mode cipher_mode,
338 			     unsigned int blocksize)
339 {
340 	u32 max_payload = SPUM_NS2_MAX_PAYLOAD;
341 	u32 excess;
342 
343 	/* In XTS on SPU-M, we'll need to insert tweak before input data */
344 	if (cipher_mode == CIPHER_MODE_XTS)
345 		max_payload -= SPU_XTS_TWEAK_SIZE;
346 
347 	excess = max_payload % blocksize;
348 
349 	return max_payload - excess;
350 }
351 
352 /**
353  * spum_nsp_ctx_max_payload() - Determine the max length of the payload for a
354  * SPU message for a given cipher and hash alg context.
355  * @cipher_alg:		The cipher algorithm
356  * @cipher_mode:	The cipher mode
357  * @blocksize:		The size of a block of data for this algo
358  *
359  * The max payload must be a multiple of the blocksize so that if a request is
360  * too large to fit in a single SPU message, the request can be broken into
361  * max_payload sized chunks. Each chunk must be a multiple of blocksize.
362  *
363  * Return: Max payload length in bytes
364  */
365 u32 spum_nsp_ctx_max_payload(enum spu_cipher_alg cipher_alg,
366 			     enum spu_cipher_mode cipher_mode,
367 			     unsigned int blocksize)
368 {
369 	u32 max_payload = SPUM_NSP_MAX_PAYLOAD;
370 	u32 excess;
371 
372 	/* In XTS on SPU-M, we'll need to insert tweak before input data */
373 	if (cipher_mode == CIPHER_MODE_XTS)
374 		max_payload -= SPU_XTS_TWEAK_SIZE;
375 
376 	excess = max_payload % blocksize;
377 
378 	return max_payload - excess;
379 }
380 
381 /** spum_payload_length() - Given a SPU-M message header, extract the payload
382  * length.
383  * @spu_hdr:	Start of SPU header
384  *
385  * Assumes just MH, EMH, BD (no SCTX, BDESC. Works for response frames.
386  *
387  * Return: payload length in bytes
388  */
389 u32 spum_payload_length(u8 *spu_hdr)
390 {
391 	struct BD_HEADER *bd;
392 	u32 pl_len;
393 
394 	/* Find BD header.  skip MH, EMH */
395 	bd = (struct BD_HEADER *)(spu_hdr + 8);
396 	pl_len = be16_to_cpu(bd->size);
397 
398 	return pl_len;
399 }
400 
401 /**
402  * spum_response_hdr_len() - Given the length of the hash key and encryption
403  * key, determine the expected length of a SPU response header.
404  * @auth_key_len:	authentication key length (bytes)
405  * @enc_key_len:	encryption key length (bytes)
406  * @is_hash:		true if response message is for a hash operation
407  *
408  * Return: length of SPU response header (bytes)
409  */
410 u16 spum_response_hdr_len(u16 auth_key_len, u16 enc_key_len, bool is_hash)
411 {
412 	if (is_hash)
413 		return SPU_HASH_RESP_HDR_LEN;
414 	else
415 		return SPU_RESP_HDR_LEN;
416 }
417 
418 /**
419  * spum_hash_pad_len() - Calculate the length of hash padding required to extend
420  * data to a full block size.
421  * @hash_alg:   hash algorithm
422  * @hash_mode:       hash mode
423  * @chunksize:  length of data, in bytes
424  * @hash_block_size:  size of a block of data for hash algorithm
425  *
426  * Reserve space for 1 byte (0x80) start of pad and the total length as u64
427  *
428  * Return:  length of hash pad in bytes
429  */
430 u16 spum_hash_pad_len(enum hash_alg hash_alg, enum hash_mode hash_mode,
431 		      u32 chunksize, u16 hash_block_size)
432 {
433 	unsigned int length_len;
434 	unsigned int used_space_last_block;
435 	int hash_pad_len;
436 
437 	/* AES-XCBC hash requires just padding to next block boundary */
438 	if ((hash_alg == HASH_ALG_AES) && (hash_mode == HASH_MODE_XCBC)) {
439 		used_space_last_block = chunksize % hash_block_size;
440 		hash_pad_len = hash_block_size - used_space_last_block;
441 		if (hash_pad_len >= hash_block_size)
442 			hash_pad_len -= hash_block_size;
443 		return hash_pad_len;
444 	}
445 
446 	used_space_last_block = chunksize % hash_block_size + 1;
447 	if ((hash_alg == HASH_ALG_SHA384) || (hash_alg == HASH_ALG_SHA512))
448 		length_len = 2 * sizeof(u64);
449 	else
450 		length_len = sizeof(u64);
451 
452 	used_space_last_block += length_len;
453 	hash_pad_len = hash_block_size - used_space_last_block;
454 	if (hash_pad_len < 0)
455 		hash_pad_len += hash_block_size;
456 
457 	hash_pad_len += 1 + length_len;
458 	return hash_pad_len;
459 }
460 
461 /**
462  * spum_gcm_ccm_pad_len() - Determine the required length of GCM or CCM padding.
