| // SPDX-License-Identifier: GPL-2.0 | |
| /* | |
| * sl3516-ce-cipher.c - hardware cryptographic offloader for Storlink SL3516 SoC | |
| * | |
| * Copyright (C) 2021 Corentin LABBE <clabbe@baylibre.com> | |
| * | |
| * This file adds support for AES cipher with 128,192,256 bits keysize in | |
| * ECB mode. | |
| */ | |
| #include <crypto/engine.h> | |
| #include <crypto/internal/skcipher.h> | |
| #include <crypto/scatterwalk.h> | |
| #include <linux/dma-mapping.h> | |
| #include <linux/delay.h> | |
| #include <linux/err.h> | |
| #include <linux/io.h> | |
| #include <linux/kernel.h> | |
| #include <linux/pm_runtime.h> | |
| #include <linux/slab.h> | |
| #include <linux/string.h> | |
| #include "sl3516-ce.h" | |
| /* sl3516_ce_need_fallback - check if a request can be handled by the CE */ | |
| static bool sl3516_ce_need_fallback(struct skcipher_request *areq) | |
| { | |
| struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq); | |
| struct sl3516_ce_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm); | |
| struct sl3516_ce_dev *ce = op->ce; | |
| struct scatterlist *in_sg; | |
| struct scatterlist *out_sg; | |
| struct scatterlist *sg; | |
| if (areq->cryptlen == 0 || areq->cryptlen % 16) { | |
| ce->fallback_mod16++; | |
| return true; | |
| } | |
| /* | |
| * check if we have enough descriptors for TX | |
| * Note: TX need one control desc for each SG | |
| */ | |
| if (sg_nents(areq->src) > MAXDESC / 2) { | |
| ce->fallback_sg_count_tx++; | |
| return true; | |
| } | |
| /* check if we have enough descriptors for RX */ | |
| if (sg_nents(areq->dst) > MAXDESC) { | |
| ce->fallback_sg_count_rx++; | |
| return true; | |
| } | |
| sg = areq->src; | |
| while (sg) { | |
| if ((sg->length % 16) != 0) { | |
| ce->fallback_mod16++; | |
| return true; | |
| } | |
| if (!IS_ALIGNED(sg->offset, 16)) { | |
| ce->fallback_align16++; | |
| return true; | |
| } | |
| sg = sg_next(sg); | |
| } | |
| sg = areq->dst; | |
| while (sg) { | |
| if ((sg->length % 16) != 0) { | |
| ce->fallback_mod16++; | |
| return true; | |
| } | |
| if (!IS_ALIGNED(sg->offset, 16)) { | |
| ce->fallback_align16++; | |
| return true; | |
| } | |
| sg = sg_next(sg); | |
| } | |
| /* need same numbers of SG (with same length) for source and destination */ | |
| in_sg = areq->src; | |
| out_sg = areq->dst; | |
| while (in_sg && out_sg) { | |
| if (in_sg->length != out_sg->length) { | |
| ce->fallback_not_same_len++; | |
| return true; | |
| } | |
| in_sg = sg_next(in_sg); | |
| out_sg = sg_next(out_sg); | |
| } | |
| if (in_sg || out_sg) | |
| return true; | |
| return false; | |
| } | |
| static int sl3516_ce_cipher_fallback(struct skcipher_request *areq) | |
| { | |
| struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq); | |
| struct sl3516_ce_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm); | |
| struct sl3516_ce_cipher_req_ctx *rctx = skcipher_request_ctx(areq); | |
| struct skcipher_alg *alg = crypto_skcipher_alg(tfm); | |
