1// SPDX-License-Identifier: GPL-2.0 2/* 3 * sl3516-ce-cipher.c - hardware cryptographic offloader for Storlink SL3516 SoC 4 * 5 * Copyright (C) 2021 Corentin LABBE <clabbe@baylibre.com> 6 * 7 * This file adds support for AES cipher with 128,192,256 bits keysize in 8 * ECB mode. 9 */ 10 11#include <crypto/engine.h> 12#include <crypto/internal/skcipher.h> 13#include <crypto/scatterwalk.h> 14#include <linux/dma-mapping.h> 15#include <linux/delay.h> 16#include <linux/err.h> 17#include <linux/io.h> 18#include <linux/kernel.h> 19#include <linux/pm_runtime.h> 20#include <linux/slab.h> 21#include <linux/string.h> 22#include "sl3516-ce.h" 23 24/* sl3516_ce_need_fallback - check if a request can be handled by the CE */ 25static bool sl3516_ce_need_fallback(struct skcipher_request *areq) 26{ 27 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq); 28 struct sl3516_ce_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm); 29 struct sl3516_ce_dev *ce = op->ce; 30 struct scatterlist *in_sg; 31 struct scatterlist *out_sg; 32 struct scatterlist *sg; 33 34 if (areq->cryptlen == 0 || areq->cryptlen % 16) { 35 ce->fallback_mod16++; 36 return true; 37 } 38 39 /* 40 * check if we have enough descriptors for TX 41 * Note: TX need one control desc for each SG 42 */ 43 if (sg_nents(areq->src) > MAXDESC / 2) { 44 ce->fallback_sg_count_tx++; 45 return true; 46 } 47 /* check if we have enough descriptors for RX */ 48 if (sg_nents(areq->dst) > MAXDESC) { 49 ce->fallback_sg_count_rx++; 50 return true; 51 } 52 53 sg = areq->src; 54 while (sg) { 55 if ((sg->length % 16) != 0) { 56 ce->fallback_mod16++; 57 return true; 58 } 59 if ((sg_dma_len(sg) % 16) != 0) { 60 ce->fallback_mod16++; 61 return true; 62 } 63 if (!IS_ALIGNED(sg->offset, 16)) { 64 ce->fallback_align16++; 65 return true; 66 } 67 sg = sg_next(sg); 68 } 69 sg = areq->dst; 70 while (sg) { 71 if ((sg->length % 16) != 0) { 72 ce->fallback_mod16++; 73 return true; 74 } 75 if ((sg_dma_len(sg) % 16) != 0) { 76 ce->fallback_mod16++; 77 return true; 78 } 79 if (!IS_ALIGNED(sg->offset, 16)) { 80 ce->fallback_align16++; 81 return true; 82 } 83 sg = sg_next(sg); 84 } 85 86 /* need same numbers of SG (with same length) for source and destination */ 87 in_sg = areq->src; 88 out_sg = areq->dst; 89 while (in_sg && out_sg) { 90 if (in_sg->length != out_sg->length) { 91 ce->fallback_not_same_len++; 92 return true; 93 } 94 in_sg = sg_next(in_sg); 95 out_sg = sg_next(out_sg); 96 } 97 if (in_sg || out_sg) 98 return true; 99 100 return false; 101} 102 103static int sl3516_ce_cipher_fallback(struct skcipher_request *areq) 104{ 105 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq); 106 struct sl3516_ce_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm); 107 struct sl3516_ce_cipher_req_ctx *rctx = skcipher_request_ctx(areq); 108 struct skcipher_alg *alg = crypto_skcipher_alg(tfm); 109 struct