463  * @cipher_mode:	Algo type
464  * @data_size:		Length of plaintext (bytes)
465  *
466  * @Return: Length of padding, in bytes
467  */
468 u32 spum_gcm_ccm_pad_len(enum spu_cipher_mode cipher_mode,
469 			 unsigned int data_size)
470 {
471 	u32 pad_len = 0;
472 	u32 m1 = SPU_GCM_CCM_ALIGN - 1;
473 
474 	if ((cipher_mode == CIPHER_MODE_GCM) ||
475 	    (cipher_mode == CIPHER_MODE_CCM))
476 		pad_len = ((data_size + m1) & ~m1) - data_size;
477 
478 	return pad_len;
479 }
480 
481 /**
482  * spum_assoc_resp_len() - Determine the size of the receive buffer required to
483  * catch associated data.
484  * @cipher_mode:	cipher mode
485  * @assoc_len:		length of associated data (bytes)
486  * @iv_len:		length of IV (bytes)
487  * @is_encrypt:		true if encrypting. false if decrypting.
488  *
489  * Return: length of associated data in response message (bytes)
490  */
491 u32 spum_assoc_resp_len(enum spu_cipher_mode cipher_mode,
492 			unsigned int assoc_len, unsigned int iv_len,
493 			bool is_encrypt)
494 {
495 	u32 buflen = 0;
496 	u32 pad;
497 
498 	if (assoc_len)
499 		buflen = assoc_len;
500 
501 	if (cipher_mode == CIPHER_MODE_GCM) {
502 		/* AAD needs to be padded in responses too */
503 		pad = spum_gcm_ccm_pad_len(cipher_mode, buflen);
504 		buflen += pad;
505 	}
506 	if (cipher_mode == CIPHER_MODE_CCM) {
507 		/*
508 		 * AAD needs to be padded in responses too
509 		 * for CCM, len + 2 needs to be 128-bit aligned.
510 		 */
511 		pad = spum_gcm_ccm_pad_len(cipher_mode, buflen + 2);
512 		buflen += pad;
513 	}
514 
515 	return buflen;
516 }
517 
518 /**
519  * spu_aead_ivlen() - Calculate the length of the AEAD IV to be included
520  * in a SPU request after the AAD and before the payload.
521  * @cipher_mode:  cipher mode
522  * @iv_ctr_len:   initialization vector length in bytes
523  *
524  * In Linux ~4.2 and later, the assoc_data sg includes the IV. So no need
525  * to include the IV as a separate field in the SPU request msg.
526  *
527  * Return: Length of AEAD IV in bytes
528  */
529 u8 spum_aead_ivlen(enum spu_cipher_mode cipher_mode, u16 iv_len)
530 {
531 	return 0;
532 }
533 
534 /**
535  * spum_hash_type() - Determine the type of hash operation.
536  * @src_sent:  The number of bytes in the current request that have already
537  *             been sent to the SPU to be hashed.
538  *
539  * We do not use HASH_TYPE_FULL for requests that fit in a single SPU message.
540  * Using FULL causes failures (such as when the string to be hashed is empty).
541  * For similar reasons, we never use HASH_TYPE_FIN. Instead, submit messages
542  * as INIT or UPDT and do the hash padding in sw.
543  */
544 enum hash_type spum_hash_type(u32 src_sent)
545 {
546 	return src_sent ? HASH_TYPE_UPDT : HASH_TYPE_INIT;
547 }
548 
549 /**
550  * spum_digest_size() - Determine the size of a hash digest to expect the SPU to
551  * return.
552  * alg_digest_size: Number of bytes in the final digest for the given algo
553  * alg:             The hash algorithm
554  * htype:           Type of hash operation (init, update, full, etc)
555  *
556  * When doing incremental hashing for an algorithm with a truncated hash
557  * (e.g., SHA224), the SPU returns the full digest so that it can be fed back as
558  * a partial result for the next chunk.
559  */
560 u32 spum_digest_size(u32 alg_digest_size, enum hash_alg alg,
561 		     enum hash_type htype)
562 {
563 	u32 digestsize = alg_digest_size;
564 
565 	/* SPU returns complete digest when doing incremental hash and truncated
566 	 * hash algo.
567 	 */
568 	if ((htype == HASH_TYPE_INIT) || (htype == HASH_TYPE_UPDT)) {
569 		if (alg == HASH_ALG_SHA224)
570 			digestsize = SHA256_DIGEST_SIZE;
571 		else if (alg == HASH_ALG_SHA384)
572 			digestsize = SHA512_DIGEST_SIZE;
573 	}
574 	return digestsize;
575 }
576 
577 /**
578  * spum_create_request() - Build a SPU request message header, up to and
579  * including the BD header. Construct the message starting at spu_hdr. Caller
580  * should allocate this buffer in DMA-able memory at least SPU_HEADER_ALLOC_LEN
581  * bytes long.
582  * @spu_hdr: Start of buffer where SPU request header is to be written
583  * @req_opts: SPU request message options
584  * @cipher_parms: Parameters related to cipher algorithm
585  * @hash_parms:   Parameters related to hash algorithm
586  * @aead_parms:   Parameters related to AEAD operation
587  * @data_size:    Length of data to be encrypted or authenticated. If AEAD, does
588  *		  not include length of AAD.
