1 // SPDX-License-Identifier: GPL-2.0-only 2 /** 3 * AES GCM routines supporting the Power 7+ Nest Accelerators driver 4 * 5 * Copyright (C) 2012 International Business Machines Inc. 6 * 7 * Author: Kent Yoder <yoder1@us.ibm.com> 8 */ 9 10 #include <crypto/internal/aead.h> 11 #include <crypto/aes.h> 12 #include <crypto/algapi.h> 13 #include <crypto/gcm.h> 14 #include <crypto/scatterwalk.h> 15 #include <linux/module.h> 16 #include <linux/types.h> 17 #include <asm/vio.h> 18 19 #include "nx_csbcpb.h" 20 #include "nx.h" 21 22 23 static int gcm_aes_nx_set_key(struct crypto_aead *tfm, 24 const u8 *in_key, 25 unsigned int key_len) 26 { 27 struct nx_crypto_ctx *nx_ctx = crypto_aead_ctx(tfm); 28 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb; 29 struct nx_csbcpb *csbcpb_aead = nx_ctx->csbcpb_aead; 30 31 nx_ctx_init(nx_ctx, HCOP_FC_AES); 32 33 switch (key_len) { 34 case AES_KEYSIZE_128: 35 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_128); 36 NX_CPB_SET_KEY_SIZE(csbcpb_aead, NX_KS_AES_128); 37 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_128]; 38 break; 39 case AES_KEYSIZE_192: 40 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_192); 41 NX_CPB_SET_KEY_SIZE(csbcpb_aead, NX_KS_AES_192); 42 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_192]; 43 break; 44 case AES_KEYSIZE_256: 45 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_256); 46 NX_CPB_SET_KEY_SIZE(csbcpb_aead, NX_KS_AES_256); 47 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_256]; 48 break; 49 default: 50 return -EINVAL; 51 } 52 53 csbcpb->cpb.hdr.mode = NX_MODE_AES_GCM; 54 memcpy(csbcpb->cpb.aes_gcm.key, in_key, key_len); 55 56 csbcpb_aead->cpb.hdr.mode = NX_MODE_AES_GCA; 57 memcpy(csbcpb_aead->cpb.aes_gca.key, in_key, key_len); 58 59 return 0; 60 } 61 62 static int gcm4106_aes_nx_set_key(struct crypto_aead *tfm, 63 const u8 *in_key, 64 unsigned int key_len) 65 { 66 struct nx_crypto_ctx *nx_ctx = crypto_aead_ctx(tfm); 67 char *nonce = nx_ctx->priv.gcm.nonce; 68 int rc; 69 70 if (key_len < 4) 71 return -EINVAL; 72 73 key_len -= 4; 74 75 rc = gcm_aes_nx_set_key(tfm, in_key, key_len); 76 if (rc) 77 goto out; 78 79 memcpy(nonce, in_key + key_len, 4); 80 out: 81 return rc; 82 } 83 84 static int gcm4106_aes_nx_setauthsize(struct crypto_aead *tfm, 85 unsigned int authsize) 86 { 87 switch (authsize) { 88 case 8: 89 case 12: 90 case 16: 91 break; 92 default: 93 return -EINVAL; 94 } 95 96 return 0; 97 } 98 99 static int nx_gca(struct nx_crypto_ctx *nx_ctx, 100 struct aead_request *req, 101 u8 *out, 102 unsigned int assoclen) 103 { 104 int rc; 105 struct nx_csbcpb *csbcpb_aead = nx_ctx->csbcpb_aead; 106 struct scatter_walk walk; 107 struct nx_sg *nx_sg = nx_ctx->in_sg; 108 unsigned int nbytes = assoclen; 109 unsigned int processed = 0, to_process; 110 unsigned int max_sg_len; 111 112 if (nbytes <= AES_BLOCK_SIZE) { 113 scatterwalk_start(&walk, req->src); 114 