xref: /openbmc/linux/drivers/crypto/bcm/spu.c (revision 6abeae2a)
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_AES:
226 				switch (cipher_type) {
227 				case CIPHER_TYPE_AES128:
228 					cipher_key_len = 16;
229 					name = "AES128";
230 					break;
231 				case CIPHER_TYPE_AES192:
232 					cipher_key_len = 24;
233 					name = "AES192";
234 					break;
235 				case CIPHER_TYPE_AES256:
236 					cipher_key_len = 32;
237 					name = "AES256";
238 					break;
239 				}
240 				break;
241 			case CIPHER_ALG_NONE:
242 				break;
243 			}
244 
245 			packet_log("    Cipher Key Type:%s Length:%u Bytes\n",
246 				   name, cipher_key_len);
247 
248 			/* XTS has two keys */
249 			if (cipher_mode == CIPHER_MODE_XTS) {
250 				packet_dump("    KEY2: ", ptr, cipher_key_len);
251 				ptr += cipher_key_len;
252 				packet_dump("    KEY1: ", ptr, cipher_key_len);
253 				ptr += cipher_key_len;
254 
255 				cipher_key_len *= 2;
256 			} else {
257 				packet_dump("    KEY: ", ptr, cipher_key_len);
258 				ptr += cipher_key_len;
259 			}
260 
261 			if (ecf & SCTX_IV) {
262 				sctx_pl_len = sctx_size * sizeof(u32) -
263 					sizeof(struct SCTX);
264 				iv_len = sctx_pl_len -
265 					(hash_key_len + hash_state_len +
266 					 cipher_key_len);
267 				packet_log("    IV Length:%u Bytes\n", iv_len);
268 				packet_dump("    IV: ", ptr, iv_len);
269 				ptr += iv_len;
270 			}
271 		}
272 	}
273 
274 	/* ========== Decode BDESC ========== */
275 	if (spuh->mh.flags & MH_BDESC_PRES) {
276 #ifdef DEBUG
277 		struct BDESC_HEADER *bdesc = (struct BDESC_HEADER *)ptr;
278 #endif
279 		packet_log("  BDESC[0] 0x%08x\n", be32_to_cpu(*((u32 *)ptr)));
280 		packet_log("    OffsetMAC:%u LengthMAC:%u\n",
281 			   be16_to_cpu(bdesc->offset_mac),
282 			   be16_to_cpu(bdesc->length_mac));
283 		ptr += sizeof(u32);
284 
285 		packet_log("  BDESC[1] 0x%08x\n", be32_to_cpu(*((u32 *)ptr)));
286 		packet_log("    OffsetCrypto:%u LengthCrypto:%u\n",
287 			   be16_to_cpu(bdesc->offset_crypto),
288 			   be16_to_cpu(bdesc->length_crypto));
289 		ptr += sizeof(u32);
290 
291 		packet_log("  BDESC[2] 0x%08x\n", be32_to_cpu(*((u32 *)ptr)));
292 		packet_log("    OffsetICV:%u OffsetIV:%u\n",
293 			   be16_to_cpu(bdesc->offset_icv),
294 			   be16_to_cpu(bdesc->offset_iv));
295 		ptr += sizeof(u32);
296 	}
297 
298 	/* ========== Decode BD ========== */
299 	if (spuh->mh.flags & MH_BD_PRES) {
300 #ifdef DEBUG
301 		struct BD_HEADER *bd = (struct BD_HEADER *)ptr;
302 #endif
303 		packet_log("  BD[0] 0x%08x\n", be32_to_cpu(*((u32 *)ptr)));
304 		packet_log("    Size:%ubytes PrevLength:%u\n",
305 			   be16_to_cpu(bd->size), be16_to_cpu(bd->prev_length));
306 		ptr += 4;
307 	}
308 
309 	/* Double check sanity */
310 	if (buf + buf_len != ptr) {
311 		packet_log(" Packet parsed incorrectly. ");
312 		packet_log("buf:%p buf_len:%u buf+buf_len:%p ptr:%p\n",
313 			   buf, buf_len, buf + buf_len, ptr);
314 	}
315 
316 	packet_log("\n");
317 }
318 
319 /**
320  * spum_ns2_ctx_max_payload() - Determine the max length of the payload for a
321  * SPU message for a given cipher and hash alg context.
322  * @cipher_alg:		The cipher algorithm
323  * @cipher_mode:	The cipher mode
324  * @blocksize:		The size of a block of data for this algo
325  *
326  * The max payload must be a multiple of the blocksize so that if a request is
327  * too large to fit in a single SPU message, the request can be broken into
328  * max_payload sized chunks. Each chunk must be a multiple of blocksize.
329  *
330  * Return: Max payload length in bytes
331  */
332 u32 spum_ns2_ctx_max_payload(enum spu_cipher_alg cipher_alg,
333 			     enum spu_cipher_mode cipher_mode,
334 			     unsigned int blocksize)
335 {
336 	u32 max_payload = SPUM_NS2_MAX_PAYLOAD;
337 	u32 excess;
338 
339 	/* In XTS on SPU-M, we'll need to insert tweak before input data */
340 	if (cipher_mode == CIPHER_MODE_XTS)
341 		max_payload -= SPU_XTS_TWEAK_SIZE;
342 
343 	excess = max_payload % blocksize;
344 
345 	return max_payload - excess;
346 }
347 
348 /**
349  * spum_nsp_ctx_max_payload() - Determine the max length of the payload for a
350  * SPU message for a given cipher and hash alg context.
