examples/l2fwd-crypto: fix packet length while decryption

[ upstream commit 62c0b44 ]

There were some padding left when a packet gets decrypted. This
patch removes those padding.
This patch also removes the padding left after verifying auth of
the packet.

Fixes: e2cdfbd ("examples/l2fwd-crypto: fix port id type")

Signed-off-by: Rohit Raj <rohit.raj@nxp.com>
Acked-by: Akhil Goyal <gakhil@marvell.com>

examples/l2fwd-crypto/main.c

@@ -616,12 +616,26 @@ l2fwd_simple_forward(struct rte_mbuf *m, uint16_t portid,
 		struct l2fwd_crypto_options *options)
 {
 	uint16_t dst_port;
+	uint32_t pad_len;
+	struct rte_ipv4_hdr *ip_hdr;
+	uint32_t ipdata_offset = sizeof(struct rte_ether_hdr);
 
+	ip_hdr = (struct rte_ipv4_hdr *)(rte_pktmbuf_mtod(m, char *) +
+					 ipdata_offset);
 	dst_port = l2fwd_dst_ports[portid];
 
 	if (options->mac_updating)
 		l2fwd_mac_updating(m, dst_port);
 
+	if (options->auth_xform.auth.op == RTE_CRYPTO_AUTH_OP_VERIFY)
+		rte_pktmbuf_trim(m, options->auth_xform.auth.digest_length);
+
+	if (options->cipher_xform.cipher.op == RTE_CRYPTO_CIPHER_OP_DECRYPT) {
+		pad_len = m->pkt_len - rte_be_to_cpu_16(ip_hdr->total_length) -
+			  ipdata_offset;
+		rte_pktmbuf_trim(m, pad_len);
+	}
+
 	l2fwd_send_packet(m, dst_port);
 }