[PATCH v7 06/33] crypto: rockchip: add fallback for cipher

Corentin Labbe
2022-05-08T19:15:23Z

The hardware does not handle 0 size length request, let's add a
fallback.
Furthermore fallback will be used for all unaligned case the hardware
cannot handle.

Fixes: ce0183cb6464b ("crypto: rockchip - switch to skcipher API")
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
---
drivers/crypto/Kconfig | 4 +
drivers/crypto/rockchip/rk3288_crypto.h | 2 +
.../crypto/rockchip/rk3288_crypto_skcipher.c | 97 ++++++++++++++++---
3 files changed, 90 insertions(+), 13 deletions(-)

diff --git a/drivers/crypto/Kconfig b/drivers/crypto/Kconfig
index 7b2d138bc83e..84ab14afcbd9 100644
--- a/drivers/crypto/Kconfig
+++ b/drivers/crypto/Kconfig
@@ -784,6 +784,10 @@ config CRYPTO_DEV_IMGTEC_HASH
config CRYPTO_DEV_ROCKCHIP
tristate "Rockchip's Cryptographic Engine driver"
depends on OF && ARCH_ROCKCHIP
+ depends on PM
+ select CRYPTO_ECB
+ select CRYPTO_CBC
+ select CRYPTO_DES
select CRYPTO_AES
select CRYPTO_LIB_DES
select CRYPTO_MD5
diff --git a/drivers/crypto/rockchip/rk3288_crypto.h b/drivers/crypto/rockchip/rk3288_crypto.h
index c919d9a43a08..8b1e15d8ddc6 100644
--- a/drivers/crypto/rockchip/rk3288_crypto.h
+++ b/drivers/crypto/rockchip/rk3288_crypto.h
@@ -246,10 +246,12 @@ struct rk_cipher_ctx {
struct rk_crypto_info *dev;
unsigned int keylen;
u8 iv[AES_BLOCK_SIZE];
+ struct crypto_skcipher *fallback_tfm;
};

struct rk_cipher_rctx {
u32 mode;
+ struct skcipher_request fallback_req; // keep at the end
};

enum alg_type {
diff --git a/drivers/crypto/rockchip/rk3288_crypto_skcipher.c b/drivers/crypto/rockchip/rk3288_crypto_skcipher.c
index bbd0bf52bf07..eac5bba66e25 100644
--- a/drivers/crypto/rockchip/rk3288_crypto_skcipher.c
+++ b/drivers/crypto/rockchip/rk3288_crypto_skcipher.c
@@ -13,6 +13,63 @@

#define RK_CRYPTO_DEC BIT(0)

+static int rk_cipher_need_fallback(struct skcipher_request *req)
+{
+ struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+ unsigned int bs = crypto_skcipher_blocksize(tfm);
+ struct scatterlist *sgs, *sgd;
+ unsigned int stodo, dtodo, len;
+
+ if (!req->cryptlen)
+ return true;
+
+ len = req->cryptlen;
+ sgs = req->src;
+ sgd = req->dst;
+ while (sgs && sgd) {
+ if (!IS_ALIGNED(sgs->offset, sizeof(u32))) {
+ return true;
+ }
+ if (!IS_ALIGNED(sgd->offset, sizeof(u32))) {
+ return true;
+ }
+ stodo = min(len, sgs->length);
+ if (stodo % bs) {
+ return true;
+ }
+ dtodo = min(len, sgd->length);
+ if (dtodo % bs) {
+ return true;
+ }
+ if (stodo != dtodo) {
+ return true;
+ }
+ len -= stodo;
+ sgs = sg_next(sgs);
+ sgd = sg_next(sgd);
+ }
+ return false;
+}
+
+static int rk_cipher_fallback(struct skcipher_request *areq)
+{
+ struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(areq);
+ struct rk_cipher_ctx *op = crypto_skcipher_ctx(tfm);
+ struct rk_cipher_rctx *rctx = skcipher_request_ctx(areq);
+ int err;
+
+ 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->mode & RK_CRYPTO_DEC)
+ err = crypto_skcipher_decrypt(&rctx->fallback_req);
+ else
+ err = crypto_skcipher_encrypt(&rctx->fallback_req);
+ return err;
+}
+
static void rk_crypto_complete(struct crypto_async_request *base, int err)
{
if (base->complete)
@@ -22,10 +79,10 @@ static void rk_crypto_complete(struct crypto_async_request *base, int err)
static int rk_handle_req(struct rk_crypto_info *dev,
struct skcipher_request *req)
{
- if (!IS_ALIGNED(req->cryptlen, dev->align_size))
- return -EINVAL;
- else
- return dev->enqueue(dev, &req->base);
+ if (rk_cipher_need_fallback(req))
+ return rk_cipher_fallback(req);
+
+ return dev->enqueue(dev, &req->base);
}

static int rk_aes_setkey(struct crypto_skcipher *cipher,
@@ -39,7 +96,8 @@ static int rk_aes_setkey(struct crypto_skcipher *cipher,
return -EINVAL;
ctx->keylen = keylen;
memcpy_toio(ctx->dev->reg + RK_CRYPTO_AES_KEY_0, key, keylen);
- return 0;
+
+ return crypto_skcipher_setkey(ctx->fallback_tfm, key, keylen);
}

static int rk_des_setkey(struct crypto_skcipher *cipher,
@@ -54,7 +112,8 @@ static int rk_des_setkey(struct crypto_skcipher *cipher,