351  * @cipher_alg:		The cipher algorithm
352  * @cipher_mode:	The cipher mode
353  * @blocksize:		The size of a block of data for this algo
354  *
355  * The max payload must be a multiple of the blocksize so that if a request is
356  * too large to fit in a single SPU message, the request can be broken into
357  * max_payload sized chunks. Each chunk must be a multiple of blocksize.
358  *
359  * Return: Max payload length in bytes
360  */
361 u32 spum_nsp_ctx_max_payload(enum spu_cipher_alg cipher_alg,
362 			     enum spu_cipher_mode cipher_mode,
363 			     unsigned int blocksize)
364 {
365 	u32 max_payload = SPUM_NSP_MAX_PAYLOAD;
366 	u32 excess;
367 
368 	/* In XTS on SPU-M, we'll need to insert tweak before input data */
369 	if (cipher_mode == CIPHER_MODE_XTS)
370 		max_payload -= SPU_XTS_TWEAK_SIZE;
371 
372 	excess = max_payload % blocksize;
373 
374 	return max_payload - excess;
375 }
376 
377 /** spum_payload_length() - Given a SPU-M message header, extract the payload
378  * length.
379  * @spu_hdr:	Start of SPU header
380  *
381  * Assumes just MH, EMH, BD (no SCTX, BDESC. Works for response frames.
382  *
383  * Return: payload length in bytes
384  */
385 u32 spum_payload_length(u8 *spu_hdr)
386 {
387 	struct BD_HEADER *bd;
388 	u32 pl_len;
389 
390 	/* Find BD header.  skip MH, EMH */
391 	bd = (struct BD_HEADER *)(spu_hdr + 8);
392 	pl_len = be16_to_cpu(bd->size);
393 
394 	return pl_len;
395 }
396 
397 /**
398  * spum_response_hdr_len() - Given the length of the hash key and encryption
399  * key, determine the expected length of a SPU response header.
400  * @auth_key_len:	authentication key length (bytes)
401  * @enc_key_len:	encryption key length (bytes)
402  * @is_hash:		true if response message is for a hash operation
403  *
404  * Return: length of SPU response header (bytes)
405  */
406 u16 spum_response_hdr_len(u16 auth_key_len, u16 enc_key_len, bool is_hash)
407 {
408 	if (is_hash)
409 		return SPU_HASH_RESP_HDR_LEN;
410 	else
411 		return SPU_RESP_HDR_LEN;
412 }
413 
414 /**
415  * spum_hash_pad_len() - Calculate the length of hash padding required to extend
416  * data to a full block size.
417  * @hash_alg:   hash algorithm
418  * @hash_mode:       hash mode
419  * @chunksize:  length of data, in bytes
420  * @hash_block_size:  size of a block of data for hash algorithm
421  *
422  * Reserve space for 1 byte (0x80) start of pad and the total length as u64
423  *
424  * Return:  length of hash pad in bytes
425  */
426 u16 spum_hash_pad_len(enum hash_alg hash_alg, enum hash_mode hash_mode,
427 		      u32 chunksize, u16 hash_block_size)
428 {
429 	unsigned int length_len;
430 	unsigned int used_space_last_block;
431 	int hash_pad_len;
432 
433 	/* AES-XCBC hash requires just padding to next block boundary */
434 	if ((hash_alg == HASH_ALG_AES) && (hash_mode == HASH_MODE_XCBC)) {
435 		used_space_last_block = chunksize % hash_block_size;
436 		hash_pad_len = hash_block_size - used_space_last_block;
437 		if (hash_pad_len >= hash_block_size)
438 			hash_pad_len -= hash_block_size;
439 		return hash_pad_len;
440 	}
441 
442 	used_space_last_block = chunksize % hash_block_size + 1;
443 	if ((hash_alg == HASH_ALG_SHA384) || (hash_alg == HASH_ALG_SHA512))
444 		length_len = 2 * sizeof(u64);
445 	else
446 		length_len = sizeof(u64);
447 
448 	used_space_last_block += length_len;
449 	hash_pad_len = hash_block_size - used_space_last_block;
450 	if (hash_pad_len < 0)
451 		hash_pad_len += hash_block_size;
452 
453 	hash_pad_len += 1 + length_len;
454 	return hash_pad_len;
455 }
456 
457 /**
458  * spum_gcm_ccm_pad_len() - Determine the required length of GCM or CCM padding.
459  * @cipher_mode:	Algo type
460  * @data_size:		Length of plaintext (bytes)
461  *
462  * @Return: Length of padding, in bytes
463  */
464 u32 spum_gcm_ccm_pad_len(enum spu_cipher_mode cipher_mode,
465 			 unsigned int data_size)
466 {
467 	u32 pad_len = 0;
468 	u32 m1 = SPU_GCM_CCM_ALIGN - 1;
469 
470 	if ((cipher_mode == CIPHER_MODE_GCM) ||
471 	    (cipher_mode == CIPHER_MODE_CCM))
472 		pad_len = ((data_size + m1) & ~m1) - data_size;
473 
474 	return pad_len;
475 }
476 
477 /**
478  * spum_assoc_resp_len() - Determine the size of the receive buffer required to
479  * catch associated data.
480  * @cipher_mode:	cipher mode
481  * @assoc_len:		length of associated data (bytes)
482  * @iv_len:		length of IV (bytes)
483  * @is_encrypt:		true if encrypting. false if decrypting.
