[PATCH 5.9 086/757] crypto: caam/qi2 - add fallback for XTS with more than 8B IV

Greg Kroah-Hartman
2020-10-27T15:26:58Z

From: Andrei Botila <andrei.botila@nxp.com>

commit 36e2d7cfdcf17b6126863d884d4200191e922524 upstream.

A hardware limitation exists for CAAM until Era 9 which restricts
the accelerator to IVs with only 8 bytes. When CAAM has a lower era
a fallback is necessary to process 16 bytes IV.

Fixes: 226853ac3ebe ("crypto: caam/qi2 - add skcipher algorithms")
Cc: <stable@vger.kernel.org> # v4.20+
Signed-off-by: Andrei Botila <andrei.botila@nxp.com>
Reviewed-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/crypto/caam/Kconfig | 1
drivers/crypto/caam/caamalg_qi2.c | 80 +++++++++++++++++++++++++++++++++++---
drivers/crypto/caam/caamalg_qi2.h | 2
3 files changed, 78 insertions(+), 5 deletions(-)

--- a/drivers/crypto/caam/Kconfig
+++ b/drivers/crypto/caam/Kconfig
@@ -167,6 +167,7 @@ config CRYPTO_DEV_FSL_DPAA2_CAAM
select CRYPTO_AEAD
select CRYPTO_HASH
select CRYPTO_DES
+ select CRYPTO_XTS
help
CAAM driver for QorIQ Data Path Acceleration Architecture 2.
It handles DPSECI DPAA2 objects that sit on the Management Complex
--- a/drivers/crypto/caam/caamalg_qi2.c
+++ b/drivers/crypto/caam/caamalg_qi2.c
@@ -19,6 +19,7 @@
#include <linux/fsl/mc.h>
#include <soc/fsl/dpaa2-io.h>
#include <soc/fsl/dpaa2-fd.h>
+#include <asm/unaligned.h>

#define CAAM_CRA_PRIORITY 2000

@@ -80,6 +81,7 @@ struct caam_ctx {
struct alginfo adata;
struct alginfo cdata;
unsigned int authsize;
+ struct crypto_skcipher *fallback;
};

static void *dpaa2_caam_iova_to_virt(struct dpaa2_caam_priv *priv,
@@ -1056,12 +1058,17 @@ static int xts_skcipher_setkey(struct cr
struct device *dev = ctx->dev;
struct caam_flc *flc;
u32 *desc;
+ int err;

if (keylen != 2 * AES_MIN_KEY_SIZE && keylen != 2 * AES_MAX_KEY_SIZE) {
dev_dbg(dev, "key size mismatch\n");
return -EINVAL;
}

+ err = crypto_skcipher_setkey(ctx->fallback, key, keylen);
+ if (err)
+ return err;
+
ctx->cdata.keylen = keylen;
ctx->cdata.key_virt = key;
ctx->cdata.key_inline = true;
@@ -1443,6 +1450,14 @@ static void skcipher_decrypt_done(void *
skcipher_request_complete(req, ecode);
}

+static inline bool xts_skcipher_ivsize(struct skcipher_request *req)
+{
+ struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
+ unsigned int ivsize = crypto_skcipher_ivsize(skcipher);
+
+ return !!get_unaligned((u64 *)(req->iv + (ivsize / 2)));
+}
+
static int skcipher_encrypt(struct skcipher_request *req)
{
struct skcipher_edesc *edesc;
@@ -1459,6 +1474,18 @@ static int skcipher_encrypt(struct skcip
if (!req->cryptlen && !ctx->fallback)
return 0;

