diff --git a/lib/cryptodev/rte_crypto_asym.h b/lib/cryptodev/rte_crypto_asym.h
index c864b8a115..37dd3b9d86 100644
--- a/lib/cryptodev/rte_crypto_asym.h
+++ b/lib/cryptodev/rte_crypto_asym.h
@@ -362,53 +362,66 @@ struct rte_crypto_rsa_op_param {
 	enum rte_crypto_asym_op_type op_type;
 	/**< Type of RSA operation for transform */
 
-	rte_crypto_param message;
+	rte_crypto_param input;
 	/**<
-	 * Pointer to input data
-	 * - to be encrypted for RSA public encrypt.
-	 * - to be signed for RSA sign generation.
-	 * - to be authenticated for RSA sign verification.
+	 * When op_type == RTE_CRYPTO_ASYM_OP_ENCRYPT:
+	 * If padding.type = RTE_CRYPTO_RSA_PADDING_NONE
+	 * input should only be used along with cryptographically
+	 * secure padding scheme.
+	 * If padding.type = RTE_CRYPTO_RSA_PADDING_PKCS1_5
+	 * input shall be no longer than public modulus minus 11.
+	 * If padding.type = RTE_CRYPTO_RSA_PADDING_OAEP
+	 * input shall be no longer than public modulus -
+	 * 2 * len(hash) - 2.
+	 * When op_type == RTE_CRYPTO_ASYM_OP_SIGN:
 	 *
-	 * Pointer to output data
-	 * - for RSA private decrypt.
-	 * In this case the underlying array should have been
-	 * allocated with enough memory to hold plaintext output
-	 * (i.e. must be at least RSA key size). The message.length
-	 * field should be 0 and will be overwritten by the PMD
-	 * with the decrypted length.
+	 * If padding.type = RTE_CRYPTO_RSA_PADDING_NONE
+	 * input should only be used along with cryptographically
+	 * secure padding scheme.	 *
+	 * If padding.type = RTE_CRYPTO_RSA_PADDING_PKCS1_5 or
+	 * RTE_CRYPTO_RSA_PADDING_PSS
+	 * if the RTE_CRYPTO_RSA_FLAG_PT flag is set, input shall contain
+	 * the message to be signed, if this flag is not set,
+	 * input shall contain the digest of the message to be signed.
 	 *
-	 * All data is in Octet-string network byte order format.
-	 */
-
-	rte_crypto_param cipher;
-	/**<
-	 * Pointer to input data
-	 * - to be decrypted for RSA private decrypt.
+	 * When op_type == RTE_CRYPTO_ASYM_OP_DECRYPT:
 	 *
-	 * Pointer to output data
-	 * - for RSA public encrypt.
-	 * In this case the underlying array should have been allocated
-	 * with enough memory to hold ciphertext output (i.e. must be
-	 * at least RSA key size). The cipher.length field should
-	 * be 0 and will be overwritten by the PMD with the encrypted length.
+	 * Input shall contain previously encrypted RSA message.
 	 *
-	 * All data is in Octet-string network byte order format.
+	 * When op_type == RTE_CRYPTO_ASYM_OP_VERIFY:
+	 *
+	 * Input shall contain signature to be verified
 	 */
-
-	rte_crypto_param sign;
+	union {
+		rte_crypto_param output;
+		rte_crypto_param message;
+	};
 	/**<
-	 * Pointer to input data
-	 * - to be verified for RSA public decrypt.
+	 * When op_type == RTE_CRYPTO_ASYM_OP_ENCRYPT:
+	 *
+	 * Output shall contain encrypted data, output.length shall
+	 * be set to the length of encrypted data.
+	 *
+	 * When op_type == RTE_CRYPTO_ASYM_OP_DECRYPT/RTE_CRYPTO_ASYM_OP_SIGN:
 	 *
-	 * Pointer to output data
-	 * - for RSA private encrypt.
-	 * In this case the underlying array should have been allocated
-	 * with enough memory to hold signature output (i.e. must be
-	 * at least RSA key size). The sign.length field should
-	 * be 0 and will be overwritten by the PMD with the signature length.
+	 * If padding.type = RTE_CRYPTO_RSA_PADDING_NONE
+	 * output shall contain decrypted/signed data, but all leading zeros
+	 * shall be preserved. Therefore output.length should be
+	 * equal to the length of the modulus..
+	 * For other types of padding, output should contain
+	 * decrypted data, and output.length shall be set to the length
+	 * of decrypted data.
 	 *
-	 * All data is in Octet-string network byte order format.
+	 * When op_type == RTE_CRYPTO_ASYM_OP_VERIFY:
+	 *
+	 * If padding.type = RTE_CRYPTO_RSA_PADDING_NONE
+	 * output shall contain the public key decrypted signature.
+	 * All leading zeroes shall be preserved.
+	 *
+	 * For other padding types, the message should be set with data for the
+	 * signature to be compared with.
 	 */
+
 	struct rte_crypto_rsa_padding padding;
 	/**< RSA padding information */
 