sl3516_ce_alg_template *algt; 110 int err; 111 112 algt = container_of(alg, struct sl3516_ce_alg_template, alg.skcipher.base); 113 algt->stat_fb++; 114 115 skcipher_request_set_tfm(&rctx->fallback_req, op->fallback_tfm); 116 skcipher_request_set_callback(&rctx->fallback_req, areq->base.flags, 117 areq->base.complete, areq->base.data); 118 skcipher_request_set_crypt(&rctx->fallback_req, areq->src, areq->dst, 119 areq->cryptlen, areq->iv); 120 if (rctx->op_dir == CE_DECRYPTION) 121 err = crypto_skcipher_decrypt(&rctx->fallback_req); 122 else 123 err = crypto_skcipher_encrypt(&rctx->fallback_req); 124 return err; 125} 126 127static int sl3516_ce_cipher(struct skcipher_request *areq) 128{ 129 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq); 130 struct sl3516_ce_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm); 131 struct sl3516_ce_dev *ce = op->ce; 132 struct sl3516_ce_cipher_req_ctx *rctx = skcipher_request_ctx(areq); 133 struct skcipher_alg *alg = crypto_skcipher_alg(tfm); 134 struct sl3516_ce_alg_template *algt; 135 struct scatterlist *sg; 136 unsigned int todo, len; 137 struct pkt_control_ecb *ecb; 138 int nr_sgs = 0; 139 int nr_sgd = 0; 140 int err = 0; 141 int i; 142 143 algt = container_of(alg, struct sl3516_ce_alg_template, alg.skcipher.base); 144 145 dev_dbg(ce->dev, "%s %s %u %x IV(%p %u) key=%u\n", __func__, 146 crypto_tfm_alg_name(areq->base.tfm), 147 areq->cryptlen, 148 rctx->op_dir, areq->iv, crypto_skcipher_ivsize(tfm), 149 op->keylen); 150 151 algt->stat_req++; 152 153 if (areq->src == areq->dst) { 154 nr_sgs = dma_map_sg(ce->dev, areq->src, sg_nents(areq->src), 155 DMA_BIDIRECTIONAL); 156 if (nr_sgs <= 0 || nr_sgs > MAXDESC / 2) { 157 dev_err(ce->dev, "Invalid sg number %d\n", nr_sgs); 158 err = -EINVAL; 159 goto theend; 160 } 161 nr_sgd = nr_sgs; 162 } else { 163 nr_sgs = dma_map_sg(ce->dev, areq->src, sg_nents(areq->src), 164 DMA_TO_DEVICE); 165 if (nr_sgs <= 0 || nr_sgs > MAXDESC / 2) { 166 dev_err(ce->dev, "Invalid sg number %d\n", nr_sgs); 167 err = -EINVAL; 168 goto theend; 169 } 170 nr_sgd = dma_map_sg(ce->dev, areq->dst, sg_nents(areq->dst), 171 DMA_FROM_DEVICE); 172 if (nr_sgd <= 0 || nr_sgd > MAXDESC) { 173 dev_err(ce->dev, "Invalid sg number %d\n", nr_sgd); 174 err = -EINVAL; 175 goto theend_sgs; 176 } 177 } 178 179 len = areq->cryptlen; 180 i = 0; 181 sg = areq->src; 182 while (i < nr_sgs && sg && len) { 183 if (sg_dma_len(sg) == 0) 184 goto sgs_next; 185 rctx->t_src[i].addr = sg_dma_address(sg); 186 todo = min(len, sg_dma_len(sg)); 187 rctx->t_src[i].len = todo; 188 dev_dbg(ce->dev, "%s total=%u SGS(%d %u off=%d) todo=%u\n", __func__, 189 areq->cryptlen, i, rctx->t_src[i].len, sg->offset, todo); 190 len -= todo; 191 i++; 192sgs_next: 193 sg = sg_next(sg); 194 } 195 if (len > 0) { 196 dev_err(ce->dev, "remaining len %d/%u nr_sgs=%d\n", len, areq->cryptlen, nr_sgs); 197 err = -EINVAL; 198 