[PATCH 38/40] cryptodev: clarify usage of private key in dh

[Arek Kusztal]

- clarified usage of private key in Diffie-Hellman.
CSRNG capable device should generate private key and then
use it for public key generation.

Signed-off-by: Arek Kusztal <arkadiuszx.kusztal at intel.com>
---
 lib/cryptodev/rte_crypto_asym.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/cryptodev/rte_crypto_asym.h b/lib/cryptodev/rte_crypto_asym.h
index 01b1fdd074..a6bb70ca3f 100644
--- a/lib/cryptodev/rte_crypto_asym.h
+++ b/lib/cryptodev/rte_crypto_asym.h
@@ -459,6 +459,10 @@ struct rte_crypto_dh_op_param {
 	 * Output generated private key when op_type is
 	 * DH PRIVATE_KEY_GENERATION
 	 * Input for RTE_CRYPTO_ASYM_KE_SHARED_SECRET_COMPUTE
+	 * In case priv_key.length is 0 and op_type is set with
+	 * RTE_CRYPTO_ASYM_KE_PUBLIC_KEY_GENERATE, CSRNG capable
+	 * device will generate private key and use it for public
+	 * key generation.
 	 */
 	union {
 		rte_crypto_uint pub_key;
-- 
2.13.6