diff mbox series

[v2] crypto: geode-aes - switch to skcipher for cbc(aes) fallback

Message ID 20191005091110.12556-1-ard.biesheuvel@linaro.org
State Accepted
Commit 504582e8e40b90b8f8c58783e2d1e4f6a2b71a3a
Headers show
Series [v2] crypto: geode-aes - switch to skcipher for cbc(aes) fallback | expand

Commit Message

Ard Biesheuvel Oct. 5, 2019, 9:11 a.m. UTC 
Commit 79c65d179a40e145 ("crypto: cbc - Convert to skcipher") updated
the generic CBC template wrapper from a blkcipher to a skcipher algo,
to get away from the deprecated blkcipher interface. However, as a side
effect, drivers that instantiate CBC transforms using the blkcipher as
a fallback no longer work, since skciphers can wrap blkciphers but not
the other way around. This broke the geode-aes driver.

So let's fix it by moving to the sync skcipher interface when allocating
the fallback. At the same time, align with the generic API for ECB and
CBC by rejecting inputs that are not a multiple of the AES block size.

Fixes: 79c65d179a40e145 ("crypto: cbc - Convert to skcipher")
Cc: <stable@vger.kernel.org> # v4.20+ ONLY
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

---
v2: pass dst and src scatterlist in the right order
    reject inputs that are not a multiple of the block size

 drivers/crypto/geode-aes.c | 57 +++++++++++---------
 drivers/crypto/geode-aes.h |  2 +-
 2 files changed, 34 insertions(+), 25 deletions(-)

-- 
2.20.1

Comments

Florian Bezdeka Oct. 5, 2019, 12:22 p.m. UTC | #1 
Commit 79c65d179a40e145 ("crypto: cbc - Convert to skcipher") updated
the generic CBC template wrapper from a blkcipher to a skcipher algo,
to get away from the deprecated blkcipher interface. However, as a side
effect, drivers that instantiate CBC transforms using the blkcipher as
a fallback no longer work, since skciphers can wrap blkciphers but not
the other way around. This broke the geode-aes driver.

So let's fix it by moving to the sync skcipher interface when allocating
the fallback. At the same time, align with the generic API for ECB and
CBC by rejecting inputs that are not a multiple of the AES block size.

Fixes: 79c65d179a40e145 ("crypto: cbc - Convert to skcipher")
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Florian Bezdeka <florian@bezdeka.de>

---

Ard, I just followed your instructions and created this patch 
for usage on an 4.19 kernel. The patch was successfully tested 
on two different Geode systems.

Can you please review again and forward to the stable tree if the patch
looks OK?

 drivers/crypto/geode-aes.c | 57 +++++++++++++++++++++++---------------
 drivers/crypto/geode-aes.h |  2 +-
 2 files changed, 35 insertions(+), 24 deletions(-)

diff --git a/drivers/crypto/geode-aes.c b/drivers/crypto/geode-aes.c
index eb2a0a73cbed..cc33354d13c1 100644
--- a/drivers/crypto/geode-aes.c
+++ b/drivers/crypto/geode-aes.c
@@ -14,6 +14,7 @@
 #include <linux/spinlock.h>
 #include <crypto/algapi.h>
 #include <crypto/aes.h>
+#include <crypto/skcipher.h>
 
 #include <linux/io.h>
 #include <linux/delay.h>
@@ -170,13 +171,15 @@ static int geode_setkey_blk(struct crypto_tfm *tfm, const u8 *key,
 	/*
 	 * The requested key size is not supported by HW, do a fallback
 	 */
-	op->fallback.blk->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK;
-	op->fallback.blk->base.crt_flags |= (tfm->crt_flags & CRYPTO_TFM_REQ_MASK);
+	crypto_skcipher_clear_flags(op->fallback.blk, CRYPTO_TFM_REQ_MASK);
+	crypto_skcipher_set_flags(op->fallback.blk,
+				  tfm->crt_flags & CRYPTO_TFM_REQ_MASK);
 
-	ret = crypto_blkcipher_setkey(op->fallback.blk, key, len);
+	ret = crypto_skcipher_setkey(op->fallback.blk, key, len);
 	if (ret) {
 		tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK;
-		tfm->crt_flags |= (op->fallback.blk->base.crt_flags & CRYPTO_TFM_RES_MASK);
+		tfm->crt_flags |= crypto_skcipher_get_flags(op->fallback.blk) &
+				  CRYPTO_TFM_RES_MASK;
 	}
 	return ret;
 }
@@ -185,33 +188,28 @@ static int fallback_blk_dec(struct blkcipher_desc *desc,
 		struct scatterlist *dst, struct scatterlist *src,
 		unsigned int nbytes)
 {
-	unsigned int ret;
-	struct crypto_blkcipher *tfm;
 	struct geode_aes_op *op = crypto_blkcipher_ctx(desc->tfm);
+	SKCIPHER_REQUEST_ON_STACK(req, op->fallback.blk);
 
-	tfm = desc->tfm;
-	desc->tfm = op->fallback.blk;
-
-	ret = crypto_blkcipher_decrypt_iv(desc, dst, src, nbytes);
+	skcipher_request_set_tfm(req, op->fallback.blk);
+	skcipher_request_set_callback(req, 0, NULL, NULL);
+	skcipher_request_set_crypt(req, src, dst, nbytes, desc->info);
 