589 
590  * Return: the length of the SPU header in bytes. 0 if an error occurs.
591  */
592 u32 spum_create_request(u8 *spu_hdr,
593 			struct spu_request_opts *req_opts,
594 			struct spu_cipher_parms *cipher_parms,
595 			struct spu_hash_parms *hash_parms,
596 			struct spu_aead_parms *aead_parms,
597 			unsigned int data_size)
598 {
599 	struct SPUHEADER *spuh;
600 	struct BDESC_HEADER *bdesc;
601 	struct BD_HEADER *bd;
602 
603 	u8 *ptr;
604 	u32 protocol_bits = 0;
605 	u32 cipher_bits = 0;
606 	u32 ecf_bits = 0;
607 	u8 sctx_words = 0;
608 	unsigned int buf_len = 0;
609 
610 	/* size of the cipher payload */
611 	unsigned int cipher_len = hash_parms->prebuf_len + data_size +
612 				hash_parms->pad_len;
613 
614 	/* offset of prebuf or data from end of BD header */
615 	unsigned int cipher_offset = aead_parms->assoc_size +
616 		aead_parms->iv_len + aead_parms->aad_pad_len;
617 
618 	/* total size of the DB data (without STAT word padding) */
619 	unsigned int real_db_size = spu_real_db_size(aead_parms->assoc_size,
620 						 aead_parms->iv_len,
621 						 hash_parms->prebuf_len,
622 						 data_size,
623 						 aead_parms->aad_pad_len,
624 						 aead_parms->data_pad_len,
625 						 hash_parms->pad_len);
626 
627 	unsigned int auth_offset = 0;
628 	unsigned int offset_iv = 0;
629 
630 	/* size/offset of the auth payload */
631 	unsigned int auth_len;
632 
633 	auth_len = real_db_size;
634 
635 	if (req_opts->is_aead && req_opts->is_inbound)
636 		cipher_len -= hash_parms->digestsize;
637 
638 	if (req_opts->is_aead && req_opts->is_inbound)
639 		auth_len -= hash_parms->digestsize;
640 
641 	if ((hash_parms->alg == HASH_ALG_AES) &&
642 	    (hash_parms->mode == HASH_MODE_XCBC)) {
643 		auth_len -= hash_parms->pad_len;
644 		cipher_len -= hash_parms->pad_len;
645 	}
646 
647 	flow_log("%s()\n", __func__);
648 	flow_log("  in:%u authFirst:%u\n",
649 		 req_opts->is_inbound, req_opts->auth_first);
650 	flow_log("  %s. cipher alg:%u mode:%u type %u\n",
651 		 spu_alg_name(cipher_parms->alg, cipher_parms->mode),
652 		 cipher_parms->alg, cipher_parms->mode, cipher_parms->type);
653 	flow_log("    key: %d\n", cipher_parms->key_len);
654 	flow_dump("    key: ", cipher_parms->key_buf, cipher_parms->key_len);
655 	flow_log("    iv: %d\n", cipher_parms->iv_len);
656 	flow_dump("    iv: ", cipher_parms->iv_buf, cipher_parms->iv_len);
657 	flow_log("  auth alg:%u mode:%u type %u\n",
658 		 hash_parms->alg, hash_parms->mode, hash_parms->type);
659 	flow_log("  digestsize: %u\n", hash_parms->digestsize);
660 	flow_log("  authkey: %d\n", hash_parms->key_len);
661 	flow_dump("  authkey: ", hash_parms->key_buf, hash_parms->key_len);
662 	flow_log("  assoc_size:%u\n", aead_parms->assoc_size);
663 	flow_log("  prebuf_len:%u\n", hash_parms->prebuf_len);
664 	flow_log("  data_size:%u\n", data_size);
665 	flow_log("  hash_pad_len:%u\n", hash_parms->pad_len);
666 	flow_log("  real_db_size:%u\n", real_db_size);
667 	flow_log(" auth_offset:%u auth_len:%u cipher_offset:%u cipher_len:%u\n",
668 		 auth_offset, auth_len, cipher_offset, cipher_len);
669 	flow_log("  aead_iv: %u\n", aead_parms->iv_len);
670 
671 	/* starting out: zero the header (plus some) */
672 	ptr = spu_hdr;
673 	memset(ptr, 0, sizeof(struct SPUHEADER));
674 
675 	/* format master header word */
676 	/* Do not set the next bit even though the datasheet says to */
677 	spuh = (struct SPUHEADER *)ptr;
678 	ptr += sizeof(struct SPUHEADER);
679 	buf_len += sizeof(struct SPUHEADER);
680 
681 	spuh->mh.op_code = SPU_CRYPTO_OPERATION_GENERIC;
682 	spuh->mh.flags |= (MH_SCTX_PRES | MH_BDESC_PRES | MH_BD_PRES);
683 
684 	/* Format sctx word 0 (protocol_bits) */
685 	sctx_words = 3;		/* size in words */
686 
687 	/* Format sctx word 1 (cipher_bits) */
688 	if (req_opts->is_inbound)