484  *
485  * Return: length of associated data in response message (bytes)
486  */
487 u32 spum_assoc_resp_len(enum spu_cipher_mode cipher_mode,
488 			unsigned int assoc_len, unsigned int iv_len,
489 			bool is_encrypt)
490 {
491 	u32 buflen = 0;
492 	u32 pad;
493 
494 	if (assoc_len)
495 		buflen = assoc_len;
496 
497 	if (cipher_mode == CIPHER_MODE_GCM) {
498 		/* AAD needs to be padded in responses too */
499 		pad = spum_gcm_ccm_pad_len(cipher_mode, buflen);
500 		buflen += pad;
501 	}
502 	if (cipher_mode == CIPHER_MODE_CCM) {
503 		/*
504 		 * AAD needs to be padded in responses too
505 		 * for CCM, len + 2 needs to be 128-bit aligned.
506 		 */
507 		pad = spum_gcm_ccm_pad_len(cipher_mode, buflen + 2);
508 		buflen += pad;
509 	}
510 
511 	return buflen;
512 }
513 
514 /**
515  * spu_aead_ivlen() - Calculate the length of the AEAD IV to be included
516  * in a SPU request after the AAD and before the payload.
517  * @cipher_mode:  cipher mode
518  * @iv_ctr_len:   initialization vector length in bytes
519  *
520  * In Linux ~4.2 and later, the assoc_data sg includes the IV. So no need
521  * to include the IV as a separate field in the SPU request msg.
522  *
523  * Return: Length of AEAD IV in bytes
524  */
525 u8 spum_aead_ivlen(enum spu_cipher_mode cipher_mode, u16 iv_len)
526 {
527 	return 0;
528 }
529 
530 /**
531  * spum_hash_type() - Determine the type of hash operation.
532  * @src_sent:  The number of bytes in the current request that have already
533  *             been sent to the SPU to be hashed.
534  *
535  * We do not use HASH_TYPE_FULL for requests that fit in a single SPU message.
536  * Using FULL causes failures (such as when the string to be hashed is empty).
537  * For similar reasons, we never use HASH_TYPE_FIN. Instead, submit messages
538  * as INIT or UPDT and do the hash padding in sw.
539  */
540 enum hash_type spum_hash_type(u32 src_sent)
541 {
542 	return src_sent ? HASH_TYPE_UPDT : HASH_TYPE_INIT;
543 }
544 
545 /**
546  * spum_digest_size() - Determine the size of a hash digest to expect the SPU to
547  * return.
548  * alg_digest_size: Number of bytes in the final digest for the given algo
549  * alg:             The hash algorithm
550  * htype:           Type of hash operation (init, update, full, etc)
551  *
552  * When doing incremental hashing for an algorithm with a truncated hash
553  * (e.g., SHA224), the SPU returns the full digest so that it can be fed back as
554  * a partial result for the next chunk.
555  */
556 u32 spum_digest_size(u32 alg_digest_size, enum hash_alg alg,
557 		     enum hash_type htype)
558 {
559 	u32 digestsize = alg_digest_size;
560 
561 	/* SPU returns complete digest when doing incremental hash and truncated
562 	 * hash algo.
563 	 */
564 	if ((htype == HASH_TYPE_INIT) || (htype == HASH_TYPE_UPDT)) {
565 		if (alg == HASH_ALG_SHA224)
566 			digestsize = SHA256_DIGEST_SIZE;
567 		else if (alg == HASH_ALG_SHA384)
568 			digestsize = SHA512_DIGEST_SIZE;
569 	}
570 	return digestsize;
571 }
572 
573 /**
574  * spum_create_request() - Build a SPU request message header, up to and
575  * including the BD header. Construct the message starting at spu_hdr. Caller
576  * should allocate this buffer in DMA-able memory at least SPU_HEADER_ALLOC_LEN
577  * bytes long.
578  * @spu_hdr: Start of buffer where SPU request header is to be written
579  * @req_opts: SPU request message options
580  * @cipher_parms: Parameters related to cipher algorithm
581  * @hash_parms:   Parameters related to hash algorithm
582  * @aead_parms:   Parameters related to AEAD operation
583  * @data_size:    Length of data to be encrypted or authenticated. If AEAD, does
584  *		  not include length of AAD.
585 
586  * Return: the length of the SPU header in bytes. 0 if an error occurs.
