[PATCH v1] crypto/cnxk: minimal normalization on input

[Gowrishankar Muthukrishnan]

Fix modex to nomalize input only when MSW is zero.

Fixes: 5a3513caeb45 ("crypto/cnxk: add asymmetric session")
Cc: sta...@dpdk.org

Signed-off-by: Gowrishankar Muthukrishnan <gmuthukri...@marvell.com>
---
 drivers/crypto/cnxk/cnxk_ae.h | 30 +++++++++++++++++++++---------
 1 file changed, 21 insertions(+), 9 deletions(-)

diff --git a/drivers/crypto/cnxk/cnxk_ae.h b/drivers/crypto/cnxk/cnxk_ae.h
index ea11e093bf..66277172c6 100644
--- a/drivers/crypto/cnxk/cnxk_ae.h
+++ b/drivers/crypto/cnxk/cnxk_ae.h
@@ -49,13 +49,22 @@ struct cnxk_ae_sess {
 };
 
 static __rte_always_inline void
-cnxk_ae_modex_param_normalize(uint8_t **data, size_t *len)
+cnxk_ae_modex_param_normalize(uint8_t **data, size_t *len, size_t max)
 {
+       uint8_t msw_len = *len % 8;
+       uint64_t msw_val = 0;
        size_t i;
 
-       /* Strip leading NUL bytes */
-       for (i = 0; i < *len; i++) {
-               if ((*data)[i] != 0)
+       if (*len <= 8)
+               return;
+
+       memcpy(&msw_val, *data, msw_len);
+       if (msw_val != 0)
+               return;
+
+       for (i = msw_len; i < *len && (*len - i) < max; i += 8) {
+               memcpy(&msw_val, &(*data)[i], 8);
+               if (msw_val != 0)
                        break;
        }
        *data += i;
@@ -72,8 +81,8 @@ cnxk_ae_fill_modex_params(struct cnxk_ae_sess *sess,
        uint8_t *exp = xform->modex.exponent.data;
        uint8_t *mod = xform->modex.modulus.data;
 
-       cnxk_ae_modex_param_normalize(&mod, &mod_len);
-       cnxk_ae_modex_param_normalize(&exp, &exp_len);
+       cnxk_ae_modex_param_normalize(&mod, &mod_len, SIZE_MAX);
+       cnxk_ae_modex_param_normalize(&exp, &exp_len, mod_len);
 
        if (unlikely(exp_len == 0 || mod_len == 0))
                return -EINVAL;
@@ -282,7 +291,7 @@ cnxk_ae_modex_prep(struct rte_crypto_op *op, struct 
roc_ae_buf_ptr *meta_buf,
        struct rte_crypto_mod_op_param mod_op;
        uint64_t total_key_len;
        union cpt_inst_w4 w4;
-       uint32_t base_len;
+       size_t base_len;
        uint32_t dlen;
        uint8_t *dptr;
 
@@ -290,8 +299,11 @@ cnxk_ae_modex_prep(struct rte_crypto_op *op, struct 
roc_ae_buf_ptr *meta_buf,
 
        base_len = mod_op.base.length;
        if (unlikely(base_len > mod_len)) {
-               op->status = RTE_CRYPTO_OP_STATUS_INVALID_ARGS;
-               return -ENOTSUP;
+               cnxk_ae_modex_param_normalize(&mod_op.base.data, &base_len, 
mod_len);
+               if (base_len > mod_len) {
+                       op->status = RTE_CRYPTO_OP_STATUS_INVALID_ARGS;
+                       return -ENOTSUP;
+               }
        }
 
        total_key_len = mod_len + exp_len;
-- 
2.25.1