-	desc->tfm = tfm;
-	return ret;
+	return crypto_skcipher_decrypt(req);
 }
+
 static int fallback_blk_enc(struct blkcipher_desc *desc,
 		struct scatterlist *dst, struct scatterlist *src,
 		unsigned int nbytes)
 {
-	unsigned int ret;
-	struct crypto_blkcipher *tfm;
 	struct geode_aes_op *op = crypto_blkcipher_ctx(desc->tfm);
+	SKCIPHER_REQUEST_ON_STACK(req, op->fallback.blk);
 
-	tfm = desc->tfm;
-	desc->tfm = op->fallback.blk;
-
-	ret = crypto_blkcipher_encrypt_iv(desc, dst, src, nbytes);
+	skcipher_request_set_tfm(req, op->fallback.blk);
+	skcipher_request_set_callback(req, 0, NULL, NULL);
+	skcipher_request_set_crypt(req, src, dst, nbytes, desc->info);
 
-	desc->tfm = tfm;
-	return ret;
+	return crypto_skcipher_encrypt(req);
 }
 
 static void
@@ -311,6 +309,9 @@ geode_cbc_decrypt(struct blkcipher_desc *desc,
 	struct blkcipher_walk walk;
 	int err, ret;
 
+	if (nbytes % AES_BLOCK_SIZE)
+		return -EINVAL;
+
 	if (unlikely(op->keylen != AES_KEYSIZE_128))
 		return fallback_blk_dec(desc, dst, src, nbytes);
 
@@ -343,6 +344,9 @@ geode_cbc_encrypt(struct blkcipher_desc *desc,
 	struct blkcipher_walk walk;
 	int err, ret;
 
+	if (nbytes % AES_BLOCK_SIZE)
+		return -EINVAL;
+
 	if (unlikely(op->keylen != AES_KEYSIZE_128))
 		return fallback_blk_enc(desc, dst, src, nbytes);
 
@@ -370,8 +374,9 @@ static int fallback_init_blk(struct crypto_tfm *tfm)
 	const char *name = crypto_tfm_alg_name(tfm);
 	struct geode_aes_op *op = crypto_tfm_ctx(tfm);
 
-	op->fallback.blk = crypto_alloc_blkcipher(name, 0,
-			CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK);
+	op->fallback.blk = crypto_alloc_skcipher(name, 0,
+						 CRYPTO_ALG_ASYNC | 
+						 CRYPTO_ALG_NEED_FALLBACK);
 
 	if (IS_ERR(op->fallback.blk)) {
 		printk(KERN_ERR "Error allocating fallback algo %s\n", name);
@@ -385,7 +390,7 @@ static void fallback_exit_blk(struct crypto_tfm *tfm)
 {
 	struct geode_aes_op *op = crypto_tfm_ctx(tfm);
 
-	crypto_free_blkcipher(op->fallback.blk);
+	crypto_free_skcipher(op->fallback.blk);
 	op->fallback.blk = NULL;
 }
 
@@ -424,6 +429,9 @@ geode_ecb_decrypt(struct blkcipher_desc *desc,
 	struct blkcipher_walk walk;
 	int err, ret;
 
+	if (nbytes % AES_BLOCK_SIZE)
+		return -EINVAL;
+
 	if (unlikely(op->keylen != AES_KEYSIZE_128))
 		return fallback_blk_dec(desc, dst, src, nbytes);
 
@@ -454,6 +462,9 @@ geode_ecb_encrypt(struct blkcipher_desc *desc,
 	struct blkcipher_walk walk;
 	int err, ret;
 
+	if (nbytes % AES_BLOCK_SIZE)
+		return -EINVAL;
+
 	if (unlikely(op->keylen != AES_KEYSIZE_128))
 		return fallback_blk_enc(desc, dst, src, nbytes);
 
diff --git a/drivers/crypto/geode-aes.h b/drivers/crypto/geode-aes.h
index f442ca972e3c..c5763a041bb8 100644
--- a/drivers/crypto/geode-aes.h
+++ b/drivers/crypto/geode-aes.h
@@ -64,7 +64,7 @@ struct geode_aes_op {
 	u8 *iv;
 
 	union {
-		struct crypto_blkcipher *blk;
+		struct crypto_skcipher *blk;
 		struct crypto_cipher *cip;
 	} fallback;
 	u32 keylen;
-- 
2.21.0
Gert Robben Oct. 5, 2019, 4:15 p.m. UTC | #2 
Op 05-10-2019 om 11:11 schreef Ard Biesheuvel:
> Commit 79c65d179a40e145 ("crypto: cbc - Convert to skcipher") updated

> the generic CBC template wrapper from a blkcipher to a skcipher algo,

> to get away from the deprecated blkcipher interface. However, as a side

> effect, drivers that instantiate CBC transforms using the blkcipher as

> a fallback no longer work, since skciphers can wrap blkciphers but not

> the other way around. This broke the geode-aes driver.

> 

> So let's fix it by moving to the sync skcipher interface when allocating

> the fallback. At the same time, align with the generic API for ECB and

> CBC by rejecting inputs that are not a multiple of the AES block size.