587  */
588 u32 spum_create_request(u8 *spu_hdr,
589 			struct spu_request_opts *req_opts,
590 			struct spu_cipher_parms *cipher_parms,
591 			struct spu_hash_parms *hash_parms,
592 			struct spu_aead_parms *aead_parms,
593 			unsigned int data_size)
594 {
595 	struct SPUHEADER *spuh;
596 	struct BDESC_HEADER *bdesc;
597 	struct BD_HEADER *bd;
598 
599 	u8 *ptr;
600 	u32 protocol_bits = 0;
601 	u32 cipher_bits = 0;
602 	u32 ecf_bits = 0;
603 	u8 sctx_words = 0;
604 	unsigned int buf_len = 0;
605 
606 	/* size of the cipher payload */
607 	unsigned int cipher_len = hash_parms->prebuf_len + data_size +
608 				hash_parms->pad_len;
609 
610 	/* offset of prebuf or data from end of BD header */
611 	unsigned int cipher_offset = aead_parms->assoc_size +
612 		aead_parms->iv_len + aead_parms->aad_pad_len;
613 
614 	/* total size of the DB data (without STAT word padding) */
615 	unsigned int real_db_size = spu_real_db_size(aead_parms->assoc_size,
616 						 aead_parms->iv_len,
617 						 hash_parms->prebuf_len,
618 						 data_size,
619 						 aead_parms->aad_pad_len,
620 						 aead_parms->data_pad_len,
621 						 hash_parms->pad_len);
622 
623 	unsigned int auth_offset = 0;
624 	unsigned int offset_iv = 0;
625 
626 	/* size/offset of the auth payload */
627 	unsigned int auth_len;
628 
629 	auth_len = real_db_size;
630 
631 	if (req_opts->is_aead && req_opts->is_inbound)
632 		cipher_len -= hash_parms->digestsize;
633 
634 	if (req_opts->is_aead && req_opts->is_inbound)
635 		auth_len -= hash_parms->digestsize;
636 
637 	if ((hash_parms->alg == HASH_ALG_AES) &&
638 	    (hash_parms->mode == HASH_MODE_XCBC)) {
639 		auth_len -= hash_parms->pad_len;
640 		cipher_len -= hash_parms->pad_len;
641 	}
642 
643 	flow_log("%s()\n", __func__);
644 	flow_log("  in:%u authFirst:%u\n",
645 		 req_opts->is_inbound, req_opts->auth_first);
646 	flow_log("  %s. cipher alg:%u mode:%u type %u\n",
647 		 spu_alg_name(cipher_parms->alg, cipher_parms->mode),
648 		 cipher_parms->alg, cipher_parms->mode, cipher_parms->type);
649 	flow_log("    key: %d\n", cipher_parms->key_len);
650 	flow_dump("    key: ", cipher_parms->key_buf, cipher_parms->key_len);
651 	flow_log("    iv: %d\n", cipher_parms->iv_len);
652 	flow_dump("    iv: ", cipher_parms->iv_buf, cipher_parms->iv_len);
653 	flow_log("  auth alg:%u mode:%u type %u\n",
654 		 hash_parms->alg, hash_parms->mode, hash_parms->type);
655 	flow_log("  digestsize: %u\n", hash_parms->digestsize);
656 	flow_log("  authkey: %d\n", hash_parms->key_len);
657 	flow_dump("  authkey: ", hash_parms->key_buf, hash_parms->key_len);
658 	flow_log("  assoc_size:%u\n", aead_parms->assoc_size);
659 	flow_log("  prebuf_len:%u\n", hash_parms->prebuf_len);
660 	flow_log("  data_size:%u\n", data_size);
661 	flow_log("  hash_pad_len:%u\n", hash_parms->pad_len);
662 	flow_log("  real_db_size:%u\n", real_db_size);
663 	flow_log(" auth_offset:%u auth_len:%u cipher_offset:%u cipher_len:%u\n",
664 		 auth_offset, auth_len, cipher_offset, cipher_len);
665 	flow_log("  aead_iv: %u\n", aead_parms->iv_len);
666 
667 	/* starting out: zero the header (plus some) */
668 	ptr = spu_hdr;
669 	memset(ptr, 0, sizeof(struct SPUHEADER));
670 
671 	/* format master header word */
672 	/* Do not set the next bit even though the datasheet says to */
673 	spuh = (struct SPUHEADER *)ptr;
674 	ptr += sizeof(struct SPUHEADER);
675 	buf_len += sizeof(struct SPUHEADER);
676 
677 	spuh->mh.op_code = SPU_CRYPTO_OPERATION_GENERIC;
678 	spuh->mh.flags |= (MH_SCTX_PRES | MH_BDESC_PRES | MH_BD_PRES);
679 
680 	/* Format sctx word 0 (protocol_bits) */
681 	sctx_words = 3;		/* size in words */
682 
683 	/* Format sctx word 1 (cipher_bits) */
684 	if (req_opts->is_inbound)
685 		cipher_bits |= CIPHER_INBOUND;
686 	if (req_opts->auth_first)
687 		cipher_bits |= CIPHER_ORDER;
688 
689 	/* Set the crypto parameters in the cipher.flags */
690 	cipher_bits |= cipher_parms->alg << CIPHER_ALG_SHIFT;
691 	cipher_bits |= cipher_parms->mode << CIPHER_MODE_SHIFT;
692 	cipher_bits |= cipher_parms->type << CIPHER_TYPE_SHIFT;
693 
694 	/* Set the auth parameters in the cipher.flags */
695 	cipher_bits |= hash_parms->alg << HASH_ALG_SHIFT;
696 	cipher_bits |= hash_parms->mode << HASH_MODE_SHIFT;
697 	cipher_bits |= hash_parms->type << HASH_TYPE_SHIFT;
698 
699 	/*
700 	 * Format sctx extensions if required, and update main fields if
701 	 * required)
702 	 */
703 	if (hash_parms->alg) {
704 		/* Write the authentication key material if present */
705 		if (hash_parms->key_len) {
706 			memcpy(ptr, hash_parms->key_buf, hash_parms->key_len);
707 			ptr += hash_parms->key_len;
708 			buf_len += hash_parms->key_len;
709 			sctx_words += hash_parms->key_len / 4;
710 		}
711 
712 		if ((cipher_parms->mode == CIPHER_MODE_GCM) ||
713 		    (cipher_parms->mode == CIPHER_MODE_CCM))
714 			/* unpadded length */
715 			offset_iv = aead_parms->assoc_size;
716 
717 		/* if GCM/CCM we need to write ICV into the payload */
718 		if (!req_opts->is_inbound) {
719 			if ((cipher_parms->mode == CIPHER_MODE_GCM) ||
720 			    (cipher_parms->mode == CIPHER_MODE_CCM))
721 				ecf_bits |= 1 << INSERT_ICV_SHIFT;
722 		} else {
723 			ecf_bits |= CHECK_ICV;
724 		}
725 
726 		/* Inform the SPU of the ICV size (in words) */
727 		if (hash_parms->digestsize == 64)
728 			cipher_bits |= ICV_IS_512;
729 		else
730 			ecf_bits |=
731 			(hash_parms->digestsize / 4) << ICV_SIZE_SHIFT;
732 	}
733 
734 	if (req_opts->bd_suppress)
735 		ecf_bits |= BD_SUPPRESS;
736 
737 	/* copy the encryption keys in the SAD entry */
738 	if (cipher_parms->alg) {
739 		if (cipher_parms->key_len) {
740 			memcpy(ptr, cipher_parms->key_buf,
741 			       cipher_parms->key_len);
742 			ptr += cipher_parms->key_len;
743 			buf_len += cipher_parms->key_len;
744 			sctx_words += cipher_parms->key_len / 4;
745 		}
746 
747 		/*
748 		 * if encrypting then set IV size, use SCTX IV unless no IV
749 		 * given here
750 		 */
751 		if (cipher_parms->iv_buf && cipher_parms->iv_len) {
752 			/* Use SCTX IV */
753 			ecf_bits |= SCTX_IV;
754 
755 			/* cipher iv provided so put it in here */
756 			memcpy(ptr, cipher_parms->iv_buf, cipher_parms->iv_len);
757 
758 			ptr += cipher_parms->iv_len;
759 			buf_len += cipher_parms->iv_len;
760 			sctx_words += cipher_parms->iv_len / 4;
761 		}
762 	}
763 
764 	/*
765 	 * RFC4543 (GMAC/ESP) requires data to be sent as part of AAD
766 	 * so we need to override the BDESC parameters.