+ if (ctx->fallback && xts_skcipher_ivsize(req)) {
+ skcipher_request_set_tfm(&caam_req->fallback_req, ctx->fallback);
+ skcipher_request_set_callback(&caam_req->fallback_req,
+ req->base.flags,
+ req->base.complete,
+ req->base.data);
+ skcipher_request_set_crypt(&caam_req->fallback_req, req->src,
+ req->dst, req->cryptlen, req->iv);
+
+ return crypto_skcipher_encrypt(&caam_req->fallback_req);
+ }
+
/* allocate extended descriptor */
edesc = skcipher_edesc_alloc(req);
if (IS_ERR(edesc))
@@ -1494,6 +1521,19 @@ static int skcipher_decrypt(struct skcip
*/
if (!req->cryptlen && !ctx->fallback)
return 0;
+
+ if (ctx->fallback && xts_skcipher_ivsize(req)) {
+ skcipher_request_set_tfm(&caam_req->fallback_req, ctx->fallback);
+ skcipher_request_set_callback(&caam_req->fallback_req,
+ req->base.flags,
+ req->base.complete,
+ req->base.data);
+ skcipher_request_set_crypt(&caam_req->fallback_req, req->src,
+ req->dst, req->cryptlen, req->iv);
+
+ return crypto_skcipher_decrypt(&caam_req->fallback_req);
+ }
+
/* allocate extended descriptor */
edesc = skcipher_edesc_alloc(req);
if (IS_ERR(edesc))
@@ -1547,9 +1587,34 @@ static int caam_cra_init_skcipher(struct
struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
struct caam_skcipher_alg *caam_alg =
container_of(alg, typeof(*caam_alg), skcipher);
+ struct caam_ctx *ctx = crypto_skcipher_ctx(tfm);
+ u32 alg_aai = caam_alg->caam.class1_alg_type & OP_ALG_AAI_MASK;
+ int ret = 0;
+
+ if (alg_aai == OP_ALG_AAI_XTS) {
+ const char *tfm_name = crypto_tfm_alg_name(&tfm->base);
+ struct crypto_skcipher *fallback;
+
+ fallback = crypto_alloc_skcipher(tfm_name, 0,
+ CRYPTO_ALG_NEED_FALLBACK);
+ if (IS_ERR(fallback)) {
+ dev_err(ctx->dev, "Failed to allocate %s fallback: %ld\n",
+ tfm_name, PTR_ERR(fallback));
+ return PTR_ERR(fallback);
+ }
+
+ ctx->fallback = fallback;
+ crypto_skcipher_set_reqsize(tfm, sizeof(struct caam_request) +
+ crypto_skcipher_reqsize(fallback));
+ } else {
+ crypto_skcipher_set_reqsize(tfm, sizeof(struct caam_request));
+ }
+
+ ret = caam_cra_init(ctx, &caam_alg->caam, false);
+ if (ret && ctx->fallback)
+ crypto_free_skcipher(ctx->fallback);

- crypto_skcipher_set_reqsize(tfm, sizeof(struct caam_request));
- return caam_cra_init(crypto_skcipher_ctx(tfm), &caam_alg->caam, false);
+ return ret;
}

static int caam_cra_init_aead(struct crypto_aead *tfm)
@@ -1572,7 +1637,11 @@ static void caam_exit_common(struct caam

static void caam_cra_exit(struct crypto_skcipher *tfm)
{
- caam_exit_common(crypto_skcipher_ctx(tfm));
+ struct caam_ctx *ctx = crypto_skcipher_ctx(tfm);
+
+ if (ctx->fallback)
+ crypto_free_skcipher(ctx->fallback);
+ caam_exit_common(ctx);
}

static void caam_cra_exit_aead(struct crypto_aead *tfm)
@@ -1675,6 +1744,7 @@ static struct caam_skcipher_alg driver_a
.base = {
.cra_name = "xts(aes)",
.cra_driver_name = "xts-aes-caam-qi2",
+ .cra_flags = CRYPTO_ALG_NEED_FALLBACK,
.cra_blocksize = AES_BLOCK_SIZE,
},
.setkey = xts_skcipher_setkey,
@@ -2922,8 +2992,8 @@ static void caam_skcipher_alg_init(struc
alg->base.cra_module = THIS_MODULE;
alg->base.cra_priority = CAAM_CRA_PRIORITY;
alg->base.cra_ctxsize = sizeof(struct caam_ctx);
- alg->base.cra_flags = CRYPTO_ALG_ASYNC | CRYPTO_ALG_ALLOCATES_MEMORY |
- CRYPTO_ALG_KERN_DRIVER_ONLY;
+ alg->base.cra_flags |= (CRYPTO_ALG_ASYNC | CRYPTO_ALG_ALLOCATES_MEMORY |
+ CRYPTO_ALG_KERN_DRIVER_ONLY);

alg->init = caam_cra_init_skcipher;
alg->exit = caam_cra_exit;
--- a/drivers/crypto/caam/caamalg_qi2.h
+++ b/drivers/crypto/caam/caamalg_qi2.h
@@ -13,6 +13,7 @@
#include <linux/netdevice.h>
#include "dpseci.h"
#include "desc_constr.h"
+#include <crypto/skcipher.h>

#define DPAA2_CAAM_STORE_SIZE 16
/* NAPI weight *must* be a multiple of the store size. */
@@ -186,6 +187,7 @@ struct caam_request {
void (*cbk)(void *ctx, u32 err);
void *ctx;
void *edesc;
+ struct skcipher_request fallback_req;
};

/**