blob: 29048da6f50a7f9c1f428dbe9b1a10cca163a180 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* amlogic-cipher.c - hardware cryptographic offloader for Amlogic GXL SoC
*
* Copyright (C) 2018-2019 Corentin LABBE <clabbe@baylibre.com>
*
* This file add support for AES cipher with 128,192,256 bits keysize in
* CBC and ECB mode.
*/
#include <linux/crypto.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <crypto/scatterwalk.h>
#include <linux/scatterlist.h>
#include <linux/dma-mapping.h>
#include <crypto/internal/skcipher.h>
#include "amlogic-gxl.h"
static int get_engine_number(struct meson_dev *mc)
{
return atomic_inc_return(&mc->flow) % MAXFLOW;
}
static bool meson_cipher_need_fallback(struct skcipher_request *areq)
{
struct scatterlist *src_sg = areq->src;
struct scatterlist *dst_sg = areq->dst;
if (areq->cryptlen == 0)
return true;
if (sg_nents(src_sg) != sg_nents(dst_sg))
return true;
/* KEY/IV descriptors use 3 desc */
if (sg_nents(src_sg) > MAXDESC - 3 || sg_nents(dst_sg) > MAXDESC - 3)
return true;
while (src_sg && dst_sg) {
if ((src_sg->length % 16) != 0)
return true;
if ((dst_sg->length % 16) != 0)
return true;
if (src_sg->length != dst_sg->length)
return true;
if (!IS_ALIGNED(src_sg->offset, sizeof(u32)))
return true;
if (!IS_ALIGNED(dst_sg->offset, sizeof(u32)))
return true;
src_sg = sg_next(src_sg);
dst_sg = sg_next(dst_sg);
}
return false;
}
static int meson_cipher_do_fallback(struct skcipher_request *areq)
{
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
struct meson_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
struct meson_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
int err;
#ifdef CONFIG_CRYPTO_DEV_AMLOGIC_GXL_DEBUG
struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
struct meson_alg_template *algt;
algt = container_of(alg, struct meson_alg_template, alg.skcipher.base);
algt->stat_fb++;
#endif
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 == MESON_DECRYPT)
err = crypto_skcipher_decrypt(&rctx->fallback_req);
else
err = crypto_skcipher_encrypt(&rctx->fallback_req);
return err;
}
static int meson_cipher(struct skcipher_request *areq)
{
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
struct meson_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
struct meson_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
struct meson_dev *mc = op->mc;
struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
struct meson_alg_template *algt;
int flow = rctx->flow;
unsigned int todo, eat, len;
struct scatterlist *src_sg = areq->src;
struct scatterlist *dst_sg = areq->dst;
struct meson_desc *desc;
int nr_sgs, nr_sgd;
int i, err = 0;
unsigned int keyivlen, ivsize, offset, tloffset;
dma_addr_t phykeyiv;
void *backup_iv = NULL, *bkeyiv;
u32 v;
algt = container_of(alg, struct meson_alg_template, alg.skcipher.base);
dev_dbg(mc->dev, "%s %s %u %x IV(%u) key=%u flow=%d\n", __func__,
crypto_tfm_alg_name(areq->base.tfm),
areq->cryptlen,
rctx->op_dir, crypto_skcipher_ivsize(tfm),
op->keylen, flow);
#ifdef CONFIG_CRYPTO_DEV_AMLOGIC_GXL_DEBUG
algt->stat_req++;
mc->chanlist[flow].stat_req++;
#endif
/*
* The hardware expect a list of meson_desc structures.