767 	 */
768 	if (req_opts->is_rfc4543) {
769 		if (req_opts->is_inbound)
770 			data_size -= hash_parms->digestsize;
771 		offset_iv = aead_parms->assoc_size + data_size;
772 		cipher_len = 0;
773 		cipher_offset = offset_iv;
774 		auth_len = cipher_offset + aead_parms->data_pad_len;
775 	}
776 
777 	/* write in the total sctx length now that we know it */
778 	protocol_bits |= sctx_words;
779 
780 	/* Endian adjust the SCTX */
781 	spuh->sa.proto_flags = cpu_to_be32(protocol_bits);
782 	spuh->sa.cipher_flags = cpu_to_be32(cipher_bits);
783 	spuh->sa.ecf = cpu_to_be32(ecf_bits);
784 
785 	/* === create the BDESC section === */
786 	bdesc = (struct BDESC_HEADER *)ptr;
787 
788 	bdesc->offset_mac = cpu_to_be16(auth_offset);
789 	bdesc->length_mac = cpu_to_be16(auth_len);
790 	bdesc->offset_crypto = cpu_to_be16(cipher_offset);
791 	bdesc->length_crypto = cpu_to_be16(cipher_len);
792 
793 	/*
794 	 * CCM in SPU-M requires that ICV not be in same 32-bit word as data or
795 	 * padding.  So account for padding as necessary.
796 	 */
797 	if (cipher_parms->mode == CIPHER_MODE_CCM)
798 		auth_len += spum_wordalign_padlen(auth_len);
799 
800 	bdesc->offset_icv = cpu_to_be16(auth_len);
801 	bdesc->offset_iv = cpu_to_be16(offset_iv);
802 
803 	ptr += sizeof(struct BDESC_HEADER);
804 	buf_len += sizeof(struct BDESC_HEADER);
805 
806 	/* === no MFM section === */
807 
808 	/* === create the BD section === */
809 
810 	/* add the BD header */
811 	bd = (struct BD_HEADER *)ptr;
812 	bd->size = cpu_to_be16(real_db_size);
813 	bd->prev_length = 0;
814 
815 	ptr += sizeof(struct BD_HEADER);
816 	buf_len += sizeof(struct BD_HEADER);
817 
818 	packet_dump("  SPU request header: ", spu_hdr, buf_len);
819 
820 	return buf_len;
821 }
822 
823 /**
824  * spum_cipher_req_init() - Build a SPU request message header, up to and
825  * including the BD header.
826  * @spu_hdr:      Start of SPU request header (MH)
827  * @cipher_parms: Parameters that describe the cipher request
828  *
829  * Construct the message starting at spu_hdr. Caller should allocate this buffer
830  * in DMA-able memory at least SPU_HEADER_ALLOC_LEN bytes long.
831  *
832  * Return: the length of the SPU header in bytes. 0 if an error occurs.