> 

> Fixes: 79c65d179a40e145 ("crypto: cbc - Convert to skcipher")

> Cc: <stable@vger.kernel.org> # v4.20+ ONLY

> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

> ---

> v2: pass dst and src scatterlist in the right order

>      reject inputs that are not a multiple of the block size


Yes, with this patch, the CRYPTO_MANAGER_EXTRA_TESTS output nothing 
(apart from "extra crypto tests enabled").
All items in /proc/crypto have "selftest: passed" mentioned.
"openssl speed -evp aes-128-cbc -elapsed -engine afalg" reaches the 
proper speed.
And nginx (correctly) transfers files about 40% faster than without 
geode-aes.

I didn't think about testing ecb before, because I don't use it.
Now that I did, I tried the same openssl benchmark for ecb.
But that only reaches software AES speed, and "time" also shows the work 
is being done in "user" instead of "sys" (see below).
Yet I see no errors.
(Maybe this is normal/expected, so I didn't look much further into it).

Thank you,
Gert

# time openssl speed -evp aes-128-cbc -elapsed -engine afalg
- - - 8< - - -
type             16 bytes     64 bytes    256 bytes   1024 bytes   8192 
bytes  16384 bytes
aes-128-cbc        135.82k      539.29k     2087.90k     7491.16k 
29221.69k    34943.67k

real	0m18.081s
user	0m0.516s
sys	0m17.541s

# time openssl speed -evp aes-128-ecb -elapsed -engine afalg
- - - 8< - - -
type             16 bytes     64 bytes    256 bytes   1024 bytes   8192 
bytes  16384 bytes
aes-128-ecb       4480.65k     5137.66k     5336.94k     5410.19k 
5409.91k     5409.91k

real	0m18.084s
user	0m18.046s
sys	0m0.012s
Ard Biesheuvel Oct. 8, 2019, 11:36 a.m. UTC | #3 
On Sat, 5 Oct 2019 at 14:22, Florian Bezdeka <florian@bezdeka.de> wrote:
>

> Commit 79c65d179a40e145 ("crypto: cbc - Convert to skcipher") updated

> the generic CBC template wrapper from a blkcipher to a skcipher algo,

> to get away from the deprecated blkcipher interface. However, as a side

> effect, drivers that instantiate CBC transforms using the blkcipher as

> a fallback no longer work, since skciphers can wrap blkciphers but not

> the other way around. This broke the geode-aes driver.

>

> So let's fix it by moving to the sync skcipher interface when allocating

> the fallback. At the same time, align with the generic API for ECB and

> CBC by rejecting inputs that are not a multiple of the AES block size.

>

> Fixes: 79c65d179a40e145 ("crypto: cbc - Convert to skcipher")

> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>

> Signed-off-by: Florian Bezdeka <florian@bezdeka.de>

> ---

>

> Ard, I just followed your instructions and created this patch

> for usage on an 4.19 kernel. The patch was successfully tested

> on two different Geode systems.

>

> Can you please review again and forward to the stable tree if the patch

> looks OK?

>


The patch looks fine to me, but we cannot send it to -stable before
the mainline version is merged.

>  drivers/crypto/geode-aes.c | 57 +++++++++++++++++++++++---------------

>  drivers/crypto/geode-aes.h |  2 +-

>  2 files changed, 35 insertions(+), 24 deletions(-)

>

> diff --git a/drivers/crypto/geode-aes.c b/drivers/crypto/geode-aes.c

> index eb2a0a73cbed..cc33354d13c1 100644

> --- a/drivers/crypto/geode-aes.c

> +++ b/drivers/crypto/geode-aes.c

> @@ -14,6 +14,7 @@

>  #include <linux/spinlock.h>

>  #include <crypto/algapi.h>

>  #include <crypto/aes.h>

> +#include <crypto/skcipher.h>

>

>  #include <linux/io.h>

>  #include <linux/delay.h>

> @@ -170,13 +171,15 @@ static int geode_setkey_blk(struct crypto_tfm *tfm, const u8 *key,

>         /*

>          * The requested key size is not supported by HW, do a fallback

>          */

> -       op->fallback.blk->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK;

> -       op->fallback.blk->base.crt_flags |= (tfm->crt_flags & CRYPTO_TFM_REQ_MASK);

> +       crypto_skcipher_clear_flags(op->fallback.blk, CRYPTO_TFM_REQ_MASK);

> +       crypto_skcipher_set_flags(op->fallback.blk,

> +                                 tfm->crt_flags & CRYPTO_TFM_REQ_MASK);

>

> -       ret = crypto_blkcipher_setkey(op->fallback.blk, key, len);

> +       ret = crypto_skcipher_setkey(op->fallback.blk, key, len);

>         if (ret) {

>                 tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK;

> -               tfm->crt_flags |= (op->fallback.blk->base.crt_flags & CRYPTO_TFM_RES_MASK);

> +               tfm->crt_flags |= crypto_skcipher_get_flags(op->fallback.blk) &

> +                                 CRYPTO_TFM_RES_MASK;

>         }

>         return ret;

>  }

> @@ -185,33 +188,28 @@ static int fallback_blk_dec(struct blkcipher_desc *desc,

>                 struct scatterlist *dst, struct scatterlist *src,

>                 unsigned int nbytes)

>  {

> -       unsigned int ret;

> -       struct crypto_blkcipher *tfm;

