1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * sun8i-ss-cipher.c - hardware cryptographic offloader for 4 * Allwinner A80/A83T SoC 5 * 6 * Copyright (C) 2016-2019 Corentin LABBE <clabbe.montjoie@gmail.com> 7 * 8 * This file add support for AES cipher with 128,192,256 bits keysize in 9 * CBC and ECB mode. 10 * 11 * You could find a link for the datasheet in Documentation/arch/arm/sunxi.rst 12 */ 13 14 #include <linux/bottom_half.h> 15 #include <linux/crypto.h> 16 #include <linux/dma-mapping.h> 17 #include <linux/io.h> 18 #include <linux/pm_runtime.h> 19 #include <crypto/scatterwalk.h> 20 #include <crypto/internal/skcipher.h> 21 #include "sun8i-ss.h" 22 23 static bool sun8i_ss_need_fallback(struct skcipher_request *areq) 24 { 25 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq); 26 struct skcipher_alg *alg = crypto_skcipher_alg(tfm); 27 struct sun8i_ss_alg_template *algt = container_of(alg, struct sun8i_ss_alg_template, alg.skcipher.base); 28 struct scatterlist *in_sg = areq->src; 29 struct scatterlist *out_sg = areq->dst; 30 struct scatterlist *sg; 31 unsigned int todo, len; 32 33 if (areq->cryptlen == 0 || areq->cryptlen % 16) { 34 algt->stat_fb_len++; 35 return true; 36 } 37 38 if (sg_nents_for_len(areq->src, areq->cryptlen) > 8 || 39 sg_nents_for_len(areq->dst, areq->cryptlen) > 8) { 40 algt->stat_fb_sgnum++; 41 return true; 42 } 43 44 len = areq->cryptlen; 45 sg = areq->src; 46 while (sg) { 47 todo = min(len, sg->length); 48 if ((todo % 16) != 0) { 49 algt->stat_fb_sglen++; 50 return true; 51 } 52 if (!IS_ALIGNED(sg->offset, 16)) { 53 algt->stat_fb_align++; 54 return true; 55 } 56 len -= todo; 57 sg = sg_next(sg); 58 } 59 len = areq->cryptlen; 60 sg = areq->dst; 61 while (sg) { 62 todo = min(len, sg->length); 63 if ((todo % 16) != 0) { 64 algt->stat_fb_sglen++; 65 return true; 66 } 67 if (!IS_ALIGNED(sg->offset, 16)) { 68 algt->stat_fb_align++; 69 return true; 70 } 71 len -= todo; 72 sg = sg_next(sg); 73 } 74 75 /* SS need same numbers of SG (with same length) for source and destination */ 76 in_sg = areq->src; 77 out_sg = areq->dst; 78 while (in_sg && out_sg) { 79 if (in_sg->length != out_sg->length) 80 return true; 81 in_sg = sg_next(in_sg); 82 out_sg = sg_next(out_sg); 83 } 84 if (in_sg || out_sg) 85 return true; 86 return false; 87 } 88 89 static int sun8i_ss_cipher_fallback(struct skcipher_request *areq) 90 { 91 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq); 92 struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm); 93 struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq); 94 int err; 95 96 if (IS_ENABLED(CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG)) { 97 struct skcipher_alg *alg = crypto_skcipher_alg(tfm); 98 struct sun8i_ss_alg_template *algt __maybe_unused; 99 100 algt = container_of(alg, struct sun8i_ss_alg_template, 101 alg.skcipher.base); 102 103 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG 104 algt->stat_fb++; 105 #endif 106 } 107 108 skcipher_request_set_tfm(&rctx->fallback_req, op->fallback_tfm); 109 skcipher_request_set_callback(&rctx->fallback_req, areq->base.flags, 110 areq->base.complete, areq->base.data); 111 skcipher_request_set_crypt(&rctx->fallback_req, areq->src, areq->dst, 112 areq->cryptlen, areq->iv); 113 if (rctx->op_dir & SS_DECRYPTION) 114 err = crypto_skcipher_decrypt(&rctx->fallback_req); 115 else 116 err = crypto_skcipher_encrypt(&rctx->fallback_req); 117 return err; 118 } 119 120 static int sun8i_ss_setup_ivs(struct skcipher_request *areq) 121 { 122 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq); 123 struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm); 124 