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_cpup((__be32 *)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 struct BDESC_HEADER *bdesc = (struct BDESC_HEADER *)ptr; 277 278 packet_log(" BDESC[0] 0x%08x\n", be32_to_cpup((__be32 *)ptr)); 279 packet_log(" OffsetMAC:%u LengthMAC:%u\n", 280 be16_to_cpu(bdesc->offset_mac), 281 be16_to_cpu(bdesc->length_mac)); 282 ptr += sizeof(u32); 283 284 packet_log(" BDESC[1] 0x%08x\n", be32_to_cpup((__be32 *)ptr)); 285 packet_log(" OffsetCrypto:%u LengthCrypto:%u\n", 286 be16_to_cpu(bdesc->offset_crypto), 287 be16_to_cpu(bdesc->length_crypto)); 288 ptr += sizeof(u32); 289 290 packet_log(" BDESC[2] 0x%08x\n", be32_to_cpup((__be32 *)ptr)); 291 packet_log(" OffsetICV:%u OffsetIV:%u\n", 292 be16_to_cpu(bdesc->offset_icv), 293 be16_to_cpu(bdesc->offset_iv)); 294 ptr += sizeof(u32); 295 } 296 297 /* ========== Decode BD ========== */ 298 if (spuh->mh.flags & MH_BD_PRES) { 299 struct BD_HEADER *bd = (struct BD_HEADER *)ptr; 300 301 packet_log(" BD[0] 0x%08x\n", be32_to_cpup((__be32 *)ptr)); 302 packet_log(" Size:%ubytes PrevLength:%u\n", 303 be16_to_cpu(bd->size), be16_to_cpu(bd->prev_length)); 304 ptr += 4; 305 } 306 307 /* Double check sanity */ 308 if (buf + buf_len != ptr) { 309 packet_log(" Packet parsed incorrectly. "); 310 packet_log("buf:%p buf_len:%u buf+buf_len:%p ptr:%p\n", 311 buf, buf_len, buf + buf_len, ptr); 312 } 313 314 packet_log("\n"); 315 } 316 317 /** 318 * spum_ns2_ctx_max_payload() - Determine the max length of the payload for a 319 * SPU message for a given cipher and hash alg context. 320 * @cipher_alg: The cipher algorithm 321 * @cipher_mode: The cipher mode 322 * @blocksize: The size of a block of data for this algo 323 * 324 * The max payload must be a multiple of the blocksize so that if a request is 325 * too large to fit in a single SPU message, the request can be broken into 326 * max_payload sized chunks. Each chunk must be a multiple of blocksize. 327 * 328 * Return: Max payload length in bytes 329 */ 330 u32 spum_ns2_ctx_max_payload(enum spu_cipher_alg cipher_alg, 331 enum spu_cipher_mode cipher_mode, 332 unsigned int blocksize) 333 { 334 u32 max_payload = SPUM_NS2_MAX_PAYLOAD; 335 u32 excess; 336 337 /* In XTS on SPU-M, we'll need to insert tweak before input data */ 338 if (cipher_mode == CIPHER_MODE_XTS) 339 max_payload -= SPU_XTS_TWEAK_SIZE; 340 341 excess = max_payload % blocksize; 342 343 return max_payload - excess; 344 } 345 346 /** 347 * spum_nsp_ctx_max_payload() - Determine the max length of the payload for a 348 * SPU message for a given cipher and hash alg context. 349 * @cipher_alg: The cipher algorithm 350 * @cipher_mode: The cipher mode 351 * @blocksize: The size of a block of data for this algo 352 * 353 * The max payload must be a multiple of the blocksize so that if a request is 354 * too large to fit in a single SPU message, the request can be broken into 355 * max_payload sized chunks. Each chunk must be a multiple of blocksize. 356 * 357 * Return: Max payload length in bytes 358 */ 359 u32 spum_nsp_ctx_max_payload(enum spu_cipher_alg cipher_alg, 360 enum spu_cipher_mode cipher_mode, 361 unsigned int blocksize) 362 { 363 u32 max_payload = SPUM_NSP_MAX_PAYLOAD; 364 u32 excess; 365 366 /* In XTS on SPU-M, we'll need to insert tweak before input data */ 367 if (cipher_mode == CIPHER_MODE_XTS) 368 max_payload -= SPU_XTS_TWEAK_SIZE; 369 370 excess = max_payload % blocksize; 371 372 return max_payload - excess; 373 } 374 375 /** spum_payload_length() - Given a SPU-M message header, extract the payload 376 * length. 377 * @spu_hdr: Start of SPU header 378 * 379 * Assumes just MH, EMH, BD (no SCTX, BDESC. Works for response frames. 380 * 381 * Return: payload length in bytes 382 */ 383 u32 spum_payload_length(u8 *spu_hdr) 384 { 385 struct BD_HEADER *bd; 386 u32 pl_len; 387 388 /* Find BD header. skip MH, EMH */ 389 bd = (struct BD_HEADER *)(spu_hdr + 8); 390 pl_len = be16_to_cpu(bd->size); 391 392 return pl_len; 393 } 394 395 /** 396 * spum_response_hdr_len() - Given the length of the hash key and encryption 397 * key, determine the expected length of a SPU response header. 