goto theend_sgs; 199 } 200 201 len = areq->cryptlen; 202 i = 0; 203 sg = areq->dst; 204 while (i < nr_sgd && sg && len) { 205 if (sg_dma_len(sg) == 0) 206 goto sgd_next; 207 rctx->t_dst[i].addr = sg_dma_address(sg); 208 todo = min(len, sg_dma_len(sg)); 209 rctx->t_dst[i].len = todo; 210 dev_dbg(ce->dev, "%s total=%u SGD(%d %u off=%d) todo=%u\n", __func__, 211 areq->cryptlen, i, rctx->t_dst[i].len, sg->offset, todo); 212 len -= todo; 213 i++; 214 215sgd_next: 216 sg = sg_next(sg); 217 } 218 if (len > 0) { 219 dev_err(ce->dev, "remaining len %d\n", len); 220 err = -EINVAL; 221 goto theend_sgs; 222 } 223 224 switch (algt->mode) { 225 case ECB_AES: 226 rctx->pctrllen = sizeof(struct pkt_control_ecb); 227 ecb = (struct pkt_control_ecb *)ce->pctrl; 228 229 rctx->tqflag = TQ0_TYPE_CTRL; 230 rctx->tqflag |= TQ1_CIPHER; 231 ecb->control.op_mode = rctx->op_dir; 232 ecb->control.cipher_algorithm = ECB_AES; 233 ecb->cipher.header_len = 0; 234 ecb->cipher.algorithm_len = areq->cryptlen; 235 cpu_to_be32_array((__be32 *)ecb->key, (u32 *)op->key, op->keylen / 4); 236 rctx->h = &ecb->cipher; 237 238 rctx->tqflag |= TQ4_KEY0; 239 rctx->tqflag |= TQ5_KEY4; 240 rctx->tqflag |= TQ6_KEY6; 241 ecb->control.aesnk = op->keylen / 4; 242 break; 243 } 244 245 rctx->nr_sgs = nr_sgs; 246 rctx->nr_sgd = nr_sgd; 247 err = sl3516_ce_run_task(ce, rctx, crypto_tfm_alg_name(areq->base.tfm)); 248 249theend_sgs: 250 if (areq->src == areq->dst) { 251 dma_unmap_sg(ce->dev, areq->src, sg_nents(areq->src), 252 DMA_BIDIRECTIONAL); 253 } else { 254 dma_unmap_sg(ce->dev, areq->src, sg_nents(areq->src), 255 DMA_TO_DEVICE); 256 dma_unmap_sg(ce->dev, areq->dst, sg_nents(areq->dst), 257 DMA_FROM_DEVICE); 258 } 259 260theend: 261 262 return err; 263} 264 265int sl3516_ce_handle_cipher_request(struct crypto_engine *engine, void *areq) 266{ 267 int err; 268 struct skcipher_request *breq = container_of(areq, struct skcipher_request, base); 269 270 err = sl3516_ce_cipher(breq); 271 local_bh_disable(); 272 crypto_finalize_skcipher_request(engine, breq, err); 273 local_bh_enable(); 274 275 return 0; 276} 277 278int sl3516_ce_skdecrypt(struct skcipher_request *areq) 279{ 280 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq); 281 struct sl3516_ce_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm); 282 struct sl3516_ce_cipher_req_ctx *rctx = skcipher_request_ctx(areq); 283 struct crypto_engine *engine; 284 285 memset(rctx, 0, sizeof(struct sl3516_ce_cipher_req_ctx)); 286 rctx->op_dir = CE_DECRYPTION; 287 288 if (sl3516_ce_need_fallback(areq)) 289 return sl3516_ce_cipher_fallback(areq); 290 291 engine = op->ce->engine; 292 293 return crypto_transfer_skcipher_request_to_engine(engine, areq); 294} 295 296int sl3516_ce_skencrypt(struct skcipher_request *areq) 297{ 298 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq); 299 struct sl3516_ce_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm); 