>         struct geode_aes_op *op = crypto_blkcipher_ctx(desc->tfm);

> +       SKCIPHER_REQUEST_ON_STACK(req, op->fallback.blk);

>

> -       tfm = desc->tfm;

> -       desc->tfm = op->fallback.blk;

> -

> -       ret = crypto_blkcipher_decrypt_iv(desc, dst, src, nbytes);

> +       skcipher_request_set_tfm(req, op->fallback.blk);

> +       skcipher_request_set_callback(req, 0, NULL, NULL);

> +       skcipher_request_set_crypt(req, src, dst, nbytes, desc->info);

>

> -       desc->tfm = tfm;

> -       return ret;

> +       return crypto_skcipher_decrypt(req);

>  }

> +

>  static int fallback_blk_enc(struct blkcipher_desc *desc,

>                 struct scatterlist *dst, struct scatterlist *src,

>                 unsigned int nbytes)

>  {

> -       unsigned int ret;

> -       struct crypto_blkcipher *tfm;

>         struct geode_aes_op *op = crypto_blkcipher_ctx(desc->tfm);

> +       SKCIPHER_REQUEST_ON_STACK(req, op->fallback.blk);

>

> -       tfm = desc->tfm;

> -       desc->tfm = op->fallback.blk;

> -

> -       ret = crypto_blkcipher_encrypt_iv(desc, dst, src, nbytes);

> +       skcipher_request_set_tfm(req, op->fallback.blk);

> +       skcipher_request_set_callback(req, 0, NULL, NULL);

> +       skcipher_request_set_crypt(req, src, dst, nbytes, desc->info);

>

> -       desc->tfm = tfm;

> -       return ret;

> +       return crypto_skcipher_encrypt(req);

>  }

>

>  static void

> @@ -311,6 +309,9 @@ geode_cbc_decrypt(struct blkcipher_desc *desc,

>         struct blkcipher_walk walk;

>         int err, ret;

>

> +       if (nbytes % AES_BLOCK_SIZE)

> +               return -EINVAL;

> +

>         if (unlikely(op->keylen != AES_KEYSIZE_128))

>                 return fallback_blk_dec(desc, dst, src, nbytes);

>

> @@ -343,6 +344,9 @@ geode_cbc_encrypt(struct blkcipher_desc *desc,

>         struct blkcipher_walk walk;

>         int err, ret;

>

> +       if (nbytes % AES_BLOCK_SIZE)

> +               return -EINVAL;

> +

>         if (unlikely(op->keylen != AES_KEYSIZE_128))

>                 return fallback_blk_enc(desc, dst, src, nbytes);

>

> @@ -370,8 +374,9 @@ static int fallback_init_blk(struct crypto_tfm *tfm)

>         const char *name = crypto_tfm_alg_name(tfm);

>         struct geode_aes_op *op = crypto_tfm_ctx(tfm);

>

> -       op->fallback.blk = crypto_alloc_blkcipher(name, 0,

> -                       CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK);

> +       op->fallback.blk = crypto_alloc_skcipher(name, 0,

> +                                                CRYPTO_ALG_ASYNC |

> +                                                CRYPTO_ALG_NEED_FALLBACK);

>

>         if (IS_ERR(op->fallback.blk)) {

>                 printk(KERN_ERR "Error allocating fallback algo %s\n", name);

> @@ -385,7 +390,7 @@ static void fallback_exit_blk(struct crypto_tfm *tfm)

>  {

>         struct geode_aes_op *op = crypto_tfm_ctx(tfm);

>

> -       crypto_free_blkcipher(op->fallback.blk);

> +       crypto_free_skcipher(op->fallback.blk);

>         op->fallback.blk = NULL;

>  }

>

> @@ -424,6 +429,9 @@ geode_ecb_decrypt(struct blkcipher_desc *desc,

>         struct blkcipher_walk walk;

>         int err, ret;

>

> +       if (nbytes % AES_BLOCK_SIZE)

> +               return -EINVAL;

> +

>         if (unlikely(op->keylen != AES_KEYSIZE_128))

>                 return fallback_blk_dec(desc, dst, src, nbytes);

>

> @@ -454,6 +462,9 @@ geode_ecb_encrypt(struct blkcipher_desc *desc,

>         struct blkcipher_walk walk;

>         int err, ret;

>

> +       if (nbytes % AES_BLOCK_SIZE)

> +               return -EINVAL;

> +

>         if (unlikely(op->keylen != AES_KEYSIZE_128))

>                 return fallback_blk_enc(desc, dst, src, nbytes);

>

> diff --git a/drivers/crypto/geode-aes.h b/drivers/crypto/geode-aes.h

> index f442ca972e3c..c5763a041bb8 100644

> --- a/drivers/crypto/geode-aes.h

> +++ b/drivers/crypto/geode-aes.h

> @@ -64,7 +64,7 @@ struct geode_aes_op {

>         u8 *iv;

>

>         union {

> -               struct crypto_blkcipher *blk;

> +               struct crypto_skcipher *blk;

>                 struct crypto_cipher *cip;

>         } fallback;

>         u32 keylen;

> --

> 2.21.0

>
Ard Biesheuvel Oct. 8, 2019, 11:38 a.m. UTC | #4 
On Sat, 5 Oct 2019 at 18:15, Gert Robben <t2@gert.gr> wrote:
>

> Op 05-10-2019 om 11:11 schreef Ard Biesheuvel:

> > Commit 79c65d179a40e145 ("crypto: cbc - Convert to skcipher") updated

> > the generic CBC template wrapper from a blkcipher to a skcipher algo,

> > to get away from the deprecated blkcipher interface. However, as a side

> > effect, drivers that instantiate CBC transforms using the blkcipher as

> > a fallback no longer work, since skciphers can wrap blkciphers but not

> > the other way around. This broke the geode-aes driver.