689 		cipher_bits |= CIPHER_INBOUND;
690 	if (req_opts->auth_first)
691 		cipher_bits |= CIPHER_ORDER;
692 
693 	/* Set the crypto parameters in the cipher.flags */
694 	cipher_bits |= cipher_parms->alg << CIPHER_ALG_SHIFT;
695 	cipher_bits |= cipher_parms->mode << CIPHER_MODE_SHIFT;
696 	cipher_bits |= cipher_parms->type << CIPHER_TYPE_SHIFT;
697 
698 	/* Set the auth parameters in the cipher.flags */
699 	cipher_bits |= hash_parms->alg << HASH_ALG_SHIFT;
700 	cipher_bits |= hash_parms->mode << HASH_MODE_SHIFT;
701 	cipher_bits |= hash_parms->type << HASH_TYPE_SHIFT;
702 
703 	/*
704 	 * Format sctx extensions if required, and update main fields if
705 	 * required)
706 	 */
707 	if (hash_parms->alg) {
708 		/* Write the authentication key material if present */
709 		if (hash_parms->key_len) {
710 			memcpy(ptr, hash_parms->key_buf, hash_parms->key_len);
711 			ptr += hash_parms->key_len;
712 			buf_len += hash_parms->key_len;
713 			sctx_words += hash_parms->key_len / 4;
714 		}
715 
716 		if ((cipher_parms->mode == CIPHER_MODE_GCM) ||
717 		    (cipher_parms->mode == CIPHER_MODE_CCM))
718 			/* unpadded length */
719 			offset_iv = aead_parms->assoc_size;
720 
721 		/* if GCM/CCM we need to write ICV into the payload */
722 		if (!req_opts->is_inbound) {
723 			if ((cipher_parms->mode == CIPHER_MODE_GCM) ||
724 			    (cipher_parms->mode == CIPHER_MODE_CCM))
725 				ecf_bits |= 1 << INSERT_ICV_SHIFT;
726 		} else {
727 			ecf_bits |= CHECK_ICV;
728 		}
729 
730 		/* Inform the SPU of the ICV size (in words) */
731 		if (hash_parms->digestsize == 64)
732 			cipher_bits |= ICV_IS_512;
733 		else
734 			ecf_bits |=
735 			(hash_parms->digestsize / 4) << ICV_SIZE_SHIFT;
736 	}
737 
738 	if (req_opts->bd_suppress)
739 		ecf_bits |= BD_SUPPRESS;
740 
741 	/* copy the encryption keys in the SAD entry */
742 	if (cipher_parms->alg) {
743 		if (cipher_parms->key_len) {
744 			memcpy(ptr, cipher_parms->key_buf,
745 			       cipher_parms->key_len);
746 			ptr += cipher_parms->key_len;
747 			buf_len += cipher_parms->key_len;
748 			sctx_words += cipher_parms->key_len / 4;
749 		}
750 
751 		/*
752 		 * if encrypting then set IV size, use SCTX IV unless no IV
753 		 * given here
754 		 */
755 		if (cipher_parms->iv_buf && cipher_parms->iv_len) {
756 			/* Use SCTX IV */
757 			ecf_bits |= SCTX_IV;
758 
759 			/* cipher iv provided so put it in here */
760 			memcpy(ptr, cipher_parms->iv_buf, cipher_parms->iv_len);
761 
762 			ptr += cipher_parms->iv_len;
763 			buf_len += cipher_parms->iv_len;
764 			sctx_words += cipher_parms->iv_len / 4;
765 		}
766 	}
767 
768 	/*
769 	 * RFC4543 (GMAC/ESP) requires data to be sent as part of AAD
770 	 * so we need to override the BDESC parameters.
771 	 */
772 	if (req_opts->is_rfc4543) {
773 		if (req_opts->is_inbound)
774 			data_size -= hash_parms->digestsize;
775 		offset_iv = aead_parms->assoc_size + data_size;
776 		cipher_len = 0;
777 		cipher_offset = offset_iv;
778 		auth_len = cipher_offset + aead_parms->data_pad_len;
779 	}
780 
781 	/* write in the total sctx length now that we know it */
782 	protocol_bits |= sctx_words;
783 
784 	/* Endian adjust the SCTX */
785 	spuh->sa.proto_flags = cpu_to_be32(protocol_bits);
786 	spuh->sa.cipher_flags = cpu_to_be32(cipher_bits);
787 	spuh->sa.ecf = cpu_to_be32(ecf_bits);
788 
789 	/* === create the BDESC section === */
790 	bdesc = (struct BDESC_HEADER *)ptr;
791 
792 	bdesc->offset_mac = cpu_to_be16(auth_offset);
793 	bdesc->length_mac = cpu_to_be16(auth_len);
794 	bdesc->offset_crypto = cpu_to_be16(cipher_offset);
795 	bdesc->length_crypto = cpu_to_be16(cipher_len);
796 
797 	/*
798 	 * CCM in SPU-M requires that ICV not be in same 32-bit word as data or
799 	 * padding.  So account for padding as necessary.
