[PATCH v9 3/5] net: add a helper for making RARP packet

[Xiao Wang <xiao.w.wang@intel.com>]

Suggested-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Signed-off-by: Xiao Wang <xiao.w.wang@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
---
 lib/librte_net/Makefile            |  1 +
 lib/librte_net/rte_arp.c           | 42 ++++++++++++++++++++++++++++++++++++++
 lib/librte_net/rte_arp.h           | 14 +++++++++++++
 lib/librte_net/rte_net_version.map |  6 ++++++
 4 files changed, 63 insertions(+)
 create mode 100644 lib/librte_net/rte_arp.c

diff --git a/lib/librte_net/Makefile b/lib/librte_net/Makefile
index 5e8a76b68..ab290c382 100644
--- a/lib/librte_net/Makefile
+++ b/lib/librte_net/Makefile
@@ -13,6 +13,7 @@ LIBABIVER := 1
 
 SRCS-$(CONFIG_RTE_LIBRTE_NET) := rte_net.c
 SRCS-$(CONFIG_RTE_LIBRTE_NET) += rte_net_crc.c
+SRCS-$(CONFIG_RTE_LIBRTE_NET) += rte_arp.c
 
 # install includes
 SYMLINK-$(CONFIG_RTE_LIBRTE_NET)-include := rte_ip.h rte_tcp.h rte_udp.h rte_esp.h
diff --git a/lib/librte_net/rte_arp.c b/lib/librte_net/rte_arp.c
new file mode 100644
index 000000000..d7223b044
--- /dev/null
+++ b/lib/librte_net/rte_arp.c
@@ -0,0 +1,42 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2018 Intel Corporation
+ */
+
+#include <arpa/inet.h>
+
+#include <rte_arp.h>
+
+#define RARP_PKT_SIZE	64
+int
+rte_net_make_rarp_packet(struct rte_mbuf *mbuf, const struct ether_addr *mac)
+{
+	struct ether_hdr *eth_hdr;
+	struct arp_hdr *rarp;
+
+	if (mbuf->buf_len < RARP_PKT_SIZE)
+		return -1;
+
+	/* Ethernet header. */
+	eth_hdr = rte_pktmbuf_mtod(mbuf, struct ether_hdr *);
+	memset(eth_hdr->d_addr.addr_bytes, 0xff, ETHER_ADDR_LEN);
+	ether_addr_copy(mac, &eth_hdr->s_addr);
+	eth_hdr->ether_type = htons(ETHER_TYPE_RARP);
+
+	/* RARP header. */
+	rarp = (struct arp_hdr *)(eth_hdr + 1);
+	rarp->arp_hrd = htons(ARP_HRD_ETHER);
+	rarp->arp_pro = htons(ETHER_TYPE_IPv4);
+	rarp->arp_hln = ETHER_ADDR_LEN;
+	rarp->arp_pln = 4;
+	rarp->arp_op  = htons(ARP_OP_REVREQUEST);
+
+	ether_addr_copy(mac, &rarp->arp_data.arp_sha);
+	ether_addr_copy(mac, &rarp->arp_data.arp_tha);
+	memset(&rarp->arp_data.arp_sip, 0x00, 4);
+	memset(&rarp->arp_data.arp_tip, 0x00, 4);
+
+	mbuf->data_len = RARP_PKT_SIZE;
+	mbuf->pkt_len = RARP_PKT_SIZE;
+
+	return 0;
+}
diff --git a/lib/librte_net/rte_arp.h b/lib/librte_net/rte_arp.h
index 183641874..375635967 100644
--- a/lib/librte_net/rte_arp.h
+++ b/lib/librte_net/rte_arp.h
@@ -76,6 +76,20 @@ struct arp_hdr {
 	struct arp_ipv4 arp_data;
 } __attribute__((__packed__));
 
+/**
+ * Make a RARP packet based on MAC addr.
+ *
+ * @param mbuf
+ *   Pointer to the rte_mbuf structure
+ * @param mac
+ *   Pointer to the MAC addr
+ *
+ * @return
+ *   - 0 on success, negative on error
+ */
+int
+rte_net_make_rarp_packet(struct rte_mbuf *mbuf, const struct ether_addr *mac);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/lib/librte_net/rte_net_version.map b/lib/librte_net/rte_net_version.map
index 687c40eaf..213e6fd32 100644
--- a/lib/librte_net/rte_net_version.map
+++ b/lib/librte_net/rte_net_version.map
@@ -12,3 +12,9 @@ DPDK_17.05 {
 	rte_net_crc_set_alg;
 
 } DPDK_16.11;
+
+EXPERIMENTAL {
+	global:
+
+	rte_net_make_rarp_packet;
+} DPDK_17.05;
-- 
2.15.1