scatterwalk_copychunks(out, &walk, nbytes, SCATTERWALK_FROM_SG); 115 scatterwalk_done(&walk, SCATTERWALK_FROM_SG, 0); 116 return 0; 117 } 118 119 NX_CPB_FDM(csbcpb_aead) &= ~NX_FDM_CONTINUATION; 120 121 /* page_limit: number of sg entries that fit on one page */ 122 max_sg_len = min_t(u64, nx_driver.of.max_sg_len/sizeof(struct nx_sg), 123 nx_ctx->ap->sglen); 124 max_sg_len = min_t(u64, max_sg_len, 125 nx_ctx->ap->databytelen/NX_PAGE_SIZE); 126 127 do { 128 /* 129 * to_process: the data chunk to process in this update. 130 * This value is bound by sg list limits. 131 */ 132 to_process = min_t(u64, nbytes - processed, 133 nx_ctx->ap->databytelen); 134 to_process = min_t(u64, to_process, 135 NX_PAGE_SIZE * (max_sg_len - 1)); 136 137 nx_sg = nx_walk_and_build(nx_ctx->in_sg, max_sg_len, 138 req->src, processed, &to_process); 139 140 if ((to_process + processed) < nbytes) 141 NX_CPB_FDM(csbcpb_aead) |= NX_FDM_INTERMEDIATE; 142 else 143 NX_CPB_FDM(csbcpb_aead) &= ~NX_FDM_INTERMEDIATE; 144 145 nx_ctx->op_aead.inlen = (nx_ctx->in_sg - nx_sg) 146 * sizeof(struct nx_sg); 147 148 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op_aead, 149 req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP); 150 if (rc) 151 return rc; 152 153 memcpy(csbcpb_aead->cpb.aes_gca.in_pat, 154 csbcpb_aead->cpb.aes_gca.out_pat, 155 AES_BLOCK_SIZE); 156 NX_CPB_FDM(csbcpb_aead) |= NX_FDM_CONTINUATION; 157 158 atomic_inc(&(nx_ctx->stats->aes_ops)); 159 atomic64_add(assoclen, &(nx_ctx->stats->aes_bytes)); 160 161 processed += to_process; 162 } while (processed < nbytes); 163 164 memcpy(out, csbcpb_aead->cpb.aes_gca.out_pat, AES_BLOCK_SIZE); 165 166 return rc; 167 } 168 169 static int gmac(struct aead_request *req, const u8 *iv, unsigned int assoclen) 170 { 171 int rc; 172 struct nx_crypto_ctx *nx_ctx = 173 crypto_aead_ctx(crypto_aead_reqtfm(req)); 174 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb; 175 struct nx_sg *nx_sg; 176 unsigned int nbytes = assoclen; 177 unsigned int processed = 0, to_process; 178 unsigned int max_sg_len; 179 180 /* Set GMAC mode */ 181 csbcpb->cpb.hdr.mode = NX_MODE_AES_GMAC; 182 183 NX_CPB_FDM(csbcpb) &= ~NX_FDM_CONTINUATION; 184 185 /* page_limit: number of sg entries that fit on one page */ 186 max_sg_len = min_t(u64, nx_driver.of.max_sg_len/sizeof(struct nx_sg), 187 nx_ctx->ap->sglen); 188 max_sg_len = min_t(u64, max_sg_len, 189 nx_ctx->ap->databytelen/NX_PAGE_SIZE); 190 191 /* Copy IV */ 192 memcpy(csbcpb->cpb.aes_gcm.iv_or_cnt, iv, AES_BLOCK_SIZE); 193 194 do { 195 /* 196 * to_process: the data chunk to process in this update. 197 * This value is bound by sg list limits. 