398 * @auth_key_len: authentication key length (bytes) 399 * @enc_key_len: encryption key length (bytes) 400 * @is_hash: true if response message is for a hash operation 401 * 402 * Return: length of SPU response header (bytes) 403 */ 404 u16 spum_response_hdr_len(u16 auth_key_len, u16 enc_key_len, bool is_hash) 405 { 406 if (is_hash) 407 return SPU_HASH_RESP_HDR_LEN; 408 else 409 return SPU_RESP_HDR_LEN; 410 } 411 412 /** 413 * spum_hash_pad_len() - Calculate the length of hash padding required to extend 414 * data to a full block size. 415 * @hash_alg: hash algorithm 416 * @hash_mode: hash mode 417 * @chunksize: length of data, in bytes 418 * @hash_block_size: size of a block of data for hash algorithm 419 * 420 * Reserve space for 1 byte (0x80) start of pad and the total length as u64 421 * 422 * Return: length of hash pad in bytes 423 */ 424 u16 spum_hash_pad_len(enum hash_alg hash_alg, enum hash_mode hash_mode, 425 u32 chunksize, u16 hash_block_size) 426 { 427 unsigned int length_len; 428 unsigned int used_space_last_block; 429 int hash_pad_len; 430 431 /* AES-XCBC hash requires just padding to next block boundary */ 432 if ((hash_alg == HASH_ALG_AES) && (hash_mode == HASH_MODE_XCBC)) { 433 used_space_last_block = chunksize % hash_block_size; 434 hash_pad_len = hash_block_size - used_space_last_block; 435 if (hash_pad_len >= hash_block_size) 436 hash_pad_len -= hash_block_size; 437 return hash_pad_len; 438 } 439 440 used_space_last_block = chunksize % hash_block_size + 1; 441 if ((hash_alg == HASH_ALG_SHA384) || (hash_alg == HASH_ALG_SHA512)) 442 length_len = 2 * sizeof(u64); 443 else 444 length_len = sizeof(u64); 445 446 used_space_last_block += length_len; 447 hash_pad_len = hash_block_size - used_space_last_block; 448 if (hash_pad_len < 0) 449 hash_pad_len += hash_block_size; 450 451 hash_pad_len += 1 + length_len; 452 return hash_pad_len; 453 } 454 455 /** 456 * spum_gcm_ccm_pad_len() - Determine the required length of GCM or CCM padding. 457 * @cipher_mode: Algo type 458 * @data_size: Length of plaintext (bytes) 459 * 460 * Return: Length of padding, in bytes 461 */ 462 u32 spum_gcm_ccm_pad_len(enum spu_cipher_mode cipher_mode, 463 unsigned int data_size) 464 { 465 u32 pad_len = 0; 466 u32 m1 = SPU_GCM_CCM_ALIGN - 1; 467 468 if ((cipher_mode == CIPHER_MODE_GCM) || 469 (cipher_mode == CIPHER_MODE_CCM)) 470 pad_len = ((data_size + m1) & ~m1) - data_size; 471 472 return pad_len; 473 } 474 475 /** 476 * spum_assoc_resp_len() - Determine the size of the receive buffer required to 477 * catch associated data. 478 * @cipher_mode: cipher mode 479 * @assoc_len: length of associated data (bytes) 480 * @iv_len: length of IV (bytes) 481 * @is_encrypt: true if encrypting. false if decrypting. 482 * 483 * Return: length of associated data in response message (bytes) 484 */ 485 u32 spum_assoc_resp_len(enum spu_cipher_mode cipher_mode, 486 unsigned int assoc_len, unsigned int iv_len, 487 bool is_encrypt) 488 { 489 u32 buflen = 0; 490 u32 pad; 491 492 if (assoc_len) 493 buflen = assoc_len; 494 495 if (cipher_mode == CIPHER_MODE_GCM) { 496 /* AAD needs to be padded in responses too */ 497 pad = spum_gcm_ccm_pad_len(cipher_mode, buflen); 498 buflen += pad; 499 } 500 if (cipher_mode == CIPHER_MODE_CCM) { 501 /* 502 * AAD needs to be padded in responses too 503 * for CCM, len + 2 needs to be 128-bit aligned. 504 */ 505 pad = spum_gcm_ccm_pad_len(cipher_mode, buflen + 2); 506 buflen += pad; 507 } 508 509 return buflen; 510 } 511 512 /** 513 * spum_aead_ivlen() - Calculate the length of the AEAD IV to be included 514 * in a SPU request after the AAD and before the payload. 