800 	 */
801 	if (cipher_parms->mode == CIPHER_MODE_CCM)
802 		auth_len += spum_wordalign_padlen(auth_len);
803 
804 	bdesc->offset_icv = cpu_to_be16(auth_len);
805 	bdesc->offset_iv = cpu_to_be16(offset_iv);
806 
807 	ptr += sizeof(struct BDESC_HEADER);
808 	buf_len += sizeof(struct BDESC_HEADER);
809 
810 	/* === no MFM section === */
811 
812 	/* === create the BD section === */
813 
814 	/* add the BD header */
815 	bd = (struct BD_HEADER *)ptr;
816 	bd->size = cpu_to_be16(real_db_size);
817 	bd->prev_length = 0;
818 
819 	ptr += sizeof(struct BD_HEADER);
820 	buf_len += sizeof(struct BD_HEADER);
821 
822 	packet_dump("  SPU request header: ", spu_hdr, buf_len);
823 
824 	return buf_len;
825 }
826 
827 /**
828  * spum_cipher_req_init() - Build a SPU request message header, up to and
829  * including the BD header.
830  * @spu_hdr:      Start of SPU request header (MH)
831  * @cipher_parms: Parameters that describe the cipher request
832  *
833  * Construct the message starting at spu_hdr. Caller should allocate this buffer
834  * in DMA-able memory at least SPU_HEADER_ALLOC_LEN bytes long.
835  *
836  * Return: the length of the SPU header in bytes. 0 if an error occurs.
837  */
838 u16 spum_cipher_req_init(u8 *spu_hdr, struct spu_cipher_parms *cipher_parms)
839 {
840 	struct SPUHEADER *spuh;
841 	u32 protocol_bits = 0;
842 	u32 cipher_bits = 0;
843 	u32 ecf_bits = 0;
844 	u8 sctx_words = 0;
845 	u8 *ptr = spu_hdr;
846 
847 	flow_log("%s()\n", __func__);
848 	flow_log("  cipher alg:%u mode:%u type %u\n", cipher_parms->alg,
849 		 cipher_parms->mode, cipher_parms->type);
850 	flow_log("  cipher_iv_len: %u\n", cipher_parms->iv_len);
851 	flow_log("    key: %d\n", cipher_parms->key_len);
852 	flow_dump("    key: ", cipher_parms->key_buf, cipher_parms->key_len);
853 
854 	/* starting out: zero the header (plus some) */
855 	memset(spu_hdr, 0, sizeof(struct SPUHEADER));
856 	ptr += sizeof(struct SPUHEADER);
857 
858 	/* format master header word */
859 	/* Do not set the next bit even though the datasheet says to */
860 	spuh = (struct SPUHEADER *)spu_hdr;
861 
862 	spuh->mh.op_code = SPU_CRYPTO_OPERATION_GENERIC;
863 	spuh->mh.flags |= (MH_SCTX_PRES | MH_BDESC_PRES | MH_BD_PRES);
864 
865 	/* Format sctx word 0 (protocol_bits) */
866 	sctx_words = 3;		/* size in words */
867 
868 	/* copy the encryption keys in the SAD entry */
869 	if (cipher_parms->alg) {
870 		if (cipher_parms->key_len) {
871 			ptr += cipher_parms->key_len;
872 			sctx_words += cipher_parms->key_len / 4;
873 		}
874 
875 		/*
876 		 * if encrypting then set IV size, use SCTX IV unless no IV
877 		 * given here
878 		 */
879 		if (cipher_parms->iv_len) {
880 			/* Use SCTX IV */
881 			ecf_bits |= SCTX_IV;
882 			ptr += cipher_parms->iv_len;
883 			sctx_words += cipher_parms->iv_len / 4;
884 		}
885 	}
886 
887 	/* Set the crypto parameters in the cipher.flags */
888 	cipher_bits |= cipher_parms->alg << CIPHER_ALG_SHIFT;
889 	cipher_bits |= cipher_parms->mode << CIPHER_MODE_SHIFT;
890 	cipher_bits |= cipher_parms->type << CIPHER_TYPE_SHIFT;
891 
892 	/* copy the encryption keys in the SAD entry */
893 	if (cipher_parms->alg && cipher_parms->key_len)
894 		memcpy(spuh + 1, cipher_parms->key_buf, cipher_parms->key_len);
895 
896 	/* write in the total sctx length now that we know it */
897 	protocol_bits |= sctx_words;
898 
899 	/* Endian adjust the SCTX */
900 	spuh->sa.proto_flags = cpu_to_be32(protocol_bits);
901 
902 	/* Endian adjust the SCTX */
903 	spuh->sa.cipher_flags = cpu_to_be32(cipher_bits);
904 	spuh->sa.ecf = cpu_to_be32(ecf_bits);
905 
906 	packet_dump("  SPU request header: ", spu_hdr,
907 		    sizeof(struct SPUHEADER));
908 
909 	return sizeof(struct SPUHEADER) + cipher_parms->key_len +
910 		cipher_parms->iv_len + sizeof(struct BDESC_HEADER) +
911 		sizeof(struct BD_HEADER);
912 }
913 
914 /**
915  * spum_cipher_req_finish() - Finish building a SPU request message header for a
916  * block cipher request. Assumes much of the header was already filled in at
917  * setkey() time in spu_cipher_req_init().