833  */
834 u16 spum_cipher_req_init(u8 *spu_hdr, struct spu_cipher_parms *cipher_parms)
835 {
836 	struct SPUHEADER *spuh;
837 	u32 protocol_bits = 0;
838 	u32 cipher_bits = 0;
839 	u32 ecf_bits = 0;
840 	u8 sctx_words = 0;
841 	u8 *ptr = spu_hdr;
842 
843 	flow_log("%s()\n", __func__);
844 	flow_log("  cipher alg:%u mode:%u type %u\n", cipher_parms->alg,
845 		 cipher_parms->mode, cipher_parms->type);
846 	flow_log("  cipher_iv_len: %u\n", cipher_parms->iv_len);
847 	flow_log("    key: %d\n", cipher_parms->key_len);
848 	flow_dump("    key: ", cipher_parms->key_buf, cipher_parms->key_len);
849 
850 	/* starting out: zero the header (plus some) */
851 	memset(spu_hdr, 0, sizeof(struct SPUHEADER));
852 	ptr += sizeof(struct SPUHEADER);
853 
854 	/* format master header word */
855 	/* Do not set the next bit even though the datasheet says to */
856 	spuh = (struct SPUHEADER *)spu_hdr;
857 
858 	spuh->mh.op_code = SPU_CRYPTO_OPERATION_GENERIC;
859 	spuh->mh.flags |= (MH_SCTX_PRES | MH_BDESC_PRES | MH_BD_PRES);
860 
861 	/* Format sctx word 0 (protocol_bits) */
862 	sctx_words = 3;		/* size in words */
863 
864 	/* copy the encryption keys in the SAD entry */
865 	if (cipher_parms->alg) {
866 		if (cipher_parms->key_len) {
867 			ptr += cipher_parms->key_len;
868 			sctx_words += cipher_parms->key_len / 4;
869 		}
870 
871 		/*
872 		 * if encrypting then set IV size, use SCTX IV unless no IV
873 		 * given here
874 		 */
875 		if (cipher_parms->iv_len) {
876 			/* Use SCTX IV */
877 			ecf_bits |= SCTX_IV;
878 			ptr += cipher_parms->iv_len;
879 			sctx_words += cipher_parms->iv_len / 4;
880 		}
881 	}
882 
883 	/* Set the crypto parameters in the cipher.flags */
884 	cipher_bits |= cipher_parms->alg << CIPHER_ALG_SHIFT;
885 	cipher_bits |= cipher_parms->mode << CIPHER_MODE_SHIFT;
886 	cipher_bits |= cipher_parms->type << CIPHER_TYPE_SHIFT;
887 
888 	/* copy the encryption keys in the SAD entry */
889 	if (cipher_parms->alg && cipher_parms->key_len)
890 		memcpy(spuh + 1, cipher_parms->key_buf, cipher_parms->key_len);
891 
892 	/* write in the total sctx length now that we know it */
893 	protocol_bits |= sctx_words;
894 
895 	/* Endian adjust the SCTX */
896 	spuh->sa.proto_flags = cpu_to_be32(protocol_bits);
897 
898 	/* Endian adjust the SCTX */
899 	spuh->sa.cipher_flags = cpu_to_be32(cipher_bits);
900 	spuh->sa.ecf = cpu_to_be32(ecf_bits);
901 
902 	packet_dump("  SPU request header: ", spu_hdr,
903 		    sizeof(struct SPUHEADER));
904 
905 	return sizeof(struct SPUHEADER) + cipher_parms->key_len +
906 		cipher_parms->iv_len + sizeof(struct BDESC_HEADER) +
907 		sizeof(struct BD_HEADER);
908 }
909 
910 /**
911  * spum_cipher_req_finish() - Finish building a SPU request message header for a
912  * block cipher request. Assumes much of the header was already filled in at
913  * setkey() time in spu_cipher_req_init().
914  * @spu_hdr:         Start of the request message header (MH field)
915  * @spu_req_hdr_len: Length in bytes of the SPU request header
916  * @isInbound:       0 encrypt, 1 decrypt
917  * @cipher_parms:    Parameters describing cipher operation to be performed
918  * @data_size:       Length of the data in the BD field
919  *
920  * Assumes much of the header was already filled in at setkey() time in
921  * spum_cipher_req_init().
922  * spum_cipher_req_init() fills in the encryption key.
923  */
924 void spum_cipher_req_finish(u8 *spu_hdr,
925 			    u16 spu_req_hdr_len,
926 			    unsigned int is_inbound,
927 			    struct spu_cipher_parms *cipher_parms,
928 			    unsigned int data_size)
929 {
930 	struct SPUHEADER *spuh;
931 	struct BDESC_HEADER *bdesc;
932 	struct BD_HEADER *bd;
933 	u8 *bdesc_ptr = spu_hdr + spu_req_hdr_len -
934 	    (sizeof(struct BD_HEADER) + sizeof(struct BDESC_HEADER));
935 
936 	u32 cipher_bits;
937 
938 	flow_log("%s()\n", __func__);
939 	flow_log(" in: %u\n", is_inbound);
940 	flow_log(" cipher alg: %u, cipher_type: %u\n", cipher_parms->alg,
941 		 cipher_parms->type);
942 
943 	/*
944 	 * In XTS mode, API puts "i" parameter (block tweak) in IV.  For
945 	 * SPU-M, should be in start of the BD; tx_sg_create() copies it there.
946 	 * IV in SPU msg for SPU-M should be 0, since that's the "j" parameter
947 	 * (block ctr within larger data unit) - given we can send entire disk
948 	 * block (<= 4KB) in 1 SPU msg, don't need to use this parameter.