| struct sl3516_ce_alg_template *algt; | |
| int err; | |
| algt = container_of(alg, struct sl3516_ce_alg_template, alg.skcipher.base); | |
| algt->stat_fb++; | |
| skcipher_request_set_tfm(&rctx->fallback_req, op->fallback_tfm); | |
| skcipher_request_set_callback(&rctx->fallback_req, areq->base.flags, | |
| areq->base.complete, areq->base.data); | |
| skcipher_request_set_crypt(&rctx->fallback_req, areq->src, areq->dst, | |
| areq->cryptlen, areq->iv); | |
| if (rctx->op_dir == CE_DECRYPTION) | |
| err = crypto_skcipher_decrypt(&rctx->fallback_req); | |
| else | |
| err = crypto_skcipher_encrypt(&rctx->fallback_req); | |
| return err; | |
| } | |
| static int sl3516_ce_cipher(struct skcipher_request *areq) | |
| { | |
| struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq); | |
| struct sl3516_ce_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm); | |
| struct sl3516_ce_dev *ce = op->ce; | |
| struct sl3516_ce_cipher_req_ctx *rctx = skcipher_request_ctx(areq); | |
| struct skcipher_alg *alg = crypto_skcipher_alg(tfm); | |
| struct sl3516_ce_alg_template *algt; | |
| struct scatterlist *sg; | |
| unsigned int todo, len; | |
| struct pkt_control_ecb *ecb; | |
| int nr_sgs = 0; | |
| int nr_sgd = 0; | |
| int err = 0; | |
| int i; | |
| algt = container_of(alg, struct sl3516_ce_alg_template, alg.skcipher.base); | |
| dev_dbg(ce->dev, "%s %s %u %x IV(%p %u) key=%u\n", __func__, | |
| crypto_tfm_alg_name(areq->base.tfm), | |
| areq->cryptlen, | |
| rctx->op_dir, areq->iv, crypto_skcipher_ivsize(tfm), | |
| op->keylen); | |
| algt->stat_req++; | |
| if (areq->src == areq->dst) { | |
| nr_sgs = dma_map_sg(ce->dev, areq->src, sg_nents(areq->src), | |
| DMA_BIDIRECTIONAL); | |
| if (nr_sgs <= 0 || nr_sgs > MAXDESC / 2) { | |
| dev_err(ce->dev, "Invalid sg number %d\n", nr_sgs); | |
| err = -EINVAL; | |
| goto theend; | |
| } | |
| nr_sgd = nr_sgs; | |
| } else { | |
| nr_sgs = dma_map_sg(ce->dev, areq->src, sg_nents(areq->src), | |
| DMA_TO_DEVICE); | |
| if (nr_sgs <= 0 || nr_sgs > MAXDESC / 2) { | |
| dev_err(ce->dev, "Invalid sg number %d\n", nr_sgs); | |
| err = -EINVAL; | |
| goto theend; | |
| } | |
| nr_sgd = dma_map_sg(ce->dev, areq->dst, sg_nents(areq->dst), | |
| DMA_FROM_DEVICE); | |
| if (nr_sgd <= 0 || nr_sgd > MAXDESC) { | |
| dev_err(ce->dev, "Invalid sg number %d\n", nr_sgd); | |
| err = -EINVAL; | |
| goto theend_sgs; | |
| } | |
| } | |
| len = areq->cryptlen; | |
| i = 0; | |
| sg = areq->src; | |
| while (i < nr_sgs && sg && len) { | |
| if (sg_dma_len(sg) == 0) | |
| goto sgs_next; | |
| rctx->t_src[i].addr = sg_dma_address(sg); | |
| todo = min(len, sg_dma_len(sg)); | |
| rctx->t_src[i].len = todo; | |
| dev_dbg(ce->dev, "%s total=%u SGS(%d %u off=%d) todo=%u\n", __func__, | |
| areq->cryptlen, i, rctx->t_src[i].len, sg->offset, todo); | |
| len -= todo; | |
| i++; | |
| sgs_next: | |
| sg = sg_next(sg); | |
| } | |
| if (len > 0) { | |
| dev_err(ce->dev, "remaining len %d/%u nr_sgs=%d\n", len, areq->cryptlen, nr_sgs); | |