515 * @cipher_mode: cipher mode 516 * @iv_len: initialization vector length in bytes 517 * 518 * In Linux ~4.2 and later, the assoc_data sg includes the IV. So no need 519 * to include the IV as a separate field in the SPU request msg. 520 * 521 * Return: Length of AEAD IV in bytes 522 */ 523 u8 spum_aead_ivlen(enum spu_cipher_mode cipher_mode, u16 iv_len) 524 { 525 return 0; 526 } 527 528 /** 529 * spum_hash_type() - Determine the type of hash operation. 530 * @src_sent: The number of bytes in the current request that have already 531 * been sent to the SPU to be hashed. 532 * 533 * We do not use HASH_TYPE_FULL for requests that fit in a single SPU message. 534 * Using FULL causes failures (such as when the string to be hashed is empty). 535 * For similar reasons, we never use HASH_TYPE_FIN. Instead, submit messages 536 * as INIT or UPDT and do the hash padding in sw. 537 */ 538 enum hash_type spum_hash_type(u32 src_sent) 539 { 540 return src_sent ? HASH_TYPE_UPDT : HASH_TYPE_INIT; 541 } 542 543 /** 544 * spum_digest_size() - Determine the size of a hash digest to expect the SPU to 545 * return. 546 * @alg_digest_size: Number of bytes in the final digest for the given algo 547 * @alg: The hash algorithm 548 * @htype: Type of hash operation (init, update, full, etc) 549 * 550 * When doing incremental hashing for an algorithm with a truncated hash 551 * (e.g., SHA224), the SPU returns the full digest so that it can be fed back as 552 * a partial result for the next chunk. 553 */ 554 u32 spum_digest_size(u32 alg_digest_size, enum hash_alg alg, 555 enum hash_type htype) 556 { 557 u32 digestsize = alg_digest_size; 558 559 /* SPU returns complete digest when doing incremental hash and truncated 560 * hash algo. 561 */ 562 if ((htype == HASH_TYPE_INIT) || (htype == HASH_TYPE_UPDT)) { 563 if (alg == HASH_ALG_SHA224) 564 digestsize = SHA256_DIGEST_SIZE; 565 else if (alg == HASH_ALG_SHA384) 566 digestsize = SHA512_DIGEST_SIZE; 567 } 568 return digestsize; 569 } 570 571 /** 572 * spum_create_request() - Build a SPU request message header, up to and 573 * including the BD header. Construct the message starting at spu_hdr. Caller 574 * should allocate this buffer in DMA-able memory at least SPU_HEADER_ALLOC_LEN 575 * bytes long. 576 * @spu_hdr: Start of buffer where SPU request header is to be written 577 * @req_opts: SPU request message options 578 * @cipher_parms: Parameters related to cipher algorithm 579 * @hash_parms: Parameters related to hash algorithm 580 * @aead_parms: Parameters related to AEAD operation 581 * @data_size: Length of data to be encrypted or authenticated. If AEAD, does 582 * not include length of AAD. 583 * 584 * Return: the length of the SPU header in bytes. 0 if an error occurs. 585 */ 586 u32 spum_create_request(u8 *spu_hdr, 587 struct spu_request_opts *req_opts, 588 struct spu_cipher_parms *cipher_parms, 589 struct spu_hash_parms *hash_parms, 590 struct spu_aead_parms *aead_parms, 591 unsigned int data_size) 592 { 593 struct SPUHEADER *spuh; 594 struct BDESC_HEADER *bdesc; 595 struct BD_HEADER *bd; 596 597 u8 *ptr; 598 u32 protocol_bits = 0; 599 u32 cipher_bits = 0; 600 u32 ecf_bits = 0; 601 u8 sctx_words = 0; 602 unsigned int buf_len = 0; 603 604 /* size of the cipher payload */ 605 unsigned int cipher_len = hash_parms->prebuf_len + data_size + 606 hash_parms->pad_len; 607 608 /* offset of prebuf or data from end of BD header */ 609 unsigned int cipher_offset = aead_parms->assoc_size + 610 aead_parms->iv_len + aead_parms->aad_pad_len; 611 612 /* total size of the DB data (without STAT word padding) */ 613 unsigned int real_db_size = spu_real_db_size(aead_parms->assoc_size, 614 aead_parms->iv_len, 615 hash_parms->prebuf_len, 616 data_size, 617 aead_parms->aad_pad_len, 618 aead_parms->data_pad_len, 619 hash_parms->pad_len); 620 621 unsigned int auth_offset = 0; 622 unsigned int offset_iv = 0; 623 624 /* size/offset of the auth payload */ 625 unsigned int auth_len; 626 627 auth_len = real_db_size; 628 629 if (req_opts->is_aead && req_opts->is_inbound) 630 cipher_len -= hash_parms->digestsize; 631 632 if (req_opts->is_aead && req_opts->is_inbound) 633 auth_len -= hash_parms->digestsize; 634 635 if ((hash_parms->alg == HASH_ALG_AES) && 636 (hash_parms->mode == HASH_MODE_XCBC)) { 637 auth_len -= hash_parms->pad_len; 638 cipher_len -= hash_parms->pad_len; 639 } 640 641 flow_log("%s()\n", __func__); 642 flow_log(" in:%u authFirst:%u\n", 643 req_opts->is_inbound, req_opts->auth_first); 644 flow_log(" %s. cipher alg:%u mode:%u type %u\n", 645 spu_alg_name(cipher_parms->alg, cipher_parms->mode), 646 cipher_parms->alg, cipher_parms->mode, cipher_parms->type); 647 flow_log(" key: %d\n", cipher_parms->key_len); 648 flow_dump(" key: ", cipher_parms->key_buf, cipher_parms->key_len); 649 flow_log(" iv: %d\n", cipher_parms->iv_len); 650 flow_dump(" iv: ", cipher_parms->iv_buf, cipher_parms->iv_len); 651 flow_log(" auth alg:%u mode:%u type %u\n", 652 hash_parms->alg, hash_parms->mode, hash_parms->type); 653 flow_log(" digestsize: %u\n", hash_parms->digestsize); 654 flow_log(" authkey: %d\n", hash_parms->key_len); 655 flow_dump(" authkey: ", hash_parms->key_buf, hash_parms->key_len); 656 flow_log(" assoc_size:%u\n", aead_parms->assoc_size); 657 flow_log(" prebuf_len:%u\n", hash_parms->prebuf_len); 658 flow_log(" data_size:%u\n", data_size); 659 flow_log(" hash_pad_len:%u\n", hash_parms->pad_len); 660 flow_log(" real_db_size:%u\n", real_db_size); 661 flow_log(" auth_offset:%u auth_len:%u cipher_offset:%u cipher_len:%u\n", 662 auth_offset, auth_len, cipher_offset, cipher_len); 663 flow_log(" aead_iv: %u\n", aead_parms->iv_len); 664 665 /* starting out: zero the header (plus some) */ 666 ptr = spu_hdr; 667 memset(ptr, 0, sizeof(struct SPUHEADER)); 668 669 /* format master header word */ 670 /* Do not set the next bit even though the datasheet says to */ 671 spuh = (struct SPUHEADER *)ptr; 672 ptr += sizeof(struct SPUHEADER); 673 buf_len += sizeof(struct SPUHEADER); 674 675 spuh->mh.op_code = SPU_CRYPTO_OPERATION_GENERIC; 676 spuh->mh.flags |= (MH_SCTX_PRES | MH_BDESC_PRES | MH_BD_PRES); 677 678 /* Format sctx word 0 (protocol_bits) */ 679 sctx_words = 3; /* size in words */ 680 681 /* Format sctx word 1 (cipher_bits) */ 682 if (req_opts->is_inbound) 683 cipher_bits |= CIPHER_INBOUND; 684 if (req_opts->auth_first) 685 cipher_bits |= CIPHER_ORDER; 686 687 /* Set the crypto parameters in the cipher.flags */ 688 cipher_bits |= cipher_parms->alg << CIPHER_ALG_SHIFT; 689 cipher_bits |= cipher_parms->mode << CIPHER_MODE_SHIFT; 690 cipher_bits |= cipher_parms->type << CIPHER_TYPE_SHIFT; 691 692 /* Set the auth parameters in the cipher.flags */ 693 cipher_bits |= hash_parms->alg << HASH_ALG_SHIFT; 694 cipher_bits |= hash_parms->mode << HASH_MODE_SHIFT; 695 cipher_bits |= hash_parms->type << HASH_TYPE_SHIFT; 696 697 /* 698 * Format sctx extensions if required, and update main fields if 699 * required) 700 */ 701 if (hash_parms->alg) { 702 /* Write the authentication key material if present */ 703 if (hash_parms->key_len) { 704 memcpy(ptr, hash_parms->key_buf, hash_parms->key_len); 705 ptr += hash_parms->key_len; 706 buf_len += hash_parms->key_len; 707 sctx_words += hash_parms->key_len / 4; 708 } 709 710 if ((cipher_parms->mode == CIPHER_MODE_GCM) || 711 (cipher_parms->mode == CIPHER_MODE_CCM)) 712 /* unpadded length */ 713 offset_iv = aead_parms->assoc_size; 714 715 /* if GCM/CCM we need to write ICV into the payload */ 716 if (!req_opts->is_inbound) { 717 if ((cipher_parms->mode == CIPHER_MODE_GCM) || 718 (cipher_parms->mode == CIPHER_MODE_CCM)) 719 ecf_bits |= 1 << INSERT_ICV_SHIFT; 720 } else { 721 ecf_bits |= CHECK_ICV; 722 } 723 724 /* Inform the SPU of the ICV size (in words) */ 725 if (hash_parms->digestsize == 64) 726 cipher_bits |= ICV_IS_512; 727 else 728 ecf_bits |= 729 (hash_parms->digestsize / 4) << ICV_SIZE_SHIFT; 730 } 731 732 if (req_opts->bd_suppress) 733 ecf_bits |= BD_SUPPRESS; 734 735 /* copy the encryption keys in the SAD entry */ 736 if (cipher_parms->alg) { 737 if (cipher_parms->key_len) { 738 memcpy(ptr, cipher_parms->key_buf, 739 cipher_parms->key_len); 740 ptr += cipher_parms->key_len; 741 buf_len += cipher_parms->key_len; 742 sctx_words += cipher_parms->key_len / 4; 743 } 744 745 /* 746 * if encrypting then set IV size, use SCTX IV unless no IV 747 * given here 748 */ 749 if (cipher_parms->iv_buf && cipher_parms->iv_len) { 750 /* Use SCTX IV */ 751 ecf_bits |= SCTX_IV; 752 753 /* cipher iv provided so put it in here */ 754 memcpy(ptr, cipher_parms->iv_buf, cipher_parms->iv_len); 755 756 ptr += cipher_parms->iv_len; 757 buf_len += cipher_parms->iv_len; 758 sctx_words += cipher_parms->iv_len / 4; 759 } 760 } 761 762 /* 763 * RFC4543 (GMAC/ESP) requires data to be sent as part of AAD 764 * so we need to override the BDESC parameters. 765 */ 766 if (req_opts->is_rfc4543) { 767 if (req_opts->is_inbound) 768 data_size -= hash_parms->digestsize; 769 offset_iv = aead_parms->assoc_size + data_size; 770 cipher_len = 0; 771 cipher_offset = offset_iv; 772 auth_len = cipher_offset + aead_parms->data_pad_len; 773 } 774 775 /* write in the total sctx length now that we know it */ 776 protocol_bits |= sctx_words; 777 778 /* Endian adjust the SCTX */ 779 spuh->sa.proto_flags = cpu_to_be32(protocol_bits); 780 spuh->sa.cipher_flags = cpu_to_be32(cipher_bits); 781 spuh->sa.ecf = cpu_to_be32(ecf_bits); 782 783 /* === create the BDESC section === */ 784 bdesc = (struct BDESC_HEADER *)ptr; 785 786 bdesc->offset_mac = cpu_to_be16(auth_offset); 787 bdesc->length_mac = cpu_to_be16(auth_len); 788 bdesc->offset_crypto = cpu_to_be16(cipher_offset); 789 bdesc->length_crypto = cpu_to_be16(cipher_len); 790 791 /* 792 * CCM in SPU-M requires that ICV not be in same 32-bit word as data or 793 * padding. So account for padding as necessary. 794 */ 795 if (cipher_parms->mode == CIPHER_MODE_CCM) 796 auth_len += spum_wordalign_padlen(auth_len); 797 798 bdesc->offset_icv = cpu_to_be16(auth_len); 799 bdesc->offset_iv = cpu_to_be16(offset_iv); 800 801 ptr += sizeof(struct BDESC_HEADER); 802 buf_len += sizeof(struct BDESC_HEADER); 803 804 /* === no MFM section === */ 805 806 /* === create the BD section === */ 807 808 /* add the BD header */ 809 bd = (struct BD_HEADER *)ptr; 810 bd->size = cpu_to_be16(real_db_size); 811 bd->prev_length = 0; 812 813 ptr += sizeof(struct BD_HEADER); 814 buf_len += sizeof(struct BD_HEADER); 815 816 packet_dump(" SPU request header: ", spu_hdr, buf_len); 817 818 return buf_len; 819 } 820 821 /** 822 * spum_cipher_req_init() - Build a SPU request message header, up to and 823 * including the BD header. 824 * @spu_hdr: Start of SPU request header (MH) 825 * @cipher_parms: Parameters that describe the cipher request 826 * 827 * Construct the message starting at spu_hdr. Caller should allocate this buffer 828 * in DMA-able memory at least SPU_HEADER_ALLOC_LEN bytes long. 829 * 830 * Return: the length of the SPU header in bytes. 0 if an error occurs. 831 */ 832 u16 spum_cipher_req_init(u8 *spu_hdr, struct spu_cipher_parms *cipher_parms) 833 { 834 struct SPUHEADER *spuh; 835 u32 protocol_bits = 0; 836 u32 cipher_bits = 0; 837 u32 ecf_bits = 0; 838 u8 sctx_words = 0; 839 u8 *ptr = spu_hdr; 840 841 flow_log("%s()\n", __func__); 842 flow_log(" cipher alg:%u mode:%u type %u\n", cipher_parms->alg, 843 cipher_parms->mode, cipher_parms->type); 844 flow_log(" cipher_iv_len: %u\n", cipher_parms->iv_len); 845 flow_log(" key: %d\n", cipher_parms->key_len); 846 flow_dump(" key: ", cipher_parms->key_buf, cipher_parms->key_len); 847 848 /* starting out: zero the header (plus some) */ 849 memset(spu_hdr, 0, sizeof(struct SPUHEADER)); 850 ptr += sizeof(struct SPUHEADER); 851 852 /* format master header word */ 853 /* Do not set the next bit even though the datasheet says to */ 854 spuh = (struct SPUHEADER *)spu_hdr; 855 856 spuh->mh.op_code = SPU_CRYPTO_OPERATION_GENERIC; 857 spuh->mh.flags |= (MH_SCTX_PRES | MH_BDESC_PRES | MH_BD_PRES); 858 859 /* Format sctx word 0 (protocol_bits) */ 860 sctx_words = 3; /* size in words */ 861 862 /* copy the encryption keys in the SAD entry */ 863 if (cipher_parms->alg) { 864 if (cipher_parms->key_len) { 865 ptr += cipher_parms->key_len; 866 sctx_words += cipher_parms->key_len / 4; 867 } 868 869 /* 870 * if encrypting then set IV size, use SCTX IV unless no IV 871 * given here 872 */ 873 if (cipher_parms->iv_len) { 874 /* Use SCTX IV */ 875 ecf_bits |= SCTX_IV; 876 ptr += cipher_parms->iv_len; 877 sctx_words += cipher_parms->iv_len / 4; 878 } 879 } 880 881 /* Set the crypto parameters in the cipher.flags */ 882 cipher_bits |= cipher_parms->alg << CIPHER_ALG_SHIFT; 883 cipher_bits |= cipher_parms->mode << CIPHER_MODE_SHIFT; 884 cipher_bits |= cipher_parms->type << CIPHER_TYPE_SHIFT; 885 886 /* copy the encryption keys in the SAD entry */ 887 if (cipher_parms->alg && cipher_parms->key_len) 888 memcpy(spuh + 1, cipher_parms->key_buf, cipher_parms->key_len); 889 890 /* write in the total sctx length now that we know it */ 891 protocol_bits |= sctx_words; 892 893 /* Endian adjust the SCTX */ 894 spuh->sa.proto_flags = cpu_to_be32(protocol_bits); 895 896 /* Endian adjust the SCTX */ 897 spuh->sa.cipher_flags = cpu_to_be32(cipher_bits); 898 spuh->sa.ecf = cpu_to_be32(ecf_bits); 899 900 packet_dump(" SPU request header: ", spu_hdr, 901 sizeof(struct SPUHEADER)); 902 903 return sizeof(struct SPUHEADER) + cipher_parms->key_len + 904 cipher_parms->iv_len + sizeof(struct BDESC_HEADER) + 905 sizeof(struct BD_HEADER); 906 } 907 908 /** 909 * spum_cipher_req_finish() - Finish building a SPU request message header for a 910 * block cipher request. Assumes much of the header was already filled in at 911 * setkey() time in spu_cipher_req_init(). 912 * @spu_hdr: Start of the request message header (MH field) 913 * @spu_req_hdr_len: Length in bytes of the SPU request header 914 * @is_inbound: 0 encrypt, 1 decrypt 915 * @cipher_parms: Parameters describing cipher operation to be performed 916 * @data_size: Length of the data in the BD field 917 * 918 * Assumes much of the header was already filled in at setkey() time in 919 * spum_cipher_req_init(). 920 * spum_cipher_req_init() fills in the encryption key. 921 */ 922 void spum_cipher_req_finish(u8 *spu_hdr, 923 u16 spu_req_hdr_len, 924 unsigned int is_inbound, 925 struct spu_cipher_parms *cipher_parms, 926 unsigned int data_size) 927 { 928 struct SPUHEADER *spuh; 929 struct BDESC_HEADER *bdesc; 930 struct BD_HEADER *bd; 931 u8 *bdesc_ptr = spu_hdr + spu_req_hdr_len - 932 (sizeof(struct BD_HEADER) + sizeof(struct BDESC_HEADER)); 933 934 u32 cipher_bits; 935 936 flow_log("%s()\n", __func__); 937 flow_log(" in: %u\n", is_inbound); 938 flow_log(" cipher alg: %u, cipher_type: %u\n", cipher_parms->alg, 939 cipher_parms->type); 940 941 /* 942 * In XTS mode, API puts "i" parameter (block tweak) in IV. For 943 * SPU-M, should be in start of the BD; tx_sg_create() copies it there. 944 * IV in SPU msg for SPU-M should be 0, since that's the "j" parameter 945 * (block ctr within larger data unit) - given we can send entire disk 946 * block (<= 4KB) in 1 SPU msg, don't need to use this parameter. 947 */ 948 if (cipher_parms->mode == CIPHER_MODE_XTS) 949 memset(cipher_parms->iv_buf, 0, cipher_parms->iv_len); 950 951 flow_log(" iv len: %d\n", cipher_parms->iv_len); 952 flow_dump(" iv: ", cipher_parms->iv_buf, cipher_parms->iv_len); 953 flow_log(" data_size: %u\n", data_size); 954 955 /* format master header word */ 956 /* Do not set the next bit even though the datasheet says to */ 957 spuh = (struct SPUHEADER *)spu_hdr; 958 959 /* cipher_bits was initialized at setkey time */ 960 cipher_bits = be32_to_cpu(spuh->sa.cipher_flags); 961 962 /* Format sctx word 1 (cipher_bits) */ 963 if (is_inbound) 964 cipher_bits |= CIPHER_INBOUND; 965 else 966 cipher_bits &= ~CIPHER_INBOUND; 967 968 if (cipher_parms->alg && cipher_parms->iv_buf && cipher_parms->iv_len) 969 /* cipher iv provided so put it in here */ 970 memcpy(bdesc_ptr - cipher_parms->iv_len, cipher_parms->iv_buf, 971 cipher_parms->iv_len); 972 973 spuh->sa.cipher_flags = cpu_to_be32(cipher_bits); 