linuxdebug/drivers/crypto/gemini/sl3516-ce-cipher.c

390 lines
10 KiB
C

// 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);
}