949 	 */
950 	if (cipher_parms->mode == CIPHER_MODE_XTS)
951 		memset(cipher_parms->iv_buf, 0, cipher_parms->iv_len);
952 
953 	flow_log(" iv len: %d\n", cipher_parms->iv_len);
954 	flow_dump("    iv: ", cipher_parms->iv_buf, cipher_parms->iv_len);
955 	flow_log(" data_size: %u\n", data_size);
956 
957 	/* format master header word */
958 	/* Do not set the next bit even though the datasheet says to */
959 	spuh = (struct SPUHEADER *)spu_hdr;
960 
961 	/* cipher_bits was initialized at setkey time */
962 	cipher_bits = be32_to_cpu(spuh->sa.cipher_flags);
963 
964 	/* Format sctx word 1 (cipher_bits) */
965 	if (is_inbound)
966 		cipher_bits |= CIPHER_INBOUND;
967 	else
968 		cipher_bits &= ~CIPHER_INBOUND;
969 
970 	if (cipher_parms->alg && cipher_parms->iv_buf && cipher_parms->iv_len)
971 		/* cipher iv provided so put it in here */
972 		memcpy(bdesc_ptr - cipher_parms->iv_len, cipher_parms->iv_buf,
973 		       cipher_parms->iv_len);
974 
975 	spuh->sa.cipher_flags = cpu_to_be32(cipher_bits);
976 
977 	/* === create the BDESC section === */
978 	bdesc = (struct BDESC_HEADER *)bdesc_ptr;
979 	bdesc->offset_mac = 0;
980 	bdesc->length_mac = 0;
981 	bdesc->offset_crypto = 0;
982 
983 	/* XTS mode, data_size needs to include tweak parameter */
984 	if (cipher_parms->mode == CIPHER_MODE_XTS)
985 		bdesc->length_crypto = cpu_to_be16(data_size +
986 						  SPU_XTS_TWEAK_SIZE);
987 	else
988 		bdesc->length_crypto = cpu_to_be16(data_size);
989 
990 	bdesc->offset_icv = 0;
991 	bdesc->offset_iv = 0;
992 
993 	/* === no MFM section === */
994 
995 	/* === create the BD section === */
996 	/* add the BD header */
997 	bd = (struct BD_HEADER *)(bdesc_ptr + sizeof(struct BDESC_HEADER));
998 	bd->size = cpu_to_be16(data_size);
999 
1000 	/* XTS mode, data_size needs to include tweak parameter */
1001 	if (cipher_parms->mode == CIPHER_MODE_XTS)
1002 		bd->size = cpu_to_be16(data_size + SPU_XTS_TWEAK_SIZE);
1003 	else
1004 		bd->size = cpu_to_be16(data_size);
1005 
1006 	bd->prev_length = 0;
1007 
1008 	packet_dump("  SPU request header: ", spu_hdr, spu_req_hdr_len);
1009 }
1010 
1011 /**
1012  * spum_request_pad() - Create pad bytes at the end of the data.
1013  * @pad_start:		Start of buffer where pad bytes are to be written
1014  * @gcm_ccm_padding:	length of GCM/CCM padding, in bytes
1015  * @hash_pad_len:	Number of bytes of padding extend data to full block
1016  * @auth_alg:		authentication algorithm
1017  * @auth_mode:		authentication mode
1018  * @total_sent:		length inserted at end of hash pad
1019  * @status_padding:	Number of bytes of padding to align STATUS word
1020  *
1021  * There may be three forms of pad:
1022  *  1. GCM/CCM pad - for GCM/CCM mode ciphers, pad to 16-byte alignment
1023  *  2. hash pad - pad to a block length, with 0x80 data terminator and
1024  *                size at the end
1025  *  3. STAT pad - to ensure the STAT field is 4-byte aligned
1026  */
1027 void spum_request_pad(u8 *pad_start,
1028 		      u32 gcm_ccm_padding,
1029 		      u32 hash_pad_len,
1030 		      enum hash_alg auth_alg,
1031 		      enum hash_mode auth_mode,
1032 		      unsigned int total_sent, u32 status_padding)
1033 {
1034 	u8 *ptr = pad_start;
1035 
1036 	/* fix data alignent for GCM/CCM */
1037 	if (gcm_ccm_padding > 0) {
1038 		flow_log("  GCM: padding to 16 byte alignment: %u bytes\n",
1039 			 gcm_ccm_padding);
1040 		memset(ptr, 0, gcm_ccm_padding);
1041 		ptr += gcm_ccm_padding;
1042 	}
1043 
1044 	if (hash_pad_len > 0) {
1045 		/* clear the padding section */
1046 		memset(ptr, 0, hash_pad_len);
1047 
1048 		if ((auth_alg == HASH_ALG_AES) &&
1049 		    (auth_mode == HASH_MODE_XCBC)) {
1050 			/* AES/XCBC just requires padding to be 0s */
1051 			ptr += hash_pad_len;
1052 		} else {
1053 			/* terminate the data */
1054 			*ptr = 0x80;
1055 			ptr += (hash_pad_len - sizeof(u64));
1056 
1057 			/* add the size at the end as required per alg */
1058 			if (auth_alg == HASH_ALG_MD5)
1059 				*(u64 *)ptr = cpu_to_le64((u64)total_sent * 8);
1060 			else		/* SHA1, SHA2-224, SHA2-256 */
1061 				*(u64 *)ptr = cpu_to_be64((u64)total_sent * 8);
1062 			ptr += sizeof(u64);
1063 		}
1064 	}
1065 
1066 	/* pad to a 4byte alignment for STAT */
1067 	if (status_padding > 0) {
1068 		flow_log("  STAT: padding to 4 byte alignment: %u bytes\n",
1069 			 status_padding);
1070 
1071 		memset(ptr, 0, status_padding);
1072 		ptr += status_padding;
1073 	}
1074 }
1075 
1076 /**
1077  * spum_xts_tweak_in_payload() - Indicate that SPUM DOES place the XTS tweak
1078  * field in the packet payload (rather than using IV)
1079  *
1080  * Return: 1
1081  */
1082 u8 spum_xts_tweak_in_payload(void)
1083 {
1084 	return 1;
1085 }
1086 
1087 /**
1088  * spum_tx_status_len() - Return the length of the STATUS field in a SPU
1089  * response message.
1090  *
1091  * Return: Length of STATUS field in bytes.
1092  */
1093 u8 spum_tx_status_len(void)
1094 {
1095 	return SPU_TX_STATUS_LEN;
1096 }
1097 
1098 /**
1099  * spum_rx_status_len() - Return the length of the STATUS field in a SPU
1100  * response message.