974 975 /* === create the BDESC section === */ 976 bdesc = (struct BDESC_HEADER *)bdesc_ptr; 977 bdesc->offset_mac = 0; 978 bdesc->length_mac = 0; 979 bdesc->offset_crypto = 0; 980 981 /* XTS mode, data_size needs to include tweak parameter */ 982 if (cipher_parms->mode == CIPHER_MODE_XTS) 983 bdesc->length_crypto = cpu_to_be16(data_size + 984 SPU_XTS_TWEAK_SIZE); 985 else 986 bdesc->length_crypto = cpu_to_be16(data_size); 987 988 bdesc->offset_icv = 0; 989 bdesc->offset_iv = 0; 990 991 /* === no MFM section === */ 992 993 /* === create the BD section === */ 994 /* add the BD header */ 995 bd = (struct BD_HEADER *)(bdesc_ptr + sizeof(struct BDESC_HEADER)); 996 bd->size = cpu_to_be16(data_size); 997 998 /* XTS mode, data_size needs to include tweak parameter */ 999 if (cipher_parms->mode == CIPHER_MODE_XTS) 1000 bd->size = cpu_to_be16(data_size + SPU_XTS_TWEAK_SIZE); 1001 else 1002 bd->size = cpu_to_be16(data_size); 1003 1004 bd->prev_length = 0; 1005 1006 packet_dump(" SPU request header: ", spu_hdr, spu_req_hdr_len); 1007 } 1008 1009 /** 1010 * spum_request_pad() - Create pad bytes at the end of the data. 1011 * @pad_start: Start of buffer where pad bytes are to be written 1012 * @gcm_ccm_padding: length of GCM/CCM padding, in bytes 1013 * @hash_pad_len: Number of bytes of padding extend data to full block 1014 * @auth_alg: authentication algorithm 1015 * @auth_mode: authentication mode 1016 * @total_sent: length inserted at end of hash pad 1017 * @status_padding: Number of bytes of padding to align STATUS word 1018 * 1019 * There may be three forms of pad: 1020 * 1. GCM/CCM pad - for GCM/CCM mode ciphers, pad to 16-byte alignment 1021 * 2. hash pad - pad to a block length, with 0x80 data terminator and 1022 * size at the end 1023 * 3. STAT pad - to ensure the STAT field is 4-byte aligned 1024 */ 1025 void spum_request_pad(u8 *pad_start, 1026 u32 gcm_ccm_padding, 1027 u32 hash_pad_len, 1028 enum hash_alg auth_alg, 1029 enum hash_mode auth_mode, 1030 unsigned int total_sent, u32 status_padding) 1031 { 1032 u8 *ptr = pad_start; 1033 1034 /* fix data alignent for GCM/CCM */ 1035 if (gcm_ccm_padding > 0) { 1036 flow_log(" GCM: padding to 16 byte alignment: %u bytes\n", 1037 gcm_ccm_padding); 1038 memset(ptr, 0, gcm_ccm_padding); 1039 ptr += gcm_ccm_padding; 1040 } 1041 1042 if (hash_pad_len > 0) { 1043 /* clear the padding section */ 1044 memset(ptr, 0, hash_pad_len); 1045 1046 if ((auth_alg == HASH_ALG_AES) && 1047 (auth_mode == HASH_MODE_XCBC)) { 1048 /* AES/XCBC just requires padding to be 0s */ 1049 ptr += hash_pad_len; 1050 } else { 1051 /* terminate the data */ 1052 *ptr = 0x80; 1053 ptr += (hash_pad_len - sizeof(u64)); 1054 1055 /* add the size at the end as required per alg */ 1056 if (auth_alg == HASH_ALG_MD5) 1057 *(__le64 *)ptr = cpu_to_le64(total_sent * 8ull); 1058 else /* SHA1, SHA2-224, SHA2-256 */ 1059 *(__be64 *)ptr = cpu_to_be64(total_sent * 8ull); 1060 ptr += sizeof(u64); 1061 } 1062 } 1063 1064 /* pad to a 4byte alignment for STAT */ 1065 if (status_padding > 0) { 1066 flow_log(" STAT: padding to 4 byte alignment: %u bytes\n", 1067 status_padding); 1068 1069 memset(ptr, 0, status_padding); 1070 ptr += status_padding; 1071 } 1072 } 1073 1074 /** 1075 * spum_xts_tweak_in_payload() - Indicate that SPUM DOES place the XTS tweak 1076 * field in the packet payload (rather than using IV) 1077 * 1078 * Return: 1 1079 */ 1080 u8 spum_xts_tweak_in_payload(void) 1081 { 1082 return 1; 1083 } 1084 1085 /** 1086 * spum_tx_status_len() - Return the length of the STATUS field in a SPU 1087 * response message. 1088 * 1089 * Return: Length of STATUS field in bytes. 1090 */ 1091 u8 spum_tx_status_len(void) 1092 { 1093 return SPU_TX_STATUS_LEN; 1094 } 1095 1096 /** 1097 * spum_rx_status_len() - Return the length of the STATUS field in a SPU 1098 * response message. 1099 * 1100 * Return: Length of STATUS field in bytes. 