struct sun8i_ss_dev *ss = op->ss; 125 struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq); 126 struct scatterlist *sg = areq->src; 127 unsigned int todo, offset; 128 unsigned int len = areq->cryptlen; 129 unsigned int ivsize = crypto_skcipher_ivsize(tfm); 130 struct sun8i_ss_flow *sf = &ss->flows[rctx->flow]; 131 int i = 0; 132 dma_addr_t a; 133 int err; 134 135 rctx->ivlen = ivsize; 136 if (rctx->op_dir & SS_DECRYPTION) { 137 offset = areq->cryptlen - ivsize; 138 scatterwalk_map_and_copy(sf->biv, areq->src, offset, 139 ivsize, 0); 140 } 141 142 /* we need to copy all IVs from source in case DMA is bi-directionnal */ 143 while (sg && len) { 144 if (sg_dma_len(sg) == 0) { 145 sg = sg_next(sg); 146 continue; 147 } 148 if (i == 0) 149 memcpy(sf->iv[0], areq->iv, ivsize); 150 a = dma_map_single(ss->dev, sf->iv[i], ivsize, DMA_TO_DEVICE); 151 if (dma_mapping_error(ss->dev, a)) { 152 memzero_explicit(sf->iv[i], ivsize); 153 dev_err(ss->dev, "Cannot DMA MAP IV\n"); 154 err = -EFAULT; 155 goto dma_iv_error; 156 } 157 rctx->p_iv[i] = a; 158 /* we need to setup all others IVs only in the decrypt way */ 159 if (rctx->op_dir == SS_ENCRYPTION) 160 return 0; 161 todo = min(len, sg_dma_len(sg)); 162 len -= todo; 163 i++; 164 if (i < MAX_SG) { 165 offset = sg->length - ivsize; 166 scatterwalk_map_and_copy(sf->iv[i], sg, offset, ivsize, 0); 167 } 168 rctx->niv = i; 169 sg = sg_next(sg); 170 } 171 172 return 0; 173 dma_iv_error: 174 i--; 175 while (i >= 0) { 176 dma_unmap_single(ss->dev, rctx->p_iv[i], ivsize, DMA_TO_DEVICE); 177 memzero_explicit(sf->iv[i], ivsize); 178 i--; 179 } 180 return err; 181 } 182 183 static int sun8i_ss_cipher(struct skcipher_request *areq) 184 { 185 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq); 186 struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm); 187 struct sun8i_ss_dev *ss = op->ss; 188 struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq); 189 struct skcipher_alg *alg = crypto_skcipher_alg(tfm); 190 struct sun8i_ss_alg_template *algt; 191 struct sun8i_ss_flow *sf = &ss->flows[rctx->flow]; 192 struct scatterlist *sg; 193 unsigned int todo, len, offset, ivsize; 194 int nr_sgs = 0; 195 int nr_sgd = 0; 196 int err = 0; 197 int nsgs = sg_nents_for_len(areq->src, areq->cryptlen); 198 int nsgd = sg_nents_for_len(areq->dst, areq->cryptlen); 199 int i; 200 201 algt = container_of(alg, struct sun8i_ss_alg_template, alg.skcipher.base); 202 203 dev_dbg(ss->dev, "%s %s %u %x IV(%p %u) key=%u\n", __func__, 204 crypto_tfm_alg_name(areq->base.tfm), 205 areq->cryptlen, 206 rctx->op_dir, areq->iv, crypto_skcipher_ivsize(tfm), 207 op->keylen); 208 209 #ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG 210 algt->stat_req++; 211 #endif 212 213 rctx->op_mode = ss->variant->op_mode[algt->ss_blockmode]; 214 rctx->method = ss->variant->alg_cipher[algt->ss_algo_id]; 215 rctx->keylen = op->keylen; 216 217 rctx->p_key = dma_map_single(ss->dev, op->key, op->keylen, DMA_TO_DEVICE); 218 if (dma_mapping_error(ss->dev, rctx->p_key)) { 219 dev_err(ss->dev, "Cannot DMA MAP KEY\n"); 220 err = -EFAULT; 221 goto theend; 222 } 223 224 ivsize = crypto_skcipher_ivsize(tfm); 225 if (areq->iv && crypto_skcipher_ivsize(tfm) > 0) { 226 err = sun8i_ss_setup_ivs(areq); 227 if (err) 228 goto theend_key; 229 } 230 if (areq->src == areq->dst) { 231 nr_sgs = dma_map_sg(ss->dev, areq->src, nsgs, DMA_BIDIRECTIONAL); 232 if (nr_sgs <= 0 || nr_sgs > 8) { 233 dev_err(ss->dev, "Invalid sg number %d\n", nr_sgs); 234 err = -EINVAL; 235 goto theend_iv; 236 } 237 nr_sgd = nr_sgs; 238 } else { 239 nr_sgs = dma_map_sg(ss->dev, areq->src, nsgs, DMA_TO_DEVICE); 240 if (nr_sgs <= 0 || nr_sgs > 8) { 241 dev_err(ss->dev, "Invalid sg number %d\n", nr_sgs); 242 err = -EINVAL; 243 goto theend_iv; 244 } 245 nr_sgd = dma_map_sg(ss->dev, areq->dst, nsgd, DMA_FROM_DEVICE); 246 if (nr_sgd <= 0 || nr_sgd > 8) { 247 dev_err(ss->dev, "Invalid sg number %d\n", nr_sgd); 248 err = -EINVAL; 249 goto theend_sgs; 250 } 251 } 252 253 len = areq->cryptlen; 254 i = 0; 255 sg = areq->src; 256 while (i < nr_sgs && sg && len) { 257 if (sg_dma_len(sg) == 0) 258 goto sgs_next; 259 rctx->t_src[i].addr = sg_dma_address(sg); 260 todo = min(len, sg_dma_len(sg)); 261 rctx->t_src[i].len = todo / 4; 262 dev_dbg(ss->dev, "%s total=%u SGS(%d %u off=%d) todo=%u\n", __func__, 263 areq->cryptlen, i, rctx->t_src[i].len, sg->offset, todo); 264 len -= todo; 265 i++; 266 sgs_next: 267 sg = sg_next(sg); 268 } 269 if (len > 0) { 270 dev_err(ss->dev, "remaining len %d\n", len); 271 err = -EINVAL; 272 goto theend_sgs; 273 } 274 275 len = areq->cryptlen; 276 i = 0; 277 sg = areq->dst; 278 while (i < nr_sgd && sg && len) { 279 if (sg_dma_len(sg) == 0) 280 goto sgd_next; 281 rctx->t_dst[i].addr = sg_dma_address(sg); 282 todo = min(len, sg_dma_len(sg)); 283 rctx->t_dst[i].len = todo / 4; 284 dev_dbg(ss->dev, "%s total=%u SGD(%d %u off=%d) todo=%u\n", __func__, 285 areq->cryptlen, i, rctx->t_dst[i].len, sg->offset, todo); 286 len -= todo; 287 i++; 288 sgd_next: 289 sg = sg_next(sg); 290 } 291 if (len > 0) { 292 dev_err(ss->dev, "remaining len %d\n", len); 293 err = -EINVAL; 294 goto theend_sgs; 295 } 296 297 err = sun8i_ss_run_task(ss, rctx, crypto_tfm_alg_name(areq->base.tfm)); 298 299 theend_sgs: 300 if (areq->src == areq->dst) { 301 dma_unmap_sg(ss->dev, areq->src, nsgs, DMA_BIDIRECTIONAL); 302 } else { 303 dma_unmap_sg(ss->dev, areq->src, nsgs, DMA_TO_DEVICE); 304 dma_unmap_sg(ss->dev, areq->dst, nsgd, DMA_FROM_DEVICE); 305 } 306 307 theend_iv: 308 if (areq->iv && ivsize > 0) { 309 for (i = 0; i < rctx->niv; i++) { 310 dma_unmap_single(ss->dev, rctx->p_iv[i], ivsize, DMA_TO_DEVICE); 311 memzero_explicit(sf->iv[i], ivsize); 312 } 313 314 offset = areq->cryptlen - ivsize; 315 if (rctx->op_dir & SS_DECRYPTION) { 316 memcpy(areq->iv, sf->biv, ivsize); 317 memzero_explicit(sf->biv, ivsize); 318 } else { 319 scatterwalk_map_and_copy(areq->iv, areq->dst, offset, 320 ivsize, 0); 321 } 322 } 323 324 theend_key: 325 dma_unmap_single(ss->dev, rctx->p_key, op->keylen, DMA_TO_DEVICE); 326 327 theend: 328 329 return err; 330 } 331 332 int sun8i_ss_handle_cipher_request(struct crypto_engine *engine, void *areq) 333 { 334 int err; 335 struct skcipher_request *breq = container_of(areq, struct skcipher_request, base); 336 337 err = sun8i_ss_cipher(breq); 338 local_bh_disable(); 339 crypto_finalize_skcipher_request(engine, breq, err); 340 local_bh_enable(); 341 342 return 0; 343 } 344 345 int sun8i_ss_skdecrypt(struct skcipher_request *areq) 346 { 347 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq); 348 struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm); 349 struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq); 350 struct crypto_engine *engine; 351 int e; 352 353 memset(rctx, 0, sizeof(struct sun8i_cipher_req_ctx)); 354 rctx->op_dir = SS_DECRYPTION; 355 356 if (sun8i_ss_need_fallback(areq)) 357 return sun8i_ss_cipher_fallback(areq); 358 359 e = sun8i_ss_get_engine_number(op->ss); 360 engine = op->ss->flows[e].engine; 361 rctx->flow = e; 362 363 return crypto_transfer_skcipher_request_to_engine(engine, areq); 364 } 365 366 int sun8i_ss_skencrypt(struct skcipher_request *areq) 367 { 368 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq); 369 struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm); 