> >

> > So let's fix it by moving to the sync skcipher interface when allocating

> > the fallback. At the same time, align with the generic API for ECB and

> > CBC by rejecting inputs that are not a multiple of the AES block size.

> >

> > Fixes: 79c65d179a40e145 ("crypto: cbc - Convert to skcipher")

> > Cc: <stable@vger.kernel.org> # v4.20+ ONLY

> > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

> > ---

> > v2: pass dst and src scatterlist in the right order

> >      reject inputs that are not a multiple of the block size

>

> Yes, with this patch, the CRYPTO_MANAGER_EXTRA_TESTS output nothing

> (apart from "extra crypto tests enabled").

> All items in /proc/crypto have "selftest: passed" mentioned.

> "openssl speed -evp aes-128-cbc -elapsed -engine afalg" reaches the

> proper speed.

> And nginx (correctly) transfers files about 40% faster than without

> geode-aes.

>

> I didn't think about testing ecb before, because I don't use it.

> Now that I did, I tried the same openssl benchmark for ecb.

> But that only reaches software AES speed, and "time" also shows the work

> is being done in "user" instead of "sys" (see below).

> Yet I see no errors.

> (Maybe this is normal/expected, so I didn't look much further into it).

>

> Thank you,

> Gert

>

> # time openssl speed -evp aes-128-cbc -elapsed -engine afalg

> - - - 8< - - -

> type             16 bytes     64 bytes    256 bytes   1024 bytes   8192

> bytes  16384 bytes

> aes-128-cbc        135.82k      539.29k     2087.90k     7491.16k

> 29221.69k    34943.67k

>

> real    0m18.081s

> user    0m0.516s

> sys     0m17.541s

>

> # time openssl speed -evp aes-128-ecb -elapsed -engine afalg

> - - - 8< - - -

> type             16 bytes     64 bytes    256 bytes   1024 bytes   8192

> bytes  16384 bytes

> aes-128-ecb       4480.65k     5137.66k     5336.94k     5410.19k

> 5409.91k     5409.91k

>

> real    0m18.084s

> user    0m18.046s

> sys     0m0.012s

>


It seems likely that the ECB code in OpenSSL is not invoking the afalg
code at all. Since ECB is just the bare block cipher applied to each
block in the input, I wonder if it even uses a skcipher like interface
internally.
Herbert Xu Oct. 10, 2019, 12:58 p.m. UTC | #5 
On Sat, Oct 05, 2019 at 11:11:10AM +0200, Ard Biesheuvel wrote:
> Commit 79c65d179a40e145 ("crypto: cbc - Convert to skcipher") updated

> the generic CBC template wrapper from a blkcipher to a skcipher algo,

> to get away from the deprecated blkcipher interface. However, as a side

> effect, drivers that instantiate CBC transforms using the blkcipher as

> a fallback no longer work, since skciphers can wrap blkciphers but not

> the other way around. This broke the geode-aes driver.

> 

> So let's fix it by moving to the sync skcipher interface when allocating

> the fallback. At the same time, align with the generic API for ECB and

> CBC by rejecting inputs that are not a multiple of the AES block size.

> 

> Fixes: 79c65d179a40e145 ("crypto: cbc - Convert to skcipher")

> Cc: <stable@vger.kernel.org> # v4.20+ ONLY

> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

> ---

> v2: pass dst and src scatterlist in the right order

>     reject inputs that are not a multiple of the block size

> 

>  drivers/crypto/geode-aes.c | 57 +++++++++++---------

>  drivers/crypto/geode-aes.h |  2 +-

>  2 files changed, 34 insertions(+), 25 deletions(-)


Patch applied.  Thanks.
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
Florian Bezdeka Jan. 19, 2020, 10:02 a.m. UTC | #6 
Hi Ard,

Greg picked the non-backported version of the v2 patch and merged it into the 
4.9, 4.14 and 4.19 stable trees. The commit of the stable-queue repository [1] 
is [2].

Some days later he noticed that the non-backported version is not working as 
expected (failing the build) and he removed the patch from all affected stable 
trees again. The commit id is [3].

What are the right steps to get the backported version of this patch to the 
stable-queue and afterwards to the stable trees?