198 */ 199 to_process = min_t(u64, nbytes - processed, 200 nx_ctx->ap->databytelen); 201 to_process = min_t(u64, to_process, 202 NX_PAGE_SIZE * (max_sg_len - 1)); 203 204 nx_sg = nx_walk_and_build(nx_ctx->in_sg, max_sg_len, 205 req->src, processed, &to_process); 206 207 if ((to_process + processed) < nbytes) 208 NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE; 209 else 210 NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE; 211 212 nx_ctx->op.inlen = (nx_ctx->in_sg - nx_sg) 213 * sizeof(struct nx_sg); 214 215 csbcpb->cpb.aes_gcm.bit_length_data = 0; 216 csbcpb->cpb.aes_gcm.bit_length_aad = 8 * nbytes; 217 218 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op, 219 req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP); 220 if (rc) 221 goto out; 222 223 memcpy(csbcpb->cpb.aes_gcm.in_pat_or_aad, 224 csbcpb->cpb.aes_gcm.out_pat_or_mac, AES_BLOCK_SIZE); 225 memcpy(csbcpb->cpb.aes_gcm.in_s0, 226 csbcpb->cpb.aes_gcm.out_s0, AES_BLOCK_SIZE); 227 228 NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION; 229 230 atomic_inc(&(nx_ctx->stats->aes_ops)); 231 atomic64_add(assoclen, &(nx_ctx->stats->aes_bytes)); 232 233 processed += to_process; 234 } while (processed < nbytes); 235 236 out: 237 /* Restore GCM mode */ 238 csbcpb->cpb.hdr.mode = NX_MODE_AES_GCM; 239 return rc; 240 } 241 242 static int gcm_empty(struct aead_request *req, const u8 *iv, int enc) 243 { 244 int rc; 245 struct nx_crypto_ctx *nx_ctx = 246 crypto_aead_ctx(crypto_aead_reqtfm(req)); 247 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb; 248 char out[AES_BLOCK_SIZE]; 249 struct nx_sg *in_sg, *out_sg; 250 int len; 251 252 /* For scenarios where the input message is zero length, AES CTR mode 253 * may be used. Set the source data to be a single block (16B) of all 254 * zeros, and set the input IV value to be the same as the GMAC IV 255 * value. - nx_wb 4.8.1.3 */ 256 257 /* Change to ECB mode */ 258 csbcpb->cpb.hdr.mode = NX_MODE_AES_ECB; 259 memcpy(csbcpb->cpb.aes_ecb.key, csbcpb->cpb.aes_gcm.key, 260 sizeof(csbcpb->cpb.aes_ecb.key)); 261 if (enc) 262 NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT; 263 else 264 NX_CPB_FDM(csbcpb) &= ~NX_FDM_ENDE_ENCRYPT; 265 266 len = AES_BLOCK_SIZE; 267 268 /* Encrypt the counter/IV */ 269 in_sg = nx_build_sg_list(nx_ctx->in_sg, (u8 *) iv, 270 &len, nx_ctx->ap->sglen); 271 272 if (len != AES_BLOCK_SIZE) 273 return -EINVAL; 274 275 len = sizeof(out); 276 out_sg = nx_build_sg_list(nx_ctx->out_sg, (u8 *) out, &len, 277 nx_ctx->ap->sglen); 278 279 if (len != sizeof(out)) 280 return -EINVAL; 281 282 nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) * sizeof(struct nx_sg); 283 nx_ctx->op.outlen = (nx_ctx->out_sg - out_sg) * sizeof(struct nx_sg); 284 285 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op, 286 req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP); 287 if (rc) 288 goto out; 289 atomic_inc(&(nx_ctx->stats->aes_ops)); 290 291 /* Copy out the auth tag */ 292 memcpy(csbcpb->cpb.aes_gcm.out_pat_or_mac, out, 293 crypto_aead_authsize(crypto_aead_reqtfm(req))); 294 out: 295 /* Restore XCBC mode */ 296 csbcpb->cpb.hdr.mode = NX_MODE_AES_GCM; 297 298 /* 299 * ECB key uses the same region that GCM AAD and counter, so it's safe 300 * to just fill it with zeroes. 