370 struct sun8i_cipher_req_ctx *rctx = skcipher_request_ctx(areq); 371 struct crypto_engine *engine; 372 int e; 373 374 memset(rctx, 0, sizeof(struct sun8i_cipher_req_ctx)); 375 rctx->op_dir = SS_ENCRYPTION; 376 377 if (sun8i_ss_need_fallback(areq)) 378 return sun8i_ss_cipher_fallback(areq); 379 380 e = sun8i_ss_get_engine_number(op->ss); 381 engine = op->ss->flows[e].engine; 382 rctx->flow = e; 383 384 return crypto_transfer_skcipher_request_to_engine(engine, areq); 385 } 386 387 int sun8i_ss_cipher_init(struct crypto_tfm *tfm) 388 { 389 struct sun8i_cipher_tfm_ctx *op = crypto_tfm_ctx(tfm); 390 struct sun8i_ss_alg_template *algt; 391 const char *name = crypto_tfm_alg_name(tfm); 392 struct crypto_skcipher *sktfm = __crypto_skcipher_cast(tfm); 393 struct skcipher_alg *alg = crypto_skcipher_alg(sktfm); 394 int err; 395 396 memset(op, 0, sizeof(struct sun8i_cipher_tfm_ctx)); 397 398 algt = container_of(alg, struct sun8i_ss_alg_template, alg.skcipher.base); 399 op->ss = algt->ss; 400 401 op->fallback_tfm = crypto_alloc_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK); 402 if (IS_ERR(op->fallback_tfm)) { 403 dev_err(op->ss->dev, "ERROR: Cannot allocate fallback for %s %ld\n", 404 name, PTR_ERR(op->fallback_tfm)); 405 return PTR_ERR(op->fallback_tfm); 406 } 407 408 crypto_skcipher_set_reqsize(sktfm, sizeof(struct sun8i_cipher_req_ctx) + 409 crypto_skcipher_reqsize(op->fallback_tfm)); 410 411 memcpy(algt->fbname, 412 crypto_tfm_alg_driver_name(crypto_skcipher_tfm(op->fallback_tfm)), 413 CRYPTO_MAX_ALG_NAME); 414 415 err = pm_runtime_resume_and_get(op->ss->dev); 416 if (err < 0) { 417 dev_err(op->ss->dev, "pm error %d\n", err); 418 goto error_pm; 419 } 420 421 return 0; 422 error_pm: 423 crypto_free_skcipher(op->fallback_tfm); 424 return err; 425 } 426 427 void sun8i_ss_cipher_exit(struct crypto_tfm *tfm) 428 { 429 struct sun8i_cipher_tfm_ctx *op = crypto_tfm_ctx(tfm); 430 431 kfree_sensitive(op->key); 432 crypto_free_skcipher(op->fallback_tfm); 433 pm_runtime_put_sync(op->ss->dev); 434 } 435 436 int sun8i_ss_aes_setkey(struct crypto_skcipher *tfm, const u8 *key, 437 unsigned int keylen) 438 { 439 struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm); 440 struct sun8i_ss_dev *ss = op->ss; 441 442 switch (keylen) { 443 case 128 / 8: 444 break; 445 case 192 / 8: 446 break; 447 case 256 / 8: 448 break; 449 default: 450 dev_dbg(ss->dev, "ERROR: Invalid keylen %u\n", keylen); 451 return -EINVAL; 452 } 453 kfree_sensitive(op->key); 454 op->keylen = keylen; 455 op->key = kmemdup(key, keylen, GFP_KERNEL); 456 if (!op->key) 457 return -ENOMEM; 458 459 crypto_skcipher_clear_flags(op->fallback_tfm, CRYPTO_TFM_REQ_MASK); 460 crypto_skcipher_set_flags(op->fallback_tfm, tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK); 461 462 return crypto_skcipher_setkey(op->fallback_tfm, key, keylen); 463 } 464 465 int sun8i_ss_des3_setkey(struct crypto_skcipher *tfm, const u8 *key, 466 unsigned int keylen) 467 { 468 struct sun8i_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm); 469 struct sun8i_ss_dev *ss = op->ss; 470 471 if (unlikely(keylen != 3 * DES_KEY_SIZE)) { 472 dev_dbg(ss->dev, "Invalid keylen %u\n", keylen); 473 return -EINVAL; 474 } 475 476 kfree_sensitive(op->key); 477 op->keylen = keylen; 478 op->key = kmemdup(key, keylen, GFP_KERNEL); 479 if (!op->key) 480 return -ENOMEM; 481 482 crypto_skcipher_clear_flags(op->fallback_tfm, CRYPTO_TFM_REQ_MASK); 483 crypto_skcipher_set_flags(op->fallback_tfm, tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK); 484 485 return crypto_skcipher_setkey(op->fallback_tfm, key, keylen); 486 } 487