918  * @spu_hdr:         Start of the request message header (MH field)
919  * @spu_req_hdr_len: Length in bytes of the SPU request header
920  * @isInbound:       0 encrypt, 1 decrypt
921  * @cipher_parms:    Parameters describing cipher operation to be performed
922  * @update_key:      If true, rewrite the cipher key in SCTX
923  * @data_size:       Length of the data in the BD field
924  *
925  * Assumes much of the header was already filled in at setkey() time in
926  * spum_cipher_req_init().
927  * spum_cipher_req_init() fills in the encryption key. For RC4, when submitting
928  * a request for a non-first chunk, we use the 260-byte SUPDT field from the
929  * previous response as the key. update_key is true for this case. Unused in all
930  * other cases.
931  */
932 void spum_cipher_req_finish(u8 *spu_hdr,
933 			    u16 spu_req_hdr_len,
934 			    unsigned int is_inbound,
935 			    struct spu_cipher_parms *cipher_parms,
936 			    bool update_key,
937 			    unsigned int data_size)
938 {
939 	struct SPUHEADER *spuh;
940 	struct BDESC_HEADER *bdesc;
941 	struct BD_HEADER *bd;
942 	u8 *bdesc_ptr = spu_hdr + spu_req_hdr_len -
943 	    (sizeof(struct BD_HEADER) + sizeof(struct BDESC_HEADER));
944 
945 	u32 cipher_bits;
946 
947 	flow_log("%s()\n", __func__);
948 	flow_log(" in: %u\n", is_inbound);
949 	flow_log(" cipher alg: %u, cipher_type: %u\n", cipher_parms->alg,
950 		 cipher_parms->type);
951 	if (update_key) {
952 		flow_log(" cipher key len: %u\n", cipher_parms->key_len);
953 		flow_dump("  key: ", cipher_parms->key_buf,
954 			  cipher_parms->key_len);
955 	}
956 
957 	/*
958 	 * In XTS mode, API puts "i" parameter (block tweak) in IV.  For
959 	 * SPU-M, should be in start of the BD; tx_sg_create() copies it there.
960 	 * IV in SPU msg for SPU-M should be 0, since that's the "j" parameter
961 	 * (block ctr within larger data unit) - given we can send entire disk
962 	 * block (<= 4KB) in 1 SPU msg, don't need to use this parameter.
963 	 */
964 	if (cipher_parms->mode == CIPHER_MODE_XTS)
965 		memset(cipher_parms->iv_buf, 0, cipher_parms->iv_len);
966 
967 	flow_log(" iv len: %d\n", cipher_parms->iv_len);
968 	flow_dump("    iv: ", cipher_parms->iv_buf, cipher_parms->iv_len);
969 	flow_log(" data_size: %u\n", data_size);
970 
971 	/* format master header word */
972 	/* Do not set the next bit even though the datasheet says to */
973 	spuh = (struct SPUHEADER *)spu_hdr;
974 
975 	/* cipher_bits was initialized at setkey time */
976 	cipher_bits = be32_to_cpu(spuh->sa.cipher_flags);
977 
978 	/* Format sctx word 1 (cipher_bits) */
979 	if (is_inbound)
980 		cipher_bits |= CIPHER_INBOUND;
981 	else
982 		cipher_bits &= ~CIPHER_INBOUND;
983 
984 	/* update encryption key for RC4 on non-first chunk */
985 	if (update_key) {
986 		spuh->sa.cipher_flags |=
987 			cipher_parms->type << CIPHER_TYPE_SHIFT;
988 		memcpy(spuh + 1, cipher_parms->key_buf, cipher_parms->key_len);
989 	}
990 
991 	if (cipher_parms->alg && cipher_parms->iv_buf && cipher_parms->iv_len)
992 		/* cipher iv provided so put it in here */
993 		memcpy(bdesc_ptr - cipher_parms->iv_len, cipher_parms->iv_buf,
994 		       cipher_parms->iv_len);
995 
996 	spuh->sa.cipher_flags = cpu_to_be32(cipher_bits);
997 
998 	/* === create the BDESC section === */
999 	bdesc = (struct BDESC_HEADER *)bdesc_ptr;
1000 	bdesc->offset_mac = 0;
1001 	bdesc->length_mac = 0;
1002 	bdesc->offset_crypto = 0;
1003 
1004 	/* XTS mode, data_size needs to include tweak parameter */
1005 	if (cipher_parms->mode == CIPHER_MODE_XTS)
1006 		bdesc->length_crypto = cpu_to_be16(data_size +
1007 						  SPU_XTS_TWEAK_SIZE);
1008 	else
1009 		bdesc->length_crypto = cpu_to_be16(data_size);
1010 
1011 	bdesc->offset_icv = 0;
1012 	bdesc->offset_iv = 0;
1013 
1014 	/* === no MFM section === */
1015 
1016 	/* === create the BD section === */
1017 	/* add the BD header */
1018 	bd = (struct BD_HEADER *)(bdesc_ptr + sizeof(struct BDESC_HEADER));
1019 	bd->size = cpu_to_be16(data_size);
1020 
1021 	/* XTS mode, data_size needs to include tweak parameter */
1022 	if (cipher_parms->mode == CIPHER_MODE_XTS)
1023 		bd->size = cpu_to_be16(data_size + SPU_XTS_TWEAK_SIZE);
1024 	else
1025 		bd->size = cpu_to_be16(data_size);
1026 
1027 	bd->prev_length = 0;
1028 
1029 	packet_dump("  SPU request header: ", spu_hdr, spu_req_hdr_len);
1030 }
1031 
1032 /**
1033  * spum_request_pad() - Create pad bytes at the end of the data.
