diff options
Diffstat (limited to 'drivers/crypto/gemini/sl3516-ce-cipher.c')
| -rw-r--r-- | drivers/crypto/gemini/sl3516-ce-cipher.c | 389 |
1 files changed, 389 insertions, 0 deletions
diff --git a/drivers/crypto/gemini/sl3516-ce-cipher.c b/drivers/crypto/gemini/sl3516-ce-cipher.c new file mode 100644 index 000000000..14d0d83d3 --- /dev/null +++ b/drivers/crypto/gemini/sl3516-ce-cipher.c @@ -0,0 +1,389 @@ +// 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 <linux/crypto.h> +#include <linux/dma-mapping.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/pm_runtime.h> +#include <crypto/scatterwalk.h> +#include <crypto/internal/skcipher.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); + 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); + + 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; +} + +static 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); + 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); + } + + sktfm->reqsize = 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))); + + op->enginectx.op.do_one_request = sl3516_ce_handle_cipher_request; + op->enginectx.op.prepare_request = NULL; + op->enginectx.op.unprepare_request = NULL; + + 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); +} |