ctx->keylen = keylen;
memcpy_toio(ctx->dev->reg + RK_CRYPTO_TDES_KEY1_0, key, keylen);
- return 0;
+
+ return crypto_skcipher_setkey(ctx->fallback_tfm, key, keylen);
}

static int rk_tdes_setkey(struct crypto_skcipher *cipher,
@@ -69,7 +128,7 @@ static int rk_tdes_setkey(struct crypto_skcipher *cipher,

ctx->keylen = keylen;
memcpy_toio(ctx->dev->reg + RK_CRYPTO_TDES_KEY1_0, key, keylen);
- return 0;
+ return crypto_skcipher_setkey(ctx->fallback_tfm, key, keylen);
}

static int rk_aes_ecb_encrypt(struct skcipher_request *req)
@@ -394,6 +453,7 @@ static int rk_ablk_init_tfm(struct crypto_skcipher *tfm)
{
struct rk_cipher_ctx *ctx = crypto_skcipher_ctx(tfm);
struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
+ const char *name = crypto_tfm_alg_name(&tfm->base);
struct rk_crypto_tmp *algt;

algt = container_of(alg, struct rk_crypto_tmp, alg.skcipher);
@@ -407,6 +467,16 @@ static int rk_ablk_init_tfm(struct crypto_skcipher *tfm)
if (!ctx->dev->addr_vir)
return -ENOMEM;

+ ctx->fallback_tfm = crypto_alloc_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK);
+ if (IS_ERR(ctx->fallback_tfm)) {
+ dev_err(ctx->dev->dev, "ERROR: Cannot allocate fallback for %s %ld\n",
+ name, PTR_ERR(ctx->fallback_tfm));
+ return PTR_ERR(ctx->fallback_tfm);
+ }
+
+ tfm->reqsize = sizeof(struct rk_cipher_rctx) +
+ crypto_skcipher_reqsize(ctx->fallback_tfm);
+
return 0;
}

@@ -415,6 +485,7 @@ static void rk_ablk_exit_tfm(struct crypto_skcipher *tfm)
struct rk_cipher_ctx *ctx = crypto_skcipher_ctx(tfm);

free_page((unsigned long)ctx->dev->addr_vir);
+ crypto_free_skcipher(ctx->fallback_tfm);
}

struct rk_crypto_tmp rk_ecb_aes_alg = {
@@ -423,7 +494,7 @@ struct rk_crypto_tmp rk_ecb_aes_alg = {
.base.cra_name = "ecb(aes)",
.base.cra_driver_name = "ecb-aes-rk",
.base.cra_priority = 300,
- .base.cra_flags = CRYPTO_ALG_ASYNC,
+ .base.cra_flags = CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK,
.base.cra_blocksize = AES_BLOCK_SIZE,
.base.cra_ctxsize = sizeof(struct rk_cipher_ctx),
.base.cra_alignmask = 0x0f,
@@ -445,7 +516,7 @@ struct rk_crypto_tmp rk_cbc_aes_alg = {
.base.cra_name = "cbc(aes)",
.base.cra_driver_name = "cbc-aes-rk",
.base.cra_priority = 300,
- .base.cra_flags = CRYPTO_ALG_ASYNC,
+ .base.cra_flags = CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK,
.base.cra_blocksize = AES_BLOCK_SIZE,
.base.cra_ctxsize = sizeof(struct rk_cipher_ctx),
.base.cra_alignmask = 0x0f,
@@ -468,7 +539,7 @@ struct rk_crypto_tmp rk_ecb_des_alg = {
.base.cra_name = "ecb(des)",
.base.cra_driver_name = "ecb-des-rk",
.base.cra_priority = 300,
- .base.cra_flags = CRYPTO_ALG_ASYNC,
+ .base.cra_flags = CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK,
.base.cra_blocksize = DES_BLOCK_SIZE,
.base.cra_ctxsize = sizeof(struct rk_cipher_ctx),
.base.cra_alignmask = 0x07,
@@ -490,7 +561,7 @@ struct rk_crypto_tmp rk_cbc_des_alg = {
.base.cra_name = "cbc(des)",
.base.cra_driver_name = "cbc-des-rk",
.base.cra_priority = 300,
- .base.cra_flags = CRYPTO_ALG_ASYNC,
+ .base.cra_flags = CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK,
.base.cra_blocksize = DES_BLOCK_SIZE,
.base.cra_ctxsize = sizeof(struct rk_cipher_ctx),
.base.cra_alignmask = 0x07,
@@ -513,7 +584,7 @@ struct rk_crypto_tmp rk_ecb_des3_ede_alg = {
.base.cra_name = "ecb(des3_ede)",
.base.cra_driver_name = "ecb-des3-ede-rk",
.base.cra_priority = 300,
- .base.cra_flags = CRYPTO_ALG_ASYNC,
+ .base.cra_flags = CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK,
.base.cra_blocksize = DES_BLOCK_SIZE,
.base.cra_ctxsize = sizeof(struct rk_cipher_ctx),
.base.cra_alignmask = 0x07,
@@ -535,7 +606,7 @@ struct rk_crypto_tmp rk_cbc_des3_ede_alg = {
.base.cra_name = "cbc(des3_ede)",
.base.cra_driver_name = "cbc-des3-ede-rk",
.base.cra_priority = 300,
- .base.cra_flags = CRYPTO_ALG_ASYNC,
+ .base.cra_flags = CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK,
.base.cra_blocksize = DES_BLOCK_SIZE,
.base.cra_ctxsize = sizeof(struct rk_cipher_ctx),
.base.cra_alignmask = 0x07,