* The 2 first structures store key
* The third stores IV
*/
bkeyiv = kzalloc(48, GFP_KERNEL | GFP_DMA);
if (!bkeyiv)
return -ENOMEM;
memcpy(bkeyiv, op->key, op->keylen);
keyivlen = op->keylen;
ivsize = crypto_skcipher_ivsize(tfm);
if (areq->iv && ivsize > 0) {
if (ivsize > areq->cryptlen) {
dev_err(mc->dev, "invalid ivsize=%d vs len=%d\n", ivsize, areq->cryptlen);
err = -EINVAL;
goto theend;
}
memcpy(bkeyiv + 32, areq->iv, ivsize);
keyivlen = 48;
if (rctx->op_dir == MESON_DECRYPT) {
backup_iv = kzalloc(ivsize, GFP_KERNEL);
if (!backup_iv) {
err = -ENOMEM;
goto theend;
}
offset = areq->cryptlen - ivsize;
scatterwalk_map_and_copy(backup_iv, areq->src, offset,
ivsize, 0);
}
}
if (keyivlen == 24)
keyivlen = 32;
phykeyiv = dma_map_single(mc->dev, bkeyiv, keyivlen,
DMA_TO_DEVICE);
err = dma_mapping_error(mc->dev, phykeyiv);
if (err) {
dev_err(mc->dev, "Cannot DMA MAP KEY IV\n");
goto theend;
}
tloffset = 0;
eat = 0;
i = 0;
while (keyivlen > eat) {
desc = &mc->chanlist[flow].tl[tloffset];
memset(desc, 0, sizeof(struct meson_desc));
todo = min(keyivlen - eat, 16u);
desc->t_src = cpu_to_le32(phykeyiv + i * 16);
desc->t_dst = cpu_to_le32(i * 16);
v = (MODE_KEY << 20) | DESC_OWN | 16;
desc->t_status = cpu_to_le32(v);
eat += todo;
i++;
tloffset++;
}
if (areq->src == areq->dst) {
nr_sgs = dma_map_sg(mc->dev, areq->src, sg_nents(areq->src),
DMA_BIDIRECTIONAL);
if (!nr_sgs) {
dev_err(mc->dev, "Invalid SG count %d\n", nr_sgs);
err = -EINVAL;
goto theend;
}
nr_sgd = nr_sgs;
} else {
nr_sgs = dma_map_sg(mc->dev, areq->src, sg_nents(areq->src),
DMA_TO_DEVICE);
if (!nr_sgs || nr_sgs > MAXDESC - 3) {
dev_err(mc->dev, "Invalid SG count %d\n", nr_sgs);
err = -EINVAL;
goto theend;
}
nr_sgd = dma_map_sg(mc->dev, areq->dst, sg_nents(areq->dst),
DMA_FROM_DEVICE);
if (!nr_sgd || nr_sgd > MAXDESC - 3) {
dev_err(mc->dev, "Invalid SG count %d\n", nr_sgd);
err = -EINVAL;
goto theend;
}
}
src_sg = areq->src;
dst_sg = areq->dst;
len = areq->cryptlen;
while (src_sg) {
desc = &mc->chanlist[flow].tl[tloffset];
memset(desc, 0, sizeof(struct meson_desc));
desc->t_src = cpu_to_le32(sg_dma_address(src_sg));
desc->t_dst = cpu_to_le32(sg_dma_address(dst_sg));
todo = min(len, sg_dma_len(src_sg));
v = (op->keymode << 20) | DESC_OWN | todo | (algt->blockmode << 26);
if (rctx->op_dir)
v |= DESC_ENCRYPTION;
len -= todo;
if (!sg_next(src_sg))
v |= DESC_LAST;
desc->t_status = cpu_to_le32(v);
tloffset++;
src_sg = sg_next(src_sg);
dst_sg = sg_next(dst_sg);
}
reinit_completion(&mc->chanlist[flow].complete);
mc->chanlist[flow].status = 0;
writel(mc->chanlist[flow].t_phy | 2, mc->base + (flow << 2));
wait_for_completion_interruptible_timeout(&mc->chanlist[flow].complete,
msecs_to_jiffies(500));
if (mc->chanlist[flow].status == 0) {
dev_err(mc->dev, "DMA timeout for flow %d\n", flow);
err = -EINVAL;
}
dma_unmap_single(mc->dev, phykeyiv, keyivlen, DMA_TO_DEVICE);
if (areq->src == areq->dst) {
dma_unmap_sg(mc->dev, areq->src, sg_nents(areq->src), DMA_BIDIRECTIONAL);
} else {