Thank you,
Florian

[1] git://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git
[2] ab6793e0731db6b937c47faf2ad95c5d9ef9ff86
[3] 23e4ec1db5b3ba3fb5cb60aac0b9b84e244e0a10

Am 08.10.19 um 13:36 schrieb Ard Biesheuvel:
> On Sat, 5 Oct 2019 at 14:22, Florian Bezdeka <florian@bezdeka.de> wrote:
>>
>> Commit 79c65d179a40e145 ("crypto: cbc - Convert to skcipher") updated
>> the generic CBC template wrapper from a blkcipher to a skcipher algo,
>> to get away from the deprecated blkcipher interface. However, as a side
>> effect, drivers that instantiate CBC transforms using the blkcipher as
>> a fallback no longer work, since skciphers can wrap blkciphers but not
>> the other way around. This broke the geode-aes driver.
>>
>> So let's fix it by moving to the sync skcipher interface when allocating
>> the fallback. At the same time, align with the generic API for ECB and
>> CBC by rejecting inputs that are not a multiple of the AES block size.
>>
>> Fixes: 79c65d179a40e145 ("crypto: cbc - Convert to skcipher")
>> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
>> Signed-off-by: Florian Bezdeka <florian@bezdeka.de>
>> ---
>>
>> Ard, I just followed your instructions and created this patch
>> for usage on an 4.19 kernel. The patch was successfully tested
>> on two different Geode systems.
>>
>> Can you please review again and forward to the stable tree if the patch
>> looks OK?
>>
> 
> The patch looks fine to me, but we cannot send it to -stable before
> the mainline version is merged.
> 
>>  drivers/crypto/geode-aes.c | 57 +++++++++++++++++++++++---------------
>>  drivers/crypto/geode-aes.h |  2 +-
>>  2 files changed, 35 insertions(+), 24 deletions(-)
>>
>> diff --git a/drivers/crypto/geode-aes.c b/drivers/crypto/geode-aes.c
>> index eb2a0a73cbed..cc33354d13c1 100644
>> --- a/drivers/crypto/geode-aes.c
>> +++ b/drivers/crypto/geode-aes.c
>> @@ -14,6 +14,7 @@
>>  #include <linux/spinlock.h>
>>  #include <crypto/algapi.h>
>>  #include <crypto/aes.h>
>> +#include <crypto/skcipher.h>
>>
>>  #include <linux/io.h>
>>  #include <linux/delay.h>
>> @@ -170,13 +171,15 @@ static int geode_setkey_blk(struct crypto_tfm *tfm, const u8 *key,
>>         /*
>>          * The requested key size is not supported by HW, do a fallback
>>          */
>> -       op->fallback.blk->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK;
>> -       op->fallback.blk->base.crt_flags |= (tfm->crt_flags & CRYPTO_TFM_REQ_MASK);
>> +       crypto_skcipher_clear_flags(op->fallback.blk, CRYPTO_TFM_REQ_MASK);
>> +       crypto_skcipher_set_flags(op->fallback.blk,
>> +                                 tfm->crt_flags & CRYPTO_TFM_REQ_MASK);
>>
>> -       ret = crypto_blkcipher_setkey(op->fallback.blk, key, len);
>> +       ret = crypto_skcipher_setkey(op->fallback.blk, key, len);
>>         if (ret) {
>>                 tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK;
>> -               tfm->crt_flags |= (op->fallback.blk->base.crt_flags & CRYPTO_TFM_RES_MASK);
>> +               tfm->crt_flags |= crypto_skcipher_get_flags(op->fallback.blk) &
>> +                                 CRYPTO_TFM_RES_MASK;
>>         }
>>         return ret;
>>  }
>> @@ -185,33 +188,28 @@ static int fallback_blk_dec(struct blkcipher_desc *desc,
>>                 struct scatterlist *dst, struct scatterlist *src,
>>                 unsigned int nbytes)
>>  {
>> -       unsigned int ret;
>> -       struct crypto_blkcipher *tfm;
>>         struct geode_aes_op *op = crypto_blkcipher_ctx(desc->tfm);
>> +       SKCIPHER_REQUEST_ON_STACK(req, op->fallback.blk);
>>
>> -       tfm = desc->tfm;
>> -       desc->tfm = op->fallback.blk;
>> -
>> -       ret = crypto_blkcipher_decrypt_iv(desc, dst, src, nbytes);
>> +       skcipher_request_set_tfm(req, op->fallback.blk);
>> +       skcipher_request_set_callback(req, 0, NULL, NULL);
>> +       skcipher_request_set_crypt(req, src, dst, nbytes, desc->info);
>>
>> -       desc->tfm = tfm;
>> -       return ret;
>> +       return crypto_skcipher_decrypt(req);
>>  }
>> +
>>  static int fallback_blk_enc(struct blkcipher_desc *desc,
>>                 struct scatterlist *dst, struct scatterlist *src,
>>                 unsigned int nbytes)
>>  {
>> -       unsigned int ret;
>> -       struct crypto_blkcipher *tfm;
>>         struct geode_aes_op *op = crypto_blkcipher_ctx(desc->tfm);
>> +       SKCIPHER_REQUEST_ON_STACK(req, op->fallback.blk);
>>
>> -       tfm = desc->tfm;
>> -       desc->tfm = op->fallback.blk;
>> -
>> -       ret = crypto_blkcipher_encrypt_iv(desc, dst, src, nbytes);
>> +       skcipher_request_set_tfm(req, op->fallback.blk);
>> +       skcipher_request_set_callback(req, 0, NULL, NULL);
>> +       skcipher_request_set_crypt(req, src, dst, nbytes, desc->info);
>>
>> -       desc->tfm = tfm;
>> -       return ret;
>> +       return crypto_skcipher_encrypt(req);
>>  }
>>
>>  static void
>> @@ -311,6 +309,9 @@ geode_cbc_decrypt(struct blkcipher_desc *desc,
>>         struct blkcipher_walk walk;
>>         int err, ret;
>>
>> +       if (nbytes % AES_BLOCK_SIZE)
>> +               return -EINVAL;
>> +
>>         if (unlikely(op->keylen != AES_KEYSIZE_128))
>>                 return fallback_blk_dec(desc, dst, src, nbytes);
>>
>> @@ -343,6 +344,9 @@ geode_cbc_encrypt(struct blkcipher_desc *desc,
>>         struct blkcipher_walk walk;
>>         int err, ret;
>>
>> +       if (nbytes % AES_BLOCK_SIZE)
>> +               return -EINVAL;
>> +
>>         if (unlikely(op->keylen != AES_KEYSIZE_128))
>>                 return fallback_blk_enc(desc, dst, src, nbytes);
>>
>> @@ -370,8 +374,9 @@ static int fallback_init_blk(struct crypto_tfm *tfm)
>>         const char *name = crypto_tfm_alg_name(tfm);
>>         struct geode_aes_op *op = crypto_tfm_ctx(tfm);
>>
>> -       op->fallback.blk = crypto_alloc_blkcipher(name, 0,
>> -                       CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK);
>> +       op->fallback.blk = crypto_alloc_skcipher(name, 0,
>> +                                                CRYPTO_ALG_ASYNC |
>> +                                                CRYPTO_ALG_NEED_FALLBACK);
>>
>>         if (IS_ERR(op->fallback.blk)) {
>>                 printk(KERN_ERR "Error allocating fallback algo %s\n", name);
>> @@ -385,7 +390,7 @@ static void fallback_exit_blk(struct crypto_tfm *tfm)
>>  {
>>         struct geode_aes_op *op = crypto_tfm_ctx(tfm);
>>
>> -       crypto_free_blkcipher(op->fallback.blk);
>> +       crypto_free_skcipher(op->fallback.blk);
>>         op->fallback.blk = NULL;
>>  }
>>
>> @@ -424,6 +429,9 @@ geode_ecb_decrypt(struct blkcipher_desc *desc,
>>         struct blkcipher_walk walk;
>>         int err, ret;
>>
>> +       if (nbytes % AES_BLOCK_SIZE)
>> +               return -EINVAL;
>> +
>>         if (unlikely(op->keylen != AES_KEYSIZE_128))
>>                 return fallback_blk_dec(desc, dst, src, nbytes);
>>
>> @@ -454,6 +462,9 @@ geode_ecb_encrypt(struct blkcipher_desc *desc,
>>         struct blkcipher_walk walk;
>>         int err, ret;
>>
>> +       if (nbytes % AES_BLOCK_SIZE)
>> +               return -EINVAL;
>> +
>>         if (unlikely(op->keylen != AES_KEYSIZE_128))
>>                 return fallback_blk_enc(desc, dst, src, nbytes);
>>
>> diff --git a/drivers/crypto/geode-aes.h b/drivers/crypto/geode-aes.h
>> index f442ca972e3c..c5763a041bb8 100644
>> --- a/drivers/crypto/geode-aes.h
>> +++ b/drivers/crypto/geode-aes.h
>> @@ -64,7 +64,7 @@ struct geode_aes_op {
>>         u8 *iv;
>>
>>         union {
>> -               struct crypto_blkcipher *blk;
>> +               struct crypto_skcipher *blk;
>>                 struct crypto_cipher *cip;
>>         } fallback;
>>         u32 keylen;
>> --
>> 2.21.0
>>
diff mbox series