1101  *
1102  * Return: Length of STATUS field in bytes.
1103  */
1104 u8 spum_rx_status_len(void)
1105 {
1106 	return SPU_RX_STATUS_LEN;
1107 }
1108 
1109 /**
1110  * spum_status_process() - Process the status from a SPU response message.
1111  * @statp:  start of STATUS word
1112  * Return:
1113  *   0 - if status is good and response should be processed
1114  *   !0 - status indicates an error and response is invalid
1115  */
1116 int spum_status_process(u8 *statp)
1117 {
1118 	u32 status;
1119 
1120 	status = __be32_to_cpu(*(__be32 *)statp);
1121 	flow_log("SPU response STATUS %#08x\n", status);
1122 	if (status & SPU_STATUS_ERROR_FLAG) {
1123 		pr_err("%s() Warning: Error result from SPU: %#08x\n",
1124 		       __func__, status);
1125 		if (status & SPU_STATUS_INVALID_ICV)
1126 			return SPU_INVALID_ICV;
1127 		return -EBADMSG;
1128 	}
1129 	return 0;
1130 }
1131 
1132 /**
1133  * spum_ccm_update_iv() - Update the IV as per the requirements for CCM mode.
1134  *
1135  * @digestsize:		Digest size of this request
1136  * @cipher_parms:	(pointer to) cipher parmaeters, includes IV buf & IV len
1137  * @assoclen:		Length of AAD data
1138  * @chunksize:		length of input data to be sent in this req
1139  * @is_encrypt:		true if this is an output/encrypt operation
1140  * @is_esp:		true if this is an ESP / RFC4309 operation
1141  *
1142  */
1143 void spum_ccm_update_iv(unsigned int digestsize,
1144 			struct spu_cipher_parms *cipher_parms,
1145 			unsigned int assoclen,
1146 			unsigned int chunksize,
1147 			bool is_encrypt,
1148 			bool is_esp)
1149 {
1150 	u8 L;		/* L from CCM algorithm, length of plaintext data */
1151 	u8 mprime;	/* M' from CCM algo, (M - 2) / 2, where M=authsize */
1152 	u8 adata;
1153 
1154 	if (cipher_parms->iv_len != CCM_AES_IV_SIZE) {
1155 		pr_err("%s(): Invalid IV len %d for CCM mode, should be %d\n",
1156 		       __func__, cipher_parms->iv_len, CCM_AES_IV_SIZE);
1157 		return;
1158 	}
1159 
1160 	/*
1161 	 * IV needs to be formatted as follows:
1162 	 *
1163 	 * |          Byte 0               | Bytes 1 - N | Bytes (N+1) - 15 |
1164 	 * | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | Bits 7 - 0  |    Bits 7 - 0    |
1165 	 * | 0 |Ad?|(M - 2) / 2|   L - 1   |    Nonce    | Plaintext Length |
1166 	 *
1167 	 * Ad? = 1 if AAD present, 0 if not present
1168 	 * M = size of auth field, 8, 12, or 16 bytes (SPU-M) -or-
1169 	 *                         4, 6, 8, 10, 12, 14, 16 bytes (SPU2)
1170 	 * L = Size of Plaintext Length field; Nonce size = 15 - L
1171 	 *
1172 	 * It appears that the crypto API already expects the L-1 portion
1173 	 * to be set in the first byte of the IV, which implicitly determines
1174 	 * the nonce size, and also fills in the nonce.  But the other bits
1175 	 * in byte 0 as well as the plaintext length need to be filled in.
1176 	 *
1177 	 * In rfc4309/esp mode, L is not already in the supplied IV and
1178 	 * we need to fill it in, as well as move the IV data to be after
1179 	 * the salt
1180 	 */
1181 	if (is_esp) {
1182 		L = CCM_ESP_L_VALUE;	/* RFC4309 has fixed L */
1183 	} else {
1184 		/* L' = plaintext length - 1 so Plaintext length is L' + 1 */
1185 		L = ((cipher_parms->iv_buf[0] & CCM_B0_L_PRIME) >>
1186 		      CCM_B0_L_PRIME_SHIFT) + 1;
1187 	}
1188 
1189 	mprime = (digestsize - 2) >> 1;  /* M' = (M - 2) / 2 */
1190 	adata = (assoclen > 0);  /* adata = 1 if any associated data */
1191 
1192 	cipher_parms->iv_buf[0] = (adata << CCM_B0_ADATA_SHIFT) |
1193 				  (mprime << CCM_B0_M_PRIME_SHIFT) |
1194 				  ((L - 1) << CCM_B0_L_PRIME_SHIFT);
1195 
1196 	/* Nonce is already filled in by crypto API, and is 15 - L bytes */
1197 
1198 	/* Don't include digest in plaintext size when decrypting */
1199 	if (!is_encrypt)
1200 		chunksize -= digestsize;
1201 
1202 	/* Fill in length of plaintext, formatted to be L bytes long */
1203 	format_value_ccm(chunksize, &cipher_parms->iv_buf[15 - L + 1], L);
1204 }
1205 
1206 /**
1207  * spum_wordalign_padlen() - Given the length of a data field, determine the
1208  * padding required to align the data following this field on a 4-byte boundary.
1209  * @data_size: length of data field in bytes
1210  *
1211  * Return: length of status field padding, in bytes
1212  */
1213 u32 spum_wordalign_padlen(u32 data_size)
1214 {
1215 	return ((data_size + 3) & ~3) - data_size;
1216 }
1217