diff mbox series

[v2,06/18] crypto: rockchip: add fallback for cipher

Message ID 20220302211113.4003816-7-clabbe@baylibre.com (mailing list archive)
State Changes Requested
Delegated to: Herbert Xu
Headers show
Series crypto: rockchip: permit to pass self-tests | expand

Commit Message

Corentin LABBE March 2, 2022, 9:11 p.m. UTC 
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/rockchip/rk3288_crypto.h       |  2 +
 .../crypto/rockchip/rk3288_crypto_skcipher.c  | 97 ++++++++++++++++---
 2 files changed, 86 insertions(+), 13 deletions(-)

Comments

John Keeping March 3, 2022, 2:21 p.m. UTC | #1 
On Wed, Mar 02, 2022 at 09:11:01PM +0000, Corentin Labbe wrote:
> 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/rockchip/rk3288_crypto.h       |  2 +
>  .../crypto/rockchip/rk3288_crypto_skcipher.c  | 97 ++++++++++++++++---
>  2 files changed, 86 insertions(+), 13 deletions(-)
> 
> 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..bf9d398cc54c 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 scatterlist *sgs, *sgd;
> +
> +	if (!req->cryptlen)
> +		return true;
> +
> +	sgs = req->src;
> +	while (sgs) {
> +		if (!IS_ALIGNED(sgs->offset, sizeof(u32))) {
> +			return true;
> +		}
> +		if (sgs->length % 16) {

Can this be relaxed to check for alignment to 4 rather than 16?  That's
the requirement for programming the registers.

But I think this check is wrong in general as it doesn't account for
cryptlen; with fscrypt I'm seeing sgs->length == 255 but cryptlen == 16
so the hardware can be used but at the moment the fallback path is
triggered.
Corentin LABBE March 3, 2022, 7:54 p.m. UTC | #2 
Le Thu, Mar 03, 2022 at 02:21:37PM +0000, John Keeping a écrit :
> On Wed, Mar 02, 2022 at 09:11:01PM +0000, Corentin Labbe wrote:
> > 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/rockchip/rk3288_crypto.h       |  2 +
> >  .../crypto/rockchip/rk3288_crypto_skcipher.c  | 97 ++++++++++++++++---
> >  2 files changed, 86 insertions(+), 13 deletions(-)
> > 
> > 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..bf9d398cc54c 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 scatterlist *sgs, *sgd;
> > +
> > +	if (!req->cryptlen)
> > +		return true;
> > +
> > +	sgs = req->src;
> > +	while (sgs) {
> > +		if (!IS_ALIGNED(sgs->offset, sizeof(u32))) {
> > +			return true;
> > +		}
> > +		if (sgs->length % 16) {
> 
> Can this be relaxed to check for alignment to 4 rather than 16?  That's
> the requirement for programming the registers.

No we cannot, the hardware could operate only one SG at a time, and the cipher operation need to be complete, so the length should be a multiple of AES_BLOCK_SIZE.
The original driver already have this size check.
But for DES/3DES this check is bad and should be 8, so a fix is needed anyway.

> 
> But I think this check is wrong in general as it doesn't account for
> cryptlen; with fscrypt I'm seeing sgs->length == 255 but cryptlen == 16
> so the hardware can be used but at the moment the fallback path is
> triggered.

Yes, I need to check min(sg->length, cryptlen_remaining) instead.
I will fix that.

Thanks.
diff mbox series

Patch

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..bf9d398cc54c 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 scatterlist *sgs, *sgd;
+
+	if (!req->cryptlen)
+		return true;
+
+	sgs = req->src;
+	while (sgs) {
+		if (!IS_ALIGNED(sgs->offset, sizeof(u32))) {
+			return true;
+		}
+		if (sgs->length % 16) {
+			return true;
+		}
+		sgs = sg_next(sgs);
+	}
+	sgd = req->dst;
+	while (sgd) {
+		if (!IS_ALIGNED(sgd->offset, sizeof(u32))) {
+			return true;
+		}
+		if (sgd->length % 16) {
+			return true;
+		}
+		sgd = sg_next(sgd);
+	}
+	sgs = req->src;
+	sgd = req->dst;
+	while (sgs && sgd) {
+		if (sgs->length != sgd->length)
+			return true;
+		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,