Patch

diff --git a/drivers/crypto/geode-aes.c b/drivers/crypto/geode-aes.c
index d81a1297cb9e..940485112d15 100644
--- a/drivers/crypto/geode-aes.c
+++ b/drivers/crypto/geode-aes.c
@@ -10,6 +10,7 @@ 
 #include <linux/spinlock.h>
 #include <crypto/algapi.h>
 #include <crypto/aes.h>
+#include <crypto/skcipher.h>
 
 #include <linux/io.h>
 #include <linux/delay.h>
@@ -166,13 +167,15 @@  static int geode_setkey_blk(struct crypto_tfm *tfm, const u8 *key,
 	/*
 	 * The requested key size is not supported by HW, do a fallback
 	 */
-	op->fallback.blk->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK;
-	op->fallback.blk->base.crt_flags |= (tfm->crt_flags & CRYPTO_TFM_REQ_MASK);
+	crypto_sync_skcipher_clear_flags(op->fallback.blk, CRYPTO_TFM_REQ_MASK);
+	crypto_sync_skcipher_set_flags(op->fallback.blk,
+				       tfm->crt_flags & CRYPTO_TFM_REQ_MASK);
 
-	ret = crypto_blkcipher_setkey(op->fallback.blk, key, len);
+	ret = crypto_sync_skcipher_setkey(op->fallback.blk, key, len);
 	if (ret) {
 		tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK;
-		tfm->crt_flags |= (op->fallback.blk->base.crt_flags & CRYPTO_TFM_RES_MASK);
+		tfm->crt_flags |= crypto_sync_skcipher_get_flags(op->fallback.blk) &
+				  CRYPTO_TFM_RES_MASK;
 	}
 	return ret;
 }
@@ -181,33 +184,28 @@  static int fallback_blk_dec(struct blkcipher_desc *desc,
 		struct scatterlist *dst, struct scatterlist *src,
 		unsigned int nbytes)
 {
-	unsigned int ret;
-	struct crypto_blkcipher *tfm;
 	struct geode_aes_op *op = crypto_blkcipher_ctx(desc->tfm);
+	SYNC_SKCIPHER_REQUEST_ON_STACK(req, op->fallback.blk);
 