301 */ 302 memset(csbcpb->cpb.aes_ecb.key, 0, sizeof(csbcpb->cpb.aes_ecb.key)); 303 304 return rc; 305 } 306 307 static int gcm_aes_nx_crypt(struct aead_request *req, int enc, 308 unsigned int assoclen) 309 { 310 struct nx_crypto_ctx *nx_ctx = 311 crypto_aead_ctx(crypto_aead_reqtfm(req)); 312 struct nx_gcm_rctx *rctx = aead_request_ctx(req); 313 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb; 314 unsigned int nbytes = req->cryptlen; 315 unsigned int processed = 0, to_process; 316 unsigned long irq_flags; 317 int rc = -EINVAL; 318 319 spin_lock_irqsave(&nx_ctx->lock, irq_flags); 320 321 /* initialize the counter */ 322 *(u32 *)&rctx->iv[NX_GCM_CTR_OFFSET] = 1; 323 324 if (nbytes == 0) { 325 if (assoclen == 0) 326 rc = gcm_empty(req, rctx->iv, enc); 327 else 328 rc = gmac(req, rctx->iv, assoclen); 329 if (rc) 330 goto out; 331 else 332 goto mac; 333 } 334 335 /* Process associated data */ 336 csbcpb->cpb.aes_gcm.bit_length_aad = assoclen * 8; 337 if (assoclen) { 338 rc = nx_gca(nx_ctx, req, csbcpb->cpb.aes_gcm.in_pat_or_aad, 339 assoclen); 340 if (rc) 341 goto out; 342 } 343 344 /* Set flags for encryption */ 345 NX_CPB_FDM(csbcpb) &= ~NX_FDM_CONTINUATION; 346 if (enc) { 347 NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT; 348 } else { 349 NX_CPB_FDM(csbcpb) &= ~NX_FDM_ENDE_ENCRYPT; 350 nbytes -= crypto_aead_authsize(crypto_aead_reqtfm(req)); 351 } 352 353 do { 354 to_process = nbytes - processed; 355 356 csbcpb->cpb.aes_gcm.bit_length_data = nbytes * 8; 357 rc = nx_build_sg_lists(nx_ctx, rctx->iv, req->dst, 358 req->src, &to_process, 359 processed + req->assoclen, 360 csbcpb->cpb.aes_gcm.iv_or_cnt); 361 362 if (rc) 363 goto out; 364 365 if ((to_process + processed) < nbytes) 366 NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE; 367 else 368 NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE; 369 370 371 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op, 372 req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP); 373 if (rc) 374 goto out; 375 376 memcpy(rctx->iv, csbcpb->cpb.aes_gcm.out_cnt, AES_BLOCK_SIZE); 377 memcpy(csbcpb->cpb.aes_gcm.in_pat_or_aad, 378 csbcpb->cpb.aes_gcm.out_pat_or_mac, AES_BLOCK_SIZE); 379 memcpy(csbcpb->cpb.aes_gcm.in_s0, 380 csbcpb->cpb.aes_gcm.out_s0, AES_BLOCK_SIZE); 381 382 NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION; 383 384 atomic_inc(&(nx_ctx->stats->aes_ops)); 385 atomic64_add(csbcpb->csb.processed_byte_count, 386 &(nx_ctx->stats->aes_bytes)); 387 388 processed += to_process; 389 } while (processed < nbytes); 390 391 mac: 392 if (enc) { 393 /* copy out the auth tag */ 394 scatterwalk_map_and_copy( 395 csbcpb->cpb.aes_gcm.out_pat_or_mac, 396 req->dst, req->assoclen + nbytes, 397 crypto_aead_authsize(crypto_aead_reqtfm(req)), 398 SCATTERWALK_TO_SG); 399 } else { 400 u8 *itag = nx_ctx->priv.gcm.iauth_tag; 401 u8 *otag = csbcpb->cpb.aes_gcm.out_pat_or_mac; 402 403 scatterwalk_map_and_copy( 404 itag, req->src, req->assoclen + nbytes, 405 crypto_aead_authsize(crypto_aead_reqtfm(req)), 406 SCATTERWALK_FROM_SG); 407 rc = crypto_memneq(itag, otag, 408 crypto_aead_authsize(crypto_aead_reqtfm(req))) ? 