crypto/ipsec_mb: fix GMAC parameters setting

[ upstream commit 837269c ]
AES-GMAC requires plaintext length to be 0 when using AES-GCM,
so only AAD data is used.

Fixes: a501609 ("crypto/ipsec_mb: fix length and offset settings")

Signed-off-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>
Acked-by: Fan Zhang <roy.fan.zhang@intel.com>
Acked-by: Radu Nicolau <radu.nicolau@intel.com>
Tested-by: Radu Nicolau <radu.nicolau@intel.com>

drivers/crypto/aesni_mb/rte_aesni_mb_pmd.c

@@ -1438,9 +1438,9 @@ set_mb_job_params(JOB_AES_HMAC *job, struct aesni_mb_qp *qp,
 					op->sym->aead.data.offset;
 			job->msg_len_to_hash_in_bytes =
 					op->sym->aead.data.length;
-		} else {
-			job->msg_len_to_cipher_in_bytes = 0;
+		} else { /* AES-GMAC only, only AAD used */
 			job->msg_len_to_hash_in_bytes = 0;
+			job->hash_start_src_offset_in_bytes = 0;
 		}
 
 		job->iv = rte_crypto_op_ctod_offset(op, uint8_t *,
@@ -1524,8 +1524,19 @@ set_mb_job_params(JOB_AES_HMAC *job, struct aesni_mb_qp *qp,
 					op->sym->cipher.data.length;
 		break;
 #endif
-	case CCM:
 	case GCM:
+		if (session->cipher.mode == NULL_CIPHER) {
+			/* AES-GMAC only (only AAD used) */
+			job->msg_len_to_cipher_in_bytes = 0;
+			job->cipher_start_src_offset_in_bytes = 0;
+		} else {
+			job->cipher_start_src_offset_in_bytes =
+					op->sym->aead.data.offset;
+			job->msg_len_to_cipher_in_bytes =
+					op->sym->aead.data.length;
+		}
+		break;
+	case CCM:
 #if IMB_VERSION(0, 54, 3) <= IMB_VERSION_NUM
 	case IMB_CIPHER_CHACHA20_POLY1305:
 #endif