1034  * @pad_start:		Start of buffer where pad bytes are to be written
1035  * @gcm_ccm_padding:	length of GCM/CCM padding, in bytes
1036  * @hash_pad_len:	Number of bytes of padding extend data to full block
1037  * @auth_alg:		authentication algorithm
1038  * @auth_mode:		authentication mode
1039  * @total_sent:		length inserted at end of hash pad
1040  * @status_padding:	Number of bytes of padding to align STATUS word
1041  *
1042  * There may be three forms of pad:
1043  *  1. GCM/CCM pad - for GCM/CCM mode ciphers, pad to 16-byte alignment
1044  *  2. hash pad - pad to a block length, with 0x80 data terminator and
1045  *                size at the end
1046  *  3. STAT pad - to ensure the STAT field is 4-byte aligned
1047  */
1048 void spum_request_pad(u8 *pad_start,
1049 		      u32 gcm_ccm_padding,
1050 		      u32 hash_pad_len,
1051 		      enum hash_alg auth_alg,
1052 		      enum hash_mode auth_mode,
1053 		      unsigned int total_sent, u32 status_padding)
1054 {
1055 	u8 *ptr = pad_start;
1056 
1057 	/* fix data alignent for GCM/CCM */
1058 	if (gcm_ccm_padding > 0) {
1059 		flow_log("  GCM: padding to 16 byte alignment: %u bytes\n",
1060 			 gcm_ccm_padding);
1061 		memset(ptr, 0, gcm_ccm_padding);
1062 		ptr += gcm_ccm_padding;
1063 	}
1064 
1065 	if (hash_pad_len > 0) {
1066 		/* clear the padding section */
1067 		memset(ptr, 0, hash_pad_len);
1068 
1069 		if ((auth_alg == HASH_ALG_AES) &&
1070 		    (auth_mode == HASH_MODE_XCBC)) {
1071 			/* AES/XCBC just requires padding to be 0s */
1072 			ptr += hash_pad_len;
1073 		} else {
1074 			/* terminate the data */
1075 			*ptr = 0x80;
1076 			ptr += (hash_pad_len - sizeof(u64));
1077 
1078 			/* add the size at the end as required per alg */
1079 			if (auth_alg == HASH_ALG_MD5)
1080 				*(u64 *)ptr = cpu_to_le64((u64)total_sent * 8);
1081 			else		/* SHA1, SHA2-224, SHA2-256 */
1082 				*(u64 *)ptr = cpu_to_be64((u64)total_sent * 8);
1083 			ptr += sizeof(u64);
1084 		}
1085 	}
1086 
1087 	/* pad to a 4byte alignment for STAT */
1088 	if (status_padding > 0) {
1089 		flow_log("  STAT: padding to 4 byte alignment: %u bytes\n",
1090 			 status_padding);
1091 
1092 		memset(ptr, 0, status_padding);
1093 		ptr += status_padding;
1094 	}
1095 }
1096 
1097 /**
1098  * spum_xts_tweak_in_payload() - Indicate that SPUM DOES place the XTS tweak
1099  * field in the packet payload (rather than using IV)
1100  *
1101  * Return: 1
1102  */
1103 u8 spum_xts_tweak_in_payload(void)
1104 {
1105 	return 1;
1106 }
1107 
1108 /**
1109  * spum_tx_status_len() - Return the length of the STATUS field in a SPU
1110  * response message.
1111  *
1112  * Return: Length of STATUS field in bytes.
1113  */
1114 u8 spum_tx_status_len(void)
1115 {
1116 	return SPU_TX_STATUS_LEN;
1117 }
1118 
1119 /**
1120  * spum_rx_status_len() - Return the length of the STATUS field in a SPU
1121  * response message.
1122  *
1123  * Return: Length of STATUS field in bytes.
1124  */
1125 u8 spum_rx_status_len(void)
1126 {
1127 	return SPU_RX_STATUS_LEN;
1128 }
1129 
1130 /**
1131  * spum_status_process() - Process the status from a SPU response message.