1101 */ 1102 u8 spum_rx_status_len(void) 1103 { 1104 return SPU_RX_STATUS_LEN; 1105 } 1106 1107 /** 1108 * spum_status_process() - Process the status from a SPU response message. 1109 * @statp: start of STATUS word 1110 * Return: 1111 * 0 - if status is good and response should be processed 1112 * !0 - status indicates an error and response is invalid 1113 */ 1114 int spum_status_process(u8 *statp) 1115 { 1116 u32 status; 1117 1118 status = __be32_to_cpu(*(__be32 *)statp); 1119 flow_log("SPU response STATUS %#08x\n", status); 1120 if (status & SPU_STATUS_ERROR_FLAG) { 1121 pr_err("%s() Warning: Error result from SPU: %#08x\n", 1122 __func__, status); 1123 if (status & SPU_STATUS_INVALID_ICV) 1124 return SPU_INVALID_ICV; 1125 return -EBADMSG; 1126 } 1127 return 0; 1128 } 1129 1130 /** 1131 * spum_ccm_update_iv() - Update the IV as per the requirements for CCM mode. 1132 * 1133 * @digestsize: Digest size of this request 1134 * @cipher_parms: (pointer to) cipher parmaeters, includes IV buf & IV len 1135 * @assoclen: Length of AAD data 1136 * @chunksize: length of input data to be sent in this req 1137 * @is_encrypt: true if this is an output/encrypt operation 1138 * @is_esp: true if this is an ESP / RFC4309 operation 1139 * 1140 */ 1141 void spum_ccm_update_iv(unsigned int digestsize, 1142 struct spu_cipher_parms *cipher_parms, 1143 unsigned int assoclen, 1144 unsigned int chunksize, 1145 bool is_encrypt, 1146 bool is_esp) 1147 { 1148 u8 L; /* L from CCM algorithm, length of plaintext data */ 1149 u8 mprime; /* M' from CCM algo, (M - 2) / 2, where M=authsize */ 1150 u8 adata; 1151 1152 if (cipher_parms->iv_len != CCM_AES_IV_SIZE) { 1153 pr_err("%s(): Invalid IV len %d for CCM mode, should be %d\n", 1154 __func__, cipher_parms->iv_len, CCM_AES_IV_SIZE); 1155 return; 1156 } 1157 1158 /* 1159 * IV needs to be formatted as follows: 1160 * 1161 * | Byte 0 | Bytes 1 - N | Bytes (N+1) - 15 | 1162 * | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | Bits 7 - 0 | Bits 7 - 0 | 1163 * | 0 |Ad?|(M - 2) / 2| L - 1 | Nonce | Plaintext Length | 1164 * 1165 * Ad? = 1 if AAD present, 0 if not present 1166 * M = size of auth field, 8, 12, or 16 bytes (SPU-M) -or- 1167 * 4, 6, 8, 10, 12, 14, 16 bytes (SPU2) 1168 * L = Size of Plaintext Length field; Nonce size = 15 - L 1169 * 1170 * It appears that the crypto API already expects the L-1 portion 1171 * to be set in the first byte of the IV, which implicitly determines 1172 * the nonce size, and also fills in the nonce. But the other bits 1173 * in byte 0 as well as the plaintext length need to be filled in. 1174 * 1175 * In rfc4309/esp mode, L is not already in the supplied IV and 1176 * we need to fill it in, as well as move the IV data to be after 1177 * the salt 1178 */ 1179 if (is_esp) { 1180 L = CCM_ESP_L_VALUE; /* RFC4309 has fixed L */ 1181 } else { 1182 /* L' = plaintext length - 1 so Plaintext length is L' + 1 */ 1183 L = ((cipher_parms->iv_buf[0] & CCM_B0_L_PRIME) >> 1184 CCM_B0_L_PRIME_SHIFT) + 1; 1185 } 1186 1187 mprime = (digestsize - 2) >> 1; /* M' = (M - 2) / 2 */ 1188 adata = (assoclen > 0); /* adata = 1 if any associated data */ 1189 1190 cipher_parms->iv_buf[0] = (adata << CCM_B0_ADATA_SHIFT) | 1191 (mprime << CCM_B0_M_PRIME_SHIFT) | 1192 ((L - 1) << CCM_B0_L_PRIME_SHIFT); 1193 1194 /* Nonce is already filled in by crypto API, and is 15 - L bytes */ 1195 1196 /* Don't include digest in plaintext size when decrypting */ 1197 if (!is_encrypt) 1198 chunksize -= digestsize; 1199 1200 /* Fill in length of plaintext, formatted to be L bytes long */ 1201 format_value_ccm(chunksize, &cipher_parms->iv_buf[15 - L + 1], L); 1202 } 1203 1204 /** 1205 * spum_wordalign_padlen() - Given the length of a data field, determine the 1206 * padding required to align the data following this field on a 4-byte boundary. 1207 * @data_size: length of data field in bytes 1208 * 1209 * Return: length of status field padding, in bytes 1210 */ 1211 u32 spum_wordalign_padlen(u32 data_size) 1212 { 1213 return ((data_size + 3) & ~3) - data_size; 1214 } 1215