409 -EBADMSG : 0; 410 } 411 out: 412 spin_unlock_irqrestore(&nx_ctx->lock, irq_flags); 413 return rc; 414 } 415 416 static int gcm_aes_nx_encrypt(struct aead_request *req) 417 { 418 struct nx_gcm_rctx *rctx = aead_request_ctx(req); 419 char *iv = rctx->iv; 420 421 memcpy(iv, req->iv, GCM_AES_IV_SIZE); 422 423 return gcm_aes_nx_crypt(req, 1, req->assoclen); 424 } 425 426 static int gcm_aes_nx_decrypt(struct aead_request *req) 427 { 428 struct nx_gcm_rctx *rctx = aead_request_ctx(req); 429 char *iv = rctx->iv; 430 431 memcpy(iv, req->iv, GCM_AES_IV_SIZE); 432 433 return gcm_aes_nx_crypt(req, 0, req->assoclen); 434 } 435 436 static int gcm4106_aes_nx_encrypt(struct aead_request *req) 437 { 438 struct nx_crypto_ctx *nx_ctx = 439 crypto_aead_ctx(crypto_aead_reqtfm(req)); 440 struct nx_gcm_rctx *rctx = aead_request_ctx(req); 441 char *iv = rctx->iv; 442 char *nonce = nx_ctx->priv.gcm.nonce; 443 444 memcpy(iv, nonce, NX_GCM4106_NONCE_LEN); 445 memcpy(iv + NX_GCM4106_NONCE_LEN, req->iv, 8); 446 447 if (req->assoclen < 8) 448 return -EINVAL; 449 450 return gcm_aes_nx_crypt(req, 1, req->assoclen - 8); 451 } 452 453 static int gcm4106_aes_nx_decrypt(struct aead_request *req) 454 { 455 struct nx_crypto_ctx *nx_ctx = 456 crypto_aead_ctx(crypto_aead_reqtfm(req)); 457 struct nx_gcm_rctx *rctx = aead_request_ctx(req); 458 char *iv = rctx->iv; 459 char *nonce = nx_ctx->priv.gcm.nonce; 460 461 memcpy(iv, nonce, NX_GCM4106_NONCE_LEN); 462 memcpy(iv + NX_GCM4106_NONCE_LEN, req->iv, 8); 463 464 if (req->assoclen < 8) 465 return -EINVAL; 466 467 return gcm_aes_nx_crypt(req, 0, req->assoclen - 8); 468 } 469 470 struct aead_alg nx_gcm_aes_alg = { 471 .base = { 472 .cra_name = "gcm(aes)", 473 .cra_driver_name = "gcm-aes-nx", 474 .cra_priority = 300, 475 .cra_blocksize = 1, 476 .cra_ctxsize = sizeof(struct nx_crypto_ctx), 477 .cra_module = THIS_MODULE, 478 }, 479 .init = nx_crypto_ctx_aes_gcm_init, 480 .exit = nx_crypto_ctx_aead_exit, 481 .ivsize = GCM_AES_IV_SIZE, 482 .maxauthsize = AES_BLOCK_SIZE, 483 .setkey = gcm_aes_nx_set_key, 484 .encrypt = gcm_aes_nx_encrypt, 485 .decrypt = gcm_aes_nx_decrypt, 486 }; 487 488 struct aead_alg nx_gcm4106_aes_alg = { 489 .base = { 490 .cra_name = "rfc4106(gcm(aes))", 491 .cra_driver_name = "rfc4106-gcm-aes-nx", 492 .cra_priority = 300, 493 .cra_blocksize = 1, 494 .cra_ctxsize = sizeof(struct nx_crypto_ctx), 495 .cra_module = THIS_MODULE, 496 }, 497 .init = nx_crypto_ctx_aes_gcm_init, 498 .exit = nx_crypto_ctx_aead_exit, 499 .ivsize = GCM_RFC4106_IV_SIZE, 500 .maxauthsize = AES_BLOCK_SIZE, 501 .setkey = gcm4106_aes_nx_set_key, 502 .setauthsize = gcm4106_aes_nx_setauthsize, 503 .encrypt = gcm4106_aes_nx_encrypt, 504 .decrypt = gcm4106_aes_nx_decrypt, 505 }; 506