300 struct sl3516_ce_cipher_req_ctx *rctx = skcipher_request_ctx(areq); 301 struct crypto_engine *engine; 302 303 memset(rctx, 0, sizeof(struct sl3516_ce_cipher_req_ctx)); 304 rctx->op_dir = CE_ENCRYPTION; 305 306 if (sl3516_ce_need_fallback(areq)) 307 return sl3516_ce_cipher_fallback(areq); 308 309 engine = op->ce->engine; 310 311 return crypto_transfer_skcipher_request_to_engine(engine, areq); 312} 313 314int sl3516_ce_cipher_init(struct crypto_tfm *tfm) 315{ 316 struct sl3516_ce_cipher_tfm_ctx *op = crypto_tfm_ctx(tfm); 317 struct sl3516_ce_alg_template *algt; 318 const char *name = crypto_tfm_alg_name(tfm); 319 struct crypto_skcipher *sktfm = __crypto_skcipher_cast(tfm); 320 struct skcipher_alg *alg = crypto_skcipher_alg(sktfm); 321 int err; 322 323 memset(op, 0, sizeof(struct sl3516_ce_cipher_tfm_ctx)); 324 325 algt = container_of(alg, struct sl3516_ce_alg_template, alg.skcipher.base); 326 op->ce = algt->ce; 327 328 op->fallback_tfm = crypto_alloc_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK); 329 if (IS_ERR(op->fallback_tfm)) { 330 dev_err(op->ce->dev, "ERROR: Cannot allocate fallback for %s %ld\n", 331 name, PTR_ERR(op->fallback_tfm)); 332 return PTR_ERR(op->fallback_tfm); 333 } 334 335 crypto_skcipher_set_reqsize(sktfm, sizeof(struct sl3516_ce_cipher_req_ctx) + 336 crypto_skcipher_reqsize(op->fallback_tfm)); 337 338 dev_info(op->ce->dev, "Fallback for %s is %s\n", 339 crypto_tfm_alg_driver_name(&sktfm->base), 340 crypto_tfm_alg_driver_name(crypto_skcipher_tfm(op->fallback_tfm))); 341 342 err = pm_runtime_get_sync(op->ce->dev); 343 if (err < 0) 344 goto error_pm; 345 346 return 0; 347error_pm: 348 pm_runtime_put_noidle(op->ce->dev); 349 crypto_free_skcipher(op->fallback_tfm); 350 return err; 351} 352 353void sl3516_ce_cipher_exit(struct crypto_tfm *tfm) 354{ 355 struct sl3516_ce_cipher_tfm_ctx *op = crypto_tfm_ctx(tfm); 356 357 kfree_sensitive(op->key); 358 crypto_free_skcipher(op->fallback_tfm); 359 pm_runtime_put_sync_suspend(op->ce->dev); 360} 361 362int sl3516_ce_aes_setkey(struct crypto_skcipher *tfm, const u8 *key, 363 unsigned int keylen) 364{ 365 struct sl3516_ce_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm); 366 struct sl3516_ce_dev *ce = op->ce; 367 368 switch (keylen) { 369 case 128 / 8: 370 break; 371 case 192 / 8: 372 break; 373 case 256 / 8: 374 break; 375 default: 376 dev_dbg(ce->dev, "ERROR: Invalid keylen %u\n", keylen); 377 return -EINVAL; 378 } 379 kfree_sensitive(op->key); 380 op->keylen = keylen; 381 op->key = kmemdup(key, keylen, GFP_KERNEL | GFP_DMA); 382 if (!op->key) 383 return -ENOMEM; 384 385 crypto_skcipher_clear_flags(op->fallback_tfm, CRYPTO_TFM_REQ_MASK); 386 crypto_skcipher_set_flags(op->fallback_tfm, tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK); 387 388 return crypto_skcipher_setkey(op->fallback_tfm, key, keylen); 389} 390