-	tfm = desc->tfm;
-	desc->tfm = op->fallback.blk;
-
-	ret = crypto_blkcipher_decrypt_iv(desc, dst, src, nbytes);
+	skcipher_request_set_sync_tfm(req, op->fallback.blk);
+	skcipher_request_set_callback(req, 0, NULL, NULL);
+	skcipher_request_set_crypt(req, src, dst, nbytes, desc->info);
 
-	desc->tfm = tfm;
-	return ret;
+	return crypto_skcipher_decrypt(req);
 }
+
 static int fallback_blk_enc(struct blkcipher_desc *desc,
 		struct scatterlist *dst, struct scatterlist *src,
 		unsigned int nbytes)
 {
-	unsigned int ret;
-	struct crypto_blkcipher *tfm;
 	struct geode_aes_op *op = crypto_blkcipher_ctx(desc->tfm);
+	SYNC_SKCIPHER_REQUEST_ON_STACK(req, op->fallback.blk);
 
-	tfm = desc->tfm;
-	desc->tfm = op->fallback.blk;
-
-	ret = crypto_blkcipher_encrypt_iv(desc, dst, src, nbytes);
+	skcipher_request_set_sync_tfm(req, op->fallback.blk);
+	skcipher_request_set_callback(req, 0, NULL, NULL);
+	skcipher_request_set_crypt(req, src, dst, nbytes, desc->info);
 
-	desc->tfm = tfm;
-	return ret;
+	return crypto_skcipher_encrypt(req);
 }
 
 static void
@@ -307,6 +305,9 @@  geode_cbc_decrypt(struct blkcipher_desc *desc,
 	struct blkcipher_walk walk;
 	int err, ret;
 
+	if (nbytes % AES_BLOCK_SIZE)
+		return -EINVAL;
+
 	if (unlikely(op->keylen != AES_KEYSIZE_128))
 		return fallback_blk_dec(desc, dst, src, nbytes);
 
@@ -339,6 +340,9 @@  geode_cbc_encrypt(struct blkcipher_desc *desc,
 	struct blkcipher_walk walk;
 	int err, ret;
 
+	if (nbytes % AES_BLOCK_SIZE)
+		return -EINVAL;
+
 	if (unlikely(op->keylen != AES_KEYSIZE_128))
 		return fallback_blk_enc(desc, dst, src, nbytes);
 
@@ -366,9 +370,8 @@  static int fallback_init_blk(struct crypto_tfm *tfm)
 	const char *name = crypto_tfm_alg_name(tfm);
 	struct geode_aes_op *op = crypto_tfm_ctx(tfm);
 
-	op->fallback.blk = crypto_alloc_blkcipher(name, 0,
-			CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK);
-
+	op->fallback.blk = crypto_alloc_sync_skcipher(name, 0,
+						      CRYPTO_ALG_NEED_FALLBACK);
 	if (IS_ERR(op->fallback.blk)) {
 		printk(KERN_ERR "Error allocating fallback algo %s\n", name);
 		return PTR_ERR(op->fallback.blk);
@@ -381,7 +384,7 @@  static void fallback_exit_blk(struct crypto_tfm *tfm)
 {
 	struct geode_aes_op *op = crypto_tfm_ctx(tfm);
 
-	crypto_free_blkcipher(op->fallback.blk);
+	crypto_free_sync_skcipher(op->fallback.blk);
 	op->fallback.blk = NULL;
 }
 
@@ -420,6 +423,9 @@  geode_ecb_decrypt(struct blkcipher_desc *desc,
 	struct blkcipher_walk walk;
 	int err, ret;
 
+	if (nbytes % AES_BLOCK_SIZE)
+		return -EINVAL;
+
 	if (unlikely(op->keylen != AES_KEYSIZE_128))
 		return fallback_blk_dec(desc, dst, src, nbytes);
 
@@ -450,6 +456,9 @@  geode_ecb_encrypt(struct blkcipher_desc *desc,
 	struct blkcipher_walk walk;
 	int err, ret;
 
+	if (nbytes % AES_BLOCK_SIZE)
+		return -EINVAL;
+
 	if (unlikely(op->keylen != AES_KEYSIZE_128))
 		return fallback_blk_enc(desc, dst, src, nbytes);
 
diff --git a/drivers/crypto/geode-aes.h b/drivers/crypto/geode-aes.h
index 5c6e131a8f9d..f8a86898ac22 100644
--- a/drivers/crypto/geode-aes.h
+++ b/drivers/crypto/geode-aes.h
@@ -60,7 +60,7 @@  struct geode_aes_op {
 	u8 *iv;
 
 	union {
-		struct crypto_blkcipher *blk;
+		struct crypto_sync_skcipher *blk;
 		struct crypto_cipher *cip;
 	} fallback;
 	u32 keylen;