| err = -EINVAL; | |
| goto theend_sgs; | |
| } | |
| len = areq->cryptlen; | |
| i = 0; | |
| sg = areq->dst; | |
| while (i < nr_sgd && sg && len) { | |
| if (sg_dma_len(sg) == 0) | |
| goto sgd_next; | |
| rctx->t_dst[i].addr = sg_dma_address(sg); | |
| todo = min(len, sg_dma_len(sg)); | |
| rctx->t_dst[i].len = todo; | |
| dev_dbg(ce->dev, "%s total=%u SGD(%d %u off=%d) todo=%u\n", __func__, | |
| areq->cryptlen, i, rctx->t_dst[i].len, sg->offset, todo); | |
| len -= todo; | |
| i++; | |
| sgd_next: | |
| sg = sg_next(sg); | |
| } | |
| if (len > 0) { | |
| dev_err(ce->dev, "remaining len %d\n", len); | |
| err = -EINVAL; | |
| goto theend_sgs; | |
| } | |
| switch (algt->mode) { | |
| case ECB_AES: | |
| rctx->pctrllen = sizeof(struct pkt_control_ecb); | |
| ecb = (struct pkt_control_ecb *)ce->pctrl; | |
| rctx->tqflag = TQ0_TYPE_CTRL; | |
| rctx->tqflag |= TQ1_CIPHER; | |
| ecb->control.op_mode = rctx->op_dir; | |
| ecb->control.cipher_algorithm = ECB_AES; | |
| ecb->cipher.header_len = 0; | |
| ecb->cipher.algorithm_len = areq->cryptlen; | |
| cpu_to_be32_array((__be32 *)ecb->key, (u32 *)op->key, op->keylen / 4); | |
| rctx->h = &ecb->cipher; | |
| rctx->tqflag |= TQ4_KEY0; | |
| rctx->tqflag |= TQ5_KEY4; | |
| rctx->tqflag |= TQ6_KEY6; | |
| ecb->control.aesnk = op->keylen / 4; | |
| break; | |
| } | |
| rctx->nr_sgs = nr_sgs; | |
| rctx->nr_sgd = nr_sgd; | |
| err = sl3516_ce_run_task(ce, rctx, crypto_tfm_alg_name(areq->base.tfm)); | |
| theend_sgs: | |
| if (areq->src == areq->dst) { | |
| dma_unmap_sg(ce->dev, areq->src, sg_nents(areq->src), | |
| DMA_BIDIRECTIONAL); | |
| } else { | |
| dma_unmap_sg(ce->dev, areq->src, sg_nents(areq->src), | |
| DMA_TO_DEVICE); | |
| dma_unmap_sg(ce->dev, areq->dst, sg_nents(areq->dst), | |
| DMA_FROM_DEVICE); | |
| } | |
| theend: | |
| return err; | |
| } | |
| int sl3516_ce_handle_cipher_request(struct crypto_engine *engine, void *areq) | |
| { | |
| int err; | |
| struct skcipher_request *breq = container_of(areq, struct skcipher_request, base); | |
| err = sl3516_ce_cipher(breq); | |
| local_bh_disable(); | |
| crypto_finalize_skcipher_request(engine, breq, err); | |
| local_bh_enable(); | |
| return 0; | |
| } | |
| int sl3516_ce_skdecrypt(struct skcipher_request *areq) | |
| { | |
| struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq); | |
| struct sl3516_ce_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm); | |
| struct sl3516_ce_cipher_req_ctx *rctx = skcipher_request_ctx(areq); | |
| struct crypto_engine *engine; | |
| memset(rctx, 0, sizeof(struct sl3516_ce_cipher_req_ctx)); | |
| rctx->op_dir = CE_DECRYPTION; | |
| if (sl3516_ce_need_fallback(areq)) | |
| return sl3516_ce_cipher_fallback(areq); | |
| engine = op->ce->engine; | |
| return crypto_transfer_skcipher_request_to_engine(engine, areq); | |
| } | |
| int sl3516_ce_skencrypt(struct skcipher_request *areq) | |
| { | |
| struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq); | |
