| // 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 ((sg_dma_len(sg) % 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 ((sg_dma_len(sg) % 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); |
| } |