1132  * @statp:  start of STATUS word
1133  * Return:
1134  *   0 - if status is good and response should be processed
1135  *   !0 - status indicates an error and response is invalid
1136  */
1137 int spum_status_process(u8 *statp)
1138 {
1139 	u32 status;
1140 
1141 	status = __be32_to_cpu(*(__be32 *)statp);
1142 	flow_log("SPU response STATUS %#08x\n", status);
1143 	if (status & SPU_STATUS_ERROR_FLAG) {
1144 		pr_err("%s() Warning: Error result from SPU: %#08x\n",
1145 		       __func__, status);
1146 		if (status & SPU_STATUS_INVALID_ICV)
1147 			return SPU_INVALID_ICV;
1148 		return -EBADMSG;
1149 	}
1150 	return 0;
1151 }
1152 
1153 /**
1154  * spum_ccm_update_iv() - Update the IV as per the requirements for CCM mode.
1155  *
1156  * @digestsize:		Digest size of this request
1157  * @cipher_parms:	(pointer to) cipher parmaeters, includes IV buf & IV len
1158  * @assoclen:		Length of AAD data
1159  * @chunksize:		length of input data to be sent in this req
1160  * @is_encrypt:		true if this is an output/encrypt operation
1161  * @is_esp:		true if this is an ESP / RFC4309 operation
1162  *
1163  */
1164 void spum_ccm_update_iv(unsigned int digestsize,
1165 			struct spu_cipher_parms *cipher_parms,
1166 			unsigned int assoclen,
1167 			unsigned int chunksize,
1168 			bool is_encrypt,
1169 			bool is_esp)
1170 {
1171 	u8 L;		/* L from CCM algorithm, length of plaintext data */
1172 	u8 mprime;	/* M' from CCM algo, (M - 2) / 2, where M=authsize */
1173 	u8 adata;
1174 
1175 	if (cipher_parms->iv_len != CCM_AES_IV_SIZE) {
1176 		pr_err("%s(): Invalid IV len %d for CCM mode, should be %d\n",
1177 		       __func__, cipher_parms->iv_len, CCM_AES_IV_SIZE);
1178 		return;
1179 	}
1180 
1181 	/*
1182 	 * IV needs to be formatted as follows:
1183 	 *
1184 	 * |          Byte 0               | Bytes 1 - N | Bytes (N+1) - 15 |
1185 	 * | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | Bits 7 - 0  |    Bits 7 - 0    |
1186 	 * | 0 |Ad?|(M - 2) / 2|   L - 1   |    Nonce    | Plaintext Length |
1187 	 *
1188 	 * Ad? = 1 if AAD present, 0 if not present
1189 	 * M = size of auth field, 8, 12, or 16 bytes (SPU-M) -or-
1190 	 *                         4, 6, 8, 10, 12, 14, 16 bytes (SPU2)
1191 	 * L = Size of Plaintext Length field; Nonce size = 15 - L
1192 	 *
1193 	 * It appears that the crypto API already expects the L-1 portion
1194 	 * to be set in the first byte of the IV, which implicitly determines
1195 	 * the nonce size, and also fills in the nonce.  But the other bits
1196 	 * in byte 0 as well as the plaintext length need to be filled in.
1197 	 *
1198 	 * In rfc4309/esp mode, L is not already in the supplied IV and
1199 	 * we need to fill it in, as well as move the IV data to be after
1200 	 * the salt
1201 	 */
1202 	if (is_esp) {
1203 		L = CCM_ESP_L_VALUE;	/* RFC4309 has fixed L */
1204 	} else {
1205 		/* L' = plaintext length - 1 so Plaintext length is L' + 1 */
1206 		L = ((cipher_parms->iv_buf[0] & CCM_B0_L_PRIME) >>
1207 		      CCM_B0_L_PRIME_SHIFT) + 1;
1208 	}
1209 
1210 	mprime = (digestsize - 2) >> 1;  /* M' = (M - 2) / 2 */
1211 	adata = (assoclen > 0);  /* adata = 1 if any associated data */
1212 
1213 	cipher_parms->iv_buf[0] = (adata << CCM_B0_ADATA_SHIFT) |
1214 				  (mprime << CCM_B0_M_PRIME_SHIFT) |
1215 				  ((L - 1) << CCM_B0_L_PRIME_SHIFT);
1216 
1217 	/* Nonce is already filled in by crypto API, and is 15 - L bytes */
1218 
1219 	/* Don't include digest in plaintext size when decrypting */
1220 	if (!is_encrypt)
1221 		chunksize -= digestsize;
1222 
1223 	/* Fill in length of plaintext, formatted to be L bytes long */
1224 	format_value_ccm(chunksize, &cipher_parms->iv_buf[15 - L + 1], L);
1225 }
1226 
1227 /**
1228  * spum_wordalign_padlen() - Given the length of a data field, determine the
1229  * padding required to align the data following this field on a 4-byte boundary.
1230  * @data_size: length of data field in bytes
1231  *
1232  * Return: length of status field padding, in bytes
1233  */
1234 u32 spum_wordalign_padlen(u32 data_size)
1235 {
1236 	return ((data_size + 3) & ~3) - data_size;
1237 }
1238