| struct sl3516_ce_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm); | |
| struct sl3516_ce_cipher_req_ctx *rctx = skcipher_request_ctx(areq); | |
| struct crypto_engine *engine; | |
| memset(rctx, 0, sizeof(struct sl3516_ce_cipher_req_ctx)); | |
| rctx->op_dir = CE_ENCRYPTION; | |
| if (sl3516_ce_need_fallback(areq)) | |
| return sl3516_ce_cipher_fallback(areq); | |
| engine = op->ce->engine; | |
| return crypto_transfer_skcipher_request_to_engine(engine, areq); | |
| } | |
| int sl3516_ce_cipher_init(struct crypto_tfm *tfm) | |
| { | |
| struct sl3516_ce_cipher_tfm_ctx *op = crypto_tfm_ctx(tfm); | |
| struct sl3516_ce_alg_template *algt; | |
| const char *name = crypto_tfm_alg_name(tfm); | |
| struct crypto_skcipher *sktfm = __crypto_skcipher_cast(tfm); | |
| struct skcipher_alg *alg = crypto_skcipher_alg(sktfm); | |
| int err; | |
| memset(op, 0, sizeof(struct sl3516_ce_cipher_tfm_ctx)); | |
| algt = container_of(alg, struct sl3516_ce_alg_template, alg.skcipher.base); | |
| op->ce = algt->ce; | |
| op->fallback_tfm = crypto_alloc_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK); | |
| if (IS_ERR(op->fallback_tfm)) { | |
| dev_err(op->ce->dev, "ERROR: Cannot allocate fallback for %s %ld\n", | |
| name, PTR_ERR(op->fallback_tfm)); | |
| return PTR_ERR(op->fallback_tfm); | |
| } | |
| crypto_skcipher_set_reqsize(sktfm, sizeof(struct sl3516_ce_cipher_req_ctx) + | |
| crypto_skcipher_reqsize(op->fallback_tfm)); | |
| dev_info(op->ce->dev, "Fallback for %s is %s\n", | |
| crypto_tfm_alg_driver_name(&sktfm->base), | |
| crypto_tfm_alg_driver_name(crypto_skcipher_tfm(op->fallback_tfm))); | |
| err = pm_runtime_get_sync(op->ce->dev); | |
| if (err < 0) | |
| goto error_pm; | |
| return 0; | |
| error_pm: | |
| pm_runtime_put_noidle(op->ce->dev); | |
| crypto_free_skcipher(op->fallback_tfm); | |
| return err; | |
| } | |
| void sl3516_ce_cipher_exit(struct crypto_tfm *tfm) | |
| { | |
| struct sl3516_ce_cipher_tfm_ctx *op = crypto_tfm_ctx(tfm); | |
| kfree_sensitive(op->key); | |
| crypto_free_skcipher(op->fallback_tfm); | |
| pm_runtime_put_sync_suspend(op->ce->dev); | |
| } | |
| int sl3516_ce_aes_setkey(struct crypto_skcipher *tfm, const u8 *key, | |
| unsigned int keylen) | |
| { | |
| struct sl3516_ce_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm); | |
| struct sl3516_ce_dev *ce = op->ce; | |
| switch (keylen) { | |
| case 128 / 8: | |
| break; | |
| case 192 / 8: | |
| break; | |
| case 256 / 8: | |
| break; | |
| default: | |
| dev_dbg(ce->dev, "ERROR: Invalid keylen %u\n", keylen); | |
| return -EINVAL; | |
| } | |
| kfree_sensitive(op->key); | |
| op->keylen = keylen; | |
| op->key = kmemdup(key, keylen, GFP_KERNEL | GFP_DMA); | |
| if (!op->key) | |
| return -ENOMEM; | |
| crypto_skcipher_clear_flags(op->fallback_tfm, CRYPTO_TFM_REQ_MASK); | |
| crypto_skcipher_set_flags(op->fallback_tfm, tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK); | |
| return crypto_skcipher_setkey(op->fallback_tfm, key, keylen); | |
| } |