dma_unmap_sg(mc->dev, areq->src, sg_nents(areq->src), DMA_TO_DEVICE);
dma_unmap_sg(mc->dev, areq->dst, sg_nents(areq->dst), DMA_FROM_DEVICE);
}
if (areq->iv && ivsize > 0) {
if (rctx->op_dir == MESON_DECRYPT) {
memcpy(areq->iv, backup_iv, ivsize);
} else {
scatterwalk_map_and_copy(areq->iv, areq->dst,
areq->cryptlen - ivsize,
ivsize, 0);
}
}
theend:
kfree_sensitive(bkeyiv);
kfree_sensitive(backup_iv);
return err;
}
int meson_handle_cipher_request(struct crypto_engine *engine, void *areq)
{
int err;
struct skcipher_request *breq = container_of(areq, struct skcipher_request, base);
err = meson_cipher(breq);
local_bh_disable();
crypto_finalize_skcipher_request(engine, breq, err);
local_bh_enable();
return 0;
}
int meson_skdecrypt(struct skcipher_request *areq)
{
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
struct meson_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
struct meson_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
struct crypto_engine *engine;
int e;
rctx->op_dir = MESON_DECRYPT;
if (meson_cipher_need_fallback(areq))
return meson_cipher_do_fallback(areq);
e = get_engine_number(op->mc);
engine = op->mc->chanlist[e].engine;
rctx->flow = e;
return crypto_transfer_skcipher_request_to_engine(engine, areq);
}
int meson_skencrypt(struct skcipher_request *areq)
{
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
struct meson_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
struct meson_cipher_req_ctx *rctx = skcipher_request_ctx(areq);
struct crypto_engine *engine;
int e;
rctx->op_dir = MESON_ENCRYPT;
if (meson_cipher_need_fallback(areq))
return meson_cipher_do_fallback(areq);
e = get_engine_number(op->mc);
engine = op->mc->chanlist[e].engine;
rctx->flow = e;
return crypto_transfer_skcipher_request_to_engine(engine, areq);
}
int meson_cipher_init(struct crypto_tfm *tfm)
{
struct meson_cipher_tfm_ctx *op = crypto_tfm_ctx(tfm);
struct meson_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);
memset(op, 0, sizeof(struct meson_cipher_tfm_ctx));
algt = container_of(alg, struct meson_alg_template, alg.skcipher.base);
op->mc = algt->mc;
op->fallback_tfm = crypto_alloc_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK);
if (IS_ERR(op->fallback_tfm)) {
dev_err(op->mc->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 meson_cipher_req_ctx) +
crypto_skcipher_reqsize(op->fallback_tfm));
return 0;
}
void meson_cipher_exit(struct crypto_tfm *tfm)
{
struct meson_cipher_tfm_ctx *op = crypto_tfm_ctx(tfm);
kfree_sensitive(op->key);
crypto_free_skcipher(op->fallback_tfm);
}
int meson_aes_setkey(struct crypto_skcipher *tfm, const u8 *key,
unsigned int keylen)
{
struct meson_cipher_tfm_ctx *op = crypto_skcipher_ctx(tfm);
struct meson_dev *mc = op->mc;
switch (keylen) {
case 128 / 8:
op->keymode = MODE_AES_128;
break;
case 192 / 8:
op->keymode = MODE_AES_192;
break;
case 256 / 8:
op->keymode = MODE_AES_256;
break;
default:
dev_dbg(mc->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;
return crypto_skcipher_setkey(op->fallback_tfm, key, keylen);
}